辽宁省城镇居民生活用水定额

本文分析了城镇居民生活用水的特点,介绍了辽宁省城镇居民生活用水定额制定的原则、方法。通过对全省县级以上城镇居民生活用水情况的调查,制定适合辽宁省实际情况的城镇居民生活用水定额。     

刚性圆板自由落体在水面上的冲击压力

本文对一个刚性圆板自由落体在水面上的冲击过程建立了比较精确的理论模型,并建立了相应的数值格式。计算结果与已有的实验结果符合良好,通过计算进一步给出了下落质量和下落高度对冲击压力峰值的影响。     

基于MPEG-4标准的VOD业务探讨

MPEG-4是动态图像专家组(MPEG)标准家庭中的一员，是国际化标准组织为多媒体通信制定的一种解决方案。介绍了MPEG-4支持的新功能和特点，并阐述了MPEG-4的关键技术，在此基础上对MPEG-4在视频点播业务中的应用问题进行了探讨。     

东营凹陷古近系烃源岩超压特征及分布规律

统计分析1307口探井实测压力系数和83l口探井使用的钻井液密度数据，发现东营凹陷古近系沙三段、沙四段普遍存在异常超压，超压(压力系数1．1-1．5)主要出现在2100-3500m深度，强超压(压力系数大于1．5)主要出现在2800-3500m深度。东营凹陷沙三段、沙四段主力烃源岩超压平面分布具有北高南低、东高西低的总体特点，超压主要分布在洼陷带、断裂构造带和中央背斜带上。烃源岩压力系数等值线北部陡坡带比较密集，南部缓坡带相对稀疏。生油洼陷中心附近异常高压带的分布与生油洼陷基本一致，洼陷深陷区压力系数很大，向周围斜坡和构造高部位呈辐射状逐渐减小至正常，压力分布带与洼陷、边缘斜坡和构造较高部位的欠压实与压实带发育、分布规律的一致性很好。图3表l参9     

天然气管道燃压机组的性能试验及见证

结合西气东输管道工程燃气轮机驱动压缩机组设备订货及验收中对性能试验项目的确定、工厂试验及见证过程,介绍了燃压机组性能试验项目所涉及的主要内容、执行标准、需要达到的技术指标,各种性能试验的基本情况,买方参加工厂试验见证中需要重点处理好的问题等。以期为我国其他大型长输天然气管道机组订货及试验见证工作提供借鉴。     

An observer-based robust adaptive controller for permanent magnet synchronous motor drive with initial rotor angle uncertainty

An observer-based robust adaptive nonlinear position and speed tracking controller is developed for a permanent magnet synchronous motor with initial rotor angle uncertainty. The unknown initial rotor position is treated as a constant motor parameter in the development of the controller. An incremental encoder, which provides relative position variation of the rotor, is used along with stator current signals to achieve stable control. However, the controller does not require the knowledge of motor parameters and it only assumes friction, external disturbances, and model uncertainties are bounded. By using state observers, the measurement of acceleration and load torque, which is required usually in the nonlinear controller design with high tracking performance, is avoided. The stability of the control system and tracking convergence are guaranteed using Lyapunov theory. Finally, the stability and efficacy of the proposed drive system are verified by experimental results.     

小红楼

小红楼建于1921年，是一座三层的法式小洋楼。三十年代，它被英国百代唱片公司收购，抗日战争期间，一度被日本人占有，解放后，它成为中国唱片公司的所在地，伟大的中国国歌就诞生在这里。     

Standardizing signs on bublic information in the New Coastal Area

The public information signs ( The term public information signs will be abbreviated to public signs in the following text.)in the urban areas not only offer convenience for people to move around, but also reflect the level of development and progress of those areas. It is essential to the creative development and uplifting of the New Costal Area (thereafter, NCA) to have a good understanding of its present situation with regard to its public signs, to discuss the related issues in the development, to work out a system that is up to international standard and develop its own standards in the course of implementing the national strategies on standardizing public signs.