Waiting Lines and Simulation PDF

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Waiting Lines and Simulation...

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Waiting Lines and Simulation Analysis of waiting-line problems so far: 1. Arrivals = Poisson distribution or exponential interarrival times 2. Service times = exponential distribution 3. Service facilities = simple arrangement 4. Waiting line = unlimited 5. Priority discipline = first come, first served SimQuick Simulation: an easy-to-use package that is simply an Excel spreadsheet with some macros used for simple processes (e.g. waiting lines, inventory control, projects) Steps: 1. Draw flowchart of the process using SimQuick’s building blocks a. Entrance  arrival of customer b. Buffer  model for waiting lines c. Workstations d. Decision point (e.g. random selection of passenger) 2. Information describing each building block is entered into SimQuick tables in the form of statistical distributions 3. Statistics are collected by SimQuick and summarized 4. Change the percentage of simulated customers selected for the second inspection to 15% and then to 20% and rerun the model 5. Rerun these simulations with one more workstation and see if its effect on the waiting time for the second inspection Decision Areas for Management Possible changes to solve the problem: 1. Arrival rates  advertising, promotions, differential pricing

2. Number of facilities  increase facilities 3. Number of phases  allocate service tasks to sequential phases 4. Number of servers per facility 5. Server efficiency  adjust capital-to-labor ratio, improved work methods, incentive programs 6. Priority rule 7. Line arrangement...