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The research on direct-drive wave energy conversion system and performance optimization

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Acta Oceanologica Sinica 2014年第9期33卷 178-183页

作者： CHEN Zhongxian YU Haitao HU Minqiang Engineering Research Center of motion Control of Ministry of Education Southeast University

A direct-drive wave energy conversion system based on a three-phase permanent magnet tubular linear generator （PMTLG） and a heaving buoy is proposed to convert wave energy into electrical energy. Sufficient experimental methods are adopted to compare the computer simulations, the validity of which is verified by the experiment results from a wave tank laboratory. In the experiment, the motion curves of heaving buoy are with small fluctuations, mainly caused by the PMTLG＇s detent force. For the reduction of these small fluctuations and a maximum operational efficiency of the direct-drive wave energy conversion system, the PMTLG＇s detent force minimization technique and the heaving buoy optimization will be discussed. It is discovered that the operational efficiency of the direct-drive wave energy conversion system increases dramatically after optimization. The experiment and optimization results will provide useful reference for the future research on ocean wave energy conversion system.

关键词： wave energy conversion linear generator detent force minimization technique heaving buoy optimization

The Phenomena of Bifurcation and Catastrophe of Large-Scale Horizontal motion in the Atmosphere under the Effect of Rossby Parameter

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Advances in Atmospheric Sciences 1990年第4期7卷 409-422页

作者：万军杨芳林 Chendu Meteorological Institute. Chendu 610041 Institute of Atmospheric Physics Academia SincaBeijinghe stability question of large-scale horizontal motion in the atmosphere under the effect of Rossby parameter is discussed in this paper by using the qualitative analysis theory of ordinary differential equations. The following aspects are reviewed: The stability of large-scale horizontal motion in the atmosphere accords with the common inertial stability criterion when the effect of Rossby parameter is not considered (Yang 1983) and that on the other hand the motion will bifurcate two times with the variation of absolute vorticity of basic Zephyr flow at the initial position under the effect of Rossby parameter. Furthermore in the inertial stable region if the effect of geostrophic deviation at the initial position is considered the motion will not only bifurcate but also generate a catastrophe.

The stability question of large-scale horizontal motion in the atmosphere under the effect of Rossby parameter is discussed in this paper by using the qualitative analysis theory of ordinary differential equations. The following aspects are reviewed: The stability of large-scale horizontal motion in the atmosphere accords with the common inertial stability criterion when the effect of Rossby parameter is not considered (Yang, 1983), and that, on the other hand, the motion will bifurcate two times with the variation of absolute vorticity of basic Zephyr flow at the initial position under the effect of Rossby parameter. Furthermore, in the inertial stable region, if the effect of geostrophic deviation at the initial position is considered, the motion will not only bifurcate but also generate a catastrophe.

关键词： The Phenomena of Bifurcation and Catastrophe of Large-Scale Horizontal motion in the Atmosphere under the Effect of Rossby Parameter

Real-time traffic information extraction based on compressed video with interframe motion vector

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Journal of Harbin Institute of Technology(New Series) 2003年第3期10卷 284-289页

作者：黄庆明王聪 Joint R&D Lab Graduate School Chinese Academy of Sciences Beijing 100080 China School of Astronautics Harbin Institute of Technology Harbin 150001 Chinaxtraction of traffic information from image or video sequence is a hot research topic in intelligent transportation system and computer vision. A real-time traffic information extraction method based on compressed video with interframe motion vectors for speed density and flow detection has been proposed for extraction of traffic information under fixed camera setting and well-defined environment. The motion vectors are first separated from the compressed video streams and then filtered to eliminate incorrect and noisy vectors using the well-defined environmental knowledge. By applying the projective transform and using the filtered motion vectors speed can be calculated from motion vector statistics density can be estimated using the motion vector occupancy and flow can be detected using the combination of speed and density. The embodiment of a prototype system for sky camera traffic monitoring using the MPEG video has been implemented and experimental results proved the effectiveness of the method proposed.

Extraction of traffic information from image or video sequence is a hot research topic in intelligenttransportation system and computer vision. A real-time traffic information extraction method based on com-pressed video with interframe motion vectors for speed, density and flow detection, has been proposed for ex-traction of traffic information under fixed camera setting and well-defined environment. The motion vectors arefirst separated from the compressed video streams, and then filtered to eliminate incorrect and noisy vectors u-sing the well-defined environmental knowledge. By applying the projective transform and using the filtered mo-tion vectors, speed can be calculated from motion vector statistics, density can be estimated using the motionvector occupancy, and flow can be detected using the combination of speed and density. The embodiment of aprototype system for sky camera traffic monitoring using the MPEG video has been implemented, and experi-mental results proved the effectiveness of the method proposed.

关键词： extraction of traffic information Interframe motion vector compressed video stream

Controller design based on viscoelasticity dynamics model and experiment for flexible drive unit

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Journal of Central South University 2014年第12期21卷 4468-4477页

作者：吴伟国侯月阳 Humanoid and Gorilla Robot & Its Intelligent motion Control Lab Harbin Institute of Technology

In order to ensure that the system has the advantage of light weight and vibration absorption, the steel rope is used as a flexible transmission part. A flexible drive unit(FDU) is developed, whose features are guided by steel rope, increasing force by the movable pulley group, modular, convenient and flexible. Dynamics model for controller is deduced based on the constitutive equation of viscoelasticity. Controller is designed for position control and is based on the viscoelasticity dynamics model compensation control strategy proposed. The control system is based on the TURBO PMAC multi-axis motion control *** loading experiments and velocity experiments results show that the FDU can reach 2 Hz with no load and the max speed of 30(°)/s. The FDU has the capability of the load torque 11.2 N·m and the speed of 24(°)/s simultaneously, and the frequency response is 1.3 Hz. The FDU can be used to be the pitch joint of hip for biped robot whose walking speed is 0.144 km/h theoretically.

关键词： flexible drive unit steel rope drive viscoelasticity dynamic model speed-load characteristic

Multi-Exposure motion Estimation Based on Deep Convolutional Networks

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Journal of Computer Science & Technology 2018年第3期33卷 487-501页

作者： Zhi-Feng Xie Yu-Chen Guo Shu-Han Zhang Wen-Jun Zhang Li-Zhuang Ma Department of Film and Television Engineering Shanghai University Shanghai 200072 China Shanghai Engineering Research Center of motion Picture Special Effects Shanghai 200072 China Department of Software Science and Technology East China Normal University Shanghai 200062 China

In motion estimation, illumination change is always a troublesome obstacle, which often causes severely per- formance reduction of optical flow computation. The essential reason is that most of estimation methods fail to formalize a unified definition in color or gradient domain for diverse environmental changes. In this paper, we propose a new solution based on deep convolutional networks to solve the key issue. Our idea is to train deep convolutional networks to represent the complex motion features under illumination change, and further predict the final optical flow fields. To this end, we construct a training dataset of multi-exposure image pairs by performing a series of non-linear adjustments in the traditional datasets of *** estimation. Our multi-exposure flow networks （MEFNet） model consists of three main components： low-level feature network, fusion feature network, and motion estimation network. The former two components belong to the contracting part of our model in order to extract and represent the multi-exposure motion features; the third component is the expanding part of our model in order to learn and predict the high-quality optical flow. Compared with many state- of-the-art methods, our motion estimation method can eliminate the obstacle of illumination change and yield optical flow results with competitive accuracy and time efficiency. Moreover, the good performance of our model is also demonstrated in some multi-exposure video applications, like HDR （high dynamic range） composition and flicker removal.

关键词： motion estimation optical flow convolutional neural network multi-exposure

The effect of fitness level on cardiac autonomic regulation, IL-6,total antioxidant capacity, and muscle damage responses to a single bout of high-intensity interval training

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Journal of Sport and Health Science 2018年第3期7卷 363-371页

作者： Lukas Cipryan Human motion Diagnostic Centre and Department of Human Movement Studies Ostrava University

Purpose:The aim of this study was to investigate the influence of the cardiorespiratory fitness level on the response to high-intensity interval training(HIIT)with an individually adjusted running speed of the same relative *** evaluation focused on acute cardiorespiratory response,postexercise cardiac autonomic modulation(heart rate variability(HRV))and biochemical markers of inflammation,oxidative stress,and muscle ***:Thirty participants were divided into 3 subgroups:well trained,moderately trained,and *** the participants performed30 min HIIT composed of 6×2 min interval exercise with work-to-relief ratio=1 and work intensity 100%of individual velocity at maximal oxygen consumption(VO2max).Acute cardiorespiratory variables,postexercise HRV,lactate,interleukin-6(IL-6),total antioxidant capacity(TAC),creatine kinase,and myoglobin up to 4h after HIIT were ***:The differences in relatively expressed cardiorespiratory variables(heart rate,VO2)during HIIT were at most moderate,with the most pronounced between-group differences in absolute VO2 *** disruption of the postexercise HRV was the most pronounced in untrained individuals,and this difference persisted 1 h after *** highest postexercise IL-6 and TAC concentrations and the lowest changes in creatine kinase and myoglobin were revealed in well-trained ***:The higher fitness level was associated with the less pronounced postexercise cardiac autonomic changes and their faster restoration,even when there were similar acute cardiorespiratory *** findings were simultaneously accompanied by the higher postexercise IL-6 and TAC concentrations and less significant changes in muscle damage biochemical markers in well-trained individuals.

关键词： Creatine kinase Heart rate variability Inflammation Myoglobin Total antioxidant capacity Training status

Research of 6-DOF Serial-Parallel Mechanism Platform for Stability Training of Legged-Walking Robot

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Journal of Harbin Institute of Technology(New Series) 2014年第2期21卷 75-82页

作者： Wei-Guo Wu Wen-Qian Du Humanoid and Gorilla Robot & Its Intelligent motion Control Lab Harbin Institute of Technology

The concept of legged-robot stability training with a training platform is proposed and a serial-parallel mechanism platform with 6 degrees of freedom is designed for this target. The designed platform is composed of 4-DOF parallel mechanism with spherical joints and prismatic pairs,and 2-DOF serial mechanism with prismatic pairs. With this design,the platform has advantages of low platform countertop,big workspace,high carrying capacity and high stiffness. On the basis of DOF analysis and computation of space mechanism,weight supporting auxiliary mechanism and raceways-balls supporting mechanism are designed,so as to improve the stiffness of designed large platform and payload capacity of servo motors. And then the whole structure design work of the platform is done. Meanwhile,this paper derives the analytical solutions of forward kinematics, inverse kinematics and inverse dynamics. The error analysis model of position and orientation is established. And then the simulation is done in ADAMS to ensure the correctness and feasibility of this design.

关键词： 6-DOF serial-parallel mechanism forward kinematics stability training legged-walking robot

ON THE STABILITY OF NON-AUTONOMOUS motion OF NON-LINEAR AUTOMATIC CONTROL SYSTEMS WITH TIME-LAGS

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Chinese Science Bulletin 1983年第1期28卷 10-15页

作者：斯力更 Inner Mongolia Teachers College Huhehot. K. Begelbahyev investigated problems of determination of stability limit for autonomous motion and non-autonomous motion of non-linear automatic control systems .

A. K. Begelbahyev investigated problems of determination of stability limit for autonomous motion and non-autonomous motion of non-linear automatic control systems; as well as problems of determination of stability limit for autonomous motion of non-linear automatic control systems with time-lags. Recently, the author used the method introduced in [4] to improve the results of [2].

关键词： autonomous 蛇山 satisfy notation perturbation differentiable furthermore 孟公 inequality roots

Could near infrared spectroscopy be the new weapon in our understanding of the cerebral and muscle microvascular oxygen demand during exercise?

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Journal of Sport and Health Science 2024年第4期13卷 457-458页

作者： Stephane Perrey EuroMov Digital Health in motion University of MontpellierIMT Mines AlesMontpellier 34090France

Near-infrared spectroscopy(NIRS)has been increasingly utilized in both sport and health sciences to assess various physiological parameters related to exercise performance.1 NIRS methods coupled with the recent development of portable and wearable devices suitable for field-based measurements have revolutionized the study of exercise physiology and the determinants of exercise performance by providing real-time,non-invasive,and spatially localized measurements of tissue oxygenation dynamics.

关键词： cerebral utilized exercise