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801.
Canada's federal government is responsible for ports. Despite this, an integrated national ports system has not been established. The Canadian system includes: the Canada Ports Corporation; Harbour Commissions; and Transport Canada's Public Harbours. These are historic divisions. Following a failed 1970s attempt to place all ports within Transport Canada, in 1983 parliament opted for a Crown corporation model in establishing the Canada Ports Corporation for Canada's major ports. This paper addresses the question of whether, in today's increasingly competitive environment, a more integrated and businesslike national system of ports is required. Alternative systems range from centralization to regionalization and enhanced 'commercialization' of local ports to privatization. A suggested alternative for Canada includes incorporating all commercial ports within the Canada Ports Corporation, using a regional system for planning, and augmenting local autonomy of financially self-sufficient ports by making them crown corporations. Eventual privatization of the expanded Canada Port Corporation is also considered.  相似文献   
802.
803.
Estimates of the numbers of trips likely to be made by individuals and of the modes of transport that will be available to them for those trips are provided by the trip production model. The objective of the work described in this paper was to investigate the geographical stability of the trip production model by comparing the numbers of trips estimated by the model when using national rather than local data. The 1972/3 National Travel Survey was used as the national data. Household interview survey data from the transportation studies of Lincoln, Sheffield/Rotherham, South East Dorset and Bristol were the local data sources. Three home based trip purposes are modelled; 24 hour work, 24 hour shop, 24 hour other.The models calibrated from national and local data perform similarly provided both operate with local trip rates. The car ownership sub-model with national parameters produces similar forecasts to the models with local parameters. There are probably real differences in household trip rates for some trip purposes between urban areas.  相似文献   
804.
The significance of the effects of steering compliance and aerodynamic life on high speed automobile's steering response was investigated on two vehicles, a Ford Falcon XW (1969) station-wagon and a GM-Holden Kingswood HQ (1974) sedan. An aerofoil was mounted above the front bumper bar of the Ford Falcon to enable the simulation of vehicles with very degraded aerodynamic characteristics. Mathematical analysis showed the importance of the inclusion of steering compliance effects in determining stability factor, and hence the vehicle's high speed yaw rate sensitivity. Both experiments and theory showed that the actual high speed yaw rate response is not significantly less than that predicted from a low speed skid pad test, however, slight errors were found which are likely to be due to steering system nonlinearity and the effects of aerodynamic lift.  相似文献   
805.
Traveler attitudes and behavior have been shown to correlate in numerous previous studies. However, the correlation by itself leaves open the nature of the interrelationships between traveler attitudes and behavior. For example, attitudes could either cause or be caused by behavior. In fact, both options are concurrently possible. Structural equations are applied to a set of data gathered from Los Angeles central business district workers to ascertain the direction and nature of interrelationships between attitudes and behavior with respect to frequency of taking the bus to work. A mutual dependence between attitudes and behavior is demonstrated in the context of this dataset and behavioral choice situation; behavior and attitudes concurrently cause each other. In addition, it is found that two attitudinal components, perceptions of and affect toward a mode, function differently with respect to travel behavior.  相似文献   
806.
Injuries to natural resources from the release of hazardous substances into aquatic environments have led to hundreds of millions of dollars in compensatory damages awarded under the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) and other legislation. The institutional mechanisms for negotiating and carrying out the terms of CERCLA natural resource settlements are still in their infancy, and each case has a unique set of injuries, assigned damages, payout schedules, trustee council membership and operating procedures, and environmental conditions and constraints. One of the settlements that has made significant progress toward large‐scale habitat enhancement has occurred in Elliott Bay, a busy, seriously impacted urban harbor in Washington State. The Elliott Bay case is unique among natural resource injury settlements because of the active involvement of two local governments, the City of Seattle, and Metro, who were named as defendants in a lawsuit brought by the National Oceanic and Atmospheric Administration (NOAA) on behalf of the natural resource trustees of Elliott Bay. Both local governments have maintained, and continue to operate, outfalls that discharge into Elliott Bay, and both entities were subject to attempts to recover damages under CERCLA. Following the filing of the lawsuit over injuries to the natural resources of the estuary, alleged to have resulted from the operation of these outfalls, the parties involved negotiated a consent decree settlement. The Elliott Bay/Duwamish Restoration Program has established a process to redress some of the injuries that were attributed to the operation of these outfalls.  相似文献   
807.
This article presents an overview of the relationship between geography and coastal management. It explores the nature of geography as well as the geographical underpinnings of key notions within coastal management, in particular, “coast,” “conflict,” and “integration.” The article considers the integrated coastal management process and tracks the influence of geography on the development of the discipline's theory and practice, as well as its academic infrastructure. The article concludes that although geography both underpins and offers useful insights into coastal management, a challenge remains to explore in greater depth the benefits of applied geographical approaches to the management of coasts.  相似文献   
808.
Abstract

local wastewater management policies can be important tools for protecting marine water quality when coordinated with sound land use and environmental planning. that relationship is examined through a review of the point and nonpoint source pollution issues associated with centralized versus decentralized wastewater management approaches, sewerage extension and plant expansion effects, and sewerage management practices. we use information provided by 161 local jurisdictions in coastal regions of the southeastern united states and various secondary regions of the southeastern united states and various secondary sources. the article concludes with a discussion of policy implications and recommendations to improve the coordination of local sewerage extension/expansion practices and land use planning.  相似文献   
809.
Abstract

Section 312 of the Clean Waters Act was implemented in 1980 and requires all vessels including recreational boats already equipped with Marine Heads (toilets) to install one of three types of USCG approved Marine Sanitation Devices. These regulations govern all lakes and coastal waters extending to the end of the U.S. territorial sea and is intended to prevent untreated effluent from reaching the marine environment. As provisions of the Clean Water Act are exempt from provisions of the National Environmental Policy Act, no Environmental Impact Statement was written concerning the impacts to the marine environment and the cost to the boating public. The study based on a small survey conducted on Narragansett Bay during the summer of 1980 develops several empirical models to estimate the total costs of MSD conversions. These estimates assume that all recreational boats longer than 21 feet were to comply with Section 312 regulations. Biological Oxygen Demand generated waste by both the resident and visiting fleets have also been estimated and costs per lbs. of BOD equivalent made. Based on these estimates the quantity of waste prevented from entering the receiving waters equals that of a community with less than 700 people. The capital investments of on‐board treatment approximates 30 ¢/gallon, nearly 1000 times the cost of treating municipal waste.  相似文献   
810.

The choice behaviour of low cost travel (LCT) modes is very sensitive to travel distance. A line haul system designed on the basis of current planning practice of locating widely spaced stations to cater auto and bus feeder modes with the primary objective of gaining travel speed is hostile to non‐motorized and low cost feeder modes. With the revival of interest in promoting the use of walk'n ride and bike'n ride modes, there is a need to develop an appropriate tool to examine the effect of their specific characteristics in establishing the number and location of stations.

A generic normative behavioural hybrid model for locating the cost minimizing number and location of stations is developed for an LCT‐fed line haul system. The model considers the system with many to many two dimensional line haul demand density function in which the density varies in both x‐ and y‐directions. The feeder mode choice behaviour is incorporated in the model by integrating probability‐access/egress distance function with the objective function. Explicit functional relationships among the parameters of these feeder modes such as modal share as a function of access/egress distance with the parameters of line haul systems are developed. Dynamic programming is used to minimize the system cost. The generic model is shown to collapse into several simplified models capable of yielding approximate solutions for several well known special cases. It has been shown that location of stations is sensitive to the through load on board as well as users’ cost that defines the choice behaviour at large. Numerical examples are presented to demonstrate the applicability of the model.  相似文献   
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