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Parameterized time-frequency analysis to separate multi-radar signals

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Journal of Systems Engineering and Electronics 2017年第3期28卷 493-502页

作者： Wenlong Lu Junwei Xie Heming Wang chuan sheng Air and Missile Defense College Air Force Engineering UniversityXi’an 710051China

Multi-radar signal separation is a critical process in modern reconnaissance systems. However, the complicated battlefield is typically confronted with increasing electronic equipment and complex radar waveforms. The intercepted signal is difficult to separate with conventional parameters because of severe overlapping in both time and frequency domains. On the contrary, time-frequency analysis maps the 1D signal into a 2D time-frequency plane, which provides a better insight into the signal than traditional methods. Particularly, the parameterized time-frequency analysis (PTFA) shows great potential in processing such non stationary signals. Five procedures for the PTFA are proposed to separate the overlapped multi-radar signal, including initiation, instantaneous frequency estimation with PTFA, signal demodulation, signal separation with adaptive filter and signal recovery. The proposed method is verified with both simulated and real signals, which shows good performance in the application on multi-radar signal separation.

关键词： intercepted multi-radar signal parameterized time-frequency analysis demodulation adaptive filtering

Method to reconnoiter pulse amplitude train for phased array radar based on Hausdorff distance

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Journal of Systems Engineering and Electronics 2017年第6期28卷 1089-1097页

作者： chuan sheng Yongshun Zhang Wenlong Lu Junwei Xie Air and Missile Defense College Air Force Engineering University Xi’an 710051 China

This paper presents a method to estimate beam pointing of phased array radar by the pulse amplitude train, which is significant in radar electronic reconnaissance and electronic support measure. Firstly, the antenna patterns modeling of the phased array system is exploited to build the radar sweeping model and the signal propagation model. Secondly, the relationship between the variation of the radiated power and the antenna beam pointing angles in the given airspace is analyzed. Based on the above two points, the sample with obvious amplitude characteristics of the pulse amplitude train can be screened out after detecting the train peaks. Finally, the sample is matched to the subsequent pulse amplitude train based on the Hausdorff distance. The proposed methods have less prior knowledge and higher efficiency and are easier to process. By cross correlating the sample of the pulse amplitude train with the sample data of the antenna follow-up radiation, the probability of detection of the beam pointing direction becomes larger in case that the subsequent antenna beam returns to the specific position.

关键词： beam pointing estimation antenna pattern pulse am plitude train Hausdorff distance

Pulse interleaving scheduling algorithm for digital array radar

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Journal of Systems Engineering and Electronics 2018年第1期29卷 67-73页

作者： ZHANG Haowei XIE Junwei ZHANG Zhaojian ZONG Binfeng sheng chuan Air and Missile Defense College Air Force Engineering UniversityXi’an 710051China Unit 94710 of the PLA Wuxi 214000China

An online pulse interleaving scheduling algorithm is proposed for a solution to the task scheduling problem in the digital array radar(DAR). The full DAR task structure is explicitly considered in a way that the waiting duration is able to be utilized to transmit or receive subtasks, namely the pulse interleaving,as well as the receiving durations of different tasks are able to be overlapped. The algorithm decomposes the pulse interleaving scheduling analysis into the time constraint check and the energy constraint check, and schedules online all kinds of tasks that are able to be interleaved. Thereby the waiting duration and the receiving duration in the DAR task are both fully utilized. The simulation results verify the performance improvement and the high efficiency of the proposed algorithm compared with the existing ones.

关键词： digital array radar(DAR) task scheduling pulse interleaving

Hierarchical Human Action Recognition with Self-Selection Classifiers via Skeleton Data

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Communications in Theoretical Physics 2018年第11期69卷 633-640页

作者： Ben-Yue Su Huang Wu Min sheng chuan-sheng Shen School of Computer and Information Anqing Normal UniversityAnqing 246133China The Key Laboratory of Intelligent Perception and Computing of Anhui Province Anqing 246133China School of Mathematics and Computational Science Anqing Normal UniversityAnqing 246133China

Human action recognition has become one of the most active research topics in human-computer interaction and artificial intelligence, and has attracted much attention. Here, we employ a low-cost optical sensor Kinect to capture the action information of the human skeleton. We then propose a two-level hierarchical human action recognition model with self-selection classifiers via skeleton data. Especially different optimal classifiers are selected by probability voting mechanism and 10 times 10-fold cross validation at different coarse grained levels. Extensive simulations on a well-known open dataset and results demonstrate that our proposed method is efficient in human action recognition, achieving 94.19%the average recognition rate and 95.61% the best rate.

关键词： human action recognition hierarchical architecture model self-selection classifiers optimal classification unit

Optical Bistability in Ag/Dielectric Multilayers

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Chinese Physics Letters 2012年第5期29卷 100-103页

作者： LI Heng sheng chuan-Xiang CHEN Qian School of Electronic Engineering and Optoelectronics Technology Nanjing University of Science and TechnologyNanjing 210094

We numerically study the optical bistability (OBIS) in periodic multilayers of Ag/SiO_(2).The calculated dependence of the output on the input intensity shows two possible OBIS states at the test *** is due to the field localization effects in silver layers with nonlinear refractive index modifying resonant tunneling of electromagnetic waves;the other,with about a three times lower threshold input intensity,is attributed to the intensity dependence change of the Ag/SiO_(2) composite's effective dielectric constant from metallic-like (negative) to dielectric-like (positive).With appropriate design engineering the Ag/SiO2 multilayers could find broad applications in all-optical information processes.

关键词： composite intensity dielectric

Changes in glutathione redox cycle during diapause determination and termination in the bivoltine silkworm, Bombyx moil

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Insect Science 2014年第1期21卷 39-46页

作者： Lin-chuan Zhao Yi-sheng Hou Yang-Hu Sima College of Biological and Basic Medicine Sciences Soochow University Suzhou Jiangsu Province China

To explore whether glutathione regulates diapause determination and termina tion in the bivoltine silkworm Bombyx mori, we monitored the changes in glutathione redox cycle in the ovary of both diapanse and nondiapauseegg producers, as well as those in dia pause eggs incubated at different temperatures. The activity ofthioredoxin reductase （TrxR） was detected in ovaries but not in eggs, while neither ovaries nor eggs showed activity of glutathione peroxidase. A lower reduced glutathione/oxidized glutathione （GSH/GSSG） ratio was observed in the ovary of diapauseegg producers, due to weaker reduction of oxidized glutathione （GSSG） to the reduced glutathione （GSH） catalyzed by glutathione reductase （GR） and TrxR. This indicates an oxidative shift in the glutathione redox cy cle during diapause determination. Compared with the 25℃treated diapause eggs, the 5℃treated diapause eggs showed lower GSH/GSSG ratio, a result of stronger oxidation of GSH catalyzed by thioredoxin peroxidase and weaker reduction of GSSG catalyzed by GR. Our study demonstrated the important regulatory role of glutathione in diapause determination and termination of the bivoltine silkworm.

关键词： Bombyx mori determination diapause glutathione redox cycle termination

Synthesis of CdTe/SiO_2 Composites and Their Fluorescence Properties

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Chemical Research in Chinese Universities 2011年第4期27卷 540-542页

作者： WANG Mei-ping LIN Jin-hui SHAN chuan-sheng College of Materials and Chemistry ＆ Chemical Engineering Chengdu University of Technology Chengdu 610059 P. R. China

Thioglycolic acid（TGA）-stabilized CdTe nanocrystals（NCs） were prepared with sodium tellurite as tellurium source,which avoids the cumbersome processes associated with H2Te or NaHTe *** CdTe/SiO2 composites were synthesized by a sol-gel method without the exchange of surface *** phase structure of CdTe NCs was investigated by X-ray *** comparison,some characterizations were done for both the CdTe NCs and the *** NCs and CdTe/SiO2 composites were characterized with TEM,digital camera and fluorescence *** stability of CdTe NCs and the composites were investigated in phosphate-buffered saline（PBS） buffer and the fluorescent properties of the composites were discussed in detail.

关键词： CdTe nanocrystal Sodium tellurite CdTe/SiO2

LiFePO_4 doped with magnesium prepared by hydrothermal reaction in glucose solution

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Chinese Chemical Letters 2008年第3期19卷 345-349页

作者： Xiu Qin Ou Guang chuan Liang Jin sheng Liang sheng Zhao Xu Xia Zhao Institute of Power Source ＆ Ecomaterials Science Box 1055 Hebei University of Technology Tianjin 300130 China

Lithium iron phosphate （LiFePO4） doped with magnesium was hydrothermally synthesized from commercial LiOH, FeSO4, H3PO4 and MgSO4 with glucose as carbon precursor in aqueous solution. The samples were characterized by X-ray powder diffraction, scanning electron microscopy and constant charge-discharge cycling. The results show that the synthesized powders have been in situ coated with carbon precursor produced from caramel reaction of glucose. At ambient temperature （28±2℃）, the electrochemical performances of LiFePO4 prepared exhibit the high discharge capacity of 135 mAh g^-1 at 5C and good capacity retention of 98% over 90 cycles. The excellent electrochemical performances should be correlated with the intimate contact between carbon and LiFePO4 primary and secondary particles, resulting from the in situ formation of carbon precursor/carbon, leading to the increase in conductivity of LiFePO4.

关键词： Lithium iron phosphate Mg doping Hydrothermal reaction Glucose Carbon coated

Pager Explosion: Cybersecurity Insights and Afterthoughts

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IEEE/CAA Journal of Automatica Sinica 2024年第12期11卷 2359-2362页

作者： chuan sheng Wanlun Ma Qing-Long Han Wei Zhou Xiaogang Zhu sheng Wen Yang Xiang Fei-Yue Wang Swinburne University of Technology IEEE the School of Computer and Mathematical Sciences the University of Adelaide Adelaide the State Key Laboratory for Management and Control of Complex Systems Chinese Academy of Sciences the Department of Engineering Science Faculty of Innovation Engineering Macau University of Science and Technology

PAGER EXPLOSION:THE EVENT THE 2024 Lebanon pager explosions represent one of the most unexpected and devastating technological incidents in recent *** September 17 and 18,2024,thousands of pagers and walkie-talkies exploded simultaneously across Lebanon and parts of Syria,resulting in 42 deaths and more than 3500 *** handheld communication devices,previously regarded as secure and low-profile,were rigged with concealed explosives and remotely triggered by attackers.

关键词： Explosions