Answered: A.What is the service rate in jobs per…

A.What is the service rate in jobs per hour for each design? b. For the service rates in part (a), what design appears to provide the best oR fastest service rate?

Practical Management Science

6th Edition

ISBN:9781337406659

Author:WINSTON, Wayne L.

Publisher:WINSTON, Wayne L.

Chapter12: Queueing Models

Section12.5: Analytic Steady-state Queueing Models

Problem 9P

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no handwritten solution Question The management of a busy petrol station is concerned that customers are being lost because of long waiting times sometimes required at their petrol pump. Over a two weeks period a careful study has been taken of the arrival of cars and the length of time taken to serve customers at the petrol station. The tables below show the arrival rates and the service time distribution: Inter arrival time (minutes) Inter arrival time Midpoint Percentage of customers Cumulative frequency Random number 0 - <2 1 60 60 00 - 59 2 - <4 3 25 85 60 - 84 4 - <6 5 10 95 85 - 94 6 - <8 7 5 100 95 - 99 Service time (minutes) Inter arrival time Midpoint Percentage of customers Cumulative frequency Random number 0 - <4 2 20 20 00 – 19 4 - <6 5 30 50 20 – 49 6 - <8 7 20 70 50 - 69 8 - <10 9 15 85 70 – 84…
obs arrive at Loaf Machine Shop. Assume the arrival rate is five jobs per hour. Service times (in minutes per job) do not follow the exponential probability distribution. Two proposed designs for Loaf Machine Shop operation are shown. Design Mean Standard Deviation A 6.0 3.0 B 6.25 0.6 What are the standard deviations of the service times in hours? Which design provides the best operating characteristics? Why?
Q2. Customers visit an astrologer at a rate of 4/hour (Poisson) and take and average of 12 minutes (Exponential). Compute the probability that: a) There are three or less people in the system b) There are 5 or more people in the system c) The astrologer is free
The common measures of a queuing system's performance include: O probability that the service facility will be idle, average queue length, and probability that the waiting time will exceed a specified duration. average time each customer spends in the system, probability that the service system will be idle, and average time each customer spends in the queue. average queue length, maximum time a customer may spend in the queue, and the utilization factor for the system. average time each customer spends in the system, maximum queue length, and probability of a specific number of customers in the system. maximum queue length, maximum time a customer may spend in the queue, and average queue length.
B. Draw and explain the flow charts of the Arrival Event and Service Completion Event.
The BPD has three tellers to provide service. Each teller, on average, serves one customer in three minutes per customer, the latter arriving 50 every hour. Due to complaints received, an evaluation of the system has been requested:(a) Give the average utilization of the service system with the three tellers.b) What is the probability of arriving at the bank with no one there?c) What is the average number of customers waiting in line?d) On average how long does a customer wait in line to be served?e) On average how many customers would be served at a teller and waiting in line?
5.) Consider an M/M/2 system with an arrival rate of 9 per minute and a service rate of 8 per minute. What is the average number of customers in the system? Take your answer to three decimal places. Omit the units.
1. What is the outcome when a bottleneck resource is augmented with more capacity? 2. Which of the following statements are true? a) Installed capacity in service systems are always based on peak demand b) Service systems designed to handle average capacity will be more effective c) Improving effectiveness of a service will require greater investment of capacity d) None of the above 3. The arrival rate at the second server in a two stage serial queuing system is a. Service rate of server 1 b. Same as arrival rate at server 1 c. Minimum of service rate and arrival rate at server 1 d. Cannot be determined In a worker paced assembly line, consider a situation where the daily requirement has suddenly increased. Which of the following statements will be true? 4. In a worker paced assembly line, consider a situation where the daily requirement has suddenly increased. Which of the following statements will be true? a) The required cycle time will also increase proportionally b) The…
Using the Queuing Theory principles, a) List Lq, and Wq for all of the stations in a table b) Determine the performance measure (L,W) of the system. 0.25 S2 S4 0.6 Hz=15 H4=13 2=15 S1 S5 H=20 0.9 Hs=15 S3 H3=8
The state operates a weigh station for trucks traveling on the highway. Every truck must pull off the highway, enter the weigh station, and undergo state inspection procedures before counting on. Trucks arrive at this station at a poisson rate of seven per hour. The time to inspect/weigh a truck varies, having an exponential probability density with a mean of 7 minutes.A. How many trucks are detained at the station on the average? B. How long can a truck expect to be detained?C. How many trucks are lined up in front of the station on the average?D. How long on the average does a truck driver have to wait in line for the truck to beinspected?