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Application of deep learning to estimate stratospheric gravity wave potential energy

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Earth and Planetary Physics 2022年第1期6卷 70-82页

作者： yue Wu zheng Sheng XinJie Zuo College of Meteorology and Oceanology National University of Defense TechnologyChangsha 410073China Northwest Institute of Nuclear Technology Xi’an 710024China High-tech Institute Fan Gong-ting South Street on the 12thQingzhou 262500China

One of the most important dynamic processes in the middle and upper atmosphere,gravity waves(GWs)play a key role in determining global atmospheric *** wave potential energy(GW Ep)is an important parameter that characterizes GW intensity,so it is critical to understand its global *** this paper,a deep learning algorithm(DeepLab V3+)is used to estimate the stratospheric GW *** deep learning model inputs are ERA5 reanalysis datasets and GMTED2010 terrain *** Ep averaged over 20−30 km from 60°S−60°N,calculated by COSMIC radio occultation(RO)data,is used as the measured value corresponding to the model *** results show that(1)this method can effectively estimate the zonal trend of GW ***,the errors between the estimated and measured value of Ep are larger in low-latitude regions than in mid-latitude regions,possibly due to the large number of convolution operations used in the deep learning ***,the measured Ep has errors associated with interpolation to the grid;this tends to be amplified in low-latitude regions because the GW Ep is larger and the RO data are relatively sparse,affecting the training accuracy.(2)The estimated Ep shows seasonal variations,which are stronger in the winter hemisphere and weaker in the summer hemisphere.(3)The effect of quasi-biennial oscillation(QBO)can be clearly observed in the monthly variation of estimated GW Ep,and its QBO amplitude may be less than that of the measured Ep.

关键词： deep learning stratospheric gravity wave potential energy

Compression loading of osteoclasts attenuated micro RNA-146a-5p expression,which promotes angiogenesis by targeting adiponectin

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Science China(Life Sciences) 2022年第1期65卷 151-166页

作者： yue Wang Yunfei zheng Weiran Li Department of Orthodontics Peking University School and Hospital of StomatologyBeijing 100081China

Osteoclastogenesis in alveolar bone induced by compression stress triggers orthodontic tooth *** stress also stimulates angiogenesis,which is essential for ***,the effects of osteoclastogenesis induced by compression on angiogenesis are poorly *** vivo,we found the markers of angiogenesis increased during orthodontic bone *** vitro,osteoclast-derived exosomes increased proliferation,migration,and tube formation of human umbilical vein endothelial cells(HUVECs),as well as expression of vascular endothelial growth factor and *** promotive effects of exosomes derived from compressed osteoclasts were greater than those derived from osteoclasts without ***,we analyzed changes in the micro RNA transcriptome after compression stress and focused on micro RNA146 a-5 p(mi R-146 a),which was significantly decreased by *** of an inhibitor of mi R-146 a stimulated angiogenesis of HUVECs while mi R-146 a mimics repressed ***(ADP)was confirmed to be a target of mi R-146 a by dual luciferase reporter *** HUVECs treated with exosomes,we detected increased ADP which promoted *** of ADP in HUVECs reduced the promotive effects of *** results demonstrate that the decreased mi R-146 a observed in osteoclasts after compression promotes angiogenesis by targeting ADP,suggesting a novel method to interfere with bone remodeling induced by compression stress.

关键词： micro RNA-146a-5p adiponectin angiogenesis compression stress osteoclastogenesis exosomes

HetNets Under Decoupled Uplink and Downlink Access with UE Random Discontinuous Transmission: Local Delay and Energy Efficiency

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China Communications 2024年第3期21卷 205-216页

作者： Zhang yue zheng Fuchun Luo Jingjing School of Electronic and Information Engineering Harbin Institute of Technology(Shenzhen)Shenzhen 518055China

Due to the limited uplink capability in heterogeneousnetworks (HetNets), the decoupled uplinkand downlink access (DUDA) mode has recently beenproposed to improve the uplink performance. In thispaper, the random discontinuous transmission (DTX)at user equipment (UE) is adopted to reduce the interferencecorrelation across different time slots. By utilizingstochastic geometry, we analytically derive themean local delay and energy efficiency (EE) of an uplinkHetNet with UE random DTX scheme under theDUDA mode. These expressions are further approximatedas closed forms under reasonable *** results reveal that under the DUDA mode, there isan optimal EE with respect to mute probability underthe finite local delay constraint. In addition, with thesame finite mean local delay as under the coupled uplinkand downlink access (CUDA) mode, the HetNetsunder the DUDA mode can achieve a higher EE witha lower mute probability.

关键词： decoupled uplink and downlink access(DUDA) heterogeneous networks(HetNets) random discontinuous transmission(DTX) stochastic geometry

A new approach for inversion of receiver function for crustal structure in the depth domain

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Earth and Planetary Physics 2022年第1期6卷 83-95页

作者： TianYu zheng YuMei He yue Zhu Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of Sciences(CAS)Beijing 100029China University of Chinese Academy of Sciences Beijing 100049China

A method for reconstructing crustal velocity structure using the optimization of stacking receiver function amplitude in the depth domain,named common conversion amplitude(CCA)inversion,is *** conversion amplitude in the depth domain,which represents the impedance change in the medium,is obtained by assigning the receiver function amplitude to the corresponding conversion position where the P-to-S conversion *** the conversion amplitude variation with depth as an optimization objective,imposing reliable prior constraints on the structural model frame and velocity range,and adopting a stepwise search inversion technique,this method efficiently weakens the tendency of easily falling into the local extremum in conventional receiver function *** tests show that the CCA inversion can reconstruct complex crustal velocity structures well and is especially suitable for revealing crustal evolution by estimating diverse velocity *** performance in reconstructing crustal structure is superior to that of the conventional receiver function imaging method.

关键词： crustal imaging receiver function depth domain inversion

Constructing Odd-Variable Rotation Symmetric Boolean Functions with Optimal Algebraic Immunity and High Nonlinearity

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Chinese Journal of Electronics 2019年第1期28卷 45-51页

作者： ZHAO Qinglan HAN gang zheng Dong LI Xiangxue School of Information Security Engineering Shanghai Jiaotong University National Engineering Laboratory for Wireless Security Xi'an University of Post and Telecommunications College of Electronic Information Northwestern Polytechnical University School of Computer Science and Technology East China Normal University

Rotation symmetric Boolean functions(RSBFs) have attracted widespread attention due to their good cryptographic properties. We present a new construction of RSBFs with optimal algebraic immunity on odd number of variables. The nonlinearity of the new function is much higher than other best known RSBFs with optimal algebraic immunity. The algebraic degree of the constructed n-variable RSBF can achieve the upper bound n-1 when n/2 is odd or when n/2 is a power of 2 for n≥*** addition, the constructed function can possess almost perfect immunity to fast algebraic attacks for n=11, 13, 15.

关键词： Cryptography Boolean functions Algebraic immunity Nonlinearity Algebraic attack

Effects of phase change material(PCM)-based nanocomposite additives on thermal decomposition and burning characteristic of high energy propellants containing RDX

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Defence Technology（防务技术） 2022年第4期18卷 557-566页

作者： En-fa Fu Na Sun zheng-gang Xiao Key Laboratory of Special Energy Materials Ministry of Education School of Chemical Engineering Nanjing University of Science and Technology

A kind of phase change material(PCM)-based nanocomposite was prepared and added into high energy propellants containing RDX as additives to investigate its effect on thermal decomposition and burning characteristic of high energy *** effect of PCM-based nanocomposites on thermal decomposition of high energy propellants is investigated by TG/DSC-FTIR-MS *** to the delayed protection effect(PCM-based nanocomposites can absorb lots of heat at the range of certain temperature when it undergoes structure change or phase transitions)of PCM-based nanocomposites under the thermal decomposition condition,the thermal stability of high energy propellants modified with PCMbased nanocomposites is *** the same time,the concentration of N2,NO2,H2O and CO_(2)is increased during thermal decomposition of high energy propellants whereas NO and CO is *** burning gaseous products and burning characteristic of high energy propellants are studied by the combination of closed bomb test and Fourier transform infrared *** main burning gaseous products are N2,CO_(2),CO,H2O,CH4,*** the high energy propellant modified with PCM-based nanocomposites,the concentration of CH4is increased while CO,CO_(2) and H2O is decreased under the high-pressure burning *** progressivity factor of high energy propellants is increased by22.2%compared with the control sample while the maximum pressure is merely decreased 1.25%after the addition of the PCM-based nanocomposite,thus PCM-based nanocomposites can be used to adjust the burning process and improve the burning progressivity of high energy *** study is expected to boost the practical application of PCM-based nanocomposite to the propellant formulation and effectively control the burning characteristic of high energy propellants.

关键词： Phase change material Propellants Nanocomposite Thermal decomposition Burning

Heterogeneous Image Knowledge Driven Visual Perception

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IEEE/CAA Journal of Automatica Sinica 2024年第1期11卷 255-257页

作者： Lan Yan Wenbo zheng Fei-yue Wang IEEE the College of Computer Science and Electronic Engineering Hunan UniversityChangsha 410082China the School of Computer Science and Artificial Intelligence Wuhan University of TechnologyWuhan 430070China the State Key Laboratory for Management and Control of Complex Systems Institute of AutomationChinese Academy of SciencesBeijing 100190China

Dear Editor,This letter is concerned with visual perception closely related to heterogeneous *** the huge challenge brought by different image modalities,we propose a visual perception framework based on heterogeneous image knowledge,i.e.,the domain knowledge associated with specific vision tasks,to better address the corresponding visual perception problems.

关键词： Visual visual knowledge

Design and Implementation of Nonlinear Precoding for MIMO-SDMA Toward 6G Wireless

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China Communications 2024年第1期21卷 69-87页

作者： Chaowu Wu yue Xiao Shu Fang gang Wu National Key Laboratory of Wireless Communications University of Electronic Science and Technology of ChinaChengdu 611731China

In this paper,we present a novel and robust nonlinear precoding(NLP)design and detection structure specifically tailored for multiple-input multipleoutput space division multiple access(MIMO-SDMA)systems toward 6G *** approach aims to effectively mitigate the impact of imperfect channel estimation by leveraging the channel fluctuation mean square error(MSE)for reconstructing a highly accurate precoding matrix at the ***,we introduce a simplified receiver structure that eliminates the need for equalization,resulting in reduced interference and notable enhancements in overall system *** conduct both computer simulations and experimental tests to validate the efficacy of our proposed *** results reveals that the proposed NLP scheme offers significant performance improvements,making it particularly well-suited for the forthcoming 6G wireless.

关键词： MIMO-SDMA nonlinear precoding Tomlinson-Harashima precoding(THP) vector perturbation(VP)

Non-isothermal kinetics of synthesizing vanadium nitride by one-step method

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Rare Metals 2015年第10期34卷 738-743页

作者： Jiang Dong yue Yu zheng-Liang Xue School of Materials and Metallurgy Wuhan University of Science and Technology

Vanadium nitride was synthesized by one-step method using V2O5 and carbon black as raw materials in nitrogen atmosphere. The phases of different reaction products prepared in different reaction temperatures were analyzed by X-ray diffraction(XRD), and the dynamic behavior of the process of synthesizing vanadium nitride(VN) by one-step method was studied with non-isothermal thermogravimetry. The mechanism function and kinetic parameters of reaction process were calculated by thermal gravimetric analyses(TGA), and the reaction rate equation was established. The XRD results show that for the samples tested with minimal VN after holding for 4 h at 1273 K, the main phase of products is VN at 1476 K, while some vanadium nitrides transform into vanadium carbides again over 1573 K. It is found that N2 is beneficial to stimulate reduction and proceed carbonization reaction,and the reduction and nitridation reaction can occur simultaneously. The activation energy of preparing VN by one-step method is 104.005 kJ·mol-1, and the frequency factor is 470.52 at 1280–1358 K, and 150.052 kJ·mol-1 and 2.35 9 104 at 1358–1426 K, respectively.

关键词： Vanadium nitride Reduction and nitridation Thermog