Exam 13: Simulation Modeling

Table 13-2 A new young mother has opened a cloth diaper service.She is interested in simulating the number of diapers required for a one-year-old.She hopes to use this data to show the cost effectiveness of cloth diapers.The table below shows the number of diapers demanded daily and the probabilities associated with each level of demand. -According to Table 13-2,if the random number 40 were generated for a particular day,what would the simulated demand be for that day?

Table 13-4 A pawn shop in Arlington,Texas,has a drive-through window to better serve customers.The following tables provide information about the time between arrivals and the service times required at the window on a particularly busy day of the week.All times are in minutes. The first random number generated for arrivals is used to tell when the first customer arrives after opening. -According to Table 13-4,the time between successive arrivals is 1,2,3,or 4 minutes.The store opens at 8:00 a.m. ,and random numbers are used to generate arrivals and service times.The first two random numbers for arrivals are 95 and 08.The first two random numbers for service times are 92 and 18.At what time does the second customer finish transacting business?

Table 13-5 -According to Table 13-5,which presents a summary of the Monte Carlo output from a simulation of 200 runs,there are 5 possible values for the variable of concern.If random numbers between 01 and 100 are used to generate values,then a random draw of 72 would produce a variable value of

Simulation models are useful for economic order quantity problems with probabilistic demand and lead time.

Simulation of a business or process is generally performed by building a mathematical model to represent the process or system.

The four disadvantages of simulation are cost,its trial-and-error nature,time compression,and uniqueness.

The process of determining that the computer model is internally consistent and following the logic of the conceptual model is called

Simulation models are limited to using standard probability distributions such as Poisson,exponential,normal,etc.

Table 13-3 A pharmacy is considering hiring another pharmacist to better serve customers.To help analyze this situation,records are kept to determine how many customers will arrive in any 10-minute interval.Based on 100 ten-minute intervals,the following probability distribution has been developed and random numbers assigned to each event. -According to Table 13-3,the number of arrivals in any 10-minute period is between 6 and 10,inclusive.Suppose the next three random numbers were 18,89,and 67,and these were used to simulate arrivals in the next three 10-minute intervals.How many customers would have arrived during this 30-minute time period?

Simulation can use any probability distribution that the user defines;it does not require standard distributions.

What are the seven steps of simulation?

What is the probability of selecting any random number from a two digit table?

A flow diagram is helpful in the logical coding procedures for programming a simulation process.

What is the difference between verification and validation?

Table 13-2 A new young mother has opened a cloth diaper service.She is interested in simulating the number of diapers required for a one-year-old.She hopes to use this data to show the cost effectiveness of cloth diapers.The table below shows the number of diapers demanded daily and the probabilities associated with each level of demand. -According to Table 13-2,if the random number 96 were generated for a particular day,what would the simulated demand be for that day?

Operational gaming involves a single player competing with the computer simulated game.

Which of the following scenarios would require simulation for a queuing model?

Average daily sales of a product are 8 units.The actual number of sales each day is either 7,8,or 9,with probabilities 0.3,0.4,and 0.3,respectively.The lead time for delivery of this averages 4 days,although the time may be 3,4,or 5 days,with probabilities 0.2,0.6,and 0.2.The company plans to place an order when the inventory level drops to 32 units (based on the average demand and average lead time).The following random numbers have been generated: 60,87,46,63 (set 1)and 52,78,13,06,99,98,80,09,67,89,45 (set 2).Use set 1 of these to generate lead times and use set 2 to simulate daily demand.Simulate 2 ordering periods with this and determine how often the company runs out of stock before the shipment arrives.Assume 32 units on-hand and an order was just placed.

The advantage of simulation over queuing or waiting line models is that simulation allows us to relax our assumptions regarding arrival and service distributions.

The probability of selecting any random number in a two digit table is 1/100.