Influence of the residential and work environment on car use in dual-earner households

This paper analyses whether the decision to commute by car is influenced by built environment characteristics of residential neighbourhoods and, more especially, of work locations, taking into account interdependencies between household partners. It shows that the residential environment only affects car use among single-earners. Conversely, for all commuters, but in particular for dual-earners, characteristics of the work location affect whether they commute by car. Even in dual-earner households with two cars, work environment plays a role. We found that in cases of dual-earners with only one car, the partners with the longest commuting distances and the lowest density work locations are most likely to commute by car. Moreover, in households with young children, men are more inclined to leave the car at home. Other features relating to work also affect car commuting, including work flexibility and, especially, possession of a company car. We conclude that future policies aimed at reducing car use should place greater focus on work factors.     

基于交通环境承载力的城市交通容量的确定方法及应用

基于交通环境承载力的城市交通容量是衡量交通可持续发展的一个关键定量指标,研究城市交通容量的基本理论和确定方法具有十分重要的理论和现实意义。在对各国交通容量的研究现状进行分析的基础上,将交通容量划分为微观交通容量和宏观交通容量,并给出了相应的定义。然后从系统的观点出发提出了一种新的基于交通环境承载力的城市交通容量确定方法并进行了应用。应用结果表明:该方法能够有效地确定城市交通容量,从而为政府部门进行城市交通规划、衡量城市交通可持续发展提供科学决策依据。     

The impacts of built environment on home-based work and non-work trips: An empirical study from Iran

This paper aims to explore the impact of built environment attributes in the scale of one quarter-mile buffers on individuals’ travel behaviors in the metropolitan of Shiraz, Iran. In order to develop this topic, the present research is developed through the analysis of a dataset collected from residents of 22 neighborhoods with variety of land use features. Using household survey on daily activities, this study investigates home-based work and non-work (HBW and HBN) trips. Structural equation models are utilized to examine the relationships between land use attributes and travel behavior while taking into account socio-economic characteristics as the residential self-selection. Results from models indicate that individuals residing in areas with high residential and job density, and shorter distance to sub-centers are more interested in using transit and non-motorized modes. Moreover, residents of neighborhoods with mixed land uses tend to travel less by car and more by transit and non-motorized modes to non-work destinations. Nevertheless, the influences of design measurements such as street density and internal connectivity are mixed in our models. Although higher internal connectivity leads to more transit and non-motorized trips in HBW model, the impacts of design measurements on individuals travel behavior in HBN model are significantly in contrast with research hypothesis. Our study also shows the importance of individuals’ self-selection impacts on travel behaviors; individuals with special socio-demographic attributes live in the neighborhoods with regard to their transportation patterns. The findings of this paper reveal that the effects of built environment attributes on travel behavior in origins of trips do not exactly correspond with the expected predictions, when it comes in practice in a various study context. This study displays the necessity of regarding local conditions of urban areas and the inherent differences between travel destinations in integrating land use and transportation planning.     

Meta-analysis of the relationships between space syntax measures and pedestrian movement

ABSTRACT

Ample research has been conducted investigating the built environment impacts on pedestrian movement (PM). A clear division is also evident in the literature on this topic: one group tends to use geographic measures (metric distance) of the environment to explain pedestrian behaviour; the other group uses syntactic measures (visual distance). Many review articles have been published on the former. However, relatively little is known about the effect size (ES), directions, and consistency of syntactic measures in explaining PM. This paper fills this gap through a meta-analysis of published and unpublished studies on this topic spanning over 1975–2016, and answers the following five research questions: (a) What are the different measures used in the space syntax literature to explain PM?; (b) What are the magnitudes and directions of associations between space syntax measures and PM?; (c) Which space syntax measure has a more consistent relationship with PM?; (d) To what extent do the explanatory powers of different measures vary between their derivation methods?; and (e) What are the likely causes of variations of the reported results in prior studies? This research examined four syntactic measures (integration, connectivity, choice, and control) in a random effect model with 95% confidence interval (CI). The choice and integration measures were further investigated based on their operational approaches (topological, angular and metric). Results show that integration (ES?=?0.206, 95% CI?=?0.173–0.238, p?<?0.001), choice (ES?=?0.481, 95% CI?=?0.391–0.561, p?<?0.001), and connectivity (ES?=?0.305, 95% CI?=??0.225–0.696, p?=?0.257) measures positively influence PM with choice being the strongest predictor. Both connectivity and control (ES?=??0.001, 95% CI?=??0.117–0.115, p?=?0.990) were found to have a statistically insignificant impact. The choice and integration measures show stronger effects when derived using the angular approach (ES?=?0.493 for choice, and ES?=?0.502 for integration) compared to topological approach (ES?=?0.374 for choice, and ES?=?0.124 for integration). However, the reported results of all measures are highly heterogeneous, perhaps due to the differences in research design. The significance, magnitude, and consistency of integration and choice measures justify their relevance in built environment interventions to promote PM.     

Effect of built environment measures on trip distance and mode choice decision of non-workers from a city of a developing country,India

This paper investigates the influence of built environment measures on trip distance and walking decision of non-workers by segmenting the populace based on trip purpose, vehicle ownership, and the presence of school-going children in households. The built environment measures of home zone of individuals considered for the present analysis include zonal population density, zonal school enrolment, land use mix diversity index, and an indicator variable that captures if neighbourhoods have footpaths of adequate width available. Statistical analyses conducted on home-based trips indicate that an increase in the land use diversity of a zone has its strongest negative effect on distance travelled for participating in personal/household business activities. The non-vehicle owning group exhibit a higher tendency to walk than the vehicle-owning group for an increase in the land use diversity of zones. Further, the study suggests that school-enrolment in a zone also influences the travel decisions of non-workers in families with school-going children.     

A bibliometric analysis on trends and characters of carbon emissions from transport sector

Transport sector’s substantial contribution to global greenhouse gas emissions has made it a growing area of study and concern. In order to identify trends and characteristics of carbon emissions research in the transportation sector we conducted a Bibexcel and complex network analysis for the period 1997–2016. In addition, we identify critical themes and contributions of research articles using h-index, PageRank and cluster analysis. We report contribution of countries, authors, institutions and journals, as well as performance of citations and keywords. Co-citing situations between different countries, authors, and institutions are also analyzed using network analysis. Between 1997 and 2016 we found a rise in publications on carbon emissions in the transportation sector and increased cooperation between countries, authors, and institutions. Authors from the USA, China and United Kingdom published the most articles and articles with the highest academic influence. Tsinghua University from China is the leading institution in carbon emissions research in the transportation sector. The most widely published author and cited author is Dr. He. We conclude our analysis by analyzing keywords and trends to suggest critical topic areas of future research. The systematic approach undertaken in this study can be extended and applied to other research topics and fields.     

青藏铁路山丘坡地取土场生态恢复措施探讨

青藏铁路主体工程完工后,取土场的生态环境恢复是全线环保恢复工作的重要组成部分,恢复的目的是通过对取土场的综合治理,达到防止水土流失、防止冻融滑塌,同周围景观协调统一,并进一步达到复垦还林还草要求。本文针对青藏高原冻土地区山丘坡地取土场植被稀疏、生态脆弱的特点,进行了以工程措施为主、生物措施为辅的研究尝试,取土场恢复试验结果表明,从景观恢复、水土保持和防止冻土区的融陷、滑塌现象均取得了明显的效果。     

中国视屏显示终端职业危害研究现况

调查发现视屏显示终端操作者主诉有神经衰弱、易感冒、眼和肌肉骨骼不适。客观呈现眼视力下降，颈肩腕肌肉压痛。生殖系统调查有月经异常和先兆流产、自发性流产率增高。研究揭示，视屏显示终端室内外温差大，空气阴离子减少，臭氧很少，固定式的桌椅和不良的坐姿等是影响视屏显示终端操作者健康的主要因素。符合卫生标准的环境和工效学原则的规范化操作，可保护视屏显示终端操作者的健康。工间休息能使视力恢复，不良的健康反应得以消除。     

机车柴油机微机检测系统可靠性的研究

本文在分析机车柴油机微机检测系统工作环境条件的基础上,提出了抑制电磁干扰,提高检测系统可靠性的措施。     

中低速磁浮与轮轨交通系统电磁环境影响差异性分析

通过对中低速磁浮和轮轨交通系统的电磁发射实测数据进行深入分析,比较两者电磁参量典型数例和变化规律,得出了中低速磁浮线路和轮轨交通系统实测电磁参量在频域、时域和空间分布等方面的差异。该成果可为中低速磁浮相关标准制定和电磁干扰防护设计提供实测依据和技术支撑。