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61.
62.
王腾  朱青  王珊 《计算机学报》2013,36(8):1668-1681
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   
63.
This study proposes a versatile criterion for estimating quality of images in electrical impedance tomography. The point spread function (PSF) is calculated throughout the domain based on the scattering of energy as responses to a small anomaly spirally moved from the centre to the boundary. The proposed PSF is a measure of weighted spatial variance (WSV) of the conductivity over the whole domain. For each element, the weighting factor is a normalized multiplication of the area of that element by its square intensity. The WSV collectively incorporates all image attributes, i.e., spatial resolution, artifact, amplitude response, positioning error and shape deformation. The location of artifacts, which significantly influences reconstructed images in reality, is taken into account as well. The results illustrate that the proposed measure is more tolerant than existing criteria in evaluating performance of EIT systems in both theory and practice.  相似文献   
64.
Evaluation on collaborative manufacturing network (CMN) structure characteristics has important implications for network operations such as production decision-making, product recovery, creating consensus. Several recent studies suggest that augmenting network structure with nodes’ attributes can provide a more fine-grained understanding of the network. However, there have been few studies to provide a systematic understanding of these effects in a CMN at scale. This gap is bridged using an industrial printing machinery CMN data-set collected on a web-based producing and outsourcing service platform. Novel phenomena with respect to both interaction and attribute metrics across and within the CMNs are observed. Moreover, although many studies employ either interaction or attribute data to study the relative roles of manufacturers in a CMN, relatively little is known about the relationship between these two types of data. This study explores this relationship by comparing two defined metrics (i.e. relational capability and node capability), which evaluate the manufacturers’ interactions and attributes, respectively. We examine to what extent the two metrics of manufacturers correlate with each other, and how possible dissimilarities and similarities can be explained based on the collected industrial CMN data-set. The insights thereby provide a better basis for efficient operations decision-making in CMN.  相似文献   
65.
The landscape conditions for forming the water balance and runoff from catchment areas can change considerably under the pressure of natural and anthropogenic factors. The role of hydromorphic transformation of landscapes is important for most of the Ob basin; it results in the paludification of the area. The specific parameter n is used in calculating water balance according to Mezentsev’s method of hydro-climatic calculations to take account of landscape conditions. We suggest determining this parameter’s value by geomorphological features of the landscapes using GIS tools.  相似文献   
66.
Mechanical cooling systems in buildings are the main producers of carbon dioxide emissions, which have negative impacts on environment and amplify global warming, particularly in hot climate. Due to the lack of energy supply, windcatchers can be utilized as a sustainable attempt for cooling and ventilation purposes. The objective of this paper is to review and provide a comprehensive literature on windcatcher system for space cooling and ventilation. The concepts were discussed according to the relevant parameters of windcatcher, i.e. windcatcher attributes, windcatcher configurations and windcatcher technologies. The pros and cons of this green architectural feature have also been highlighted and the future research need in this realm of study is proposed.  相似文献   
67.
Feature selection is very important for feature‐based relation classification tasks. While most of the existing works on feature selection rely on linguistic information acquired using parsers, this letter proposes new features, including probabilistic and semantic relatedness features, to manifest the relatedness between patterns and certain relation types in an explicit way. The impact of each feature set is evaluated using both a chisquare estimator and a performance evaluation. The experiments show that the impact of relatedness features is superior to existing well‐known linguistic features, and the contribution of relatedness features cannot be substituted using other normally used linguistic feature sets.  相似文献   
68.
以服务机器人为对象运用"语意差异法",通过实验与问卷调查的心理学研究方法,针对20个实验样本,从构成外观形态的点、线、面等造型元素的形态语义角度,着重分析了服务机器人情感体验细节的设计要素。实验证明了用户的情感体验与机器人外观形态的趣味性相关,并与构成要素形态语义的可接受程度成正比。研究结果还提供了实现服务机器人情感设计的形态构成要素:"点、线、面"的细节设计要求与设计指南。  相似文献   
69.
周栩  刘磊  范任宏 《电子学报》2011,39(4):882-886
本体映射是语义集成的关键技术,本文基于本体的模式结构提出了一种自顶向下的本体映射方法,该方法在考虑四种基本映射关系并假定所有映射关系均为1:1的情况下,首先将本体描述为图,并将本体中的每个概念都定义为树,在此基础上给出了树中叶节点、非叶节点相似度的计算方法,通过概念分类将子树进一步合并,根据分类的结果重新组织图结构,最...  相似文献   
70.
服务匹配已经成为服务计算领域的一大热点.合理的服务匹配算法可以帮助服务需求者寻找到满足自己需求的服务.在分析现有的服务算法基础上,提出基于混合语义相似度服务匹配方法MSSMA(Mix Semantic Similarity Matching Algorithm).将比较成熟的语义相似度算法和基于匹配等级的计算方法相结合,从而提高服务匹配的精度.  相似文献   
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