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161.
用双层减样法优化大规模SVM垃圾标签检测模型*   总被引:1,自引:1,他引:0  
针对支持向量机在训练大规模数据集时出现的速度瓶颈问题,提出一种新的减样方法,称双层减样法。数据减样时,双层减样法从粗、细粒度两个层次削减样本。粗粒度约减时,利用核空间距离聚类法,以簇为单位削减冗余子集。细粒度约减时,以点为单位挑选剩余点集中的支持向量。实验表明,双层减样法能有效的压缩样本数据,同时还能放大数据集的分类特征,提高分类器的分类精度。将此法应用于大规模SVM垃圾标签检测模型的训练集优化上,能明显提高检测模型的训练速度。双层减样法是将“粒度”和“层次”的概念引入减样法中,在约减时适时改变约减幅度。这比传统减样法更具有优势。  相似文献   
162.
在线社会网络已得到广泛应用,综合利用在线社会网络的社会关系信息和拓扑特征可以明显增强各层网络协议功能、性能和安全特性而使其成为新的研究热点。主要研究基于在线社会网络的网络协议增强机制,在分析现有增强机制特点的基础上,对它们进行了分类。然后,深入分析了各类增强机制的关键技术,总结相关研究存在的不足,最后提出一种集成社会感知平面的网络协议增强模型。  相似文献   
163.
Formal approaches to the design of interactive systems rely on reasoning about properties of the system at a very high level of abstraction. Specifications to support such an approach typically provide little scope for reasoning about presentations and the representation of information in the presentation. In contrast, psychological theories such as distributed cognition place a strong emphasis on the role of representations, and their perception by the user, in the cognitive process. However, the post-hoc techniques for the observation and analysis of existing systems which have developed out of the theory do not help us in addressing such issues at the design stage. Mn this paper we show how a formalisation can be used to investigate the representational aspects of an interface. Our goal is to provide a framework to help identify and resolve potential problems with the representation of information, and to support understanding of representational issues in design. We present a model for linking properties at the abstract and perceptual levels, and illustrate its use in a case study of a ight deck instrument. There is a widespread consensus that proper tool support is a prerequisite for the adoption of formal techniques, but the use of such tools can have a profound effect on the process itself. In order to explore this issue, we apply a higher-order logic theorem prover to the analysis. Received May 1999 / Accepted in revised form July 2000  相似文献   
164.
Software development is rarely an individual effort and generally involves teams of developers collaborating to generate good reliable code. Among the software code there exist technical dependencies that arise from software components using services from other components. The different ways of assigning the design, development, and testing of these software modules to people can cause various coordination problems among them. We claim that the collaboration of the developers, designers and testers must be related to and governed by the technical task structure. These collaboration practices are handled in what we call Socio-Technical Patterns.

The TESNA project (Technical Social Network Analysis) we report on in this paper addresses this issue. We propose a method and a tool that a project manager can use in order to detect the socio-technical coordination problems. We test the method and tool in a case study of a small and innovative software product company.  相似文献   
165.
由于受到"艺术至上论"和"技术至上论"两种不良教学思想的影响,使得我国高校服装设计教育出现毕业学生综合素质较差,学生知识结构单一,设计思路狭窄,与社会实际需求脱节现象严重等等弊端,我们要不断深刻反思,加以改进。  相似文献   
166.
隐喻认知是一种普遍的认知机制,其应用为推进软件界面从专业走向日常生活,从效率优先到注重体验的转变发挥了重要的作用。在儿童教育和语言应用等儿童相关领域,隐喻的认知特点也获得研究人员的肯定,并积累了一定的研究结果。本文简要分析了隐喻的认知原理和审美功能,从儿童构建与解读隐喻的角度,提出儿童隐喻性人机界面设计过程中应注意的一些环节。  相似文献   
167.
本文根据认知心理学的相关理论,阐述了"心智模型"的概念,并基于心智模型的理性特征,分析讨论了传统图形设计、界面设计中遇到的视觉元素排序问题,以期为指示性的图形设计提供另一个与符号学不同的理性化的视角和依据。  相似文献   
168.
Zlatev  Jordan 《Minds and Machines》2001,11(2):155-195
Minds and Machines - This article addresses a classical question: Can a machine use language meaningfully and if so, how can this be achieved? The first part of the paper is mainly philosophical....  相似文献   
169.
By transforming the personal computer into a communication appliance, the Internet has initiated the true home computing revolution. As a result, Computer Mediated Communication (CMC) technologies are increasingly used in domestic settings, and are changing the way people keep in touch with their relatives and friends. This article first looks at how CMC tools are currently used in the home, and points at some of their benefits and limitations. Most of these tools supportexplicit interpersonal communication, by providing a new medium for sustaining conversations. The need for tools supportingimplicit interaction between users, in more natural and effottless ways, is then argued for. The idea of affective awareness is introduced as a general sense of being in touch with one's family and friends. Finally, the KAN-G framework, which enables affective awareness through the exchange of digital photographs, is described. Various components, which make the capture, distribution, observation and annotation of snapshots easy and effortless, are discussed.  相似文献   
170.
Content analyses of research published in the 1982 volumes of the Journal of Personality and Social Psychology indicate that social psychologists have largely failed to study subjects drawn from meaningfully defined social groups, to consider social structural variables, to study genuine social interaction, to observe social influences on psychological functioning, or to ask Ss about social issues. It is maintained that with few exceptions, personality researchers have failed to study groups other than college students, to use biographical materials or personal documents, to devise appropriate experimental treatments, to study persons over time, or even to retain the individual as a unit of analysis. Currently, the 2 fields of social and personality psychological research appear to be linked mainly by their deficiencies and appear to have little content worth sharing. Reexamination of each field's traditions and priorities is urgently needed. (22 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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