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Collaborative beamforming based on directional perturbation using one bit feedback

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Journal of Systems Engineering and Electronics 2016年第3期27卷 549-554页

作者： Haifen Yang Ning Ding Zhi Zheng Shuisheng Lin Zhongpei Zhang guangjun Li School of Communication & Information Engineering University of Electronic Science and Technology of China

A novel collaborative beamforming algorithm is proposed in a wireless communication system with multiple transmitters and one receiver. All transmitters take part in the collaboration and the weighted message is transmitted simultaneously. In order to maximize the beamforming gain, the transmitters use one bit feedback information to adjust the phase offset. It tracks the direction in which the signal strength at the receiver can increase. The directional search and perturbation theory is used to achieve the phase alignment. The feasibility of the proposed algorithm is proved both experimentally and theoretically. Simulation results show that the proposed algorithm can improve the convergent speed of the phase alignment.

关键词： collaborative beamforming one-bit feedback directional perturbation convergent speed

Convective high-speed flow and field-aligned high-speed flows explored by TC-1

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Chinese Science Bulletin 2008年第15期53卷 2371-2375页

作者： ZHAng LingQian LIU ZhenXing MA Zhiwei w. BAUMJOHANN M.w. DUNLOP w.ng guangjun w.ng Xiao H. REME C. CARR Centre for Space Science and Applied Research Chinese Academy of Sciences Beijing 100080 China Institute for Fusion Theory and Simulation Zhejiang University Hangzhou 310027 China Space Research Institute Austrian Academy of Sciences 68042 Graz Austria Space Sciences Division Rutherford Appleton Laboratory Chilton Didcot Oxfordshire OX11 0QX United Kingdom Centre d'Etude Spatiale des Rayonnements F-78140 Toulouse Codex France Imperial College London SW7 2BZ United Kingdom

From June 1, 2004 to October 31, 2006, a total 465 high-speed flow events are observed by the TC-1 satellite in the near-Earth region (?13 RE < x < ?9 RE, |Y |<10 RE, |Z|<5 RE). Based on the angle between the flow and... 详细信息

From June 1, 2004 to October 31, 2006, a total 465 high-speed flow events are observed by the TC-1 satellite in the near-Earth region (?13 RE ngle between the flow and the magnetic field, the high-speed flow events are further divided into two types, that is, field-aligned high-speed flow (FAHF) in the plasma sheet boundary and convective bursty bulk flow (BBF) in the center plasma sheet. Among the total 465 high-speed flow events, there are 371 FAHFs, and 94 BBFs. The CHF are mainly concentrated in the plasma sheet, the intersection angle between the flow and the magnetic field is larger, the magnetic field intensity is relatively weak. The FHF are mainly distributed near the boundary layer of the plasma sheet, the intersection angle between the flow and magnetic field is smaller, and the magnetic field intensity is relatively strong. The convective BBFs have an important effect on the substorm.

关键词：高速流对流磁场地球科学

Enhancement the photovoltaic performance of conjugated polymer based on simple head-to-head alkylthio side chains engineered bithiophene

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Chinese Chemical Letters 2020年第9期31卷 2459-2464页

作者： Zuoji Liu Chengjia Bao guangjun Zhang Kai Zhang Gangtie Lei Qiang Zhang Qiang Peng Yu Liu School of Materials Science and Engineering Jiangsu Engineering Laboratory of Light-Electricity-Heat Energy-Converting Materials and ApplicationsJiangsu Collaborative Innovation Center of Photovoltaic Science and EngineeringNational Experimental Demonstration Center for Materials Science and EngineeringChangzhou UniversityChangzhou 213164China College of Chemistry Key Lab of Environment-Friendly Chemistry and Application in the Ministry of EducationXiangtan UniversityXiangtan 411105China Key Laboratory of Green Chemistry and Technology of Ministry of Education College of Chemistryand State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610065China

In this article,three novel and simple molecular structure with donor-acceptor(D-A) type copolymers via only head-to-head alkoxy(OR) and/or alkylthio(SR) side chains onto the bithiophene(BT) as donor units and fluorinated benzotriazole(FBTA) as acceptor unit,namely,PBTOR-FBTA,PBTOSR-FBTA and PBTSRFBTA,were successfully designed and *** impacts of sulfur-oxygen(S…O) or sulfur-sulfur(S-S) noncovalent interactions on their physicochemical properties,molecular stacking,carrier mobility,morphologies of blend films,as well as their photovoltaic performance were deeply and systematically *** introduction of SR side-chains suddenly lowered the highest occupied molecular orbital(HOMO) energy levels,blue-shifted absorption,enhanced π-π stacking,as well as improved morphology of the photoactive layer blends in comparison with the re ference polymer without SR *** solar cells(PSCs) were fabricated to estimate their photovoltaic performance of the *** an optimized blend ratio of PBTSR-FBTA:PC71BM(1:0.8,w/w),the PBTSR-FBTAbased device exhibits a higher power conversion efficiency(PCE) of 6.25%,which is about 3.34 and 1.87 folds than that of the PBTOR-FBTA and PBTOSR-FBTA-based devices,*** research results demonstrate that the modification of the simple and low-cost SR side chains is an effective strategy to improve the photovoltaic performance of the polymers.

关键词： Bithiophene Fuorobenzotriazole Alkoxy side chain Alkylthio side chain Polymer solar cells

A Dynamic Multi-ary Query Tree Protocol for Passive RFID Anti-collision

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Computers, Materials & Continua 2022年第9期72卷 4931-4944页

作者： Gang Li Haoyang Sun Zhenbing Li Peiqi wu Daniele Inserra Jian Su Xiaochuan Fang guangjun wen Centre for RFIC and System School of Information and Communication EngineeringUniversity of Electronic Science and Technology of ChinaChengdu611731P.R.China Nanjing University of Information Science&Technology Nanjing210044China Queen Mary University of London LondonUnited Kingdom

In this paper,a dynamic multi-ary query tree(DMQT)anti-collision protocol for Radio Frequency Identification(RFID)systems is proposed for large scale passive RFID tag *** proposed DMQT protocol is based on an iterative process between the reader and tags which identifies the position of collision bits through map commands and dynamically encodes them to optimize slots allocation through query *** this way,the DMQT completely eliminates empty slots and greatly reduces collision slots,which in turn reduces the identification time and energy *** addition and differently to other known protocols,the DMQT does not need to estimate the number of tags,reducing the protocol implementation complexity and eliminating the uncertainty caused by the estimation algorithm.A numerical analysis shows that DMQT has better performance than other algorithms for a number of tags larger than ***,when the number of tags is 2000 and the tag identity(ID)length is 128 bits,the total identification time is 2.58 s and the average energy cost for a tag identification is 1.2 mJ,which are 16.9%and 10.4%less than those of state-of-the-art algorithms,*** addition,a DMQT extension based on ACK command has also been presented to deal with capture effect and avoid missing identification.

关键词： Anti-collision DMQT RFID dynamic multi-ary query seamless identification

Pore-Fracture Distribution Heterogeneity of Shale Reservoirs Determined by using HPMI and LPN_(2 )GA Tests

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Acta Geologica Sinica(English Edition) 2022年第5期96卷 1659-1672页

作者： ZHAng Junjian QIN Zhengyuan HAN Yanning w.ng Huaimeng HOU Maoguo YAN Gaoyuan FEng guangjun ZHAng Xiaoyang YIN Tingting ZHAng Hainan wEN Shupeng College of Earth Sciences&Engineering Shandong University of Science and TechnologyQingdaoShandong 266590China School of Resources and Earth Science China University of Mining and TechnologyXuzhouJiangsu 221116China Nottingham Geospatial Institute Faculty of EngineeringUniversity of NottinghamNottinghamNG72TUUK The First Exploration Team of Shandong Province Coal Geology Bureau ShandongQingdaoShandong 266000 General Institute of Chemical Geology Survey of CCGMB Beijing 100013China School of Geosciences China’s University of Petroleum(East China)QingdaoShandong 266580China 113 Team of Guizhou Coal Geology Bureau Guiyang 550000China

The compressibility of shale matrix reflects the effects of reservoir lithology, material composition, pore structure and tectonic deformation. It is important to understand the factors that influence shale matrix compressibility(SMC) and their effects on pore size distribution(PSD) heterogeneity in order to evaluate the properties of unconventional *** this study, the volumes of pores whose diameters were in the range 6–100 nm were corrected for SMC for 17 shale samples from basins in China using high-pressure mercury intrusion and low-temperature nitrogen gas adsorption analyses,in order to investigate the factors influencing the SMC values. In addition, the variations in fractal dimensions before and after pore volume correction were determined, using single and multifractal models to explain the effects of SMC on PSD heterogeneity. In this process, the applicability of each fractal model for characterizing PSD heterogeneity was determined using statistical analyses. The Menger and Sierpinski single fractal models, the thermodynamic fractal model and a multifractal model were all used in this study. The results showed the follow.ng. The matrix compression restricts the segmentation of the fractal dimension curves for the single fractal Menger and Sierpinski models, which leads to a uniformity of PSD heterogeneity for different pore diameters. However, matrix compression has only a weak influence on the results calculated using a thermodynamic model. The SMC clearly affects the multifractal value variations, show.ng that the fractal dimension values of shale samples under matrix compression are small. Overall PSD heterogeneity becomes small for pores with diameters below 100 nm and the SMC primarily affects the PSD heterogeneity of higher pore volume areas. The comparison of fractal curves before and after correction and the variance analysis indicate that the thermodynamic model is applicable to quantitatively characterize PSD heterogeneity of shale col

关键词： shale reservoirs matrix compressibility pore structure fractal dimension multifractal

Highly sensitive electrochemical determination of rutin based on the synergistic effect of 3D porous carbon and cobalt tungstate nanosheets

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Journal of Pharmaceutical Analysis 2022年第3期12卷 453-459页

作者： guangjun Feng Yang Yang Jiantao Zeng Jun Zhu Jingjian Liu Lun wu Zhiming Yang Guanyi Yang Quanxi Mei Qinhua Chen Fengying Ran Shenzhen Baoan Authentic TCM Therapy Hospital Shenzhen518101China Sinopharm Dongfeng General Hospital Hubei University of MedicineShiyanHubei442008China Shenzhen Hospital of Integrated Traditional Chinese and western Medicine Shenzhen518101China

Rutin,a flavonoid found in fruits and vegetables,is a potential anticancer compound with strong anticancer ***,electrochemical sensor was developed for the detection of *** this study,CowO_(4) nanosheets were synthesized via a hydrothermal method,and porous carbon(PC)was prepared via high-temperature *** preparation of the materials was confirmed,and characterization was performed by transmission electron microscopy,scanning electron microscopy,and X-ray photoelectron spectroscopy.A mixture of PC and CowO_(4) nanosheets was used as an electrode modifier to fabricate the electrochemical sensor for the electrochemical determination of *** 3D CowO_(4) nanosheets exhibited high electrocatalytic activity and good *** has a high surface-to-volume ratio and superior ***,the hydrophobicity of PC allows large amounts of rutin to be adsorbed,thereby increasing the concentration of rutin at the electrode *** to the synergistic effect of the 3D CowO_(4) nanosheets and PC,the developed electrochemical sensor was employed to quantitively determine rutin with high stability and *** sensor showed a good linear range(5-5000 ng/mL)with a detection limit of 0.45 ng/*** developed sensor was successfully applied to the determination of rutin in crushed tablets and human serum samples.

关键词： Rutin Electrochemical detection CowO_(4)nanosheets Porous carbon Sensor

Soil respiration dynamics in Cinnamomum camphora forest and a nearby Liquidambar formosana forest in Subtropical China

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Chinese Science Bulletin 2010年第16期55卷 736-743页

作者： TIAN DaLun w.ng guangjun YAN wenDe XIAng wenHua PEng ChangHui Faculty of Life Science and Technology Central South University of Forestry & Technology Changsha 410004 China Institut des sciences de l'environnement Departement des sciences biologiques Universite du Quebec a Montreal Montreal QC H3C 3P8 Canada

Climate change can significantly affect carbon cycling of forest *** diurnal and seasonal dynamics of soil respiration (Rs) in Cinnamomum camphora and Liquidambar formosana forests were investigated by using infrared gas exchange analyzer of Li-Cor 6400-09 each month in *** temperature and moisture were also *** variations in Rs varied with daily soil temperature in the two *** the grow.ng season,soil respiration peaked on July 28 due to higher soil temperature and moisture *** Rs variations were predominantly influenced by soil *** soil respirations in *** and *** forests were strongly related to soil temperature (x) at 5-cm depth (Rs=0.1598e 0.1377x (R 2=0.9289,P=0.001) and Rs=0.2177e 0.0962x (R 2=0.927,P=0.000)),while annual mean Rs rate was 2.614 and 1.397 μmol m-2 s-1 and Q 10 values were 3.96 and 2.62 for the two forests,***,Rs was not influenced by seasonal changes in soil moisture (w) in the two forests in *** developed two equations (Rs=-0.020w 2 +0.497w+0.562 (R 2=0.109,P>0.05),Rs=-0.001w 2 +0.072w +0.731(R 2=0.053,P>0.05)) to describe the relationship between Rs and soil moisture.A positive relationship between Rs and soil moisture were observed when soil moisture was below 12.43% and 18.00%,but when soil moisture exceeded threshold values of 12.43% and 18.00%,soil moisture became the restraint factor for ***-term observations of soil respiration and moisture are required to understand the temporal dynamics of soil respiration.

关键词：亚热带森林土壤呼吸中国树林

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Improved Magnetic Coupling Resonance wireless Power Transfer System

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Improved Magnetic Coupling Resonance Wireless Power Transfer...

第三十九届中国控制会议

作者： guangjun w.ng Jianhui Sun School of Automation China University of Geosciences China Hubei key Laboratory of Advanced Control and Intelligent Automation for Complex System

For the power supply of spaceborne cameras on two-body satellites, an improved magnetic coupling resonant wireless power transfer system(wPT) is proposed. By establishing the equivalent circuit model of wPT system, the influence of topology model and high-Q repeating coil on system performance is analyzed. Finally, the correctness of theory and analysis was verified by experiments. The experimental results show that when the transmission distance of the improved wPT system is 11 cm, the load can receive 18.66 w of power and the transmission efficiency is 69%. Compared with the traditional two-coil wPT system,the system has a significant improvement in transmission distance, transmission power, and transmission efficiency, and can meet the technical requirements of spaceborne cameras in transmission distance, transmission power and transmission efficiency.

关键词： Magnetic coupling resonance wPT Transmission distance Transmission power Transmission efficiency

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双端泵浦保偏光纤激光器

强激光与粒子束 2011年第4期23卷 863-865页

作者：任广军姚建铨天津理工大学电子信息工程学院薄膜电子与通信器件天津市重点实验室天津300384 天津大学精密仪器与光电子工程学院激光与光电子研究所光电信息科学技术教育部重点实验室天津300072

以两台808 nm半导体激光器LD1和LD2为泵浦源,对光纤激光器双端泵浦进行了研究,获得了6.5 w的激光输出。实验分别测出了LD1和LD2半导体激光器单端泵浦和双端泵浦时的输出功率,对双端泵浦输出功率与单端泵浦功率之和进行了比较,利用双端... 详细信息

以两台808 nm半导体激光器LD1和LD2为泵浦源,对光纤激光器双端泵浦进行了研究,获得了6.5 w的激光输出。实验分别测出了LD1和LD2半导体激光器单端泵浦和双端泵浦时的输出功率,对双端泵浦输出功率与单端泵浦功率之和进行了比较,利用双端泵浦提高了泵浦效率和输出激光功率。同时测量了输出激光的偏振度,通过计算得到双端泵浦输出激光的偏振度为0.5。

关键词：激光技术光纤激光器双端泵浦保偏