北京就业与交通时空变动及计量关系研究

文章结合北京就业的时空变动特征以及对道路交通需求的变化特征,从区域要素角度考察城市交通和就业的关系。通过构建就业交通需求与交通供给量之间的计量关系模型,进行时间序列关系研究和横截面关系研究,分析得到北京市就业与交通道路建设之间的关系。     

供应链关系管理对策

建立战略合作伙伴关系是供应链战略管理的重点,也是集成化供应链管理的核心。在供应链合作伙伴关系环境下,合作伙伴之间能够建立一种长期稳定的、信任与合作的双赢的战略联盟关系。合作伙伴关系的潜在利润非常大,应从各个方面考虑对供应链关系的核心供应商关系的维持进行对策研究,并考虑如何更有效地提高供应商服务水平。     

加强收费站“四化”管理 努力构建和谐征缴关系

"四化"管理作为一种理念,对公路工作有着很强的指导性和针对性。实施"四化"管理,对实现收费公路科学发展、和谐发展和可持续发展有着深远的意义。构建和谐征缴关系,最关键就是处理好征费管理者与服务对象的关系。理顺征缴关系,就是要理顺缴费群体和内部事务关系。抓住"以人为本",促进征缴双方和谐,才能实现通行费征收事业全面协调发展。     

路面碾压混凝土试验研究

文章结合碾压混凝土在云南大理州农村公路中的应用,进行集料试验、配合比设计以及碾压混凝土力学性能分析,研究在不加粉煤灰情况下碾压混凝土用水量与细度模数的关系、用水量与砂率的关系以及水灰比与强度的关系。     

基于蛇形试验汽车操稳性主客观评价相关性研究

为实现汽车操纵稳定性主观评价客观化,以实车蛇行试验为例,研究汽车操稳性主观得分与客观测量数据之间的关系,建立相关性"最优"模型。结果表明,在小样本情况下,主观评价得分分别与平均转向盘转角无线性相关关系,与平均横摆角速度正线性相关关系,与平均车身侧倾角、平均侧向加速度负线性相关关系;平均横摆角速度对主观评价得分影响最显著,平均侧向加速次之,平均车身侧倾角最小。     

配比建筑垃圾再生材料大型固结试验分析

本文利用室内大型固结试验,分析了建筑垃圾再生材料三种配比、四种压实度在不同荷载条件下的压缩性质,通过研究不同配比材料的应变与荷载的关系、孔隙比与配比的关系、压缩系数与配比的关系、应变与配比的关系及应变与压实度的关系,得出:建筑垃圾再生材料的变形随着荷载的增大而增大,不同的压实度会使各配比的孔隙比的峰值有所不同,砖渣的含量对建筑垃圾再生材料压缩性能有较大影响,在进行现场施工时,应注意控制砖渣含量。     

交通运价比价关系分析

<正> 交通运输价格在整个国民经济价格体系中是一个相对独立的体系。在国民经济发展的一定时期内运输市场规模是一定的,各种交通运输方式存在可替代性,所以,各种运输方式运价比价关系是客观存在的。笔者的观点是:各种运输方式运价比价有其自身的规律;我们可以掌握比价关系来引导运价结构性调整,但并不能人为地规定比价关系;各种运输方式之间的合理比价关系最终是由市场供求关系确定的。 一般认为交通运输价格比价关系分为三个层次:一是交通运价与社会商品价格总水平之间的关系;二是各种运输方式之间的比价关系;三是同一运输方式内部不同对象、运输条件和运输质量的比价关系。多年以来,运输和价格主     

语录·智慧

一个人最美的状态,那道彩虹般的上升弧线,一定是在奋斗期。创业的人最精神,成名前的品牌质量最好,未确定关系的恋爱关系最灼热。——作家黎戈     

我国公路水路交通固定资产投资排行

中国民航局局长李家祥在全国民航机场工作会议强调,围绕机场公共设施定位,要统筹处理好五大关系,进一步促进机场又好又快发展。首先,进一步加大机场建设发展投资力度,要统筹处理好中央和地方两个积极性的关系。第二,进一步促进机场管理机构由经营性向管理型转变,要统筹处理好公共基础设施定位和经营收益的关系。第三,进一步提高机场安全服务水平,     

空间平均速度与时间平均速度关系模型验证

本文利用北京交通现状数据对国外已提出的关系模型进行验证,并在此基础上,提出符合北京市交通实际的空间平均速度与时间平均速度关系模型。     

Space,money, life-stage,and the allocation of time

Demographic, socioeconomic, seasonal, and scheduling factors affect the allocation of time to various activities. This paper examines those variables through exploration of the 1990 Nationwide Personal Transportation Survey, which has been inverted to track activity duration. Two key issues are considered. First, how much can activity duration and frequency explain travel duration? The analysis shows activity duration has positive and significant effects on travel duration, supporting recent arguments in favor of activity based models. Second, which recent trend is the main culprit in the rise in travel: suburbanization, rising personal incomes, or female labor force participation? This paper examines the share of time within a 24-hour budget allocated to several primary activities: home, work, shop, and other. The data suggest that income and location have modest effects on time allocation compared with the loss of discretionary time due to working.

     

Creative nodes,logistical networks,and the future of the metropolis

A paradigmatic shift away from traditional quantitative methods towards qualitative dynamic analysis is proposed in order to fully comprehend the future of the metropolis. Over the last millennium the great structural changes of production, location, trade, culture and institutions have most likely been triggered by slow but steady changes to those logistical networks which are responsible for the movement of key factors of production. Nonlinear dynamic methods such as catastrophe theory and synergetics can help to provide the necessary analytical insights. Creativity and accessibility to logistical networks are portrayed as important catalysts of qualitative change. requests for offprints     

Model,process, technique,and the good thing

The paper unpacks the planning process into its component parts: model, process, technique, and goals—the “good thing”. The paper advances the concept that planning, policy-making, and organizational restructuring can be analyzed under the same framework. Each of the four components is described and reductionist examples are presented to clarify the intention and to illustrate the technique that the transport analyst teams employ in their work. The examples cover both successes and failures. They point toward the enormous scientific task ahead for planning to become meaningful and relevant to the problems of today. Finally, in the frame of the willingness to pay, the paper puts forward a case for an institutional framework for a financially autonomous road administration. Similarly organized, administered, and managed entities are relevant also for other transport modes.

Walking frequency, cars, dogs, and the built environment

To explain walking propensity or frequency, empirical studies have generally used two sets of explanatory variables, namely, socio-demographic variables and built environment variables. They have generally shown that both socio-demographic characteristics and built environment characteristics are associated with walking propensity. We examine the traditional walkability variables that encompass density, mix of uses, and network connectivity in New Jersey, using a statewide sample including an oversample of Jersey City. We estimate a two-stage least squares model using a conditional mixed process that combines an ordered probit model of walking frequency in the second stage based on a truncated regression of car ownership in the first stage. Our results show that built environment variables have some small effects, mainly from better network connectivity associated with increased walking frequency. One of our key findings is that built environment features also work indirectly via how they influence car ownership. In general, we find sufficient evidence that suggests fewer cars are owned in areas with more walkable built environment features. The other key variable that we control for is whether a household owns a dog. This also proved to be strongly associated with walking suggesting that dog ownership is a necessary control variable to understand the frequency of walking.     

广西南宁市五象大道立交刚架桥顶推工艺

南宁市五象大道立交桥桥型为刚架结构,以高速公路中线为中心线,分为A、B两幅进行单独预制顶推就位施工。文章对该钢架顶推施工原理及工艺流程进行了介绍。     

41年光荣我见证

摆在您面前这本<运输经理世界>杂志是经过四十一年风风雨雨成长起来的<公路运输文摘>杂志的改版.今天是一个特殊的日子,她迎来了生命中一个重要里程碑第300期的出版.     

用最好的技术贴紧需求——专访Intermec(易腾迈)公司中国区总经理王敏

三年之内做到全行业最好 记者:贵公司自成立以来,一直引领着自动识别技术的发展方向.请问贵公司的自动识别技术及RFID设备能为国内的物流、运输企业带来怎样的实惠?     

Exploring the links between personal networks, time use, and the spatial distribution of social contacts

Although the study of the role of the social context in travel behavior and activity patterns has recently gained attention, the empirical evidence supporting the relationship between social networks and the temporal and spatial characteristics of social activities is still limited. With this motivation, this paper studies the link between “longer term” (social networks) and “shorter term” (social activities) social decisions, by exploring the intertwined relationship between the individuals’ personal networks attributes, and the spatiotemporal characteristics of their daily social activities. The paper contributes to the literature by adding two key aspects to the study of the role of social networks on travel behavior: the social networks’ structure, and the spatiality of all individuals participating on the social activities. Based on data which link people’s personal networks and time use, and using a structural equation modeling approach, the paper studies the influence of individual and interactional attributes on the duration, distance, and number of people involved in social daily activities. The results show that aspects such as tie social closeness, gender and age similarity, and network density, help to understand social activity duration and distance, complementing traditional socio-demographic aspects such as income, occupation, and accessibility to services. In this way, socio-demographic attributes are not enough to explain the spatiotemporal dimension of daily activities which makes necessary to include variables related to the social context to explain with a higher level of accuracy both the duration and distance traveled to the activity.     

广西百色华村特大桥主桥上构施工方法

文章介绍了广西百色华村特大桥在高墩搭设支架施工的情况下,采用索道安装挂篮运输施工材料等施工方法,为该桥梁建设降低施工成本、加快施工进度,确保施工安全打下了良好的基础,同时为陡峭复杂的山区地形及深水区更大跨度的桥梁施工提供参考与借鉴。