44221: Information Systems Lecture 3 (Week 4) Systems Concepts 2 By Ian Perry

44221: Information Systems

Lecture 3 (Week 4)

Systems Concepts 2

By Ian Perry

http://itsy.co.uk/ac/0607/Sem1/44221_IS/

Ian Perry Slide 244221: Information Systems: Systems Concepts 2

Our Systems ‘view’ so far …

System

Sub-system

Element

Element Sub-system

Element

Element

Element

Sub-system

Element

Element

CustomersSuppliersCompetitors

The Government

A System is composed of Elements grouped into Sub-systems.

A System has a Boundary (which separates it from other Systems) and a ‘unique’ Identity (which distinguishes it from similar Systems).

A System ‘exists’ within other Systems; which are referred to as the Environment of that System.


Components Systems are an organised whole,

consisting of a number of component parts, i.e.; the Elements & Sub-systems.

Components: Have a Form, which might be:

Concrete Abstract

Have Attributes, which might be: Hard Soft


Concrete v Abstract Form Concrete components; have a physical

existence, and can be detected by at least one of our senses. Concrete components tend to ‘appear’ the same to

different individuals. E.g. a Human Being.

Concrete Money = the Coins & Notes in my Pocket. Abstract components; have no physical

existence, so you can’t see, touch, hear, or smell them. Abstract components may ‘appear’ differently to

different individuals. E.g. a Pretty/Ugly Person.

Abstract Money = my Total Worth.


Hard v Soft Attributes Hard components; do not depend upon

someone’s personal sense of value. Easy to define/quantify/measure.

E.g. The dimensions of a Room. Hard Money = number of £1 Coins in my pocket.

Soft components; have no agreed objective test to prove one person right or wrong. Hard (impossible?) to define/quantify/measure.

E.g.: A nice Room. Soft Money = Value for money.


So What? Beware the Abstract/Soft.

Concrete/Hard Components, are quite easy to identify, as they:

tend to ‘appear’ the same to different individuals. and are easy to define/quantify/measure.

Abstract/Soft Components, are often difficult to identify, as they:

may ‘appear’ differently to different individuals. and are, therefore, difficult to

define/quantify/measure.

Do NOT, however, ignore the Abstract/Soft; as all Systems contain Abstract/Soft

Components.


Holism Systems thinking is all about considering

the whole System; and its relationship with other whole Systems.

The general principle of holism, as concisely stated by Aristotle, is that; “The whole is more than the sum of its parts”.

A more modern definition is that; the properties of a given system cannot be

determined or explained by the sum of its component parts alone.

(http://en.wikipedia.org/wiki/Holism)


Emergent Property Emergent Properties;

occur/arise; because of the interaction between the

components of a System and its environment. result in;

what the System as a whole, or a component of the System (i.e. Sub-system and/or Element), is supposed to (i.e. has been designed to) achieve.

may not always be as intended; e.g. users may adapt products to support tasks

that designers never intended.


Components, Holism, Emergent Property

AeroplaneFuselageTail

WingEngine

Flight

a Hard/Concrete Example


Components, Holism, Emergent Property

OrderProcessing

CustomerRequirements

ProductKnowledge

CustomerSatisfaction

a Soft/Abstract Example


Connection & Interaction Systems do NOT ‘exist’ in isolation:

they are both ‘connected to’ and ‘interact with’ other Systems.

Connection between Systems may be: Permanent or Ad-hoc.

Interaction between Systems is, in most cases, considered to be: A two-way process.


Connection & Interaction (continued)

System ASub-system

Element

Element

Element

Sub-system

Element

Element

Element

System CSub-system

Element

Element

Element

Sub-system

Element

Element

Element

System B

Sub-system

Element

Element Sub-system

Element

Element

Element

Sub-system

Element

Element

System A is ‘usually’ supplied with raw materials by System B.

However, if System B is unable to supply ‘enough’ raw materials, they can be sourced from System C.



Naming the Sub-systems can make the Connections & Interactions easier to understand.

CompetitorsGovernment

System

Customer Services

Warehousing

Manufacturing

Element

Customers

Suppliers

Element Element

ElementElement

Element

Element



Customer ServicesCustomers

Sub-System

Warehousing

Manufacturing

Sub-System

Sub-System

Element Element

ElementElement

ElementElement

Element

Concentrate on ONE of the original Sub-systems at a time; and ‘view’ it as a System, in order to explore the Connections & Interactions in more detail.

NB. The Sub-systems of this ‘view’ were the Elements of the previous ‘view’ of the whole System.


Systems Concepts from this Lecture Components

Concrete/Abstract Form Hard/Soft Attributes

Holism & Emergent Property Connection & Interaction


This Week’s Workshop Apply the information systems concepts

from this week’s Lecture, in order to; analyse, in greater detail, the business as

described by the ‘Local Parts’ Case Study. In advance of the Workshop session:

Read the updated Case Study; attempt to answer the questions; and be prepared to contribute.

Assignment 1? I hope you have all had a go at Assignment

1 by now. If not, then don’t leave it too late to begin; IS Analysis is NOT a trivial task.

44221: Information Systems Lecture 3 (Week 4) Systems Concepts 2 By Ian Perry

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