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排序方式: 共有177条查询结果,搜索用时 15 毫秒
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小波滤波器在弱信号检测中的应用及设计 总被引:3,自引:1,他引:2
根据小波变换的多尺度分解特性,构造了一种小波能量积累器,将不同分解尺度上的能量进行积累。在此基础上设计了一种用于弱信号检测的小波能量检测法,并对低信噪比信号的检测进行了仿真实验。仿真结果表明,该检测法对低信噪比信号是比较有效的,而且与传统的脉内累加平均的信号检测方法相比,文中提出的信号检测方法具有一定的优越性。 相似文献
133.
论甩挂运输与汽车列车总长的量化分析 总被引:1,自引:0,他引:1
道路货物甩挂运输是物流运输发展的必然趋势,但如何保证随机联接的汽车列车,其总长在法律规定的限值之内是问题的关键,为此提出了一种汽车列车总长限值符合度的量化分析模型。 相似文献
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Diego Iannuzzi Flavio CiccarelliDavide Lauria 《Transportation Research Part C: Emerging Technologies》2012,21(1):321-337
The installation of stationary ultracapacitor storage devices, as widely recognized, allows the recovery of the braking energy for increasing the energy efficiency as well as a better pantograph voltage profile. In the paper a new methodological mean is proposed for determining the fundamental characteristics of this kind of storage device, characterized by high power density, interfaced with the railroad by a bidirectional dc-dc converter. More specifically, the parameters of the storage system can be determined by employing an optimization technique which in a quite general way is able to take contemporaneously into account several aspects in an integrated manner. Some considerations are performed for properly taking into account the stochastic aspects of the design procedure. Numerical simulations with respect to a case study are presented, pointing out the potentiality of the tailored technique. Experimental results are also reported, with reference to an electromechanical simulator, in order to put in evidence the effectiveness and the actual implementation of the proposed optimization technique. 相似文献
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This paper presents an investigation of a new method of purifying cryogenic liquid using sintered metallic wire-mesh filter, which has the advantages of high purifying efficiency and preferred strength at absolutely low temperature. Experiments are conducted to purify solid CO2 particles from liquid nitrogen. Temperature and pressure in the upstream and downstream of the filter, and the flow rate of carbon dioxide (CO2) gas and liquid nitrogen are measured, with the gas content of filtrate analyzed using a CO2 concentration detector. It is illustrated that after filtration, the purity of liquid nitrogen (volume fraction) is higher than 99.99%, which means that the volume fraction of CO2 is less than 0.01%. Effects of operation parameters on the performance of the filter, such as pressure drop △p and filtration efficiency E are analyzed quantitatively. The present conclusions will provide a guideline to the optimumal design and operation of sintered metallic wire-mesh filter in cryogenic application. 相似文献
139.
冲孔灌注桩有许多优点,但在施工中容易出现问题。以洋山深水港区三期出港闸口工程为例,对可能影响或桩质量的原因进行分析。从监理的角度陈述了搞好质量监控的措施。可供参考。 相似文献
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