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A BRIEF INTRODUCTION TO MERIDIAN PROJECT

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空间科学学报 2002年第Z1期22卷 35-38页

作者： WEI fengsi XIAO Zuo wu Jian guo Jianshan feng Xueshang Center for Space Science and Applied Research The Chinese Academy of Sciences Beijing 100080 P.R. China Department of Geophysics Peking University P.R. China Institute of Radio Propagation Ministry of Information Industry P.R.China Center for Space Science and Applied Research The Chinese Academy of Sciences Beijing 100080 P.R. China Center for Space Science and Applied Research The Chinese Academy of Sciences Beijing 100080 P.R. China

　　Early in 1994, sponsored by Chinese Academy of Sciences (CAS) and then the State Science and Technology Commission of China (SSTC, now Ministry of Sci ence and Technology), Chinese space scientists (including scientists from Taiwan) gathered together to discuss issues on the development of space physics researches in China. Following it, several special seminars were held to continue the discus sion which finally led to a proposal to CAS and SSTC for establishing a station chain along the 120°E to monitor the space environment. This proposal was care fully reviewed and thoroughly evaluated by many leading scientists in the com munity and then listed in the State Plan of Chinese Central Government in June 1997. The project then has been formally called as "Meridian Chain of Compre hensive Ground-Based Space Environment Monitors in the Eastern Hemisphere" "Meridian Project". After several years of preparations the project has been par tially initiated with the efforts devoted by institutes and universities involved.……

关键词： space environment Science and Technology

Sky location of massive black hole binaries in the foreground of Galactic white dwarf binaries

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 97-108页

作者： Pan guo Hong-Bo Jin Cong-feng Qiao Yue-Liang wu The International Centre for Theoretical Physics Asia-Pacific University of Chinese Academy of Sciences The School of Physical Sciences University of Chinese Academy of Sciences Institute for Frontiers in Astronomy and Astrophysics Beijing Normal University National Astronomical Observatories Chinese Academy of Sciences Institute of Theoretical Physics Chinese Academy of Sciences

For space-based gravitational wave （GW） detection,the main noise source for massive black hole binaries （MBHBs） is attributed to approximately 10～7double white dwarf binaries in the *** a GW source,the amplitude of the detector response,recorded by a space-based gravitational wave detector,exhibits a modulation effect with a year period when observing the source from various orbital *** the adverse conditions mentioned above,where there is a strong foreground noise and annual modulation in the signals,we employed the wavelet transform and the strong-amplitude relevant orbital position search methods,which allows the weak MBHB sources to achieve higher locating *** detail,for two MBHB sources of lower intensity,the precision of luminosity distance,represented by the ratio ?DL/DLat the 95%confidence level,is enhanced by factors of ～*** angular resolutions,denoted by??s,are enhanced by a factor of ～*** improvements increase the number of detectable GW sources,facilitate multi-messenger follow-up observations and provide constraints on the cosmological constant.

关键词： space-based gravitational wave detection gravitational waves massive black hole binaries

Perihematomal endothelin-1 level is associated with an increase in blood-brain barrier permeability in a rabbit model of intracerebral hematoma

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Chinese Medical Journal 2013年第18期126卷 3433-3438页

作者： WANG Li-kun HONG Zhen wu guo-feng LI Chang Department of Neurology Affiliated Huashan Hospital of Fudan University Shanghai 200036 China Department of Neurology Affiliated Hospital of Guiyang Medical University Guiyang Guizhou 550004 China

Background Endothelin-1 （ET-1） has deleterious effects on water homeostasis, cerebral edema, and blood-brain barrier （BBB） integrity. Highly expressed ET-1 was observed after intracerebral hemorrhage （ICH）; however, ET-1 changes and their relationship with BBB disruption within 24 hours of ICH have not been thoroughly investigated. The aim of the present study was to observe the changes in perihematomal ET-1 levels in various phases of ICH and their correlation with the BBB integrity in a rabbit model of ICH. Methods Twenty-five rabbits （3.2-4.3 kg body weight） were randomly divided into a normal control group （five rabbits） and a model group （20 rabbits）. Animals in the model group were equally divided into four subgroups （five rabbits each to be sacrificed at 6, 12, 18, and 24 hours following ICH establishment）. An ICH model was prepared in the model group by infusing autologous arterial blood into the rabbit brain. ET-1 expression in perihematomal brain tissues was determined using immunohistochemistry and color image analysis, and the permeability of the BBB was assayed using the Evan＇s Blue （EB） method. A repeated measures analysis of variance was used to make comparisons of the ET-1 and EB content across the entire time series. Results The number of perihematomal endothelial cells with ET-1 positive expressions following 6, 12, 18, and 24 hours ICH model establishment was 9.32, 13.05, 15.90, and 20.44, respectively, but as low as 6.67 in the control group. The average transmittance of ET-1-positive cell bodies at 6, 12, 18, and 24 hours after ICH was 99.10, 97.40, 85.70, and 80.80, respectively, but 100.12 in the control group. These data reveal that the expression of ET-1 was significantly increased at 6, 12, 18, and 24 hours after ICH compared with the control group, and a marked decrease in the average transmittance of ET-l-positive cell bodies was noted （P 〈0.05）. Similarly, the perihematomal EB content at 6, 12, 18, and 24 hours after ICH was 29.39±1.16,

关键词： intracerebral hemorrhage endothelin-1 blood-brain barrier Evan's blue brain edema

Observation of acoustic hybrid topological phases induced by the p-d orbital interactions

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 132-139页

作者： Xiao Xiang feng Gao Yu-Gui Peng Peng wu Zong-Lin Li Xue-feng Zhu School of Physics and Innovation Institute Huazhong University of Science and Technology

In spinless systems,growing attention has recently been attracted to synthetic gauge fields,which redefine the fundamental crystal symmetries by utilizing the projective algebraic ***,synthetic gauge fields have been commonly investigated in single orbital systems,and explorations on hybrid orbitals remain elusive in ***,we report the experimental observation of hybrid topological phases induced by hybrid synthetic gauge flux,which is formed by the interaction between p and d orbitals embedded in acoustic *** breaking the translation symmetries of Lxand/or Ly,we unambiguously demonstrate the first-order M?bius edge states and higher-order corner *** work establishes a platform for seeking exotic topological phases induced by hybrid-orbitals interactions and initializing the framework of hybrid-orbitalsrelated topological *** applications can be anticipated in scenarios such as high-quality sensing and robust wave trapping due to the stepwise energy distribution of the hybrid topological phase.

关键词： topological insulator synthetic gauge field projective symmetry corner states

双瑞利衰落下AP中继车际通信系统误符号率分析

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西安电子科技大学学报 2010年第5期37卷 947-952,970页

作者：李兆训李峰仵国锋胡捍英解放军信息工程大学河南郑州450002

基于双瑞利衰落模型,对无线接入点AP中继的车际通信系统的差错性能展开研究.在采用放大转发中继策略的前提下,分析了端到端接收信噪比的统计特性,采用基于矩生成函数的方法得到了包含多种调制方式在内的系统平均误符号率的通用表达式.... 详细信息

基于双瑞利衰落模型,对无线接入点AP中继的车际通信系统的差错性能展开研究.在采用放大转发中继策略的前提下,分析了端到端接收信噪比的统计特性,采用基于矩生成函数的方法得到了包含多种调制方式在内的系统平均误符号率的通用表达式.仿真表明,采用中继技术可以减小车际通信系统的平均误符号率;与M-PSK调制相比,系统采用差分相干M-DPSK会有2~3 dB的信噪比损失,具体数值取决于不同的信噪比和M值;相对于等功率分配方案,最佳功率分配方法可使协作车际通信系统获得2.4 dB的最大增益.

关键词：车际通信中继误符号率双瑞利衰落矩生成函数最佳功率分配

Bioinspired Passive Tactile Sensors Enabled by Reversible Polarization of Conjugated Polymers

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Nano-Micro Letters 2025年第1期17卷 361-377页

作者： feng He Sitong Chen Ruili Zhou Hanyu Diao Yangyang Han Xiaodong wu School of Mechanical Engineering Sichuan UniversityChengdu 610065People’s Republic of China School of Software Engineering Chongqing University of Posts and TelecommunicationsChongqing 400065People’s Republic of China State Key Laboratory of Polymer Materials Engineering Sichuan UniversityChengdu 610065People’s Republic of China

Tactile perception plays a vital role for the human body and is also highly desired for smart prosthesis and advanced *** to active sensing devices,passive piezoelectric and triboelectric tactile sensors consume less power,but lack the capability to resolve static ***,we address this issue by utilizing the unique polarization chemistry of conjugated polymers for the first time and propose a new type of bioinspired,passive,and bio-friendly tactile sensors for resolving both static and dynamic ***,to emulate the polarization process of natural sensory cells,conjugated polymers(including poly(3,4-ethylenedioxythiophen e):poly(styrenesulfonate),polyaniline,or polypyrrole)are controllably polarized into two opposite states to create artificial potential *** controllable and reversible polarization process of the conjugated polymers is fully in situ ***,a micro-structured ionic electrolyte is employed to imitate the natural ion channels and to encode external touch stimulations into the variation in potential difference *** with the currently existing tactile sensing devices,the developed tactile sensors feature distinct characteristics including fully organic composition,high sensitivity(up to 773 mV N^(−1)),ultralow power consumption(nW),as well as superior *** demonstrations,both single point tactile perception(surface texture perception and material property perception)and two-dimensional tactile recognitions(shape or profile perception)with high accuracy are successfully realized using self-defined machine learning *** tactile sensing concept innovation based on the polarization chemistry of conjugated polymers opens up a new path to create robotic tactile sensors and prosthetic electronic skins.

关键词： Passive tactile sensors Reversible polarization of conjugated polymers Tactile perception Machine learning algorithm Object recognition

Multiple Tin Compounds Modified Carbon Fibers to Construct Heterogeneous Interfaces for Corrosion Prevention and Electromagnetic Wave Absorption

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Nano-Micro Letters 2025年第1期17卷 507-527页

作者： Zhiqiang guo Di Lan Zirui Jia Zhenguo Gao Xuetao Shi Mukun He Hua guo Guanglei wu Pengfei Yin College of Science Sichuan Agricultural UniversityYa’an 625014People’s Republic of China School of Materials Science and Engineering Hubei University of Automotive TechnologyShiyan 442002People’s Republic of China Institute of Materials for Energy and Environment State Key Laboratory of Bio‑Fibers and Eco‑TextilesCollege of Materials Science and EngineeringQingdao UniversityQingdao 266071People’s Republic of China Shaanxi Key Laboratory of Macromolecular Science and Technology School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’anShaanxi 710072People’s Republic of China

Currently,the demand for electromagnetic wave(EMW)absorbing materials with specific functions and capable of withstanding harsh environments is becoming increasingly ***-component interface engineering is considered an effective means to achieve high-efficiency EMW ***,interface modulation engineering has not been fully discussed and has great potential in the field of EMW *** this study,multi-component tin compound fiber composites based on carbon fiber(CF)substrate were prepared by electrospinning,hydrothermal synthesis,and high-temperature thermal *** utilizing the different properties of different substances,rich heterogeneous interfaces are *** effectively promotes charge transfer and enhances interfacial polarization and conduction *** prepared SnS/SnS_(2)/SnO_(2)/CF composites with abundant heterogeneous interfaces have and exhibit excellent EMW absorption properties at a loading of 50 wt%in epoxy *** minimum reflection loss(RL)is−46.74 dB and the maximum effective absorption bandwidth is 5.28 ***,SnS/SnS_(2)/SnO_(2)/CF epoxy composite coatings exhibited long-term corrosion resistance on Q235 steel ***,this study provides an effective strategy for the design of high-efficiency EMW absorbing materials in complex and harsh environments.

关键词： Electrostatic spinning Component regulation Heterogeneous interfaces Electromagnetic wave absorption Corrosion protection

A Verifiable Trust-Based CP-ABE Access Control Scheme for Cloud-Assisted Renewable Energy Systems

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Computers, Materials & Continua 2025年第1期82卷 1211-1232页

作者： Jiyu Zhang Kehe wu Ruomeng Yan Zheng Tian Yizhen Sun Yuxi wu Yaogong guo Department of Control and Computer Engineering North China Electric Power UniversityBeijing102206China State Grid Information&Communication Company of Hunan Electric Power Corporation Changsha410118China State Grid Hunan Electric Power Corporation Chenzhou Power Supply Branch Chenzhou423000China

Renewable Energy Systems(RES)provide a sustainable solution to climate warming and environmental pollution by enhancing stability and reliability through status acquisition and analysis on cloud platforms and intelligent processing on edge servers(ES).However,securely distributing encrypted data stored in the cloud to terminals that meet decryption requirements has become a prominent research ***,managing attributes,including addition,deletion,and modification,is a crucial issue in the access control scheme for *** address these security concerns,a trust-based ciphertext-policy attribute-based encryption(CP-ABE)device access control scheme is proposed for RES(TB-CP-ABE).This scheme effectivelymanages the distribution and control of encrypted data on the cloud through robust attribute key *** introducing trust management mechanisms and outsourced decryption technology,the ES system can effectively assess and manage the trust worthiness of terminal devices,ensuring that only trusted devices can participate in data exchange and access sensitive ***,the ES system dynamically evaluates trust scores to set decryption trust thresholds,thereby regulating device data access permissions and enhancing the system’s *** validate the security of the proposed TB-CP-ABE against chosen plaintext attacks,a comprehensive formal security analysis is conducted using the widely accepted random oraclemodel under the decisional q-Bilinear Diffie-Hellman Exponent(q-BDHE)***,comparative analysis with other schemes demonstrates that the TB-CP-ABE scheme cuts energy/communication costs by 43%,and scaleswell with rising terminals,maintaining average latency below 50ms,ensuring real-time service *** proposed scheme not only provides newinsights for the secure management of RES but also lays a foundation for future secure energy solutions.

关键词： Access control renewable energy systems(RES) ciphertext-policy attribute-based encryption(CP-ABE) security

基于遥感技术的鄱阳湖采砂对水体透明度的影响

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生态学报 2008年第12期28卷 6113-6120页

作者：邬国锋崔丽娟武汉大学资源与环境科学学院&武汉大学教育部地理信息系统重点实验室武汉430079 中国林业科学研究院林业研究所&国家林业局林木培育重点实验室北京100091

采砂是一项具有巨大生态影响的经济活动。其引起沉积泥沙的再悬浮,降低水体透明度,减弱水下光环境以及产生一系列的生态影响。旨在利用遥感技术监测鄱阳湖自2001年开始的采砂活动对水体透明度的影响。时间序列的LANDSAT影像用于船只的... 详细信息

采砂是一项具有巨大生态影响的经济活动。其引起沉积泥沙的再悬浮,降低水体透明度,减弱水下光环境以及产生一系列的生态影响。旨在利用遥感技术监测鄱阳湖自2001年开始的采砂活动对水体透明度的影响。时间序列的LANDSAT影像用于船只的识别和同期的水体透明度反演,MODIS影像用于估计湖区2000～2005年6～10月期间水体透明度的动态变化。结果显示鄱阳湖北部自2001年以来随着船只数目的增加水体透明度显著下降。结合对船只最终目的地以及船只分布与水体透明度变化一致性等方面的分析,可以确认采砂是引起此区域水体透明度下降的主要原因。夏季频繁发生的长江江水倒灌推动鄱阳湖北部的浑浊水体向南移动,从而扩大采砂的影响范围至鄱阳湖中部,甚至南部。采砂繁荣了地方经济,同时也对鄱阳湖生态系统具有重大的负面影响。平衡经济发展与生态保护之间的关系,将因采砂而造成的负面影响下降到最低限度,使鄱阳湖的各种生态功能全面发挥是当务之急。

关键词：鄱阳湖遥感水体透明度采砂倒灌栖息地