A Triptych Software Development Paradigm - Correct System Design: Recent Insights and Advances - page 46

Fig. 2. A Hierarchical GIS+DIS Federated Information System

H = (D -> (C -> (V -> (H x Text x O x M)) x Text x O) x Text x O) x Text x O

text

h

Domain
Name
Table

text

os

Type
Designator
Table

d text

GIS data

q ts os

Version
Identifier
Table

c

q h' os

either/or

v

q

Ops

Spatially
Related
DIS data Ops

Ops

either
/ or DIS data

Ops:

Operations Table: os h' - next layer

Computational

text

Procedure

type

o

q

Operation

opn.signature

Textual

Procedure

l

n

DB
Database

Stg
Result Storage

data | here, from top left to right texts may explain domain, category and
version information). \Landscape" rectangles labelled `opn.signature' designate
descriptions of operation types. \Curtain" gures | of which there are two kinds
| designate domain/category/version sub-directories, respectively (operation,
ie. executable) code directories. The top left to right \curtain" designate sub-
-directories of domains, categories, and versions (DCV). Directories have xed
format entries (\rows"). Initial DCV sub-directory rows link to further DCV
sub-directories. Final DCV sub-directory rows link to either formatted or un-
formatted data: viz. relations, respectively images | and either directly, the
upper arrow, or indirectly, via a database reference, the lower arrow. The nal
sub-directory rows also links, in the fashion of \recursive descent", to another,
lower, layer of domain/category/version directories. The formatted or unformat-
ted data is shown as grey squares or grey \clouds". Code directories link (i) to
text briefly explaining the operation, (ii) to the type of the data needed as in-
put to the formally or informally \executed" operation and resulting from those
operations, and (iii) to either (formal, executable) code (the arrow-inxed pair
of grey \clouds"), or to text (the arrow-inxed pair of grey squares) explaining