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Objectives. Explain the differences between logical and physical designDiscuss the objectives of systems design and provide guidelines for good designList and describe the major activities of the systems design phaseDesign and use appropriate codes in systems design and development. Objectives. Provide examples of types of output, including new technology-based methods of information deliveryDescribe the classifications of output reports and explain the differences among themDesign effectiv9440
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1. CIS 302 Introduction to Systems Analysis and Design
Output Design
2. Objectives Explain the differences between logical and physical design
Discuss the objectives of systems design and provide guidelines for good design
List and describe the major activities of the systems design phase
Design and use appropriate codes in systems design and development
3. Objectives Provide examples of types of output, including new technology-based methods of information delivery
Describe the classifications of output reports and explain the differences among them
Design effective printed reports that will meet user requirements
4. Objectives Design screen reports that are easy to understand and use
Explain output control concepts and methods
5. Logical design defines necessary system requirements and called an essential model
Logical design specifies what must take place, not how it will be accomplished
Physical design concerns how the system will be implemented
Physical design describes specific components and system specifications Systems Design Overview
6. The relationship between analysis and design
Logical and physical design are related closely
Analysis should be completed before design
Developers do not return from design to analysis work except in limited circumstances
An important fact is overlooked
Users have significant new needs
Legal/governmental requirements change
Unforeseen design issues or problems arise Systems Design Overview
7. Systems design activities
All system components are related closely
Must understand the entire logical design Systems Design Overview
8. Systems design steps
Review the system requirements
Design the system
Output
Input
Files and databases
System architecture
Present the systems design Systems Design Overview
9. General Guidelines for Systems Design Characteristics of a well-designed system
Effective
Satisfies defined requirements
Accepted by users
Reliable
Adequately handles errors (input, processing, hardware, or human mistakes)
Maintainable
Well-designed and flexible
Future modifications considered
10. General Guidelines for Systems Design Design suggestions
Three categories of considerations
User considerations
Data considerations
Processing considerations
11. General Guidelines for Systems Design User considerations
Make the system user-friendly
Consider where users receive output, or provide input to the system
Anticipate future needs
Users
Information system
Organization
12. General Guidelines for Systems Design Data considerations
Enter data where and when it occurs
Verify data where it is input
Use automated data-entry methods
Control access for data entry
Report all entries or changes to critical values
Enter data into a system only once
Avoid data duplication
13. General Guidelines for SystemsDesign Processing considerations
Use a modular (structured) design
Design modules that perform a single function
14. TRADEOFF Good design: the flexibility issue
Hardcoded (fixed) values are inflexible
Users needs constantly change
Variable parameters can provide flexibility
Default values can be combined with user-defined parameters
15. A KEY QUESTION What if users could design most of their own reports without IS assistance?
Would they request as many reports or the same types of reports?
What are the pros and cons of giving users total control over output?
16. General Guidelines for Systems Design Design tradeoffs
Design goals often conflict with each other
Easier use might create more complex programming requirements
More flexibility might increase maintenance needed
Meeting one users requirements might make it harder to satisfy anothers needs
A major issue is quality versus cost
17. Designing and Using Codes A code is a set of letters or numbers that represents an item of data
Codes serve many useful purposes
Save storage space and costs
Reduce data transmission time
Decrease data entry time
Can reveal or conceal information
Can reduce input errors
18. Designing and Using Codes Types of coding
Sequence codes
Block sequence codes
Classification codes
Alphabetic codes
Mnemonic codes
19. Designing and Using Codes Types of Coding
Sequence codes
Block sequence codes
Classification codes
Alphabetic codes
Mnemonic codes
Significant digit codes
20. Designing and Using Codes Types of coding
Sequence codes
Block sequence codes
Classification codes
Alphabetic codes
Mnemonic codes
Significant digit codes
Derivation codes
21. Designing and Using Codes Types of coding
Sequence codes
Block sequence codes
Classification codes
Alphabetic codes
Mnemonic codes
Significant digit codes
Derivation codes
Cipher codes
Action codes
Self-checking codes
22. Designing and Using Codes Developing a code
Keep codes concise
Allow for expansion
Keep codes stable
Makes codes unique
Use sortable codes
Avoid confusing codes
Make codes meaningful
Use a code for a single purpose
Keep codes consistent
23. Introduction to Output Design Users judge a system based on how well the output helps them perform their jobs
Output must be
Useful
Accurate
Understandable
Timely
24. Introduction to Output Design Checklist for output design
Design process depends on
What is the purpose of the output?
Who or what wants this information, why is it needed, and how will it be used?
What information will be included?
What format should be used?
When will information be provided, and how often must it be updated?
Will simultaneous user access be required?
Are security or confidentiality issues involved that need to be considered?
25. Types of Output and InformationDelivery Technology affects how people communicate and obtain information
Printers
Screens
Plotters
Audio output
E-mail
Links to Web pages
Automated facsimile system
Computer output microfilm (COM)
Other specialized devices
26. Types of Output and InformationDelivery Printed output
Impact printers
Laser printers
Turnaround documents
Advantages/disadvantages of printed output
Many people prefer to work with paper
Paper is portable
Printed output is expensive to purchase, print, store, and dispose of
Printed output is outdated quickly
27. Types of Output and Information Delivery Screen output
The screen is the most familiar output device
Monitor
CRT (cathode ray tube)
LCD (liquid crystal display)
VDT (video display terminal)
Graphical output allows various special effects and user-friendly features
Screen output reflects immediate data changes
28. Types of Output and Information Delivery Other types of information delivery
Audio output
29. Types of Output and Information Delivery Other types of information delivery
Audio output
Automated facsimile and faxback systems
E-mail
Links to Web pages
Specialized forms of output
30. Designing Printed Reports Reports can be classified by content
Detail reports
Exception reports
Summary reports
Reports also can be classified by distribution
Internal reports
External reports
31. Designing Printed Reports Detail reports
Provide the most information
At least one line of output is produced for each record processed
Detail reports can be quite lengthy
32. Designing Printed Reports Detail reports
Provide the most information
At least one line of output is produced for each record processed
Detail reports can be quite lengthy
Control-break reports
Use a control field
Must be sorted on the control field before printing
A control break occurs when the control field value changes
33. Designing Printed Reports Exception reports
Show only records that meet a specific condition
Useful when particular information is required
Special parameter queries can be used to select only the records that meet specified conditions
34. Designing Printed Reports Summary reports
Show only subtotals and totals
Useful for upper-level managers who do not require extensive detail
35. Designing Printed Reports Internal reports
Distributed within the organization
Usually printed on stock paper
Blank, single ply, standard size
Less expensive
Can be used for many types of reports
36. Designing Printed Reports External reports
Distributed outside the organization
Might include statements, invoices, or paychecks
Usually printed on special forms
More expensive than stock paper
Paper must be changed for each report printing job
Multi-part forms must be separated or decollated
37. Designing Printed Reports External reports
Distributed outside the organization
Might include statements, invoices, or paychecks
Usually printed on special forms
More expensive than stock paper
Paper must be changed for each report printing job
Multi-part forms must be separated or decollated
Special forms can use preprinted graphics and logos
38. Designing Printed Reports Usually printed on special forms
More expensive than stock paper
Paper must be changed for each report printing job
Multi-part forms must be separated or decollated
Special forms can use preprinted graphics and logos
Special applications, such as checks, require special forms
39. Designing Printed Reports Designing the report
Most reports use graphical design
Choice of typefaces and scalable fonts
More design flexibility
Some reports are character-based
Printed on high-speed impact printers
Require printer spacing charts for layout and design
40. Designing Printed Reports Stock paper reports
Page heading lines
Column heading lines
Column heading alignment
41. Designing Printed Reports Stock paper reports
Page heading lines
Column heading lines
Column heading alignment
Spacing between columns
Order of data items on detail lines
42. Designing Printed Reports Stock paper reports
Page heading lines
Column heading lines
Column heading alignment
Spacing between columns
Order of data items on detail lines
Grouping detail lines
43. Designing Printed Reports Stock paper reports
Page heading lines
Column heading lines
Column heading alignment
Spacing between columns
Order of data items on detail lines
Grouping detail lines
Report footing
Improving a report design
Documenting a report design
44. Designing Printed Reports Stock paper reports
Page heading lines
Column heading lines
Column heading alignment
Spacing between columns
Order of data items on detail lines
Grouping detail lines
Report footing
Improving a report design
Documenting a report design
Design consistency
45. TRADEOFF What can you do when there are not enough print positions on the page?
Several possible options
Abbreviate the column headings, with legend below
Print subtotals and totals
46. TRADEOFF What can you do when there are not enough print positions on the page?
Several possible options
Abbreviate the column headings, with legend below
Print subtotals and totals
Alternate odd/even months
47. TRADEOFF What can you do when there are not enough print positions on the page?
Several possible options
Abbreviate the column headings, with legend below
Print subtotals and totals
Alternate odd/even months
Split the report into versions
48. TRADEOFF What can you do when there are not enough print positions on the page?
Several possible options
Abbreviate the column headings, with legend below
Print subtotals and totals
Alternate odd/even months
Split the report into versions
Use stacked headings
49. TRADEOFF Several possible options
Abbreviate the column headings, with legend below
Print subtotals and totals
Alternate odd/even months
Split the report into versions
Use stacked headings
Use two detail lines
50. A KEY QUESTION The problem: users receive many reports, but do not seem to read them
The solution: a procedure that requires users to review and justify their information needs
The key question: Jan Lauten needs to recommend a procedure to her boss, Lynn Jennings. What advice can you give to Jan?
51. Designing Printed Reports Special form reports
Can use printer spacing charts to design
Placement of preprinted graphics can be indicated
Functional and aesthetic design principles are important
Field labels should be short but descriptive
Avoid nonstandard abbreviations
Order and placement of printed fields should be logical
Totals should be identified clearly
52. Designing Printed Reports Report volume and time calculations
Accurate estimates are necessary to
Determine whether printing capacity is adequate
Achieve efficient printing operations
Ensure timely delivery of finished reports
Provide reliable forecasts of paper and storage needs
53. Designing Printed Reports Report volume and time calculations
Factors to consider
Types of printers
Print volume calculations
Print-time calculations
54. Designing Screen Output Major advantage is timeliness
Screen output can be produced when and where needed
55. Designing Screen Output Screen design considerations
Many print design principles apply to screens
Screens also need instructions and messages
Users require immediate Help and feedback
Character-based screens
Screen locations are plotted using columns and lines
Use screen display layout forms
Messages typically on top or bottom line
Graphical screens
Screen locations are plotted in inches or other units
More flexible designs are possible
56. Designing Screen Output Character output
High-resolution monitors allow more flexibility
Display must be clear and easy to read
Fonts and typefaces must be chosen carefully
57. Designing Screen Output Character output
High-resolution monitors allow more flexibility
Display must be clear and easy to read
Fonts and typefaces must be chosen carefully
Screens vs. printed output
Information might need redesign for smaller screen
Multiple screens might be necessary
Columnar or tabular designs are possible
58. Designing Screen Output Graphical output
Graphical displays can be very effective
Many formats are possible
59. Designing Screen Output Graphical output
Graphical displays can be very effective
Many formats are possible
Pie charts
Maps
Bar charts
Area charts
Scatter diagrams
Use descriptive titles, label each axis, and include a legend
60. Designing Screen Output Special effects
Character-based systems can use special effects
High brightness
Blinking
Reverse video
Use of different colors for emphasis
Graphical environment provides options
Command buttons
Boxes and borders
Unlimited use of color
Custom menus, icons, and multiple windows
61. Designing Other Outputs Output to tapes and disks
In an integrated environment, data transfer is handled by interactive network design
In other cases, data transfer uses tapes or disks
Output from one program can be input to another
An output file format is a data structure that can be understood by another program or system
Tape or disk output design must calculate file volume
62. Designing Other Outputs Other output media
Format and contents depend on the output device and its requirements
Various output options exist
Plotter output
Series of commands is formatted for the specific plotter being used
Computer output microfilm (COM)
Output is recorded as images on roll or sheet film
Data scanned/stored in digital form
63. Output Control Output integrity
Ensure output is correct, complete, & secure
Include appropriate titles and dates on reports
Number pages consecutively
Identify the end of each report
Print/reconcile control totals/record counts
Review error reports for possible causes
Create error file to flag uncorrected/reentered records
64. Output Control Output security
Protects privacy rights and proprietary data
Important tasks to carry out
Control the number of report copies
Distribute reports only to authorized users
Store sensitive reports in secure areas
Label all pages of confidential reports
Burn/shred sensitive reports & other output
Inventory blank checks regularly
Store signature forms securely
65. Automated Design Tools Report generators
Included in CASE tools & database programs
Powerful, easy-to-use features
Enter constant information (titles/headings)
Specify a print position for each item
Use field sizes from data dictionary to create a design
Produce a report definition
Creates program code that can be modified
66. Automated Design Tools Screen generators
Similar to report generators
Create displays using onscreen layout tools
67. Automated Design Tools Completing the report and screen designs
Ensure consistency with data dictionary
Automate routine design tasks
Produces rapid results
Does not guarantee good design
Still must know and apply effective design to produce reports and screens that satisfy user requirements