Overview of SDSS
Expert system or ES is a computer program that reasons with
the knowledge of a specialist subject with a view to solving
problems or giving advice. Such a system may completely fulfill
a function that normally requires human expertise, or it may
play the role of an assistant to a human decision-maker. As
some functions can be performed by domain models, models are
then be used together with expert knowledge to get a more
secure result. This expert system with model component is the
preexistence of DSS, with high capability in numerical
calculation. DSS were first introduced in business management,
commercial investment and activities as strategic planning,
scheduling of business operations, and investment appraisals.
The first DSS applications began to appear in the early 1970s.
Since the early 1980s, DSS developed much under influence of
the PC revolution, the increasing performance price ratio of
hardware and software. Although there is not a generally agreed
upon definition, the term DSS commonly refers to ''computerbased
systems which help decision makers utilize data and
models to solve ill-structured problems''. In recent years, spatial
problems such as site location selection, shortest route selection,
and resource distribution plan are easy to see in our life. The
definition of SDSS can take many forms. But it is generally
agreed that SDSS is evolved from DSS and defined as a DSS
which combines geographic information with appropriate
algorithms and extend these capabilities to provide a rational
and objective approach to spatial decision analysis, a more vivid
graph expression than DSS, and thus enable the user to assess
the implications of the trade-offs between alternatives clearly.
Its primary functions are to (a) provide the mechanisms for
interactive input and manipulation of large volumes of spatial
data; (b) allow representation of the complex spatial
relationships and structures that are common in spatial data,
including analytical techniques that are unique to both spatial
analysis and modeling; (c) provide output in a variety of spatial
forms; and (d) facilitate decision-making and improve the
effectiveness of the decision made (Turban, 1988). SDSS are
explicitly designed to provide the user with an interactive
decision-making environment that enables geographic data
analysis and spatial modeling to be performed in an efficient
and flexible manner. Basic component of SDSS include control