Fourth Quiz

Commencement Monitoring, Analysis Requirement

Concept of System Investigation

• Gap between system purpose and the real conditions of system
• Detection problem statement is not real:

• The system purpose is too ideal
• Less of resource or attitude
• System measurement is not accurate
• Using Out of date system purpose
• Different between idle system and temporary system.

• Problem solving:

• Define the running system investigation with details specified
• Obtain the consensus of ideal system
• Developing several alternatives
• Selecting the best alternative

• The investigation purpose show problem that occurred.

Constraints on investigation system:

When we doing the investigation, there are several constraints that are appear, such as:

• Time
• Cost
• Knowledge
• Politic
• Involved

Recommendation

The result of investigation is a recommendation that includes:

• Take no action because the problem is not found
• Doing system maintenance there are small problems
• Increase the user ability or user skill
• Consider about modify system totally

Settle the occurred problem into system development planning.

Investigation tactic

§ Why we need tactic for?

§ To find whole problem

§ To know the problem motive

§ To find the proper solution

§ It’s doing to make all of system element can accept the solution without annoy their activities.

§ Several Tactics that we can doing:

§ Listen to the opinion of system subject.

§ Don’t give the beginning of problem solving

§ Consider

§ Care about inconsistency logical problem

§ Direct :

§ Questionnaire

§ Answer and Question

§ Observation

§ Indirect :

§ Current procedure

§ Document learning

§ Sample

§ Tabular

§ Input

§ Output

§ File

§ Data Element

§ Volume of Transaction and action document

§ Data flow diagram

Analysis Requirement

Intensive interaction between system analyst and end user where system development team show their ability to get conception and user believe until we get best participation.

§ Four purposes which want to attain:

§ Explain the ideal system information

§ Encourage

§ Method

§ Answer and Question

§ Questionnaire

§ Observation

§ Analysis Procedure

§ Document observation

§ Resource constraint

§ Time

§ Money

§ Skill

§ Technology

§ External Factor

§ Analysis requirement document

§ Analysis Directive: relation with end user, process observation, problem in collect data.

§ User Requirement: Real requirement, statement requirement, training requirement and influence of new system.

§ System constraint: roll out consider of time and cost, skill, technology and external factor.

§ Document in the form of data collected, statistic consensus, logically and physically data flow, current data element in data set.

Generating System Alternatives

How to make the current system is like ideal system?

§ Make alternative to solve the information system problem

§ Applying the best alternative prudently

Strategy selection

§ Distributed versus centralized processing

The change of information decision from centralized data processing into decentralized end user responsibility center

§ Integrated versus dispersed database

System designer have to consider what the data that be included into data base and the data that be included into File.

§ Surround Strategy of System Development

Surroundings of strategy are important in business take over because information system from other business may different with current business.

§ Tactics Selection

Doing before operational design selection:

§ Operational design selection

Design selection could be categorized into:

§ Input

§ Online Vs Off Line Data Entry

§ Keyed Vs Machine Readable Data Entry

§ Centralized Vs Decentralized Data Entry

§ Processing

§ Batch Vs real time record update

§ Sequential Vs Direct Access to records

§ Single Vs Multiple User update of records

§ Output

§ Traditional Vs Turn Around Documents

§ Structured Vs Inquiry based reports

Selecting the Proper System

§ Consider tactics: system compared by cost and profit relatively. Three methods to say A system more excellent than other system are :

1. A have a cost more inferior than B and the profit of both are same
   
2. A have a cost more inferior than B and A result profit is more much than B.
   
3. A and B have a some cost but A's profit is more much
   

§ System comparison methods :

§ Break Even point Analysis

§ Payback Period

§ Discounted Pay Back period

§ Internal Rate of Return

§ Cost categories

§ Hardware

§ Software

§ People

§ Supplier

§ Telecommunications

§ Physical sites

§ Cost detailed:

Compare information system cost by system live, analyst forecasting the change of cost for future and there are three information system models, include: Linear, Exponential, and Step function.

§ Information System cost can happen in once and continuous.

§ Onetime cost is Information system cost that happens once and development cost that happen when system is developing.

§ Information system that happen continuously such as recurring cost and operational cost where this cost happen if information system is operated every day.

Information system Factor:

Qualitative factor that aim proper information system outcome are:

§ Fault decrease

§ Decrease the time for fault repair

§ Decrease perceptive time of alternative workstation

§ To Increase system security

§ To Increase the update of source of active record.

§ To Increase user satisfied

Business strategy factor

§ Consumer satisfied

§ The selling level raise

§ Consumer and vendor commitment

§ Information of Product Marketing

Presentation System Learning

§ Doing concise presentation

§ Decrease elaboration technique in presentation

§ Use visual auxiliary to define explicitly.

§ To make informative presentation, used auxiliary especially if we presentation with model.

§ Pressure the benefit of information system proposal with several alternative appropriate business conditions.

Decision to continue or not

§ If business makes a decision to develop the system, then information department will do the next process that is System Design Process.

§ In contrast, System Development Life Cycle is stopped.

§ Top Management will request to repeat the system study if problem with system study is found.

§ Model will explain about repeated phase and sometime information department will make decision to repeat the phase before explain about system study.

§ With Alternative, A decision to repeat System Development Life Cycle phase or not is called Go-No-Go Decision.

Third Quiz

Part-2 System Development

The importance of developing an information system

System development is change the whole of old system to arrange the new system or just repair the present system. The old system need to repair is caused by several matters, such as:

1. Problems

There are several problems that appear in old system, such as:

− Disorganize

Disorganize in old system is caused the old system can't operate appropriately.

− The growth of organization

The growth of organization make we have to create the new system. The grown-up of organization such as:

a. The need for information is arise.

b. The advance of data manufacture

c. Differences of new accountancy principle

2. Opportunities

Increase the equipping of information until the information can used to make a decision.

The opportunities are like: market opportunity, costumer services.

3. Directives

There are some instructions from manager or alteration of government’s law.

The purpose or goal of developing an information system

1. Resolve the problems

2. Reach the Opportunities

3. Implementation the Directives

The organization’s expectations after implementing an information system

1. Performance

It's measured by throughput and response time.

2. Information

Increase the quality of information.

3. Economy

Increase the benefit and discharge the cost.

4. Control

Advance control to detection and do the corrective action.

5. Efficiency

It’s measured by output divide with input.

6. Services

Advance system services.

The principles of developing an information system

1. System is developing for management

2. System is the great investment

Investigate the entire alternative to minimize the lost opportunity cost and to find the great investment. The great investigation must be precious, the investment is has a value if the use of it more effective than the cost to had it. We can use cost-benefit analysis or cost-effectiveness to determine the precious of investment.

3. System need educated person

4. System development life cycle

Provides overall framework for managing systems development process.

5. System development process is must not in series

6. Don’t be afraid to canceled the project

7. System Documentation

System development life cycle models

1. The Waterfall Model

In the waterfall approach, the whole process of software development is divided into separate process phases.

The phases in waterfall model are:

− Requirement

All possible requirements of the system to be developed are captured in this phase.

− Design

Before us starting the actual coding, it is important to understand what we are going to create. The requirement specifications from first phase are studied in this phase and we can prepare the system design.

− Implementation

Activities in this phase: construct, test, train users, and install new system.

− Verification, include in this phase:

Testing: focus in internal logic of software and external function(find the fault and certain the input-output)

Coding is process convert design into language that machine is known use programming language.

− Maintenance: the meaning of maintenance is how we adapt to changes.

2. Iterative Model

1. Adopt sequential linier and prototype model.

2. The project is dividing into small parts. This allows the development team to demonstrate result earlier on in the process and obtain valuable feedback from system users.

3. With iterative model, work activities are repeated.

4. Each iteration refines previous result.

5. Starting from the model/requirements through to the testing/deployment

6. There are a series of mini project for each iteration.

3. Spiral Model

1. Spiral Model is developed to combine the best of the life cycle and prototyping models.

− Use an evolutionary approach suggested by the prototyping paradigm

− Maintains systematic stepwise approach of the life cycle model, but incorporates it in an iterative framework

2. This model adds risk analysis component to minimize risk during development

3. Four major activities in this model are:

− Determine objectives

Objectives are determined, possible obstacles are identified and alternative approach are weighed

− Risk analysis (Identify and resolve risk)

Possible alternatives are examined by the developer and associated risk or problems are identified. Resolution of the risk are evaluated and weighed in the consideration of project continuation.

− Development and Test

Detail requirement are determined and the software piece is developed.

− Planning the next Iteration

The costumer is given an opportunity to analyze the result of the version created in engineering step and to offer feedback to the developer.

Approaches of developing a system

Classical Approach vs Structured Approach

Classical Approach

1. Use System Development Life Cycle phase, but this approach not give the manual how to do the phase.

2. System User is not stay with.

3. The problems that appear if we use this approach are:

Difficult to expand, great of maintenance cost, minimum of success, complicate in implementation.

Structured Approach

1. Use tools like data flow diagram.

2. System user is stay with.

Piecemeal Approach vs Systems Approach

Piecemeal Approach

1. Emphasize in applications or activities.

Systems Approach

1. View the system as integrated element.

2. Emphasize to get a target

Bottom-up Approach vs Top-down Approach

Bottom-up Approach

1. Start from bottom level, which is operational level

2. Bottom approach is classical approach feature.

3. Known as data-analysis

Top-down Approach

1. Start from top level that is strategy planning level.

2. Top-down approach is structured approach feature.

3. Known as decision-analysis.

Total-system Approach vs Modular Approach

Total-system Approach

1. Expand the system together and comprehensive.

2. Total-system Approach is classical approach feature.

Modular Approach

1. Divide the system in simple a part.

2. That expand system is actual.

3. Modular Approach is structured approach feature.

Great-loop Approach vs Evolutionary Approach

Great-loop Approach

1. Expand the system at once using sophisticates technology.

2. High risk and cost.

Evolutionary Approach

1. Appling sophisticates technology for special application.

2. Developed with requirement.

3. Economical and go along with technology development.

The meaning of methodology, method and algorithm

Methodology

Methodology is methods that used in science or comprehensive guidelines to follow for completing every System Development activity.

Method

Method is a systematic way to do something.

Algorithm

Algorithm is the sequence of procedure to resolve the problem.

Three classifications of development methodology

Functional decomposition

Emphasize at dividing a system into small parts or subsystem. This make the system easy to learn, design and applied.

Data-oriented

This methodology emphasizes at characteristic of data that processing and classified at:

1. Data-flow oriented methodologies, based in dividing system into modules according a element data type and behavior of logic module. Include in this methodologies are: SADT (Structured Analysis and Design Technique), Composite Design and SSAD (Structured System Analysis and Design).

2. Data-structured oriented methodologies, emphasize at input-output structure. Include in these methodologies are: JSD (Jakson’s systems development) and Warnier/Orr (W/O)

Prescriptive

Include in these methodologies are:

1. ISDOS (Information System Design and Optimization System),

2. PLEXIS, transformation a statement of high level computer language into executable code.

3. PRIDGE, a complex software that used to analyze and design system, data management, project management and documentation.

4. SDM/70 (System Development Methodology/70)

5. SPECTRUM,

6. SRES (Software Requirement Engineering System) and SREM(Software Development System).

7. Other prescriptive methodologies : Chapin’s approach, DBO (Design By Objective), PAD (Program Analysis Diagram), HOS (Higher Order Software), MSR (Meta Stepwise Refinement) and PDL (Program Design Language).

Tools for developing a system

1. Graphic models

1. HIPO diagram, it’s used in HIPO methodology and other methodology.

2. Data flow diagram, it’s used in structured system analysis and design.

3. Structured chart, it’s used in structured system analysis and design.

4. SADT diagram, it’s used in SADT methodology.

5. Warnier/Orr diagram it’s used in Warnier/Orr methodology.

6. Jakson’s diagram it’s used in Jakson System Development.

2. Charting Tools

− Activity charting: drawing activity, such as:

1. System flowchart

2. Program flowchart

3. Paperwork flowchart

4. Form flowchart

5. Gantt chart

− Layout charting

− Personal relationship charting

Techniques used in developing a system

The techniques that used in developing a system is not only specifically for one methodology, but also it can used in all of methodologies. The techniques that can be used are:

1. Project Management Techniques,

Such as: CPM (Critical Path Method) and PERT (Program Evaluation and Review Technique). It can be used for project scheduling.

2. Fact Finding Techniques

Fact Finding Techniques are techniques can be used for collection data and finding fact in learning system activity. These techniques are:

-Interview

-Observation

-Questionnaires

-Sampling

3. Cost effectiveness analysis/ Cost benefit analysis

4. Meeting Techniques

5. Walkthrough Techniques

The differences of being a system analyst and a programmer

System analyst:

1. Learning the problem and determine the requirement of system user to identify solution of the problem.

2. Be a mediator between system user and programmer especially about their knowledge.

Programmer:

1. Programmer writing the code programs of the application according design which made by system analyst.

2. Programmer’s knowledge is limited by computing technology, computer system, utilities, and programming language.

The knowledge’s a system analyst should posses

1. Knowledge and skills about data manufacture method, computer technology, and computer programming.

2. Knowledge about business in generally

3. Knowledge about quantitative method

4. Problem solving skills

5. Interpersonal communication skills

6. Interpersonal relationship skills