Ch09 Service Opera Ti Ions

8/8/2019 Ch09 Service Opera Ti Ions

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1 2002 South-Western/Thomson Learning2002 South-Western/Thomson Learning TMTM

Slides preparedSlides prepared

by John Loucksby John Loucks


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Chapter 9Chapter 9Chapter 9Chapter 9

Service OperationsService Operations

Planning and SchedulingPlanning and Scheduling


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OverviewOverviewOverviewOverview

IntroductionIntroduction

Scheduling QuasiScheduling Quasi--Manufacturing Service OperationsManufacturing Service Operations

Scheduling CustomerScheduling Customer--asas--Participant ServiceParticipant Service

OperationsOperations Scheduling CustomerScheduling Customer--asas--Product Service OperationsProduct Service Operations

WrapWrap--Up: What WorldUp: What World--Class Companies DoClass Companies Do


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IntroductionIntroductionIntroductionIntroduction

ServicesServices are operations with:are operations with:

Intangible outputs that ordinarily cannot beIntangible outputs that ordinarily cannot be

inventoriedinventoried

Close customer contactClose customer contact Short lead timesShort lead times

High labor costs relative to capital costsHigh labor costs relative to capital costs

Subjectively determined qualitySubjectively determined quality


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Facts about service businesses:Facts about service businesses:

Enormous diversityEnormous diversity

Service businesses can be any sizeService businesses can be any size

Twice as many nonTwice as many non--retail service businesses asretail service businesses asretailretail

Technical training important due to significantTechnical training important due to significant

dependence on computers, automation anddependence on computers, automation and

technologytechnology


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OtherFacts about service businesses:OtherFacts about service businesses:

Service workers well paid relative toService workers well paid relative to

manufacturingmanufacturing

Need better planning, controlling, andNeed better planning, controlling, andmanagement to stay competitivemanagement to stay competitive


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Some of the Largest Service BusinessesSome of the Largest Service BusinessesSome of the Largest Service BusinessesSome of the Largest Service Businesses

Rank in the top 20 US Corporations:Rank in the top 20 US Corporations:

AT&TAT&T

WalWal--MartMart

CitigroupCitigroup State FarmState Farm

SBC CommunicationsSBC Communications

Sear,R

oebuck & CompanySear,R

oebuck & Company


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Spectrum of Service IndustriesSpectrum of Service IndustriesSpectrum of Service IndustriesSpectrum of Service Industries

TransportationTransportation BankingBanking

RetailingRetailing

Health CareHealth Care

EntertainmentEntertainment

InsuranceInsurance Real EstateReal Estate

CommunicationsCommunications

UtilitiesUtilities

and more and more


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No Clear Line BetweenNo Clear Line Between

Manufacturing and Service FirmsManufacturing and Service Firms

No Clear Line BetweenNo Clear Line Between

Manufacturing and Service FirmsManufacturing and Service Firms

EveryEvery business, whether manufacturing or service,business, whether manufacturing or service,

has a mix of customer service aspects and productionhas a mix of customer service aspects and production

aspects in its operationsaspects in its operations

Manufacturing has much to learn from services thatManufacturing has much to learn from services thatexcelexcel

Services have much to learn from manufacturers thatServices have much to learn from manufacturers that

excelexcel


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Manufacturing and Service JobsManufacturing and Service JobsManufacturing and Service JobsManufacturing and Service Jobs

Percentage of US JobsPercentage of US Jobs

19881988 19981998 2008*2008*

Manufacturing JobsManufacturing Jobs 16.1%16.1% 13.4%13.4% 11.6%11.6%

Service JobsService Jobs 66.266.2 70.870.8 73.973.9

* Projected* Projected


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Operations StrategiesOperations StrategiesOperations StrategiesOperations Strategies

Positioning strategiesPositioning strategies contain two elements:contain two elements:

Type of service designType of service design

Standard or customStandard or custom

Amount of customer contactAmount of customer contact Mix of physical goods and intangible servicesMix of physical goods and intangible services

Type of production processType of production process

QuasiQuasi--manufacturingmanufacturing

CustomerCustomer--asas--participantparticipant

CustomerCustomer--asas--productproduct


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Types of Service OperationsTypes of Service OperationsTypes of Service OperationsTypes of Service Operations

QuasiQuasi--manufacturingmanufacturing

Production occurs much as manufacturingProduction occurs much as manufacturing

Physical goods dominant over intangible servicesPhysical goods dominant over intangible services

CustomerCustomer--asas--participantparticipant High degree of customer involvementHigh degree of customer involvement

Physical goods may or may not be significantPhysical goods may or may not be significant

Service either standard or customService either standard or custom

CustomerCustomer--asas--productproduct

Service performed on customer... usually customService performed on customer... usually custom


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Scheduling Challenges in ServicesScheduling Challenges in ServicesScheduling Challenges in ServicesScheduling Challenges in Services

Planning and controlling dayPlanning and controlling day--toto--day activitiesday activities

difficult due to:difficult due to:

Services produced and delivered by peopleServices produced and delivered by people

Pattern of demand for services is nonPattern of demand for services is non--uniformuniform


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NonNon--Uniform DemandUniform DemandNonNon--Uniform DemandUniform Demand

Cannot inventory services in advance of highCannot inventory services in advance of high--demanddemand

periods, so businesses use following tactics:periods, so businesses use following tactics:

Preemptive actions to make demand more uniformPreemptive actions to make demand more uniform

OffOff--peak incentives/discounts (telephone)peak incentives/discounts (telephone) Appointment schedules (dentist)Appointment schedules (dentist)

Fixed schedules (airline)Fixed schedules (airline)

Make operations more flexible so it is easier toMake operations more flexible so it is easier to

vary capacityvary capacity PartPart--time personnel (supermarket)time personnel (supermarket) Subcontractors (postal service)Subcontractors (postal service) InIn--house standby resources (fire department)house standby resources (fire department)


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NonNon--Uniform DemandUniform DemandNonNon--Uniform DemandUniform Demand

Additional tactics used by businesses:Additional tactics used by businesses:

Anticipate demand and schedule employees duringAnticipate demand and schedule employees during

each time period to meet demandeach time period to meet demand

Allow waiting lines to formAllow waiting lines to form These two tactics will be covered in greater detailThese two tactics will be covered in greater detail


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Scheduling QuasiScheduling Quasi--Manufacturing ServicesManufacturing ServicesScheduling QuasiScheduling Quasi--Manufacturing ServicesManufacturing Services

ProductProduct--Focused OperationsFocused Operations

Resemble productResemble product--focused production linesfocused production lines

Customer demand is forecast and capacityCustomer demand is forecast and capacity

decisions made just as in manufacturingdecisions made just as in manufacturing High volumes of standardized productsHigh volumes of standardized products

Management focused on controlling productionManagement focused on controlling production

costs, product quality, and delivery of physicalcosts, product quality, and delivery of physical

goodsgoods

Example... McDonalds backExample... McDonalds back--room operationroom operation


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Scheduling QuasiScheduling Quasi--Manufacturing ServicesManufacturing ServicesScheduling QuasiScheduling Quasi--Manufacturing ServicesManufacturing Services

ProcessProcess--Focused OperationsFocused Operations

Managed like job shops in manufacturingManaged like job shops in manufacturing

InputInput--output control important to balance capacityoutput control important to balance capacity

between operationsbetween operations Gantt charts used to coordinate flows betweenGantt charts used to coordinate flows between

departmentsdepartments

Sequence of jobs consider sequencing rules,Sequence of jobs consider sequencing rules,

changeover costs, and flow timeschangeover costs, and flow times


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Work Shift SchedulingWork Shift SchedulingWork Shift SchedulingWork Shift Scheduling

Three difficulties in scheduling services:Three difficulties in scheduling services:

Demand variabilityDemand variability

Service time variabilityService time variability

Availability of personnel when neededAvailability of personnel when needed Managers use two tactics:Managers use two tactics:

Use fullUse full--time employees exclusivelytime employees exclusively

Use some fullUse some full--time employees as base and fill intime employees as base and fill inpeak demand with partpeak demand with part--time employeestime employees


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Example: Scheduling EmployeesExample: Scheduling EmployeesExample: Scheduling EmployeesExample: Scheduling Employees

The owner of a haircutting shop wants to convertThe owner of a haircutting shop wants to convertfrom a dropfrom a drop--in system of customer arrivals to anin system of customer arrivals to anappointment system.appointment system.

Each customer requires an average of 30 minutesEach customer requires an average of 30 minutes

of a stylists time. The stylists are all fullof a stylists time. The stylists are all full--timetimeemployees and can work any 4 consecutive days peremployees and can work any 4 consecutive days perweek from 10 a.m. to 7 p.m. (with an hour off forweek from 10 a.m. to 7 p.m. (with an hour off forlunch), Monday through Saturday.lunch), Monday through Saturday.

On the next slide are: 1) average number of dropOn the next slide are: 1) average number of drop--in customers each day, and 2) estimated number ofin customers each day, and 2) estimated number ofcustomer appointments each day.customer appointments each day.


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Mon.Mon. Tue.Tue. Wed.Wed. Thu.Thu. Fri.Fri. Sat.Sat. TotalTotal

DropDrop--insins 4040 3030 1010 2020 3030 6060 190190

AppointmentsAppointments 3232 3232 3232 3232 3232 3232 192192

a) How many stylists are required to service 32a) How many stylists are required to service 32appointments in a day?appointments in a day?

b) What is the minimum number of stylists required perb) What is the minimum number of stylists required per

week?week?c) Use the work shift heuristic procedure to develop thec) Use the work shift heuristic procedure to develop the

stylists weekly work shift schedules.stylists weekly work shift schedules.


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Number of Stylists Required per DayNumber of Stylists Required per Day

Number of customers per dayNumber of customers per day

Number of work hours Number of customers Number of work hours Number of customers

per day per stylistper day per stylist served per hour per stylistserved per hour per stylist

= 32/((8)(2)) = 2 stylists= 32/((8)(2)) = 2 stylists


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Minimum Number of Stylists Required per Week?Minimum Number of Stylists Required per Week?

Number of Customers per WeekNumber of Customers per Week

Number of Customers per Stylist per WeekNumber of Customers per Stylist per Week

= 192/((8 hr/day)(4 days/week)(2 cust./hr/stylist))= 192/((8 hr/day)(4 days/week)(2 cust./hr/stylist))

= 192/64 = 3 stylists= 192/64 = 3 stylists


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Stylists Weekly Work Shift SchedulesStylists Weekly Work Shift Schedules

StylistStylist Mon.Mon. Tue.Tue. Wed.Wed. Thu.Thu. Fri.Fri. Sat.Sat.

11 22 22 22 22 22 2222 22 22 11 11 11 11

33 11 11 11 11 00 00

Note: Pair of days boxed represent days off.Note: Pair of days boxed represent days off.


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Scheduling CustomerScheduling Customer--asas--Participant ServicesParticipant ServicesScheduling CustomerScheduling Customer--asas--Participant ServicesParticipant Services

Must provide customer ease of use/access features....Must provide customer ease of use/access features....lighting, walkways, etc.lighting, walkways, etc.

Layouts must focus on merchandising and attractiveLayouts must focus on merchandising and attractive

display of productsdisplay of products

Employee performance crucial to customerEmployee performance crucial to customer

satisfactionsatisfaction

Waiting lines used extensively to level demandWaiting lines used extensively to level demand


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Waiting Lines in Service OperationsWaiting Lines in Service OperationsWaiting Lines in Service OperationsWaiting Lines in Service Operations

Waiting lines form because:Waiting lines form because:

Demand patterns are irregular or random.Demand patterns are irregular or random.

Service times vary among customers.Service times vary among customers.

Managers try to strike a balance betweenManagers try to strike a balance betweenefficiently utilizing resources and keepingefficiently utilizing resources and keeping

customer satisfaction high.customer satisfaction high.


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Waiting Line ExamplesWaiting Line ExamplesWaiting Line ExamplesWaiting Line Examples

Computer printing jobs waiting for printingComputer printing jobs waiting for printing

Workers waiting to punch a time clockWorkers waiting to punch a time clock

Customers in line at a driveCustomers in line at a drive--up windowup window

Drivers waiting to pay a highway tollDrivers waiting to pay a highway toll Skiers waiting for a chair liftSkiers waiting for a chair lift

Airplanes waiting to take offAirplanes waiting to take off


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Waiting Line AnalysisWaiting Line AnalysisWaiting Line AnalysisWaiting Line Analysis

Assists managers in determining:Assists managers in determining:

How many servers to useHow many servers to use

Likelihood a customer will have to waitLikelihood a customer will have to wait

Average time a customer will waitAverage time a customer will wait Average number of customers waitingAverage number of customers waiting

Waiting line space neededWaiting line space needed

Percentage of time all servers are idlePercentage of time all servers are idle


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Waiting Line TerminologyWaiting Line TerminologyWaiting Line TerminologyWaiting Line Terminology

QueueQueue -- a waiting linea waiting line

ChannelsChannels -- number of waiting lines in a queuingnumber of waiting lines in a queuing

systemsystem

Service phasesService phases number of steps in service processnumber of steps in service process Arrival rateArrival rate ((PP)) -- rate at which persons or thingsrate at which persons or things

arrive (in arrivals per unit of time)arrive (in arrivals per unit of time)

Service rateService rate ((QQ)) -- rate that arrivals are serviced (inrate that arrivals are serviced (in

arrivals per unit of time)arrivals per unit of time)


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Waiting Line TerminologyWaiting Line TerminologyWaiting Line TerminologyWaiting Line Terminology

Queue disciplineQueue discipline -- rule that determines the order inrule that determines the order inwhich arrivals are servicedwhich arrivals are serviced

Queue lengthQueue length number of arrivals waiting for servicenumber of arrivals waiting for service

Time in systemTime in system an arrivals waiting timean arrivals waiting time andandservice timeservice time

UtilizationUtilization degree to which any part of the servicedegree to which any part of the service

system is occupied by an arrivalsystem is occupied by an arrival


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Queuing System StructuresQueuing System StructuresQueuing System StructuresQueuing System Structures

Single PhaseSingle Phase -- Single ChannelSingle Channel

Single PhaseSingle Phase -- MultichannelMultichannel

SS11

SS11

SS22

SS33


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Queuing System StructuresQueuing System StructuresQueuing System StructuresQueuing System Structures

MultiphaseMultiphase -- Single ChannelSingle Channel

MultiphaseMultiphase -- MultichannelMultichannel

SS1212SS1111

SS1212SS1111

SS2222

SS2121

SS3232SS3131


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Definitions of Queuing System VariablesDefinitions of Queuing System VariablesDefinitions of Queuing System VariablesDefinitions of Queuing System Variables

PP = average arrival rate= average arrival rate

1/1/PP = average time between arrivals= average time between arrivals

= average service rate for each server= average service rate for each server

1/1/ = average service time= average service timenn11 = average number of arrivals waiting= average number of arrivals waiting

nnSS = average number of arrivals in the system= average number of arrivals in the system

tt11

= average time arrivals wait= average time arrivals wait

ttSS = average time arrivals are in the system= average time arrivals are in the system

PPnn

= probability of exactly= probability of exactly nn arrivals in the systemarrivals in the system


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Model 1Model 1

Single channelSingle channel

Single phaseSingle phase

Poisson arrivalPoisson arrival--rate distributionrate distribution Poisson servicePoisson service--rate distributionrate distribution

Unlimited maximum queue lengthUnlimited maximum queue length

Examples:Examples:

SingleSingle--booth theatre ticket salesbooth theatre ticket sales SingleSingle--scanner airport security stationscanner airport security station

Queuing ModelsQueuing ModelsQueuing ModelsQueuing Models


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Example: Queuing Model 1Example: Queuing Model 1Example: Queuing Model 1Example: Queuing Model 1

Jim Beam pulls stock from his warehouse shelvesJim Beam pulls stock from his warehouse shelvesto fill customer orders. Customer orders arrive at ato fill customer orders. Customer orders arrive at a

mean rate of 20 per hour. The arrival rate is Poissonmean rate of 20 per hour. The arrival rate is Poisson

distributed. Each order received by Jim requires andistributed. Each order received by Jim requires an

average of two minutes to pull. The service rate isaverage of two minutes to pull. The service rate isPoisson distributed also.Poisson distributed also.

Questions to follow Questions to follow


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Service Rate DistributionService Rate Distribution

QuestionQuestion

What is Jims mean service rate per hour?What is Jims mean service rate per hour?

AnswerAnswerSince Jim can process an order in an average timeSince Jim can process an order in an average time

of 2 minutes (= 2/60 hr.), then the mean serviceof 2 minutes (= 2/60 hr.), then the mean service

rate, , equals 1/(mean service time), or60/2 =rate, , equals 1/(mean service time), or60/2 =

30/hr.30/hr.


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Average Time in the SystemAverage Time in the System

QuestionQuestion

What is the average time an order must wait fromWhat is the average time an order must wait fromthe time Jim receives the order until it is finishedthe time Jim receives the order until it is finishedbeing processed (i.e. its turnaround time)?being processed (i.e. its turnaround time)?

AnswerAnswer

WithWith PP = 20 per hour and= 20 per hour and QQ = 30 per hour, the= 30 per hour, the

average time an order waits in the system is:average time an order waits in the system is:ttSS = 1/(= 1/( -- PP ) = 1/(30) = 1/(30 -- 20)20)

= 1/10 hour or 6 minutes= 1/10 hour or 6 minutes


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Average Length of QueueAverage Length of Queue

QuestionQuestion

What is the average number of orders Jim hasWhat is the average number of orders Jim haswaiting to be processed?waiting to be processed?

AnswerAnswer

The average number of orders waiting in theThe average number of orders waiting in thequeue is: nqueue is: n11 == PP

22/[(/[( -- PP)])]

= (20)= (20)22

/[(30)(30/[(30)(30--20)]20)]= 400/300= 400/300

= 4/3 or 1.33 orders= 4/3 or 1.33 orders


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Utilization FactorUtilization Factor

QuestionQuestion

What percentage of the time is Jim processingWhat percentage of the time is Jim processingorders?orders?

AnswerAnswer

The percentage of time Jim is processing orders isThe percentage of time Jim is processing orders isequivalent to the utilization factor,equivalent to the utilization factor, PP//QQ. Thus, the. Thus, the

percentage of time he is processing orders is:percentage of time he is processing orders is:PP//QQ = 20/30= 20/30

= 2/3 or 66.67%= 2/3 or 66.67%


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Model 2Model 2 Single channelSingle channel


Poisson arrivalPoisson arrival--rate distributionrate distribution

Constant service rateConstant service rate


Examples:Examples:

SingleSingle--booth automatic car washbooth automatic car wash Coffee vending machineCoffee vending machine


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The mechanical pony ride machine at theThe mechanical pony ride machine at theentrance to a very popular Jentrance to a very popular J--Mart store provides 2Mart store provides 2minutes of riding for $.50. Children (accompanied ofminutes of riding for $.50. Children (accompanied ofcourse!) wanting to ride the pony arrive according tocourse!) wanting to ride the pony arrive according to

a Poisson distribution with a mean rate of 15 pera Poisson distribution with a mean rate of 15 perhour.hour.

a) What fraction of the time is the pony idle?a) What fraction of the time is the pony idle?

b) What is the average number of children waiting tob) What is the average number of children waiting to

ride the pony?ride the pony?c) What is the average time a child waits for a ride?c) What is the average time a child waits for a ride?


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Fraction of Time Pony is IdleFraction of Time Pony is Idle

PP = 15 per hour= 15 per hour

QQ = 60/2 = 30 per hour= 60/2 = 30 per hour

Utilization =Utilization = PP//QQ = 15/30 = .5= 15/30 = .5

Idle fraction = 1Idle fraction = 1 Utilization = 1Utilization = 1 -- .5 = .5.5 = .5


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Average Number of children Waiting for a RideAverage Number of children Waiting for a Ride

Average Time a Child Waits for a RideAverage Time a Child Waits for a Ride

or 1 minuteor 1 minute

1

15n . 5 children

15!

1

15t = = .01667 hours

2(-) 2(30)(30 - 15)!


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Model 3Model 3 Single channelSingle channel



Poisson servicePoisson service--rate distributionrate distribution

Limited maximum queue lengthLimited maximum queue length

Examples:Examples:

Auto repair shop with limited parking spaceAuto repair shop with limited parking space Bank driveBank drive--thru with limited waiting lanethru with limited waiting lane


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Model 4Model 4 Multiple channelMultiple channel



Poisson servicePoisson service--rate distributionrate distribution


Examples:Examples:

Expressway exit with multiple toll boothsExpressway exit with multiple toll booths Bank with multiple teller stationsBank with multiple teller stations


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Scheduling CustomerScheduling Customer--asas--Product ServicesProduct ServicesScheduling CustomerScheduling Customer--asas--Product ServicesProduct Services

Wide range of complexityWide range of complexity

Every facet designed around the customerEvery facet designed around the customer

Highly trained, motivated, and effective workforceHighly trained, motivated, and effective workforce

critical to successcritical to success WaitingWaiting--line analysis can be helpful in determiningline analysis can be helpful in determining

staffing levelsstaffing levels

In more complex operations, simulation is a helpfulIn more complex operations, simulation is a helpful

tool in scheduling resourcestool in scheduling resources


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Reasons for Simulating OperationsReasons for Simulating OperationsReasons for Simulating OperationsReasons for Simulating Operations

Experimentation with the real system is impossible,Experimentation with the real system is impossible,impractical, or uneconomical.impractical, or uneconomical.

System is so complex that mathematical formulasSystem is so complex that mathematical formulas

cannot be developed.cannot be developed.

Values of the systems variables are not known withValues of the systems variables are not known with

certainty.certainty.

Problem under consideration involves the passage ofProblem under consideration involves the passage of

time and simulation could be fastertime and simulation could be faster


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Procedures of Computer SimulationProcedures of Computer SimulationProcedures of Computer SimulationProcedures of Computer Simulation

Define the problem.Define the problem. Develop and computerDevelop and computer--program a model of problem.program a model of problem.

Identify the variables and parameters.Identify the variables and parameters.

Specify the decision rules.Specify the decision rules.

Gather data and specify variables and parameters.Gather data and specify variables and parameters.

Specify timeSpecify time--incrementing procedures.incrementing procedures.

Specify summarizing procedures.Specify summarizing procedures.

Process the simulation.Process the simulation. Evaluate the results of the simulation.Evaluate the results of the simulation.

Recommend a course of action.Recommend a course of action.


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Simulation ExampleSimulation ExampleSimulation ExampleSimulation Example

Whenever an international plane arrives atWhenever an international plane arrives atLincoln airport the two customs inspectors on dutyLincoln airport the two customs inspectors on duty

set up operations to process the passengers.set up operations to process the passengers.

Incoming passengers must first have theirIncoming passengers must first have their

passports and visas checked. This is handled by onepassports and visas checked. This is handled by one

inspector. The time required to check a passenger'sinspector. The time required to check a passenger's

passports and visas can be described by thepassports and visas can be described by the

probability distribution on the next slide.probability distribution on the next slide.


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Time Required toTime Required to

Check a Passenger'sCheck a Passenger's

Passport and VisaPassport and Visa ProbabilityProbability

20 seconds20 seconds.20

.20

40 seconds40 seconds .40.40




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After having their passports and visas checked,After having their passports and visas checked,the passengers next proceed to the second customsthe passengers next proceed to the second customs

official who does baggage inspections. Passengersofficial who does baggage inspections. Passengers

form a single waiting line with the official inspectingform a single waiting line with the official inspecting

baggage on a first come, first served basis.baggage on a first come, first served basis.


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The time required for baggage inspection has theThe time required for baggage inspection has thefollowing probability distribution:following probability distribution:

Time Required ForTime Required For

Baggage InspectionBaggage Inspection ProbabilityProbability

No Time .25No Time .25

1 minute .601 minute .60

2 minutes .102 minutes .10

3 minutes .053 minutes .05


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Random Number MappingRandom Number Mapping

Time Required toTime Required to

Check a Passenger's RandomCheck a Passenger's Random

Passport and VisaPassport and Visa ProbabilityProbability NumbersNumbers

20 seconds .20 0020 seconds .20 00 -- 1919

40 seconds .40 2040 seconds .40 20 -- 5959

60 seconds .30 6060 seconds .30 60 -- 8989

80 seconds .1080 seconds .10 9090 -- 9999


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Random Number MappingRandom Number Mapping

Time Required For RandomTime Required For Random

Baggage InspectionBaggage Inspection ProbabilityProbability NumbersNumbers

No Time .25 00No Time .25 00 -- 24241 minute .60 251 minute .60 25 -- 8484

2 minutes .10 852 minutes .10 85 -- 9494

3 minutes .05 953 minutes .05 95 -- 9999


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NextNext--Event Simulation RecordsEvent Simulation Records

For each passenger the following information must beFor each passenger the following information must be

recorded:recorded:

When his service begins at the passport controlWhen his service begins at the passport controlinspectioninspection

The length of time for this serviceThe length of time for this service

When his service begins at the baggage inspectionWhen his service begins at the baggage inspection

The length of time for this serviceThe length of time for this service


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Time RelationshipsTime Relationships

Time a passenger begins serviceTime a passenger begins service

by the passport inspectorby the passport inspector

= (Time the previous passenger= (Time the previous passengerstarted passport service)started passport service)

+ (Time of previous passenger's+ (Time of previous passenger's

passport service)passport service)


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Time RelationshipsTime Relationships

Time a passenger begins serviceTime a passenger begins service

by the baggage inspectorby the baggage inspector

(If passenger does not wait for baggage inspection)(If passenger does not wait for baggage inspection)= (Time passenger completes service= (Time passenger completes service

with the passport control inspector)with the passport control inspector)

(If the passenger does wait for baggage inspection)(If the passenger does wait for baggage inspection)

= (Time previous passenger completes= (Time previous passenger completes

service with the baggage inspector)service with the baggage inspector)


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Time RelationshipsTime RelationshipsTime a customer completes serviceTime a customer completes service

at the baggage inspectorat the baggage inspector

= (Time customer begins service with= (Time customer begins service withbaggage inspector)baggage inspector)

+ (Time required for baggage inspection)+ (Time required for baggage inspection)


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A chartered plane from abroad lands at LincolnA chartered plane from abroad lands at LincolnAirport with 80 passengers. Simulate the processingAirport with 80 passengers. Simulate the processing

of the first 10 passengers through customs.of the first 10 passengers through customs.


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Simulation Worksheet (partial)Simulation Worksheet (partial)

Passport ControlPassport Control Baggage InspectionsBaggage Inspections

Pass. Time Ran. Serv. Time Time Ran. Serv. TimePass. Time Ran. Serv. Time Time Ran. Serv. Time

Num.

Beg.

Num.

Time End Beg.

Num.

Time EndNum.

Beg.

Num.

Time End Beg.

Num.

Time End1 0:00 93 1:20 1:20 1:20 13 0:00 1:201 0:00 93 1:20 1:20 1:20 13 0:00 1:20

2 1:20 63 1:00 2:20 2:20 08 0:00 2:202 1:20 63 1:00 2:20 2:20 08 0:00 2:20

3 2:20 26 :40 3:00 3:00 60 1:00 4:003 2:20 26 :40 3:00 3:00 60 1:00 4:00

43:00 1

6:20 3:20

4:00 13 0:00

4:00

43:00 1

6:20 3:20

4:00 13 0:00

4:00

5 3:20 21 :40 4:00 4:00 68 1:00 5:005 3:20 21 :40 4:00 4:00 68 1:00 5:00


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Simulation Worksheet (continued)Simulation Worksheet (continued)

Passport ControlPassport Control Baggage InspectionsBaggage Inspections

Pass. Time Ran. Serv. Time Time Ran. Serv. TimePass. Time Ran. Serv. Time Time Ran. Serv. Time

Num.

Beg.

Num.

Time End Beg.

Num.

Time EndNum.

Beg.

Num.

Time End Beg.

Num.

Time End6 4:00 26 :40 4:40 5:00 40 1:00 6:006 4:00 26 :40 4:40 5:00 40 1:00 6:00

7 4:40 70 1:00 5:40 6:00 40 1:00 7:007 4:40 70 1:00 5:40 6:00 40 1:00 7:00

8 5:40 55 :40 6:20 7:00 27 1:00 8:008 5:40 55 :40 6:20 7:00 27 1:00 8:00

9 6:20 72 1:00 7:20 8:00 23 0:00 8:009 6:20 72 1:00 7:20 8:00 23 0:00 8:00

10 7:20 89 1:00 8:20 8:20 64 1:00 9:2010 7:20 89 1:00 8:20 8:20 64 1:00 9:20


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ExplanationExplanationFor example, passenger 1 begins being served byFor example, passenger 1 begins being served by

the passport control inspector immediately. Histhe passport control inspector immediately. His

service time is 1:20 (80 seconds) at which time heservice time is 1:20 (80 seconds) at which time he

goes immediately to the baggage inspector whogoes immediately to the baggage inspector who

waves him through without inspection.waves him through without inspection.


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ExplanationExplanationPassenger 2 begins service with passportPassenger 2 begins service with passport

inspector 1:20 minutes (80 seconds) after arrivinginspector 1:20 minutes (80 seconds) after arriving

there (as this is when passenger 1 is finished) andthere (as this is when passenger 1 is finished) and

requires 1:00 minute (60 seconds) for passportrequires 1:00 minute (60 seconds) for passportinspection. He is waved through baggage inspectioninspection. He is waved through baggage inspection

as well.as well.

This process continues in this manner.This process continues in this manner.


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QuestionQuestionHow long will it take for the first 10 passengersHow long will it take for the first 10 passengers

to clear customs?to clear customs?

AnswerAnswer

Passenger 10 clears customs after9 minutes andPassenger 10 clears customs after9 minutes and

20 seconds.20 seconds.


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QuestionQuestionWhat is the average length of time a customerWhat is the average length of time a customer

waits before having his bags inspected after he clearswaits before having his bags inspected after he clears

passport control? How is this estimate biased?passport control? How is this estimate biased?


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AnswerAnswerFor each passenger calculate his waiting time:For each passenger calculate his waiting time:

(Baggage Inspection Begins)(Baggage Inspection Begins) -- (Passport Control(Passport Control

Ends)Ends) =0+0+0+40+0+20+20+40+40+0 = 120=0+0+0+40+0+20+20+40+40+0 = 120

seconds.seconds.

120/10 = 12 seconds per passenger.120/10 = 12 seconds per passenger.

This is a biased estimate because we assume thatThis is a biased estimate because we assume that

the simulation began with the system empty. Thus,the simulation began with the system empty. Thus,the results tend to underestimate the average waitingthe results tend to underestimate the average waiting

time.time.


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WrapWrap--Up: WorldUp:World--Class PracticeClass PracticeWrapWrap--Up: WorldUp:World--Class PracticeClass Practice

Successful companies have:Successful companies have: Adapted advanced and wellAdapted advanced and well--known planning,known planning,

analyzing, and controlling approaches firstanalyzing, and controlling approaches firstdeveloped in manufacturingdeveloped in manufacturing

Recognized the unique properties of serviceRecognized the unique properties of serviceoperations and developed novel managementoperations and developed novel managementapproaches for these operationsapproaches for these operations

Classify service operations into three types... quasiClassify service operations into three types... quasi

manufacturing, customermanufacturing, customer--asas--participant, orparticipant, orcustomercustomer--asas--product...provides framework forproduct...provides framework foranalysis.analysis.


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WrapWrap--Up:WorldUp:World--Class PracticeClass PracticeWrapWrap--Up:WorldUp:World--Class PracticeClass Practice

Factors that create satisfied customersFactors that create satisfied customers Extrinsic quality of servicesExtrinsic quality of services

The facilities...comfort, convenience, andThe facilities...comfort, convenience, andatmosphereatmosphere

The chemistry between customer and people inThe chemistry between customer and people inservice system...friendliness and courtesyservice system...friendliness and courtesy

Skill, competence, and professionalism of theSkill, competence, and professionalism of thepersonnelpersonnel

The value of the service; cost relative to theThe value of the service; cost relative to thequantity of services receivedquantity of services received


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End of Chapter 9End of Chapter 9End of Chapter 9End of Chapter 9

Documents

Ch09 Service Opera Ti Ions