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SUFFICIENT AND NECESSARY CONDITIONS ON THE EXISTENCE AND ESTIMATES OF BOUNDARY BLOW-UP SOLUTIONS FOR SINGULAR p-LAPLACIAN EQUATIONS
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作者 张学梅 阚士坤 《Acta Mathematica Scientia》 SCIE CSCD 2023年第3期1175-1194,共20页
Let?denote a smooth,bounded domain in R^(N)(N≥2).Suppose that g is a nondecreasing C^(1)positive function and assume that b(x)is continuous and nonnegative inΩ,and that it may be singular on■Ω.In this paper,we pro... Let?denote a smooth,bounded domain in R^(N)(N≥2).Suppose that g is a nondecreasing C^(1)positive function and assume that b(x)is continuous and nonnegative inΩ,and that it may be singular on■Ω.In this paper,we provide sufficient and necessary conditions on the existence of boundary blow-up solutions to the p-Laplacian problem△_(p)u=b(x)g(u)for x∈Ω,u(x)→+∞as dist(x,■Ω)→0.The estimates of such solutions are also investigated.Moreover,when b has strong singularity,the nonexistence of boundary blow-up(radial)solutions and infinitely many radial solutions are also considered. 展开更多
关键词 singular p-Laplacian equation boundary blow-up sub-supersolution method EXISTENCE nonexistence and estimates sufficient and necessary conditions
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Necessary and Sufficient Conditions in Smooth Programming with Generalized Convexity 被引量:1
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作者 孙清滢 叶留青 《Chinese Quarterly Journal of Mathematics》 CSCD 2000年第4期33-37,共5页
Hanson and Mond have grven sets of necessary and sufficient conditions for optimality in constrained optimization by introducing classes of generalized functions, called type Ⅰ functions. Recently, Bector definded un... Hanson and Mond have grven sets of necessary and sufficient conditions for optimality in constrained optimization by introducing classes of generalized functions, called type Ⅰ functions. Recently, Bector definded univex functions, a new class of functions that unifies several concepts of generalized convexity. In this paper, additional conditions are attached to the Kuhn Tucker conditions giving a set of conditions which are both necessary and sufficient for optimality in constrained optimization, under appropriate constraint qualifications. 展开更多
关键词 necessary and sufficient conditions generalized convexity nonlinear programming multiobjective programming type functions
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ON THE NECESSARY AND SUFFICIENT CONDITIONS TO SOLVE A HEAT EQUATION WITH GENERAL ADDITIVE GAUSSIAN NOISE 被引量:2
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作者 Yaozhong HU Yanghui LIU 《Acta Mathematica Scientia》 SCIE CSCD 2019年第3期669-690,共22页
In this note, we consider stochastic heat equation with general additive Gaussian noise. Our aim is to derive some necessary and sufficient conditions on the Gaussian noise in order to solve the corresponding heat equ... In this note, we consider stochastic heat equation with general additive Gaussian noise. Our aim is to derive some necessary and sufficient conditions on the Gaussian noise in order to solve the corresponding heat equation. We investigate this problem invoking two differen t met hods, respectively, based on variance compu tations and on pat h-wise considerations in Besov spaces. We are going to see that, as anticipated, both approaches lead to the same necessary and sufficient condition on the noise. In addition, the path-wise approach brings out regularity results for the solution. 展开更多
关键词 Stochastic heat equation general Gaussian noise L^(2) solution sufficient and necessary condition Wong-Zakai approximation pathwise solution Holder continuity Besov space
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Necessary and Sufficient Conditions for Reactive Azeotropes in Multi-reaction Mixtures in Terms of Elemental Composition 被引量:1
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作者 林金清 李浩然 韩世钧 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2000年第4期361-365,共5页
Necessary and sufficient conditions for azeotropy in reactive mixtures are derived in terms of elemental composition, which shows that in the space of elemental compositions, they take the same functional form as the ... Necessary and sufficient conditions for azeotropy in reactive mixtures are derived in terms of elemental composition, which shows that in the space of elemental compositions, they take the same functional form as the conditions for azeotropy in non-reactive mixtures. The production of methyl tert-butyl ether (MTBE) is taken as an example. It is found that there are a 'pseudo' intermediate-boiling ternary reactive azeotrope at p = 101.325kPa and two 'real' ternary reactive azeotropes at p = 101.325 Pa. The introduced elemental compositions also reduce the dimensionality of the phase diagrams and provide a natural set of variables for visualization of phase behavior. 展开更多
关键词 reactive azeotropy necessary and sufficient condition multi-reactive mixture phase and chemical equilibrium
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NECESSARY AND SUFFICIENT CONDITIONS OF EXISTENCE AND UNIQUENESS OF LIMIT CYCLES FOR A CLASS OF POLYNOMIAL SYSTEM 被引量:1
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作者 刘德明 《Acta Mathematica Scientia》 SCIE CSCD 1991年第1期65-71,共7页
In this paper, we discuss the limit cycles of the systemdx/dt=y·[1+(A(x)]oy/dt=(-x+δy+α_1x^2+α_2xy+α_5x^2y)[1+B(x)] (1)where A(x)=sum form i=1 to n(a_ix~), B(x)=sum form j=1 to m(β_jx^j) and 1+B(x)>0. We ... In this paper, we discuss the limit cycles of the systemdx/dt=y·[1+(A(x)]oy/dt=(-x+δy+α_1x^2+α_2xy+α_5x^2y)[1+B(x)] (1)where A(x)=sum form i=1 to n(a_ix~), B(x)=sum form j=1 to m(β_jx^j) and 1+B(x)>0. We prove that (1) possesses at most one limit cycle and give out the necessary and sufficient conditions of existence and uniqueness of limit cycles. 展开更多
关键词 necessary AND SUFFICIENT conditions OF EXISTENCE AND UNIQUENESS OF LIMIT CYCLES FOR A CLASS OF POLYNOMIAL SYSTEM LIM
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Necessary Optimality Conditions for Multi-Objective Semi-Infinite Variational Problem 被引量:1
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作者 Bharti Sharma Promila Kumar 《American Journal of Operations Research》 2016年第1期36-43,共8页
In this paper, necessary optimality conditions for a class of Semi-infinite Variational Problems are established which are further generalized to a class of Multi-objective Semi-Infinite Variational Problems. These co... In this paper, necessary optimality conditions for a class of Semi-infinite Variational Problems are established which are further generalized to a class of Multi-objective Semi-Infinite Variational Problems. These conditions are responsible for the development of duality theory which is an extremely important feature for any class of problems, but the literature available so far lacks these necessary optimality conditions for the stated problem. A lemma is also proved to find the topological dual of  as it is required to prove the desired result. 展开更多
关键词 SEMI-INFINITE Variational Problem Efficient Solution necessary Optimality conditions
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Necessary Conditions and Situational Variables of Payments for Ecosystem Services
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作者 Pingan Xiang Weiqi Xiang Yu Lu 《Open Journal of Ecology》 2021年第1期1-23,共23页
Clarifying the necessary conditions for the emergence of payments for ecosystem services (PES) and the situational variables that affect PES is the basis for their interpretation, prediction, and selection. This artic... Clarifying the necessary conditions for the emergence of payments for ecosystem services (PES) and the situational variables that affect PES is the basis for their interpretation, prediction, and selection. This article proposes an analytical framework for the emergence of PES and argues that the key to determining whether PES can occur and whether a selected PES program is appropriate is to evaluate the net gain. When payers anticipate that a PES program will provide a satisfactory number of ES and a net gain over the opportunity cost and will cover all costs, it is assumed that the program will be implemented. When it is difficult to accurately evaluate the net gain of PES, the situational variables that affect the costs and benefits need to be examined. The group characteristics, ES characteristics, spatial and temporal contacts between the suppliers and demanders, correlation with private goods and additionality are important situational variables that affect the emergence and choice of PES. 展开更多
关键词 Payments for Ecosystem Services necessary conditions Situational Variable Decision Making
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ON NECESSARY CONDITIONS FOR RESONANCE IN TURNING POINT PROBLEMS FOR ORDINARY DIFFERENTIAL EQUATIONS
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作者 江福汝 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1989年第4期289-296,共8页
In this paper, some misunderstam igs concerning the necessary conditions for resonance for ordinary differential equations with turning point have been corrected, and a recursive process for finding the sequence of ne... In this paper, some misunderstam igs concerning the necessary conditions for resonance for ordinary differential equations with turning point have been corrected, and a recursive process for finding the sequence of necessary conditions for resonance has beenoffered. 展开更多
关键词 ON necessary conditions FOR RESONANCE IN TURNING POINT PROBLEMS FOR ORDINARY DIFFERENTIAL EQUATIONS
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SECOND-ORDER OPTIMALITY CONDITIONS FOR OPTIMAL CONTROL PROBLEMS GOVERNED BY 3-DIMENSIONAL NEVIER-STOKES EQUATIONS 被引量:5
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作者 王丽娟 何培杰 《Acta Mathematica Scientia》 SCIE CSCD 2006年第4期729-734,共6页
This article is concerned with second-order necessary and sufficient optimality conditions for optimal control problems governed by 3-dimensional Navier-Stokes equations. The periodic state constraint is considered.
关键词 necessary and sufficient optimality conditions optimal control Navier-Stokes equation periodic state constraint
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OPTIMALITY CONDITIONS AND DUALITY RESULTS FOR NONSMOOTH VECTOR OPTIMIZATION PROBLEMS WITH THE MULTIPLE INTERVAL-VALUED OBJECTIVE FUNCTION 被引量:4
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作者 Tadeusz ANTCZAK 《Acta Mathematica Scientia》 SCIE CSCD 2017年第4期1133-1150,共18页
In this paper, both Fritz John and Karush-Kuhn-Tucker necessary optimality conditions are established for a (weakly) LU-efficient solution in the considered nonsmooth multiobjective programming problem with the mult... In this paper, both Fritz John and Karush-Kuhn-Tucker necessary optimality conditions are established for a (weakly) LU-efficient solution in the considered nonsmooth multiobjective programming problem with the multiple interval-objective function. Further, the sufficient optimality conditions for a (weakly) LU-efficient solution and several duality results in Mond-Weir sense are proved under assumptions that the functions constituting the considered nondifferentiable multiobjective programming problem with the multiple interval- objective function are convex. 展开更多
关键词 nonsmooth multiobjective programming problem with the multiple interval- objective function Fritz John necessary optimality conditions Karush-Kuhn- Tucker necessary optimality conditions (weakly) LU-efficient solution Mond- Weir duality
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Study on Intention and Forming Conditions of SMT-MG
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作者 SHANG Yuling~1 LI Chunquan~2 1.Dept.of Electronic Engineering,Guilin University of Electronic Technology,Guilin 541004,China 2.Dept.of Electronic Machinery and Traffic Engineering,Guilin University of Electronic Technology,Guilin 541004,China 《武汉理工大学学报》 CAS CSCD 北大核心 2006年第S2期448-452,共5页
Surface Mount Technology Manufacturing Grid (SMT-MG) is the application of the grid technology in the SMT product manufacturing.In this paper,as the new manufacturing mode of SMT product,SMT-MG was brought forward.The... Surface Mount Technology Manufacturing Grid (SMT-MG) is the application of the grid technology in the SMT product manufacturing.In this paper,as the new manufacturing mode of SMT product,SMT-MG was brought forward.Then the concept and intention of the SMT-MG were analyzed.And from the three aspects of sufficient condition,necessary condition and stability condition,the static and dynamic conditions under which the SMT-MG was formed were mainly discuss.Finally,it was proved that the formation and development of SMT-MG is feasible and necessary. 展开更多
关键词 SMT-MG necessary conditION SUFFICIENT conditION
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A NECESSARY AND SUFFICIENT CONDITION FOR THEOSCILLATION OF SOLUTIONS OF LIENARD TYPE SYSTEM WITH MULTIPLE SINGULAR POINTS
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作者 孙继涛 张银萍 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1997年第12期0-0,0-0+0-0,共6页
In this paper, a necessary and sufficient condition for teh solution of Lienard typesystem with muliiple singular points to oscillation under the more general assumptionis given.Results of the papers [1-4] are also ex... In this paper, a necessary and sufficient condition for teh solution of Lienard typesystem with muliiple singular points to oscillation under the more general assumptionis given.Results of the papers [1-4] are also extended and improved in this paper. 展开更多
关键词 Liénard type system oscillating solution necessary and sufficient condition
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The convergence rate and necessary-and-sufficient condition for the consistency of isogeometric collocation method
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作者 LIN Hong-wei XIONG Yun-yang +2 位作者 HU Hui YAN Jia-cong HU Qian-qian 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2022年第2期272-289,共18页
Although the isogeometric collocation(IGA-C)method has been successfully utilized in practical applications due to its simplicity and efficiency,only a little theoretical results have been established on the numerical... Although the isogeometric collocation(IGA-C)method has been successfully utilized in practical applications due to its simplicity and efficiency,only a little theoretical results have been established on the numerical analysis of the IGA-C method.In this paper,we deduce the convergence rate of the consistency of the IGA-C method.Moreover,based on the formula of the convergence rate,the necessary and sufficient condition for the consistency of the IGA-C method is developed.These results advance the numerical analysis of the IGA-C method. 展开更多
关键词 isogeometric collocation CONSISTENCY necessary and sufficient condition convergence rate
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A necessary and sufficient condition for positive solutions of singular fourth order boundary value problems
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作者 YU Xiaoyao PANG Bangyan 《商丘师范学院学报》 CAS 2010年第3期46-53,共8页
This paper deals with the existence of positive solutions for the singular fourth order boundary value problem.A necessary and sufficient condition for the existence of C3 positive solution is given by means of the mo... This paper deals with the existence of positive solutions for the singular fourth order boundary value problem.A necessary and sufficient condition for the existence of C3 positive solution is given by means of the monotone iterative technique.Furthermore,the uniqueness of the C3 positive solution,and the iterative sequence of the C3 positive solution are also obtained. 展开更多
关键词 singular boundary value problem iterative solution necessary and sufficient condition
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Optimality Conditions and Algorithms for Direct Optimizing the Partial Differential Equations
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作者 Victor K. Tolstykh 《Engineering(科研)》 2012年第7期390-393,共4页
New form of necessary conditions for optimality (NCO) is considered. They can be useful for design the direct infinite- dimensional optimization algorithms for systems described by partial differential equations (PDE)... New form of necessary conditions for optimality (NCO) is considered. They can be useful for design the direct infinite- dimensional optimization algorithms for systems described by partial differential equations (PDE). Appropriate algo-rithms for unconstrained minimizing a functional are considered and tested. To construct the algorithms, new form of NCO is used. Such approach demonstrates fast uniform convergence at optimal solution in infinite-dimensional space. 展开更多
关键词 Optimization GRADIENT necessary conditions for OPTIMALITY Partial Differential EQUATIONS Infinite-Dimensional Algorithms
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Some Necessary and Sufficient Condition of Multivariate Random Variable Satisfy Normal Distribution
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作者 伍俊良 秦志仁 《Chinese Quarterly Journal of Mathematics》 CSCD 1996年第1期39-41,共3页
In this paper,we extended some results of article[1],obtain some sufficient and necessary condition which multivariate random variable satisfy normal distribution.
关键词 multivariate random variable normal distribution:sufficient and necessary condition
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A NECESSARY AND SUFFICIENT CONDITION FOR SINGULAR NONLINEAR SECOND-ORDER BOUNDARY VALUE PROBLEMS TO HAVE POSITIVE SOLUTIONS 被引量:1
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作者 ZHAO ZENGQIN 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1998年第1期15-24,共10页
In this paper the following result is obtained: Suppose f(x,u,v) is nonnegative, continuous in ( a, b)×R +×R +; f may be singular at x=a (and/or x=b ) and v=0; f is nondecreasing on u for each x,v,... In this paper the following result is obtained: Suppose f(x,u,v) is nonnegative, continuous in ( a, b)×R +×R +; f may be singular at x=a (and/or x=b ) and v=0; f is nondecreasing on u for each x,v, nonincreasing on v for each x,u; there exists a constant q∈(0,1) such that t qf(x,t -1 u,tu)f(x,u,u)λ qf(x,λ -1 u,λu),0<t<1<λ, u∈R +. Then a necessary and sufficient condition for the equation u″+f(x,u,u)=0 on the boundary condition αu(a)-βu′(a)=0, γ(b)+δu′(b)=0 to have C 1(I) nonzero solutions is that 0<∫ b af(x,e(x),e(x))dx<∞, where α,β,γ,δ are nonnegative real numbers, Δ=(b-a)αγ+αδ+βγ>0, e(x)=G(x,x), G(x,y) is Green's function of above mentioned boundary value problem (when f(x,u,v)≡0). Received September 9,1996. Revised March 31,1997. 1991 MR Subject Classification: 34B. 展开更多
关键词 Second order boundary value problems singular differential equation necessary and sufficient condition.
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制度组态视角下数字生态激发创业活跃度的多元路径——基于NCA与fsQCA的研究 被引量:1
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作者 张吉昌 龙静 王泽民 《研究与发展管理》 北大核心 2024年第2期113-124,共12页
如何优化数字生态环境激发区域创业活跃度是亟待解决的重要管理问题。本文基于制度逻辑理论,采用必要条件分析(NCA)与模糊集定性比较分析(fsQCA)方法,以中国31个省区市为案例,检验了数字政府、数字基础、数字经济、数字能力与数字社会5... 如何优化数字生态环境激发区域创业活跃度是亟待解决的重要管理问题。本文基于制度逻辑理论,采用必要条件分析(NCA)与模糊集定性比较分析(fsQCA)方法,以中国31个省区市为案例,检验了数字政府、数字基础、数字经济、数字能力与数字社会5个条件对区域创业活跃度的组态效应。研究结果表明:数字政府、数字基础、数字经济是区域创业活跃度的必要条件,其重要性程度依次为数字政府、数字基础与数字经济。存在“政府统筹—市场决定型”“政府赋能—市场调节型”“市场调节—社会助力型”“政府统筹—社会助力型”4类产生高创业活跃度的制度组态。存在3类产生非高创业活跃度的制度组态,呈现出以下2个特征:数字生态中各要素均表现不佳;在缺少政府统筹或赋能的情况下,即使市场发挥调节作用,也不能产生高区域创业活跃度。研究揭示了数字生态影响创业活跃度的多元路径,对优化地区数字生态环境,更好激发市场主体创业活力具有重要的实践启示。 展开更多
关键词 数字生态 创业活跃度 制度逻辑 数字经济 NCA fsQCA
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平台型企业商业模式创新组态研究——基于共创生态视角 被引量:3
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作者 郝兴霖 张樨樨 《华东经济管理》 北大核心 2024年第1期37-47,共11页
文章基于共生理论构建了涵盖“共创主体—共创网络—共创环境”的平台型企业商业模式创新前因条件联动模型,并结合NCA和fsQCA方法探讨了多维前因条件与平台型企业商业模式创新的必要性和充分性关系。结果表明:单个前因条件并不构成平台... 文章基于共生理论构建了涵盖“共创主体—共创网络—共创环境”的平台型企业商业模式创新前因条件联动模型,并结合NCA和fsQCA方法探讨了多维前因条件与平台型企业商业模式创新的必要性和充分性关系。结果表明:单个前因条件并不构成平台型企业商业模式创新的必要条件,但强化共创网络结构嵌入能够发挥较为普适的作用;存在“共创精神-生态联动”等3种引发高水平商业模式创新的组态模式,并且高管企业家精神、用户共创参与以及环境动态性存在互补关系;存在4种引发非高水平商业模式创新的组态模式,表明前因条件与商业模式创新之间属于非对称因果关系。研究结论能够为平台型企业商业模式创新提供实践指导,从而促进平台经济的健康发展。 展开更多
关键词 平台型企业 商业模式创新 共生理论 必要条件分析 模糊集定性比较分析
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具有周期系数的线性微分方程的Hyers-Ulam稳定性
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作者 董居悦 谢峰 《数学杂志》 2024年第3期225-235,共11页
本文研究了具有周期系数的一阶和二阶线性微分方程的Hyers-Ulam稳定性.利用常数变易法,获得了其Hyers-Ulam稳定性的充分必要条件,推广了具有周期系数的一阶齐次线性微分方程Hyers-Ulam稳定性的相关结果.
关键词 Ulam型稳定性 线性微分方程 周期系数 充要条件
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