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What is meant by change control? How is it helpful to the programming effort?

- Change control is defined as the action of coordinating a program as it changes through construction. It is helpful to the programming effort because coordinating a changing program requires well organized project teams that set up the following three areas: development, testing, and production. Files, data, and programs are separated on the basis of their status of completion into these three areas. Files can be accessed and built in the development area by programmers, copied onto the testing area when they are finished, and then copied into the production area when these are tested and ready to support the new system. If programs don't pass a test, they are sent back to the development area, but once they pass the test, these are passed onto where the final system will be. Change control also keeps track of what programs are being changed and by who, logging them onto a program log.

What is meant by the characteristic of module cohesion? What is its role in structure chart quality?

- Cohesion refers to how well the lines of code within each structure chart relate to each other. Each module should perform one and only one task, which makes it highly cohesive. These are simple to understand and build because they perform just one function very efficiently. Some examples of cohesion are functional cohesion (all elements of the module contribute to performing a single task), temporal cohesion (functions within a module may not have much in common other than being invoked at the same time), and coincidental cohesion (no apparent relationship among a module's function). In order to separate the a function of one module to its own, one needs to perform a process known as factoring.

Why is consistency in design important? Why can too much consistency cause problems?

- Consistency means that all parts of the same system work in the same way. This enables the users to predict what will happen because a function in one part of the system works the same way in other parts of the system. Users will be confident as they work with different parts of the system if they can predict the behavior of functions throughout the system. The problem with too much consistency is that sometimes the users don't differentiate forms or reports that look very similar to each other, and inadvertently use the wrong one. So, in these cases, there should be enough unique characteristics to distinguish each form and report from the others.

Why is content awareness important?

- Content awareness means that the interface makes the user aware of the information delivered through the interface with the least amount of user effort. This is important because if the user is constantly aware of where he is and what he is seeing, he will find the system much easier to use and his satisfaction will be high

Describe the types of cultural and political requirements and how they may influence architecture design.

- Cultural and Political requirements include: Multilingual - Does the environment require the system to operate in more than one language? Customization - Are there features that can be customized according to different national cultures? Making Unstated Norms Explicit - Are there assumptions that may be ambiguous in different national cultures? If so, they need to be explicitly stated. Legal - are there national and/or international legal issues that need to be addressed?

What is the purpose of creating a logical process model and then a physical process model?

- During analysis, system analysts identify processes and data flows that support the functional requirements of a new system. Both of these are described on the logical Data Flow Diagram for the to-be system. While this doesn't require any indication of how the system will be implemented when the information system is built, the physical process models does since these are created to show implementation details and explanation of how the final system will work. It is important to create the logical process model first to know what the new system will do before designing the physical process model which explains what the system does.

Why is using a top-down modular approach useful in program design?

- In order to create a maintainable system that is modular and flexible, analysts can design programs in a top-down modular approach. What this approach does is narrow down specific information from a general context to logical pieces, adding detail to each of these pieces. Program design benefits from this approach with analyst creating a high-level diagram that shows the various components of a program, how they should be organized, and how they interrelate. This diagram, known as structure chart, illustrates the organization and interactions of the different pieces of code within the program to analysts and programmers so that it can be developed by programmers working independently.

Why is it important to perform an interface evaluation before the system is built?

- Interface evaluations are done to understand how to improve the interface design. These evaluations should be done before the system is built in order to identify any major design problems and correct them before time and cost have been spent programming a weak design. There are four type of evaluations: heuristic evaluations (members of the project team examining the interface to a set of principles for interface design, identifying improvements); walk-through evaluations (users being part of a meeting that will have them operating the system to identify improvements); interactive evaluations (users working with the HTML or language prototype with members of the project team individually); and formal usability testing (users testing the language prototypes on a lab that records the users using the system without help of the project team after initial instructions).

Why are interface standards important?

- Interface standards help define the basic, common design elements in the system. These standards help ensure consistency throughout the system.

Under what circumstances would you use a drop-down menu versus a tab menu?

- Menus are the most common type of navigation systems. They present the user with a list of choices that can be selected. Two type of menus are the drop-down menu, which is a menu that drops down immediately below another menu and disappears after one use, and the tab menu, which is a multipage menu with one tab for each page that pops up and floats over the screen until they are closed. The former should be used when in need of a second-level menu accessed from the menu bar (which are always on screen), while the latter should be used when the ser needs to change several settings or perform several related commands.

Describe the purpose of program specifications.

- Once the analyst has communicated the big picture of how the program should be put together, they then describe the individual modules in detail so that programmers can begin writing code. Modules on the structure chart are described by program specifications, which are documents that include instructions regarding how to program pieces of code. Project team members write one for each module on the structure chart and pass them along to programmers who then write the code in the implementation phase of the project. They must be clear and easy to understand, pinpointing design problems that exist in the structure chart.

Describe the major phases in the systems development life cycle (SDLC).

- Planning: understand why an IS should be built and determine how project team will go about building it. - Two steps: 1. Project initiation: systems business value to the organization is identified. 2. Project management: workplan, staffs project, puts techniques in place to help control and direct project thought entire SDLC Focus: why build the system? How to structure the project? Primary outputs: • System request with feasibility study • Project Plan - Analysis: answers questions of who will use the system, what the system will do, where and when it will be used. - Three Steps: 1. Analysis strategy: guides project team's efforts 2. Requirements gathering: through techniques such as interviews, group workshops, or questionnaires 3. System proposal: analyses, system concept, requirements, and models are combined into a document. Focus: Who, what, where and when for this system? Primary output: • System proposal - Design: how the system will operate in terms of hardware, software, and network infrastructure that will be in place; user interface, forms and reports that will be used; and the specific programs, databases, and files that will be needed. - 4 steps: 1. Design strategy 2. Architecture design (hardware, software, network infrastructure) 3. Database and file specifications 4. Program design Focus: How will this system work? Primary output: System specification - Implementation: system is built (or purchased) - 3 steps: 1. Construction 2. Installation 3. Support plan Focus: Delivery and support of completed system Primary Output • Installed System

Describe the major elements and issues with waterfall development.

- Project team proceeds sequentially from one phase to the next. -Moves from phase to phase - emphasis on deliverables from one phase flowing into the next phase

Why do we prototype the user interface design?

- Prototyping helps the users and programmers understand how the system will perform. Prototypes can be very useful in helping the users conceptualize how they will actually work with the system, and prototypes can help identify problems or misconceptions in the interface before it is actually implemented.

What is the purpose of the structure chart in program design?

- Structure chart is an important technique that helps the analyst design the program for the new system. It shows all the components of code that must be included in a program at a high level, arranged in a hierarchical format that implies sequence, selection, and iteration. Tended to be read from top to bottom, left to right, they are numbered by a hierarchical numbering scheme in which lower levels have an additional level of numbering. They have been used to create transaction-based timeframe applications with many lines of code that must be monitored. They can be helpful in the program design since it can be helpful in the building of many types of systems because they emphasize structure and reusability.

Compare and contrast the roles of a systems analyst, business analyst, and infrastructure analyst.

- System analyst- focuses on the IS issues surrounding the system. Develops ideas and suggestions for ways the IT can support and improve business processes, helps design new business processes supported by IT, designs the new information system and ensures that all IS standards are maintained. Skills: Analysis, design and programming - Business analyst- focuses on the business issues surrounding the system. Helps identify the business value that the system will create, develops ideas for improving the business processes, and helps design new business processes and policies. Skills: business training and experience, plus knowledge of analysis and design. - Infrastructure analyst - focuses on technical issues surrounding the ways the system will interact with the organizations technical infrastructure (hardware, software, networks, and databases). Ensures that the new IS conforms to organizational standards and helps to identify infrastructure changes that will be needed to support the system.

What is the purpose of the hardware and software specification?

- The hardware and software specification is a document that details the requirements of the new system in terms of operating system, hardware, software, and network devices.

How can different parts of the interface be consistent?

-. The navigation controls can be consistent, using the same icon or command to trigger an action throughout the system. Terminology can be consistent throughout the interface. The content portion of the screen that contains forms and reports should also present consistently designed reports and forms. Messages and information in the status area should be specified consistently throughout the system.

Explain the mobile application architecture.

-Are more convenient. Developing apps for mobile devices requires a different skill set than for other computing devices. However, the system architect must still decide how much of the presentation logic, the business logic, and data access logic will reside on the mobile device, and how much will reside on server devices. If the app requires local processing using the mobile devices resources, such as the camera or GPS, and is only occasionally connected to the server, it should be created as a rich client. A rich client has the business and data access logic included on the device along with the presentation logic. When the application can rely on the availability of server processing and will always be connected, a thin web-based client can be developed. Native apps are written to run on a specific device with a specific operating system. Are written in the device's native code (Objective C for Apple; Java for Android devices) and provide the richest user experience and can take full advantage of the device's resources. Usually cross-platform apps must be "tweaked" for each device on which it will be deployed. Mobile web apps are platform independent are often developed using HTML5, must be used on a device with a web browser.

Explain the client-server architecture

-Balance the processing between client and devices and one or more server devices. -Generally, clients are responsible for the presentation logic and the server(s) are responsible for the data access logic and data storage. Application logic location varies depending on the C-S configuration chosen. -They're scalable, can support different types of clients and servers through middleware. The presentation logic, application logic and data processing logic can be independent. -If a server fails, only the applications requiring that server are affected - highly reliable. -two-tiered, three-tiered, and n-tiered client server architecture exist PROS: modular business logic components are shareable across applications. -Separating the processing among multiple servers makes it possible to balance the server loads efficiently. - CONS: the higher tiers place a higher load on the network. Makes it more difficult to implement since the servers must communicate effectively.

List and describe the three primary hardware components of a system.

-Client Computers: input-output devices employed by users (ex. PC's, laptops, handheld and mobile devices, smart phones) -Servers: larger multi-user computers used to store software and data -Network: Connects the computers.

List and describe the four primary functional components of a software application.

-Data Storage -Storing Data -Data Access Logic - The processing required to access stored data -Application logic- the logic documented in the DFD's use cases, and functional requirements -Presentation logic: the display of information to the user and the acceptance of the user's commands.

Describe the types of operational requirements and how they may influence architecture design.

-Operational requirements specify the operating environments in which the system must perform and how those may change over time. This usually refers to operating systems, system software, and information systems with which the system must interact, but will on occasion also include the physical environment if the environment is important to the application (ex. In a noisy factory where no audible alerts can be heard)

Explain the server-based architecture.

-These are older architectures in which the server (often a mainframe computer) performs all of the application functions. The clients, then called "dumb" terminals, enabled users to send and receive messages to and from the server computer. The clients merely captured keystrokes and sent them to the server for processing, and accepted instructions from the server on what to display. Is a very simple architecture. But the fundamental problem was that the server processed all of the work in the system and could become overloaded as more users are added. So the servers would need to be upgraded frequently which is an expensive proposition.

What is the primary goal of unit testing?

-To ensure that the module or program performs its functions as defined in the program specification. Unit testing is performed after the programmer has developed and tested the code and believes it to be error free. The tests are based strictly on the program specification and may discover errors resulting from the programmer's misinterpretation of the specifications.

Describe the elements of the use case's basic information section.

1) Identify the use cases: Start a use case report form for each use case. 2) Identify the major steps within each use case: For each use case, fill major steps needed for task. 3) Identify elements within steps: For each step, identify inputs and outputs. 4) Confirm the use case: For each case, validate its correct and complete.

Describe the five major steps in conducting JAD sessions.

1) Selecting Participants: same as selecting interview participants select on the basis of information they can contribute. 2) Designing the JAD session: can run from half a day to several weeks, requires collection of information from users, and avoid close-ended questions. 3) Prepare for the JAD sessions: JAD's lead to be more in-depth, therefore more preparation is needed. It is important for participants to know what is expected of them. 4) Conducting the JAD session: follow formal agenda, ground rules, respect others opinions, accepting disagreement, and ensure only one talks at a time. 5) Post-JAD Follow-Up: prepare and circulated among session attendees. Post-session report goes over what was done.

What is a data model? What is an Entity Relationship Diagram (ERD)? Explain each in a bit of detail.

A data model is a formal way of representing the data that are used and created by a business system. It illustrates people, places, or things about which information is captured and how they are related to each other. When this model is developed, it evolves from being more conceptual to more detailed. This happens because of an ERD, which is a picture that shows the information that has been created, stored, and used by a business system. Similar kinds of information are listed together and placed inside boxes called entities, and lines are drawn between them to represent relationships among data.

Compare and contrast pilot conversion, phased conversion, and simultaneous conversion.

A pilot conversion selects one or more locations to be converted first as a part of a pilot test. If the conversion at the pilot location is successful, then the system is installed at the remaining locations. A phased conversion is preferable when you need to introduce a system to different locations and in phases. With Phased conversion, a first set of locations is converted, then the second set, then a third set, and so on, until all locations are converted. If it is necessary to convert all locations at the same time, suggesting the need for simultaneous conversion. The new system is installed at all locations at once, thus eliminating the problem of having different organizational units using different systems.

What is a primary key? A foreign key?

A primary key is a type of attribute of an entity that uniquely identifies it on a record. While there can be multiple instances or occurrences of identities regarding entities, the job of the primary key would be to identify the uniqueness of the multiple instances since, unlike any other type of key, they must be unique, never changing, and never null. An example would be a customers, which is an entity. They have attributes, and these can be the same (such as same first and last name), and the primary key would be an attribute that uniquely identifies them by being unique, never changing and never null. Unlike primary keys, foreign keys don't have to be unique and can be repeated. However, this different does not make them different since foreign keys are primary keys in one entity, but are used in another entity to identify instances of a relationship. An example would be customer orders; the orders would would be an entity that would use the primary key of customer identification number from the customer entity. The same customer identification number may do different orders, which would repeat the identification number in the order entity but not on the order entity.

Define and describe what is a process in a process model. How should a process be named? What information about a process should be stored in a CASE repository?

A process represents actions that are performed for some specific business reason. A process should be named using a verb phrase; information regarding a process to be stored in the CASE repository includes: • Label (name) • Type (process) • Description (what it is) • Process Number • Process Description (Structured English) • Notes

How do use cases relate to the requirements stated in the requirements definition?

A use case describes in detail elements of the requirements definition. Use cases provide more detail of the processes the system is required to meet and the data the system needs to store.

What is the different between alpha testing and beta testing?

Alpha testing is in which users test the system using made-up data, and beta testing, in which users begin to use the system with real data and carefully monitor the system for errors.

In an ERD, what is an entity? An attribute? A relationship? Describe each with 2 or 3 sentences for each of the three.

An entity is a person, place, event, or thing about which data is collected. They are the most basic concept for a data model and they represent something for which there exist multiple instances or occurrences, such as customers who have the same last name. They can exist without the help of another entity (independent entity) or need attributes from its parent entity (dependent entity). An attribute, on the other hand, is some type of information that is captured about an entity. The latter can have one or more attributes and they uniquely identify them. It is important to name them as a noun with a form of the entity appended to it (sort of a prefix) to distinguish to which entity the attribute belongs to. Relationships are associations between entities and they are shown by lines that connect them together. Every relationship has a parent and child entity and, following the order, the parent is the first entity in the relationship while the second is the child entity. They are labeled with active verbs, so the connections make sense.

How do you know when an entity is in 2nd normal form? That is, what are the characteristics of an entity in 2nd normal form?

An entity is in 2nd normal form when it has two characteristics: first is that it is already in 1st normal form, and the second is that it has no partial dependency. As we know by now, a primary key is a unique attribute that distinguishes entities, and most of the values depend on that primary key. A primary key can be a composition of two different attributes and there may be attributes that are dependent on only one of those two, which causes partial dependency. The solution to remove partial dependency would be to remove the value the dependent attribute to a different entity or to an existing entity where it makes sense.

How do you know when an entity is in 3rd normal form? That is, what are the characteristics of an entity in 3rd normal form?

An entity is in 3rd normal from when it has two characteristics: it is already in its 2nd normal form, and there is no transitive dependency. Transitive dependency consists of an attribute that does not depend on the primary key but on another key that does depend on the primary key. This can be solved by making the transitive dependency in its own entity.

Define what is meant by an external entity in a process model. How should an external entity be named? What information about an external entity should be stored in the CASE repository?

An external entity is a person, organization, organization unit, or system that is external to the system but interacts with it regardless (such as customers). They provide data for the system and receive data from the system, and serve to establish the system boundaries. They are also named with nouns and, just like with data flows and stores, the information stored in the CASE repository are labels, type of entity, description, another name known as alias, an entity description, and notes.

What is the meaning of analysis? What is the purpose of the analysis phase of SDLC?

Analysis: understanding the parts' nature, function and interrelationships of the whole. The purpose of analysis in SDLC: determine step-by-step process to implement the new system. Analysis is a system proposal which includes: determining requirements, use cases, process models, and data models. Then the system proposal can be given to a committee in the form of a walk-through. A walk-through explains the system with detail to users, managers, and decision makers. If the analysis phase is accepted, then it moves onto the design phase.

What is the primary goal of integration testing?

Assess whether a set of modules or programs that must work together do so without error. To ensure that the interfaces and linkages between different parts of the system work properly.

Describe the major elements and issues with iterative development.

Breaks the overall project into a series of versions that are developed sequentially. The most important and fundamental requirements are bundled into the first version of the system. This version is developed quickly by a mini-waterfall process, once implemented, the users can provide valuable feedback to be incorporated into the next version of the system. Iterative development gets a preliminary version of the system to the users quickly so that business value is provided.

What are the key factors in selecting a methodology?

Clarity of User Requirements: How well do the users and analyst understand the functions and capabilities needed from the new system. Familiarity with Technology: How much experience does the project team have with the technology that will be used. System Complexity: How much complexity is anticipated in the new system, does the new system include a wide array of features, will the system have to integrate with many existing systems, does it span multiple organizational units or even multiple organizations. System reliability: Will this system need to be highly reliable or is some downtime tolerable. Short Time Schedule: Is the project time frame right. Schedule Visibility: Are the project sponsors, users, or organizational managers anxious to see progress?

What is meant by the characteristic of module coupling? What is its role in structure chart quality?

Coupling refers to how closely modules are interrelated. Modules should be loosely coupled so that they are independent from each other, keeping code changes in one module from affecting the rest of the program. When modules pass parameters or specific pieces of data to each other, it is known as data, which is something desirable in the chart. However, when a module refers to the inside of another, this is known as content coupling, which is not desirable.

Describe the major elements and issues with agile development.

DEFINITION: Agile development is a group of programing centric methodologies that focus on streaming the SDLC. MAJOR ELEMENTS: Communication, simplicity, feedback, and courage are core values. PROS: It emphasizes customer satisfaction and teamwork, designs are kept simple and clean, code is kept in small simple modules to be tested and meet the needs of users. CONS: It is recommended that small groups of developers (not more than 10) and is not advised for mission-critical applications. It is also difficult to perform maintenance of large systems as only code documentation is used. It also requires on-site user involvement, something that is frequently difficult to obtain.

Define and describe what is a data store in a process model. How should a data store be named? What information about a data flow should be stored in the CASE repository?

Data store is a collection of data that is stored in a way that is determined when the physical model of the process model is being created. They must have at least one input data flow and one output data flow, and these are part of the process model which are stored in the data store. The data stores are also named with nouns and the information stored in the CASE repository are the label, the type of storage, a description, another name (known as alias), description of its data elements (composition), and notes.

Compare and contrast direct conversion and parallel conversion.

Direct conversion is simple and straightforward, but also risky. Any problems with the new system that have not been detected during testing may seriously disrupt the organizations ability to function. Parallel conversion reduces risk by providing the organization with a fallback position if major problems are encountered with the new system. It adds expense, however, as users are required to do their job task twice: once with each system that performs the same function.

Compare and contrast extreme programming and throwaway prototyping.

Extreme Programming (XP): has four core values, communication, simplicity, feedback, and courage which help developers create an application. Users interact with programmers to develop a better system. Throwaway Prototype: has three core elements analyzing, designing, and building a design prototype. However, users do not interact with programmers like in XP.

Describe how project portfolio management is used by IT departments.

Historically that have tended to select projects by ad hoc methods: FIFO, pollical clout; or squeaky wheel getting the grease. Recent years IT departments have moved to :Project portfolio management- a process of selecting, prioritizing, and monitoring project results, has become a critical success factor for IT departments facing too many potential projects with too few resources.

Describe the major elements and issues with throwaway prototyping.

Includes the development of prototypes but uses the prototypes primarily to explore design alternatives rather than as the actual new system. Thorough analysis phase that is used to gather requirements and to develop ideas for the system concept. Many of the features suggested by the users may not be well understood, however, and there may be challenging technical issues to be solved. Each of these issues is examined by analyzing, designing, and building a design prototype.

A system development project may be approached in one of two ways: as a single, monolithic project in which all requirements are considered at once or as a series of smaller projects focusing on smaller sets of requirements. Which approach seems to be more successful? Why do you suppose this is true?

It is harder to determine requirements and manage a monolithic large project. Therefore, it is recommended to break the project into a set of smaller projects in order to easily make changes and manage the smaller components of the project.

Why do people resist change? Explain the basic model for understanding why people accept or resist change.

Learning to use the new system and work processes- even if the change is minor- requires more effort than continuing to use the existing, well-understood system and work processes. If the benefits of accepting the change outweigh the costs of the change, then people change. When people are presented with an opportunity for change, they perform a cost-benefit analysis and decide the extent to which they will embrace or adopt to the change. Unfortunately, most humans tend to overestimate the probability of costs and underestimate the probability of benefits.

Distinguish between logical process models and physical process models.

Logical process models describe processes without suggesting how they are constructed. Physical process models provide information that is needed to ultimately build the system.

Describe three basic principles of navigation design

Navigation design allows the use to move throughout the system, perform actions, and receive feedback messages as needed. This concept is meant to make the system as simple as possible to use. In order to manipulate the navigation controls, they should be clear and understandable and placed in an intuitive location on the screen. Its three basic principles are prevention of mistakes by labeling commands and actions appropriately and by limiting choices, not displaying commands that cannot be used, and confirmation of actions by users; making sure that mistakes can be undone; and usage of consistent grammar throughout the system.

Compare and contrast two major ways to provide system support.

Online support such as reference documentation and help screens, special websites with FAQs Help desks to provide human response

Describe the major elements and issues with system prototyping.

Performs the analysis, design, and implementation phases concurrently in order to quickly develop a simplified version of the proposed system and give it to the users for evaluation and feedback. The system prototype is quick and dirty versions of the system and provides minimal features. Following reaction and comments from the users, the developers reanalyze, redesign, and reimplement a second prototype that corrects deficiencies and adds more features.

What is a process model? What is a data flow diagram (DFD)? Are the two related? If so, how?

Process models are used to document and organize the information obtained during the analysis phase of a systems development project. Data flow diagramming is a popular technique that is used in process modeling today. Data flow diagrams document the business processes and the data that passes among them.

Discuss why testing is so essential to the development of the new system.

Recent study suggests the average cost of system downtime to be $5,600 per minute. Therefore, a form of insurance is to test the program. The attention paid to testing is justified by the high cost associated with downtime and failures caused by software bugs.

Explain what is meant by a functional requirement. What are the two types of functional requirements? Give two examples of each.

Relates to a what the system must do or what characteristics it needs to have. Process- Oriented: A process the system must perform; a process the system must do. 1) The system must allow registered customers to review their own order history for the past 3 years. 2) The system must check incoming customer orders for inventory availability Information-Oriented: Information the system must contain. 1) The system must retain customer order history for 3 years. 2) The system must include real-time inventory levels at all warehouses.

Explain what is meant by a nonfunctional requirement. What are the primary types of nonfunctional requirements? Give two examples of each. What role do nonfunctional requirements play in the project overall?

Relates to what the system behavioral properties must have. Operational: The physical and technical environments in which the system will operate. 1) The system will run on Android mobile devices. 2) The system should be compatible with Web browser. Performance: The speed, capacity, and reliability of the system. 1) Any interaction between the user and the system should not exceed 2 seconds. 2) The system downloads new status parameters within 5 minutes of a charge. Security: Who has authorized access to the system and under what circumstances. 1) Only direct managers can see staff personnel records. 2) Technicians can see only their own work assignments. Cultural and Political: Cultural and political factors and legal requirements that affect the system. 1) The system should be able to distinguish between US currency and currency from other nations. 2) Company policy is to buy computers only from Dell.

Define and describe what is a data flow in a process model. How should a data flow be named? What information about a data flows should be stored in the CASE repository?

Sometimes known as a data elements, a data flow is a single or logical collection of facts that list the flow's data elements. They show the inputs that go into processes and the outputs we get from them, and are always named with a noun. The information that should be stored in the Computer-Aided Software Engineering repository are its label, the type of flow, its description, another name (commonly known as alias), a description of its data elements (composition), and notes.

Compare and contrast structured design methodologies in general with rapid application development (RAD) methodologies in general.

Structured Design-Based Methodologies: is a chronological approach to the SDLC. For example, the waterfall development methodology is an approach that begins with Planning and follows the development of the project. Because of the development process it is difficult to go backwards which makes it time consuming. Rapid application development (RAD): is a collection of methodologies that began as a response to the waterfall development issues. It addresses the weakness of a structured design by allowing users to utilize the system so that feedback is given to the programmers, so they are able to revise the system for a better end product.

Explain the different between user documentation and system documentation.

System Documentation is intended to help programmers and systems analysts understand the application software and enable them to build it or maintain it after the system is installed. Each step and phase produces documents that are essential in understanding how the system is built or is to be built, and these documents are stored in the project binder. User Documentation is designed to help the user operate the system. Although most project teams expect users to have received training and to have read the user manuals before operating the system, unfortunately, this is not always the case. It is common for users to begin using the software without training or reading the user manual.

Compare and contrast system testing and acceptance testing.

System tests are done by system analysts to ensure that all modules and programs work together without error. Acceptance tests are done by the users with support from the project team. The goal is to confirm that the system is complete, meets the business needs that prompted the system, to be developed and is acceptable to the users.

Why is a process model typically composed of a set of DFDs? What is meant by decomposition of a business process?

The complexity of a business makes it very hard to explain their processes on one Data Flow Diagram, which is why a process model is typically composed of a set of Data Flor Diagrams. The first DFD provides a summary of the overall system, and the additional DFDs provide details about each part of the overall business process. The decomposition of a business process is an important concept for process modeling with DFDs because it decomposes it into a hierarchy, with each level down the hierarchy with less scope but more detail.

How do you determine an unnormalized (0 normal form) entity? How do you "fix it" to be in 1st normal form?

To be able to define what an unnormalized entity is, it is important to know that the purpose of normalizing an unnormalized entity is to reduce data redundancy, which is the repetition of values in attributes that increase the size of an entity. The way to determine an unnormalized entity is to see whether we have either of these three anomalies: insertion, deletion, and update. The first consists of the repetition of same values for different attributes of an entity. The second consists of deletion of these repeated values, which delete the attributes themselves until we have no single values (even those who don't repeat) for any attribute. The third talks about if a value changes for one attribute, they must be changed for every single instance of an attribute in which said value repeats, which causes a lot of trouble. The best way to fix unnormalized entities to be in 1st normal form is for every attribute in an entity to have only one value per instance, which is done by migrating repeated vales into their own entities.

What is the primary purpose of stating the primary actor for the use case?

To identify the external entity that initiates the event to which the system reacts to. It may be a user, system event, or another system.

What is the purpose of the inputs and outputs section of the use case?

To list all inputs sources, and output destinations corresponding with the proposed system.

What are the three key roles in any change management initiative?

Unfreeze - preparing people to break out of their current way of doing things Move - transition from the old to the new way of doing things Refreeze - establish the new system as the way things are done

What are the three basic steps in managing organizational change? Tell me a little about each one.

Unfreeze, move, freeze. First the project team must unfreeze the existing habits and norms so that changer is possible. Users are aware of the new system being developed, some have participated in an analysis of the current system and some help design the new system. The second is transition, from the old system to the new. The conversion strategy needs to be selected to determine the style of the switch from the old to new system, and what parts of the organization will be converted when and how much of the system is converted at a time. The this is to refreeze the new system as the habitual way of performing the work processes- ensuring that the new system successfully becomes the standard way of performing business functions it supports.

What is the purpose of developing use cases during systems analysis?

Use cases are used to explain and document the interaction that is required between user and the system to accomplish the user's task. Use cases are created to help the development team understand more fully the steps that are involved in accomplishing the user's goal.

Describe each of the problems in insertion, deletion and update anomalies that may still exist when an entity is in 1st normal form.

While normalizing unnormalized entities to the 1st normal form, there still can be problems regarding insertion, deletion, and update anomalies. If we want to insert a different value to the migrated entity, we need to insert the new value from where the migrated entity came from. If a value must be deleted in the migrated entity, then said value will stop existing where it came from. If we have to update a value in the migrated entity, then we must update it from where it came from.

What information is found on the physical DFD that is not included on the logical DFD?

While physical and logical DFDs share the same components and rules, they have a key difference: physical DFDs contain additional details that describe how the system will be built. These details that logical DFDs don't include can be seen in the following five steps: it adds references to existing logical DFDs in which data stores, data flows, and processes will be implemented; it adds a human-machine boundary that lets physical DFDs differentiate human and computer interaction; it adds additional processes, stores, or flows that are specific to the implementation of the system, having little to do with the business process itself; it updates the elements in the data flows, containing either system-related data elements, and system-generated numbers to identify each record in a data base; and it makes sure that information about DFD components in the CASE repository is updated with implementation-specific information.


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