simulation
Wvwilp
Arenareport.docxRestaurant Analysis based on Arena Model
Abstract
This report includes a simulation model for fast food restaurant and sit down restaurant that built using Arena simulation software. The construction and specific settings of the model will be described in details. The simulation was built by using blocks from basic process, advanced process and advanced transfer and run in 30 replications with the length of 12 hours. We also proposed some performance measures to be evaluated for our case study, which is the net revenue, net cost and total profit. The results will be analyzed to indicate which case will get more profit.
Table of Contents
1. INTRODUCTION
2. SYSTEM DESCRIPTION
2.1 RESOURCES
2.2 SET
2.3 SCHEDULE
3. RESULTS AND ANALYSIS
3.1 ORIGINAL MODEL
3.2 REDUCE TWO WAITERS
3.2 REDUCE THREE WAITERS
4. CONCLUSION
5. REFERENCES
1. Introduction
Simulation is the imitation of the operation of a real-world process or system over time [1]. Simulation A descriptive technique that enables a decision maker to evaluate the behavior of a model under various conditions [2]. The act of simulating something first requires that a model be developed; this model represents the key characteristics or behaviors of the selected physical or abstract system or process [3]. The model represents the system itself, whereas the simulation represents the operation of the system over time [4]. Simulation is used in many contexts, such as simulation of technology for performance optimization, safety engineering, testing, training, education, and video games [1]. Training simulators include flight simulators for training aircraft pilots to provide them with a lifelike experience [5]. Simulation is also used with scientific modeling of natural systems or human systems to gain insight into their functioning. Simulation can be used to show the eventual real effects of alternative conditions and courses of action [6]. Simulation is also used when the real system cannot be engaged, because it may not be accessible, or it may be dangerous or unacceptable to engage, or it is being designed but not yet built, or it may simply not exist [6]. A computer simulation (or "sim") is an attempt to model a real-life or hypothetical situation on a computer so that it can be studied to see how the system works [1]. By changing variables in the simulation, predictions may be made about the behavior of the system. It is a tool to virtually investigate the behavior of the system under study. Simulation can be defined as a series of “what-if” type experiments are carried out on the simulation model. Therefore, simulation has a wide range of applications [6]. Here we want to use the simulation to study and analyze the fast food restaurant system and sit down restaurant system, especially the revenue, cost and profit of these two different systems. That will be useful for restaurant hosts to determine so many details of their restaurant, for example, how many waiters will be the best choice, how much salary for waiters will be appropriate and how many tables are good.
2. System description
The project includes two parts, one is the fast food restaurant model and another one is for the sit down restaurant system. For both systems, patrons has an exponential interarrival times with a mean of 6 minutes and arriving rate as 0.5 per minute. The route and station block will be applied to achieve the process of waiting and check in. For the sit down system shown as figure 1, there are three processes. The first one represents the check in process that uses service time as TRI (0.1, 0.5, 1), the second one is dinning process which uses service as TRI (45, 60, 120) and the third one is check out process using the Constant (5). Number of sit down customers will be recorded by a record block.
Figure 1: Sit Down Restaurant model
The model of fast food restaurant consists of the same input, decide block to order the food, three process blocks to represent different time spent on choosing food and corresponding record block to record the customer numbers going through. There are three popular food choices in fast food restaurant which are chicken, beef and fish. There are 35% customers will choose chicken, 35% customers will pick beef and rest of them will choose fish. Different food need different time to be prepared, chicken process uses service time as TRI (3.1, 5.2, 6.2), beef process uses service time as TRI (3.2, 4.6, 5.8) and fish uses the longest service time as TRI (6.3, 7.5, 10.0). The whole fast food restaurant system is shown as figure 2.
Figure 2: Fast food Restaurant model
2.1 Resources
Resources details will be described in that section. Firstly, sit down restaurant needs a hostess to host the check in table and she is able to earn 9 dollars per hour. Also we have assigned 5 waiters for sit down restaurant and one cashier to take care of the checkout process. All staff in that restaurant could earn 9 dollars per hour. However, fast food restaurant just needs three staff to take care of ordering food and checking out process. They can just earn 8 dollars per hour because of they don’t have tips in the system. The whole resources table is shown as figure 3.
Figure 4: Resources table
2.2 Set
The dining process needs a set to serve customers which includes 5 staff who are Carl, Bryan, Melanie, Lindsey and Jerry as shown in figure 5.
Figure 5: Set and set members
2.3 Schedule
The schedule will be applied to every staff. We assume they work 12 hours per day and the two breakouts will begin after 4 hours and 8 hours working. Everyone is taking the 30 minutes break time one by one to have lunch and do whatever they want. The first taking break time staff’s schedule is added like the following figure 6.
Figure 6: Schedule of Carl
3. Results and analysis
The model will be simulated and results will be analyzed in purpose of determining which case can earn more money. Also we will adjust variables like reducing number of waiters to see if the sit down restaurant can do better or the system will crash without enough help. The model was setup for a 12 hour business day, replicated 30 days to show one month’s average data. Firstly, we record the original model’s results, then reduce number of staff for two times to see if the system works fine.
3.1 Original model
Figure 7: Order number of different food
Figure 7 shows that fast food restaurant sold Beef 85, Chicken 87, Fish 71 and 214 in total. Sit down restaurant sold 209 plates in total. They sold almost the same quantity of meals but the profit of each meals for sit down restaurant would be bigger than those in fast food restaurant. Figure 8 shows the profit of each meals for each case, also the cost for each case. The total profit per day of each case would be calculated and compared. It’s obvious that sit down restaurant is able to earn more than fast food restaurant if each restaurant has the same quantity of customers.
Figure 8: Results of overall sales
3.2 Reduce two waiters
In 3.1, we found out that each waiter in sit down restaurant doesn’t have a high utilization percent so that it’s reasonable to reduce some of them to earn more in the future. The following picture shows the average utilization for each one after reducing 2 waiters. The rest of three waiters both have been used for 48% per day.
Figure 9: Utilization of 3 waiters
As a result of reducing two waiters, the total profit per day increases to $1,103 from 207 meals served. The original one just has $923 per day.
3.3 Reduce 3 waiters
Finally, we reduce three waiters to see if two waiters could handle the all customers per day. Even though waiter has their break, two waiters for a sit down restaurant is really insufficient. Each waiter has a utilization percent as 70% shown in figure 10.
Figure 10: Utilization of 2 waiters
In that case, the sit down restaurant could earn the most profit per day as $1,227. But that would bring these two waiters too much pressure and dissatisfied.
4. Conclusion
Based off averages of a month’s analysis, the sit down restaurant makes on average more money. It would be most beneficial to expand the restaurant to an all Sit Down type and possibly with reduced staff for max profit. Model was modified to run 10 replicates to indicate that the overall time the customers spend in the Sit Down Restaurant is statistically significant with 95% confidence. Done to prove that reduction in staff in terms of overall time is statistically significant and verified with 95% confidence. There is no significant Difference in customer Time in system. The whole demonstrate process has been shown in the figure 11.
Figure 10: Analysis for total customer time in system
Based off a paired-t analysis of customer time in the system as to not cause dis-satisfaction based off of reduced staff, the data appears to shown little resultant effect on time on the 95% confidence level. Owner will then make calculated decision to choose to open a Sit Down restaurant with 2 wait-staff and hostess and make on average about $1,227.20/day Net after expenses.
5. References
[1] Nelson, Barry L., John S. Carson, and Jerry Banks. Discrete event system simulation. Prentice hall, 2001.
[2] Stevenson, William J., and Mehran Hojati. Operations management. Vol. 8. Boston: McGraw-Hill/Irwin, 2007.
[3] Gallagher, Anthony G., and Gerald C. O’Sullivan. "Simulations for Procedural Training." Fundamentals of Surgical Simulation. Springer London, 2012. 39-66.
[4] Levine, Adam I., et al. "Healthcare Simulation: From “Best Secret” to “Best Practice”." The Comprehensive Textbook of Healthcare Simulation. Springer New York, 2013. 3-4.
[5] Kelton, W.D., Sadowski, R.P., and Swets, N.B. Simulation with Arena Fifth Edition. McGraw Hill. 2010.
[6] Law, A., and Kelton, D. Simulation Modeling and Analysis Fourth Edition. McGraw-Hill. 2007.
