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Imperfection in information can be considered a crosscutting concern that manifests itself in diverse kinds of imprecision, uncertainty, or inconsistency in the data models of a software system. The extension of existing programming and querying interfaces for the different aspects of information imperfection requires a proper modularization of the different concerns of numerical imprecision handling, so that the extensions do not interfere with existing programming practices and do not obscure the original design. Aspect‐oriented design (AOD) enables such a form of nonintrusive extensions to be added to existing software libraries, clearly separating fuzziness or other imperfections in data as a differentiated concern that can be considered from the early phases of development. In this article, a general framework for aspect‐based extension of data models and fuzzy databases is described, and some design and implementation issues of such AOD‐based extensions on OJB database libraries are described as a case study. © 2006 Wiley Periodicals, Inc. Int J Int Syst 21: 1199–1216, 2006. 相似文献
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The objective of this study is to determine the chemical kinetics of desulphurization of Thai limestone in an atmospheric fluidized bed combustor (AFBC). The experiments, which employed the batch technique using the limestone samples from six major sources in Thailand, were performed in a laboratory‐scale AFBC. The results obtained were analysed and correlated in the form of apparent reaction rate and deactivation rate constants as a function of operating conditions of the furnace and their properties, respectively. The formulae derived from these correlations were kept as general as possible in order that they could be used as input parameters for the selected mathematical model of desulphurization in an AFBC that is suitable for practical use. The predicted results were in good agreement with the experimental data reported in the literature. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
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Failure analysis of hollow glasses The failure analysis is very important to clarify damages of hollow glasses. Damages of glass bottle through over pressure are very often linked with damages to persons. This is the reason why the causal research is from particular importance. Different surface characteristics of glass fragments as well as the fracture pattern give hints to the direction of the crack, the stress just before breakage and the reason of stress. A reconstruction of the bottle is a further helpful instrument for cause studies. The difference of the various characteristics of the surface will be explained. Further on there will be discussed different reasons and mechanism of fracture. 相似文献
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化学镀Ni—P镀层的X射线衍射研究 总被引:2,自引:0,他引:2
根据X射线衍射分析结果,对化学镀高P(含P>11wt%或19at%)Ni-P镀层加热时效时,镀层成分和加热温度对结构转变的影响作了研究,结果表明,高P共晶、过共晶(含P>11wt%或19at%)合金的结构转变有如下特征:(1)相同加热时效条件下,Ni-P合金的结构转变与成分有密切关系:(2)对同一成分的过共晶合金,Ni-P合金的结构转变与时效温度密切相关;(3)过共晶合金在290~360℃温度范围内时效处理,出现Ni_xP_y介稳相,X射线衍射分析认为Ni_xP_y为Ni_(12)P_5。 相似文献
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Hanna Pietil inen Tarja Saesmaa Veli-Pekka Tanninen 《Drug development and industrial pharmacy》1996,22(11):1063-1073
In order to investigate the formation of organic salts of drugs, two salts of pindolol were prepared using salt-forming agents which were crystalline and suitable for physical studies in the solid state. The stoichiometry of the products, pindolol benzoate and pindolol 2-methoxyphenylacetate, was established by elemental analysis. The precipitates formed were assessed by differential scanning calorimetry (DSC), thermogravimetry (TG), x-ray powder diffractometry (XRPD) and Fourier transform-infrared spectrometry (FT-IR). According to the TG and DSC curves, there was no water of crystallization in the precipitates, and the products were thermally stable. Both precipitates gave one sharp melting endotherm which differed from the endotherms of the starting compounds. The x-ray dipaction pattern of the precipitates direred clearly from those of the starting materials, acid and base. The products showed absorption by FT-IR typical of carboxylic acid salts at about 1640-1540 cm-1. The carbonyl absorption indicative of the carboxylic acid group of benzoic acid or 2-methonyphenylacetic acid was not detectable in the spectra of the precipitates. All this indicates that two new crystalline organic salts (1:1) were formed during the syntheses. 相似文献