Modeling Basic Operations and InputsWhat We’ll Do ...What We’ll Do ... (cont’d.)Electronic Assembly/Test System (Model 4-1)Part APart BRun Conditions, OutputDeveloping a Modeling ApproachBuilding the ModelPart A Create ModulePart B Create ModulePart A Attributes Assign ModulePart B Attributes Assign ModuleProcess Module ActionsPrep A Process ModulePrep B Process ModuleSealer Process ModuleSealer Inspection-Result Decide ModuleRework Process ModuleRework Inspection-Result Decide ModuleRecord ModulesShipped Parts Record ModuleDispose ModulesRun > Setup for Run ControlDifferent Part A, B Entity PicturesRunning the ModelViewing the ResultsModel 4-2: The Enhanced Electronic Assembly and Test SystemChange Run ConditionsSchedulesSchedules (cont’d.)Schedules (cont’d.)Resource FailuresResource Failures (cont’d.)FrequenciesFrequencies (cont’d.)Results of Model 4-2Utilizations – Some Fine PointsModel 4-3: Enhancing the AnimationChanging Animation QueuesChanging the Entity PicturesAdding Resource PicturesAdding Variables and PlotsModel 4-4: The Electronic Assembly and Test System with Part TransfersNew Arena ConstructsAdding the Route Logic – From ArrivalAdding the Remaining Route LogicWhy Not Just Add Delays?Altering the Animation – Station Markers, RoutesAltering the Animation – Entity PicturesInput Analysis: Specifying Model Parameters, DistributionsDeterministic vs. Random InputsCollecting DataUsing Data: Alternatives and IssuesFitting Distributions to Data with the Arena Input AnalyzerFitting Distributions to Data with the Arena Input Analyzer (cont’d.)Data Files for the Input AnalyzerThe Fit MenuThe Fit Menu (cont’d.)The Fit Menu (cont’d.)Some Issues in Fitting Input DistributionsNo Data?Cautions on Using Normal DistributionsNonstationary Arrival ProcessesNonstationary Arrival Processes (cont’d.)Multivariate and Correlated Input DataSimulation with Arena, 3rded. Chapter 4 – Modeling Basic Operations and Inputs Slide 1 of 66Modeling Basic Operations and InputsChapter 4Last revision June 7, 2003Simulation with Arena, 3rded. Chapter 4 – Modeling Basic Operations and Inputs Slide 2 of 66What We’ll Do ...• Model 4-1: Electronic assembly/test system Modeling approaches New Arena modules (Decide, Record)• Model 4-2: Enhanced electronic assembly/test Resource Schedules, States, and Failures Frequency outputs More on utilizations• Model 4-3: Enhancing the animation Queues, Entity Pictures, Resource Pictures Adding Plots and VariablesSimulation with Arena, 3rded. Chapter 4 – Modeling Basic Operations and Inputs Slide 3 of 66What We’ll Do ...(cont’d.)• Model 4-4: Adding entity travel times Modify with Stations, Transfers, Routes, animation of entity movement• Input analysis Specifying input distributions, parameters Deterministic vs. random input Collecting and using data Fitting input distributions via the Input Analyzer No data? Nonstationary arrival processes Multivariate and correlated input dataSimulation with Arena, 3rded. Chapter 4 – Modeling Basic Operations and Inputs Slide 4 of 66Electronic Assembly/Test System(Model 4-1)• Produce two different sealed elect. units (A, B)• Arriving parts: cast metal cases machined to accept the electronic parts• Part A, Part B – separate prep areas• Both go to Sealer for assembly, testing – then to Shipping (out) if OK, or else to Rework• Rework – Salvaged (and Shipped), or ScrappedSimulation with Arena, 3rded. Chapter 4 – Modeling Basic Operations and Inputs Slide 5 of 66Part A• Interarrivals: expo (5) minutes• From arrival point, proceed immediately to Part A Prep area Process = (machine + deburr + clean) ~ tria (1,4,8) minutes• Go immediately to Sealer Process = (assemble + test) ~ tria (1,3,4) min. 91% pass, go to Shipped; Else go to Rework• Rework: (re-process + testing) ~ expo (45) 80% pass, go to Salvaged; Else go to ScrappedSimulation with Arena, 3rded. Chapter 4 – Modeling Basic Operations and Inputs Slide 6 of 66Part B• Interarrivals: batches of 4, expo (30) min.• Upon arrival, batch separates into 4 individual parts• From arrival point, proceed immediately to Part B Prep area Process = (machine + deburr +clean) ~ tria (3,5,10)• Go to Sealer Process = (assemble + test) ~ weib (2.5, 5.3) min. , different from Part A, though at same station 91% pass, go to Shipped; Else go to Rework• Rework: (re-process + test) = expo (45) min. 80% pass, go to Salvaged; Else go to ScrappedSimulation with Arena, 3rded. Chapter 4 – Modeling Basic Operations and Inputs Slide 7 of 66Run Conditions, Output• Start empty & idle, run for four 8-hour shifts (1,920 minutes)• Collect statistics for each work area on Resource utilization Number in queue Time in queue• For each exit point (Shipped, Salvaged, Scrapped), collect total time in system (a.k.a. cycle time)Simulation with Arena, 3rded. Chapter 4 – Modeling Basic Operations and Inputs Slide 8 of 66Developing a Modeling Approach• Define pieces of model, modules, data structures, control logic• Appropriate level of detail – judgment call• Often multiple ways to model, represent logic• This model: Entities are the individual parts (two types) Separate Create modules for two part types Separate Process modules for each Prep area Process modules for Sealer and Rework, each followed by a Decide module (2-way by Chance) Depart modules for Shipped, Salvaged, Scrapped Attribute Sealer Time assigned after Creates in Assign modules (parts have different times at the Sealer) Record modules just before Departs for time in systemSimulation with Arena, 3rded. Chapter 4 – Modeling Basic Operations and Inputs Slide 9 of 66Building the Model• New model window• Attach Basic Process panel (if needed)• Place modules Create (x 2) Assign (x 2) Process (x 4) Decide (x 2) Record (x 3) Dispose (x 3)• Right click — repeat last action (place module)• Auto-Connect, or manually connect via Alternate strategy –place one module at a time, fill it out completelySimulation with Arena, 3rded. Chapter 4 – Modeling Basic Operations and Inputs Slide 10 of 66Part A Create Module• Name: Part A Arrive• Entity Type: Part A• Time Between Arrivals Type: Random (Expo)– Pull-down list with options Value: 5 Units: Minutes– Pull-down list with options• Default what’s not mentioned