Elektronika 2009-11.pdf - Instytut Systemów Elektronicznych

useful. In work [1] is stressed, that the choice of correct strategy
- the rational decision - depends on relative importance of
the various purposes, and from a degree of confidence that
they can be achieved. The intelligent decision support systems
are used in conditions of uncertainty for a degree of confidence
increasing of the persons accepting the decisions concerning
a choice of strategy of reaction to calls of a nature.
In regional management such decisions are accepting concerning
the preventive or protective actions with the purpose of
reduction or avoidance of influence of the dangerous hydrometeorological
phenomena on economic objects, and also concerning
accommodation of economic objects at strategic
planning. Today, in conditions of climate changing and shortage
of water and power resources, such strategic decisions as accommodation
of economic objects seem to be very important [2].
In regional management and in management of economic
objects the support systems of decision’s acceptance are
used for a long time [3]. The main requirement made for intelligent
decision support systems with taking into account of
the hydrometeorological information, is presence of models
set in content of knowledge bases, including fuzzy models,
which support a strategy choice of reaction in conditions of
existing threats from the nature.
The usage of such systems is especially useful to the territories
subject influenced by the dangerous natural phenomena.
The intelligent decision support systems can be included
in structure of information systems of regional management
and cities, economic objects as local intelligent subsystems
[4]. In the case of need these subsystems, by loss of their localness,
it is possible to connect with other subsystems of information
system, or with external databases with help of
modern technologies OLAP and GIS [5].
The local intelligent systems could be used not only at
strategy choice of reaction to the warning of hydrometeorological
services on threat of the dangerous natural phenomenon,
they could be used for acceptance of decisions on
accommodation of economic objects - in strategic planning
also. Besides, the processed initial hydrometeorological information
is taking into account in designing, transport, power,
agriculture and other branches [6]. The one more purpose of
usage the local intelligent systems in conditions of threats
existence on the part of a nature is personnel training with the
purpose of formation of skills necessary in case of influence
of the dangerous hydrometeorological phenomenon. In this
case these systems act as simulators (systems of training).
Their use provides the best adaptation of management all personnel
to dangerous situations. Thus the contents of knowledge
bases of local intelligent systems - simulators should
include models, the facts and the rules used during training.
The presented work shows the representation of some fuzzy
components of the knowledge base approaches. These components
appeared during construction of infological model and
trees of decisions for the issue: “decision making on strategy
choice of reaction in view of estimations of the hydrometeorological
information”. Thus the opportunity of occurrence of hydrometeorological
situations of a different degree of the danger,
provided in the appropriate scripts is taken into account also.
Fuzzy sets and fuzzy logic
for formalization of the knowledge used
in the decision making on the base
of the hydrometeorological information
In the paper [5] the formal model of decision-making task
M DEC was submitted:
M DEC = {D J , C J n ,OJ n , AJ n , KJ n } (1)
where: D J - problem area in which the decision was made ;
C J n - the purposes of the task connected to the decision of
problem in the given area; O J n - restrictions on the task; AJ n -
set of alternative variants of the decision; K J n - set of criteria
according to which the choice of the decision was carried out.
The expression (1) presents, that the construction of infological
models of process of decision-making is directly connected
to the description of its problem area D J . Problem area
D J should be submitted by subject domain Р J and by tasks
Z J i , which are decisive in this subject domain: DJ = {Р J , Z J i }.
The results of structurization of a subject domain and construction
of trees of decisions allow to pass to definition of content’s
structure of the knowledge bases, necessary for
acceptance of decisions. However the knowledge of experts
revealed as a result of their search at structurization of a subject
domain has subjective character. It concerns areas in
which the hydrometeorological information is taken into account
in choice of strategy of reaction, too. Thus ambiguity of
the description of qualitative characteristics of objects and influence
consequences of hydrometeorological factors could
act. Besides, the hydrometeorological information too can be
also incomplete and imprecise. For this reason in creation of
knowledge bases content of local intelligent decision support
systems, accepted on the basis of the hydrometeorological
information, fuzzy sets and fuzzy logic of Lotfi Zadeh [7,8]
could be used.
Methodological bases and examples of modeling with use
of fuzzy sets and fuzzy logic are widely presented and described
in world literature, for example, by J. Kacprzyk [9,10],
A. Pegat [11], S. Russell and P. Norvig [1], A. Leonenkov [12].
It was pointed that acceptance of decisions in view of the
hydrometeorological information occurs in conditions of use of
incomplete and unreliable information. Taking into account this
fact, the block diagram of process of decision-making about
protective actions in conditions of dangerous natural phenomenon
threats it is possible to present as it shows Fig.
Figure presents, that during decision-making about strategy
of reaction to the dangerous natural phenomena fuzzy
models are used. The structure of some of them is considered
in paragraphs 2, 3.
Fuzzy modeling of the dangerous natural
phenomenon caused
by hydrometeorological factors
The dangerous natural phenomenon we shall present, as
fuzzy set:
DNP i = {p i ,µ DNPi (p i )} (2)
where: p i - the parameters of the dangerous phenomenon
submitted as linguistic variables, m DNPi - membership function
of parameter p i to an interval, which is determined by borders
of linguistic variables.
In case of usage of estimations of the indistinct hydrometeorological
information in decision-making such fuzzy linguistic
variables, as, for example, intensity of the hydrometeorological
phenomenon can be used. As an example of a linguistic
variable it should be presented it is possible to present
subjective estimation of intensity of such hydrometeorological
phenomenon, as mudflow avalanche. The intensity (volume)
of mudflow avalanche is measured in м 3 . Formalization of an
estimation of intensity of an avalanche can be executed with
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