Reference no: EM132431958
Define the goals of the model, the hypotheses to be used and the conceptual model. Finally implement the model with SIMIO and discuss the results.
System description: Workshop
A workshop that works 14 hours per day, 6 days per week, receives orders for manufacturing 1 unit of a product. Times between consecutive orders follow an exponential distribution of 3 minutes. There are the following 4 types of orders with an uniform probability: 1) to manufacture 1 unit of product A, 2) to manufacture 1 unit of product B, 3) to manufacture 1 unit of product C), and 4) to manufacture 1 unit of product D.
The workshop has 3 sections that we call Section 1 (S1), Section 2 (S2) and Section 3 (S3). In each section, there is a buffer (queue) with a capacity of 10 units (same capacity in the all sections).
Each type of product requires a different flow between the sections, according to Table 1.
|
Product A
|
S3 » S1 » S2 » S1
|
|
Product B
|
S1 » S2 »S3 »S1 »S2
|
|
Product C
|
S2 » S1 » S2 » S3 » S1
|
|
Product D
|
S3 » S1 » S3
|
Table 1. Flow of the products
The manufacturing time on a section (each time that a unit is processed in that section) does not depend on the type of product and are the following ones. In Section 1, the time is an exponential distribution of 1.7 minutes. In Section 2, the time is a truncated normal distribution of 2.4 minutes of mean, a deviation of 0.2 minutes and a lower limit of 1.5 minutes. In Section 3, the time is a uniform distribution between 1.5 and 1.8 minutes.
Moreover, a transport time of the units between sections has to be taken into account. The velocity of the transport is 0.8 m/s and the distances between sections (in m) is given in Table 2.
Table 2. Distances between sections
At present, the workshop can improve technologically one (and only one) section in order to reduce 0.4 minutes the mean production time of the improved section. Which section should be improved?
Answer the following questions:
Question 1. Propose different criteria to decide which section should be improved.
Question 2. Develop a conceptual model of the proposed system and define all hypotheses and simplifications that you use.
Question 3. Use SIMIO to code the model of the system and prepare an experiment.
Question 4. Which section should be improved? Analyse the obtained results and justify your answer.
Question 5. What validation techniques can be applied to assure that the conclusions are correct?