Redefining activity types: Who participates in which leisure activity?

This paper analyzes the activity choices of individuals and the links between socio-demographics, daily schedules and activity attributes using a new activity choice framework. Activities are first clustered into groups based on their salient attributes, such as duration, frequency, flexibility, planning times, and number of involved persons, rather than their functional types (work, leisure and household obligations), using a K-means cluster technique. This led to the creation of several new activity groups such as “long, temporally fixed, personally flexible activities”, “short and flexible activities”. These activity groups form the choice set for the mixed logit activity choice modeling structure developed for the leisure activities in the second part of the paper. The model results reveal the significant relationships between socio-demographics, temporal characteristics, and characteristics of the schedules on leisure activity choice. The results demonstrate how changing demographics and other activities in individuals’ schedules may affect the nature of the leisure activities and present the substitution and complimentary effects that these new activity groups have on one another.     

瞄准交通强国建设新坐标 开启海南海事发展新征程

《交通强国建设纲要》(以下简称《纲要》)开宗明义,指出建设交通强国是以习近平同志为核心的党中央立足国情、着眼全局、面向未来作出的重大战略决策,是建设现代化经济体系的先行领域,是全面建成社会主义现代化强国的重要支撑,是新时代做好交通工作的总抓手。围绕着落实《纲要》,交通运输部海事局站在统筹和引领海事发展大局的高度,提出了以"五个一流"谱写新时代交通海事新篇章的发展思路,这为我们进一步学习领会和贯彻落实好交通强国建设的目标任务,推动和提升海事高质量发展提供了基本遵循和奋斗目标。     

Analysis of the effectiveness of control measures to mitigate road dust emissions in a regional network

The effectiveness of control measures to reduce road dust emissions is analyzed using a year’s data of road dust emissions collected with a mobile sampling platform and a survey of road maintenance practices in the Lake Tahoe Basin of Nevada and California US. Attributes such as sweeping practices, anti-icing, shoulder improvement, pavement condition, trackout, and abrasive material from road segments were analyzed with a feature subset selection algorithm. Street sweeping was found to be an effective means of controlling dust emissions from roads. Road dust from dirty tertiary roads served as a continuous source of suspendable material for adjacent high-speed roads in the winter time. To be most effective, emission control strategies require that not only primary roads, but all roads be swept after snow storms to recover applied abrasive material.     

Delivering mobility as a service (MaaS) through a broker/aggregator business model

Transportation - Mobility as a service (MaaS) promises a bold new future where bundled public transport and shared mobility options (carsharing, ridesharing, bikesharing and microtransit) will...     

A socioeconomic analysis of commuting professionals

Transportation - Everyday commuting as a mobility phenomenon is well-investigated and has been the topic of many contributions. Nevertheless, the distinct determinants of the commuting...     

薄层环氧沥青混合料抗剪级配优化研究

依托桃夭门大桥钢桥面铺装大修工程实例， 对如何提高薄层环氧沥青混合料抗剪切性能进行了分析研究， 提出 EA-10_S-I中断级配设计方法， 并通过室内混合料抗剪性能试验、 路用性能检测和试验段铺装检测， 优化抗剪级配设计曲线。 研究结果表明优化 EA-10_S-I级配相对于传统 Fuller 密级配沥青混合料有更好的抗剪性能， 而疲劳耐久性则优于 FAC-10_优 级配。     

论岸电技术应用保障及规范管理

本文首先介绍了岸电技术应用背景现状及行业规范推广存在的问题.然后针对低压岸电技术安全、高效、便捷的应用推广规范化,从岸电低压供电制式、岸电电力传输、岸电电力连接接口三方面,进行了问题分析,提出了技术改造和规范管理的建议.     

可持续交通——各方观点和长期挑战

从交通研究者和实践者的角度出发,以可持续交通这一概念为中心展开讨论。可持续交通宽泛地反映了可持续发展在交通领域的原则。随着可持续性这一概念的外延逐渐扩大,在它的定义、应用和价值取向上出现了不同观点。着重讨论可持续交通,以及如何理解和运用可持续交通,包括:1)将可持续性或者可持续发展作为一个整体的概念,包括关于可持续性的不同方法和定义之间的冲突;2)对可持续交通以及交通领域对其理解的探索;3)使用指标来实现可持续性的应用。然后识别了通往可持续交通之路的若干挑战,包括缺乏清晰定义、可持续性的固有冲突、可持续发展的跨领域本质、各种工作框架和指标体系、可持续发展的政治因素和交通领域实践中的不同观点。基于在该课题上的研究积累,总结解决这些问题的工作框架,提出因地制宜、注重结果、整体的方法来解决可持续交通中的挑战。     

Influence of vehicle driving parameters on the noise caused by passenger cars in urban traffic

In this work, a sample of vehicles has been instrumented to measure of variables that influence vehicle noise emissions in Madrid. A circuit reproducing a normal travel pattern in large city is traveled by a fleet of vehicle models representing the fleets of cars in a European city. A sample of drivers covers the test track under different traffic conditions. Driving parameters and noise emitted have been recorded in each test and average values have been extracted. These data have been analyzed to define the noise emissions produced by a vehicle in real driving conditions and to identify the noisiest driving behaviors.     

Do parking requirements significantly increase the area dedicated to parking? A test of the effect of parking requirements values in Los Angeles County

Minimum parking requirements (MPRs) are the norm for urban and suburban development in the United States (Davidson et al., 2002). The justification for MPRs is that overflow parking will occupy nearby street or off-street parking. Shoup (1999a) and Willson (1995) provide cases where there is reason to believe that parking space requirements have forced parcel developers to place more parking than they would in the absence of parking requirements. However, to our knowledge the existing literature does not test the effect of parking minimums on the amount of lot space devoted to parking beyond a few case studies. This paper tests the hypothesis that MPRs bind for most land uses using data on suburban office, commercial, industrial and retail property sales from Los Angeles County using both direct and indirect approaches. Our indirect test of the effects of parking requirements is similar to the one used by Glaeser and Gyourko (2003). A simple theoretical model shows that the marginal value of additional parking to the sale price of a building should be equal to the cost of land plus the cost of parking construction. We estimate the marginal values of parking and lot area with spatial methods using a large data set from the Los Angeles area non-residential property sales and find that for most of the property types the marginal value of parking is significantly below that of the parcel area. In addition, we directly examine required and supplied parking and find that on average parking supplied is quite close to the required amount.