车用发动机噪声测试研究

采用内燃机噪声声功率级测定的工程法和简易法对湖南动力机厂的6105Q-C型车用柴油机进行了噪声声功率级的测试．测试发现，该柴油机在标定工况下的噪声声功率级为113dB(A)，已满足国际规定要求，并且低于我国中小型功率柴油机噪声限值及国内同类机型产品的噪声值．但从试验数据看，喷油泵、进气管所在端面及项面噪声辐射较显著，声压级略高；从频谱看，1000～2000Hz范围内噪声最大．本文对上述问题提出了分析与改进意见．     

电动折弯机控制系统关键技术研究

介绍了基于变频器控制的电动折弯机工作原理，开发了基于矢量控制的电动折弯机控制系统。给出了该系统的工作原理，并对决定控制系统性能的硬件和软件控制算法进行研究，最大限度地实现了硬件设备的独立性和无关性，实验结果表明系统达到精度要求，软件易于扩展，通用性好。     

冬小麦田间小气候与大气候比较研究

通过对冬小麦拔节后期、孕穗期和成熟期田间活动面和1．5m高的气温和相对湿度与标准气象站对应要素作了同步观测和分析，找出各生育时段的差异，为将公共气象信息转换成作物环境信息提供了依据。     

Windows Installer技术及其使用

Windows Installer是微软推出的软件安装、发布及管理方式，使用它可以进行包括软件的发布、安装、修改、升级、移除在内的全程管理，较好地解决了原有软件发布方式中存在的问题．本文描述了Windows Installer的特点、结构、运行过程以及实现途径，最后说明了使用它进行软件发布的基本步骤．     

快速成形技术中轮廓环的分组算法及其应用

以平面内轮廓环的存在规则和相互关系为出发点，提出了一种简单实用的轮廓环的分组算法，通过本方法对平面的轮廓环进行分组，能够把一个平面分解成一系列简单的单连通区域，分组后的轮廓环不仅能够在进行其他运算时减少重复计算，而且可以在分区填充扫描线时减少分区数，从而减少实际扫描时的空跳．     

绕线式异步电动机转子斩波串级调速系统的研究

为了克服传统串级调速系统功率因数低的缺点,提出了一种新型斩波式串级调速方案,该方案利用整流桥和IGCT构成直流斩波电路来连续无级改变电机转速,同时介绍了一种新型电力半导体器件-集成门极换向晶闸管(IGCT)的特性和工作原理. 这种方法线路简单,对系统功率因数的改善也很有效.     

工程装备的腐蚀与防护对策

叙述了工程装备在不同工作环境中的腐蚀失效形式，详细分析了其大气腐蚀、水介质腐蚀、土壤腐蚀等腐蚀形式产生的原因、腐蚀机理及行为，并从工程装备的选材和结构设计、电化学保护、施加高效防腐涂层等方面入手，制定了相应的防腐技术对策，从而达到提高工程装备使用寿命和可靠性的目的。     

A Study on the Surface Structures of Viscose-based Activated Carbon Fiber by FT-IR Spectroscopy and XPS

Using viscose fiber (VF) as starting material and common steam as activating agent, formation of oxygen structures in activated carbon fiber is investigated. In the preparation of samples, VF was first heated at temperatures between 450℃ and 900℃ in N_2 artmosphere. Then, in a successive activation stage, the product carbonized at 600℃ was activated in steam at 450-900℃ for 30 min, and at 600℃ for 5-30 min. The other carbonization products were activated at 600 and 900℃ for 30 min respectively. The products activated at 900℃ were then activated at 450℃ for 30 min again. The starting materiah carbonized products and all activation products were examined by FT-IR spectroscopy and some products were examined by X-ray photoelectron spectroscope (XPS). And the yields of the carbonized and activated products were calculated. By analysing these spectra, the amount of oxygen-containing functional groups of the activated products attained under various activation time, various activation temperature and     

Switched Capacitor Network Analysis by Means of TCM

The totally coded method (TCM) reveals the same objective law, which governs the gain calculating for signal flow graph as Mason formula does. This algorithm is carried out merely in the domain of code operation. Based on pure code algorithm, it is more efficient because figure searching is no longer necessary. The code-series (CS), which are organized from node association table, have the holoinformation nature, so that both the content and the sign of each gain-term can be determined via the coded method. The principle of this method is obvious and it is suited for computer programming. The capability of the computeraided analysis for Switched Capacitor (SCN) can be enhanced.     

Meshing Theoretical Study and Simulation on Cylindrical Tri-sine Oscillating Tooth Gear Drive

The structure of cylindrical tri-sine oscillating tooth gear drive is presented. Based on the space meshing theory, equations of meshing and tooth profile are established and its meshing theory is studied. Using Pro/E, this system is modeled and simulated,which is compared with the above-established equations.