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161.
ABSTRACT

A dynamic model for marginal cost pricing of port infrastructures links costs to system performance by combining a power-law function with time-dependent queueing analysis. Additionally, the model incorporates the marginal cost of capacity, including the effects of economies of scale. This allows the calculation of the marginal cost price under a dynamic framework. The model accounts for nonlinear behaviour of port demand, which is sensitive to price and service levels. The effects over time of cost and service levels on the port’s operational performance are quantified. The proposed model allows determining the optimal timing for capacity investment. The model is a starting point for the application of marginal cost pricing to ports. However, for practical application of such pricing method it is necessary to apply a system’s approach, as productivity and costs must be assessed at the terminal’s component level. This should allow the derivation of a marginal cost function at the terminal’s component level.  相似文献   
162.
On 19 October 1989, the International Maritime Organization adopted a joint uslliberian resolution meant to advance international cooperation in maritime casualty investigations. This resolution reflected an international determination to achieve greater cooperation between different states in investigative matters, in a manner consistent with international law. This paper examines how the IMO resolution addresses some of the inherent problems in such a multi-national industry. It also examines the question of whether us lawmakers may, or should, impose stricter controls and restrictions unilaterally on foreign-flag ships which call on us ports.  相似文献   
163.
Standardized and free-format questionnaires on the state of coastal management were fielded to coastal management practitioners during three workshops and a national feedback and recommendation workshop. The most commonly cited responses were identified for each of 13 political regions and overall trends were identified. Management frameworks frequently included research, community organizing, education, livelihood, resource enhancement, resource protection, regulation, and networking components. Gender issues, documentation, and infrastructure investment were rare. The most commonly perceived environmental problem was illegal/ destructive fishing and its associated overfishing and low fish catch. The most commonly cited socioeconomic problem was the inadequacy of law enforcement. The best monitored variables were usually those related to environmental management: status and change of habitats, resources, and degree of enforcement/patrolling activities. The most common nonregulatory enhancement, aside from environmental education (which is the most popular), was mangrove reforestation. In terms of regulations, the majority of the respondents have reportedly formulated an integrated coastal management plan. In practice, regulating destructive and illegal fishing practices and then the establishment of fish sanctuaries are the next most implemented. The most popular quality-of-life enhancement strategies focused on the improvement of sustainable fishing as a livelihood and on a variety of supplementary livelihoods. The most usual institutional intervention being implemented was the setting up of local community people's organizations. Major factors which may influence success or failure of coastal management and recommendations on research, community organizing and livelihood, legislation and policies, implementation and coordination, and networking are also summarized.  相似文献   
164.
This paper presents the joint optimization of signal setting parameters and dynamic user equilibrium (DUE) traffic assignment for the congested urban road network. The simulation-based approach is employed to obtain the DUE condition for the case of multiple-origin multiple-destination traffic flows. The dynamic traffic assignment simulation program (DTASP), developed in C language is used to assign the traffic dynamically on the road network, whereas method of successive averages (MSA) is modified and used to arrive at the DUE condition. The artificial intelligence technique of genetic algorithms (GAs) is applied to obtain the optimal signal setting parameters and path flow distribution factor for DUE condition. The methodology developed in such a way that joint optimization of signal setting parameters with DUE is obtained. The proposed method is applied to the real network data of Fort Area of Mumbai city comprising of 17 nodes and 56 unidirectional links with 72 Origin–Destination pairs, where all the 17 nodes are signalized intersections. The traffic flow condition for the optimized signal setting parameters is considerably improved compared to the existing signal settings. The results prove that the GA is an effective technique to solve the joint optimization problem for the real network data.  相似文献   
165.
The responsibility for managing coral reefs and other coastal resources was largely devolved to coastal municipalities and cities in the Philippines in 1991 with the passage of the Local Government Code. Devolution of powers and responsibilities to local government has paved the way for mainstreaming coastal resource management at the local level. However, the capacity to carry out this mandate has only recently begun to mature as municipalities and cities gain an increased awareness of the importance of coastal resources to communities and economic development. Approaches and strategies to increase local government capacity for coastal resource management are described based on the experiences of the Coastal Resource Management Project of the United States Agency for International Development. Qualitative and quantitative data are used to illustrate the possible impact of these capacity building efforts and to describe the current capacity of local government to undertake coastal resource management. After five years of project implementation, coastal municipalities have increased technical capacity, have allotted financial resources, and have achieved key performance benchmarks in the delivery of coastal resource management as a basic service.  相似文献   
166.
A cost-benefit analysis is conducted on the double-hull requirements for oil tankers in United States' waters contained in the U.S. Oil Pollution Act of 1990. The benefits of reduced spillage are compared with the increased construction and operations costs of double-hulled vessels. In the most probable scanario, the expected benefits are only 20% of the expected costs. Double-hulls do not even show a positive net present value with the most favorable assumptions. Even if double-hulls prevent all of the spillage that occurs due to collisions and groundings, and that the damage per gallon spilled is as extensive as in the ‘Exxon Valdez’ incident, the benefits are under half of the costs.  相似文献   
167.
This paper analyses the occupational future of the American merchant seaman. Reasons for the decline, foreign competition, technological change, effective manning and the feast or famine cycle are analysed. Strategies for the resurgence of the occupation are discussed.  相似文献   
168.
This article provides results on the net benefits generated from the natural resources in the Bohol Marine Triangle (BMT) in the Philippines. The BMT spans over 112,000 ha and its coastal ecosystems are rich in biodiversity and provide economic opportunities to the coastal communities. With a 10% discount rate, the accumulated total net benefits for the BMT resources over a 10-year period is US$11.54 million. Tourism and the municipal fisheries are the most important direct use values of the coastal and marine resources of the BMT accounting for 44% and 39% of the total net benefits. Annual revenues attributed to ecosystems were as follows: coral reefs, US$1.26 million; beach/intertidal area, US$1.12 million; marine waters, US$646,501; mangrove, US$239,561; and seagrass, US$105,990. The large market values indicate the dependence of the local community on the BMT coastal and marine resources. In the same way, non-market values show the important life-support functions of coastal and marine ecosystems. The net benefits reflect the magnitude of potential losses due to improper management of coastal and marine resources in the BMT. This valuation highlights the importance of the coastal services to the BMT economy and draws attention to the benefits the local stakeholders derive from BMT coastal resources. Policy measures can now take into account these values to justify a sufficient investment in coastal management efforts to sustain the flow of coastal services in the interest of current and future generations.  相似文献   
169.
Abstract

Although New Zealand has a population of 3 million and a coastline of about 10,000 miles there are already heavy pressures on some parts of it. Historically, subdivisions of less than 10 acres require the setting aside of a one‐chain esplanade reserve as part of a general reserve contribution. Some national and regional parks also include significant areas of coast. Recently the Lands and Survey Department has commenced a detailed study of the coastline. Another very recent development is the requirement of an Environmental Impact Report for all major government works. The Waitemata Harbour has been the subject of a detailed study and the reports are now beginning to appear. There has been a heavy demand for shallow bays and estuaries for sanitary land fill, as well as for dredge fill. The main pressure on the coast at present is for holiday cottage sites and some legislative changes may be necessary. In the future new marinas will probably be considered particularly in relation to the extent they provide for the general public rather than a selected few. Industry is only just beginning to make an impact upon the coast. New power stations, natural gas or thermonuclear, are likely to be located on the coastline and this would bring some environmental problems. Recently, it has been argued that to ensure wise use of the coastline there should be national, rather than local or regional, control by a specially appointed Coastal Commission.  相似文献   
170.
Abstract

This paper presents an analysis of the findings of a survey of a sample of Beaufort county, South Carolina, households which was conducted to ascertain preferences for environmental quality. These preferences were approximated from survey responses on willingness to pay for environmental amenities and the size of payments households would require to forfeit them. A scale was developed and used to rank these responses ordinally, and the matrices of scaled responses for each of eight household annual‐income classes were subjected to factor analyses.  相似文献   
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