(3) A given sub-system cannot be studied in isolation as it interacts with other
sub-systems. Figure 6.1 and para. 6.2 have shown how a given sub-system
outputs may be the inputs to other sub-systems.
(4) Sometimes, systems form a hierarchy of systems, where the infrastructure
system is considered of lower rank, subject to considerable and undue influence
from those at the top and considered very important.
(5) An infrastructure system has an objective/goal, usually influenced by the
neighbouring sub-systems. Often, systems have multiple (usually conflicting)
objectives, and a compromise between these conflicting objectives has to be
determined through trade-offs, etc.
(6) For maximum efficiency operation, the infrastructure system design should try
to achieve the overall objective in the best possible way.
6.3.3 Complexity
An infrastructure system is often called complex because of the following factors:
(a) the number of interactive elements,
(b) the number of purposeful components, i.e. the number of elements that can set
their own goals and can act to satisfy these goals, irrespective of the overall goal
of the system,
(c) the number of non-linear and dynamic interactions among the components,
(d) the number of different subgoals, and
(e) the different ways in which a system interacts with its surroundings.
A system may be considered as complex because
(1) it really has an intrinsic complexity
(2) how it operates is not fully understood, or
(3) it is difficult to capture, document, and analyse the required information.
Major factors, extrinsic to a system, which make a system appear more complex
than what it actually is, are:
(a) the difficulty in measuring variable values,
(b) the difficulty in knowing the goal and sub-goal structures,
(c) the difficulty in tracking policy guidelines (the way the decisions are taken and
actions implemented),
(d) the difficulty in monitoring possible or tentative cause-effect relationships, and
(e) the difficulty in collecting data about a system and analysing it.
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sub-systems. Figure 6.1 and para. 6.2 have shown how a given sub-system
outputs may be the inputs to other sub-systems.
(4) Sometimes, systems form a hierarchy of systems, where the infrastructure
system is considered of lower rank, subject to considerable and undue influence
from those at the top and considered very important.
(5) An infrastructure system has an objective/goal, usually influenced by the
neighbouring sub-systems. Often, systems have multiple (usually conflicting)
objectives, and a compromise between these conflicting objectives has to be
determined through trade-offs, etc.
(6) For maximum efficiency operation, the infrastructure system design should try
to achieve the overall objective in the best possible way.
6.3.3 Complexity
An infrastructure system is often called complex because of the following factors:
(a) the number of interactive elements,
(b) the number of purposeful components, i.e. the number of elements that can set
their own goals and can act to satisfy these goals, irrespective of the overall goal
of the system,
(c) the number of non-linear and dynamic interactions among the components,
(d) the number of different subgoals, and
(e) the different ways in which a system interacts with its surroundings.
A system may be considered as complex because
(1) it really has an intrinsic complexity
(2) how it operates is not fully understood, or
(3) it is difficult to capture, document, and analyse the required information.
Major factors, extrinsic to a system, which make a system appear more complex
than what it actually is, are:
(a) the difficulty in measuring variable values,
(b) the difficulty in knowing the goal and sub-goal structures,
(c) the difficulty in tracking policy guidelines (the way the decisions are taken and
actions implemented),
(d) the difficulty in monitoring possible or tentative cause-effect relationships, and
(e) the difficulty in collecting data about a system and analysing it.
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