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1.
中国数学家明安图在其《割圜密率捷法》中最先应用了Catalan数,取得优秀的研究成果.本文简介明安图的计数成就和Catalan数,综述国内外对明安图应用该数的研究.特别地,近两年来英国的Larcombe发表了5篇文章,对明安图的成果——包含Catalan数的sin(2pa)展开式,加以推广,并给出明安图确定Catalan 数的第二种方法的严格代数证明.  相似文献   

2.
微积分为基础的分析数学是近现代数学发展的主流.无穷级数是其一个组成部分,在早期的发展中起了不可缺少的作用.格列高里(J.Gregory,1638—1675)、大数学家欧拉(L.Euler,1707—1783)、伯努利(J.Bernoulli,1654—1705)等对此做出了巨大的贡献.过去,人们一直认为只有西方研究了无穷级数.其实,18世纪中叶之前,清代蒙古族杰出数学家明安图也开展了这方面的研究,得到了一批有价值的成果,并创立了独具特色的证明方法——割圆连比例法.1 明安图及其数学著作明安图(1692?—1763?),生于今内蒙古锡林郭勒盟正镶白旗,我国清代著名的科学家.早年曾在…  相似文献   

3.
由中国科学院国家天文台施密特 CCD小行星项目组 1 999年 1月 6日在河北兴隆发现的小行星 1 999AT2 2 ,获得永久编号 :2 82 42。经国家天文台批准 ,又经国际天文学联合会小天体提名委员会审议 ,并于 2 0 0 2年 5月 2 6日批准 ,通知国际社会 ,正式将 2 82 42号命名为“明安图星”,以纪念我国清代蒙族杰出的科学家明安图。明安图是蒙古正白旗人 ,据一项研究推测他的生卒年是 1 692— 1 763年 ,是清代卓越的天文学家和数学家。幼年入选八旗官学 ,学习天文、数学。1 71 3年学成留在钦天监 (即今天文台 )工作 ,先后参加了 4项大型天文书的编写 …  相似文献   

4.
罗见今  沙娜 《高等数学研究》2009,12(4):124-128,F0003
徐光启、利玛窦1607年所翻译的<几何原本>前6卷对清代数学的发展产生了深刻的影响.本文列举3项案例,对梅文鼎的理分中末线、明安图的无穷级数、李善兰的积分公式等标志性成果进行具体分析,认为这些成就的获得除了传统数学的影响外,程度不同地受益于<几何原本>.  相似文献   

5.
借用项名达易率法、借率法和明安图多项式,本文分析证明关于割圆连比例解的项氏定理,澄清了易主经法的基本原理和方法特征,揭示了易率法与借径术、还原术三者之间的关系。  相似文献   

6.
清代著名数学家董祐诚,继明安图之后研究“杜氏九术”,即三角函数的级数展开公式,他通过发现弦矢术和堆垛术之间的关系,利用中国传统数学历史悠久且成果卓著的堆垛求积术求解,方法独特,成就斐然,形成清代“九术”研究园地中的一朵奇葩。国内数学史界开始注意到他,但很少提及他的生平,对他主要著作中的思想方法  相似文献   

7.
用鞅论方法来研究多变点过程及其随机控制已引起人们注意。P.Bremaud在这方面作了许多工作.A.F.Martins-Neto与E.Wong用鞅论方法研究了排队问题.R.Boel与 P.P.Varaiya在 1977年的一篇文章中讨论了一个较为一般的跳过程最优控制模型.M.H.A.Davis与R.J.Elliott对[3]的工作作了改进,建立了跳过程最优控制的极小值原理.R.Rishel,S.R.Pliska等人用不同的方法得到类似结果.  相似文献   

8.
本文研究了短区间的并集中的D. H. Lehmer问题.利用不完全Kloosterman和的均值定理,给出了D. H. Lehmer问题的渐近公式,从而推广了短区间的D. H. Lehmer问题.  相似文献   

9.
本文是D.C.隶属函数模糊集及其应用系列研究的第一部分.建立了D.C.隶属函数模糊集的基本概念.探讨了D.C.隶属函数模糊集的基本性质和D.C.隶属函数模糊集对一些常见的重要t模、余模和伪补的封闭性.并以此建立了丰富的模糊数学应用模型.  相似文献   

10.
沈文淮 《数学学报》1989,32(3):338-344
本文讨论了 CW 复形同伦群的有关性质.推广了 C.A.McGibbon 和 J.A.Neisendorfer 的定理.  相似文献   

11.
李勇军  江莹 《运筹与管理》2021,30(11):60-64
小学教育是教育阶段的基础,也是我国强制教育的一部分。但如何在各省份性别比例相差较大的情况下,更加有效的提高各省份小学教育资源配置效率是一个值得思考的问题。为了避免性别带来的影响,可以通过平行结构DEA模型根据学生性别分为两个平行子系统,来衡量我国2012~2018年各省份小学教育的资源配置情况。研究发现大部分省份小学教育资源配置的总系统效率未达到有效边界,仍有需要改进的地方。男学生在小学教育阶段的效率通常优于女学生在小学教育阶段的效率,但随着近些年我国教育体制的日益完善,女学生在小学教育阶段的效率呈上升趋势。此外,我国西部地区的小学教育资源配置效率在一些年份普遍优于东部和中部地区,而中部地区和东部地区小学教育总系统效率相对稳定,西部地区小学教育总系统效率波动较大。  相似文献   

12.
Slope is a fundamental mathematics concept in middle and high school that transcends to the university level. An understanding of slope is needed at the university level since slope plays an important role in understanding problems involving variation and change. In this study Mexican curricula documents were examined to determine which conceptualizations of slope are addressed in the intended mathematics curriculum. To explain the results, we use conceptualizations of slope identified in previous research. Our findings reveal that, to a certain extent, the conceptualizations proposed in the Mexican intended mathematics curriculum differ slightly in terms of the emphasis and timing of instruction from what others have identified in the U.S., with slope as a geometric ratio receiving less emphasis in the Mexican curriculum. There was also noted discontinuity within the Mexican curriculum in introducing slope in grade 9 and subsequently introducing of linear functions in grade 10 without explicit mention of slope. Suggestions are made for future studies, both to consider the conceptualizations of slope promoted in the Mexican textbooks and the impact they have in classroom instruction and student learning of slope.  相似文献   

13.
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.  相似文献   

14.
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.  相似文献   

15.
There is general agreement in Australia and beyond that quantitative skills (QS) in science, the ability to use mathematics and statistics in context, are important for science. QS in the life sciences are becoming ever more important as these sciences become more quantitative. Consequently, undergraduates studying the life sciences require better QS than at any time in the past. Ways in which mathematics and science academics are working together to build the QS of their undergraduate science students, together with the mathematics and statistics needed or desired in a science degree, are reported on in this paper. The emphasis is on the life sciences. Forty-eight academics from eleven Australian and two USA universities were interviewed about QS in science. Information is presented on: what QS academics want in their undergraduate science students; who is teaching QS; how mathematics and science departments work together to build QS in science and implications for building the QS of science students. This information leads to suggestions for improvement in QS within a science curriculum.  相似文献   

16.
Preface     
We are presenting in this volume the collection of extended abstracts of 66 talks that were presented at Combinatorics 2012 in Perugia, Italy. Combinatorics 2012 is the 17th in the series of combinatorics conferences held in Italy, first in 1981, next in 1982 and every two years since then.  相似文献   

17.
This paper deals with the problematic aspect of the reconstruction of binary relations: it includes all the questions raising the possibility or impossibility to determine a structure by gathering given substructures. It is the continuation of three studies: the first made by G. Lopez [9] in 1972 about the determination of a binary relation through the types of isomorphism of its restrictions, the second made by K. B. Reid and C. Thomassen [15] in 1976 about the strongly self-complementary tournaments (every subtournament is self-complementary), the third made by C. Thomassen [16] in 1989 about the cycle space of a tournament. In the second section, we use the notion of class of difference (which was introduced in [9]) to extend a study made in [16] to binary relations. Then, in the third section, we improve the result of this last study in the case of the tournaments. After noticing that the result of [15] inferred itself naturally from the approach developed in [9], we extend, in the fourth section, the study made in [15] to binary relations.  相似文献   

18.
我国制造业背景下质量管理活动的量表开发研究   总被引:1,自引:0,他引:1  
质量管理的测度是质量管理实证研究的基础,但我国在此领域还处于起步阶段。以重庆市制造业企业为样本,采用基于偏最小二乘法的证实性因子分析方法,对我国制造业企业的质量管理活动进行了实证度量。结论显示,我国制造业企业质量管理活动包含六个方面的主要内容:企业高层的支持、员工的参与、供应商关系、重视客户、产品设计和流程管理。研究给出了具体的我国质量管理活动的测度量表。  相似文献   

19.
A mathematical model and numerical simulations corresponding to severe slugging in air-water pipeline-riser systems are presented. The mathematical model considers continuity equations for liquid and gas phases, with a simplified momentum equation for the mixture. A drift-flux model, evaluated for the local conditions in the riser, is used as a closure law. In many models appearing in the literature, propagation of pressure waves is neglected both in the pipeline and in the riser. Besides, variations of void fraction in the stratified flow in the pipeline are also neglected and the void fraction obtained from the stationary state is used in the simulations. This paper shows an improvement in a model previously published by the author, including inertial effects. In the riser, inertial terms are taken into account by using the rigid water-hammer approximation. In the pipeline, the local acceleration of the water and gas phases are included in the momentum equations for stratified flow, allowing to calculate the instantaneous values of pressure drop and void fraction. The developed model predicts the location of the liquid accumulation front in the pipeline and the liquid level in the riser, so it is possible to determine which type of severe slugging occurs in the system. A comparison is made with experimental results published in literature including a choke valve and gas injection at the bottom of the riser, showing very good results for slugging cycle and stability maps. Simulations were also made assessing the effect of different strategies to mitigate severe slugging, such as choking, gas injection and increase in separation pressure, showing correct trends.  相似文献   

20.
一个修正的PVT算法   总被引:2,自引:0,他引:2  
对Fkshima(1998)所提出的PVT算法给出一种修正算法,称为修正PVT算法,这一修正算法对PVT原算法中的并行步中的停止准则和同步步骤作了修正。修正PVT算法的停止条件对PVT原算法的停止条件弱,因此更适用于并行计算,并且计算时间比PVT原算法少。  相似文献   

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