对我国背越式跳高训练中几个重要环节的探讨

本文通过文献资料法、逻辑分析法、专家座谈法等方法对背越式跳高训练中的几个重要环节进行探讨,并对训练的方法和手段针对性地提出自己的建议,为我国跳高运动的发展提供理论依据。     

热传导中的超光速佯谬

本文指出了热传导问题中一个超光速佯谬，并就此佯谬的起因和消除提出了自己的见解。     

基于Velocity的科研项目管理系统

Velocity作为apach-jakarta的项目计划之一,是一种基于Java的模版引擎。由于Velocity强制实施表示逻辑与业务逻辑的清晰划分,实现了对MVC模型的良好支持,具有比JSP等技术更多的优点。文中讨论Velocity开发模式、Portal技术及它们在科研项目管理系统中的应用。     

关于速度、加速度与位移之间标量关系的探讨

在不同几何空间中讨论了速度、加速度与位移三者之间的标量关系,对于加深物理概念的理解具有帮助作用.     

带电粒子在正交电磁场中的运动研究

讨论电子垂直入射正交电磁场时的运动状态，导出电子运动参数方程，进行极值分析。用计算机模拟电子的运动轨迹。     

GA and PSO culled hybrid technique for economic dispatch problem with prohibited operating zones

This paper presents an efficient and reliable genetic algorithm (GA) based particle swarm optimization (PSO) tech- nique (hybrid GAPSO) for solving the economic dispatch (ED) problem in power systems. The non-linear characteristics of the generators, such as prohibited operating zones, ramp rate limits and non-smooth cost functions of the practical generator operation are considered. The proposed hybrid algorithm is demonstrated for three different systems and the performance is compared with the GA and PSO in terms of solution quality and computation efficiency. Comparison of results proved that the proposed algo- rithm can obtain higher quality solutions efficiently in ED problems. A comprehensive software package is developed using MATLAB.     

风力对100m跑的影响

风力对１００ｍ比赛成绩有较大影响,而我国此方面的研究成果很少。本文总结了国外学者１０余年来在风力对１００ｍ跑成绩影响方面的研究成果,为我国教练员和运动员提供参考。     

The relationships between impact location and post-impact ball speed,bat torsion,and ball direction in cricket batting

Three-dimensional kinematic data of bat and ball were recorded for 239 individual shots performed by twenty batsmen ranging from club to international standard. The impact location of the ball on the bat face was determined and assessed against the resultant instantaneous post-impact ball speed and measures of post-impact bat torsion and ball direction. Significant negative linear relationships were found between post-impact ball speed and the absolute distance of impact from the midline medio-laterally and sweetspot longitudinally. Significant cubic relationships were found between the distance of impact from the midline of the bat medio-laterally and both a measure of bat torsion and the post-impact ball direction. A “sweet region” on the bat face was identified whereby impacts within 2 cm of the sweetspot in the medio-lateral direction, and 4.5 cm in the longitudinal direction, caused reductions in ball speed of less than 6% from the optimal value, and deviations in ball direction of less than 10° from the intended target. This study provides a greater understanding of the margin for error afforded to batsmen, allowing researchers to assess shot success in more detail, and highlights the importance of players generating consistently central impact locations when hitting for optimal performance.     

基于MEMS技术无线网络风力传感器的研制

研制了一种严酷环境下使用的无线网络测风传感器,传感器由微型风速芯片、电子罗盘和主控及旋转部件构成微型风速芯片基于拖动力及热式原理设计、采用Mitcro EhIro Mchanical System（MEMSl技术制作而戍,由微型风速芯片和电子罗盘通过感应数据配合获得所测风的瞬时风速和风向信息,气象监测环境风传感器具体工作过程,其无线主控部件接收到测试命令后,采用旋转部件将微型风速芯片旋转一周,通过对比各时刻输出信息获得max位,由风速芯片与电子罗盘解析该时刻的数据即为所测的风速和风向信息,最后由负责传输的部件传输出去经初步测试,本设计特别适合用在高山、森林等环境恶劣的无线网络气象检测站     

神经网络的特点及改进方法综述

本文在对前馈神经网络训练算法分析的基础上,阐述了标准BP算法的特点,并分析了在实际应用中存在的不足,指出了产生不足的原因,最后介绍了一些常见的改进算法,说明了进一步研究的方向。