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241.
文章针对高职院校三年制教学模式下公路运输与管理人才培养的弊端,结合公路运输行业的发展实际,提出公路运输与管理专业推行“2+1”实训教学模式改革的必要性,阐述了分阶段、循环递进式的实训教学模式及实施流程,并评述了该教学模式取得的成效与存在的不足.  相似文献   
242.
Social equity is increasingly incorporated as a long-term objective into urban transportation plans. Researchers use accessibility measures to assess equity issues, such as determining the amount of jobs reachable by marginalized groups within a defined travel time threshold and compare these measures across socioeconomic categories. However, allocating public transit resources in an equitable manner is not only related to travel time, but also related to the out-of-pocket cost of transit, which can represent a major barrier to accessibility for many disadvantaged groups. Therefore, this research proposes a set of new accessibility measures that incorporates both travel time and transit fares. It then applies those measures to determine whether people residing in socially disadvantaged neighborhoods in Montreal, Canada experience the same levels of transit accessibility as those living in other neighborhoods. Results are presented in terms of regional accessibility and trends by social indicator decile. Travel time accessibility measures estimate a higher number of jobs that can be reached compared to combined travel time and cost measures. However, the degree and impact of these measures varies across the social deciles. Compared to other groups in the region, residents of socially disadvantaged areas have more equitable accessibility to jobs using transit; this is reflected in smaller decreases in accessibility when fare costs are included. Generating new measures of accessibility combining travel time and transit fares provides more accurate measures that can be easily communicated by transportation planners and engineers to policy makers and the public since it translates accessibility measures to a dollar value.  相似文献   
243.
通过对复合通道相关研究的综述,总结了高、快速路复合通道的积极意义,提出复合通道建设的难点主要为通道走廊的选择与布局模式的选取、降低节点复杂程度、解决各系统间的转换需求以及施工组织复杂.并以佛山市广佛新干线复合通道为例简要介绍了上述几个难点的处理思路,最后分析了复合通道建设存在的几个要点问题,为该类型道路的建设提供一定的基础.  相似文献   
244.
This paper considers the length of time that parents are willing to travel to an existing or new job. Using data for over 12,000 parents it finds that many characteristics were associated with being less likely to be willing to travel to work for at least an hour (roundtrip). These include: being a women, those out of work, having children under 5, being a lone parent and using formal childcare. Professionals and associate professions were more willing to travel for longer periods. In terms of location, those in accessible small towns and rural areas were willing to travel more than those in larger urban areas and those in remote rural areas willing to travel most. Policy implications are also set out.  相似文献   
245.
采用大型、先进的滑模摊铺技术能提高水泥混凝土路面的整体质量,确保水泥混凝土路面的平整、密实以及行车舒适性。基于实践经验,就如何提高水泥混凝土路面滑模摊铺施工中平整度指标提出几点建议,以供参考。  相似文献   
246.
当前各类高职院校Rhino建模软件课程普遍专注于“教、学、做”一体化教学模式,但是本教学模式在实施过程中,由于“教、学、做”一体化、Rhino建模软件、高职院校学生三者都有其个性化特征,因此“一体化”这种优越的教学模式,不能不加分析的拿来就用。本文提出了多种方法相结合的立体化模式,与实际应用学科的教学实践相结合来辅助和完善一体化教学模式。此思路对于高职院校计算机辅助设计类课程教学方法的改革,是一种积极的探索。  相似文献   
247.
There is increasing interest in understanding and achieving changes in travel behaviour, but a focus on individual behaviour change may overlook the potential for achieving change via transformation at the levels of institutions, cultures and societies – the domains of sociological inquiry. In this paper, we review sociological contributions to the literature on travel and ‘mobilities’. We summarise four key themes which supplement or contradict arguments made in mainstream transport debates on behaviour change. The first involves focusing on travel ‘practices’ as social entities with dynamics of their own, rather than on individual behaviours. The second relates to the changing natures of societies, and the implications for travel. The third explores and interprets the issue of car dependence in ways which highlight the ethical, experiential and emotional dimensions associated with car use, its symbolic role in societies increasingly concerned with consumption, and its differing roles within different cultures. Finally, the ‘new mobilities paradigm’ highlights issues such as the increasing links between travel and new technologies, and the primacy of social networks in influencing travel decisions. These themes emphasise the importance of understanding the broader contexts in which travel choices are made. In particular, the implication is that the creation of more sustainable travel patterns will require changes at a range of social levels, not simply in individual behaviours, and that changes to transport will inevitably be linked with, and influenced by, broader changes in the values and practices developed by societies as a whole.  相似文献   
248.
This paper presents an alternative planning framework to model and forecast network traffic for planning applications in small communities, where limited resources debilitate the development and applications of the conventional four-step travel demand forecasting model. The core idea is to use the Path Flow Estimator (PFE) to estimate current and forecast future traffic demand while taking into account of various field and planning data as modeling constraints. Specifically, two versions of PFE are developed: a base year PFE for estimating the current network traffic conditions using field data and planning data, if available, and a future year PFE for predicting future network traffic conditions using forecast planning data and the estimated base year origin–destination trip table as constraints. In the absence of travel survey data, the proposed method uses similar data (traffic counts and land use data) as a four-step model for model development and calibration. Since the Institute of Transportation Engineers (ITE) trip generation rates and Highway Capacity Manual (HCM) are both utilized in the modeling process, the analysis scope and results are consistent with those of common traffic impact studies and other short-range, localized transportation improvement programs. Solution algorithms are also developed to solve the two PFE models and integrated into a GIS-based software called Visual PFE. For proof of concept, two case studies in northern California are performed to demonstrate how the tool can be used in practice. The first case study is a small community of St. Helena, where the city’s planning department has neither an existing travel demand model nor the budget for developing a full four-step model. The second case study is in the city of Eureka, where there is a four-step model developed for the Humboldt County that can be used for comparison. The results show that the proposed approach is applicable for small communities with limited resources.  相似文献   
249.
刘黎  张平  王唤龙  杨昌宇 《隧道建设》2020,40(Z2):188-195
为了满足高黎贡山隧道竖井施工任务要求,综合隧道所处环境及竖井能力需求,按照竖井井口、井筒、井下3方面统筹考虑的总体设计思路,提出高黎贡山隧道1号竖井设计关键问题的解决方案: 1)根据井口地形、地貌条件及提升设备、井口车场布置要求,合理布置井口场坪; 2)根据竖井功能定位,竖井宜采用主副井模式; 3)根据井下施工的出渣量、材料数量、人员进出量等综合考虑竖井断面尺寸; 4)当地质条件、水文地质条件允许时,竖井宜采用短段掘砌混合作业法施工,设置模筑混凝土井壁; 5)竖井提升设备宜按井下施工期间的要求考虑,建井期间各设备之间能力应匹配; 6)竖井施工能力应满足井下施工期间出渣、进料要求,并留有富余; 7)井底车场应结合运输方式及进料、出渣等功能要求确定; 8)竖井安全保障应首要解决地下水问题。目前高黎贡山隧道1号竖井主井已完成建井,结果表明铁路隧道竖井按照以上设计方法及思路是可行的。  相似文献   
250.
采用基于经验模态分解(EMD)的本征模态函数(IMF)分析法和对比实验法研究了有自由液面的陷落式圆腔的流噪声,实验流速为0.4m/s~2.0m/s,间隔0.2m/s。实验发现当流速为0.4m/s~0.6m/s时,腔内液体有明显的振荡现象,其表现形式为液体沿腔内深度方向的大幅上下运动,称为“活塞(Piston)”现象。当流速大于等于0.8m/s时,腔内无振荡现象出现。通过对背景噪声和腔流噪声的本征模态函数作对比分析,得到了腔内流噪声的特性。  相似文献   
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