Kendall & Kendall Systems Analysis and Design, 9e PDF

1 Kendall & Kendall Systems Analysis and Design, 9e Systems, Roles, and Development Methodologies Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0  Learning Objectives Understand the need for systems analysis and d...

1 Kendall & Kendall Systems Analysis and Design, 9e Systems, Roles, and Development Methodologies Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0  Learning Objectives Understand the need for systems analysis and design in organizations. Realize what the many roles of the systems analyst are. Comprehend the fundamentals of three development methodologies: SDLC The agile approach Object-oriented systems analysis and design Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0  Information—A Key Resource Fuels business and can be the critical factor in determining the success or failure of a business Needs to be managed correctly Managing computer-generated information differs from handling manually produced data Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0  Major Topics Fundamentals of different kinds of information systems Roles of systems analysts Phases in the systems development life cycle as they relate to Human-Computer Interaction (HCI) factors CASE tools A Computer-Aided Software Engineering (CASE) tool is a software package that provides support for the design and implementation of information systems Open Source Software Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0  Need for Systems Analysis and Design Installing a system without proper planning leads to great user dissatisfaction and frequently causes the system to fall into disuse Lends structure to the analysis and design of information systems A series of processes systematically undertaken to improve a business through the use of computerized information systems Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0  Roles of the Systems Analyst The analyst must be able to work with people of all descriptions and be experienced in working with computers Three primary roles: Consultant Supporting expert Agent of change Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0  Qualities of the Systems Analyst Problem solver Communicator Strong personal and professional ethics Self-disciplined and self-motivated Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0  Systems Development Life Cycle (SDLC) The systems development life cycle is a phased approach to solving business problems Developed through the use of a specific cycle of analyst and user activities Each phase has unique user activities Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0  The Seven Phases of the Systems Development Life Cycle (Figure 1.1) Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0  Incorporating Human-Computer Interaction (HCI) Considerations The demand for analysts who are capable of incorporating HCI into the systems development process keeps increasing, as companies begin to realize that the quality of systems and the quality of work life can be improved by taking a human-centered approach at the outset of a project Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0 1- Identifying Problems, Opportunities, and Objectives Activity: Interviewing user management Summarizing the knowledge obtained Estimating the scope of the project Documenting the results Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0 1- Identifying Problems, Opportunities, and Objectives Output: Feasibility report containing problem definition and objective summaries from which management can make a decision on whether to proceed with the proposed project Feasibility report summarizing problem definition and objectives to help management decide whether to proceed with the project. ‫ش‬ Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0 2- Determining Human Information Requirements Activity: Interviewing Sampling and investing hard data Questionnaires Observe the decision maker’s behavior and environment Prototyping Learn the who, what, where, when, how, and why of the current system Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0 2- Determining Human Information Requirements Output: The analyst understands how users accomplish their work when interacting with a computer Begin to know how to make the new system more useful and usable Know the business functions The analyst learns how users interact with the system, identifies improvements for usability, and understands key business functions. Have complete information on the: People Goals Data Procedure involved Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0  3- Analyzing System Needs Activity: Create data flow, activity, or sequence diagrams Complete the data dictionary Analyze the structured decisions made Prepare and present the system proposal Output: Recommendation on what, if anything, should be done Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0  Sequence Diagram is a type of interaction diagram because it describes how—and in what order—a group of objects works together. These diagrams are used by software developers and business professionals to understand requirements for a new system or to document an existing process. Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0 4- Designing the Recommended System Activity: Design procedures for data entry Design the human-computer interface Design system controls Design database and/or files Design backup procedures Output Model of the actual system Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0  5- Developing and Documenting Software Activity: System analyst works with programmers to develop any original software Works with users to develop effective documentation such as (Process ,Planning ,Estimate ,Standards ,Metrics ,Scheduling , Product ,System documentations ) Programmers design, code, and remove syntactical errors from computer programs Document software with help files, procedure manuals, and Web sites with Frequently Asked Questions Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0 5- Developing and Documenting Software Output: Computer programs System documentation Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0 6- Testing and Maintaining the System Activity: Test the information system System maintenance Maintenance documentation Output: Problems, if any Updated programs Documentation Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0 7- Implementing and Evaluating the System Activity: Train users Analyst plans smooth conversion from old system to new system Review and evaluate system Output: Trained personnel Installed system Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0  Some Researchers Estimate that the Amount of Time Spent on Systems Maintenance May Be as Much as 60 Percent of the Total Time Spent on Systems Projects (Figure 1.2) Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0  The Impact of Maintenance Maintenance is performed for two reasons: Removing software errors Enhancing existing software Over time the cost of continued maintenance will be greater than that of creating an entirely new system. At that point it becomes more feasible to perform a new systems study. Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0  Resource Consumption over the System Life (Figure 1.3) Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0  Approaches to Structured Analysis and Design and to the Systems Development Life Cycle Traditional systems development life cycle CASE systems development life cycle (A Computer-Aided Software Engineering (CASE) tool is a software package that provides support for the design and implementation of information systems ) Object-oriented systems analysis and design Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0  Case Tools CASE tools are productivity tools for systems analysts that have been created explicitly to improve their routine work through the use of automated support Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0  Reasons for Using Case Tools Increasing analyst productivity Improving analyst-user communication Integrating life cycle activities Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0 Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0  The Agile Approach Based on: Values Principles Core practices Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0  Agile Values Communication Simplicity Feedback Courage Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0  Four Agile Resources Resources are adjusted to ensure successful project completion Time Cost Quality Scope Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0  Five Stages of Agile Development Exploration Planning Iterations to the first release Productionizing Maintenance Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0 Agile Project Development Process (Figure 1.5) Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0  Object-Oriented (O-O) Systems Analysis and Design Alternate approach to the structured approach of the SDLC that is intended to facilitate the development of systems that change rapidly in response to dynamic business environments Analysis is performed on a small part of the system followed by design and implementation Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0  Object-Oriented (O-O) Systems Analysis and Design The cycle repeats with analysis, design, and implementation of the next part and this repeats until the project is complete Examines the objects of a system Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0  Unified Modeling Language (UML) Phases Define the use case model: Use case diagram Use case scenarios Create UML diagrams Develop class diagrams Draw state chart diagrams Modify the UML diagrams Develop and document the system Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0  Statechart example Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0 Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0  Choosing a Method Choose either: SDLC Agile Object-oriented methodologies Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0  When to Use SDLC Systems have been developed and documented using SDLC It is important to document each step Upper level management feels more comfortable or safe using SDLC There are adequate resources and time to complete the full SDLC Communication of how new systems work is important Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0  When to Use Agile There is a project champion of agile methods in the organization Applications need to be developed quickly in response to a dynamic environment A rescue takes place (the system failed and there is no time to figure out what went wrong) The customer is satisfied with incremental improvements Executives and analysts agree with the principles of agile methodologies Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0  When to Use Object-Oriented The problems modeled lend themselves to classes An organization supports the UML learning Systems can be added gradually, one subsystem at a time Reuse of previously written software is a possibility It is acceptable to tackle the difficult problems first Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0  Open Source Software An alternative of traditional software development where proprietary code is hidden from the users Open source software is free to distribute, share, and modify Characterized as a philosophy rather than simply the process of creating new software Examples: Linux Operating System, Apache Web Server, Mozilla Firefox Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0  Four Types of Open Source Communities: Ad hoc Standardized Organized Commercial Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0  Six Key Dimensions that Differentiate Open Source Communities General structure Environment Goals Methods User community Licensing Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0  Reasons for Participating in Open Source Communities Rapidity with which new software can be developed and tested Faster to have a committed group of experts develop, test, and debug code This fosters creativity Have many good minds work with innovative applications Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0  Reasons for Participating in Open Source Communities Potential to reduce development costs Bolster their self-image Contribute something worthwhile to the software development community Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0  Open Source Contribution and Differentiation Contributions to the open community and differentiation from the open community are for the following reasons: Cost Managing resources Time it takes to bring a new product to the market Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0  Reasons for Analyst Participation in the Open Source Community Curiosity about software benefits Achieve collective design Incorporate open source software design into: Proprietary products Processes Knowledge IT artifacts Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0  Collective Design Through a process of collective design the IT artifact is imbued with Community and organizational structures Knowledge Practices Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0  Summary Information is a key resource Integration of traditional systems with new technologies Roles and qualities of the systems analyst The systems development life cycle CASE tools Agile systems development Object-oriented systems development Open source systems Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0  Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall Kendall & Kendall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall 1-0