In a Computer Aided Software Engineering CASE environment, the most important use of a data flow diagram is to present a graphic display of the system.. During maintenance of a system de
Trang 1Chapter 14—Construct, Deliver, and Maintain Systems Projects
TRUE/FALSE
1 The detailed design phase of the Systems Development Life Cycle is a linear process with each of five steps occurring once and in its proper sequence
ANS: F
2 In a Computer Aided Software Engineering (CASE) environment, the most important use of a data flow diagram is to present a graphic display of the system
ANS: F
3 During maintenance of a system developed using Computer Aided Software Engineering (CASE) tools, changes to the system are made directly through the data flow diagram
ANS: T
4 The Computer Aided Software Engineering (CASE) coding model transforms the structure diagram into computer code
ANS: T
5 If system development is conducted properly, most system maintenance costs can be eliminated ANS: F
6 The context level data flow diagram is a physical input to the lower CASE models that automatically produce program code
ANS: F
7 The design and programming of modern systems follows one of two basic approaches: the structured approach and the object-oriented approach
ANS: T
8 The concept of reusability is central to the structured approach to systems design
ANS: F
9 In the object-oriented approach to systems design, a vendor is an example of an attribute
ANS: F
10 In the object-oriented approach to systems design, an instance is a logical grouping of individual objects which share the same attributes and operations
ANS: F
Trang 211 In the object-oriented approach to systems design, when an operation is performed on an object, an attribute will always be changed
ANS: F
12 In the object-oriented approach to systems design, inheritance means that each object instance inherits the attributes and operations of the class to which it belongs
ANS: T
13 In the object-oriented approach to systems design, it is possible for an object class to inherit attributes and operations of another object class
ANS: T
14 The entity relationship diagram is used to represent object-oriented designs
ANS: T
15 Office automation is more complex than accounting packages
ANS: F
16 In-house developed systems are less reliable than commercial software
ANS: T
17 Output of the Management Reporting System may vary considerably among companies
ANS: T
18 Output reporting includes both paper and electronic reports
ANS: T
19 Information as to which databases are required for a new system can be obtained from the entity relationship diagram
ANS: T
20 A point-of-sale terminal is an example of electronic data input from source documents
ANS: F
21 Correctly designed, processing modules are tightly coupled and have strong cohesion
ANS: F
22 A system walkthrough occurs after the system is implemented
ANS: F
Trang 323 The detailed design report is the “blueprint” which guides programmers and database administrators in constructing the physical system
ANS: T
24 When a program module is tested, both good and bad data are included with the test transactions ANS: T
25 Instruction for the filling out of paper input forms should always be printed on a separate instruction sheet
ANS: F
26 Program modules with weak cohesion are more complex and difficult to maintain
ANS: T
27 If individual modules are thoroughly tested, it is not necessary to test the whole system
ANS: F
MULTIPLE CHOICE
1 Which statement is not true?
a prototypes do not include internal control features
b a prototype is an inexpensive, simplified model of a system
c a throwaway prototype is discarded after the requirements are established
d systems designers always discard prototypes and do not develop them into finished
systems
ANS: D
2 Which statement is not true? Computer Aided Software Engineering (CASE) technology
a is commercially available software
b reduces the productivity but increases the quality of the work of systems professionals
c expedites the System Development Life Cycle
d consists of upper and lower tools
ANS: B
3 The central repository of the Computer Aided Software Engineering (CASE) system contains
a the program code
b user prototype screens
c data flow diagrams
d all of the above
ANS: D
4 Which is not a level of a data flow diagram?
a conceptual level
b context level
c intermediate level
d elementary level
Trang 4ANS: A
5 Which level of a data flow diagram is used to produce program code and database tables?
a context level
b elementary level
c intermediate level
d prototype level
ANS: B
6 In a Computer Aided Software Engineering (CASE) environment, a structure diagram
a presents an overview model of the primary transactions processed
b graphically depicts the iceberg effect
c presents a model of the program code that constitutes the physical system
d is prepared by the systems analyst
ANS: C
7 An advantage of the Computer Aided Software Engineering (CASE) model tool, which transforms the structure diagram into machine language, is
a it facilitates the auditors review of the system
b it ensures that firm will use a specific CASE tool and vendor
c it forces all system changes to be made through the data flow diagrams
d it reduces the analysis required in designing the system
ANS: C
8 When maintaining a system that was developed using Computer Aided Software Engineering (CASE) tools,
a the programmer must thoroughly review the program code
b changes should be made directly to the structure diagram
c significantly less time is required compared to maintenance activities for a system
developed without using Computer Aided Software Engineering (CASE) tools
d the need for testing the modified application is eliminated
ANS: C
9 Which of the following is an advantage of the Computer Aided Software Engineering (CASE)
approach?
a the ability to easily revise the model during the development stage
b the requirement that all program code and documentation be regenerated for each module
c the cost of software engineering programs
d user involvement is restricted to final stages of development
ANS: A
10 Which of the following is a disadvantage of the Computer Aided Software Engineering (CASE) approach?
a source code produced by CASE tools is less efficient than code written by a skilled
programmer
b alternative designs cannot be reviewed prior to implementation
c system users are reluctant to become involved with the CASE approach
d maintenance costs are increased
ANS: A
Trang 511 Which statement is not correct? The structured design approach
a is a top-down approach
b is documented by data flow diagrams and structure diagrams
c assembles reusable modules rather than creating systems from scratch
d starts with an abstract description of the system and redefines it to produce a more detailed description of the system
ANS: C
12 The benefits of the object-oriented approach to systems design include all of the following except
a this approach does not require input from accountants and auditors
b development time is reduced
c a standard module once tested does not have to be retested until changes are made
d system maintenance activities are simplified
ANS: A
13 In the object-oriented systems design approach, the employee pay rate is an example of
a an object
b an attribute
c an operation
d a class
ANS: B
14 Ms Andrews is a customer of the Edsell Company In the object-oriented design approach
a Ms Andrews is an instance in the object class accounts receivable
b the amount Ms Andrews owes the Edsell Company is an operation
c determining the amount past due is an attribute
d the object class accounts receivable inherits all the attributes of Ms Andrews
ANS: A
15 In the object-oriented systems design approach,
a objects possess two characteristics–attributes and instances
b an instance is a logical grouping of individual objects
c inheritance means that each object instance inherits the attributes and operations of the class to which it belongs
d operations performed on objects always change attributes
ANS: C
16 Which statement is not correct? In the object-oriented design approach
a a single change to an attribute or operation in one object class is automatically changed for all the object instances and subclasses that inherit the attribute
b each module can inherit from other modules the attributes and operations it requires
c the entity relationship diagram is used to create a program which can be used in other
systems
d the control module must be recreated for each program
ANS: D
17 Evaluators of the detailed feasibility study should not include
a the internal auditor
b the project manager
Trang 6c a user representative
d the system designer
ANS: D
18 A commercial software system that is completely finished, tested, and ready for implementation is called a
a backbone system
b vendor-supported system
c benchmark system
d turnkey system
ANS: D
19 Which of the following is not an advantage of commercial software? Commercial software
a can be installed faster than a custom system
b can be easily modified to the user’s exact specifications
c is significantly less expensive than a system developed in-house
d is less likely to have errors than an equivalent system developed in-house
ANS: B
20 Which step is least likely to occur when choosing a commercial software package?
a a detailed review of the source code
b contact with user groups
c preparation of a request for proposal
d comparison of the results of a benchmark problem
ANS: A
21 The output of the detailed design phase of the Systems Development Life Cycle (SDLC) is a
a fully documented system report
b systems selection report
c detailed system design report
d systems analysis report
ANS: C
22 The detailed design report contains all of the following except
a input screen formats
b alternative conceptual designs
c report layouts
d process logic
ANS: B
23 When each element of information supports the user’s decision or task, the output is said to possess
a completeness
b summarization
c conciseness
d relevance
ANS: D
24 There is often a conflict between the attributes of
a timeliness and conciseness
Trang 7b accuracy and timeliness
c relevance and summarization
d completeness and exceptions orientation
ANS: B
25 A report of accounts that are past due has many information attributes The most important attribute is
a summarization
b timeliness
c conciseness
d exception orientation
ANS: D
26 When hardcopy forms are used as the source for electronic data input,
a a paper audit trail is maintained
b economies of scale in data collection are avoided
c input errors are reduced
d a point-of-sale terminal is required
ANS: A
27 The most important design element for a hardcopy form that is used for electronic data input is that
a the form is a standard size
b the source document and the input screen are identical
c instructions use active voice
d sufficient copies of the form are prepared
ANS: B
28 Which is not true of direct data input forms?
a errors caused by transcription are reduced
b calculations are automatically performed on intelligent forms
c many data entry errors are detected and corrected immediately
d workers who use direct data input forms must be highly trained and skilled
ANS: D
29 Which statement is not true?
a loosely coupled modules are independent of other modules
b cohesive modules perform a single, well-defined task
c maintenance of a module with weak cohesion is simple
d an error made in a tightly coupled module will affect other modules
ANS: C
30 Translating the system modules into pseudocode
a occurs in the implementation phase of the Systems Development Life Cycle
b expresses the detailed logic of the module in programming language
c discourages end users from becoming actively involved in designing the system
d permits individuals with few technical skills to understand the logic of the module
ANS: D
31 Which statement is not true? A systems design walkthrough
a is conducted by a quality assurance group
Trang 8b occurs just after system implementation
c simulates the operation of the system in order to uncover errors and omissions
d reduces costs by reducing the amount of reprogramming
ANS: B
32 System documentation is designed for all of the following groups except
a systems designers and programmers
b end users
c accountants
d all of the above require systems documentation
ANS: D
33 Which type of documentation shows the detailed relationship of input files, programs, and output files?
a structure diagrams
b overview diagram
c system flowchart
d program flowchart
ANS: C
34 Typical contents of a run manual include all of the following except
a run schedule
b logic flowchart
c file requirements
d explanation of error messages
ANS: B
35 Computer operators should have access to all of the following types of documentation except
a a list of users who receive output
b a program code listing
c a list of all master files used in the system
d a list of required hardware devices
ANS: B
36 Which task is not essential during a data conversion procedure?
a decomposing the system
b validating the database
c reconciliation of new and old databases
d backing up the original files
ANS: A
37 When converting to a new system, which cutover method is the most conservative?
a cold turkey cutover
b phased cutover
c parallel operation cutover
d data coupling cutover
ANS: C
38 What is not true about data modeling?
Trang 9a Relationships are the degree of association between two entities
b Attributes are data that describe the characteristics or properties of entities
c Entities are resources, events, or agents involved in the business
d Modeling is the task of formalizing the data requirements of the business process as a
physical model
ANS: D
SHORT ANSWER
1 Using Computer Aided Software Engineering (CASE) tools, the structure diagram can be transformed into machine code Describe a disadvantage associated with this procedure
ANS:
Auditors need to review program code, and machine code is more difficult to review than source code Also, this approach usually commits the company to a particular CASE tool and vendor while source code is accepted by most CASE tools
2 Using Computer Aided Software Engineering (CASE) tools, the structure diagram can be transformed into machine code Describe an advantage associated with this procedure
ANS:
Programmers are forced to make all changes through the data flow diagrams The CASE tool will then modify the structure diagram and rewrite the machine code automatically This ensures that the systems documentation always agrees with the computer code
3 What is prototyping? Why is it used in systems development?
ANS:
Prototyping is a technique for providing users with a preliminary working version of the new system that users can test This leads to better understanding of user needs and system requirements When used in the early stages of the SDLC, prototyping is an effective tool for establishing user
requirements
4 A bottom-up method to design a new system by assembling reusable modules is called
ANS:
object-oriented design
5 Contrast the structured and object-oriented approaches to conceptual systems design Which is more common?
ANS:
The structured approach develops each new system from scratch from the top down Object-oriented design builds systems from the bottom up through the assembly of reusable modules rather than creating each system from scratch The structured approach dominates modern system design while the object-oriented approach is still an emerging concept
6 What is meant by “object-oriented design?” What does it mean for systems design?
ANS:
Trang 10Object-oriented design refers to a “building block” approach to system design which develops systems from reusable standard components, called objects This approach avoids starting from scratch for each new system This saves time and expense for development, maintenance, and testing of systems
An example of an object is inventory Each object possesses two characteristics: attributes (part
number, description, quantity on hand, ) and operations (reorder, replace, review quantity, )
7 List three advantages and one disadvantage of commercial software
ANS:
Advantages include very quick implementation time, relatively inexpensive software, and reliable, tested software
Disadvantages include not being able to customize the system and difficulty in modifying the software
8 What is the purpose of the Request for Proposal (RFP)?
ANS:
The purpose of the RFP is to obtain proposals on supplying commercial software packages from various vendors Each prospective vendor is sent an RFP explaining the nature of the problem, the objectives of the system, and the deadline for proposal submission The RFP includes a format for responses to facilitate a comparison of the proposals from different vendors
9 Explain how a benchmark problem is used to measure the performance of two different commercial software packages
ANS:
Each prospective vendor is given the same data and task to perform (usually important transactions or tasks performed by key components of the proposed system) The results of the benchmark problem are compared for speed, accuracy, and efficiency
10 Contrast the structured and object-oriented approaches to conceptual systems design Which is more common?
ANS:
The structured approach develops each new system from scratch from the top down Object-oriented design builds systems from the bottom up through the assembly of reusable modules rather than creating each system from scratch The structured approach dominates modern system design while the object-oriented approach is still an emerging concept
11 List three characteristics that should be considered when designing a hardcopy input form
ANS:
handling, storage, number of copies, form size
12 List two techniques of forms design that encourage efficient and effective data collection
ANS:
zones and embedded instructions
13 What is the importance of the base case?
ANS: