"物流配送中心选址的随机数学模型"的有效性研究

从实际应用出发，对文献[1]中提出物流配送中心选址的随机数学模型进行了有效性分析。通过计算机模拟得到的数据，分别应用随机数学模型和传统选址方法对不同规模的配送网络进行选址，通过分析两者在不同条件下的总费用，得到了该随机模型的一些有趣的性质，为实际中的应用提供了依据。     

投资决策中信息服务的研究

在一定假设条件下,建立了投资者对信息服务的价值分析和最佳投资的理论模型,并对文[1]中的结论进行修正,得到了与实际更加符合的结论.     

最优数学模型筛选法确定流量系数的经验公式

应用简单的最小二乘回归分析原理对多个数学模型进行分析,得到了水利工程中有坎宽顶堰流量系数的经验公式,并对其精度进行了讨论.对指导实际工程意义重大.     

飞行器定位误差的统计分布

本文研究飞行器飞行过程中的定位误差,通过对试验数据的分析,利用统计理论结合软件探求了误差的分布,得到了比较满意的结果,这一研究对实际应用有着比较重要的意义。     

基于遗传算法的水泵机组优化调度研究

从供水系统整体优化和能量损耗最小的角度出发,结合供水厂生产的实际特点,建立了基于遗传算法的水泵机组优化组合的数学模型,并对该数学模型进行求解,得到较为满意的最优解或次优解.实际生产表明,利用遗传算法求解水泵机组优化组合的数学模型,对水泵机组进行优化调度,取得了良好的经济效益.     

一类二阶变系数常微分方程的解及其渐近性

讨论实际问题中一类二阶变系数线性齐次常微分方程的数学模型,利用幂级数待定系数法得到了一般情况下的幂级数解的形式.在特殊条件下,对相应系统做变换,并利用变量分离法得到具有初等函数形式的解析解,并分析了在此情况下解的渐近性.最后,利用Lyaponov方法进行渐近性分析,得到了在一定条件下的收敛性结果,这个渐近性收敛结果在实际应用中是存在的,与某种特殊条件下的解收敛性相一致,从而说明了该数学模型在应用上有一定实际意义.     

解第一类算子方程的最大熵方法

对算子和右端都近似给定的线性不适定问题考虑了最大熵方法,得到了稳定性和收敛性,当最大熵解满足“源条件”时,导出了收敛率估计,考虑到实际的应用,给出了正则参数的后验选取法。特别地,得到了最大熵正则化解的一个刻画。     

关于病态线性代数方程组的一种迭代解法的收敛性

§1.对于病态常微分方程,韩天敏同志提出了一种积分方法,在我们的实际工作中,利用此法,得到了满意的结果。 对线性代数方程组     

具有风险相依结构的Bhlmann信度模型

在经典的Bühlmann信度模型中,一般假设风险之间是相互独立的.但在实际应用中,这种假设与实际不吻合.本文建立了风险相依情况下的Bühlmann信度模型,并得到了相应的非齐次与齐次信度估计.最后,对该结论与经典Bühlmann信度估计做了比较,得出较好的结论.     

利用近似数确定准确的范围

由于生活实践的需要,产生了准确数和近似数.与实际完全符合的数称为准确数;与实际接近的数称为近似数.如果给出一个准确数,那么我们会由四舍五入法得到近似数;如果给出由四舍五入法得到的近似数,那么如何求出这个近似数所表示的精确数的范围呢?     

基于GA_XGBoost模型的大学生科研能力预测问题研究

科学评价大学生科研创新能力对我国科研水平的提高具有重要意义.采用机器学习模型来预测大学生科研能力可以起到良好的效果,提出一种GAXGBoost模型来实现对大学生的科研能力预测.此模型是以Xgboost算法为基础,然后充分利用遗传算法的全局搜索能力自动搜索Xgboost最优超参数,避免了人为经验调参不准确的缺陷,最后采用精英选择策略以此确保每一轮都是最佳的进化结果.通过分析表明,所采用的GAXGBoost模型在大学生科研能力预测的结果中具有很高的精度,将此模型与Logistic Regression、Random Forest、SVM等模型进行对比,GAXGBoost模型的预测精度最高.     

普通高中教育投入绩效评估实证研究——基于江门市47所高中调查的多层数据

基于江门市47所高中调查的多层数据,运用多层统计分析模型,进行普通高中教育投入绩效评估的实证研究,结果表明:中考成绩与学校绩效之间呈负相关态势;高考成绩最重要的决定因素是学生先前的知识储备和起始能力水平;教育经费投入对高考成绩有显著正影响;学校师资质量对提高学生学业成就有正影响;在47所学校中,有18所学校教育绩效较好,有27所学校教育绩效还有待进一步提高,相应的教育资源的配置需要进一步优化等,并提出相应的政策建议.     

The near-peer mathematical mentoring cycle: studying the impact of outreach on high school students’ attitudes toward mathematics

College students may be seen as near-peers to high school students and high school students are often able to see themselves in the college students who are but one step ahead. This nearness in maturity and educational level may place college students in a particularly powerful position when it comes to reaching out to high school students to promote higher education in math and science. In this study college students gave dynamic mathematics outreach presentations, MathShows, to minority and low-income high school students in a mid-sized public school district on the U.S. border with Mexico. The study investigated the impacts of this sort of outreach work on high school students’ attitudes towards mathematics using a mathematics attitudes survey. Results, obtained from N = 306 participants, showed statistically significant improvements in almost all components of mathematical attitudes, with less of an effect on the component of self-confidence in doing mathematics. Differences in impacts by specific student subgroups are all discussed.     

独立学院大学数学课程体系改革与实践

以华中科技大学文华学院为例,介绍了通过开设选修课、改革大学数学教学内容、改革大学数学教学方法等方式,对大学数学课程进行教学改革的一些做法和体会.通过这些改革,提高了学生学习大学数学的积极性,取得了一定的成效.     

Lack of set theory relevant prerequisite knowledge

Many students struggle with college mathematics topics due to a lack of mastery of prerequisite knowledge. Set theory language is one such prerequisite for linear algebra courses. Many students’ mistakes on linear algebra questions reveal a lack of mastery of set theory knowledge. This paper reports the findings of a qualitative analysis of a group of linear algebra students’ mistakes on a set of linear algebra questions. The paper also details an in-time intervention (a pedagogical approach) to enhance students’ understanding of linear algebra concepts through advancing their set theory knowledge. Mathematics teachers can consider similar approaches to address their students’ mistakes.     

An Exploration of a Quantitative Reasoning Instructional Approach to Linear Equations in Two Variables With Community College Students

In this exploratory study, we examined the effects of a quantitative reasoning instructional approach to linear equations in two variables on community college students’ conceptual understanding, procedural fluency, and reasoning ability. This was done in comparison to the use of a traditional procedural approach for instruction on the same topic. Data were gathered from a common unit assessment that included procedural and conceptual questions. Results demonstrate that small changes in instruction focused on quantitative reasoning can lead to significant differences in students’ ability to demonstrate conceptual understanding compared to a procedural approach. The results also indicate that a quantitative reasoning approach does not appear to diminish students’ procedural skills, but that additional work is needed to understand how to best support students’ understanding of linear relationships.     

Singleton core in many-to-one matching problems

We explore two necessary and sufficient conditions for the singleton core in college admissions problems. One is a condition on the colleges’ preference profiles, called acyclicity, and the other is a condition on their capacity vectors. We also study the implications of our acyclicity condition. The student-optimal stable matching is strongly efficient for the students, given an acyclic profile of the colleges’ preference relations. Even when the colleges’ true preference profile is acyclic, a college may be better off by misreporting its preference when the college-optimal stable mechanism is used.     

Reasoning about relationships between quantities to reorganize inverse function meanings: The case of Arya

Researchers have argued high school students, college students, pre-service teachers, and in-service teachers do not construct productive inverse function meanings. In this report, I first summarize the literature examining students’ and teachers’ inverse function meanings. I then provide my theoretical perspective, including my use of the terms understanding and meaning and my operationalization of productive inverse function meanings. I describe a conceptual analysis of ways students may reorganize their limited inverse function meanings into productive meanings via reasoning about relationships between covarying quantities. I then present one pre-service teacher’s activity in a semester long teaching experiment to characterize how her quantitative, covariational, and bidirectional reasoning supported her in reorganizing her limited inverse function meanings into more productive meanings. I describe how this reorganization required her to reconstruct her meanings for various related mathematical ideas. I conclude with research and pedagogical implications stemming from this work and directions for future research.     

Seeking mathematics success for college students: a randomized field trial of an adapted approach

Many students enter the Canadian college system with insufficient mathematical ability and leave the system with little improvement. Those students who enter with poor mathematics ability typically take a developmental mathematics course as their first and possibly only mathematics course. The educational experiences that comprise a developmental mathematics course vary widely and are, too often, ineffective at improving students’ ability. This trend is concerning, since low mathematics ability is known to be related to lower rates of success in subsequent courses. To date, little attention has been paid to the selection of an instructional approach to consistently apply across developmental mathematics courses. Prior research suggests that an appropriate instructional method would involve explicit instruction and practising mathematical procedures linked to a mathematical concept. This study reports on a randomized field trial of a developmental mathematics approach at a college in Ontario, Canada. The new approach is an adaptation of the JUMP Math program, an explicit instruction method designed for primary and secondary school curriculae, to the college learning environment. In this study, a subset of courses was assigned to JUMP Math and the remainder was taught in the same style as in the previous years. We found consistent, modest improvement in the JUMP Math sections compared to the non-JUMP sections, after accounting for potential covariates. The findings from this randomized field trial, along with prior research on effective education for developmental mathematics students, suggest that JUMP Math is a promising way to improve college student outcomes.     

浅析对数学史教育的认识与实施

数学史教育在大学数学教育中具有重要的意义.有助于学生理解数学知识的本质,培养学生的思维能力.有必要开设数学史课程或在专业课教学中渗透数学史知识;有适合学生的专门数学史教材;进行数学史教育要联系学生的数学知识,要深入浅出;要注意数学精神的宣传.