百色市农村客运站经营管理实践

农村客运站场网络是公路客运站场网络的重要组成部分,是发展农村客运、促进农村地区经济社会发展和城乡商品交流的重要平台.文章结合当前百色市农村客运站经营管理现状,分析经营管理中存在的问题,提出了相关的对策和措施.为规范当地农村客运市场秩序、加快农村客运网络建设、提高社会主义新农村建设水平提供参考.     

应将推进偏远山区城乡公交一体化列入发展规划

<正>改革城乡客运管理模式打破城市公交与农村客运二元分割的局面采用多样化的手段、用有效可行的模式改造城乡公交,合力促进偏远山区县市城乡公交一体化的早日开展。"偏远山区的农村客运发展没有达到与公路通村同步发展,农村客运网络还不健全,而且城市公交发展缓慢,经营效益不尽人意,假如在县城城市公交运营还不够成熟的情况下推进城乡公交一体化建设,以求"一步到位",恐怕会欲速而则不达。     

农村客运铺垫农村公交之路

城乡客运一体化建设,正在中华大地掀起建设的热潮。翻阅行业内的法律法规,至今无法将农村公交和农村客运严格的区分。但是笔者看了一些相关的资料后,认为农村客运是农村公交的前身,而随着时代的发展和人们对交通工具需求的变化,农村公交将代替农村客运,成为农村客运的发展归宿。目前,国家以惠民为前提,出台政策来加大对农村交通建设、交通运输的投入,已经实现这一举措的地方,农民受益良多。除东部经济发达地区,尤其是中西部地区企业和当地     

如何推进欠发达县市城乡公交一体化工作?

<正>"目前,在欠发达县市实施城"乡公交一体化还存在着诸多困难,但实施城乡公交一体化是统筹城乡发展的迫切要求,是党和国家"惠农"的战略决策,各相关部门要早部署、早规划、早行动,合力促进城乡公交一体化早日开展。"实施城乡公交一体化,是在新农村建设和城乡统筹发展战略的大背景下提出的,它根据城乡旅客运输发展的客观要求,改革现有的城乡客运管理模式,打破原来城市公交与农村客运二元分割的局面,利用公交化运作方式,充分发挥客运资源效益最大化,以达到城乡公交相互衔接、资源共享,使农民     

北京农村公交企业经营困局和对策

近几年，我国城乡一体化进程加快，农村剩余劳动力流向城市，城乡交流对客运的需求日益明显，农民对乘车条件和候车环境的要求已越来越高。以北京市为例，近年来，北京市大力发展公交，积极倡导公交优先，特别是在农村客运公交化方面下了很大手笔，对促进农村客运事业发展规划出了良好前景。     

河池市城乡公交客运发展思路探析

文章基于广西河池市城乡公交客运发展情况,分析了发展城乡公交客运存在的问题,提出了加快城乡公交客运发展的建议,为河池市加快发展城乡公交客运提供思路。     

钦州市城乡公交客运一体化初探

文章阐述了钦州市城乡公交客运发展现状及问题,分析了钦州市城乡公交客运一体化的必要性和可行性,提出了实现城乡公交客运一体化的具体措施。     

“十三五”期公路客运的供需形势及发展建议

首先从供需匹配角度,分析了当前我国公路客运在中长途城际客运、农村客运发展,以及综合客运枢纽(公路客运站)、普通公路客运站建设运营方面出现的一些问题;然后从需求角度,分析了当前及今后一段时期传统公路班线客运、个性化定制客运,以及农村客运发展面临的主要需求形势;最后从供给角度,针对主要问题和需求形势,从公平与共享、效率与创新两个方面,提出了对"十三五"期公路客运运营组织及客运站点建设的一些思考和建议。     

加速推进城乡公交一体化进程

城乡公交一体化就是根据城乡旅客运输发展的客观要求,为适应城乡一体化需要,采取一系列措施,改革现有的城乡客运管理模式,打破原来城市公交与农村客运二元分割的局面,利用公交化运作方式,发挥客运资源效益最大化。     

浙江金华:100个农村客运候车亭投入使用

2013年1月1日,在浙江金华婺城区虹戴公路上,一名乘客正在新建的公交候车亭内候车。为推进城乡公交一体化进程,加快农村客运基础设施建设,改善农村乘客候车条件,相关部门投资约240万元,在市本级建了100个农村客运候车亭,其中在婺城区虹戴公路建了30个,金安公路建了20个,金东区赤松镇上钱村至傅     

短小成品油管道批次和罐容的确定

为了研究短小成品油管道输送批次和罐容的确定方法,以安庆-合肥成品油管道为例,根据该工程线路短、管径小、不考虑分输、不需要新建储罐、混油量少等特点,经过综合比较确定管道输送的最大批次数,再综合分析首末站的实际情况,以充分利用首末站现有储罐、方便运行管理、减少混油损失为原则,来确定合适的批次和首末站的罐容.     

长输管道中泵的优化和节能技术

在长输管线中,泵站是输油系统中必不可少的部分,而且泵站的运行成本巨大。工况处于经常变化的输油系统是极为普遍的,在这些系统中,通常采用的节流调节法浪费能量。如果能很好地使用变频调速系统,能实现泵站的优化运行。文中介绍了泵机组变频节能工艺理论以及比例定律和相似抛物线的基本原理,并对调速后泵的转速和轴功率进行了计算,进行定速泵与变速泵串联运行试验,并比较了不同操作方式的能耗。     

Identifying the spatial distribution of public transportation trips by node and community characteristics

ABSTRACT

Identifying the spatial distribution of travel activities can help public transportation managers optimize the allocation of resources. In this paper, transit networks are constructed based on traffic flow data rather than network topologies. The PageRank algorithm and community detection method are combined to identify the spatial distribution of public transportation trips. The structural centrality and PageRank values are compared to identify hub stations; the community detection method is applied to reveal the community structures. A case study in Guangzhou, China is presented. It is found that the bus network has a community structure, significant weekday commuting and small-world characteristics. The metro network is tightly connected, highly loaded, and has no obvious community structure. Hub stations show distinct differences in terms of volume and weekend/weekday usage. The results imply that the proposed method can be used to identify the spatial distribution of urban public transportation and provide a new study perspective.     

成品油管道水击保护

长距离成品油管道在密闭输送过程中,出现非正常停泵、误关阀门及混油界面经过泵等均会引起水击现象发生。水击波沿管道传播,极易导致管道局部超压而造成管道破裂、损坏设备等,故水击保护成为成品油管道密闭输送关键性的工艺技术之一。金嘉湖成品油管道在全线水击保护控制方面采用了进出站压力调节系统、分输站分油流量调节系统、出站压力超高泄放系统、进站低压泄放保护系统、进出站压力超限停泵联锁保护系统来保证管道事故工况时的安全。     

Defining and measuring service availability for complex transportation networks

Service Availability of a transportation system is a measure of a performance that has been generally defined according to the reliability and maintainability terms of mean-time-before-failure and mean-time-to-restore, as borrowed from the aerospace/defense industry. While such definitions correctly describe the availability of a system and its equipment to function they do not directly measure the percent of designed and scheduled service available for passenger use. For the more complex transportation systems having multiple tracks and routes, fleets of vehicles, more than two stations and more than one mode of service there are needs for definitions that account for isolated failures that partially interrupt or delay service. Successful definitions of service availability have been based on data that is easily and directly entered in the operating log or automatically collected by Automatic Train Supervision (ATS) system and reports generated by software. The following paper first defines measures of service availability in current use and analyzes exact and approximation methods for data collection and computation. Second, the paper postulates and explores classical and new definitions of service availability applicable for complex networks such as Personal Rapid Transit (PRT). Insight is provided for choosing a suitable definition based on the type of transportation network.     

含蜡原油管道低输量安全运行方案优化研究

以国内东部某油田的含蜡原油输油管道为研究对象,首先应用PIPEPHASE软件中的黑油网络模型计算出＂热力条件允许最小输量＂和＂管道特性允许最小输量＂,以确定管道最小输量。然后针对该管道即将进入低输量运行阶段的实际情况,分析了各种常用保障技术的可行性,并结合经济投入与生产管理2个方面的要求,通过对比优选出含水输送工艺,采用起点联合站掺水输送、终点联合站进行油水分离和污水处理,并扩建污水深度处理站的方案,以确保该管道的安全经济运行。     

Joint deployment of charging stations and photovoltaic power plants for electric vehicles

The focus of this study is to jointly design charging stations and photovoltaic (PV) power plants with time-dependent charging fee, to improve the management of the coupled transportation and power systems. We first propose an efficient and extended label-setting algorithm to solve the EV joint routing and charging problem that considers recharging amount choices at different stations and loop movement cases. Then, a variational inequality problem is formulated to model the equilibrium of EV traffic on transportation networks, and an optimal power flow model is proposed to model the power network flow with PV power plants and optimally serve the EV charging requirements. Based on the above models for describing system states, we then formulate a model to simultaneously design charging stations, PV plants, and time-dependent charging fee. A surrogate-based optimization (SBO) algorithm is adopted to solve the model. Numerical examples demonstrate that the proposed SBO algorithm performs well. Additionally, important insights concerning the infrastructure design and price management of the coupled transportation and power networks are derived accordingly.     

Integrated planning of static and dynamic charging infrastructure for electric vehicles

This paper investigates the optimal deployment of static and dynamic charging infrastructure considering the interdependency between transportation and power networks. Static infrastructure means plug-in charging stations, while the dynamic counterpart refers to electrified roads or charging lanes enabled by charging-while-driving technology. A network equilibrium model is first developed to capture the interactions among battery electric vehicles’ (BEVs) route choices, charging plans, and the prices of electricity. A mixed-integer bi-level program is then formulated to determine the deployment plan of charging infrastructure to minimize the total social cost of the coupled networks. Numerical examples are provided to demonstrate travel and charging plans of BEV drivers and the competitiveness of static and dynamic charging infrastructure. The numerical results on three networks suggest that (1) for individual BEV drivers, the choice between using charging lanes and charging stations is more sensitive to parameters including value of travel time, service fee markup, and battery size, but less sensitive to the charging rates and travel demand; (2) deploying more charging lanes is favorable for transportation networks with sparser topology while more charging stations can be more preferable for those denser networks.     

Determining the optimal number of seasonal adjustment factor groupings when estimating annual average daily traffic and investigating their characteristics

Although cluster analysis is recommended by the US Traffic Monitoring Guide (TMG) to supplement the development of seasonal adjustment factor groupings (SAFGs), the relationships among SAFGs' characteristics remain undiscovered, while the determination of the optimal number of clusters is an ambiguous task exposed to great subjectivity. Statistical indicators provide a mathematical solution by removing engineering judgment without taking into consideration any guidelines or other criteria, necessary for transportation planners to generate ‘practical and sensible’ groupings. The method examined in this study aims to overcome the above weaknesses incorporating into the methodology a series of statistics, recommendations, and previous research findings. The investigation of the relationships among (1) the within-group variation, (2) the total number of sites, (3) the minimum number of stations within a cluster, (4) the optimal number of clusters, and (5) the geographical size of the groups constitutes the main objectives of this research. According to the results, the cluster variability declines as the available number of stations increases. When the minimum number of stations within a cluster increases, the weighted coefficient of variation inflates as well, with the rate of increase depending on sample size. The average number of automatic traffic recorders per cluster is analogous to the sample size, while the optimal number of clusters varies conversely with the minimum number of stations within a cluster. The application developed for the conduct of the analysis minimizes the computational time needed, while it can be easily implemented by engineers to automate the process recommended by the TMG, enhancing the current state of practice.