The purpose of this assessment is to create a fully functional simulation of a more complex system. Building simulations is one of the key objectives of this course. You will need to be able to do this in an industry or government job working in decision sciences. Building a simulation is also the best way to absorb and gain a deep understanding of the ideas and topics that are discussed in this course. Even if you are just managing simulations projects, you should have some experience in creating the simulation itself.
This is quite a large and difficult task, but the assessment will provide considerable structure.
This Task addresses the following Course Learning Outcomes:
1. Communicate how randomness and controlled variation can be used to model complex systems in a range of application domains such as industry, health, and transportation.
Copyright By PowCoder代写 加微信 powcoder
2. Create a model of a real-world problem specified in words and implement it as a discrete-event simulation.
3. Validateresultsfromadiscrete-eventsimulation.
You will be simulating a factory production line that constructs lawnmowers to order.
The construction process involves a small number of main steps. Each is a series of tasks, but you will only model the main bottleneck task. Presume that the mower is built from a series of prefabricated parts (the engine, the blades, the frame and so on).
The bottleneck in this process is that, in this factory, there is only one machine that can properly fasten the blades to the motor as they have to be attached securely to make them safe.
Unfortunately, the blade-fitting machine is old and breaks down sometimes. If this happens, it is out of service while it is being repaired, and any orders will have to wait.
Assumptions
You should assume the following:
• Orders for new lawnmowers are processed in a FIFO manner and there can be an unlimited number waiting.
• Times: all times are independent and
o the inter-arrival times between orders are independent and exponential
with a mean of one hour.
o thetimetoconstructalawnmowerfrompartsisdeterministicwitha time of 45 minutes.
o the time between breakdowns of the blade-fitting machine is exponential with a mean of two days as measured from the last time it was repaired.
o the time to fix the machine when it breaks is exponential with a mean time of three hours.
• There is an unlimited number of parts available to construct new lawnmowers.
• If the blade-fitting machine breaks down while constructing a lawnmower, the work already completed on that lawnmower is interrupted but ‘saved’. That is, the total time to complete the lawnmower is the construction time, plus any repair times that interrupt construction (it is technically possible that more than one breakdown could occur during the same lawnmower build).
The factory owner wants to know how to improve their factory, the most obvious change would be to buy a replacement machine to attach the blades. The new machine would break down less often, so the mean time between breakdowns will be
Page 2 of 25
longer. They would like to assess the business case for such a purchase, i.e., what would the reduction in waiting time for orders be, and what percentage of orders would be interrupted with the new machine. Therefore, the questions they would like to answer are:
• How much production time is lost to repairs?
• How many lawnmowers have their construction interrupted due to a
breakdown and repair?
• How long do orders wait in this system before being completed, and how much
would this be improved if the time between breakdowns was extended?
This assessment is scaffolded into three parts:
• Part 1: Conceptual model (Module 2)
• Part 2: Functionality (Module 3)
• Part 3: Programming (Module 4)
The details of each part are outlined in Appendix 1–3 of this brief, and can also be found at the end of Module 2, Module 3 and Module 4 of this course.
Requirements
You will be assessed on three components of this work:
• Component 1: Conceptual model—your ability to formulate the model.
• Component 2: Functionality—your ability to write code to create a simulation,
and ensure the sub-components of it work.
• Component 3: Programming style—your ability to write your program
according to the specifications and general style guidelines for good code. You are required to submit:
• a PDF document showing your schematic, state diagram, flow chart and any other documentation you created.
• two .jl files with your code for implementing the discrete-event simulation.
• a pair of data files (an entities and a state file) produced from your simulation
with seed=1 and where the simulation was stopped at time T=1000.0.
Consult the assessment rubric when preparing your submission. Questions can be posted to the relevant assessment Discussion Board.
Page 3 of 25
Grading Criteria
This assessment is worth 40% of your overall grade. Refer to the attached rubric for detailed information on the grading criteria for this assessment.
Page 4 of 25
Component 1: Conceptual Model
Draw a schematic of the system
Points: 2.0 Name: Full points
Points: 1.0
Name: Partial points
Points: 0.0 Name: No points
Your schematic correctly shows the standard queue components and the breakdown-repair cycle in some way.
You have correctly shown either the standard queue components or the breakdown-repair cycle.
Assessment requirements for this step have not been met.
Describe the state(s) of the system
Points: 2.0 Name: Full points
You have correctly described the state(s) of the system.
Points: 1.0
Name: Partial points
Points: 0.0 Name: No points
You have partially described the state(s) of the system.
Assessment requirements for this step have not been met.
Points: 1.0 Name: Full points
Points: 0.0 Name: No points
Task 3 1 pt Determine the
entities in the system
in relation to the state You have correctly determined the entities in the system. Assessment requirements for this step have not been met.
Page 5 of 25
List the types of events in your model
• describe how each event
changes the state of the system
• describe the new events that may be created
as a result of this event
Draw a flow chart illustrating your simulation structure
Points: 1.0 Name: Full points
You have correctly listed the types of events in your model.
Points: 0.0 Name: No points
Assessment requirements for this step have not been met.
Points: 3.0 Name: Full points
Points: 2.0
Name: Partial points
Points: 1.0
Name: Partial points
Points: 0.0 Name: No points
Your flow chart: (i) is a valid flow chart for this model, (ii) does not have any dead ends (except for the intended termination step); and (iii) includes vacation (machine breakdowns).
You have successfully completed two of the following: (i) a valid flow chart, (ii) there are no dead ends (except for the termination step); and (iii) included vacation (machine breakdowns).
You have successfully completed one of the following: (i) correctly drawn a valid flow chart, (ii) there are no dead ends (except for the termination step); and (iii) included vacation (machine breakdowns).
Assessment requirements for this step have not been met.
Section total:
Component 2: Functionality
Refine your schematic of the system (see Component 1: Task 1 for marks)
Page 6 of 25
Points: 1.0 Name: Full points
Points: 0.0 Name: No points
Task 2 1 pt Draw a state-diagram
of the system
Your state diagram shows the correct state transitions. Assessment requirements for this step have not been met.
Write code to implement a discrete-event simulation of the system.
Output state file:
Initialisation
Points: 2.0 Name: Full points
Points: 1.0
Name: Partial points
Points: 0.0 Name: No points
Your initialisation creates a valid starting state with an arrival at time 0.0 and a breakdown at time 150.0.
You have done one of the following: (i) created a valid starting state with an arrival at time 0.0, and (ii) created a valid starting state with a breakdown at time 150.0.
Assessment requirements for this step have not been met.
Output state file:
run! Initialisation
Points: 1.0 Name: Full points
Points: 0.0 Name: No points
Your run! function can be called with the prescribed inputs and does not crash.
Assessment requirements for this step have not been met.
Output state file:
Random number generators
Points: 4.0 Name: Full points
Points: 3.0
Name: Partial points
Points: 2.0
Name: Partial points
Points: 1.0
Name: Partial points
Points: 0.0 Name: No points
Your random number generators create suitable random numbers for: (i) inter-arrival times, (ii) construction times, (iii) breakdown times, and (iv) repair times.
Your random number generators have created suitable random numbers for three of the following: (i) inter-arrival times, (ii) construction times, (iii) breakdown times, and (iv) repair times.
Your random number generators have created suitable random numbers for two of the following: (i) inter-arrival times, (ii) construction times, (iii) breakdown times, and (iv) repair times.
Your random number generators have created suitable random numbers for one of the following: (i) inter-arrival times, (ii) construction times, (iii) breakdown times, and (iv) repair times.
Assessment requirements for this step have not been met.
Page 7 of 25
Output state file:
CSV format and metadata
Points: 2.0 Name: Full points
Points: 1.0
Name: Partial points
Points: 0.0 Name: No points
Your output state file conforms to the correct CSV format and contains satisfactory metadata.
You have done one of the following: (i) created an output state file that conforms to the correct CSV format, (ii) created an output state file that contains satisfactory metadata.
Assessment requirements for this step have not been met.
Output state file:
Points: 1.0 Name: Full points
Points: 0.0 Name: No points
Your output state file contains states that are sequentially ordered in increasing time.
Assessment requirements for this step have not been met.
Points: 1.0 Name: Full points
Points: 0.0 Name: No points
Output state file: 1 pt Event IDs
Your output state file contains unique event IDs. Assessment requirements for this step have not been met.
Output state file:
Arrival and breakdown
Points: 2.0 Name: Full points
Points: 1.0
Name: Partial points
Points: 0.0 Name: No points
Your output state file contains an arrival at time 0.0 and breakdown time at 0.0.
You have done one of the following: (i) created an output state file that contains an arrival time at 0.0, and (ii) created an output state file that contains a breakdown time at 0.0.
Assessment requirements for this step have not been met.
Output state file:
Points: 1.0 Name: Full points
Points: 0.0 Name: No points
Your output state file shows that the queue grows during the breakdown.
Assessment requirements for this step have not been met.
Page 8 of 25
Output state file:
Points: 1.0 Name: Full points
Points: 0.0 Name: No points
Your output state file shows that the event list always has 1 or 2 events in it.
Assessment requirements for this step have not been met.
Output state file:
Machine status
Points: 1.0 Name: Full points
Points: 0.0 Name: No points
Your output state file shows that the machine status is 0 normally and 1 after the start of a breakdown up until a repair.
Assessment requirements for this step have not been met.
Output entity file:
CSV format and metadata
Points: 2.0 Name: Full points
Points: 1.0
Name: Partial points
Points: 0.0 Name: No points
Your output entity file conforms to the correct CSV format and contains satisfactory metadata.
You have done one of the following: (i) created an output entity file that conforms to the correct CSV format, and (ii) created an output entity file that contains satisfactory metadata.
Assessment requirements for this step have not been met.
Output entity file:
Points: 1.0 Name: Full points
Points: 0.0 Name: No points
Your output entity file contains arrival times, start service times and completion times that are in increasing order.
Assessment requirements for this step have not been met.
Points: 1.0 Name: Full points
Points: 0.0 Name: No points
Output state file:
Your output entity file contains entities with unique IDs.
Assessment requirements for this step have not been met.
Section total:
Page 9 of 25
Component 3: Programming Style
Specification 1
File names, functions and data structures
Points: 1.0 Name: Full points
Points: 0.0 Name: No points
Assessment requirements for this step have not been met.
Your file names are correct, and the correct code is in the correct place (functions and data structures in particular).
Specification 2
Points: 1.0 Name: Full points
Points: 0.0 Name: No points
Your file names are correct, and the correct code is in the correct place (functions and data structures in particular).
Assessment requirements for this step have not been met.
Specification 3
Data structures
Points: 3.0 Name: Full points
Points: 2.0
Name: Partial points
Points: 1.0
Name: Partial points
Points: 0.0 Name: No points
You have three data structures declared in a valid manner with appropriate constructors.
You have two of the three data structures declared in a valid manner with appropriate constructors.
You have one of the three data structures declared in a valid manner with appropriate constructors.
Assessment requirements for this step have not been met.
Points: 1.0 Name: Full points
Points: 0.0 Name: No points
Specification 3 1 pt Event types
You have included concrete event types. Assessment requirements for this step have not been met.
Specification 4
Machine breakdowns
Points: 1.0 Name: Full points
Points: 0.0 Name: No points
You have included extra delays for machine breakdowns in the update function for breakdowns.
Assessment requirements for this step have not been met.
Page 10 of 25
Points: 1.0 Name: Full points
Points: 0.0 Name: No points
Specification 5
Update functions
Specification 6
Parameters
Specification 7
Constructor
Specification 7
Specification
Specification 8
run! function
Specification 9
Entities file
Specification 9
State file
You have included update functions for four types of events.
Your code has a data structure for passing parameters.
You have included a random number generator constructor.
You have included an initialise function matching specification.
You have included a run! function that runs the simulation.
Your program writes an entities file.
Your program writes a state file.
Assessment requirements for this step have not been met.
Assessment requirements for this step have not been met.
Assessment requirements for this step have not been met.
Assessment requirements for this step have not been met.
Assessment requirements for this step have not been met.
Assessment requirements for this step have not been met.
Assessment requirements for this step have not been met.
Points: 1.0 Name: Full points
Points: 0.0 Name: No points
Points: 1.0 Name: Full points
Points: 0.0 Name: No points
Points: 1.0 Name: Full points
Points: 0.0 Name: No points
Points: 1.0 Name: Full points
Points: 0.0 Name: No points
Points: 1.0 Name: Full points
Points: 0.0 Name: No points
Points: 1.0 Name: Full points
Points: 0.0 Name: No points
Page 11 of 25
Points: 1.0 Name: Full points
Points: 0.0 Name: No points
Specification 10
You have not included any global variables.
Assessment requirements for this step have not been met.
Specification 10
Variable names
Points: 1.0 Name: Full points
Points: 0.0 Name: No points
You have used meaningful variable names, with the exception of local variables with small scope.
Assessment requirements for this step have not been met.
Specification 10
Points: 2.0 Name: Full points
Points: 1.0
Name: Partial points
Points: 0.0 Name: No points
You have used comments efficiently and effectively.
You have partially used comments efficiently and effectively.
Assessment requirements for this step have not been met.
Specification 10
White space
Points: 1.0 Name: Full points
Points: 0.0 Name: No points
You have used correctly and consistently used indentation and space to separate important components and expressions.
Assessment requirements for this step have not been met.
Specification 10
Inefficient approaches
Points: 1.0 Name: Full points
Points: 0.0 Name: No points
You have used correctly and consistently used indentation and space to separate important components and expressions.
Assessment requirements for this step have not been met.
Section total:
Assessment total:
Page 12 of 25
Appendix 1
Part 1: Conceptual Model
In this part, you will consider the system model that you will be implementing.
The system
You will be simulating a factory production line that constructs lawnmowers to order.
The construction process involves a small number of main steps. Each is a series of tasks, but you will only model the main bottleneck task. You can presume that the mower is built from a series of prefabricated parts (the engine, the blades, the frame and so on).
The bottleneck in this process is that, in this factory, there is only one machine that can properly fasten the blades to the motor as they have to be attached securely to make them safe, so only one lawnmower can be made at once.
Unfortunately, the blade-fitting machine is old and breaks down sometimes. If this happens, it is out of service while it is being repaired, and any orders have to wait.
Assumptions
You should assume the following:
• Orders for new lawnmowers are processed in a FIFO manner and there can be an unlimited number waiting.
• Times: all times are independent and
o the inter-arrival times between orders are independent and exponential
with a mean of one hour
o thetimetoconstructalawnmowerfrompartsisdeterministicwitha time of 45 minutes
o the time between breakdowns of the blade-fitting machine is exponential with a mean of two days as measured from the last time it was repaired
o the time to fix the machine when it breaks is exponential with a mean of time three hours.
• There is an unlimited number of parts available to construct new lawnmowers.
• If the blade-fitting machine breaks down while constructing a lawnmower, the work already completed on that lawnmower is interrupted but ‘saved’. That is, the total time to complete the lawnmower is the construction time, plus any repair times that interrupt construction (it is technically possible that more
Page 13 of 25
than one breakdown could occur during the same lawnmower build).
The factory owner wants to know how to improve their factory, the most obvious change would be to buy a replacement machine to attach the blades. The new machine would break down less often, so the mean time between breakdowns will be longer. They would like to assess the business case for such a purchase, i.e., what would the reduction in waiting time for orders be, and what percentage of orders would be interrupted with the new machine. Therefore, the questions they would like to answer are:
程序代写 CS代考 加微信: powcoder QQ: 1823890830 Email: powcoder@163.com