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61.
Over the past decades research on travel mode choice has evolved from work that is informed by utility theory, examining the effects of objective determinants, to studies incorporating more subjective variables such as habits and attitudes. Recently, the way people perceive their travel has been analyzed with transportation-oriented scales of subjective well-being, and particularly the satisfaction with travel scale. However, studies analyzing the link between travel mode choice (i.e., decision utility) and travel satisfaction (i.e., experienced utility) are limited. In this paper we will focus on the relation between mode choice and travel satisfaction for leisure trips (with travel-related attitudes and the built environment as explanatory variables) of study participants in urban and suburban neighborhoods in the city of Ghent, Belgium. It is shown that the built environment and travel-related attitudes—both important explanatory variables of travel mode choice—and mode choice itself affect travel satisfaction. Public transit users perceive their travel most negatively, while active travel results in the highest levels of travel satisfaction. Surprisingly, suburban dwellers perceive their travel more positively than urban dwellers, for all travel modes.  相似文献   
62.
康明斯日前联手戴克公司和美国联邦环保署(EPA),共同在美国首都华盛顿向业界展示了当前全球排放最低、功率最强而且噪音最低的6.7升涡轮增压柴油机,这款新一代发动机专为克莱斯勒公司的2500和3500型道奇公羊重型皮卡配套.  相似文献   
63.
This paper presents an innovative approach to analyzing road vehicle freight traffic that uses a dynamic panel data specification derived from a gravity model. This dynamic approach, which has recently been employed in international goods trade models in lieu of the traditional static specification, is applied to the case of Spain using data for the countrys 15 NUTS-3 regions between 1999 and 2009. Using the system general method of moments approach, we obtained significant evidence that the flow of vehicles carrying commodities by road has a strong persistence effect when controlling for unobserved heterogeneity. We also found that the quality of road transport infrastructure has a significant impact on vehicle trips. According to our findings, we suggest that this type of specification be employed in distribution models in which fixed effects and lags of the dependent variable are included to account for unobserved heterogeneity and persistence effects, respectively.  相似文献   
64.
There is a large variety of multiple driven axle vehicles. Some of the most common are the 3-axle rigid vehicles and the 4-axle articulated vehicles, which can in some cases have different steering mechanisms, adaptive suspension, etc. This last kind of vehicles usually have very complex transmission configurations. Moreover, the required torques in each of the wheels can be very different, especially when the vehicle is working in rough terrains. The aim of this work is to study and model the driveline of this kind of vehicles, when using a hydrostatic transmission, from the performance and efficiency point of view, by analysing the influence of the operating conditions in the transmission efficiency. A global model is used to quantify the power flow in each of the transmission elements and the overall performance of the entire vehicle driveline, given the operating conditions thereof. A sensitivity analysis has also been done showing the influence of vehicle speed, rolling resistance, terrain slope and hydraulic motors displacement in the overall transmission efficiency. The interest of this work is also to make a contribution to the literature in the field of global modelling of drivelines under variable operating conditions and its application to ATVs. One important aspect is the influence of different actuation requirements that occur in different wheels at the same time. The results show that the overall performance of the transmission is highly dependent on operating conditions, on the selected transmission configuration and on the used components.  相似文献   
65.
Cantillo  Tatiana  Vargas  Andrés  Cantillo  Víctor  Ramos  José 《Transportation》2020,47(5):2267-2286
Transportation - Inadequate infrastructure is recognized as an important barrier to cycling; therefore, improvements in the provision of bicycle facilities, such as bikeways, are frequently...  相似文献   
66.
Abstract

Indigenous peoples’ efforts toward environmental conservation are indivisible from their cultural identity and their social and political organizations. Indigenous resurgence, including the reinvigoration and reestablishment of Indigenous ways of living, are linked to the management, restoration, and conservation of marine and coastal ecosystems around the world. However, there remains a significant gap in the recognition and support of Indigenous governance systems in international policy discussions regarding conservation work. As a way to address this gap, we offer an analysis of marine Indigenous community-led conservation initiatives from around the world that were recipients of the UNDP Equator Prize, framed by initial research on Indigenous-led conservation in British Columbia, Canada. We highlight specific Indigenous governance strategies undertaken by such communities that foster both marine resource conservation and stewardship. The strategies we identified included practicing Indigenous traditional resource management, protection of traditional territories, Indigenous-led actions of environmental conservation, and data collection and monitoring. We also identified networking and collaboration with non-Indigenous supporters, as was reinvestment into education and capacity-building within the community. We conclude with concrete policy suggestions drawn from these cases that can help strengthen the leadership and self-determination of Indigenous peoples on local resource and environmental issues, and aid in much broader conservation efforts globally.  相似文献   
67.
Abstract

This paper computes the cost of traffic congestion in the city of Antofagasta in Chile. A microsimulation is implemented where all the agents of the system travel across the transport network. The congestion cost is computed through the aggregation of the opportunity cost of people waiting within the transport system, as a consequence of traffic congestion. Monte Carlo experiments produced an approximated congestion cost of US$1.02 million during a typical working day. Moreover, the simulation provides useful information about the average traveling time for the 14 districts of the city.  相似文献   
68.
Abstract

Public transport policy in the Madrid Metropolitan Area is often deemed as a success. In 1985, an important reform was carried out in order to create a new administrative authority to coordinate all public transport modes and establish a single fare for all of them. This reform prompted a huge growth in public transport usage, even though it reduced the funding coverage ratio of the transport system. Since then, Madrid’s public transport system has been undergoing an increasing level of subsidization, which might jeopardize the financial viability of the city public transport system in the future. In this paper, we present a detailed analysis of the evolution of the public transport funding policy in Madrid in recent years. We found that the increasing level of subsidy can hardly be explained on the basis of equity issues. Moreover, we claim that there is still room for a funding policy that makes the efficiency of the system compatible with its financial sustainability.  相似文献   
69.
Abstract

Since 1990s the liner shipping industry has faced a period of restructuring and consolidation, and been confronted with a continuing increase in container vessel scale. The impact of these changes is noticeable in trade patterns, cargo handling methods and shipping routes, in short ‘operations’. After listing factors influencing size, growth in container ship size is explained by economies of scale in deploying larger vessels. In order to quantify economies of scale, this paper uses the liner service cash flow model. A novelty in the model is the inclusion of +6000-20-foot Equivalent Unit (TEU) vessels and the distinction in costs between single and twin propeller units on ships. The results illustrate that scale economies have been – and will continue to be – the driving force behind the deployment of larger container vessels. The paper then assesses the link between ship size and operations, given current discussions about the increase in container vessel scale. It is found that (a) ship size and operations are linked; (b) optimal ship size depends on transport segment (deep-sea vs. short-sea shipping, SSS), terminal type (transhipment terminals vs. other terminals), trade lane (East-West vs. North-South trades) and technology; and (c) a ship optimal for one trade can be suboptimal for another.  相似文献   
70.
装备两台康明斯-水星QSC型8.3升540马力全电控船用发动机、燃用B100生物柴油(100%的生物柴油)的“环球竞赛号(Earthrace)”高速环保机动船6月27日抵达西班牙萨贡托港,结束了为期60天23小时49分钟的环球航程,从而打破英国高速船“大东电报号(Cable&Wireless)”十年前创下的74天20小时58分钟纪录。  相似文献   
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