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Study on fuzzy method applied in classified groundwater environmental vulnerability degree
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《Global Geology》 1998年第1期82-82,共1页
关键词 Study on fuzzy method applied in classified groundwater environmental vulnerability degree
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Comprehensive Evaluation on the Level of Agricultural Modernization in Eastern China 被引量:1
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作者 MEN Ke-pei TANG Sha-sha 《Asian Agricultural Research》 2010年第2期45-48,共4页
Based on correct understanding of the connotation and essence of agricultural modernization,according to the data in 2008 China Statistical Yearbook and the relevant literatures about eastern China,a total of 12 indic... Based on correct understanding of the connotation and essence of agricultural modernization,according to the data in 2008 China Statistical Yearbook and the relevant literatures about eastern China,a total of 12 indices are selected to construct the evaluation index system of agricultural modernization in eastern China by combining with its social development and following the principles of systematization,comprehensiveness,representativeness,legitimacy and comparability.Then,according to the decision-making rules of modern science,3 alternatives are put forward and max compatibility degree method is used to generate the optimization solution.Result shows that agricultural modernization in eastern China can be classified into three types.The first type is Shanghai;the second type includes Zhejiang,Jiangsu,Fujian and Shandong;and the third type is Jiangxi and Anhui.The evaluation result is in accord with the actual situation of agricultural development in eastern China.Finally,since there still needs improvement in capital investment,rural education,agricultural science and technology research,peasant training,and social and organizational structure,it is pointed out that we should optimize the investment agriculture,enhance support for science and technology,perfect the mechanism of "promoting agriculture development by industry and developing the township by the city",and accelerate the development of agricultural modernization in eastern China. 展开更多
关键词 Agricultural modernization Entropy method TOPSIS method Max compatibility degree method China
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Existence of Solutions for a Four-point Boundary Value Problem with a p(t)-Laplacian
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作者 LI YUAN-XIAO GAO WEN-JIE SONG WEN-JING 《Communications in Mathematical Research》 CSCD 2015年第1期23-30,共8页
This paper deals with the existence of solutions to the p(t)-Laplacian equation with four-point boundary conditions. It is shown, by Leray-Schauder fixed point theorem and degree method, that under suitable conditio... This paper deals with the existence of solutions to the p(t)-Laplacian equation with four-point boundary conditions. It is shown, by Leray-Schauder fixed point theorem and degree method, that under suitable conditions, solutions of the problem exist. The interesting point is that p(t) is a general function. 展开更多
关键词 p(t)-Laplacian four-point boundary condition fixed point theorem Leray-Schauder degree method
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Existence of Weak Solution for p(x)-Kirchhoff Type Problem Involving the p(x)-Laplacian-like Operator by Topological Degree
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作者 EL OUAARABI Mohamed ALLALOU Chakir MELLIANI Said 《Journal of Partial Differential Equations》 CSCD 2023年第2期203-219,共17页
In this paper,we study the existence of"weak solution"for a class of p(x)-Kirchhoff type problem involving the p(x)-Laplacian-like operator depending on two real parameters with Neumann boundary condition.Us... In this paper,we study the existence of"weak solution"for a class of p(x)-Kirchhoff type problem involving the p(x)-Laplacian-like operator depending on two real parameters with Neumann boundary condition.Using a topological degree for a class of demicontinuous operator of generalized(S_(+))type and the theory of the variable exponent Sobolev space,we establish the existence of"weak solution"of this problem. 展开更多
关键词 p(x)-Kirchhoff type problem p(x)-Laplacian-like operator weak solution topological degree methods variable exponent Sobolev space
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Reverse triple Ⅰ method of fuzzy reasoning 被引量:4
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作者 宋士吉 吴澄 《Science in China(Series F)》 EI 2002年第5期344-364,共21页
A theory of reverse triple I method with sustention degree is presented by using the implication operator R0 in every step of the fuzzy reasoning. Its computation formulas of supremum for fuzzy modus ponens and infimu... A theory of reverse triple I method with sustention degree is presented by using the implication operator R0 in every step of the fuzzy reasoning. Its computation formulas of supremum for fuzzy modus ponens and infimum for fuzzy modus tollens are given respectively. Moreover, through the generalization of this problem, the corresponding formulas of α-reverse triple I method with sustention degree are also obtained. In addition, the theory of reverse triple I method with restriction degree is proposed as well by using the operator R0, and the computation formulas of infimum for fuzzy modus ponens and supremum for fuzzy modus tollens are shown. 展开更多
关键词 fuzzy reasoning implication operator R0 reverse triple I method with sustention degree reverse triple I method with restriction degree.
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Sensitivity Analysis of the Hydrodynamic Coefficients in 4 Degrees of Freedom Ship Manoeuvring Mathematical Model 被引量:2
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作者 王雪刚 邹早建 +1 位作者 杨昭龙 徐锋 《Journal of Shanghai Jiaotong university(Science)》 EI 2015年第5期584-590,共7页
The S-type test is simulated based on a ship manoeuvring mathematical model of 4 degrees of freedom(4-DOF);simultaneously,sensitivity analysis of the hydrodynamic coefficients in the mathematical model is implemented ... The S-type test is simulated based on a ship manoeuvring mathematical model of 4 degrees of freedom(4-DOF);simultaneously,sensitivity analysis of the hydrodynamic coefficients in the mathematical model is implemented by using an indirect method.The mathematical model is simplified by omitting the coefficients of smaller sensitivity according to the results of sensitivity analysis.The 10°/10° zigzag test and 35° turning circle manoeuvre are simulated with the original and the simplified mathematical models.The comparison of the simulation results shows the effectiveness of the sensitivity analysis and the validity of the simplified model. 展开更多
关键词 ship manoeuvring hydrodynamic coefficients sensitivity analysis indirect method 4 degrees of freedom(4-DOF)
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Affine-periodic solutions by averaging methods 被引量:1
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作者 Jiamin Xing Xue Yang Yong Li 《Science China Mathematics》 SCIE CSCD 2018年第3期439-452,共14页
This paper concerns the existence of affine-periodic solutions for perturbed affine-periodic systems.This kind of affine-periodic solutions has the form of x(t+T)≡Qx(t) with some nonsingular matrix Q,which may be qua... This paper concerns the existence of affine-periodic solutions for perturbed affine-periodic systems.This kind of affine-periodic solutions has the form of x(t+T)≡Qx(t) with some nonsingular matrix Q,which may be quasi-periodic when Q is an orthogonal matrix. It can be even unbounded but x(t)/|x(t)| is quasi-periodic,like a helical line. for example x(t)=e^(at)(cos ωt, sin ωt), when Q is not an orthogonal matrix. The averaging method of higher order for finding affine-periodic solutions is given by topological degree. 展开更多
关键词 affine-periodic solutions averaging method topological degree
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Non-constant Stationary Solutions to a Prey-predator Model with Diffusion
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作者 Ming Yang Wen-yan Chen 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2009年第1期141-150,共10页
In this paper, a nonlinear predator reproduction and prey competition model with diffusion is discussed. Some existence and non-existence results concerning non-constant positive steady-states are presented using topo... In this paper, a nonlinear predator reproduction and prey competition model with diffusion is discussed. Some existence and non-existence results concerning non-constant positive steady-states are presented using topological degree argument and the energy method, respectively. 展开更多
关键词 Prey-predator model steady states degree method energy method
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m-POINT BOUNDARY VALUE PROBLEM FOR SECOND ORDER IMPULSIVE DIFFERENTIAL EQUATION AT RESONANCE
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作者 Guolan Cai Dept.of Math.,Minzu University of China,Beijing 100081 《Annals of Differential Equations》 2012年第4期379-384,共6页
In his paper,we obtain a general theorem concerning the existence of solutions to an m-point boundary value problem for the second-order differential equation with impulses.Moreover,the result can also be applied to s... In his paper,we obtain a general theorem concerning the existence of solutions to an m-point boundary value problem for the second-order differential equation with impulses.Moreover,the result can also be applied to study the usual m-point boundary value problem at resonance without impulses. 展开更多
关键词 impulsive differential equation m-point boundary value problem coincidence degree method resonance case
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Solvability of Elliptic Boundary Value Problems without Standard Landesman-Lazer Condition 被引量:1
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作者 Zhiqing Han Department of Applied Mathematics.Dalian University of Technology,Dalian 116024,P.R.China 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2000年第2期349-359,共11页
In this paper we prove a very general result concerning solvability of the resonant problem: Δu+λ<sub>k</sub>u+g(x, u)=h(x);u=0, xΩ, which immediately gives three generalized Landesman-Lazer conditi... In this paper we prove a very general result concerning solvability of the resonant problem: Δu+λ<sub>k</sub>u+g(x, u)=h(x);u=0, xΩ, which immediately gives three generalized Landesman-Lazer conditions. The most interesting application of the general result is concerned with the problem when λ<sub>k</sub>=λ<sub>1</sub>. in which case we prove solvability results for it under conditions which are not the standard Landesman-Lazer condition or only partly enjoy it. Furthermore, we propose a new sign condition and give a comprehensive extension of a main result of Figueiredo and Ni. 展开更多
关键词 Elliptic boundary value problems Leray-Schauder degree continuation method Landesman-Lazer condition Semi-Landesman-Lazer conditions Sign condition
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Effect of low temperature in the development cycle of Lucilia sericata (Meigen) (Diptera, Calliphoridae): implications for the minimum postmortem interval estimation 被引量:2
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作者 Laetitia Cervantès Laurent Dourel +2 位作者 Emmanuel Gaudry Thierry Pasquerault Benoit Vincent 《Forensic Sciences Research》 2018年第1期52-59,共8页
Knowledge of necrophagous insects' developmental data is necessary for the forensic entomologist to estimate a reliable minimum postmortem interval (PMImin).Among the most represented necrophagous species,Lucilia ... Knowledge of necrophagous insects' developmental data is necessary for the forensic entomologist to estimate a reliable minimum postmortem interval (PMImin).Among the most represented necrophagous species,Lucilia sericata (Diptera,Calliphoridae) is particularly interesting.It is regularly identified in samples,with a predominance in summer,and is commonly used by analysts of our entomology department (Institut de Recherche Criminelle de la Gendarmerie Nationale) to estimate the PMImin with the accumulated degree days (ADD) method.This method requires the mathematical lower thermal threshold to be known.This value dictates the quality of the applied ADD method but cannot be considered as fixed,especially when insect development occurs at temperatures close to the biological threshold.In such conditions,it is necessary to study the influence of such temperatures on development rate,as well as the consequences of estimating the period of first oviposition on cadavers,when using the ADD method.Seven replicate rearings were conducted at six different temperatures: 30 ℃,24 ℃,18 ℃,15 ℃,12 ℃ and 10 ℃.Time of development and time of emergence were recorded.The effect of low temperature on the development cycle and the reliability of the ADD method under this entire temperature spectrum were studied using different linear regression models.Calculated durations of total insect time development and experimental rearing duration were then compared.A global linear model cannot be used on the whole temperature spectrum experienced by L.sericata without resulting in an overestimation at some temperatures.We found a combination of two linear regression models to be suitable for the estimation of the total development time,depending on the temperature experienced by L.sericata.This approach allowed us to obtain a variation lower than 2% at 12 ℃ and 10 ℃ between the calculated duration and experimental duration of development.In comparison,the results obtained with a global model show a variation higher than 3% at 12 ℃ and 10%at 10℃. 展开更多
关键词 Forensic science forensic entomology accumulated degree days(ADD)method minimum PMI low temperature
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