New Hybrid Algorithm Based on BicriterionAnt for Solving Multiobjective Green Vehicle Routing Problem

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 CO2 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 CO2 by almost 7.2% compared to the worst route.

A Study of Optimum Switching Problem for Production Systems Considering Efficiency, Delivery Time and Green Evaluation

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.

Existence of Monotone Positive Solution for a Fourth-Order Three-Point BVP with Sign-Changing Green’s Function

This paper is concerned with the following fourth-order three-point boundary value problem , where , we discuss the existence of positive solutions to the above problem by applying to the fixed point theory in cones and iterative technique.

A Memetic Algorithm With Competition for the Capacitated Green Vehicle Routing Problem

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.

Analysis of problems in urban green space system planning in China

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.

Problems and Countermeasures of Green Logistics Development in China

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.

Comprehensive form of solution for Lamb's dynamic problem expressed by Green's functions

By the analysis for the vectors of a wave field in the cylindrical coordinate and Sommerfeld＇s identity as well as Green＇s functions of Stokes＇ solution pertaining the conventional elastic dynamic equation, the results of Green＇s function in an infinite space of an axisymmetric coordinate are shown in this paper. After employing a supplementary influence field and the boundary conditions in the free surface of a senti-space, the authors obtain the solutions of Green＇s function for Lamb＇s dynamic problem. Besides, the vertical displacement uzz and the radial displacement urz can match Lamb＇s previous results, and the solutions of the linear expansion source u^r and the linear torsional source uee are also given in the paper. The authors reveal that Green＇s function of Stokes＇ solution in the semi-space is a comprehensive form of solution expressing the dynamic Lamb＇s problem for various situations. It may benefit the investigation of deepening and development of Lamb＇s problems and solution for pertinent dynamic problems conveniently.

Solutions of Green's function for Lamb's problem of a two-phase saturated medium

The solutions of Green’s function are significant for simplification of problem on a two-phase saturated medium.Using transformation of axisymmetric cylindrical coordinate and Sommerfeld’s integral,superposition of the influence field on a free surface,authors obtained the solutions of a two-phase saturated medium subjected to a concentrated force on the semi-space.

A Bi-Objective Green Vehicle Routing Problem: A New Hybrid Optimization Algorithm Applied to a Newspaper Distribution

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 (OF1;minimization of CO2 emissions) and consequently the same percentage for the minimization of total distance, and 87.5% for Objective Function 2 (OF2;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.

GRADIENT TYPE OF GREEN'S FUNCTION FOR PARABOLIC PROBLEM

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.

Adomian Decomposition Method with Green’s Function for Solving Tenth-Order Boundary Value Problems

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.

Numerical Solution of Singularly Perturbed Two-Point Boundary Value Problem via Liouville-Green Transform

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.

双重信息引导的蚁群算法求解绿色多舱车辆路径问题

针对当前实际运输中广泛存在的绿色多舱车辆路径问题(GMCVRP),文章提出一种双重信息引导的蚁群优化算法(DIACO)进行求解.首先,在DIACO的全局搜索阶段,重新构建传统蚁群优化算法(TACO)中的信息素浓度矩阵(PCM),使其同时包含客户块信息和客户序列信息,即建立具有双重信息的PCM(DIPCM),从而更全面学习和累积优质解的信息;采用3种启发式方法生成较高质量个体,用于初始化DIPCM,可快速引导算法朝向解空间中优质区域进行搜索.其次,在DIACO的局部搜索阶段,设计结合自适应策略的多种变邻域操作,用于对解空间的优质区域执行深入搜索.再次,提出信息素浓度平衡机制,以防止搜索陷入停滞.最后,使用不同规模的算例进行仿真测试和算法对比,结果验证了DIACO是求解GMCVRP的有效算法.

多车场异构车型绿色路径规划问题研究

为拓展多车场车辆路径类问题(MDVRP)的求解方式及途径,引入了油耗和碳排放量的近似计算方法,建立了带时间窗的多车场多车型绿色车辆路径问题模型(GMDHF-VRPTW)。将物流配送和碳排放总成本最小化作为优化目标,设计改进的禁忌搜索算法(ITS)求解该模型。为验证提出模型的有效性和可行性,采用Solomon测试数据集,分别从最优目标值、求解时间等方面与经典的禁忌算法进行对比,实验结果表明ITS方法有显著的优势。此外,为降低问题求解的复杂度,结合K-means聚类算法,将多车场转化为单车场,通过判断满足需求的最小车辆数进行建模并提出了基于Gurobi求解器的聚类过滤算法(CF),在求解同规模多车场多车型路径问题进行了探索,结果表明CF颇具优势,能够为企业实际的低碳物流运输提供决策支持和方法指导。

融入概率学习的混合差分进化算法求解绿色分布式可重入作业车间调度

本文针对绿色分布式可重入作业车间调度问题(GDRJSSP),提出一种融入概率学习的混合差分进化算法(HDE PL),以实现最大完工时间和总能耗最小.根据GDRJSSP的问题特点,设计编码和解码规则,并采用差分进化算法执行全局搜索来发现优质解区域.为能更明确地引导全局搜索方向,设计基于贝叶斯网络结构的多维概率模型合理学习和积累优质解(即当前种群中的较优解)的模式信息.结合问题解的结构特征,提出基于关键路径的4种邻域结构来构造局部搜索,并设计基于非关键路径的节能策略来提升算法获取低能耗非劣解的能力.仿真实验和算法对比验证了HDE PL可有效求解GDRJSSP.

绿色创新对企业投资效率的影响研究

在我国致力于实现“碳达峰”“碳中和”目标的背景下,绿色创新作为一种新型创新技术,对企业实现高质量发展及可持续发展至关重要。本文以2012—2021年我国A股上市公司为研究样本,实证检验绿色创新对企业投资效率的影响及融资约束与代理问题在其中的作用机制。研究发现,绿色创新能显著提高企业的投资效率,具体表现为抑制过度投资与缓解投资不足。机制检验发现,绿色创新能通过缓解融资约束与降低代理问题两条路径,提高企业的投资效率。异质性分析发现,在非重污染行业以及东部地区,绿色创新对投资效率的提升作用更显著。本文研究有助于推动企业与经济社会可持续发展。

基于文献计量和知识图谱的电动车辆路径问题研究综述

为揭示电动车辆路径问题领域的研究与发展现状,对CNKI和Web of Science数据库中电动车辆路径问题1994-2022年间的期刊文献进行知识挖掘与分析。基于文献计量学的量化分析与知识图谱的可视化,通过分析文献外部特征和共被引情况,梳理研究热点及热点演进趋势,归纳研究主题,总结出电动车辆路径问题的知识域包括研究主题和应用场景,其中,研究主题由变体研究、充电调度、求解方法三部分构成;对电动车辆路径问题在复杂实际问题、高效求解算法方面的未来发展进行展望,这将为电动车辆路径问题研究的深入化与国际化提供一定的推动作用。

饱和多孔介质中Lamb问题的Green函数解答

利用作者根据饱和多孔介质动力学方程快、慢纵波解耦求得的集中力作用下饱和多孔介质Green函数解答,通过柱坐标变换,运用Sommerfeld积分,再根据自由表面应力为零的特征,添加自由表面影响场,从而求得半无限空间集中力作用下饱和多孔介质动力学问题的解答.其结果与Philippacopoulos解答结果一致;当饱和多孔蜕化为单相时与Lamb的方程一致.整个推导过程明了,物理意义也较为清晰;方法符合常规解法.因此,该方法为简化与规范饱和多孔介质动力学问题的解答提供了基础;并且能为一直未解决的半无限空间饱和多孔介质动力学问题的流相解答(诸如孔隙压、排水量)提供解决途径.

三维层状饱和地基动力Green函数的薄层法求解

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。