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4th IAHR Asian Working Group Symposium on Hydraulic Machinery and Systems

作者： Liu, J.T. Long, J. Chen, L. Qu, Z. Yao, C. Ye, W.X. Beijing Engineering Research Center of Efficient and Green Aerospace Propulsion Technology Beijing Institute of Control Engineering Beijing100190 China

A drop tower test system for microgravity experiment was established to analyze the performance of a propellant management device (PMD) with vertical vanes. The microgravity level was 10-3 g. Different volume fractions of liquid and different gravity directions were used to study the performance of the PMD. The changes in the gas-liquid interface were studied during the test. It was shown that the vane-type tank is suitable for reverse maneuvering process when volume fraction of propellant is more than 5%, and the propellant relocation time from high gravity condition to microgravity is less than 1.6 s. The inertia force weakens rapidly and the surface tension gradually plays a dominant role at the initial short time period (t © 2024 Institute of Physics Publishing. All rights reserved.

关键词： Propellants

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Fixed-Time Sliding Mode Fault-Tolerant Consensus control for Second-Order Multi-Agent System with Actuator Fault 41

Fixed-Time Sliding Mode Fault-Tolerant Consensus Control for...

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第41届中国控制会议

作者： Jing Wang Yi-ming Fang Jian-xiong Li Kun-da Li Key Lab of Industrial Computer Control Engineering of Hebei Province Yanshan University Engineering Research Center of the Ministry of Education for Intelligent Control System and Intelligent Equipment

ISBN: (数字)9789887581536

ISBN: (纸本)9781665482561

Aiming at the problems of immeasurable leader state and actuator fault for second-order multi-agent system(MAS),the distributed robust sliding mode fault-tolerant control method based on fixed-time state observer(FTSO) is adopted to realize the fixed time fault-tolerant consensus tracking control for the *** MAS is under the undirected communication *** actuator fault is including partial loss of effectiveness(PLOE) fault and bias ***,a fixed time state observer is designed for each follower to obtain the state information of the ***,for followers with actuator faults,the distributed fixed-time robust sliding mode fault-tolerant controller is designed to realize fault-tolerant consensus tracking ***,the Lyapunov stability theorem is used to prove that the observation error and the consensus control error converge to zero in a ***,the effectiveness of the designed FTSO and fixed-time robust sliding mode fault-tolerant control algorithm is verified by numerical simulation.

关键词： fixed-time state observer fixed-time fault-tolerant control multi-agent systems consensus tracking control

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Modelling medium-and long-term purchasing plans for environment-orientated container trucks:a case study of Yangtze River port

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Transportation Safety and Environment 2023年第1期5卷 66-75页

作者： Shuai Li Weijia Wu Xiaofeng Ma Ming Zhong Muhammad Safdar Intelligent Transportation Systems Center Wuhan University of TechnologyWuhan 430063HubeiChina National Engineering Research Center for Water Transport Safety Wuhan 430063HubeiChina.

The transportation sector is the most significant contributor to anthropogenic greenhouse gas(GHG)***,maritime transportation,which is predominantly powered by fossil-fuel engines,accounts for more than 90%of world freight movement and emits 3%of global carbon dioxide(CO_(2))*** is the world’s largest emitter of CO_(2 )and plays a key role in mitigating global climate *** order to tackle this pressing concern,this study analyses the port’s throughput,the current number of trucks and their emissions during the container truck purchasing *** studies about container truck purchasing plans mostly focused on the trucks’price and port *** objective of this study is to minimize the total cost of a port’s inland transportation using optimization technique such as the interval uncertainty planning model to convert container truck emissions into social *** study considers the port of Yangtze as a case *** study has designed two scenarios.(i)The base scenario(business-asusual,BAU)is used to quantify the relationship between pollutant emissions and system *** the base scenario,no environmental control facilities are used during the planning period,and there is no need to purchase new energy container trucks.(ii)The expected scenario(Scenario A)is for three planning *** Scenario A,the emissions levels are required to remain at the same level as the first planning period during the whole planning *** solving the above model,the number of all truck types,system cost,container throughput and truck emissions in the port area were *** results showed that if no emission reduction control measures are implemented in the next 9 years,the growth rate of pollutants in the port area could reach 20%.In addition,the findings showed clearly that truck emissions are reduced by purchasing new energy trucks and restricting the number of fossil-fuel(diesel)*** study could also help to minimize sy

关键词： container truck truck emissions optimization model interval uncertainty planning model Yangtze River port

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Near-field radiative heat transfer between nanoporous GaN films

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Chinese Physics B 2024年第4期33卷 109-120页

作者：韩晓政张纪红刘皓佗吴小虎冷惠文 School of Electromechanical and Automotive Engineering Yantai UniversityYantai 264005China Key Laboratory of Advanced Manufacturing and Intelligent Technology Ministry of EducationHarbin University of Science and TechnologyHarbin 150080China Thermal Science Research Center Shandong Institute of Advanced TechnologyJinan 250100China

Photon tunneling effects give rise to surface waves,amplifying radiative heat transfer in the near-field *** research has highlighted that the introduction of nanopores into materials creates additional pathways for heat transfer,leading to a substantial enhancement of near-field radiative heat transfer(NFRHT).Being a direct bandgap semiconductor,GaN has high thermal conductivity and stable resistance at high temperatures,and holds significant potential for applications in optoelectronic ***,study of NFRHT between nanoporous GaN films is currently lacking,hence the physical mechanism for adding nanopores to GaN films remains to be discussed in the field of *** this work,we delve into the NFRHT of GaN nanoporous films in terms of gap distance,GaN film thickness and the vacuum filling *** results demonstrate a 27.2%increase in heat flux for a 10 nm gap when the nanoporous filling ratio is ***,the spectral heat flux exhibits redshift with increase in the vacuum filling *** be more precise,the peak of spectral heat flux moves fromω=1.31×10^(14)rad·s^(-1)toω=1.23×10^(14)rad·s^(-1)when the vacuum filling ratio changes from f=0.1 to f=0.5;this can be attributed to the excitation of surface phonon *** introduction of graphene into these configurations can highly enhance the NFRHT,and the spectral heat flux exhibits a blueshift with increase in the vacuum filling ratio,which can be explained by the excitation of surface plasmon *** findings offer theoretical insights that can guide the extensive utilization of porous structures in thermal control,management and thermal modulation.

关键词： near-field radiative heat transfer nanoporous GaN film surface phonon polaritons surface plasmon polaritons

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A fast calculation method for three-impulse contingency return trajectory during the near-moon phase based on differential algebra

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Chinese Journal of Aeronautics 2025年第4期38卷 286-304页

作者： Lin LU Haiyang LI Tianshan DONG Wanmeng ZHOU College of Aerospace Science and Technology National University of Defense TechnologyChangsha 410073China Hunan Key Laboratory of Intelligent Planning and Simulation for Aerospace Missions Changsha 410073China Beijing Institute of Spacecraft System Engineering Beijing 100094China China Astronaut Research and Training Center Beijing 100094China

Aimed at the demand of contingency return at any time during the near-moon phase in the manned lunar landing missions,a fast calculation method for three-impulse contingency return trajectories is ***,a three-impulse contingency return trajectory scheme is presented by combining the Lambert transfer and maneuver at the special ***,a calculation model of three-impulse contingency return trajectories is ***,fast calculation methods are proposed by adopting the high-order Taylor expansion of differential algebra in the twobody trajectory dynamics model and perturbed trajectory dynamics ***,the performance of the proposed methods is verified by numerical *** results indicate that the fast calculation method of two-body trajectory has higher calculation efficiency compared to the semi-analytical calculation method under a certain accuracy *** to its high efficiency,the characteristics of the three-impulse contingency return trajectories under different contingency scenarios are further analyzed *** findings can be used for the design of contingency return trajectories in future manned lunar landing missions.

关键词： Manned lunar landing Contingency return trajectory Trajectory calculation method Differential algebra Trajectory characteristic analysis

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Spontaneous Recovery in Directed Dynamical Networks

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engineering 2024年第6期37卷 208-214页

作者： Xueming Liu Xian Yan H.Eugene Stanley School of Artificial Intelligence and Automation&The MOE Engineering Research Center of Autonomous Intelligent Unmanned Systems&the Key Laboratory of Image Processing Huazhong University of Science and TechnologyWuhan 430074China Center for Polymer Studies Department of PhysicsBoston UniversityBostonMA 02215USA

Complex networked systems,which range from biological systems in the natural world to infrastructure systems in the human-made world,can exhibit spontaneous recovery after a failure;for example,a brain may spontaneously return to normal after a seizure,and traffic flow can become smooth again after a *** studies on the spontaneous recovery of dynamical networks have been limited to undirected ***,most real-world networks are *** fill this gap,we build a model in which nodes may alternately fail and recover,and we develop a theoretical tool to analyze the recovery properties of directed dynamical *** find that the tool can accurately predict the final fraction of active nodes,and the prediction accuracy decreases as the fraction of bidirectional links in the network increases,which emphasizes the importance of directionality in network *** to different initial states,directed dynamical networks may show alternative stable states under the same control parameter,exhibiting hysteresis *** addition,for networks with finite sizes,the fraction of active nodes may jump back and forth between high and low states,mimicking repetitive failure-recovery *** findings could help clarify the system recovery mechanism and enable better design of networked systems with high resilience.

关键词： Network resilience Directed dynamical networks Spontaneous recovery

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MEMS and MOEMS Gyroscopes: A Review

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Photonic Sensors 2023年第4期13卷 73-98页

作者： Wenyi HUANG Xing YAN Sengyu ZHANG Zhe LI Jamal NAHASSAN Dingwei CHEN Guangjun WEN Kai CHEN Guangwei DENG Yongjun HUANG School of Information and Communication Engineering Sichuan Provincial Engineering Research Center of Communication Technology for Intelligent IoTUniversity of Electronic Science and Technology of ChinaChengdu 611731China School of Automation Engineering University of Electronic Science and Technology of ChinaChengdu 611731China Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu 610054China

Micro-gyroscopes using micro-electro-mechanical system(MEMS)and micro-optoelectro-mechanical system(MOEMS)are the new-generation and recently well-developed gyroscopes produced by the combinations of the traditional gyroscope technology and MEMS/MOEMS *** to the working principle and used materials,the newly-reported micro-gyroscopes in recent years include the silicon-based micromechanical vibratory gyroscope,hemispherical resonant gyroscope,piezoelectric vibratory gyroscope,suspended rotor gyroscope,microfluidic gyroscope,optical gyroscope,and atomic *** to different sensitive structures,the silicon-based micromechanical vibratory gyroscope can also be divided into double frame type,tuning fork type,vibrating ring type,and nested ring *** those micro-gyroscopes,in recent years,many emerging techniques are proposed and developed to enhance different aspects of performances,such as the sensitivity,angle random walk(ARW),bias instability(BI),and ***,this paper will firstly review the main performances and applications of those newly-developed MEMS/MOEMS gyroscopes,then comprehensively summarize and analyze the latest research progress of the micro-gyroscopes mentioned above,and finally discuss the future development trends of MEMS/MOEMS gyroscopes.

关键词： Micro-gyroscope MEMS MOEMS angular random walk bias instability

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PI-funnel and inverse hysteresis compensation cascade control of smart soft dielectric elastomer actuator

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control Theory and technology 2024年第4期22卷 552-567页

作者： Peng Huang Yawu Wang Yue Zhang Jundong Wu Chun-Yi Su School of Automation China University of GeosciencesWuhan430074HubeiChina Hubei Key Laboratory of Advanced Control and Intelligent Automation for Complex Systems Wuhan430074HubeiChina Engineering Research Center of Intelligent Technology for Geo-Exploration Ministry of EducationWuhan430074HubeiChina Gina Cody School of Engineering and Computer Science Concordia UniversityMontrealQCH3G 1M8Canada

Smart soft dielectric elastomer actuators(SSDEAs)possess wide applications in soft robotics due to their properties similar to natural muscles,including large deformation ratio,high energy density,and fast response ***,the complicated asymmetric and rate-dependent hysteresis property,creep property and quadratic input property of the SSDEA pose enormous challenges to its dynamic modeling and motion *** this paper,first,we construct the dynamic model of the SSDEA by connecting a square module,a one-sided Prandtl–Ishlinskii(OSPI)model and a linear system in series to describe the above *** key and innovative aspect of the dynamic modeling lies in cascading the square module in series with the OSPI model to construct the asymmetric hysteresis ***,a PI-funnel and inverse hysteresis compensation(PIFIHC)cascade control method of the SSDEA is proposed to actualize its tracking control *** performing the inversion operation on the asymmetric hysteresis model,the inverse hysteresis compensation controller(IHCC)is designed to compensate the asymmetric hysteresis property and quadratic input property of the *** addition,a PI-funnel controller is designed to cascade with the IHCC to construct the PIFIHC cascade controller to obtain a good tracking ***,the stability analysis of the PIFIHC cascade control system of the SSDEA is performed to theoretically prove that the tracking error can be controlled within the performance funnel and the steady-state error converges to ***,several practical tracking control experiments of the SSDEA are conducted,and RRMSEs are less than 2.30%for all *** experimental results indicate the effectiveness and feasibility of the proposed PIFIHC cascade control method of the SSDEA.

关键词： Smart soft dielectric elastomer actuator Dynamic modeling Inverse hysteresis compensation controller PI-funnel controller Cascade controller

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Unveiling the Investigation and Comfort research in Various Scenarios of Mask Protection Equipment against Respiratory Transmission

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American Journal of Biochemistry and Biotechnology 2024年第1期20卷 7-15页

作者： Zhang, Xin Hebei Key Laboratory of Man-Machine Environment Thermal Control Technology and Equipment Hebei China Advanced Research Center of Thermal and New Energy Technologies Hebei Vocational University of Technology and Engineering Hebei China

Personal Protective Equipment (PPE) is essential to protect medical staff (HCW) from highly infectious diseases such as COVID-19 and masks are indeed important functional small effective defensive equipment in safeguarding the public from infection. However, the thermal comfort, fit, and difficulty breathing when wearing a mask can affect its use and improve filtration efficiency. In addition, there is a lack of available research on thermal comfort, fit, and respiration of masks under actual wearing conditions. To this end, a questionnaire survey and thermal comfort evaluation were used to investigate the thermal comfort and breathing difficulties of 75 volunteers wearing masks in Beijing, Tianjin, and Hebei. The results show that the main types of masks in various scenarios are medical masks. Except for the outdoors, the proportion of people who feel basic comfort and fit is the highest in these four areas. About a quarter of people experienced an average of 50-60 and 20-30 min of breathing difficulties in winter and summer, respectively. This study provides a systematic analysis and useful data for mask design and the development of human public health. © 2024 Xin Zhang.

关键词： Diseases

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Gait Learning Reproduction for Quadruped Robots Based on Experience Evolution Proximal Policy Optimization

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Journal of Shanghai Jiaotong University (Science) 2023年 1-9页

作者： Li, Chunyang Zhu, Xiaoqing Ruan, Xiaogang Liu, Xinyuan Zhang, Siyuan Faculty of Information Technology Beijing University of TechnologyBeijing Key Laboratory of Computational Intelligence and Intelligent SystemEngineering Research Center of Digital Community of Ministry of Education Beijing100124 China

Bionic gait learning of quadruped robots based on reinforcement learning has become a hot research topic. The proximal policy optimization (PPO) algorithm has a low probability of learning a successful gait from scratch due to problems such as reward sparsity. To solve the problem, we propose a experience evolution proximal policy optimization (EEPPO) algorithm which integrates PPO with priori knowledge highlighting by evolutionary strategy. We use the successful trained samples as priori knowledge to guide the learning direction in order to increase the success probability of the learning algorithm. To verify the effectiveness of the proposed EEPPO algorithm, we have conducted simulation experiments of the quadruped robot gait learning task on Pybullet. Experimental results show that the central pattern generator based radial basis function (CPG-RBF) network and the policy network are simultaneously updated to achieve the quadruped robot’s bionic diagonal trot gait learning task using key information such as the robot’s speed, posture and joints information. Experimental comparison results with the traditional soft actor-critic (SAC) algorithm validate the superiority of the proposed EEPPO algorithm, which can learn a more stable diagonal trot gait in flat terrain. © 2023, Shanghai Jiao Tong University.

关键词： Bionics

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