大城市客运交通系统出行方式特性分析

以我国大城市客运交通系统为研究对象,对各出行方式的出行距离与出行时耗分别进行了分布拟合.研究发现,采用k阶爱尔朗分布拟合表现出良好的适用性.在出行距离方面,小汽车与自行车的出行距离分布随机件最大,常规公交次之,城市轨道交通相对来说出行距离随机性最小;在出行时耗方面,自行车的时耗分布最为集中,小汽车与出租车次之,常规公交与城市轨道交通出行时耗分布范围最广.     

基于效应理论的出行方式抉择

文章将运用经济学中效应理论,通过无差异曲线分析在不同情况下,人们对小汽车、公交出行以及停车换乘P+R方式的抉择。对三种出行方式结合现实条件进行适当且合理的假设,建立小汽车—公交出行无差异曲线模型(公交资源稀缺)、小汽车—公交出行无差异曲线模型(公交资源健全)和智慧交通下的停车换乘P+R—公交出行无差异曲线模型,并在这三个无差异曲线模型中,分析出不同情况下的最优抉择,并合理推测未来交通出行方式的主流及前景。     

城市交通出行影响因素的计量检验

在国内外相关研究的基础上,通过国内40个交通出行样本数据的计量分析,建立了平均出行距离和出行时耗的多元回归方程,发现城市规模是影响单中心城市平均出行距离和出行时耗的主要因素,公交车分担率的提高相应增加了平均出行时耗,而高密度的城市开发有利于出行距离和出行时耗的降低.     

乌海市公交问卷调查分析报告

本次问卷调查从出行者出行方式选择、出行目的、出行距离、出行时间和费用消耗及出行意愿等几个方面进行调查,其结果一定程度上反映了乌海市出行者的整体状况,私家车出行日趋增加,公交出行仍然存在一些问题,如出行时耗大,舒适性、便利性较差等。但是可以通过改善公交出行环境来吸引更多的人优先选择公交出行,实施公交优先,以实现城市交通绿色、可持续发展的目的。     

多元交通一体化发展的国际比较及其启示

解决中国城市交通冲突、交通拥堵等问题的基本思路是发展多元交通模式,避免对小汽车的一元依赖.通过对欧美城市发展多元交通的历史比较,发现它们在汽车社会初期“以汽车为中心”的交通规划不仅没有化解交通冲突,反而使交通拥堵等问题愈演愈烈.20世纪60年代后欧洲城市致力于推进多元交通发展,效果显著.主要措施包括进行交通静化实践,以政策鼓励交通方式多元选择,以及建构公交、自行车、步行一体化的交通模式.而美国城市的认识和实践相对滞后,当前城市对小汽车依赖仍然严重.中国城市必须防止重蹈欧美国家当初的覆辙而走进“车本位”误区.为此,需要保障非小汽车出行人路权,完善慢行交通系统,提高城市公交的分担率和吸引力,保障行人和非机动车的安全.     

建设公交都市：基于产权及城市规划的视角——北京与东京出行结构差异分析

本文在对北京和东京交通出行结构进行比较的基础上,用出行方式选择模型说明不同的出行结构都是人们理性选择的结果。传统的交通拥堵治理思路是,让小汽车承担交通拥堵和空气污染的外部成本,来促使人们选择绿色交通出行。一种更包容的治理思路是产权的治理思路,这不仅考虑小汽车外部成本的权利配置对出行方式选择的影响,而且考虑城市空间资源配置对出行结构的影响。城市规划是规划城市空间资源的配置方式,其本质上是产权的配置,其中,交通便利性权利配置和空间便利性权利配置,会改变不同交通出行方式的效用曲线,从而决定人们的出行结构。这种思路或对如何引导公众选择绿色交通方式出行,建设公交都市提供有益启示。     

城市低收入群体的出行问题及其解决对策——以南京市为例

以南京市为例,选取交通支出与收入比、出行时耗、站点覆盖率和公交线网密度等指标对城市低收入人群的交通出行现状进行评价,揭示出城市低收入人群在出行中存在经济上的贫困、时间上的贫困、接受服务上的贫困和安全上的贫困等问题。进而从降低出行经济成本、减少出行时间成本、增加公交服务供给和保障慢行交通安全四方面提出了相应对策,以期为制定更为公平的城市交通政策提供依据。     

国外大城市交通发展模式及其评价

一、国外大城市交通的几种模式　　当今国外大城市的交通可分为以下三种模式:1.轨道模式代表性的城市是东京。据东京有关部门的调查,在东京日平均803万出行人次中,步行为56.5万人次,占总出行量的7%;轨道交通为591万人次,占总出行量的73.6%;小汽车为62.55万辆次,占总出行量的7.8%;自行车、摩托车为62万辆次,占总出行量的7.7%。可见东京的主要交通方式是轨道交通,即电车(在东京被称为高铁)与地铁。东京的各大会社有约定俗成的定规:公司“常务”以上的高级人员,上下班不准乘坐小汽车,只能乘坐公共交通工具,一般乘坐电车或地铁。实际上,不仅是常…     

石家庄公共交通和小汽车出行的使用者成本对比分析

<正>公共交通出行和小汽车出行是城市交通的两个最重要的组成部分,极大地影响着城市整体交通状况和居民日常生活质量。公共交通与小汽车的出行成本主要包括:提供者成本、使用者成本、社会成本。其中,使用者成本是人们在选择出行方式时最重要的参考指标。公共交通出行的使用者成本包括:公共交通票价、出行时间成本、舒适性成本;小汽车出行的使用者成本包括:出行时间成本、舒适性成本。本文旨在对公共交通和小汽车的使用者成本做出对比研究,以石家庄为例分析使用者成本对出行者在选择交通出行方式时的影响。一、出行使用者成本构成分析1.公共交通票价。公共交通票价主要是指出行者选用公共     

西安城市自行车交通规划及使用系统研究

随着城市的高速发展,"低碳生活,绿色出行"的理念越来越受到市民的重视.本文通过对国内外自行车出行经验及现状的对比分析.结合西安市本地现状,以缓解交通压力、实现低碳出行、促进休闲旅游、塑造公益城市形象为目标,通过对课题框架、设计模式、公益服务功能等相关基础理论的研究,提出了适合西安的城市自行车交通规划及使用系统,内含自行车停放站分布规划、自行车设计及配套设施使用原则及管理模式,力求通过自行车交通出行的推广及普及,为西安低碳城市建设做出贡献.     

Socio‐economic distance and spatial patterns in unemployment

This paper examines the spatial patterns of unemployment in Chicago between 1980 and 1990. We study unemployment clustering with respect to different social and economic distance metrics that reflect the structure of agents' social networks. Specifically, we use physical distance, travel time, and differences in ethnic and occupational distribution between locations. Our goal is to determine whether our estimates of spatial dependence are consistent with models in which agents' employment status is affected by information exchanged locally within their social networks. We present non‐parametric estimates of correlation across Census tracts as a function of each distance metric as well as pairs of metrics, both for unemployment rate itself and after conditioning on a set of tract characteristics. Our results indicate that there is a strong positive and statistically significant degree of spatial dependence in the distribution of raw unemployment rates, for all our metrics. However, once we condition on a set of covariates, most of the spatial autocorrelation is eliminated, with the exception of physical and occupational distance. Racial and ethnic composition variables are the single most important factor in explaining the observed correlation patterns. Copyright © 2002 John Wiley & Sons, Ltd.     

基于深度强化学习的动态共享单车重置问题研究

共享单车在为城市出行带来便利的同时,也面临着资源分布不平衡问题。针对单车分布动态变化环境下的共享单车重置问题,提出基于强化学习的实时调度策略结构。构建了面向强化学习的共享单车重置问题模型,利用深度确定性策略梯度算法(DDPG)进行求解,以获得实时调度策略。基于实际单车分布数据,构建了调度过程中的环境交互模拟器。最后,利用强化学习在模拟器中进行大规模数据实验,结果表明算法得到的调度策略能提高系统表现,并且效果好于已有方法。     

US city-size distribution and space

ABSTRACT

This paper focuses on spatial city-size distribution in the United States. It proposes a new distance-based approach to analyze the influence of distance on the city-size distribution parameter by considering the Pareto distribution and using data from different definitions of US cities in 2010. Considering all possible combinations of cities within a 300-mile radius, the results indicate that the Pareto distribution cannot be rejected in most cases regardless of city size. Placebo regressions validate the results, thereby confirming the significant effect of geography on the Pareto exponent.     

The adaptive approach for storage assignment by mining data of warehouse management system for distribution centres

Among distribution centre operations, order picking has been reported to be the most labour-intensive activity. Sophisticated storage assignment policies adopted to reduce the travel distance of order picking have been explored in the literature. Unfortunately, previous research has been devoted to locating entire products from scratch. Instead, this study intends to propose an adaptive approach, a Data Mining-based Storage Assignment approach (DMSA), to find the optimal storage assignment for newly delivered products that need to be put away when there is vacant shelf space in a distribution centre. In the DMSA, a new association index (AIX) is developed to evaluate the fitness between the put away products and the unassigned storage locations by applying association rule mining. With AIX, the storage location assignment problem (SLAP) can be formulated and solved as a binary integer programming. To evaluate the performance of DMSA, a real-world order database of a distribution centre is obtained and used to compare the results from DMSA with a random assignment approach. It turns out that DMSA outperforms random assignment as the number of put away products and the proportion of put away products with high turnover rates increase.     

基于行程费用的城市物流配送通道选择模型

从时间质量的角度出发,指出行程时间最小化和行程时间可靠性最大化是城市物流配送通道选择的两个重要目标。定义行程费用等于行程时间费用和行程时间可靠性费用的加权平均值。在此基础上,建立了基于行程费用的物流配送通道选择模型。最后,对北京市实际路网进行了实例分析。     

物流实时配送系统优化模型的构建与求解分析研究

为了解决物流实时配送系统过程的具体实施问题,以满足人们不断增长的物流需求,本文主要研究物流实时配送系统问题中,最优的配送中心个数,配送中心的选址,配送运输车辆行程路线安排,探讨寻求解决问题的有效方法,从而构建适当的运筹学数学模型,并对模型的求解进行深入透彻的分析研究,以实现整个集成物流系统的最小成本,从而实现最优化目标。为物流配送企业解决此类问题提供了思路和方法,并在部分企业进行了实证运用。     

Insights into the effect of traffic congestion on distribution network characteristics – a numerical analysis based on navigation service data

This research studies effects that the average increase in travel times due to road traffic congestion has on characteristics of an existing distribution network. It presents the most detailed estimate of ‘on-the-road’ effects on distribution network characteristics up to now, from the network modelling perspective and from the processed data point of view. A concrete network model allowing for the representation of all relevant transportation flows is presented. The processed traffic information relies on navigation service data. The use of such data allows the requirements that arise for the traffic analysis of a whole distribution network to be met. It is shown that this data source may considerably contribute in forthcoming research. The effects of traffic congestion are quantified to get insights into the extent to which regular traffic congestion affects distribution network characteristics and to understand the mitigating effect when the number of distribution centres is increased.     

带距离限制的双配送中心选址方法

研究了带距离限制的双配送中心选址问题,结合聚类算法、重心法、层次分析法构造了一个解决双配送中心选址问题的算法。首先根据聚类算法思想将整个配送服务区域划分为两部分,再计算出每一个区域的重心,并求出两重心点之间的距离与距离限制的差值,以差值为半径,两重心点分别为圆心作圆。找出两个圆内圈出的符合距离限制的所有备选地点对;若没有符合距离限制的备选地点对,则把半径扩大为原来的1.5倍,重复以上步骤,直至得到符合条件的备选地点对为止。然后结合层次分析法及模糊综合评价法对所有备选地点对进行筛选,得到最佳选址方案。     

Geodesic normal distribution on the circle

This paper is concerned with the study of a circular random distribution called geodesic normal distribution recently proposed for general manifolds. This distribution, parameterized by two real numbers associated to some specific location and dispersion concepts, looks like a standard Gaussian on the real line except that the support of this variable is [0, 2π) and that the Euclidean distance is replaced by the geodesic distance on the circle. Some properties are studied and comparisons with the von Mises distribution in terms of intrinsic and extrinsic means and variances are provided. Finally, the problem of estimating the parameters through the maximum likelihood method is investigated and illustrated with some simulations.