成渝地区双城经济圈核心城市的博弈分析与对策研究——以交通物流基础设施建设为例

推进成渝地区双城经济圈建设已经上升为国家发展战略.以交通物流基础设施建设为例,从个体理性和团体理性两个方面,对竞争状态、合作状态和混合状态三种情况分别构建博弈关系模型并求解,得出结论:在成渝地区双城经济圈建设交通物流基础设施的过程中,核心城市的个体利益大于团体利益,表现为个体理性与团体理性之间的冲突,即两者存在非合作博弈关系.最后针对核心城市存在的非合作博弈关系,提出促进成渝地区双城经济圈核心城市协同发展的对策建议.     

Scan Statistics on Enron Graphs

We introduce a theory of scan statistics on graphs and apply the ideas to the problem of anomaly detection in a time series of Enron email graphs. Previous presentation: Workshop on Link Analysis, Counterterrorism and Security at the SIAM International Conference on Data Mining, Newport Beach, CA, April 23, 2005. Carey E. Priebe received the B.S. degree in mathematics from Purdue University in 1984, the M.S. degree in computer science from San Diego State University in 1988, and the Ph.D. degree in information technology (computational statistics) from George Mason University in 1993. From 1985 to 1994 he worked as a mathematician and scientist in the US Navy research and development laboratory system. Since 1994 he has been a professor in the Department of Applied Mathematics and Statistics, Whiting School of Engineering, Johns Hopkins University, Baltimore, Maryland. At Johns Hopkins, he holds joint appointments in the Department of Computer Science and the Center for Imaging Science. He is a past President of the Interface Foundation of North America—Computing Science & Statistics, a past Chair of the Section on Statistical Computing of the American Statistical Association, and on the editorial boards of Journal of Computational and Graphical Statistics, Computational Statistics and Data Analysis, and Computational Statistics. His research interests are in computational statistics, kernel and mixture estimates, statistical pattern recognition, statistical image analysis, and statistical inference for high-dimensional and graph data. He was elected Fellow of the American Statistical Association in 2002. John M. Conroy received a B.S. in Mathematics from Saint Joseph's University in 1980 and a Ph.D. in Applied Mathematics from the University of Maryland in 1986. Since then he has been a research staff member for the IDA Center for Computing Sciences in Bowie, MD. His research interest is applications of numerical linear algebra. He is a member of the Society for Industrial and Applied Mathematics, Institute of Electrical and Electronics Engineers (IEEE), and the Association for Computational Linguistics. David J. Marchette received a B.A. in 1980, and an M.A. in mathematics in 1982, from the University of California at San Diego. He received a Ph.D. in Computational Sciences and Informatics in 1996 from George Mason University under the direction of Ed Wegman. From 1985–1994 he worked at the Naval Ocean Systems Center in San Diego doing research on pattern recognition and computational statistics. In 1994 he moved to the Naval Surface Warfare Center in Dahlgren Virginia where he does research in computational statistics and pattern recognition, primarily applied to image processing, text processing, automatic target recognition and computer security. Dr. Marchette is a Fellow of the American Statistical Society. Youngser Park received the B.E. degree in electrical engineering from Inha University in Korea in 1985, the M.S. degree in computer science from The George Washington University in 1991, and had pursued a doctoral degree there. From 1998 to 2000 he worked at the Johns Hopkins Medical Institutes as a senior research engineer. Since 2003 he is working as a research analyst in the Center for Imaging Science at the Johns Hopkins University. His research interests are clustering algorithm, pattern classification, and data mining.     

Education for Operational Research. A Practitioner's Viewpoint

University education for operational research in Britain is making great and welcome strides forward, but there has been little open discussion of its aims in relation to the advance of the profession. Progress in operational research, and in its application to the really worth-while problems of industry in particular, depends primarily on strengthening the industrial operational research group in its “front line” role. We need a research study of the teaching and practice of industrial operational research, in relation to effectiveness. We need “collaborative” programmes of operational research education in which the university and the industrial operational research group each contribute, in a man's training over a period of years, in the ways in which each is most competent. We need emphasis on “breadth” as well as “depth” in operational research education, and greater attention to the mutual contributions of operational research, teaching and practice, and the teaching and development of management. An impressionist sketch of a programme which might meet these needs is put forward for discussion of principles and feasibility.     

Interpretations of National Curricula: the case of geometry in textbooks from England and Japan

This paper reports on how the geometry component of the National Curricula for mathematics in Japan and in one selected country of the UK, specifically England, is interpreted in school mathematics textbooks from major publishers sampled from each country. The findings we report identify features of geometry, and approaches to geometry teaching and learning, that are found in a sample of textbooks aimed at students in Grade 8 (aged 13–14). Our analysis raises two issues which are widely recognised as very important in mathematics education: the teaching of mathematical reasoning and proof, and the teaching of problem-solving. In terms of the teaching of mathematical reasoning and proof, our evidence indicates that this is dispersed in the textbook in England while it is concentrated in geometry in the textbook in Japan. In terms of the teaching of mathematical problem-solving and modeling, our analysis shows that it is more concentrated in the textbook from England, and rather more dispersed in the textbook from Japan. These findings indicate how important it is to consider ways in which these issues can be carefully designed in the geometry sections of future textbooks.     

An overview of the gender factor in mathematics in TIMSS-2003 for the Asia-Pacific region

This paper highlights the gender factor in the Trends in Mathematics and Science Study in 2003 (TIMSS-2003) of eight participating countries from the Asia-Pacific region: Chinese Taipei, Hong Kong-SAR, Indonesia, Japan, Republic of Korea, Malaysia, Singapore, and the Philippines (Chinese Taipei and Hong Kong-SAR will be referred to as countries in this paper.) in mathematics. The focus is on gender-related data encompassing the overall performance of students from the participating countries and their performance in the content and cognitive domains. At grade 8 level, the gender difference in the overall performance of students mirrored the international average and favored girls in all countries of the Asia-Pacific region (except in Japan and the Republic of Korea). The regional data also showed that, in general, the Philippines and Singapore can be considered to be at one extreme with gender differences favoring girls in both content and cognitive domains, and the Republic of Korea and to some extent Japan are at the other extreme with the gender differences favoring boys. At grade 4 level, girls from the Philippines and Singapore also performed better than the boys whereas the boys from Japan and Chinese Taipei did slightly better than the girls.     

Socio-economic and cultural mediators of mathematics achievement and between-school equity in mathematics education at the global level

This paper aims at identifying and understanding how and to what extent socioeconomic and cultural factors mediate mathematics achievement and between-school equity in mathematics education among countries. First, under the assumption that equity and quality of education are independent constructs, the construct of equity-in-quality in mathematics education is developed. Second, the 18 countries that were identified in the previous work of the author Jurdak in (Toward equity in quality in mathematics education. Springer, New York, 2009) as being diverse in mathematics education will serve as study cases to illustrate, compare, and contrast the mediatory role of socio-economic and cultural factors in mathematics achievement and between-school equity in mathematics education. The results show that the differences in mathematics achievement and between-school equity in mathematics education at the country level are associated with, and can be accounted for in some cases, by socioeconomic and cultural factors.     

商科型高校理工类研究生创新能力的培养

目前,研究生教育处于我国高等教育的最高层次,肩负着为国家发展培养高技术专业型人才的重要任务.尤其是在各国竞争愈发激烈的今天,理工类研究生更是在未来国家现代化建设、科技创新中发挥着重要作用.但是,由于近几年研究生招生规模的逐渐扩大,研究生的培养模式、培养质量等方面出现了许多亟待解决的问题.从商科型高校理工类研究生的培养现状出发,通过运用文献法和归纳法,本文对当前研究生培养过程中存在的问题进行分析,并针对学生创新能力的培养,从学校、导师和学生自身三方面给出了相应的解决措施,着重强调了数学建模在理工类研究生创新能力培养过程中所发挥的重要作用.最后,以湖南工商大学近几年在理工类研究生创新能力培养实践中所采取的主要举措以及取得的成效来进一步论证本文所提出措施的有效性.     

创业企业控制权模式选择研究

创业企业家和风险投资家因为控制权模式不合理所导致的矛盾在我国普遍存在。为解决该问题,本文通过研究创业企业家与风险投资家在博弈过程中的控制权策略选择及由此决定的控制权模式,运用演化博弈理论中复制动态的方法分析发现:(1)创业企业家和风险投资家在选择是否争取控制权的博弈结果是联合控制或相机控制;(2)项目成功概率、风险投资家获取的剩余索取权增加时收敛于联合控制,反之则收敛于相机控制;当项目成功的概率大于50%时,固定收益减少收敛于联合控制,创业企业产出增加收敛于联合控制,反则收敛于相机控制。最后,通过CV Source数据库样本数据对模型结论进行了实证检验,检验结果与理论模型的主要结论相一致。研究结论对于指导我国创业企业控制权模式合理选择具有一定的实践意义。     

The antiplane problem of the motion of a point shear load over a two-layer elastic base at a constant velocity

The problem of modelling the motion of a force disturbance in an elastic medium that is heterogeneous over its depth is investigated. It is in an antiplane formulation in a moving system of coordinates that all possible versions of the ratio of the velocity of motion of the surface point shear load to the velocities of the shear waves in the layers of the two-layer elastic base are examined. Cases of a subsonic regime (SBR) in the upper and lower layers, of a supersonic regime (SPR) in the upper layer and an SBR in the lower layer, and of an SBR in the upper layer and an SPR in the lower layer are studied using the Fourier transform and the theory of residues. The last two cases are extremely interesting from the mathematical point of view, as here, on the boundary between the layers, the solutions of elliptic and hyperbolic equations meet, and previously unknown features arise in the displacements that,it seems, should also occur in the solution of the corresponding plane problem. The case of an SPR in the upper and lower layers is investigated using a special method for successive allowance for the incident, reflected and refracted shock wave fronts. In all cases, expressions are obtained for the displacements in the layers, and their characteristic features are investigated.     

强化学习在运筹学的应用:研究进展与展望

强化学习已经成为人工智能领域一个新的研究热点,并已成功应用于各领域,强化学习将运筹优化领域的很多问题视为序贯决策问题,建模为马尔可夫决策过程并进行求解,在求解复杂、动态、随机运筹优化问题具有较大的优势。本文主要对强化学习在运筹优化领域的应用进行综述,首先介绍了强化学习的基本原理及其应用于运筹优化领域的研究框架,然后回顾并总结了强化学习在库存控制、路径优化、装箱配载和车间作业调度等方面的研究成果,并将最新的深度强化学习以及传统方法在运筹学领域的应用研究进行了对比分析,以突出深度强化学习的优越性。最后提出几个值得进一步探讨的研究方向,期望能为强化学习在运筹优化领域的研究提供参考。     

Developing Middle School Students' Interests in STEM via Summer Learning Experiences: See Blue STEM Camp

It is a well‐known fact that, in general, many students have a lack of interest and proficiency in mathematics and science. Therefore, it is imperative that we prepare and inspire all students, specifically students of underrepresented populations, to learn science, technology, engineering, and mathematics (STEM) content. Now in its fourth year, See Blue STEM Camp was created in order to expose middle‐level students to a variety of STEM fields and STEM professionals through hands‐on project‐based learning experiences in order to increase their interest in STEM. This paper describes the structure and the activities of the camp. In this innovative project, we utilized an embedded mixed methods study design to investigate the extent middle level students' attitudes, perceptions, and interest in and toward STEM fields and careers changed after participating in an informal learning environment of a five‐day day camp held on the campus of a major university in the mid‐south. The results revealed an increase in their motivation and interest in STEM fields; in fact, there was 3% increase from pre to post in interest in STEM careers. The data also revealed that a majority of the participating middle school students found the STEM content sessions “fun” and engaging, specifically citing the hands‐on experiences they received.     

The Integration of Science,Mathematics, and Technology in a Discipline-Based Culture

The culture of the middle years of schooling in Western Australia, as in many parts of the world, is predominantly discipline based. This paper focuses on exceptions to this norm by describing examples of integrated teaching of science, mathematics, and technology in seventh- to ninth-grade classrooms. Several different forms of integration were found in the 16 Western Australian schools examined in this study, including thematic approaches, cross-curricular approaches, technology-based projects, and local community projects. Interviews with teachers in these schools raised several implementation issues, including the process of getting started, implications for teachers and students, implications for schedule structure, and implications for departmental structure. All the forms of integration observed in this study were through secondary means, in which the discrete subject discipline boundaries were being maintained. The deep culture of subject disciplines, underwritten by curriculum documents organized in terms of subjects, means that there may be few incentives for teachers to teach and students to learn in an integrated manner.     

基于改进DEA——以复相关系数为基准的滞后期的我国产业结构演化效率评价

为了评价我国的产业结构演化效率,本文构建了我国产业结构演化评价指标体系。针对传统DEA方法的局限性,文中引入以复相关系数为基准的滞后期,解决了产业结构演化评价中投入和产出之间的滞后性问题,建立更加有效的DEA改进模型,对我国产业结构演化效率进行评价。结论表明,各产业技术效率大部分时间大于规模效率,而且投入要素出现不同程度的冗余情况,近年来,第一、二产业固定资产投资和就业人员冗余程度有减轻的趋势,第二产业能源和水资源消耗较大,同时第三产业各要素冗余程度均有所加深。针对这一现象,本文提出了相关对策建议。     

A Relational Perspective on Issues of Cultural Diversity and Equity as They Play Out in the Mathematics Classroom

In this article, we present a relational perspective in which cultural diversity is viewed as a relation between people's participation in the practices of different communities. In the case at hand, the relevant practices were those of students' local, home communities, and the broader communities to which they belonged in wider society on the one hand and the specifically mathematical practices established by the classroom community on the other hand. In the 1st part of the article, we discuss how we might characterize the practices of these various communities by drawing on Wenger's (1998) notion of a community of practice and on Gee's (1997) notion of a Discourse. In doing so, we question the manner in which students are frequently classified exclusively in terms of the standard categories of race and ethnicity in investigations of equity in mathematics education. Later in the article, we clarify that in addition to focusing on the continuities and contrasts between the practices of different communities, the relational perspective also encompasses issues of both power and identity. As we illustrate, the gatekeeping role that mathematics plays in students' access to educational and economic opportunities is not limited to differences in the ways of knowing associated with participation in the practices of different communities. Instead, it also includes difficulties that students experience in reconciling their views of themselves and who they want to become with the identities that they are invited to construct in the mathematics classroom.     

On the integrals of some differential equations of the Fuchs type occurring in problems of fluid and gas mechanics

We consider a linear differential equation of the Fuchs class with six singular points corresponding to the problem on a conformal mapping of circular polygons in polar grids with two cuts, which arise in the theories of filtration, jets and cavitation, fluid and aero dynamics, gas dynamics, etc. We show that, by virtue of the specific properties of polygons in polar grids, the unknown constants in the conformal mapping, which are contained in the coefficients of that equation, can be completely determined in the course of the construction of special solutions. The integrals are expressed in closed form via special functions and are hence most simple and convenient for the subsequent application.     

Sphene bearing gneisses of Madhugiri area,Karnataka State,India

Sphene fleck granitic rocks (Titanitflecken-gesteine) composed of biotite and migmatitic gneisses are frequently found in the granitic terrain between Madhugiri and Koratagere. The detailed field and thin section studies of these rocks indicate that sphene is formed during the migmatization and feldspathization of the amphibolites, which has resulted in the recrystallization of plagioclase and in the breakdown of hornblende and biotite. The released lime, titania and iron have resulted in the formation of sphene, seen in the gneissic rocks as trains, patches and discrete crystals. Mineralogical, petrological and petrochemical evidences are given in support of the above conclusion.     

中国对外直接投资的贸易效应研究:基于对北美自贸区、欧盟、东盟投资的比较分析

中国对外贸易发展成熟、国际地位显著,但从长期看,其边际收益呈现递减趋势.而对外直接投资虽规模较小,且尚在起步阶段,但其发展速度快、市场潜力巨大.在拓展Anderson和Wincoop模型基础上,理论分析了对外直接投资与贸易之间的关系.然后通过建立计量模型,利用1995-2011年面板数据进行固定模型分析.由于中国对外直接投资的贸易效应存在明显的区域性,以北美自贸区、欧盟和东盟作为研究对象,实证检验了中国对外直接投资与贸易的关系,旨在考察中国对三种不同类型区域一体化组织投资的贸易效应差异.研究结果表明,从长期看,中国对北美自由贸易区、欧盟和东盟投资均具有明显的贸易创造效应.这种贸易创造效应的大小依次是东盟欧盟北美自贸区.     

矿区土壤中含水率及重金属迁移转化的数值模拟

本文基于由连续性方程和达西定律所推出的土壤中水分运动基本方程,以一维垂向水分方程为研究对象,构造稳定收敛的有限差分格式,运用MATLAB数学工具,对地面饱水情况下土壤水分运动的一维垂向方程进行了数值模拟,得到了土壤中水分的迁移规律;同时,综合考虑对流扩散作用以及土壤对重金属的吸附解吸作用,利用非饱和土壤中重金属离子迁移转化模型,对锌离子在矿区土壤中的迁移转化进行了数值模拟,展示了锌离子在矿区土壤中的浓度分布规律．     

Subjective Assessments and Objective Yardsticks: A Contribution to Risk Theory Inspired by the Philosophy of the East

The difference between the hope of expectation and mathematical hope, as pointed out by Daniel Bernoulli in 1738 and by Harald Westergaard in 1876, and its influence on the discussion of utility is considered.The subjective elements and the objective factors in cases of risks are taken up. A digest for the evaluation of major hazards as seen from the three viewpoints, the individual, relations between individuals and the relations between individual and surroundings, is discussed.As essential elements in the decision process, the importance of voluntary and involuntary risk, pareto optimization, the size of solidarity, the absolute size of the damage and the distrust of experts is pointed out in the paper in the evaluation of major hazards-in other words, a simultaneous application of multi-decision strategies, e.g. Bayes, min-max and Hurwitz criteria.The number of members standing shoulder-to-shoulder in the group is emphasized as a numerical factor in the evaluation.     

The effect of different representations on Years 3 to 5 students’ ability to generalise

Over the past 3 years, in our Early Algebra Thinking project, we have been studying Years 3 to 5 students’ ability to generalise in a variety of situations, namely, compensation principles in computation, the balance principle in equivalence and equations, change and inverse change rules with function machines, and pattern rules with growing patterns. In these studies, we have attempted to involve a variety of representations and to build students’ abilities to switch between them (in line with the theories of Dreyfus in Advanced mathematical thinking. Kluwer, Dordtrecht, pp. 25–41, 1991, and Duval in Proceedings of the 21st conference of the North American chapter of the international group for the psychology of mathematics education, vol. 1, pp. 3–26, 1999). The studies have shown the negative effect of closure on generalisation in symbolic representations, the predominance of single variance generalisation over covariant generalisation in tabular representations, and the reduced ability to readily identify commonalities and relationships in enactive and iconic representations. This presentation will use a variety of studies to explore the interrelation between verbal and visual comprehension of context and generalisation. The studies showed in a variety of contexts the importance of understanding and communicating aspects of representational forms which allowed commonalities to be seen across or between representations.