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1.
大功率CO2激光器脉冲电源研究   总被引:1,自引:0,他引:1  
本文论述了直流高压与高频脉冲电源相叠加,构成高频、高压脉冲电源,并使其对CO2激光器进行放电实验,研究了同条件下的放电参数与功率。  相似文献   
2.
低频电脉冲采油技术是通过升压、整流、充电等电路将电能蓄积在电容器中,通过触发电路,使能量瞬时释放,在井内液体中产生震动波,作用于地层,改善地层的渗流状况,达到提高采收率的目的。Ⅰ型设备在双河油田应用11井次,成功率72%;Ⅱ型设备在古城油田应用10井次,成功率90%。主要是由于Ⅰ型设备关键部件在处理油井时要放在井下,受高温、高压的影响及井下空间的限制,设备稳定性差、寿命短、能量小、效果差;Ⅱ型设备解决了上述问题,从而提高了试验成功率。  相似文献   
3.
关于广义函数δ(x)的讨论   总被引:1,自引:0,他引:1  
本文应用《电气子教学学报》之邀约而写,旨在针对一些读者对该韩过去刊出的有关广义函数δ(x)的文章中的质疑,从数学角度提供一些有助于正确认识、处理和运用广义函数的辅助材料。  相似文献   
4.
光纤复合架空地线雷击断股的分析及试验   总被引:4,自引:2,他引:2  
介绍了光纤复合架空地线(0PGW)雷击断股的特征,讨论了其原因和机理,并进行了0PGW的雷电冲击电波试验,分析了造成断股的影响因素,提出了防止雷击造成0PGW断股的措施。  相似文献   
5.
The transit time of the coolant, and thus its velocity, has been measured using the temperature fluctuation at the outlet of a reactor core. An impulse response function estimation is introduced, which substitutes the widely used cross-correlation measurement technique. It is shown in theory and practice that the time delay estimation is improved when using the impulse response function instead of the cross-correlation function in parameter estimation. Extremely low velocities (down to 2 cm/sec) have been measured in a natural circulation regime in a research reactor.  相似文献   
6.
According to the recent analysis results of temporary ac overvoltage in the ac system connected with a frequency converter station, large-magnitude over-voltages were confirmed to occur under some special system conditions. Most of the station insulators currently used cannot withstand such overvoltages according to an evaluation based on the data obtained earlier. The necessity of tests to be done to evaluate such performance more accurately was recognized. Both power frequency and switching impulse overvoltage flashover tests were made on contaminated insulators by the method well simulating the natural wetting condition. Switching impulse flashover voltage with the waveshape having a long wavefront time of 2 ms can be well correlated with the flashover voltage characteristics of temporary ac overvoltage. Higher flashover voltage characteristics were obtained by a clean fog test method compared with those obtained by equivalent fog test method.  相似文献   
7.
On the basis of a great number of experiments, it is proved that the strength of concrete is improved greatly when it is mixed with activated water produced by the electro-hydraulic impulse.With the proper parameters, the compression strength of concrete can be increased by 45% .The reason for improvement of concrete strength by using activated water is discussed from the aspect of the structure of molecule.  相似文献   
8.
A detection-theoretic analysis of the auditory localization of dual-impulse stimuli is described, and a model for the processing of spatial cues in the echo pulse is developed. Although for over 50 years "echo suppression" has been the topic of intense theoretical and empirical study within the hearing sciences, only a rudimentary understanding of its mechanisms has emerged. In this article, psychometric functions and results from matching studies are used in developing a model that specifies the perceived position of the echo pulse as a normal deviate, with an expectation that is a logistic function of the echo delay and a variance that depends on interaural time difference. Loss of information in the echo event is quantified as a decline in the efficiency with which the binaural system receives information from the lag impulse. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
9.
A new technology is considered for realizing the motion of solid body in the loose material due to alternating pulse ejections of compressed gas in the regime of traveling wave near the outer surface of the body. The dimensionless parameters are determined for scale modeling. The relation between the action factors and the value of motion is established empirically.  相似文献   
10.
A Novel UWB Pulse Shape Modulation System   总被引:5,自引:1,他引:4  
In this paper novel modified Hermite polynomial functions for use in impulse radio (ultra-wideband) communications are proposed. With these functions pulse shapes which are orthogonal and have nearly constant pulse width regardless of the pulse order are generated. These properties hold under the effects of differentiation. An M-ary communication system is constructed using these pulse shapes. A Matlab model for generating the pulses is designed and the effect of timing jitter on the performance of the system is investigated by computer simulation.  相似文献   
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