空调室外机用膨胀螺栓的强度计算

简要阐述了膨胀螺栓的工作原理及受力分析,介绍了膨胀螺栓的强度计算方法及原则,为恰当的选择膨胀螺栓的尺寸提供了理论依据.     

Moments and limiting distribution of a portfolio of whole life annuity policies

A dual random model of a portfolio of variable amount whole life annuity is set with themth moment of the present value of benefits, and the respective expressions of the moments under the assumption that the force of interest accumulation function is Wiener process or Ornstein-Uhlenbeck process. Furthermore, the limiting distribution of average cost of this portfolio is discussed with the expression of the limiting distribution under the assumption that the force of interest accumulation is an independent increment process.     

论长拳和楷书中的力与势

中国武术与书法,是我国的传统文化,一武一文,交相辉映,光彩夺目。长拳与楷书是其中的代表之一。那么长拳与楷书之间又存在着哪些联系,文章运用文献综述、访谈、逻辑分析等研究方法,研究得出,在练习长拳与书写楷书时,二者在力道和势道上存在着共通性联系,并进行了一些分析。     

从动作技能及其创新谈高职教育的实践教学环节

学校培养的学生。不仅应该具有丰富的科学知识,而且要掌握熟练的技能。不仅要善于“动脑”,也应该善于“动手”。本文结合教育心理学中动作技能及其形成理论谈谈对高等职教实践环节中一些问题的看法。     

高一学生力学概念理解调查研究

通过应用＂力的概念测试＂（FCI）对高一学生进行了测试和访谈,发现学生在运动学、牛顿第一定律、牛顿第二定律、牛顿第三定律、叠加原理和力的种类这六个维度的理解存在不少问题,绝大部分学生未能达到基本掌握牛顿力学概念的水平;对学生存在的主要问题进行了具体分析及教学反思,提出了以探究性教学为主要方式的概念教学建议。     

The Force Concept Inventory as a Measure of Students Conceptual Coherence

The Force Concept Inventory (FCI) is a multiple choice test designed to monitor students’ understanding of the conceptual domain of force and related kinematics (Hestenes et al. Physics Teacher 30:141–158 1992; Halloun et al., 1995, Online at http://modeling.asu.edu/R&E/Research.html). It has gained wide popularity among both researchers and physics instructors in the United States and elsewhere. The FCI has also been criticized, and its validity as a measure of the coherence of a student’s understanding of the force concept has been questioned. In this paper we provide a characterization of students’ conceptual coherence and a way to evaluate it using the FCI. We divide students’ conceptual coherence into three aspects: representational coherence (the ability to use multiple representations and move between them), contextual coherence (the ability to apply a concept across a variety of contexts), and conceptual framework coherence (the ability to fit related concepts together, i.e. to integrate and differentiate between them). Postinstruction FCI results and interview data from two Finnish high school groups (n=49 total) are discussed; the data provide evidence that the FCI can be used to evaluate students’ conceptual coherence—especially contextual coherence—of the force concept.     

JRB-2型机器人的力信号采集系统

本介绍JRB-2型机器人的控制系统的组成，并重点阐述了该机器人系统中力信号采集系统的实现。     

我国公共服务市场化的力场分析

力场分析是一种分析改革环境和确定可选择的改革行动方案的方法,它从正反两方面分析问题,识别改革环境中的抑制力量和促进力量,并将这些信息组织起来,来确定改善环境的最佳方法。据此,对我国公共服务市场化的抑制力和促进力作进一步分析,可以得出我国公共服务市场化改革的对策组合。     

Educational software for improving learning aspects of Newton’s Third Law for student teachers

In this paper, we present the design, development, implementation and evaluation of educational software “Newton-3”, aiming at the learning of Newton’s Third Law by student-teachers who are not Physics majors. We describe the theoretical issues of our teaching approach and the various software tasks that we designed in order to promote students’ understanding. Specifically, the software is designed for the teaching of gravitational and electrostatic interactions between two distant bodies at rest. It is a web-based application and runs on a simple web browser with Macromedia Flash plug-in installed. The development of software and its integration into teaching–learning sequence is based on three main characteristics: the range of contexts in which the concept of force interaction applies, in the specification of the concept, and in an appropriate teaching learning environment (IDRF). We trialled the software on two groups of 8 primary school and 8 pre-school student-teachers, for 3 teaching periods, in the School of Education of our University. The research results indicate that the implementation was effective as the majority of the teacher-students improved their own knowledge concerning the existence and representation of gravitational and electrostatic interactions. An interesting result reveals that student-teachers have difficulty in perceiving the equality of magnitudes of action and reaction forces. This problem seems to be overcome after the teaching of the Inverse square law.