2. 4.2
A system is defined as a groups of objects that are
joined together in some regular interaction toward
the accomplishment of some purpose.
A system is often affected by changes occurring
outside the system: system environment.
• It is necessary to decide on the boundary
between the system and its environment
Definition of System
3. 4.3
Components of system
• Entity
An object of interest in the system : Machines in factory
• Attribute
The property of an entity : speed, capacity
• Activity
A time period of specified length :welding, stamping
• State
A collection of variables that describe the system in any time
status of machine (busy, idle, down,…)
• Event
A instantaneous occurrence that might change the state of
the system : breakdown
• Endogenous
Activities and events occurring with the system
• Exogenous
Activities and events occurring with the environment
4. 4.4
System can be categorized into
1. Discrete System
2. Continuous System
System
5. 4.5
A discrete system is one in which the state variables
change only at a discrete set of points in time :
(Bank example)
Discrete and Continues Systems
6. 4.6
A continues system is one in which the state
variables change continuously over time: Head of
water behind the dam
Discrete and Continues Systems
7. 4.7
Models can be classified as
mathematical, physical & Process
• A mathematical model uses symbolic notations and
mathematical equations to represent a system.
System-Model may be further classified:
• STATIC OR DYNAMIC
• DETEMINISTIC OR STOCHASTIC
• DISCRETE OR CONTINUOUS
Types of Model & System Models
8. 4.8
A STATIC SYSTEM MODEL
represents a system at a particular point in time.
DYNAMIC SYSTEM MODEL
represents a system as it change over time.
STATIC & DYNAMIC System-model
9. 4.9
System models that contain no random variables
are classified as deterministic
A stochastic system model has one or more
random variables as input.
DERERMINISTIC & STOCHASTIC System-model
10. 4.10
System models that contain no random variables
are classified as deterministic
A stochastic system model has one or more
random variables as input.
Relation among different types of system Model
