软件工程的历史与发展趋势

软件是一种特殊的产品,随着其规模和复杂性的提高、使用范围的扩大,需要从技术和管理两方面对软件的开发过程进行控制。从软件工程这门学科和技术出现的背景出发,回顾了软件工程在近40年来理论、方法和实践中的成果。最后结合Internet技术和平台的挑战,初步讨论了软件工程需要面对的新挑战。     

黄冈方言的后加成分"着"

在黄冈方言中,“着”可附在时间词或动词短语之后,构成具有动词性的“着”字结构,相当于“等到……以后再……”或“等到……再说”。成都方言“哆”字结构与黄冈方言“着”字结构性质相同,二之间可能存在一定的渊源关系。“哆”、“着”都不是“再说”衍生出来的;关于“着”的来源,杨永龙（2002）所说较为可信。     

Coordination pattern of baseball pitching among young pitchers of various ages and velocity levels

This study compared the whole-body movement coordination of pitching among 72 baseball players of various ages and velocity levels. Participants were classified as senior, junior, and little according to their age, with each group comprising 24 players. The velocity levels of the high-velocity (the top eight) and low-velocity (the lowest eight) groups were classified according to their pitching velocity. During pitching, the coordinates of 15 markers attached to the major joints of the whole-body movement system were collected for analysis. Sixteen kinematic parameters were calculated to compare the groups and velocity levels. Principal component analysis (PCA) was conducted to quantify the coordination pattern of pitching movement. The results were as follows: (1) five position and two velocity parameters significantly differed among the age groups, and two position and one velocity parameters significantly differed between the high- and low-velocity groups. (2) The coordination patterns of pitching movement could be described using three components, of which the eigenvalues and contents varied according to age and velocity level. In conclusion, the senior and junior players showed greater elbow angular velocity, whereas the little players exhibited a wider shoulder angle only at the beginning of pitching. The players with high velocity exhibited higher trunk and shoulder rotation velocity. The variations among groups found using PCA and kinematics parameter analyses were consistent.     

安徽R&D投入产出水平的实证分析

在国内外的研究基础上,结合安徽特有的基本情况,建立了一套评价安徽省各市R&D投入产出综合水平指 标体系,运用主成分分析和聚类分析,客观的评价了安徽省各地市R&D投入产出水平。评价结果表明,“合芜蚌”试验 区引领带动着全省R&D投入产出水平,“皖江带”城市R&D投入产出水平两极分化严重,而“皖北”地区则有崛起的势 头,从而为各市提升R&D投入产出水平提供参考依据。     

具有多连通分支的超越整函数的增长性

Let g and h be two transcendental entire functions. Suppose that the Fatou set F（goh） contains multiply connected components. In this article, we will consider the growth of the functions g and h.     

High-extensible scene graph framework based on component techniques

INTRODUCTION With the tremendous growth of the digital en- tertainment industry in the past decades, the scale of game scene is becoming more gigantic. To effectively manage and organize the massive data, game engine usually uses hierarchical scene graph. Many popular 3D modelling tools, such as Maya, 3D Studio Max, use scene graph to manage the scene content (Sowizral, 2000). 3D modelling software—Houdini directly edits scene graph to create and modify the virtual environment. Most v…     

B/S架构中基于HTML组件的WEB打印技术

一直以来B/S架构下的打印问题都是B/S系统开发中的难题,本文逐一对现有B/S架构打印方法进行了分析,针对它们的缺陷,提出丁一种基于HTML组件的更有效和更精确的打印方法,详细介绍了其原理,并给出了具体的实现方法,实践表明该方法使用效果良好.     

古文英译的历程和前景

古文英译是翻译事业的组成部分。回顾古文英译的历程、总结经验、展望未来 ,以期有助于中西文化的交流和中西外事的交往。     

浅谈初中化学新课的引入

初中化学新课的引入,可采取问题直接引入法、由实验提出问题引入法、由问题引入实验法、巧设"陷井"法等.     

义素分析法在语言教学中的功用

义素分析法在词语解释、同义词辨析、反义词对比、修辞分析中有特殊的功用，特别是对当今有些看似错误的特殊的语言现象通过义素分析，可以窥见语言发展的新动向。