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991.
一种PD雷达解距离模糊的新算法 总被引:4,自引:0,他引:4
针对PD雷达的解距离模糊问题,文中分析指出一维集算法解模糊计算量大,有时难以适应实时测距的要求.基于此点,在一维集算法基础之上提出了一种新的解模糊方法,通过理论分析证明了这种方法的计算量明显小于一维集算法,而且具有良好的误差纠错能力,并将这种新算法同余差查表法的各项性能进行了对比,体现了其同样具有较好的实时性能和较强的解模糊能力.最后给出利用这种算法解单目标距离模糊的仿真结果,表明了这种方法的有效性. 相似文献
992.
993.
针对雷达部署及机动备份对雷达装备生存能力评估的需求,综合运用了参数效能法、专家评估法、量化标尺评价法、阶段概率法、模糊评价法和概率矩阵法等效能评估方法,提出了一种对空情报雷达装备生存能力评估模型,并用实例验证了该模型的科学性与合理性. 相似文献
994.
姜浩 《信息安全与通信保密》2006,(10):49-50
论文详细描述并分析了从RC5到RC6的演化设计过程,在详细研究了RC6性能的同时,指出了应该如何从一个旧的密码设计出好的新密码。最后对RC6和Rijndael作了一些比较,指出各自在性能上的优缺点。 相似文献
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997.
Wenyan Ma Lian-Wei Luo Peihua Dong Peiyun Zheng Xiuhua Huang Chong Zhang Jia-Xing Jiang Yong Cao 《Advanced functional materials》2021,31(45):2105027
Recent studies have demonstrated that dihydrophenazine (Pz) with high redox-reversibility and high theoretical capacity is an attractive building block to construct p-type polymer cathodes for dual-ion batteries. However, most reported Pz-based polymer cathodes to date still suffer from low redox activity, slow kinetics, and short cycling life. Herein, a donor–acceptor (D–A) Pz-based conjugated microporous polymer (TzPz) cathode is constructed by integrating the electron-donating Pz unit and the electron-withdrawing 2,4,6-triphenyl-1,3,5-triazine (Tz) unit into a polymer chain. The D–A type structure enhances the polymer conjugation degree and decreases the band gap of TzPz, facilitating electron transportation along the polymer skeletons. Therefore the TzPz cathode for dual-ion battery shows a high reversible capacity of 192 mAh g−1 at 0.2 A g−1 with excellent rate performance (108 mAh g−1 at 30 A g−1), which is much higher than that of its counterpart polymer BzPz produced from 1,3,5-triphenylbenzene (Bz) and Pz (148 and 44 mAh g−1 at 0.2 and 10 A g−1, respectively). More importantly, the TzPz cathode also shows a long and stable cyclability of more than 10 000 cycles. These results demonstrate that the D–A structural design is an efficient strategy for developing high-performance polymer cathodes for dual-ion batteries. 相似文献
998.
Junyu Chen Yuze Li Yuming Jiang Liucheng Mao Mi Lai Lixia Jiang Huihui Liu Zongxiu Nie 《Advanced functional materials》2021,31(52):2106743
Cancer remains an intractable medical problem. Rapid diagnosis and identification of cancer are critical to differentiate it from nonmalignant diseases. High-throughput biofluid metabolic analysis has potential for cancer diagnosis. Nevertheless, the present metabolite analysis method does not meet the demand for high-throughput screening of diseases. Herein, a high-throughput, cost-effective, and noninvasive urine metabolic profiling method based on TiO2/MXene-assisted laser desorption/ionization mass spectrometry (LDI-MS) is presented for the efficient screening of bladder cancer (BC) and nonmalignant urinary disease. Combined with machine learning, TiO2/MXene-assisted LDI-MS enables high diagnostic accuracy (96.8%) for the classification of patient groups (including 47 BC and 46 ureteral calculus (UC) patients) from healthy controls (113 cases). In addition, BC patients can also be identified from noncancerous UC individuals with an accuracy of 88.3% in the independent test cohort. Furthermore, metabolite variations between BC and UC individuals are investigated based on relative quantification, and related pathways are also discussed. These results suggest that this method, based on urine metabolic patterns, provides a potential tool for rapidly distinguishing urinary diseases and it may pave the way for precision medicine. 相似文献
999.
Zhuo Sun Xinjian Jiang Dongqi Zhu Guixin Zhang 《Power Electronics, IEEE Transactions on》2004,19(4):1036-1042
To improve the power quality of traction power system, a novel active power quality compensator (APQC) and a new compensating currents detection method are proposed. The APQC consists of a three-phase voltage source converter and a Scott transformer. The Scott transformer, taken as an isolation transformer, not only connects the three-phase converter to the traction power system, but also converts the traction power system to a nearly balanced three-phase power system. Therefore, a general three-phase converter could be used in APQC. Regarding the traction substation as a compensating object, the power quality of a traction substation can be improved integrally. Simulation and prototype experimental results show that the proposed APQC is able to compensate reactive power, harmonic, and negative-sequence currents in two feeders of a traction substation. 相似文献
1000.
Zhaowu Tang Chunsen Liu Senfeng Zeng Xiaohe Huang Liwei Liu Jiayi Li Yugang Jiang David Wei Zhang Peng Zhou 《半导体学报》2021,42(2):103-108
The recently reported quasi-nonvolatile memory based on semi-floating gate architecture has attracted extensive at-tention thanks to its potential to bridge the large gap between volatile and nonvolatile memory.However,the further exten-sion of the refresh time in quasi-nonvolatile memory is limited by the charge leakage through the p-n junction.Here,based on the density of states engineered van der Waals heterostructures,the leakage of electrons from the floating gate to the channel is greatly suppressed.As a result,the refresh time is effectively extended to more than 100 s,which is the longest among all pre-viously reported quasi-nonvolatile memories.This work provides a new idea to enhance the refresh time of quasi-nonvolatile memory by the density of states engineering and demonstrates great application potential for high-speed and low-power memory technology. 相似文献