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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 478-507页

作者： Cong-hua cheng School of Mathematics and Statistics Zhaoqing UniversityZhaoqing 526061China

In this paper,we consider a system which has k statistically independent and identically distributed strength components and each component is constructed by a pair of statistically dependent elements with doubly type-II censored *** elements(X1,Y1),(X2,Y2),…,(Xk,Yk)follow a bivariate Kumaraswamy distribution and each element is exposed to a common random stress T which follows a Kumaraswamy *** system is regarded as operating only if at least s out of k(1≤s≤k)strength variables exceed the random *** multicomponent reliability of the system is given by Rs,k=P(at least s of the(Z1,…,Zk)exceed T)where Zi=min(Xi,Yi),i=1,…,*** Bayes estimates of Rs,k have been developed by using the Markov Chain Monte Carlo methods due to the lack of explicit *** uniformly minimum variance unbiased and exact Bayes estimates of Rs,k are obtained analytically when the common second shape parameter is *** asymptotic confidence interval and the highest probability density credible interval are constructed for Rs,*** reliability estimators are compared by using the estimated risks through Monte Carlo simulations.

关键词： stress-strength model bivariate Kumaraswamy distribution multicomponent reliability doubly Type-II censored scheme interval estimation

Experimental and numerical investigation on the gas leakage regime for ventilated tail cavity of an underwater vehicle

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Journal of Hydrodynamics 2023年第1期35卷 46-60页

作者： Xiao-bo Quan Shao-hua cheng College of Shipbuilding Engineering Harbin Engineering UniversityHarbin150001China China Academy of Launch Vehicle Technology Beijing100076China Beijing Institute of Astronautical Systems Engineering Beijing100076China

The objective of this paper is mainly to investigate the ventilated tail cavity flow of an underwater vehicle with focus on the gas leakage regime by experimental and numerical methods.A high-speed camera and pressure measurement system are used to record the cavity flow patterns and pressure behavior,*** numerical simulation is carried out with volume of fluid(VOF)model and Filter-based turbulence model(FBM).Good agreement can be obtained between the experimental and numerical *** are three gas leakage types in the evolution of the intact tail cavity,i.e.,twin-vortex tube entrainment(TVTE),toroidal vortex shedding(TVS)and hybrid twin-vortex tube entrainment and toroidal vortex shedding(TVTE-TVS).With the increase of Fr,the unsteady behavior of the cavity with different gas leakage types becomes more *** internal flow characteristics revealed three distinct regions including the ventilation influence region,the reverse flow region and the high shear flow region and have an important effect on the transition of gas leakage regime.

关键词： Ventilated tail cavity gas leakage regime unsteady behavior internal flow characteristics

Two-dimension fluorescence correlation spectroscopy to characterize the binding of organic ligands with zinc in eutrophic lake

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Chinese Chemical Letters 2015年第2期26卷 205-209页

作者： Xin Liu hua Lv hua-cheng Xu College of Materials Science and Engineering Nanjing Forestry University State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and LimnologyChinese Academy of Sciences

Metal binding of organic ligands can definitely affect its environmental behavior in waters,while information on the binding heterogeneity with different organic ligands is still lacked till *** this study,the binding of zinc with organic matters associated with cyanobacterial blooms,including dissolved organic matters（DOM） and attached organic matters（AOM）,were studied by using fluorescence quenching titration combined with two-dimensional correlation spectroscopy（2D-COS）.Metal-induced fluorescent quenching was obviously observed both for DOM and AOM,indicating the formation of metal-ligand *** with the one-dimensional spectra,2D-COS revealed the sequences of metal-ligand interaction with the following orders：276 nm 〉 232 ran for DOM and232 nm 〉 276 nm for ***,the modified Stern-Volmer model showed that the binding constant（logKM） of 276 nm in DOM was higher than that of 232 nm（4.93 vs.4.51）,while AOM was characterized with a high binding affinity for 232 nm（log KM：4.83）.The ranks of log KM values were consistent with the sequential orders derived from 2D-COS results both for the two *** quenching titration combined with 2D-COS was an effective method to characterize the metal-ligand interaction.

关键词： Metal binding Eutrophic lakes Dissolved organic matters(DOM) Attached organic matters(AOM) Two-dimensional correlation spectroscopy(2D-COS)

Inflows/outflows driven particle dynamics in an idealised lake

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Journal of Hydrodynamics 2019年第5期31卷 873-886页

作者： cheng-hua Dang Jingchun Wang Qiuhua Liang School of Water Conservancy and Hydropower Hebei University of EngineeringHandan 056021China Jeremy Benn Associates Limited ColeshillWarwickshireUK School of Architecture Building and Civil EngineeringLoughborough UniversityLoughboroughUK

This paper considers fluid mixing driven by inflows connected to a circular shallow lake using a numerical framework consisting of a shallow water hydrodynamic model and a passive particle-tracking *** the flow field driven by alternate inflows predicted by a shallow water model,particle trajectories are traced out using a particle tracking *** horizontal fluid mixing dynamics are then interpreted using dynamics system analysis approaches including finite-time Lyapunov exponent(FTLE)and Lagrangian coherent structure(LCS).From the simulation results,it is confirmed that periodic inflows are able to create a weak dynamic system in an idealised circular lake,with the particle dynamics controlled by a single dimensionless parameter associated with the inflow *** mixing and transport property of the lake changes from regular to chaotic as the value of the dimensionless parameter increases until global chaotic particle dynamics is *** further analysing the advection of particles injected continuously to the inflows(freshwater),the fate of“freshwater”particles in a“polluted”lake is tracked and *** results provide useful guidance for engineering applications,i.e.,transferring freshwater from rivers to improve the water quality in polluted water bodies such as *** presented approach will be able to facilitate the design of‘optimised’schemes for such engineering implementation.

关键词： Shallow environmental flow Lagrangian particle dynamics particle tracking inflows and outflows finite-time Lyapunov exponent Lagrangian coherent structure

Few-layer metasurfaces with arbitrary scattering properties

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Science China(Physics,Mechanics & Astronomy) 2020年第8期63卷 2-13页

作者： Zhancheng Li Wenwei Liu hua cheng Shuqi Chen The Key Laboratory of Weak Light Nonlinear Photonics Ministry of EducationSchool of Physics and TEDA Institute of Applied PhysicsRenewable Energy Conversion and Storage CenterNankai UniversityTianjin 300071China The Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China Collaborative Innovation Center of Light Manipulations and Applications Shandong Normal UniversityJinan 250358China

Metasurfaces,which are planar arrays of subwavelength artificial structures,have emerged as excellent platforms for the integration and miniaturization of electromagnetic devices and provided ample possibilities for single-dimensional and multi-dimensional manipulations of electromagnetic ***,owing to the limited interactions between planar thin metallic nanostructures and electromagnetic waves as well as intrinsic losses in metals,metasurfaces exhibit disadvantages in terms of efficiency,controllability,and *** advances in this field show that few-layer metasurfaces can overcome these ***-layer metasurfaces composed of more than one functional layer enable more degrees of design ***,they possess unprecedented capabilities for electromagnetic wave manipulation,which have considerable impact in the area of *** article reviews recent advances in few-layer metasurfaces from the viewpoint of their scattering *** scattering matrix theory is briefly introduced,and the advantages and drawbacks of few-layer metasurfaces for the realization of arbitrary scattering properties are ***,a detailed overview of typical few-layer metasurfaces with various scattering properties and their design principles is ***,an outlook on the future directions and challenges in this promising research area is presented.

关键词： few-layer metasurfaces light-matter interaction scattering matrix full-space manipulation

SIMULATION OF FLUID-SOLID INTERACTION ON WATER DITCHING OF AN AIRPLANE BY ALE METHOD

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Journal of Hydrodynamics 2011年第5期23卷 637-642页

作者： hua cheng FANG Chao cheng Jin Department of Mechanics and Engineering Science Fudan University Shanghai 200433 China School of Mathematical Sciences Fudan University Shanghai 200433 China

Ditching is considered as one of the important aspects of safety performances of airplanes. It is related primarily with the fluid-solid interaction, whose studies mainly depend on experiments at the present time. Numerical and analytical methods for fluid-solid interaction by using 3-D full scale airplane＇s model will reduce the dependence on the expensive model tests. Numerical studies can be used to estimate the safety of ditching and provide a reference for the crashworthiness design. This article proposes a 3-D dynamical structural model after the real shape of an airplane and an Arbitrary Lagrange-Euler （ALE） fluid-field model, to simulate the fluid-solid interactions caused by low speed ditching. The simulation is based on interaction computational methods, within LS-DYNA nonlinear finite-element code. The results of pressure distributions and accelerating time histories of the airplane＇s subfloor are discussed in the context of the safety of ditching, and the simulation results and the analytical methods are verified.

关键词： ditching fluid structure interaction Arbitrary Lagrange-Euler (ALE) finite element method

Third harmonic distortion calculation of a self-oscillating power amplifier

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第4期12卷 307-316页

作者： Yu-hua cheng Nian-xiong TAN Institute of VLSI Design Zhejiang University Hangzhou 310027 China

It is difficult to analyze the harmonic distortion of a self-oscillating power amplifier (SOPA),because the SOPA is a hard nonlinear system without an external *** single or multiple sinusoidal inputs describing function (DF) method is commonly used to linearize a nonlinear element,but this method considers only the components at the same frequencies as the input signals (i.e.,fundamental components) at the nonlinear element's *** this paper,besides the fundamental components,the third harmonic components are also calculated at the output of a comparator with three sinusoidal inputs,to create a linearized model of the comparator,and thus of the *** third harmonic distortion of the SOPA is *** models of the zeroth and the first order SOPA are verified by behavioral simulation using MATLAB.

关键词： Describing function (DF) Comparator Self-oscillating power amplifier (SOPA) Third harmonic distortion

New Exact Traveling Wave Solutions for Compound KdV-Type Equation with Nonlinear Terms of Any Order

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Communications in Theoretical Physics 2006年第5X期46卷 787-792页

作者： DU Xing-hua LIU cheng-Shi Department of Mathematics Daqing Petroleum Institute Daqing 163318 China

The compound KdV-type equation with nonlinear terms of any order is reduced to the integral form. Using the complete discrimination system for polynomial, its all possible exact traveling wave solutions are obtained. ... 详细信息

关键词： compound KdV-type equation complete discrimination system for polynomial traveling wavesolution evolution equation

Ruin Probabilities for a Two-Dimensional Perturbed Risk Model with Stochastic Premiums

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Acta Mathematicae Applicatae Sinica 2016年第4期32卷 1053-1066页

作者： Jian-hua cheng De-hui WANG School of Mathematics Jilin University

In this paper, we consider a two-dimensional perturbed risk model with stochastic premiums and certain dependence between the two marginal surplus processes. We obtain the Lundberg-type upper bound for the infinite-time ruin probability by martingale approach, discuss how the dependence affects the obtained upper bound and give some numerical examples to illustrate our results. For the heavy-tailed claims case, we derive an explicit asymptotic estimation for the finite-time ruin probability.

关键词： two-dimensional risk model ruin probability upper bound dependent risk asymptotic estimate

Manipulation of multi-transparency windows and fast-slow light transitions in a hybrid cavity optomechanical system

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Science China(Physics,Mechanics & Astronomy) 2019年第5期62卷 75-83页

作者： Ming-hua Zheng Tie Wang Dong-Yang Wang cheng-hua Bai Shou Zhang cheng-Shou An Hong-Fu Wang Department of Physics College of Science Yanbian University Department of Physics Harbin Institute of Technology

We study the generation of quadruple-transparency windows and the implementation of a conversion between slow and fast light in a hybrid optomechanical system. By demonstrating the generation of these transparency windows one by one, we analyze the physical mechanism through which each transparency window forms in detail. Additionally, we discuss how the system parameters affect the formation of transparency windows and conclude that the location, width, and absorption of each transparency window can be arbitrarily manipulated by varying the appropriate parameters. Moreover, when the pump field is changed from red to blue detuning, conversions between slow and fast light occur in the output field. These interesting properties of the output field can be applied to achieve the coherent control and manipulation of light pulses using cavity optomechanical system.

关键词： hybrid cavity optomechanical system optomechanical induced transparency fast-slow light