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991.
High dimensional data contain many redundant or irrelevant attributes, which will be difficult for data mining and a variety of pattern recognition. When implementing data mining or a variety of pattern recognition on high dimensional space, it is necessary to reduce the dimension of high dimensional space. In this paper, a new attribute importance measure and selection methods based on attribute ranking was proposed. In proposed attribute selection method, input output correlation (IOC) is applied for calculating attribute’ importance, and then sorts them according to descending order. The hybrid of Back Propagation Neural Network (BPNN) and Particle Swarm Optimization (PSO) algorithms is also proposed. PSO is used to optimize weights and thresholds of BPNN for overcoming the inherent shortcoming of BPNN. The experiment results show the proposed attribute selection method is an effective preproceesing technology. 相似文献
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我国风电行业面临着诸多待解的难题,其中弃风限电是制约我国风电发展的最大障碍。由此所导致的企业资金紧张和项目开工不足等问题,已经影响到我国风电规划目标的实现和发电产业的长远发展。同时,企业金融处境、市场竞争环境、国际竞争压力以及管理水平等方面,也不同程度地存在亟待解决的问题和需要克服的障碍。 相似文献
995.
Jianjun Qin Michael Havbro Faber 《Computer-Aided Civil and Infrastructure Engineering》2012,27(6):385-405
Abstract: The present article addresses the development of a spatial information system (SIS), which aims to facilitate risk management of large‐scale concrete structures. The formulation of the SIS is based on ideas developed in the context of indicator‐based risk modeling for concrete structures subject to corrosion and geographical information system based risk modeling concerning large‐scale risk management. The term “risk management” here refers in particular to the process of condition assessment and optimization of the inspection and repair activities. The SIS facilitates the storage and handling of all relevant information to the risk management. The probabilistic modeling utilized in the condition assessment takes basis in a Bayesian hierarchical modeling philosophy. It facilitates the updating of risks as well as optimizing inspection plans whenever new information about the condition of the structure becomes available. In the SIS, the various data of relevance for the risk management can be visualized in three dimensions. This feature and the other functionalities of the SIS are illustrated in an example considering the Danish Farø bridges. 相似文献
996.
互联网上的虚假事实陈述严重影响人们有效地获取信息,如何判定事实陈述是否可信成为一个亟待解决的问题.文中提出了一种针对事实陈述的可信判定模型MFSV.该模型针对事实陈述的特点,从互联网上搜集与待判定事实陈述相关的文本信息,度量其与对应事实陈述的语义相似度;同时,该模型考虑了相关文本信息在可信度上的差别,从受欢迎程度和重要程度两个方面度量了相关文本信息来源的可信度,并获取了相关文本信息的可信度排序;根据语义相似度以及可信度排序,衡量了相关文本信息对对应事实陈述可信判定所做出的贡献,并以此为基础实现了待判定事实陈述的可信判定.一系列的实验验证了该模型的合理性及可信判定的准确性. 相似文献
997.
Jianglei Qin Hongzhi Liu Pei Zhang Michael Wolcott Jinwen Zhang 《Polymer International》2014,63(4):760-765
In this study, an epoxy based on eugenol and an anhydride curing agent based on rosin were prepared. Curing of the eugenol epoxy with a commercial anhydride curing agent and with the rosin‐derived anhydride curing agent was studied. For comparison, a commercial bisphenol A type epoxy, DER353, was also selected in the curing study. The syntheses of the eugenol epoxy and rosin anhydride were investigated and the chemical structures of the products and intermediates were characterized using 1H NMR and Fourier transform infrared spectroscopies. Non‐isothermal curing of the eugenol epoxy with hexahydrophthalic anhydride and the rosin‐derived maleopimaric acid was studied using differential scanning calorimetry. Thermomechanical properties and thermal stability of the cured epoxy resins were evaluated using dynamic mechanical analysis and thermogravimetric analysis, respectively. Addition of 2‐ethyl‐4‐methylimidazole as catalyst greatly decreased the curing temperature and promoted the completion of cure reactions. The results suggest that the eugenol epoxy and the bisphenol A type epoxy have similar reactivity, dynamic mechanical properties and thermal stability. © 2013 Society of Chemical Industry 相似文献
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Wang Hui Qin Qing-Hua Lei Yong-Peng 《Journal of Mechanical Science and Technology》2017,31(3):1305-1313
Journal of Mechanical Science and Technology - In the paper, an anisotropic Green’s function based hybrid finite element was developed for solving fully plane anisotropic elastic materials.... 相似文献
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