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251.
252.
油田勘探数据中心及辅助支持系统研究 总被引:2,自引:1,他引:1
周霞 《计算机工程与应用》2003,39(24):202-204
文章简要介绍胜利油田近年来致力于勘探数据中心建设及辅助支持系统研究的背景、主要研究内容及进展情况,探讨了石油勘探行业在信息化时代利用先进的数据管理理念和技术对勘探工作提供数据支持和应用支持的尝试,对于其它油田勘探行业具有一定的借鉴意义。 相似文献
253.
Feature-based classifiers for design optimization 总被引:1,自引:0,他引:1
We present a design optimization method for systems with high-dimensional parameter spaces using inductive decision trees.
The essential idea is to map designs into a relatively low-dimensional feature space, and to derive a classifier to search
for high-performing design alternatives within this space. Unlike learning classifier systems that were pioneered by Holland
and Goldberg, classifiers defined by inductive decision trees were not originally developed for design optimization. In this
paper, we explore modifications to such classifiers to make them more effective in the optimization problem. We expand the
notions of feature space, generalize the tree construction heuristic beyond the original information-theoretic definitions,
increase the reliance on domain expertise, and facilitate the transfer of design knowledge between related systems. There
is a relatively small but rapidly growing body of work in the use of inductive trees for engineering design; the method presented
herein is complementary to this research effort. 相似文献
254.
Sebastián Bruque-Cámara Alfonso Vargas-Sánchez M. Jesús Hernández-Ortiz 《欧洲信息系统杂志》2004,13(2):133-146
The aim of this paper is to propose new organizational factors that might explain the differences in the extent and the speed of IT adoption. With this in mind, we carried out an analysis of 16 cases in the pharmaceutical distribution sector in Spain. The results indicate that there are certain intangible assets that favour the introduction and development of IT. Among these are a frank and fluid communication between departments and members of the organization, low levels of conflict, the explicit support of top management towards IT adoption and learning and creative skills of IT-staff. In addition to these factors, we found others that we propose as catalysts of IT adoption. Among these we might mention the special relationship between the member-clients and the company in the case of cooperative firms. 相似文献
255.
Weiguo Gao Yishao Zhou 《Automatic Control, IEEE Transactions on》2003,48(11):2051-2055
A computational test for scalar positive real and strictly positive real functions is proposed in this paper. The input for this algorithm is state space representation, not necessarily minimal. It is derived for the discrete time problem, based on numerical stable eigenvalue computations. The test can be used in the continuous counterpart, which is in fact an improvement of an algorithm posed by Bai and Freund. Differences between the discrete and continuous time problems are also pointed out. 相似文献
256.
Fuzzy reasoning Petri nets 总被引:2,自引:0,他引:2
Meimei Gao MengChu Zhou Xiaoguang Huang Zhiming Wu 《IEEE transactions on systems, man, and cybernetics. Part A, Systems and humans : a publication of the IEEE Systems, Man, and Cybernetics Society》2003,33(3):314-324
This paper presents a fuzzy reasoning Petri net (FRPN) model to represent a fuzzy production rule-based system. The issues of how to represent and reason about rules containing negative literals are addressed in the proposed PN model. The execution rules based on the model are defined formally using the operators in max-algebra. Then, a fuzzy reasoning algorithm is proposed to perform fuzzy reasoning automatically. The algorithm is consistent with the matrix equation expression method in the traditional PNs and allows one to exploit the maximum parallel reasoning potential embedded in the model. The legitimacy and feasibility of the proposed approach are proved and validated through a turbine fault diagnosis expert system. 相似文献
257.
258.
本文通过焊接试验对奥氏体不锈钢绕带容器环板与绕带焊接工艺进行了研究分析,并得出了合理的焊接方法和工艺参数。 相似文献
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260.