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101.
This paper presents a hybrid discrete choice-duration model for work activity scheduling with interactions between workers in a multiple-worker household. The model operates in discrete space with a fine level of temporal resolution. The key innovative feature of the model is the introduction of intra-household interactions through worker schedule synchronization mechanisms. The model was estimated based on a large Household Travel Survey from the San Francisco Bay Area. The estimation results confirmed that individual work schedules for workers in a multiple-worker household are subject to strong synchronization and should be modelled jointly rather than independently. In particular, workers in the same household tend to align their schedules and create time window overlaps for joint activities before and after work. Relative strength of the synchronization mechanisms proved to be a function of the person characteristics and household composition.  相似文献   
102.
This paper discusses the European Maritime Safety Agency (EMSA). Through a chronological reconstruction, the study looks at the events that lead to the official birth of the Agency in 2003 and how it developed to its current state. The conceptual framework draws from cognitive policy analysis, a French political science perspective related to new institutionalisms. This approach emphasizes the role of the actors' own representations of their sector and the ways they fit within the socioeconomic system as a whole. This highlights the evolution of the stakeholders' positions and influence throughout the development process. Findings suggest that although considerable discrepancies between European representatives and those of the shipping industry were present in the context leading to EMSA's creation, the Agency has now established a working consensus confirming a greater implication of European authorities in the regulation of international shipping. The work also suggests that a greater attention to plays of power among stakeholders and how they translate in their representations could be pertinent to strengthen research in shipping policy.  相似文献   
103.
Abstract

In this paper we carry out a thorough review of the current research related to the benefits and costs arising from the implementation of longer and heavier vehicles (LHVs). From this review we concluded that despite the many studies available, little has been said about the sensitivity of the benefits and costs to the ultimate performance of the key variables related to the evolution of the economy, road transport performance, safety, and so on. In order to fill this gap, we have designed a sensitivity approach based on a cost benefit analysis tool to determine which variables demonstrate the greatest influence on the benefits and costs stemming from the implementation of LHVs. In order to test the methodology, we have used it in an analysis of the Spanish trunk network. The results show that the benefits of LHVs for society are significant. Even in the least favorable scenario, the economic benefits are greater than €3500 million over 15 years, and the environment enhanced as well, for CO2 emissions are reduced by 2 Million tonnes. Overall we noted how the results are not very sensitive to the evolution of key variables in determining the final outcome. However, we found that the variables that have the greatest affect on the final benefit, such as traffic growth and social discount rate, depend basically on the performance of the overall economy. Moreover, the private cost for haulers seems to be more important in determining the final benefit than externality costs.  相似文献   
104.
Abstract

This paper reviews the incentive structure of concession contracts in several Latin American transit reforms. It also presents a conceptual analysis of the optimal design of concession contracts. The conceptual discussion and case studies reviewed indicate that payment to operators should be linked to operational variables and that some demand risk should optimally be transferred to operators. Performance standards linked to fines and penalties are not sufficient to guarantee good quality of service, particularly in citywide reforms and where institutional capacity ― in terms of size, experience and expertise of staff ― is lacking and regulatory processes are slow, bureaucratic and cumbersome. This review may be useful for policy-makers designing transit reforms in other countries. The policy lessons of the paper are particularly relevant to cities in the developing world but they are also important for reforms in other countries.  相似文献   
105.
Abstract

The economics literature offers many examples of studies of the economic impact of transportation infrastructure such as highways, ports, and airports; however, little attention has been paid to other types of infrastructure such as logistics platforms. This article is a first assessment of the economic effects of the largest logistics platform in Europe – PLAZA, the Zaragoza Logistics Platform – located in Spain. More precisely, this paper analyzes the economic significance of PLAZA on the economy of the Aragon region where it is located. The methodology is based on the application of input–output analysis to the final demand of logistics platform-based companies in a manner that is similar to well-established studies of the economic impacts of tourism on tourist expenditure. This makes it possible to quantify the various levels of economic effects (direct, indirect, and induced) in terms of jobs, salaries, and wages, turnover, gross operating surplus (GOS), and gross value added (GVA). The conclusions reveal the economic importance PLAZA has for the regional economy of Aragon, representing just over 2% of total GVA and 3% of turnover.  相似文献   
106.
氢燃料内燃机技术现状与发展展望   总被引:9,自引:0,他引:9  
刘福水  郝利君 《汽车工程》2006,28(7):621-625
介绍了氢气及氢燃料内燃机的特点及氢燃料内燃机的技术现状。通过对比分析指出氢燃料内燃机既可以采用清洁可再生能源,又可以充分利用现有的庞大工业体系,是实现氢气经济的现实途径。  相似文献   
107.
Peter 《世界汽车》2007,(1):38-41
田在美国全面改进了7座高级SUVAcuraMDX。第二代AcuraMDX配备最大输出功率为223kW(6000r/rain)的V型6缸发动机.以及可以带4轮驱动力控制的”SHAWD《SuperHandlingAll-WheeDrive)”。该车的发动机在美国市场是输出功率最高的自然吸气V6发动机。  相似文献   
108.
Allahviranloo  Mahdieh  Bonet  Thomas  Diez  Jérémy 《Transportation》2021,48(3):1125-1148
Transportation - Historically cities are formed to provide interaction and communication opportunities for communities. As cities become smarter, new forms of interactions are formed and the...  相似文献   
109.
This papers examines the reasons for the shipping industry's general failure to exploit the enormous capital raising potential offered by the world's major security markets. The basic reason put forward is one of joint ignorance and lack a of communication. On the one hand shipping perceives the market as being unsympathetic to its requierments. On the other hand, the Stock market assess it as a minor activity and this is combined with a presumption of industrial instability. An analysis of recent initial public offering of equaity options in shipping highlights the inadequacy of companies who have ventured that way. In particular it is pointed out that shipping companies who embark on such a course must not forget that equaity is, at one end the same time, the cheapest and the most expensive money which they can raise. There is a further underlying problem for the industry, which is that market capital raising neccessiates the loss of personal control.  相似文献   
110.
The impact of a port on its local economy: the case of Plymouth   总被引:1,自引:0,他引:1  
It has been suggested in two potentially influential documents that the development of ports could be an important tool of regional economic growth in areas such as South West England. This proposition is analysed in this article by detailed examination of the case of Plymouth, one of the areas in the region for which port development has been mooted. It is concluded that the Plymouth evidence suggests that it is easy to exaggerate the existing and potential role of ports in the regional development process. Ports are not big employers of labour and are no longer the inter-related industrial complexes that they once were. In most cases, therefore, they serve industry in areas distant from their own.  相似文献   
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