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Influence of time-periodic potentials on electronic transport in double-well structure

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Chinese Physics B 2010年第5期19卷 488-493页

作者：李春雷徐燕 college of elementary educational Capital Normal University

Within the framework of the Floquet theorem, we have investigated single-electron photon-assisted tunneling in a double-well system using the transfer matrix technique. The transmission probability displays satellite peaks on both sides of the main resonance peaks and these satellite peaks originate from emission or absorption photons. The single-electron resonance tunneling can be controlled through changing the applied harmonically potential positions, such as driven potential in wells, in barriers, or in whole double-well systems. This advantage should be useful in the optimization of the parameters of a transmission device.

关键词： photon-assisted tunneling transmission probability quantum well

Capturability-based Fuzzy Footstep Planner for a Biped Robot with Centroidal Compliance

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Journal of Bionic Engineering 2024年第1期21卷 84-100页

作者： Zihan Xu Qin Fang Yong Ren Chengju Liu Robot and Artificial Intelligence Lab(RAIL) College of Electronic and Information EngineeringTongji UniversityShanghai 201804China Applied Technology college Soochow UniversitySuzhou 215000China

Compliance motion and footstep adjustment are active balance control strategies from learning human subconscious *** force estimation without direct end-actuator force measurement and the optimal footsteps based on complex analytical calculation are still challenging tasks for elementary and kid-size position-controlled *** this paper,an online compliant controller with Gravity Projection Observer(GPO),which can express the external force condition of perturbations by the estimated Projection of Gravity(PoG)with estimation covariance,is proposed for the realization of disturbance absorption,with which the robustness of the humanoid contact with environments can be *** fuzzy footstep planner based on capturability analysis is proposed,and the Model Predictive Control(MPC)is applied to generate the desired *** fuzzification rules are well-designed and give the corresponding control output responding to complex and changeable external *** validate the presented methods,a series of experiments on a real humanoid robot are *** results verify the effectiveness of the proposed balance control framework.

关键词： Biped walking Centroidal compliance Gravity projection observer Fuzzy footstep planner

Teachers’Multicultural Awareness and the Ethnic Identity of Minority Students:An Individual Case Study of a Hani Student

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Frontiers of Education in China 2012年第2期7卷 212-226页

作者： OU Qunhui DU Na The elementary educational college Capital Normal UniversityBeijing 100048China

This study considers the role of teachers’multicultural awareness in promoting minority students’ethnic identity by considering the situation in one particular middle school.A case study of a Hani student is presented to show how teachers’multicultural awareness affects ethnic identity and the academic achievement of minority *** case study enables the authors to assess the significance and value of teachers’multicultural awareness as an educational *** the study,the authors point to a need to strengthen multicultural awareness in teachers’education to meet requirements of cultural *** authors also emphasize that such awareness should be an objective of teacher training.

关键词： minority students ethnic identity teachers’multicultural awareness

A module based modeling framework for estimating lunar dust deposition due to human activities

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Chinese Journal of Aeronautics 2024年第2期37卷 501-510页

作者： Chunjian PAN college of Automation Engineering Shanghai University of Electric PowerShanghai 200090China

Lunar dust is considered to be one of the top challenges for enabling humans to have extended stays on the *** activities such as module landings and launches,walking,rover operation and construction activities will inevitably produce a significant amount of ***,it is important to estimate the potential range and intensity of dust deposition caused by these activities to minimize dust accumulation over time and for maintenance planning and execution.A modular model that correlates the dust deposition distribution with initial mean dust particle velocity,its mean ejected angle and the total amount of ejected mass is developed for an elementary mechanical *** modular model is further employed to form a modeling framework to estimate dust deposition of a trajectory based activity of similar repeated movements such as the landing process of a lander,walking and rover *** model forms a unified modeling framework for different trajectory-based activities and is shown to predict consistent and physically meaningful ranges and intensities of dust deposition provided reliable data to calibrate the model parameters.

关键词： Lunar dust Dust deposition Lunar lander Lunar construction Model calibration

Characteristic modification by inserted metal layer and interface graphene layer in ZnO-based resistive switching structures

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Chinese Physics B 2018年第2期27卷 522-526页

作者：刘浩男索晓霞张林奥张端吴汉春赵宏康江兆潭李英兰王志 School of Physics Beijing Institute of Technology elementary educational college Beijing Key Laboratory for Nano-Photonics and Nano-Structure Capital Normal University

ZnO-based resistive switching device Ag/ZnO/TiN, and its modified structure Ag/ZnO/Zn/ZnO/TiN and Ag/graphene/ZnO/TiN, were prepared. The effects of inserted Zn layers in ZnO matrix and an interface graphene layer on resistive switching characteristics were studied. It is found that metal ions, oxygen vacancies, and interface are involved in the RS process. A thin inserted Zn layer can increase the resistance of HRS and enhance the resistance ratio. A graphene interface layer between ZnO layer and top electrode can block the carrier transport and enhance the resistance ratio to several times. The results suggest feasible routes to tailor the resistive switching performance of ZnO-based structure.

关键词： resistive switching ZnO graphene multilayer thin films

The relations among the three kinds of conditional risk measures

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Science China Mathematics 2014年第8期57卷 1753-1764页

作者： GUO TieXin ZHAO ShiEn ZENG XiaoLin School of Mathematics and Statistics Central South University elementary educational college Capital Normal University college of Mathematics and Statistics Chongqing Technology and Business University

Let（Ω , E, P） be a probability space, F a sub-σ-algebra of E, L^p（E）（1 p ＋∞） the classical function space and LF^p（E） the L^0（F）-module generated by L^p（E）, which can be made into a random normed module in a natural way. Up to the present time, there are three kinds of conditional risk measures, whose model spaces are L^∞（E）, L^p（E）（1 p ＋∞） and LF^p（E）（1 p ＋∞） respectively, and a conditional convex dual representation theorem has been established for each kind. The purpose of this paper is to study the relations among the three kinds of conditional risk measures together with their representation theorems. We first establish the relation between L^p（E） and LF^p（E）, namely LF^p（E） = Hcc（L^p（E））, which shows that LF^p（E）is exactly the countable concatenation hull of L^p（E）. Based on the precise relation, we then prove that every L^0（F）-convex L^p（E）-conditional risk measure（1 p ＋∞） can be uniquely extended to an L^0（F）-convex LF^p（E）-conditional risk measure and that the dual representation theorem of the former can also be regarded as a special case of that of the latter, which shows that the study of L^p-conditional risk measures can be incorporated into that of LF^p（E）-conditional risk measures. In particular, in the process we find that combining the countable concatenation hull of a set and the local property of conditional risk measures is a very useful analytic skill that may considerably simplify and improve the study of L^0-convex conditional risk measures.

关键词： random normed module countable concatenation property L^∞(E)-conditional risk measure L^p(E)-conditional risk measure(1≤ p 〈 +∞) LF^p(E)-conditional risk measure(1 ≤p≤ +∞) extension

Adaptive generalized projective synchronization of two different chaotic systems with unknown parameters

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Chinese Physics B 2008年第11期17卷 4073-4079页

作者：张若洵杨世平 college of Physics Hebei Normal University The elementary Education college Xingtai University

This paper presents a general method of the generalized projective synchronization and the parameter identification between two different chaotic systems with unknown parameters. This approach is based on Lyapunov stability theory, and employs a combination of feedback control and adaptive control. With this method one can achieve the generalized projective synchronization and realize the parameter identifications between almost all chaotic （hyperchaotic） systems with unknown parameters. Numerical simulations results are presented to demonstrate the effectiveness of the method.

关键词： different chaotic systems generalized projective synchronization parameter identification unknown parameters

Bifunctional core–shell co-catalyst for boosting photocatalytic CO_(2) reduction to CH_(4)

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Nano Research 2024年第3期17卷 1259-1266页

作者： Fangxu Dai Mingming Zhang Jishu Han Zhenjiang Li Shouhua Feng Jun Xing Lei Wang Key Laboratory of Eco-chemical Engineering Ministry of EducationCollege of Chemistry and Molecular EngineeringQingdao University of Science and TechnologyQingdao 266042China college of Materials Science and Engineering Qingdao University of Science and TechnologyQingdao 266042China college of Environment and Safety Engineering Qingdao University of Science and TechnologyShandong Engineering Research Center for Marine Environment Corrosion and Safety ProtectionQingdao 266042China

Solar-light-driven CO_(2) reduction CO to CH_(4) and C2H6 is a complex process involving multiple elementary reactions and energy ***,achieving high CH_(4) activity and selectivity remains a significant ***,we integrate bifunctional Cu2O and Cu-MOF(MOF=metal-organic framework)core–shell co-catalysts(Cu2O@Cu-MOF)with semiconductor TiO_(2).Experiments and theoretical calculations demonstrate that Cu2O(Cu+facilitates charge separation)and Cu-MOF(Cu2+improves the CO_(2) adsorption and activation)in the core–shell structure have a synergistic effect on photocatalytic CO_(2) reduction,reducing the formation barrier of the key intermediate*COOH and**** photocatalyst exhibits high CH_(4) yield(366.0μmol·g^(-1)·h^(-1)),efficient electron transfer(3283μmol·g^(-1)·h^(-1))and hydrocarbon selectivity(95.5%),which represents the highest activity of Cu-MOF-based catalysts in photocatalytic CO_(2) reduction *** work provides a strategy for designing efficient photocatalysts from the perspective of precise regulation of components.

关键词： bifunctional co-catalyst core–shell photocatalytic CO_(2)reduction

Optimization of Generator Based on Gaussian Process Regression Model with Conditional Likelihood Lower Bound Search

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CES Transactions on Electrical Machines and Systems 2024年第1期8卷 32-42页

作者： Xiao Liu Pingting Lin Fan Bu Shaoling Zhuang Shoudao Huang CES&IEEE the college of Electrical and Information Engineering Hunan UniversityChangsha 410082China CES

The noise that comes from finite element simulation often causes the model to fall into the local optimal solution and over fitting during optimization of ***,this paper proposes a Gaussian Process Regression(GPR)model based on Conditional Likelihood Lower Bound Search(CLLBS)to optimize the design of the generator,which can filter the noise in the data and search for global optimization by combining the Conditional Likelihood Lower Bound Search *** the efficiency optimization of 15 kW Permanent Magnet Synchronous Motor as an ***,this method uses the elementary effect analysis to choose the sensitive variables,combining the evolutionary algorithm to design the super Latin cube sampling plan;Then the generator-converter system is simulated by establishing a co-simulation platform to obtain data.A Gaussian process regression model combing the method of the conditional likelihood lower bound search is established,which combined the chi-square test to optimize the accuracy of the model ***,after the model reaches the accuracy,the Pareto frontier is obtained through the NSGA-II algorithm by considering the maximum output torque as a ***,the constrained optimization is transformed into an unconstrained optimizing problem by introducing maximum constrained improvement expectation(CEI)optimization method based on the re-interpolation model,which cross-validated the optimization results of the Gaussian process regression *** above method increase the efficiency of generator by 0.76%and 0.5%respectively;And this method can be used for rapid modeling and multi-objective optimization of generator systems.

关键词： Generator optimization Gaussian Process Regression(GPR) Conditional Likelihood Lower Bound Search(CLLBS) Constraint improvement expectation(CEI) Finite element calculation