From: pakstas@idt.unit.no (Algirdas Pakstas)
Newsgroups: comp.groupware,comp.theory,comp.databases.theory
Subject: Proposal from S-Peterburg, Russia
Keywords: Graph-categorical concepts, object-oriented data model,
Date: 23 Jul 92 18:26:10 GMT
Reply-To: pakstas@idt.unit.no (Algirdas Pakstas)
Organization: Div. of CS & Telematics, Norwegian Institute of Technology

concurrent design, structured objects

Dear netters,

My colleague from S-Peterburg, Russia (without access to News) who
interested in cooperation with people who works in similar areas asked
me to post enclosed proposal for discussing adopted approach in
corresponding Newsgroups (Currently I send it to comp.groupware,
comp.theory, comp.databases.theory. If somebody know better place for
such subject, please, repost it).

Anyway, please, reply directly to author: Anatoly S. Kulinitch
(anat@iias.spb.su).

Thanks for your attention,

-- Algirdas Pakstas
==================================================================
Proposal:
---------
            INFORMATION SUPPORT FOR DECISION MAKING IN
              CONCURRENT DESIGN OF STRUCTURED OBJECTS

         { Graph-Categorical Concepts of  OODM  Integrity
    for concurrent engeneering of structured comples objects }

                       Anatoly Kulinitch

                   Russian Academy of Sciences
            Institute for Informatics and Automation
                     Sankt-Peterburg, Russia
                       (anat@iias.spb.su)

An approach based on  a  broadened  concept  of  integrity  of  an
object-oriented data model (OODM) concerning the development of an
information environment (IE) for concurrent design  of  structured
complex objects is suggested.

IE includes  a distributed  deductive object-oriented data
base (OODB), user's interface and OODB interface with the  applied
programs. The basic demand made  on  IE  consists  in  maintaining
integrity and consistency of  data

Hypergraph (h-graph) category  is  a  suitable  unifying  tool  to
describe varions heterogeneous  aspect  for  construction  OODM.
Formalism of h-graph context-sensitive  grammmars  is  applied  to
investigate verious aspect of modeling of logical OODB integrity.

Theory of h-graph rewritins is a base tool  for  the  solution  of
sinchronization problem in OODM updatins.  The  main  advantage  of
this approach is that there is a categorical formulation available
and  powerful   results   concerning   parallel   and   concurrent
derivations, graph production,  algebraically specified data type
Integrity and  consistency  of  data  for  concurrent  design  are
provided   by   deductive  inference  of  the  integral  integrity
restrictions (IR) for each one of its  h-graph  fragments  -  some
hyperarcs by a local closure  of  IR  of the decision to be made.

Computation of admissible OODM states is performed  through  local
constraints propagation. In this manner only  semanticaly  correct
OODB states can be generated. This approach is  used  to  generate
the process of choose rules to be applied from given finite set of
constraints rules.

The concept of OODM integrity covers such notions as integrity  of
entities and relations of Codd as well as integrity of  properties
which is introduced to enhance  semantic  capacities of the  OODM.

Amalgamation mechanism for solution  of  synchronisation  problems
within h-graph grammar  formalism - Grammar for Distributed system
(GDS)  is   applicated.   Constraction   of  locally  star  gluing
formulas is given for parallel derivation on  h-graph.  Operations
on OODM is formulated using sub h-graph  rewriting  (replacement).

Manipulation  of  OODM  is satisfied  next  mechanisms:   Local
constraint propagation; Consistency checking;  Formal  constraints
manipulation; Network consistency techniques.

IE facilities are  being  developed  with  the  use  of  C++.  The
following classes have been  created  as  base  classes:   "sorted
lists" used  to  describe  relation  schemes;  "set" (of vertices,
arcs)  for  which  theoretical-set  operations  are   implemented;
"graph" ("h-graph") for which operations are  constructed  in  the
form of virtual functions of  interfaces  of  these  classes.
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