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Two-dimensional locality preserving projections (2DLPP) was recently proposed to extract features directly from image matrices based on locality preserving criterion. A significant drawback of 2DLPP is that it only works on one direction (left or right) to reduce the dimensionality of the image matrices and thus too many coefficients are needed for image representation in low-dimensional subspace. In this paper, we propose a novel method called two-dimensional bilinear preserving projections (2DBPP) for image feature extraction. We generalized the image-based (2D-based) feature extraction techniques into bilinear cases, in which 2DLPP is a special case of our proposed method. In order to obtain the bilinear projections, we proposed an iteration method by solving the corresponding generalized eigen-equations. Moreover, analyses show that 2DBPP has stronger locality preserving abilities than 2DLPP. By using the label information and defining different local neighborhood graphs, the proposed framework is further extended to supervised case. Experiments on three databases show that 2DBPP and its supervised extension are superior to some other image-based state-of-the-art techniques. 相似文献
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This paper addresses a multi-supplier, multi-affected area, multi-relief, and multi-vehicle relief allocation problem in disaster relief logistics. A multi-objective optimisation model based on disaster scenario information updates is proposed in an attempt to coordinate efficiency and equity through timely and appropriate decisions regarding issues such as vehicle routing and relief allocation. An optimal stopping rule is also proposed to determine the optimum period of delay before responding to disaster, because decision making requires accurate disaster information. The main contribution of this paper is solving relief allocation problem in a novel way by correlating operational research with statistical decision making and Bayesian sequential analysis. Finally, a case is presented based on the post-disaster rescue in Eastern China after supertyphoon Saomai to test the applicability and show the potential advantages of the proposed model. 相似文献
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在全球经济一体化和中国已经加入WTO的大背景下,企业间的国际竞争将日趋激烈,许多国际强势陶瓷品牌将逐步登陆我国市场,也将加剧本已激烈的国内市场竞争。作为劳动密集型和资源密集型的中国陶瓷工业先必须认识到自己的差距。除了技术工艺、产品质量、品牌意识等产品意识外,还必须重视管理策略、经营方略及发展战略,陶瓷产业的信息化管理势在必行。 相似文献
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本文主要介绍了用微波等离子体化学气相沉积法(以下简称MP CVD法)以甲醇-氢气混合气和丙酮-氢气混合气为源气体,分别以单晶硅的(111)面和人造金刚石的(100)面为衬底材料,制备出了面积为20mm×20mm厚为10μm的多晶金刚石膜和面积为1.0mm×1.0mm厚为5μm的单晶金刚石膜。通过试验发现,源气体配比和衬底温度对薄膜质量起决定性作用。另外,衬底在反应腔中的位置对薄膜的生成也有很大影响。单晶金刚石膜制备过程中衬底金刚石的晶体取向与金刚石薄膜的生长及质量有密切的关系。在金刚石的(100),(110)和(111)面上分别获得了单晶金刚石膜和金刚石多晶粒子。选用扫描电镜、显微激光拉曼、反射电子衍射对多晶金刚石膜及单晶金刚石膜的性能进行了测试。 相似文献
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Automatically identifying and extracting the target information of a webpage, especially main text, is a critical task in many web content analysis applications, such as information retrieval and automated screen reading. However, compared with typical plain texts, the structures of information on the web are extremely complex and have no single fixed template or layout. On the other hand, the amount of presentation elements on web pages, such as dynamic navigational menus, flashing logos, and a multitude of ad blocks, has increased rapidly in the past decade. In this paper, we have proposed a statistics-based approach that integrates the concept of fuzzy association rules (FAR) with that of sliding window (SW) to efficiently extract the main text content from web pages. Our approach involves two separate stages. In Stage 1, the original HTML source is pre-processed and features are extracted for every line of text; then, a supervised learning is performed to detect fuzzy association rules in training web pages. In Stage 2, necessary HTML source preprocessing and text line feature extraction are conducted the same way as that of Stage 1, after which each text line is tested whether it belongs to the main text by extracted fuzzy association rules. Next, a sliding window is applied to segment the web page into several potential topical blocks. Finally, a simple selection algorithm is utilized to select those important blocks that are then united as the detected topical region (main texts). Experimental results on real world data show that the efficiency and accuracy of our approach are better than existing Document Object Model (DOM)-based and Vision-based approaches. 相似文献
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介绍冶炼烟气制本系统环保治理工程的工艺设计及生产运行情况。污水处理系统采用中和曝气加铁盐除砷工艺,引进了戈尔膜过滤器。尾气处理系统,采用石灰中和法,引进动波洗涤技术和关键设备。环保治理工程投产后,废气均达标排放。 相似文献
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新型不锈钢化学抛光剂工艺研究 总被引:1,自引:0,他引:1
叙述了一般不锈钢化学抛光溶液的基本类型和在实际应用中存在的问题。着重论述MW-6不锈钢化学抛光剂的工艺研究过程、工艺条件、质量指标及检测方法,同时介绍了它与传统不锈钢化学抛光剂的比较,经验价值,表面质量控制,应用领域及应用前景。 相似文献