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Global Solution of a Nonlinear Conservation Law with Weak Discontinuous Flux in the Half Space
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作者 Xiaoqian Li Jing Zhang 《American Journal of Computational Mathematics》 2018年第4期326-342,共17页
This paper is concerned with the initial-boundary value problem of a nonlinear conservation law in the half space R+= {x |x > 0} where a>0 , u(x,t) is an unknown function of x ∈ R+ and t>0 , u ± , um ar... This paper is concerned with the initial-boundary value problem of a nonlinear conservation law in the half space R+= {x |x > 0} where a>0 , u(x,t) is an unknown function of x ∈ R+ and t>0 , u ± , um are three given constants satisfying um=u+≠u- or um=u-≠u+ , and the flux function f is a given continuous function with a weak discontinuous point ud. The main purpose of our present manuscript is devoted to studying the structure of the global weak entropy solution for the above initial-boundary value problem under the condition of f '-(ud) > f '+(ud). By the characteristic method and the truncation method, we construct the global weak entropy solution of this initial-boundary value problem, and investigate the interaction of elementary waves with the boundary and the boundary behavior of the weak entropy solution. 展开更多
关键词 NONLINEAR Conservation Laws with weak Discontinuous Flux Initial-Boundary Value Problem Shock WAVE RAREFACTION WAVE Contact Discontinuity Interaction Structure of Global weak Entropy solution
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Construction of Global Weak Entropy Solution of Initial-Boundary Value Problem for Scalar Conservation Laws with Weak Discontinuous Flux
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作者 Yihong Dai Jing Zhang 《American Journal of Computational Mathematics》 2017年第4期451-468,共18页
This paper is concerned with the initial-boundary value problem of scalar conservation laws with weak discontinuous flux, whose initial data are a function with two pieces of constant and whose boundary data are a con... This paper is concerned with the initial-boundary value problem of scalar conservation laws with weak discontinuous flux, whose initial data are a function with two pieces of constant and whose boundary data are a constant function. Under the condition that the flux function has a finite number of weak discontinuous points, by using the structure of weak entropy solution of the corresponding initial value problem and the boundary entropy condition developed by Bardos-Leroux-Nedelec, we give a construction method to the global weak entropy solution for this initial-boundary value problem, and by investigating the interaction of elementary waves and the boundary, we clarify the geometric structure and the behavior of boundary for the weak entropy solution. 展开更多
关键词 Scalar Conservation LAWS with weak Discontinuous Flux Initial-Boundary Value Problem ELEMENTARY Wave Interaction Structure of GLOBAL weak Entropy solution
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Exponential Dichotomy and Eberlein-Weak Almost Periodic Solutions 被引量:1
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作者 Elhadi Ait Dads Samir Fatajou Lahcen Lhachimi 《Applied Mathematics》 2012年第9期969-975,共7页
We give sufficient conditions ensuring the existence and uniqueness of an Eberlein-weakly almost periodic solution to the following linear equation dx/dt(t) = A(t)x(t) + f(t) in a Banach space X, where (A(t)) t ∈□ i... We give sufficient conditions ensuring the existence and uniqueness of an Eberlein-weakly almost periodic solution to the following linear equation dx/dt(t) = A(t)x(t) + f(t) in a Banach space X, where (A(t)) t ∈□ is a family of infinitesimal generators such that for all t ∈□, A(t + T) = A(t) for some T > 0, for which the homogeneuous linear equation dx/dt(t) = A(t)x(t) is well posed, stable and has an exponential dichotomy, and f:□ →X is Eberlein-weakly amost periodic. 展开更多
关键词 Bounded solutions ALMOST PERIODIC and Eberlein weak ALMOST PERIODIC Functions Exponential DICHOTOMY Linear Differential Equations
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耐温抗盐聚合物TS-45流变性及驱油效率研究 被引量:8
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作者 欧阳坚 孙广华 +2 位作者 王贵江 朱卓岩 王凤 《油田化学》 CAS CSCD 北大核心 2004年第4期330-332,327,共4页
在45℃(大庆主力油藏温度)下,以超高分子量(2 8×107)HPAM为对比,实验考察了耐温抗盐聚合物TS 45溶液的流变性能和驱油能力。TS 45为丙烯酰胺、强极性(含—SO3H)支链单体及少量疏水缔合单体的共聚物。实验聚合物溶液含盐(NaCl)5g/L... 在45℃(大庆主力油藏温度)下,以超高分子量(2 8×107)HPAM为对比,实验考察了耐温抗盐聚合物TS 45溶液的流变性能和驱油能力。TS 45为丙烯酰胺、强极性(含—SO3H)支链单体及少量疏水缔合单体的共聚物。实验聚合物溶液含盐(NaCl)5g/L,含聚合物1g/L。两种聚合物溶液在0 02~600s-1范围均为假塑性流体,TS 45溶液的粘度大于HPAM溶液。溶液的G′和G″随振荡频率增加(0 1~50Hz)而增大;TS 45的G′(和G″)大于HPAM的相应值;G′和G″曲线的交点,TS 45为0 1Hz,此时G′=G″=0 078Pa,HPAM为0 147Hz,此时G′=G″=0 0088Pa,表明TS 45溶液的弹性大于HPAM溶液。与NaCl浓度1g/L的聚合物溶液相比,实验溶液的G′和G″均下降,在2 81Hz下的保留率对于TS 45分别为48 2%和38 3%,对于HPAM分别为24 1%和17 2%,说明TS 45的耐盐性较好。TS 45在岩心中的阻力系数和残余阻力系数(38 6和9 6)大于HPAM的相应值(25 4和5 7)。在岩心驱油实验中,注入0 38PV聚合物溶液提高采收率的幅度,1g/L的TS 45污水溶液、HPAM清水和污水溶液分别为12 6%、10 5%、8 9%,0 8g/L的TS 45污水溶液为10 7%;在注入量0 2~2 0PV范围内提高采收率的幅度,1g/L的TS 45污水溶液恒大于HPAM污水溶液。图6表2参5。 展开更多
关键词 HPAM NaCl
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ON EXISTENCE OF WEAK SOLUTION TO A KIND OF SEMICONDUCTOR EQUATION AFFECTED BY A MAGNETIC FIELD
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作者 管平 王元明 《Journal of Southeast University(English Edition)》 EI CAS 1991年第2期49-58,共10页
The semiconductor basic equation system under the influence of magneticfield is considered in this paper.The system is a parabolic-elliptic coupled system with themixed initial-boundary value conditions.The existence ... The semiconductor basic equation system under the influence of magneticfield is considered in this paper.The system is a parabolic-elliptic coupled system with themixed initial-boundary value conditions.The existence result of the weak solution to theproblem is obtained by using the regularizing method and Moser’s technique,and the con-ditions proposed by the authors in another paper are then reduced. 展开更多
关键词 coupled system mixed BOUNDARY condition weak solution SEMICONDUCTOR device
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MAJOR-EFFICIENT SOLUTIONS AND WEAKLY MAJOR-EFFICIENT SOLUTIONS OF MULTIOBJECTIVE PROGRAMMING 被引量:12
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作者 HU YUDA(Dept.of Appl.Math.,Shanghai Jiao Tony Univ.,Shanghai 200030) 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1994年第1期85-94,共10页
In this papert the theory of major efficiency for multiobjective programmingis established.The major-efficient solutions and weakly major-efficient solutions of multiobjective programming given here are Pareto efficie... In this papert the theory of major efficiency for multiobjective programmingis established.The major-efficient solutions and weakly major-efficient solutions of multiobjective programming given here are Pareto efficient solutions of the same multiobjectiveprogramming problem, but the converse is not true. In a ceratin sense , these solutionsare in fact better than any other Pareto efficient solutions. Some basic theorems whichcharacterize major-efficient solutions and weakly major-efficient solutions of multiobjective programming are stated and proved. Furthermore,the existence and some geometricproperties of these solutions are studied. 展开更多
关键词 Multiobjective Programming Pareto efficient solution Major-efficientsolution weakly Major-efficient solution.
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GLOBAL WEAK SOLUTIONS FOR AN ATTRACTION-REPULSION CHEMOTAXIS SYSTEM WITH p-LAPLACIAN DIFFUSION AND LOGISTIC SOURCE
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作者 王晓闪 王忠谦 贾哲 《Acta Mathematica Scientia》 SCIE CSCD 2024年第3期909-924,共16页
This paper is concerned with the following attraction-repulsion chemotaxis system with p-Laplacian diffusion and logistic source:■The system here is under a homogenous Neumann boundary condition in a bounded domainΩ... This paper is concerned with the following attraction-repulsion chemotaxis system with p-Laplacian diffusion and logistic source:■The system here is under a homogenous Neumann boundary condition in a bounded domainΩ ■ R^(n)(n≥2),with χ,ξ,α,β,γ,δ,k_(1),k_(2)> 0,p> 2.In addition,the function f is smooth and satisfies that f(s)≤κ-μs~l for all s≥0,with κ ∈ R,μ> 0,l> 1.It is shown that(ⅰ)if l> max{2k_(1),(2k_(1)n)/(2+n)+1/(p-1)},then system possesses a global bounded weak solution and(ⅱ)if k_(2)> max{2k_(1)-1,(2k_(1)n)/(2+n)+(2-p)/(p-1)} with l> 2,then system possesses a global bounded weak solution. 展开更多
关键词 global weak solutions attraction-repulsion P-LAPLACIAN logistic source
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ON VERY WEAK SOLUTIONS OF NONLINEAR ELLIPTIC SYSTEMS
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作者 郑神州 《Journal of Shanghai Jiaotong university(Science)》 EI 1997年第2期8-13,共6页
This paper deals with the improvement of integrability of weak solutions for a class of nonlinear elliptic systems with inhomogeneous items in Sobolev space of the least possible hypotheses. By Hodge decomposition and... This paper deals with the improvement of integrability of weak solutions for a class of nonlinear elliptic systems with inhomogeneous items in Sobolev space of the least possible hypotheses. By Hodge decomposition and weak reverse Hlder inequality it is obtained that every very weak solution of the systems is a classical weak solution. This result extends IwaneicSbordone's and Lewis' conclusion to more general cases. 展开更多
关键词 very weak solutionS Hodge DECOMPOSITION REVERSE Hlder INEQUALITY
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交联聚合物溶液在多孔介质中调驱效果实验研究 被引量:9
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作者 罗宪波 蒲万芬 +1 位作者 武海燕 赵金洲 《油田化学》 CAS CSCD 北大核心 2004年第4期340-342,共3页
用两种非均质填砂模型考察了交联聚合物溶液(LPS)的调驱效果。实验温度60℃;LPS由HPAM(300mg/L)、10%AlCit(37 5mg/L)、稳定剂(55mg/L)、矿化度1×105mg/L、含Ca2+800mg/L、含Mg2+200mg/L的标准盐水配成,在60℃反应3天后使用,粘度为... 用两种非均质填砂模型考察了交联聚合物溶液(LPS)的调驱效果。实验温度60℃;LPS由HPAM(300mg/L)、10%AlCit(37 5mg/L)、稳定剂(55mg/L)、矿化度1×105mg/L、含Ca2+800mg/L、含Mg2+200mg/L的标准盐水配成,在60℃反应3天后使用,粘度为2 35mPa·s(60℃,45s-1)注入量0 5PV;模拟原油60℃粘度12 4mPa·s。并联双岩心组调驱实验结果表明,岩心组渗透率级差较大时(14 9对5 74),进入低渗岩心的LPS比例较大(16%对2%),岩心组采收率提高幅度也较大(28 5%对21 0%)。仿五点井网井组(一注四采)平面非均质模型中渗透率递增的4个区域及全模型的水驱采收率分别为0%、1 77%、11 70%、15 60%及32 62%,注入0 5PVLPS后的采收率提高幅度分别为1 77%、2 34%、4 11%、6 03%及14 25%,即水驱采收率较高的区域注LPS提高采收率的幅度较大。调驱实验显示,LPS既具有深部调剖作用,又具有一定的驱油能力。表2参5。 展开更多
关键词 LPS Mg^2%PLUS%
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Generating Efficient Solutions in Bilevel Multi-Objective Programming Problems
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作者 Calice Olivier Pieume Patrice Marcotte +1 位作者 Laure Pauline Fotso Patrick Siarry 《American Journal of Operations Research》 2013年第2期289-298,共10页
In this paper, we address bilevel multi-objective programming problems (BMPP) in which the decision maker at each level has multiple objective functions conflicting with each other. Given a BMPP, we show how to constr... In this paper, we address bilevel multi-objective programming problems (BMPP) in which the decision maker at each level has multiple objective functions conflicting with each other. Given a BMPP, we show how to construct two artificial multiobjective programming problems such that any point that is efficient for both the two problems is an efficient solution of the BMPP. Some necessary and sufficient conditions for which the obtained result is applicable are provided. A complete procedure of the implementation of an algorithm for generating efficient solutions for the linear case of BMPP is presented. A numerical example is provided to illustrate how the algorithm operates. 展开更多
关键词 MULTI-OBJECTIVE PROGRAMMING Bilevel PROGRAMMING efficient solution efficient EDGE HIERARCHICAL Systems
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ON INTEGRABILITY UP TO THE BOUNDARY OF THE WEAK SOLUTIONS TO A NON-NEWTONIAN FLUID 被引量:2
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作者 Shanshan GUO Zhong TAN 《Acta Mathematica Scientia》 SCIE CSCD 2019年第2期420-428,共9页
This work consider boundary integrability of the weak solutions of a non-Newtonian compressible fluids in a bounded domain in dimension three, which has the constitutive equartions as ■The existence result of weak so... This work consider boundary integrability of the weak solutions of a non-Newtonian compressible fluids in a bounded domain in dimension three, which has the constitutive equartions as ■The existence result of weak solutions can be get based on Galerkin approximation. With the linear operator B constructed by BOGOVSKII, we show that the density ■is square integrable up to the boundary. 展开更多
关键词 COMPRESSIBLE fluid weak solutionS non-Newtonian FLUIDS INTEGRABILITY
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Existence of Entropy Solution for Degenerate Parabolic-Hyperbolic Problem Involving p(x)-Laplacian with Neumann Boundary Condition
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作者 Mohamed Karimou Gazibo Duni Yegbonoma Frédéric Zongo 《Applied Mathematics》 2024年第7期455-463,共9页
We consider a strongly non-linear degenerate parabolic-hyperbolic problem with p(x)-Laplacian diffusion flux function. We propose an entropy formulation and prove the existence of an entropy solution.
关键词 Lebesgue and Sobolev Spaces with Variable Exponent weak solution Entropy solution Degenerate Parabolic-Hyperbolic Equation Conservation Law Leray Lions Type Operator Neumann Boundary Condition Existence Result
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Efficient Solution to Electromagnetic Scattering Problems of Bodies of Revolution by Compressive Sensing 被引量:1
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作者 孔勐 陈明生 +2 位作者 张量 曹欣远 吴先良 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第1期136-139,共4页
Under the theory structure of compressive sensing (CS), an underdetermined equation is deduced for describing the discrete solution of the electromagnetic integral equation of body of revolution (BOR), which will ... Under the theory structure of compressive sensing (CS), an underdetermined equation is deduced for describing the discrete solution of the electromagnetic integral equation of body of revolution (BOR), which will result in a small-scale impedance matrix. In the new linear equation system, the small-scale impedance matrix can be regarded as the measurement matrix in CS, while the excited vector is the measurement of unknown currents. Instead of solving dense full rank matrix equations by the iterative method, with suitable sparse representation, for unknown currents on the surface of BOR, the entire current can be accurately obtained by reconstructed algorithms in CS for small-scale undetermined equations. Numerical results show that the proposed method can greatly improve the computgtional efficiency and can decrease memory consumed. 展开更多
关键词 of in IS on by BOR efficient solution to Electromagnetic Scattering Problems of Bodies of Revolution by Compressive Sensing
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Regularity Criterion of Weak Solutions to the 3D Incompressible Hall-magnetohydrodynamic Equations
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作者 刘坤红 原保全 《Chinese Quarterly Journal of Mathematics》 2015年第3期339-348,共10页
In this paper,we study the regularity criterion of weak solutions to the3 D incompressible Hall-magnetohydrodynamics,which is ifu and Bsatisfy the condition∫_0^T‖_(x3)u(t)‖^q_(LP)+‖▽B‖^γ_(Lβ)dt〈∞ wi... In this paper,we study the regularity criterion of weak solutions to the3 D incompressible Hall-magnetohydrodynamics,which is ifu and Bsatisfy the condition∫_0^T‖_(x3)u(t)‖^q_(LP)+‖▽B‖^γ_(Lβ)dt〈∞ with 3/p+2/q≤1,3/β+2/γ≤1,p〉3,β〉3,then the weak solution(u,B) is a smooth one on(0,T]. 展开更多
关键词 INCOMPRESSIBLE Hallmagnetohydrodynamic equations REGULARITY criterion weak solutions
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ENERGY CONSERVATION FOR THE WEAK SOLUTIONS TO THE 3D COMPRESSIBLE NEMATIC LIQUID CRYSTAL FLOW
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作者 谭忠 李心亮 杨惠 《Acta Mathematica Scientia》 SCIE CSCD 2024年第3期851-864,共14页
In this paper,we establish some regularity conditions on the density and velocity fields to guarantee the energy conservation of the weak solutions for the three-dimensional compressible nematic liquid crystal flow in... In this paper,we establish some regularity conditions on the density and velocity fields to guarantee the energy conservation of the weak solutions for the three-dimensional compressible nematic liquid crystal flow in the periodic domain. 展开更多
关键词 compressible nematic liquid crystal flow weak solutions energy conservation
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Prediction of efficient outputs based on GM(1,N) model and weak DEA efficiency 被引量:2
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作者 Jiefang Wang Sifeng Liu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第6期933-939,共7页
This paper expresses the efficient outputs of decisionmaking unit(DMU) as the sum of "average outputs" forecasted by a GM(1,N) model and "increased outputs" which reflect the difficulty to realize efficient ou... This paper expresses the efficient outputs of decisionmaking unit(DMU) as the sum of "average outputs" forecasted by a GM(1,N) model and "increased outputs" which reflect the difficulty to realize efficient outputs.The increased outputs are solved by linear programming using data envelopment analysis efficiency theories,wherein a new sample is introduced whose inputs are equal to the budget in the issue No.n + 1 and outputs are forecasted by the GM(1,N) model.The shortcoming in the existing methods that the forecasted efficient outputs may be less than the possible actual outputs according to developing trends of input-output rate in the periods of pre-n is overcome.The new prediction method provides decision-makers with more decisionmaking information,and the initial conditions are easy to be given. 展开更多
关键词 efficient outputs GM1 N model data envelopment analysisDEA weak DEA efficiency prediction.
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ε-strongly Efficient Solutions for Vector Optimization with Set-valued Maps 被引量:9
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作者 WANG Qi-liu 《Chinese Quarterly Journal of Mathematics》 CSCD 2010年第1期104-109,共6页
In locally convex Hausdorff topological vector spaces,ε-strongly efficient solutions for vector optimization with set-valued maps are discussed.Firstly,ε-strongly efficient point of set is introduced.Secondly,under ... In locally convex Hausdorff topological vector spaces,ε-strongly efficient solutions for vector optimization with set-valued maps are discussed.Firstly,ε-strongly efficient point of set is introduced.Secondly,under the nearly cone-subconvexlike set-valued maps,the theorem of scalarization for vector optimization is obtained.Finally,optimality conditions of ε-strongly efficient solutions for vector optimization with generalized inequality constraints and equality constraints are obtained. 展开更多
关键词 vector optimization ε-strongly efficient point nearly cone-subconvexlike setvalued maps ε-strongly efficient solutions the theorem of scalarization optimality conditions
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THE EXISTENCE OF A NONTRIVIAL WEAK SOLUTION TO A DOUBLE CRITICAL PROBLEM INVOLVING A FRACTIONAL LAPLACIAN IN R^N WITH A HARDY TERM 被引量:3
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作者 Gongbao LI Tao YANG 《Acta Mathematica Scientia》 SCIE CSCD 2020年第6期1808-1830,共23页
In this paper,we consider the existence of nontrivial weak solutions to a double critical problem involving a fractional Laplacian with a Hardy term:(−Δ)s u−γu|x|2s=|u|2∗s(β)−2 u|x|β+[Iμ∗Fα(⋅,u)](x)fα(x,u),u∈H... In this paper,we consider the existence of nontrivial weak solutions to a double critical problem involving a fractional Laplacian with a Hardy term:(−Δ)s u−γu|x|2s=|u|2∗s(β)−2 u|x|β+[Iμ∗Fα(⋅,u)](x)fα(x,u),u∈H˙s(R n),(0.1)(1)where s∈(0,1),0≤α,β<2s<n,μ∈(0,n),γ<γH,Iμ(x)=|x|−μ,Fα(x,u)=|u(x)|2#μ(α)|x|δμ(α),fα(x,u)=|u(x)|2#μ(α)−2 u(x)|x|δμ(α),2#μ(α)=(1−μ2n)⋅2∗s(α),δμ(α)=(1−μ2n)α,2∗s(α)=2(n−α)n−2s andγH=4 sΓ2(n+2s4)Γ2(n−2s4).We show that problem(0.1)admits at least a weak solution under some conditions.To prove the main result,we develop some useful tools based on a weighted Morrey space.To be precise,we discover the embeddings H˙s(R n)↪L 2∗s(α)(R n,|y|−α)↪L p,n−2s2 p+pr(R n,|y|−pr),(0.2)(2)where s∈(0,1),0<α<2s<n,p∈[1,2∗s(α))and r=α2∗s(α).We also establish an improved Sobolev inequality,(∫R n|u(y)|2∗s(α)|y|αdy)12∗s(α)≤C||u||θH˙s(R n)||u||1−θL p,n−2s2 p+pr(R n,|y|−pr),∀u∈H˙s(R n),(0.3)(3)where s∈(0,1),0<α<2s<n,p∈[1,2∗s(α)),r=α2∗s(α),0<max{22∗s(α),2∗s−12∗s(α)}<θ<1,2∗s=2nn−2s and C=C(n,s,α)>0 is a constant.Inequality(0.3)is a more general form of Theorem 1 in Palatucci,Pisante[1].By using the mountain pass lemma along with(0.2)and(0.3),we obtain a nontrivial weak solution to problem(0.1)in a direct way.It is worth pointing out that(0.2)and 0.3)could be applied to simplify the proof of the existence results in[2]and[3]. 展开更多
关键词 existence of a weak solution fractional Laplacian double critical exponents Hardy term weighted Morrey space improved Sobolev inequality
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试井曲线自动拟合方法研究 被引量:6
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作者 王德山 聂立新 李兆敏 《石油大学学报(自然科学版)》 EI CSCD 北大核心 2005年第2期57-60,64,共5页
利用导数方法对样板曲线进行自动拟合是试井分析中常用的一种方法,但其解释结果不惟一是常见现象。证明了试井曲线自动拟合的一阶或二阶导数方法都是Newton Raphson迭代法,并利用分形理论解释了自动拟合导数法产生多解或无解的原因。针... 利用导数方法对样板曲线进行自动拟合是试井分析中常用的一种方法,但其解释结果不惟一是常见现象。证明了试井曲线自动拟合的一阶或二阶导数方法都是Newton Raphson迭代法,并利用分形理论解释了自动拟合导数法产生多解或无解的原因。针对存在多解的现实,提出了一种利用均匀试验设计表计算多组全局最优解的有效算法,并通过计算实例验证了理论的合理性和算法的有效性。实例计算结果表明,水平井资料的多解现象比直井严重。 展开更多
关键词 线 Newton-Raphson 线
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The Smoothness of Weak Solutions to the System of Second Order Differential Equations with Non-negative Characteristics
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作者 张克农 《Chinese Quarterly Journal of Mathematics》 CSCD 1993年第4期15-22,共8页
In this paper,we will discuss smoothness of weak solutions for the system of second order differential equations eith non-negative characteristies.First of all,we establish boundary,and interior estimates and then we ... In this paper,we will discuss smoothness of weak solutions for the system of second order differential equations eith non-negative characteristies.First of all,we establish boundary,and interior estimates and then we prove that solutions of regularization problem satisfy Lipschitz condition. 展开更多
关键词 diff equa with non-negative characteristics regularization weak solution boundary and interior estimate
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