1. What are the drawbacks of the spiral model of system development? (5)

1. It is difficult to assess the budget and schedule of the spiral model up front. Difficuly for planning purposes.
2. Risk assessment is difficult. Moreover, risk assessment skills are very difficult to come by. Risk assessment requires experienced personnel.
3. This technique is relatively new and untested compared to the waterfall model. Therefore, there is not much research to fall back on in times of crises.

1. What are the key problems of the traditional systems development life cycle? (5)

1. The traditional SDLC tends to be long and costly since each phase needs to be completed before the next.
2. Requirements determination is a key activity and is generally also a source of weakness.
3. There is a lack of user participation in later stages.
4. Changes in the software or version or underlying business process have disastrous results later on in the lifecycle.

1. Do you agree with the following statement? Explain your response. "If we’re behind schedule in a software project, we can always add more people to solve the problem." (5)

No. Adding more people may not help. New members have to learn about the project and the learning curve is expensive. It also adds to the number of communication and coordination mechanisms required which is also costly.

 

2. The sales representatives of an electronic equipment manufacturer have been asked to settle all customer disputes in future. A new on-line system will be developed for immediate customer dispute resolution. The customer service representatives currently take about a week to respond to a customer dispute. Thus new rules and procedures need to be developed for the new system. The development team feels that one major component of the new system will be a rule-based system; unfortunately, the team does not have prior experience in expert systems. How would you rate the level of risk in this project? Do you need any additional information? (5)

1. Requirements difficult to assess.
2. Development group has low experience.
3. Users do not have experience with dispute resolution.
4. Depending upon the size, project is high or very high risk.

A Danish furniture designer and manufacturer recently completed gathering data for a feasibility study for a proposed information systems project. Management is considering automating a portion of the materials requisition and ordering process for the company's manufacturing division. Currently, it is necessary to order the materials to produce items as product orders come in and, at the same time, to schedule the items for manufacturing. Each item is made up of different parts, components, and assemblies. The particular set and quantity of parts for each design is maintained on a bill of materials form. There is separate bill of materials for each manufactured product, and these bills must be updated frequently so that any design and engineering changes are reflected in the bill of materials used by the manufacturing division. Recently, the company has encountered difficulties in maintaining the files. Both the number of products manufactured and the volume of changes to bills are increasing. It is anticipated that keeping this file up-to-date will require hiring two more persons at $20/hr unless the process is automated. Since the firm is growing, further additions will undoubtedly have to be made to the file in the future.

There have been problems as well in ordering the material needed for production. Errors often occur, apparently because the ordering process is done by hand. When items are not ordered in time, production must be rescheduled. The resulting delays cause confusion and ill will among the manufacturing managers.

Sometimes too much material is ordered, in which case it builds up in inventory. Excessive inventory incurs unnecessary carrying costs for storage and handling (carrying costs currently average 25 percent per year). In general, the overall rate of excess inventory is about 2-1/2 percent on material requisitions of $50 million annually. Inventory errors are equally distributed between overages and underages. An automated system has been proposed to aid the requisition and ordering process. In this system, the bill of materials file will be automated and stored on magnetic disk, necessitating the acquisition of an extra set of disk drives. The cost of leasing the drive set is $1900. Although the materials files will have to be maintained on a regular basis, the current staff in the systems department should be able to handle this without the hiring of additional personnel.

The main advantage is expected to be a more systematic ordering of materials, with inventory overages and underages reduced. Furthermore, the organization as a whole is expected to benefit from this project. The actual users will be involved in the development of this project if it proves feasible, although they have not yet been contacted about it. Developing the system is estimated to require about 60 person-months of effort. In addition, the acquisition of a CASE package will cost $18,000. Analysts and programmers charge an average of $35/hour.

1. What information other than that provided does the committee need to determine feasibility? Indicate which aspect of feasibility will be evaluated, using the information requested. (10)

• Technical: schedule
• Economic: Training costs, maintenance costs, lifetime costs, cost of funds
• Operational: user reactions

2. Using only the estimated costs and benefits, assess the project's economic feasibility. (10)

• Assume 70 % error reduction
• Assume discount rate 12 %
• Find payback period, NPV and ROI.