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基于储能电池的H桥功率模块对拖试验研究

科技资讯 2024年第7期22卷 52-55页

作者：郭志超陈杰张亚鹏谭雯董露赵俊强北京电力自动化设备有限公司北京100044

主要研究基于储能电池的H桥功率模块对拖试验相关内容。首先,介绍了主回路和控制回路拓扑设计,每个H桥功率模块直流侧均并联一个储能电池。其次,提出了整个试验系统的保护协调配合与动作原则,主控制器负责总体保护及保护的协调配合,功... 详细信息

主要研究基于储能电池的H桥功率模块对拖试验相关内容。首先,介绍了主回路和控制回路拓扑设计,每个H桥功率模块直流侧均并联一个储能电池。其次,提出了整个试验系统的保护协调配合与动作原则,主控制器负责总体保护及保护的协调配合,功率模块、水冷系统、BMS负责各自保护。最后,提出有功无功对拖控制策略以及具体试验流程,实现两个功率模块的有功和无功满功率试验。

关键词：功率模块 H 桥储能电池对拖试验

Review of Annual Progress from Nuclear Matter Phase Structure Group

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IMP & HIRFL Annual Report 2022年第1期 16-18页

作者： Qiu Hao zhang yapeng 不详

The Nuclear Matter Phase Structure Group at the Qurak Matter Research Center(QMRC)is focused on investigating the phase structure of Quantum Chromodynamics(QCD)matter and studying the properties of nuclear matter under extreme *** achieve these objectives,the group leverages heavy-ion collision(HIC)experiments,which enable the creation of hot and condensed nuclear matter in laboratory settings.

关键词： conditions. Structure extreme

Cosmic-ray Charge Measurement by DAMPE Plastic Scintillator Detector

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IMP & HIRFL Annual Report 2018年第1期 16-17页

作者： zhang yapeng Ding Meng 不详

Precisely measuring the energy spectra of cosmic-rays is vital to constrain the cosmic-ray production mechanism[1]and their propagation in the stellar medium[2].DArk Matter Particle Explorer(DAMPE)[3]is a high-resolution multi-purpose device for detecting cosmic-rays including electrons,γ-rays,protons and heavy ions in an energy range of a few GeV to 100 *** has been launched on December 17th,2015 and operates on a sun-synchronous orbit at the altitude of 500 *** consists of four sub-detectors:a Plastic Scintillator Detector(PSD),a Silicon-Tungsten Tracker(STK),a Bismuth Germanate Oxid Calorimeter(BGO)and a NeUtron Detector(NUD).

关键词： DAMP altitude Plastic

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断层破碎带形态对隧道围岩变形影响研究

市政技术 2024年第5期42卷 92-103页

作者：廖秋林蒋坪临武福美张亚鹏徐嘉彬宋国奥北京城建设计发展集团股份有限公司北京100037 北京城建轨道交通建设工程有限公司北京102600 中国矿业大学(北京)力学与建筑工程学院北京100083

断层破碎带具有围岩破碎、强度低等特点,极易引起隧道围岩发生大变形,进而诱发工程灾害。因此,依托重庆市郊铁路璧铜线云雾山隧道工程,采用PLAXIS3D数值分析软件,建立了隧道穿越不同形态断层破碎带计算模型。计算结果表明:断层破碎带倾... 详细信息

断层破碎带具有围岩破碎、强度低等特点,极易引起隧道围岩发生大变形,进而诱发工程灾害。因此,依托重庆市郊铁路璧铜线云雾山隧道工程,采用PLAXIS3D数值分析软件,建立了隧道穿越不同形态断层破碎带计算模型。计算结果表明:断层破碎带倾角和厚度对隧道围岩变形影响显著,断层走向线与隧道轴线夹角对隧道围岩变形影响较小。随着断层破碎带倾角的增大,受断层破碎带影响的范围明显缩小,隧道围岩竖向和水平位移值均逐渐减小,且当断层破碎带倾角为90°时,受断层破碎带影响的范围最小;随着断层破碎带厚度的增大,受断层破碎带影响的范围随之增大,围岩的竖向和水平位移值均逐渐增大,且当断层破碎带厚度为22 m时达到最大值。隧道正交穿越断层破碎带薄弱处时,围岩变形控制效果会更好。该研究成果可为山岭隧道穿越断层破碎带设计与施工提供一定的参考。

关键词：断层破碎带隧道围岩变形数值分析断层形态竖向位移水平位移

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An improved elastoplastic model for rocks and application to cyclic loading and unloading triaxial compression tests

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Acta Mechanica Sinica 2024年第8期40卷 179-193页

作者： Qiuxin Gu Qiang zhang yapeng Li Peinan Wu Guilei Han State Key Laboratory for Geomechanics and Deep Underground Engineering School of Mechanics and Civil EngineeringChina University of Mining and TechnologyXuzhou221116China North China Engineering Investigation Institute Shijiazhuang050021China

The recoverable strain of rock is completely classified as elastic strain in the conventional elastic-plastic theory,which often results in poor agreement between theoretical and experimental *** work proposes an improved elastoplastic model of rock materials considering the evolutions of crack deformation and elastic modulus to better characterize the nonlinear mechanical behavior of rock in the post-peak *** this model,the recoverable strain is assumed to be a combination of elastic and crack strain,and the constitutive relationship between crack strain and rock stress is *** on the proposed assumption,the evolutions of the mechanical parameters including strength parameters,elastic,plastic,and crack deformation parameters versus the plastic strain and confining stress were *** developed elastoplastic model was validated by comparing the theoretical values with the results of the triaxial cyclic loading and unloading *** theoretical calculation results show a good agreement with the laboratory test,which indicates that the improved elastoplastic model can effectively reflect the nonlinear mechanical behavior of the rock *** research results are expected to provide a valuable reference for further understanding the evolution of rock crack deformation.

关键词： Crack strain Elastic modulus deterioration Novel elastoplastic model Model validation

Influences of lauric acid addition on performance,nutrient digestibility and proteins related to mammary gland development in dairy cows

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Animal Nutrition 2024年第3期18卷 272-283页

作者： Jing zhang Lijun Bu yapeng Liu Wenjie Huo Chengqiang Xia Caixia Pei Qiang Liu College of Animal Science Shanxi Agricultural UniversityTaigu 030801Shanxi ProvinceChina

Lauric acid(LA)has the possibility to improve milk production in dairy cows by improving mammary gland development,however,the mechanism by which it might regulate mammary gland development is *** influence of LA on milk production,nutrient digestibility and the expression of proteins related to mammary gland development in dairy cows were *** primiparous Holstein dairy cows were divided into 4 groups in a randomized block *** treatments included the control(0 g/d LA per cow),low-LA(100 g/d LA per cow),medium-LA(200 g/d LA per cow),and high-LA(300 g/d LA per cow).Yields of milk,fat-corrected milk,and energy-corrected milk quadratically increased(P<0.05),and yield and content of milk fat linearly increased(P<0.05)with LA *** of C12:0,C18:1 and C20:1 fatty acids in milk fat linearly increased(P<0.05),but that of C16:0 fatty acid linearly decreased(P=0.046).Supplementation of LA led to a linear and quadratical increase(P<0.05)in digestibility of dry matter,organic matter,neutral detergent fibre and acid detergent fibre,and ruminal total volatile fatty acid concentration but a linear reduction(P=0.018)in the ratio of acetate to *** enzymatic activities of ruminal pectinase,xylanase,andα-amylase,and populations of total bacteria and anaerobic fungi increased linearly(P<0.05),while populations of total protozoa and methanogens decreased linearly(P<0.05)with increased LA *** LA addition,blood glucose,triglyceride,estradiol,prolactin,and insulin-like growth factor 1 concentrations increased linearly(P<0.05)and albumin and total protein concentrations increased quadratically(P<0.05).Moreover,addition of 200 g/d LA promoted(P<0.05)the expression of protein involved in mammary gland development and fatty acids *** results suggested that LA addition enhanced milk production and fatty acids synthesis by stimulating nutrient digestion,the expression of proteins associated with milk fat synth

关键词： Lactation performance Lauric acid Mammary gland development Milk fat synthesis Nutrient digestibility

Durable K-ion batteries with 100% capacity retention up to 40,000 cycles

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Carbon Energy 2024年第5期6卷 201-212页

作者： Xianlu Lu Zhao Liang Zhi Fang Dongdong zhang yapeng Zheng Qiao Liu Dingfa Fu Jie Teng Weiyou Yang Institute of Micro/Nano Materials and Devices Ningbo University of TechnologyNingboZhejiangChina College of Materials Science and Engineering Hunan UniversityChangshaChina College of Mechanical and Vehicle Engineering Hunan UniversityChangshaChina

Currently,the major challenge in terms of research on K-ion batteries is to ensure that they possess satisfactory cycle stability and specific capacity,especially in terms of the intrinsically sluggish kinetics induced by the large radius of K+***,we explore high-performance K-ion half/full batteries with high rate capability,high specific capacity,and extremely durable cycle stability based on carbon nanosheets with tailored N dopants,which can alleviate the change of volume,increase electronic conductivity,and enhance the K+ion *** as-assembled K-ion half-batteries show an excellent rate capability of 468 mA h g^(−1) at 100 mA g^(−1),which is superior to those of most carbon materials reported to ***,the as-assembled half-cells have an outstanding life span,running 40,000 cycles over 8 months with a specific capacity retention of 100%at a high current density of 2000 mA g^(−1),and the target full cells deliver a high reversible specific capacity of 146 mA h g^(−1) after 2000 cycles over 2 months,with a specific capacity retention of 113%at a high current density of 500 mA g^(−1),both of which are state of the art in the field of K-ion *** study might provide some insights into and potential avenues for exploration of advanced K-ion batteries with durable stability for practical applications.

关键词： carbon nanosheet cycle stability K-ion batteries rate performance specific capacity

Neural Network Robust Control Based on Computed Torque for Lower Limb Exoskeleton

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 83-99页

作者： Yibo Han Hongtao Ma yapeng Wang Di Shi Yanggang Feng Xianzhong Li Yanjun Shi Xilun Ding Wuxiang zhang School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China Beihang Goer(WeiFang)Intelligent Robot Co. Ltd.Beihang UniversityWeifangChina Research Center of Satellite Technology Harbin Institute of TechnologyHarbinChina Beijing Xinfeng Aerospace Equipment Co. LtdBeijingChina

The lower limb exoskeletons are used to assist wearers in various scenarios such as medical and industrial *** modeling errors of the exoskeleton in different application scenarios pose challenges to the robustness and stability of its control *** Radial Basis Function(RBF)neural network is used widely to compensate for modeling *** order to solve the problem that the current RBF neural network controllers cannot guarantee the asymptotic stability,a neural network robust control algorithm based on computed torque method is proposed in this paper,focusing on trajectory *** innovatively incorporates the robust adaptive term while introducing the RBF neural network term,improving the compensation ability for modeling *** stability of the algorithm is proved by Lyapunov method,and the effectiveness of the robust adaptive term is verified by the *** wearing the exoskeleton under different walking speeds and scenarios were carried out,and the results show that the absolute value of tracking errors of the hip and knee joints of the exoskeleton are consistently less than 1.5°and 2.5°,*** proposed control algorithm effectively compensates for modeling errors and exhibits high robustness.

关键词： Lower limb exoskeleton Model compensation RBF neural network Computed torque method

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The First Global Map of Atmospheric Ammonia(NH_(3)) as Observed by the HIRAS/FY-3D Satellite

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Advances in Atmospheric Sciences 2024年第3期41卷 379-390页

作者： Minqiang ZHOU Zhili DENG Charles ROBERT Xingying zhang Lu zhang yapeng WANG Chengli QI Pucai WANG Martine De MAZIÈRE Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China Royal Belgian Institute for Space Aeronomy(BIRA-IASB) Brussels 1180Belgium National Satellite Meteorology Center China Meteorological AdministrationBeijing 100081China Department of Science&Technology and Climate Change China Meteorological AdministrationBeijing 100081China University of Chinese Academy of Sciences Beijing 100049China

Atmospheric ammonia(NH_(3)) is a chemically active trace gas that plays an important role in the atmospheric environment and climate change. Satellite remote sensing is a powerful technique to monitor NH_(3) concentration based on the absorption lines of NH_(3) in the thermal infrared region. In this study, we establish a retrieval algorithm to derive the NH_(3)column from the Hyperspectral Infrared Atmospheric Sounder(HIRAS) onboard the Chinese Feng Yun(FY)-3D satellite and present the first atmospheric NH_(3) column global map observed by the HIRAS instrument. The HIRAS observations can well capture NH_(3) hotspots around the world, e.g., India, West Africa, and East China, where large NH_(3) emissions exist. The HIRAS NH_(3) columns are also compared to the space-based Infrared Atmospheric Sounding Interferometer(IASI)measurements, and we find that the two instruments observe a consistent NH_(3) global distribution, with correlation coefficient(R) values of 0.28–0.73. Finally, some remaining issues about the HIRAS NH_(3) retrieval are discussed.

关键词： ammonia HIRAS/FY-3D satellite thermal-infrared observation remote sensing optimal estimation method

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