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21.
In a survey of 1,402 current and potential cyclists in Metro Vancouver, 73 motivators and deterrents of cycling were evaluated. The top motivators, consistent among regular, frequent, occasional and potential cyclists, were: routes away from traffic noise and pollution; routes with beautiful scenery; and paths separated from traffic. In factor analysis, the 73 survey items were grouped into 15 factors. The following factors had the most influence on likelihood of cycling: safety; ease of cycling; weather conditions; route conditions; and interactions with motor vehicles. These results indicate the importance of the location and design of bicycle routes to promote cycling.  相似文献   
22.
A new approach in recognizing travel mode choice patterns is proposed, based on the Support Vector Machine classification technique. The tour-based travel demand dataset that is analysed is for New York State, derived from the 2009 U.S. National Household Travel Survey. The main features characterizing each tour are the means used, travel-related variables and socioeconomic aspects. Results obtained demonstrate the ability to predict to some extent, in real settings where car use dominates, which tours are likely to be made by public transport or non-motorized means. Moreover, the flexibility of the technique allows assessing the predictive power of each feature according to the combination of travel means used in different tours. Potential applications range from activity-based travel choice simulators to search engines supporting personalized travel planners – in general, whenever ‘best guesses’ on mode choice patterns have to be made quickly on large amounts of data prejudicing the possibility of setting up a statistical model.  相似文献   
23.
The operation of a demand responsive transport service usually involves the management of dynamic requests. The underlying algorithms are mainly adaptations of procedures carefully designed to solve static versions of the problem, in which all the requests are known in advance. However there is no guarantee that the effectiveness of an algorithm stays unchanged when it is manipulated to work in a dynamic environment. On the other hand, the way the input is revealed to the algorithm has a decisive role on the schedule quality. We analyze three characteristics of the information flow (percentage of real‐time requests, interval between call‐in and requested pickup time and length of the computational cycle time), assessing their influence on the effectiveness of the scheduling process.  相似文献   
24.
The aim of the paper is to describe and verify a numerical model for the simulation of the dynamic behaviour of a tilting body railway vehicle, with particular attention to the curve negotiation conditions. In the model the dynamics of the tilting active control devices are reproduced, combining the numerical mechanical model of the vehicle with the control software used on the real vehicle. In order to validate the numerical simulation model, numerical results and experimental ones, from both a test rig and out-door tests, were compared.  相似文献   
25.
This article uses the Central Coast region of California as a case study to examine the challenges of protecting coastal ecosystems near areas of intensive agricultural production. Coastal water quality and biodiversity are greatly impacted by regional land use. Agricultural land use can have significant impacts on water quality through erosion and the runoff of agricultural chemicals. While the Central Coast region of California is a center for intensive agricultural production, it is also home to the largest marine sanctuary in the United States. This combination has resulted in intensive efforts from government agencies and conservation organizations to reduce pollution associated with agriculture. Efforts have focused on education and incentives, but are recently facing increasing challenges stemming from new standards created by the produce industry in response to food safety concerns. Personal interviews with crop growers were used to explore these challenges and to better understand the range of possible environmental impacts resulting from new food safety standards. Results indicate that substantial management changes are taking place that are likely to impact regional water quality and wildlife. This case study also explores the role of policy networks in shaping management decisions and illustrates how certain approaches to addressing agricultural pollution may be vulnerable to external policy changes.  相似文献   
26.
Dynamic Interaction of Railway Systems with Large Bridges   总被引:11,自引:0,他引:11  
In this paper have been described

- railway runability problems on large span bridges;

- the state-of-art of the methodologies adopted for a systematic analysis of the dynamic behaviour of railway vehicles running on a deformable structure, with particular reference to large span suspension bridges;

- some meaningful experimental and analytical results, related to railway runability of large span bridges.  相似文献   
27.
东冠康明斯发动机有限公司日前宣布,原东风康明斯副总经理黄乃绪正式就任东风康明斯总经理.原康明斯涡轮增压技术系统中国区总经理兼无锡康明斯涡轮增压技术有限公司总经理马天龙(Mark O Connor)出任东风康明斯常务副总经理.  相似文献   
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