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MULTIPLE POSITIVE SOLUTIONS OF SINGULAR THIRD-ORDER PERIODIC BOUNDARY VALUE PROBLEM 被引量:21
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作者 孙经先 刘衍胜 《Acta Mathematica Scientia》 SCIE CSCD 2005年第1期81-88,共8页
This paper deals with the singular nonlinear third-order periodic boundary value problem u'' + p(3)u = f (t, u), 0 less than or equal to t less than or equal to 2pi, with u((i)) (0) = u((i)) (2pi), i = 0, 1, 2... This paper deals with the singular nonlinear third-order periodic boundary value problem u'' + p(3)u = f (t, u), 0 less than or equal to t less than or equal to 2pi, with u((i)) (0) = u((i)) (2pi), i = 0, 1, 2, where p is an element of (Graphics) and f is singular at t = 0, t = 1 and u = 0. Under suitable weaker conditions than those of [1], it is proved by constructing a special cone in C[0, 2pi] and employing the fixed point index theory that the problem has at least one or at least two positive solutions. 展开更多
关键词 singular boundary value problem third-order differential system positive solution
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委托代理问题中的两种数学方法 被引量:12
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作者 赵文华 席酉民 《管理工程学报》 CSSCI 1999年第2期63-65,68+5,共5页
本文分析了委托代理问题中的两种数学方法(一阶方法和成本收益法)。
关键词 委托人 代理人 代理问题 效用 一阶方法 成本收益法
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一般需求函数下报童模型的定价与库存控制 被引量:14
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作者 张菊亮 章祥荪 王耀球 《系统工程理论与实践》 EI CSCD 北大核心 2008年第9期20-28,共9页
研究单周期联合定价与库存控制问题,即决策者同时决定产品的售价和库存水平.引进了一个新的概念:销售弹性,并利用这一新的概念研究其最优解的性质.对一般需求函数,证明了解的存在性,唯一性,并证明了最优定价是订货量的减函数以及最优订... 研究单周期联合定价与库存控制问题,即决策者同时决定产品的售价和库存水平.引进了一个新的概念:销售弹性,并利用这一新的概念研究其最优解的性质.对一般需求函数,证明了解的存在性,唯一性,并证明了最优定价是订货量的减函数以及最优订货量是定价的减函数.推广了现有的关于单周期联合定价与库存控制问题的结果. 展开更多
关键词 定价 库存 报童模型 订货策略
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遗传算法中排列问题的编码研究 被引量:8
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作者 韩建枫 李敏强 寇纪凇 《计算机工程与应用》 CSCD 北大核心 2002年第12期29-32,共4页
针对排列问题的编码方法一直是遗传算法应用中的重要研究领域。采用各种传统编码方法的编码表示空间通常远远大于实际的问题空间,这不但提高了各算子设计的复杂性,同时很大程度上降低了收敛速度。文章提出了一种针对排列问题基于次序的... 针对排列问题的编码方法一直是遗传算法应用中的重要研究领域。采用各种传统编码方法的编码表示空间通常远远大于实际的问题空间,这不但提高了各算子设计的复杂性,同时很大程度上降低了收敛速度。文章提出了一种针对排列问题基于次序的一维二进制编码方案和两种改良方案,使排列与编码形成了一一映射,最大限度地缩小了编码表示空间与问题空间的差距。采用TSP问题的实验结果表明,文章提出的编码方式具有很好的性能。 展开更多
关键词 遗传算法 排列问题 编码
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环境治理的经济学分析 被引量:12
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作者 王育宝 李国平 《江西财经大学学报》 2003年第6期27-31,共5页
传统理论认为,环境问题的产生根源一是科技因素,二是环境自身的外部性特征。本文主要运用制度经济学、环境经济学等的基本理论和方法在科技条件给定的条件下研究环境问题不能得到根本治理的原因及内在机理,提出必须在既依靠市场机制也... 传统理论认为,环境问题的产生根源一是科技因素,二是环境自身的外部性特征。本文主要运用制度经济学、环境经济学等的基本理论和方法在科技条件给定的条件下研究环境问题不能得到根本治理的原因及内在机理,提出必须在既依靠市场机制也依靠政府干预的前提下,依靠社会力量和非正式制度等制度创新进行环境治理。 展开更多
关键词 环境问题 自然环境 环境污染 市场机制 政府干预 环境治理 中国 市场失灵
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Existence of solutions and positive solutions to a fourth-order two-point BVP with second derivative 被引量:12
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作者 姚庆六 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2004年第3期104-108,共5页
Several existence theorems were established for a nonlinear fourth-order two-point boundary value problem with second derivative by using Leray-Schauder fixed point theorem, equivalent norm and technique on system of ... Several existence theorems were established for a nonlinear fourth-order two-point boundary value problem with second derivative by using Leray-Schauder fixed point theorem, equivalent norm and technique on system of integral equations. The main conditions of our results are local. In other words, the existence of the solution can be determined by considering the height of the nonlinear term on a bounded set. This class of problems usually describes the equilibrium state of an elastic beam which is simply supported at both ends. 展开更多
关键词 Nonlinear fourth-order equation Two-point boundary value problem Solution and positive solution EXISTENCE Fixed point theorem
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明清时期徽州宗族对社会问题的控制 被引量:10
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作者 陈瑞 《中国农史》 CSSCI 北大核心 2007年第4期92-102,共11页
明清时期徽州宗族对社区及族内事务的管理与控制的功能有日益强化的趋势。对宗族社区及族内赌博、溺女、假命图赖、生态环境恶化等社会问题进行积极控制,是这一时期徽州宗族社会自治和社会管理角色扮演的重要体现。徽州宗族积极控制社... 明清时期徽州宗族对社区及族内事务的管理与控制的功能有日益强化的趋势。对宗族社区及族内赌博、溺女、假命图赖、生态环境恶化等社会问题进行积极控制,是这一时期徽州宗族社会自治和社会管理角色扮演的重要体现。徽州宗族积极控制社会问题的主观努力,对于遏制或解决这一时期徽州境内社会问题的恶化和蔓延,从而维持徽州宗族社会秩序的长期稳定与社会的和谐发展起到了一定的积极作用。 展开更多
关键词 徽州宗族 社会问题 社会控制 社会秩序
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Cascadic multigrid methods for parabolic problems 被引量:7
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作者 DU Qiang MING PingBing 《Science China Mathematics》 SCIE 2008年第8期1415-1439,共25页
In this paper,we consider the cascadic multigrid method for a parabolic type equation.Backward Euler approximation in time and linear finite element approximation in space are employed.A stability result is establishe... In this paper,we consider the cascadic multigrid method for a parabolic type equation.Backward Euler approximation in time and linear finite element approximation in space are employed.A stability result is established under some conditions on the smoother.Using new and sharper estimates for the smoothers that reflect the precise dependence on the time step and the spatial mesh parameter,these conditions are verified for a number of popular smoothers.Optimal error bound sare derived for both smooth and non-smooth data.Iteration strategies guaranteeing both the optimal accuracy and the optimal complexity are presented. 展开更多
关键词 cascadic multigrid method parabolic problem finite element methods backward Euler scheme smoother STABILITY optimal error order optimal complexity 65N30 65N55 65F10
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区域旅游安全与国际社会问题 被引量:3
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作者 李柏文 《云南民族大学学报(哲学社会科学版)》 CSSCI 北大核心 2007年第5期99-102,共4页
在旅游全球化和区域旅游一体化活跃背景下,区域旅游安全问题日益凸显。西方人权与安全的悖论,经济诉求与安全诉求的冲突,国际经济格局的不平衡、国际政治秩序的不平等以及区域性民族、宗教和文化冲突是导致区域旅游安全问题凸显的主要... 在旅游全球化和区域旅游一体化活跃背景下,区域旅游安全问题日益凸显。西方人权与安全的悖论,经济诉求与安全诉求的冲突,国际经济格局的不平衡、国际政治秩序的不平等以及区域性民族、宗教和文化冲突是导致区域旅游安全问题凸显的主要社会缘起。区域旅游安全问题是国际社会问题在旅游领域的折射和延伸,要解决区域旅游安全问题必需要从解决国际社会问题入手,方能根除,而不能像过去那样,过分强调旅游业本身的问题和责任。 展开更多
关键词 区域旅游安全 国际社会问题 国际秩序
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Riemann-Hilbert approach and soliton solutions for the Lakshmanan-Porsezian-Daniel equation with nonzero boundary conditions
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作者 Yilin Wang Biao Li 《Communications in Theoretical Physics》 SCIE CAS CSCD 2024年第11期20-32,共13页
We construct the Riemann-Hilbert problem of the Lakshmanan-Porsezian-Daniel equation with nonzero boundary conditions,and use the Laurent expansion and Taylor series expansion to obtain the exact formulas of the solit... We construct the Riemann-Hilbert problem of the Lakshmanan-Porsezian-Daniel equation with nonzero boundary conditions,and use the Laurent expansion and Taylor series expansion to obtain the exact formulas of the soliton solutions in the case of a higher-order pole and multiple higher-order poles.The dynamic behaviors of a simple pole,a second-order pole and a simple pole plus a second-order pole are demonstrated. 展开更多
关键词 Lakshmanan-Porsezian-Daniel equation Riemann-Hilbert problem nonzero boundary conditions multiple higher-order poles
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社会秩序如何可能:试论帕森斯社会秩序理论的逻辑与意义 被引量:4
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作者 吕付华 《甘肃行政学院学报》 2012年第6期76-88,125-126,共13页
在当下我国人文社会科学各学科对社会建设与社会管理进行深入理论思考与讨论的背景下,帕森斯就社会秩序问题进行的理论建构恰为学术界提供了一面宝贵的镜子。因此,以帕森斯的相关著作与论文为依据,本文从分析帕森斯早期的唯意志论行动... 在当下我国人文社会科学各学科对社会建设与社会管理进行深入理论思考与讨论的背景下,帕森斯就社会秩序问题进行的理论建构恰为学术界提供了一面宝贵的镜子。因此,以帕森斯的相关著作与论文为依据,本文从分析帕森斯早期的唯意志论行动理论的理路入手,渐次梳理和阐释了帕森斯在从社会行动迈向行动系统理论时期,社会系统理论成熟期以及交换模型、象征性符号媒介与社会共同体理论晚期围绕着社会秩序问题构建起来的理论逻辑。在此基础上,本文全面而简要地评价了帕森斯社会秩序理论的意义与局限,寄望对帕森斯社会秩序理论的整体、系统研究能够有益于未来的相关研究者。 展开更多
关键词 帕森斯 秩序问题 社会行动系统 交换模型 象征性符号媒介 社会共同体
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Precise integration method for solving singular perturbation problems 被引量:1
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作者 富明慧 张文志 S.V.SHESHENIN 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2010年第11期1463-1472,共10页
This paper presents a precise method for solving singularly perturbed boundary-value problems with the boundary layer at one end. The method divides the interval evenly and gives a set of algebraic equations in a matr... This paper presents a precise method for solving singularly perturbed boundary-value problems with the boundary layer at one end. The method divides the interval evenly and gives a set of algebraic equations in a matrix form by the precise integration relationship of each segment. Substituting the boundary conditions into the algebraic equations, the coefficient matrix can be transformed to the block tridiagonal matrix. Considering the nature of the problem, an efficient reduction method is given for solving singular perturbation problems. Since the precise integration relationship introduces no discrete error in the discrete process, the present method has high precision. Numerical examples show the validity of the present method. 展开更多
关键词 singular perturbation problem first-order ordinary differential equation two-point boundary-value problem precise integration method reduction method
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CONSENSUS OF THE SECOND-ORDER MULTI-AGENT SYSTEMS WITH AN ACTIVE LEADER AND COUPLING TIME DELAY 被引量:2
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作者 郭万里 肖海军 陈士华 《Acta Mathematica Scientia》 SCIE CSCD 2014年第2期453-465,共13页
This article investigates the consensus problem of the second-order multi-agent systems with an active leader and coupling time delay in direct graph. One decentralized state control rule is constructed for each agent... This article investigates the consensus problem of the second-order multi-agent systems with an active leader and coupling time delay in direct graph. One decentralized state control rule is constructed for each agent to track the active leader and it is proved that the proposed control scheme enables the consensus to be obtained when the adjacency topology is fixed/switched. Simulation results show effectiveness of the proposed theoretical analysis. 展开更多
关键词 Consensus problem second-order multi-agent system active leader couplingtime delay
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A New Regularizing Algorithm for Solving the First Kind of Fredholm Integral Equations 被引量:2
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作者 李功胜 刘岩 《Journal of Mathematical Research and Exposition》 CSCD 北大核心 2005年第2期204-210,共7页
Singular value system is applied to construct a new class of improved regularizing methods for solving the first kind of Fredholm integral equations with noisy data. By a priori choosing regularizing parameters, optim... Singular value system is applied to construct a new class of improved regularizing methods for solving the first kind of Fredholm integral equations with noisy data. By a priori choosing regularizing parameters, optimal convergence order of the regularized solution is obtained. And with aids of MATLAB software, numerical results are presented which roughly coincide with the theoretical analysis. 展开更多
关键词 first kind of Predholm integral equation ill-posed problem modified Tikhonov regularization asymptotic order of the regularized solution numerical analysis.
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Optimization Model in Manufacturing Scheduling for the Garment Industry 被引量:2
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作者 Chia-Nan Wang Yu-Chen Wei +2 位作者 Po-Yuk So Viet Tinh Nguyen Phan Nguyen Ky Phuc 《Computers, Materials & Continua》 SCIE EI 2022年第6期5875-5889,共15页
The garment industry in Vietnam is one of the country’s strongest industries in the world.However,the production process still encounters problems regarding scheduling that does not equate to an optimal process.The p... The garment industry in Vietnam is one of the country’s strongest industries in the world.However,the production process still encounters problems regarding scheduling that does not equate to an optimal process.The paper introduces a production scheduling solution that resolves the potential delays and lateness that hinders the production process using integer programming and order allocation with a make-to-order manufacturing viewpoint.A number of constraints were considered in the model and is applied to a real case study of a factory in order to viewhowthe tardiness and latenesswould be affected which resulted in optimizing the scheduling time better.Specifically,the constraints considered were order assignments,production time,and tardiness with an objective function which is to minimize the total cost of delay.The results of the study precisely the overall cost of delay of the orders given to the plant and successfully propose a suitable production schedule that utilizes the most of the plant given.The study has shown promising results that would assist plant and production managers in determining an algorithm that they can apply for their production process. 展开更多
关键词 Production scheduling problem order allocation integer programming make-to-order manufacturing apparel industry
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具有运输次序的运输问题研究 被引量:2
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作者 吴唤群 郭成 《广州大学学报(自然科学版)》 CAS 2008年第5期1-4,共4页
研究了一类新的运输问题———具有运输次序的运输问题,建立了这类运输问题的网络流模型,证明了该模型的有效性,根据解最小费用流问题的思路设计出求解该模型的实用算法,同时通过定义修正权将负权转化为非负权,从而可以用Dijkstra算法... 研究了一类新的运输问题———具有运输次序的运输问题,建立了这类运输问题的网络流模型,证明了该模型的有效性,根据解最小费用流问题的思路设计出求解该模型的实用算法,同时通过定义修正权将负权转化为非负权,从而可以用Dijkstra算法找最短路,使算法得到改进。 展开更多
关键词 运输问题 运输次序 网络流模型 最小费用流 DIJKSTRA算法
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教师课堂问题行为及其预防策略 被引量:2
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作者 李子华 《教育与现代化》 2007年第3期45-50,共6页
教师课堂行为无论是旨在建立课堂秩序,还是为了实现教育目标,都不能违背法律与伦理要求这一前提。然而教师课堂问题行为恰恰背离了这一要求,从而在更一般的意义上引发教育秩序的混乱。避免教师课堂问题行为的发生,需要防止对学生课堂行... 教师课堂行为无论是旨在建立课堂秩序,还是为了实现教育目标,都不能违背法律与伦理要求这一前提。然而教师课堂问题行为恰恰背离了这一要求,从而在更一般的意义上引发教育秩序的混乱。避免教师课堂问题行为的发生,需要防止对学生课堂行为意义的偏差性建构,同时也需要充分认识惩罚在建立课堂秩序方面的限度。 展开更多
关键词 教师 课堂问题行为 教育秩序
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贪婪策略在占线订单加工问题中的竞争分析 被引量:2
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作者 郑斐峰 徐寅峰 《系统管理学报》 北大核心 2007年第4期417-421,共5页
根据实际生产中订单收益随加工长度变化的一般规律,建立了占线订单加工模型,构建一种贪婪策略并分析它在本模型中的竞争性能。具体证明它在中断订单有、无惩罚两种情形下的竞争比,并讨论了模型中收益函数的参数对竞争比结果的影响。
关键词 贪婪策略 占线问题 订单排序 竞争比
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A New Eighth Order Implicit Block Algorithms for the Direct Solution of Second Order Ordinary Differential Equations
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作者 Ademola M. Badmus 《American Journal of Computational Mathematics》 2014年第4期376-386,共11页
This paper focuses on derivation of a uniform order 8 implicit block method for the direct solution of general second order differential equations through continuous coefficients of Linear Multi-step Method (LMM). The... This paper focuses on derivation of a uniform order 8 implicit block method for the direct solution of general second order differential equations through continuous coefficients of Linear Multi-step Method (LMM). The continuous formulation and its first derivatives were evaluated at some selected grid and off grid points to obtain our proposed method. The superiority of the method over the existing methods is established numerically. 展开更多
关键词 UNIFORM order SECOND order Initial Value problem IMPLICIT Block Algorithms ZERO Stable
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α-times Integrated Regularized Cosine Functions and Second Order Abstract Cauchy Problems
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作者 Zhang Jizhou(张寄洲) +1 位作者 Tao Youshan(陶有山) 《Journal of Donghua University(English Edition)》 EI CAS 2001年第1期51-54,共4页
In this paper, α-times integrated C-regularized cosine functions and mild α-times integrated C-existence families of second order are introduced. Equivalences are proved among α-times integrated C-regularized cosin... In this paper, α-times integrated C-regularized cosine functions and mild α-times integrated C-existence families of second order are introduced. Equivalences are proved among α-times integrated C-regularized cosine function for a linear operator A, C-wellposed of (α+1)-times abstract Cauchy problem and mild a -times integrated C-existence family of second order for A when the commutable condition is satisfied. In addition, if A = C-1AC, they are also equivalent to A generating the α -times integrated C-regularized cosine function. The characterization of an exponentially bounded mild α -times integrated C-existence family of second order is given out in terms of a Laplace transform. 展开更多
关键词 a-times integrated regularized cosine function mild a-times integrated C-existence family of second order C-wellposed second order abstract Cauchy problem.
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