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51.
Richard Burroughs 《Maritime Policy and Management》2005,32(3):315-328
Innovation, organizational capabilities, and environmental values combine to determine institutional change for a major marine port. This conceptual framework is applied to the case of dredged material management for the Port of New York and New Jersey. During the century under review, the institutional setting has changed significantly with: (1) environmental considerations moving from nearly irrelevant to central: (2) the number of interests and organizations increasing; and (3) the decision processes becoming far more complex. Ultimately, the new institutional setting influences organizations and individual decisions. As a result of the changes, the practice of dredged material disposal in ocean waters has been limited based on the level of bioaccumulation of selected contaminants. In response to institutional changes, ports requiring deepened channels must rapidly innovate to meet new environmental obligations for material disposal in order to enhance organizational capabilities necessary to maintain competitive advantages in maritime commerce. Successful marine ports will anticipate and meet new societal expectations related to the environment as a condition for continued legitimacy. Collectively these changes imply that ports have moved beyond a carefully circumscribed mission of transportation and economic development to that of a prominent user of coastal space with broad obligations to the public. 相似文献
52.
Several issues concerning the implementation and operation of high-speed rail service in the Detroit-Chicago corridor are identified and discussed in this paper. The primary concern is whether such a service is likely to be attractive enough to induce the private sector to provide it. While the outlook for private operation appears pessimistic, consideration of a broader range of potential benefits (e.g., direct and indirect employment) may justify public involvement and investment. 相似文献
53.
David Browne Bernadette ORegan Richard Moles 《Transportation Research Part D: Transport and Environment》2008,13(5):315-322
The objective of this paper is to compare the ecological footprint for travel-commuting patterns for the residents of an Irish city-region, that is Limerick city-region, in 1996 and 2002. Scenario building, based on ecological footprint analysis, is used to estimate the impact of different policy choices for 2010. The optimal policy mix for sustainable travel is proposed and consists of a mix of reduced demand through travel demand measures, better spatial planning and technological improvements in fuel economy. 相似文献
54.
There is growing interest in establishing additional evidence, under the umbrella of the wider economy impacts of transport infrastructure projects, to support transport projects in general and public transport projects in particular that struggle to obtain benefit–cost ratios sufficient to gain the support of financial agencies. This paper focuses on one element of wider economy impacts, often referred to as effective economic (employment) density or employment agglomeration impacts, and another, less usually identified, social accessibility impact (SAI) which we refer to as effective social density, which in broad terms provide, correspondingly, evidence of the potential gains in work-related output (often referred to as productivity gains) and potential gains in non-work-related outputs. Both are associated with gains in individual and household benefit attributable to improved accessibility to services linked with populations and particular locations. The SAIs may capture some of the induced benefits in those jurisdictions where these are included routinely in benefit–cost analysis, and the methodology here is most appropriate to those settings where an existing calibrated demand curve may not be available. Using the proposed high speed rail (HSR) project between Sydney and Melbourne as the empirical setting, we identify economic agglomeration and social accessibility benefits for work and non-work related activity respectively. We find the former to be relatively small compared to the significant gains associated with non-work related travel activity, suggesting the greatest benefits associated with HSR, especially for those residents outside of the major metropolitan areas, will be non-work related travel activity. 相似文献
55.
This article discusses the employment of Kiribati seafarers on German owned and flagged shipping. The authors examine the origins of the German shipping industry sponsored training and recruitment programmes on the Kiribati atolls. The implications of the creation of a manorial ‘internal’ labour market for German container shipping in the South West Pacific is assessed. The impact of labour participation in the international shipping industry on Kiribati's former fisherfolk is also examined. 相似文献
56.
57.
Vassilis Kitidis Louise Tizzard Günther Uher Alan Judd Rob C. Upstill-Goddard Ian M. Head Neil D. Gray Gillian Taylor Ruth Durn Raquel Diez Jorge Iglesias Soledad García-Gil 《Journal of Marine Systems》2007,66(1-4):258
Methane (CH4) concentrations were measured in the water column, in sediment porewaters, and in atmospheric air, in the Ría de Vigo, NW Spain, during both the onset (April 2003) and at the end of (September 2004) seasonal upwelling. In addition, CH4 concentration and stable isotopic signatures (δ13CH4) were measured in porewaters, and sediment methanogenesis and aerobic oxidation of CH4 were determined in sediment incubations. Surface water column CH4 (2 m depth) was in the range 3–180 nmol l− 1 (110–8500% saturation) and followed a generally landward increase but with localised maxima in both the inner and middle Ría. These maxima were consistent with CH4 inputs from underlying porewaters in which CH4 concentrations were up to 3 orders of magnitude higher (maximum 350 μmol l− 1). Surface water CH4 concentrations were approximately three times higher in September than in April, consistent with a significant benthic CH4 flux driven by enhanced sediment methanogenesis following the summer productivity maximum. CH4 and δ13CH4 in sediment porewaters and in incubated sediment slurries (20 °C) revealed significant sediment CH4 oxidation, with an apparent isotopic fractionation factor (rc) of 1.004. Using turbulent diffusion models of air–sea exchange we estimate an annual emission of atmospheric CH4 from the Ría de Vigo of 18–44 × 106 g (1.1–2.7 × 106 mol). This estimate is approximately 1–2 orders of magnitude lower than a previous estimate based on a bubble transport model. 相似文献
58.
Efficient maritime navigation through obstructions at close range is still one of the many problems faced by mariners. The
increasing traffic densities and average cruise speed of ships also impede the collision avoidance process by reducing the
time available for decision making. This study develops a path-planning algorithm that determines an optimal navigation path
for ships in close-range encounters, using known and predicted data about the traffic and environment. An improved ship dynamic
model has also been developed to better approximate the ship movement under external influences, and the algorithm was evaluated
with a set of test cases simulating various traffic scenarios typically encountered at close range. Since the method is based
on evolutionary algorithm, the algorithm behaviours were evaluated statistically, where properties such as consistency and
practicality of the algorithm outputs are discussed. 相似文献
59.
Demand for commercial air travel has been increasing over the years and recent forecasts indicate similar future trends. New aircraft with enhanced design features are being built and entering the airline service globally. These enhancements aim to ensure continued safety, efficiency, performance and prolonged life serviceability. However, these new enhancements often neglect the impact of the changing anthropometric characteristics of the passenger. Past studies have identified increasing trends in the average weight, height and other anthropometrical and biometrical measures of people at a global scale. However, many are limited to only exploring the ramifications primarily from the perspective of passenger experience. This paper highlights the importance of considering passengers’ anthropometric characteristics from a holistic perspective and identifies gaps for future research. 相似文献
60.
A new transportation system is described. CyberTran is a steel wheel on rail system designed to travel on elevated guideways, utilizing large numbers of 6 to 20 passenger automated vehicles weighing less than 10,000 pounds. The benefits from these light weight vehicles include dramatically reduced system cost and increased passenger appeal. The system described has been prototyped and tested at the Idaho National Engineering and Environmental Laboratory, a U. S. Department of Energy Research and Development Laboratory. 相似文献