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Weak Cartan-type Second Main Theorem for Holomorphic Curves

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Acta Mathematica Sinica,English Series 2008年第3期24卷 455-462页

作者： Qi Ming YAN zhi hua chen Department of Mathematics Tongji University Shanghai 200092 P. R. China

In this paper, a weak Cartan-type second theorem for holomorphic curve f ： C→P^n（C） intersecting hypersurfaces Dj, 1≤j≤q, in P^n（C） in general position with degree dj is given as follows： For every ε〉0, there exists a positive integer M such that ｜｜（q - （n ＋ 1） ε）Tf（r）≤∑j^q=1 1/dj Nf^M（r,Dj）＋o（Tf（r））, where ＂｜｜＂ means the estimate holds for all large r outside a set of finite Lebesgue measure.

关键词： holomorphic curve Nevanlinna Theory second main theorem hypersurface

A review of behavior mechanisms and crowd evacuation animation in emergency exercises

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Journal of Zhejiang University-Science C(Computers and Electronics) 2013年第7期14卷 477-485页

作者： Gao-qi HE Yu YANG zhi-hua chen Chun-hua GU zhi-geng PAN Department of Computer Science and Engineering East China University of Science and Technology Digital Media and Interaction Research Center Hangzhou Normal University

Emergency exercises are an efficient approach for preventing serious damage and harm, including loss of life and property and a wide range of adverse social effects, during various public emergencies. Among various factors affecting the value of emergency exercises, including their design, development, conduct, evaluation, and improvement planning, this paper emphasizes the focal role of evacuees and their behavior. We address two concerns: What are the intrinsic reasons behind human behavior? How do we model and exhibit human behavior? We review studies investigating the mechanisms of psychological behavior and crowd evacuation animation. A comprehensive analysis of logical patterns of behavior and crowd evacuation is presented first. The interactive effects of information (objective and subjective), psychology (panic, small groups, and conflicting roles), and six kinds of behavior contribute to a more effective understanding of an emergency scene and assist in making scientific decisions. Based on these studies, a wide range of perspectives on crowd formation and evacuation animation models is summa- rized. Collision avoidance is underlined as a special topic. Finally, this paper highlights some of the technical challenges and key questions to be addressed by future developments in this rapidly developing field.

关键词： Emergency exercises Behavior mechanisms Crowd evacuation animation Collision avoidance

Trajectory optimization of a deflectable nose missile

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Defence Technology（防务技术） 2017年第3期13卷 158-163页

作者： zhi-yong Zhang Qi-zhong Tang Xiao-hui Sun zhi-hua chen National Key Laboratory of Transient Physics Nanjing University of Science and Technology North China System Engineering Institute

The deflectable nose missile has a longer range by deflecting its nose to improve its aerodynamic *** on detached eddy simulation(DES), the supersonic flow fields of a missile with deflectable nose are simulated numerically and its aerodynamic force coefficients are calculated under the condition of the deflection angles vary from 0° to 8°, angles of attack, 0°-8°, and mach numbers, 2 to 5. Coupling these aerodynamic coefficients with the plumb plane ballistic equations, the extended flight range has been calculated. Furthermore, the genetic algorithm(GA) is employed for the solution of maximum range of the deflected missile.

关键词：偏转角度导弹弹道优化弹头流场数值模拟最大射程动力学特征气动力系数

The influences of wall Lorentz force and field Lorentz force on the cylinder drag reduction

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Acta Mechanica Sinica 2011年第5期27卷 668-674页

作者： Hui Zhang Bao-Chun Fan zhi-hua chen Yan-Ling Li Science and Technology on Transient Physics Laboratory Nanjing University of Science and Technology210094 Nanjing China

In this paper,the effects of Lorentz force on drag reduction for a circular cylinder have been studied experimentally and *** on its effects on drag reduction,the Lorentz force is found to be classified into two parts：one acts directly on the cylinder,named as the wall Lorentz force,and the other called the field Lorentz force acts on the fluid inside the boundary *** wall Lorentz force leads to the generation of a thrust,whereas the field Lorentz force results in drag *** the former dominates the drag variation,the drag would reduce accordingly and even turn into negative （thrust） with the application of Lorentz force.

关键词： Cylinder wake · Flow control · Lorentz force · Electromagnetic control

Preserving global features of fluid animation from a single image using video examples

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Journal of Zhejiang University-Science C(Computers and Electronics) 2012年第7期13卷 510-519页

作者： Yan GUI Li-zhuang MA Chao YIN zhi-hua chen School of Electronic Information and Electrical EngineeringShanghai Jiao Tong UniversityShanghai 200240China Department of Computer Science and Engineering East China University of Science and TechnologyShanghai 200237China

We synthesize animations from a single image by transferring fluid motion of a video example *** a target image of a fluid scene,an alpha matte is required to extract the fluid *** method needs to adjust a user-specified video example for producing the fluid motion suitable for the extracted fluid *** the fluid video database,the flow field of the target image is obtained by warping the optical flow of a video frame that has a visually similar scene to the target image according to their scene correspondences,which assigns fluid orientation and speed *** show that our method is successful in preserving large fluid features in the synthesized *** comparison to existing approaches,it is both possible and useful to utilize our method to create flow animations with higher quality.

关键词： Single image Video example Fluid feature Fluid motion Flow animation

A numerical local orthogonal transform method forstratified waveguides

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Journal of Zhejiang University-Science C(Computers and Electronics) 2010年第12期11卷 998-1008页

作者： Peng LI Wei-zhou ZHONG Guo-sheng LI zhi-hua chen School of Economies and Finance Xi'an Jiaotong University Xi'an 710061 China Department of Mathematics North China University of Water Conservancy and Electric Power Zhengzhou 450045 China Department of Mathematics Zhongyuan University of Technology Zhengzhou 450007 China Science Department Zhijiang College of Zhejiang University of Technology Hangzhou 310027 China

Flattening of the interfaces is necessary in computing wave propagation along strati?ed waveguides in large range step sizes while using marching methods. When the supposition that there exists one horizontal straight line in two adjacent interfaces does not hold, the previously suggested local orthogonal transform method with an analytical formulation is not feasible. This paper presents a numerical coordinate transform and an equation transform to perform the transforms numerically for waveguides without satisfying the supposition. The boundary value problem is then reduced to an initial value problem by one-way reformulation based on the Dirichlet-to-Neumann (DtN) map. This method is applicable in solving long-range wave propagation problems in slowly varying waveguides with a multilayered medium structure.

关键词： Helmholtz equation Local orthogonal transform Dirichlet-to-Neumann (DtN) reformulation Marching method Internal interface

Identification of necroptosis-related lncRNAs for prognosis prediction and screening of potential drugs in patients with colorectal cancer

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World Journal of Gastrointestinal Oncology 2023年第11期15卷 1951-1973页

作者： zhi-hua chen Yi-Lin Lin Shao-Qin chen Xiao-Yu Yang Department of Gastrointestinal Surgery The First Affiliated Hospital of Fujian Medical UniversityFuzhou 350005Fujian ProvinceChina Department of Gastrointestinal Surgery National Regional Medical CenterBinhai Campus of the First Affiliated HospitalFujian Medical UniversityFuzhou 350212Fujian ProvinceChina Peking University People’s Hospital Beijing 100044China School of Basic Medicine Sciences Fujian Medical UniversityFuzhou 350122Fujian ProvinceChina

BACKGROUND Tumor recurrence and metastasis lead to a poor prognosis in colorectal cancer(CRC).Necroptosis is closely related to the tumor microenvironment(TME)and affects tumor recurrence and *** aimed to stratify CRC patients according to necroptosis-related long noncoding RNAs(lncRNAs),which can be used to not only evaluate prognosis and improve precision medicine in clinical practice but also screen potential immunotherapy *** To stratify CRC patients according to necroptosis-related lncRNAs(NRLs),which can be used to not only evaluate prognosis and improve precision medicine in clinical practice but also screen potential immunotherapy *** LncRNA expression profiles were collected from The Cancer Genome *** were identified by coexpression *** regression analysis identified a NRL ***,the value of this signature was comprehensively and multidimensionally evaluated,and its reliability for CRC prognosis prediction was assessed with clinical CRC data and compared with that of six other lncRNA were also performed according to the risk score(RS)of the *** An 8-lncRNA signature significantly associated with overall survival(OS)was constructed,and its reliability was validated with clinical CRC *** of the areas under the receiver operating characteristic curves(AUCs)values for 1-,3-and 5-year OS for this signature were higher than those for the other six lncRNA ***,disease-specific survival and the progression-free interval were all significantly poorer in the high-risk *** RS of the signature showed good concordance with the predicted prognosis,with AUCs for 1-,3-and 5-year OS of 0.79,0.81 and 0.77,***,the calibration plots for this signature combined with clinical factors showed that this combination could effectively improve the ability to predict *** RS was correlated with tumor stage,lymph node metastasis and distant *** of the enriched Kyoto

关键词： Long noncoding RNA Necroptosis Immunotherapy Prognosis Colorectal cancer

Investigation on the flow control of micro-vanes on a supersonic spinning projectile

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Defence Technology（防务技术） 2016年第3期12卷 227-233页

作者： Jie MA zhi-hua chen Zhen-gui huaNG Jian-guo GAO Qiang ZHAO Key Laboratory of Transient Physics Nanjing University of Science and Technology

Studies have shown that micro-wedge vortex generators(MVG)can effectively control the flow separation of supersonic boundary *** order to improve the flight stability of spinning projectile,the original standard 155 mm projectile was taken as an example,and the micro-vanes were mounted at the projectile shoulder to investigate the separation control on the aerodynamic characteristics of *** simulations were performed with the use of DES method for the flow fields of projectiles with and without micro-vanes,and the characteristics of the boundary layer structures and aerodynamic data were compared and *** results show that the micro-vanes can be used to inhibit separation of fluid on projectile surface,and improve the flight stability and firing dispersion of projectile.

关键词： Spinning projectile Micro-vane Stability Aerodynamic characteristics Fluid control

Discrete ellipsoidal statistical BGK model and Burnett equations

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Frontiers of physics 2018年第3期13卷 149-161页

作者： Yu-Dong Zhang Ai-Guo Xu Guang-Cai Zhang zhi-hua chen Pei Wang Key Laboratory of Transient Physics Nanjing University of Science and Technology Nanjing 210094 China Laboratory of Computational Physics Institute of Applied Physics and Computational Mathematics Beijing 100088 China Center for Applied Physics and Technology MOE Key Center for High Energy Density Physics Simulations College of Engineering Peking University Beijing 100871 China

A new discrete Boltzmann model, the discrete ellipsoidal statistical Bhatnagar-Gross-Krook （ES- BGK） model, is proposed to simulate nonequilibrium compressible flows. Compared with the original discrete BGK model, the discrete ES-BGK has a flexible Prandtl number. For the discrete ES-BGK model in the Burnett level, two kinds of discrete velocity model are introduced and the relations between nonequilibrium quantities and the viscous stress and heat flux in the Burnett level are established. The model is verified via four benchmark tests. In addition, a new idea is introduced to recover the actual distribution function through the macroscopic quantities and their space derivatives. The recovery scheme works not only for discrete Boltzmann simulation but also for hydrodynamic ones, for example, those based on the Navier-Stokes or the Burnett equations.

关键词： discrete Boltzmann model eUipsoidal statistical BGK Burnett equations nonequilibriumquantities actual distribution function