1l. Overall system context 
The overall context is outlined by the system objectives, which are 
users’ problem-oriented, and the description of the system area. The 
latter should include the system internal and external relationships and 
environmental factors. Examples of a system area are topographic (or 
"basic") information systems, multipurpose cadastral information systems, 
etc. The environmental factors concern such issues as volume of informa- 
tion, resources, state-of-the-art, etc. 
2. Destination, state and domain 
— Destination 
Information and data have two different destinations in a system, i.e., 
the basic and the control tasks. The basic destination refers to the 
basic information which is users’ problem— (or application) oriented. 
The control tasks concern the control data which are solution- (or in- 
formation technology) oriented. Control data provide (internal) process 
control, and include specifications for input and output. 
— States 
Associated with individual process stages are the corresponding states 
of the input and output. The process stages and thus the input-output 
states should reflect the overall system context, in particular the 
objectives. 
— Domains 
There are two distinct domains, the semantic and metric. Both are com- 
plementary and each of them can take the role of the primary or the 
secondary ingredient, and contains key-items and attributes. 
Semantic and metric domains are usually (not exclusively) involved in 
all main process stages, and refer to basic information and control 
data (table 5). 
  
FACTOR DATA BASE 
  
  
INFORMATION DATA 
Control 
(solution oriented) 
Destination Basic 
| 
(problem-oriented) | 
  
  
  
  
  
State Initial (I) Intermediate (I/O), Final (0) 
(or stage) (Collection, Processing, Presentation) 
Domain Semantic, Metric 
  
Table 5: Destination, state and domain 
Figure 9 indicates the relationships between the process stages and the 
structures of the procedures (including algorithms), of the basic infor- 
mation, and of the correspondiong spatial entities. The control data are 
implicit in these structures. The procedures and structures of the basic 
information are interrelated; hence, they should be mutually adjusted. 
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