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排序方式: 共有476条查询结果,搜索用时 15 毫秒
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Deuermeyer Bryan L. Foster Joseph W. Ip-Tamayo Tak Chai 《Reliability, IEEE Transactions on》1985,(4):300-302
In contract purchasing, price is often negotiated, given a reliability specification. Prior to procurement a sample is taken to determine if the product meets the reliability specification. This paper considers an alternative approach in which the contract price reflects actual field performance for an item subject to two types of failures. A consumer indifference curve that specifies the predicted break-even point between price and reliability is used to establish the initial purchase price. The actual purchase price is determined by estimating the break-even point based upon a sample of failures. Both the vendor and consumer agree upon the statistical methods for revising the price at purchase time. In this manner, more reliable products yield higher prices than less reliable products, thus resulting in a quantifiable incentive contract. 相似文献
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A pyrimidine derivative, 2-isopropyl-6-methyl-4-pyrimidinol (IMP), could be completely decomposed following pseudo-first-order kinetics by photocatalytic reaction using TiO2. The effects of pH and surface modification of TiO2 with SiOx were studied. The degradation rate of IMP was fast in mild acidic condition (pH=6.3) and slower in strong acidic (pH=2.0) or basic (pH=10.0) condition. The main reason of the slow IMP degradation was different in strong acidic and basic conditions. In strong acidic condition, the slow degradation rate was explained by electrostatic repulsion. On the other hand, a little formation of hydroxyl radicals was considered as a main reason in strong basic condition. The result was supported by the experiments using SiOx-loaded TiO2, which has a lower isoelectric point than pure TiO2. 相似文献
96.
Toward agency and ontology for web-based information retrieval 总被引:1,自引:0,他引:1
Kwang Mong Sim Pui Tak Wong 《IEEE transactions on systems, man and cybernetics. Part C, Applications and reviews》2004,34(3):257-269
This paper presents a system that selects information sources, browses websites, and monitors changes in selected websites. Its distinguishing features are 1) adopting a holistic approach for bolstering web-based information gathering using a society of agents and 2) exploiting features of ontology and lexical chain for processing user queries and filtering relevant information. By engineering web-based information gathering systems along the dimensions of agency and ontology, relations among concepts can be identified and established, and information filtering and monitoring tasks can be automated by information filtering agents (IFAs) and information monitoring agents (IMAs). IFAs and IMAs relieve users of the tasks of browsing and monitoring changes in websites and multiple web sites can be browsed and monitored in parallel by several IFAs and IMAs. By establishing ontological relations among (key)words 1) the query processing agent (QPA) selects appropriate URLs for a query and 2) IFAs search and filter information relevant to the query. Empirical results demonstrated that the QPA can find appropriate number of websites and IFAs are effective in filtering relevant information. 相似文献
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NZ Takácsi I Poller L Trón G Dabasi G Rákóczy M Füzy Z Szentirmay O Esik 《Canadian Metallurgical Quarterly》1998,139(48):2883-2888
The familial accumulation of a multiple endocrine neoplasia (MEN) type 2a medullary thyroid carcinoma, is described based on the retrospective analysis of a family history. The proband was characterized by medullary carcinoma (MC) combined with phaeochromocytoma, her child had been shown to suffer from MC. In the third generation of the family C-cell hyperplasia and bilateral adrenal hyperplasia occurred. It is shown that in order to arrive at a correct decision as regards the therapy to be used, modern laboratory tests (serum calcitonin, CEA-analysis) and diagnostic imaging methods (ultrasound, computer tomography, magnetic resonance imaging, positron emission tomography, metaiodobenzylguanidine scintigraphy) should be used. It is emphasized that the available therapeutic means (surgery, radiotherapy, nuclear medicine) have to be carefully selected and, if necessary, combined. In medullary thyroid carcinoma associated tumours in other endocrine organs should be expected to occur. Family screening using blood chemical and genetic tests are recommended in asymptomatic cases, since their surgical treatment can in this way lead to complete recovery. 相似文献
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Helida Santos Inés Couso Benjamin Bedregal Zdenko Takáč Mária Minárová Alfredo Asiaın Edurne Barrenechea Humberto Bustince 《国际智能系统杂志》2019,34(6):1281-1302
In this study, we discuss a new class of fuzzy subsethood measures between fuzzy sets. We propose a new definition of fuzzy subsethood measure as an intersection of other axiomatizations and provide two construction methods to obtain them. The advantage of this new approach is that we can construct fuzzy subsethood measures by aggregating fuzzy implication operators which may satisfy some properties widely studied in literature. We also obtain some of the classical measures such as the one defined by Goguen. The relationships with fuzzy distances, penalty functions, and similarity measures are also investigated. Finally, we provide an illustrative example which makes use of a fuzzy entropy defined by means of our fuzzy subsethood measures for choosing the best fuzzy technique for a specific problem. 相似文献