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排序方式: 共有842条查询结果,搜索用时 203 毫秒
51.
52.
模块化多电平换流器(modular multilevel converter, MMC)子模块电容均压问题,是MMC型高压直流输电系统稳定运行的关键。当桥臂子模块数过多时,采用传统的排序均压算法将使电容电压排序运算量过大,这对控制器的硬件设计带来巨大挑战。针对传统均压算法的问题,提出了一种改进的电容电压平衡方法,通过对子模块分组,减少了电容电压排序运算量,同时采用一种组间电压平衡算法,解决了各组间电压不平衡问题。在此基础上,类比整数质因子分解思想进一步优化,得到电容电压平衡分组排序的最优化方法。在实时数字仿真器RT-L ab中搭建了模块化多电平换流器直流输电系统(modular multilevel converter high voltage direct current,MMC-HVDC)模型进行仿真验证,仿真结果表明,改进方法及最优化方法能在维持子模块电容电压平衡的同时,大大提高仿真计算速度,从而验证了所提出方法的有效性和可行性。 相似文献
53.
浅析高速公路透层、稀浆封层的质量控制 总被引:2,自引:0,他引:2
周柳卿 《江苏工业学院学报》2005,17(3):24-26
公路透层、稀浆封层技术作为一种经济有效的预防性技术手段在高速公路建设中被推广应用.总结了高速公路透层、稀浆封层的施工经验,对透层、稀浆封层的主要技术指标进行了分析,并指出了透层、稀浆封层施工后的质量通病以及确保施工质量所采取的关键措施. 相似文献
54.
Martina Rudnicki Marcos Roberto de Oliveira Tiago da Veiga Pereira Flávio Henrique Reginatto Felipe Dal-Pizzol José Cláudio Fonseca Moreira 《Food chemistry》2007,100(2):719-724
The leaves of Passiflora alata Dryander and Passiflora edulis Sims, traditionally used in American countries to treat both anxiety and nervousness by folk medicine, are rich in polyphenols, which have been reported as natural antioxidants. In this study, the antioxidant activities of P. edulis and P. alata hydroalcoholic leaf extracts were verified in in vitro and ex vivo assays. P. alata showed a higher total reactive antioxidant potential than did P. edulis. The antioxidant activities of both extracts were significantly correlated with polyphenol contents. In addition, both extracts attenuated ex vivo iron-induced cell death, quantified by lactate dehydrogenase leakage, and effectively protected against protein damage induced by iron and glucose. These findings demonstrate that the P. alata and P. edulis leaf extracts have potent in vitro and ex vivo antioxidant properties and might be considered as possible new sources of natural antioxidants. 相似文献
55.
Hot electrons emitted from thin oxide film-coated heavily doped silicon electrodes by cathodic pulse polarization can induce electrochemiluminescence from luminophores. The intensity of electrochemiluminescence produced at the electrode surface is dependent on the features of thin oxide films formed by thermal oxidation. As a preliminary study, we investigated the effect of thermal oxide growth conditions on the intensity of electrochemiluminescence produced at these electrodes, such as oxidation atmospheres, oxidation temperature, oxidation time and pre-treatment of wafers, using ruthenium(II) tris-(2,2′-bipyridine) chelate as a model luminophore. Optimal oxidation conditions of heavily doped silicon electrodes were obtained for the generation of intense electrochemiluminescence at this kind of silicon electrodes. 相似文献
56.
57.
We clarify the notion of a strong prime by supplying a precise definition and a characterization for an optimal strong prime. We present a conjecture regarding the distribution and density of optimal strong primes, allowing one to predict in advance the time needed to compute one optimal strong prime of a given bit length. Based on these results, we develop an algorithm to compute optimal strong primes. Some experimental results are also included. 相似文献
58.
59.
Fault diagnosis of full-scan designs has been progressed significantly. However, most existing techniques are aimed at a logic
block with a single fault. Strategies on top of these block-level techniques are needed in order to successfully diagnose
a large chip with multiple faults. In this paper, we present such a strategy. Our strategy is effective in identifying more
than one fault accurately. It proceeds in two phases. In the first phase we concentrate on the identification of the so-called
structurally independent faults based on a concept referred to as word-level prime candidate, while in the second phase we further trace the locations of the more elusive structural dependent faults. Experimental results
show that this strategy is able to find 3 to 4 faults within 10 signal inspections for three real-life designs randomly injected
with 5 node-type or stuck-at faults.
Part of this work has ever appeared in the proceedings of Asian Test Symposium in 2003.
Yu-Chiun Lin received his BS degrees in Electrical Engineering from National Central University in 2000, and MS degree from Electrical
Engineering of National Tsing Hua University in 2002. Since then, he has been with Ali Corporation as a design engineer. His
current interests include the design of USB controllers and imaging periperals.
Shi-Yu Huang received his BS, MS degrees in Electrical Engineering from National Taiwan University in 1988, 1992 and Ph.D. degree in Electrical
and Computer Engineering from the University of California, Santa Barbara in 1997, respectively. From 1997 to 1998 he was
a software engineer at National Semiconductor Corp., Santa Clara, investigating the System-On-Chip design methodology. From
1998 to 1999, he was with Worldwide Semiconductor Manufacturing Corp., designing the high-speed Built-In Self-Test circuits
for memories. He joined the faculty of National Tsing-Hua University, Taiwan, in 1999, where he is currently an Associate
Professor. Dr. Huang’s research interests include CMOS image sensor design, low-power memory design, power estimation, and
fault diagnosis methodologies. 相似文献
60.
How to select a generator of Zp* is an important problem in cryptographic applications, where p is an odd prime. In this paper, we mainly consider the especial case that p is a safe prime, and give an algorithm for selecting a generator of Zp*,and find all generators of Zp* , where p is a safe prime. Our algorithm is more faster than the algorithm in [1]. Based on the proposed algorithm, one could find all generators of Zp* as well, where p is a perfect prime. 相似文献