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Design of an Automatic Autonomous Mini Prone-cone Microsatellite Docking Mechanism

Chinese Journal of Mechanical Engineering 2010年第3期23卷 353-360页

作者： LAI Yinan dai ye TIAN Hao ZHANG Dawei School of Mechanical and Power Engineering Harbin University of Science and Technology Harbin 150080 China Department of Astronautics andMechanics Harbin Institute of Technology Harbin 150001 China

The capability of docking, refueling, repairing, and updating microsatellites using automatic autonomous vehicles will be of significance critical value for design and operation of several space systems in the near feature. Automatic docking capability was successfully tested by many institutions such as National Space Development Agency in Japan, European Space Agency, National Aeronautics and Space Administration in USA, etc. However, there is still much more space for improvement of degree of automation during the process of docking with large deviations of the initial attitude. A novel automatic autonomous probe-cone docking mechanism used for microsatellite docking is proposed. This docking mechanism is designed according to the design indices such as miniaturization, degree of automation and automatic capture capability within large deviation of the initial attitude. On the basis of the virtual work principle, the dynamics modeling of the docking process is presented. The position of the contact point is then analyzed. Comprehensive system level simulation is conducted in the 13 kinds of typical operating conditions with the initial deviations. Capture performance is analyzed. The simulation results show that the docking mechanism can be smoothly captured within 2 s in all cases of large attitude deviation between the active and passive spacecrafts. A virtual prototype model of the docking mechanism is established through ADAMS for further verifying the correctness of the buffer parameter model and the autonomous docking capability. A laboratory platform is designed for on-the-ground experimental validation of the property of mini probe-cone docking mechanism. Repeated docking tests prove the proposed design of the mini probe-cone docking mechanism system for its high reliability, and automatic capture capability within large attitude range. The kinetic model of the docking capture process and the mechanism structure could provide some references for similar m

关键词： docking mechanism numerical simulation virtual prototype capture buffer parameter

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Discrete Variable Structural Optimization based on Multidirectional Fuzzy Genetic Algorithm

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Chinese Journal of Mechanical Engineering 2012年第2期25卷 255-261页

作者： LAI Yinan dai ye BAI Xue CHEN Dongyan School of Mechanical and Power Engineering Harbin University of Science and TechnologyHarbin 150080China School of Applied Science Harbin University of Science and TechnologyHarbin 150080China

Round method is the common method for discrete variable optimization in optimal design of complex mechanical structures;however,it has some disadvantages such as poor precision,simple model and lacking of working conditions＇ description,*** solve these problems,a new model is constructed by defining parameterized fuzzy entropy,and the rationality of parameterized fuzzy entropy is *** a new multidirectional searching algorithm is further put forward,which takes information of actual working conditions into consideration and has a powerful local searching *** this new algorithm is combined with the GA by the fuzzy clustering algorithm（FCA）.With the application of FCA,the optimal solution can be effectively filtered so as to retain the diversity and the elite of the optimal solution,and avoid the structural re-analysis phenomenon between the two *** structure design of a high pressure bypass-valve body is used as an example to make a structural optimization by the proposed HGA and finite element method（FEM）,*** comparison result shows that the improved HGA fully considers the characteristic of discrete variable and information of working conditions,and is more suitable to the optimal problems with complex working ***,the research provides a new approach for discrete variable structure optimization problems.

关键词： parameterized fuzzy entropy fuzzy clustering analysis multidirectional searching algorithm genetic algorithm high pressure bypass-valve

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Electrocatalytic Activity of Pt/C Electrodes for Ethanol Oxidation in Vapor Phase

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Chemical Research in Chinese Universities 2005年第5期21卷 597-600页

作者： LIANG Hong ye dai-qi LIN Wei-ming School of Biological and Chemical Engineering Guangzhou University Guangzhou 510091 P. R. China School of Environment Science and Engineering South China University of Technology Guangzhou 510640 P. R. China

High performance platinized-carbon electrodes have been developed for the electrocatalytic oxidation of ethanol to acetaldehyde in electrogenerative processes. A load current density of the electrode can be achieved as high as 600 mA per square centimeter for oxygen reducing in 3 mol/L sulfuric acid with a good stability. With these electrodes and sulfuric acid as an electrolyte in fuel cells, ethanol vapor carried by nitrogen gas can be oxidized selectively to acetaldehyde. Selectivity of acetaldehyde depends on the potential of the cell and the feed rate of ethanol vapor and it can be more than 80% under optimized conditions. The initial product of ethanol oxidized on a platinized-carbon electrode is acetaldehyde and the ethanol oxidation mechanism is discussed.

关键词： Ethanol Platinum Electrocatalytic oxidation Acetaldehyde

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Structural stability and magnetism of metastable Ni-Pt intermetallic compounds studied by ab initio calculation

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Science China(Technological Sciences) 2009年第9期52卷 2681-2687页

作者： CHE XingLai LI JiaHao dai ye LIU BaiXin Advanced Materials Laboratory Department of Materials Science and EngineeringTsinghua UniversityBeijing 100084China

The self-consistent electronic structure calculations were carried out with the accurate frozen-core full-potential projector augmented-wave method on 13 Ni-Pt intermetallic compounds of simple crystalline structures,i.e. A15,D019,D03 and L12 Ni3Pt and NiPt3,and α-NiAs,B1,B2,L2a,and L10 NiPt. The calculations reveal that the L12 Ni3Pt,L10 NiPt and L12 NiPt3 are energetically more stable than their respective competitive structures,indicating that the three structures may be formed in some appropriate conditions. The obtained results match well with the experimental observation or other theory predictions. It is found that there is hybridization between Ni 3d and Pt 5d states,which may significantly affect the structural stability and magnetism of metastable Ni-Pt intermetallic compounds.

关键词： ab initio study magnetism metastable phases

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Formation of non-equilibrium phases and associated structural transition in the Pd-Ta system induced by ion beam mixing

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Science China(Technological Sciences) 2011年第3期54卷 676-681页

作者： ZHAO Man dai ye LI JiaHao LIU BaiXin Advanced Materials Laboratory Department of Materials Science and Engineering Tsinghua University Beijing 100084 China

For the Pd-Ta system characterized by a negative heat of formation of -78 kJ/mol, 200 keV xenon ion beam mixing with nano-sized Pd-Ta multilayered films was conducted to study the non-equilibrium phase formation. The results showed that uniform amorphous alloys can be formed within a composition range of 25 at%-78 at% Ta, which falls in the maximum possible amorphization range of 22 at%-80 at% Ta predicted by the empirical model. Moreover, two metastable crystalline phases both of FCC structure, yet with different lattice constants were obtained. Interestingly, a self-assembled fractal pattern was observed in the Pd52Ta48 multilayered films after irradiation to a dose of 1×1015 Xe+/cm2 and its dimension was determined to be 1.75±0.05. The possible mechanisms for the formation of amorphous and metastable crystalline phases as well as for the growth of the fractal pattern were discussed.

关键词： amorphous phase Pd-Ta alloy ion beam mixing metastable crystalline phase fractal

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Toluene removal characteristics by a superimposed wire-plate dielectric barrier discharge plasma reactor

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Journal of Environmental Sciences 2006年第2期18卷 276-280页

作者： GUO Yu-fang ye dai-qi CHEN Ke-fu College of Resource Science and Paper-making Engineering South China University of Technology Guangzhou 510640 China College of Environmental Science and Engineering South China University of Technology Guangzhou 510640 China

A superimposed wire-plate dielectric barrier discharge reactor was used to remove toluene in this study. The effects of oxygen content, gas flow rate, gas initial concentration and with/without catalyst on toluene decomposition were investigated. It was found that an optimal toluene removal was achieved when the oxygen content was about 5%. Under this condition, the highest toluene removal efficiency of 80.8% was achieved when the gas concentration was 80 mg/m^3. The toluene removal efficiency decreased with the increase of the gas flow rate and the initial concentration of toluene. In addition, the ozone concentration decreased with the increase of the initial concentration of toluene. It suggested that combining DBD （dielectric barrier discharge） with Co3O4/Al2O3/foam nickel catalyst in-situ could improve the toluene removal efficiency and suppress ozone formation. Products analysis showed that the main products were CO and CO2 when oxygen was more than 5%.

关键词： dielectric barrier discharge(DBD) plasma oxygen content catalyst toluene product analysis

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Study on the optimal incident proton energy of ^(7)Li(p,n)^(7)Be neutron source for boron neutron capture therapy

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Nuclear Science and Techniques 2024年第3期35卷 170-180页

作者： Yi-Nan Zhu Zuo-Kang Lin Hai-Yan Yu ye dai Zhi-Min dai Xiao-Han Yu Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Science Beijing 100049China

Boron neutron capture therapy(BNCT)is recognized as a precise binary targeted radiotherapy technique that effectively eliminates tumors through the^(10)B(n,α)^(7)Li nuclear *** various neutron sources,accelerator-based sources have emerged as particularly promising for BNCT ***^(7)Li(p,n)^(7)Be reaction is highly regarded as a potential neutron source for BNCT,owing to its low threshold energy for the reaction,significant neutron yield,appropriate average neutron energy,and additional *** study utilized Monte Carlo simulations to model the physical interactions within a lithium target subjected to proton bombardment,including neutron moderation by an MgF_(2)moderator and subsequent BNCT dose analysis using a Snyder head *** study focused on calculating the yields of epithermal neutrons for various incident proton energies,finding an optimal energy at 2.7 ***,the Snyder head phantom was employed in dose simulations to validate the effectiveness of this specific incident energy when utilizing a^(7)Li(p,n)^(7)Be neutron source for BNCT purposes.

关键词： Boron neutron capture therapy ^(7)Li(p,n)7Be neutron source Incident proton energy Monte Carlo simulation

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Different atomic structures observed from ternary Ni-Nb-Ta metallic glasses obtained by ion beam mixing

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Science China(Technological Sciences) 2013年第8期56卷 1842-1846页

作者： WANG YuanYu LIU JianBo dai ye LIU BaiXin Advanced Materials Laboratory School of Materials Science and EngineeringTsinghua University

Four sets of ternary Ni-Nb-Ta multilayered samples with overall compositions of Ni69Nb8Ta23,Ni55Nb13Ta32,Ni42Nb16Ta42 and Ni29Nb18Ta53,respectively were prepared and subjected to 185 keV xenon ion beam *** experimental results showed that in the four Ni-Nb-Ta multilayered samples,metallic glasses could all be obtained at appropriate doses,supporting the prediction directly from a proven realistic Ni-Nb-Ta interatomic potential through molecular dynamics simulations,and that two different atomic structures were observed,as in the corresponding selected area diffraction patterns,the locations of the diffused bands reflected from the metallic glass phases were observed at different angles for the Ni69Nb8Ta23 and Ni29Nb18Ta53 metallic ***,Voronoi tellessation analysis indicated that the observed difference in atomic structures could be attributed to the distinct coordinate number spectra,i.e.,the spectrum of the Ni69Nb8Ta23 metallic glass has its coordinate number(CN) equal to 13 as dominating atomic configuration(with a weight of about 27%),whereas for the Ni29Nb18Ta53 metallic glass,CN=14 is the dominating atomic configuration(also about 27%).Moreover,the distinct atomic configurations of the obtained Ni-Nb-Ta metallic glasses could be correlated to the structures of the constituent metals of the ternary Ni-Nb-Ta system,as the first neighbor of fcc is 12 and the sum of the first and second neighbors of bcc is 14,implying the structural heredity did play a role in metallic glass formation.

关键词： ion beam mixing molecular dynamics coordinate number structural heredity

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Comparisons and applications of numerical simulation methods for predicting aerodynamic heating around complex configurations

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Acta Mechanica Sinica 2011年第3期27卷 339-345页

作者： Jin-Ling Luo Hong-Lin Kang Jian Li Wu-ye dai Northwestern Polytechnical University 710072 Xi'an China Beijing Electro-Mechanical Engineering Institute100074 Beijing China

Numerical simulation methods of aerodynamic heating were compared by considering the inuence of numerical schemes and turbulence models,and attempting to investigate the applicability of numerical simulation methods on predicting heat flux in engineering applications. For some typical cases provided with detailed experimental data,four spatial schemes and four turbulence models were adopted to calculate surface heat flux. By analyzing and comparing,some inuencing regularities of numerical schemes and turbulence models on calculating heat flux had been acquired. It is clear that AUSM＋-up scheme with rapid compressibilitymodified high Reynolds number k鈥撓？model should be appropriate for calculating heat flux. The numerical methods selected as preference above were applied to calculate the heat flux of a 3-D complex geometry in high speed turbulent flows. The results indicated that numerical simulation can capture the complex flow phenomena and reveal the mechanism of aerodynamic heating. Especially,the numerical result of the heat flux at the stagnation point of the wedge was well in agreement with the prediction of Kemp鈥揜iddel formula,and the surface heat flux distribution was consistent with experiment results,which implied that numerical simulation can be introduced to predict heat flux in engineering applications.

关键词： Aerodynamic heating . Complex configurations . Numerical simulation

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Review of key technologies of climbing robots

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Frontiers of Mechanical Engineering 2023年第4期18卷 79-96页

作者： ye dai Shikun LI Xukun RUI Chaofang XIANG Xinlei NIE Key Laboratory of Advanced Manufacturing Intelligent Technology of Ministry of Education Harbin University of Science and TechnologyHarbin 150080China

In recent years,the robot industry has developed rapidly,and researchers and enterprises have begun to pay more attention to this *** are barely familiar with climbing robots,a kind of special ***,from their practical value and scientific research value,climbing robots should studied *** paper analyzes and summarizes the key technologies of climbing robots,introduces various kinds of climbing robots,and examines their advantages and disadvantages to provide a reference for future *** countries have studied climbing robots and made some ***,due to the complexity of climbing robots,their climbing efficiency and accuracy need to be further *** new structure can improve the climbing *** paper analyzes climbing robots such as mechanical arms,magnetic attraction,and *** methods and path planning can improve the accuracy of *** paper involves some control methods,including complex intelligent control methods such as behavior-based robot *** paper also investigates various kinematic planning methods and expounds and summarizes various path planning algorithms,including machine learning and reinforcement learning of artificial intelligence,ant colony algorithm,and other ***,by analyzing the research status of climbing robots at home and abroad,this paper summarizes three important aspects of climbing robots,namely,structural design,control methods,and climbing strategies,elaborates on the achievements and existing problems of these key technologies,and looks forward to the future development trend and research direction of climbing robots.

关键词： climbing robot mechanical structure design control system kinematics planning path planning

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