一类二阶线性微分方程的振动性及非振动性

本文研究了二阶线性方程的振动性及非振动性问题，建立了若干新的振动与非振动性结果，它们改进并推广了若干已知的定理。     

柱面上Lienard系统闭轨的存在性与唯一性

本文研究了柱面上Ｌｉｅｎａｒｄ系统非零伦闭轨和零伦闭轨的存在性与唯一性及不存在性问题，获得了若干新结果，并举例说明了本文的结果可用于动力学及电动力学等一些重要实际问题的讨论中。     

矢值序列空间Λ[X]及其Kothe对偶(Ⅳ)──遗传性

本文是［１］的继续．就矢值序列空间Λ［Ｘ］，我们在本文中讨论了Λ［Ｘ］中的有界集，紧集，以及Λ［Ｘ］的序列弱完备性，桶性，自反性等的遗传问题．     

线性规划问题的一种转换解法

本文根据矩阵对策与对偶规划问题的等价性，以及矩阵对策的凌越原则，对线性规划问题提出了一种转换解法。     

随机环境中耦合空间的不变测度存在性

本文研究了随机环境中耦合空间上不变测度存在性问题，证明了一些存在性定理．     

关于带一般混合边界条件的半线性反应扩散系统解的整体存在性问题

本文利用Ｇｒｏｎｗａｌｌ不等式及对偶技巧，研究了带一般混合边界条件的半线性反应扩散系统解的存在性问题，给出了一些控制条件，得到解的整体存在性，改进并推广了以前的结果。     

3-D涡块边界曲面高阶正则性的传播

本文讨论了涡块问题边界曲面高阶正则性的传播，同时解决了［８］中所提出的关于边界曲面Σ０的高阶正则性的传播问题．     

一类广义KdV—Burgers型方程的初边值问题

本文研究了一类带三阶粘性项的广义ＫｄＶ－Ｂｕｒｇｅｒｓ型方程的初边值问题，运用Ｇａｌｅｒｋｉｎ逼近方法，结合能量估计，得到了问题整体解的存在性，正则性，唯一性和稳定性等结果，并在一定条件下讨论了问题的解的渐边行为和“爆破”现象。     

周期解的存在性、唯一性与稳定性

本文研究了高维周期系统的周期解的存在性、唯一性及稳定性等问题，利用指数型二分性和不动点方法，建立了保证周期解的存在性、唯一性及稳定性的充分条件，所得的结果推广了文［１、２］的主要结果。     

高维系统周期解的存在性与唯一性

本文首先利用一种新方法讨论高维系统解的一致有界性，一致最终有界性及非常稳定性问题，然后将所获结果应用于高维系统周期解的存在性与唯一性的研究。另外，本文还提出了“阶梯形系统”的概念，并对其建立了一种利用系统部分方程周期解存在性判定整个系统周期解存在性的方法。     

我国能源-环境-经济系统的区域间建模

本研究试图探讨用“自上而下”和“自下而上”相结合的建模方法,对我国二氧化硫和二氧化碳减排进行区域间建模.本研究以一个用于分析硫税的区域间波及影响、以及评价电力部门的脱硫技术的区域间可计算一般均衡模型为基础平台;从理论上探讨了如何对该模型进行扩展和改进.首先本研究对该模型的要点进行了阐述,强调了把能源技术模型融合在区域间可计算一般均衡模型中的建模方法.然后本研究对于实行环境税和排放权交易的环境经济效果进行了比较,用成本收益法分析了工业部门对减排技术的选择,并以前述模型为基础建立了区域间模型.本研究所提出的模型可以被用来从区域统筹的观点,对我国能源-环境-经济系统的可持续发展进行预测和分析.最后本研究提出应该从更新数据、研究环境政策和技术进步之间的关系等方面,进一步发展该模型.     

Homotopy and semisymmetry of quasigroups

The study of quasigroup homotopies reduces to the study of homomorphisms between semisymmetric quasigroups. In particular, the study of homotopies between central quasigroups reduces to the study of homomorphisms between entropic semisymmetric quasigroups. Received December 20, 1996; accepted in final form September 17, 1997.     

Interactive group decision-making using a fuzzy linguistic approach for evaluating the flexibility in a supply chain

With global competition rapidly intensifying and shifting to the supply chain level, the supply chain flexibility has become increasingly important. However, the literature addressing supply chain flexibility remains limited. This study thus builds a group decision-making structure model of flexibility in supply chain management development. This study presents a framework for evaluating supply chain flexibility comprising two parts, an evaluation hierarchy with flexibility dimensions and related metrics, and an evaluation scheme that uses a three-stage process to evaluate supply chain flexibility. This study then proposes an algorithm for determining the degree of supply chain flexibility using a fuzzy linguistic approach. Evaluations of the degree of supply chain flexibility can identify the need to improve supply chain flexibility, and identify specific dimensions of supply chain flexibility as the best directions for improvement. The results of this study are more objective and unbiased for two reasons. First, the results are generated by group decision-making with interactive consensus analysis. Second, the fuzzy linguistic approach used in this study has more advantage to preserve no loss of information than other methods. Additionally, this study presents an example using a case study to illustrate the availability of the proposed methods and compare it with other methods.     

中国上市公司资本结构影响因素之实证研究

资本结构不仅是财务理论研究中的热点及难点,也日益成为公司理财决策的关键问题.本文从影响因素角度对资本结构进行实证研究.文中以深沪两市部分非金融类上市公司为样本,利用本世纪最初三年的企业财务数据,选取可能影响企业资本结构的多个指标为解释变量,利用单因素方差分析、主成分分析、逐步回归分析找出了主要影响因素及其影响方式,试图为国内上市公司资本结构决定因素提供最新实证研究证据,并为企业财务决策提供支持.     

A study of resampling methods for testing equality of means in paired population

The goal of this study is to compare the resampling methods including bootstrap and permutation tests against classical methods for paired samples. A simulation study was conducted to see the performance of both parametric and nonparametric methods under various assumptions such as non-normal populations and small or large sample sizes. The results of the simulation study are with respect to type I error and power of the test.     

Pre-service science teachers’ perceptions of mathematics courses in a science teacher education programme1

Most science departments offer compulsory mathematics courses to their students with the expectation that students can apply their experience from the mathematics courses to other fields of study, including science. The current study first aims to investigate the views of pre-service science teachers of science-teaching preparation degrees and their expectations regarding the difficulty level of mathematics courses in science-teaching education programmes. Second, the study investigates changes and the reasons behind the changes in their interest regarding mathematics after completing these courses. Third, the current study seeks to reveal undergraduate science teachers’ opinions regarding the contribution of undergraduate mathematics courses to their professional development. Being qualitative in nature, this study was a case study. According to the results, almost all of the students considered that undergraduate mathematics courses were ‘difficult’ because of the complex and intensive content of the courses and their poor background mathematical knowledge. Moreover, the majority of science undergraduates mentioned that mathematics would contribute to their professional development as a science teacher. On the other hand, they declared a negative change in their attitude towards mathematics after completing the mathematics courses due to continuous failure at mathematics and their teachers’ lack of knowledge in terms of teaching mathematics.     

Reading mathematics for understanding—From novice to expert

As students progress through the college mathematics curriculum, enter graduate school and eventually become practicing mathematicians, reading mathematics textbooks and journal articles appears to become easier and leads to increased proficiency and understanding. This study was designed to begin to understand how mathematically more advanced readers read for understanding in mathematical exposition as it appears in textbooks compared to first-year undergraduate students. Three faculty members and three graduate students participated in this study and read from a first-year graduate textbook in an area of mathematics unfamiliar to each of them. The observed reading strategies of these more mathematically advanced readers are compared to observed reading strategies of first-year undergraduate students from an earlier study. The reading methods of the faculty level mathematicians were all quite similar and were markedly different from those that have been identified for undergraduate students, as well as from those used by the graduate students in this study. A Mathematics Reading Framework is proposed based on this study and previous research documenting the strategies that first-year undergraduate students use for reading exposition in their mathematics textbooks.     

纵向删失数据下线性模型的相合估计

医药临床试验,生存分析,可靠性统计等研究领域,由于考虑到时间和费用问题,研究往往有一定期限.因为研究到期的被迫结束或者某些病人中途退出试验,最后得到的试验结果往往是删失数据.对于删失数据,采用无偏转换的方法处理,方法的最大优点是得到的估计量为显式解.首先讨论了在纵向右删失数据下线性回归模型回归系数估计的均方相合性,并且把结论推广到了污染线性模型,得到了污染系数、回归系数的强相合估计.     

基于FCE的建设项目环境效益可研指标的应用——以高速公路建设项目为例

应用FCE进行建设项目环境效益可研指标体系综合评价是一条科学精简的途径.高速公路建设项目对项目沿线环境的影响典型而尖锐,以高速公路建设项目为例分析FCE在建设项目环境效益可研指标中的应用,并以福银高速公路一期工程尤溪段施工期环境效益可研为例建立应用模型.