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Equalization Reconstruction Algorithm Based on Reference Signal Frequency Domain Block Joint for DTMB-Based Passive Radar
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作者 Shuai Ma Zeqi Yang +2 位作者 Hua Zhang yiheng liu Xiaode Lyu 《Journal of Beijing Institute of Technology》 EI CAS 2024年第1期41-53,共13页
Channel equalization plays a pivotal role within the reconstruction phase of passive radar reference signals.In the context of reconstructing digital terrestrial multimedia broadcasting(DTMB)signals for low-slow-small... Channel equalization plays a pivotal role within the reconstruction phase of passive radar reference signals.In the context of reconstructing digital terrestrial multimedia broadcasting(DTMB)signals for low-slow-small(LSS)target detection,a novel frequency domain block joint equalization algorithm is presented in this article.From the DTMB signal frame structure and channel multipath transmission characteristics,this article adopts a unconventional approach where the delay and frame structure of each DTMB signal frame are reconfigured to create a circular convolution block,facilitating concurrent fast Fourier transform(FFT)calculations.Following equalization,an inverse fast Fourier transform(IFFT)-based joint output and subsequent data reordering are executed to finalize the equalization process for the DTMB signal.Simulation and measured data confirm that this algorithm outperforms conventional techniques by reducing signal errors rate and enhancing real-time processing.In passive radar LSS detection,it effectively suppresses multipath and noise through frequency domain equalization,reducing false alarms and improving the capabilities of weak target detection. 展开更多
关键词 passive radar frequency domain equalization reference signal reconstruction digital terrestrial multimedia broadcasting(DTMB)
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An Overview of Smart City in China 被引量:4
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作者 Minjie Guo yiheng liu +2 位作者 Haibin Yu Binyu Hu Ziqin Sang 《China Communications》 SCIE CSCD 2016年第5期203-211,共9页
The year of 2013 is considered the first year of smart city in China. With the development of informationization and urbanization in China, city diseases(traffic jam, medical problem and unbalanced education) are more... The year of 2013 is considered the first year of smart city in China. With the development of informationization and urbanization in China, city diseases(traffic jam, medical problem and unbalanced education) are more and more apparent. Smart city is the key to solving these diseases. This paper presents the overall smart city development in China in term of market scale and development stages, the technology standards, and industry layout. The paper claims that the issues and challenges facing smart city development in China and proposes to make polices to support smart city development. 展开更多
关键词 smart city big data city diseases city clusters smart application
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The Prediction of Population of the Yangtze Finless Porpoise
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作者 yiheng liu 《Agricultural Science & Technology》 CAS 2015年第7期1472-1476,共5页
[Objective] The aim was to study the current living situation of Yangtze finless porpoise, and explore the prediction of the number of Yangtze finless porpoise in next few years. [Method] Modified Leslie Model and Sil... [Objective] The aim was to study the current living situation of Yangtze finless porpoise, and explore the prediction of the number of Yangtze finless porpoise in next few years. [Method] Modified Leslie Model and Siler's Model was applied to estimate the number of Yangtze finless porpoise. [Result] Using the model,Yangtze finless porpoise will extinct in nearly 20 years. [Conclusion] The study provides a cautionary warning of the conservation of the freshwater cetacean species. 展开更多
关键词 Leslie Model Siler's Model Mortality rate Quantify human activity
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Treatment of femur supracondylar fracture with retrograde interlocking intramedullary nails in elderly patients
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作者 yiheng liu Haiying Zhang +1 位作者 Hongmin Zang Junchang Cheng 《Journal of Nanjing Medical University》 2006年第3期160-161,共2页
Objective: To report 32 cases of femur supracondylar fracture treated with retrograde interlocking intramedullary nails in elderly patients. Methods: According to the AO classification, all of 32 cases were classifi... Objective: To report 32 cases of femur supracondylar fracture treated with retrograde interlocking intramedullary nails in elderly patients. Methods: According to the AO classification, all of 32 cases were classified as extra-articular type A. 32 cases were treated with interlocking intramedullary nail by closed insertion from intercondylar fossa of the knee. All cases accepted CPM exercise as early as possible after operation. Results: Following up 5 to 15 months, all fractures united within an average duration of 5.3 months (4-7 months). According to the Shelbourne scale, the excellent rate of the knee function was 86.3%. Conclusion: Retrograde interlocking intramedullary nail is useful alternative implant for the treatment of osteoporotic supracondylar fracture of femur, particularly of the type A fracture in the elderly population. Its merits include stable fixation, high rate of fracture union and few complications. 展开更多
关键词 femur supracondylar fracture interlocking intramedullary nails fracture fixation
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拉曼光谱技术在深空探测中的应用评述 被引量:2
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作者 刘平 齐晓彬 +6 位作者 刘毅恒 王晓玉 刘长卿 辛艳青 肖阿阳 张江 凌宗成 《科学通报》 EI CAS CSCD 北大核心 2023年第27期3634-3653,共20页
拉曼光谱是激光激发物质产生光子非弹性散射形成的分子振动光谱.作为矿物和有机物识别的“指纹”光谱,拉曼光谱已被广泛应用于地球和地外样品研究中,以获得矿物种类、矿物化学、空间分布、岩矿成因等关键信息.在深空探测任务中,拉曼光... 拉曼光谱是激光激发物质产生光子非弹性散射形成的分子振动光谱.作为矿物和有机物识别的“指纹”光谱,拉曼光谱已被广泛应用于地球和地外样品研究中,以获得矿物种类、矿物化学、空间分布、岩矿成因等关键信息.在深空探测任务中,拉曼光谱通过采用主动激光激发获取光谱,在光谱信号获取方面具有独特的优势并可有效突破行星光照条件等环境的制约,因而被推荐用于月球、火星、小行星、金星、冰卫星等重要探测任务.我国嫦娥7号任务也将搭载拉曼光谱仪在月球南极区域开展就位物质成分探测.本文从拉曼光谱技术的物理原理和技术特点出发,阐述了拉曼光谱技术在月球和火星样品中的研究进展,归纳总结了主要组成矿物的拉曼光谱特征;梳理了拉曼光谱技术在深空探测领域的发展现状,简介了目前国际上主要拉曼光谱仪载荷设计情况,并分析了深空拉曼光谱探测中存在的难点约束;最后,对拉曼光谱技术在深空探测应用方面未来的发展趋势进行了展望,以期为未来相关载荷研发和应用提供有益参考. 展开更多
关键词 物质成分 月球 火星 地外样品 拉曼光谱 载荷
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