Systems Analysis and Design Flashcards
What are the 6 phases of problem-solving procedure for examining and improving an information system?
Preliminary investigation Systems analysis System design System development Systems implementation Systems maintenance
people that study an organization’s systems to determine what actions to take and how to use computer technology to assist them
systems analysts
determines the need of an information systems
preliminary investigation (p1)
preliminary investigation is requested by ________ or ________ who wants something done that is not presently being done
an end user or a manager
what are the tasks being done on preliminary investigation?
- defining the problem
- suggesting alternative solutions
- preparing a short report
examining whatever current information system is in use and determining what information is needed, by whom, when and why is accomplished by interviewing and making observations
defining the problem
suggest some possible plans as alternatives to the present arrangement
suggesting alternative systems
the systems analyst writes a report summarizing the results of the preliminary investigation and suggest alternative systems and may also include schedules for further development of the project
preparing a short report
a short report summarizing the results of the p1 will be presented to the ___ along with a recommendation to continue or discontinue the project
higher management
management then decides whether to finance the second phase (t/f)
true
data is collected about the present system and is analyzed to determine new requirements
systems analysis
it expands the data gathered during phase 1 and adds details about how the current system works
gathering data
gathering data on systems analysis is obtained from:
observation,
interviews,
questionnaires,
studying docs that describes the formal lines of authority and standard operating procedures
learn how information currently flows and to pinpoint why it isn’t flowing appropriately
analyzing the data
apply ____ to the existing arrangement to see how workable it is
logic (analyzing the data)
tools to be used in analysis phase of system analysis
top-down analysis method grid charts system flow charts data flow diagrams automated design tools
used to identify the top-level components of a complex system
each component is then broken down into smaller and smaller components
this approach makes each component easier to analyze and deal with
top-down analysis method
shows the relationship between input and output documents
grid charts
shows the flow of input data to processing and finally to output, or distribution of information
system flowchart
shows the data or information flow within an information system
the data is traced from its origin through processing storage and input
data flow diagrams
are software packages that evaluate hardware and software alternatives according to requirements given by the systems analyst
automated design tools
automated design tools is also called as
COMPUTER-AIDED SOFTWARE ENGINEERING (CASE) tools
the systems analysts stage is typically documented in a report for higher management
describes the current information, the requirements for a new system, and a possible development schedule
management studies the report and decides whether to continue with the project (if approved, proceed to phase 3)
documenting system analysis
systems design consists of three tasks namely
designing alternative systems
selecting the best system
writing a systems design report
more than one design can be developed to meet the information needs
designing alternative systems
system designers evaluate each alternative system for feasibility namely:
economic feasibility
technical feasibility
operational feasibility
will the costs of the new system be justified by the benefits it promises?
how long will it take for the new system to pay for itself?
economic feasibility
are reliable hardware, software, and training available to make the system work?
if not, can they be obtained?
technical feasibility
can the system actually be made to operate in the organization, or will people-employees, managers, clients-resist it?
operational feasibility
(selecting the best system)
when choosing the best design, consider these four questions:
- will the system work with the organization’s overall information system?
- will the system be flexible enough so it can be modified in the future?
- can it be made secure against unauthorized use?
- are the benefits worth the costs?
it is prepared for higher management and describes the alternative designs
it presents the costs versus the benefits and outlines the effect of alternative designs on the organization
it usually concludes by recommending one of the alternatives
writing the systems design report
systems development involves three steps namely
acquiring software
acquiring hardware
testing the new system
(acquiring software) application software for the new information system can be obtained in two ways namely:
it can be purchased as off-the-shelf packaged software and possibly modified
it can be custom-designed
the equipment needed and the places where they are to be installed must be determined and is a very critical area
acquiring hardware
after the software and equipment have been installed, the system should be tested
sample data is fed into the system
the processed information is then evaluated to see whether results are correct
testing may take several months if the new system is complex
testing the new system
also called system conversion
systems implementation
it is the process of changing - converting - from the old system to the new one and training people to use the new system
systems implementation (p5)
types of conversion
direct
parallel
pilot
phased
the conversion is done simply by abandoning the old and starting up the new
this can be risky
if anything is still wrong with the new system, the old system is no longer available to fall back on
direct approach
old and new systems are operated side by side until the new one proves to be reliable
this approach is low risk
if the new sytem fails, the organization can just switch to the system to keep going
parallel approach
the new system is tried out in only one part of the organization
less expensive than the parallel approach
somewhat riskier
pilot approach
the new system is implemented gradually over a period of time
the entire implementation process is broken down into parts or phases
implementation begins with the first phase, and once it is successfully implemented, the second phase begins
this process continues until all phases are operating smoothly
expensive but least risky
phased approach
in general, these two approaches are the favored methods; namely
pilot - when there are many people in an organization performing similar operations
phased - more appropriate for organizations which people are performing different operations
training
training people is important, one of the most commonly overlooked activities
a very important, ongoing activity
systems maintenance
2 parts of systems maintenance
systems audit,
periodic evaluation
system’s performance is compared to the original design specifications
systems audit
the new information system is further modified, if necessary
all system should be evaluated from time to time to determine whether they are meeting the goals and providing the service they are supposed to
periodic evaluation
two alternative approaches that require much less time:
prototyping
rapid applications development
means to build a model or prototype that can be modified before the actual system is installed
the development time is shorter
however, it is sometimes more difficult to manage the project and to control costs
prototyping
involves the use of powerful development software, small specialized teams, and highly trained personnel
rapid applications development (RAD)
they plan and design new systems or reorganize a company’s computer resources to be utilize them
systems analysts
systems analysts can expect to earn an annual salary of:
$50k to $64k
opportunities for advancement of systems analysts include positions as
chief technology officer or other managerial opportunities
