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Title
The 3rd ISPRS Workshop on Dynamic and Multi-Dimensional GIS & the 10th Annual Conference of CPGIS on Geoinformatics
Author
Chen, Jun

ISPRS, Vol.34, Part 2W2, “Dynamic and Multi-Dimensional GIS", Bangkok, May 23-25, 2001
development. How to realize the GIS of the valley as soon as
possible is the problem we face.
The studies of GIS have developed by leaps and bounds
in the last 20 years. Meanwhile barriers that hindered the wider
applications of GIS were,
1), the high cost of hardware and software and the latter
would cost more than the former in the future [1];
Ml M2 M3... Mn
'1' >1 nL >1
input U(t) i
* GIS
l
In the figure is the feed time of information; T is the time of
output information; and T>t. According to the general system
theory [6], an open system has following characteristics,
1) ,Integration;
2) ,Feedback;
3) ,Equi-purpose.
Based on the theory, the design method of an information
system includes three periods as follows[7],
1) ,life period;
2) ,abstract period; and
3) ,determination period.
Here, we are going to emphasize the first period which is
relevant to the network GIS in recent years.
The first period can be divided into three phases, i.e.
(1) ,the design of information system, including the detail
explanation of the functional and technical standards of the
system;
(2) ,the realization of the system, working out programme
and commands that are concurrent with the detail standards;
(3) ,upholding the system, the purpose of which is
adapting the system to the change of the environment of the
system.
When the environment of the system takes great changes, for
example, the technology that supports the system is
out-of-date or the structure and regulations of management of
the system are revised completely, the new period of the
system begins.
With the development of GIS by leaps and bounds recent
years, the concept of Components GIS and Internet/intranet
GIS has appeared in media. This concept marked the new era
of period of GIS. And this is usually linked with computer
2) , the inefficiency of the spatial analysis system [2];
3) ,the difficulties of development of user's programme^];
4) ,the uncurrentness of data[3-5];
5) ,the gap in renewing information.
A GIS is an open dynamic system in reality. It can be
shown as following,
1 output Y(T)
>
l
networks. According to the different network structures, that is
LAN(Local Area Network),Internet(WEB),and Intranet, the
ways to construct each system are dfferent. Speciallly, three
sub-ways for Internet GIS constructing which are titled as CGI
way, Java way, and COM/DCOM way must be considered and
compared within my research work in this field
Geographically speaking, there are some important areas
and departments distributed in the valley. So the best way to
establish the GIS for the River Lanchang valley will be the
DISTRIBUTED GIS. The main problems included are three
aspects:
1, the establishment of distributed GIS in the valley of
River langchang;
2, the standards of data and the conventions for data
transmission ;
3, the data and software share in a distributed GIS with
intranet or Internet network;
4, the construction of network for the system.
3. GPS Technologies To Be used in the
LanChang Basin Area of Yunnan Province of
China
The first and important step of the project will be the
establishment of a refined control system of the
Lanchang-Mekong River valley. The project will include:
1) ,the horizontal control system; and
2) ,the vertical control system.
How to establish the control systems is the problem we face.
The establishment of horizontal control system with GPS has
been determined. The problem left is how to establish the
vertical control system in the area.