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Unit 2. General Systems Theory (GST)
41
4. The Mental Model Level
Mental models are the attitudes, beliefs, morals, expectations, and values
that allow structures to continue functioning as they are. These are the beliefs
that we often learn subconsciously from our society or family and are likely unaware of. Mental models that could be involved in us catching a cold could include: a belief that career is deeply important to our identity, that healthy food is
too expensive, or that rest is for the unmotivated.
Take a look at the diagram below to see the Iceberg Model applied to an
instance of catching a cold [4].
SPEAKING
22. Select a recent event that strikes you as urgent, important or
interesting.
Some examples include a recent hurricane, drought, or winter storm; a
controversial Supreme Court decision or a high profile court case; a local policy
change or contentious issue; recent military action between nations; or an issue
you’ve personally encountered in the last few weeks. Write the event (what is
observable about the event) at the top of the blank iceberg below and work your
way down through the patterns, underlying systems and mental models, adding
as many as you can think of. It can also be useful to move up and down between
levels as you think more about the event.
− Does the iceberg model help broaden your perspective? If so, how might
this new perspective be helpful?
− Consider the concept of entry, or “leverage” points. These are points
at which to intervene in a system that could lead to systemic transformation.
Does the exercise show you any new entry points at which you are inspired to
intervene?
− What issues that have frustrated you might be interesting to analyze with
the Iceberg Model?
Unit 2. General Systems Theory (GST)
42
UNIT 3
SYSTEM LIFE CYCLE
If your system does 25 other things,
but it doesn't do what it's supposed to, it's a failure.
LEAD IN
1. These are phases of system development life cycle. Put them in the
right order. Match these phases and the key activities.
order
phases:
key activities:
8
Production
Analisys
Implementation
Testing
Documentation
Design
Evaluation
Research
a. Collecting information about the present system
works.
b. Creating the new system from the design.
c. Coming up with a new system that will fix the pre-
sent systems problems.
d. Checking if the newly created system works as ex-
pected.
e. Replacing the present system with the new system.
f. Examining out how the present system works and
identifying problems with it.
g. Checking that the new system meets all expecta-
tions.
h. Creating documents that describe how to use the
new systems, and how it works.
PRONONCIATION
2. Make sure you pronounce the following words properly:
maintain [meɪn'teɪn]
various ['veərɪəs]
preliminary [prɪ'lɪmɪnrɪ]
feasibility [fi:zə'bɪlətɪ]
requirement [rɪ'kwaɪəmənt]
questionnaire [kwestə'neə]
ensure [ɪn'ʃuə]
scheme [ski:m]
conversion [kən'vɜ:ʃn]
emerge [ɪ'mɜ:dʒ]
3. Write the words using transcription.
_ _ _ t _ _ _
[ɪ'nɪʃl]
_ _ r _ _
['erə]
Unit 3. System Life Cycle
43
_ _ ct _ _ _
['fæktʃυǝl]
_ _ _ _ t _ _ _ s _ _ _
[rɪ'leɪʃnʃɪp]
_ _ s _ r _ _ _ _ _ _
[ɒbzə'veɪʃn]
_ _ c _ _ _ _ _ c _
[ə'kɔ:dǝns]
_ e _ _ u _ _ _ _
[rɪ'zɔ:sis]
_ _ _ _ _ _ _ g _ _ _ _ _
[ɪn vestɪ'ɡeɪʃn]
_ _ _ _ i _ _ _ _ _ _ _ _
[spesəfɪ'keɪʃn]
_ _ _ _ y _ _ _
[ə'næləsɪs]
_ _ a _ _ _ _
['ænəlɪst]
e _ _ _ r _
[ɪn'taɪə]
WORD STUDY
The following words and phrases will help you to understand the text.
4. Can you guess the meaning of each term from the context? Try to
match each term with its definition.
1. He examined the feasibility of the plan. Before we adopt a plan, let us
consider its feasibility.
2. The company is undergoing a conversion to a new computer system.
3. The initial response to the TV advertising has been very good.
4. The Systems Development Life Cycle (SDLC) is the process of creating
or altering systems, and the models and methodologies that people use to develop
these systems.
5. It is an iterative process, by which we constantly improve the program
over time.
6. Databases are structured to facilitate storage, retrieval, modification,
and deletion of data in conjunction with various data-processing operations.
7. Computer operation requires both hardware and software. Hardware
design specifies a computer's capability; software instructs the computer on what
to do.
8. The region's changeover from an agricultural economy to one based on
manufacturing.
9. I'd like to have a house built to my specifications.
10. The city council is accepting proposals for ways to use that land. The
details included in a proposal depend on the project's scope and who will read
the document.
System analyses and control
44
11. The software was full of bugs. Bugs arise from mistakes made by hu-
mans in designing programs and writing their source code.
12. The government promised to implement a new system to control loan
institutions.
13. Several mechanisms are implemented by most businesses to ensure
business continuity.
1. feasibility
2. conversion
3. initial
4. life cycle
5. iterative
6. database
7. hardware
8. software
9. changeover
10. specification
11. proposal
12. bug
13. implement
14. continuity
a. The unbroken and consistent existence or operation of
something over a period of time.
b. Of or relating to the beginning coming before all others in
time or order.
c. The physical machinery and devices that make up a com-
puter system.
d. Change in character, form, or function.
e. Situation in which a sequence of instructions can be exe-
cuted multiple times or until a specific result is achieved.
f. A progression through a series of differing stages of de-
velopment.
g. The programs and instructions used to run the system.
h. Collection of data or information organized for rapid
search and retrieval, especially by a computer.
i. The time when a new system has been tested successfully
and replaces the old system.
j. A detailed, exact statement of particulars, especially a
statement prescribing materials, dimensions, and quality of work
for something to be built, installed, or manufactured.
k. A plan that is proposed. A document that offers a solution
to a problem or a course of action in response to a need.
l. An error or flaw in a computer program that may prevent
it from working correctly or produce an incorrect or unintended
result.
m. The determination as to whether the assigned tasks could
be accomplished by using available resources.
n. To give practical effect to and ensure of actual fulfillment
by concrete measures.
5. Match the following words and word combinations with their
equivalents in Russian.
Unit 3. System Life Cycle
45
1. system life cycle
2. the feasibility study
3. on-site observation
4. preliminary system study
5. maintenance
6. system design
7. system Proposal
8. iterative process
9. computerized system
10. data dictionary
11. cost effectiveness
a. словарь данных
b. полевое наблюдение
c. проект системы
d. изучение осуществимости
e. жизненный цикл системы
f. проектирование системы
g. сопровождение
h. повторяющийся процесс
i. автоматизированная система
j. эффективность затрат
k. предварительное изучение системы
6. Match the following words with their synonyms.
1. iterative
2. initial
3. feasibility
4. investigation
5. proceed
6. conversion
7. bug
8. design
9. implement
10. correspond
11. train
12. maintain
13. review
14. evaluate
a. apply
b. possibility
c. progress
d. support
e. repetitive
f. estimate
g. changeover
h. reexamination
i. early
j. study
k. error
l. match
m. project
n. teach
7. Match the words to make word combinations.
1. user
2. on-site
3. detailed
4. programming
5. computer
6. expected
7. system
8. cost
a. effectiveness
b. functioning
c. language
d. instructions
e. requirements
f. results
g. observation
h. analysis
9. control
i. the expected results
System analyses and control
46
10. coordinate
11. remove
12. match
13. turn
14. load
15. train
16. satisfy
17. proceed
18. correct
j. through phases
k. the entire process
l. the data movements
m. the bugs
n. new user needs
o. errors
p. programs
q. users
r. theory into practice
8. Word search. Find 10 verbs to make collocations with ‘a system’.
Horizontally & Vertically only.
T E S T P X T U N E X F E T T G R D E S I G N E A X S S O C V E D D R
C
A W W G P R R U N C B
R
I M P R O V E M P U N E J E H G S H S T U D Y A Z Q O P E R A T E D L T I N V E S T I G A T E E Z M A I N T A I N E F
D
WORD BUILDING
9. Complete the chart.
Unit 3. System Life Cycle
47
verb
noun
adjective
maintenance
implement
observation
apply
iterative
requirement
expected
repetitive
GRAMMAR FOCUS
Before reading the text, revise the grammar material (§4. NON-FINITE
VERBS, GERUND, p.140) and do the exercises.
10. Identify gerunds and translate the sentences into Russian.
1. Collecting data into a form that is ready for input to a computer system
can be done in many ways.
2. Entering data into two systems, and running two systems together, takes
a lot of extra time and effort.
3. Everyday people acquire and use an array of systems, products, and ser-
vices on the pretense of improving the quality of their lives. of allowing them to
become more productive, effective, efficient, and profitable; or of depending on
them as tools for survival.
4. Finally, we conclude by presenting an analytical and graphical repre-
sentation of a system.
5. As an abstraction we symbolically represent a system as a simple entity
by using a rectangular box.
6. Engineering students often graduate without being introduced to the
root term that provides the basis for their formal education.
7. The success of man-made systems in achieving success within an or-
ganization is determined by HOW WELL the system is specified, designed, developed, integrated, verified, validated, operated, and supported.
8. A system, product, or service must be capable of supporting User mis-
sions to a level of performance that makes it operationally effective in terms of
accomplishing organizational goals and objectives, namely outcomes, cost,
schedule, and risk.
System analyses and control
48
9. System effectiveness requires understanding the contributory factors
such as reliability, maintainability, and performance.
10. If your employer is pleased with your performance on the job, he/she
will give you positive feedback by telling you that you are doing well.
11. By asking for help or by showing that you are making an honest attempt
to improve your work, you will show your employer that you want to keep your
job and that you are cooperating.
12. Choosing an appropriate life cycle methodology is not always an
easy task.
13. Understanding the software process and making tradeoffs among life
cycle components is crucially important for producing high quality software, on
time, within budget.
14. Finding the right users, ensuring their availability, and coordinating
their input is not a simple task.
15. The following factors should be considered when defining a life cycle
management method.
16. Choosing the right life cycle management methodology depends on the
nature of your program’s operational environment, stability of requirements and
technology.
17. One can think of the systems approach as an organized way of dealing
with a problem.
18. The objective of the system demands that some output is produced as a
result of processing the suitable inputs.
19. Theory is a map for observing a phenomenon.
20. System life cycle is an organizational process of developing and main-
taining systems.
21. Systems analysis is a process of collecting factual data, understand the
processes involved, identifying problems and recommending feasible suggestions for improving the system functioning.
22. The costs of implementing these features and the benefits to be derived
are estimated.
23. Before actually implementing the new system into operation, a test run
of the system is done for removing the bugs.
24. After having the user acceptance of the new system developed, the im-
plementation phase begins.
Unit 3. System Life Cycle
49
25. The hardware and the relevant software required for running the system
must be made fully operational before implementation.
26. After loading the system, training of the user starts.
SPECIALIST READING
TEXT A
SYSTEM LIFE CYCLE
System life cycle is an organizational process of developing and maintaining systems. Following are the different phases of system development life cycle:
1. Preliminary study
2. Feasibility study
3. Detailed system study
4. System analysis
5. System design
6. Coding
7. Testing
8. Implementation
9. Maintenance
Preliminary System Study
Preliminary system study is the first stage of system development life cy-
cle. The initial system study involves the preparation of a ‘System Proposal’
which lists the Problem Definition, Objectives of the Study, Terms of reference
for Study, Constraints, Expected benefits of the new system, etc. in the light of
the user requirements. The system proposal is prepared by the System Analyst.
Feasibility Study
The feasibility study is basically the test of the proposed system in the
light of its workability, meeting user’s requirements, effective use of resources
and the cost effectiveness.
Detailed System Study
The detailed investigation of the system is carried out in accordance with
the objectives of the proposed system. This involves detailed study of various
operations performed by a system and their relationships within and outside the
system. Interviews, on-site observation and questionnaire are the tools used for
detailed system study.
System analyses and control
50
System Analysis
Systems analysis is a process of collecting factual data, understand the
processes involved, identifying problems and recommending feasible suggestions for improving the system functioning. Systems analysis is an iterative process that continues until a preferred and acceptable solution emerges.
System Design
Based on the user requirements and the detailed analysis of the existing
system, the new system must be designed. Normally, the design proceeds in
two stages:
1. Preliminary or General Design: the features of the new system are spec-
ified. The costs of implementing these features and the benefits to be derived are
estimated. If the project is still considered to be feasible, we move to the detailed
design stage.
2. Structured or Detailed Design: the design of the system becomes more
structured. Input, output, databases, forms, codification schemes and processing
specifications are drawn up in detail. In the design stage, the programming language and the hardware and software platform in which the new system will run
are also decided.
Coding
The system design needs to be implemented to make it a workable system.
This demands the coding of design into computer understandable language, i.e.,
programming language. This is also called the programming phase in which the
programmer converts the program specifications into computer instructions,
which we refer to as programs. The programs coordinate the data movements and
control the entire process in a system.
Testing
Before actually implementing the new system into operation, a test run of
the system is done for removing the bugs. The output of the test run should match
the expected results.
Implementation
After having the user acceptance of the new system developed, the implementation phase begins. Implementation is the stage of a project during which
theory is turned into practice.
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