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Decision making with a fuzzy ontology 总被引:2,自引:2,他引:0
Christer Carlsson Matteo Brunelli József Mezei 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2012,16(7):1143-1152
Knowledge mobilisation is a transition from the prevailing knowledge management technology that has been widely used in industry for the last 20?years to a new methodology and some innovative methods for knowledge representation, formation and development and for knowledge retrieval and distribution. Knowledge mobilisation aims at coming to terms with some of the problems of knowledge management and at the same time to introduce new theory, new methods and new technology. More precisely, this paper presents an outline of a fuzzy ontology as an enhanced version of classical ontology and demonstrates some advantages for practical decision making. We show that a number of soft computing techniques, e.g. aggregation functions and interval valued fuzzy numbers, will support effective and practical decision making on the basis of the fuzzy ontology. We demonstrate the knowledge mobilisation methods with the construction of a support system for finding the best available wine for a number of wine drinking occasions using a fuzzy wine ontology and fuzzy reasoning methods; the support system has been implemented for a Nokia N900 smart phone. 相似文献
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Granados M. López Galisteo F. Cabello Lambrou P. S. Alifanti M. Mariscal R. Gurbani A. Sanz J. Sobrados I. Efstathiou A. M. Fierro J. L. G. 《Topics in Catalysis》2007,42(1-4):443-447
The chemical nature of P-containing species of varying concentration present in CeO2 after impregnation with (NH4)2HPO4 and calcination at 1273 K, and their effects on the oxygen storage and release (OSR) properties of ceria are reported for
the first time. The samples were characterized by different techniques and the results were compared with those recently reported
on the same samples but calcined at 873 K. When P-containing ceria solids were calcined at 1273 K, CePO4 (monazite) was the predominant P-containing species on the surface of ceria, confirming previous studies that showed that
monazite exists for those samples in which the surface P loading (P atoms per nm−2) is larger than 5.5. For lower surface P concentrations, isolated orthophosphate units are present at the surface and within
the subsurface region of the solid. Severe sintering of CeO2 after calcination at 1273 K resulted in P concentrations >5.5 P atoms·nm−2 in all samples. Isolated PO4 units that could initially be present in the samples calcined at 873 K nucleated and CePO4 was formed when samples were calcined at 1273 K. OSR properties of CeO2 deteriorated progressively when P loading increased due to the presence of larger crystals of the very stable Ce(III) phase
of CePO4 at the surface of the P-containing ceria solids. 相似文献
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Two approaches in the care of malnourished children were evaluated in order to ascertain both their medical and economical effectiveness. One was a group of 745 children under an ambulatory nutritional rehabilitation program that included health care, supplementary foods and nutrition education; a second group of 420 children attended Day Care Centers (8 hours a day and five days per week) where they received a balanced diet, psychomotor stimulation according to age, and health care. The evolution of nutritional status was followed up and plotted against the NCHS/WHO weight-for-height tables. The rate of recovery was unsatisfactory; below 50% in mild cases of malnutrition, and even less in the more severe cases. The average length of time for attaining normality was longer for moderate malnutrition and for the ambulatory program. When the calculation included a correction for the probability of recovery for each system, the advantage of the Day Care Centers became even more evident: the mean length of time for recovery was 33.2% less than the ambulatory program. The social cost per child, per day, was substantially lower in the ambulatory program. The integral calculus of social cost per child, per day, and the corrected mean time for recovery provided the social cost-effectiveness of nutritional recovery. This figure was clearly adventageous for the ambulatory program for all ages and degrees of malnutrition, exception made for moderately malnourished children below two years of age. In this case, the Day Care Centers appeared to be the most effective therapeutic alternative. This type of analysis is a contribution to the evaluation of medico-social programs for the recuperation of malnutrition. The advantage lies in the fact that it allows an optimization in the allocation of resources, when the previous step is the choice of best therapeutic alternative based upon the patient's age and nutritional status. 相似文献
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Enhancement of the basic properties of the X zeolite with FAU framework has been carried out during synthesis, without further treatment such as ion-exchange or impregnation. Control of the washing stage enables retention of the optimum amount of alkaline hydroxides, which increases the basic catalytic activity of X zeolite in the alkylation of toluene. This alkaline hydroxides neither affect the FAU framework nor the silicon/aluminium molar ratio of the X zeolite. The optimum (Na + K)/Al molar ratio of the improved catalyst was 1.06 corresponding to a washing volume of 200 mL. This X zeolite presented better catalytic activity than a cesium-zeolite prepared by ion-exchange. The presence of hydroxysodalite impurity in the X zeolite increased the amount of impregnated alkaline hydroxides but not the catalytic activity. The present study shows that it is possible to increase the basic properties of the X zeolite directly in the synthesis process. 相似文献