Transnational Mathematics and Movements: Shiingshen Chern, Hua Luogeng, and the Princeton Institute for Advanced Study from World War II to the Cold War

This paper reconstructs,based on American and Chinese primary sources,the visits of Chinese mathematicians Shiing-shen Chern陈省身(Chen Xingshen)and Hua Luogeng华罗庚(Loo-Keng Hua)4 to the Institute for Advanced Study in Princeton in the United States in the 1940s,especially their interactions with Oswald Veblen and Hermann Weyl,two leading mathematicians at the IAS.It argues that Chern’s and Hua’s motivations and choices in regard to their transnational movements between China and the US were more nuanced and multifaceted than what is presented in existing accounts,and that socio-political factors combined with professional-personal ones to shape their decisions.The paper further uses their experiences to demonstrate the importance of transnational scientific interactions for the development of science in China,the US,and elsewhere in the twentieth century.

The Realistic Review on Elementary School Mathematics Teaching Reform

It is of benefit to the development of the elementary school quality-oriented mathematics education to deepen the elementary school mathematics classroom teaching reform and review the fruits of classroom teaching. In this paper, the author, with his own teaching practice, has summarized and reviewed the fruits of elementary school classroom teaching reform in four respects： 1） ＂integration of theory with practice＂ should be highlighted in this reform; 2） the classroom teaching should focus on the improvement of students＂ ＂mathematical thinking ability＂;3） mathematics classroom teaching should conform to the reality of our daily life; and 4） mathematics classroom teaching should help the students to build the ＂mathematical model thinking＂.

Experimental and Numerical Study of Wave-Induced Long-Shore Currents on A Mild Slope Beach

The long-shore current distribution on a mild slope beach is studied by combining the numerical model and the physical experiment. The experiments of long-shore currents under the action of regular and irregular waves are conducted on mild beaches with different slopes in a wave basin. A numerical model is established, which includes a wave propagation model, a wave breaking model and a long-shore current model. The validity of the numerical model is proved by the comparison of its results with the results of the experimental model. It is concluded that the wave-ioduced long-shore current is influenced significantly by the incident wave height, the wave angle and the beach slope. Its application to the Bohai Bay indicates that the wave-induced currents have the same order of magnitude as the tide currents in the near-shore zone of mill slope beach. In the design of wastewater ouffall locations on a mild-slope beach with shallow water of the Bohai Bay, the position of the outfall should be 10 km away from the shoreline, which is outside of the surf-zone.

Improvements to the fuzzy mathematics comprehensive quantitative method for evaluating fault sealing

Fuzzy mathematics is an important means to quantitatively evaluate the properties of fault sealing in petroleum reservoirs.To accurately study fault sealing,the comprehensive quantitative evaluation method of fuzzy mathematics is improved based on a previous study.First,the single-factor membership degree is determined using the dynamic clustering method,then a single-factor evaluation matrix is constructed using a continuous grading function,and finally,the probability distribution of the evaluation grade in a fuzzy evaluation matrix is analyzed.In this study,taking the F1 fault located in the northeastern Chepaizi Bulge as an example,the sealing properties of faults in different strata are quantitatively evaluated using both an improved and an un-improved comprehensive fuzzy mathematics quantitative evaluation method.Based on current oil and gas distribution,it is found that our evaluation results before and after improvement are significantly different.For faults in＂best＂and＂poorest＂intervals,our evaluation results are consistent with oil and gas distribution.However,for the faults in＂good＂or＂poor＂intervals,our evaluation is not completelyconsistent with oil and gas distribution.The improved evaluation results reflect the overall and local sealing properties of target zones and embody the nonuniformity of fault sealing,indicating the improved method is more suitable for evaluating fault sealing under complicated conditions.

Optimization Study on a Single-cylinder Compressed Air Engine

The current research of compressed air engine（CAE） mainly focused on simulations and system integrations. However, energy efficiency and output torque of the CAE is limited, which restricts its application and popularization. In this paper, the working principles of CAE are briefly introduced. To set a foundation for the study on the optimization of the CAE, the basic mathematical model of working processes is set up. A pressure-compensated valve which can reduce the inertia force of the valve is proposed. To verify the mathematical model, the prototype with the newly designed pressure-compensated intake valve is built and the experiment is carried out, simulation and experimental results of the CAE are conducted, and pressures inside the cylinder and output torque of the CAE are obtained. Orthogonal design and grey relation analysis are utilized to optimize structural parameters. The experimental and optimized results show that, first of all, pressure inside the cylinder has the same changing tendency in both simulation curve and experimental curve. Secondly, the highest average output torque is obtained at the highest intake pressure and the lowest rotate speed. Thirdly, the optimization of the single-cylinder CAE can improve the working efficiency from an original 21.95% to 50.1%, an overall increase of 28.15%, and the average output torque increases also increases from 22.047 5 N · m to 22.439 N · m. This research designs a single-cylinder CAE with pressure-compensated intake valve, and proposes a structural parameters design method which improves the single-cylinder CAE performance.

Developing a Computer Program for Detailed Study of Planing Hull＇s Spray Based on Morabito＇s Approach

Recently, Morabito(2010) has studied the water spray phenomena in planing hulls and presented new analytical equations. However, these equations have not been used for detailed parametric studies of water spray around planing hulls. In this paper, a straight forward analysis is conducted to apply these analytical equations for finding the spray geometry profile by developing a computer program based on presented computational process. The obtained results of the developed computer program are compared against existing data in the literature and favorable accuracy is achieved. Parametric studies have been conducted for different physical parameters. Positions of spray apex are computed and three dimensional profiles of spray are examined. It is concluded that spray height increases by an increase in the speed coefficient or the deadrise angle. Ultimately, a computational process is added to Savitsky's method and variations of spray apex are computed for different velocities. It is shown that vertical, lateral, and longitudinal positions of spray increase as the craft speed increases. On the other hand, two new angles are defined in top view and it is concluded that they have direct relation with the trim angle. However, they show inverse relation with the deadrise angle.

Experimental study of the movement of control fluid in compound perforation

The interaction between the high pressure gas and the control fluid and the movement mechanism of the control fluid in compound perforation were studied by a series of large-scale experiments, where the movement behavior of the control fluid was observed. The curves of measured pressure were analyzed, a mathematical model for the rigid movement of the control fluid was established, and the movement velocity of control fluid was analyzed. Moreover, the velocity from experimental results and velocity from an analytical solution were contrasted. The movement of the control fluid in the initial stage was similar to the rigid movement; however, the propagation of the pressure wave in the control fluid should be taken into account. Experimental results are significant for research on the movement mechanism of control fluid in compound perforation.

数学学科核心素养导向下的教育数学实证研究

教育数学实验是中国教育改革的重要组成部分,学生的数学学科核心素养发展状况是其改革实验效果的重要衡量指标之一.研究选取初中数学核心素养评价框架,对邛崃市教育数学实验进行评价研究,分析该实验对学生数学核心素养发展的影响.基于所选框架对该市2017级初三第二次诊断试卷考查的数学核心素养进行分类.根据学生核心素养的得分,对比分析该市3672名初三学生与93名教育数学实验班学生数学核心素养的发展状况.研究发现:该市初三学生的整体数学核心素养发展不平衡,特别是在数学建模、逻辑推理素养上不合格比例较高;教育数学体系下的实验组核心素养发展情况普遍优于该市整体水平,且其发展更为均衡.结论说明教育数学可促进学生数学核心素养的普遍均衡发展,实验风险可控,适合大规模普及.

On the Modern English Picture Book in the Teaching of English Reading in Lower Grades of Elementary School

Nowadays, more and more educators have affirmed that picture book plays an important significance in the development of children and thought that reading picture book is indispensable to the education of lower grades of elementary school.However, the teaching of reading in English, most teachers have not realized the satisfactory teaching effect, it is necessary to analyze the theoretical basis of English picture book and its application in the teaching of English reading in lower grades of elementary school and dig its value.

统计活动过程视角下小学“统计与概率”教材内容的分析与比较——以“苏教版”“北师版”为例

以“统计活动过程”视角为理论基础,从统计活动过程的各环节要素对苏教版和北师版小学数学教材中“统计与概率”内容进行分析和比较.研究发现:两版教材在统计活动过程的各环节上有所侧重,整体上各具风格;两版教材均直接突出对统计基础知识的重视,并间接蕴涵着对数据意识的培养.对教材使用的启示有:以“统计活动视角”为基础,注重对教材进行创生;将活动视角与统计教学间的“冲突”化为提升素养的机会;进而在统计活动中促进批判性思维的发展.对教材编写或修订提供启发:从学科角度厘清“统计”与“概率”的本质关系,整体把握统计活动的全过程,给予学生更多获取直接经验的机会.

加拿大小学数学教育的改革愿景与现实路向

国际视野下对不同国家学科教育与教学的讨论可以为新课改的推行提供经验借鉴和反思.加拿大小学数学课程改革突显融通学习领域与跨学科关联,课程期望关注回归基础和培养积极的数学学习者,重视教师深度理解课程标准,课程设计自主性大的愿景设计.在课堂教学上呈现出灵活设计学习任务和注重思维可视化,重视情境创设和联系生活,倡导学习评价与教学过程相结合,以及注重独立、安全学习环境创设的现实特征.中国新一轮义务教育课程改革下的小学数学课程实施,要发挥数学课程的前瞻性,重视教师对课程标准的深度理解和课程实践,创设开放包容的教学生态,充分发挥学科育人功能.

小学数学教材中“角的度量”单元内容编排分析与比较——以人教版、北师版和浙教版为例

文章从教材编排体系、教学内容以及习题设置三个维度对人教版、北师版和浙教版小学数学教材中“角的度量”单元相关内容的共性与差异性进行分析,发现其在教材内容编排方面均呈现递进式逻辑,习题设置注重思维开拓,以图形辅助文字表述的方式进行问题表征,问题结构以半开放型为主。人教版与北师版关于角的相关知识单元分布于第一、二两个学段,浙教版则集中于第二学段。教学内容上,人教版强调支架式教学,北师版注重生活经验,浙教版抽象度高。在习题设置方面,三版教材依次具备知识点涵盖面广、操作活动丰富、重逻辑推理的特点。教师可采用整合单元内容、丰富情境素材选取、直观操作与抽象概括相结合、优化习题设置等方式提升教学效果。

小学教育专业毕业生数学教学胜任力研究——以江西省某本科师范院校为例

教学胜任力是衡量小学教育专业教育质量的重要指标。通过对毕业于地方性本科师范院校的小学数学教师调查发现,不同性别、不同年龄、不同教龄、不同学历、不同专业以及不同职称的数学教师教学胜任力水平存在差异,且总体发展水平一般。应通过构建科学的专业课程体系、落实教育见习和教育实习总要求、加强教师职后培训、提升教师职业追求等措施来提升小学数学教师教学胜任力的整体水平。

论汉语语言、思维和学术模式的同构

汉语、汉人思维和传统的语言研究模式之间有内在联系。汉语的语言单位是由其周边单位确定的,汉语的产出是一个确定周边关系的过程。思维单位(概念)是以周围环境来确定认识对象,以类比求同的。传统的汉语、汉字研究就是用周边语言、文字单位来阐释语音、词义的。汉语的语言、思维、研究模式形成同构关系。

线上线下混合式教学实施方案设计——以“离散数学”课程为例

针对“离散数学”课程在传统教学模式下存在的问题,利用线上线下混合式教学的设计方法,从必要性和可行性方面进行了分析,对课前、课中、课后等环节的操作方式做了初步探讨,并实施了相应教学方案。课前环节包括视频制作和任务单设计两部分,设计了将手写讲解和PPT讲解融合的教学视频设计方案,以及四模块任务书体系。课中环节依托腾讯视频、超星、Edu Coder、WPS投屏等增强了互动功能。课后环节设计了三维度的练习体系,在时间维度设有即时、课后、章节练习,在内容维度设有开放、客观、编程练习,在手段维度设有自查、互改、教师批阅练习。通过比较实验组和控制组的成绩,证明改革取得了明显的效果。

基于新课标的“小学数学跨学科主题学习教学案”

基于小学数学跨学科主题学习教学设计研究与教学实践,形成了“小学数学跨学科主题学习教学案”研究成果,为一线小学数学教师进行跨学科主题学习教学设计和实施提供有章可依、有径可循、有本可用的有效支持。

《小学数学与语文学科整合案例研究》成果报告

在小学数学和语文教学整合研究中凝练出小学数学和语文学科整合的“四四五”教学模式,即在教学导入、情境创设、巩固练习、课后实践四环节中融入语文元素;用歌诀提升数学学习兴趣,用统一句式设计数学习题,用课文资源拓展数学学习视野,用童话故事优化数学内容四种方式;使数学与语文在口语表达、阅读积累、写作路径、逻辑思维五种场景中相融合。

广西小学生数学学习韧性现状与对策探研

数学学习韧性是学生在数学学习过程中面临学习困难或压力时有效应对和积极适应的能力,能促进学生学习能力的发展及成长成才。调查发现,广西小学生数学学习韧性处于中等偏上水平,但学习管理能力较低;农村小学生数学学习韧性显著低于城镇小学生;六年级学生的个人毅力低;留守学生的数学学习韧性差。基于此,应注重家校齐抓共管,培养自我管理学习习惯;师生互助帮扶,缩小城乡教育资源差距;渗透挫折教育,塑造学生坚毅品格;多方协同努力,关爱与帮助留守儿童。

“义务教育数学课程标准”比较研究的回顾与展望

通过对197篇“义务教育数学课程标准”比较研究文献的梳理与分析发现,中国“义务教育数学课程标准”的比较研究可分为横向和纵向两种研究类型,横向研究包括中国内地、中国香港、中国澳门、中国台湾和国际不同国家与地区之间义务教育阶段数学课程标准的比较研究,纵向研究主要针对近20年来中国内地相邻不同版本的“义务教育数学课程标准”.“义务教育数学课程标准”的比较研究以定性研究为主流形式,多选择“课程内容”板块为比较主题,初中学段的比较研究关注度较为稳定.未来相关研究应增强学科关联、加强学段联系并4003增进实践互动,以提升“义务教育数学课程标准”比较研究的理论价值与实践意义.

基于统计过程的小学生“数据意识”培养探索

统计素养应是人们身处这个数据时代所必备的素养之一,而在大部分研究者看来,这一素养的养成需要建立在统计过程之上。从学生学习统计的角度出发,研究认为,统计过程应该包括问题与目的、数据收集、数据整理与表示、数据分析与解释、判断与决策五个方面。基于此,作为统计素养中的组成部分“数据意识”来说,它的培养需要突显真实性、选择性、交互性、批判性以及反思性等要义。鉴于此,“百分数”内容在“新课标”中的变化使其具有培养小学生“数据意识”的代表性,且在统计过程之下,研究认为可以通过基于真实情境引发统计问题、联结已知选择合适统计量、借助多元表征理解统计量、运用统计量对话判断与决策以及反思统计过程留有学习余地来促进“数据意识”的培养,进而为小学阶段相关统计内容的教学提供参考。