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1.
ABSTRACT

The economic history of the U.S. illustrates how the role of many cities has been changed by being seaports or located on navigable rivers or lakes. Based on the widening of the Panama Canal in 2016, the West Coast ports that include the west coast seaports of California, Oregon, and Washington were expected to become less important, while the freight shares of the East Coast and Gulf ports would increase. By how much it has been not easy to measure or predict so far, but this study attempted to define some of the key parameters in the measurement. As well as several relevant background topics, both the demand- and supply-side versions of the National Interstate Economic Model, have been applied for the measurement of economic impacts. U.S. port authorities and policy makers at the local and national levels who respond and develop plans for coping with the new realities of the Panama Canal are able to understand the extent to which changes in shippers’ and land-mode transporters’ behaviors would undermine the logistics and the costs of their activities. Therefore, this study is important for a diverse spectrum of port development strategies in the U.S. to respond to the Canal expansion.  相似文献   
2.
Abstract

Urban waterfronts are increasingly the focus of revitalization efforts designed to enhance tourism and recreation. The evolution of urban waterfronts suggests that these resources experience distinct stages of introduction, growth, maturity, decline, and sometimes revitalization. In this paper the product life cycle is broadened to describe the evolution of the waterfront district of Galveston, Texas. Implications of the product life cycle model of urban waterfront revitalization pertain to public policy formation, “product”; development, and management response to different life cycle stages.  相似文献   
3.
Identification of optimal sites for the isolation of waste on the abyssal seafloor was performed with two approaches: by the traditional method of map overlays of relevant attributes, and by a specially developed, automated Site-Selection Model (SSM). Five initial, Surrogate Sites, identified with the map-overlay approach, were then compared with the more rigorously produced scores from the SSM. The SSM, a process for optimization of site locations, accepts subjective, expert-based judgments and transforms them into a quantitative, reproducible, and documented product. The SSM is adaptable to any siting scenario. Forty-one factors relevant to the isolation scenario, including 21 weightable factors having a total of 123 scorable categories, have been entered into the SSM. Factors are grouped under project definition, unique environments, anthropogenic, geologic, biologic, weather, oceanographic and distance criteria. The factor scores are linked to a georeferenced database array of all factors, corresponding to 1°×1° latitude–longitude squares. The SSM includes a total of 2241 one-degree squares within 1000 n.m. of the U.S. coasts, including the western North Atlantic, the Gulf of Mexico, and the eastern North Pacific. Under a carefully weighted and scored scenario of isolation, the most favorable sites identified with the SSM are on the Hatteras and Nares Abyssal Plains in the Atlantic. High-scoring sites are also located in the Pacific abyssal hills province between the Murray and Molokai Fracture Zones. Acceptable 1° squares in the Gulf of Mexico are few and of lower quality, with the optimum location on the northern Sigsbee Abyssal Plain. Two of the five Surrogate Site locations, on the Hatteras and Sigsbee Abyssal Plains, correspond to the best SSM sites in each ocean area. Two Pacific and a second Atlantic Surrogate Site are located in low-scoring regions or excluded by the SSM. Site-selection results from the SSM, although robust, are an initial attempt to quantify the site-selection process. The SSM database exposes a significant lack of high-quality information for many areally mappable attributes on the abyssal seafloor, particularly bottom-current speed and measures of biologic productivity and flux. Terminologies and classifications of some measures, such as sediment types, suffer from parochialism and vary by ocean. Considerable research is needed even for a broad understanding of the environmental measures required to make sound societal decisions about use of the abyssal seafloor for disposal or other purposes.  相似文献   
4.
The controversial nature of urban congestion charging policies makes them politically risky. Urban planners, policy makers and politicians are forced to consider how they can legitimately introduce a policy that the public may not want. Implementation in London, and failure in Edinburgh, raise questions about whether they should seek full citizen support, or work strategically towards implementation in the face of public opposition.This paper reports on an investigation of the Stockholm congestion charging trial (SCCT). It analyses the strategy developed by the city authorities to create legitimacy for the implementation of the SCCT. The SCCT is examined in two steps, firstly how the ‘trial + referendum’ approach was successful in securing public acceptance, and secondly how key aspects of the design of the trial and the subsequent referendum were adjusted in response to emerging risks, demonstrating the pragmatic approach of the city leaders managing the policy process. The study suggests that the city leaders chose a clearly pragmatic approach, grounded in compromise, yet subtly designed to avoid openly confronting the status quo. The strategy was continuously adapted and adjusted, in the face of emerging risks, and clearly served to create consensus while avoiding difficult questions of urban mobility.  相似文献   
5.
Although considerable progress has recently been made in the evolution of marine traffic procedures in coastal and waterway areas, mariners are finding difficulty in coping with the diverse traffic schemes that have so far been devised. This paper is a plea for international and logical marine traffic management, so that ships can operate safely and efficiently within a framework of the proliferating offshore zonal legislation that we are now witnessing.  相似文献   
6.
This paper describes the development of a computer model and algorithms for finding the time-dependent minimum path between two stations in a multi-route, multi-mode transit system running to fixed schedules. Selection of the minimum path can be based either on journey time or on weighted time. A worked example using a simple transit network is given to illustrate how the model works. The model has several applications in transport planning: it can be used for generating route schedule information to guide transit users, for assisting in route schedule coordination, and for analyzing transit system accessibility.  相似文献   
7.
Public transport managers and operators face increasingly difficult problems in providing adequate levels of service at reasonable social and financial costs. A greater demand exists for analytical techniques which allow them to evaluate changes in operational strategies before committing themselves to implementation in the field. This paper describes the development of a discrete event simulation model for the analysis of on-street transit routes. The structure of the model is described and details are provided of the types of events which are explicitly modelled in the TRAMS package. The input requirements are described, and the modular nature of the simulation model is highlighted. The various options for output format are described, including the use of a computer graphics real-time animation option. The range of output performance measures are then discussed, and some comments on areas of application conclude the paper.  相似文献   
8.
Data collected during the Continuous Plankton Recorder (CPR) survey has been used to validate a three-dimensional hydrodynamic ecosystem model simulation of the North-west European Shelf for the years 1988–89. The CPR time series is unique to the North Atlantic region as a validation tool. Data were extracted from the model to correspond with those collected by the CPR survey, and both the model and survey plankton data were standardised to allow the comparison of model biomass with survey counts. Simple linear regression and absolute error maps provide a qualitative evaluation of spatio-temporal model performance of simulated diatoms, flagellates, total phytoplankton and omnivorous mesozooplankton. Comparisons of z-scores indicate that the model reproduces the main pelagic seasonal features, and there is good correlation between magnitudes of these features with respect to standard deviations from a long-term mean. The model is replicating up to 62% of the mesozooplankton seasonality across the domain, with variable results for the phytoplankton. There are, however, differences in the timing of patterns in plankton seasonality. The validation exercise has highlighted that the spring diatom bloom in the model is too early, suggesting the need to reparameterise the response of phytoplankton to changing light levels in the model. Errors in the north and west of the domain imply that model turbulence and vertical density structure need to be improved to more accurately capture plankton dynamics.  相似文献   
9.
Although considerable progress has recently been made in the evolution of marine traffic procedures in coastal and waterway areas, mariners are finding difficulty in coping with the diverse traffic schemes that have so far been devised. This paper is a plea for international and logical marine traffic management, so that ships can operate safely and efficiently within a framework of the proliferating offshore zonal legislation that we are now witnessing.  相似文献   
10.
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