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51.
S. Chaturvedi C. Dunne Z. Ashktorab R. Zachariah B. Shneiderman 《Computer Graphics Forum》2014,33(8):52-68
An important part of network analysis is understanding community structures like topological clusters and attribute‐based groups. Standard approaches for showing communities using colour, shape, rectangular bounding boxes, convex hulls or force‐directed layout algorithms remain valuable, however our Group‐in‐a‐Box meta‐layouts add a fresh strategy for presenting community membership, internal structure and inter‐cluster relationships. This paper extends the basic Group‐in‐a‐Box meta‐layout, which uses a Treemap substrate of rectangular regions whose size is proportional to community size. When there are numerous inter‐community relationships, the proposed extensions help users view them more clearly: (1) the Croissant–Doughnut meta‐layout applies empirically determined rules for box arrangement to improve space utilization while still showing inter‐community relationships, and (2) the Force‐Directed layout arranges community boxes based on their aggregate ties at the cost of additional space. Our free and open source reference implementation in NodeXL includes heuristics to choose what we have found to be the preferable Group‐in‐a‐Box meta‐layout to show networks with varying numbers or sizes of communities. Case study examples, a pilot comparative user preference study (nine participants), and a readability measure‐based evaluation of 309 Twitter networks demonstrate the utility of the proposed meta‐layouts. 相似文献
52.
53.
《International journal of human-computer studies》2014,72(1):126-139
Emergency planning is an ongoing activity in which a multidisciplinary group of experts intermittently collaborate to define the most appropriate response to risks. One of the most important tasks of emergency planning is the review of plans as a way of maintaining, refining, and improving them. This review of plans is based on exchanging knowledge and experiences in order to take into account different perspectives and generate alternative solutions. An exploratory case study carried out within municipal organizations has disclosed how the application of rigid plan reviewing practices hinders team creativity and, consequently, effective decision-making. This paper presents a computer-based collaborative environment aimed at supporting unstructured team discussion during the post-hoc review of emergency plan. This collaborative environment allows emergency planning team members to share their view in a free manner by interacting with user interface components distributed across several input and output dimensions. The usage of the environment has proved how the application of new interactive technologies can create more dynamic work settings, fostering team creativity. 相似文献
54.
The coupling efficiency of seven coupling agents in wood–polymer composites (WPC) was investigated in this study. The improvement on the interfacial bonding strength, flexural modulus, and other mechanical properties of the resultant wood fiber/high‐density polyethylene (HDPE) composites was mainly related to the coupling agent type, function groups, molecular weight, concentration, and chain structure. As a coupling agent, maleated polyethylene (MAPE) had a better performance in WPC than oxidized polyethylene (OPE) and pure polyethylene (PPE) because of its stronger interfacial bonding. A combination of the acid number, molecular weight, and concentration of coupling agents had a significant effect on the interfacial bonding in WPC. The coupling agents with a high molecular weight, moderate acid number, and low concentration level were preferred to improve interfacial adhesion in WPC. The backbone structure of coupling agents also affected the interfacial bonding strength. Compared with the untreated composites, modified composites improved the interfacial bonding strength by 140% on maximum and the flexural storage modulus by 29%. According to the statistical analysis, 226D and 100D were the best of the seven coupling agents. The coupling agent performance was illustrated with the brush, switch, and amorphous structures. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 93–102, 2005 相似文献
55.
Unique explanations are given to describe changes in the mixing torque and tensile and impact properties of poly(vinyl chloride) (PVC)/wood sawdust composites affected by various types and concentrations of silane coupling agents. Concentrations of 0.5–1.0 and 1.5 wt % coupling agent are recommended for the optimization of the tensile and impact properties of the composites, respectively. Changes in the tensile and impact properties of the composites with a low sawdust content were more sensitive to the addition of silane coupling agents than those with a high sawdust content. KBM603 was suitable for improving the tensile properties, whereas KBE603 is recommended for high impact resistance of the composites. The differences in the mechanical and thermal properties of the PVC/sawdust composites were dependent on the characteristics of the functional groups in the silane coupling agents used, such as hydrophilic level, number of functional groups, self‐condensation reaction, and effectiveness of the hydrolysis reaction. Silane coupling agents above 1.0 wt % resulted in an increase in polyene sequences in the PVC structure. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 213–221, 2005 相似文献
56.
旨在探讨一种新的企业知识管理体系结构及其构建方法.分析现有企业知识管理体系存在的问题,研究个人知识管理体系的结构特点及其优点,并结合蜂窝状组织结构方式,提出一种基于个人知识管理构建企业级知识管理体系的方法,并阐述其原理、特点及其构建方法.与现有企业知识管理体系相比,这种新方法使得知识的更新更加快速,系统维护更方便,具有更简便、灵活、高效的特点. 相似文献
57.
PSO-SVM模型的构建与应用 总被引:3,自引:0,他引:3
为了使支持向量机(SVM)获得更好的分类效果,针对人为选择参数的随机性,提出了利用粒子群算法(PSO)进行参数自动选取的优化方法,构建了PSO-SVM模型.在个人信用评估中,通过对粒子适应度函数的设置来控制造成较大损失的第二类误判,应用结果表明:模型在训练和测试样本中的分类精度可以达到95%,第二类误判率分别仅为0.78%和2.02%.利用PSO对SVM中的参数进行优化,可以避免人为选择的随机性,并且在解决分类问题中表现出较好的稳健性. 相似文献
58.
该文运用组合预测的思想,提出了通过感知器、BP、Elman和LVQ等不同的具有代表性的神经网络模型,将多元线性回归和logistic回归两单一方法进行组合,并分别应用于某商业银行的个人信用评估,其结果表明:感知器、BP、Elman和LVQ神经网络组合预测方法精确度不尽相同,但总体上能够获得比多元线性回归和logistic回归更高的预测精度,尤其在避免纳伪错误方面更具优势。 相似文献
59.
从社会关系抽取的角度出发,设计了一个基于主题的Web人名抽取系统。该系统可根据给定的主题获取相应的Web文档,并从中抽取出与该主题相关的中英文人名,从而为基于主题的Web社会关系抽取提供有效的数据支撑。 相似文献
60.
朱程 《浙江水利水电专科学校学报》2010,22(4):98-101
建立大学生顶岗实习人身伤害事故校方责任评估体系,明确界定事故责任,有利于妥善地处理好学生伤害事故,维护学生合法权益和学校声誉;强化学校安全责任观念,增强学校预防意识,切实保护学生的人身安全;有利于进一步实施大学生素质教育.本文提出了制订评估体系应遵循的几项原则,分析了学校对事故所负责任大小的几种类型,构建了大学生顶岗实习期间发生人身伤害时学校承担责任的评估体系. 相似文献