A comparison of email networks and off-line social networks: A study of a medium-sized bank

Recently there has been a surge in the availability of online data concerning the connections between people, and these online data are now widely used to map the social structure of communities. There has been little research, however, on how these new types of relational data correspond to classical measures of social networks. To fill this gap, we contrast the structure of an email network with the underlying friendship, communication, and advice seeking networks. Our study is an explorative case study of a bank, and our data contains emails among employees and a survey of the ego networks of the employees. Through calculating correlations with QAP standard errors and estimating exponential random graph (ERG) models, we find that although the email network is related to the survey-based social networks, email networks are also significantly different: while off-line social networks are strongly shaped by gender, tenure, and hierarchical boundaries, the role of these boundaries are much weaker in the email network.     

Comparing backpropagation with a genetic algorithm for neural network training

This article shows that the use of a genetic algorithm can provide better results for training a feedforward neural network than the traditional techniques of backpropagation. Using a chaotic time series as an illustration, we directly compare the genetic algorithm and backpropagation for effectiveness, ease-of-use, and efficiency for training neural networks.     

基于LM BP神经网络的高铁建设环境中短期影响综合评价研究

根据改进过的BP人工神经网络建立了高铁建设环境中短期影响的三层前馈神经网络综合评价模型。改进过的BP神经网络算法是在传统的算法的基础上使用LM算法，即梯度法和高斯—牛顿迭代法的结合，该种方法提高了收敛速度及精确度。根据既往已经开通运营的铁路项目对生态环境影响的深入调查和研究，建立了高铁建设环境中短期影响评价的指标体系。利用长益城际铁路作为实证，使用LM BP神经网络模型得到的综合评价分值分别为0.372和0.223，表明该铁路建设对沿线环境的短期和中期影响分别为较小影响和极小影响，评价结果有效。该模型的应用可提高评价结果的客观性和准确性，为高速铁路的选线决策提供科学的评价方法。     

基于贝叶斯网络的流动妇女收入影响因素研究

文章采用贝叶斯网络来学习和构造流动妇女收入影响因素系统,通过比较不同算法下贝叶斯网络结构的差异,说明江苏流动妇女收入影响因素之间的关系,为研究复杂社会问题提供一种简便、有效的方法。研究发现,城市是影响流动妇女职业和收入的关键变量,受教育程度和培训并不直接影响流动妇女的职业和收入。     

Guanxi networks and the gatekeeping practices of communication journals in China

In China, scholarly journals are affiliated with the particular governing organizations that house them. This process of what can be characterized as danweization has given the editors of these journals almost unchallenged power, prompting the contributors to seek their favor through guanxi networks. Drawing on fieldwork and in-depth interviews with key journal editors in media studies, this paper aims to explore the configuration of guanxi networks, the dynamics of guanxi practice in the gatekeeping process, and the implications of this practice for communication scholarship. We found that guanxi functions as a multi-layered particularism to facilitate the flow of information, to advance the priority of given papers, and to increase the rate at which such papers are published. In consequence, these journals publish a disproportionate number of articles by colleagues from the same sponsoring danwei. The operation of guanxi networks is so entrenched that it raises questions about the integrity of knowledge production and academic autonomy in China.     

基于改进的BP网络数字字符识别

提出了一种基于改进的BP网络方法来实现数字字符识别.通过对BP网络的神经元的研究与学习,设计了一种结构合理,收敛速率快的BP网络.试验测试结果表明,改进的BP网络方法对印刷体数字的识别率达到了100%,对手写数字的识别率达到了98%以上.     

Pathways to Service for Older Persons

Abstract

As services for older persons continue to shift from hospital and nursing home care to greater reliance on support for care at home, the need to understand the ways older persons obtain services becomes more important. This study examines the use of home-delivered meals as a case study to gain insight into the process of service use from the recipients' point of view. It explores the research question: What are the pathways by which older persons acquire home delivered meals? Narrative analyses of structured and unstructured questions asked of thirty frail older persons suggested that the process of acquiring home delivered meals was accompanied by patterns of adjustment in shifting between independence and dependence in managing loss of physical function, and themes of isolation, loss, and abandonment. The results provide insights for social workers in providing the support needed for the role transition that service acceptance symbolizes for older adults.     

有先行者优势的确定性网络

提出了一个确定性网络模型.模型考虑了新生成节点有不同的强弱状态,用节点度刻画节点的强弱,即强节点的度比较大.通过解析计算,得到了网络的特征系数,其特点是幂律度分布、大集聚系数和幂律簇度相关性,即模型生成了一个无标度层次网络.认为网络是无标度的是由于其生成方式上的特点,越早生成的节点拥有的度越大,这与BA(Barabási-Albert)无标度网络生长方式相似.如果节点度代表了个体拥有的资源、能力及社会关系等,那么越早生成的节点度越大,恰好对应于占先策略,即先行者优势.     

基于BP的电子商务代运营竞争力评价体系研究

企业竞争力是在经营运行过程中，使自身：乏有效地向客户提供产品或服务的能力，决定着企业的市场地位和发展潜力。在电子商务代运营：竞争力要素分析的基础上，进一步将各主要竞争力要素指标细分为22个二级指标，同时基于BP神经模型对电子商务代运营商的竞争力进行评价，有助于电子商务代运营商更准确地认知自己，并根据市场需求的变化采取应对措施进行调整，更好地为传统企业进行电子商务应用提供代运营服务。