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Science China(Information Sciences) 2016年第10期59卷 152-168页

作者： hang ruan Lei Zhang Teng LONG Key Laboratory of Electronic and Information Technology in Satellite Navigation (Beijing Institute of Technology) Ministry of Education School of Information and Electronics Beijing Institute of Technology

Binary Offset Carrier(BOC) signals with high subcarrier rate such as Alt BOC(15,10) and cosBOC(15,2.5) have been adopted for the next generation of Global Navigation Satellite System(GNSS) to make full use of the allocated spectrum. However, the two main lobes of the BOC signals are tremendously separated in the frequency spectrum and the group delay of the two lobes are greatly dispersed due to ionospheric dispersion. The signals will suffer extremely severe distortion caused by the group delay dispersion including waveform ripples, power losses and correlation function asymmetries. In this paper, a novel time domain sinc interpolation based ionospheric dispersion compensation method is proposed to eliminate the distortion to the BOC ***, the time domain model of BOC signal under the dispersive ionosphere is developed. Afterwards, based on the model, the two signal main lobes are aligned by sinc interpolation so that the ionospheric dispersion effects are almost mitigated. Taking Galileo E5 Alt BOC(15,10) signal as an example, the performance of the proposed method is evaluated by simulation and test. The results show that the proposed method is able to more effectively compensate the ionospheric dispersion with fewer computational loads versus existing methods.

关键词： ionospheric dispersion sinc interpolation BOC code tracking bias high subcarrier rate

Pore Pressure Accumulation of Anisotropically Consolidated Soft Clay Subjected to Complex Loads Under Different Stress Paths

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China Ocean Engineering 2021年第3期35卷 465-474页

作者： WANG yu-ke WAN Yong-shuai ruan hang yu Xiang SHAO Jing-gan REN De-bo College of Water Conservancy Engineering Zhengzhou UniversityZhengzhou 450001China State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan 430071China Collaborative Innovation Center of Water Conservancy and Transportation Infrastructure Safety Zhengzhou 450001China State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116024China Henan Jiaoyuan Engineering Technology Co. LtdZhengzhou 450001China Yellow River yuanyang Bureau Yellow River Conservancy CommissionYuanyang 453500China

Owing to different influence factors of foundation soil,the initial stress state of the soil under various working conditions is *** simulate this situation,in this paper,a series of tests on undisturbed soft clay under pure principal stress axis rotation were carried out by using the hollow cylinder apparatus(HCA).The influence of initial consolidation angle ζ(the angle between the vertical direction and direction of the applied load in consolidation)and intermediate principal stress coefficient b on pore water pressure accumulation of undisturbed soft clay were mainly *** test results show that,during pure principal stress axis rotation,the pore water pressure accumulation of the undisturbed soft clay fluctuates and increases with the rotation of the major principal stress;the values of major principal stress anglesα,corresponding to the peak value of the pore water pressure in a certain cycle,are different with different initial consolidation angles;the pore water pressure accumulation of soft clay is greatly affected by the intermediate principal stress coefficient *** the fixed initial consolidation angle ζ,the variation trend of the maximum pore water pressure for each cycle is appropriately the same with different b *** the increase of cycles,the difference value of pore water pressure between b=0 and b=1 in each cycle increases gradually with different initial consolidation angles ζ.While with different initial consolidation anglesζ,the increase of the pore water pressure when b increases from 0 to 0.5 is different with that when b increases from 0.5 to 1;the variation of maximum pore water pressure withζis significantly affected by the value of b;the value of maximum pore water pressure increases with the cycle number increases under all test conditions,but the growth rate decreases *** the variation of maximum pore water pressure with the cycle number N is obviously influenced by both ζ and b.

关键词： anisotropical consolidation pure principal stress rotation soft clay pore water pressure

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乐昌市消费扶贫存在问题及对策刍探

广东水利电力职业技术学院学报 2021年第4期19卷 77-80页

作者：许华杰陈嘉奕杨右森何泽霆阮宇航广东水利电力职业技术学院广州510635

消费扶贫实践开辟了一条扶贫新路,极大程度解决了优质农特产品的销售问题,既满足了消费者的需求,又提升了贫困户脱贫致富的决心和动力。但实施中也存在产品产量不高、品质不一、销售群体狭窄等问题。对此,可通过行政手段支持引导,扶持... 详细信息

消费扶贫实践开辟了一条扶贫新路,极大程度解决了优质农特产品的销售问题,既满足了消费者的需求,又提升了贫困户脱贫致富的决心和动力。但实施中也存在产品产量不高、品质不一、销售群体狭窄等问题。对此,可通过行政手段支持引导,扶持特色产业、拓宽销售渠道、形成规模经济,最终将消费扶贫转化为市场选择,实现全面小康到乡村振兴的有效衔接。

关键词：乐昌消费扶贫农特产品规模经济

Porous Organic Cage‑Based Quasi‑Solid‑State Electrolyte with Cavity‑Induced Anion‑Trapping Effect for Long‑Life Lithium Metal Batteries

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Nano-Micro Letters 2025年第2期17卷 376-386页

作者： Wei-Min Qin Zhongliang Li Wen‑Xia Su Jia‑Min Hu Hanqin Zou Zhixuan Wu Zhiqin ruan yue‑Peng Cai Kang Li Qifeng Zheng School of Chemistry South China Normal UniversityGuangzhou 510006People’s Republic of China Key Laboratory of Functional Metal‑Organic Compounds of Hunan Province College of Chemistry and Material ScienceHengyang Normal UniversityHengyang 421008People’s Republic of China Guangzhou Key Laboratory of Energy Conversion and Energy Storage Materials Guangzhou 510006People’s Republic of China

Porous organic cages(POCs)with permanent porosity and excellent host–guest property hold great potentials in regulating ion transport behavior,yet their feasibility as solid-state electrolytes has never been testified in a practical ***,we design and fabricate a quasi-solid-state electrolyte(QSSE)based on a POC to enable the stable operation of Li-metal batteries(LMBs).Benefiting from the ordered channels and cavity-induced anion-trapping effect of POC,the resulting POC-based QSSE exhibits a high Li+transference number of 0.67 and a high ionic conductivity of 1.25×10^(−4) S cm^(−1) with a low activation energy of 0.17 *** allow for homogeneous Li deposition and highly reversible Li plating/stripping for over 2000 *** a proof of concept,the LMB assembled with POC-based QSSE demonstrates extremely stable cycling performance with 85%capacity retention after 1000 ***,our work demonstrates the practical applicability of POC as SSEs for LMBs and could be extended to other energy-storage systems,such as Na and K batteries.

关键词： Porous organic cage Cavity-induced anion-trapping Quasi-solid-state electrolyte Homogeneous Li+flux Lithium metal battery

Ground Penetrating Radar (GPR) Identification Method for Agricultural Soil Stratification in a Typical Mollisols Area of Northeast China

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Chinese Geographical Science 2023年第4期33卷 664-678页

作者： ruan Weimin LIU Baojiang LIU Huanjun DONG hang SUI yueyu Northeast Institute of Geography and Agroecology Chinese Academy of SciencesChangchun 130102China University of Chinese Academy of Sciences Beijing 100049China

In order to achieve a rapid and accurate identification of soil stratification information and accelerate the development of smart agriculture,this paper conducted soil stratification experiments on agricultural soils in the Mollisols area of Northeast China using Ground Penetrating Radar(GPR)and obtained different types of soil with frequencies of 500 MHz,250 MHz,and 100 MHz *** soil profile data were obtained for 500 MHz,250 MHz,and 100 MHz antennas,and the dielectric properties of each type of soil were *** the image processing procedure,wavelet analysis was first used to decompose the pre-processed radar signal and reconstruct the high-frequency information to obtain the reconstructed signal containing the stratification ***,the reconstructed signal is taken as an envelope to enhance the stratification *** Hilbert transform is applied to the envelope signal to find the time-domain variation of the instantaneous frequency and determine the time-domain location of the ***,the dielectric constant of each soil horizon is used to obtain the propagation velocity of the electromagnetic wave at the corresponding position to obtain the stratification position of each soil *** research results show that the 500 MHz radar antenna can accurately delineate Ap/Ah,horizon and the absolute accuracy of the stratification is within 5 *** effect on the soil stratification below the tillage horizon is not apparent,and the absolute accuracy of the 250 MHz and 100 MHz radar antennas on the stratification is within 9 *** overwhelming majority of the overall calculation errors are kept to within 15%.Based on the three central frequency antennas,the soil horizon detection rate reaches 93.3%,which can achieve accurate stratification of soil profiles within 1 *** experimental and image processing methods used are practical and feasible;however,the GPR will show a missed detection for soil horizons with only s

关键词： soil stratification ground-penetrating radar profiling wavelet analysis envelope signal Northeast China

Researches on the Structure and Properties of Mullite Solid Solution Made from Industrial Waste

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Chinese Journal of Structural Chemistry 2006年第8期25卷 965-970页

作者： ruan yu-Zhong yu Yan WU Ren-Ping College of Materials Science and Engineering Fuzhou University Fuzhou 350002 China

The waste slag from aluminum profile factory and silicon fine powder from ferroalloy factory were utilized as the main raw materials to synthesize mullite solid solution Al4＋2xSi2-xO10-x/2, whose defect formation mechanism, crystalline phase composition, crystal cell parameters, microstructures and morphologies were characterized in detail by XRD and SEM. The results show that because of the ultrafine particle size of the materials, the content of mullite solid solution synthesized by this method is higher than that by regular method. Keywords： waste slag from aluminum factory, silicon fine powder, mullite, solid solution

关键词： waste slag from aluminum factory silicon fine powder mullite solid solution

Studies on the Structure and Properties of Multiphase Al_2O_3 Abrasion-resistant Ceramics

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Chinese Journal of Structural Chemistry 2006年第7期25卷 805-810页

作者： WU Ren-Ping yu Yan ruan yu-Zhong College of Materials Science and Engineering Fuzhou University Fuzhou 350002 China

The Al2O3 abrasion-resistant ceramics is successfully prepared by using waste aluminum sludge as the main raw material with the addition of a little clay, talc and barium carbonate. The crystal structure and microstructure of ceramic are characterized by means of XRD, SEM, etc., and the physical and mechanical properties are also tested. The results show that besides the phase of corundum, a little mullite, Mg-Al spinel and hyalophane phases also exist in the product. These phases are produced via reaction in-situ, which can inhibit the overgrowth of Al2O3 grain in grain boundary, and improve the integral property of the material.

关键词： Al2O3 ceramic crystal structure property in-situ synthesis

The Higgs signatures at the CEPC CDR baseline

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Chinese Physics C 2019年第2期43卷 5-11页

作者： hang Zhao Yong-Feng Zhu Cheng-Dong Fu Dan yu Man-Qi ruan Institute of High Energy Physics Chinese Academy of Sciences CAS Center for Excellence in Particle Physics Collaborative Innovation Center for Particles and Interactions University of Chinese Academy of Sciences

As a Higgs factory, the CEPC(Circular Electron-Positron Collider) project aims at precision measurements of the Higgs boson properties. A baseline detector concept, APODIS(A PFA Oriented Detector for the HIggS factory), has been proposed for the CEPC CDR(Conceptual Design Report) study. We explore the Higgs signatures for this baseline design with ■ Higgs events. The detector performance for reconstructing charged particles, photons and jets is quantified with H→μμ, γγ and jet final states, respectively. The resolutions of reconstructed Higgs boson mass are comparable for the different decay modes with jets in the final states. We also analyze the H→WW~* and ZZ* decay modes, where a clear separation between different decay cascades is observed.

关键词： CEPC Higgs boson full simulation

Simulation study on fluctuant flow stress scale effect

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第8期7卷 1343-1350页

作者： SHEN yu yu Hu-ping ruan Xue-yu National Die and Mold CAD Engmeering Research Center Shanghai Jiao Tong University Shanghai 200030 China

Crystal plasticity theory was used to simulate upsetting tests of different dimensions and grain size micro copper cylinders in this study on the fluctuant flow stress scale effect. Results showed that with the decrease of billet grain quantity, flow stress fluctuation is not always increased, but there is a maximum. Through this study, the fluctuant flow stress scale effect can be understood deeper, and relevant necessary information was obtained for further prediction and control of this scale effect and to design the microforming process and die.

关键词： Microforming Scale effect Numerical simulation Fluctuation

Signaling Mechanism for Modulation by GLP-1 and Exendin-4 of GABA Receptors on Rat Retinal Ganglion Cells

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Neuroscience Bulletin 2022年第6期38卷 622-636页

作者： Tao Zhang hang-Ze ruan Yong-Chen Wang yu-Qi Shao Wei Zhou Shi-Jun Weng Yong-Mei Zhong State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science Institutes of Brain ScienceFudan UniversityShanghai 200032.China

Glucagon-like peptide-1(GLP-1)is expressed in retinal neurons,but its role in the retina is largely ***,we demonstrated that GLP-1 or the GLP-1 receptor(GLP-1R;a G protein-coupled receptor)agonist exendin-4 suppressed-aminobutyric acid receptor(GABAR)-mediated currents through GLP-1Rs in isolated rat retinal ganglion cells(GCs).Pre-incubation with the stimulatory G protein(G,)inhibitor NF 449 abolished the exendin-4 *** exendin-4-induced suppression was mimicked by perfusion with 8-Br-cAMP(a cAMP analog),but was eliminated by the protein kinase A(PKA)inhibitor RpcAMP/***_exendin-4 effect was accompanied by an increase in[Ca2+];of GCs through the IP3-sensitive pathway and was blocked in Ca2+-free ***,when the activity of calmodulin(CaM)and CaMdependent protein kinase II(CaMKII)was inhibited,the exendin-4 effect was *** with this,exendin-4 suppressed GABAR-mediated light-evoked inhibitory postsynaptic currents in GCs in rat retinal *** results suggest that exendin-4-induced suppression may be mediated by a distinct G,/cAMP-PKA/IPs/Ca+/CaM/CaMKIl signaling pathway,following the activation of GLP-1Rs.

关键词： Glucagon-like peptide-1 Exendin-4 GABA current Retinal ganglion cells Neuromodulation