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Simulation Basics (1)

Apr 14, 2018

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    Dr. Pramod. M1

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    A set of integrated resources (machinery, labourer,

    equipment, information, and tools) that process raw

    material as input and produce final products as

    outputs.

    Its Purpose:

    Meet customer requirements

    Add Value

    At Minimum cost High Quality and Reliable

    Environmentally Friendly

    2

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    The responsibilities of management are: Establish priorities

    Utilise resources

    Monitor Performance

    Measure Performance

    Improve productivity (yield) and efficiency(input/output)

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    Production Machines, tools, fixtures, and other

    hardware equipment

    Material Handling Systems

    Loading and unloading (batch control)

    Positioning (manual, automated)

    Transporting (conveyors, transporters)

    Temporary storage (buffers)

    Computer Control Systems (SCADA, Robotics,Scheduling, Safety Monitoring, Quality, )

    Human Resources

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    Types of operations

    Number of workstations and system layout

    Product variety

    Level of automation

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    Processing operations: Working on individual parts

    (e.g. metal sheets, rolling, machining, drilling,

    treating, painting, etc.)

    Assembly operations: combining and putting parts

    together e.g. (mounting gearbox, engines dressing,

    Trimming shops in car factories, etc.)

    Type of parts and products: The specification of the

    material and also the method of processing the part

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    Key factorin classification scheme

    Determines main performance factors such as

    capacity, capability, efficiency, productivity,utilisation, cost per unit, and maintainability

    Determines the complexity of operations

    Arrangement of workstations is called System

    Layout

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    Type I: Single Station where (n = 1) Type II: Multiple Stations with fixed routings

    where (n > 1)

    Type III: Multiple Stations with variable routing

    where (n >1)

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    Characteristics Product Process Group (Cell) Fixed Pos.

    Throughput time Low High Low Medium

    WIP Low High Low Medium

    Skill Levels Choice High Med-High Mixed

    Product Flexibility Low High Med-High High

    Demand Flexibility Medium High Medium Medium

    Machine Utilisation High Med-Low Med-High Medium

    Operator Utilisation High High High Medium

    Production cost/unit Low High Low High

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    First Law (Littles Law): in a steady state system,WIP = Production Rate x Throughput Time

    Second Law: Matter is conserved

    Raw material enter the system (input) and finished products exitthe system (output). Any remaining or rejected parts need to beaccounted for.Therefore the summation of entry should be equal:-Total Material

    Entry (input) = Finished Parts (output) + Removed Material +

    Disposed Material + Recycled Material

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    Third Law: The larger the system the less reliableit is

    Fourth Law: Objects decay

    Both hardware and software objects decay over time,they need maintenance and replacement

    Fifth Law: Exponential growth in complexityComplexity increases with a larger rate when

    components are added to the system.

    Sixth Law: Technology advances

    Natural evolution to better material, processes andinformation

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    Principles of Manufacturing Systems

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    Seventh Law: System components appear to behaverandomlyEvents can not be precisely predicted and this needs to be observed in anysystem design, development and analysis

    Eighth Law: Limits of human rationalityHuman beings have limitations, this should be accounted for in any systemanalysis

    Ninth Law: Combining, Simplifying, and Eliminating

    save Time, Money and EffortKISS concept Good models are abstract, straight to the point, accurateand specified objectives.

    Over complication is Lethal

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    Simulation is a powerful tool for modeling and

    analysis of complex systems.

    Many real life problems are difficult to study via

    analytical methods. But simulation model can be

    constructed and run for all types of problems to

    generate information on the system performance-

    How well the system performs for a set of parameters How to optimize the system

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    Used mainly as a decision making tool

    Until 1980s , simulation was costly and time

    consuming but with the advent of PC and

    powerful hardware- fast, low cost, interactive,

    visualization and animation oriented simulation

    was possible

    Arena general purpose visual simulation

    environment

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    Simplified representation of a system under study

    Experiment with the system with a set of goal like

    improve system design, cost benefit analysis,

    sensitivity analysis

    Representation describes system structure while

    histories generated describes system behavior.

    Model- simplified representation of a complex system

    to capture behavioral aspects interested to the analyst

    to gain insight into the behavior of the system--

    abstraction & simplification16

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    Evaluating a systems performance under ordinaryand unusual scenarios

    Predicting performance of experimental system

    design

    Ranking multiple design and their trade offs

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    Worldview is a philosophy-----two types : developer

    WV and user WV

    Developer WV----discrete event simulation

    paradigm, model possesses a state at any point in time and the state

    remains unchanged unless a simulation event occurs thenthe model undergoes transition.

    Model evolution is controlled by a clock and an event list,each event is a code which can change the state variableand schedule other events

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    Problem analysis and information collection-

    identification of input, performance measures,

    relationship among parameters, constraints, flow

    diagrams and trees...

    Data collection-

    estimate model input parameters and assumptions

    Model construction- either using computer language or using special

    simulation environment like arena

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    Model verification-

    make sure that the model is correctly constructed as

    per specification

    Model validation-

    fit of the model to empirical data. Good fit means

    performance measure predicted by the model match

    or agree reasonably with those in real life systems

    Designing and conducting simulation runs

    Output analysis & Final recommendation

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    Discrete event simulation Probability and statistics

    Random number generation

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    Provides an integrated framework for building

    simulation models in a wide variety of

    applications. It integrates all the functions needed

    for a successful simulation including:

    1. Animation

    2. analysis of inputs and outputs data

    3. model verificationinto one comprehensive environment.

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    Consists of modular templates build around SIMAN

    language constructs and visual front end SIMAN consists of two classes of objects- blocks and

    elements

    Blocks are logical constructs that represent operations(SEIZE/ RELEASE)

    Elements are objects that represent a facility

    (RESOURCES, QUEUES, TALLIES....)

    Arena fundamental modeling component is the

    modules which is a high level construct consisting of

    many SIMAN blocks and elements.

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    a unique collection of small example models that

    demonstrate a variety of modeling techniques and

    situations commonly encountered using Arena.

    SMARTs have been specifically designed for use as

    a training or reference tool to assist you in your

    model-building efforts .

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    Entities : In every simulation model entities are

    objects under a particular process, and they move

    along the system.

    Example: manufacturing raw material and products, banks

    customers, hospitals patients are the entities.

    In a typical Simulation project there can be one or

    many different types of entities.

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    Attributes : Are the characteristics of each entity

    and represent values associated with individual

    entities. In a typical system we can define as many attributes as we

    need for the entities. Example: length, or weight, or patients the type of the

    disease.

    Stations : Stations are boundaries where

    processing occurs in a system. Example: Production line a process is performed by a station

    i.e. drilling, milling, filling, etc. And in offices these boundariescould be departments.

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    Transporters : Entities move in the system via

    transporters.

    Transporters can be used to represent material handling or

    transfer of devices.

    Some examples for transporters are; AGVs, trucks, forks,

    cranks, carts, etc

    Conveyors : Conveyors are devices that move

    entities form one station to another in one direction.

    Such as escalators and horizontal conveyors.

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    Variables : Represent values that describe the

    characteristics of the system. These values are available to

    all entities.

    Used for many different kinds of things

    Travel time between all station pairs Number of parts in system (Work-in Process)

    Simulation clock (built-in Arena variable)

    Name, value of which theres only one copy for the whole model

    Not tied to entities

    Entities can access, change variables

    Some built-in by Arena, you can define others

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    Consider a single WS with an m/c of infinite buffer.

    jobs arrive randomly and wait in buffer if the m/c isbusy. The IAT are expo(30)min while PT are

    expo(24)min. (M/M/1 Queue). System simulated for

    10000 hrs Data:-

    IAT are expo(30)min

    PT are expo(24)min

    Simulation run time-10000 hrs

    Compare with theoretical results, estimate avg job

    delay in Q, avg no in Q and m/c utilization

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    Result:- (insufficient ) no of observations insufficient for adequate

    statistical confidence.

    Number busy- no of busy units of a resource

    Number schedule- resource capacity

    Inst utilization-utilization per resource unit= number busy/number

    scheduled

    For M/M/1- m/c utilization ==/ Where = job arrival rate = 1/30,

    And = job processing rate= 1/24

    = 0.8 (0.81 obtained through simulation)

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    Consider a manufacturing network of two workstations

    in series, consisting of an assembly workstationfollowed by a painting workstation, where jobs arrive

    at the assembly station with exponentially distributed

    inter-arrival times of mean 5 hours.

    the assembly process always has all the raw materials

    necessary to carry out the assembly operation the

    assembly time is uniformly distributed between 2 and 6

    hours

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    after the process is completed, a quality control test is

    performed, and past data reveal that 15% of the jobs

    fail the test and go back to the assembly operation for

    rework jobs that pass the test proceed to the painting

    operation that takes 3 hours for each unit.

    We are interested in simulating the system for 100,000

    hours estimating process utilizations, average job

    waiting times and average job flow times (the elapsed

    time for a job from start to finish)

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    Data- IAT=Expo(5)hr PT

    assembly=Unif(2,6)hr QC=85% True, 15% false --

    ---rework PT paint= 3 hrs

    Simulation time=100000hrs Attributes=Tnow, total

    rework Record= flow time=

    time between jobdeparture from paintand arrival time atassembly, reworks / job

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    time between arrival of successive batch is expo

    (30)min. Upon arrival at the prep area it is separated

    into 4 units which are processed individually from here.

    The processing at the prep area follows TRIA (3,5,10).

    The part is then sent to the sealer.

    At the sealer , the case is sealed and tested, the total

    time for these operations depends on the part type;

    TRIA (1,3,4)for part a and WEIB(2.5,5.3) for Part B.

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    91 % of the parts pass inspection and are transferred

    directly to the shipping dept.

    The remaining parts are transferred to the rework area

    where they are disassembled, repaired cleaned

    assembled and retested. 80 % of the parts are salvaged

    and passed on to the shipping dept and the rest is

    thrown out as scrap. time for rework follows expo

    (45)min independent of the part type. The system is

    run for 4 8 hr shifts or 1920 min

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    Travelers arrive at the main entrance door of an airline

    terminal according to an EXPO Interarrival time ofmean 1.6 min, with the first arrival at time 0.

    The travel time from entrance to check in is UNIF

    distributed between 2 and 3 min. at the check incounter travelers wait in a single line until one of the

    five agents is available to serve them.

    Check in time follows a WEINB distribution with

    parameters (7.76, 3.91). upon completion of their check

    in they are free to travel to their gates., simulation run

    time is 16 hrs .43

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    Data IAT passengers= EXPO(1.6)min

    Travel time to check in=UNIF (2,3)min Check in time =WIENB(7.76,3.91) min Simulation run time =16 hrs First arrival time =0 min

    Find:- avg time in system, no of passengers completing check

    in and avg length of check in Q

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    The emergency room of a small hospital operates

    around the clock. It is staffed by three receptionists at

    the reception office, and two doctors on the premises,

    assisted by two nurses. However, one additional doctor

    is on call at all times; this doctor is summoned when the

    patient workload up-crosses some threshold, and is

    dismissed when the number of patients to be examinedgoes down to zero, possibly to be summoned again

    later.

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    Patients arrive at the emergency room according to a

    Poisson process with mean interarrival time of 10 minutes.

    An incoming patient is first checked into the emergency

    room by a receptionist at the reception office. Check-in

    time is uniform between 6 and 12 minutes. Since critically ill

    patients get treatment priority over noncritical ones, each

    patient first undergoes triage in the sense that a doctordetermines the criticality level of the incoming patient in

    FIFO order.

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    The time spent to reach the treatment room is uniform

    between 1 and 3 minutes and the treatment time by a

    nurse is uniform between 3 and 10 minutes.

    Once treated by a nurse, a noncritical patient waits FIFO

    for a doctor to approve the treatment, which takes a

    uniform time between 5 to 10 minutes., all patients wait

    FIFO for an available doctor, but critical patients aregiven priority over noncritical ones.

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    Following treatment by a doctor, all patients are

    checked out FIFO at the reception office, which takes

    a uniform time between 10 and 20 minutes, following

    which the patients leave the emergency room.

    To estimate the requisite statistics, the hospital

    emergency room was simulated for a period of 1 year.

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    Model:- 2 segment ER segment, on call doc segment

    Data:- receptionist=3, doc=2, on call doc= 1, nurse= 2

    IAT patient=Poisson(10)min

    Check in time Patients=unif(6,12)min Triage Time= tri(3,5,15)min

    Critical patients =40%

    Treatment time for P crit=unif(20,30)min

    Travel time for p non cri= unif(1,3)min

    Treatment time for p non cri=unif(3,10)min

    Waiting time for all patient= unif (5,10)min

    Check out time for all patient= unif (10,20)min

    Simulation length= 1 year

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    Modeling Production Lines :-resource allocation

    problems- workload allocation and buffer capacity,

    productivity improvement measures, Modeling

    Machine Failures.

    Modeling Transportation Systems:-Designing new

    traffic routes and alternate routes to satisfy demand

    for additional road capacity, or eliminating bottlenecks

    and congestion points in existing routes, Designingtraffic patterns on the factory floor, Designing port

    facilities and material handling systems.

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    Modeling Computer Information Systems:-

    Modeling Supply Chain Systems:-Customer service

    levels, Average inventory levels and backorder

    levels, Rate and quantity of lost sales, Inventory

    management segment, Demand management

    segment.

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    The manufacturing facility is a production line composed

    of manufacturing stages consisting of workstations with

    intervening buffers to hold product flowing along the line.

    push regime:- where little attention is given to the

    finished-product inventory

    pull regime:- where the process only produces in response

    to specific demands

    storage limitations in workstations give rise to a

    bottleneck phenomenon, involving both blocking and

    starvation

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    Space limitations in a downstream workstation can,

    therefore, cause stoppages at upstream

    workstations a phenomenon known as blocking.

    some workstations may experience idleness due tolack of job flow from upstream workstations. This

    phenomenon is called starvation

    starvation tends to propagate forward to

    successive workstations located downstream in the

    production line.

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    Blocking and starvation are, in fact, the flip sides of

    a common phenomenon and tend to occur

    togethera bottleneck workstation

    MODELS OF PRODUCTION LINES

    Productivity losses are potentially incurred

    whenever machines are idle (blocked or starved)

    due to machine failures or bottlenecks originatingfrom excessive accumulation of inventories

    between workstations.

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    Design problems in production lines are primarily

    resource allocation problems. workload allocation and buffer capacity allocation for a given set of

    workstations with associated processing times

    Performance analysis of production lines strives to

    evaluate their performance measures as function of a

    set of system parameters. The most commonly used

    performance measures follow: Throughput, Average inventory levels in buffers Downtime probabilities Blocking probabilities at bottleneck workstations Average system flow times (also called manufacturing lead times)

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    Consider a generic packaging line for some product,

    such as a pharmaceutical plant producing a

    packaged medicinal product, or a food processing

    plant producing packaged foods or beverages.

    The line consists of workstations that perform the

    processes of filling, capping, labeling, sealing, and

    carton packing. Individual product units will be

    referred to simply as units.

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    We make the following assumptions:

    The filling workstation always has material in frontof it, so that it never starves. 2. The buffer space

    between workstations can hold at most five units. 3.

    A workstation gets blocked if there is no space in

    the immediate downstream buffer (manufacturing

    blocking).4. The processing times for filling,

    capping, labeling, sealing, and carton packing are

    6.5, 5, 8, 5, and 6 seconds, respectively.

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    Note that these assumptions render our packaging

    line a push-regime production. line. To keep matters

    simple, no randomness has been introduced into the

    system, that is, our packaging line is deterministic. It is

    worthwhile to elaborate and analyze the behavior of

    the packaging line understudy.

    The first workstation (filling) drives the system in

    that it feeds all downstream workstations with units.

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    Clearly, one of the workstations in the line is the

    slowest . The throughput of that workstation thencoincides with the throughput of the entire packaging

    line.

    Furthermore, workstations upstream of the slowest

    one will experience excessive buildup of WIP inventory

    in their buffers. In contrast, workstations downstream

    of the slowest one will always have lightly occupied or

    empty WIP inventory buffers.

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    machine failures of various kinds constitute an

    important source of idleness and variability . efficient

    operation requires that downtimes be minimized, since

    these represent loss of production time.

    Failures that occur while machines are actually

    processing jobs are called operation dependent and the

    new breed of highly computerized machines may fail atany time, regardless of machine status. Such failures

    are called operation independent

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    Suppose that Filling Process in the packaging line

    model of fails randomly and that it needs an

    adjustment after every 250 departures from the

    workstation.

    Assume that uptimes are exponentially distributed

    with a mean of 50 hours, while repair times are

    uniformly distributed between 1.5 hours to 3 hours.

    Also, the aforementioned adjustment time is uniformly

    distributed between 10 minutes to 25 minutes.

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    Assume further that Packing Process can also experience

    random mechanical failures, and downtimes are triangularly

    distributed with a minimum of 75 minutes, a maximum of 2

    hours, and a mode at 90 minutes.

    The corresponding uptimes are exponentially distributed

    with a mean of 25 hours. Finally, assume that random failures

    occur only while the machines are busy (operation-

    dependent failures).

    We shall refer to the modified packaging line model as the

    failure-modified model

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    how failures in the failure-modified model are

    specified in a dialog spreadsheet for the Failure

    module from the Advanced Process template

    panel. Arena provides a mechanism for defining

    resource states and for linking them to failures/

    stoppages in the form of the StateSet spreadsheet

    module from the Advanced Process template

    panel.

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    Monte Carlo simulation is an invaluable tool for

    studying transportation systemsand solving their

    attendant problems

    Some common examples are listed below: Designing new traffic routes and alternate routes to satisfy

    demand for additional road capacity, or eliminatingbottlenecks and congestion points in existing routes byappropriate placement of traffic lights and tollbooths.

    Designing traffic patterns on the factory floor, includingtransporters and conveyors, for efficient movement of rawmaterial and product.

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    The PickStation module allows entities to select a

    destination Station module using a selection

    criterion, such as the minimal or maximal queue size,

    number of busy resource units, or an arbitraryexpression.

    Alternatively, an entity can be endowed with an

    itinerary using the Sequence module to specify a

    sequence of Station modules

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    A Job Shop producing 3 types of Gears; G1, G2, G3. Job

    Shop consists of Arrival Dock, Milling , Drilling , Paint

    Shop, Polishing Area, Shop Exit

    Gear Jobs arrive in batches of 10 units. Their inter-arrival

    times are uniformly distributed between 400 and 600

    minutes. Of arriving batches, 50% are G1, 30% are G2, 20%

    are G3.

    Each gear type has different operation sequence. Gears

    are transported by Two trucks running at a constant

    speed of 100 feet/minute. Each truck can carry only one

    gear at a time.73

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    Transport Procedure:

    The Transport starts from Arrival Dock When a job is complete at a location, the gear is placed into

    an output buffer. A transport request is made for a truck, and the gear waits

    for the truck to arrive.

    Among the two trucks, the preference will be for the onewhich is closest to the requested location.

    The transported job is placed in the input buffer of nextstation.

    After all operations, the finished gear departs fromthe job shop via the Shop Exit.

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    Assumptions:- Transporter (Truck) speed is same for both loaded and

    empty. The freed transporter stays at the destination station until

    requested by another station. The Job Shop works for 24 hours a day in 3 shifts at 8 hours

    each.

    Find:-

    Gear flow time

    Gear delays at operation location Resource utilization Improvements

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    This example illustrates bulk port operations, using the notions

    of station, entity routing among stations, entity pick-up and

    drop-off by another entity, and the control of entity

    movements using logical gating. It concerns a bulk material

    port, called Port Tamsar, at which cargo ships arrive and wait

    to be loaded with coal for their return journey. Cargo ship

    movement in port is governed by tug boats, which need to be

    assigned as a requisite resource. The port has a single berth

    where the vessels dock, and a single ship loader that loads the

    ships.

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    A schematic representation of the layout of Port Tamsar

    is depicted in Figure 13.2. Port Tamsar operates

    continually 24 hours a day and 365 days a year. The

    annual coal production plan calls for nominal

    deterministic ship arrivals at the rate of one ship every

    28 hours. However, ships usually do not arrive on time

    due to weather conditions, rough seas, or otherreasons, and consequently, each ship is given a 5-day

    grace period commonly referred to as the lay period.

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    We assume that ships arrive uniformly in their lay

    periods and queue up FIFO (if necessary) at an offshoreanchorage location, whence they are towed into port by

    a single tug boat as soon as the berth becomes available.

    The tug boat is stationed at a tug station located at a

    distance of 30 minutes away from the offshore

    anchorage.

    Travel between the offshore anchorage and the berth

    takes exactly 1 hour.

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    We assume that there is an uninterrupted coal supply to

    the ship loader at the coal-loading berth, and that ship

    loading times are uniformly distributed between 14 and

    18 hours.

    Once a ship is loaded at the berth, the tug boat tows it

    away to the offshore anchorage, whence the boat

    departs with its coal for its destination.

    Departing vessels are accorded higher priority in seizing

    the tug boat.

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    An important environmental factor in many port

    locations around the world is tidal dynamics. Cargo shipsare usually quite large and need deep waters to get into

    and out of port.

    Obviously, water depth increases with high tide and

    decreases with low tide, where the time between two

    consecutive high tides is precisely 12 hours.

    We assume that ships can go in and come out of port

    only during the middle 4 hours of high tide. Thus, the

    tidal window at the port is closed for 8 hours and open

    for 4 hours every 12 hours.82

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    We wish to simulate Port Tamsar for 1 year (8760

    hours) to estimate berth and ship loader utilization,

    as well as the expected port time per ship. We

    mention parenthetically that although a number of

    operating details have been omitted to simplify the

    modeling problem, the foregoing description is

    quite realistic and applicable to many bulk material

    ports and container ports around the world.

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    An Arena model of Port Tamsar consists of four

    main segments: (1) ship arrivals, (2) tugboat

    operations, (3)coal-loading operations at the berth,

    and (4) tidal window modulation. These will be

    described next in some detail along with

    simulation results.

    84

    1

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    2

    3

    4

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    This example concerns a transportation system

    consisting of a toll plaza on the New Jersey Turnpike,and aims to study the queueing delays resulting from

    toll collection.

    The toll plaza consists of two exact change (EC) lanes,

    two cash receipt (CR) lanes, and one easy pass (EZP)

    lane. Arriving vehicles are classified into three groups as

    follows: 1. Fifty percent of all arriving cars go to EC lanes, and their

    normal service time distribution is Norm(4.81, 1.01).

    h f ll l d h

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    2. Thirty percent of all arriving cars go to CR lanes, and theirservice time distribution is 5 Logn(4.67, 2.26).

    3. Twenty percent of all arriving cars go to EZP lanes, and their

    service time distribution is 1.18 4.29 Beta(2.27, 3.02).

    To simplify matters, we assume that an incoming car

    always joins the shortest queue in its category (EC, CR,

    or EZP).

    We further assume that no jockeying between queues

    takes place. That is, once a car joins a queue in front of a

    tollbooth, it never switches to another queue.

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    Traffic congestion is distinctly non stationary, varying

    widely by time of day. As expected, traffic is heavierduring the morning rush hour (6 A.M.9 A.M.) and the

    evening rush hour (4 P.M.7 P.M.), and tapers off during

    off-peak hours.

    Table 13.1 summarizes vehicle interarrival time

    distributions over each 24-hour period. The number of

    operating cash receipt booths varies over time.

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    Since such booths must be manned, and therefore are

    expensive to operate, one of them is closed during the

    off-peak hours.

    Only during morning and evening rush hours do all

    cash receipt booths remain open.

    Typical performance analysis objectives for the toll

    plaza system address the following issues:

    What would be the impact of additional traffic on car

    delays?

    Would adding another booth markedly reduce waiting

    times?89

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    Could some booths be closed during light traffic hours without

    appreciably increasing waiting times?

    What would be the impact of converting some cash receipt

    booths to exact change booths or to easy pass booths?

    How would waiting times be reduced if both cash receipt booths

    were to be kept open at all times?

    Of course, additional issues may be specific to

    particular toll plazas under study, but in our case we

    wish to address the last issue in the list, using the

    performance metrics of average time to pass through

    the system and booth utilization.

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    The model can be decomposed into the following

    segments: creation of car entities from the appropriatedistributions over various time periods, dispatching a

    car to the appropriate tollbooth with the shortest

    queue, and serving incoming cars.

    To this end, we use the Set construct to facilitate

    modeling of module sets (model components) with

    analogous logic (e.g., multiple tollbooths).

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    Simulation Modeling and ArenaJanuary 2009ISBN 978 0 470 09726 7

    Charu Chandra, University of Michigan - Dearborn Translations of Simulation with Arena, 3rdEdition

    http://www.wiley.com/WileyCDA/WileyTitle/productCd-0470097264.htmlhttp://www.wiley.com/WileyCDA/WileyTitle/productCd-0470097264.htmlhttp://www.wiley.com/WileyCDA/WileyTitle/productCd-0470097264.htmlhttp://www.wiley.com/WileyCDA/WileyTitle/productCd-0470097264.htmlhttp://www.wiley.com/WileyCDA/WileyTitle/productCd-0470097264.htmlhttp://www.wiley.com/WileyCDA/WileyTitle/productCd-0470097264.htmlhttp://www.wiley.com/WileyCDA/WileyTitle/productCd-0470097264.htmlhttp://www.wiley.com/WileyCDA/WileyTitle/productCd-0470097264.htmlhttp://www.wiley.com/WileyCDA/WileyTitle/productCd-0470097264.htmlhttp://www.wiley.com/WileyCDA/WileyTitle/productCd-0470097264.html
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    ISBN: 978-0-470-09726-7Manuel D. Rossetti, Associate Professor of IndustrialEngineering, University of Arkansas,Department of Industrial Engineering .Healthcare Operations ManagementMay 2008ISBN 13: 978-1-56793-288-1Daniel B. McLaughlin, DirectorCenter for BusinessExcellence in the Opus College of Business at theUniversity of St. ThomasJulie M. Hays, PhDSimulation Modeling and Analysis with Arena

    Academic PressISBN-13: 978-0-12-370523-5Tayfur Altiok, Professor, Department of IndustrialEngineering, Rutgers University [email protected] Melamed, Professor, Department ofManagement Science and Information ystems,Rutgers University [email protected] Process Analysis and Improvement: Tools andTechniquesMcGraw-Hill IrwinISBN: 0072857129 Marvin S Seppanen, Productive SystemsSameer Kumar, University of St. Thomas, Minneapolis

    EditionDr. Soemon Takakuwa (Japanese Translator)January 2005. McGraw Hill Publisher.ISBN 4-339-08246-5Moon Il Kyeong (Korean Translator)Kyobo Book Centre Publisher. January 2005ISBN 8970855122 Applied Simulation ModelingISBN: 0534381596Copyright year: 2003 Andrew Seila - University of GeorgiaVlatko Ceric - University of Zagreb

    Pandu Tadikamalla - University of Pittsburgh Introduction to Modeling and Simulation ofSystems with ArenaVisual BooksCopyright 2003 PortugueseISBN 85-7502-046-3

    93

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