关于发散p-级数的一个不等式

调和级数是发散的,但有与调和级数有关的一个重要极限,它的值是欧拉常数.本文对发散的p-级数作了初步探索,证明了与发散p-级数有关的一个极限的存在性,并给出了它的取值范围.     

调和级数与P级数敛散性的简单证法

关于p级数sum from n=1 to ∞ (1/n~p)的敛散性,Cohen和Knight于1979年在(Mathematic Magazine)(Vol.52(1979),No 3)中给出了一个简单的证法;本文则给出又一个简单的证法,同时本文还给出调和级数发散的一个更为简洁的证     

Wilson定理之逆的一个简短证明

Wilson定理是初等数论中的著名定理,文[1]证明了其逆定理也成立,但证明较复杂,本文用反证法给出一个简短的证明.Wilson定理之逆:若(p-1)! 1≡0(mod p),则p是素数.证明假设p不是素数,那么p一定可以分解素因数,令p1是p的一个真素因数,则1相似文献   

关于P-根基群

给出了判断一个有限群是否为p-根基群的一种方法，p-根基群的一个充要条件，以及属于p-根基块的单模的顶点的一种刻画，改进了文献[3]中的部分结果。     

关于Polak-Ribier(?)算法收敛速率的一个注记

我们直觉上可以明显感到,既然Polak-Ribiere算法远远优于最速下降法,似乎就应该能够证明其收敛速率比线性收敛更快.但Crowder & Wolfe否定了这一想法.我们发现,[1]中的这一结论是正确的,但其论述不够充分.本文改进了[1]中的例子,给出了一个新的反例.从而对[1]中的这一结论提供了一个足够充足的论据. 文献[1]中采用的方法是构造反例.他们考虑的目标函数是二次函数     

亏数零p-块的存在条件

<正> 给定有限群G的一个p-子群D,在什么条件下D是G的一个p-块的亏数群呢?这是模表示论中一个十分重要的问题。由Brauer第一基本定理,我们可以假定D是正规子群,从而进一步化为DC_G(D)/D的亏数零p-块的存在性问题.关于此间题的研究,吸引了众多的群论和模表示论工作者.但迄今进展甚微.Brauer和Fowler[1]曾经给出了存在亏数零P-块的充分条件,Tsushima[2]和wada也曾给出过类似的条件,在本文     

罗尔定理的一个证明

本文利用连续函数的极值原理、介值定理以及极限的两边夹定理,给出了罗尔(Rolle)中值定理一个简洁证明。由于该方法迴避了运用(未被编入工科高等数学教程中的)区间套原理,从而比《美国数学月刊1979(86)》发表的Hans Samelson[1]和Alexander Abian[2]的两个新证明,在我国理工科数学有关的教学实践中更为通用。特别地,本文的方法还避免了使用文[1]所引用的P.Lévy平行弦定理[3]。     

关于有穷齐次Марков链遍历性的几点注记

本文最重要的结果在于证明了:对于任一个 k×k 的随机矩阵 P,至多只需作[2lgk/lg2]+1次矩阵乘法,就可以判定 P 是否具有遍历性.(其中[2lgk/lg2]表示不超过2lgk/lg2的最大整数).其次对于[1]中关于遍历性所证明过的充分条件以及对敛速的估计,本文将给出一个比该充分条件为弱且敛速更快的证明.     

曲线拐点充分条件证明中的常见错误

文[1]给出了判别曲线拐点的两个充分条件,文[2]给出了一个充分条件,但三个定理的证明都是错误的.同时,文[1]的两个推论也是错误的.本文通过反例分析了其错因,并给出了文[1]中一个拐点充分条件的正确证明.     

Dirichlet级数所表示的整函数的(R)准确级的型

本文讨论了用Dirichlet级数表示的整函数的(R)型、(R)准确级的p-型和(R)准确级的下型,得到这些量与Dirichlet级数的系数之间的关系。所得到的关于(R)型的结果比[1]中更精确,关于(R)准确级的型和(R)准确级的p-型(p≥3)的结果分别推广了[2,3]和[5]中的结果。最后,对于(R)准确级的下型,在一定的条件下,得到了一些与(R)准确级的型相类似的结果。     

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.     

角蛋白16和17在部分表皮肿瘤中的表达和意义

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。     

政府花费改变对经济影响的理论分析

本文采用无限期内生时间偏好率模型,研究了政府花费对经济的影响.指出长期的政府花费增加可以使资本存量水平上升,消费水平下降和债券持有量上升;同时,短期分析表明政府花费增加可以减少初始投资率,增加政府债务率水平;但短期的政府花费增加同样导致资本存量水平上升,消费水平下降和债务水平的增加.     

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.     

Exploring gender factors related to PISA 2003 results in Iceland: a youth interview study

Students’ mathematical achievement in Iceland, as reported in PISA 2003, showed significant and (by comparison) unusual gender differences in mathematics: Iceland was the only country in which the mathematics gender gap favored girls. When data were broken down and analyzed, the Icelandic gender gap appeared statistically significant only in the rural areas of Iceland, suggesting a question about differences in rural and urban educational communities. In the 2007 qualitative research study reported in this paper, the authors interviewed 19 students from rural and urban Iceland who participated in PISA 2003 in order to investigate these differences and to identify factors that contributed to gender differences in mathematics learning. Students were asked to talk about their mathematical experiences, their thoughts about the PISA results, and their ideas about the reasons behind the PISA 2003 results. The data were transcribed, coded, and analyzed using techniques from analytic induction in order to build themes and to present both male and female student perspectives on the Icelandic anomaly. Strikingly, youth in the interviews focused on social and societal factors concerning education in general rather then on their mathematics education.     

Integrating design problems in mathematics curriculum: an architecture college case study

This paper reports an attempt to improve results in the mathematics course in one of the architecture colleges in Israel through practise in applications. The effect of integrating structure design problems in the calculus curriculum on students' achievements and attitudes was examined. The applied topics in the curriculum were connected to calculus topics and studied through problembased learning activities. The integrated curriculum was implemented and the learning results in experimental and control groups were assessed by means of achievement tests, attitude questionnaires and student interviews. The learning achievements in the experimental group proved to be significantly higher than in the control group. The positive impact of learning applications on motivation, understanding, creativity and interest in mathematics is indicated.     

Problem solving and Working Mathematically: an Australian perspective

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.     

火灾发生的周期性规律及其在火灾非线性组合预测模型中应用

研究火灾发生规律及发展趋势,具有实用价值.分析历年中国火灾统计数据,发现中国火灾的发生规律同时具有增长趋势性和周期波动性特征:①中国火灾从90年代开始大幅度增加,在2002年达到最大,然后逐年缓慢下降;②每年12个月呈正弦函数波动,周期为12,1、2月发生起数最大,8、9月最小.借助于M ATLAB软件,根据2000-2006年中国火灾统计数据,建立火灾的月发生起数的非线性周期性组合预测模型,预测值与实际值的平均相对误差小于0.07.研究结论为消防研究、消防部门决策提供科学依据.     

Comparing the Development of Fractions in the Fifth‐ and Sixth‐Graders' Textbooks of Singapore,Taiwan, and the USA

This research examined the presentation of fractions in textbooks used by fifth and sixth graders in Singapore, Taiwan, and the United States. The specific textbooks examined were My Pals Are Here! Maths (MPHM) in Singapore; Kung Hsung (KH) in Taiwan; and Mathematics in Context (MiC) in the USA. Results show the problems posed in MiC put more emphasis on real‐life situations than KH textbooks in Taiwan and MPHM in Singapore. Designing materials that provide opportunities to connect mathematics content with applications in real life is consistent with recommendations from professional organizations. The activities in KH and MPHM tended to emphasize procedures, while the activities of MiC focused more on conceptual understanding and less on the development of procedures. An examination of the mathematics textbooks revealed that MPHM introduced and developed fractions the earliest among the three countries investigated and the content taught in MPHM was about one grade earlier than when the same content was experienced by students in KH and MiC.