In this paper,a novel location inventory routing(LIR)model is proposed to solve cold chain logistics network problem under uncertain demand environment. The goal of the developed model is to optimize costs of location...In this paper,a novel location inventory routing(LIR)model is proposed to solve cold chain logistics network problem under uncertain demand environment. The goal of the developed model is to optimize costs of location,inventory and transportation.Due to the complex of LIR problem( LIRP), a multi-objective genetic algorithm(GA), non-dominated sorting in genetic algorithm Ⅱ( NSGA-Ⅱ) has been introduced. Its performance is tested over a real case for the proposed problems. Results indicate that NSGA-Ⅱ provides a competitive performance than GA,which demonstrates that the proposed model and multi-objective GA are considerably efficient to solve the problem.展开更多
Due to the problem complexity, simultaneous solution methods are limited. A hybrid algorithm is emphatically proposed for LRP. First, the customers are classified by clustering analysis with preference-fitting rules. ...Due to the problem complexity, simultaneous solution methods are limited. A hybrid algorithm is emphatically proposed for LRP. First, the customers are classified by clustering analysis with preference-fitting rules. Second, a chaos search (CS) algorithm for the optimal routes of LRP scheduling is presented in this paper. For the ergodicity and randomness of chaotic sequence, this CS architecture makes it possible to search the solution space easily, thus producing optimal solutions without local optimization. A case study using computer simulation showed that the CS system is simple and effective, which achieves significant improvement compared to a recent LRP with nonlinear constrained optimization solution. Lastly the pratical anlysis is presented relationship with regional logistics and its development in Fujian province.展开更多
The location of the distribution facilities and the routing of the vehicles from these facilities are interdependent in many distribution systems. Such a concept recognizes the interdependence;attempts to integrate th...The location of the distribution facilities and the routing of the vehicles from these facilities are interdependent in many distribution systems. Such a concept recognizes the interdependence;attempts to integrate these two decisions have been limited. Multi-objective location-routing problem (MLRP) is combined with the facility location and the vehicle routing decision and satisfied the different objectives. Due to the problem complexity, simultaneous solution methods are limited, which are given in different objectives with conflicts in functions satisfied. Two kinds of optimal mathematical models are proposed for the solution of MLRP. Three methods have been emphatically developed for MLRP. MGA architecture makes it possible to search the solution space efficiently, which provides a path for searching the solution with two-objective LRP. At last the practical proof is given by random analysis for regional distribution with nine cities.展开更多
Estimation of stochastic demand in physical distribution in general and efficient transport routs management in particular is emerging as a crucial factor in urban planning domain. It is particularly important in some...Estimation of stochastic demand in physical distribution in general and efficient transport routs management in particular is emerging as a crucial factor in urban planning domain. It is particularly important in some municipalities such as Tehran where a sound demand management calls for a realistic analysis of the routing system. The methodology involved critically investigating a fuzzy least-squares linear regression approach (FLLRs) to estimate the stochastic demands in the vehicle routing problem (VRP) bearing in mind the customer's preferences order. A FLLR method is proposed in solving the VRP with stochastic demands: approximate-distance fuzzy least-squares (ADFL) estimator ADFL estimator is applied to original data taken from a case study. The SSR values of the ADFL estimator and real demand are obtained and then compared to SSR values of the nominal demand and real demand. Empirical results showed that the proposed method can be viable in solving problems under circumstances of having vague and imprecise performance ratings. The results further proved that application of the ADFL was realistic and efficient estimator to face the sto- chastic demand challenges in vehicle routing system management and solve relevant problems.展开更多
Purpose–The purpose of this paper is to solve the capacitated location routing problem(CLRP),which is an NP-hard problem that involves making strategic decisions as well as tactical and operational decisions,using a ...Purpose–The purpose of this paper is to solve the capacitated location routing problem(CLRP),which is an NP-hard problem that involves making strategic decisions as well as tactical and operational decisions,using a hybrid particle swarm optimization(PSO)algorithm.Design/methodology/approach–PSO,which is a population-based metaheuristic,is combined with a variable neighborhood strategy variable neighborhood search to solve the CLRP.Findings–The algorithm is tested on a set of instances available in the literature and gave good quality solutions,results are compared to those obtained by other metaheuristic,evolutionary and PSO algorithms.Originality/value–Local search is a time consuming phase in hybrid PSO algorithms,a set of neighborhood structures suitable for the solution representation used in the PSO algorithm is proposed in the VNS phase,moves are applied directly to particles,a clear decoding method is adopted to evaluate a particle(solution)and there is no need to re-encode solutions in the form of particles after applying local search.展开更多
目的针对当前物流背景下普遍出现的送货公司外包、退换货频繁等问题,结合现有的碳排放政策,提出低碳背景下开放式同时送取货选址−路径模型(Low-Carbon Open Location-routing Problem with Simultaneous Pickup and Delivery Problem,LO...目的针对当前物流背景下普遍出现的送货公司外包、退换货频繁等问题,结合现有的碳排放政策,提出低碳背景下开放式同时送取货选址−路径模型(Low-Carbon Open Location-routing Problem with Simultaneous Pickup and Delivery Problem,LOLRPSPD),并通过改进野马算法进行求解。方法首先设计一种新的解码方式,使得原离散问题可以采用连续算法求解。之后,运用哈尔顿序列生成初始解,改进非线性进化概率因子,使用模拟二进制交叉,增加变异操作,以及精英保留、设置连续失败重新初始化等步骤,改进野马算法。最后,通过6组不同大小的算例将改进野马算法与原始野马算法、模拟退火算法、粒子群算法、遗传算法进行对比。结果针对中大型算例,改进野马算法远超原始野马算法。针对小型算例,在确保准确率的同时,改进野马算法对比各经典算法也在速度上具有优势。结论提出的LOLRPSD模型具备合理性,改进的野马算法针对选址路径问题具有较好的搜索能力。展开更多
针对同时送取货的选址路径问题(Location-routing Problem with Simultaneous Pickup and Delivery,LRPSPD),设计一种改进烟花算法(Improved Firework Algorithm,IFWA)求解。首先,考虑仓库建设、车辆启用、车辆路径等成本因素,建立最小...针对同时送取货的选址路径问题(Location-routing Problem with Simultaneous Pickup and Delivery,LRPSPD),设计一种改进烟花算法(Improved Firework Algorithm,IFWA)求解。首先,考虑仓库建设、车辆启用、车辆路径等成本因素,建立最小成本的LRPSPD模型,该模型强调需求点的送货需求和取货需求只能由一辆车同时进行服务。其次,设计一种改进烟花算法,该算法结合贪心聚类算法生成初始解,由烟花爆炸算子操作生成邻域解,利用变异操作协助产生新种群。最后,通过使用混合免疫算法、模拟退火算法求解相同算例,对结果进行分析比较,验证模型的可行性和改进算法的有效性。展开更多
针对碳定价背景下的低碳选址路径问题(Low-Carbon Location Routing Problem,LCLRP),首先构建了一种考虑油耗和碳排放成本,并以最小化设施选址成本、车辆启用成本以及运输成本为目标的选址-路径模型;其次,根据模型的特征,设计了一种分...针对碳定价背景下的低碳选址路径问题(Low-Carbon Location Routing Problem,LCLRP),首先构建了一种考虑油耗和碳排放成本,并以最小化设施选址成本、车辆启用成本以及运输成本为目标的选址-路径模型;其次,根据模型的特征,设计了一种分布估计灰狼算法(Grey Wolf Optimizer with Estimation of Distribution Algorithms,GWOEDA)对其进行求解。算法利用概率模型引导灰狼,并利用多父代交叉和两种邻域搜索算子增强了算法的全局搜索与局部搜索性能。算例分析结果表明:加入概率模型学习能力的灰狼算法在选址路径问题上有更好的寻优能力,并且在碳定价背景下,所构建的模型可以有效降低总成本和碳排放量。展开更多
基金Natural Science Foundation of Shanghai,China(No.15ZR1401600)the Fundamental Research Funds for the Central Universities,China(No.CUSF-DH-D-2015096)
文摘In this paper,a novel location inventory routing(LIR)model is proposed to solve cold chain logistics network problem under uncertain demand environment. The goal of the developed model is to optimize costs of location,inventory and transportation.Due to the complex of LIR problem( LIRP), a multi-objective genetic algorithm(GA), non-dominated sorting in genetic algorithm Ⅱ( NSGA-Ⅱ) has been introduced. Its performance is tested over a real case for the proposed problems. Results indicate that NSGA-Ⅱ provides a competitive performance than GA,which demonstrates that the proposed model and multi-objective GA are considerably efficient to solve the problem.
文摘Due to the problem complexity, simultaneous solution methods are limited. A hybrid algorithm is emphatically proposed for LRP. First, the customers are classified by clustering analysis with preference-fitting rules. Second, a chaos search (CS) algorithm for the optimal routes of LRP scheduling is presented in this paper. For the ergodicity and randomness of chaotic sequence, this CS architecture makes it possible to search the solution space easily, thus producing optimal solutions without local optimization. A case study using computer simulation showed that the CS system is simple and effective, which achieves significant improvement compared to a recent LRP with nonlinear constrained optimization solution. Lastly the pratical anlysis is presented relationship with regional logistics and its development in Fujian province.
文摘The location of the distribution facilities and the routing of the vehicles from these facilities are interdependent in many distribution systems. Such a concept recognizes the interdependence;attempts to integrate these two decisions have been limited. Multi-objective location-routing problem (MLRP) is combined with the facility location and the vehicle routing decision and satisfied the different objectives. Due to the problem complexity, simultaneous solution methods are limited, which are given in different objectives with conflicts in functions satisfied. Two kinds of optimal mathematical models are proposed for the solution of MLRP. Three methods have been emphatically developed for MLRP. MGA architecture makes it possible to search the solution space efficiently, which provides a path for searching the solution with two-objective LRP. At last the practical proof is given by random analysis for regional distribution with nine cities.
文摘Estimation of stochastic demand in physical distribution in general and efficient transport routs management in particular is emerging as a crucial factor in urban planning domain. It is particularly important in some municipalities such as Tehran where a sound demand management calls for a realistic analysis of the routing system. The methodology involved critically investigating a fuzzy least-squares linear regression approach (FLLRs) to estimate the stochastic demands in the vehicle routing problem (VRP) bearing in mind the customer's preferences order. A FLLR method is proposed in solving the VRP with stochastic demands: approximate-distance fuzzy least-squares (ADFL) estimator ADFL estimator is applied to original data taken from a case study. The SSR values of the ADFL estimator and real demand are obtained and then compared to SSR values of the nominal demand and real demand. Empirical results showed that the proposed method can be viable in solving problems under circumstances of having vague and imprecise performance ratings. The results further proved that application of the ADFL was realistic and efficient estimator to face the sto- chastic demand challenges in vehicle routing system management and solve relevant problems.
文摘Purpose–The purpose of this paper is to solve the capacitated location routing problem(CLRP),which is an NP-hard problem that involves making strategic decisions as well as tactical and operational decisions,using a hybrid particle swarm optimization(PSO)algorithm.Design/methodology/approach–PSO,which is a population-based metaheuristic,is combined with a variable neighborhood strategy variable neighborhood search to solve the CLRP.Findings–The algorithm is tested on a set of instances available in the literature and gave good quality solutions,results are compared to those obtained by other metaheuristic,evolutionary and PSO algorithms.Originality/value–Local search is a time consuming phase in hybrid PSO algorithms,a set of neighborhood structures suitable for the solution representation used in the PSO algorithm is proposed in the VNS phase,moves are applied directly to particles,a clear decoding method is adopted to evaluate a particle(solution)and there is no need to re-encode solutions in the form of particles after applying local search.
文摘目的针对当前物流背景下普遍出现的送货公司外包、退换货频繁等问题,结合现有的碳排放政策,提出低碳背景下开放式同时送取货选址−路径模型(Low-Carbon Open Location-routing Problem with Simultaneous Pickup and Delivery Problem,LOLRPSPD),并通过改进野马算法进行求解。方法首先设计一种新的解码方式,使得原离散问题可以采用连续算法求解。之后,运用哈尔顿序列生成初始解,改进非线性进化概率因子,使用模拟二进制交叉,增加变异操作,以及精英保留、设置连续失败重新初始化等步骤,改进野马算法。最后,通过6组不同大小的算例将改进野马算法与原始野马算法、模拟退火算法、粒子群算法、遗传算法进行对比。结果针对中大型算例,改进野马算法远超原始野马算法。针对小型算例,在确保准确率的同时,改进野马算法对比各经典算法也在速度上具有优势。结论提出的LOLRPSD模型具备合理性,改进的野马算法针对选址路径问题具有较好的搜索能力。
文摘针对同时送取货的选址路径问题(Location-routing Problem with Simultaneous Pickup and Delivery,LRPSPD),设计一种改进烟花算法(Improved Firework Algorithm,IFWA)求解。首先,考虑仓库建设、车辆启用、车辆路径等成本因素,建立最小成本的LRPSPD模型,该模型强调需求点的送货需求和取货需求只能由一辆车同时进行服务。其次,设计一种改进烟花算法,该算法结合贪心聚类算法生成初始解,由烟花爆炸算子操作生成邻域解,利用变异操作协助产生新种群。最后,通过使用混合免疫算法、模拟退火算法求解相同算例,对结果进行分析比较,验证模型的可行性和改进算法的有效性。
文摘针对碳定价背景下的低碳选址路径问题(Low-Carbon Location Routing Problem,LCLRP),首先构建了一种考虑油耗和碳排放成本,并以最小化设施选址成本、车辆启用成本以及运输成本为目标的选址-路径模型;其次,根据模型的特征,设计了一种分布估计灰狼算法(Grey Wolf Optimizer with Estimation of Distribution Algorithms,GWOEDA)对其进行求解。算法利用概率模型引导灰狼,并利用多父代交叉和两种邻域搜索算子增强了算法的全局搜索与局部搜索性能。算例分析结果表明:加入概率模型学习能力的灰狼算法在选址路径问题上有更好的寻优能力,并且在碳定价背景下,所构建的模型可以有效降低总成本和碳排放量。