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141.
随着3G时代的来临,在快速发展LBS业务中,一个重要功能是获得手机与手机之间或手机到地图上指定位置的最短路径.通过将路网划分成主干网与支路网,并且使用二级R*树来索引路网边,给出了一种获取手机周边道路与计算最短路径的算法.分析了该算法的复杂度,在适当划分主干网与支路网后,该算法可以缩小搜索空间,提高搜索性能.  相似文献   
142.
Prime movers of enterprise innovation are inside the organisation. The enterprise NIIT, studied in this paper, tells us how elicitation and recognition of knowledge and its contents set an enterprise on the move. Recognised knowledge is actionable. Each act of recognition is an addition to knowledge content, and such additions took place in NIIT through acts of communications and self-searching. These contents form a large collage that cannot be strewn into a single novelistic episode. Perspectives and context, motives and suggestions render to each member of the enterprise different disjoint appearances of knowledge. There are thus many knowledge systems and multiple narrations, each with small episode-like finality. Enterprise innovation is achieved not through any grand episodic integration of all knowledge contents, but by constructively eliciting further new contents of knowledge, and encouraging acts of communications and discourses on this new knowledge. Constructive management of knowledge and communication towards enterprise innovation has thus been defined. Through such constructive management, NIIT enabled itself innovationally and empowered its members in eliciting knowledge and acting communicatively. A critical feature of knowledge work is that it requires multidisciplinary expertise and mutual learning in order to achieve a complex synthesis of highly specialised state-of-the-art technologies and knowledge domains. A convivial work culture and a culture of communicative acts enable sharing of the non-informatised yet recognised contents of knowledge.  相似文献   
143.
基于图形理解的预算工程量提取算法   总被引:3,自引:0,他引:3  
分析了建筑图样(施工图)视图表达和图形理解的特点,基于工程量相关图形信息中各类图形实体的信息理解关系,提出了关联、特征实体的概念;给出施工图中工程量相关信息图形理解策略,并将图形理解的方法应用于预算工程的自动提取,为实现建筑CAD与概预算一体化提供新的途径;以土石方工程量为例,给出了工程量相关信息理解、搜索和识别算法。  相似文献   
144.
The aim of this article is to show how Human Factors and Ergonomics (HFE) methods can be used to improve urban public infrastructure systems in densely populated countries, such as India. In this case, we use Accimap analysis with crowd flow approaches to inform safety and policy. We demonstrate the need for sociotechnical systemic safety by a case study of accident analysis of the Elphinstone Road railway station stampede. On September 29, 2017, the Elphinstone Road, Mumbai, India, railway platform bridge stampede killed at least 23 and injured 39 other commuters who traveled through the Mumbai Suburban railway. In this study, we understand the accident as it is presented in newspaper articles. We analyze the accident by a sociotechnical accident analysis method called the Accimap. The Accimap method helps by identification of various stakeholders and their interactions in the different levels of hierarchy in a sociotechnical system. This ensures moving away from individualistic and blame-based accounts of media reporting to a coherent sociotechnical account based on understanding the dynamics of the situation. The findings from the Accimap analysis identify the problem areas in the commuter transit system and provide recommendations. These recommendations range from commuter flow management to enforcement of rules for supporting pedestrian flow. The article concludes with an emphasis on the development of the sociotechnical dimension of public safety and infrastructure from a human factors perspective, above and beyond what is currently practiced in India.  相似文献   
145.
This paper details a new approach for learning a discriminative model of object classes, incorporating texture, layout, and context information efficiently. The learned model is used for automatic visual understanding and semantic segmentation of photographs. Our discriminative model exploits texture-layout filters, novel features based on textons, which jointly model patterns of texture and their spatial layout. Unary classification and feature selection is achieved using shared boosting to give an efficient classifier which can be applied to a large number of classes. Accurate image segmentation is achieved by incorporating the unary classifier in a conditional random field, which (i) captures the spatial interactions between class labels of neighboring pixels, and (ii) improves the segmentation of specific object instances. Efficient training of the model on large datasets is achieved by exploiting both random feature selection and piecewise training methods. High classification and segmentation accuracy is demonstrated on four varied databases: (i) the MSRC 21-class database containing photographs of real objects viewed under general lighting conditions, poses and viewpoints, (ii) the 7-class Corel subset and (iii) the 7-class Sowerby database used in He et al. (Proceeding of IEEE Conference on Computer Vision and Pattern Recognition, vol. 2, pp. 695–702, June 2004), and (iv) a set of video sequences of television shows. The proposed algorithm gives competitive and visually pleasing results for objects that are highly textured (grass, trees, etc.), highly structured (cars, faces, bicycles, airplanes, etc.), and even articulated (body, cow, etc.). J. Shotton is now working at Toshiba Corporate Research & Development Center, Kawasaki, Japan.  相似文献   
146.
为更加精确地评价半刚性基层沥青路面的抗裂性能,系统分析了沥青路面开裂机理,依此设计抗裂测试系统的功能设计,明确其具体构造要求,并对其框架及细部进行了详细设计,基于层底应力敏感性分析确定测试的控制模式及参数范围,依据仪器的工作原理、检验指标,进行了温控系统、横向拉伸系统、竖向剪切系统设计,提出了横纵向疲劳次数作为设计参数,并开发与仪器匹配的计算机辅助分析软件并进行测试;测试系统为半刚性沥青路面的抗裂性能的评价提供了技术支撑.  相似文献   
147.
148.
This paper surveys research in developing computational models for integrating linguistic and visual information. It begins with a discussion of systems which have been actually implemented and continues with computationally motivated theories of human cognition. Since existing research spans several disciplines (e.g., natural language understanding, computer vision, knowledge representation), as well as several application areas, an important contribution of this paper is to categorize existing research based on inputs and objectives. Finally, some key issues related to integrating information from two such diverse sources are outlined and related to existing research. Throughout, the key issue addressed is the correspondence problem, namely how to associate visual events with words and vice versa.  相似文献   
149.
基于知觉加工模式的发展式分词算法   总被引:2,自引:0,他引:2  
危辉 《计算机研究与发展》2001,38(11):1281-1289
分词是自然语言理解的一个重要过程,由于语言问题又是最重要的心理学问题之一,所以从认知心理学和发展心理学的观点出发,将分词问题看成是知觉问题在语言信息处理过程中的一部分,把知觉表达和知觉的双向加工过程引入对分词问题的分析,并同时考虑言语发展的心理过程,把对言语发展规律的归纳作为构造学习算法的基础和模板,以进化的方式来逐步改进自然语言理解系统的性能,从而避免知识获取瓶颈在自然语言理解问题中的出现。  相似文献   
150.
程序理解   总被引:6,自引:0,他引:6  
程序理解是从计算机程序中获取有关信息的过程。作为程序维护中必不可少的环节,一直受到大家的关注。结合最近比较熟门的软件重建工程,分析程序理解中出现的一些问题以及解决方案。  相似文献   
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