SAD: Ch 10 to 16

10C H A P T E R

FEASIBILITY ANALYSIS AND THE SYSTEM PROPOSAL

Feasibility Analysis

Feasibility – the measure of how beneficial or practical an information system will be to an organization.

– Just like any kinds of business projects…– Cost/benefit analysis…– Feasibility analysis: the process by which feasibility is

measured.

Any feasibility should be measured throughout the life cycle (so call “Creeping Commitment” approach)

Feasibility Checkpoints During Systems Analysis

Four Tests For Feasibility

Operational feasibility- A measure of how well a solution will work or be accepted in an

organization, including how the users and managers feel about the problems and solutions

Technical feasibility- A measure of the practicality of a technical solution and the availability

of technical resources and expertise.

Schedule feasibility- A measure of how reasonable the project schedule and deadline is.

Economic feasibility (the most important…)– A measure of the cost-effectiveness of a project or solution.

– Whether a solution will pay for itself or how profitable a solution will be

Cost-Benefit Analysis Techniques

Related with Economic feasibility…– Learn details from finance courses

• Three Popular Techniques – Payback Analysis– Return On Investment– Net Present Value

• Tangible vs. intangible benefits (pp. 409 and 410)

Candidate Systems Matrix

Candidate Systems Matrix – a tool used to document similarities and differences between candidate systems.

– Related with decision analysis phase– pp. 416: figure 10-7

Feasibility Analysis Matrix – a tool used to rank candidate systems.

– pp. 418: 10-9

12C H A P T E R

SYSTEM DESIGN

Focus of Ch 12

• Refer to the methodology article • And Ch 05

System Design Tasks For Integrating Commercial SW (Buy)

• Research technical criteria and options• Solicit proposals (or quotes) from vendors

– Will vendors be able to provide service continuously? (survive)

– Quality? (different than buy a group automobiles for an organization)

• Validate vendor claims and performance• Evaluate and rank vendor proposals• Award (or let) contract and debrief vendors

13C H A P T E R

APPLICATION ARCHITECTURE AND MODELING

Focus of Ch 13

• Refer to the MIS 440: Network • And each model

Distributed vs. Centralized Systems

Distributed system – a system in which components are distributed across multiple locations and computer networks.

Centralized systems – a system in which all components are hosted by a central, multi-user computer.

• Cost– productivity

• Security• Strategic plan

– Empowerment of each Dept. or Division

Why the Trend Toward Distributed Systems?

• Modern businesses are already decentralized (distributed).

• Distributed computing moves information and services closer to the customers and users who need them.

• Distributed computing consolidates the power of personal computers across the enterprise.

• Distributed computing solutions are in general more user-friendly because they use the PC as the user interface processor.

• Personal computers and network servers are less expensive than mainframe computers – Though total cost of ownership is at least as expensive

15C H A P T E R

OUTPUT DESIGN AND PROTOTYPING

Output Design with an Old Style Printer Spacing Chart

Output Design with a Modern CASE Tool

Output Design with a Report Writer Tool

Output Design with a Report Writer Tool (continued)

Output Design Guidelines

1. Outputs should be simple to read and interpret.– Include a title.

– Date and time stamp.

– Include sections and headings to segment information.

– Clearly label all fields and columns.

– Include legends for all abbreviations.

– Include only required information. Online provide methods to expand and contract information.

– Report information in format that does not have to be manually edited.

– Information should be balanced across the page or screen.

– Provide for easy navigation.

– Avoid computer jargon and error messages.

Output Design Guidelines

2. The timing of outputs is important.• This can affect how the output is designed an implemented

3. The distribution of (or access to) outputs must be sufficient to assist all relevant users.

• The choice of implementation method affects distribution

4. Outputs must be acceptable to the system users who will receive them.

• Systems analyst must understand how the recipient plans to use the output

See page 599 – 607…

16C H A P T E R

INPUT DESIGN AND PROTOTYPING

Input Implementation Methods

• Keyboard• Mouse• Touch Screen• Point-of-sale terminals• Sound and speech• Automatic data capture

– Optical mark recognition (OMR)

• Bar codes– Optical character recognition (OCR)

– Magnetic Ink

– Electromagnetic transmission

– Smart cards

– Biometric

Automatic Identification: Bar Codes

Good Flow in a Form

Bad Flow in a Form

Input Design

Common GUI Controls (Windows and Web)

• Text boxes• Radio

buttons• Check boxes• List boxes• Drop down

lists• Combination

boxes• Spin boxes• Buttons

Common GUI Controls Uses• Text boxes– When the input data values are unlimited in scope

• Radio buttons– When data has limited predefined set of mutually exclusive values

• Check boxes– When value set consists of a simple yes or no value

• List boxes– When data has a large number of possible values

• Drop down lists– When data has large number of possible values and screen space is too

limited for a list box• Combination boxes

– When need to provide the user with option of selecting a value from a list or typing a value that may or may not appear in the list

• Spin boxes– When need to navigate through a small set of choices or directly typing a

data value

Advanced Controls (mostly Windows interfaces)

• Drop down calendars

• Slider edit controls

• Masked edit controls

• Ellipsis controls

• Alternate numerical spinners

• Check list boxes

• Check tree boxes

Advanced Controls (mostly Windows interfaces)

Automated Tools for Input Design and Prototyping

• Old Tools– Record Layout Charts– Display Layout Charts

• Newer Prototyping Tools– Microsoft Access– CASE Tools– Visual Basic– Excel– Visio

Input Prototype for Video Title Maintenance

Input Prototype for Member Order

Input Prototype for Member Shopping

Input Prototype for Web Shopping Cart

Input Prototype for Web Interface