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Unit 2. General Systems Theory (GST)
111
The components of a computer-based information system application are
summarized in Figure 1-2. We address all the dimensions of the overall system,
with particular emphasis on application software development – your primary
responsibility as a systems analyst.
Our goal is to help you understand and follow the software engineering
process that leads to the creation of information systems. As shown in Figure 3,
proven methodologies, techniques, and tools are central to software engineering
processes.
Figure 3. The software engineering process uses proven methodologies,
techniques, and tools.
Methodologies are a sequence of step-by-step approaches that help develop your final product: the information system. Most methodologies incorporate several development techniques, such as direct observations and interviews
with users of the current system.
Techniques are processes that you, as an analyst, will follow to help ensure that your work is well thought-out, complete, and comprehensible to others
on your project team. Techniques provide support for a wide range of tasks, including conducting thorough interviews with current and future users of the information system to determine what your system should do, planning and managing the activities in a systems development project, diagramming how the system will function, and designing the reports, such as invoices, your system will
generate for its users to perform their jobs.
Tools are computer programs, such as computer-aided software engineering (CASE) tools, that make it easy to use specific techniques. These three elements – methodologies, techniques, and tools – work together to form an organizational approach to systems analysis and design [17].
Unit 2. General Systems Theory (GST)
112
WORDLIST
UNIT 1
environment (n)
capability (n)
output (n)
byproduct (n)
input (n)
objective (n)
synergy (n)
interaction (n)
boundary (n)
entity (n)
accomplish (v)
constituent part (n)
confirm (v)
permit (v)
prescribed (adj)
complete (v)
require (v)
assemblage (n)
combine (v)
result (n)
bound (v)
capability (n)
validate (v)
integrate (v)
surroundings (n)
perform (v)
raw data (n)
component (n)
satisfy (v)
enable (v)
limit (v)
Wordlist
113
need (v)
potential (n)
UNIT 2
assumption (n)
cosmos (n)
approach (n)
hallmark (n)
holism (n)
equilibrium (n)
entropy (n)
chaos (n)
low (n)
order (n)
feedback (n)
teleology (n)
feature (n)
embody (v)
prove (v)
common (adj)
novel (adj)
eliminate (v)
affect (v)
attain (v)
irregularity (n)
reach (v)
exclude (v)
quality (n)
confirm (v)
influence (v)
universe (n)
incorporate (v)
general (adj)
abstract (adj)
upward (v)
include (v)
Wordlist
114
downward (n)
static (adj)
randomness (n)
concrete (adj)
UNIT 3
feasibility (n)
conversion (n)
initial (adj)
life cycle (n)
iterative (adj)
database (n)
hardware (n)
software (n)
changeover (n)
specification (n)
proposal (n)
bug (n)
implement (v)
continuity (n)
investigation (n)
proceed (v)
design (v)
implement (v)
correspond (v)
maintain (v)
review (v)
evaluate (v)
apply (v)
possibility (n)
progress (n)
support (v)
repetitive (adj)
estimate (v)
match (v)
Wordlist
115
UNIT 4
alternative (adj)
consequence (n)
certainty (n)
uncertainty (n)
probability (n)
consistent (adj)
correspondence (n)
utility (n)
criterion (plural criteria) (n)
apply (v)
attribute (n)
rank (v)
spillover (n)
be consistent (adj)
alternative (n)
select (v)
attain (v)
costs (n)
benefit (n)
choose (v)
unpredictability (adj)
likelihood (n)
usefulness (n)
profit (n)
externalities (n)
expenses (n)
accomplish (v)
option (n)
UNIT 5
constant (adj)
variable (n)
maintain (v)
measure (v)
Wordlist
116
adjust (v)
reduce (v)
intervene (v)
increase (v)
achieve (v)
actuator (n)
exhibit (v)
equation (n)
affect (v)
attempt (n)
monitor (v)
stimulus (n)
response (n)
determine (v)
measure (v)
undesirable (adj)
approximately (adj)
regulate (v)
interfere (v)
evaluate (v)
roughly (adv)
influence (v)
raise (v)
unwelcome (adj)
UNIT 6
adhere (to) (v)
ascertain (v)
cacheability (n)
compatibility (n)
comply (with) (v)
(in) conjunction (with)
constraint (n)
data breach (n)
distinguish (v)
Wordlist
117
encompass v
facet (n)
load balancing (ph)
markup language (n)
mediate (v)
query language (n)
prevalent (adj)
robust (adj)
vulnerability (n)
shared caches
unambiguously (adv)
ubiquitous (adj)
various (adj)
Unit 2. General Systems Theory (GST)
118
GRAMMAR REFERENCE
§ 1. THE PASSIVE VOICE
Normally, the performer of the action, or the agent, is the subject of the
verb and comes first in the sentence then we use the active form of the verb. The
other person or thing is made the object of the verb. For example:
The group made an important decision.
However, if you want to focus on the person or thing affected by the action, you make this person or thing the subject of the sentence and use the passive
voice:
An important decision was made by the group.
In this example the action is more important. It is the focus of the sentence.
USE
In general, the active voice emphasizes the agent of the action that is the
person, animal or object performing the action:
The director will give you instructions.
The passive voice on the other hand emphasizes the person or object receiving the action:
Instructions will be given to you by the director.
In this passive construction instructions stands out as the most important
element.
Use the passive voice:
• when the agent is unimportant, unknown, obvious, confidential, or dif-
ficult to identify.
This programming language was created in the XX century.
In the example, the focus is on the fact that this programming language
was created, but the agent is unknown. I do not know who did it.
The computer is being repaired. I don’t care about the people who are
repairing the computer. It isn’t important in my sentence.
• when the object or action itself is more important than the agent per-
forming the action:
The telephone was invented by Alexander Bell. In this sentence I want to
tell you about the telephone, not its inventor.
Grammar reference
119
• to be more polite, when you don’t want to blame anyone:
It seems that an error was made in the calculations.
In this case, the focus is on the fact that an error was made, you avoid
making accusations. Putting the emphasis on the action instead of the agent
sounds much more polite.
• to avoid responsibility for an action. For example you can say:
A mistake was made. Instead of I made a mistake.
Among other reasons, the passive is considered to be a formal reporting
structure and is commonly used in official reports, news publication and science.
FORM
The passive is a verb form that can be used in any tense in English. The
rules for tense usage are the same as in the active.
All passives are made with some form of be + a past participle verb. The
auxiliary verb 'be' changes to represent the tense.
Present simple passives are made with are/is + a past participle verb.
Past simple passives are made with was/were + a past participle verb.
Present perfect passives are made with have/has been + a past participle
verb.
Present continuous passives are made with is/are being + a past participle
verb. And so on.
It is possible to form the perfect continuous passives but it is better to
avoid these forms because of their complicated and inelegant structure.
Passive voice constructions can also be used with "modal auxiliary verbs"
(can, might, etc.) After modals we need an infinitive verb so we always use be +
past participle. Look at the examples:
Remember that only transitive verbs (it means verbs able to take an object) have both active and passive forms. Passives cannot be made in sentences
with no object. Intransitive verbs, like cry, die, arrive, disappear, wait, which
often describe physical behaviour, cannot be used in the passive voice. They have
no objects, so there is nothing to become the subject of a passive sentence.
AGENTS
The person who does the action in a passive sentence is called 'the agent'.
They may or may not be mentioned in the sentence depending on how important
they are and what the person wants to say. The agent is always introduced using
'by'. For example:
Grammar reference
120
A decision has been made by the group.
If an object was used to do the action in the passive sentence, it is called
'the instrument' and it is introduced using 'with'.
CHANGING VOICE
If you need to change voice from Active to Passive note that the object of
an active verb becomes the subject of a passive verb. The verb “to be” is used in
the same tense as the main verb of the active sentence. Then you add the past
participle of the main verb of the active sentence. Use the preposition by to introduce the agent of the action if the agent is important.
Browsers request information. – Information is requested by browsers.
5G will ensure uninterrupted connectivity. – Uninterrupted connectivity
will be ensured by 5G.
In these examples the verb has only one object.
But a verb can take two objects: a direct object and an indirect object.
Examples of such verbs are: give, send, show and lend. Normally, it is the indirect object (the object that appears first in an active sentence) which becomes the
subject of the passive sentence. Look at this example:
Reliable hardware will give you accurate data. You becomes the subject
of the passive verb. But accurate data remains the object.
You will be given accurate data.
We can also use the direct object as the subject.
Accurate data will be given to you.
So, when verbs have two objects, either object can be the subject of the
passive structure, depending on what we want to focus on. However, to use the
indirect object as the subject of a passive verb is more common.
§ 2. MODALS
There are nine modal verbs in English: must, can, could, may, might, will,
would, shall, should. Modal verbs add information to other verbs. They can add
ideas like possibility, uncertainty, or obligation to another verb. Grammatically,
modal verbs follow their own rules:
1. They have the same form for all subjects: I can, he can, we can, she
can.
2. They are followed by an infinitive without “to”, for example:
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