Fourth Quiz

FIRST OBSERVATION AND ANALYSIS REQUIREMENT

Initial investigation

Concept of system investigation
System investigation here is done when there is or there is a gap in the difference (gap) between the purpose of the system and actual system conditions.To know what things have makes system fail, then an analyst need to do an investigation first before take an action to repair the system. Because with investigation, an analyst can more understand about the problem and the flow of their system.

The purpose of investigation is to show the real problem of the system
Why report of detection problem is not real?

The report of detection problem can be not real because of:

• Too ideal goal of system

• Lees of resource or attitude

• Measuring of system is not accurate

• Renewing goal of system (statement of goals is dated)

• The gap between the ideal and the current system is temporary and will decrease given patience.

In problem solving, is necessary to give explanation about:

• Defining the system which is working

• getting ideal of system consensus

• gap developing some alternatives for decrease the gap

• chose the best alternatives

Constraints System Investigation

In making an investigation, there are several problems that often arises, namely:

· Time

· Cost

· Science

· Politics

· Intervention

Recommendation

The result of investigation is a recommendation, is contain of below:

• No action is taken. Because didn’t found any problem. This is mean when there is no problems find in system we can’t take any actions.

• Maintenance system. Is done for small problem. System maintenance needs to maintenance small problems like when job description not runs very well. So we must solve that problem and after we solve it we must maintenance

• Improving ability or skill for user

• Consider for system modification globally

• Placing problem that happened into system development plan.

Tactics of investigation

Why tactics is needed?

• To find all problems

• Detect the cause of problem

• Determining correct solution

Tactics investigation is done in order to every element in system can get the offering solution without disturb their activity

Some tactics with can be done:

• Listen the performer of system

• Do not presolve the problem

• Compare stories

• Probe for logical inconsistencies

• Look for reluctant responses

• Observe your effect

• Avoid politics

Technical of investigation

Can be divided into two:

1. Direct
• Questionnaires
• Interview
• observation

2. Indirect
• Procedure flow
• Document review
• Sampling
• Tabular tools

Description of the system in present time
• Input
• Output
• Files
• Data elements
• Transaction and action document volume
• Data flow diagrams


Requirement analysis

Stage of intensive interaction between the systems analyst with the end user where the system shows the development team expertise to get feedback and trust so that the user get a good participation.

4 target in this process, wish reached :

• explain system completely

• instance ideal system information

• bring information system into ideal condition at present time, with pay attention from resources

• cheering on user’s conviction to system development

Some method to get requirement for analysis :

• -- answer and question

• - questionnaires

• - observation

•- - analysis procedure

• - document review


Resource problem in requirement analysis :

• - time

• - Cost

• - Skill

• - Technology

• - External factor

Documents from analysis requirement:

• Analysis direction: relationship with the end user, process monitoring, problems in data gathering.

• User needs: real needs, report needs, exercise needs, and new system influence.

• System constraint: explain time and cost constraint, skill, technology and external factor.

• Document kind data gathering instrument, statistic consensus, data flow according to physic and logical, first data element in data dictionary.

Generating system alternatives:

Strategy selection

- Distributed versus centralized processing

- - Change information decision from centralized data processing to decentralized end user responsibility center.

- Integrated versus dispersed database

3. - System planner must consider what kind of incoming data to database and incoming to file.

- Surround Strategy of System Development

4. Environs are important strategy in case overtake company because information system from other company possible different with company at moment.

Tactic choice

is done before operational planning choice

Operational planning choice

Operational planning choice can be categorized to:

• Input

- online versus offline data entry

- keyed versus machine readable data entry

- centralized versus decentralized data entry

• processing

- batch versus realtime record update

- sequential versus direct access to records

- single versus multiple user update of records

• output

- traditional vs turn around documents

- structured vs inquiry based reports

Selecting the proper system

1. some method of system comparison:

• break even point analysis

• payback period

• discounted payback period

• internal rate of return

2. cost categories:

· Hardware

· Software

· People

· Suppliers

· Telecommunications

· Physical sites

3. detailed cost:
Comparing the cost of information systems through the life of the system, analysts projected how the cost changes for the future and there are 3 models cost information system, namely Linear, and exponentially Step Function

Cost information system can occur only once and can also occur on an ongoing basis.

Cost information system that occur only once the cost on time and development costs that occur during the development of the system.

Cost information system that occur continuously among reccuring cost and operational cost where the cost of this is the case when the operating system information every day.

Information System Factor

Qualitative factor direct to best information system there are:

• reduce mistake state

• reduce time to solve mistake

• reduce perceptive time from alternative workstation

• increase time to supplying information

• raise system security

• increase update from active record

• raise user satisfied

Company Strategy Factor

• user satisfied

• increase selling state

• commitment between consumer and vendor

• product information marketing

The presentation Learning System

• shortly presentation

• reduce technically details

• presenting with clearly and use visual tools

• if use model, use tools likes laptop so could more informative

• pushed profit from information system proposal with some alternative appropriate with company’s condition

Continuing or not?

• If the company decided to develop the system, then the information department will do the next process, called design system process

• If not, then system development life cycle will stopped

• Often will find problem with studying system and usually top management will asked to do re processing with studying system.

• The model will explain several continuous state, and sometime the information department will creating decision to repeat the state before explain the studying system.

• With the alternative, decision to repeat a state before System Development Life Cycle (SDLC) or not, is called Go – No –Go Decision.

Pengembangan Sistem

Systems Development

The Importance of Developing an Information Systems

1. There are many problems appear of the old systems

2. Damage growth of organization’s

3. The reach for opportunities

4. There are many directives

The Purpose or Goal of Developing an Information System is:

* Analyze the problems

* The reach for opportunities

* Comply the request directives

The Organization’s Expectations after Implementing an Information System

* Performance

* Information

* Economy

* Control

* Efficiency

* Services

The Principles of Developing an Information System :

* System for Management

* The system is a Big investment

* Systems need educate person

* System development life cycle

* System development mustn't well organized

* Don't afraid to cancelled the project

* System Documentation

System development life cycle

1.Waterfall Model

The waterfall model is a sequential one, consisting of the following process areas:

• The requirements phase, in which the requirements for the software are gathered and analyzed, to produce a complete and unambiguous specification of what the software is required to do.
• The architectural design (analysis) phase, where a software architecture for the implementation of the requirements is designed and specified, identifying the components within the software and the relationships between the components.
• The design phase, where the detailed implementation of each component is specified.
• The code and unit test phase, in which each component of the software is coded and tested to verify that it faithfully implements the detailed design.
• The system integration and system test phase, in which the software is integrated to the overall product and tested.
• The acceptance testing phase, where tests are applied and witnessed to validate that the software faithfully implements the specified requirements.

2.Model Spiral

The next step in the spiral life cycle model is to evaluate these different alternatives based on the objectives and constraints. This will also involve identifying uncertainties and risks involved. The next step is to develop strategies that resolve the uncertainties and risks. This step may involve activities such as benchmarking, simulation and prototyping. Next, the software is developed by keeping in mind the risks. Finally the next stage is planned.

The next step is determined by remaining risks. For example, its performance or user-interface risks are considered more important than the program development risks. The next step may be evolutionary development that involves developing a more detailed prototype for resolving the risks. On the other hand, if the program development risks dominate and previous prototypes have resolved all the user-interface and performance risks; the next step will follow the basic waterfall approach.

The risk driven nature of the spiral model allows it to accommodate any mixture of specification-oriented, prototype-oriented, simulation-oriented or some other approach. An important feature of the model is that each cycle of the spiral is completed by a review, which covers all the products developed during that cycle, including plans for the next cycle. The spiral model works for developed as well as enhancement projects.

In round one, a concept of operation is developed. The objectives are stated more precisely and quantitatively and the cost and other constraints are defined precisely. The risks here are typically whether or not the goals can be met within the constraints. The plan for the next phase will be developed which will involve defining separate activities for the project. In round two the top-level requirements are developed. In succeeding the rounds, the actual development may be done. This is a relatively new model and can encompass different development strategies. In addition to the development activities, it incorporates some of management and planning activities into the model. For high-risk projects this might be a preferred model.

3.Iterative model

The four basic process areas of the iterative model are:

• The requirements phase, in which the requirements for the software are gathered and analyzed. Iteration should eventually result in a requirements phase that produces a complete and final specification of requirements.
• A design phase, in which software architecture and components to meet the requirements are designed; this may be a new design, or an extension of an earlier design.
• An Implementation phase, when the software is coded, integrated and tested.
• A review phase, in which the software is evaluated, the current requirements are reviewed, and changes and additions to requirements proposed.

The design phase develops the architecture that forms the foundation for the system and is critical to the success of the subsequent iterations. For obvious reasons, the design must facilitate change, and be robust enough to support unforeseen, future implementations. For each cycle of the model, a decision has to be made as to whether the software produced by the cycle will be discarded, or kept as a starting point for the next cycle. This approach has been referred to as incremental prototyping. However, the temptation to create a quick prototype that cannot scale-up must be resisted--typically, this is not prototyping, although it could be. The cycle is complete when the requirements have been satisfied, and the release to the customer is made. On some iterations--particularly early ones, a decision may have to be made to abandon the approach and begin anew.

Approach of system Development

1.Classical approach versus structured approach (depends from methodology)

• Classical approach is a traditional approach constitute developing on a priority of the rural the system wich is follow the steps of life cycle without good supplied with tools and tehcnics.

The problems that emerge in the classical approach is :

- Developing the software would be hard

This approach not extend tools and technics to developing the system finally software developing process is not directed and difficult to accupation job with the programmers.

- The cost of maintain the system would be expensive

Cost of maintain would be expensive because documentation system less structured and complete.

- The possibility of the faults system

This approach not prepare the manner of system testing then so the possibility of the faults system

- The sucessful of the system not gauaranted

- Would be a lot of problems to applying the system

• Structural approach stared in early 1970 when this approach use tools and techniques that was needed on developing the system witch is it structure defining clearly. By this , complex approach in organizing can be resolve and the result of it will be easy to rear, flexible, satisfied the user, good documentatoin ,on time, on budged for the developer, rising the productivity, and fault free.

2.Piecemeal approach versus systems approach (depend from the target)

• Piecemeal approach is developing system that pressed to an application without give attention to whole organisation.

• System approach pay attention information system as one unity integrated for each application and also pressed on achieving target to the whole organisation.

3.Bottom-up approach versus Top-down approach (depend from the how to determine the needed of system)

• Bottom–up approach started from low organisation level where the level transaction to do. This approach is the characteristic from classic approach.

• Top-Down approach is the opposite from Bottom-Up approach and characteristic from structured approach .

4.Total-system approach versus Modular approach(depend on how does it expand)

• Total-system approach is expand the system comprehensively at the same time and the characteristics from classic approach.

• Modular approach tries to break the complicated system to bezrp simple modulo. That can be easier to understand and to develop. It is the characteristics from structured approach.

5.Great loop approach versus Evolutionary approach(depends on the technology that use)

• Great loop approach is total changed at the same time with sophisticated technology. This change is contain risk too expensive and hard developed.

• Evolutionary approach is only apply the sophisticated technology for application needed.

Method of Development System

Methodology is methods unity, procedure, conception of job, rules and postulats that use by knowledge,art or another diciplines.

Method is a way,technical systematic to do something.

Algoritma is procedure steps to slove the problem.

The Three Classifications of Development methodology

Functional Decomposition Methodologies
Data-Oriented Methodologies
- Data-flow Oriented Methodologies
- Data-structure Oriented Methodologies
Prescriptive Methodologies
- ISDOS(Information System Design and Optimization System)
- PLEXSYS
- PRIDE
- SDM/70(System Development Methodology/70)
- SPECTRUM

- SRES(Software Requirement Engineering System) and SREM(Software Requirement Engineering Methodology)

- Chapin's Approach
- DBO(Design by Objective)
- PAD
- HOS
- MSR
- PDL

Mention Tools for Developing a system

The Specific Characteristic Graphical Tools for Developing Systems

- HIPO Diagram

- Data Flow Diagram

- Structured Chart

- SADT Diagram

- Warnier/Orr Diagram

- Jakson's Diagram

The General Characteristic Graphical Tools for Developing System

- Activity Charting

1. Systems Flowchart
2. Program Logic Flowchart
3. Detailed Computer Program Flowchart
4. Paperwork Flowchart/Form Flowchart
5. Database Relation Flowchart
6. Process Flowchart
7. Gantt Chart

- Layout Charting

1. Working Distribution Chart
2. Organization Chart

Non-racial Tools for Developing Systems :

1. Data Dictionary
2. Structured English
3. Pseudo code

Techniques that can be used in development system :

1. Project management technique, that is CPM (Critical Path Method) and pert (program evaluation and review technique). This technique is used for project scheduling.

2. Fact finding techniques, that is technique that can be used to gather data and find facts in study existing system, that is:
Interview

Observation
Questionnaire
Sample collecting

3. Cost-effectiveness analysis or cost benefit analysis

4. Technique to run meeting

5. Technique inspection/walkthrough.

Analysis System and Programmer


Analysis ststem is one who analyze to study and identify that probelms and determine user need system.

Programmer is one who write program code to a certain application based on has planned to get up that made by system analyst.

Knowledge And Skill That Need System Analyst

• Knowledge and skill about data processing technique, computer technology and computer programming.

Technical skill that must has belong skill in tool use and technique for application software development with skill in use computer. Technical knowledge that must has cover erudition about hardware, data communication technology, computer languages, os, utilities, and another.

• Knowledge about business in general.

This knowledge be wanted so that system analyst can communicate with system user.

• Knowledge about quantitative method.

System analyst use many quantitative methods in build application models, like dynamic programming, regresion, network, decision tree, trend, simulation and other as it.

• Trouble-shooting skill.

System analyst must has ability to put complex troubleshoots that is faced by business, divide problem into parts, analyze it and then must can return composed to be a system can overcome troubleshoots.

• Communication skill delivers staff.

System analyst must has ability to hold communication either through tongue or article. This skill is need in interview, presentation, meeting and report maker.

• Skill builds connection delivers staff.

Human is factor critical insides system and human character one with another differ, so that need a skill to build connection delivers staff.

Refrences :

1. www.snyders.us/qa-iterative.htm

2.HM, Jogiyanto. Analisis & Desain Sistem Informasi. Yogyakarta: ANDI,2007.