首页 > > 详细

THC留学生讲解、data辅导、Python编程设计辅导、c++,Java讲解辅导R语言程序|讲解SPSS

Briefing

Talbot Heath Computers

The scenario is fictitious and any resemblance of company, data, or circumstances to any organization past or present is entirely coincidental.

OVERVIEW

Talbot Heath Computers (THC) has recently acquired a business which owns a small factory manufacturing very specialised computer-based measuring equipment (known in the company as "sensors", and selling for £200 each).

The Sales team believes that there is the potential for greater market share for their product. However, the new Operations manager, brought in by THC, sees the central sensor production activity, the Unit Assembly Department (UAD), as disorganized and a constraint on the overall production performance of the factory.

THC have commissioned a simulation-based study of the Unit Assembly Department to contribute information to discussions and decisions regarding the business problem of finding, from the possible options, the most effective way of increasing production output.

The whole factory works continuously for five days per week, Monday 0600 until Saturday 0600, then closes for the weekend. The labour and equipment is used in such a way that there are no interruptions in activity at shift change, lunch periods, or coffee/tea breaks (involving stand-by staff brought in, for those short periods, from elsewhere). Maintenance and equipment adjustment are carried out over the weekend (i.e. Saturday 0600 until Monday 0600) and do not prevent or disturb any department or item of equipment from continuing exactly where it left off at the end of the previous week.

The Unit Assembly Department receives pre-sorted kits of sensor parts (valued at £100) directly from the Warehouse (where the kits are put together) at regular intervals of 9 minutes (this time is governed by the design and resourcing of the Warehouse). Individual kits contain all the components required to make one sensor and, when they arrive in the UAD, the kits are stacked in an area of the Department designated as the Input Storage Point. This is the boundary from which the UAD takes responsibility.

There are currently three Assembly Stations, each equipped with a complex special-purpose device (costing £100,000) designed to facilitate sensor assembly from the kits, and each such station requires one Operator to function.

Analysis of shop-floor data indicates that the time for the Assembly task can be represented by a normal distribution with a mean of 30 minutes and standard deviation of 5 minutes (this includes an Operator taking a kit from the Input Storage Point and placing the assembled sensor on a roller table, known as the Holding Point, to wait for the next operation).

After Assembly, sensors are taken by a Technician (in order of Assembly completion) from the Holding Point to an Inspection Area for an activity known as Proving. This is carried out on one of series of purpose-built Test Rigs (costing £20,000 each), of which there are four. There are currently two Technicians. Overall, Proving consists of three steps:

1.A Technician setting up the sensor on a Test Rig in the Inspection Area ready for the Proving process and initiating that process by switching on the Test Rig (setting up and initiating consistently takes 4 minutes, including transfer from the Holding Point);
2.The Proving process itself (which must last for a minimum of 30 minutes, but which does not require a Technician present once started);
3.A Technician evaluating the results of the Proving process (the evaluation time being a constant 6 minutes), without moving the sensor from the Test Rig.

Assembly is a delicate task and, after that process, only 80% of sensors are placed directly on an Output Conveyor to go to Packing & Dispatch, the next department, taking 2 minutes. (UAD’s responsibility for each sensor ends when it is on the Output Conveyor.) Of the remainder, 2% of sensors are scrapped after Proving and placed by the Technician in a Rejects Chute (taking them out of the Department and the process, with no scrap value), again taking 2 minutes. A further 18% fail the Proving but are considered reclaimable and must be subjected to a further process in the Inspection Area, known as Diagnosis, to confirm the rectification action to be taken. The 2% and 18% failure rates are random and exhibit no trends or patterns.

Diagnosis is carried out by the Technician immediately following evaluation – with the sensor still on the Test Rig - and taking a time which is (negative) exponentially distributed with a mean of 7 minutes. By the end of Diagnosis the sensor has been removed from the rig. The concluding step of Diagnosis (and taking a time so short it can be ignored in this analysis) is stacking the sensor by the Assembly Stations ready to be Rectified by an Operator at one of those stations. Rectification is not the same activity as Assembly. The time for Rectification follows a normal distribution with a mean of 45 minutes and standard deviation of 8 minutes. Current practice is for Rectification of a defective unit to be given priority over Assembly of a new unit.

Rectified sensors are put at the same place as newly assembled sensors, i.e. the Holding Point, ready for a further Proving process.

Scope for expansion on the site is very limited, with space for two further Assembly stations, or two further Test rigs, or one of each. All employees are paid at the same rate of £400 per week. THC has no problem borrowing capital for investment, but charges it to subsidiaries, such as this one, at 10% p.a.


The Requirement
You are required to study the above scenario and address the following:
1.Construct a Simul8 model of the Unit Assembly Department, incorporating appropriate information collection, as a basis for the inquiries in Part 2 below. (A graphics mimic diagram is not compulsory.)
2.As if a consultant to THC, use the model to explore the business problem faced, giving attention to the following questions (producing further models and incorporating modifications or enhancements as may, in your judgment, be required).
a)What is your performance assessment of the existing Unit Assembly Department configuration (i.e. current equipment and staffing level), including information on output and bottlenecks?
b)How many Test Rigs are optimally required in the Inspection Area?
c)What difference in throughput would result from a Business Process Re-engineering initiative combining the roles of Operator and Technician?
d)How much might it be worth THC spending on quality improvements in Assembly to reduce the 2%/18% failure rates?
e)What other conclusions do you reach regarding the effectiveness of possible UAD resource changes (equipment or staffing), operating rules, or profitability?
3.Produce a written report of no more than 2500 words (not counting any title page, contents list, tables, diagrams, graphs or the Lesson learnt section- but the word count must be shown); the report to include:
a)the Conceptual model;
b)descriptions of the runs carried out, including your rationale for the selection and design of the runs used;
c)results and discussion concerning Part 2 above.

Assessment
You are required to conduct a simulation analysis of the UAD manufacturing area and then produce a report that documents your analysis. The objectives of your analysis are to arrive at a design that:
Has minimum work in progress (WIP) levels whilst maintaining a “sensible” level of manning
Demonstrates robustness towards shop floor disturbances.
Your analysis should consider the following areas: delivery and shipping patterns, batch size, hours of work, scrap, efficiencies.

You must submit the report, enclosing your basic Simul8 model and any variations used, plus any further variation(s) you may wish to include. A key factor in assessment will be the extent to which you show a grasp of simulation and modelling and, through its use, show insight into the system, problems and issues being investigated.
 

联系我们 - QQ: 99515681 微信:codinghelp
程序辅导网!