浅析大型展会活动消防安全保卫工作

本文通过对大型展会活动火灾危险性进行总结,分析了大型展会消防安全保卫工作困难原因,有针对性地提出加强大型展会活动消防保卫工作的对策。     

α-戊(己)基肉桂醛的合成

采用聚乙二醇 ( PEG 2 0 0 )作相转移催化剂 ,用氢氧化钾醇水溶液代替氢氧化钾醇溶液合成了 α 戊 (己 )基肉桂醛 ,收率提高到 85%以上。用此工艺合成的产品纯度高 ,香气好 ,具有较高的工业实用价值。     

信息化教育 明天会更好

2007年7月21日至23日，我们参加了在重庆举办的“2007中国国际教育信息化应用论坛”，深切感受到了中国信息技术教育“百家争鸣，百花齐放”的喜人局面，以及广大教育工作者们“不断开拓、勇于进取”的奉献精神。我们每一年都参加论坛，与众多国内外专家进行交流，今年更是获益良多。     

SF6金属封闭开关设备在储运及安装中应考虑的问题

众所周知，SF6金属封闭开关设备以其结构紧凑，不受环境影响，维护工作量小，插接结构灵活等特点为广大用户所欢迎；但因其内部各元件设计是以在SF6气体中工作为设计前题，所以从储存到未完全安装就位这段时间里，其各导体元件均处于异常工作状态，如要保证其原有设计要求，就必须保护储运中的薄弱环节。     

企业诚信经营浅议

以大量史实分析了国内外企业经营的诚信问题，诚信经营在企业发展中的重要性以及如何健全企业诚信机制等相关问题，并呼吁各商家企业严格遵守企业诚信经营准则。     

Ring piezoelectric transducers radiating ultrasonic energy into the air

Ring piezoelectric transducers generating ultrasonic energy in air were designed and tested experimentally and numerically. The radiation pattern of the transducer is very narrow (4 degrees ) and its frequency response has a broadband character. Resonant frequencies of the transducers were determined experimentally and verified theoretically. Applications of the proposed ring transducers in a robotic ranging system were examined.     

Translational motion compensation for coronary angiogram sequences

A method of compensating for the lag of the video cameras typically used in angiographic systems is presented for use in sequences of digitized X-ray images. The lag effect is reduced by a straightforward weighted subtraction, which has the undesirable side effect of increasing noise. By superimposing several lag-corrected and appropriately shifted images, however, the signal-to-noise ratio can be restored. The algorithm uses the phase-correlation method to measure the two-dimensional shift of a mobile coronary arterial structure. Processing is confined to a rectangular area of interest (AOI), which encloses a feature of clinical significance. The differences of the phases of the Fourier transforms of two frames is computed, combined with an appropriate filter, and inverse Fourier-transformed to produce a phase-correlation image. The vector separation from the origin of image space of the peak of the phase-correlation image is the estimate of the shift of the artery's position in the second frame as compared to the first. The isolation of the AOI from the surrounding image is achieved by the application of a window and correction for any linear trend in the background intensity.