What are the principal methodologies for modeling and designing system?
The two principal methodologies for modeling and designing information systems are structured methodologies and object-oriented development. Structured methodologies focus on modeling processes and data separately. The data flow diagram is the principal tool for structured analysis, and the structure chart is the principal tool for representing structured software design. Object-oriented development models a system as a collection of objects that combine processes and data. Object-oriented modeling is based on the concepts of class and inheritance.
Compare object oriented and traditional structured approaches for modeling and designing systems.
Object oriented
- what is object oriented? Object oriented as basic unit of system analysis and design. It combines data and specific proses on those data. Data encapsulated in object can be accessed and modified only by operations or methods and associated with that object.
- objects have belong to a certain class and have features of that class. It may inherit structures and behaviors of a more general and ancestor class.
Class and inheritance
This figures illustrates how classes inherit the common features of their superclass.
- by the way, object oriented have more iterative and incremental than traditional structure development. It continue with three steps too and there are system analysis, design phase and implementation.
- because of the object reusable, object oriented development can potentially reduce time and cost of development.
Traditional structure
- its separate to many types of structure like process oriented, data flow diagram, data dictionary, process specifications, and structure chat. Structure mean a technique that we need to follow step by step and its progressive.
- Process oriented is focusing on modeling processes or actions that manipulate data and can separate the data from process.
- data flow diagram is a primary tool for representing the system’s component processes and flow of data between them and it offers logical graphic model of information flow. Other than that, it’s a high-level and low-level diagrams can be used to break processes down into successive layers of detail.
- data dictionary mean defines contents of data flows and data stores.
- process specifications is describe transformation occurring within lowest level of the data of data flow diagram.
- structure chart is a top-down chart which showing each level of design and relationship to other levels and place in overall design structure.
High-level structure chart for a payroll system
This structure chart shows that the highest or most abstract level or design for a payroll system, providing an overview of the entire system.
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Management Information Systems Test Bank
Chapter 13 Building Information Systems
1 True-False Questions
1) The most common form of IT-enabled organizational change is automation.
Answer: TRUE
2) Rationalization of procedures describes a radical rethinking of the business models.
Answer: FALSE
3) Systems development activities always take place in sequential order.
Answer:
FALSE
4) Faulty requirements analysis is a leading cause of systems failure and high systems
development costs.
Answer:
TRUE
5) End users should not be included in the design process, but must be involved later.
Answer:
FALSE
6) The amount of testing time needed for a new system is consistently underrated.
Answer:
TRUE
7) The system is not in production until conversion is complete.
Answer: TRUE
8) A data flow diagram offers a logical and graphical model of information flow, partitioning a
system into modules that show manageable levels of detail.
Answer: TRUE
9) Object-oriented development is more iterative and incremental than traditional structured
development.
Answer: TRUE
10) Object-oriented frameworks have been developed to provide reusable, semi-complete
applications a company can customize into finished applications.
Answer:
TRUE
11) Prototyping is more iterative than the conventional lifecycle.
Answer: TRUE
12) A problem with prototyping is that the systems constructed using this method may not be able
to handle large quantities of data in a production environment.
Answer: TRUE
13) End-user-developed systems can be completed more rapidly than those developed through the