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Science China(Technological Sciences) 2016年第9期59卷 1435-1441页

作者： deng YiMin zhu WeiRen DUAN HaiBin Bio-inspired Autonomous Flight Systems (BAFS) Research Group Science and Technology on Aircraft Control Laboratory Beihang University School of Automation Science and Electrical Engineering Beihang University

In this paper, a novel approach is proposed for solving the parameter design problem of brushless direct current(BLDC) motor, which is based on the membrane computing(MC) and pigeon-inspired optimization(PIO) algorithm. The motor parameter design problem is converted to an optimization problem with five design parameters and six constraints. The PIO algorithm is introduced into the framework of MC for improving the global convergence performance. The hybrid algorithm can improve the population diversity with better searching efficiency. Comparative simulations are conducted, and comparative results are given to show the feasibility and effectiveness of our proposed hybrid algorithm for high nonlinear optimization problems.

关键词： brushless direct current(BLDC) motor pigeon-inspired optimization(PIO) membrane computing(MC)

Double Andreev reflections at surface states of the topological insulators with hexagonal warping

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Frontiers of physics 2020年第2期15卷 79-86页

作者： Chang-Yong zhu Shi-Han Zheng Hou-jian Duan Ming-Xun deng Rui-Qiang Wang Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials School of Physics and Telecommunication EngineeringSouth China Normal UniversityGuangzhou 510006China School of Physics and Mechanical and Electrical Engineering Shaoguan UniversityShaoguan 512005China

We study the Andreev reflection(AR)at the interface of the topological insulator with hexagonal warping and superconductor *** to the hexagonal warping effect,the double ARs are found in a certain range of the incident angle,where for one incident electron beam,two beams of holes are reflected ***,both the beams of holes are reflected as retro-AR on the same side of the normal line of the interface but with different reflection angles,different from the previously reported double AR with one retro-AR and one *** double reflections owing to the warping effect show the optics-like property of the Dirac fermion and can stimulate the double reflections of light in anisotropic *** addition,we find that the double ARs are dependent on the hexagonal warping parameter nonmonotonically,and in an intermediate strength the double AR phenomenon is prominent,providing a possibility to explore the warping parameter of topological insulators.

关键词： Andreev reflection topological insulator warping effect

A desulphurization strategy for Sonogashira couplings by visible light/copper catalysis

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Organic Chemistry Frontiers 2022年第2期9卷 386-393页

作者： Xuan Li Min jiang Xiaolong zhu Xiuyan Song Qirong deng jian Lv Daoshan Yang Key Laboratory of Optic-electric Sensing and Analytical Chemistry for Life Science MOECollege of Chemistry and Molecular EngineeringQingdao University of Science and TechnologyQingdao266042P.R.China Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology(Ministry of Education) Department of ChemistryTsinghua UniversityBeijing 100084People’s Republic of China College of Materials Chemistry and Chemical EngineeringHangzhou Normal UniversityHangzhou310036P.R.China

The development of new copper-based catalysts in photoredox transformations has become a rapidly growing area of research and has been actively explored in the past several ***,we have developed a new copper-based catalyst,[(binap)(tpy)Cu]Cl,and applied it in the visible-light promoted Sonogashira coupling *** mild protocol results in various substituted alkynes from simple sulfonium salts which can be easily prepared from commercially available and inexpensive thiols,alcohols,and alkyl *** study will broaden the still limited strategies of copper photocatalysts in organic transformations.

关键词： copper visible coupling

Some applications of stochastic averaging method for quasi Hamiltonian systems in physics

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Science China(Physics,Mechanics & Astronomy) 2009年第8期52卷 1213-1222页

作者： deng MaoLin zhu WeiQiu Department of Mechanics State Key Laboratory of Fluid Power Transmission and ControlZhejiang UniversityHangzhou 310027China

Many physical systems can be modeled as quasi-Hamiltonian systems and the stochastic averaging method for quasi-Hamiltonian systems can be applied to yield reasonable approximate response *** the present paper,the basic idea and procedure of the stochastic averaging method for quasi Hamiltonian systems are briefly *** applications of the stochastic averaging method in studying the dynamics of active Brownian particles,the reaction rate theory,the dynamics of breathing and denaturation of DNA,and the Fermi resonance and its effect on the mean transition time are reviewed.

关键词： stochastic averaging method quasi Hamiltonian system Brownian motion reaction rate theory DNA denaturation Fermi resonance

Hydrogen and steam distribution following a small-break LOCA in large dry containment

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Nuclear Science and Techniques 2007年第3期18卷 181-185页

作者： deng jian CAO Xuewu School of Nuclear Science and Engineering Shanghai Jiaotong University Shanghai 200240 China

The hydrogen deflagration is one of the major risk contributors to threaten the integrity of the containment in a nuclear power plant, and hydrogen control in the case of severe accidents is required by nuclear regulations. Based on the large dry containment model developed with the integral severe-accident analysis tool, a small-break loss-of-coolant-accident (LOCA) without HPI, LPI, AFW and containment sprays, leading to the core degradation and large hydrogen generation, is calculated. Hydrogen and steam distribution in containment compartments is investi- gated. The analysis results show that significant hydrogen deflagration risk exits in the reactor coolant pump (RCP) compartment and the cavity during the early period, if no actions are taken to mitigate the effects of hydrogen accu- mulation.

关键词：氢蒸发严重事故氢分布小破口事故

Synthesis and Biological Activity of Philanthotoxin Analogs

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Chinese Chemical Letters 2006年第7期17卷 895-898页

作者： Yong An ZHANG Ke Zhong LIU deng Yuan WANG Yu zhu WANG Liang jian QU Chang Jin zhu Research Institute of Forest Ecology Environment and Protection CAE Beijing 100091 The College of Agronomy Xinjiang Agricultural University Urumqi 830052 Department of Applied Chemistry Beijing Institute of Technology Beijing 100081

The synthesis of four analogs of philanthotoxin is described. The preliminary bioassay showed that these compounds all had good insecticidal activities, and the compound 6a had the best killing effect.

关键词： PhTX synthesis biological activity

HIGH ACCURACY ANALYSIS OF TENSOR-PRODUCT LINEAR PENTAHEDRAL FINITE ELEMENTS FOR VARIABLE COEFFICIENT ELLIPTIC EQUATIONS

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Journal of Systems Science & Complexity 2012年第2期25卷 410-416页

作者： Jinghong LIU Yijun deng Qiding zhu Ningbo Institute of Technology Zhejiang University Department of Mathematics Hunan International Economics College College of Mathematics and Computer Science Hunan Normal University

For a general second-order variable coefficient elliptic boundary value problem in three dimensions, the authors derive the weak estimate of the first type for tensor-product linear pentahedral finite elements. In addition, the estimate for the W1,1-seminorm of the discrete derivative Green＇s function is given. Finally, the authors show that the derivatives of the finite element solution uh and the corresponding interpolant Hu are superclose in the pointwise sense of the L∞-norm.

关键词： Discrete derivative Green's function superconvergence tensor-product linear pentahedralfinite elements variable coefficient elliptic problem.

An Intrusion Detection Algorithm for Wireless Networks Based on ASDL

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IEEE/CAA Journal of Automatica Sinica 2018年第1期5卷 92-107页

作者： Weijun zhu Miaolei deng Qinglei Zhou School of Information Engineering Zhengzhou University College of Information Science and Engineering Henan University of Technology

Wireless networks are more vulnerable to cyberattacks than cable networks. Compared with the misuse intrusion detection techniques based on pattern matching, the techniques based on model checking(MC) have a series of comparative advantages. However, the temporal logics employed in the existing latter techniques cannot express conveniently the complex attacks with synchronization phenomenon. To address this problem, we formalize a novel temporal logic language called attack signature description language(ASDL). On the basis of it, we put forward an ASDL model checking algorithm. Furthermore, we use ASDL programs, which can be considered as temporal logic formulas,to describe attack signatures, and employ other ASDL programs to create an audit log. As a result, the ASDL model checking algorithm can be presented for automatically verifying whether or not the latter programs satisfy the formulas, that is, whether or not the audit log coincides with the attack signatures. Thus,an intrusion detection algorithm based on ASDL is obtained. The case studies and simulations show that the new method can find coordinated chop-chop attacks.

关键词： Attack signature description language(ASDL) intrusion detection(ID) model checking(MC) temporal logic

Theory assisted design of N-doped tin oxides for enhanced electrochemical CO2 activation and reduction

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Science China Chemistry 2019年第8期62卷 1030-1036页

作者： Congling Hu Lei Zhang Lulu Li Wenjin zhu Wanyu deng Hao Dong Zhi-jian Zhao Jinlong Gong Key Laboratory for Green Chemical Technology of Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityCollaborative Innovation Center of Chemical Science and Engineering (Tianjin)Tianjin 300072China Department of Mechanical and Materials Engineering Western UniversityLondonON N6A 5B9Canada

Clearly understanding the structure-function relationship and rational design of efficient CO2 electrocatalysts are still the *** article describes the molecular origin of high selectivity of formic acid on N-doped SnO2 nanoparticles,which obtained via thermal treatment of g-C3N4 and SnCl2·2H2O *** with density functional theory(DFT)calculations,we discover that N-doping effectively introduces oxygen vacancies and increases the charge density of Sn sites,which plays a positive role in CO2 *** addition,N-doping further regulates the adsorption energy of^*OCHO,^*COOH,^*H and promotes HCOOH *** from above modulation,the obtained N-doped SnO2 catalysts with oxygen vacancies(Ov-N-SnO2)exhibit faradaic efficiency of 93% for C1 formation,88% for HCOOH production and well-suppression of H2 evolution over a wide range of potentials.

关键词： N-doped SnO2 oxygen vacancy charge density CO2 activation electrochemical CO2 reduction

Optimal control strategies for stochastically excited quasi partially integrable Hamiltonian systems

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Acta Mechanica Sinica 2007年第3期23卷 311-319页

作者： Ronghua Huan Maolin deng Weiqiu zhu Department of Mechanics State Key Laboratory of Fluid Power Transmission and Control Zhejiang UniversityHangzhou 310027 China

In this paper two different control strategies designed to alleviate the response of quasi partially integrable Hamiltonian systems subjected to stochastic excitation are proposed. First, by using the stochastic averaging method for quasi partially integrable Hamiltonian systems, an n-DOF controlled quasi partially integrable Hamiltonian system with stochastic excitation is converted into a set of partially averaged It^↑o stochastic differential equations. Then, the dynamical programming equation associated with the partially averaged It^↑o equations is formulated by applying the stochastic dynamical programming principle. In the first control strategy, the optimal control law is derived from the dynamical programming equation and the control constraints without solving the dynamical programming equation. In the second control strategy, the optimal control law is obtained by solving the dynamical programming equation. Finally, both the responses of controlled and uncontrolled systems are predicted through solving the Fokker-Plank-Kolmogorov equation associated with fully averaged It^↑o equations. An example is worked out to illustrate the application and effectiveness of the two proposed control strategies.

关键词： Nonlinear system Stochastic excitation Stochastic averaging Optimal control Dynamical programming