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High performance receiving and processing technology in satellite beam hopping communication

Journal of Systems Engineering and Electronics 2024年第4期35卷 815-828页

作者： ZHAI Shenghua hui tengfei GONG Xianfeng ZHANG Zehui GAO Xiaozheng YANG Kai School of Communication Engineering Xi’Dian UniversityXian 710126China CAST(China Academy of Space Technology)-Xi’an Institute of Space Radio Technology Xi’an 710010China School of Cyberspace Science and Technology Beijing Institute of TechnologyBeijing 100081China School of Information and Electronics Beijing Institute of TechnologyBeijing 100081China

Beam-hopping technology has become one of the major research hotspots for satellite communication in order to enhance their communication capacity and ***,beam hopping causes the traditional continuous time-division multiplexing signal in the forward downlink to become a burst signal,satellite terminal receivers need to solve multiple key issues such as burst signal rapid synchronization and high-per-formance ***,this paper analyzes the key issues of burst communication for traffic signals in beam hopping sys-tems,and then compares and studies typical carrier synchro-nization algorithms for burst ***,combining the requirements of beam-hopping communication systems for effi-cient burst and low signal-to-noise ratio reception of downlink signals in forward links,a decoding assisted bidirectional vari-able parameter iterative carrier synchronization technique is pro-posed,which introduces the idea of iterative processing into car-rier *** at the technical characteristics of communication signal carrier synchronization,a new technical approach of bidirectional variable parameter iteration is adopted,breaking through the traditional understanding that loop struc-tures cannot adapt to low signal-to-noise ratio burst ***,combining the DVB-S2X standard physical layer frame format used in high throughput satellite communication systems,the research and performance simulation are *** results show that the new technology proposed in this paper can significantly shorten the carrier synchronization time of burst signals,achieve fast synchronization of low signal-to-noise ratio burst signals,and have the unique advantage of flexible and adjustable parameters.

关键词： beam-hopping high throughput satellite high per-formance reception processing

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Experiencing urban forests for mitigation of negative emotions of people exposed to seasonal PM_(2.5)in Northeast China

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林业研究:英文版 2023年第5期34卷 1245-1261页

作者： Jie Zhang Zhi Yang Yuxiang Sun Zhihui Xu tengfei hui Peng Guo Forestry College Beihua UniversityJilin 132103People’s Republic of China Department of Human Resources Management School of Business and ManagementJilin UniversityChangchun 130021People’s Republic of China Environment and Resources College Dalian Minzu UniversityDalian 116600People’s Republic of China

Experiencing urban green and blue spaces(GBSs)can be a nature-based solution to improve mental well-being and cope with negative moods for people exposed to PM2.5 *** this study,a total of 1257 photos were collected to recognize their posted emotions of Sina Weibo users from 38 parks in 22 cities in Northeast China in 2021,when atmospheric PM_(2.5)and landscape metrics were evaluated for GBSs of each *** and winter had heavy atmospheric PM_(2.5)pollutions in resource-dependent cities of *** positive emotions(happy minus sad scores)decreased in larger green *** perception of blue space countered the presentation of sadness only for a limited period over four *** elevation decreased the level of happiness presented in ***,this study confirms that visiting large urban green spaces at low elevations can benefit the perception of positive sentiments for people exposed to PM_(2.5)in *** planning urban forests in Northeast China,more green spaces should be constructed in cities in southern Jilin province to alleviate air PM_(2.5)pollution and gain better well-being of local people.

关键词： Urban forest park Mental health and well-being Green and blue infrastructures Sustainable urban forests

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吉林省森林公园自然声喜好度调查

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北华大学学报（自然科学版） 2024年第3期25卷 397-404页

作者：杨智刘梦竹回腾飞左晶张洁北华大学林学院吉林吉林132013

自然声是森林公园资源的重要组成部分,直接影响森林公园景观规划及生物多样性栖息地建设与经营。采用问卷调查法调查吉林省7个森林公园44种自然声喜好度。结果表明:被调查者普遍偏好自然声,其中5种主要类型自然声受欢迎程度依次为流水声... 详细信息

自然声是森林公园资源的重要组成部分,直接影响森林公园景观规划及生物多样性栖息地建设与经营。采用问卷调查法调查吉林省7个森林公园44种自然声喜好度。结果表明:被调查者普遍偏好自然声,其中5种主要类型自然声受欢迎程度依次为流水声>雨声>鸟鸣声>风声>昆虫声;自然声时间性表现为夏季好于冬季、日间好于夜间;人口学特征中,性别、年龄段、教育背景等都影响人们对自然声的喜好。研究结果有助于指导森林公园的声景改造和管理,从而提升公众的游览体验。

关键词：吉林省森林公园自然声问卷调查喜好度

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基于太阳周期特性的低轨卫星通信信道建模

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电子设计工程 2024年第3期32卷 65-68,73页

作者：吴桐张登越刘明洋龚险峰李雄飞惠腾飞中国空间技术研究院西安分院陕西西安710000

针对低轨卫星星地通信时,通信信道中复杂的地球大气状况,提出了基于太阳周期特性的低轨卫星通信信道模型。该模型利用了地球电离层电子密度、对流层粒子密度的统计学特征,统一考虑了电离层和对流层的幅度闪烁和多普勒扩展效应,引入了太... 详细信息

针对低轨卫星星地通信时,通信信道中复杂的地球大气状况,提出了基于太阳周期特性的低轨卫星通信信道模型。该模型利用了地球电离层电子密度、对流层粒子密度的统计学特征,统一考虑了电离层和对流层的幅度闪烁和多普勒扩展效应,引入了太阳周期活动因素导致的信道模型修正系数,提高了信道模型的适用范围。通过仿真分析,该模型能够反映不同太阳周期活动下,低轨卫星通信信道对通信信号的影响,为低轨卫星大规模部署后的通信测试和使用提供了理论基础。

关键词：幅度闪烁多普勒扩展低轨卫星通信信道建模

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健康视域下声景CiteSpace可视化分析

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北华大学学报（自然科学版） 2024年第3期25卷 381-396页

作者：张洁左晶回腾飞毛爱欣宋时屿祝爱昀杨智北华大学林学院吉林吉林132013

收集2000—2023年Web of ScienceTM和CNKI数据库中关于声景与健康的相关文献,利用CiteSpace软件进行可视化文献计量分析,共筛选出544篇有效论文。研究发现:该领域论文数量呈现稳定增长趋势;研究机构整体分布较为分散,尽管单个机构内部... 详细信息

收集2000—2023年Web of ScienceTM和CNKI数据库中关于声景与健康的相关文献,利用CiteSpace软件进行可视化文献计量分析,共筛选出544篇有效论文。研究发现:该领域论文数量呈现稳定增长趋势;研究机构整体分布较为分散,尽管单个机构内部合作紧密,但跨机构合作尚显不足,互动交流有待加强;研究热点已从初期的环境噪声逐渐转向声景感知,探讨声景与生态效益的关联;声景与健康领域的热门话题表现为多学科多理论相互融合、研究载体日趋细化、研究方法多样化以及新兴技术不断引入。鉴于目前该领域存在的跨学科合作和数字化应用不足,未来研究应更加注重跨学科合作和人工智能等新技术应用,进一步提高对精准度与实践性的重视程度。研究结果揭示了国内外声景与健康研究的总体特点、热点问题及发展趋势。

关键词：声景健康 CiteSpace 知识图谱文献计量

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Engineered exosome hybrid copper nanoscale antibiotics facilitate simultaneous self-assembly imaging and elimination of intracellular multidrug-resistant superbugs

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Chinese Chemical Letters 2024年第7期35卷 319-324页

作者： Zengchao Guo Weiwei Liu tengfei Liu Jinpeng Wang hui Jiang Xiaohui Liu Yossi Weizmann Xuemei Wang State Key Laboratory of Digital Medical Engineering School of Biological Science and Medical EngineeringSoutheast UniversityNanjing 210096China Department of Chemistry Ben-Gurion University of the NegevBeer-Sheva 8410501Israel

With the increasing emergence of bacterial infections,especially multidrug-resistant(MDR)bacteria,poses an urgent *** study demonstrated a novel multifunctional nanotheranostics platform developed by the strategic integration of both in-situ bio-assembly imaging and target bacteria *** the introduction of copper ions into bacteria,the Cu^(2+)could spontaneously bio-selfassembled into a multifunctional copper nanoclusters(NCs)which efficiently enhanced epigallocatechin gallate(EGCG)uptake into *** visualizing the bacteria,the developed theranostic nanoplatform exhibited highly efficient disinfection activities with negligible side effects as reflected by higher cell viability and insignificant hemolytic ***,the exosomal formulation of EGCG integrated with Cu^(2+)showed an increased intracellular antibacterial activity,which could eliminate most of the methicillin-resistant Staphylococcus aureus(MRSA)phagocytosed by macrophages,guide macrophages toward M2-like phenotype polarization and alleviate inflammation,without exhibiting obvious cytotoxicity on host *** regimen could be viewed as an effective strategy for the sterilization of intractable bacterial infections.

关键词： In situ self-assembled Exosome Antibacterial agents Bioimaging Intracellular infection

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New insight into targeting the DNA damage response in the treatment of glioblastoma

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Chinese Journal of Natural Medicines 2024年第10期22卷 869-886页

作者： ZHEN tengfei SUN Tianyu XIONG Baichen LIU hui WANG Lei CHEN Yao SUN Haopeng School of Pharmacy China Pharmaceutical University Department of Chemistry Tsinghua University School of Pharmacy Nanjing University of Chinese Medicine

Glioblastoma(GBM) is the most common invasive malignant tumor in human brain tumors, representing the most severe grade of gliomas. Despite existing therapeutic approaches, patient prognosis remains dismal, necessitating the exploration of novel strategies to enhance treatment efficacy and extend survival. Due to the restrictive nature of the blood-brain barrier(BBB), smallmolecule inhibitors are prioritized in the treatment of central nervous system tumors. Among these, DNA damage response(DDR) inhibitors have garnered significant attention due to their potent therapeutic potential across various malignancies. This review provides a detailed analysis of DDR pathways as therapeutic targets in GBM, summarizes recent advancements, therapeutic strategies, and ongoing clinical trials, and offers perspectives on future directions in this rapidly evolving field. The goal is to present a comprehensive outlook on the potential of DDR inhibitors in improving GBM management and outcomes.

关键词： DNA damage response Glioblastoma Small molecule inhibitors

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直升机卫星通信中高动态低信噪比突发解调

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南京航空航天大学学报 2022年第2期54卷 219-224页

作者：龚险峰刘明洋惠腾飞中国空间技术研究院西安分院西安710100 西安电子科技大学ISN国家重点实验室西安710071

采用突发通信模式的低速直升机卫星通信链路同时存在周期性的旋翼遮挡和较大的多普勒动态,且需要工作在低信噪比下,这些特点对解调提出了很大挑战,需要研究高性能、低复杂度的突发解调方法。本文基于分散导频帧结构提出一种译码辅助解... 详细信息

采用突发通信模式的低速直升机卫星通信链路同时存在周期性的旋翼遮挡和较大的多普勒动态,且需要工作在低信噪比下,这些特点对解调提出了很大挑战,需要研究高性能、低复杂度的突发解调方法。本文基于分散导频帧结构提出一种译码辅助解调方法。首先进行频偏分区预补偿,然后进行联合频率变化率估计的突发捕获,最后根据译码软输出目标函数,从多路译码输出中选择最优的一路作为最终结果。在给定的信道模型下,与无遮挡高斯白噪声(Additive white Gaussian noise,AWGN)信道下的理论性能相比,解调门限仅提高1.5 dB。与缝隙通信方式的典型性能相比,前向链路信噪比损失降低1.5 dB,返向链路信噪比损失增大0.2 dB。

关键词：卫星通信旋翼遮挡多普勒动态译码辅助解调缝隙通信

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Extracellular vesicles from human urine-derived stem cells delay aging through the transfer of PLAU and TIMP1

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Acta Pharmaceutica Sinica B 2024年第3期14卷 1166-1186页

作者： Shanshan Rao Zehui He Zun Wang Hao Yin Xiongke Hu Yijuan Tan tengfei Wan Hao Zhu Yi Luo Xin Wang Hongming Li Zhenxing Wang Xinyue Hu Chungu Hong Yiyi Wang Mingjie Luo Wei Du Yuxuan Qian Siyuan Tang hui Xie Chunyuan Chen Department of Orthopedics Movement System Injury and Repair Research CenterXiangya HospitalCentral South UniversityChangsha 410008China Hunan Key Laboratory of Angmedicine Changsha 410008China Xiangya School of Nursing Central South UniversityChangsha 410013China Department of Pediatric Orthopedics Hunan Children’s HospitalUniversity of South ChinaChangsha 410007China Department of Respiratory Medicine Xiangya HospitalCentral South UniversityChangsha 410008China School of Nursing Xinjiang Medical UniversityUrumqiXinjiang 830000China Department of Rehabilitation Xiangya HospitalCentral South UniversityChangsha 410008China National Clinical Research Center for Geriatric Disorders Xiangya HospitalCentral South UniversityChangsha 410008China

Aging increases the risks of various diseases and the vulnerability to *** senescence is a hallmark of aging that contributes greatly to aging and aging-related *** study demonstrates that extracellular vesicles from human urine-derived stem cells(USC-EVs)efficiently inhibit cellular senescence in vitro and in *** intravenous injection of USC-EVs improves cognitive function,increases physical fitness and bone quality,and alleviates aging-related structural changes in different organs of senescence-accelerated mice and natural aging *** anti-aging effects of USC-EVs are not obviously affected by the USC donors’ages,genders,or health *** analysis reveals that USC-EVs are enriched with plasminogen activator urokinase(PLAU)and tissue inhibitor of metalloproteinases 1(TIMP1).These two proteins contribute importantly to the anti-senescent effects of USC-EVs associated with the inhibition of matrix metalloproteinases,cyclin-dependent kinase inhibitor 2A(P16INK4a),and cyclin-dependent kinase inhibitor 1A(P21cip1).These findings suggest a great potential of autologous USC-EVs as a promising anti-aging agent by transferring PLAU and TIMP1 proteins.

关键词： Extracellular vesicles Urine-derived stem cells Cellular senescence Anti-aging PLAU TIMP1 Senescence-accelerated mice Natural aging mice

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火星探测UHF频段原位通信关键技术研究

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中国空间科学技术 2023年第2期43卷 103-116页

作者：翟盛华田嘉董超李雄飞惠腾飞中国空间技术研究院西安分院西安710100

火星是人类探索太阳系的下一个里程碑,由于地球和火星之间的距离非常遥远(最远距离约4亿千米,光行时约22 min),为了最大限度地完成火星车和地球之间的高效通信,火星车和火星环绕器之间的器间原位中继通信技术就显得尤为重要。针对大椭... 详细信息

火星是人类探索太阳系的下一个里程碑,由于地球和火星之间的距离非常遥远(最远距离约4亿千米,光行时约22 min),为了最大限度地完成火星车和地球之间的高效通信,火星车和火星环绕器之间的器间原位中继通信技术就显得尤为重要。针对大椭圆轨道下器间通信信噪比低、信号参数变化快、全自主要求高及质量功耗约束极为严苛等难点,提出了一种UHF频段器间原位通信技术,主要包括超高灵敏度高动态自适应信号解调、高精度多普勒测量、基于CCSDS Proximity-1的协议一体化集成融合和面向火星复杂环境的高集成度高收发隔离产品工程化设计,实现了捕获灵敏度优于-141 dBm、解调灵敏度(1 kbit/s)优于-134 dBm、频率动态范围优于±26 kHz、多普勒测量精度优于10 mHz、收发隔离大于180 dB、弧段内全自主高可靠高吞吐率通信及基于架构统型的系统/单机极限优化,相关指标优于美国系列火星探测器中的“Electra”。经祝融号火星车和天问一号火星环绕器、ESA“Mars Express”火星轨道器在轨实际测试,测试数据符合预期,为中国首次火星探测的圆满成功做出了重要贡献。

关键词：火星探测 UHF频段原位通信技术 CCSDS临近空间链路协议产品工程化设计

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