System Analysis and Design Week 11-12 Lecture | Chap 4: System Design

4.1.1 System Requirements Document The system requirements document, or Software Requirements Specification (SRS), contains the requirements for the new system, describes the alternatives that were considered, and makes a specific recommendation to management Like a contract Format and organize it so it is easy to read and use

4.1.2 Transition from Sys Analysis to Sys Design Completion of Systems Analysis Tasks Presentation to Management Summarize the primary viable alternatives Explain why the evaluation and selection team chose the recommended alternative Allow time for discussion and for questions and answers Obtain a final decision from management or agree on a timetable for the next step in the process

4.1.2 Transition from Sys Analysis to Sys Design Completion of Systems Analysis Tasks Presentation to Management Depending on management/ client decision, the development team next task and specific to systems analyst role will be one of the following Implement an outsourcing alternative Develop an in-house system Purchase or customize a software package Perform additional systems analysis work Stop all further work

4.1.2 Transition from Sys Analysis to Sys Design Completion of Systems Analysis Tasks Preparing for Systems Design Tasks It is essential to have an accurate and understandable system requirements document Logical and Physical Design The logical design defines the functions and features of the system and the relationships among its components The physical design of an information system is a plan for the actual implementation of the system

4.1.3: Systems Design Guidelines Overview A system is effective if it supports business requirements and meets user needs A system is reliable if it handles input errors, processing errors, hardware failures, or human mistakes A system is maintainable if it is flexible, scalable, and easily modified

4.1.3: Systems Design Guidelines Overview User Considerations Carefully consider any point where users receive output from, or provide input Anticipate future needs – eg: BYOD, Clound, 4G etc. Provide flexibility Parameter, default

4.1.3: Systems Design Guidelines Overview Data Considerations Enter data as soon as possible Verify data as it is entered Use automated methods of data entry whenever possible

4.1.3: Systems Design Guidelines Overview Data Considerations Control data entry access and report all entries or changes to critical values – audit trail Log every instance of data entry and changes Enter data once Avoid data duplication

4.1.3: Systems Design Guidelines Overview Architecture considerations Use a modular design Design modules that perform a single function are easier to understand, implement, and maintain

4.1.3: Systems Design Guidelines Design Trade-Offs Design goals often conflict with each other Most design trade-off decisions that you will face come down to the basic conflict of quality versus cost Avoid decisions that achieve short-term savings but might mean higher costs later

4.1.4 Software Development Trends Views from the IT Community Software quality will be more important than ever Project management will be a major focus of IT managers

4.1.4 Software Development Trends Views from the IT Community Growth in open-source software Developers will use more Web services Programmers will continue to use dynamic languages

To be Continue.. Week 12: 4.2 Understand User Interface Design

4.2 Understand User Interface Design Week 12 4.2 Understand User Interface Design Chapter Objective 4.2.1 Explain the concept of user interface design and human- computer interaction, including basic principles of user-centered design

What Is a User Interface? User interface (UI) Consists of all the hardware, software, screens, menus, functions, outputs, and features that affect two-way communications between the user and the computer ** Computers: PC, Tablet, Smart Phone, Wearables Devices eg: iwatch etc.

User Interface Design Evolution of the User Interface Process-control As information management evolved from centralized data processing to dynamic, enterprise-wide systems, the primary focus also shifted — from the IT department to the users themselves User-centered system Requires an understanding of human-computer interaction and user-centered design principles

User Interface Design Human-Computer Interaction Human-computer interaction (HCI) describes the relationship between computers and people who use them to perform their jobs Eg:Graphical user interface (GUI) Main objective is to create a user-friendly design that is easy to learn and use

User Interface Design Human-Computer Interaction

Principles of User-Centered Design 1. Understand the Business 2. Maximize Graphical Effectiveness 3. Think Like a User 4. Use Models and Prototypes 5. Focus on Usability 6. Invite Feedback 7. Document Everything

4.2 Understand User Interface Design Chapter Objective 4.2.2 List user interface design guidelines

Designing the User Interface 8 Basic Guidelines of User Interface Design 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 Very Famous Questions

Designing the User Interface: 8 Basic Guidelines of User Interface Design #1:Design a Transparent Interface Facilitate the system design objectives, rather than calling attention to the interface Create a design that is easy to learn and remember Design the interface to improve user efficiency and productivity Write commands, actions, and system responses that are consistent and predictable

Designing the User Interface: 8 Basic Guidelines of User Interface Design #1:Design a Transparent Interface Facilitate the system design objectives, rather than calling attention to the interface Create a design that is easy to learn and remember Design the interface to improve user efficiency and productivity Write commands, actions, and system responses that are consistent and predictable Home Icon Shortcut Top Menus

Designing the User Interface: 8 Basic Guidelines of User Interface Design #1:Design a Transparent Interface Facilitate the system design objectives, rather than calling attention to the interface Create a design that is easy to learn and remember Design the interface to improve user efficiency and productivity Write commands, actions, and system responses that are consistent and predictable

Designing the User Interface: 8 Basic Guidelines of User Interface Design #2:Create an Interface that Is Easy to Learn and Use Clearly label all controls, buttons, and icons Select only those images that users can understand easily, and provide on-screen instructions that are logical, concise, and clear Show all commands in a list of menu items Make it easy to navigate

Designing the User Interface: 8 Basic Guidelines of User Interface Design #3: Enhance User Productivity Organize tasks, commands, and functions in groups that resemble actual business operations Create alphabetical menu lists Provide shortcuts so experienced users can avoid multiple menu levels Use default values if the majority of values in a field are the same

Designing the User Interface: 8 Basic Guidelines of User Interface Design #4:Make It Easy for Users to Obtain Help or Correct Errors Ensure that Help is always available Provide user-selected Help and context- sensitive Help

Designing the User Interface: 8 Basic Guidelines of User Interface Design #5:Minimize Input Data Problems Create input masks Display event-driven messages and reminders Establish a list of predefined values that users can click to select Build in rules that enforce data integrity

Designing the User Interface: 8 Basic Guidelines of User Interface Design #6:Provide Feedback to Users Display messages at a logical place on the screen Alert users to lengthy processing times or delays Allow messages to remain on the screen long enough for users to read them Let the user know whether the task or operation was successful or not

Designing the User Interface: 8 Basic Guidelines of User Interface Design #7:Create an Attractive Layout and Design Use appropriate colors to highlight different areas of the screen Use special effects sparingly Use hyperlinks that allow users to jump to related topics Group related objects and information

Designing the User Interface: 8 Basic Guidelines of User Interface Design #8:Use Familiar Terms and Images Remember that users are accustomed to a pattern of red=stop, yellow=caution, and green=go Provide a keystroke alternative for each menu command Use familiar commands if possible Provide a Windows look and feel in your interface design if users are familiar with Windows-based applications

Lab Session Assignment (Presentation and Hardcopies Submission Wed 9/3/16 by 4pm) From below topics assigned to respective company, identify 8 Basic Guidelines of User Interface Design with minimum 8 examples of each of the rules. FireFly Online Ticket = A Technobiz Singapore Airlines Online Ticket =A Pandora Facebook =B K chrome Twitter = A Power On Book Depository(https://www.bookdepository.com/) = B =Mr. and Mrs Amazon Books (http://www.amazon.com/author-rank/Books-Featured- = Categories/books/51546011) = B genesys Booking.com = B Creat Agoda.com = A Hissa Lazada = A Globalnet Zalora = B Star

4.2 Understand User Interface Design Chapter Objective 4.2.3 Describe user interface components, including screen elements and controls

Designing the User Interface Add Control Features Menu bar Toolbar Command button Dialog box Text box Toggle button (allows the user to change a setting between two states.)

Designing the User Interface Add Control Features List box – scroll bar Drop-down list box Option button, or radio button Check box Calendar control Switchboard

4.3 Input Design 4.3.3 Data Entry Screens Guidelines Provide a way to leave the data entry screen at any time without entering the current record Provide users with an opportunity to confirm the accuracy of input data before entering it Provide a means for users to move among fields on the form Design the screen form layout to match the layout of the source document Allow users to add, change, delete, and view records Provide a method to allow users to search for specific information

4.2.4: Describe Source Documents and Forms Form layout Heading zone Control zone Instruction zone Body zone Totals zone Authorization zone Specific to Web Design

4.2.4 Source Documents and Forms Dr. Jakob Nielson believes that users scan a page, picking out individual words and sentences As a result, Web designers must use scannable text to capture and hold a user’s attention

4.3 Input Design The quality of the output is only as good as the quality of the input Garbage in, garbage out (GIGO) Objective of input design is to ensure the quality, accuracy, and timeliness of input data Good input design requires attention to human factors as well as technology issues

4.3 Input Design 4.3.3 Data Entry Screens Guidelines Restrict user access to screen locations where data is entered Provide a descriptive caption for every field, and show the user where to enter the data and the required or maximum field size Display a sample format if a user must enter values in a field in a specific format - separator Require an ending keystroke for every field

4.3 Input Design 4.3.3 Data Entry Screens Guidelines Do not require users to type leading zeroes for numeric fields Do not require users to type trailing zeroes for numbers that include decimals Display default values so operators can press the ENTER key to accept the suggested value Use a default value when a field value will be constant for successive records or throughout the data entry session Display a list of acceptable values for fields, and provide meaningful error messages

4.2 Understand User Interface Design Chapter Objective 4.2.4 Describe Source Documents

4.3 Input Design Explain Input Masks To Reduce Input Errors (4.3.6) Use input masks, which are templates or patterns that restrict data entry and prevent errors A mask can manipulate the input data and apply a specific format

4.3 Input Design 4.3.6 Explain Validation Rules To Reduce Input Errors: 8 types of data validation rules Sequence check Existence check Data type check Range check – limit check Reasonableness check Validity check – referential integrity Combination check Batch controls – hash totals

4.3 Input Design Input Technology: 4.3.5 Explain input and data entry methods for Batch and Online Output Batch input (4.3.5) Data entry usually performed on specified time schedule Eg: Every 4 hrs, 12 hrs, weekly, monthly Online input (4.3.5) Online data entry Source data automation RFID tags or Magnetic data strips

4.3 Input Design Input Technology (4.3.1 Technology Issues) Tradeoffs Unless source data automation is used, manual data entry is slower and more expensive than batch input because it is performed at the time the transaction occurs and often done when computer demand is at its highest The decision to use batch or online input depends on business requirements

4.3 Input Design Input Volume Reduction Guidelines will help reduce input volume Input necessary data only Do not input data that the user can retrieve from system files or calculate from other data Do not input constant data Use codes

4.3 Output Design Before designing output, ask yourself several questions: What is the purpose of the output? Who wants the information, why is it needed, and how will it be used? What specific information will be included? Will the output be printed, viewed on-screen, or both? What type of device will the output go to?

4.3 Output Design Before designing output, ask yourself several questions: When will the information be provided, and how often must it be updated? Do security or confidentiality issues exist? Your answers will affect your output design strategies

4.3 Output Design Overview of Report Design Few companies have been able to eliminate printed output totally Eg: Airasia online check in Turnaround documents Reports must be easy to read and well organized Database programs include a variety of report design tools

4.3 Output Design Identify Types of Reports (4.3.9) Detail reports Exception reports Summary reports ( Also known as Summary Report)

4.3 Output Design Details Report Examples

4.3 Output Design Explains various output types and the technology ( 4.3.8) Internet-based information delivery (4.3.8a) Webcast Email Blogs Instant Messaging Printed Report (4.3.8b) Eg: Printed CPA and CGPA of each semester result of student result Specialized form of output (4.3.8c) Eg: 3D printers

4.3 Output Design Output Technology (4.3.8) ( 4.3.8) Output Technology (4.3.8) Digital audio, images, and video Podcasts a form of digital media that consists of an episodic series of audio, video, digital radio Automated facsimile systems Faxback systems Computer output microfilm (COM) // Old Technology Creating microfilm or microfiche from the computer. For approximately three decades before the turn of the century, COM machines were used to take print-image output from the computer either online or via tape or disk and create a film image of each page.

4.3 Output Design Output Technology Specialized Forms of Output An incredibly diverse marketplace requires many forms of specialized output and devices Portable, Web-connected devices Retail point-of-sale (POS) terminals Automatic teller machines (ATMs) Special-purpose printers

4.3.12 Security and Control Issues Output Control and Security Output security The IT department is responsible for output control and security measures Diskless workstation Port protector

4.3.12 Security and Control Issues Input Security and Control Input Control Every piece of information should be traceable back to the input data Audit trail Data security Records retention policy Encrypted – encryption

Entity-Relationship Diagrams Types of Relationships (4.4.1) Three types of relationships can exist between entities One-to-one relationship (1:1) One-to-many relationship (1:M) Many-to-many relationship (M:N)

Entity-Relationship Diagrams Define Cardinality (4.4.2) & Use Cardinality Notation (4.4.3) Cardinality notation the number of elements in a set or other grouping, as a property of that grouping. In database design, the cardinalityof one data table with respect to another is a critical aspect. The relationship of one to the other must be precise and exact between each other in order to explain how each table links together. When developer understand database elements and their relationships, table design can be start.

Entity-Relationship Diagrams Cardinality notation Example: Consider a database designed to keep track of hospital records. Such a database could have many tables like: a doctor table with information about physicians; a patient table for medical subjects undergoing treatment; and a department table with an entry for each division of a hospital. In that model: There is a many-to-many relationship between the records in the doctor table and records in the patient table because doctors have many patients, and a patient could have several doctors; There is a one-to-many relationship between the department table and the doctor table because each doctor may work for only one department, but one department could have many doctors.

Entity-Relationship Diagrams Drawing an ERD (4.4.4) The first step is to list the entities that you identified during the fact-finding process and to consider the nature of the relationships that link them A popular method is to represent entities as rectangles and relationships as diamond shapes

Normalization (4.4.5) Standard Notation Format Designing tables is easier if you use a standard notation format to show a table’s structure, fields, and primary key Example: NAME (FIELD 1, FIELD 2, FIELD 3)

Explain The Concept of Normalization (4.4.5) Repeating Groups and Unnormalized Design Repeating groups Often occur in manual documents prepared by users Unnormalized Enclose the repeating group of fields within a second set of parentheses

Normalization (4.4.5) First Normal Form A table is in first normal form (1NF) if it does not contain a repeating group To convert, you must expand the table’s primary key to include the primary key of the repeating group

Normalization (4.4.5) Second Normal Form A table design is in second normal form (2NF) if it is in 1NF and if all fields that are not part of the primary key are functionally dependent on the entire primary key A standard process exists for converting a table from 1NF to 2NF The objective is to break the original table into two or more new tables and reassign the fields so that each non-key field will depend on the entire primary key in its table

Normalization (4.4.5) Third Normal Form 3NF design avoids redundancy and data integrity problems that still can exist in 2NF designs A table design is in third normal form (3NF) if it is in 2NF and if no nonkey field is dependent on another nonkey field To convert the table to 3NF, you must remove all fields from the 2NF table that depend on another nonkey field and place them in a new table that uses the nonkey field as a primary key

Well Done! End of Chapter 4