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1.
The aim of this paper is to investigate the behaviour of water transportation company stock returns in the U.S. stock exchanges from 1985 to 1994 in order to determine whether the systematic risk of this industry is different from that of the 'average' company in the market, whether it has changed over the ten year period, over bull and bear market conditions, and whether there is a firm 'size' effect in the industry. In the context of the Capital Asset Pricing Model (Capm), we find that the systematic risk of the shipping industry return is not different from that of the 'average' company. It is also found that the covariance of water transportation companies with respect to the overall stock market return did not change over the ten year period although it appears that it has changed over normal upward/downward market movements. There is also reasonable evidence that the intercept of the equation might have changed over normal upward/downward market movements. Finally, we document contradictory evidence regarding the size effect; during the period 1985-1989 we find small companies to have significantly higher returns and risk while during the period 1990-1994 medium size companies tend to have higher risk than small and large firms, which is not however compensated by higher returns.  相似文献   
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This paper examines the dynamic behaviour of second-hand prices of tankers and dry-cargo vessels over various time periods, with a view to determining whether or not the markets for such assets are efficient. It extends and re-analyses the results of an earlier study by Hale and Vanags, published in this journal in 1992. Using a more modern method of testing for cointegration, it is shown that both the tanker and dry cargo markets appear to be cointegrated, a fact which would suggest that these markets are inefficient. It is suggested that the existence of cointegration does not necessarily imply market inefficiency, if the factors that create the common trends are themselves stochastic in nature. With this in mind, it is argued that the evidence put forward in this paper is still consistent with market efficiency in the long run.  相似文献   
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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   
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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   
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Abstract

Growth in the number of cottager, or lake property owner, associations in Ontario has been rapid. Cottager associations attempt to address directly, and influence government decision‐making on, issues affecting shoreline management and the recreational experience of cottagers. However, associations infrequently resolve these issues to their satisfaction. A questionnaire and case study show that the nature of the issue, human and financial resources available to the association, and the nature of the decision‐making process affect the extent to which associations influence outcomes. Unreceptiveness of government officials to association participation in decision‐making and confused agency jurisdictions over shoreline resources appear to inhibit association effectiveness. Concerns about the status of shoreline management in Ontario and public participation in decision‐making are raised.  相似文献   
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Abstract

Seaport expansion often generates tensions between the national interest in efficient transport and local interests in water quality and habitat preservation. The governing American permitting system, however, establishes an extraordinarily cumbersome, legalistic, and costly method for balancing environmental and economic considerations. A case study of the Port of Oakland illustrates the tendency. For four years, plans to find an environmentally acceptable site for dredged material have been stymied by a sequence of inconclusive regulatory and judicial proceedings. Meanwhile, large container ships can enter and leave Oakland harbor only at high tide, and not fully loaded. Despite the absence of any authoritative determination concerning environmental risks, the port was compelled to accede to progressively more expensive disposal methods. Such “adversarial legalism”; is not unique to the Oakland harbor case, but recurs in other policy spheres. It stems from a governmental structure that fragments decision‐making power among many agencies, that constrains regulatory discretion with legal demands for scientific certainty, and that by allowing agency decisions to be challenged readily in court, encourages legalistic defensiveness and extortion rather than compromise. The article concludes with a discussion of the conditions under which regional planning bodies might overcome these centrifugal tendencies.  相似文献   
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The increasing number of electronic control units (ECUs) inside a vehicle implies the need to develop and deploy on board robust, low latency and low complex telecommunication systems. In this respect, power line communications (PLC) is an attractive solution. The benefits provided by the introduction of power line communications in the in-car environment are multiple and they are related to the possibility of exploiting the existing and capillary wiring infrastructure to simplify the design of the in-vehicle data network (IVN) and, more importantly, to save weight and cost of the wiring harness. In this paper, we deal with the analysis of the performance achievable by applying innovative advanced modulation techniques to in-car measured power line channels, i.e., multicarrier (MC) and impulsive ultra wideband (I-UWB) modulation. We show that for low speed command and control applications, I-UWB is suitable since it requires lower power and lower computational efforts w.r.t. MC systems. Furthermore, we study the design of the optimal transmitted pulse to further improve the performance of I-UWB.  相似文献   
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The development of a parametric hull form design system utilizing combined knowledge-based and objectoriented methodologies, approaches, and techniques is the major purpose of this research. One objective was the development of a powerful, intuitive, and parameter-based hull definition system with a related hull definition advisory system that would provide useful and necessary advice to the user. Object and knowledge modeling activities were conducted during the analysis and design stage to facilitate the implementation of a hull design program and advisory system. The hull design system includes the generation of a geometric model from a process of aggregating simple user-selected shapes representing different boundaries. Design involves the capability to vary simple parameters such as entrance angles, length-breadth ratios, and radii to define local and general surface geometries. Hydrostatic calculations are included for analysis; results are referred to an advisory system for evaluation and the determination of the acceptability of parameters and analysis results. The advisory system includes a knowledge bases consisting of hull form databases, results of the statistical analysis of data, design parameter constraints, and expert knowledge acquired from designers, reference materials, and technical reports. Use of the design tool with the advisory system results in the rapid generation of hull forms and associated design evaluations. Flexibility in decision making results from the separation of the design system from the advisory system. The independence of the two systems allows for a wide range of user experience with experts using the design tool with minimal reference to the advisory system. On the other hand, the expertise and knowledge stored in the advisory system is fully available to inexperienced designers and users.  相似文献   
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