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Determining effective criteria for the selection of MDF industry locations in Mazandaran Province: Application of AHP 被引量:1
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作者 M.AZIZI M.RAMEZANZADEH 《Forestry Studies in China》 CAS 2013年第3期222-230,共9页
Selecting the optimum location with attention to conditions and restrictions is one of the most importantfactors in establishing a manufacturing plant. Identification of effective criteria is an important stage in the... Selecting the optimum location with attention to conditions and restrictions is one of the most importantfactors in establishing a manufacturing plant. Identification of effective criteria is an important stage in the selection for the location of industrial units. In this study, an analytic hierarchy process (AHP) was applied to select the most effective criteria for the location of MDF (medium density fiberboard) industry in Mazandaran Province, Iran. A consideration in ttaining this goal is that Mazandaran is favored over other provinces because of its resources of raw lignocellulosic ma- erial required for wood and paper industries. The results indicate that the criterion of "materials and products" and the ub-criterion of "reliability of supply of raw material" are the most important factors. 展开更多
关键词 CRITERION AHP MDF industry selection of location Mazandaran Province
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Influential Factors in Employment Location Selection Based on “Push-Pull” Migration Theory—A Case Study in Three Gorges Reservoir Area in China 被引量:10
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作者 XU Ding-de ZHANG Ji-fei +3 位作者 XIE Fang-ting LIU Shao-quan CAO Meng-tian LIU En-lai 《Journal of Mountain Science》 SCIE CSCD 2015年第6期1562-1581,共20页
In China, farmers employed in non-farm work have become important socio-economic actors, but few studies have examined the farmers' perspective in making their work location choices. Based on "push-pull"... In China, farmers employed in non-farm work have become important socio-economic actors, but few studies have examined the farmers' perspective in making their work location choices. Based on "push-pull" migration theory, this paper utilizes sectional data from a 2013 survey of farmers in China's Three Gorges Reservoir area to empirically analyze the factors influencing migrant workers' choice of employment location. The results indicate that 60.46% of laborers have migrated from their home province, whereas 39.54% have remained in their home province. Focusing on personal, household, and community characteristics—in addition to the economic characteristics of the sample counties—multinomial logistic regression models reveal that farmer-laborers' employment location decisions are influenced by their personal capital endowment(age, years of education and social networks), family structure(the number of laborers, elders, children and students), home village characteristics(location, economic development level and the degree of relief of the land) and home county economic development level. Notably, male and female laborers' location decisions reveal a converging trend, and their differences are not pronounced. Per capita arable land area has little influence on location decisions, whereas the educational level of laborers has a significant impact. The results differ significantly from those found in previous studies. 展开更多
关键词 Off-farm employment location selection Migrants Push-Pull migration theory Three Gorges Reservoir region China
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Variable selection for skew-normal mixture of joint location and scale models
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作者 WU Liu-cang YANG Song-qin TAO Ye 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2021年第4期475-491,共17页
Although there are many papers on variable selection methods based on mean model in the nite mixture of regression models,little work has been done on how to select signi cant explanatory variables in the modeling of ... Although there are many papers on variable selection methods based on mean model in the nite mixture of regression models,little work has been done on how to select signi cant explanatory variables in the modeling of the variance parameter.In this paper,we propose and study a novel class of models:a skew-normal mixture of joint location and scale models to analyze the heteroscedastic skew-normal data coming from a heterogeneous population.The problem of variable selection for the proposed models is considered.In particular,a modi ed Expectation-Maximization(EM)algorithm for estimating the model parameters is developed.The consistency and the oracle property of the penalized estimators is established.Simulation studies are conducted to investigate the nite sample performance of the proposed methodolo-gies.An example is illustrated by the proposed methodologies. 展开更多
关键词 heterogeneous population skew-normal(SN)distribution mixture of joint location and scale models variable selection EM algorithm
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Optimal Location of Renewable Energy Generators in Transmission and Distribution System of Deregulated Power Sector:A Review
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作者 Digambar Singh Najat Elgeberi +3 位作者 Mohammad Aljaidi Ramesh Kumar Rabia Emhamed Al Mamlook Manish Kumar Singla 《Energy Engineering》 2025年第3期823-859,共37页
The literature on multi-attribute optimization for renewable energy source(RES)placement in deregulated power markets is extensive and diverse in methodology.This study focuses on the most relevant publications direct... The literature on multi-attribute optimization for renewable energy source(RES)placement in deregulated power markets is extensive and diverse in methodology.This study focuses on the most relevant publications directly addressing the research problem at hand.Similarly,while the body of work on optimal location and sizing of renewable energy generators(REGs)in balanced distribution systems is substantial,only the most pertinent sources are cited,aligning closely with the study’s objective function.A comprehensive literature review reveals several key research areas:RES integration,RES-related optimization techniques,strategic placement of wind and solar generation,and RES promotion in deregulated powermarkets,particularly within transmission systems.Furthermore,the optimal location and sizing of REGs in both balanced and unbalanced distribution systems have been extensively studied.RESs demonstrate significant potential for standalone applications in remote areas lacking conventional transmission and distribution infrastructure.Also presents a thorough review of current modeling and optimization approaches for RES-based distribution system location and sizing.Additionally,it examines the optimal positioning,sizing,and performance of hybrid and standalone renewable energy systems.This paper provides a comprehensive review of current modeling and optimization approaches for the location and sizing of Renewable Energy Sources(RESs)in distribution systems,focusing on both balanced and unbalanced networks. 展开更多
关键词 Optimization of RESs distributed generation modeling and selection of RESs hybrid systems standalone systems optimal location
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基于co-location模式和本体的地址选择算法 被引量:1
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作者 包旭光 王丽珍 陈红梅 《计算机工程与应用》 CSCD 北大核心 2017年第24期15-22,共8页
选址问题是任何一个商业机构都要面临的重大决策问题之一,它受多种因素制约,比如社会经济学、地质学、生态学以及决策者的特定需求等。现有的选址方法(通常被经济学家采用)大多利用主观评价,可扩展性差。空间co-location模式挖掘是空间... 选址问题是任何一个商业机构都要面临的重大决策问题之一,它受多种因素制约,比如社会经济学、地质学、生态学以及决策者的特定需求等。现有的选址方法(通常被经济学家采用)大多利用主观评价,可扩展性差。空间co-location模式挖掘是空间数据挖掘的一个重要研究方向。一个频繁co-location模式是一组空间特征的子集,它们的实例在空间中频繁关联。利用co-location模式的这种特征间"共存"关系,提出了一种基于co-location模式的地址选择算法,该算法基于本体描述空间数据的分类信息,并在本体的指导下对用户感兴趣的兴趣点(Point of Interest)进行关键co-location模式挖掘,同时针对实际情况对数据进行了预处理以增加算法的有效性。在真实数据集(北京市的兴趣点数据)上的评估实验显示该算法具有较高的准确率,选择的地址具有高可靠性。 展开更多
关键词 空间模式挖掘 CO-location模式 本体 地址选择
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Location optimization of multiple distribution centers under fuzzy environment 被引量:7
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作者 Yong WANG Xiao-lei MA +2 位作者 Yin-hai WANG Hai-jun MAO Yong ZHANG 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2012年第10期782-798,共17页
Locating distribution centers optimally is a crucial and systematic task for decision-makers.Optimally located distribution centers can significantly improve the logistics system's efficiency and reduce its operat... Locating distribution centers optimally is a crucial and systematic task for decision-makers.Optimally located distribution centers can significantly improve the logistics system's efficiency and reduce its operational costs.However,it is not an easy task to optimize distribution center locations and previous studies focused primarily on location optimization of a single distribution center.With growing logistics demands,multiple distribution centers become necessary to meet customers' requirements,but few studies have tackled the multiple distribution center locations(MDCLs) problem.This paper presents a comprehensive algorithm to address the MDCLs problem.Fuzzy integration and clustering approach using the improved axiomatic fuzzy set(AFS) theory is developed for location clustering based on multiple hierarchical evaluation criteria.Then,technique for order preference by similarity to ideal solution(TOPSIS) is applied for evaluating and selecting the best candidate for each cluster.Sensitivity analysis is also conducted to assess the influence of each criterion in the location planning decision procedure.Results from a case study in Guiyang,China,reveals that the proposed approach developed in this study outperforms other similar algorithms for MDCLs selection.This new method may easily be extended to address location planning of other types of facilities,including hospitals,fire stations and schools. 展开更多
关键词 Multiple distribution centers location selection Clustering algorithm Axiomatic fuzzy set(AFS) Technique for order preference by similarity to ideal solution(TOPSIS)
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Evaluation of alternative criteria for determining the optimal location of RWIS stations 被引量:5
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作者 Tae J. Kwon Liping Fu 《Journal of Modern Transportation》 2013年第1期17-27,共11页
This article presents a comprehensive framework for determining the location of road weather information system (RWIS) stations over a regional road network. In the proposed methodology, the region is divided into a... This article presents a comprehensive framework for determining the location of road weather information system (RWIS) stations over a regional road network. In the proposed methodology, the region is divided into a grid of equal-sized zones which are considered as the minimum spatial unit for allocating a candidate set of RWIS stations. These zones are ranked according to a set of pre-specified criteria that reflect the needs for, and potential benefits from, real-time RWIS, including road surface temperature variability, precipitation, network traffic, and collision patterns. A case study based on the existing RWIS network in the province of Ontario was conducted to illustrate the major features of the proposed method and evaluate the implications of alternative loca- tion selection criteria. The findings of the study suggest that it is feasible to develop a systematic process for locating RWIS stations using an integrated location criterion to capture multiple factors being considered in prac- tice. The study has also revealed the need to establish quantitative models for estimating the benefit of real-time information from RWIS stations, which is the foundation of a cost-benefit-based RWIS location optimization model. 展开更多
关键词 RWIS Road surface temperature Accidentrate Traffic volume location selection criteria
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Exploring Location Pattern of Commercial Stores in Shichahai, Beijing from a Street Centrality Perspective 被引量:3
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作者 ZHANG Yuyang YANG Bowen +3 位作者 ZHANG Mengcai ZHANG Gong SONG Shanshan QI Ling 《Chinese Geographical Science》 SCIE CSCD 2019年第3期503-516,共14页
The location pattern of different commercial stores in Shichahai, a historic conservation area in Beijing, was investigated from a street centrality perspective. Many previous studies have investigated the relationshi... The location pattern of different commercial stores in Shichahai, a historic conservation area in Beijing, was investigated from a street centrality perspective. Many previous studies have investigated the relationship between street centrality and land use patterns or commercial activities at interurban or intraurban scales. We considered Shichahai in this study to determine if street centrality applied at the street scale and if the street network was the only factor influencing the selection of store location. First, the nearest neighbor index, nearest neighbor hierarchical spatial cluster(NNHSC), and kernel density estimation(KDE) methods were used to provide baseline spatial distributions of commercial stores. Second, urban network analysis(UNA) tools were used to measure the street centrality indices under two conditions, with and without the weighting of cultural relics calculated by a principal component analysis(PCA). Finally, both store locations and centrality values at nodes were transformed to one unit(raster pixel) for a correlation analysis.The results showed that three of the four store types were clustered and had their own hotspots that were mostly located in the eastern and central parts of city blocks. The most momentous findings were determined from the street centrality indices. Among the three store types with correlation coefficients above 0.5, all centrality indices with landmark weighting, except straightness, had higher correlations,with closeness with landmark weighting having the highest correlation, followed by betweenness with landmark weighting. Therefore,we statistically concluded that street centrality could apply at the street scale and that the street network was not the only factor that influenced store location pattern, with landmarks also playing a significant role. The results provide guidance in determining the selection strategy for stores in a historic conservation area. 展开更多
关键词 historic conservation area location selected behavior COMMERCIALIZATION LANDMARK influence Urban NETWORK Analysis tool street NETWORK REVIVAL
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Hub location of air cargo company in air alliance 被引量:2
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作者 Zhang Jin Yan Yan Tang Qiuyu 《Journal of Southeast University(English Edition)》 EI CAS 2020年第3期341-348,共8页
Based on the characteristics of the air alliance environment saving transport mileage,the hub location problem of the air cargo network was studied.First,the air alliance selection probability model was introduced to ... Based on the characteristics of the air alliance environment saving transport mileage,the hub location problem of the air cargo network was studied.First,the air alliance selection probability model was introduced to determine the alliance self-operation or outsourcing probability in different segments.Then,according to the location center rule,with the goal of minimizing the total cost,the hub location model was built.The improved immune chaos genetic algorithm was used to solve this model.The results show that the improved algorithm has stronger convergence and better effect than the immune genetic algorithm.When the number of hubs increases,the fixed cost increases,but the transportation cost decreases.The greater the discount factor,the fixed cost,and the self operating cost sharing coefficient,the higher the total network cost.The airline which joins the air alliance can greatly reduce the operating cost of airlines.Therefore,airlines should consider joining the alliance. 展开更多
关键词 air alliance air alliance selection probability hub location improved algorithm
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Location and Capacity Determination Method of Electric Vehicle Charging Station Based on Simulated Annealing Immune Particle Swarm Optimization 被引量:3
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作者 Jiulong Sun Yanbo Che +2 位作者 Ting Yang Jian Zhang Yibin Cai 《Energy Engineering》 EI 2023年第2期367-384,共18页
As the number of electric vehicles(EVs)continues to grow and the demand for charging infrastructure is also increasing,how to improve the charging infrastructure has become a bottleneck restricting the development of ... As the number of electric vehicles(EVs)continues to grow and the demand for charging infrastructure is also increasing,how to improve the charging infrastructure has become a bottleneck restricting the development of EVs.In other words,reasonably planning the location and capacity of charging stations is important for development of the EV industry and the safe and stable operation of the power system.Considering the construction and maintenance of the charging station,the distribution network loss of the charging station,and the economic loss on the user side of the EV,this paper takes the node and capacity of charging station planning as control variables and the minimum cost of system comprehensive planning as objective function,and thus proposes a location and capacity planning model for the EV charging station.Based on the problems of low efficiency and insufficient global optimization ability of the current algorithm,the simulated annealing immune particle swarm optimization algorithm(SA-IPSO)is adopted in this paper.The simulated annealing algorithm is used in the global update of the particle swarm optimization(PSO),and the immune mechanism is introduced to participate in the iterative update of the particles,so as to improve the speed and efficiency of PSO.Voronoi diagram is used to divide service area of the charging station,and a joint solution process of Voronoi diagram and SA-IPSO is proposed.By example analysis,the results show that the optimal solution corresponding to the optimisation method proposed in this paper has a low overall cost,while the average charging waiting time is only 1.8 min and the charging pile utilisation rate is 75.5%.The simulation comparison verifies that the improved algorithm improves the operational efficiency by 18.1%and basically does not fall into local convergence. 展开更多
关键词 Electric vehicle charging station location selection and capacity configuration loss of distribution system simulated annealing immune particle swarm optimization Voronoi diagram
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A Location Prediction Method Based on GA-LSTM Networks and Associated Movement Behavior Information 被引量:2
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作者 Xingxing Cao Liming Jiang +1 位作者 Xiaoliang Wang Frank Jiang 《Journal of Information Hiding and Privacy Protection》 2020年第4期187-197,共11页
Due to the lack of consideration of movement behavior information other than time and location perception in current location prediction methods,the movement characteristics of trajectory data cannot be well expressed... Due to the lack of consideration of movement behavior information other than time and location perception in current location prediction methods,the movement characteristics of trajectory data cannot be well expressed,which in turn affects the accuracy of the prediction results.First,a new trajectory data expression method by associating the movement behavior information is given.The pre-association method is used to model the movement behavior information according to the individual movement behavior features and the group movement behavior features extracted from the trajectory sequence and the region.The movement behavior features based on pre-association may not always be the best for the prediction model.Therefore,through association analysis and importance analysis,the final association feature is selected from the pre-association features.The trajectory data is input into the LSTM networks after associated features and genetic algorithm(GA)is used to optimize the combination of the length of time window and the number of hidden layer nodes.The experimental results show that compared with the original trajectory data,the trajectory data associated with the movement behavior information helps to improve the accuracy of location prediction. 展开更多
关键词 location prediction information association feature selection GA-LSTM
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HOW TO MASTER THE DIFFERENTIATION OF SYNDROMES AND THE SELECTION OF ACUPOINTS QUICKLY
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作者 Zhuang JiaxiuInstitute of Acupuncture and Moxibustion, China Academy of TCM, Beijing 100700, China 《World Journal of Acupuncture-Moxibustion》 1994年第1期53-56,共4页
Differentiation of syndromes can be done by three steps:First to differentiate thenature of disease,second to differentiate the location of disease,third to analyse comprehensively thenature and location of disease.De... Differentiation of syndromes can be done by three steps:First to differentiate thenature of disease,second to differentiate the location of disease,third to analyse comprehensively thenature and location of disease.Depend on complete differentiation of syndromes,the acupoints are selected.Three cases are analysed to explain how to dominate preceding contents. 展开更多
关键词 DIFFERENTIATION of SYNDROMES selection of ACUPOINTS Nature of DISEASE location of DISEASE
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An improved multi-objective method for the selection of driverless taxi site locations
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作者 Yaqin He Yu Xiao +1 位作者 Jiehang Chen Daobin Wang 《International Journal of Transportation Science and Technology》 2025年第2期387-402,共16页
To expedite the large-scale deployment of driverless taxis and advance the autonomous driving industry,research on the location of integrated parking and charging facilities for driverless taxis has emerged as a signi... To expedite the large-scale deployment of driverless taxis and advance the autonomous driving industry,research on the location of integrated parking and charging facilities for driverless taxis has emerged as a significant issue in urban traffic.This study employs a progressive"preliminary selection-screening-optimal selection"approach for site selec-tion.First,the preliminary selection of parking sites is conducted by clustering various point-of-interest types.Subsequently,a multi-objective site selection model is developed to maximize the coverage of demand points,minimize construction costs,address the lar-gest population demands,and minimize the distance between demand points and candi-date sites.The non-dominated sorting genetic algorithmⅡ(NSGA-Ⅱ)is adopted to obtain several Pareto optimal solutions.The evaluation indexes are selected according to opera-tors,users,and the public transport system to estimate the Pareto optimal solutions,and then the final location solution can be obtained.The calculation methods for several key parameters are improved during the modeling process.Location potential and location influence coefficient are selected to adjust the number of driverless taxi parking spaces.Additionally,isochrones drawn based on the actual road network and path planning repre-sent the service range of candidate points.Meanwhile,distance based on actual road net-work rather than Euclidean distance is introduced to calculate the distance between candidate points.Finally,a case study shows that the method proposed in this study could reduce the total initial travel time to reach the demand points by 64%,which is indepen-dent of operational scheduling. 展开更多
关键词 Urban traffic Parking site selection Non-dominated sorting genetic algorithmⅡ(NSGA-Ⅱ) Driverless taxi Multi-objective location model
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考虑学习效应的灾情下应急救援点选址与建设任务调度研究
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作者 黄基诞 戴韬 窦玉浩 《东华大学学报(自然科学版)》 北大核心 2026年第1期189-200,共12页
设立应急救援点是地震等灾情下救援受伤灾民的最有效途径之一。如何合理地选择应急救援点位置,并安排工程队快速完成建设,是灾情救治的重点与难点。在模型建立方面:首先,将选址区域抽象为无向图,其中乡村作为节点,道路作为边;其次,将节... 设立应急救援点是地震等灾情下救援受伤灾民的最有效途径之一。如何合理地选择应急救援点位置,并安排工程队快速完成建设,是灾情救治的重点与难点。在模型建立方面:首先,将选址区域抽象为无向图,其中乡村作为节点,道路作为边;其次,将节点分为三种类型,即轻灾区(低风险区)、灾区(中风险区)、重灾区(高风险区),并根据相关文献提炼了应急救援点设置的基本规则。考虑到工程队建设应急救援点存在学习效应、各点之间的路程时间以及不同类型节点的优先级约束,构建了以最大完成时间为目标的选址与建设任务联合调度优化模型。在算法设计中,设计了采用三角形扰动机制的改进鲸鱼优化算法(WOA)。数值仿真结果表明,改进算法相较于经典的鲸鱼优化算法、遗传算法有一定的优势,验证了模型与算法的有效性。 展开更多
关键词 应急救援点 学习效应 选址 三角形扰动 鲸鱼优化算法(WOA)
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基于集成模型的地铁物流枢纽节点选址新方法研究
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作者 刘伟华 何洋 +1 位作者 张春雷 刘志雄 《物流技术》 2026年第1期31-45,共15页
地铁网络作为城市核心基础设施,凭借大运量、高准时性、低污染的显著优势,为物流模式创新提供了新路径。北京、深圳、天津等城市已启动地铁物流探索,依托现有地铁线路、站点及配套设施,在确保客运功能优先的基础上探索货物运输路径。然... 地铁网络作为城市核心基础设施,凭借大运量、高准时性、低污染的显著优势,为物流模式创新提供了新路径。北京、深圳、天津等城市已启动地铁物流探索,依托现有地铁线路、站点及配套设施,在确保客运功能优先的基础上探索货物运输路径。然而,地铁物流枢纽节点选址成为其规模化落地的核心阻碍,需突破多重复杂挑战。既要深度嵌入物流需求密集区域以缩短末端配送半径,又需与地铁线路、站点布局高效衔接,还需平衡成本类定量指标与服务质量、适配性等定性指标,决策难度远超传统物流选址。在这一复杂决策场景下,现有单一选址方法均表现出一定局限性,难以全面兼顾多元目标与约束条件。本文聚焦地铁物流枢纽节点选址问题,系统剖析集覆盖理论、P-中值法与层次分析法(AHP)的理论原理与应用逻辑,提出集成三种方法的综合选址新方法框架。通过集覆盖理论快速锁定初步范围,P-中值法筛选最优候选点组合,AHP量化评估优化,形成“理论解析—方法适配—流程整合—逻辑验证”的全流程方法论,为城市地铁物流枢纽规划提供可操作的技术路径。 展开更多
关键词 地铁物流 选址模型 集覆盖理论 P-中值法 层次分析法
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融合Epsilon约束与模糊数学规划的多目标粒子群选址优化算法
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作者 周倩 吴加洋 周宇航 《数据采集与处理》 北大核心 2026年第1期132-146,共15页
针对电动出租车充电设施选址中存在的空间分布失衡与利用率低下问题,本文提出一种融合Epsilon约束与模糊数学规划的多目标粒子群优化(Fuzzy mathematical programming based particle swarm optimization,FMPPSO)算法。通过构建涵盖土... 针对电动出租车充电设施选址中存在的空间分布失衡与利用率低下问题,本文提出一种融合Epsilon约束与模糊数学规划的多目标粒子群优化(Fuzzy mathematical programming based particle swarm optimization,FMPPSO)算法。通过构建涵盖土地成本、接客率及电池损耗的多约束选址模型,设计了基于模糊隶属度函数的自适应目标权重分配策略,解决传统进化算法在多目标优化中的早熟收敛难题。引入Epsilon约束机制,动态平衡收敛性与解集分布性,生成高质量Pareto前沿解集。最后通过仿真实验与对比分析验证FMPPSO算法在求解电动出租车充电设施选址问题上的有效性。 展开更多
关键词 电动出租车 充电设施选址 模糊数学规划 Epsilon约束 粒子群优化
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基于遥感和GIS的山东近海长牡蛎礁修复适宜性选址研究
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作者 斯张琦 李春霖 +2 位作者 尹子旭 项乐 刘阳 《水生生物学报》 北大核心 2026年第1期124-140,共17页
研究以山东半岛沿岸海域为研究区域,结合历史文献确定对适宜长牡蛎(Crassostrea gigas)生长及牡蛎礁修复有重要影响的海洋环境、栖息地及社会经济因素并划分相关因素阈值范围及最适条件,基于地理信息系统(GIS)与层次分析法(AHP),综合201... 研究以山东半岛沿岸海域为研究区域,结合历史文献确定对适宜长牡蛎(Crassostrea gigas)生长及牡蛎礁修复有重要影响的海洋环境、栖息地及社会经济因素并划分相关因素阈值范围及最适条件,基于地理信息系统(GIS)与层次分析法(AHP),综合2011—2020年的卫星遥感数据、数值模型数据、测深数据及社会经济数据,通过R语言进行空间叠加分析与时空统计,构建一套综合评价山东沿海长牡蛎礁修复的适宜指标体系,并探究其适宜性时空分布规律与环境影响机制。结果表明:山东近海长牡蛎礁修复适宜性总体以中、低适宜区为主,高适宜区主要分布于莱州湾东南部、烟台北部沿岸、荣成桑沟湾及乳山南部海域;适宜性季节特征明显,呈“冬缩夏扩”的演变规律;适宜性指数大于0.5的面积所占比例总体呈上升趋势,且存在明显的季度变化,与海水表面温度(SST)相关性最强,随着SST的升高而显著增加,与总悬浮颗粒物(TSS)呈负相关;基于适宜性的长牡蛎礁生态效益分析表明,夏季研究区域内有5个潜在的长牡蛎礁核心生境,呈现较为均匀的斑块状分布,可在近海形成较高的生态连通性,为牡蛎幼体扩散通道提供适宜环境条件。研究结果为山东近海长牡蛎礁生态修复的科学选址提供了理论依据。 展开更多
关键词 牡蛎礁修复 适宜性选址 长牡蛎 地理信息系统
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面向“公转铁”的域外仓选址与货流分配协同优化研究
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作者 韩宏 魏玉光 +1 位作者 刘栩瑞 夏阳 《北京交通大学学报》 北大核心 2026年第1期208-216,共9页
为解决公路与铁路在货运领域的竞争加剧,铁路货源流失现象日益严峻的问题,对域外仓选址与货流分配协同优化问题进行研究.首先,分析并指出在既有的港口物流组织模式下,具有“散、小、弱”特征的民营企业在铁路整列发运方面存在意愿不足... 为解决公路与铁路在货运领域的竞争加剧,铁路货源流失现象日益严峻的问题,对域外仓选址与货流分配协同优化问题进行研究.首先,分析并指出在既有的港口物流组织模式下,具有“散、小、弱”特征的民营企业在铁路整列发运方面存在意愿不足、能力有限的问题;其次,通过对比既有模式下港口货物运输径路与基于域外仓模式的港口货物运输径路,分析基于域外仓的港口物流组织模式,对于需求规模较小、资金实力有限的中小企业在减少其库存压力与运输成本方面优势;再次,聚焦域外仓选址与货流分配协同优化问题,构建基于服务网络的混合整数规划模型,综合考虑运输成本、建设成本等关键因素,以优化域外仓布局,提高公铁联运效率;最后,以天津港有色矿疏港过程为案例进行实证研究,验证该模型的有效性.研究结果表明:基于域外仓的港口物流组织模式相较于既有模式,可以较大程度地降低总运输成本,提升铁路周转量;在单域外仓模式下,总运营成本降低16.63%,铁路周转量占比45.18%;在多域外仓模式下,总运营成本降低30.81%,铁路周转量占比95.41%. 展开更多
关键词 公转铁 选址问题 服务网络 域外仓
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新质生产力发展能否推动地区产业协同布局——来自双重机器学习的因果推断
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作者 及添正 胡雪萍 《经济问题探索》 北大核心 2026年第1期126-147,共22页
本文从企业区位选择的视角切入,以区县级微观企业数据和异质性企业的区位选择关系为基础,构建城市产业协同布局指数的计算公式,利用双重机器学习模型考察了2012—2021年中国278个地级及以上城市新质生产力发展对产业协同布局的影响及相... 本文从企业区位选择的视角切入,以区县级微观企业数据和异质性企业的区位选择关系为基础,构建城市产业协同布局指数的计算公式,利用双重机器学习模型考察了2012—2021年中国278个地级及以上城市新质生产力发展对产业协同布局的影响及相关传导路径。研究发现:新质生产力发展显著推动了地区产业协同布局。机制检验表明,新质生产力通过供给侧与需求侧的双向机制吸引异质性企业进入,赋能产业协同布局。协同集聚环境的改善则强化了新质生产力对产业协同布局的积极作用。进一步分析表明,新质生产力对于产业协同布局的影响源自于新企业的增长而非企业迁移。在生产性服务的不同嵌入模式下,新质生产力对产业协同布局的影响表现出明显差异,其带动效果主要存在于制造业-传统型生产性服务业中,而对于制造业-高技术生产性服务业协同布局的正向影响则不明显。本研究有助于拓宽新质生产力研究的分析框架,也为如何依靠新质生产力赋能现代化产业体系建设提供了经验参考。 展开更多
关键词 新质生产力 异质性企业区位选择 产业协同布局
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顶板裂隙带L型井负压抽采瓦斯技术研究及应用——以靖远矿区魏家地煤矿为例
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作者 王勃 屈争辉 +5 位作者 白领国 徐波 田斌剑 李源汇 李长兴 张宇博 《煤炭科学技术》 北大核心 2026年第1期242-256,共15页
裂隙带L型井抽采是降低煤矿工作面瓦斯灾害的有效手段,但技术难度较高,选层选位难和水平段稳定性差等关键问题亟待解决。以魏家地煤矿东1100工作面为研究区,在地质工程适用性分析和覆岩结构精细刻画的基础上,运用关键层和“O”形圈理论... 裂隙带L型井抽采是降低煤矿工作面瓦斯灾害的有效手段,但技术难度较高,选层选位难和水平段稳定性差等关键问题亟待解决。以魏家地煤矿东1100工作面为研究区,在地质工程适用性分析和覆岩结构精细刻画的基础上,运用关键层和“O”形圈理论及高位环形裂隙体模型进行L型井选层定位,并采用Abaqus软件模拟回采条件下不同孔缝组合筛管应力变化,优选筛管规格,进一步开展工程实践与抽采效果评价,结果表明:(1)东1100工作面煤层瓦斯含量和压力较高、水平最大主应力方向NE、煤炭开采采用仰斜推进和U型通风方式,适宜裂隙带L型井抽采。(2)距煤层顶板70 m处的砂岩层介于裂隙带范围(41~140 m)内,且具有弹性模量大(37.53 GPa)、泊松比小(0.30)、厚度大(>5 m)和连续性好的特征,可作为其水平段的垂向优选层位,该层位“O”形圈裂隙带距离回风巷28.43~59.73 m,是水平段平面优选位置。(3)十字交叉排列的圆形开孔(直径10 mm,间距250 mm,孔密度20孔/m),筛管最大主应力和主应变数值最小,为L型井实施的优选筛孔设计方案。(4)实钻过程中采用CMD-100型钻机、7LZ172×7.0-XISF型单弯1.5°螺杆钻具和MWD无线随钻三开钻进筛管完井,负压抽采瓦斯纯量在0.4×10^(4)、1.1×10^(4)m^(3)/d间高位波动,稳产时间超500 d;期间工作面高位钻孔从20 m/组调整为50 m/组,配风量从1850 m^(3)/min降至1470 m^(3)/min,抽采率从52%提高到75%,实现矿井瓦斯与火的耦合防治。 展开更多
关键词 裂隙带L型井 地质工程适用性 选井选层 筛管规格 瓦斯抽采 魏家地煤矿
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