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Numerical Simulation of the Vortex-Induced Vibration of A Curved Flexible Riser in Shear Flow

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China Ocean Engineering 2018年第3期32卷 301-311页

作者： zhu Hong-jun LIN Peng-zhi State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum University State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University

A series of fully three-dimensional(3 D) numerical simulations of flow past a free-to-oscillate curved flexible riser in shear flow were conducted at Reynolds number of 185–1015. The numerical results obtained by the two-way fluid–structure interaction(FSI) simulations are in good agreement with the experimental results reported in the earlier study. It is further found that the frequency transition is out of phase not only in the inline(IL) and crossflow(CF) directions but also along the span direction. The mode competition leads to the non-zero nodes of the rootmean-square(RMS) amplitude and the relatively chaotic trajectories. The fluid–structure interaction is to some extent reflected by the transverse velocity of the ambient fluid, which reaches the maximum value when the riser reaches the equilibrium position. Moreover, the local maximum transverse velocities occur at the peak CF amplitudes, and the values are relatively large when the vibration is in the resonance regions. The 3 D vortex columns are shed nearly parallel to the axis of the curved flexible riser. As the local Reynolds number increases from 0 at the bottom of the riser to the maximum value at the top, the wake undergoes a transition from a two-dimensional structure to a 3 D one. More irregular small-scale vortices appeared at the wake region of the riser, undergoing large amplitude responses.

关键词： vortex-induced vibration flexible riser shear flow fluid–structure interaction computational fluid dynamics

Brief Communications:QTLNetworkR:an interactive R package for QTL visualization

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第7期11卷 512-515页

作者： Wen-jun ZHENG Jian YANG jun zhu Institute of Bioinformatics Zhejiang University Hangzhou 310029 China Queensland Institute of Medical Research Brisbane Queensland 4006 Australia

QTLNetworkR is an R package that aims to provide a user-friendly and platform-independent tool to visualize quantitative trait loci (QTL) mapping results. The graphical functions of the QTLNetworkR are based upon lattice and grid packages, and the graphical user interface (GUI) of the QTLNetworkR is built upon RGtk2 and gWidgetsRGtk2 packages. Six functions are designed to help visualize marker interval, putative QTL, QTL-by- environment interactions, marker interval interactions, epistasis, and the predicted genetic architecture of complex traits. It is especially helpful in profiling results for multiple traits at multiple environments. The current version of QTLNetworkR is able to accept QTL mapping results from QTLNetwork, and it is ready for possible extensions to import results from some other QTL mapping software packages. In addition, we presented a QTL mapping result in rice (Oryza sativa) as an example to describe the features of QTLNetworkR.

关键词： Visualization Quantitative trait loci (QTL) QTL mapping R package QTLNetworkR

Solving algorithm for TA optimization model based on ACO-SA

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Journal of Systems Engineering and Electronics 2011年第4期22卷 628-639页

作者： jun Wang Xiaoguang Gao Yongwen zhu School of Electronic and Information Technology Northwestern Polytechnical University Xi'an 710072 P. R. China Radar and EW Institute Equipment Academy of Air Force Beijing 100085 R R. China

An ant colony optimization （ACO）-simulated annealing （SA）-based algorithm is developed for the target assignment problem （TAP） in the air defense （AD） command and control （C2） system of surface to air missile （SAM） tactical unit. The accomplishment process of target assignment （TA） task is analyzed. A firing advantage degree （FAD） concept of fire unit （FU） intercepting targets is put forward and its evaluation model is established by using a linear weighted synthetic method. A TA optimization model is presented and its solving algorithms are designed respectively based on ACO and SA. A hybrid optimization strategy is presented and developed synthesizing the merits of ACO and SA. The simulation examples show that the model and algorithms can meet the solving requirement of TAP in AD combat.

关键词： target assignment (TA) optimization ant colony optimization (ACO) algorithm simulated annealing (SA) algorithm,hybrid optimization strategy.

Carbon deposition and catalytic deactivation during CO_2 reforming of CH_4 over Co/MgO catalyst

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Chinese Journal of Chemical Engineering 2018年第11期26卷 2344-2350页

作者： Jianwei Li jun Li Qingshan zhu State Key Laboratory of Multiphase Complex Systems Institute of Process EngineeringChinese Academy of Sciences State Key Laboratory of Heavy Oil Processing China University of Petroleum School of Chemical Engineering University of Chinese Academy of Sciences

The deactivation mechanism of Co/MgO catalyst for the reforming of methane with carbon dioxide was investigated. The conversion of CH4 displayed a significant decrease in the initial stage caused by carbon *** were two types of cokes, carbon nanotubes(CNTs) and carbon nano-onions(CNOs). The number of the CNO layers that coated on the surface of Co nanoparticles(NPs) increased rapidly in the initial reforming time,which was responsible for the deactivation of the Co/MgO catalyst. The deposition of CNOs was attributed to the oxidation of Co NPs. Therefore, the deactivation of the Co/MgO catalyst was originated from the first oxidization of the Co NPs into Co3 O4 by O species(OH intermediate, CO_2, H2 O) during the reforming reaction,which accelerates the formation of coke that blocked the active metal, thus led to catalyst deactivation.

关键词： Co/MgO CH4 reforming Carbon deposition Co oxidization

Study of ADS-B Data Evaluation

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Chinese Journal of Aeronautics 2011年第4期24卷 461-466页

作者： ZHANG jun LIU Wei zhu Yanbo School of Electronics and Information Engineering Beihang University Beo'ing 100191 China CNS Department Aviation Data Communication Corporation Beijing 100191 China

In western China, the terrain and meteorological conditions are so complex that it is not suitable to construct new radar stations. Automatic dependent surveillance-broadcast （ADS-B） is a totally new surveillance method, so before practically applied and operated in China, abundant tests and evaluations are necessary to validate the performance of ADS-B and guarantee the operational security. During the flight tests, we collect the data of radar, ADS-B and high accuracy position and compare the performance of ADS-B with radar based on high accuracy position. To solve the asynchronous problem among radar data, ADS-B data and real-time kinematic （RTK） data caused by different update rates, this *** proposes the technique of synchronizing multi-surveil- lance data by extrapolating from the data of low update rate to high update rate according to velocity and heading. Meanwhile, because radar data, ADS-B data and RTK data are expressed in different coordinates and cannot be compared each other, this article provides a method to unifying the coordinates of multi-surveillance data. By the analysis and evaluation, we can conclude that the performance of ADS-B is better than radar.

关键词： civil aviation surveillance ADS-B accuracy integrity flight inspection data evaluation

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上位性及其在遗传育种研究中的应用

生物信息学 2004年第2期2卷 39-41,50页

作者：张文英程君奇朱军吴为人浙江大学生物信息学研究所浙江杭州310029

上位性引入遗传学已有一个多世纪,直到近些年才受到广泛关注,成为复杂性状遗传研究体系的一个重要组成部分。上位性可分为统计上位性和功能上位性两类,前者具有群体特性,后者属于基因型现象。分子标记技术是研究上位性的一个有力工具,... 详细信息

上位性引入遗传学已有一个多世纪,直到近些年才受到广泛关注,成为复杂性状遗传研究体系的一个重要组成部分。上位性可分为统计上位性和功能上位性两类,前者具有群体特性,后者属于基因型现象。分子标记技术是研究上位性的一个有力工具,理论与实验研究证实上位性在动植物数量性状的表现中具有重要作用。上位性在作物育种中的应用因作物的繁殖方式,育种方法等不同而异,上位性是杂种优势形成的重要遗传基础。

关键词：上位性遗传学育种数量性状基因座

New Finite Difference Mapped WENO Schemes with Increasingly High Order of Accuracy

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Communications on Applied Mathematics and Computation 2023年第1期5卷 64-96页

作者： jun zhu Jianxian Qiu College of Science Nanjing University of Aeronautics and AstronauticsNanjing 210016JiangsuChina School of Mathematical Sciences and Fujian Provincial Key Laboratory of Mathematical Modeling and High-Performance Scientific Computing Xiamen UniversityXiamen 361005FujianChina

In this paper,a new type of finite difference mapped weighted essentially non-oscillatory(MWENO)schemes with unequal-sized stencils,such as the seventh-order and ninthorder versions,is constructed for solving hyperbolic conservation *** the purpose of designing increasingly high-order finite difference WENO schemes,the equal-sized stencils are becoming more and more *** more we use wider candidate stencils,the bigger the probability of discontinuities lies in all ***,one innovation of these new WENO schemes is to introduce a new splitting stencil methodology to divide some fourpoint or five-point stencils into several smaller three-point *** the usage of this new methodology in high-order spatial reconstruction procedure,we get different degree polynomials defined on these unequal-sized stencils,and calculate the linear weights,smoothness indicators,and nonlinear weights as specified in Jiang and Shu(***.126:202228,1996).Since the difference between the nonlinear weights and the linear weights is too big to keep the optimal order of accuracy in smooth regions,another crucial innovation is to present the new mapping functions which are used to obtain the mapped nonlinear weights and decrease the difference quantity between the mapped nonlinear weights and the linear weights,so as to keep the optimal order of accuracy in smooth *** new MWENO schemes can also be applied to compute some extreme examples,such as the double rarefaction wave problem,the Sedov blast wave problem,and the Leblanc problem with a normal CFL *** numerical results are provided to illustrate the good performance of the new finite difference MWENO schemes.

关键词： Finite difference Mapped WENO scheme Mapping function Mapped nonlinear weight Unequal-sized stencil Extreme example

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

Physical characteristics with SPP in the metallic nanowires structure

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Science China(Physics,Mechanics & Astronomy) 2012年第10期55卷 1776-1780页

作者： zhu jun LI ZhiQuan College of Electrical Engineering Yanshan UniversityQinhuangdao 066004China

In this work, the terahertz （THz） electromotive force （EMF） of the surface plasmon （SP） electric field and field strength was investigated in its propagation direction. Based on the nanowires structure, we introduced physical models which were light wave energy of surface plasmon polariton （SPP） pulse and the variation of EMF changes in the active condition. Results of theory and verification showed SPP generated EMF with 10-2-10 V among wire radii of 5-30 nm; the electric field was up to 10^5-1066V/cm in the radius of 5 nm; the electric field intensity induced localization at λ=850 nm, and at the same time light intensity amplified 40 times. The characteristics which are femtosecond SPP pulse response and force-field amplifier in this work are significant for nonlinear spectroscopy research.

关键词： nonlinear optical surface plasmon polariton (SPP) THz frequency energy amplification