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利用Green函数求解二阶线性非齐次微分方程
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作者 王治国 《高等数学研究》 2025年第4期122-125,共4页
针对二阶线性非齐次微分方程的初值问题,边值问题,半无界问题和全空间问题,介绍了Green函数的求解方法,实例说明了该方法的应用.
关键词 二阶线性微分方程 green函数 STURM-LIOUVILLE问题
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Analysis of problems in urban green space system planning in China 被引量:16
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作者 WANG Xiao-Jun 《Journal of Forestry Research》 SCIE EI CAS CSCD 2009年第1期79-82,共4页
This paper discusses the major problems in urban green space system (UGSS) planning at both general and special planning levels in China. At general planning level, the problems of the UGSS are mainly from the ignor... This paper discusses the major problems in urban green space system (UGSS) planning at both general and special planning levels in China. At general planning level, the problems of the UGSS are mainly from the ignorance in the characteristics of urban nature spaces and the limitation factors of the urban planning system. Great importance is attached to the green spaces in the built area of city, but the green spaces in surrounding areas of the city is unnoticed. Furthermore, because the area of UGSS planning is strictly limited by the administrative zoning, the green space system loses its integrity and rationality in spatial patterns. The schedules of urban development planning mismatched the paces and progresses of the ecological restoration cycles. At special plan level, the problem of the UGSS in China is that the green spaces quantity was over emphasized but the rationality of their layouts is neglected.. Meanwhile, the requirement of the spatial structures and the green spaces layouts to balance between the urban development and the natural ecological environments is often ignored. With regard to the layouts in the UGSS planning practices, the existing problems are the compromising to the existing land-uses, the 'filling in' approach to plan green spaces and an over-emphasis on the layout patterns. 展开更多
关键词 Urban green Space System (UGSS) PLANNING problemS quantity layout
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Problems and Countermeasures of Green Logistics Development in China 被引量:3
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作者 Li Hongxin Qu Qunzhen 《Meteorological and Environmental Research》 CAS 2014年第6期44-46,共3页
Green logistics represents direction and trend of future logistics development, and is a kind of new mode of the logistics industry under the guidance of strategic guidance of scientific development concept and constr... Green logistics represents direction and trend of future logistics development, and is a kind of new mode of the logistics industry under the guidance of strategic guidance of scientific development concept and construction guideline of ecological civilization. Various countries in the world gradually make green logistics activity as the focus of logistics industry development and actively study special technology of green logistics, thereby laying foundation for green and sustainable development of logistics. In China, green logistics starts later, and awareness on green logistics is very limited, We study current situation of green logistics development in China, analyze many problems at concept, regulations and policies, in- frastructure, technical information and logistics personnel of green logistics, and put forward specific suggestions for improving green logistics devel- opment in China. 展开更多
关键词 green logistics Current situation problemS COUNTERMEASURES China
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GRADIENT TYPE OF GREEN'S FUNCTION FOR PARABOLIC PROBLEM
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作者 陈传淼 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 1995年第1期85-90,共6页
Consider the piecewise linear finite element subspace S and parabolic semi discrete Green’s function of gradient type G h(t)∈Sk.The asymptotic optimal estimatedxdt【C|Inh| and two applications are discussed.
关键词 PARABOLIC problem green’s FUNCTION GRADIENT TYPE
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A Memetic Algorithm With Competition for the Capacitated Green Vehicle Routing Problem 被引量:9
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作者 Ling Wang Jiawen Lu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2019年第2期516-526,共11页
In this paper, a memetic algorithm with competition(MAC) is proposed to solve the capacitated green vehicle routing problem(CGVRP). Firstly, the permutation array called traveling salesman problem(TSP) route is used t... In this paper, a memetic algorithm with competition(MAC) is proposed to solve the capacitated green vehicle routing problem(CGVRP). Firstly, the permutation array called traveling salesman problem(TSP) route is used to encode the solution, and an effective decoding method to construct the CGVRP route is presented accordingly. Secondly, the k-nearest neighbor(k NN) based initialization is presented to take use of the location information of the customers. Thirdly, according to the characteristics of the CGVRP, the search operators in the variable neighborhood search(VNS) framework and the simulated annealing(SA) strategy are executed on the TSP route for all solutions. Moreover, the customer adjustment operator and the alternative fuel station(AFS) adjustment operator on the CGVRP route are executed for the elite solutions after competition. In addition, the crossover operator is employed to share information among different solutions. The effect of parameter setting is investigated using the Taguchi method of design-ofexperiment to suggest suitable values. Via numerical tests, it demonstrates the effectiveness of both the competitive search and the decoding method. Moreover, extensive comparative results show that the proposed algorithm is more effective and efficient than the existing methods in solving the CGVRP. 展开更多
关键词 Capacitated green VEHICLE ROUTING problem(CGVRP) COMPETITION k-nearest neighbor(kNN) local INTENSIFICATION memetic algorithm
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Adomian Decomposition Method with Green’s Function for Solving Tenth-Order Boundary Value Problems
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作者 Waleed Al-Hayani 《Applied Mathematics》 2014年第10期1437-1447,共11页
In this paper, the Adomian decomposition method with Green’s function (Standard Adomian and Modified Technique) is applied to solve linear and nonlinear tenth-order boundary value problems with boundary conditions de... In this paper, the Adomian decomposition method with Green’s function (Standard Adomian and Modified Technique) is applied to solve linear and nonlinear tenth-order boundary value problems with boundary conditions defined at any order derivatives. The numerical results obtained with a small amount of computation are compared with the exact solutions to show the efficiency of the method. The results show that the decomposition method is of high accuracy, more convenient and efficient for solving high-order boundary value problems. 展开更多
关键词 Adomian Decomposition Method Adomian’s POLYNOMIALS Tenth-Order BOUNDARY Value problems green’s Function
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A Bi-Objective Green Vehicle Routing Problem: A New Hybrid Optimization Algorithm Applied to a Newspaper Distribution
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作者 Júlio César Ferreira Maria Teresinha Arns Steiner 《Journal of Geographic Information System》 2021年第4期410-433,共24页
The purpose of this work is to present a methodology to provide a solution to a Bi-objective Green Vehicle Routing Problem (BGVRP). The methodology, illustrated using a case study (newspaper distribution problem) and ... The purpose of this work is to present a methodology to provide a solution to a Bi-objective Green Vehicle Routing Problem (BGVRP). The methodology, illustrated using a case study (newspaper distribution problem) and literature Instances, was divided into three stages: Stage 1, data treatment;Stage 2, “metaheuristic approaches” (hybrid or non-hybrid), used comparatively, more specifically: NSGA-II (Non-dominated Sorting Genetic Algorithm II), MOPSO (Multi-Objective Particle Swarm Optimization), which were compared with the new approaches proposed by the authors, CWNSGA-II (Clarke and Wright’s Savings with the Non-dominated Sorting Genetic Algorithm II) and CWTSNSGA-II (Clarke and Wright’s Savings, Tabu Search and Non-dominated Sorting Genetic Algorithm II);Stage 3, analysis of the results, with a comparison of the algorithms. An optimization of 19.9% was achieved for Objective Function 1 (OF<sub>1</sub>;minimization of CO<sub>2</sub> emissions) and consequently the same percentage for the minimization of total distance, and 87.5% for Objective Function 2 (OF<sub>2</sub>;minimization of the difference in demand). Metaheuristic approaches hybrid achieved superior results for case study and instances. In this way, the procedure presented here can bring benefits to society as it considers environmental issues and also balancing work between the routes, ensuring savings and satisfaction for the users. 展开更多
关键词 Bi-Objective green Vehicle Routing problem green Logistics Meta-Heuristic Procedures Case Study Literature Instances
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New Hybrid Algorithm Based on BicriterionAnt for Solving Multiobjective Green Vehicle Routing Problem
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作者 Emile Nawej Kayij Joél Lema Makubikua Justin Dupar Kampempe Busili 《American Journal of Operations Research》 2023年第3期33-52,共20页
The main objective of this paper is to propose a new hybrid algorithm for solving the Bi objective green vehicle routing problem (BGVRP) from the BicriterionAnt metaheuristic. The methodology used is subdivided as fol... The main objective of this paper is to propose a new hybrid algorithm for solving the Bi objective green vehicle routing problem (BGVRP) from the BicriterionAnt metaheuristic. The methodology used is subdivided as follows: first, we introduce data from the GVRP or instances from the literature. Second, we use the first cluster route second technique using the k-means algorithm, then we apply the BicriterionAntAPE (BicriterionAnt Adjacent Pairwise Exchange) algorithm to each cluster obtained. And finally, we make a comparative analysis of the results obtained by the case study as well as instances from the literature with some existing metaheuristics NSGA, SPEA, BicriterionAnt in order to see the performance of the new hybrid algorithm. The results show that the routes which minimize the total distance traveled by the vehicles are different from those which minimize the CO<sub>2</sub> pollution, which can be understood by the fact that the objectives are conflicting. In this study, we also find that the optimal route reduces product CO<sub>2</sub> by almost 7.2% compared to the worst route. 展开更多
关键词 Metaheuristics green Vehicle Routing problem Ant Colony Algorithm Genetic Algorithms green Logistics
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Numerical Solution of Singularly Perturbed Two-Point Boundary Value Problem via Liouville-Green Transform
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作者 Hradyesh Kumar Mishra Sonali Saini 《American Journal of Computational Mathematics》 2013年第1期1-5,共5页
In this paper, authors describe a Liouville-Green transform to solve a singularly perturbed two-point boundary value problem with right end boundary layer in the interval [0, 1]. They reply Liouville-Green transform i... In this paper, authors describe a Liouville-Green transform to solve a singularly perturbed two-point boundary value problem with right end boundary layer in the interval [0, 1]. They reply Liouville-Green transform into original given problem and finds the numerical solution. Then they implemented this method on two linear examples with right end boundary layer which nicely approximate the exact solution. 展开更多
关键词 Singular Perturbation Ordinary Differential Equation BOUNDARY Layer TWO-POINT BOUNDARY Value problem Liouville-green TRANSFORM
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A Study of Optimum Switching Problem for Production Systems Considering Efficiency, Delivery Time and Green Evaluation
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作者 Jing Sun Mingjuan Zhao +1 位作者 Akihiro Yano Hisashi Yamamoto 《Journal of Computer and Communications》 2023年第2期158-171,共14页
This paper aims to derive the optimal switching strategy for production system considering efficiency, delivery time and green evaluation. Nowadays more and more manufacturing and logistics systems not only pursue bet... This paper aims to derive the optimal switching strategy for production system considering efficiency, delivery time and green evaluation. Nowadays more and more manufacturing and logistics systems not only pursue better work efficiency, but also focus on green energy evaluation issues. Cost reduction and shortening of delivery time are always important management issues in pursuit of efficiency and optimization of the entire production system because of global production competition. In a market situation where customer needs change in various ways, in particular, due to inadequate quality, changes in the local environment, natural disasters and so on. Therefore, prompt planning of management measures such as switching work processes and changing production methods has become an important issue. On the other hand, since the Paris Agreement came into effect, the construction of an environment-friendly production system has been required as an approach to environmental problems such as global warming. In this paper, we propose an optimum switching model of production systems considering efficiency, delivery time and green evaluation using a green evaluation index (GEC: Green Energy Coefficient). We also discuss the optimal switching strategy by numerical observation. 展开更多
关键词 green Evaluation Sustainable Production Optimal Switching problem Production Networks Decarbonization Manufacture Management
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金融科技对我国新能源产业信贷风险的影响研究
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作者 李继翠 裴旭东 《商业观察》 2026年第4期114-117,共4页
在“双碳”目标推进与能源结构转型深化的双重背景下,新能源产业已跃升为我国经济高质量发展的关键引擎。然而,该产业固有的高投入、长周期、强技术依赖特征,加上传统信贷风险管理模式存在的信息壁垒与效率短板,使得其信贷风险问题日益... 在“双碳”目标推进与能源结构转型深化的双重背景下,新能源产业已跃升为我国经济高质量发展的关键引擎。然而,该产业固有的高投入、长周期、强技术依赖特征,加上传统信贷风险管理模式存在的信息壁垒与效率短板,使得其信贷风险问题日益突出。金融科技依托大数据、人工智能、区块链等,具有技术优势,为突破这一困境提供了创新性解决方案。但在实际应用中,仍面临数据治理阻滞、技术适配偏差、监管机制滞后等难题。文章系统梳理了金融科技在新能源产业信贷风险管控中的应用现状,深入剖析制约其效能发挥的核心问题,并针对性提出优化路径,旨在为提升新能源产业信贷风险管控效能、推动绿色金融高质量发展提供实践参考。 展开更多
关键词 金融科技 新能源产业 信贷风险管控 问题对策 绿色金融
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直角平面区域内固定圆形刚性夹杂问题的Green函数解 被引量:9
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作者 史文谱 刘殿魁 宋永涛 《固体力学学报》 CAS CSCD 北大核心 2006年第2期207-212,共6页
利用复变函数法、多极坐标移动技术研究了直角平面区域内含有固定圆形夹杂时的反平面问题Green函数解.首先构造出不含夹杂的完整直角平面区域内满足边界应力条件的入射位移场;其次,建立直角平面区域内固定圆形夹杂对该入射场产生的满足... 利用复变函数法、多极坐标移动技术研究了直角平面区域内含有固定圆形夹杂时的反平面问题Green函数解.首先构造出不含夹杂的完整直角平面区域内满足边界应力条件的入射位移场;其次,建立直角平面区域内固定圆形夹杂对该入射场产生的满足直角边界应力自由条件的散射波解,并由叠加原理得到介质内的总波场.最后利用夹杂边界处的位移条件确定出散射波解中的未知系数,最终得到问题的Green函数解,还通过算例讨论了夹杂边界处的径向应力和环向应力随不同波数、角度和不同夹杂位置及不同点源位置的变化情况.算例结果表明了该文方法的有效实用性. 展开更多
关键词 直角平面区域 复变函数法 多极坐标移动技术 反平面问题 green函数解 固定夹杂
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多点边值问题的Green函数 被引量:3
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作者 葛渭高 《徐州师范大学学报(自然科学版)》 CAS 2008年第2期11-16,共6页
Green函数是研究非线性常微分方程边值问题的重要工具.借助Green函数将微分方程边值问题解的存在性转化成算子不动点的存在性,便于给出边值问题的有解性、多解性以及唯一性的条件.本文给出半齐次线性边值问题Green函数的一般定义,它适... Green函数是研究非线性常微分方程边值问题的重要工具.借助Green函数将微分方程边值问题解的存在性转化成算子不动点的存在性,便于给出边值问题的有解性、多解性以及唯一性的条件.本文给出半齐次线性边值问题Green函数的一般定义,它适用于二阶及高阶方程的两点和多点边值问题,并给出计算方法和若干算例. 展开更多
关键词 微分方程 边值问题 green函数
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关于两相饱和介质中流相Green函数的解析解 被引量:9
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作者 丁伯阳 宋新初 袁金华 《地球物理学报》 SCIE EI CAS CSCD 北大核心 2009年第7期1858-1866,共9页
自然界中许多动力学问题需要用两相饱和介质Green函数求得解答,本文在两相饱和介质位移场Green函数解答的基础上,求得的有关饱和流体孔隙压力,进、排流体流量等三个Green函数.从而使两相饱和介质涉及流体问题的Lamb方程能完整地使用.论... 自然界中许多动力学问题需要用两相饱和介质Green函数求得解答,本文在两相饱和介质位移场Green函数解答的基础上,求得的有关饱和流体孔隙压力,进、排流体流量等三个Green函数.从而使两相饱和介质涉及流体问题的Lamb方程能完整地使用.论文在推导过程中详细地阐述了流体三个Green函数的物理意义,并将所得结果与Chen(1994)的纯数学的结果作了了对比.最后文章讨论了解析解的稳定性. 展开更多
关键词 两相饱和介质 流体问题 green函数
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具有转移条件的两个区间Sturm-Liouville算子的Green函数和渐近展开(英文) 被引量:2
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作者 牡丹 孙炯 姚斯琴 《应用数学》 CSCD 北大核心 2014年第3期658-672,共15页
考虑具有转移条件的两个区间Sturm-Liouville算子.定义与转移条件相关联的的Hilbert空间,并在新Hilbert空间里讨论两个区间Sturm-Liouville算子.进一步构造具有转移条件的两个区间Sturm-Liouville算子的Green函数,并且给出两个区间Sturm... 考虑具有转移条件的两个区间Sturm-Liouville算子.定义与转移条件相关联的的Hilbert空间,并在新Hilbert空间里讨论两个区间Sturm-Liouville算子.进一步构造具有转移条件的两个区间Sturm-Liouville算子的Green函数,并且给出两个区间Sturm-Liouville算子的特征值和特征函数的渐近展开. 展开更多
关键词 两个区间Sturm-Liouville算子 渐近展开 green函数
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三维层状饱和地基动力Green函数的薄层法求解 被引量:2
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作者 王鹏 史吏 +1 位作者 王军 刘凯 《岩土力学》 EI CAS CSCD 北大核心 2014年第12期3602-3610,3635,共10页
建立了三维层状饱和地基模型并在模型底部施加无反射边界条件,引入Fourier变换和正交变换将饱和地基Biot动力方程化为Love和Rayleigh模态方程,将地基沿深度方向划分为数个薄层单元并对单元位移场引入线性插值函数,从而将模态方程离散化... 建立了三维层状饱和地基模型并在模型底部施加无反射边界条件,引入Fourier变换和正交变换将饱和地基Biot动力方程化为Love和Rayleigh模态方程,将地基沿深度方向划分为数个薄层单元并对单元位移场引入线性插值函数,从而将模态方程离散化,通过求解本征值问题最终给出了三维层状饱和地基的频域动力Green函数。分析了均质饱和地基的Love和Rayleigh模态的弥散特性,求解了均质和成层饱和半空间的Lamb问题,并与Philippacopoulos的数值积分解对比,说明了所求Green函数的正确性。所得Green函数无需关于Hankel函数进行数值逆变换且能直接考虑地基的成层性,提高了计算效率。 展开更多
关键词 饱和地基 薄层法 green函数 LAMB问题
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具有转移条件的Sturm-Liouville问题的Green函数 被引量:2
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作者 牡丹 《湖北民族学院学报(自然科学版)》 CAS 2015年第4期379-383,共5页
考虑了具有转移条件的Sturm-Liouville问题,即在有限区间上具有转移条件的问题,并给出了具有转移条件的Sturm-Liouville问题的Green函数.
关键词 STURM-LIOUVILLE问题 转移条件 green函数
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压电半无限体轴对称问题Green函数
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作者 丁皓江 陈伟球 《重庆建筑大学学报》 EI CSCD 2000年第6期5-6,共2页
丁皓江等曾于 1 999年在 International Journal of Solids and Structures上发表过关于此问题的解 ,可惜在公布的公式中遗漏了一些项 。
关键词 压电半无限体 轴对称问题 green函数
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调和方程Dirichlet外问题的Green函数研究 被引量:1
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作者 赵天玉 李凯 《长江大学学报(自科版)(上旬)》 CAS 2010年第2期7-10,共4页
调和方程在科学实践和工程技术中有广泛的应用。在以基本解方式定义Green函数的基础上,导出了有界区域外部调和函数的积分表达式,并给出了调和方程Dirichlet外问题的Green函数及其满足的条件,最后用此Green函数给出了调和方程球域外Diri... 调和方程在科学实践和工程技术中有广泛的应用。在以基本解方式定义Green函数的基础上,导出了有界区域外部调和函数的积分表达式,并给出了调和方程Dirichlet外问题的Green函数及其满足的条件,最后用此Green函数给出了调和方程球域外Dirichlet问题的解。 展开更多
关键词 调和方程 green函数 条件 DIRICHLET问题
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The Planning of Urban Green Space System Based on the Concept of Conservation-oriented Landscape 被引量:1
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作者 赵岩 王浩 《Journal of Landscape Research》 2009年第10期18-22,共5页
Through analyzing problems in the planning of green space system in cities of China,strategies for constructing urban green space system are put forward based on the requirements of conservation-oriented landscape.
关键词 Conservation-oriented LANDSCAPE CONCEPT URBAN green space system problem Application
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