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Spatio-Temporal Variability of Soil Salinity in Alluvial Plain of the Lower Reaches of the Yellow River——A Case Study

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Pedosphere 2011年第6期21卷 793-801页

作者： LI Kai-Li CHEN Jie tan Man-zhi ZHAO Bing-Zi MI Shu-Xiao SHI xue-Zheng State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 （China） Graduate University of Chinese Academy of Sciences Beijing 100049 （China） Department of Geography Jiangsu Institute of Education Nanjing 210013 （China） School of Water Conservation and Environment Zhengzhou University Zhengzhou 450000 （China）

Soil salinity and hydrologic datasets were assembled to analyze the spatio-temporal variability of salinization in Fengqiu County, Henan Province, China, in the alluvial plain of the lower reaches of the Yellow River. The saline soil and groundwater depth data of the county in 1981 were obtained to serve as a historical reference. Electrical conductivity （EC） of 293 surface soil samples taken from 2 kin x 2 km grids in 2007 and 4{） soil profiles acquired in 2（108 was analyzed and used for comparative mapping. Ordinary kriging was applied to predict EC at unobserved locations to derive the horizontal and vertical distribution patterns and variation of soil salinity. Groundwater table data from 22 observation wells in 2008 were collected and used as input for regression kriging to predict the maximum groundwater depth of the county in 2008. Changes in the groundwater level of Fengqiu County in 27 years from 1981 to 2008 was calculated. Two quantitative criteria, the mean error or bias （ME） and the mean squared error （MSE）, were computed to assess the estimation accuracy of the kriging predictions. The results demonstrated that the soil salinity in the upper soil layers decreased dramatically and the taxonomically defined saline soils were present only in a few micro-landscapes after 27 years. Presently, the soils with relatively elevated salt content were mainly distributed in depressions along the Yellow River bed. The reduction in surface soil salinity corresponded to the locations with deepened maximum groundwater depth. It could be concluded that groundwater table recession allowed water to move deeper into the soil profile, transporting salts with it, and thus played an important role in reducing soil salinity in this region. Accumulation of salts in the soil profiles at various depths below the surface indicated that secondary soil salinization would occur when the groundwater was not controlled at a safe depth.

关键词： electrical conductivity groundwater table kriging salinization salt content

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High-fidelity quantum memory realized via Wigner crystals of polar molecules

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Chinese Physics B 2012年第1期21卷 91-100页

作者： xue Peng Wu Jian-zhi Department of Physics Southeast UniversityNanjing 211189China

The collective excitations of spin states of an ensemble of polar molecules are studied as a candidate for high- fidelity quantum memory. To avoid the collisional properties of the molecules, they are arranged in dipolar crystals under one or two dimensional trapping conditions. We calculate the lifetime of the quantum memory by identifying the dominant decoherence mechanisms and estimating their effects on gate operations when a molecular ensemble qubit is transferred to a microwave cavity.

关键词： polar molecules quantum memory molecular dipolar crystals

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Generalized dominance-based rough set approach to security evaluation with imprecise information

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High Technology Letters 2010年第3期16卷 254-262页

作者： Zhao Liang xue zhi School of Electronic and Electric Engineering Shanghai Jiaotong University Shanghai 200240 P.R. China

The model of grey multi-attribute group decision-making （MAGDM） is studied, in which the attribute values are grey numbers. Based on the generalized dominance-based rough set approach （G-DR- SA）, a synthetic security evaluation method is presented. With-the grey MAGDM security evaluation model as its foundation, the extension of technique for order performance by similarity to ideal solution （TOPSIS） integrates the evaluation of each decision-maker （DM） into a group＇s consensus and obtains the expected evaluation results of information system. Via the quality of sorting （QoS） of G-DRSA, the inherent information hidden in data is uncovered, and the security attribute weight and DMs＇ weight are rationally obtained. Taking the computer networks in a certain university as objects, the example illustrates that this method can effectively remove the bottleneck of the grey MAGDM model and has practical significance in the synthetic security evaluation.

关键词： security evaluation grey number multi-attribute group decision-making (MAGDM) generalized dominance-based rough set approach (G-DRSA)

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Fusion-Riesz frame in Hilbert space

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Applied Mathematics(A Journal of Chinese Universities) 2017年第3期32卷 339-352页

作者： LI xue-bin YANG Shou-zhi Department of Mathematics Shantou University Shantou 515063 China

Fusion-Riesz frame (Riesz frame of subspace) whose all subsets are fusion frame sequences with the same bounds is a special fusion frame. It is also considered a generalization of Riesz frame since it shares some important properties of Riesz frame. In this paper, we show a part of these properties of fusion-Riesz frame and the new results about the stabilities of fusion-Riesz frames under operator perturbation (simple named operator perturbation of fusion-Riesz frames). Moreover, we also compare the operator perturbation of fusion-Riesz frame with that of fusion frame, fusion-Riesz basis (also called Riesz decomposition or Riesz fusion basis) and exact fusion frame.

关键词： fusion-Riesz frame Riesz frame of subspace Riesz frame exact fusion frame

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Some Developments in Nielsen Fixed Point Theory

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Acta Mathematica Sinica,English Series 2018年第1期34卷 91-102页

作者： Bo Ju JIANG xue zhi ZHAO School of Mathematical Sciences Peking University Department of Mathematics Capital Normal University

We give a brief survey of some developments in Nielsen fixed point theory. After a look at early history and a digress to various generalizations, we confine ourselves to several topics on fixed points of self-maps on manifolds and polyhedra. Special attention is paid to connections with geometric group theory and dynamics, as well as some formal approaches.

关键词： Fixed points Nielsen theory

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An Improved F-Expansion Method and Its Application to Coupled Drinfel'd-SokolovWilson Equation

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Communications in Theoretical Physics 2008年第8期50卷 309-314页

作者： ZHAO xue-Qin zhi Hong-Yan Department of Mathematics Qufu Normal University Shandong Rizhao 276826 China Department of Applied Mathematics Dalian University of Technology Dalian 116024 China

With the aid of computerized symbolic computation, an improved F-expansion method is presented to uniformly construct more new exact doubly periodic solutions in terms of rational formal Jscobi elliptic function of nonlinear partial differential equations （NPDFs）. The coupled Drinfel＇d-Sokolov-Wilson equation is chosen to illustrate the method. As a result, we can successfully obtain abundant new doubly periodic solutions without calculating various Jacobi elliptic functions. In the limit cases, the rational solitary wave solutions and trigonometric function solutions are obtained as well.

关键词： Jacobi elliptic function doubly periodic solution rational solitary wave solution

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ON NEWTON-HSS METHODS FOR SYSTEMS OF NONLINEAR EQUATIONS WITH POSITIVE-DEFINITE JACOBIAN MATRICES

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Journal of Computational Mathematics 2010年第2期28卷 235-260页

作者： Zhong-zhi Bai xue-Ping Guo LSEC ICMSEC Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China Department of Mathematics East China Normal University Shanghai 200062 China

The Hermitian and skew-Hermitian splitting （HSS） method is an unconditionally convergent iteration method for solving large sparse non-Hermitian positive definite system of linear equations. By making use of the HSS iteration as the inner solver for the Newton method, we establish a class of Newton-HSS methods for solving large sparse systems of nonlinear equations with positive definite Jacobian matrices at the solution points. For this class of inexact Newton methods, two types of local convergence theorems are proved under proper conditions, and numerical results are given to examine their feasibility and effectiveness. In addition, the advantages of the Newton-HSS methods over the Newton-USOR, the Newton-GMRES and the Newton-GCG methods are shown through solving systems of nonlinear equations arising from the finite difference discretization of a two-dimensional convection-diffusion equation perturbed by a nonlinear term. The numerical implemen- tations also show that as preconditioners for the Newton-GMRES and the Newton-GCG methods the HSS iteration outperforms the USOR iteration in both computing time and iteration step.

关键词： Systems of nonlinear equations HSS iteration method Newton method Local convergence.

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A New General Algebraic Method and Its Application to Shallow Long Wave Approximate Equations

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Communications in Theoretical Physics 2007年第5X期48卷 781-786页

作者： ZHAO xue-Qin zhi Hong-Yan Department of Mathematics Qufu Normal University Rizhao 276826 China Department of Applied Mathematics Dalian University of Technology Dalian 116024 China

A new general algebraic method is presented to uniformly construct a series of exact solutions for nonlinear evolution equations （NLEEs）. For illustration, we apply the new method to shallow long wave approximate equations and successfully obtain abundant new exact solutions, which include rational solitary wave solutions and rational triangular periodic wave solutions. The method is straightforward and concise, and it can also be applied to other nonlinear evolution equations in mathematical physics.

关键词： new general algebraic method nonlinear evolution equations solitary wave solutions

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Sequential intraventricular injection of tigecycline and polymyxin B in the treatment of intracranial Acinetobacter baumannii infection after trauma: a case report and review of the literature

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Military Medical Research 2020年第4期7卷 497-502页

作者： Li Zhong xue-zhi Shi Lei Su zhi-Feng Liu Second Clinical College of Guangzhou University of Chinese Medicine Guangzhou 510515China Department of Critical Care Medicine the First Affiliated Hospital of Guizhou University of Chinese MedicineGuiyang 550001China Department of Critical Care Medicine General Hospital of Southern Theater Command of PLAGuangzhou 510010China Key Laboratory of Hot Zone Trauma Care and Tissue Repair of PLA General Hospital of Southern Theater Command of PLAGuangzhou 510010China

Background:Intracranial infection after craniotomy is one of the most serious postoperative complications,especially multidrug-resistant(MDR)or extensively drug-resistant(XDR)bacterial meningitis,and strongly affects the prognosis of *** treatment experience regarding these infections is *** presentation:We report a case of severe intracranial infection of XDR Acinetobacter baumannii(***)that was treated by intravenous(IV)injection,sequential intraventricular(IVT)injection of tigecycline and polymyxin B,and other anti-infective *** results were obtained,and the patient was eventually discharged from the *** case is characterized by intracranial ***:The polymyxin B IV+IVT pathway is an ideal treatment strategy for XDR *** tigecycline IVT pathway is also a safe treatment option.

关键词： Intraventricular injection of tigecycline Polymyxin B Intracranial infection Acinetobacter baumannii

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Mixtures of Semiparametric Varying Coefficient Models for Longitudinal Data with Nonignorable Dropout

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Acta Mathematicae Applicatae Sinica 2010年第1期26卷 125-132页

作者： zhi-qiang Li Liu-gen xue College of Sciences Beijing University of Chemical Technology Beijing 100029 China College of Applied Sciences Beijing University of Technology Beijing 100022 China

Informative dropout often arise in longitudinal data. In this paper we propose a mixture model in which the responses follow a semiparametric varying coefficient random effects model and some of the regression coefficients depend on the dropout time in a non-parametric way. The local linear version of the profile-kernel method is used to estimate the parameters of the model. The proposed estimators are shown to be consistent and asymptotically normal, and the finite performance of the estimators is evaluated by numerical simulation.

关键词： Nonignorable dropout, Estimating equation, Profile-kernel, Local linear estimation, Longitudinal data Semiparametric varying coefficient

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