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1.
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.  相似文献   

2.
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.  相似文献   

3.
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.  相似文献   

4.
Teachers involved in a Master's level course in diversity participated in virtual, synchronous, anonymized discussions around issues of ethnic and racial diversity, gender, and stereotypes that could impact their students’ participation in fields related to science, technology, engineering, and mathematics (STEM). Guided by theoretical frameworks from Social Cognitive Career Theory (SCCT) and Critical Race Theory (CRT), a convenience sample of 14 science and mathematics teachers participated in a series of virtual chats using open‐ended questioning and facilitated by two university instructors. Using conversation and critical discourse analyses, three primary themes emerged: understanding of issues related to stereotypes, encouragement of females and minorities to pursue careers in STEM, and the place for diversity discussions in science and mathematics classrooms. The teachers felt burdened by curricular and administrative constraints that inhibit their ability to participate in thought‐provoking critical conversations. The paper concludes with a discussion of ways teachers can assist in the STEM career identity development of their underrepresented females and students of color and calls for research that combines the key findings in SCCT and CRT to build confidence and capacity for teachers to effectively confront issues of racism, sexism, and stereotyping in science and mathematics classrooms.  相似文献   

5.
Keith Jones  Taro Fujita 《ZDM》2013,45(5):671-683
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.  相似文献   

6.
Murad Jurdak 《ZDM》2014,46(7):1025-1037
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.  相似文献   

7.
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.  相似文献   

8.
目的 研究角蛋白16 和17(K16、K17)在部分表皮肿瘤中的表达和意义。方法 采用免疫组化法检测K16、K17在正常皮肤、脂溢性角化病、日光性角化病、皮角、基底细胞癌、鳞状细胞癌中的表达。结果 K16、K17 在正常皮肤表皮各层呈阴性表达;在脂溢性角化病表皮各层中除了角质层外大多呈阳性表达;在日光性角化病表皮K16 均不表达,K17 除了角质层外在其他各层也不表达;K16 在皮角表皮棘层呈强阳性表达,但在其他各层均呈阴性表达,K17 在皮角表皮各层基本呈阳性或强阳性表达;在基底细胞癌中,K16、K17除了在棘层呈弱阳性表达外,在其他各层均呈阴性表达;在鳞状细胞癌中,K16 在基底层呈阴性表达,但在其他各层及K17 在表皮全层均呈阳性或强阳性表达。K16 除基底层外在肿瘤表皮其他各层表达比较差异均有统计学意义(均P<0.05);K17 在表皮各层表达差异均有统计学意义(均P<0.05)。结论 K16、K17的表达状况可为表皮肿瘤的鉴别诊断提供病理学方面的依据。  相似文献   

9.
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.  相似文献   

10.
Jaguthsing Dindyal 《ZDM》2008,40(6):993-1005
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.  相似文献   

11.
Comprehension of chance language, such as is found in newspapers, is a fundamental aspect of statistical literacy. In this study, students' understandings of chance language were explored through responses to two items in surveys administered to 2,726 students from grades 5 to 11. One item involved evaluating the chance expressed in phrases from newspaper headlines using a number line, and responses were described in four levels of chance language evaluation. The other item involved interpreting, in context, an expression of percent chance, and responses were described in four levels of chance language interpretation. Students in higher grades were more likely to demonstrate higher levels of both evaluation and interpretation. The association between levels of evaluation and interpretation was further explored generally and in relation to one of the headlines involving percent. Implications for mathematics educators in relation to chance language in the curriculum across the years of schooling are discussed.  相似文献   

12.
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.  相似文献   

13.
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。  相似文献   

14.
本文通过引入城镇化及居民消费等因素拓展LMDI模型,解构中国能源消费碳排放变动为碳排放因子、能源强度、消费抑制因子、城镇化、居民消费和人口规模六大效应,并探讨上述六种效应变动对中国能源消费碳排放量变动的贡献率及其作用机理。然后,选择中国30个省份,2003-2012年的面板数据实证分析人口结构变动对区域能源消费碳排放量变动及其分解效应的影响。结果表明:2003 2012年中国碳排放总量增加42.1167亿吨,消费抑制因子效应、城镇化效应、居民消费效应和人口规模效应对碳排放量的影响呈现为正效应,而碳排放因子效应和能源强度效应对碳排放量的影响整体上呈现为负效应,并且居民消费效应对碳排放量变动的影响最大。人口城镇化已成为影响中国碳排放量变动的主要人口因素。较之中、西部地区,东部地区的人口规模效应明显较高,但其能源强度效应则相反,中部地区碳排放因子效应明显高于东、西部地区。现阶段,人口年龄结构、人口教育结构和人口职业结构变动减缓了中国碳排放量的增长,而人口城乡结构、区域经济水平和人口规模变动的影响方向则相反,最后,人口性别结构变动对碳排放量变动无显著地影响。  相似文献   

15.
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.  相似文献   

16.
David Clarke  Merrilyn Goos  Will Morony 《ZDM》2007,39(5-6):475-490
This article reviews “problem solving” in mathematics in Australia and how it has evolved in recent years. In particular, problem solving is examined from the perspectives of research, curricula and instructional practice, and assessment. We identify three key themes underlying observed changes in the research agenda in Australia in relation to problem solving: Obliteration, Maturation and Generalisation. Within state mathematics curricula in Australia, changes in the language and construction of the curriculum and in related policy documents have subsumed problem solving within the broader category of Working Mathematically. In relation to assessment, research in Australia has demonstrated the need for alignment of curriculum, instruction and assessment, particularly in the case of complex performances such as mathematical problem solving. Within the category of Working Mathematically, recent Australian curriculum documents appear to accept an obligation to provide both standards for mathematical problem solving and student work samples that illustrate such complex performances and how they might be assessed.  相似文献   

17.
基于多元线性回归模型的东北地区需水量分析   总被引:2,自引:0,他引:2  
多元线性回归模型在社会、经济、技术以及众多自然科学研究领域中已被广泛使用,某个地区需水量应与该地区多种因素有关,故选取东北地区的GDP、水库蓄水总量、人均可支配收入、城市绿地面积和工业用水量等5个因素,借助MATLAB软件阐明了多元线性回归模型在东北地区需水量分析中的应用.并通过皮尔森相关性检验、拟合优度检验、F检验、t检验和残差分析的方法对模型进行优化,得到了准确可靠的多元线性回归模型,此模型具有拟合程度高、简易、直观等优势,为多元线性回归模型在需水量分析中的应用提供了有力参考.  相似文献   

18.
Mathematical commentaries in Arabic and Persian have come down to us in abundant numbers and manifoldness. There is no study of them as a literary genre, their distribution over time, space, or topic, nor of their forms or styles. The commentaries that have been scrutinized so far are few in number and focusing in topic mostly on geometry and in scope on those with innovative contributions. In this paper, I will try to survey more generally purposes, forms, and styles of mathematical commentaries based on a larger number of texts with different thematic content and range and produced in different contexts, periods, and localities.  相似文献   

19.
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.  相似文献   

20.
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.  相似文献   

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