INTRODUCTION TO SYSTEM ENGINEERING

SYSTEM ENGINEERING CONCEPT

Computers are fast becoming our way of life and one cannot imagine life without computers in today’s world. You go to a railway station for reservation, you want to web site a ticket for a cinema, you go to a library, or you go to a bank, you will find computers at all places. Since computers are used in every possible field today, it becomes an important issue to understand and build these computerized systems in an effective way.

Building such systems is not an easy process but requires certain skills and capabilities to understand and follow a systematic procedure towards making of any information system. For this, experts in the field have devised various methodologies. Waterfall model is one of the oldest methodologies. Later Prototype Model, Object Oriented Model, Dynamic Systems Development Model, and many other models became very popular for system development. For anyone who is a part of this vast and growing Information Technology industry, having basic understanding of the development process is essential. For the students aspiring to become professionals in the field a thorough knowledge of these basic system development methodologies is very important.
In this web site we have explored the concepts of system development. The web site starts with the system concepts, making the reader understand what does system mean in general and what are information systems in specific. The web site then talks about the complete development process discussing the various stages in the system development process. The different types of system development methodologies, mentioned above, are also explained.
This tutorial is for beginners to System Analysis and Design (SAD) Process. If you are new to computers and want to acquire knowledge about the process of system development, then you will find useful information in this tutorial. This tutorial is designed to explain various aspects of software development and different techniques used for building the system. This tutorial is a good introductory guide to the need and overall features of software engineering.
This tutorial is designed to introduce Software Engineering concepts to the upcoming software professionals. It assumes that its reader does not know anything about the system development process. However it is assumed that the reader knows the basics of computers.

What is Software Engineering?

Software Engineering is the systematic approach to the development, operation and maintenance of software. Software Engineering is concerned with development and maintenance of software products.
The primary goal of software engineering is to provide the quality of software with low cost. Software Engineering involves project planning, project management, systematic analysis, design, validations and maintenance activities.

Analysis, design, and development systems, products, or services requires answering several fundamental questions:

·         WHAT is a system?

·         What is included within a system’s boundaries?

·         WHAT role does a system perform within the User’s organization?

·         What mission applications does the system perform?

·         WHAT results-oriented outcomes does the system produce?

These fundamental questions are often difficult to answer. If you are unable to clearly and concisely delineate WHAT the system is, you have a major challenge. Now add the element of complexity in bringing groups of people working on same problem to convergence and consensus on the answers. This is a common problem shared by Users, Acquirers, and System Developers, even within their own organizations.
At the end of this lesson you would be able to know about system's concepts, characteristics and various types of Information Systems. You would also be able to understand the system development process.

People often confuse the concepts of systems, products, and tools. To facilitate our discussion, let’s examine each of these terms in detail.

System Context

We defined the term system earlier in this section. A system may consist of two or more integrated elements whose combined—synergistic—purpose is to achieve mission objectives that may not be effectively or efficiently accomplished by each element on an individual basis. These systems typically include humans, products, and tools to varying degrees. In general, human-made systems require some level of human resources for planning, operation, intervention, or support.

Product Context

Some systems are created as a work product by other systems. Let’s define the context of product: a product, as an ENABLING element of a larger system, is typically a physical device or entity that has a specific capability—form, fit, and function—with a specified level of performance.
Products generally lack the ability—meaning intelligence—to self-apply themselves without human assistance. Nor can products achieve the higher level system mission objectives without human intervention in some form. In simple terms, we often relate to equipment-based products as items you can procure from a vendor via a catalog order number. Contextually, however, a product may actually be a vendor’s “system” that is integrated into a User’s higher-level system. Effectively, you create a system of systems (SoS).
Example
1. A hammer, as a procurable product has form, fit, and function but lacks the ability to apply its self to hammering or removing nails.
2. Ajet aircraft, as a system and procurable vendor product, is integrated into an airline’s system and may possess the capability, when programmed and activated by the pilot under certain conditions, to fly.

Tool Context

Some systems or products are employed as tools by higher level systems. Let’s define what we mean by a tool. A tool is a supporting product that enables a user or system to leverage its own capabilities and performance to more effectively or efficiently achieve mission objectives that exceed the individual capabilities of the User or system.
Example
1. A simple fulcrum and pivot, as tools, enable a human to leverage their own physical strength to displace a rock that otherwise could not be moved easily by one human.
2. A statistical software application, as a support tool, enables a statistician to efficiently analyze large amounts of data and variances in a short period of time.