A Triptych Software Development Paradigm - Correct System Design: Recent Insights and Advances - page 55

, and for how we intend to combine them into (GaD) 2 I 2 S: system a Federated

GIS+DIS DSS for SD.
We have separated two concerns: the

DSS for SD from the Federated GIS+DIS .

And then we have combined them.
We usually nd the issue of \cluttered up" by the mixing of

problems of for example deciphering what spatial maps contain of information
and the \pure" issues of

DSS for SD

.
So we have separated the two issues. To then make the whole separation work
we bring the issues together.

resources , their attributes, indicators and equity functions

8.2 On Software Development

We have sketched main phase and some techniques of a new approach to software
development: One that is based on domain models on which requirements are
then based, and on requirements models on which software development is then
based.
This approach is currently under intense research, development and applica-
tion [3,4,5,6,7,8,9].
But much work needs to be done before we can fully justify our claims: we
need now carefully study relevant papers. The study will emphasize our \iso-
lation" of the etc. issues in order

to validate sections 4{5. The paper studies will then analyze the issues of geo-
graphic information system and demographic information system functionalities
in order to validate section 6.
Meanwhile we will be \building" a \prototype" (GaD) 2 I 2 S to make more
precise the

resource, attribute, indicator, equity function

items mentioned in sections 5{7, and to check
the conceptual elegance, consistency and comprehensiveness of the (GaD) 2 I 2 S
proposal.

requirements Capture

8.3 Acknowledgements

I thank (i) participants in the February 1996 UNU/IIST Workshop on Soft-
ware Technology for Agenda'21: Decision Support Systems of Sustainable De-
velopment [35,36] for instigating the modelling eort of this paper and for kind
remarks, (ii) my colleagues at UNU/IIST for enabling me to enjoy ve stimu-
lating years as rst and founding UN director of that flourishing UN University
software technology research and post-doctoral training centre in Macau, (iii)
members of the IFIP WG 2.2 and IFIP WG 2.3 Working Groups for providing
stimulating critique of my work, and (iv) Hans Langmaack for 20 years of close
friendship.

References

1. The RAISE Language Group. The RAISE Specication Language .TheBCSPrac-
titioner Series. Prentice-Hall, Hemel Hampstead, England, 1995.