4 Communications network 
The concepts and models for communication pertain to the network area 
(local-internal, external), components (hardware, software, operators), 
capabilities (transfer rates, reliability, managment and processing, 
interactive), compatibility (hardware, software, data bases), network 
pattern (serial, central, distributed), etc. 
III DESIGN AND DEVELOPMENT 
Design and development are subject of systems engineering; the concepts 
and models are part of it. Among other things design and development ad- 
dress the following issues: 
- Evolution in the area of integrated systems, 
- Design and development itself, 
- System resources (hardware, software), 
—- Production lines, 
- Interactive operations (and human factors), 
- Automated sub-systems (vide W.g. II-2). 
] Evolution 
The evolution of integrated systems is reflected in general and specific 
trends of development. 
The general trends are from analogue to digital, from manual to 
automatic, and from small fragmented to large integrated systems. 
The specific trends are towards 
. high performing imaging systems (resolution, geometry, format), 
. powerful computer hardware (very high speed integrated circuits 
(VHSIC), super-fast microprocessor, massive parallel processor (MPP), 
and mass storage media), 
. potential interactive stations (A/N and graphic intelligent terminals, 
graph-image overlay capability), 
. versatile and intelligent software systems, 
. sophisticated data base structures, 
. increasing automation, 
. optimal integration in broader systems, 
. effective communication. 
no 
Design and development 
  
Design and development can be considered from the viewpoints of the sys- 
tem makers and the system users. A further aspect concerns the systems 
engineering stages. 
— System developers can be manufacturers of computers and computer 
graphics (or vision) facilities, of surveying and mapping instrumenta- 
tion, research institutes, software houses and mapping organisations 
(with capability for software development). 
.- System users (i.e. information producers) are various mapping organisa- 
tions and those who operate information systems, and some research and 
educational institutions. 
- Systems engineering stages can be phased in different ways, e.g., into 
study phase, problem formulation, development, evaluation, operation 
and support. 
  
  
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