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基于虚拟模型的四足机器人直觉控制

上海交通大学学报 2002年第8期36卷 1150-1154页

作者：陈佳品程君实席裕庚上海交通大学信息存储研究中心上海200030 上海交通大学自动化研究所

JTUWM- 四足机器人在关节上设置驱动器 ,高层的步行任务转化为低层关节空间的驱动控制 ,它是非直觉的 .针对这一问题 ,以虚拟驱动器模拟实际关节转矩 ,基于此虚拟驱动器的模型 ,将高层的步行任务转化为底层的关节转矩控制 ,凭直觉连续... 详细信息

JTUWM- 四足机器人在关节上设置驱动器 ,高层的步行任务转化为低层关节空间的驱动控制 ,它是非直觉的 .针对这一问题 ,以虚拟驱动器模拟实际关节转矩 ,基于此虚拟驱动器的模型 ,将高层的步行任务转化为底层的关节转矩控制 ,凭直觉连续设置虚拟力使机器人不断从平衡状态进入不平衡状态 ,进而由虚拟模型得到期望转矩。

关键词：四足步行机器人虚拟模型直觉控制虚拟构件驱动器关节转矩控制平衡状态

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四足机器人对角小跑直线步行的虚拟模型

上海交通大学学报 2001年第12期35卷 1771-1775页

作者：陈佳品程君实席裕庚上海交通大学信息存储研究中心上海200030 上海交通大学自动化研究所

提出用虚拟模型控制技术实现四足步行机器人的对角小跑直线步行 .在阐述虚拟模型概念的基础上 ,推导了 JTUWM- 四足机器人对角支撑和四足支撑的虚拟模型 ,实现了对角小跑步态 ,机体步行速度为 0 .2

关键词：四足步行机器人虚拟模型控制对角小跑虚拟力

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Mixed Dead-time Effect Suppression Strategy for Modular Multilevel Converters

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CSEE Journal of Power and Energy Systems 2024年第3期10卷 1075-1084页

作者： Zhi geng Minxiao Han School of Electrical and Electronic Engineering North China Electric Power UniversityBeijing 102206China IEEE

Dead time is necessary for the coupled power switches to prevent shoot-through,especially in the modular multilevel converters(MMCs)with a large number of power *** paper proposes a dead-time effect suppression strategy for MMCs with nearest level *** operational principles of MMCs are first *** to the operational features of MMCs,the method that removes a switching signal from the coupled switches and the reduced switching frequency voltage balancing algorithms(RSFVBAs)are mixed in the proposed *** the intervals that are furthest away from the zerocrossing points(ZCP)of arm currents,the single switching signal method can completely eliminate the dead-time effect(DTE).Alternatively,the DTE is suppressed by the RSFVBA in intervals that are close to the *** the combination of the two methods,the dependence of the DTE suppression method on currents is reduced and the influences of ZCP are also released without degrading the normal operation performance of ***,the output performance of MMCs is improved and the voltage stress on the arm inductor dramatically ***,the validation of the method is verified by the simulation results with the professional tool Matlab/Simulink.

关键词： Dead-time effect modular multilevel converters switching frequency voltage balancing algorithm

Investigation and measurement of old building response to the overlapped shield tunnel of multiple schemes in the sandy cobble stratum

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Underground Space 2024年第2期15卷 260-274页

作者： Xue Li Aopeng geng School of Geoscience and Technology Southwest Petroleum UniversityChengduSichuan 610500China China Railway Construction Bridge Engineering Bureau Group Co. Ltd.Tianjin 300300China

Ground movements due to tunneling are becoming increasingly critical as buildings are located around construction *** study proposes a new combined reinforcement method using a foundation grouting oblique pipe *** former improves the bearing capacity of the subsoil,and the latter blocks the transmission of soil deformation,which weakens the influence of construction during overlapped tunnel *** on this new method,a case study of the shield tunneling response to an old building in Line 6 of China’s Chengdu Metro is ***,three-dimensional numerical models without reinforcement,traditional foundation grouting reinforcement,and the new combined reinforcement schemes were *** numerical simulation performance was verified using a set of field instrumentation data,which demonstrated that the old building response to the overlapped tunnels was under control,and the maximum deformation,angular distortion,and principal tensile strain of the building were 5.25 mm,5.1.1.–6 rad/m,and 0.0081.,*** with the traditional reinforcement scheme,the deformation,angular distortion,and principal tensile strain in the combined reinforcement scheme were reduced by 54.78%,71.02%,and 70.22%,*** results have important implications for the design and construction of shield tunnels and their response to old buildings.

关键词： Overlapped tunnels Reinforcement schemes Under-crossing Old building Numerical simulation

Boosting electrocatalytic nitrate reduction to ammonia via Cu_(2)O/Cu(OH)_(2)heterostructures promoting electron transfer

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Nano Research 2024年第6期17卷 4898-4907页

作者： Jing geng Sihan Ji Anhui Province International Research Center on Advanced Building Materials School of Materials Science and Chemical EngineeringAnhui Jianzhu UniversityHefei 230601China Anhui Province Key Laboratory of Advanced Building Materials Anhui Jianzhu UniversityHefei 230601China School of Energy Materials and Chemical Engineering Hefei UniversityHefei 230601China

Electrocatalytic nitrate(NO_(3)^(−))reduction to ammonia(NH_(3))offers a viable approach for sustainable NH_(3)production and environmental ***(Cu)possesses a distinctive electronic structure,which can augment the reaction kinetics of NO_(3)^(−)and impede hydrogen evolution reaction(HER),rendering it a promising contender for the electrosynthesis of NH_(3)from NO_(3)^(−).Nevertheless,the role of Cu_(2)O in copper-based catalysts still requires further investigation for a more comprehensive ***,the Cu_(2)O/Cu(OH)_(2)heterostructures are successfully fabricated through liquid laser irradiation using CuO nanoparticles as a *** and theoretical researches reveal that Cu_(2)O/Cu(OH)_(2)heterostructure exhibits enhanced electrocatalytic performance for NO_(3)^(−)to NH_(3)because Cu(OH)_(2)promotes electron transfer and reduces the valence state of Cu active site in Cu_(2)***−0.6 V(*** hydrogen electrode(RHE)),the NH_(3)yield reaches its maximum at 1.30.66±29.72μg·h^(−1.·mgcat^(−1.,while the maximum of Faraday efficiency(FE)is 76.95%±5.51..This study expands the technical scope of copper-based catalyst preparation and enhances the understanding of the electrocatalytic mechanism of NO_(3)^(−)to NH_(3).

关键词： Cu_(2)O/Cu(OH)_(2)heterostructures electron transfer ammonia synthesis electrocatalysts nitrate

Structural engineered living materials

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Nano Research 2024年第2期17卷 715-733页

作者： Yang geng Zian Jia Ling Li 635 Prices Fork Road Department of Mechanical EngineeringVirginia Polytechnic Institute and State UniversityBlacksburg VA24061USA

Biological structural materials not only exhibit remarkable mechanical properties but also often embody dynamic characteristics such as environmental responsiveness,autonomy,and self-healing,which are difficult to achieve in conventional engineering *** merging materials science,synthetic biology,and other disciplines,engineered living materials(ELMs)provide a promising solution to combine living organisms with abiotic components,thus facilitating the construction of functional“living”*** natural materials,ELMs possess vitality and hold immense application potential in areas such as medicine,electronics,and construction,captivating increasing research attention *** an emerging branch of ELMs,structural ELMs aim to mimic living biological structural materials by achieving desired mechanical performance while maintaining important“living”*** we summarize the recent progress and provide our perspectives for this emerging research *** first summarize the superiority of structural ELMs by reviewing biological structural materials and biomimetic material design ***,we provide a systematic discussion on the definition and classifications of structural ELMs,their mechanical performance,and physiological ***,we summarize some critical challenges faced by structural ELMs and highlight directions of future *** hope this review article can provide a timely summary of the state of the art and relevant perspectives for future development of structural ELMs.

关键词： structural materials engineered living materials(ELMs) structural ELMs composites mechanical properties

Optimizing urban block morphologies for net-zero energy cities:Exploring photovoltaic potential and urban design prototype

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Building Simulation 2024年第4期17卷 607-624页

作者： Xiaotian geng Dong Xie Zhonghua Gou School of Urban Design Wuhan UniversityWuhanChina

The morphology of urban areas plays a crucial role in determining solar potential,which directly affects photovoltaic capacity and the achievement of net-zero *** study focuses on the City of Melbourne to investigate the utilization of solar energy across different urban densities and proposes optimized *** analysis encompasses blocks with diverse population densities,examining medium and high-density *** utilizing a multi-objective genetic optimization approach,the urban morphology of these blocks is *** findings indicate that low-density blocks exhibit photovoltaic potential ranging from 1.to 6.6 times their total energy *** and high-density blocks achieve photovoltaic potential levels approximately equivalent to 40%-85%of their overall energy ***,significant variations in photovoltaic potential are observed among different urban forms within medium and high-density ***“elevated corners with central valley”prototype is proposed as an effective approach,enhancing the overall photovoltaic potential by approximately 1.%.This study introduces novel analytical concepts,shedding light on the intricate relationship between urban morphologies and photovoltaic potential.

关键词： net-zero energy solar energy urban density urban morphology multi-objective optimization photovoltaic potential

Point defects in 2-D liquid crystals with a singular potential:Profiles and stability

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Science China Mathematics 2024年第11期67卷 2515-2540页

作者： Zhiyuan geng Wei Wang Basque Center for Applied Mathematics School of Mathematical Sciences Zhejiang University

We study radial symmetric point defects with degree k/2 in the 2-D disk or R2in the Q-tensor framework with a singular bulk energy,which is defined by Bingham ***,we obtain the existence of solutions for the profiles of radial symmetric point defects with degree k/2 in the 2-D disk or ***,we prove that the solution is stable for |k| = 1.and unstable for |k| > *** identities are derived and utilized throughout the proof of existence and stability/instability.

关键词： radial symmetric point defects singular bulk potential Bingham closure stability

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与鹅肥肝形成相关的血液生物标志物的筛选

中国家禽 2018年第15期40卷 11-15页

作者：邢娅刘龙赵超龚道清耿拓宇梁燕扬州大学动物科学与技术学院江苏扬州225009 江苏省苏北人民医院药学部江苏扬州225001

Micro RNAs(mi RNAs)通过作用于靶基因发挥其生物学功能。研究测定了填饲1. d的朗德鹅与对照组朗德鹅(非填饲的常规饲喂组)(每组3只)血清中的mi RNAs比较,筛选出对照组与填饲组存在显著差异的mi RNAs,并与肝脏中差异表达的mi RNAs比较,... 详细信息

Micro RNAs(mi RNAs)通过作用于靶基因发挥其生物学功能。研究测定了填饲1. d的朗德鹅与对照组朗德鹅(非填饲的常规饲喂组)(每组3只)血清中的mi RNAs比较,筛选出对照组与填饲组存在显著差异的mi RNAs,并与肝脏中差异表达的mi RNAs比较,确定在血液和肝脏中均共同上升的mi RNAs。结果表明:填饲朗德鹅血液中有295个mi RNAs的含量显著不同于对照组(1.个上升,276个下降),其中4个mi RNAs(let-7a-2-3p、mi R-1.4、mi R-222a-3p、mi R-1.62)在血液和肝脏中的含量均显著上升,提示它们可能是鹅肥肝形成的血液生物标志物。

关键词：鹅脂肪肝 microRNA 生物标物

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