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Structures, Stabilities and Work Functions of Alkali-metal-adsorbed Boron α1-Sheets

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Chemical Research in Chinese Universities 2017年第4期33卷 631-637页

作者： yI Tingting ZHEng bing yU Haitao xie y.ng Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education School of Chemistry and Materials Science Heilongfiang University Harbin 150080 P. R. China

In this study, we employed the density functional theory method to simulate Li-, Na- and K-adsorbed boron α1-sheets（al-BSTs）. After optimizing possible structures, we investigated their thermodynamic stabilities, barriers for metal atom diffusion on the substrate, and work functions. The computed results indicate that the work function of α1-BST decreases significantly after the adsorption of Li, Na and K. Furthermore, under high hole coverage, these alkali-metal-adsorbed α1-BSTs have lower work functions than the two-dimensional materials of greatest concern and the commonly used electrode materials Ca and Mg. Therefore, the Li-, Na- and K-adsorbed α1-BSTs are potential low-work-function nanomaterials.

关键词： Boron α1-sheet Binding energy Migration barrier Alkali metal adsorption, Work function

Using Finite Element and Contour Method to Evaluate Residual Stress in Thick Ti-6Al-4V Alloy Welded by Electron Beam Welding

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Acta Metallurgica Sinica(English Letters) 2015年第7期28卷 922-930页

作者： Pu xie Hai-yan Zhao bing Wu Shui-Li Gong Department of Mechanical Engineering Tsinghua University State Key Laboratory of Tribology Tsinghua University Beijing Aeronautical Manufacture Technology Research Institute

This work was to reveal the residual stress profile in electron beam welded Ti-6Al-4V alloy plates（50 mm thick） by using finite element and contour measurement methods.A three-dimensional finite element model of 50-mmthick titanium component was proposed,in which a column–cone combined heat source model was used to simulate the temperature field and a thermo-elastic–plastic model to analyze residual stress in a weld joint based on ABAQUS *** the uncertainty of welding simulation,the computation was calibrated by experimental data of contour measurement *** test and simulated results show that residual stresses on the surface and inside the weld zone are significantly different and present a narrow and large gradient feature in the weld *** peak tensile stress exceeds the yield strength of base materials inside weld,which are distinctly different from residual stress of the thin Ti-6Al-4V alloy plates presented in references before.

关键词： Electron beam welding Residual stress Finite element method Contour method Titanium alloy

Toward accurate link between code and software documentation

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Science China(Information Sciences) 2018年第5期61卷 72-86页

作者： y.ngkui CAO yanzhen ZOU yuxiang LUO bing xie Junfeng ZHAO Key Laboratory of High Confidence Software Technologies Ministry of Education School of Electronics Engineering and Computer Science Peking University Beida (Binhai) Information Research

Recovering traceability links between source code and software documentation is an important research topic in software maintenance and software reuse. There have been a lot of research efforts in recovering traceability between documentation and code elements(class, interface, method, etc.), mostly based on program analysis. However, there are still a lot of noise links being established in existing work. In this paper, we propose a novel approach to classify.ng code elements, occurring in a document, into contextual code elements and salient code elements. As a result, we can filter the noise traceability links between a software document and its contextual code elements and get a higher quality link set. Our classifier is trained based on open source project Lucene’s source code and 1899 Stack Overflow answer documents about *** extract code elements from these documents and represent each of these code elements with a 7-dimension feature vector, then we use a decision-tree-based learning model to classify them as salient or not. In the experiments, we get a precision of 70.7% in recognizing the salient code elements of these documents and get12% improvement compared with Rigby’s work. We can filter out 56.5%～69.3% noise traceability links with different thresholds in our classifier. It can improve the quality of traceability links between source code and their related software documents in application.

关键词： traceability link code element software document contextual code element salient codeelement

A survey on recent progress in control of swarm systems

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Science China(Information Sciences) 2017年第7期60卷 5-28页

作者： bing ZHU Lihua xie Duo HAN Xiangyu MEng Rodney TEO School of Electrical and Electronic Engineering Nanyang Technological University The Seventh Research Division Beihang University Division of Systems Engineering Boston University Temasek Lab National University of Singapore

It has been witnessed that swarm systems are superior to individual agents in performing complicated tasks. In recent years, new results in some branches of control for swarm systems have developed and investigated with respect to various objectives and scenarios. This survey is to take a glimpse into some newly developed control techniques for swarm systems, especially those presented after 2013. The covered topics include some up-to-date progress in the areas of consensus, formation, flocking, containment, optimal coverage/mission planning, and sensor networks. Contributions and connections of the mentioned references are discussed *** on the new results in control of swarm systems, some possible new future research topics are suggested.

关键词： formation swarm systems consensus containment flocking sensor networks

Synthesis of TiO_2 nanoparticles by propane/air turbulent flame CVD process

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Particuology 2009年第3期7卷 204-210页

作者： Hongy.ng xie Guilan Gao Zhen Tian Naici bing Lijun Wang School of Urban Development and Environmental Engineering Shanghai Second Polytechnic University 2360 Jin Hal Road Pudong Shanghai 201209 China

Synthesis of TiO2 nanoparticles by the oxidation of titanium tetrachloride （TiCI4） in high-strength propane/air turbulent flame is investigated tentatively for mass production of TiO2 nanoparticles. Effects of reactor heat flux vary.ng from 247 to 627 kJ/m^2 s, initial TiO2 number density from 2 × 10^20 to 1 × 10^21 m^ 3, and apparent residence time of TiO2 nanoparticles in reactor from 0.06 to 0.9 s, on particle morphology, phase composition, UV absorption and photoluminescence （PL） spectra are studied. The TiO2 nanoparticles synthesized, with mean size of 30-80 nm and futile mass fraction from 0.155 up to 0.575, exhibited a strong PL signal at the wavelength of 370-450 nm, with a wide peak signal at 400-420 nm, reflecting significant oxygen vacancies on the surface of the TiO2 nanoparticles.

关键词： CVD Turbulent flame TiO2 nanoparticles PL spectra

Design and control of deformable quadrotor with vary.ng length arms

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Science China(Technological Sciences) 2023年第5期66卷 1225-1234页

作者： SUN yiChong xie MingNa LI yeHui ng Wingyin ZHAng Heng LI Zheng Multi-Scale Medical Robotics Centre The Chinese University of Hong KongHong Kong 999077China Department of Surgery The Chinese University of Hong KongHong Kong 999077China Department of Electrical and Electronic Engineering The University of Hong KongHong Kong 999077China College of Optoelectronic Engineering Chongqing UniversityChongqing 400044China

Deformable quadrotors can manipulate their specific structure for specialized tasks or excellent flight performance under diverse *** added deformation mechanism,the quadrotor exhibits higher flexibility;however,this is accompanied by difficulties in modeling analysis and controller design,which are crucial ***,a novel deformable quadrotor that can alter its arm's length is designed by combining the crank-slider mechanism and *** dynamics,including the attitude and position systems,are analyzed and the former is further described as switched linear parameter vary.ng(SLPV)systems from a control-oriented *** addition,a combined SLPV/proportion-integration-differentiation(PID)attitude controller is developed to handle different deformable quadrotor modes,which guarantees the stability of the closed-loop attitude system during the deformation process and achieves attitude ***,together with the cascade PID position controller,the entire flight controller is constructed whose feasibility is verified via fixed-point hovering and trajectory tracking experiments.

关键词： deformable quadrotor mechanics and control LPV systems switched control strategy specialized aerial system

Viscoelastic Characteristics of Fins, Muscle and Skin in Crucian Carp (Carassius Auratus) Described by the Fractional Zener Model

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Chinese Physics Letters 2011年第8期28卷 340-343页

作者： CHEN Ming JIA Lai-bing yIN xie-Zhen Department of Modern Mechanics University of Science and Technology of ChinaHefei 230027

Fish are supposed to be able to adapt to various underwater *** mechanical properties of the body of a fish is of essential importance in order to explore the source of high efficiency during fish *** investigate the viscoelastic properties of the fins,muscle and skin of Crucian carp(carassius auratus).A fractional Zener model is used to fit the relaxation force and the results show that the model can describe the relaxation process *** a Fourier transform,we discuss the response functions of the fins,muscle and skin of Crucian carp under the external excitation of a harmonic *** of these results with the cruising frequency of Crucian carp shows that the dissipation due to internal viscoelasticity during cruising is small.

关键词： fish relaxation Skin

A growing system: Constituent elements and spatial evolution of ancient local Confucian temples in China

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Frontiers of Architectural Research 2023年第5期12卷 966-984页

作者： bing xie y.ng Shen Xing Chen School of Architecture Southeast UniversityNanjing210096China Visual Image Research Base of Chinese Nation Southeast UniversityNanjing210096China

Taking the constituent elements other than the main buildings of local Confucian temples as a research object,including memorial archway,screen wall,Pan-chi(pond),worship altar,sacrificial hall,pavilion and tower,this paper combines textual narrative and historical measurement to sort out the production and development history of these constituent *** analyzes the spatial evolution trend of Confucian temples to present the dynamic processes of derivation of constituent elements and spatial evolution of local Confucian *** this basis,this paper surveys the causes of the growth of Confucian temples from a macro historical perspective by considering political,social and cultural *** dynamic development process,sacred and secular as it is,will grow and last forever under the multiple official implications and folk beliefs.

关键词： Confuciantemple Constituent elements Spatial evolution Causes

Low Temperature Direct Synthesis of Strontium Titanate Powder

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稀有金属材料与工程 2006年第A03期35卷 556-558页

作者： bing xie Shaohua Zhang Fengyi Li yumei Wu Center of Analysis and Testing Nanchang University Jiangxi 330047 China School of Materials Nanchang University Jiangxi 330047 China School of Science Nanchang University Jiangxi 330047 China

Low temperature direct synthesis (LTDS) involves the preparation of a base solution of Sr^(2+),and the mixing of base solution with tetrabutyl titanate *** is an advantageous method because it does not require the complex hydrothermal facilities and it can prevent the agglomeration in calcinations of other liquid *** our work,we adopted LTDS method to prepare the nano strontium titanate powders,and characterize them by XRD,FT-IR and *** influences of preparation temperature and solvents on grain size and lattice parameters were *** results show that preparation temperature can slightly change the lattice parameters of grain,while solvents also play important roles in the preparation.

关键词： SrTiO3 low temperature direct synthesis nano powder