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1.
Through the use of a profit-maximizing continuum approximation model, this paper systematically analyzes the development and structure of informal transit systems as a function of the network, user, and modal characteristics. This study examines the evening commute problem along a linear corridor where passengers originate uniformly from a central business district and have destinations uniformly distributed along the corridor. Informal transit drivers who are profit-maximizing will be compared against the traditional case of coordinated, government service that aims to maximize the total welfare. Policies, such as fare regulation and vehicle licensing schemes, will be presented to help rationalize informal transit service using a government-operated service as the baseline.  相似文献   

2.
Over the preceding decade, the World Bank committed about US$7.5bn in loans for urban transport projects in its client countries, involving total project costs of nearly US$13bn. Projects are designed by the client city/national governments and the World Bank in an interactive, give-and-take process. As is common in development finance, urban transport projects entail an investment program and a set of policy and institutional initiatives. A majority of Bank-funded operations in this period focused on public transport modes. A clear and overarching strategic thrust is evident, favoring private delivery of services with a strong public role through city-specific regulatory agencies. Depending on the context, projects involved efforts to introduce private operators and competition into an all-public set-up, or tighten up weakly regulated, “informal” public transport markets. A notable feature of many projects in the latter context is the use of investments in bus rapid transit infrastructure to reach multiple goals: improve transport services, maintain affordability for low-income passengers, attract new passengers, reduce negative environmental impacts, and leverage complementary reforms of policies and institutions. The Bank’s program in China, unique in its local context of a dynamic urban society moving away from a near-universal reliance on bicycles, initially did not focus on public transport but on urban roads and traffic management. Towards the end of the last decade, the motorization process and the outlook of decision makers entering a more mature stage, projects in China started to converge towards what the rest of the Bank’s program was doing – searching for a more sustainable path to urban transport development.  相似文献   

3.
Recently, the number of foreign tourists to Korea via cruise ships has increased dramatically. We attempted to estimate the shore excursion expenditure function during cruise tourism in Korea. To this end, we collected data from a survey of foreign tourists who visited Korea via cruise ships and conducted the ordered probit model with sample selection to correct for the sample selection bias. Statistical tests indicate that the sample selection model provides unbiased estimates of the ordered probit model. The estimation results reveal that the coefficients of the experience of visiting Korea, job status, annual income, and nationality have statistically significant relationships with shopping expenditure. Further, it is likely that Chinese and Japanese passengers spend more money on shopping than passengers from other countries. This study is expected to provide the Korean government and port authorities with useful information for targeting passengers with high shore excursion expenditure. From a management perspective, the results of this analysis will enable cruise operators to design shore excursion programs that meet travelers’ needs.  相似文献   

4.
应用重整化群κ-ε紊流模型,分别计算并比较了非空态与空态空调列车室内空气三维紊流流场与温度场的分布特性.采用MonteCarlo法分析计算了太阳透射辐射和壁面间的辐射在车室内各固体壁面引起的附加热流变化,并以此作为能量方程的附加源项;对旅客产生的热负荷分别采用平面分布与空间分布处理方式,对比分析了采用不同热负荷分布方式对空调列车客室内三维空气流场与温度场分布的影响.研究分析表明:不同的热源处理方式对客室内流场与温度场有较大的影响.最后,实验验证了采用数值模拟手段研究非空态空调列车室内气流组织的可靠性,为空调列车室内舒适环境的优化研究提供了依据.  相似文献   

5.
Transit textbooks and engineering manuals indicate that the capacity of Bus Rapid Transit –BRT – systems does not exceed 20,000 passengers per hour per direction. The implementation of the TransMilenio BRT System, in Bogotá, Colombia, showed that the systematic combination of multiple platforms at stations, overtaking lanes, level boarding, prepayment, large buses with multiple doors, express and local services, and traffic engineering measures at intersections, allow for very large passenger throughput. Measurements indicate actual throughput of 43,000 passengers per hour per direction with average bus occupancy of 150 passengers per articulated bus, and a commercial speed of 22–24 km/h. According to special formulas developed for the analysis of high capacity BRT corridors, the critical section of TransMilenio has a practical capacity of 48,000 passengers per hour per direction with its existing infrastructure and 150 passengers per bus – 35,000 passengers per hour per direction with 110 passengers per bus. Changes in existing infrastructure, such as additional platforms, higher capacity vehicles, non-grade facilities at critical intersections, among other improvements, may increase the capacity, speed, reliability and quality of service of the system.  相似文献   

6.
Two-sided markets are characterised by the presence of an intermediary and two groups of end-users. In the cruise market, cruise lines may play the role of intermediaries to connect the two end-users, viz. cruise passengers and cruise ports. Our research explored whether the cruise industry can be regarded as a two-sided market, starting with a theoretical modelling. The findings show that cruise lines might be hybrid intermediaries, selling their own ship-based products and services, while offering also a platform to enable the transaction between cruise passengers and cruise ports. This particular business model of a quasi-two-sided market is also reflected in the pricing scheme of cruise industry, whereby cruise ports charge an entry fee from cruise lines and port dues from cruise passengers. We illustrate an empirical analysis on the basis of the cruise market in Japan, and it provides a preliminary clue that the behaviours of cruise ports and cruise lines are consistent with our theoretical framework. The results are not convincingly significant due to data limitations, hence, the concept of a ‘two-sided market’ in the cruise industry call for further empirical research.  相似文献   

7.
A key question is whether the service quality instruments developed for other services’ industries may be used to gauge service quality perceptions in shipping. Grounded on similar studies that test the most widely used American service quality instrument, SERVQUAL, in the commercial shipping sector, this study examines its applicability in the passenger shipping realm. Based on a survey of 436 passengers in Piraeus port, SERVQUAL's five main dimensions have been checked regarding their fit with the use of Confirmatory Factor Analysis. Results support that this is a valid instrument for measuring service quality in passenger shipping besides certain considerations regarding its dimensionality. A more parsimonious two-factor model seems more applicable and should therefore be also considered. Finally, it is evident from the study that passengers place more importance to the physical than the interactive elements of service to form their overall satisfaction.  相似文献   

8.
航道承载着具有OD点对的船舶组成的交通流,航道通过能力表示航道的交通承载能力。将多级航道中各港口视为网络模型中的节点,各航段视为网络模型中的连线,考虑与航道通过能力密切相关的航道货流OD结构,建立了以任意起点港和终点港之间货流量为变量,各货流量或货物周转量之和最大为目标函数,航段通过能力、港口设计通过能力及碍航建筑物通过能力为限制条件的OD结构网络模型,来测算多级航道通过能力。  相似文献   

9.
Land development impacts of mass transit have long been studied in the developed economies. Yet relatively little is known by the outside world about the Chinese experience due to China's rather short history in the development of modern mass transit and land/property market. This paper attempts to fill the gap by presenting evidence from China, with a detailed case study of Beijing. Selecting three newly built suburban transit lines in Beijing, the study examined land development context and estimated hedonic housing price models to measure the proximity premiums associated with these three lines. The empirical evidence in Beijing, one of the first tier mass transit cities in China, shows that investments in mass transit can have significant and positive impacts on land development. Properties with transit proximity enjoy sizable price or value premiums. The study also confirms the international experience: transit impacts on land development are unlikely to occur automatically; they rely greatly on supportive regional and site conditions. Integrated planning and design for mass transit and land development are critical to expand and maximize the return of transit investments.  相似文献   

10.
A 2D advection-dispersion model, already described and validated, has been used to provide information about water trajectories, transit times, transfer factors and transfer functions in the Channel and North Sea, south of 57 ° N.It shows that a fast vein of water moves parallel to the coast and reaches the northern limit of the model in one year. Along the coast, a few dozen kilometers from this vein, transit times increase by 2–4 months.Tidal gyres in the Channel recirculate waters and dissolved elements for about 2 yr, and in all it generally takes 3 yr for a specific discharge made at La Hague to completely leave the area under study.The transfer factor was depicted and found to be of the order of 10−5 m.k.s.One utilization of the transfer function could be to predict the future evolution of water content in the months and years following a discharge in these coastal waters.  相似文献   

11.
为研究水网航道最大通过能力,从水网航道的网状拓扑结构和船舶航行的基本特点出发,以时空消耗理论为基础,建立网状航道一维、二维通过能力理论计算模型。实例计算结果表明,理论模型可以准确地计算出水网航道的理想通过能力,可以作为精确计算水网航道实际通过能力的基础模型。  相似文献   

12.
This paper presents the recent results from an ongoing analysis of the effects of high-speed naval operations on the performance, comfort, and safety of crew and passengers. A 127-m trimaran, the Benchijigua Express, which is similar in hull design to the General Dynamics Littoral Combat Ship (LCS) vessel, was investigated for motion-induced interruptions, motion sickness, and biodynamic feed-through to manual tasks. Data were obtained on two 2-hour transits per day for a total of 86 transits during February and March 2006. Survey questionnaires were obtained from nearly 2,000 passengers. The motion effects on manual dexterity were negligible, but motion sickness symptoms were reported by a majority of the passengers. The capability to manage the motion sickness issue for unadapted passengers may be important for the effective use of LCS to transport ground combatants and for Sea Basing concepts.  相似文献   

13.
In the present context of booming cruise demand, the study aims to advance the knowledge on port of call performance from cruise passengers’ perspective. The aim of this investigation was twofold: (1) to examine the structural links among port of call perceived quality–satisfaction–future intentions (revisit and word-of-mouth (WOM) behaviour); and (2) to test the moderating effect of cruisers’ motivation (push versus pull factors) to visit the port of call on the proposed structural links. Partial least squares path modelling was used to test the proposed model with a sample of 492 cruise passengers at a Mediterranean port of call. The findings revealed that port of call quality has a positive impact on port of call satisfaction, which in turn, strongly affects revisit and WOM intention. Besides, the results of the multi-group analysis indicated that the links between port of call quality–satisfaction and port of call satisfaction–WOM are moderated by cruisers’ motivation. Implications for port authorities and cruise lines are discussed.  相似文献   

14.
A model to compare three alternative forms of public transport - light rail, heavy rail and bus rapid transit - is developed for an urban network with radial lines emanating from the borders to the city centre. The theoretical framework assumes an operation aimed at minimising the total cost associated with public transport service provision, which encompasses both operator and users costs. The decision variables are the number of lines (network density) and the frequency per period for each mode. This approach has no prejudices a priori in respect of whether a specified delivery scenario is aligned with existing modal reputation. Rather, we establish the conditions under which a specific transit mode should be preferred to another in terms of the operator (supply) and user (demand) side offerings. The model is applied using data from Australian cities, suggesting that in most of the scenarios analysed a high standard bus service is the most cost-effective mode, because it provides lower operator costs (infrastructure, rolling stock and operating cost), access time costs (due to a larger number of lines) and waiting time cost (due to larger frequencies of operation). A rail mode, such as light rail or heavy rail, may have a lower total cost only if it is able to run faster than bus rapid transit, and the difference in speed is enough to outweigh the bus advantage on operator cost and access and waiting times.  相似文献   

15.
杨伟佳 《水运工程》2013,(10):263-266
基于吴淞口国际邮轮港交通组织设计,重点分析旅客到达后通关边检采用M/M/N和N-M//M/1随机排队模型的异 同点,研究了通关排队服务采用两个不同模型的体验差异,对解决排队旅客与服务机构两方面利益的最优控制问题提出了 初步解决方案。  相似文献   

16.
This paper uses individual worker and municipal information to examine privatization's influence on public transit workers' earnings and employment. OLS findings on labor earnings reveal that privatization is associated with an erosion of the public transit union premium. These labor earning findings do not change when correcting for privatization heterogeneity, as unobserved worker characteristics do not differ with differing levels of municipal privatization of public transit services. The employment findings reveal that union public transit workers are more likely to be employed in the public sector and this union-nonunion employment probability differential, declines with increasing levels of privatization. This employment result is interpreted as suggesting that labor cost savings from privatization can be derived from the enhanced employment of relatively low wage nonunion workers in the public sector of public transit services.  相似文献   

17.
全球海运的发展催生出以转运货物形式服务于周边区域和远洋运输的中转港,它们在全球贸易及运输体系中占据重要地位,形成了明显的特征格局。在中转港形成因素及分类研究的基础上,总结全球范围中转港发展格局和发展特征,探讨不同区域中转港的发展趋势。结果表明,当前全球航运格局重心在亚太地区,国际中转港主要分布在远东-西欧-北美主航线,而扼守关键区位则容易催生出中转大港。同时,未来各区域的中转港发展将随着经济全球化与国际贸易的深入发展而变动,并受船舶大型化、服务软环境等显著影响。  相似文献   

18.
This article presents a new approach for the prediction of motion sickness on ships, with a focus on high-speed craft. The methodology presented is based on a variant of the sensory conflict hypothesis and the human vestibular system. The proposed model was developed using control theory and is capable of taking account of all six degrees of freedom vessel motion for the prediction of motion sickness. Furthermore, full-scale trials were carried out onboard three different high-speed craft to measure the ship motions and consequently to analyse their effects on passengers in terms of motion sickness. Through the accumulated results, the developed model was validated and was compared with existing methods/criteria for the prediction of the incidence of motion sickness.  相似文献   

19.
针对XJ自升式平台,采用Moses软件建立平台模型,分别计算该平台在油田拖航和远洋拖航时的完整稳性以及破舱稳性。将实际拖航时的稳性情况与数值模拟结果进行对比发现,用Moses简化建模来模拟计算平台拖航稳性所产生的模型误差对最终稳性计算结果的影响较小。  相似文献   

20.
This paper describes the development of approaches to analysing the links between investment in transit and economic development. It indicates the need to bring together disparate approaches from urban economics and transportation economics to get a full understanding and uses recent results on agglomeration economies to present a more rigorous model of the wider economic benefits of transit investment. Although the evidence increasingly points towards identifiable benefits over and above those captured in conventional transport cost-benefit analysis, the chapter counsels against the assumption of simple rules.  相似文献   

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