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Practice of precision surgery in primary liver cancer

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Hepatobiliary & Pancreatic Diseases International 2021年第2期20卷 108-109页

作者： Yun Hu zhen-hua Shen Department of Pathology Huzhou Traditional Chinese Medicine Hospital Affiliated to Zhejiang Chinese Medical UniversityHuzhou 313000China Department of General Surgery Huzhou Central HospitalHuzhou 313003China

Primary liver cancer(PLC)is mainly composed of three major cancer:intrahepatic cholangiocarcinoma,hepatocellular carcinoma and mixed hepatocellular-cholangiocellular *** is the sixth most common cancer and the second ... 详细信息

关键词： cancer carcinoma. liver

Fixed-node Quantum Monte Carlo: A Novel Approach

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Chinese Chemical Letters 2002年第1期13卷 55-58页

作者： Hong Xin huaNG zhen hua ZHAO Department of Chemistry Hunan Normal UniversityChangsha 410081

In this paper, a novel method for fixed-node quantum Monte Carlo is given. We have derived an expansion of the eigenvalue of the energy for a system and proved that the value of the energy calculated using the traditional fixed-node quantum Monte Carlo method is only the zero order approximation of the eigenvalue of the energy. But when using our novel method, in the case of only increasing less computing amounts (<1%), we can obtain conveniently the first order approximation, second order approximation, and so on. We have calculated the values of the zero, first and second approximation (0, 1 and 2) of the energies of 11A1 state of CH2, 1Ag (C4h, acet) state of C8 and the ground-state of H2O using this novel method. The results indicate that for 11A1 state of CH2, 1Ag (C4h, acet) state of C8 and the ground-state of H2O it needs only the second order approximation to obtain electronic correlation energy with over 97%. This demonstrates that this novel method is very excellent in both the computing accuracy and the amount of calculation required.

关键词： Fixed-node quantum Monte Carlo method electronic correlation energy.

On Equilibrium in a Constant Retrial Queuing System with Reserved Time and Vacations

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Journal of the Operations Research Society of China 2022年第4期10卷 785-800页

作者： Lin-Lin Wang Li-Wei Liu Xu-Dong chai zhen Wang School of Science Nanjing University of Science and TechnologyNanjing210094China

This paper investigates an M/M/1 constant retrial queue with reserved time and vacations.A new arriving customer will take up the server and accept service immediately if the server is ***,if the server is busy or on vacation,customers have to join a retrial orbit and wait for *** a service is completed,the server will reserve a random time to seek a customer from the orbit at a constant retrial *** there is no arrivals(from the orbit or outside)during the idle period,to save energy,the server will take a *** paper studies the fully unobservable ***,the steady-state condition of the system is analyzed by using the Foster’s criterion,and the customers’expected waiting time is obtained based on the generating function *** then,by introducing an appropriate revenue structure,the equilibrium strategies of customers and the socially optimal strategy are all ***,a comparison between them is made and the effect of some main system parameters is studied.

关键词： Queuing Unobservable Equilibrium strategies Reserved time Vacation Retry

Theoretical and experimental investigations on an X-shaped vibration isolator with active controlled variable stiffness

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Applied Mathematics and Mechanics(English Edition) 2024年第8期45卷 1371-1386页

作者： Zeyu chai J.T.HAN Xuyuan SONG Jian ZANG Yewei ZHANG zhen ZHANG College of Aerospace Engineering Shenyang Aerospace UniversityShenyang 110136China Jacobs School of Engineering University of California San DiegoSan Diego CA 92122U.S.A. Key Laboratory of Vibration and Control of Aero-Propulsion System Ministry of EducationNortheastern UniversityShenyang 110819China

A novel X-shaped variable stiffness vibration isolator(X-VSVI)is *** Runge-Kutta method,harmonic balance method,and wavelet transform spectra are introduced to evaluate the performance of the X-VSVI under various *** layer number,the installation angle of the X-shaped structure,the stiffness,and the active control parameters are systematically *** addition,a prototype of the X-VSVI is manufactured,and vibration tests are carried *** results show that the proposed X-VSVI has a superior adaptability to that of a traditional X-shaped mechanism,and shows excellent vibration isolation performance in response to different amplitudes and forms of ***,the vibration isolation efficiency of the device can be improved by appropriate adjustment of parameters.

关键词： bionic vibration isolation X-shaped structure variable stiffness structure nonlinear dynamics prototype experiment

Some Special Types of Multisoliton Solutions of the Modified Kadomtsev-Petviashvili Equation

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Communications in Theoretical Physics 2003年第3X期40卷 262-264页

作者： huaNGWen-hua YUDang-Jun JINMei-zhen InstituteofNonlinearPhysics ZhejiangNormalUniversityJinhua321004China CollegeofJinhuaProfessionalTechnology Jinhua321007China CollegeofEducationScienceandTechnology ZhejiangNormalUniversityJinhua321004China

Using the standard truncated Painlevé analysis approach, we have obtained some new special types of multisoliton solutions of a (2+ 1)-dimensionM integrable model, the modified Kadomtsev-Petviashvili (mKP) equation.

关键词：改进Kadomtsev-Petviashvili方程多孤波解 (2+1)维积分模型非线性演化方程

Investment in deepwater oil and gas exploration projects:a multi-factor analysis with a real options model

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Petroleum Science 2015年第3期12卷 525-533页

作者： Xin-hua Qiu zhen Wang Qing Xue School of Business Administration China University of Petroleum Academy of Chinese Energy Strategy China University of Petroleum

Deepwater oil and gas projects embody high risks from geology and engineering aspects, which exert substantial influence on project valuation. But the uncer- tainties may be converted to additional value to the projects in the case of flexible management. Given the flexibility of project management, this paper extends the classical real options model to a multi-factor model which contains oil price, geology, and engineering uncertainties. It then gives an application example of the new model to evaluate deepwater oil and gas projects with a numerical analytical method. Compared with other methods and models, this multi-factor real options model contains more project information. It reflects the potential value deriving not only from oil price variation but also from geology and engi- neering uncertainties, which provides more accurate and reliable valuation information for decision makers.

关键词： Investment decision - Real options Multi-factor model Option pricing - Deepwater oil and gas

Differences in major ions as well as hydrogen and oxygen isotopes of sediment pore water and lake water

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Water Science and Engineering 2018年第2期11卷 147-156页

作者： Zhuo Zhang hua-ming Guo zhen Wang State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences MOE Key Laboratory of Groundwater Circulation & Environment Evolution China University of Geosciences School of Water Resources and Environment China University of Geosciences

Isotopic and chemical compositions of pore water(PW) are highly relevant to environmental and forensic study. Five lake water(LW)samples and five sediment samples were collected to investigate the effects of pore sizes of sediments on PW chemistry and stable isotopes and determine mechanisms controlling their variations. Six pore water fractions were extracted from different-sized pores in each sediment sample at six sequential centrifugal speeds for chemical and isotopic analysis. The sediments consisted mainly of quartz, feldspar, and clay minerals. The hydrogen and oxygen isotopic compositions of PW are mainly controlled by the overlying LW, although the lag effect of exchange between overlying LW and PW results in isotopic differences when recharge of LW is quicker than isotopic exchange in PW. Identical isotopic compositions of PW from sediments with different pore sizes indicate that isotopic exchange of water molecules with different pore sizes is a quick process. The ratio of average total dissolved solid(TDS) concentration of PW to TDS concentration of LW shows a strong relationship with adsorption capacity of sediments, demonstrating that remobilization of ions bound to sediments mainly causes a chemical shift from LW to *** of Ca^(2+), Mg^(2+),and Cl^-in PW remain unchanged,while concentrations of Na^+,K^+,and SO_4^(2-) slightly increase with decreasing pore size. Chemical differences of PW from sediments with different pore sizes are governed by ion adsorption properties and surface characteristics of different-si zed particles.

关键词： Pore size Centrifugal extraction Hydrogen and oxygen isotopes Major ions Remobilization

Global Solutions of the Evolutionary Faddeev Model with Small Initial Data

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Acta Mathematica Sinica,English Series 2011年第2期27卷 309-328页

作者： zhen LEI Fang hua LIN Yi ZHOU School of Mathematical Sciences LMNS and Shanghai Key Laboratory for Contemporary Applied Mathematics Fudan University Shanghai 200433 P. R. China Courant Institute of Mathematics New York University NY 10012 USA

We consider the Cauchy problem for evolutionary Faddeev model corresponding to maps from the Minkowski space R^1＋n to the unit sphere S2, which obey a system of non-linear wave equations. The nonlinearity enjoys the null structure and contains semi-linear terms, quasi-linear terms and unknowns themselves. We prove that the Cauchy problem is globally well-posed for sufficiently small initial data in Sobolev space.

关键词： Faddeev model global existence quasi-linear wave equations semi-linear wave equations

Nonlocal Symmetries and Conservation Laws of Nonlocal Camassa-Holm Type Equations

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Acta Mathematicae Applicatae Sinica 2015年第4期31卷 909-920页

作者： zhen-hua SHI Jing KANG Lu YAN Department of Mathematics Northwest University Center for Nonlinear Studies Northwest University Xingzhi College Xi'an University of Finance and Economics

The two-component μ-Camassa-Holm equation, the μ-Camassa-Holm equation and the modified μ- Camassa-Holm equation are three nonlocal integrable models. In this paper, it is shown that the two-component μ-Camassa-Holm equation and the μ-Camassa-Holm equation with a linear dispersion admit a kind of nonlocal symmetries, and the modified μ-Camassa-Holm equation does not have such kind of nonlocal symmetry. An number of conservation laws to the modified μ-Camassa-Holm equation and μ-Camassa-Holm equation are obtained.

关键词： Nonlocal symmetry conservation law the two-component μ-Camassa-Holm equation the modi-fied μ-Camassa-Holm equation the μ-Camassa-Holm equation