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Aharonov-Bohm Interferometer in a T-Shaped Quantum Dot Embedded in Majorana Bound States

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Communications in Theoretical Physics 2019年第8期71卷 1024-1028页

作者： fu-bin Yang Department of Physics and Atmospheric Lidar Institute Civil Aviation Flight University of China

We theoretically study the spin-dependent transport properties of an Aharonov-Bohm(AB) interferometer composed by a T-shaped quantum dot(QD) embedded in Majorana bound states(MBS).We use the equation of motion method to calculate the conductance across the *** note that the conductance exhibits sensitive dependence on the MBS-QD coupling strength as well as the polarization strength of the leads when the phase factor of AB ring changes *** conductance shows a transition from resonance to anti-resonance when the MBSQD coupling strength changes from small to ***, there is different p-dependence conductance when the leads alignment changes from parallel to *** findings suggest that such a model could be used for a sensitive detection of MBS interactions, exploiting the high sensitivity of conductance to the AB phase in the interferometer.

关键词： Aharonov-Bohm effect Majorana bound states quantum dot

A Network Decomposition Model for Rubber-Like Materials Considering Topological Constraints

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Acta Mechanica Solida Sinica 2018年第6期31卷 785-793页

作者： bin fu Xiaoxiang Yang Qing Li College of Mechanical and Electrical Engineering Shaoxing UniversityShaoxing 312099China College of Mechanical Engineering and Automation Fuzhou UniversityFuzhou 350108China College of Mechanical and Electronic Engineering Fujian Agriculture and Forestry UniversityFuzhou 350108China

A molecular network constitutive model is proposed in this *** on the concept of molecular network decomposition,the molecular network was decomposed into a James-Guth 3-chain network model and an Arruda-Boyce 8-chain network *** that the single molecular chain of rubber is constrained by the surrounding molecular networks, the 3-chain model and the 8-chain model were consequently modified using the tube *** proposed model contains four material parameters that were determined by fitting the uniaxial tensile test data from rubber-like materials,and the values of these parameters were utilized to determine the pure shear and the biaxial *** proposed model agrees well with the experimental data and can predict the test results of experiments performed under the conditions of pure shear and equi-biaxial deformation with acceptable accuracy.

关键词： Hyperelastic Network decomposition Rubber-like materials Constitutive model Tube model

An FEM approximation for a fourth-order variational inequality of second kind

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Applied Mathematics(A Journal of Chinese Universities) 2008年第1期23卷 19-24页

作者： QIAN fu-bin DING Rui School of Management Suzhou Univ. of Sci. ＆ Tech. Suzhou 215008 China. School of Math. Sci. Suzhou Univ. Suzhou 215006 China. Corresponding author.

A fourth-order variational inequality of the second kind arising in a plate frictional bending problem is considered. By using regularization method, the original problem can be formulated as a differentiable variational equation, and the corresponding discrete FEM variational equation is presented afterwards. Abstract error estimates and error estimates of the approximation are derived in terms of energy norm and L^2-norm.

关键词： plate theory variational inequality of the second kind fourth-order problem FEM regularization error estimate.

Smart homing guidance strategy with control saturation against a cooperative target-defender team

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Journal of Systems Engineering and Electronics 2019年第2期30卷 366-383页

作者： GUO Hang fu Wenxing fu bin CHEN Kang YAN Jie School of Astronautics Northwestern Polytechnical University

A smart homing guidance strategy with control saturation against a target-defender team is derived. It is noteworthy that a cooperative strategy of the target-defender team is applied,which has been proved more challenging for the homing *** defender missile is launched by the target and guided by a cooperative augmented proportional navigation(APN). At the same time, the target performs a one-switch maneuver to cooperate and minimize the defender's acceleration requirement. The problem is analyzed for arbitrary-order linear dynamics of the agents in the linearized form but validated by the mathematical simulations by using nonlinear kinematics. The perfect information of three agents' states is assumed. Then, a method to deal with the target-defender team is proposed. It contains a combined performance index penalizing the miss distance relative to the target and energy consumption in the whole duration. Besides, the specific miss distance related to the defender is regarded as an inequality constraint. An analytical solution for the smart guidance strategy against the APN guided defender is derived. Meanwhile, the control saturations are introduced to get more realistic and reasonable insights to this practical target-missile-defender problem. A simple but effective iterative searching technique is proposed to determine the saturation time points. The solution provides an optimal homing strategy to evade the defender with a specific miss distance and intercept the target with the minimum miss distance in the minimum energy manner. Nonlinear two-dimensional simulation results are used to validate the theoretical analysis. By comparison with the optimal differential game guidance(ODGG) and the combined minimum effort guidance(CMEG), the superiority of this smart guidance strategy is concluded.

关键词： smart homing guidance control saturation targetmissile-defender iterative searching technique

Understanding Tunneling Ionization of Atoms in Laser Fields using the Principle of Multiphoton Absorption

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Chinese Physics Letters 2019年第4期36卷 19-23页

作者： Long Xu Li-bin fu Graduate School of China Academy of Engineering Physics

The elaborate energy and momentum spectra of ionized electrons from atoms in laser fields suggest that the ionization dynamics described by tunneling theory should be modified. Although great efforts have been carried out within semiclassical models, there are few discussions describing the multiphoton absorption process within a quantum framework. Comparing the results obtained with the time-dependent Schr?dinger equation(TDSE)and the Keldysh–Faisal–Reiss(KFR) theory, we study the nonperturbative effects of ionization dynamics beyond the KFR theory. The difference in momentum spectra between multiphoton and tunneling regimes is understood in a unified picture with virtual multiphoton absorption processes. For the multiphoton regime, the momentum spectra can be obtained by coherent interference of each periodic contribution. However, the interference of multiphoton absorption peaks will result in a complex structure of virtual multiphoton bands in the tunneling regime. It is shown that the virtual spectra will be almost continuous in the tunneling regime instead of the discrete levels found in the multiphoton regime. Finally, with a model combining the TDSE and the KFR theory,we try to understand the different effects of virtual multiphoton processes on ionization dynamics.

关键词： Laser Multiphoton Absorption ionized electrons

The runoff characteristics under simulated rainfall on purple soil sloping cropland

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Chinese Journal Of Geochemistry 2011年第3期30卷 317-322页

作者： XU Pei fu bin Key Laboratory of Mountain Surface Process and Hazards Chinese Academy of Sciences Chengdu 610041 China Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China

Rainfall runoff is a critical hydrological process related to soil erosion and agricultural non-point pollu-tion. In this study, 25 simulation experiments on rainfall were carried out in five runoff plots. Rape (Brassica campestris) was planted on the downslope of the plots. Experiments were conducted when the vegetation coverage reached 80%. Each plot was subjected to five rainfall events differing in intensity. The results showed: (1) the runoff coefficients of overland flow and subsurface flow were less than 0.6 and 0.005, respectively; (2) the discharge of overland flow was the quadratic function of time; (3) runoff coefficient was the function of slope gradient and rain-fall intensity. When the slope gradient increased from 8.7% to 46.6%, the runoff coefficient of overland flow first increased and then decreased. The runoff coefficient reached the maximum when the slope gradient was within the range of 17.6%-36.4%; and (4) the process of subsurface flow generation included the increasing phase and reces-sion phase. Discharge was a logarithm function of time in the increasing phase, and an exponential function in the recession phase. Runoff coefficient of subsurface flow decreased first and then increased when the slope gradient varied from 8.7% to 46.6% and was not correlated with rainfall intensity.

关键词：模拟降雨径流特性紫色土坡耕地农业非点源污染径流系数降雨强度径流小区

Impact angle constrained fuzzy adaptive fault tolerant IGC method for Ski-to-Turn missiles with unsteady aerodynamics and multiple disturbances

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Journal of Systems Engineering and Electronics 2022年第5期33卷 1210-1226页

作者： GUO Hang WANG Zheng fu bin CHEN Kang fu Wenxing YAN Jie Research Center for Unmanned System Strategy Development Northwestern Polytechnical UniversityXi’an 710072China Unmanned System Research Institute Northwestern Polytechnical UniversityXi’an 710072China

An impact angle constrained fuzzy adaptive fault tolerant integrated guidance and control method for Ski-to-Turn(STT)missiles subject to unsteady aerodynamics and multiple disturbances is *** aerodynamics appears when flight vehicles are in a transonic state or confronted with unstable ***,actuator failures and multisource model uncertainties are ***,the boundaries of these multisource uncertainties are assumed *** target is assumed to execute high maneuver movement which is unknown to the ***,impact angle constraint puts forward higher requirements for the interception accuracy of the integrated guidance and control(IGC)*** impact angle constraint and the precise interception are established as the object of the IGC ***,the boundaries of the lumped disturbances are estimated,and several fuzzy logic systems are introduced to compensate the unknown nonlinearities and ***,a series of adaptive laws are developed so that the undesirable effects arising from unsteady aerodynamics,actuator failures and unknown uncertainties could be ***,an impact angle constrained fuzzy adaptive fault tolerant IGC method with three loops is constructed and a perfect hit-to-kill interception with specified impact angle can be ***,the numerical simulations are conducted to verify the effectiveness and superiority of the proposed method.

关键词： integrated guidance and control(IGC) impact angle constraint unsteady aerodynamics fault tolerant control(FTC) actuator failures

Aero-thermal heating constrained midcourse guidance using state-constrained model predictive static programming method

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Journal of Systems Engineering and Electronics 2018年第6期29卷 1263-1270页

作者： fu bin GUO Hang CHEN Kang fu Wenxing WU Xingyu YAN Jie School of Astronautics Northwestern Polytechnical UniversityXi’an 710072China Xi’an Microelectronic Technology Institute Xi’an 710065China

This paper proposes a multiple-constraints-guaranteed midcourse guidance law for the interception of the hypersonic targets. In traditional midcourse law design, the constraints of the aero-thermal heating are rarely taken into consideration. The performance of the infrared detection system may be degraded and the instability of the flight control system may be *** address this problem, a state-constrained model predictive static programming method is introduced such that both terminal constraints(position and angle) and optimal energy consumption can be ensured. As a result, a sub-optimal midcourse guidance,guaranteeing the aforementioned multiple-constraints to be never violated, is synthesized. Simulation results demonstrate the effectiveness of the proposed method.

关键词： midcourse guidance model predictive control optimal control state constraint

Simulation of SLD Impingement on Wind Turbine Blade Airfoil

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Transactions of Nanjing University of Aeronautics and Astronautics 2016年第1期33卷 112-120页

作者： Zhu Chengxiang Zhu Chunling fu bin ZhaoHuanyu Key Laboratory of fundamental Science for National Defense Advanced Design Technology of Flight Vehicle Nanjing University of Aeronautics and AstronauticsNanjing 210016P.R.China Science and Technology on Space Physics Laboratory Beijing 100076P.R.China

Accurate prediction of droplet impingement on wind turbine blade is one of the most important premises of anti-icing and de-icing system *** a super-cooled large droplets(SLD)conditions,droplet no longer maintains a sphere shape,and it may deform,break up,and splash when moving or impinging on the ***-empirical models of droplet dynamic behaviours are embedded into the Eulerian droplet model to improve the accuracy of the numerical simulation of droplet impingement limits and local collection *** droplet model(Model 1)for small droplets and improved Eulerian droplet model(Model 2)for large droplet are both validated by comparing to the wind tunnel experiment *** the proposed methods,droplet impingement limitation and local collection efficiency on the S809 airfoil are calculated in various conditions.A detailed derivation of Model 1and Model 2is presented along with a comparison of numerical trajectories,drag coefficient and collection efficiency *** results show that droplet dynamic behaviours,including splashing,break-up and deforming,must be considered to accurately simulate the impingement behaviour in the SLD *** with the increase of the droplet diameters,the effects of the droplet dynamic behaviors on the impingement characteristics are more obvious.

关键词： wind turbine icing super large droplet droplet deformation splash