Simulation with Arena, 4thed. Chapter 4 – Modeling Basic Operations and Inputs Slide 1 of 68f|ÅâÄtà|ÉÇIE406, I & IEUTKDr. Xueping LiUniversity of TennesseeModeling Basic Operations and InputsChapter 4What We’ll Do ...Simulation with Arena, 4thed. Chapter 4 – Modeling Basic Operations and Inputs Slide 2 of 68• 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 VariablesWhat We’ll Do ...(cont’d.)Simulation with Arena, 4thed. Chapter 4 – Modeling Basic Operations and Inputs Slide 3 of 68• Model 4-4: Adding entity travel times Stations, Transfers, Routes, animation of entity movement• Finding and fixing model errors• 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, 4thed. Chapter 4 – Modeling Basic Operations and Inputs Slide 4 of 68Electronic 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 ScrappedPart ASimulation with Arena, 4thed. Chapter 4 – Modeling Basic Operations and Inputs Slide 5 of 68• Interarrivals: expo (5) min.• From arrival point, go immediately to Part A Prep Process = (machine + deburr + clean) ~ tria (1,4,8) min.• 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) min. 80% pass, go to Salvaged; Else go to ScrappedPart BSimulation with Arena, 4thed. Chapter 4 – Modeling Basic Operations and Inputs Slide 6 of 68• Interarrivals: batches of 4, expo (30) min.• Upon arrival, batch breaks into 4 individual parts• 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 ScrappedRun Conditions, OutputSimulation with Arena, 4thed. Chapter 4 – Modeling Basic Operations and Inputs Slide 7 of 68• Start empty & idle, run for 32 hours• 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)Developing a Modeling ApproachSimulation with Arena, 4thed. Chapter 4 – Modeling Basic Operations and Inputs Slide 8 of 68• 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 systemBuilding the ModelSimulation with Arena, 4thed. Chapter 4 – Modeling Basic Operations and Inputs Slide 9 of 68• New model window• Attach Basic Process panel (if needed)• Place modules Create (× 2) Assign (× 2) Process (× 4) Decide (× 2) Record (× 3) Dispose (× 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 completelyPart A Create ModuleSimulation with Arena, 4thed. Chapter 4 – Modeling Basic Operations and Inputs Slide 10 of 68• 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 aboveOnce these entries are made, they are placed on the list for names of that type (Module Name, Entity Type, etc.) and will appear on future pull-down lists for that type of name.Part B Create ModuleSimulation with Arena, 4thed. Chapter 4 – Modeling Basic Operations and Inputs Slide 11 of 68• Name: Part B Arrive• Entity Type: Part B• Time Between Arrivals Type: Random (Expo)– Pull-down list with options Value: 30 Units: Minutes– Pull-down list with options• Entities per Arrival: 4Part A Attributes Assign ModuleSimulation with Arena, 4thed. Chapter 4 – Modeling Basic Operations and Inputs Slide 12 of 68• Name: Assign Part A Sealer and Arrive Time• Add button: Type: Attribute Attribute Name: Sealer Time New Value: TRIA(1, 3, 4)• Add button: Type: Attribute Attribute Name: Arrive Time New Value: TNOW (to compute time in system on exit)TNOW is the internal Arena variable name for the simulation clock; seeHelp > Arena Help > Contents >Variables, Functions, and Distributions > Variables > Date and Time VariablesPart B Attributes Assign ModuleSimulation with Arena, 4thed. Chapter 4 – Modeling Basic Operations and Inputs Slide 13 of 68• Name: Assign Part B Sealer and Arrive Time• Add button: Type: Attribute Attribute Name: Sealer Time New Value: WEIB(2.5, 5.3)• Add button: Type: Attribute Attribute Name: Arrive Time New Value: TNOWNames for things in Arena– Default names usually suggested– Names placed on appropriate pull-down lists for future reference– All names in a model must be unique (even across different kinds of objects)Prep A Process ModuleSimulation with Arena, 4thed. Chapter 4 – Modeling Basic Operations and Inputs Slide 14 of 68• Name: Prep A Process• Action: Seize Delay Release• Resources subdialog (Add button): Type: Resource (a pull-down option)