Research On Qualitative Reasoning For Conceptual Design

In conceptual design,the details ofa structure are Insufficlentto warrantthe use ofnumeric tools traditionally used In structure analysis．MostlX In order to obtalntheresult,all kinds of prlncghes of system for analyzing and reasoning are only needed．The basic taskofqualltatlve reasoning Is to derive behavlorfrom aqualltatlvedescription ofa system structure and explain the bellavlor ofphyslcal system． Qualitative reasoning Includes two parts:qualitative model generation andqualitative reasoningaboutthe model．Based on researchingdeeply several reasoningmethods available,a qualitative model Is provided accordingic the conceptual ofconfluence Introduced by De．Kleer．Some assumptions are glvento generatethe modelforqualltatlve analysis and to carry outthe constralntpropagatlon．This paPerpresents aqualitative reasoning prototype system(QSB)and emphasizes constraint propagation．andthe causal relationship between system's parameter．Causality Is an importantaspect．Howto process the causality In system Is a sophlstlcatedproblem．plmed tthespedal problem Inthls papec we employs a causal orderingmechanlsm to create acausal dependency network．Constraint propagation Is a constraint satisfied problem(CSP)．The solution of a CSP Is generally very difficult to be got．It can be simplified toutilize the system's causal mechanism．The priority ordering developed by author IsIntroducedto avoid efficlentlyperformingwrong hypothesis and warrantthe reasoningsuccessfully．At last,an experiment system forthe qualitative analysis about the centerofgravlty Is proposedto verlfythe work In qualitative reasoning above．...