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871.
Jan A. Berg-Andereassen 《Maritime Policy and Management》2013,40(4):381-395
This paper tests two fundamental hypotheses concerning international maritime statistics. The first one deals with the question of stationary of the maritime market statistics. The second hypothesis tested is the assumption that the international maritime statistical time series are not distributed according to a normal of Guassian probability law, but rather belong to the same family of distributions with distinctly different critical parameters. Through well documented statistical methods, the paper concludes that the international freight rates observed on a day to day basis are generated by a random walk process. The paper finds that the shipping industry's conventioal wisdom is essentially correct. ‘Last done’ is as good a forecast of tomorrow's freight rate as any other generated by more sophisticated forecasting methods. Furthermore, freight rates and secondhand tonnage prices fluctuate closely together. The freight rates are generated by stochastic processes fully described by the Paretian family of distributions. The critical parameters of these distribution, the characteristic exponents, are such that the risk conscious ship operator can indeed reduce his exposure to risk by securing a correct set of freight rate contracts. 相似文献
872.
Travel time variability (i.e., random variations in travel time) leads to a travel time distribution for a repeated trip from a fixed origin to destination (e.g., from home to work). To represent travel time variability, a series of possible travel times per alternative (departure time, route or mode) are often used in stated choice experiments. In the traditional models, the probabilities associated with different travel scenarios (e.g., arriving early, on time and late) shown in the experiments are directly used as weights. However, evidence from psychology suggests that the shown probabilities may be transformed (underweighted or overweighted) by respondents. To account for this transformation of probabilities, this study incorporates perceptual conditioning through a non-linear probability weighting function into a utility maximisation framework, within which the empirical estimate of the value of expected travel time savings is estimated. The key advantage of this framework is that the estimated willingness to pay value can be directly linked to the source of utility (i.e., the probability distribution of travel time), while taking into account the perceptual transformation of probabilities. 相似文献
873.
Lynne Zeitlin Hale Mark Amaral Abdulrahman S. Issa B. A. J. Mwandotto 《Coastal management》2013,41(1):75-85
Site-based projects were initiated in Chawka Bay-Paje, Zanzibar, and Nyali-Bamburi-Shanzu, Kenya, to demonstrate the benefits of an integrated coastal management (ICM) approach for addressing coastal issues such as tourism development and enhancement of resource-dependent village economies in eastern Africa. A two-year, multidonor project used three primary strategies to make rapid, but sustainable, progress toward ICM. These included using interagency government teams for ICM planning, adopting an internationally recognized framework for ICM as a project ''road map,'' and explicitly incorporating capacity-building strategies into all aspects of the project. Within two years, integrated ICM action strategies, prepared through participatory processes, were being implemented at both sites, and both teams were working to expand the scale and scope of ICM in their nation. More importantly, the project helped create committed, capable, interagency groups that continue to work together to address urgent ICM issues. 相似文献
874.
Iván Cáceres Rabionet Vicente Gracia García Montserrat Rubio Galindo 《Coastal management》2013,41(3):254-273
Artificial islands have been constructed next to large cities due to the need for extra space in highly populated areas. These emerged structures have been used by many countries as platforms for developing infrastructure (airports, harbors, highways, etc.), rebuilding ecological areas, and creating new spaces for tourism or residential areas. In this study, two state-of-the-art numerical models for wave propagation and nearshore circulation are used to simulate the effects of an emerged artificial island on the Barcelona coast. Several sea indicators (wave height, intensity and direction of currents, and mean water level) are analyzed to assess the changes likely to be induced by an artificial island. Three different situations are studied and the indicators are compared across the different tests to obtain information that can be used in the planning process of these structures. In two-meter wave conditions, the tests show that wave height is generally reduced in the sheltered area, which leads to improved safety for beach users (bathing is prohibited when wave height exceeds the two-meter threshold). However, the numerical models also reveal that velocities in the sheltered area usually decrease, which must be controlled to prevent stagnation in the bathing area. 相似文献
875.
E. G. Coombes A. P. Jones I. J. Bateman J. A. Tratalos J. A. Gill D. A. Showler 《Coastal management》2013,41(1):94-115
As tourists are sensitive to weather conditions and changes to the environments they visit, it is likely that climate change will affect coastal recreation in the future. To understand these impacts, it is first important to quantify how visitor numbers are associated with beach characteristics and weather patterns. Using the East Anglian coastline, UK, as a case study, information on the spatial distribution of visitors recorded from aircraft flights is combined with beach characteristic data in a Geographical Information System. In addition, surveys are undertaken at two beaches to assess temporal variations in visitation. The study finds a diverse range of characteristics are associated with visitor numbers. These findings are evaluated alongside the anticipated effects of climate change and management policies. Although it is predicted that warmer weather will increase visitor numbers overall, sea-level rise may reduce numbers at wide sandy beaches, which are currently most preferred by tourists. 相似文献
876.
Abstract The Sefton Coast Management Scheme in northwest England uses an area‐based project to achieve coordinated land management. It is founded on the ‘'Heritage Coast'’ model pioneered by the Countryside Commission where a ‘"Project Officer”; is employed to promote the Scheme and translate the aims into practical achievement. The Sefton Coast is described and a summary of British coastal planning policy precedes a detailed analysis of the Scheme. The Scheme is assessed with reference to practical management work, its success in competition for scarce financial resources, and the involvement of volunteers. It is established that the Project Officer is crucial to the success of the Scheme and that area‐based management can best be achieved through the local government planning process. Coastal planning needs now to be reviewed at national level to develop a policy for the whole coast using the experience of projects such as the Sefton Coast Management Scheme. 相似文献
877.
Chris A. Wold 《Coastal management》2013,41(2):213-230
Abstract This article explores the lack of uniform penalty assessment in the National Oceanic and Atmospheric Administration's (NOAA) civil penalty policy under the Fishery Conservation and Management Act (the Magnuson Act). The author sugests that NOAA's inconsistent penalty assessment invites noncompliance by fishers because they view the penalties as unfair and arbitrary. In particular, deterrence is undermined by the absence of a provision that removes the economic benefits of noncompliance. NOAA's policy is contrasted with the Environmental Protection Agency's (EPA) civil penalty policy, which uniformly assesses penalties while tailoring the penalty to the individual facts of the case and effectively removing the economic incentives of noncompliance. If NOAA implemented a policy similar to EPA's, NOAA would secure increased Magnuson Act compliance and higher penalty amounts. 相似文献
878.
J.-D. Caprace C. Petcu M. G. Velarde P. Rigo 《Journal of Marine Science and Technology》2013,18(3):404-417
In this article we describe the development of a tool that allows planners to efficiently and effectively plan space within valuable areas of a shipyard. Traditionally, space is considered as resource; however, it is difficult to accurately account for and plan its consumption with the currently available planning software’s. The spatial scheduling tool described in this article can be used by planners to manually or automatically reserve space within the shipyard for construction of large blocks over the entire erection period of the ship. The software is coupled with a heuristic optimization solver inspired by an algorithm used for "3D bin-packing problems." The result is the ability to efficiently generate and compare multiple space allocation alternatives in a reduced time with the ultimate goal of maintaining the critical ship erection schedule. A better solution than manual or semi-automatic allocation of blocks can be obtained through the optimization module. 相似文献
879.
César Ducruet 《Maritime Policy and Management》2013,40(4):377-394
While the geographical and economic factors concerning the development of hub ports are widely described by a variety of scholars and professionals, there is no recognized methodology measuring the hub dependence of a given port, region, or country. Based on a 20-year database of vessel movements, this paper proposes a methodology measuring hub dependence. North Korea offers a good case of a constrained economy facing dramatic internal and external pressures. Notably, the weight and geographical extent of its maritime connections are worth analysing because of its contrasted evolution from Soviet influence, geopolitical isolation, and growing trade due to economic reforms and increased foreign investments. The main results of this study show the spatial shift from long-distance calls to feeder calls: global foreland contraction, regionalization within Northeast Asia, and traffic concentration upon closest hubs of which South Korean ports. We conclude that hub dependence is a combination of local constraints and trade growth. The political implications of this phenomenon are explored, and a spatial model of hub dependence is proposed. 相似文献
880.