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On the General and Resonant Solutions of Atoms Reflected by an Evanescent Laser Wave

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Chinese Physics Letters 1996年第8期13卷 587-589页

作者： TAN wei-han LI qiang-ning Department of Physics Shanghai UniversityShanghai 200072 and Shanghai Institute of Optics and fine Mechanics Chinese Academy of SciencesShanghai 201800

Usually the reflection of two level atoms by a detuning evanescent laser wave was studied in past few years.1-3 In previous paper we have presented an exact solution for this model based on the matrix Laplace transformation technique,and proceeded the numerical calculations for a given set of parameters.4 However in the special case of resonance interaction considered in this paper,the solution for Schrödinger wave equation and reflectivity calculation can be greatly simplified;besides,the resonant solution provides a check to the numerical data based on the general solution of the previous paper.

关键词： parameters wave simplified

Composite filtering with feedback information

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Journal of Systems Engineering and Electronics 2007年第1期18卷 54-56页

作者： He You Xiong wei Ma qiang Dept. of Electronic Engineering Naval Aeronautical Engineering Inst. Yantai 264001 P. R. China

The optimal fusion solution with feedback information for a hybrid multisensor data fusion system is presented. In this system, a part of sensors process their data locally to produce local tracks, and another part of sensors only provide detection reports These tracks and detection reports are communicated to a central site where track fusion and composite filtering are performed. The comparative results on the simulations suggest the feedback information from the center can greatly improve the tracking performance of the local node.

关键词： Data fusion Hybrid system Multisensor tracking Filtering

Sediment distribution pattern mapped from the combination of objective analysis and geostatistics in the large shallow Taihu Lake, China

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Journal of Environmental Sciences 2004年第6期16卷 908-911页

作者： LUOLian-cong QINBo-qiang ZHUGuang-wei NanjingInstituteofGeography＆Limnology ChineseAcademyofSciencesNanjing210008China

Investigation was made into sediment depth at 723 irregularly scattered measurement points which cover all the regions in Taihu Lake, China. The combination of successive correction scheme and geostatistical method was used to get all the values of recent sediment thickness at the 69×69 grids in the whole lake. The results showed that there is the significant difference in sediment depth between the eastern area and the western region, and most of the sediments are located in the western shore-line and northern regimes but just a little in the center and eastern parts. The notable exception is the patch between the center and Xishan Island where the maximum sediment depth is more than 4.0 m. This sediment distribution pattern is more than likely related to the current circulation pattern induced by the prevailing wind-forcing in Taihu Lake. The numerical simulation of hydrodynamics can strong support the conclusion. Sediment effects on water quality was also studied and the results showed that the concentrations of TP, TN and SS in the western part are obviously larger than those in the eastern regime, which suggested that more nutrients can be released from thicker sediment areas.

关键词： objective analysis geostatistics sediment distribution Taihu Lake

Interfacial intermetallic compound growth and shear strength of low-silver SnAgCuBiNi/Cu lead-free solder joints

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International Journal of Minerals,Metallurgy and Materials 2013年第9期20卷 883-889页

作者： Guo-qiang wei Lei Wang Xin-qiang Peng Ming-yang Xue School of Mechanical and Automotive Engineering South China University of Technology

The growth rule of the interfacial intermetallic compound （IMC） and the degradation of shear strength of ***-0.5Cu-2.0Bi-0.05Ni （SACBN）/Cu solder joints were investigated in comparison with Sn-3.0Ag-0.5Cu （SAC305）/ Cu solder joints aging at 373, 403, and 438 K. The results show that （Cul-x,Nix）6Sn5 phase forms between the SACBN solder and Cu substrate during soldering. The interracial IMC thickens constantly with the aging time increasing, and the higher the aging temperature, the faster the IMC layer grows. Compared with the SAC305/Cu couple, the SACBN/Cu couple exhibits a lower layer growth coefficient. The activation energies of IMC growth for SACBN/Cu and SAC305/Cu couples are 111.70 and 82.35 kJ/mol, respectively. In general, the shear strength of aged solder joints declines continuously. However, SACBN/Cu solder joints exhibit a better shear strength than SAC305/Cu solder joints.

关键词： soldering alloys soldered joints aging intermetallics activation energy shear strength

Dissipation-induced nonreciprocal magnon blockade in a magnon-based hybrid system

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Science China(Physics,Mechanics & Astronomy) 2022年第6期65卷 44-52页

作者： Yimin Wang wei Xiong Zhiyong Xu Guo-qiang Zhang Jian-qiang You Communications Engineering College Army Engineering University of PLANanjing 210007China Department of Physics Wenzhou UniversityWenzhou 325035China Interdisciplinary Center of Quantum Information State Key Laboratory of Modern Optical Instrumentationand Zhejiang Province Key Laboratory of Quantum Technology and DeviceSchool of PhysicsZhejiang UniversityHangzhou 310027China

We propose an experimentally realizable nonreciprocal magnonic device at the single-magnon level by exploiting magnon block-ade in a magnon-based hybrid *** coherent qubit-magnon coupling,mediated by virtual photons in a microwave cavity,leads to the energy-level anharmonicity of the composite *** contrast,the corresponding dissipative counterpart,induced by traveling microwaves in a waveguide,yields inhomogeneous broadenings of the energy *** a result,the cooperative effects of these two kinds of interactions give rise to the emergence of the direction-dependent magnon *** show that this can be demonstrated by studying the equal-time second-order correlation function of the magnon *** study opens an avenue to engineer nonreciprocal magnonic devices in the quantum regime involving only a small number of magnons.

关键词： nonreciprocal magnon blockade non-classical statistics dissipative coupling hybrid system

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Vacuum therapy in penile rehabilitation after radical prostatectomy： review of hemodynamic and antihypoxic evidence

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Asian Journal of Andrology 2016年第3期18卷 446-451,I0009,I0010页

作者： Sheng-qiang Qian Liang Gao qiang wei Jiuhong Yuan The Andrology Laboratory West China Hospital Sichuan University Chengdu 610041 China Department of Urology West China Hospital Sichuan University Chengdu610041 China

Generally, hypoxia is a normal physiological condition in the flaccid penis, which is interrupted by regular nocturnal erections in men with normal erectile function.1 Lack of spontaneous and nocturnal erections after radical prostatectomy due to neuropraxia results in persistent hypoxia of cavernosal tissue, which leads to apoptosis and degeneration of cavernosal smooth muscle fibers. Therefore, overcoming hypoxia is believed to play a crucial role during neuropraxia. The use of a vacuum erectile device （VED） in penile rehabilitation is reportedly effective and may prevent loss of penile length. The corporal blood after VED use is increased and consists of both arterial and venous blood, as revealed by color Doppler sonography and blood gas analysis. A similar phenomenon was observed in negative pressure wound therapy （NPWT）. However, NPWT employs a lower negative pressure than VED, and a hypoperfused zone, which increases in response to negative pressure adjacent to the wound edge, was observed. Nonetheless, questions regarding ideal subatmospheric pressure levels, modes of action, and therapeutic duration of VED remain unanswered. Moreover, it remains unclear whether a hypoperfused zone or PO2 gradient appears in the penis during VED therapy. To optimize a clinical VED protocol in penile rehabilitation, further research on the mechanism of VED, especially real-time PO2 measurements in different parts of the penis, should be performed.

关键词： oxygen penile rehabilitation tissue perfusion vacuum erectile device

A novel robust aerodynamic optimization technique coupled with adjoint solvers and polynomial chaos expansion

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Chinese Journal of Aeronautics 2022年第10期35卷 35-55页

作者： wei ZHANG qiang WANG Fanzhi ZENG Chao YAN National Key Laboratory of Computational Fluid Dynamics Beihang UniversityBeijing 100083China Aerospace Times Feipeng Company Limited China Academy of Aerospace Electronics TechnologyKunshan 215000China China Academy of Aerospace Aerodynamics Beijing 100074China

Uncertainty is common in the life cycle of an aircraft, and Robust Aerodynamic Optimization(RAO) that considers uncertainty is important in aircraft design. To avoid the curse of dimensionality in surrogate-based optimization, this study proposes an adjoint RAO technique called “R-Opt”. Polynomial Chaos Expansion(PCE) is coupled with the R-Opt technique to quantify uncertainty in the responses of the target(including its mean and standard deviation). Only one process of PCE model construction is required in each iteration, and the gradients of uncertainty can be inferred via chain rules. The proposed method is more efficient than prevalent methods,and avoids the problem of a disagreement over the best PCE basis from among a number of PCE models(especially in case of sparse PCE). It also supports the application of sparse *** benchmark tests and two airfoil cases were used to verify R-Opt, and the optimal solutions were deemed to be robust. It improved the mean aerodynamic performance and reduced the standard deviation of the target.

关键词： Adjoint technique Polynomial chaos expansion Robust design Uncertainty analysis Uncertainty gradient propagation

Optimizing the Copy-on-Write Mechanism of Docker by Dynamic Prefetching

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Tsinghua Science and Technology 2021年第3期26卷 266-274页

作者： Yan Jiang wei Liu Xuanhua Shi weizhong qiang National Engineering Research Center for Big Data Technology and System Services Computing Technology and System LabHuazhong University of Science and TechnologyWuhan 430074China

Docker,as a mainstream container solution,adopts the Copy-on-Write(CoW)mechanism in its storage *** mechanism satisfies the need of different containers to share the same ***,when a single container performs operations such as modification of an image file,a duplicate is created in the upper readwrite layer,which contributes to the runtime *** the accessed image file is fairly large,this additional overhead becomes *** we present the concept of Dynamic Prefetching Strategy Optimization(DPSO),which optimizes the Co W mechanism for a Docker container on the basis of the dynamic prefetching *** the beginning of the container life cycle,DPSO pre-copies up the image files that are most likely to be copied up later to eliminate the overhead caused by performing this operation during application *** experimental results show that DPSO has an average prefetch accuracy of greater than 78%in complex scenarios and could effectively eliminate the overhead caused by the CoW mechanism.

关键词： Docker container Copy-on-Write(CoW) storage driver prefetch strategy

Conceptual design and preliminary experiment of icing risk management and protection system

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Chinese Journal of Aeronautics 2022年第6期35卷 101-115页

作者： qiang WU Haojun XU Binbin PEI Yang wei School of Aeronautics Engineering Air Force Engineering UniversityXi’an 710038China

Icing is one of the main external environmental factors that causes aircraft to lose *** flight safety assurance system under icing condition is particularly ***,most of the systems do not consider the coupling characteristics of aerodynamics and flight dynamics of icing *** will affect the accuracy of the calculation ***,the icing risk management system helps the pilot to realize the possible dangers in advance and perform correct maneuvers,based on quantitative assessment and visualization methods of flight *** envelope protection system realizes flight safety guarantee based on the real-time boundary protection method of key flight ***,based on distributed simulation technology,a flight simulator was used as a platform to integrate the icing risk management system and envelope protection system to realize man-in-the-loop *** fictional but historically motivated icing scenarios are designed to test the system,and the results demonstrate that the icing risk management and protection system would be useful for aviation safety and can also be used for pilot training and reproducing flight accidents to find the causes.

关键词： Flight risk Flight simulator Icing Quantitative assessment Visualization