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本文系统地研究了液晶聚合物(LCP)与PVDF合金共混体系的组成及加工工艺条件对共混物制件性能的影响。并用SEM观察了合金的形态结构。结果表明:在液晶含量10%左右时,加工温度为210℃,合金的拉伸强度最高,磨耗量最低,体系分散均匀并形成了较多的微纤结构。 相似文献
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Despite the successes in the last two decades, the state-of-the-art face detectors still have problems in dealing with images in the wild due to large appearance variations. Instead of leaving appearance variations directly to statistical learning algorithms, we propose a hierarchical part based structural model to explicitly capture them. The model enables part subtype option to handle local appearance variations such as closed and open month, and part deformation to capture the global appearance variations such as pose and expression. In detection, candidate window is fitted to the structural model to infer the part location and part subtype, and detection score is then computed based on the fitted configuration. In this way, the influence of appearance variation is reduced. Besides the face model, we exploit the co-occurrence between face and body, which helps to handle large variations, such as heavy occlusions, to further boost the face detection performance. We present a phrase based representation for body detection, and propose a structural context model to jointly encode the outputs of face detector and body detector. Benefit from the rich structural face and body information, as well as the discriminative structural learning algorithm, our method achieves state-of-the-art performance on FDDB, AFW and a self-annotated dataset, under wide comparisons with commercial and academic methods. 相似文献
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In order to solve the transformation problem of Bill of Materials (BOM) from engineering BOM to maintenance BOM for Maintenance, Repair and Overhaul (MRO) systems, a formal transformation model of BOM view is proposed. In this model, the intermediate component, inherited component, virtual component are defined in the specific maintenance management domain, and the transformation process from engineering BOM to maintenance BOM is discussed through feature recognition methods and rules. The proposed transformation model has been developed and deployed in an MRO system for a steel manufacturing enterprise. 相似文献
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We propose a parametric weighting function for weighted ordered weighted averaging (WOWA) operator in decision making under uncertainty and risk environment. The weighting function is not only related to the attitude of the decision makers, but also to the event probability. Under the proposed method, the decision makers underweight small probability gains and overweight large probability gains, which is right in consistence with the psychology of the decision makers in the prospect theory. Meanwhile, it generalizes two specific weighting functions and proposed by Torra (International Journal of Intelligent Systems 12 (1997) 153–166). Moreover, the expected utility becomes a special case of the parametric weighting function for WOWA operator. To illustrate its application, an example of introducing and pricing new product is given, which shows the optimal strategies corresponding to different parameter values r. 相似文献