Spatial Clustering Tests Based on the Domination Number of a New Random Digraph Family

We use the domination number of a parametrized random digraph family called proportional-edge proximity catch digraphs (PCDs) for testing multivariate spatial point patterns. This digraph family is based on relative positions of data points from various classes. We extend the results on the distribution of the domination number of proportional-edge PCDs, and use the domination number as a statistic for testing segregation and association against complete spatial randomness. We demonstrate that the domination number of the PCD has binomial distribution when size of one class is fixed while the size of the other (whose points constitute the vertices of the digraph) tends to infinity and has asymptotic normality when sizes of both classes tend to infinity. We evaluate the finite sample performance of the test by Monte Carlo simulations and prove the consistency of the test under the alternatives. We find the optimal parameters for testing each of the segregation and association alternatives. Furthermore, the methodology discussed in this article is valid for data in higher dimensions also.     

士人与山川——从《容美纪游》看传统士人的山川观念

《容美纪游》是一本创作于清代康熙年间的游记作品,记录了作者顾彩在清康熙四十三年（1704年）前往湖北西部、今土家族分布区的容美土司地旅行五个多月的经历。顾彩心中的容美,既是野蛮地,又是桃花源,同时还是一个仙居地。顾彩对容美土司的三重印象,正是他应对自身所处时代的产物,寄托了他对理想社会的追求。顾彩的容美之旅,反映出以顾彩为代表的中国传统士人的一种山川观念。此类山川观念,实际是中国儒家士人中久存的一个传统。在＂士志于道＂的追寻中,山川之地成为了对自身社会的一个超越,成为一个＂求道＂之地。在现今鄂西地区的土家族历史或地方史研究中,《容美纪游》被视为唯一揭示清代改土归流之前鄂西地方政治、社会、地理历史面貌的史籍资料,因此有着极其重要的地位。     

技术的整体论思考:英戈尔德的技术人类学

英戈尔德是当代英国著名的人类学家,是技术人类学领域的创立者之一。他在技术人类学领域的主要贡献是提出了以人类和非人类、技术和技能、技术和语言、社会和自然等内容为核心的技术人类学研究纲领。在此纲领基础上,英戈尔德又阐发了体现人类学整体论思维方式的技术环境观。英戈尔德的技术环境观弥合了自然与人文、技术与人类、功能与意义之间的裂痕,为技术人类学的研究提供了新的启示。     

关于移位自映射浑沌性的简化证明

本文通过构造符号空间与[0,1]的可逆对应,证明了符号空间上的移位自映射是浑沌的,简化了文[2]的证明。     

空间的凸性和远达点映射的连续性

本文给出空间严格凸、CLUB和LUR的新特征刻划,后用这些特征对中一定理作了改进.     

Reliability analysis of man–machine systems using fuzzy cognitive mapping with genetic tuning

This article offers a method for analyzing the reliability of a man–machine system (MMS) and ranking of influencing factors based on a fuzzy cognitive map (FCM). The ranking of influencing factors is analogous to the ranking of system elements the probabilistic theory of reliability. To approximate the dependence of “influencing factors—reliability,” the relationship of variable increments is used, which ensures the sensitivity of the reliability level to variations in the levels of influencing factors. The novelty of the method lies in the fact that the expert values of the weights of the FCM graph edges (arcs) are adjusted based on the results of observations using a genetic algorithm. The algorithm's chromosomes are generated from the intervals of acceptable values of edge weights, and the selection criterion is the sum of squares of deviations of the reliability simulation results from observations. The method is illustrated by the example of a multifactor analysis of the reliability of the “driver–car–road” system. It is shown that the FCM adjustment reduces the discrepancy between the reliability forecast and observations almost in half. Possible applications of the method can be complex systems with vaguely defined structures whose reliability depends very much on interrelated factors measured expertly.     

Constructing optimal router bit life sequential experimental designs: New results with a case study

Consider the experiment to improve router bit life as reported in Phadke (1986 Phadke, M. S. 1986. Design optimization case studies. AT &; T Technical Journal 65:51–68.[Crossref], [Web of Science ®] , [Google Scholar]). The goal of the experiment was to increase the life of the router bit before it gets dull, which causes excessive dust formation and consequent expensive cleaning operation to smooth the edges of the boards. A 32-run experimental design was used including seven two-level factors and two four-level factors (cf. Table 1). In this experiment and others, factorial designs with a mixture of two-level and μ( > 2)-level factors may be adopted. Sequential experiments composed of initial experiments and follow-up experiments are widely used to resolve ambiguities involving the aliasing of factorial effects. This article investigates the construction and theoretical properties of optimal designs for sequential experiments with a mixture of α two-level and β μ-level factors for the first time. Constructing optimal design for the router bit life sequential experiment will be discussed for a practical use. From the numerical results, it is found that using a uniform design as the initial experimental design for the router bit life experiment is highly recommended to get an efficient router bit life sequential experimental design. The novelty and significance of the work are evaluated by comparing our results to the existing literature.     

试论晚清武昌舆地学会的舆图出版及其经营特点

光绪二十二年（公元1896年）成立的译印西文地图公会（后改称武昌舆地学会）是中国第一个地理学会。学会用西方先进的测绘方法和印刷技术编制出版了七百余幅中外地图，在晚清地图学史上占据着举足轻重的地位。其所绘制出版的地图严谨、科学；用小比例尺绘制地图；地图表示和绘制方法新颖，并经过仔细审查修订；用新式烂铜版法印制地图，开铜版雕刻彩印出版小比例尺地图之先河。学会的经营特点是：集资招股编绘、印制地图不以投资为终极目的；购股者分次付清股票款项；以推广舆地学为务，厘清所筹股金的用途及作用，通过售书偿还股金和利息。     

开关DC-DC变换器斜坡补偿的稳定性控制研究

从混沌稳定性控制的角度研究了采用斜坡补偿的buck、boost和buck-boost开关DC-DC变换器的稳定性控制机理,建立了采用补偿斜坡的开关变换器的离散映射迭代模型,得到了开关变换器电路的稳定性判据和补偿斜坡斜率的表达式。利用分叉图、Lyapunov指数谱和时域波形图,清晰地描绘出补偿斜坡电流(或电压)对开关变换器的电路稳定性能的影响。研究结果表明,采用斜坡补偿技术能有效地改善开关DC-DC变换器的稳定性。     

国际移动公共服务研究综述

\t 目的/意义\t 近年来,移动政务和政务新媒体的发展问题作为一个新的社会热点和学术议题,引起了政府和学界高度关注和广泛讨论,从时间演化的纵向维度和国内外对比的横向维度分析移动政务研究,有助于深入了解该领域研究现状并推进移动政务研究的发展。\t \t 设计/方法\t 选择Web of Science核心数据库1911篇外文文献和CNKI核心合集571篇中文文献,运用CiteSpace 5.3对突显词、关键词和被引文献等绘制知识图谱,对比分析国内外研究的演化阶段、研究热点和知识基础。\t \t 结果/发现\t 国内外都较为关注信息技术变革、应用实践领域;国外研究更多地以用户为导向,关注研究移动政务的隐私保护与安全性,国内研究则以政策为导向,更倾向关注政府职能转变;国外研究具有成熟且丰富的理论和模型,而国内研究以定性研究为主,注重理论本土化实际。未来研究可在丰富研究视角,加强理论积累,夯实实证研究,满足公众个性化服务,深入公众采纳创新研究等领域深入展开。\t