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Categorization Scheme (categorization + scheme)
Selected AbstractsCategorizing approaches combining rule-based and case-based reasoningEXPERT SYSTEMS, Issue 2 2007Jim Prentzas Abstract: Rule-based and case-based reasoning are two popular approaches used in intelligent systems. Rules usually represent general knowledge, whereas cases encompass knowledge accumulated from specific (specialized) situations. Each approach has advantages and disadvantages, which are proved to be complementary to a large degree. So, it is well justified to combine rules and cases to produce effective hybrid approaches, surpassing the disadvantages of each component method. In this paper, we first present advantages and disadvantages of rule-based and case-based reasoning and show that they are complementary. We then discuss the deficiencies of existing categorization schemes for integrations of rule-based and case-based representations. To deal with these deficiencies, we introduce a new categorization scheme. Finally, we briefly present representative approaches for the final categories of our scheme. [source] Quasilocal defects in regular planar networks: Categorization for molecular conesINTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, Issue 4-5 2003D. J. Klein Abstract Graphical networks are cast into structural equivalence classes, with special focus on ones related to two-dimensional regular translationally symmetric nets (or lattices). A quasilocal defect in a regular net is defined as consisting of a finite subnet surrounded outside this region by an infinitely extended network of which arbitrary, simply connected regions are isomorphic to those of the regular undefected net. The global equivalence classes for such quasilocal defects are identified by a "circum-matching" characteristic. One or more such classes are identified as a "turn" number, or equivalently as a discrete "combinatorial curvature" ,, which associates closely to the geometric Gaussian curvature of "physically reasonable" embeddings of the net in Euclidean space. Then for positive ,, geometric cones result; for , = 0, the network is flat overall; and for negative ,, fluted or crenalated cones result. As , or q varies through its discrete range, the number of defect classes varies between 1 and , and repeats with a period depending on the parent regular net. For the square-planar net, the numbers of defect classes at succeeding turn numbers (q) starting at q = 0 are ,, 2, 3, 2, repeating with a period of 4. For the hexagonal and triangular nets, the numbers of classes at suceeding q starting at q = 0 are ,, 1, 2, 2, 2, 1, repeating with a period of 6. A further refinement of the classes of quasilocal defects breaks these classes up into "irrotational" subclasses, as are relevant for multiwall cones. The subclasses are identified via a "quasispin" characteristic, which is conveniently manipulatable for the categorization of multiwall cones. Besides the development of the overall comprehensive topo-combinatoric categorization scheme for quasilocal defects, some consequences are briefly indicated, and combining rules for the characteristics of pairs of such defects are briefly considered. © 2003 Wiley Periodicals, Inc. Int J Quantum Chem, 2003 [source] Major hazards analysis: An improved method for process hazard analysisPROCESS SAFETY PROGRESS, Issue 1 2003Paul Baybutt Process hazard analyses (PHAs) usually focus on major hazards,fires, explosions, and toxic releases. Traditional PHA methods, such as the Hazard and Operability (HAZOP) study and What-If analysis, often include scenarios for other hazard types, such as operability problems. Sometimes, this may be desired, but not always. There is a need for a PHA technique that directly and exclusively addresses major process hazards. Such hazards are realized when process containment is lost. Therefore, the method proposed here uses a categorization scheme to guide brainstorming of initiating events that can result in fires, explosions, or toxic releases. It provides a more efficient and, likely, more complete, identification of major hazard scenarios than current PHA methods. [source] Categorizing approaches combining rule-based and case-based reasoningEXPERT SYSTEMS, Issue 2 2007Jim Prentzas Abstract: Rule-based and case-based reasoning are two popular approaches used in intelligent systems. Rules usually represent general knowledge, whereas cases encompass knowledge accumulated from specific (specialized) situations. Each approach has advantages and disadvantages, which are proved to be complementary to a large degree. So, it is well justified to combine rules and cases to produce effective hybrid approaches, surpassing the disadvantages of each component method. In this paper, we first present advantages and disadvantages of rule-based and case-based reasoning and show that they are complementary. We then discuss the deficiencies of existing categorization schemes for integrations of rule-based and case-based representations. To deal with these deficiencies, we introduce a new categorization scheme. Finally, we briefly present representative approaches for the final categories of our scheme. [source] Animal use replacement, reduction, and refinement: Development of an integrated testing strategy for bioconcentration of chemicals in fish,INTEGRATED ENVIRONMENTAL ASSESSMENT AND MANAGEMENT, Issue 1 2007Watze de Wolf Abstract When addressing the use of fish for the environmental safety of chemicals and effluents, there are many opportunities for applying the principles of the 3Rs: Reduce, Refine, and Replace. The current environmental regulatory testing strategy for bioconcentration and secondary poisoning has been reviewed, and alternative approaches that provide useful information are described. Several approaches can be used to reduce the number of fish used in the Organization for Economic Cooperation and Development (OECD) Test Guideline 305, including alternative in vivo test methods such as the dietary accumulation test and the static exposure approach. The best replacement approach would seem to use read-across, chemical grouping, and quantitative structure-activity relationships with an assessment of the key processes in bioconcentration: Adsorption, distribution, metabolism, and excretion. Biomimetic extraction has particular usefulness in addressing bioavailable chemicals and is in some circumstances capable of predicting uptake. Use of alternative organisms such as invertebrates should also be considered. A single cut-off value for molecular weight and size beyond which no absorption will take place cannot be identified. Recommendations for their use in bioaccumulative (B) categorization schemes are provided. Assessment of biotransformation with in vitro assays and in silico approaches holds significant promise. Further research is needed to identify their variability and confidence limits and the ways to use this as a basis to estimate bioconcentration factors. A tiered bioconcentration testing strategy has been developed taking account of the alternatives discussed. [source] The new ATS/ERS guidelines for assessing the spirometric severity of restrictive lung disease differ from previous standardsRESPIROLOGY, Issue 5 2007Ashutosh N. AGGARWAL Background and objectives: The ATS/ERS Task Force on Lung Function Testing recently proposed guidelines for the interpretation of pulmonary function tests and suggested that a reduction in FEV1 be used for categorizing both obstructive and restrictive abnormalities. This changes the severity stratification algorithm of restrictive patterns diagnosed by spirometry, that are currently categorized based on reduction in VC. This study examined the level of agreement between these two categorization schemes. Methods: Spirometry records of 2527 adult patients evaluated over 1 year were retrieved; 361 of these patients showed a restrictive pattern. Severity of airway restriction was separately assessed in these patients using the indicative schemes provided in the new ATS/ERS and the earlier ATS guidelines. Results: There were 212 (58.7%) patients with a restrictive pattern who had identical severity categorization using both guidelines. In most instances of discordance, the severity categorization differed only by a single stratum. Of 149 discordant results, 91 (60.1%) were placed in a better category, and 58 (39.9%) in a worse category, when using the new ATS/ERS recommendations. Overall weighted kappa estimate for agreement between the two schemes of categorization was 0.649. Conclusion: Based on spirometry results, the level of severity of restriction cannot be described interchangeably between the old and new guidelines for all patients. The new guidelines tend to give lower severity scores for restrictive lung diseases in up to 25% of patients. [source] | |||||||||||||