2026-09-19T17:11:08Z https://www.ideals.illinois.edu/oai-pmh

oai:www.ideals.illinois.edu:2142/21460 2023-07-10 col_2142_5131 col_2142_10761 com_2142_5130 com_2142_10755 com_2142_234

Winslett, Marianne Collins, John William 2011-05-07T13:09:16Z 2011-05-07T13:09:16Z 10000-01-01 1994 This thesis describes a diagnostic technique for explaining unanticipated modes of failure in continuous-variable systems. Previous approaches in model-based diagnosis have traditionally suffered from either a dependence on explicit fault models or a tendency to produce unintuitive results. This research aims at achieving the explanatory power of explicit fault models, without sacrificing the robustness of consistency-based diagnosis. The unique compositional nature of the process-centered models of Qualitative Process Theory makes the application of model-based diagnostic techniques both non-trivial and rewarding. Rather than relying on explicit fault models, this approach utilizes a general domain theory to model the broken device. Given a sufficiently broad domain theory, symptoms are explained in terms of a transformed physical structure. Generative fault models replace explicit, pre-enumerated fault models, thereby increasing robustness for identifying novel faults. This approach combines the efficiency of the consistency-based approach with the explanatory power of abductive backchaining. Candidates generated using a consistency-based approach are used to focus the abductive search for a structural model of the failed system. An implementation built on a modified ATMS and an incremental qualitative envisioner is tested on a number of examples. The systems examined are taken primarily from the domain of thermodynamics, but also include some simple circuits. Made available in DSpace on 2011-05-07T13:09:16Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 9416351.pdf: 10643311 bytes, checksum: 43933ad988783c6a406edb3a010a2dcd (MD5) Previous issue date: 1994 Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T14:50:56Z Item is restricted indefinitely. Restriction data tranferred 2014-07-01T11:23:19-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: ETDs are only available to UIUC Users without author permission ETDs are only available to UIUC Users without author permission U of I Only AAI9416351 (UMI)AAI9416351 http://hdl.handle.net/2142/21460 eng Copyright 1994 Collins, John William Computer Science Process-based diagnosis: An approach to understanding novel failures text Computer Science Computer Science University of Illinois at Urbana-Champaign Dissertation Ph.D.