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CHAPTER 4 : SYSTEM DESIGN - Coggle Diagram
CHAPTER 4 : SYSTEM DESIGN
4.1Understand user interface design
4.1.1 User Interface Design (UI)
Evolution of the User Interface
, the user interface mainly consisted of process-control screens that allowed the user to send commands to the system.
That approach worked well with traditional systems that simply transformed input data into structured output
User-centered system
Requires an understanding of human-computer interaction and user-centered design principles
Human-Computer Interaction
Human-computer interaction (HCI) describes the relationship between computers and people who use them to perform their jobs
Then came the graphical user interface (GUI), which was a huge improvement, because it used icons, graphical objects, and pointing devices.
Main objective is to create a user-friendly design that is easy to learn and use
Principles of user-centered design
Understand the Business
Maximize Graphical Effectiveness
Use Models and Prototypes
Focus on Usability
Invite Feedback
Document Everything
4.1.2 User Interface Design Guidelines
Design a transparent interface
Create an interface that is easy to learn and use
Enhance user productivity
Make it easy for users to obtain help or correct errors
Minimize input data problems
Provide feedback to users
Create an attractive layout and design
Use familiar terms and images
Think Like a User
4.1.3 User Interface Components
Screen Elements & Controls
Menu bar
Toolbar
Command button
Dialog box
Text box
Toggle button
List box – scroll bar
Drop-down list box
Option button, or radio button
Check box
Calendar control
Switchboard
4.1.4 Source Documents
collects input data
triggers or authorizes an input action
and provides a record of the original transaction
4.2 INPUT & OUTPUT DESIGN
4.2.1 Input Design & Technology Issues
quality of the output = quality of the input
garbage in, garbage out (GIGO)
4.2.2 Objectives of Input Design
to ensure the quality, accuracy, and timeliness of input data
Good input design requires attention to human factors as well as technology issues
4.2.4 Data Capture vs Data Entry
Data capture - service in which data is captured via tick or check boxes and other items where areas are filled in with simple lines or shapes in order to get the right answer.
usually multiple choice answers / yes or no questions
Data entry - manually entered text, copying exactly what the person who filled out the feedback form has written.
Input & Data Entry Method
Input methods should be cost-efficient, timely, and as simple as possible
Systems analysts study transactions and business operations to determine how and when data should enter the system
first decision is whether to use batch or online input methods
a. Batch Input
data entry is performed on a specified time schedule [ daily, weekly, monthly, or longer ]
b. Online Input
popular online input method = source data automation (combines online data entry and automated data capture using input devices such as RFID tags or magnetic data strips)
Advantages:
immediate validation
availability of data
Many large companies use a combination of source data automation and a powerful communication network to manage global operations instantly.
4.2.6 Input Mask & Validation Rules
Validation Rules
8 types of data validation rules:
Sequence check
Existence check
Data type check
Range check
Reasonableness check
Validity check
Combination check
Batch controls
Output Technology
a. Internet based information delivery
Instant messaging
This popular form of communication is another way for individuals and companies to communicate effectively over the Internet
b. Printed reports
c. Specialized forms of output
Portable, Web-connected devices that can run applications, handle multimedia output, and provide powerful, multipurpose communication for users
Retail point-of-sale terminals that handle computer-based credit card transactions, print receipts, and update inventory records
4.2.9 Types Of Reports
too little information = no value
too much information = confusing and difficult to understand
Detail reports
produces one or more lines of output for each record processed
detail line - each line of output printed
Exception reports
displays only those records that meet a specific condition or conditions
useful when the user wants information only on records that might require action, but does not need to know the details
Summary reports
Upper-level managers often want to see total figures and do not need supporting details
For the personnel manager, a summary report such as the one shown in Figure would be useful.
4.2.10 Design Report Principles
to produce a well designed report, the analyst must consider design features
Report headers and footers
Page headers and footers
Column heading alignment
Column spacing
Field order
Grouping detail lines
Repeating fields
Consistent design
4.2.12 Input & Output Controls & Security
A company must do everything in its power to protect its data
Output control & security
Output security protects privacy rights and shields the organization’s proprietary data from theft or unauthorized access.
First, limit the number of printed copies and use a tracking procedure to account for each copy.
All sensitive reports should be stored in secure areas.
Input control & security
Input control includes the necessary measures to ensure that input data is correct, complete, and secure.
You must focus on input control during every phase of input design, starting with source documents that promote data accuracy and quality.
Data security policies and procedures protect data from loss or damage, which is a vital goal in every organization