Full scale ice sea trials of Korean ice breaking research vessel ‘Araon’ on the big floes near Antarctica

A speed sea trial was performed in the Amundsen Sea in February and March of 2012. The Korean ice breaking research vessel “Araon” was used to check speed performance on the big floes. Two of ice trial cases were carried out. We describe the time history of location, the engine power, and the revolutions per minute during the ice trial, and the trajectory of the ship. Additionally, the measured ice properties are considered and discussed. The ice trial results were analyzed according to variation in ice thicknesses, ice strength, propulsion power, and the speed level of the ship. Our analysis results are compared to model test results and ice trial results. A correction to the target ice thickness was used to compare the power and speed relation in the same ice thickness because it is easy to know the relative speed performance of the ship. The Hamburgische Schiffbau-Versuchs Anstalt method was applied for the correction. The speed of Araon in big floes was higher than the speed in level ice. The speed after the correction at 10 MW of power and 103 cm of ice thickness was 5.4 knots based on analysis results.     

Determinants of motor vehicle crash fatalities using Bayesian model selection methods

Motor vehicle crashes continue to result in large numbers of fatalities each year and represent the leading cause of death for young persons. In 2006, for example, there were over 42,700 fatalities associated with these crashes. Understanding the causes of these crashes and methods to reduce them continues to be of great interest to economists, public health officials, and policy makers. We present in this paper statistical models using a rich set of panel data covering the period 1980 to 2007 by state and the District of Columbia. Our choice of variables is based on an extensive literature highlighting the importance of policy, safety, demographic, and economic determinants of fatality rates.     

Understanding Recreational Boater Attitudes to Zoning in a Proposed Marine Protected Area

Although the success of marine protected areas (MPAs) and associated zoning schemes is largely dependent on stakeholder acceptance and support, there have been relatively few studies examining the response of recreational stakeholders to MPA proposals. This study investigates the response of recreational boaters to a proposed MPA in British Columbia, Canada. Using a structured questionnaire (n = 543) and a focus group (n = 6), the research examines the level of support for the concept of marine zoning and identifies key factors influencing support or opposition. Results indicate that a small majority of recreational boaters support the concept of marine zoning, but that there are areas of concern that ought to be addressed as MPA implementation proceeds. Support for zoning was strongly related to perceived benefits, particularly environmental benefits. Furthermore, perceived benefits overall were found to outweigh concerns as determinants of recreational boater support for zoning. Major dimensions of opposition included perceptions of over-regulation, loss of access for boating, and mistrust of the government. A suggestion is that such concerns may be mitigated through focused communication and meaningful involvement of boaters in the zoning process.     

Geographical variations in hurricane risk and legislative response

Abstract

Risk from the “natural event system”; of hurricanes varies greatly along the U.S. coastline, and so do the property and lives at risk. Damage potential from storm surge in the Miami area is less than a third that of the Tampa area. However, damage potential from winds in the Boston and New York areas exceeds that of either the Miami or Tampa areas. Passage of time since the great hurricane disasters near the turn of the century and improvements in the warning system may make coastal dwellers underestimate the likelihood of a hurricane catastrophe. But population growth near the coast has been more than three times the national average, and 10 of 58 coastal segments 50 miles in width more than doubled in population between 1960 and 1970. Twenty‐two segments increased by more than 25,000 people with six increasing by 150,000. Legislative response to the growing hazard has varied as widely as risk but is not clearly correlated with risk.     

Evaluating the impact of PSC inspectors’ professional profile: a case study of the Spanish Maritime Administration

Full-scale globalisation of trade has been accompanied by a progressive liberalisation of maritime transport. The proliferation of open registries has created a situation in which Port State Control (PSC) has become much more effective than the feeble or non-existent control exercised by those States. This study has been conducted on the influence of the professional profile of inspectors on inspection results. The objective of our paper was to evaluate the impact of PSC inspectors’ professional profile by conducting a case study of the Spanish Maritime Administration. The paper concludes with a discussion of the correlation between deficiencies detected and professional profiles.     

Coastal land management in New Zealand

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.     

Development of Green-Naghdi models with a wave-absorbing beach for nonlinear, irregular wave propagation

Two-dimensional and three-dimensional Green-Naghdi (GN) models equipped with a numerical wave-absorbing beach have been developed to simulate nonlinear, regular, and irregular wave propagation. The numerical beach is introduced near the downstream boundary to absorb outgoing waves. An appropriate amount of numerical damping and an appropriate length of numerical beach are investigated using numerical experiments. The results show that the GN models with a numerical beach work very well in simulating wave propagation in water in a small computational domain.     

On the axial force induced on a duct by a propulsor

The axial force induced on a duct (duct thrust) which surrounds a propulsor is, by means of an energy conservation argument, expressed in terms of the thrust and power of the propulsor and the kinetic energy losses per unit of time of the propulsor and the duct. Emphasis is put on the linear theory of an axisymmetric ducted actuator disk, where it is shown that the work done by the duct thrust is equal to the extra work done by the actuator disk when it is surrounded by the duct. This simplified model gives more insight into the interaction between the propeller and the duct and on the limits of linearization.     

Pb and Pu in the Northeast Water Polynya, Greenland: particle dynamics and sediment mixing rates

Distributions of the radionuclides ²¹⁰Pb and ^239,240Pu in sediment cores from the Northeast Water Polynya, Greenland, showed that these nuclides reached depths of 5–15 cm by particle mixing and sediment accumulation. End-member average values of the particle mixing coefficient and sediment accumulation rate were 0.13 cm² y⁻¹ and 0.06 cm y⁻¹, obtained from the ²¹⁰Pb profiles by assuming that each process is dominant relative to the other. Both ²¹⁰Pb and ^239,240Pu were measured on four cores; using the Pu data to constrain mixing rates produced corrected sediment accumulation rates that were 20–80% of the values calculated by neglecting mixing. Organic carbon burial in the polynya sediments was ≤0.4 mmol m⁻² d⁻¹, based on measured POC values at depth in the sediments and sediment accumulation rates corrected for mixing. This value is about 1% of the independently measured POC flux leaving the euphotic zone and compares with benthic carbon remineralization rates of 7% calculated by others from O₂ uptake in the sediments.The inventories of excess ²¹⁰Pb in the sediments ranged from 6 to 28 dpm cm⁻². Relative to the atmospheric input of ²¹⁰Pb and in situ production from decay of ²²⁶Ra, approximately 5 dpm cm⁻² of ²¹⁰Pb was being removed from the water column. The difference between the removal from the water column and sediment inventories suggests a net import of ²¹⁰Pb to the polynya. This may occur by input of dissolved ²¹⁰Pb from offshore waters or by input of ²¹⁰Pb carried by sea ice. Particulate matter in land-derived fast ice adjacent to the polynya contained 330 ± 14 dpm of excess ²¹⁰Pb g⁻¹. If particles transported in sea ice are comparable to those extracted from fast ice, then sea ice transport into the polynya followed by melting may be an important source of excess ²¹⁰Pb to the area. Fast ice also may contribute ²¹⁰Pb if portions break off and melt within the polynya, as occurred in 1993.