Systems Modelling and Simulation

Systems Modelling and Simulation

Learning Outcomes

1.  Critically evaluate and implement principles of systems approach and analysis.

2.  Describe, critically evaluate and appropriately apply manufacturing concepts to real world industrial systems and to design, plan and solve arising problems that day-to-day management of such systems encounter.

3.  Develop the required skills for modelling, simulating and critically analysing performance of deterministic and stochastic systems.

4.  Acquire the skills to recognise the elements and rules governing supply chains/logistics and reverse logistics for

better management and engineering of these systems.

5.  Apply key tools and techniques for planning and critically evaluating the design of enterprise systems

6.  Modelling of interactions and negotiations between components of enterprise systems

7.  Demonstrate integrated modelling of key processes within manufacturing systems

8.  Use simulation and optimisation techniques to identify improvements for Enterprise integration

9.  Preparation of written reports

10.Critically evaluate a range of complex scenarios and make informed decisions.

11.Exercise a high level of initiative and personal responsibility

Assessment Overview

-     The final assessment for this module is a  final Project and Report 100% (3,000 Words) with 3 parts to analyse.

-     Please ensure to submit all 3 parts in  one final report for your submission on WISEflow.

-     Please take note of the Special instructions below and the Key Components and Task outline for the 3 parts of this assessment.

Special Instructions

Every year the individual assignment for the Systems Modelling and Simulation module has a different theme. For example, in the previous years the assignments had manufacturing, banking services, airports, and logistics themes. This year our assignment is about Healthcare. All this variation allows you to appreciate how this fundamental subject can be applied to different problems which fundamentally have similar performance indicators. Enjoy this year’s assignment!

A clinical centre in a war torn country in a remote area receives patients with various conditions. The clinic works 24 hours a day and admits two types of patients.

Patient Type 1 (Low Priority): These are type of patients that are of low priority and they are normally treated by either the Clinical Nurses (CN) or the General Practitioners (GP). These patients arrive at the hospital with a rate Expo (20) min. They are seen by the admission officer, register and are sent to the Triage station. The registration follows POIS distribution with the following parameter (8) minutes. At the Triage station if a CN is available they are assigned to a nurse and only at special occasions if all the CNs are busy and if a GP is available the patient will be seen by the GP for assessment. If there are no Triage staffs available, the patients wait in the waiting area. This area has maximum capacity of 20 people (i.e. if the number in the queue behind the Triage is more than 20 the patient leaves the hospital). Report on the record of number of patients who leave the medical centre without being attended to. Patients that arrive during the break of the Admissions officer leave the system (record the number and report on this number of patients leaving due to admissions being closed)

The Triage processes consist of Patient Assessment, the assessment process follows a Triangular distribution with the following parameters (8, 12, 15) minutes. After the assessment process 85% of the patients are diagnosed, given medication by the Triage staff and leave the clinic. The remaining 15% have further complications that require further consultation with a GP in the Triage for further assessment. The processing time for these patients is Uniform (7, 10) minutes. 30% of these patients who have been diagnosed by the GPs need to be admitted to a bed for admission of drip medicine or monitoring and the rest of patients are discharged and leave the system. The admitted patients normally occupy the beds following a Triangular Distribution (10, 20, 35) hours.

All discharge processes require the chief nurse and one of the GPs (the less busy one) to assess the patient. This process takes a Weibull distribution (14, 18) minutes. The patient is provided with the necessary medication and leaves the system. There are no admissions after 6:00pm.

Patient Type 2 (High Priority): Are patients with severe illnesses or wounds they are at a rate of Expo (220) minutes and take priority over the low priority patients. The high priority patient does not go through the admission process. These patients are assessed at the Triage by any available CN or GP and admitted to operation room (hint: this type of patients has higher priority to type 1 in the triage). There are 2 surgeons available and they conduct surgery from 9:00am to 6:00pm. Each surgery requires a surgeon, one of the 2 available Operation Rooms and one OR Nurse. The operation follows an Erlang Distribution with the following Distribution parameters (1, 2.3) hours. The queue behind the operation has maximum capacity of 10. Upon completion of the operation the patient is admitted to a bed in the Ward. The excess patients from queueing for Operation (more than 10 in the queue) are sent for transfer by the ambulance to the hospital.

There are a total number of 5 beds in the Clinic Ward and is shared between all patients that are admitted to the hospital (Low and High Priority Alike). The capacity of queue behind the ward is 3. If all beds are occupied or there is not enough space behind the operation rooms, the patient is transferred to a faraway hospital using the 2 available ambulances (Each ambulance is used half of the time). If neither beds nor ambulance is available the patient will lose his/her life.

The Operation Room relies on a power Generator that breaks down (making total operating room unusable) following a Poisson

Distribution of 3 times a month with it taking Normal Distribution time of (2, 0.5) hours to fix.

The operation room has also a number of machines that need to be working during the operation. They are:

  Machines  Number Available  Mean time between failures (days), Rule  Out of Service Time (min)
ECG3Expo(10), Pre-emptTriangular(30, 45, 60)
Resuscitation2Expo(15), Pre-emptTriangular(120, 150,180)
Defibrillator2Expo(5), Pre-emptTriangular (10, 30, 60)

Patients can only be discharged between 8:00am-7:00pm. Any patient missing the 7:00pm Discharge would remain in the clinic – occupying the bed until the following day to be discharged.

There are 2 Ward Nurses (WN) during the day and 1 at night shifts. The WN are assigned to all beds in ward and they monitor patients, one has to be present at any time. In the day each nurse has to go to a break at least every 6 hours. When both nurses are available they agree to take responsibility for one area of the Ward which is equally divided between them. The Clinical staff and admissions staff follow rotating shifts with the following schedules:

  Type  Number  Schedule  Rule
Admission & OR Nurse  1 &   1  8:00-6:00pm – Lunch Break 12:00-12:30, Afternoon Break 3:00-3:30  Wait
CN28:00-7:00pm – Lunch break one nurse at a time can be anytime between 12:00-2:00pm. Duration of break 30 minutes. Afternoon break between 3:00- 5:00pm only one can go on a break at each time.Ignore
  WN  2 Day  Day shift 8:00-8:00pm - Lunch break one nurse at a time can be anytime between 12:00-2:00pm.  Wait
  Duration of break 30 minutes. Afternoon break between 3:00-5:00pm only one can go on a break at each time. Night Shift 8:00pm-8:00am the nurse will eat and drink whilst on watch (no breaks). 
  Chief Nurse  1  8:00-7:00pm 12:00-1:00pm lunch break and hour 3:30-4:30 tea break in the afternoon  Ignore
  GP  2  8:00-7:00pm – Lunch break one nurse at a time can be anytime between 12:00-2:00pm. Duration of break 30 minutes. Afternoon break between 3:00- 5:00pm only one can go on a break at each time.  Pre-empt
  Surgeons  2  9:00am-6:00pm – The surgeons are required to take 4, 30 minute breaks during their shift. They make sure that the surgeries are completed within the scheduled hours and make a round of the Ward after 6:00pm which normally takes 1 hour.  Wait
  Ambulance  2  Available all the time. The round trip from the clinic to the hospital and back is 300 miles. Average speed is 65 per hour.  Wait

Key Components and Task:

Part 1 (35%):

Using Arena - Warm-up Period = 12 hours, simulate the system 30 days. The number of Replications should be at least 5 (no initialisation of stats). Make sure you animate the system with a reasonable layout:

Using the results of the simulation answer and explain the following questions:

1.              What is the Total Number of patients by type that are treated in the clinic?

2.              What is the average waiting time for each type of patient?

3.              What is the average utilisation of all staff?

4.              What is the average time spent in the system by patient type?

5.              What is the average WIP by patient type?

6.              Identify the bottleneck of the system, if any exists, and explain why you think that they are bottlenecks of the system.

7.              How many patients are lost due to full queues and lack of resources (specify by type)? Explain the implications of such loss.

8.              What is the mortality rate?

9.     What happens to the mortality rate if an assumption is added that patients who wait in excess of 1 hour in the queue for transfer to hospital lose their lives?

10.            What is the ideal number in the queue behind the operation room or transfer to hospital that minimises mortality rate?

NOTE: Model the ambulances in the Ward as transporters.

Part 2 (30%):

The clinical staff believes that the loss of patients due to overstretched resources is not acceptable. Using the results from the simulation of the actual system, suggest what sorts of changes are required both in staff and equipment that could improve the quality of service and reduce losses of lives:

11.            Reduce the number of lost patients due to long queues?

12.            Better utilisation of the resources?

13.            What sort of support should the clinical staff require to reduce casualties?

14.            Reduce Mortality Rate

Part 3 (35%):

Assuming that the clinic has been promised with further funding, how would you recommend the funding to be spent? How would you priorities the allocation of resources. How many more beds, how many more staff with various specialities (Admission, Clinical and Ambulance)? How would you improve the availability of equipment with this fund? What is the distance between the current system and an ideal system in which key performance factors of the system are at optimal situation with balanced utilisation of resources and minimum casualty? Simulate the new system and extract what exactly is required to reach the optimum level of resources.

Use your common sense in assessing the cost of staff, beds, equipment, ambulance, generator, etc. You may even use a simple financial analysis by allocating arbitrary but realistic cost against each resource.

Helpful instructions / resources:

-       Please enclose a print out of the Arena’s final Summary Report (*.out) for each part of the assignment as an appendix to your report. The summary report is automatically generated by Arena in the same directory that you run and compile your model.

-       Part of the allocated mark for each part is for intuitive modelling approach, design, animation, and presentation of the simulation models and the report. The value and the results need to be interpreted and explained.

-      For assistance with Arena software, please refer to Unit 1 – Lesson 4 of 6

Ensure that you follow the assignment guidelines for submission which is available on:

http://people.brunel.ac.uk/~emstaam/

-       Click on Teaching Systems Modelling and Simulation →   Assignment and Project submission guidelines

Submission deadline: 11:59 am UK time Thursday 2nd September, 2021

Submission Method: via the WISEflow platform - (additional material can be added in the Appendix

Section) **Please ensure to give yourself enough time to submit before the deadline.

Late submission rules: as per the University’s policy

Relevant Programme regulation: Senate Regulations 3

Provision of formative assessment: Not applicable.

Marking criteria: attached (Annex I)

** All submissions will be electronically checked for plagiarism. **

It is the student’s responsibility to ensure they are aware of polices and practice on good academic practice and plagiarism. You can find more information about this in the Senate Regulations: Senate-Regulation-6-

2020-07-01.pdf (brunel.ac.uk).

Use your student ids for anonymity (i.e. no student names on the assignment itself).

Annex I: Brunel University Generic Masters-level Grade Descriptors

These generic grade descriptors are intended to be used as a tool throughout the assessment process (in assessment design, marking/grading, moderation, feedback and appraisal) for any assessment set at Masters Level in the University. They are designed to show no disciplinary bias and are not intended to act as surrogate award or award classification descriptors. The grade descriptors should be read in conjunction with the learning outcomes associated with the assessment.

Grade A++

Work of exceptionally high quality, commensurate with publication in a highly esteemed peer-reviewed journal. Clearly emonstrates a sophisticated, critical and thorough understanding of the topic. Provides clear evidence of originality and clearly demonstrates the ability to develop an independent, highly systematic and logical or insightful argument or evaluation. Demonstrates exceptional ability in the appropriate use of the relevant literature, theory, methodologies, practices, tools, etc., to analyse and synthesise at Masters Level. Shows exceptional clarity, focus and cogency in communication.

Grade Band A (A+, A, A-)

Clearly demonstrates a sophisticated, critical and thorough understanding of the topic. Provides evidence of originality of thought and clearly demonstrates the ability to develop an independent, highly systematic and logical or insightful argument or evaluation. Demonstrates excellence in the appropriate use of the relevant literature, theory, methodologies, practices, tools, etc., to analyse and synthesise at Masters Level. Shows excellent clarity, focus and cogency in communication.

Grade Band B (B+, B, B-)

Clearly demonstrates a well-developed, critical and comprehensive understanding of the topic. Clearly demonstrates the ability to develop an independent, systematic and logical or insightful argument or evaluation. Demonstrates a high degree of competence in the appropriate use of the relevant literature, theory, methodologies, practices, tools, etc., to analyse and synthesise at Masters Level. Shows a high level of clarity, focus and cogency in communication.

Grade Band C (C+, C, C-)

Demonstrates a critical and substantial understanding of the topic. Demonstrates the ability to develop an independent, systematic and logical or insightful argument or evaluation. Demonstrates a significant degree of competence in the appropriate use of the relevant literature, theory, methodologies, practices, tools, etc., to analyse and synthesise at Masters Level. Provides evidence of clarity, focus and cogency in communication.

Grade Band D (D+, D, D-)

Provides evidence of some critical understanding of the topic. Demonstrates some ability to develop a structured argument or evaluation. Demonstrates an acceptable degree of competence in the appropriate use of the relevant literature, theory, methodologies, practices, tools, etc., to analyse and synthesise, but not at Masters Level. Provides evidence of effective communication.

Grade Band E (E+, E, E-)

Work that demonstrates significant weaknesses, but which provides strong evidence that Grade D is within the reach of the student.

Grade F

Work that is unacceptable.

[Available from intranet: https://intra.brunel.ac.uk/s/QSO/_layouts/15/WopiFrame.aspx?sourcedoc=/s/QSO/Handbook%20Text/Postgraduate%20grade%20descriptors. doc&action=default&DefaultItemOpen=1