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Uplink Grant-Free Pattern Division Multiple Access (GF-PDMA) for 5G Radio Access

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China Communications 2018年第4期15卷 153-163页

作者： Wanwei tang Shaoli Kang Bin ren Xinwei Yue School of Electronic and Information Engineering Beihang UniversityBeijing 100191，China Intelligence and Information Engineering College Tangshan UniversityTangshan 063000，China State Key Laboratory of Wireless Mobile Communications China Academy of Telecommunications TechnologyBeijing 100191，China

Massive machine type communication(m MTC) is one of the key application scenarios for the fifth generation mobile communication(5 G). Grant-free(GF) transmission can reduce the high signaling overhead in m MTC. Non-orthogonal multiple access(NMA) can support more users for m MTC than orthogonal frequency division multiple access(OFDMA). Applying GF transmission in NMA system becomes an active topic recently. The in-depth study on applying GF transmission in pattern division multiple access(PDMA), a competitive candidate scheme of NMA, is investigated in this paper. The definition, latency and allocation of resource and transmission mechanism for GF-PDMA are discussed in detail. The link-level and system-level evaluations are provided to verify the analysis. The analysis and simulation results demonstrate that the proposed GF-PDMA has lower latency than grant based PDMA(GB-PDMA), possesses strong scalability to confront collision and provides almost 2.15 times gain over GF-OFDMA in terms of supporting the number of active users in the system.

关键词： pattern division multiple access(PDMA) grant-free uplink massive machinetype communication (mMTC) 5G

A novel flexible nerve guidance conduit promotes nerve regeneration while providing excellent mechanical properties

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Neural Regeneration Research 2025年第7期20卷 2084-2094页

作者： Tong Li Quhan Cheng Jingai Zhang Boxin Liu Yu Shi Haoxue Wang Lijie Huang Su Zhang Ruixin Zhang Song Wang Guangxu Lu Peifu tang Zhongyang Liu Kai Wang Department of Orthopedics the Fourth Medical Center of Chinese PLA General HospitalBeijingChina Department of Training and Sports Medicine Characteristic Medical Center of Chinese People’s Armed Police ForceTianjinChina Medical School of Chinese PLA BeijingChina Key Laboratory of Bioactive Materials for the Ministry of Education College of Life SciencesNankai UniversityTianjinChina Department of Orthopedics Tianjin HospitalTianjinChina Department of Rehabilitation Medicine Er Quan Hospital of PAPWuxiJiangsu ProvinceChina

Autografting is the gold standard for surgical repair of nerve defects>5 mm in length;however,autografting is associated with potential complications at the nerve donor *** an alternative,nerve guidance conduits may be *** ideal conduit should be flexible,resistant to kinks and lumen collapse,and provide physical cues to guide nerve *** designed a novel flexible conduit using electrospinning technology to create fibers on the innermost surface of the nerve guidance conduit and employed melt spinning to align ***,we prepared disordered electrospun fibers outside the aligned fibers and helical melt-spun fibers on the outer wall of the electrospun fiber *** presence of aligned fibers on the inner surface can promote the extension of nerve cells along the *** helical melt-spun fibers on the outer surface can enhance resistance to kinking and compression and provide *** novel conduit promoted nerve regeneration and functional recovery in a rat sciatic nerve defect model,suggesting that it has potential for clinical use in human nerve injuries.

关键词： aligned fibers anti-kinking helical fibers nerve guidance conduit nerve regeneration peripheral nerve injury topological guidance

Symbol recognition and automatic conversion in GIS vector maps

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Petroleum Science 2016年第1期13卷 173-181页

作者： Dun-Long Liu zi-Yong Zhou Qian Wu Dan tang College of Software Engineering Chengdu University ofInformation and Technology Chengdu 610225 China State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum Beijing 102200China Sichuan Institute of Geological Engineering Investigation Chenzdu 610072 China

Symbols are considered as the language of a map;hence,accurate understanding of the meaning of symbols is crucial when obtaining geographical information from a map： the symbolisation of spatial data is of key importance in cartography.A geographical information system（GIS） provides a convenient mapping platform and powerful functions for spatial data symbolisation,while the presence of various mapping standards impedes the understanding of maps and sharing of map *** the other hand,the available GIS platforms find it difficult to deal with automatic conversion between maps and different mapping *** resolve this problem,an approach for symbol recognition and automatic conversion is proposed,and a conversion system based on the approach and the Arc GIS Engine platform is developed to realise automatic conversion between maps produced based on different mapping *** test these conversion effects of the proposed system,the petroleum sector is chosen as the research field and the mutual conversion of a map in practical work among the three mapping standards（*** Chinese Petroleum,Shell and USGS standards） governing this field is taken as a *** results show that the conversion system has a high conversion accuracy and strong applicability.

关键词： Symbol symbol matching powerful mutual resolve convenient hence polygon Petroleum

Pyrite Geochemistry and S-Hg Isotopes Reveal the Ore Genesis of the Hydrothermal Vein-type Cuiluan Ag-Pb-Zn Deposit in NE China

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Journal of Earth Science 2025年

作者： Lidong Zhang Changzhou Deng Yao tang Xinran Ni Bizheng Yang Shanshan Liang Weipeng Liu Jishuang Ding Xiaohui Zeng Heilongjiang Institute of Natural Resources Survey State Key Laboratory of Ore Deposit Geochemistry， Institute of Geochemistry， Chinese Academy of Sciences College of Earth and Planetary Sciences， Chengdu University of Technology

The Xing'an-Mongolian orogenic belt is an important Ag-Pb-Zn metallogenic province in China. The study on the genesis of the newly discovered Cuiluan hydrothermal vein-type Ag-Pb-Zn deposit located in the Lesser Xing'an Range， within the eastern of Xing'an-Mongolian orogenic belt， is pivotal in understanding the metallogenic mechanism and regularity of Ag-Pb-Zn deposits in this region. This study utilizes pyrite trace elements and sulfur isotopic geochemistry， and mercury isotope of rocks and ores to constrain the genesis of the Cuiluan deposit. Pyrite geochemical data show that Ag exists in the form of galena inclusions (Ag++(Bi3+， Sb3+) ? Pb2+) in the polymetallic sulfide stage， and independent Ag-bearing minerals （matildite and gustavite） precipitate during the main mineralization stage. The small varied δ34S values （3.24‰ - 4.94‰） of pyrites from four hydrothermal stages are within the range of magmatic S isotopes， indicating that the ore-forming fluid of the Cuiluan deposit mainly originated from the magma. The Δ199Hg values of the ores are close to 0‰， which are consistent with the Δ199Hg values of mantle， further indicating that the ore-forming materials came from the lithospheric mantle. Combined with the regional tectonic evolution， we conclude that the plate subduction of Paleo-oceans in NE China triggered the partial melting of metasomatized mantle. The mantle-derived magma rose along the deep fractures and evolved ore-forming fluids， and finally caused the formation of Cuiluan quartz vein-type Ag-Pb-Zn deposit in the shallow crust. Accompany with previous documents， we infer that the fractures in the large-scale “Granite Sea” in the Lesser Xing'an Range may have significant potential for vein-type Ag-Pb-Zn exploration.

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Calibration of the Solar X-ray Detector on-board the Macao Science Satellite-1B for Soft X-ray Detection

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Science China Earth Sciences 2025年第1期68卷 11-26页

作者： Man-Hei NG Xiaoping ZHANG Jianwu CHEN Yongqiang SHI Fuchang ZUO Wenxi PENG Weichun FU Liansheng LI Pengwei LUO Chi-Long tang Guozheng ZHANG Zhiwu MEI Li WANG Cunhui LI Jiaming OU Yanyan XU State Key Laboratory of Lunar and Planetary Sciences Macau University of Science and Technology China National Space Administration (CNSA) Macau Center for Space Exploration and Science Space Optoelectronic Measurement and Perception Laboratory Beijing Institute of Control Engineering Institute of High Energy Physics Chinese Academy of Sciences Science and Technology on Vacuum Technology and Physics Laboratory Lanzhou Institute of Physics

The Solar X-ray Detector(SXD) on-board the Macao Science Satellite-1B(MSS-1B) was successfully launched via the Chinese Long March-2C rocket on 21 May 2023, and commenced operations in early June of the same year. The MSS-1B/Soft X-ray Detection Units(SXDUs) employ two silicon drift detectors(SDDs), providing a wide range of energy spectra spanning from 0.7 to 24 keV. Notably, the SXDUs deliver a high-resolution capability of 0.14 keV@5.9 keV and operate with a time cadence of 1 second. Here, we perform thorough calibrations of the MSS-1B/SXDUs, employing a combination of ground experiments and simulations. In addition, quantitative analysis comparing the flux measurements obtained by the MSS-1B/SXDUs to the data collected by the Geostationary Operational Environmental Satellite(GOES), provides compelling evidence of their consistency. Furthermore, the preliminary spectral analysis results showcase the robustness and expected performance of the MSS-1B/SXDUs, unlocking their potential for facilitating the study of dynamic evolution of solar flares. Moreover, the innovative MSS-1B/Solar X-ray Detector facilitates concurrent observations of solar soft and hard X-rays, thereby making valuable contributions to the advancements in solar research.

关键词： Macao Science Satellite-1B (MSS-1B) Calibration Solar X-Ray Detector Spectrometer Soft X-rays Solar flares Solar abundances

Fracturing behavior of brittle solids containing 3D internal crack of different depths under ultrasonic fracturing

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International Journal of Mining Science and Technology 2022年第6期32卷 1245-1257页

作者： Haijun Wang Hanzhang Li Lei tang Jianchun Li Xuhua ren State Key Laboratory of Hydrology-Water Resource and Hydraulic Engineering Nanjing Hydraulic Research InstituteNanjing 210029China School of Civil Engineering Institute of Future Underground SpaceSoutheast UniversityNanjing 211186China College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing 210098China

Ultrasonic fracturing(UF)can be used to form crack networks for oil or gas in the mining industry and hard rock *** this paper,the three-dimensional internal laser-engraved crack method(3DILC)is introduced to make penny-shaped internal crack within the samples without any damage to the *** experiments were performed on the transparent samples with internal cracks at different *** macro-and micro-fracture fractography characteristics were focused on and analyzed in *** on fractography,the mechanisms of the UF were *** propagation paths of cracks of different depths were simulated based on the Paris fatigue model and compared with experimental *** results show that the 3D-ILC method is a powerful tool for the experimental research on the internal crack propagation in the *** the action of ultrasonic field,fractography shows the characteristics of beach marks,lance-like pattern,rime-like pattern and glass *** can be judged that the mechanisms of UF include high cycle fatigue fracture,shear fracture,and *** results of the numerical simulation using the Paris fatigue model are consistent with the experimental results.

关键词： 3D-ILC method 3D internal crack Ultrasonic fracturing Fracture mechanics Ultrasonic fatigue Paris fatigue model

Nanowires-assembled WO3 nanomesh for fast detection of ppb-level NO2 at low temperature

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Journal of Advanced Ceramics 2020年第1期9卷 17-26页

作者： Di LIU Xiaowei ren Yesheng LI zilong tang Zhongtai ZHANG State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China

Hierarchical WO3 nanomesh,assembled from single-crystalline WO3 nanowires,is prepared via a hydrothermal method using thiourea(Tu)as the morphology-controlling *** of the hierarchical architecture comprising of WO3 nanowires takes place via Ostwald ripening mechanism with the growth *** sensor based on WO3 nanomesh has good electrical conductivity and is therefore suitable as NO2 sensing *** WO3 nanomesh sensor exhibited high response,short response and recovery time,and excellent selectivity towards ppb-level NO2 at low temperature of 160℃.The superior gas performance of the sensor was attributed to the high-purity hexagonal WO3 with high specific surface area,which gives rise to enhanced surface adsorption sites for gas *** electron depletion theory was used for explaining the NO2-sensing mechanism by the gas adsorption/desorption and charge transfer happened on the surface of WO3 nanomesh.

关键词： WO3 nanomesh controlling agent NO2 sensing charge transfer

Phase coupling synchronization of FHN neurons connected by a Josephson junction

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Science China(Technological Sciences) 2020年第11期63卷 2328-2338页

作者： ZHANG Yin WANG ChunNi tang Jun MA Jun ren GuoDong Department of Physics Lanzhou University of TechnologyLanzhou 730050China School of Physics China University of Mining and TechnologyXuzhou 221116China School of Science Chongqing University of Posts and TelecommunicationsChongqing 430065China

Avariety of nonlinear circuits can be tamed to reproduce the main dynamical properties in neural activities for biological neurons while designing reliable artificial synapses for connecting these neural circuits becomes a *** this paper,a Josephson junction is used to build coupling channel for connecting two FitzHugh-Nagumo neural circuits driven by periodical voltage *** hybrid synapse is designed by using a linear resistor paralleled with a Josephson junction,which can estimate the effect of external magnetic field by generating additive phase error between the ***,it activates nonlinear coupling due to phase diversity in the Josephson *** coupled circuits are estimated in dimensionless dynamical systems by applying scale transformation on the variables and parameters in neural *** fact,the intrinsic parameters of coupling channel are adjusted to detect the occurrence of *** analysis is calculated to predict and confirm the occurrence of synchronization between two neural *** is found that synchronization can be stabilized between two FHN neural circuits by selecting appropriate values for parameters in the Josephson junction involved in the coupling *** gives useful guidance for implementing artificial synapse for signal processing in neural circuits.

关键词： neuron synchronization hybrid synapse neural circuit bifurcation

Time-synchronous-averaging-spectrum based on super-resolution analysis and application in bearing fault signal identification

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第7期25卷 573-585页

作者： Zengle ren Yuan WANG Huiyue tang Xin'an CHEN Wei FENG Guangdong Provincial Key Laboratory of Construction Robotics and Intelligent Construction Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen518055China Shenzhen EBORAIL Technology Co. Ltd.Shenzhen518038China National Supercomputing Center in Shenzhen Shenzhen518055China State Key Lab of Rail Traffic Control and Safety Beijing Jiaotong UniversityBeijing100044China University of Chinese Academy of Sciences Beijing100190China Shenzhen University of Advanced Technology Shenzhen518107China

Time-synchronous-averaging(TSA)is based on the idea of denoising by averaging,and it extracts the periodic components of a quasiperiodic signal and keeps the extracted waveform *** paper studies the mathematical properties of TSA,where three propositions are given to reveal the nature of *** paper also proposes a TSA-spectrum based on super-resolution analysis and it decomposes a signal without using any base *** contrast to discrete Fourier transform spectrum(DFT-spectrum),which is a spectrum in frequency domain,TSA-spectrum is a period-based spectrum,which can present more details of the cross effects between different periodic components of a quasiperiodic ***,a case study is carried out using bearing fault analysis to illustrate the performance of TSA-spectrum,where the rotation speed fluctuation of the shaft is estimated,which is about 0.12 ms *** extracted fault signals are presented and some insights are *** believe that this paper can provide new motivation for TSA-spectrum to be widely used in applications involving quasiperiodic signal processing(QSP).

关键词： Time-synchronous-averaging(TSA) Spectrum Quasiperiodic signal processing(QSP) Super-resolution analysis Bearingfaultdetection