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A review of multiple optical vortices generation: methods and applications

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Frontiers of Optoelectronics 2019年第1期12卷 52-68页

作者： long zhu Jian WANG Wuhan National Laboratory for Optoelectronics School of Optical and Electronic InformationHuazhong University of Science and TechnologyWuhan 430074China

Optical vortices carrying orbital angular momentum(OAM)have attracted increasing interest in recent *** vortices have seen a variety of emerging applications in optical manipulation,optical trapping,optical tweezers,optical vortex knots,imaging,microscopy,sensing,metrology,quantum information processing,and optical *** various optical vortices enabled applications,the generation of multiple optical vortices is of great *** this review article,we focus on the methods of multiple optical vortices generation and its *** review the methods for generating multiple optical vortices in three cases,i.e.,1-to-N collinear OAM modes,1-to-N OAM mode array and N-to-N collinear OAM *** applications of multiple OAM modes in optical communications and non-communication areas are *** trends,perspectives and opportunities are also discussed.

关键词： optical communications optical vortices orbital angular momentum (OAM) mode-division multiplexing (MDM) mode multicasting

Studies on parallel seismic testing for integrity of cemented soil columns

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第11期8卷 1746-1753页

作者： HUANG Da-zhi CHEN long-zhu Institute of Engineering Safety and Disaster Prevention Dept. of Civil Engineering Shanghai Jiao Tong University Shanghai 200240 China

The principle and process of parallel seismic (PS) testing for the integrity testing of cemented soil columns are in- troduced in this paper. A three-dimensional (3D) finite element model (FEM) for the pile-soil system is established for impulse responses. Under saturated soil or unsaturated soil condition, several vibrating velocity-time histories at different depths in parallel hole are obtained based on the numerical simulation. It shows that the length of the pile and the one-dimensional (1D) P-wave velocity in the pile can be determined easily from the features of the mentioned velocity-time histories. By examining the slopes of the first arrival time plotted versus depth or the depth where the amplitude of the first arrival significantly decreases, the length of the pile can be determined. The effects of the 3D P-wave propagation through the saturated soil and the defect of the cemented soil column on the velocity-time histories are also investigated.

关键词： Parallel seismic (PS) testing Cemented soil columns Integrity testing Numerical simulation

Secondary decay effects of the isospin fractionation in the projectile fragmentation at GeV/nucleon

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Nuclear Science and Techniques 2020年第12期31卷 122-128页

作者： Chen-Chen Guo Jun Su long zhu Sino-French Institute of Nuclear Engineering and Technology Sun Yat-sen UniversityZhuhai 519082China

The isospin fractionations in 124Sn,107Sn+120Sn at 600 MeV/nucleon,and 136Xe,124Xe+208Pb at 1000 MeV/nucleon are investigated by the isospin-dependent quantum molecular dynamics model coupled with the statistical code *** yield ratio as a function of the binding energy difference for light mirror nuclei 3H/3He,7Li/7Be,11B/11C,and 15N/15O is applied to estimate the ratio between neutrons and protons in the gas of the fragmenting *** comparing the estimated values resulting from the simulations with and without the GEMINI code,it was found that the secondary decay distorts the signal of the isospin *** minimize the secondary decay effects,the yield ratio of the light mirror nuclei 3H/3He as well as its double ratio between two systems with different isospin asymmetries of the projectiles is recommended as robust isospin observables.

关键词： Quantum molecular dynamics model(QMD) Isospin fractionation Secondary decay effect

Scale properties of turbulent transport and coherent structure in stably stratified flows

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Applied Mathematics and Mechanics(English Edition) 2016年第4期37卷 443-458页

作者： long zhu Xiang QIU Jianping LUO Yulu LIU School of Mechanical Engineering Shanghai Institute of Technology School of Science Shanghai Institute of Technology Shanghai Institute of Applied Mathematics and Mechanics Shanghai University

The empirical mode decomposition （EMD） is used to study the scale properties of turbulent transport and coherent structures based on velocity and temperature time series in stably stratified turbulence. The analysis is focused on the scale properties of intermittency and coherent structures in different modes and the contributions of energy-contained coherent structures to turbulent scalar counter-gradient transport （CGT）. It is inferred that the velocity intermittency is scattered to more modes with the development of the stratified flow, and the intermittency is enhanced by the vertical stratification, especially in small scales. The anisotropy of the field is presented due to different time scales of coherent structures of streamwise and vertical velocities. There is global counter-gradient heat transport close to the turbulence-generated grid, and there is local counter-gradient heat transport at certain modes in different positions. Coherent structures play a principal role in the turbulent vertical transport of temperature.

关键词： stratified turbulence coherent structure counter-gradient transport (CGT),empirical mode decomposition (EMD)

Effects of vertical excitation on the seismic performance of a seismically isolated bridge with sliding friction bearings

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Earthquake Engineering and Engineering Vibration 2016年第1期15卷 187-196页

作者： Wang Changfeng Zhao Jikang zhu long Bao Yijun School of Civil Engineering Yantai University School of Civil Engineering Lanzhou Jiaotong University

A finite element model is constructed for a sliding friction bearing in a seismically isolated bridge under vertical excitation with contact/friction elements. The effects of vertical excitation on the seismic performance of a seismically isolated bridge with sliding friction bearings and different bearing friction coefficients and different stiffness levels （pier diameter） are discussed using example calculations, and the effects of excitation direction for vertical excitation on the analysis results are explored. The analysis results shows that vertical excitation has a relatively large impact on seismic performance for a seismically isolated bridge with sliding friction bearings, which should be considered when designing a seismically isolated bridge with sliding friction bearings where vertical excitation dominates.

关键词： vertical excitation seismically isolated bridge sliding friction bearing seismic analysis

Verification of neutron-induced fission product yields evaluated by a tensor decompsition model in transport-burnup simulations

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Nuclear Science and Techniques 2023年第2期34卷 190-201页

作者： Qu‑Fei Song long zhu Hui Guo Jun Su School of Nuclear Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China Sino‑French Institute of Nuclear Engineering and Technology Sun Yat-sen UniversityZhuhai 519082China

Neutron-induced fission is an important research object in basic ***,its product yield data are an indispensable nuclear data basis in nuclear engineering and *** fission yield tensor decomposition(FYTD)model has been developed and used to evaluate the independent fission product *** general,fission yield data are verified by the direct comparison of experimental and evaluated ***,such direct comparison cannot reflect the impact of the evaluated data on application scenarios,such as reactor transport-burnup ***,this study applies the evaluated fission yield data in transport-burnup simulation to verify their accuracy and possibility of ***,the evaluated yield data of235U and239Pu are applied in the transport-burnup simulation of a pressurized water reactor(PWR)and sodium-cooled fast reactor(SFR)for *** the reactor operation stage,the errors in pin-cell reactivity caused by the evaluated fission yield do not exceed 500 and 200 pcm for the PWR and SFR,*** errors in decay heat and135Xe and149Sm concentrations during the short-term shutdown of the PWR are all less than 1%;the errors in decay heat and activity of the spent fuel of the PWR and SFR during the temporary storage stage are all less than 2%.For the PWR,the errors in important nuclide concentrations in spent fuel,such as90Sr,137Cs,85Kr,and99Tc,are all less than 6%,and a larger error of 37%is observed *** the SFR,the concentration errors of ten important nuclides in spent fuel are all less than 16%.A comparison of various aspects reveals that the transport-burnup simulation results using the FYTD model evaluation have little difference compared with the reference results using ENDF/B-Ⅷ.0 *** proves that the evaluation of the FYTD model may have application value in reactor physical analysis.

关键词： Fission product yield Tensor decomposition Transport-burnup simulation Machine learning

Study on determination of the stable slope configuration for deep open pit mine

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第9期9卷 1208-1213页

作者： Nai-long zhu Shi-xiong ZHANG Shu-yu YUE School of Civil Engineering and Architecture Wuhan University of Technology Wuhan 430070 China School of Resources and Environment Engineering Wuhan University of Technology Wuhan 430070 China

The space effects of deep pit slope are analyzed by an elastic mechanics principle. The interaction among the critical slide angle, the friction coefficient, the cohesion, and the horizontal radius of the deep pits is derived in this paper. It indicates that the deeper the pit is excavated, the greater the critical slide angle is. Both the theory for reducing stripping waste rock in deep pit and the approach to determining the configuration of the stable slope are developed from the interaction. The theory in this paper comprises the preceding principles of stability analysis of slopes and is suitable for analyzing that of deep pit.

关键词： Elastic mechanics Deep pit Slope stability Critical slide angle Ratio of stripping-to-ore

Chain store game based channel allocation in cognitive radio system

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The Journal of China Universities of Posts and Telecommunications 2010年第1期17卷 1-8页

作者： LI Jin-long zhu Ping WANG Xu-fa School of Computer Science and Technology University of Science and Technology of China Hefei 230027 China

In adaptive channel allocation for secondary user （SU） of cognitive radio （CR） system, it is necessary to consider allocation process from the temporal perspective. In this article, a chain store game is modeled to achieve SU＇s equilibrium state. Due to the computational complexity of solving equilibrium states, the authors explore the correlated equilibrium （CE） by importing signal mechanisms based on time and sequence number. Also, correlated equilibrium based game algorithms are presented. Simulations show that these algorithms are superior to other allocation algorithms both in channel utilization and communication time.

关键词： CR dynamic specturm allocation chain store game Nash equilibrium (NE) correlated equilibrium (CE)

Modeling complex networks of nuclear reaction data for probing their discovery processes

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Chinese Physics C 2021年第12期45卷 114-121页

作者： Xiaohang Wang long zhu Jun Su Sino-French Institute of Nuclear Engineering and Technology Sun Yat-sen UniversityZhuhai 519082China

Hundreds of thousands of experimental data sets of nuclear reactions have been systematically collected,and their number is still growing *** data and their correlations compose a complex system,which underpins nuclear science and *** model the nuclear reaction data as weighted evolving networks for the purpose of data verification and *** networks are employed to study the growing cross-section data of a neutron induced threshold reaction(n,2n)and photoneutron *** the networks,the nodes are the historical data,and the weights of the links are the relative deviation between the data *** is found that the networks exhibit small-world behavior,and their discovery processes are well described by the Heaps *** makes the networks novel is the mapping relation between the network properties and the salient features of the database:the Heaps exponent corresponds to the exploration efficiency of the specific data set,the distribution of the edge-weights corresponds to the global uncertainty of the data set,and the mean node weight corresponds to the uncertainty of the individual data *** new perspective to understand the database will be helpful for nuclear data analysis and compilation.

关键词： modeling complex networks neutron induced threshold reaction photoneutron reaction nuclear database