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Journal of Tropical Meteorology 2017年第1期23卷 1-14页

作者：李冠林严卫韩丁王蕊叶晶 College of Meteorology and Oceanography PLA University of Science and TechnologyNanjing 211101 China unit No.95871 of pla HengyangHunan 421000 China

Cloud profiling radar(CPR) onboard Cloud Sat allows for deep penetration into dense clouds/precipitation. In this study, tropical cyclones(TCs) are classified into three stages as developing, mature, and decaying. The circular TC area with the radius of 500 km is divided into five regions. The vertical structure characteristics of 94 Western Pacific TCs at different stages in different regions from June 2006 to February 2014 are statistically quantified using the Cloud Sat tropical cyclone overpass product(the CSTC Product). Contoured frequency by altitude diagrams(CFADs) of radar reflectivity show an arc-like feature and exhibit opposite distributions with a boundary at 5 km. Bright bands are found at this altitude, indicating melting layers. Deep convective(DC) clouds have the largest occurrence probability in the inner region, while Ci clouds occur more frequently in the outer region at 10-15 km. As clouds have the second largest vertical scale after DC clouds. Distributions of Ac, Cu, and Ns clouds at different stages have few *** the altitude increases, the ice effective radius and the distribution width parameter decrease while the particle number concentration increases. Moist static energy(MSE), cloud thickness(CT), liquid water path(LWP), ice water path(IWP), water vapor(WV), and rain rate(RR) all diminish along the radial direction and are significantly larger at the mature stage. The average value of MSE at the developing stage is larger than that at the decaying stage.

关键词： CPR Cloud Sat tropical cyclone vertical structure statistical analysis

An accurate detection algorithm for time backtracked projectile-induced water columns based on the improved YOLO network

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Journal of Systems Engineering and Electronics 2023年第4期34卷 981-991页

作者： LUO Yasong XU Jianghu FENG Chengxu ZHANG Kun College of Weapon Engineering Naval University of EngineeringWuhan 430033China unit 91115 of the pla Zhoushan 316000China

During a sea firing training,the intelligent detection of projectile-induced water column targets in a firing video is the prerequisite for and critical to the automatic calculation of miss distance,while the correct and precise calculation of miss distance is directly affected by the accuracy,false alarm rate and time delay of *** analyzing the characteristics of projectile-induced water columns,an accurate detection algorithm for time backtracked projectile-induced water columns based on the improved you only look once(YOLO)network is put *** capability and accuracy of detecting projectileinduced water column targets with the conventional YOLO network are improved by optimizing the anchor box through K-means clustering and embedding the squeeze and excitation(SE)attention *** detection area is limited by adopting a sea-sky line detection algorithm based on gray level co-occurrence matrix(GLCM),so as to effectively eliminate such disturbances as ocean waves and ship wakes,and lower the false alarm rate of projectile-induced water column *** improved algorithm increases the mAP50 of water column detection by 30.3%.On the basis of correct detection,a time backtracking algorithm is designed with mean shift to track images containing projectile-induced water column in reverse time *** accurately detects a projectile-induced water column at the time of its initial appearance as well as its pixel position in images,and considerably reduces detection delay,so as to provide the support for the automatic,accurate,and real-time calculation of miss distance.

关键词： object recognition projectile-induced water column you only look once(YOLO) K-means squeeze and excitation(SE) mean shift

Finite sensor selection algorithm in distributed MIMO radar for joint target tracking and detection

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Journal of Systems Engineering and Electronics 2020年第2期31卷 290-302页

作者： ZHANG Haowei XIE Junwei GE Jiaang ZHANG Zhaojian LU Wenlong Air and Missile Defense College Air Force Engineering UniversityXi’an 710051China Air Force Early Warning Academy of the pla Wuhan 410039China unit 95899 of the pla Beijing 100085China

Due to the requirement of anti-interception and the limitation of processing capability of the fusion center, the subarray selection is very important for the distributed multiple-input multiple-output(MIMO) radar system, especially in the hostile environment. In such conditions, an efficient subarray selection strategy is proposed for MIMO radar performing tasks of target tracking and detection. The goal of the proposed strategy is to minimize the worst-case predicted posterior Cramer-Rao lower bound(PCRLB) while maximizing the detection probability for a certain region. It is shown that the subarray selection problem is NP-hard, and a modified particle swarm optimization(MPSO) algorithm is developed as the solution strategy. A large number of simulations verify that the MPSO can provide close performance to the exhaustive search(ES) algorithm. Furthermore, the MPSO has the advantages of simpler structure and lower computational complexity than the multi-start local search algorithm.

关键词： distributed multiple-input multiple-output(MIMO)radar subarray selection target tracking target detection particle swarm optimization(PSO)

BER Performance of Soft Decision Modulations Based on PCSS System

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Journal of Harbin Institute of Technology(New Series) 2013年第2期20卷 22-26页

作者： Ming-Duo Liu Li-Li Guo Hong-Lei Li College of Information and Communication Engineering Harbin Engineering University The 61769 unit of pla

Recently,soft decision modulations become the highlight of parallel combinatory spread spectrum ( PCSS) system. Existing soft decision BPSK and APK modulations are given and compared in the thesis. In order to apply soft decision QPSK modulation based on PCSS system,the correlation of superposition PN sequences is discussed. A weighted summation algorithm is adopted in QPSK demodulation to recover the whole orthogonal correlation of the superposition sequences; meanwhile the bit error rate of weighting soft decision QPSK modulation is simulated. The simulation results show that the bit error rate performance of proposed soft decision QPSK modulation based on PCSS system is better than that of hard decision modulation. The method proposed can be widely adopted in engineering application.

关键词： parallel combinatory spread spectrum system soft decision modulations correlation of superposition PN sequences

Acoustic multipath structure in direct zone of deep water and bearing estimation of tow ship noise of towed line array

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Chinese Physics B 2022年第5期31卷 429-437页

作者： Zhi-Bin Han Zhao-Hui Peng Jun Song Lei Meng Xiu-Ting Yang Bing Su unit 92578 of pla China State Key Laboratory of Acoustics Institute of AcousticsChinese Academy of SciencesBeijing 100190China

In the towed line array sonar system,the tow ship noise is the main factor that affects the sonar *** noise cancelling methods assume that the noise is towards the endfire direction of the *** acoustic experiment employing a towed line array is conducted in the western Pacific Ocean,and a strange bearing-splitting phenomenon of the tow ship noise is observed in the *** tow ship noise is split into multiple noise signals whose bearings are distributed between 10°and 90°deviating from the endfire *** multiple interferences increase the difficulty in recognizing the target for the sonar operator and noise ***,making the mechanism clear and putting forward the tow ship noise splitting bearing estimation method are *** this paper,the acoustic multi-path structure of the tow ship in deep water is *** it is pointed out that the bearing-splitting phenomenon is caused by the main lobe of direct rays and bottom-reflected rays,as well as several side lobes of direct ***,the indistinguishability between the elevation angle and the bearing angle due to the axial symmetry of a strict horizontal line array causes the bearing to deviate from the endfire *** on the theory above,a method of estimating bearing of the tow ship noise in deep water is *** theoretical analysis results accord with the experimental results,which helps to identify the target and provide correct initial bearing guidance for noise cancelation methods.

关键词： deep water direct zone towed line array the tow ship noise

Retrieval study of lake water depth by using multi-spectral remote sensing in Bangong Co Lake

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Research in Cold and Arid Regions 2014年第3期6卷 266-272页

作者： Pu Zheng ZhengDong Deng Xin Ye College of Defense Engineering PLA University of Science & Technology pla 96528 unit

This paper reviewed studies on remote sensing of water depth retrieval. Four water depth retrieval models （single-band, dou- ble-ratio-band, multi-band, and BP network models） were evaluated using TM image and water data from Bangong Co Lake, which is located in China＇s Tibet Autonomous Region and Indian Kashmir. Tested by independent data, comparison of these four models demonstrates that BP network model performed better than the multi-band model, with the single-band model performing the worst. To sum up, this study demonstrates that first, BP network model performed better than the traditional model; second, precise atmospheric correction and radiation study, affected by different water level sand sediment, could improve the precision of water depth retrieval.

关键词： remote sensing water depth multi-speclral retrieval Back Propagation network

Weapons system portfolio selection based on the contribution rate evaluation of system of systems

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Journal of Systems Engineering and Electronics 2019年第5期30卷 905-919页

作者： DOU Yajie ZHOU Zhexuan ZHAO Danling WEI Yong College of Systems Engineering National University of Defense TechnologyChangsha 410073China unit 31008 of the pla Beijing 100091China

The weapons system portfolio selection problem arises at the equipment demonstration stage and deals with the military application ***,the contribution rate of the system is one of the important indicators to evaluate the role of a system,which can facilitate the weapons system portfolio ***,combining the system contribution rate with system portfolio selection is the focus of this *** also focuses on calculating the contribution rates of multiple equipment systems with various types of *** contribution rate is measured by establishing a hierarchical multi-criteria value model from three *** on the value model,the feasible portfolios are developed under certain cost constraints and the optimal weapons system portfolios are obtained by using the classification optimization selection ***,an illustrative example is presented to verify the feasibility of the proposed model.

关键词： weapon system system of systems (SoS) portfolioselection contribution rate evaluation decision analysis

A highly reliable embedding algorithm for airborne tactical network virtualization

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Journal of Systems Engineering and Electronics 2021年第6期32卷 1364-1374页

作者： MIAO Jingcheng LYU Na CHEN Kefan CHEN Zhuo GAO Weiting College of Information and Navigation Air Force Engineering UniversityXi’an 710077China unit 94860 of the pla Nanjing 210000China

The evolution of airborne tactical networks(ATNs)is impeded by the network ossification *** a solution,network virtualization(NV)can provide a flexible and scalable architecture where virtual network embedding(VNE)is a key ***,existing VNE algorithms cannot be optimally adopted in the virtualization of ATN due to the complex interference in aircombat *** this context,a highly reliable VNE algorithm based on the transmission rate for ATN virtualization(TR-ATVNE)is proposed to adapt well to the specific electromagnetic environment of *** algorithm coordinates node and link *** the node mapping,transmission-rate resource is firstly defined to effectively evaluate the ranking value of substrate nodes under the interference of both environmental noises and enemy ***,a feasible splitting rule is proposed for path splitting in the link mapping,considering the interference between wireless *** results reveal that our algorithm is able to improve the acceptance ratio of virtual network requests while maintaining a high revenue-to-cost ratio under the complex electromagnetic interference.

关键词： airborne tactical network(ATN) network virtualization(NV) resource allocation virtual network embedding(VNE) transmission rate

Repair cell first,then regenerate the tissues and organs

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Military Medical Research 2021年第4期8卷 579-580页

作者： Xiao-Bing Fu Wound Healing unit Medical Innovation Department and the Fourth Medical CenterChinese PLA General Hospital and PLA Medical CollegeBeijing 100853China

Wound healing,tissue repair and regenerative medicine are in great demand,and great achievements in these fields have been *** traditional strategy of tissue repair and regeneration has focused on the level of tissues and organs directly;however,the basic process of repair at the cell level is often *** the cell is the basic unit of organism structure and function;cell damage is caused first by ischemia or ischemia-reperfusion after severe trauma and ***,damage to tissues and organs occurs with massive cell damage,apoptosis and even cell ***,how to achieve the aim of perfect repair and regeneration?The basic process of tissue or organ repair and regeneration should involve repair of cells first,then tissues and *** this manuscript,it is my consideration about how to repair the cell first,then regenerate the tissues and organs.

关键词： Cell repair Tissue repair Regenerative medicine Tissue engineering

Application and Experiment on the Least-action Principle of Explosive Welding of Stainless Steel/Steel

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Journal of Iron and Steel Research International 2014年第6期21卷 625-629页

作者： Chang-gen SHI Yu WANG Si-jing LI Jun YOU pla University of Science and Technology 78138 Troops of pla

In nature, many physical phenomena follow the least-action principle, which is also abided by the course of explosive welding of stainless steel/steel. The optimal welding interface can be obtained with the least explosive charge by theoretical analysis and interface test. The bonding energy can be acknowledged as the ＂action＂ in explosive welding. To minimize the bonding energy, these rules must be followed such as the lower limit of explosive charge, the upper limit of span and the explosive of critical explosion velocity. The principle of least-action is achieved in the course of explosive welding, and the interface will be optimum.

关键词： explosive welding least-action principle lower limit rule bonding interface