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National Institute of Technology Durgapur, INDIA

Students’ International Research Projects Technical Report 2010-2011

Volume 3

From Director’s Desk

Over the last few years, the primary focus of our endeavour is on excellence and

innovation, research being attributed the greatest emphasis. In pursuance of the “catch

them young” policy, the students are encouraged to take to research very early. To

motivate them further, the scheme of supporting their research visits to conferences in

India and abroad and for internship abroad was introduced. This has resulted in 76

students visiting premier universities and institutions all over the world in the last three

years in addition to hundreds of them presenting papers in conferences in India.

I are pleased that, like the last couple of years, we are going to publish “Students’

International Research Projects; Technical Report 2010-2011; Volume 3,” during the 7th

Convocation. Twenty seven students were supported by the Institute for research

internship and presenting papers in international conferences abroad this summer.

They visited all parts of the globe; from Massachusetts to Malaysia, from Geneva to

Germany, from New Zealand to Norway and from Stuttgart to Singapore. This report

will present a brief overview of their research pursuit.

I wish the authors great success in life and hope that some of them will take up

research as a professional career in future.

Professor T. Kumar

Director

National Institute of Technology Durgapur

Preface

"Somewhere, something incredible is waiting to be known." - Carl Sagan

Research is considered as a major component of innovation and a key to the development of modern societies. Over the past few decades, there has been an ever increasing importance being given to research work. Even as world economies are falling, more and more funds are being allocated to research. Not being ones to be left behind, National Institute of Technology Durgapur encourages and wholeheartedly supports research activities right from the bachelor level. The year 2011 saw twenty seven students undertake research projects in all parts of the world, ranging from Geneva to Massachusetts, Singapore to Auckland. Many of them have also published papers in renowned conferences and journals, a remarkable achievement, especially considering the fact most of them are at the undergraduates. Like the past few years, National Institute of Technology, Durgapur gave deserving students an opportunity to visit the Mecca of science and technology- CERN, Geneva. Three of the brightest students of the institute worked at the home of the Large Hadron Collider, something which even the most eminent of scientific personalities can only dream of doing. Three students were recipients of the prestigious DAAD (German Academic Exchange) scholarship and as many as six visited the National University of Singapore. All the students have gained valuable practical experience by working with eminent researchers and making use of high-tech research facilities. In addition to honing their technical skills, they had a wonderful opportunity for social and cultural exchange. The total number of students have remained fairly consistent with last year, where around thirty three undertook internships or attended conferences abroad - an indication of the institute’s unwavering presence in the international arena. Research is to see what everybody else has seen, and to think what nobody else has thought. A good CGPA is only a small component of an engineer’s degree. Only through practical and innovative application of the classroom concepts can one take that final step in the quest for excellence. For students aiming to pursue higher studies, these experiences are a look into the crystal ball, a taste of what to expect at the master’s or doctoral level. These are the experiences that shape one’s career. These are the experiences which provide one the encouragement to venture one step further; to discover the unknown.

Editors

Parnashi Chakraborty Final Year B. Tech. student, Electrical Engineering Prateek Mehta Final Year B. Tech. student, Chemical Engineering

http://thinkexist.com/quotation/research_is_to_see_what_everybody_else_has_seen/193718.html

http://thinkexist.com/quotation/research_is_to_see_what_everybody_else_has_seen/193718.html

AUTHORS

Agrawal Yogesh

Anand Anshu

Banerjee Subarno

Basak Rourav

Bhattacharya Sagarika

Bhattacharya Shrutilipi

Bose Sankari Prasad

Chakraborty Parnashi

Chaurasia Neeraj

Das Poulam

Das Sanjana

Ghatak Gourav

Goyal Sneha

Gupta Sumit

Kumar Pradip C

Majumder Aurijoy

Mehta Prateek

Namhata Argha

Pal Swadesh

AUTHORS

Pandey Rajesh

Rima Paul

Priyadarshini Monica

Roy Supriya

Samanta Somen

Sarkar Esha

Saxena Mohit

Vyjayanthi E. Vindhya Revathi

Contents

Title Author Page No.

RESEARCH INTERNSHIP:

LASER DOPPLER VELOCITY BIAS IN LARGE SCALE TURBULENT FLOWS; Ilmenau University of Technology, Germany

Agarwal Yogesh

1

CACHE AWARE STATIC TIMING ANALYSIS OF SYNCHRONOUS PROGRAMS; University of Auckland, New Zealand

Banerjee Subarno

3

OPTIMISATION OF IRON DOPING IN TITANIUM DIOXIDE FOR SELF CLEANING APPLICATIONS IN SOLAR MODULES; National University of Singapore

Chakraborty Parnashi 5

HYDROLOGICALINFORMATION SYSTEM FOR THE CATCHMENT OF RIVER KOSHI SYSTEM LYING IN NEPAL; Lund University, Sweden

Chaurasia Niraj

7

RESISTIVE SWITCHING IN COMPLEX OXIDE FILMS; National University of Singapore, Singapore

Das Poulami

9

EFFECT OF SUBSTRATE ON FERROMAGNETISM IN TANTALUM DOPED TITANIUM OXIDE THIN FILMS DEPOSITED BY PULSED LASER DEPOSITION; National University of Singapore, Singapore

Das Sanjana

11

STATE EQUATIONS FOR DIFFERENT PHASES; ITLR, University of Stuttgart, Germany

Ghatak Gourav 13

FINITE DIFFERENCE TIME DOMAIN (FDTD) SIMULATIONS AND ITS COMPUTER IMPLEMENTATION; National University of Singapore, Singapore

Goyal Sneha

15

GEO-SPATIAL VIDEO SEARCH ENGINE; Media Informatik, Technical University of Chemnitz, Germany

Gupta Sumit

17

MODELLING OF MOBILE RADIO CHANNELS; University of Agder, Grimstad, Norway

Kumar Pradeep C

19

USING STATIC OPTIMIZATION TO GUIDE DYNAMIC ROUTING AND WAVELENGTH ASSIGNMENT IN WDM NETWORKS; Asian Institute of Technology, Thailand

Majumdar Aurijoy

21

FIRST PRINCIPLES INVESTIGATION OF THE ADSORPTION OF DIFFERENT MOLECULES ON Cu (011) SURFACE; Hamburg University of Technology, Germany

Mehta Prateek

23

DEGRADATION OF DCAN IN DRINKING WATER SAMPLE; University of Massachusetts, Amherst, MA, USA

Namhata Argha 25

EXPERIMENTAL STUDY OF OXYGEN ENHANCED PREMIXED COUNTERFLOW FLAMES: EFFECT OF DILUENTS AND REACTANT PREHEATING; CNRS, ENSMA, University of Poitiers, France

Pal Swadesh

27

DEVELOPMENT OF TRIPLE GEM DETECTORS AND COSMIC RAY STAND FOR CMS EXPERIMENT; CERN, Geneva, Switzerland

Pandey Rajesh

29

EFFECT OF THE VO2 PHASE TRANSITIONS ON THE OPTICAL AND ELECTRICAL PROPERTIES OF ZnO; National University of Singapore, Singapore

Priyadarshini Monica 31

Title Author Page

No. DESIGN AND SIMULATION OF MATERIALS HANDLING TEST-BED USING SYNCHRONOUS SEMANTICS OF TIMEME University of Auckland, New Zealand

Roy Supriya

33

TRANSPONDER DATA RECORDER : FIRST IMPLEMENTATION AND APPLICATIONS; Tor Vergata University, Italy

Samanta Soumen 35

CALIBRATION OF FIELDS IN DEVELOPMENT OF TRIPLE-GEM DETECTOR AND BEAM TEST IN MAGNETIC FIELD; CERN, Geneva, Switzerland

Sarkar Esha 37

DESIGN OF A CAR LIFT WITH PRO/ENGINEER USING TOP DOWN DESIGN TECHNIQUE; American University of Armenia, Yerevan, Armenia

Saxena Mohit Raj

39

STUDY OF THE ELECTRONIC ASPECTS OF THE TRIPLE GEM DETECTOR; CERN, Geneva, Switzerland

Vyjayanthi E. Vindhya Revathi

41

CONFERENCES:

THRESHOLDING USING QUANTUM-DOT CELLULAR AUTOMATA; 7th International Conference on Innovations in Information Technology, Abu Dhabi, UAE

Anand Anshu S

43

OPTIMAL DESIGN OF A POWER ELECTRONIC SYSTEM FOR EFFICIENT AND RELIABLE POWER FLOW IN DISTRIBUTED WIND ENERGY BASED POWER SYSTEMS; International Conference on Energy and Electrical Systems (ICEES 2011), Kuala Lumpur, Malaysia

Basak Rourav

45

QOS ADAPTATION IN DISTRIBUTED MULTIMEDIA BASED COLLABORATIVE ENVIRONMENT; 4th International Conference on Modeling, Simulation and Applied Optimization – ICMSAO 2011, Kuala Lumpur, Malaysia

Bhattacharjee Shrutilipi

47

STRUCTURAL BIOINFORMATICS STUDY OF 5-ENOLPYRUVYLSHIKIMATE- 3-PHOSPHATE (EPSP) SYNTHASE FROM BORDETELLA PERTUSSIS; 45th International Conference on Global Challenges – the role of chemistry in giving their solutions – Bangkok, Thailand

Bhattacharya Sagarika

49

A NOVEL APPROACH OF POWER FLOW ANALYSIS BY POWER PERTURBATION METHOD; IEEE Control and System Graduate Research Colloquium, Shah Alam, Malaysia

Bose Sankari Prasad

51

CHEMICAL SYNTHESIS AND INVESTIGATION ON PHOTOLUMINESCENCE PROPERTIES OF TRIPHENYLPHOSPHINE FUNCTIONALIZED SINGLE WALL CARBON NANOTUBES; Xth International Conference on Nanostructured Materials - Nano 2010, Rome, Italy

Paul Rima

53

National Institute of Technology Durgapur, INDIA Students’ International Research Projects Technical Report 2010-2011 Volume 3

1

LASER DOPPLER VELOCITY BIAS IN LARGE SCALE TURBULENT FLOWS

Yogesh Kumar Agrawal

Final year B. Tech. student, Department of Mechanical Engineering National Institute of Technology Durgapur, INDIA

Institute of Thermodynamics and Fluid Mechanics

Ilmenau University of Technology, Germany May 10– July 20, 2011

Objective An Investigation of Laser Doppler velocity bias error on post processing data of Laser Doppler Anemometer for low speed large scale turbulent flow from Rayleigh-Benard convection experiments (Barrel of Ilmenau).

Introduction Laser Doppler Anemometer (LDA) is a popular experimental tool to measure the velocity field in a variety of fluid dynamics environments due to its non-intrusive nature and ability to discriminate flow direction. All measurements of a variable contain a certain amount of errors. Uncertainty in measurements is due to two fundamental types of errors, precision and bias error.Bias error show up in measurement as a displacement between the average measured value and average true value.

Bias Error sources Bias errors are predominantly the result of the seeding effect as on the flow, Specific geometry of the laser beams with respect to the flow and with respect to each other, and electronic effects that can be associated with the configuration of the counter processors.

Elimination Technique of Velocity Bias: Several techniques are proposed to eliminate the velocity bias have been proposed and most fall into two general categories:-

Post-Facto Techniques generate correction factors for the individual realization that are used in computing the mean flow field quantities. It works on the principle of weighted average. The following equation is used Generates correction factors for individual velocity realisations.

National Institute of Technology Durgapur, INDIA Students’ International Research Projects Technical Report 2010-2011 Volume 3 Where = the weighting factor, = estimator of mean and N = No. of realization. Free Running Processor Here estimator is exactly the arithmetic mean of all samples. Normalized error (β1) for one-dimensional flows exhibiting turbulence levels up to about 40% as Tropea, 1982.is β1 = (Tu1)2 Where Tu1 =turbulence level

meanu , are mean and fluctuating component of velocity respectively.

'u

Normalized Error in mean is expressed as Where = True mean velocity This normalized error decreases for 3-Dimensional turbulence. Results In order to document the effect of velocity bias at different location near to cold plate, the true mean velocity for all focal length are compared with estimated mean velocity. Figures show true mean and estimated mean of the x, y and z component of velocity (LDA1, LDA2 and LDA3) obtained with a non coincident three component LDA system with different position (0.00-99.20 mm) near to cold plate for focal length 310 mm. We find that average error in LDA1, LDA2 and LDA3 are 0.21, 0.0031 and 0.0033 respectively. There is very less bias error due to fringe spacing and threshold limit.

∑

∑

Conclusion Turbulence intensity up to (15<40)%, so Free running processor correction method is applicable for data of ‘Barrel of Ilmenau’. Bias error depends on each component of velocity and turbulence level.The Post processing data of Laser Doppler Anemometer from Rayleigh-Benard convection experiments is bias free due to negligible velocity bias error for each component of velocity. Acknowledgement I would like to thank Dr. Christian Resagk, Dept. of Mechanical Engineering, TU Ilmenau for giving me an opportunity to work under him and for guiding me throughout the project. I express my deep gratitude to DAAD India for offering an excellent opportunity through WISE (Working Internships in Science and Engineering) programme to the Indian students to pursue their research projects in Germany. I thank Dr.A.P.Baburaj, IIT Madras for constant guidance and inspiration and also Prof. Indrajit Basak, NIT Durgapur for recommending me as an eligible candidate for the proposed work. Lastly, I would like to extend my sincere thanks to my institute NIT Durgapur for allowing me to pursue the internship and providing financial aid.

=ii

1ig

== N

i

N

ii

g

gUU 1

r

r

Ur

meanuu 2/2 1)'( (%) Tu1 =

)( 'uuu mean ±=

( )u

uestiuμ

μβ 100*(%)1−=

uμ

2


CACHE AWARE STATIC TIMING ANALYSIS OF SYNCHRONOUS PROGRAMS

Subarno Banerjee

Final year B. Tech. student, Department of Computer Science & Engineering National Institute of Technology Durgapur, India

Department of Electrical & Computer Engineering University of Auckland, New Zealand

May 18 – July 19, 2011 Abstract

Embedded systems as they occur in application domains such as automotive, aeronautics, and industrial automation often have to satisfy hard real-time constraints. Safe and precise estimation of the worst-case execution time (WCET) of each task becomes necessary for such time-critical systems. For predictability, architectural features such as caches and pipelines are often disabled, simplifying the analysis, while losing throughput. Instead, the behaviour of various architectural features can be modelled for timing analysis. In this winter project, we develop a new approach for analysing cache behaviour, and compare it with existing approaches. Introduction

The idea of predictable architectures has gained momentum with the concept of a Precision Timed (PRET) Machine which was originally developed by researchers at UC Berkeley. The central idea of a PRET machine is to guarantee precise timing without sacrificing throughput. Another important objective is to simplify the timing analysis of code executing on PRET machines. PRETzel is the Precision Timed Computing research that brings together three different research groups, namely the University of Auckland in New Zealand, INRIA Research Lab in France and the real-time systems research group in Kiel University, Germany.

Predicting bounds on the execution time of a program is a difficult task. Yet, it is a requirement for time critical systems, where failing to meet a time constraint could cause a catastrophic disaster. Thus, various static timing analysis techniques are used to safely predict the execution time of a program, and

hence validate timing constraints. These static analysis techniques typically analyze all the possible execution paths in the control flow of the program, and the effect of the underlying architectural features on the execution time of an instruction.

When processor requests for a data, depending on whether it is currently stored in the cache (resulting in hit) or not (resulting in miss), the execution time of each instruction could vary between a few (1 to 3) cycles to large (10 to 1000) number of cycles. Hence, to precisely estimate that whether a reference to an instruction leads to a miss or a hit, the static analysis must consider the history of past instructions that were referenced. The BackSearching Approach

The reachability approach developed by researchers at NUS does a fixed-point computation analysis over the set of possible cache states at each control point. This takes too long for large programs and also risks running out of memory. The AbsInt tool gains significantly in terms of analysis time by applying a simple abstraction. However, this gain is at the loss of precision. Our approach needed to be precise and scalable at the same time.

Our algorithm takes the Control Flow Graph (CFG) of the program as input and annotates the Best and Worst Case number of cache misses per block. To deal with intra-block cache interferences, we group the instructions in each block into Instruction Clusters as per the mapping in the cache configuration and determine the number of intra-block misses. Finally, we keep the first (Reaching) and last (Leaving) instructions per cluster, which participate in inter-block cache interferences, and ignore the rest. For

3

National Institute of Technology Durgapur, INDIA Students’ International Research Projects Technical Report 2010-2011 Volume 3 each basic block, we then search all possible paths leading to the block in the backward direction and attempt to resolve for the Instruction Clusters as a hit or a miss. We BackSearch a particular path until all the Instruction Clusters are resolved or we reach the Start Block. A cluster C in the current block is resolved if we find a cluster C’ mapped to the same cache line. It results in a hit if the reaching instruction of C matches the leaving instruction of C’, and a miss otherwise. If we reach the Start Block, all unresolved instruction clusters will yield a miss.

Figure 1. Framework for Cache aware timing analysis

Intelligent BackSearching BackSearching will explore all possible paths for all the blocks. Intuitively, this will take too long for large programs. We observed that for majority of the programs, only a few paths actually resolve the instruction clusters. We optimized the algorithm by restricting it from exploring unnecessary paths. This was done at the cost of minimal memory usage. Before BackSearching, we build the cache access information for each block. This stores a ternary (never_accessed, accessed_before, accessed_here) value per cache line at each block. We resolve the clusters as a miss as soon as we find a never_accessed and BackSearch only for the clusters which have accessed_before. Once we find a accessed_here for a cluster, we resolve it as a hit or miss accordingly by comparison. This restricts the BackSearch only to the paths where the relevant cache lines are accessed thus significantly reducing the number of paths.

Results

The variation of WCRT with number of cache lines is in accordance with the expected behaviour. BackSearching predicts 0.3% to 0.6% tighter bounds on WCRT and is hence more precise than AbsInt. At the same time, both the approaches are nearly as fast.

Figure 2. Benchmarking BackSearching vs. AbsInt for a given program (Conveyor Belt) with varying cache lines: (a) WCRT,

(b) Analysis Time

Conclusion

We have developed a new approach for precise estimation of WCRT. Our approach uses lesser memory and gives tighter analysis. However, it does not scale well for sufficiently large programs. Currently, the work is being extended towards a scalable approach with configurable precision. Acknowledgement

I would like to thank Dr. P S Roop for hosting me as an intern and giving me this wonderful exposure to independent research. I convey my gratitude towards NIT Durgapur and OPJEMS for partially funding and making this internship possible. Thanks to Sid, Matthew & Eugene.

PRET-C program

TCCFG SCFG Translator

WCET Analyzer

Micro-architectural modelling

Control Flow Analysis

Cache Modeller Micro-architectural

modelling

Cache Analyzer Micro-architectural

modelling

Cache Config.

BackSearching

BackSearching AbsInt WCRT Analyzer WCRT

Result Cache Aware

TCCFG Cache Aware

SCFG Translator Reachability

4


OPTIMISATION OF IRON DOPING IN TITANIUM DIOXIDE FOR SELF CLEANING APPLICATIONS IN SOLAR MODULES

Parnashi Chakraborty

Final year B. Tech. student, Department of Electrical Engineering National Institute of Technology Durgapur, INDIA

Department of Electrical and Computer Engineering

National University of Singapore May 17 – July 15, 2011

Abstract It is necessary to improve the photocatalytic action of TiO2 for better self cleaning effect. In this experiment TiO2 is doped with different concentrations of iron. Also double layers of TiO2 and iron doped TiO2 are made to determine which sample has best photocatalytic effect. This data along with their transmittance and contact angle values help to determine the best sample to be used for self cleaning applications in solar modules. Introduction and Theory Incident energy on solar modules is lost through scattering or absorption by accumulated dust on outdoor panels. It is found that photovoltaic module efficiency drops by 33% for each 1 g/m2 of dust accumulation So superhydrophobicity or superhydrophilicity is used to make solar panels self cleaning. TiO2 shows superhydrophilicity and also undergoes photocatalysis. When UV light falls on TiO2 electron hole pairs are formed which reacts with ait and water to produce oxidizing agents. These oxidizing agents react with the large organic particles settled on the solar panel and decompose them. When rian water falls on it due to superhydrophilicity of TiO2 it gets cleaned. Experimental Ten samples are prepared as shown below:

Sample 1 Sample 2

Sample 3 Sample 4

Sample 5 Sample 6

Sample 7 Sample 8

Sample 9 Sample 10 Iron doped TiO2 is prepared using two phase based solvo thermal method. The glass substrates after being cleaned in piranha solution are dipped in the TiO2 colloidal solution and kept for 2 hours. Then they are annealed at 400 degree centigrade for 2 hours. The process is repeated for the second layer. These glass samples are then exposed to UV light for 6 hours with methyl orange (concentration 4 mg/l) to detect the photocatalytic degradation. Then a UV-vis spectrophotometer is used to detect degradation by measuring the absorbance spectrum of methyl orange (MO).

5


Fig 1: absorbance spectrum of MO

The peak absorbance is proportional to the concentration of MO

Fig 2: relative concentration of MO for different

samples In figure 2 C0 is the initial concentration of methyl orange and C is the concentration after 6 hours of photocatalysis

Fig 3: shows that transmittance of the ten samples is almost same as bare glass.

Fig 4: shows the contact angle of sample 3 which is 32.2 degrees.

Results and Discussion From the experiments conducted it can be concluded that iron doping improves photocatalysis of TiO2. Also photocatalytic efficiencies improve as concentration of iron doping increases. The results show that 0.8% iron doped TiO2 has better efficiency than 0.5% followed by 0.2% doping. Sample 8 which is the best shows a 7 percent improvement in efficiency. Also a heterogeneous structure like sample3 gives better results than sample 10 because the former acts as a pn junction which leads to better separation of the electron hole pairs required for photocatalysis. Conclusion Sample 3 has best photocatalytic effect, has transmittance same a bare glass and a contact angle of 32.2 degrees. Hence it is suitable to be used as a self cleaning material in solar modules. Acknowledgement I am grateful to my NIT, Durgapur and Electrical Engineering department for encouraging me and helping me financially to undertake this project. I am also grateful to my supervisor Prof. C. S. Bhatia from the ECE department of NUS for giving me the opportunity to work under his able guidance. I would like to thank Prof. Zeng for giving me the opportunity to work in his lab and last but not the least my guide Miss Xi Baojuan for her constant guidance and support.

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HYDROLOGICAL INFORMATION SYSTEM FOR THE CATCHMENT OF RIVER KOSHI SYSTEM LYING IN NEPAL

Niraj Chaurasia

Final year B. Tech. student, Department of Civil Engineering National Institute of Technology Durgapur, INDIA

Department of Water Resource Engineering

Lund University, Lund, SWEDEN May 27 – July 21, 2011

Abstract The Koshi River lies in Nepal and northern India, where it has caused devastating floods throughout the years. The river is known for its dynamic flow and high sediment load, leading to one of the largest alluvial fans in the world as well as avulsive shifting. The monsoonal dynamics in the region causes high fluctuation in the river discharge, with almost annual flooding, often with destructive consequences. The objective of this internship was to make a background study of the procured data for the catchment and perform hydrological analysis of parts of the catchment to develop a Hydrological Information System (HIS) which will be useful in developing Decision Support System (DSS) for the Koshi River System. Introduction Floods have been viewed as a purely technical problem in the past and measures like constructing dams, embankments and dikes have been adopted as a solution knowing the fact that floods cannot be completely controlled or regulated with technical solutions. Instead, floods should be integrated in water resource management through flood forecasting and emergency response plans to attain reduction in loss of life, improve in welfare and social stability as well as economic benefits. The DSS aims to increase cooperation between India and Nepal and manage the river Koshi System to mitigate floods by effectively controlling and managing flood in the catchment areas of the river Koshi and improving the means to

pass safely the discharge of river Koshi to the river Ganges. Model The HIS is a logical and structured system to collect data which are entered, checked and stored and subsequently compared, associated, related and combined to provide information in a form suitable to users. The input to HIS will be the analysed hydrological parameters such as raw and processed procured data. The following are the tasks performed for the preparation of HIS:

1. Analysis of different hydrological and meteorological data.

2. Linking of the different GIS layers of the catchment area to create sub-basin using the Geographical Information System (GIS) software.

3. Preparation of Index Map pointing out all the hydrological and meteorological stations for hydrological evaluation.

4. Detailed study of the catchment characteristics to visualize the natural terrain, type of land cover and role of the area in determining hydrological and meteorological characteristics.

5. Division of the prepared index map based on accessibility of area and availability of the hydrological or meteorological data.

6. Creation of GUI based interactive index map linked with the formatted data available for the catchment area.

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National Institute of Technology Durgapur, INDIA Students’ International Research Projects Technical Report 2010-2011 Volume 3 Methodology The first studies are conducted on a part of the catchment lying in Nepal to study the behaviour of the river as it exits Nepal and enters India. Later the area is limited further to a sub-basin of the catchment which is determined from the topography of the area. All collected data covers information regarding characteristics of the Kosi River catchment in Nepal. The methodology used for effective HIS preparation is listed below:

1. Data entry and validation of missing data.

2. Retrieval of data in working format.

3. Linking the formatted data to the indexed sub-basin to give following information: • Area covered • Different station lying in the area. • Types and form of data available. • Data analysis and reports.

Results • Visual analysis of catchment boundaries • Comparison of different hydrological

and meteorological station based on data availability and consistency.

• Double mass curves for precipitation data and Flood frequency analysis for discharge data.

• Sub-Basin Characteristics. • Different forms of presentation of rainfall

data such as Mass curve, Hyetograph, Mean precipitation (Isohyetal and Thiessen-Mean methods).

• Index map used for HIS development shown below:

Conclusion and Discussion The terrain parameter and the catchment characteristic is studied using Elevation Raster Images and DEM (Digital Elevation Model) produced in GIS software. The trend analysis done in this study is based on short time series data with many gaps in between and hence may not be reliable. Also the HIS thus prepared needs continuous modification and extension to achieve perfection that will be helpful in creating various hydrological modelling and the Decision Support System (DSS). Acknowledgement I express my deep gratitude to Dr. Vijay Kr Dwivedi, Professor, Civil Engineering, NIT Durgapur for initiating this internship under the project, “Development of Decision Support System for Integrated Water Resource Management in River Koshi System lying in India and Nepal – A cooperation program between University of Lund, Sweden and NIT Durgapur”. I am indebted for getting total financial support for this internship. I am thankful to Prof. Ronny Berndtsson, Water Resource Engineering, Lund University for extending full support during my internship at Lund.

8


RESISTIVE SWITCHING IN COMPLEX OXIDE FILMS

Poulami Das Final year B. Tech. student, Department of Electronics and Communication Engineering


NanoScience and Nanotechnology Initiative, NanoCore National University of Singapore, Singapore

May 29 – June 28, 2011 Abstract Resistive switching is phenomenon in which a dielectric which is normally insulating conducts under certain specific conditions. Materials which exhibit this phenomenon can be made to toggle between two resistance states on the application of suitable electrical voltage. The switching speed is found to be larger than several nanoseconds. It is thus useful for design of memory devices and has hence drawn tremendous attention of people all over the world in the recent past. However the reason behind this unusual phenomenon is yet unknown and an open question for discussion. Through my experiments I tried to check the validity of a model recently proposed. Introduction Resistive switching has been observed in a number of oxides so far. The same phenomenon was observed in metal/ insulating complex oxide/Nb-doped-SrTiO3 (NSTO) structures. Until now the phenomenon was attributed to the inherent conduction due to the oxygen vacancies of the oxide film and diffusion of the metal electrode leading to formation of conducting filaments. The actual driving force of the resistive switching, although electrically induced in most of the cases, is quite different. In my experiments I tried to exclude the possibility of diffusion of the metal electrodes or oxygen vacancies into the oxide layer. Instead we attribute the phenomenon to the formation of a quasi-conduction band (QCB) in the defect states of oxide that forms a continuum state with the conduction band of the substrate oxide.

Theory Firstly I tried to exclude the possibility of anodic dissolution or migration of oxygen vacancies as explanation for the phenomenon. Anodic dissolution of the metal electrode is possible only if adequate positive voltage is applied to an active electrode and the resulting cations can be driven by the strong electric field into the insulating film where they form filaments. Experiments conducted with inert Au electrode were same as those obtained with Cu electrode. The possibility of migration of oxygen vacancies as an explanation is eliminated because had it been the case, the applied electric field could only change the distribution of the positively charged oxygen vacancies. Therefore no insulating phase would appear even at high resistance states. For the purpose of verification low temperature switching properties were examined. The results found were consistent with the results in the room temperature device. We therefore propose a different mechanism for the phenomenon. The band gap of the substrate, NSTO, is about 3.9 eV. The band gap of complex oxide NdAlO3 chosen for study is 5.8 eV. Initially there is no conduction between the NSTO and oxide. On the application of suitable and sufficient negative bias, charges will be injected into the and will fill up the oxide defect levels from the metal side and the energy band of NSTO will be pushed down relative to the bands of the oxide. The Cu/Oxide and the NSTO bottom electrode constitute a capacitor. At a critical field when the charge density in the defect states reaches the Mott Limit (~ 3.6 x 1019 cm-

3), a quasi continuum state is formed which we call the QCB. Here we expect a similar switch for all on application of field. The applied voltage will then scale linearly with

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National Institute of Technology Durgapur, INDIA Students’ International Research Projects Technical Report 2010-2011 Volume 3 thickness under the condition that the dielectric constant remains field invariant. The state remains even on removal of the voltage due to overlap of electron wave functions. The device can be restored only with the help of opposite voltage. When the voltage reaches the difference between the QCB and the CB of NdAlO3 the electrons can now be bailed out of the QCB into the CB of NdAlO3 causing the QCB to vanish, resulting in the switch-off. Experimental A three-layered structure was prepared by depositing NdAlO3 films from the single crystal NdAlO3 target onto NSTO substrates, to be more specific (001) –oriented 0.5 wt % NSTO single crystal substrates. NdAlO3 films of 150 nm, 100nm and 50nm thickness was grown at 950 C under an O2 partial pressure of 1x10-2 Torr. The deposition was done using the pulsed layer deposition technique. The deposition time and laser energy was chosen as per the thickness. The sample was annealed in ambient O2 followed by cooling down to room temperature. Finally a Cu top electrode was deposited using a stencil metal mark. After wire bonding these samples were ready for current vs. voltage (I-V) measurement which was done using a sourcemeter across the two electrodes for each sample. The I-V characteristics were measured by scanning the voltage and reading the current with a compliance current of 0.1A. The compliance current is essential to prevent the sample from getting damaged due to high currents. The sign of voltage is the same as that applied on the top metal electrode. The plots were analyzed to check if switching takes place and if the results favour our proposed model. Results and Discussion

The plots in this figure represent the I-V curves for the 150 nm, 100 nm and 50 nm films respectively. The structures were

subjected to a voltage sequence 0->-12->0->12->0. When the voltage in the sample with 150 nm oxide film reaches about -11.3 V there is a sharp increase in the value of current, corresponding to the low-resistance state. The current saturates at 0.1 A due to application of compliance current. It is also noteworthy that the metallic state persists up to 3.4V after which the current suddenly falls and hence a high-resistance state is reached. For the 100 nm oxide film the corresponding voltages are -8.1 V and 3.4 V respectively. It is also interesting to note that the switching phenomenon occurs at a voltage, dependent on its thickness. Less negative voltage is required to switch a device whose insulating oxide layer thickness is greater as compared to another with lower thickness. Conclusion The results obtained support our proposed model. The QCB originates from the defect levels in the band gap of NdAlO3. This idea is supported by the change in the resistive state values after several cycles. The 50 nm oxide sample shows no switching, thus confirming that a minimum thickness is needed for the phenomenon to take place. It is noteworthy that the system switches back to insulating state at a voltage of 3.4 V which is approximately equal to the difference between the band gap of NdAlO3 and NSTO. Memory devices based on this phenomenon can become the front-runner among non volatile memories as they offer large switching speed, lower programming currents without sacrificing programming performance, retention and endurance. Acknowledgement I offer my sincere gratitude and thanks to Prof. Thirumalai Venky Venkatesan and Dr. Ariando for selecting and guiding me throughout the internship. I would like to thank Dr. Liu Zhiqi for helping me perform the experiments. Last but not the least, I would like to thank my parents, professors and friends for their best wishes and encouragement throughout.

10


EFFECT OF SUBSTRATE ON FERROMAGNETISM IN TANTALUM DOPED TITANIUM OXIDE THIN FILMS DEPOSITED BY PULSED LASER

DEPOSITION

Sanjana Das Final year B. Tech. student, Department of Electronics and Communication Engineering


NUSSNI Nanocore, Department of Electrical and Computer Engineering National University Of Singapore, Singapore

May 17 – July 15, 2011

Abstract The main objective of this project was toexplore the structural, electrical, magnetic and optical properties of titanium based novel oxide thin films. In this work, by using electrical and magnetic characterization, the magnetic effect in the functional material Ta-doped anatase TiO , when grown under specific conditions by using Pulsed Laser Deposition(PLD) is demonstrated. This material is known to be an intrinsic transparent conducting oxide (TCO). A Kondo effect was observed in niobium doped TiO2 grown at certain condition from the transport measurements which involved temperature dependent measurements of resistivity and the Hall Effect. The origin of magnetic moments in this system was suggested to be from the cation vacancy defects. This observation was confirmed from the SQUID measurements where ferromagnetism was observed in all the samples which were measured. This observation of an unambiguous magnetic effect in a nonmagnetic functional oxide doped with a nonmagnetic ion under specific growth conditions may open new avenues for manipulating defect magnetism in functional oxides that are interest to spintronics. Introduction Pulsed laser deposition Pulsed Laser Deposition Process is one of the most important deposition processes for fabricating thin films of multi-element compounds. In this process, high power pulsed laser beam is focused inside a vacuum chamber to strike a target of the desired

composition. Material is then vaporized from the target and deposited as a thin film on a substrate, which is heated to the required temperature. This process occurs in the presence of a background gas, oxygen, which is commonly used when depositing oxides to fully oxygenate the deposited films. Following are the common conditions for the depositions: Substrate:Single Crystal (001) NAO Deposition Time:10 minutes Laser Pulse Reperate: 5 Hz Spot Energy Density: 1.8 J/cm2

We have, till now, made depositions of 5% Ta doped samples on NAO and are concentrating our study on the films made. As the study is in process, more depositions are being done and studied.

Figure 1: Pulse Laser Deposition Experimental Characterization Techniques 1. Atomic Force Microscopy They reveal the surface characteristics of the samples of 5% Ta-TiO2 which were

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National Institute of Technology Durgapur, INDIA Students’ International Research Projects Technical Report 2010-2011 Volume 3 deposited on NAO at fixed oxygen partial pressure 1.4e-6 and at a different temperature. From the given data it can be concluded that the surface was more smooth at 7500C deposition.

Figure 2: AFM of TTO/NAO at d 2. X –ray diffraction The XRD patterns showed the presence of anatase and rutile peaks beside the substrate peaks. This suggests that these films are epitaxial with single anataseTiO2 phase.

Figure 3: XRD plots for 5% Ta:TiO2 grown at different temperature for constant partial pressure of oxygen 3. Physical property measurement system (transport) All the doped samples studied in this work exhibited metallic behaviour at high temperature; however the resistivity of all the samples showed an increase below a certain temperature with ln T behavior. Hall measurements were performed on these samples to examine the type and concentration of the free carriers. Therefore, the low temperature ln T-dependent resistivity is an indication of the Kondo effect. The Kondo effect is an unusual scattering mechanism of conduction electrons in a metal due to magnetic impurities, which contributes a term to the electrical resistivity

that increases logarithmically with temperature as the temperature T is lowered (as (log t)). 4. Magnetic property measurement system (squid) Ferromagnetism observed is in accordance with RKKY Mechanism due to coupling mechanism of localized d shell electron spins in a conductor in terms of an interaction through the conduction electrons: when the conduction carriers are temporarily around a localized magnetic moment, the spins of the carriers are polarized by this magnetic moment. Conclusion The characterisations of the thin film grown substrates are carried out in SQUID but we did not find any significant magnetism (defect magnetism) due to thin film deposited on NAO. The possible reasons might be: 1. We have to find more accurate and optimised condition for deposition of 5% Ta TiO2 2. The substrate itself is Para magnetic hence we did not get significant magnetism due to the thin film due to subtraction, the magnetism is getting distorted due to high magnetism of the NAO substrates only (refer to the figure above). The substrate shows steep rise in magnetism in the range of 2- 50 K. Acknowledgement I would like to thank Professor T. Venky Venkatesan (Director, Nanocore, NUS, Singapore) and Sankar Dhar (PI, Nanocore, NUS Singapore) for their support and guidance. I would also like to convey my sincere regards to Prof Shubhamay Haldar and the Professors of my Department at N.I.T. Durgapur for their guidance and motivation. I would like to give my heartfelt gratitude to my parents, teachers and friends for their continual support and good wishes.

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STATE EQUATIONS FOR DIFFERENT PHASES

Gourav Ghatak Final year B. Tech. student, Department of Mechanical Engineering


Department of Mechanical Engineering ITLR, University of Stuttgart, Germany

May 10 – July 29, 2011

Abstract In simulations of compressible multi phase flows there might be gas, liquid and solid existing together (e.g. rain drops and ice crystals in clouds, natural gases and oils in oil wells). For the numerical simulation of such compressible flows, state equations are needed for each individual phase. However, this has the disadvantage that between the individual phases discontinuities exist which come from the different state equations used in the different areas. Therefore, the aim of the present study is to investigate different state equations analytically and explore if these equations (like Van der Walls, virial equations) can be used for problems with different phases . Introduction Below the critical temperature the isotherm defined by the Peng-Robinson equation oscillates and fails to describe phase transition in real substances in this region. To fix this problem James Clark Maxwell (1875) replaced the isotherm between the dark points in Fig 1 with a horizontal line positioned so that the areas of the two hatched regions are equal. The flat line portion of the isotherm now corresponds to liquid-vapour equilibrium. He justified this through the balance of mechanical work. Work done on the system should be equal to work released from it (area on a PV diagram corresponds to mechanical work). That’s because the change in the free energy function A (T, V) equals the work done during a reversible process the free energy function being a state variable should take on a unique value regardless of path. Maxwell’s argument is not totally convincing since it requires a reversible path through a region of

thermodynamic instability. Nevertheless, more subtle arguments based on modern theories of phase equilibrium seem to confirm the Maxwell Equal Area construction and it remains a valid modification of the cubic equations of state.

Fig 1: Maxwell’s Rule

Theory Using Matlab code, one can generate the modified isotherms for liquid-vapour phase transition and calculate the saturation pressure at that temperature and saturated liquid and gas volumes at those pressures and temperatures. The various steps involved are as follows: (i) Use Antoine equation to calculate the saturation pressure corresponding to a particular temperature.

log P= 10 TCBA+

−

The pressure thus obtained is in mm of Hg. For Water,

A

B

C

Tmin(°C)

Tmax (°C)

Water

8.071

1730.6

233.42

1

100

Water

8.140

1810.9

244.48

99

374

13


Fig 2: Family of Isotherms for water using the Peng-Robinson equation

This equation gives fairly satisfactory results for saturation pressure. (ii) Now for this saturation pressure and corresponding temperature we find the roots (values of volume) of the Peng-Robinson equation. The maximum and the minimum of these roots are the saturated vapour and saturated liquid volumes respectively. (iii) Now the new isotherm is defined piecewise upto the saturated liquid volume by the PR equation, from the saturated liquid to the saturated vapour volume by a horizontal line corresponding to the saturation pressure calculated in step(i), and, from the saturated vapour volume onwards again by the PR equation.

Results and Discussion Fig 3: Comparison of the generated isotherms

with the experimental thermophysical data Finally we compare the data obtained by us with the experimental data from steam tables. For this the family of modified isotherms were

first plotted by using the developed Matlab codes and then plotting the experimental data on the same figure in order to see the deviation of the derived isotherms from reality as in Fig 3. This helps us in comparing the two and judging the accuracy and practicality of the derived results. This is particularly useful if an error analysis is to be carried out. It also helps to come to any conclusion regarding the success of this attempt Conclusion Hence, we are able to generate a code for defining the isotherms for describing liquid-vapour phase transition. The codes used are simple and user friendly. The method adopted is fairly accurate and requires very little computational time due to absence of iterations. The saturation pressures predicted are fairly accurate. The experimental expanded vapour volumes are quite in agreement with the isotherms. However, there are certain limitations as in any method. The isotherms deviate slightly to the right with respect to the saturated liquid and vapour volume. This deviation increases as the temperature and pressure increases and one moves towards the critical point. Hence these isotherms might not give very accurate results at very high temperatures and pressures. However this is of lesser significance from industrial point of view as one usually operates away from the critical point. Acknowledgement I am extremely grateful to Prof. Dr.-Ing. habil. Bernhard Weigand, for providing me this golden opportunity to work under him at the University of Stuttgart. At the same time I am equally thankful to my home institute, NIT Durgapur, and my supervisor Prof A.K. Pramanick who has played pivotal role in fetching me this opportunity. I would also like to thank DAAD on a special note for making this dream of pursuing research work in Germany come true.

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http://www.uni-stuttgart.de/itlr/mitarbeiter/display.php?id=weigand&lang=en

http://www.uni-stuttgart.de/itlr/mitarbeiter/display.php?id=weigand&lang=en


FINITE DIFFERENCE TIME DOMAIN (FDTD) SIMULATIONS AND IT’S COMPUTER IMPLEMENTATION

Sneha Goyal

Final year B. Tech. student, Department of Information Technology National Institute of Technology Durgapur, INDIA

Department of Electronics and Computer Engineering

National University of Singapore, July-August, 2011

Abstract The FDTD method has been used extensively in the modelling of electromagnetic wave scattering from complex non-canonical objects. The FDTD method is the simplest of the full-wave techniques used to solve problems in electromagnetics. It can accurately tackle a wide range of problems. The FDTD method employs finite differences as approximations to both the spatial and temporal derivatives that appear in Maxwell’s equations especially Faradays laws and Ampere’s laws. The main aim is to provide computer implementation of FDTD simulation in Euclidian space. Introduction Consider a region of space that has no electric or magnetic current sources, but may have materials that absorb electric or magnetic field energy. The time-dependent Maxwell’s equations are given in differential and integral forms by:

oH Et

μ ∂− = ∇×

∂ aand

o rE Ht

ε ε ∂= ∇×

∂

Their component representation is:

yx zo

EH Et y

μ−∂∂ ∂

= −∂ ∂ ∂z 1.1

y x z

o

H E Et z

μ∂ ∂ ∂

− = −∂ ∂ ∂x

1.2

y xzo

E EHt x

μ∂ ∂∂

− = −∂ ∂ ∂

y x zo r

E H Ht z

ε εx

∂ ∂ ∂= −

∂ ∂ ∂ 1.5

y xzo r

H HEt x y

ε ε∂ ∂∂

= −∂ ∂ ∂

1.6

Theory The FDTD method employs finite differences as approximations to both the spatial and temporal derivatives that appear in Maxwell’s equations. The above stated six equations 1.1-1.6 are for the FDTD simulations in 3D. They are reduced accordingly to yield the update equations for 1D and 2D. Then using those equations algorithms for the computer implementation are stated which can be coded into a program. 1D simulation: To reduce the equation to 1D form a z-directed, x-polarized TEM wave (Hz = Ez = 0), is made incident upon a modelled geometry with no variations in the y and z direction, i.e, 0 & 0

y z∂ ∂= =

∂ ∂

equations 1.1-1.6 reduce down to the 1D

y zH Et

μx

∂ ∂=

∂ ∂ and

yzo r

HEt x

ε ε∂∂

=∂ ∂

.

2D simulation: Here 0z∂=

∂ and two sets

of equations are yielded as follows:

TM MODE:

1x zH Et yμ

∂ ∂= −

∂ ∂

1y zH E

t xμ∂ ∂

= −∂ ∂

y 1.3

yx zo r

HE Ht y

ε ε∂∂ ∂

= −∂ ∂ ∂z

1.4

15


1 ( )y xzH HE

t x y∂ ∂∂

= −∂ ∈ ∂ ∂

and TE MODE: 1x zE H

t∂

y∂

=∂ ∈ ∂

1y z

E Ht x

∂ ∂= −

∂ ∈ ∂

1 ( yxz )

EEHt yμ x

∂∂∂=− −

∂ ∂ ∂

3D simulation: In this case the governing equations are eq. 1.1-1.6. Boundary Conditions: The FDTD method also has boundary conditions. The various boundary conditions are:

• Mur’s Absorbing Boundary • Total Field Scatter Field Boundary • Perfect Electric Conductor(PEC) • Perfect Magnetic Conductor(PMC) • Periodic • Perfectly Matched Layer

Types of Sources: The simplest classification of FDTD sources is

• Soft Sources • Hard Sources

Some specific types of sources are: • Point sources(dipoles) • Gaussian Source • Thin Lens Source • Plane wave Sources • Mode Sources • Total Field Scatter Field Sources

Some other Factors to be considered:

• Permittivity • Permeability • Electric Conductivity • Magnetic Conductivity

Discussions The computer implementation for one two and three dimensional simulation can be easily done. When writing a computer

program to implement the FDTD algorithm, one does not bother trying to construct a program that explicitly uses offsets of one-half. Nodes are stored in arrays and, as is standard practice, individual array elements are specified with integer indices. Thus, the computer program (or, perhaps more correctly, the author of the computer program) implicitly incorporates the fact that electric and magnetic fields are offset while using only integer indices to specify location. We declare two arrays, ez and hy, which will contain the Ez and Hy fields. All aspects like boundary conditions, source type are all considered while implementing the simulations in C/C++. The result can be observed using Excel Plot. Conclusion The FDTD method can be extended beyond Euclidian space. We need to change the equations for 3D(Given here) to spherical space. The radius of the sphere may be considered very large (close to infinity) to represent non- Euclidian space. Acknowledgement First and foremost I would like to express my sincere gratitude to the professors of Dept. of Information Technology, NIT Durgapur for their guidance and support. Next I would like to thank Prof. Venky Venkatesan, Director-NUSNNI for proving me the financial aid and Prof. Aaron Danner for guiding me and giving me such a great opportunity. Finally, I would like thank my parents and my friends for their continuous support and encouragement. Key words TEM: Transverse Electro-Magnetic TE: Transverse Electric TM: Transverse Magnetic

- Vacuum Permittivity - Relative permittivity

µ-Permeability

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GEO – SPATIAL VIDEO SEARCH ENGINE

Sumit Gupta Final Year B. Tech. student, Department of Computer Science and Engineering

National Institute of Technology, Durgapur, India

Media Informatik, Technical University of Chemnitz, Germany May 2011- July 2011

Abstract Whether looking for geo-tagged photos shot at the location of interest, the nearest coffee shop on a GPS-enabled smatphone, or nearby friends via social networking sites, more and more people are using location-aware search services. Therefore, During my Internship in Technical University of Chemnitz, Germany in summer 2011, I developed a new Video search Engine in JAVA using Apache SOLR which is based on location data of the Videos aiming at giving users the capability to search Videos that were recorded nearby a specific location of interest within a boundary specified. It also enables the users to jump to that segment of the Video which was recorded nearest to the user Query and also allows them to seek the Video by using Google Map markers. Introduction Location-aware search engines are gaining popularity day by day among internet users. Users would wish to watch videos or the segment of that video which were recorded at a particular location. Thus, my Search Engine emphasises on the Videos having location data attached with the timestamps. Based on the GPX track of the Video, it uses Apache SOLR to create an index of this track and aims at retrieving the Videos which were recorded nearby the location represented by the search field lying in a bounded region of radius represented by the distance input parameter sorted by the distance from the searched location. The top 10 Videos matching the search query are returned in JSON format using GSON Library from Google from the Web Servlet using Embedded SOLR server that maintains the indexed documents having video file name, location and timestamps as

its fields. Each Video Object returned from the Servlet also have three frames information representing the start, the nearest match and the end of the video. The Web User Interface created uses this JSON object to retrieve the location data and uses Google static Maps API to show the exact location and distance of the frames from the searched location. By clicking these google maps images, the web interface plays the video using flowplayer and also shows geographical information related to the video using a map generated by Google Maps API having markers which can be used to jump seek to various timestamps of the Video which are geotagged with the Location associated with these markers. Theory Tools Used: • JAVA ( IDE used : Eclipse ) • Apache SOLR 3.3 ( for indexing the

location data with timestamps for fast search )

• Geocoder – Java API ( for geocoding and reverse geocoding of location data )

• Gson Java API ( for creating the JSON Object )

• MediaInfo Java Wrapper ( for getting duration and starting timestamp of the Videos )

• mp4 split Java API ( for splitting the video file to pass from Web Servlet to the web player )

• flowplayer Javascript ( for playing the video and pseudo streaming )

• Google Maps Javascript API v3( for displaying map with the location of retrieved videos )

• ffmpeg unix utility ( for extracting the start and the end frames from the Videos )

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National Institute of Technology Durgapur, INDIA Students’ International Research Projects Technical Report 2010-2011 Volume 3 Getting Location Data: Presently, there is no such codec for video which can store location data so the geographical coordinates related to the timestamps in the videos were retrieved from the GPX file contain the locations and the time of recording in the GPS exchange format. We used mediaInfo Java wrapper to get the start timestamp and the duration and calculated the end timestamp of the Video. The gpx parser designed retrieved the list of coinciding video timestamps and location data on the gpx track. Indexing Location data: The list retrieved from the gpx parser for each video is indexed in to SOLR Index by creating Solr Documents each containing the following fields,

• name – file name of the video • store – the location data in (latitude,

longitude) form • time – the offset in ms in the video

file • id – unique id of the document (

name + timestamp ) • startEnd – the location data of the

start and end of the video • endTime – the offset of the last

timestamp having location data Each document represents a segment of the video between two geo-tagged timestamps. Maintaining the Index: The videos are regularly uploaded with the gpx file associated with it to the source folder and the index have to be maintained regularly so a thread is created which checks the source folder for updates and it indexes the new uploaded videos if any and creates a folder in the IndexedVideo directory with the video, the gpx file, an xml file containing all the SOLR Documents and the mediainfo text file having information about the video. The User Interface: The web user interface is developed using Java Servlet which runs on Tomcat 7 server. Results The Geo-spatial Video Search Engine

User can then click on any segment of the video he/she wish to view and then the player and the map will be displayed as follows. The user can double click on any marker in the map to seek to a timestamp in the video recorded at the location associated with that marker

Conclusions To conclude, this internship has greatly helped me in building my assets and has paved the way for a future career in research. It has not only helped me in realizing my potential but also has provided me with experience, memories and confidence. Acknowledgements I would like to thank everybody who has made this internship possible and fruitful! I would like to thank NIT Durgapur for funding my expenses. I would also like to extend my gratitude to Professors Dr. Maximian Eibl, chair of the Media Retrieval Group of Technical University of Chemnitz, for his guidance and help during my stay.

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MODELLING OF MOBILE RADIO CHANNELS

Pradeep Kumar C Final year B. Tech. student, Department of Electronics and Communication Engineering


Mobile Communications Group University of Agder, Grimstad, Norway

May 15 – July 15, 2011 Abstract A profound knowledge of mobile radio channels is required systems. In addition, knowledge of channel behaviour in mobile radio communication is extensively recommended for the study of transmitter/receiver performances. Various kinds of such mobile fading channel simulators are developed using MATLAB and embedded into MATLAB software as a toolbox. My project was to improve the toolbox and to test it for the development, evaluation, and assessment at practical conditions of present and future mobile radio communication. Introduction Mainly, two goals are aimed at. The first one is to find stochastic processes especially suitable for modelling frequency-nonselective and frequency-selective mobile radio channels. In this context, we will establish a channel model described by ideal (not realizable) stochastic processes as the reference model or as the analytical model. The secondgoal is the derivation of efficient and flexible simulation models for various typical mobile radio scenarios. The usefulness and the quality of a reference model and the corresponding simulation model are ultimately judged on how well its individual statistics can be adapted to the statistical properties of measured or specified channels. In order to test and to confirm the correctness of the implemented channel simulators, simulation results are compared with the measured model or the reference model under different scenarios. In addition to that selection of the simulation time duration, sampling rate and size of the samples were considered.

Theory Whether the frequency selective or frequency non selective channel, it can be modelled by using the coloured Gaussian random processes. Rice method is considered as the reference model for all channel models which is based on a superposition of an infinite number of sinusoids with constant gains and equidistant frequencies, and random phases.

. Realization in this case is impossible because an infinite number of sinusoids Ni cannot be implemented on a computer or on a hardware platform. Hence it is only considered as the stochastic reference model. So, Principle of deterministic channel modelling comes up with finite value for Ni. The principle can be summarized in the following five design steps: Step 1: Starting point is the (non-realizable) reference model; based on one or several Gaussian processes, each with prescribed autocorrelation function. Step 2: Derive a stochastic simulation model from the reference model by replacing each Gaussian process by sum-of sinusoids with fixed gains, fixed frequencies, and random phases. Step 3: Determine a deterministic simulation model by fixing all model parameters of the stochastic simulation model including the phases. Step 4: Compute the model parameters of the simulation model by fitting the relevant statistical properties of the deterministic (or stochastic) simulation model to those of the reference model.

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National Institute of Technology Durgapur, INDIA Students’ International Research Projects Technical Report 2010-2011 Volume 3 Step 5: Perform the simulation of one (or some few) sample functions (Deterministic processes or waveforms). The five steps of the principle of deterministic channel modelling are shown in figure below.

To fully exploit the advantages of the above mentioned Sum-of-sinusoids processes, one must carefully determine the model parameters i.e., the discrete Doppler frequencies, the path gains and the phases. This parameterization problem is solved using deterministic and stochastic methods. The philosophy behind the deterministic methods is to compute constant values for all principle model parameters, while stochastic methods assume that the discrete Doppler frequencies and/or gains are random variables. Deterministic methods include Jakes method, original Rice method, the method of equal distances(MED), the mean square error method (MSEM), the method of equal areas (MEA), the method of exact Doppler spread(MEDS), Lp-norm method(LPNM) etc. Typical representatives of stochastic methods include the Monte Carlo method (MCM), the harmonic decomposition technique, and the randomized MEDS (RMEDS). Experimental Frequency non-selective channel models are developed with Extended Suzuki process of type I, extended Suzuki process of type II, Loo’s model, Lutz’s model, and M-state Markov’s model. WSSUS Model and the COST 207 model are considered for frequency selective channels. MIMO channel models included the one ring scattering

Model, the two ring scattering Model and the elliptical MIMO model. Parameterization is done by the above mentioned methods. Results and Discussion The results included level crossing rates, the average duration of fades, auto correlation functions (ACFs), Cross correlation functions (CCFs)and power delay profiles etc., along with those of the respective reference models for comparison and to evaluate the performance of each model. Conclusion The channel models are very useful to evaluate the performance of any communication system. It is built with user friendly help files for each program and also web interfaces in order to effectively interact with. User has to just select the scenario and the required parameters and the output gives the channel coefficients, and some important stochastic properties in order to judge and analyse the particular model. Acknowledgement I am very grateful to Prof. Dr. Matthias Paetzold and Mr. Alizera Bohanifor their help and encouraging words during the internship.

20

National Institute of Technology Durgapur, INDIA Students’ International Research Projects Technical Report; Volume 3, 2011

21

USING STATIC OPTIMIZATION TO GUIDE DYNAMIC ROUTING AND WAVELENGTH ASSIGNMENT IN WDM NETWORKS

Aurijoy Majumdar

Third year B. Tech student, Department of Electronics and Communications Engineering National Institute of Technology Durgapur, INDIA

Telecommunications Field of Study

School of Engineering & Technology, Asian Institute of Technology, Thailand May 15 – July 15, 2011

Abstract A technique was developed for the RWA problem in WDM networks when traffic is dynamic. Here we use static optimization to guide dynamic routing and wavelength assignment in WDM networks. Most of the attention is devoted to developing and examining the Design Based Routing heuristic. Introduction Current optical backbone networks employ wavelength division multiplexing (WDM) in order to support a large amount of traffic. With WDM, the transmission bandwidth of each fibre is divided into multiple wavelength channels, which can be used to carry independent data streams. In addition to optical transmission, optical switching has been increasingly used to reduce the networks cost due to high speed electronic switching. Such a cost reduction is possible by allowing some traffic to optically bypass electronic switching at the nodes that are neither the sources nor the destination. Optical bypass of traffic introduces another dimension to the routing problem, not only a path must be found, a wavelength must be assigned to support each traffic stream. As a result the routing problem becomes the routing & wavelength assignment (RWA) problem. In Wavelength routed all optical WANs routing and wavelength assignment is a fundamental problem. The static RWA can be formulated as an optimization problem. To reduce the computational complexity of large problems we can separate the RWA into the routing and wavelength assignment problems. The result may be suboptimal compared to RWA in one step. However we have only used static traffic models so far, in the future when

Gbps applications become more common and traffic in the backbone becomes more bursty, then dynamic traffic model should be used. There are several reasonably efficient heuristics for the dynamic RWA. One such approach for the routing heuristic is the Design Based Routing (DBR). Design based Routing tries to utilize prior knowledge in traffic demands or statistics to guide dynamic routing of connections. The main idea is to solve a routing problem based on the traffic knowledge. Each new traffic request is then supported using one of the paths previously found through optimization. If all the computed paths are not free, then DBR applies shortest path routing. If all fails, the new request is blocked. Scheme for formulating the DBR as an RWA problem Given information: 1) Network Parameters- Set of links, cost per wavelength channel in using a specific link, number of wavelength channels on a specific link. 2) Traffic Parameters- Set of s-d(source-destination) pairs (with non zero traffic), Call arrival rate (offered traffic) for each specific s-d pair , target upper bound on call blocking probability. 3) Path parameters- set of candidate paths for each s-d pair, set of all paths, set of paths that use a specific link. Variables that are used in the optimization: 1) no. of wavelength channels assigned on path variable. 2) total no. of wavelength channels assigned for s-d pair variable.

National Institute of Technology Durgapur, INDIA Students’ International Research Projects Technical Report; Volume 3, 2011 Objectives: The objective is to minimize the total cost of the wavelength channels that are assigned for DBR. Constraints: 1) Link capacity limitation 2) Definition of gs in accordance with Erlang Fixed Point Equations 3)Upper bounds on call blocking probability 4)Integer Constraints to make the ILP problem linear While formulating the DBR in the above discussion we have assumed the optical network to be opaque. Hence we can choose from a no. of heuristics for wavelength assignment such as First Fit, Random etc. For a more detailed discussion and performance of the DBR see Reference (1)[Elw+03]. Experiments Having formulated the DBR as an RWA problem we verify it for dynamic traffic and validate see Reference (4) [Kov+95] some previously obtained results and then finally check the efficiency of the DBR in the ring and the mesh networks Simulation Results Simulation was carried out using the python programming language together with the PuLP optimization package. We verified the results obtained from previous studies. We also achieved significant results on the efficiency of the DBR used on different network topologies. Acknowledgement I would like to thank my supervisor Prof. Poompat Saengudomlert, Telecommunications Field of Study, Asian Institute of Technology, Thailand for his guidance and invaluable motivation during the internship peroid. I would also like to thank Akhtar Nawas Khan, PhD Scholar Telecommunication Field Of Study Asian Institute of Technology, Thailand for his essential support during this internship project. Finally I am grateful to the Director NIT, Prof. G.K. Mahanti, Prof. Anup Bhattacharya, Prof M.C. Majumdar, Prof. Parthapratim Gupta

(Dean Research & Consultancy), Prof. S. Haldar and Prof. S.N. Sarkar (Head student Welfare & Placement) for providing their support at various stages.

Fig1:The Blocking Probability vs the no. of hops of a multihop path. References Most of the study materials used in the course of the internship were derived from the class notes of the course on Optical Networks provided by Dr. Poompat Saengudomlert. 1) A. Elwalid, D. Mitra, I. Sainee, and I. Widjaja, “Routing and protection in GMPLS networks: from shortest paths to optimized designs,” Journal of Lightwave Technology, vol 21, No. 11, pp.28282838, November 2003 2) B.Mukherjee, Optical WDM Networks. Springer, 2006. 3) H.Zang, J.P. Jue, and B. Mukherjee, “A review of routing and wavelength assignment approaches for wavelength-routed Optical WDM networks 4) Kovacevic and Acampora, 1995. On wavelength translation in all-optical networks IEEE.

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FIRST PRINCIPLES INVESTIGATION OF THE ADSORPTION OF DIFFERENT MOLECULES ON Cu (011) SURFACE

Prateek Mehta

Final year B. Tech. student, Department of Chemical Engineering National Institute of Technology Durgapur, India

Department of Chemical Reaction Engineering

Hamburg University of Technology (TUHH), Germany May 25 – August 3, 2011

Abstract Density functional theory (DFT) and dispersion force corrections have been used to study the adsorption geometries, the bond formation and the electronic structures of phosphorine, 1,3-diphosphorin and 1,3 diarsinine di-carboxylic acid (PhDA, Ph2DA and As2DA respectively) on Cu (011) surface. At high coverage, all molecules adsorb with the molecular axis perpendicular to the surface, and the carboxylate group binds to the first layer of Cu atoms in a bridge position. The most important structural property is the orientation of the H atom in the vacuum exposed COOH group. This determines the possible reactions that the adsorbed molecules can get involved in and also has a decisive impact on the system’s work function. Simulation of the STM images help to experimentally identify the conformation of the adsorbed molecules. Introduction The adsorption of organic molecules on metal surfaces has been a subject of great scientific interest for many decades. This interest is justified because substantial knowledge of the process is required in the development of various electronic devices such as biosensors and biomaterials, diodes, transistors, etc.[1, 2]. The chemisorption of different conformers of PhDA, Ph2DA and As2DA on Cu(011) surface in an upright position [3,4] has been investigated, see Fig 1. Various positions of the hetero-atoms (P or As) in the aromatic ring and for the COOH H atom have been explored in order to reveal their impact on the thermodynamic and electronic properties of the concerned systems. The ability to present a variety of terminal functional groups makes it possible to obtain precise control of the structure of the surface at the molecular level,

and thus to control the interfacial properties of these organic surfaces. Computational Details In order to identify the most stable radical conformers, first-principles total energy calculations have been performed using the gradient corrected (PBE) DFT as implemented in the Vienna ab initio simulation package (VASP).

Fig 1: The 3 investigated systems- PhDA, Ph2DA and As2DA adsorbed on Cu surface. The adsorbed systems have been modeled by using a periodic supercell of 35.000×5.142×3.636 Å3. The equilibrium geometry has been assumed to be reached when the forces on the relaxed atoms of the system were less than 0.025 eV/Å. An energy cutoff of 625 eV has been used. Results and Discussion Thermodynamic Properties: Van der Waals interactions often contribute significantly to the heat of adsorption. A drawback of all GGA functionals, is that they cannot describe long-range electron correlations that are responsible for the van

23


24

der Waals forces. For calculating the dispersion interactions the Grimme method and the Ewald summation have been used [5]. In Table 1, the dispersion energies and their impact on the PhDA, Ph2DA and As2DA systems is shown. Even for chemisorbed systems, these dispersion interactions play an significant role, representing a quarter of the total energy of the system. Structure EPBE EDISP ETOTAL PhDA- V07N2C -3.68 -1.23 -4.91 Ph2DA- 393 -2.83 -1.29 -4.12 As2DA -393 -2.88 -1.51 -4.39 Table 1: Total Energy (ETOTAL) calculations for the most stable conformers of the three systems. EPBE is the electronic energy and EDISP is the van der Waals dispersion energy. Electronic Properties: The total work function has been found to change by about 2.14 eV when changing the H orientation. For an H-up oriented molecular layer it is 4.70 eV, while for an H-down oriented molecular layer is 6.84 eV. This is quite an interesting result as a lot of work is put nowadays in finding efficient ways for the in-situ variation of the system work function. In contrast to the large variation of the work function, the H position (up or down) does not in any way influence Cu-O bonds. Charge-transfer calculations between the two sub-systems (molecular layer and Cu surface) show that, regardless of the H position, the charge transfer from Cu surface toward the binding COO group is around 0.25 electrons. Therefore, the H atom position provides a way to engineer the surface work function without altering the interface characteristics. Investigation of the local density of states plots have revealed that increasing the number of hetero-atoms in the aromatic ring leads to a shrinkage in the HOMO-LUMO gap. The gap is almost half for Ph2DA and As2DA systems (0.65 eV) when compared to PhDA systems (1.2 eV). This gap has previously been found to around 3.5 eV when no hetero-atoms are present in the aromatic ring, i.e., for the terepthalic acid molecule. A smaller HOMO-LUMO gap indicates that these systems can potentially have better opto-electronic applications. Through the simulation of Scanning Tunnelling Microscopy (STM) images, it can be seen whether one can distinguish by such an

experiment the various possible adsorbed configurations. These simulations have revealed that: • different positions of the COOH hydrogen

atom lead to different orientations of the entire COOH group;

• for the structures with the H atom pointing down, the COOH group is oriented along the [01-1] direction;

• for the structures with the H atom oriented upwards, the COOH group is along the diagonal of the unit cell, see Fig 2.

Fig 2: STM images for the PhDA H-up conformer. References [1] Q. Chen, D.J. Frankel, N.V. Richardson, Surf. Interface Anal. 32, 43 (2001). [2] I. I. Oleynik et al Phys. Rev. Lett. 96, 096803 (2006). [3] D. S. Martin, R. J. Cole, S. Haq, Phys. Rev. B. 66, 155427 (2002). [4] D. C. Tranca, F. J. Keil, J. Chem. Phys. 134, 104708 (2011). [5] T. Kerber, M. Sierka, J. Sauer, J. Comput. Chem. 29, 2088 (2008). Acknowledgement I would like to thank the entire Department of Chemical Engineering, NIT Durgapur for granting me permission and providing me with a strong foundation to pursue this project. I also sincerely express my gratitude to Prof. Dr. F. J. Keil and Dr. D. C. Tranca for inviting me to work at the Department of Chemical Reaction Engineering, TUHH, and supporting me throughout the duration of my stay. I am immensely indebted to NIT Durgapur and TUHH for the financial support they provided to make this project possible.


25

DEGRADATION OF DCAN IN DRINKING WATER SAMPLE

Argha Namhata Final year B. Tech. student, Department of Civil Engineering


Department of Civil & Environmental Engineering University of Massachusetts, Amherst, MA USA

May 18 – July 19, 2011 Abstract

An investigation of the decomposition of dihaloacetonitriles (DHANs) in water solutions and fortified drinking water samples was conducted. The dichloroacetonitrile, bromochloroacetonitrile and dibromoacetonitrile concentrations were determined by a gas chromatography-mass spectrometry (GC-MS) method at regular time intervals and dierent temperatures. The effect of sodium thiosulfate (Na2S2O3), which is used as a preservative in water samples, was also examined. The rates of decomposition were determined for each compound. The results show that the reactions are faster in drinking water samples than in ultrapure water solutions. They are also favored at higher temperature, especially when sodium thiosulfate is present. The highest decomposition rate is shown by DCAN, followed by BCAN and DBAN, while at the presence of sodium thiosulfate the decomposition of DBAN is the fastest.. Introduction

Addition of chemical disinfectants to drinking water produces a wide range of organic disinfection byproducts. When chlorine or chloramines are used, a certain fraction of the disinfection byproducts (DBPs) will contain halogen atoms. Human health concerns have led to regulations in the US for two groups of these compounds: the trihalomethanes (THMs) and the halo acetic acids (HAAs) (Pontius, 1999). While many other halogenated byproducts have been identified in chlorinated waters (e.g. Richardson, 1998), most have not been widely quantified in actual drinking waters. Perhaps the only two non-regulated compound groups that have been widely measured are the haloacetonitriles, and the haloketones. The haloacetonitriles (HANs) include

dichloroacetontrile, trichloroacetonitrile and their brominated analogues. Results

A GC-MS chromatogram of DHAN solution 50 ug/l in ultrapure water is presented in Fig. 1.

Decomposition of DHANs was observed at 35°C, slower at 21°C and almost not at all at 4°C during the 96 h of analysis as is presented in Fig. 2(a)-(c), respectively. Decomposition rate was significantly faster in drinking water than in ultrapure water as it can be seen in Fig. 3(a) and (b), especially when sodium thiosulphate was present in Fig. 2(a). The fastest decomposition rate was that of DCAN, followed by BCAN and DBAN without addition of sodium thiosulfate, as it can be seen in Figs. 3(b) and 4. However, when sodium thiosulfate is present, DBAN decomposes with the fastest rate followed by DCAN and BCAN (Fig. 2(a) and (b)).


26

Decomposition Pathways

Proposed Mechanisms for the Degradation of

DCAN (summarized from Le Cloirec and Martin, 1985; and Peters et al., 1990).

Conclusions

DCAN degrades in the absence of chlorine by base-catalyzed and neutral pathways.

The former dominates above pH 7, and the latter below pH 6.5. In the presence of free chlorine, DCAN degradation can be much faster. This third degradation pathway probably involves hypochlorite as a catalyst. The acceleration due to chlorine is observed from about a pH of 6 to 8.5 under low to moderate chlorine residuals. The features of Dichloracetonitrile formation are consistent with expectations based on a presumed proteinaceous precursor. This byproduct is slowly formed over a period of hours to days. Its formation is strongly dependent on the chlorine concentration. The reactions are faster at higher pH, and continue at a nearly constant rate long after the THM and HAA forming reactions have become essentially exhausted. Acknowledgments

I would like to thank NIT Durgapur and also NITDAA for the support I received for the Summer Research. Also I wish to thank the National Science Foundation & American Water Works Association (AWWA) for financial support.


27

EXPERIMENTAL STUDY OF OXYGEN ENHANCED PREMIXED COUNTERFLOW FLAMES: EFFECT OF DILUENTS AND

REACTANT PREHEATING

Swadesh Pal Final year B. Tech. student, Department of Mechanical Engineering


Laboratoire de Combustion ET de Detonique, CNRS, ENSMA, University of Poitiers, FRANCE

10 May – 19 July, 2011

Objective The work presented here aimed initially at designing and evaluation of a new energetic process leading to the reduction of the energetic cost for CO2 capture in post-combustion at the exhaust of gas turbines or furnace. The study was devoted to the study of thermal, chemical and aeronautical phenomena of the new combustion regimes in which the chemical reaction is highly diluted in combustion products. The principle of this new technology is twofold:

i. Increase of the CO2 concentration in the combustion products to allow transportation and sequestration with minimal energy consumption i.e. by reducing the energetic cost of the CO2/N2 separation;

ii. Control of nitrogen oxides (NOX) and unburnt compounds emissions.

Experimental Setup Counterflow Burner System A counterflow burner has been designed and realized, it consists of two identical vertically opposed nozzles. The premixed mixture (CH4/O2/N2/CO2) is injected in the bottom burner and the diluents (CO2/N2) in the top burner. The separation distance (H) between the nozzles of the counter flow burner can be changed but equals to 24 mm in this experiment. An annular concentric co-flow of nitrogen is established to provide a curtain in order to prevent the reaction of fuel with surrounding air. The flow on each side is electrically preheated up. Thermocouples and flow meters are used to fix the operating conditions of the experiments.

Counter-flow Burner Snapshot & Schematic Diagnostic Methods

OH-PLIF Schematic Image Processing The behaviour of the flame is characterized by the variation of the flame thickness δ0 and position between the two opposed burners. Visualization of the reaction zone by OH-PLIF allows localizing combustion reaction zone. Transient locations of the reaction zones can be identified by radical distributions such as OH using OH-PLIF Technique. Images are collected in the direction orthogonal to the laser sheet, providing black-and-white measurement on a 646×1022 pixels matrix. Data from the PLIF (Planar Laser Induced Fluorescence) measurement technique contain sequences of 200 Frames each. They are in the format (*.SPE). The size of the Data Set is 55.8 GB.


28

The image processing algorithm was operated on a minimum of 200 images with Code::Blocks Platform as Compiler and using the Simple Library for Image Processing (SLIP) developed by Institut Pprime - CNRS, Poitiers; it consists to calibrate the position of the burner mouths, to determine the OH emission zone in order to reduce the processing time, to spatially filter; to identify the maximum of the OH emission, to threshold the image before to extract the OH zone thickness. The threshold is accurately determined from the method of least squares to fit the experimental OH emission profile with a Gaussian distribution. The reaction zone outline is then extracted as the wideness at the inflexion point level of the normal distribution. Results and Discussions

Premixed Flame Snapshot

i. Although the increase in diluents concentration makes the flame less stable but preheating of reactant broadens the flammability domain. Compare with N2, much CO2 in the diluents decrease the flame stability.

ii. The flame thickness decreases with the increasing strain rate also with the increase of diluents CO2/ (CO2 + N2).

iii. The increase in equivalence ratio of the fuel-air mixture shows an increase in the flame thickness.

iv. The flame position from top burner decreases with the increase in concentration of diluents CO2/ (CO2 + N2).

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 10.16

0.17

0.18

0.19

0.2

0.21

0.22

X*

XO2

Tt = 294 KTt = 623 KTt = 723 K

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 11.5

2

2.5

3

3.5

X*

Flam

e Th

ickn

ess,

δ0

strain rate = 16.67 s-1strain rate = 20.83 s-1 strain rate = 25.00 s-1 strain rate = 29.17 s-1strain rate = 33.33 s-1

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 11.5

2

2.5

3

3.5

X*

Flam

e Th

ickn

ess,

δ0

φ = 0.9φ = 1.0φ = 1.1

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 110

12

14

16

18

20

22

24

X*

Flam

e Po

sitio

n, P

(mm

)

strain rate = 16.67-1strain rate = 20.83 s-1strain rate = 25.00 s-1strain rate = 29.17 s-1strain rate = 33.33 s-1

Conclusion The flammability study and the reaction zone structure are investigated under various fuel-air mixture concentrations, preheated temperature, strain rate, and diluents composition. The OH-PLIF is used to analyze the reaction zone thickness in the premixed combustion in details. Further Particle Image Velocimetry (PIV) will be used to observe interdependency between the flame thickness and mixing layer thickness. Later an optimized database of the obtained experimental data will be created that can be used in industries for designing better energy efficient burners with low emissions.

Acknowledgement I would like to extend my gratitude to Prof. Jean Michel Most, Director of Research, CNRS to provide me with an opportunity to work under his guidance and providing me with the sufficient funds. I would like to thank Dr. Sachin Dahikar, Damein Denis and Alain Claverie for helping me to perform the experiments and to understand the project. I would also thank Ms. Jocelyne BARDEAU for escorting me at Poitiers, FRANCE. Lastly, I would like to extend my sincere thanks to my Institute, NIT Durgapur for allowing me to pursue the internship and providing an aid

r it. I am highly grateful to Prof. P. P. Gupta (Dean Research & Consultancy) for providing continuous support.

fo

Variation in flame position, P ) from top burner for tant equivalence ratio,

and temperature but for different strain rate (i.e. different velocity) with increasing volume fraction of

2 (X*) in diluents (CO2 + N2)

Variation in flame thickness, δo (mm) for constant velocity and temperature but for different equivalence ratio, with increasing volume fraction of CO2 (X*) in diluents (CO2 + N2)

Variation in flame thickness, δo (mm) for constant equivalence ratio, and temperature but for different strain rate (i.e. different velocity) with increasing volume fraction of CO X*) in diluents (CO2 + N2)

Extinction limit as a function of CO2 volume fraction (X*) in diluents (CO2 + N2) for constant velocity, equivalence ratio and but for different preheated temperatures of diluents (CO2 + N2)

(mmcons

CO

2 (

http://sn131w.snt131.mail.live.com/mail/


DEVELOPMENT OF TRIPLE GEM DETECTORS AND COSMIC RAY STAND FOR CMS EXPERIMENT

Rajesh Pandey

Final year B. Tech. student, Department of Computer Science and Engineering National Institute of Technology Durgapur, INDIA

Department of Physics

European Organisation for Nuclear Research (CERN), Geneva, Switzerland May 29 – July 22, 2011

Abstract The work carried out within the framework of this internship deals with the 1. Development of triple GEM detectors and BEAM testing with data acquisition in with magnetic field as high as 2.5 T and tilt up to 30 degrees and 2. Development of Cosmic Ray stands for CMS. Introduction The GEM invented by F. Sauli, consists of a thin polymer foil (Kapton1), metal-coated on each side, perforated by holes arranged in a high density hexagonal pattern (100/mm2). Applying suitable potential between the two sides, each hole acts as an individual proportional counter, multiplying the electrons released by the ionizing radiation in a gas, which enter the holes. The electrons of the avalanche coming out from the holes can be driven to another GEM foil for further multiplication or be collected by readout electrode.

Fig: The Electric lines of force through the GEM holes

Potential Divider for TRIPLE GEM The different GEM plates of a detector need different voltage supply hence are given a single supply to all the 3 plates using a divider. High resistors, of the order of MΩ are used, so that the divider current is limited to maximum 800uA. With a voltage of 4kV on the divider, the voltages for each GEM plate and the drift are calculated. Data Acquisition: Gas parameters:

• Tracker line flow: 4.5l/hr • Detector flow: 4l/hr • Ar:CO2:CF4 mixture ratio: 45:15:40

29

National Institute of Technology Durgapur, INDIA Students’ International Research Projects Technical Report; Volume 3, 2011 The parameters that were varied in the data taking are as follows:

Latency was varied in the set [20,40,50,60].MSPL was varied as [1,2,3] clock periods. Voltage on the detector was varied over six points from 4 kV to 4.5 kV. Magnetic field was varied from 0 to 2.5T.Mid-Eta runs were taken at 30k events and High-Eta runs at 10k events with long runs up to 160k events. The detector was tilted to 30 degrees. We varied the voltage in the presence and absence of magnetic field. And the Lorentz angle was measured at 4.5kV in presence of magnetic field with and without tilt of 30 degrees. HV scan was also done with and without TIMING GEM. Development of Cosmic Ray Stand: A scintillation detector or scintillation counter is obtained when a scintillator, consists of a transparent crystal, usually phosphor, plastic or organic liquid is coupled to an electronic light sensor such as a photomultiplier tube (PMT) or a photodiode. PMTs absorb the light emitted by the scintillator and reemit it in the form of electrons via the photoelectric effect. The subsequent multiplication of those electrons (sometimes called photo-electrons) results in an electrical pulse which can then be analysed and yield meaningful information about the particle that originally struck the scintillator. Our scintillator is made up of polystyrene with 1% dopants. It was coupled with Hamamatsu PMT using an aluminium cover which acts as magnetic shield. We supplied the high voltage -1750 volts to create high electrostatic field to attract the electrons. On passing of the cosmic rays through the scintillators the obtained signal was made to enter into the discriminator. We set threshold to -100 mill volts to neglect the noise in the signals and noted the counts (no. of high energy particles in the PMT) for each 100 seconds. After that the signals produced by the photomultiplier were analysed with the help of an Oscilloscope (Le Croy Wave Runner 104 MXi-4). In a chosen window we note down the energy of the curve formed (in nVs) and also analyse the histograms showing no. of particles with particular energy.

For each of the scintillators we have done the experiment twice with and without a black paper. We have used the black paper between the scintillators and PMT while taking the data to know the thermal effect and electronic noise. For black paper we used non-conducting paper (kapton) wrapped with black tape. Due to the strong electrostatic field some electrons from the black paper were too attracted. This is the reason why we had >0 counts with black paper (ideally it should have been zero). Conclusion: The HV scan was done for 6 points and the efficiency of Timing GEM as well as that of tracker GEMs were obtained for each point. The mean, RMS, efficiency and space resolution are noted. Beam profile for each detector is obtained using root from the VFAT data. The response of the detector was highly efficient and the beam test was a success. The scintillator counter showed almost ideal behaviour with and without black paper. The value for different scintillators was taken and on the basis of that we can judge their efficiency. Acknowledgement: I would like to express my heartfelt gratitude to everyone with whose support and guidance I was able to attend the Summer Students Programme 2011, CERN. First and foremost to The Director, NIT Durgapur, for his positive response towards the program and giving me permission to attend this unique event, I express my sincere gratitude. Also, many thanks to Dr. N. K. Roy and Dr. P. Kumbhakar of NIT Durgapur for the constant support and guidance throughout. I would thank Dr. Archana Sharma, CERN and my supervisor Mr. Andrey Marinov for their invaluable guidance and supervision during the course of this project. I wish to wholeheartedly thank to all my colleagues and friends at ISR and RD-51 labs, CERN who guided me and taught me all about the activities and research going on.

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National Institute of Technology Durgapur, INDIA Students’ International Research Projects Technical Report; Volume 3, 2011 EFFECT OF THE VO2 PHASE TRANSITIONS ON THE OPTICAL AND

ELECTRICAL PROPERTIES OF ZnO

Monica Priyadarshini Final Year B. Tech. Student, Department of Electrical Engineering


Nanoscience & Nanotechnology Initiative (NUSNNI), National University of Singapore, Singapore

30th May-28th June 2011 Abstract In the next generation of solid state devices, such as field effect switches, optical detectors, nonlinear circuit components, and solid-state sensors, multifuncationality of a material will play an important role. Since VO2 undergoes strong phase transitions near room temperature (~340K) it is of great interest. Changes in the properties of ZnO grown on top of VO2 are observed. The main objective of this work is to study optical properties of ZnO film grown on top of VO2. In this work, pulsed laser deposition technique is used to get high quality thin films. Temperature dependent PL results show abrupt change in intensity and peak shift near MIT of VO2. Electrical properties are also studied in the PPMS. Introduction MITs are transitions from a metallic to an insulator. MIT is a great area of research that covers a multitude of systems and materials. In particular, certain transition metal oxides exhibit such phase transitions and among these, the vanadium oxide family (VO2,V6013,V2O3) shows the best performance, presenting noticeable resistivity change between two phases. Among these oxides, the transition temperature (TMIT) of VO2 is close to room temperature (~ 340 K).

Theory Different types of MIT:

Mott- Hubbard Transition – for materials that become Mott insulators. The metal-insulator transition (MIT) can be achieved by varying the distance between the atoms in the crystal.

In transition-metal compounds, the MIT can be achieved by tuning various parameters: In undoped compounds due to rising temperature, rising pressure or varying compositions. In the case of doped compounds the MIT can be achieved via changing the concentration of donors or acceptors.

Disorder-induced MIT can also be achieved by doping the compound or increasing the disorder in a given material (Anderson MIT).

Metal Insulator Transition can be triggered by different excitations:

• Thermal Triggering • Electrical Triggering • Optical Triggering • Magnetic Triggering • Strain Triggering

31

National Institute of Technology Durgapur, INDIA Students’ International Research Projects Technical Report; Volume 3, 2011 Experimental Results and Discussion Temperature dependent PL measurement of ZnO/VO2/Al2O3 film is performed. At first, temperature is raised from room temperature (300 K) to 380 K. At different temperatures PL spectrum is observed.

350 400 450 500 550 600 650 7000

200000

400000

600000

800000

350 400 450 500 550 600 650 700

Inte

nsity

(a.u

)

300 K 320 K 340 K 360 K 380 K 400 K

Al2O3/VO2/ZnO

Wavelength (nm)

Sudden drop in the intensity of PL spectra can be observed near the phase transition of VO2.

In Low temperature PL data, till 100K central frequency is constant. At 150K there is a shift in central frequency, this might be due to the presence of V2O3 or V6O13 in VO2 Since transition temperature of both of them is near 150K. Electrical Measurement: This measurement is performed in the Physical Property Transport Measurement System (by Quantum Design).Resistivity vs temperature curve for ZnO/VO2/Al2O3 film is plotted.

2 0 0 2 5 0 3 0 0 3 5 0 4 0 01 E - 4

1 E - 3

0 .0 1

Res

istiv

ity (Ω

-cm

)

T e m p e r a t u r e ( K )

H e a t in g

Conclusion Temperature dependent PL provides some exciting results near transition temperature of VO2, V2O3 as well as V6O13. Hysteresis loop is obtained near the transition temperature of VO2 in the resistivity vs temperature curve of ZnO/VO2/Al2O3 film. These results show that ZnO/VO2/Al2O3 film will be very useful for opto-electronics. Acknowledgement First and foremost, I would like to thank my advisors Prof. Venky Venkatesan and Prof. Ding Jun for giving me such an opportunity. They provided for my accommodation, air fare and paid me $600 as allowance to manage my stay. I am also very grateful to the Professors of my department for their kind and patient support. And last but not least, I thank my parents and my friends for their continuous support and encouragement. Key words: MIT – Metal Insulator Transitions TMIT – Transition Temperature PLD – Pulsed laser deposition PL – Photoluminescence PPMS – Physical Property Transport Measurement System

C o o l in g

High Temperature PL

350 400 450 500 550 600 650 7000.0

5.0x106

1.0x107

1.5x107

2.0x107

Inte

nsity

(a.u

)

Wavelength (nm)

Low Temperature PL

10K 20K 50K 100K 150K 200K 250K

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National Institute of Technology Durgapur, INDIA Students’ International Research Projects Technical Report; Volume 3, 2011 DESIGN AND SIMULATION OF MATERIALS HANDLING TEST-BED

USING SYNCHRONOUS SEMANTICS OF TIMEME

Supriya Roy Final year B. Tech. student, Department of Computer Science & Engineering


Department of Electrical & Computer Engineering University of Auckland, New Zealand

May 18 – July 19, 2011 Abstract Embedded systems, designed to perform a few dedicated functions, often find applications in safety-critical environments such as automotive, aeronautics, and industrial automation etc. Such safety-critical applications require to handle concurrent and synchronous execution of tasks while effectively utilizing the available resources within the given time constraints. In this winter project, we worked with “TimeMe”, an Integrated Development Environment (IDE) for designing safety-critical embedded application, to design and simulate the “Materials Handling Test Bed”. Introduction TimeMe is an IDE used for designing safety critical applications which are based on IEC-61499 standards. An IEC-61499 is an open standard for distributed control and automation. A function block in the IEC-61499 standard is the basic building block from which complex and composite applications may be built. There are two types of function blocks: basic function blocks and composite function blocks. A composite function block contains other composite function blocks and/or basic function blocks. A basic function block is a small reactive unit with its own event-data association, algorithm(s) for data handling and an execution control chart (ECC) for state control. Each function block has event inputs and outputs as well as data inputs and outputs. In a basic function block the execution of an algorithm is triggered by the occurrence of an input event. The executed

algorithm then produces output data from the input data or event. When the algorithm has finished executing an output event is generated. This output event might then be the input event to another function block. The design of complex industrial systems such as baggage handling systems can be difficult because of large state-charts or complicated component interactions. Additionally, the flat state machines used in the IEC61499 standard do not provide a simple method for specifying error handling within the process’s execution. State machines from synchronous languages, however, have hierarchy and concurrent constructs to aid the developer. In TimeMe we use Hierarchical and Concurrent extension to ECCs (HCECCs), which presents new design constructs adapted from synchronous languages in order to improve system specification with function blocks. The semantics of HCECCs are backward compatible with the IEC-61499 standard. Materials Handling Test Bed Test Bed is an execution environment configured for software testing. It consists of specific hardware, network topology, operating system, configuration of the product under test, system software and other applications. Materials Handling Test Bed is built for the automation of the industrial procedure of handling the work-pieces and processing it to obtain the required product. TimeMe provides an interactive and easy to use environment for design and simulation of such applications. The Function Block compiler takes care of the task synchronization and concurrency issues in the background.

33

http://en.wikipedia.org/wiki/Open_standard

http://en.wikipedia.org/wiki/Open_standard

http://en.wikipedia.org/w/index.php?title=Distributed_control&action=edit&redlink=1

http://en.wikipedia.org/w/index.php?title=Function_block&action=edit&redlink=1

http://en.wikipedia.org/wiki/Algorithms

http://en.wikipedia.org/w/index.php?title=Execution_control_chart&action=edit&redlink=1

National Institute of Technology Durgapur, INDIA Students’ International Research Projects Technical Report; Volume 3, 2011 Experimental Setup The test bed consists of a series of FESTO Equipments, referred to as Stations, which work in sync with each other to process the work-pieces. They are as given below: Distribution Station Pick and Place Station O-Loop Conveyor Input L-Conveyor Processing Station Output L-Conveyor

The Composite Function block illustrating the Test bed is shown in figure 1.

Fig. 1 Composite Function Block illustrating

theTest Bed

The interconnections among the above Stations, the Input/Ouput events and the Input/Output variables required by each are illustrated in figure 2. The Input/Ouput data variables are basically the Sensors/Actuators required by the equipments.

Fig. 2: Interconnections among the Stations

Fig 3: The Materials Handling Test Bed

Conclusion TimeMe provides a platform for advanced development of safety-critical embedded applications. The tool is industry-ready and has added some extra desirable features than the current industrial softwares such as nxtStudio. It is sure to radically improve and ease the industrial automation design systems. Acknowledgement I would like to thank Dr. P S Roop for hosting me as an intern and giving me this wonderful exposure. I convey my gratitude towards NIT Durgapur and MHRD (Govt. of India) for partially funding and making this internship possible. Thanks to Zeeshan, Gareth, Omar and Jeffrey Yan.

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THE TRANSPONDER DATA RECORDER: FIRST IMPLEMENTATION AND APPLICATIONS

Soumen Samanta

Final year B. Tech. student, Department of Electronics & Communication Engineering National Institute of Technology Durgapur, INDIA

DISP and Vito Volterra Centre

Tor Vergata University; Via del Politecnico, 100133 Rome, Italy

Abstract The Transponder Data Recorder is an experimental 1090 MHz signal acquisition system designed by the Radar and Navigation group at Tor Vergata University to record the signals in the Secondary Surveillance Radar band, centered at 1090 MHz. The peculiarity of the receiver is that it is based on five receiving chains (4 linear chains with large dynamic range and one with a logarithmic receiver) connected to a wideband linear array antenna. The TDR was developed in order to analyze the channel traffic and to test the new signal processing algorithms, in the research frame on multilateration (MLAT) and Automatic Dependent Surveillance (ADS-B), with real signals. Introduction Today the 1090 MHz channel, exploited first by the military IFF (Identification Friend or Foe) systems and then by the secondary surveillance radar (SSR), is widely used for air traffic (but also in airport for vehicular traffic) surveillance. In this context there are many applications that use the 1090 MHz signals. Some of these, such as ADS-B and Multilateration, are becoming increasingly important within the air traffic control, and may integrate or, in some cases, replace the SSR radar stations. For these reasons the integrity and the efficiency of these systems have become very important. In a typical high-density airspace, an increasing number of transponders (airborne or vehicular) transmit signals at 1090 MHz, either as replies to the SSR stations (conventional and Mode S), or spontaneously ('Squitter'). Also in the future the burden of the channel may be increased by the TIS-

B stations, which provide information on non-ADS-B aircraft using Mode S signals. In order to reduce the effects of receiving superimposed signals from different sources, we studied signal processing algorithms, useful to discriminate and separate overlapping sources; some of these algorithms need a multichannel receiver and an antenna array. Hence the need for a 1090 MHz signals acquisition system with appropriate characteristics, useful to evaluate the efficiency of the separation algorithms using the received signals, and also to compute traffic analysis and statistics. This paper presents a description of this system, called TDR (Transponder Data Recorder), complying with ICAO and RTCA requirements. The design of the antenna, the analogue front-end and the digital section as well as the results from the first use of TDR, with the analysis of the 1090 MHz channel around the experimental area are presented. Moreover we analyze the signals density and present the statistics of each signals type (conventional, Mode S).Finally, we present the results of tests of the preliminary application of the separation algorithms on the recorded signals and the proposal for future work and conclusions Model The research requirements have driven the design of the TDR. In order to use decoding algorithms based on array processing, the selected type of the antenna is a uniform linear array, with 6 elements. The analog part is composed by four receiving chains, connected to the four central elements of the array, and one logarithmic receiver connected to a side element of the array (the other side element is connected to a 50 Ohm load). The logarithmic channel is to be used for (a) Reply detection, (b) Evaluation

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National Institute of Technology Durgapur, INDIA Students’ International Research Projects Technical Report; Volume 3, 2011 of compliance of the pulse. The digital section must sample the channels with a shared clock, and it has to reach high sampling rate (up to 100 MS/s) to perform the better phase estimation between the channels. The analog section has a dynamic range of 70 dB. The low-noise amplifier permits a good noise figure (0,8 dB) and a total gain of 60 dB. The RF filters are Surface Acoustic Wave type (SAW), with a bandpass of 50 MHz. The IF (Intermediate Frequency) is 25 MHz and the output of the IF section is filtered with a band-pass filter and a DC-block. The variable attenuator (in steps from 0 dB to 16 dB) is useful to shift the dynamic range in order to use the TDR in an aeroportual area. The digital section for the whole system provides a high sampling rate, up to 100 Msamples/s with a 14 bit resolution. To acquire the linear channel directly at IF the sampling frequency is set at 100 M samples/s. It is based on the NI PXI 1082 controller. There are three acquisition cards by National Instruments (NI PXI 5122), with two analog input channels each.

Experimental Using the TDR prototype, connected to one element of the antenna, it was possible to record the data stream (at 10 Msample/s) to perform a channel traffic analysis. The results allow traffic statistics related to the area around the installation site. The antenna was positioned in Tor Vergata University on the Engineering Faculty building roof, as shown in figure 7. The location is near Rome, close to Ciampino airport and 30 Km away from the International airport of Fiumicino. The recording session was developed on Thursday 14th April 2011 at 01 p.m. Up to 10 data streams of 1 s was recorded time continuously. The starting time of each acquisition was chosen random in order to avoid synchronization with the traffic due to ground radar interrogations. An analysis of the received signals power, considering the receiving chain gain, the antenna gain and the transmitting power, permits to obtain the range distribution of aircraft, which transmitted the received signals. The percentage of Mode S signals over all the received signals is 8%. A percentage of 8.5% of the Mode S replies

are affected by interference with other signals. To better understand these results, it is possible to note that the probability to receive a 1090 squitter (ES) free of interferences using an omni-directional receiver, is estimated by a poissonian model with λ (FRUIT rate) equal to the inverse of the average number of received messages per time : PES(0)=exp(−λtES)= 0.93 Where tES = 120 μs, λ= 1026 s-1. Hence the estimated probability to receive garbled Mode S signals is 7%, the value being close to the experimental rate. An exhaustive measurements campaign, at different time each day, permits to evaluate the channel traffic density near Rome. This earlier result shows that although the FRUIT rate is low, the probability to receive interfered mode S signals is not negligible.

Results and Discussion The transponder data receiver (TDR) is a multi-channel system useful to receive, record and process 1090 MHz signals from airborne and vehicular transponders (Mode S and conventional). It is composed by a six patch elements array antenna, connected to the 4 linear channels and to a logarithmic receiver. The digital section is based on NI technologies. The TDR system was designed in the research frame on the ADS-B/MLAT to develop and test new signal processing algorithm, and to analyze the 1090 MHz channel traffic. Actually a prototype system based on a single channel receiver is operative at Tor Vergata University. The prototype is composed by a single RF channel divided into a linear channel, directly sampled at the IF of 21,5 MHz, and into a logarithmic channel used as signal detector.

Conclusion The prototype permits to obtain a first channel traffic analysis and the evaluation of PASA algorithm, useful for mixed signal separation using a mono-channel receiver. The first results are encouraging to continue the studies and are helpful for the definitive TDR version dimensioning. Acknowledgement NIT-Durgapur Radar Lab, Tor Vergata University

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37

CALIBRATION OF FIELDS IN DEVELOPMENT OF TRIPLE-GEM DETECTOR AND BEAM TEST IN MAGNETIC FIELD

Esha Sarkar

Final year B. Tech. student, Department of Electrical Engineering National Institute of Technology Durgapur, INDIA

Department of Physics

European Organisation for Nuclear Research (CERN), Geneva, Switzerland May 29 – July 22, 2011

Abstract The work carried out in the internship is the study of development of Triple GEM detectors and the data acquisition in with magnetic field as high as 2.5 T and tilt up to 30 degrees. The steps involved in carrying out the work were development of triple GEM detector followed by initial current and voltage measurements that led to calibration of fields in different regions in the detector and finally the data acquisition changing different parameters like the tilt, magnetic field and defining the length of the run by changing the number of events. Data were collected also changing the voltage to six different points and time distribution curves were noted Introduction Multiwire Proportional Chamber(MWPC) used avalanche multiplication of electrons as the muon beam hits the gas. MWPC revolutionised the area of particle detection allowing fast detection and localisation of small amount of charge released following ionisation. But certain limitations in rate capability, granularity and the repulsion between anode wires when held few millimetres apart were becoming conspicuous. This led to the development of MicroStrip Gas Chambers (MSGC) but again it faced the similar rate limitations. Also, polymerisation in the gas resulted in deposition of thin insulating layers on the electrodes and discharges caused by imperfections in photolithography caused low performance. Gas Electron Multiplier (GEM) is the most recent development in the Gas-based detectors genre which operates below the critical voltages for discharge making it more reliable. Single GEM has an appreciable amount of

discharges. Thus, for High Eta upgrade Triple GEM is opted for. Design and Construction of Triple-GEM General construction: The Gas Electron Multiplier (GEM) consists of a thin, metal-clad Kapton layer chemically perforated by a high density of holes (100/mm2).

Fig 1: The Electric lines of force through the GEM holes Potential Divider configuration for the GEM -foils: The voltage divider configuration of the Triple GEM detector consists of supply which is distributed among different layers through optimal resistances. The detector is made through this configuration to avoid transverse flow of current and avoid discharge. The lengths of each layer are: Drift region:3mm Transfer region1:1mm Transfer region2:2mm Induction region:1mm

National Institute of Technology Durgapur, INDIA Students’ International Research Projects Technical Report; Volume 3, 2011 Fig: Potential divider configuration Fig 2: Potential divider configuration

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Current vs Voltage

0

1

2

3

4

5

6

3400 3500 3600 3700 3800 3900 4000 4100

Voltage(V)

Curr

ent(u

A)

Series1

Fig 3: After the configuration was implemented, the current v/s voltage relationship Data Acquisition: Gas parameters:

• Tracker line flow: 4.5l/hr • Detector flow: 4 l/hr • Ar:CO2:CF4 mixture ratio: 45:15:40

The parameters that were varied in the data taking are as follows:

• Latency: it was varied in the set [20,40,50,60]

• MSPL: it was varied as [1,2,3] clock periods

• Voltage: voltage on the detector was varied over six points from 4 kV to 4.5 kV

• Magnetic field: varied from 0 to 2.5T • Events: Mid-Eta runs taken at 30k

events and High-Eta runs at 10k events with long runs up to 160k events

• Tilt: the detector was tilted to 30 degrees

Different types of data collection:

1. HV Scan: Varying the voltage with or without the magnetic field

2. Lorentz angle measurement: keeping the voltage at 4.5kV in a magnetic field with or without a tilt of 30 degrees

3. HV Scan after detector is flipped 180 degrees

4. HV Scan with and without single mask detector

5. HV Scan with and without Timing GEM

Conclusion High Eta Upgrade is being performed at RD 51 at a field as high as 2.5T. The detector has undergone a beam test and the efficiency curves plotted were very close to the simulated values. This way the GEM detectors will be able to detect the high rate of particles at very low value of theta i.e. very close to the beam axis which the RPCs are unable to handle. Acknowledgement I would like to thank Dr. Archana Sharma without whose support this internship would not have been possible. I would also like to thank my guide, Yasser Assran for successful completion of the project. My special thanks to Dr. N.K. Roy and Dr. P. Kumbhakar whose pioneering efforts made this dream internship possible. I would also like to thank the Director and Financial Committee of NIT Durgapur for sponsoring me for the internship.

National Institute of Technology Durgapur, INDIA Students’ International Research Projects Technical Report; Volume 3, 2011 DESIGN OF A CAR LIFT WITH PRO/ENGINEER USING TOP DOWN

DESIGN TECHNIQUE

Mohit Raj Saxena Final year B. Tech. student, Department of Mechanical Engineering


The College of Engineering American University of Armenia, Yerevan, Armenia

May 17 – June 28, 2011

Background Currently there are almost 500,000,000 cars hitting the roads and this number is estimated to grow. Number of cars is rising but number of car park space remains the same, which is the root of serious problems such as traffic, pollution and noise. Places where this issue is noticeable are near universities, offices and yards during evenings, when spaces are filled with cars and neighbourhood become crowded. Some solutions are given to this problem, such as individual parking garages. But there are many disadvantages with them and maximum space efficiency is not provided. For example ramps, which are never needed and used as a parking. The aim of the project is to provide more park space for vehicles, by doubling up the parking spaces, and at the same time to prevent cars from hitting, scratching and vandalism. Manufacturing a scaled down model of this system is also included in this project. Objective The goal of the project is to design a car lift system to be used in backyards, parking lots, squares in front of public/private buildings etc. It is a two level system that uses a 4-link mechanism to bring up (down) the car to (from) second level and also locate another car in the first level. During location, cars move (rotate) towards side direction, thus saving space in front and behind of the system. The cars should be located or removed on/from the pallets independently.

The main subsystems of the lift are: • Two pallets for upper and lower

levels; • Frame bearing the pallets and cars

through guides and • Hydro cylinders, which operate the

system.

4-link mechanism used in the lift Theoretical Background & Procedure An advanced CAD/CAM application Pro/ENGINEER is used to create the 3D model of the system which is also tested and simulated. Top-Down design technique allows you to control the dimensions and sizes of different parts of the system from a special sheet, called Layout. It also makes the process of creating parts and assembling them easier by the help of using references, which are published and copied from the general skeleton.

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National Institute of Technology Durgapur, INDIA Students’ International Research Projects Technical Report; Volume 3, 2011 Top-Down design technique consists of the following main steps: 1. Planning Session 2. Layout 3. Assembly Structure 4. Skeleton Geometry 5. Top-Down Verification Procedure that was followed during project, right from designing to manufacturing a scaled down model, can be summed up as follows: 1. Conceptual design The design of the model is developed conceptually. The overall sizes, functioning principles, drive types, their approximate locations and specifications are specified. The model is drawn manually and then inside Pro/ENGINEER. 2. Layout in Pro/E Names and dimensions of the parts that are determined in the previous step are inserted into Pro/ENGINEER and they must be connected with their 2D sketch. 3. Assembly Structure in Pro/E New empty components of part, subassemblies and assemblies are created inside Pro/ENGINEER which is defined manually in the first step.

4. Motion Skeleton in Pro/E By the help of sketch tools, the movement of the parts within the system is defined. In this step, sketches are also used as references for modelling and assembling. 5. Pro/E 3D modelling 3D modelling and assembling of all the parts is done inside Pro/ENGINEER. Acknowledgement I would to sincerely thank Prof. Sargis Zeytunyan for giving me the opportunity to work under his guidance in his lab and providing me with all the materials required.

I would also thank Sevak Mahmoodian, a Masters student, for his valuable suggestions during project, Tigran Hovannisyan and Tatevik Nasoyan for helping me in learning Pro/E, and Mariam Petrosyan for being a great companion; and all others who helped me with my project. I would also like to thank Sumit Kumar Bansal, Neeraj Kishore Pandey, Arin Balalian and Mane Grigue Voskerchian from the bottom of my heart for making my stay the best it could be. Lastly, I would like to extend my sincere thanks to my college, National Institute of Technology, Durgapur for allowing me to pursue the internship and providing me with sufficient funds.

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41

STUDY OF THE ELECTRONIC ASPECTS OF THE TRIPLE-GEM

DETECTOR

E. Vindhya Revathi Vyjayanthi Final year B. Tech. student, Department of Electronics and Communication Engineering


Department of Physics European Organisation for Nuclear Research (CERN), Geneva, Switzerland

May 29 – July 22, 2011

Theory Abstract

The basic element of the GEM detector is a thin, self-supporting three-layer mesh realized by the conventional photolithographic methods used to produce multi-layer printed circuits. We have obtained medium size meshes (5 by 5cm’) with 25 pm thick polymer sandwiched between 18 pm thick copper electrodes; the etching pattern has rows of 70 um wide holes spaced 100 um. Because of the etching process, holes are conical in shape from both entry sides, probably improving the dielectric rigidity. Inserting the grid between two electrodes, and upon application of suitable potentials, the electric field in a channel develops, for 200 V applied across the mesh; the external drift fields are 4 kV/cm. The calculation has been realized with the commercial program MAXWELL. From the data reported, we expect to obtain multiplication in the high field in the centre of the channel at a difference potential around two hundred volts; for this value, the corresponding field strength along the central line is shown in at the maximum, it reaches 40 kV cm-'.

GEM detector is the new era of particle detection. The work carried out during my internship involves study of the electronic aspects during the High Eta Upgrade of Triple GEM detectors. VFAT2 is the Integrated Circuit which helps to deal with the signal obtained after collision of Muon beams. A detailed study about the chip is discussed in the report along with the data taken by the chip. Introduction The Gas Electrons Multiplier (GEM) is a type of gaseous detector able to collect the electrons released by ionizing radiation, guiding them to a region with a large electric field, and thereby initiating an electron avalanche. The avalanche is able to produce enough electrons to create a current enough to be detected by the electronics. In most ionization detectors, the large field comes from the avalanche and guides them towards the readout electronics. The resulting electrons are ejected from the sheet and a separate system must be used to collect the electrons and guide them towards the readout.

Fig 1: The GEM Detector Fig 2: Close view of hole structure in GEM


Fig 3: The electric field in the GEM Experimental In the Beam test, the GEM Detectors are tested under muon beam of high intensity and the efficiency of the detectors is tested under the conditions of different voltages. The alignment is made proper and the necessary high voltage and gas mixture supplies are provided. The necessary gas mixture is passed and the setup is kept so for around 3 hours for uniform gas distribution through the detector. Voltage of 4300 V is applied to each tracker. The efficiency of timing GEM is calculated for each run as an indication of the performance of the detector. RESULTS AND DISCUSSION

HV(V) I(μA) COUNTS(Hz) CURRENT(nA) 3500 653 4 -3.45 3600 671 4728 -3.51 3700 690 11,111 -3.62 3800 708 34,215 -3.82 3900 727 39,476 -4.21 3950 736 39,575 -4.48 4000 746 40,071 -4.92 4025 751 41,071 -5.13

Table 1: Different counts for different values of the voltages

Graph 1: Counts vs Voltage

VFAT2 is the Integrated Circuit which helps to deal with the signal obtained after collision of

Muon beams. It has two main functions: The first (Trigger) is to provide programmable “fast OR” information based on the region of the sensor hit. The second function (Tracking) is for providing precise spatial hit information for a given triggered event.

Fig4: Block diagram of VFAT Signal flow Conclusion VFAT2 is a “trigger and tracking” front-end ASIC. It has 128 low noise input channels which after discrimination provide binary “hit” information for triggered events. The storage capacity enables trigger latencies of up to 6.4μs, simultaneous storage of data for <128 triggered events. Poisson distributed trigger rates. Time and event tags are added to the triggered data which are then read from the chip in the form of digitized data packets at 40 Mbps.VFAT2 has successfully integrated complex analog and digital functions into a single ASIC without compromising noise performance. Acknowledgement I would like to express my gratitude to Dr. Archana Sharma, for guiding throughout the period of my Internship. I would also like to thank my Institute (NIT Durgapur) professors Dr. N. K. Roy Sir and Dr. P. Kumbhakar Sir for giving me such a great opportunity to pursue my Internship at CERN. Special thanks to Stefano Colfranceschi and Eraldo Olivieri for helping me throughout my project.

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THRESHOLDING USING QUANTUM-DOT CELLULAR AUTOMATA

Anshu S Anand Final year M. Tech. student, Department of Computer Science and Technology


7th International Conference on Innovations in Information Technology Abu Dhabi, UAE, April 27-27, 2011

Abstract Quantum-dot Cellular Automata(QCA), a promising alternative to CMOS technology, can provide a powerful and efficient computing platform for image processing which has heavy computational requirements. Image thresholding is one such image processing technique that plays a significant role in applications of image segmentation for its intuitive properties and simplicity. This work proposes an efficient architecture to carry out thresholding in image processing. It is developed around QCA technology and provides significant improvement over the existing approach. . Introduction VLSI parallel architectures have been widely used to implement video processing techniques which require intensive computations. However the physical limitations of the CMOS technology indicate the difficulty in reducing the device size, power consumption and increase in the operating speed in future designs. VLSI design targets highly regular architecture by keeping the interconnections short and local. These facts lead to the search for alternative technologies for video processors. QCA is one such nanotechnology that can overcome the design limitations of VLSI technology. The above scenario motivates us to investigate a new architecture around QCA which can perform thresholding efficiently. QCA can serve the necessity to implement an efficient digital signal multiprocessor. The adiabatic pipelining scheme in QCA provides an effective solution in obtaining parallelism. Several methods exist for the computation of the threshold. However, due to its

complexity, these methods cannot be implemented with QCA at this stage. Once the threshold value is determined, the proposed QCA design is capable of efficiently applying the thresholding technique to the intensity image. So this work deals only with the thresholding technique, but not the determination of threshold value. Theory / Model The thresholding operation involves identification of a set of thresholds, which are then used to partition the image into mutually exclusive and meaningful regions, in the context of image processing. We present two different ways of implementing thresholding with QCA. While the first method employs an existing serial comparator and is a sequential circuit, the second is a combinationial circuit that exploits pipelining to save clock cycles.

a) Scheme I- Serial Comparator We consider an existing serial comparator to realize the 8-bit comparison. In order to serially compare two n-bit numbers, the comparator performs n bitwise comparisons and memorizes the relation between them throughout the comparison. As in image processing the same comparison operation is to be performed on a large number of pixels, this scheme (serial module) results in a large number of computations, resulting in delayed output. So, even a marginal reduction in the number of clock cycles per operation can result in huge savings in terms of delayed output. The proposed method, in this regard, introduces a simple but quite effective change in the strategy that results in a very significant reduction in the number of clock cycles. While the existing approach suggests bitwise comparison of numbers starting from the LSB that results in fixed number of clock

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National Institute of Technology Durgapur, INDIA Students’ International Research Projects Technical Report; Volume 3, 2011 cycles (n+3), this method reverses the sequence and starts the comparison from MSB instead of from LSB. Because of this, the result of the comparison may be obtained in the first comparison itself (in the best case) and in the last comparison in worst case, if the latency is not taken into account. As soon as the output is obtained, the reset signal is made low to reset the circuit.

b) Scheme II- Parallel Comparator This is based on the combinational circuit and as QCA circuits are inherently pipelined, multiple bits can be processed at the same time. This is possible largely due to the adiabatic clocking mechanism. As per this scheme, the first result (of 8-bit comparison) is obtained after 8 clock cycles. But once the pipeline is filled up, for every additional cycle, one result emerges from the output. The working of this approach was demonstrated using an example of a 2-bit comparator. The comparator was designed and simulated using QCAdesigner. Although this involves disadvantage in terms of greater floor space and number of clock zones, this is largely compensated by the improvement achieved because of the inherent pipelining. It is to be noted that the scheme will not work if the bits are applied in the reverse manner (starting from MSB). Results and Discussion Considering the number of clock cycles as the parameter, we calculate the number of clock cycles required for computation for the different benchmark images, for the three approaches- the existing approach, the serial comparator and the parallel comparator. The number of clock cycles for the proposed approaches were calculated with the help of matlab code. While the existing approach takes 11(8 + 3) cycles for each 8-bit comparison, the proposed scheme II takes one clock cycle for each 8-bit comparison, once the pipeline is full i.e after 7 cycles. The results of the experiment have been summarized in Fig.1. Although the proposed scheme II using combinational circuit is successful in reducing the number of clock cycles consumed, it involves a tradeoff with the number of required logic elements and clocking zones. Whereas the

proposed serial approach consumes larger number of clock cycles while keeping the number of logic elements and clock zones low and hence requires lesser area.

Fig1: Comparison result of the three approaches Conclusion Two new approaches for implementing thresholding are introduced in this paper. Experimental results illustrate the effectiveness of the methods. With the advances being made both in QCA, and the ever increasing computational requirements of image processing, this work can lead more research work in this direction. In future, architecture for the design of a digital signal processor and parallel memory around QCA, is to be explored. Acknowledgement Firstly, I would like to thank NIT Durgapur and authorities for providing the right environment and infrastructure that has helped me in carrying out this work and for funding my visit to Abu Dhabi for presenting this paper. I am very much grateful to my supervisor and guide, Mr. Bibhash Sen for his support and guidance all through my project work. I would also like to thank the entire faculty members of Computer Science and Engineering department for their valuable support. Last but not the least, I express my deepest sense of gratitude to Dr Anjil Kumar Srivastava for guiding me throughout my M. Tech course and for his invaluable suggestions and guidance.

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OPTIMAL DESIGN OF A POWER ELECTRONIC SYSTEM FOR EFFICIENT AND RELIABLE POWER FLOW IN DISTRIBUTED WIND

ENERGY BASED POWER SYSTEMS

Rourav Basak Final year B. Tech. student, Department of Electrical Engineering


International Conference on Energy and Electrical Systems (ICEES 2011) In conjunction with the 3rd ICSTE 2011 by ASME

Kuala Lumpur, Malaysia. August 12-13, 2011

Abstract Wind energy turbines, when connected to the grids are unreliable sources of power, which cause many stability problems to the entire system. When additional power is required, an energy flow is needed between a battery stack and the consumer load. In this paper, an attempt to design a distributed PES [Power Electronics Sub-System] comprising of a dc-dc boost converter, wind-turbine-set and the battery has been made. The purpose of the paper is to describe a power management control system for a distributed PES, and outline how to calculate an optimal number of power converter modules [dc-dc boost converter], so that maximum energy conversion efficiency is achieved. To increase the response time of the battery stack we use a gate controlled diode. Introduction Power system operating practices are built around meeting the variable load with generators that can change their output level. Wind adds more variability to the system, because no trustworthy technology to predict wind energy is still available. During sudden increase in load demand, or in the event of sudden dip in wind energy, there may not sufficient power available in the tie-lines to the consumer ends, and thus causing instability in the entire power system. A power management control system for a distributed PES, comprising multiple modules of dc-dc boost converters for a wind-turbine system is outlined to meet the existing problems Proposed Model and working Figure 1 shows the topology of the distributed

Power Electronic Subsystem (PES), which interfaces to the wind-turbine generator-set and the battery-capacitor arrangement. It consists of a bidirectional dc-dc boost converter module (for illustrative purpose). Should the number of these modules N shall depend on the maximum load demand and the rated capacity of the individual converter modules. The switches being used in this scheme are gate controlled diode, MOSFETs-which are fast switching devices. The new proposed scheme takes care of the transient phase, when there is a sudden increase in load demand or dip in generator production. A battery bank is associated with the capacitor in parallel. They are charged when the wind turbine supplies power to the grid. The batteries get charged from the grid. When the wind speed falls the transient phase is covered by the battery and the control system is there for required switching. This avoids any instability in the grid or any delay in the system. The delay will incorporate more instability which is also avoided here. Thus system stability is reached with the help of this Power Electronic System. Transfer of supply-to-the-rotor from the Battery bank to the Capacitor is done in gradual way of switching from the control system so that instability does not occur in the system. The gate controlled diode, which is connected in reverse bias and the breakdown, is controlled by a gating signal [11]. The gating signal comes from a NOT gate. Output of the NOT gate is 1 when the Input that is the voltage at the arm of the switch is zero, i.e. grounded. So the output voltage at the DC link is maintained by this new power electronics device associated with the scheme. Thus the system provides

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protection against transient instability. As the load demand increases, the number of boost converter needs to be increased from 1 to N, as per the demand. In most practical cases, an optimal criterion deserves to be determined, to find the number of such modules that need to be activated for maximum PES energy-conversion efficiency that, in return, leads to enhanced battery stack utilization. Overall, the distributed-PES-based power-management-control scheme leads to enhanced source utilization due to better PES efficiency profile and reduces transient instability, weight, and cost for battery buffering by sufficiently reducing the requirement for a dedicated full-power-rating converter for the battery

Figure 1: Schematic Circuit Diagram of the PES

Optimal Criterion Determination In case of practical systems, an optimal number of boost converters are required intermediately unless the wind generator can supply the required load. The calculation most efficient number of boost converters required for maximum efficiency of the PES, is referred to as the Optimal Criterion Determination. Losses take place in the boost converters due to switching losses,

impedance of the inductor, capacitor, stray capacitances, and losses due to lumped parameters. For a converter operating at a particular switching frequency, the total loss is a function of I for a given Vin and Vbus.

For multiple components:

To maximize the efficiency of the multi-converter system with m = N-1 number of active modules (it is noted that the Nth converter is always connected to the battery), the objective function Jm for a given Vstack is defined as:

, where j=1, …, m (=N-1) and IT=[I1,I2,…,Im]T with the following two constraint:

Using Matlab, we can find the minimum of the objective function, hence the maximum efficiency. Optimization can be achieved by simply mapping the losses. Conclusion This work primarily proposes a method to increase the reliability of a power grid connected to wind turbine. The PES control scheme will ensure that the consumers continue to receive power without much dip or distortion during transients or during sudden increase in load, or un-forecasted decrease in wind energy. Overall, the distributed-PES-based power-management-control scheme leads to enhanced source utilization due to better PES efficiency profile. Acknowledgement I would like to thank my co-author Sayonsom Chanda, whose inputs have been instrumental for the paper. My special thanks to Dr. S. Banerjee who helped me develop my concepts important to this paper. I would like to thank all my HOD Dr. N.K. Roy and all teachers for the support. I express my special gratitude to the Director, NIT Durgapur and Financial Committee for encouraging me to


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attend the conference. QOS ADAPTATION IN DISTRIBUTED MULTIMEDIA BASED

COLLABORATIVE ENVIRONMENT

Shrutilipi Bhattacharjee Final year M. Tech. student, Department of Information Technology


4th International Conference on Modeling, Simulation and Applied Optimization – ICMSAO 2011, Kuala Lumpur, Malaysia, April 19-21, 2011

Problem Description Abstract

Powerful end systems of distributed multimedia based application in high speed collaborative environment interact for different types of applications which need adaptation of best Quality of Service (QoS) configuration. For this issue we propose a QoS management framework for multimedia application mainly for the domain teleteaching which supports the dynamic choice of configuration as per user requirements and changes of underlying network topology. We specially focus on the bandwidth reallocation scheme for every multimedia service for a particular synchronous session. We concentrated on QoS negotiation and adaptation mechanism using Diffserv and the simulation result using Qualnet Network Simulator.

In collaborative distributed environment, suppose there is n number of nodes in the network at time ti. The nodes are represented as Ni where i 1 to n. At a particular time, any one of the nodes acts as a sender and rest of the nodes are receiver. For time ti, all the nodes are associated with a number of multimedia services. Suppose the services are represented as Sj ; j1 to m i.e. m number of multimedia services are there in the network for a particular application. Each service is associated with a QoS level required by a particular node. Suppose service Si has QoS level QSi [xi-q, xi+p] bits/second where xi=average bit rate of service Si, xi+p = maximum QoS/upper threshold of service.

If B is bandwidth of a particular link at time ti for destination node Ni then, B = . Suppose at time ti+1 at a particular node a user requires QoS of Si = xi+a where value of a is such that xi < a < xi+p a

∑ ix

⇒ ∈ [xi, xi+p]. So the bandwidth requirement for that service Si= xi+a. Then ∀ Sj (j∈1 to m, j≠ i), P(Sj,B-(xi+a))=true where P(x,y)=cumulative bandwidth required for all x is y i.e. upgradation of QoS of Si will result in degradation of QoS of selective Sj ’s for a particular node i.e. upgradation of QoS of Si≈degradation of QoS of all Sj(i j). ≠

Introduction In collaborative distributed environment a number of multimedia applications like video-on-demand, videoconferencing, video-telephony, electronic news, teleteaching, e-commerce etc used to run concurrently. Quality of Service (QoS) management is important here because they compete for a limited number of resources, mainly bandwidth. One of the most popular applications in this environment is teleteaching where teacher terminal and all the student terminals used to interact with each other in location independent manner. In this paper, we have proposed an algorithm which is capable to receive user requirement dynamically. Here we also have considered students behavioral and corresponding technical requirements from psychological perspective. To simulate our proposed algorithm we have used a network simulator called Qualnet in which DiffServ is implemented in selected nodes. Result proves that adaptation may vary depending on requirement of the concerned users for that node.

Here we have considered students and teachers behavioural requirements from psychological perspective. Some of those requirements are as follows,

Teachers Behavioural Requirement 1) Teacher’s Behavioral Requirement 1: To concentrate on a particular student’s performance in the class, teacher wants to see his/her classwork i.e. students workspace x: Teacher wants to see/concentrate on student’s classwork, y: Teacher pays more concentration


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on video of student ith workspace and P(x,y)=true. 2) Teacher’s Behavioral Requirement 2: If teacher want to ask a question to a student during the class hour, teacher want to interact with him/her during question-answer session [with face-to-face eye contact]. x:Teacher want to ask question or interact with studenti, y: Teacher gives whole attention to the incoming audio/video of the ith student and P(x,y)=true. Student Behavioural Requirement 1) Student’s Behavioural Requirement 1: When teacher is giving any speech, students wants to concentrate on teachers face[video] and speech[audio] more than his/her workspace. x: student want to concentrate more on teacher face than his workspace, y: incoming audio and video of teacher should be concentrated here and P(x,y): true. 2) Student’s Behavioural Requirement 2: If teacher is doing any boardwork on his/her workspace, students want to concentrate on boardwork [& speech if there] x: as teacher is doing boardwork all students require to view it properly, y: incoming video of teacher’s workspace should be concentrated here and P(x,y)=true. Regarding all the behavioural and corresponding technical requirements, there are 9 different services in teleteaching application (from student perspective) that we will be dealing with. They are like, S1: incoming audio of the teacher. S2: incoming video of teacher face. S3: incoming video of teacher workspace. S4: outgoing control messages for menu. S5: incoming/outgoing text messages. S6: outgoing control messages for zooming. S7: outgoing video of studenti. S8: outgoing audio of studenti. S9: outgoing video of ith student’s workspace. Now say average bandwidth requirement of service Si=xi and bandwidth allocated for a particular session to a particular link=B bit. If all the services are at their average bit rate then, x1(S1)+ x2(S2)+…+ x9(S9)=B where x9(S9)=present bandwidth requirement of Si is xi. So to zoom into a particular service (to

allocate more bandwidth), bandwidth adaptation is necessary.

Implementation Depending upon our proposed algorithms, we have created a scenario in a network simulator called Qualnet with 11 nodes. 4 different MCBR services are multicast by sender node 1 to all other nodes. Now in node number 3 and 4 we have implemented DiffServ. In node 3, user requirement is to upgrade 1st MCBR’s quality (from 9 to 14) resulting degradation of 2nd MCBR (from 9 to 4) and in node 4, user requirement is to upgrade 3rd MCBR’s quality(from 9 to 15) resulting degrading 1st MCBR quality(from 9 to 3) where total number of packet received should be fixed. The result proves that the adaptation is not static for all the nodes, it can be varied depending on requirement of the concerned users for a particular node. Hence this proves our proposed algorithm.

Figure 2: Environment created in Qualnet simulator

Figure 3: Result of the environment described and

shown above Conclusions In this research work, we have considered students behavioral requirement from psychological perspective. Even if by adjusting the bandwidth of a link best QoS configuration cannot be delivered to the users, then we may think of searching for alternate path to serve our purpose i.e. renegotiation process. Acknowledgement This work is supported by Department of Information Technology of National Institute of Technology Durgapur, West Bengal, India.


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STRUCTURAL BIOINFORMATICS STUDY OF 5-ENOLPYRUVYLSHIKIMATE - 3-PHOSPHATE (EPSP) SYNTHASE FROM

BORDETELLA PERTUSSIS

Sagarika Bhattacharya Final year MBA student, Department of Management Studies


45th International Conference on Global Challenges – the role of chemistry in giving their solutions, Bangkok, Thailand

June 11-15, 2011

Abstract Bordetella pertussis causes pertussis or the whooping cough disease which claims an alarming number of lives each year owing possibly to the emergence of resistance to the antimicrobials of choice for the treatment of Bordetella pertussis infections. All the shikimate pathway enzymes form attractive targets for herbicides and antimicrobial agent development because the pathway is essential in algae, higher plants, bacteria, and fungi, but absent from mammals. In the present work molecular model of the sixth enzyme of the pathway, 5-enolpyruvylshikimate-3-phosphate (EPSP) synthase in Bordetella pertussis has been generated. The architecture of the active site has been described based on the prediction of active site residues. This should provide a structural framework to guide enzymological studies and design of specific inhibitors that could serve as new and effective antibiotics against the Bordetella pertussis bacterium. Introduction

Infections of the respiratory tract are one of the biggest killer diseases of the world. Pertussis is a vaccine-preventable disease but communicable disease. Bordetella pertussis, which causes pertussis is a Gram-negative bacteria of the genus Bordetella. In children the disease brings about paroxysmal spasms of severe coughing, whooping, and posttussive vomiting. The cough precedes a crowing inspiratory sound which is characteristic of pertussis. Adults show milder symptoms, like prolonged coughing without the “whoop.”A coughing spell may cause cyanosis, apnoea and seizures. Other major complications are hypoxia, pneumonia, encephalopathy, and malnutrition. This disease results in high

morbidity and mortality in many countries every year.

The first clear description of pertussis (whooping cough) was made by Baillou in 1640. However, even in countries with high vaccination rates, there have been recent reports of increases in cases in The Netherlands and in the United States. Although erythromycin or macrolides remain the antimicrobials of choice for the treatment of Bordetella pertussis infections, there have been reports of the emergence of resistance to these agents in clinical isolates from the United States

The shikimate pathway links the metabolism of carbohydrates to the biosynthesis of ring-containing compounds. The shikimate pathway is essential in algae, higher plants, bacteria, and fungi, but absent from mammals that depend on these compounds for their diet. In the shikimate-pathway enzymes as potential targets for non-toxic herbicides and anti-microbial compounds . The precise enzyme target for glyphosate is 5-enolpyruvylshikimate- 3-phosphate synthase (EPSP synthase), the sixth enzyme of the pathway, encoded by aroA gene, that catalyzes the transfer of the enolpyruvyl moiety from phosphoenolpyruvate (PEP) and inorganic phosphate.

Recent studies confirm that the pathway enzymes may offer scope for developing broad-spectrum antibiotics. It is possible that a single compound that inhibits the shikimate pathway could be used to treat patients with multiple infections. Here the three dimensional structure prediction for EPSP synthase is described.


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Experimental Databases The amino acid sequences of the experimentally characterized, 5-enol-pyruvyl-shikimate-3-phosphate (EPSP) synthase enzyme were obtained from the protein sequence database at NCBI. The 3-D structures of proteins were obtained from the protein data bank. Model generation The homology model of Bordetella pertussis EPSPS was constructed using the MODELLER version 9v1 (default parameters), based upon the sequence/template alignment. It generates a refined 3D homology model of a protein sequence automatically and rapidly, based on a given sequence alignment to a known 3D protein structure. which is the approach most likely to give accurate results There are two main approaches to homology modeling: (1) fragment-based comparative modeling and (2) restrained-based modeling For modeling of the Bordetella pertussis (BpEPSPS) we used the second approach. The geometry of loop regions was corrected using MODELLER/Refine Loop command. Model validation The overall stereochemical quality of the final model for the complex BpEPSPS: Glyphosate: S3P was assessed by the program COOT. The root mean square deviation (RMSD) between the main chain atoms of the model and template was calculated for the reliability of the model. Results and Discussion Quality of the model The Ramachandran plot for the EcEPSPS (1G6S) structure was generated in order to compare the overall stereochemical quality of BpEPSPS model against EPSP structures solved by biocrystallography. Analysis of the Ramachandran plot of the BpEPSPS model shows that over 90% of the residues lie in the most favorable regions and about 4% in the allowed region. Overall description EPSP synthase is an α/β protein. Each domain contains β sheets and six parallel α helices aligned in a way that their macrodipoles create

a significant electropositive attraction for the anionic ligands at the interface between the two domains. The amino and carboxyl termini of the protein lie in the same domain and domains are connected via two crossover chain segments. The glyphosate and S3P molecules are bound in the interdomain cleft. Active site architecture: 3-Phosphoshikimate and glyphosate binding The glyphosate and the S3P bind in the cleft in the hinge region and are lined with several conserved and non conserved amino acid residues EPSPS structures solved till date like Streptococcus pneumoniae EPSPS (SpEPSPS) and the CP4 EPSPS exist in an open, unliganded state and a closed, S3P liganded state, suggesting an induced-fit mechanism with binding of S3P as a prerequisite for the enzyme’s interaction with PEP. The same may be proposed to hold true for BpEPSPS. In the enzyme’s binary complex with S3P, this loop becomes structured and interacts with the N-terminal domain to constitute the active site Direct hydrogen bonds and salt bridges are observed in the hinge region and the the cleft between domains. The majority of these interdomain interactions could be formed by the simple domain approach without significant motion of the participating residues as observed in SpEPSPS. Conclusion Shikimate pathway enzymes hold great promise for the development of drugs against bacterial, fungal and apicomplexan parasitic diseases. Each of the enzymatic steps is important and the availability of structures for the pathway enzymes will help development of useful drugs. It is hoped that the molecular structure of BpEPSPS predicted in this work will provide insights on designing antimicrobial agents against the whooping cough disease.


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A NOVEL APPROACH OF POWER FLOW ANALYSIS BY POWER

PERTURBATION METHOD

Sankari Prasad Bose Final year M. Tech student, Department of Electrical Engineering


IEEE Control and System Graduate Research Colloquium, Shah Alam, Malaysia

June 27-28, 2011

Abstract This paper proposes an efficient and reliable method based on perturbation method that has been developed to provide a smarter solution with minimum number of iterations, high accuracy and less time. The developed method is tested on different standard IEEE 5 bus, 14 bus & 30 bus systems to show its effectiveness & efficiency.

Introduction The present electrical power system is continuously expanding in size and growing in complexity. System stability and reliability are of utmost concern. A power system engineer is always concerned with adopting newer and better mathematical model for solving system problem more efficiently and effectively. The load flow study is an important tool involving numerical analysis applied to a power system. Load flow calculations still are the basis for planning and operation of power systems. It analyzes the power systems in normal steady-state operation. The importance of load-flow studies is in planning the future expansion of power systems as well as in determining the best operation of existing systems. The principal information obtained from the power flow study is the magnitude and phase angle of the voltage at each bus and the real and reactive power flowing in each line. There are several iterative techniques are available for solving these problems on digital computers .Some modifications on the existing methods are shown in. In this paper a novel and efficient method based on perturbation method has been proposed which keeps the conventional techniques in load flow analysis such as the Newton-Raphson Load Flow (NRLF) method, P-Q decoupled load flow method, etc., intact,

hence it inherits entire advantages, in both speed and convergence, of conventional techniques and therefore it can be used in real time applications. This method is compared with Fast Decoupled method. Perturbation Method A useful way of studying theories that cannot be solved exactly is by computing power series expansions in a small parameter. Quantum electrodynamics, for instance, has a small parameter, called the fine structure constant, which is given by

& T (α) denotes some physical quantity of interest, one computes

The first few terms can give a very good approximation. This approach is called perturbation technique. By consideration as α to be very small and non zero if Power Perturbation method is applied to load flow problem can be formulated. The required equations as given below .

− Where Y indicates the admittance matrix and S is the complex power. Vsp is the specified voltage magnitude. For the calculation of active power P and reactive power Q the following formulas may be applied.


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Performance Analysis Load Flow based on the Power Perturbation Method displays not only rigidity but also convergence for standard as well as for strained test systems. Network size is one of the most important factors on which the functioning of this method depends. This method gives consistent results and was tested on IEEE 5-bus, IEEE 14-bus and IEEE 30 bus system. The proposed approach has been implemented using MATLAB (Version: 7.8.0.347 Build: R2009a) on Microsoft Windows environment (Version 5.1: Build 2600: on Intel Core i7 CPU 3.00 GHz, 2GB RAM, 250 GB Hard Disk machine). Results and Discussion The time comparison between methods is not straightforward owing to the different approaches, but all the methods reach a negligible power mismatch at the end of a solution. Table 1 shows the comparison of iterations required to converge by the proposed method is less than the conventional Fast-Decoupled method.

TABLE I. COMPARISON OF NUMBER OF ITERATIONS FOR FDLF & PP METHOD

IEEE System FDLF PP Method 5 Bus 3 1 14 Bus 3 1 30 Bus 5 2

Fig. 1 shows the performance of fast decoupled and proposed method in graphical form. It can be observed that the proposed technique is very robust and proficient in terms of convergence time as well as number of iterations.

Figure 1. Comparison of No. of iterations for different IEEE bus systems for Fast Decoupled and proposed Power Perturbation methods.

Table 2 shows the overall performance of the two methods in terms of accuracy. The accuracy varied from 10-1 to 10-3 and is tested on IEEE 5-Bus test systems.

TABLE II. TEST RESULTS FOR IEEE 5 BUS SYSTEM

Accuracy Factor (ζ)

F-D no. of iterations

P-P no. of iterations

10-1 3 1 10-2 6 2 10-3 9 2

Conclusion A robust and efficient method based on Power perturbation method has been developed for solving the load flow problem. The procedure is relatively simple, fast, and reliable and can easily be adopted for, where other methods fail to give better solutions. The performance of the proposed Power Perturbation method has been evaluated by testing it on IEEE 5-bus, 14-bus and 30-bus test systems. Hence proposed method can be implemented easily and is more suitable for practical applications. Further research work can be done on Power-Perturbation method for more complex bus system as well as ill-conditioned systems to verify its ability of convergence, robustness and the pace at which it is providing the solution.


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CHEMICAL SYNTHESIS AND INVESTIGATION ON PHOTOLUMINESCENCE PROPERTIES OF TRIPHENYLPHOSPHINE

FUNCTIONALIZED SINGLE WALL CARBON NANOTUBES

Rima Paul Institute Research Scholar, Department of Physics National Institute of Technology Durgapur, INDIA

Xth International Conference on Nanostructured Materials- Nano 2010, Rome, Italy,

September 13-17, 2010 Abstract Using a very simple wet chemical process, purified single wall carbon nanotubes (SWCNTs) are treated with triphenylphosphine (Ph3P) at room temperature. The hybrid structure shows remarkable green emission with peak around 500 nm, when excited by UV radiation of wavelength 260-300 nm. The photoluminescence (PL) emission of the hybrid structure is attributed to the charge transfer between the electron-donating phosphorous atom and carbon nanotubes. This nanohybrid may find wide application in sensor based devices. Introduction Modification of SWCNT surfaces with functional groups can increase their solubility or stability in a medium making them efficient for several practical applications. In the present study we report a simple chemical method of surface modification of SWCNTs by attaching Ph3P nanocrystals on its surfaces. The charge transfer between the nanotubes and Ph3P significantly alter the electronic properties of the nanotubes. The luminescence characteristics of such functionalized nanotubes under UV excitation are reported. Experimental SWCNTs (1-2 nm outer diameter, length: 1-3 µm and purity >95%) have been procured and further purified. To 100 ml of tetrahydrofuran (THF), 5000 mg of Ph3P has been added to make 0.2 M Ph3P solution. The solution is then stirred for 10 min using magnetic stirrer. 5 mg of SWCNT has been poured to the solution and stirred for 48 h followed by sonication for 5 min. Filtration of this Ph3P treated SWCNT has been done using Whatman filter paper and then washed thoroughly with deionised water

followed by drying at room temperature. Four other samples, 0.10 mg/ml, 0.50 mg/ml, 1.50 mg/ml and 2.50 mg/ml have also been prepared following the same procedure. Here we will designate the samples 0.05 mg/ml, 0.10 mg/ml, 0.50 mg/ml, 1.50 mg/ml and 2.50 mg/ml as A, B, C, D and E respectively. Characterization of the as-prepared sample have been done by SEM/EDAX (HITACHI S-3000N) and XRD (Philips PANalytical X-Pert Pro diffractometer with CuKα radiation, λ = 0.154056 nm). Compositional analysis of the sample is done by FTIR (Nicolet iS10) spectroscopy. FTIR analysis confirmed the presence of phosphine group with SWCNTs. The microstructure of the surfaces of SWCNT bundles attached with phosphine has been confirmed by HRTEM (JEOL JEM 2100) micrograph using an operating voltage of 200 kV. Raman spectroscopy has been performed using TRIAX 550 JY Horiba USA. Argon ion laser of wavelength 488 nm has been used as an excitation source for Raman spectroscopy. To study the optical property of SWCNT/Ph3P nanostructure, the dried sample is dispersed in dimethyl sulfoxide (DMSO) and its optical absorbance characteristics studied using UV-Vis (HITACHI U-3010) spectrophotometer. PL spectrum of the sample has been studied using FL spectrofluorimeter (HITACHI, F-2500). Results and Discussion Fig 1 shows the HRTEM micrograph of SWCNT/Ph3P (sample B) material. From the micrograph it is clearly observed that Ph3P nanoparticles (NPs) are uniformly decorated on to the walls of the SWCNT bundles and artistically at the tip of the SWCNT bundle.


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Fig 1: HRTEM micrograph of SWCNT/Ph3P (sample B) material; insets show the SAED pattern and particle size distribution of Ph3P around SWCNT bundle The insets show the SAED pattern and particle size distribution of Ph3P NPs that are attached onto the walls of SWCNT bundles. The SAED pattern clearly reveals the crystalline nature of the Ph3P NPs. By using curve fitting technique, the average size of Ph3P NPs is found to be 27.5 nm.

Fig 2: EDAX spectrum of SWCNT/ Ph3P material

The presence of phosphine (P) is confirmed from EDAX spectrum as shown in Fig 2. C indicates the presence of SWCNTs, Si and O are due to glass substrate. From 220-240 nm excitation wavelengths, sample B showed luminescence with peak position at 350 nm. When excited by 250 nm radiation, a hump with peak around 500 nm emerges as shown in Fig 3. Further increasing the excitation wavelength makes the hump prominent and the primary emission part. This phenomenon is not seen in the case of samples with different concentrations of SWCNTs with Ph3P.

300 350 400 450 500 550 600 650

SWCNT/Ph3P

Inte

nsity

(a.u

.)

Wavelength (nm)

220 nm 230 nm 240 nm 250 nm 260 nm

Fig 3: PL spectrum of SWCNT/Ph3P (sample B) at excitation wavelength from 220-260 nm Hence this concentration [sample B] is the optimized concentration for which we obtained remarkable green luminescence. The luminescence intensity gradually increased with the increase in excitation wavelength from 260-300 nm. Above 300 nm excitation wavelength, no considerable luminescence was observed. The PL emission of the hybrid structure is attributed to the charge transfer between the electron-donating phosphorous atom and carbon nanotubes. The number of electrons taking part in the transition process get increased with increasing excitation wavelength and hence increase in PL intensity. But on further exciting the hybrid structure with increased wavelengths, electrons get trapped by SWCNTs and hence no pronounced emission has been observed. Conclusion We reported a simple chemical process of functionalization of SWCNTs by attaching Ph3P nanocrystals of average size 27.5 nm on their surfaces. We found an optimized proportion of the constituents in the hybrid structure for which the composite material transformed into an attractive photoluminescent material which showed brilliant green emission in the visible range with the peak emission around 500 nm. Acknowledgement We are grateful to NIT Durgapur for financial support and thankful to IIT Kharagpur, for making available the HRTEM and Raman Spectroscopy facilities.