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The Intelligent Properties of Micro-reactors for Preparating Nanoparticles

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Chinese Chemical Letters 2003年第8期14卷 877-880页

作者： Gang WEI Hai Yan HUANG rong Chun xiong College of Materials Science and Engineering Beijing University of Chemical TechnologyBeijing 100029

TiO2 nanoparticles were synthesized by using micro-reactors. The shape and size of the nanoparticles produced from the original micro-reactors and the five times recycled micro-reactors mother liquor were investigated on transmission electron microscopy (TEM) by using the original sample, freeze prepared sample, and dyeing treated sample, respectively. UV-VIS spectrometry was used to study the growth process of TiO2 nanoparticles in main reactors. The results showed that micro-reactors with nanometer magnitude had spherical or oval structures, and could restore to their original structure after they were destroyed. The products prepared in the original micro-reactors were similar to that in the micro-reactors recycled for many times, suggesting that the micro-reactors had memory function.

关键词： Micro-reactors nanoparticles titanium dioxide intelligent properties.

Preparation and Characterization of Nano-Structured SiO_(2) Thin Films on Carbon Steel

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Chinese Chemical Letters 2003年第11期14卷 1167-1170页

作者： rong Chun xiong Dong Zhou YAN Gang WEI College of Material Science and Engineering Beijing University of Chemical TechnologyBeijing 100029

Nano-structured SiO2 thin films were prepared on the surface of carbon steel for the first time by LPD. The compositions of the films were analyzed by XPS, and the surface morphology of the thin films were observed by AFM. The thin films were constituted by compact particles of SiO2, and there was no Fe in the films. In the process of film forming, the SiO2 colloid particles were deposited or absorbed directly onto the surface of carbon steel substrates that were activated by acid solution containing inhibitor, and corrosion of the substrates was avoided. The nano-structured SiO2 thin films that were prepared had excellent protective efficiency to the carbon steel.

关键词： Carbon steel sodium silicate nano-structured SiO_(2) thin films AFM.

A multi-class large margin classifier

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第2期10卷 253-262页

作者： Liang TANG Qi XUAN rong xiong Tie-jun WU Jian CHU Institute of Cyber-Systems and Control Zhejiang University Hangzhou 310027 China

Currently there are two approaches for a multi-class support vector classifier(SVC). One is to construct and combine several binary classifiers while the other is to directly consider all classes of data in one optimization formulation. For a K-class problem(K>2),the first approach has to construct at least K classifiers,and the second approach has to solve a much larger op-timization problem proportional to K by the algorithms developed so far. In this paper,following the second approach,we present a novel multi-class large margin classifier(MLMC). This new machine can solve K-class problems in one optimization formula-tion without increasing the size of the quadratic programming(QP) problem proportional to K. This property allows us to construct just one classifier with as few variables in the QP problem as possible to classify multi-class data,and we can gain the advantage of speed from it especially when K is large. Our experiments indicate that MLMC almost works as well as(sometimes better than) many other multi-class SVCs for some benchmark data classification problems,and obtains a reasonable performance in face recognition application on the AR face database.

关键词： Multi-classification Support vector machine (SVM) Quadratic programming (QP) problem Large margin

The beaming effect and γ-ray emission for Fermi blazars

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Research in Astronomy and Astrophysics 2016年第1期16卷 107-116页

作者： Yong-Yun Chen xiong Zhang Ding-rong xiong Si-Ju Wang Xiao-Ling Yu Department of Physics Yunnan Normal University Kunming 650500 China Yunnan Observatories Chinese Academy of Sciences Kunming 650011 China Dongxing Middle School Chuxiong 675000 China

We study the γ-ray luminosity and beaming effect for Fermi *** results are as follows.（i） There are significant correlations between γ-ray luminosity and radio core luminosity,and between γ-ray luminosity and R_v,which suggests that the γ-ray emissions have a strong beaming effect,（ⅱ） Using the L_（ext）/M_（abs） as an indicator of environment effects,we find that there is no significant correlation betweenγ-ray luminosity and L_（ext）/M_（abs） for all sources when we remove the effect of *** spectrum radio quasars considered alone also do not show a significant correlation,but BL Lacertae objects（BL Lacs） still show a significant correlation when we remove the effect of *** results suggest that the γ-ray emission may be affected by the environment on a kiloparsec scale for BL Lacs.

关键词： BL Lacerate objects: general -- quasars: general -- gamma-rays: galaxies -- radio continuumgalaxies

Untethered quadrupedal hopping and bounding on a trampoline

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Frontiers of Mechanical Engineering 2020年第2期15卷 181-192页

作者： Boxing WANG Chunlin ZHOU Ziheng DUAN Qichao ZHU Jun WU rong xiong State Key Laboratory of Industrial Control Technology College of Control Science and EngineeringZhejiang UniversityHangzhou 310027China Binhai Industrial Technology Research Institute of Zhejiang University Tianjin 300301China

For quadruped robots with springy legs,a successful jump usually requires both suitable elastic parts and well-designed control ***,these two problems are mutually restricted and hard to solve at the same *** this study,we attempt to solve the problem of controller design with the help of a robot without any elastic mounted parts,in which the untethered robot is made to jump on a *** differences between jumping on hard surfaces with springy legs and jumping on springy surfaces with rigid legs are briefly *** intuitive control law is proposed to balance foot contact forces;in this manner,excessive pitch oscillation during hopping or bounding can be *** height is controlled by tuning the time delay of the leg *** with other motion generators based on kinematic law,the robot can perform translational and rotational movements while hopping or bounding on the *** are conducted to validate the effectiveness of the proposed control framework.

关键词： hopping and bounding gait compliant mechanism compliant contact balance control strategy legged locomotion control quadruped robot

A hybrid visual servo control method for simultaneously controlling a nonholonomic mobile and a manipulator

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Frontiers of Information Technology & Electronic Engineering 2021年第2期22卷 141-154页

作者： Wei LI rong xiong State Key Laboratory of Industrial Control Technology Zhejiang UniversityHangzhou 310027China

Visual servo control rules that refer to the control methods of robot motion planning using image data acquired from the camera mounted on the robot have been widely applied to the motion control of robotic arms or mobile *** methods are usually classified as image-based visual servo,position-based visual servo,and hybrid visual servo(HVS)control *** manipulation enhances the working range and flexibility of robotic ***,there is little work on applying visual servo control rules to the motion of the whole mobile manipulation *** propose an HVS motion control method for a mobile manipulation robot which combines a six-degreeof-freedom(6-DOF)robotic arm with a nonholonomic mobile *** on the kinematic differential equations of the mobile manipulation robot,the global Jacobian matrix of the whole robot is derived,and the HVS control equation is derived using the whole Jacobian matrix combined with position and visual image *** distance between the gripper and target is calculated through the observation of the marker by a camera mounted on the *** differences between the positions of the markers’feature points and the expected positions of them in the image coordinate system are also *** differences are substituted into the control equation to obtain the speed control law of each degree of freedom of the mobile manipulation *** avoid the position error caused by observation,we also introduce the Kalman filter to correct the positions and orientations of the end of the ***,the proposed algorithm is validated on a mobile manipulation platform consisting of a Bulldog chassis,a UR5 robotic arm,and a ZED camera.

关键词： Mobile manipulation Hybrid visual servo Eye-in-hand Global Jacobian Kalman filter

Multicolor Optical Monitoring of the γ-Ray Emitting Narrow-line Seyfert 1 Galaxy PMN J0948+0022 from 2020 to 2021

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Research in Astronomy and Astrophysics 2022年第7期22卷 60-72页

作者： Yu-Xin Xin Ding-rong xiong Jin-Ming Bai Hong-Tao Liu Kai-Xing Lu Ji-rong Mao Yunnan Observatories Chinese Academy of SciencesKunming 650216China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China Center for Astronomical Mega-Science Chinese Academy of SciencesBeijing 100101China

In order to study the physical properties of the γ-ray emitting narrow-line Seyfert 1(NLS1) galaxy population,photometric and spectral observations of the γ-ray emitting NLS1 PMN J0948+0022 were made with the Lijiang2.4 m optical telescope of Yunnan Observatories,Chinese Academy of *** data in the B and R bands were collected for 50 nights from 2020 January to 2021 *** the observation epoch,the variability amplitudes are 73.67% in the B band and 79.96% in the R ***-day variability is found in two observation nights,and the duty cycle value is 29% with variability amplitude> 12.9% in the R band,which support the presence of the relativistic jets in the *** redder-when-brighter(RWB) chromatic trend(or steeper-when-brighter trend) appears on intra-day and long *** RWB trend is dominated by the radiation of accretion disk and jet,and resembles those in flat spectrum radio *** PMN J0948+0022 is brighter than 17.5 in the R band,there is no color change *** analyzing the spectral data of PMN J0948+0022,we obtained the black hole mass of M.=1.61×10^(7) Mand accretion rate of M=93,and confirmed that PMN J0948+0022 is a super-Eddington accreting *** redshifts of reverberation mapped super-Eddington accreting active galactic nuclei can be expanded by PMN J0948+0022 up to above ***-Eddington accreting NLS1 galaxies were chosen as a new type of cosmological candle in the *** J0948+0022 may be used as a target for the next step of reverberation mapping monitoring project of super-Eddington accreting massive black holes.

关键词： galaxies:jets galaxies:photometry galaxies:Seyfert galaxies:active

A ZMP and CoM Online Replanning Method for Stable Walking of Bipedal Robots

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A ZMP and CoM Online Replanning Method for Stable Walking of...

A new nine-membdered lactone from a marine fungus Cladosporium sp.F14

第25届中国控制与决策会议

作者： Jianbo Zhan rong xiong Yichao Sun State Key Lab. of Industrial Control Technology Zhejiang University

ISBN: (纸本)9781467355339

Recent developed humanoid robots have had the capability to demonstrate fast and stable walking, while it is still a challenge for those robots to walk stably and flexibly in complex environments. A common solution is to search for appropriate footsteps either from a predefined motion set or not. However, the inaccuracy in models and external perturbation during implementation will make the robot fail to follow such footsteps. This paper proposes a solution to replan motions online, which promises the robot closely follow the given footsteps as well as keep stable. With analysis of the dynamics and kinematics of the humanoid robot, the proposed method replans the desired ZMP （Zero Moment Point） for the preview control based stable biped walking by combining the analysis on CoM （Center of Mass） state transition and the adjustment of supporting time. Then the desired ZMP is slightly regulated within its stable region to achieve a smooth CoM trajectory. Through the dynamic planning process in each control cycle, the robot can perform flexible motions with balance maintained. The simulation results indicate that the method proposed can effectively overcome external disturbances and provide better support during biped walking. The time cost also meets demands of online control.

关键词： Biped Motion CoM Planning ZMP Planning

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Chinese Chemical Letters 2010年第11期21卷 1355-1357页

作者： Cheng Hai Gao Xu Hua Nong Shu Hua Qi xiong Ming Luo Si Zhang Hai rong xiong Key Laboratory of Marine Bio-resources Sustainable Utilization/Research Center for Marine Microbes/ Guangdong Key Laboratory of Marine Materia Medica South China Sea Institute of Oceanology The Chinese Academy of Sciences Guangzhou 510301 China Graduate School of the Chinese Academy of Sciences Beijing 100049 China Life Science College South-Central University for Nationalities Wuhan 430074 China

A new nine-membered lactone,cladospolide E（1）,was isolated from a culture broth of a marine fungus Cladosporium sp.F14. The structure of compound 1 was determined on the basis of extensive spectroscopic analysis,inc... 详细信息

关键词： Cladosporium sp Marine fungus Nine-membered lactone Cladospolide E