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51.
Separation from partner and family has been found to be one of the most significant causes of stress for seafarers, with separation from the family one of the most important ‘stress’ factors influencing a decision to reduce planned sea service. Drawing on in-depth interviews with seafarers' partners in the UK, China and India, this paper focuses on the impact of seafaring on family life, with particular attention given to the effects of differing conditions of service and the range of company support available to seafarers and their partners. The paper concludes that the negative consequences of seafaring can be minimized by such policies as shorter trips, continuous employment (rather than employment by voyage) and opportunities for partners and families to sail. Whilst these measures may have financial costs, these can be off-set by improved retention of seafarers and the avoidance of stress-related illnesses. Indeed, at a time when there is a projected shortfall of well-trained seafarers, such steps may be sound company policy  相似文献   
52.
Coastal managers have sought to enhance the collaborative inputs of stakeholder groups into management activities. Nonetheless, established organizational approaches have led to primarily consultative forms of engagement and constrained citizen involvement in formative activities. In Olympia, Washington, managers overseeing the Deschutes Estuary Feasibility Study (DEFS) implemented an innovative cooperative research planning initiative that diverged from conventional consultative processes. Stakeholders, rather than government officials, identified the research priorities for the socioeconomic component of this restoration feasibility study. This design method altered the traditional roles and responsibilities of different organizational actors, and the involvement of citizen groups in these formative activities changed the relationship between governmental and nongovernmental actors. Using conceptual frameworks from organizational sociology, this study develops insights into the behavior of the organizations involved with the DEFS cooperative planning effort, demonstrating how engaging stakeholders in formative research planning activities may foster new types of collaboration among coastal management organizations.  相似文献   
53.
Driving of off-road vehicles (ORVs) on sandy beaches is common and widespread, but is not universally embraced due to putative environmental impacts on beach biota. For ORVs to impact the beach fauna, traffic areas must overlap with faunal habitat: a fundamental pre-requisite for impact assessments but as yet un-quantified for sandy beaches. Thus, this study quantified the spatial and temporal patterns of ORV traffic on five Australian beaches, and measured the degree to which the distribution of intertidal macro-invertebrates overlaps with traffic zones. Traffic volumes on beaches can be considerable (up to 500 vehicles per day). The position of beach traffic across the beach-face is principally governed by tides and driver behavior. Despite driver education campaigns to the contrary, a considerable fraction of vehicles (16–67%) traverses the soft, upper shore near the foredunes. The majority (65%) of burrowing invertebrate species of the intertidal zone is directly exposed to traffic, save for species inhabiting the swash zone. Because beach traffic presents a formidable management challenge, a fundamental first step in identifying whether ecological impacts are indeed likely, is to assess the potential for spatial and temporal conflict between human pressures (e.g., ORVs) and biological resources (e.g., beach fauna). Although this potential is certainly substantial for sandy shores used by ORVs, the actual ecological impacts on the intertidal fauna can only be predicted in situations where the responses (e.g., direct mortality, behavioral changes) of individual species to beach traffic are known.  相似文献   
54.
In this paper, a Field Programmable Gate Array (FPGA) was used to implement a real-time cylinder pressure analysis. The goal of the project was to improve the accuracy of calculated heat release and center of combustion calculations to enhance the precision of engine control functions. Compared to today’s real-time pressure analysis systems, several additional physical effects were taken into account for this objective. The wall heat transfer was calculated based on the approach published by Hohenberg. A chemical equilibrium with six substances was assumed for the mixture composition and a real-time calculation method was developed. Furthermore, a two-zone model was adapted and implemented for this realtime analysis. The validation of the results and the rating of the improvement in precision were based on GT-SUITE simulation results as an offline reference tool. Compared to state-of-the-art analysis systems, it was possible to reduce the average error of the center of combustion position from 1.6° to 0.5° crank angle (CA) by taking the investigated effects into account. Moreover, it was possible to significantly reduce the time required for the calculation from one complete combustion cycle to 0.2°CA at an engine speed of 3,000 rpm by using a continuous calculation method on the FPGA. This led to an additional improvement of the ability to control the engine, especially under highly dynamic operation conditions.  相似文献   
55.
这是一个严肃的命题。作为艺术界的"饱学之士",龚福尔现代艺术中心(Confort Moderne)将通过SarahBraman的雕塑传达一种"针对近期某些愤世嫉俗的知识分子言论以及带有自我反省色彩的玄妙语言而作出的救赎性反应"。我可以向你保证,有许多理由足以促使你去普瓦捷(Poitiers)参观这位美国艺术家的展览!首先,你可以看到各种  相似文献   
56.
This study explores the growth of electronic home shopping in terms of likely transportation and communication interactions. Although opportunities exist to shop from home today, most consumers initiate travel trips to stores or markets. Widespread use of automobiles has facilitated the retailing configurations we know today but the development of new electronic networks could change this. This study establishes a baseline to explore shopping activities using two‐day travel activity data from a large U.S. metropolitan area. It is found that people who telework from home today spend more time engaged in shopping activities than other workers. Potentially, their saved work travel is converted into new trips. In the future, saved shopping travel might be converted into other types of travel, and modelling results show that for busy working women, there is a latent demand for maintenance‐related activities. The study results suggest that electronic home shopping will bring into play complex interactions between communications and transportation.  相似文献   
57.
Domestic management of historic shipwrecks and other Underwater Cultural Heritage (UCH) resources located in the United States coastal zone is extensively fragmented and a portion of it has significant implications in terms of international law. In the United States coastal zone, UCH (largely historic shipwrecks) falls under one of three general regimes, depending on where the resource is located and subject to specific and individual requirements: the General Maritime Law, the Abandoned Shipwreck Act, and the Marine Protection, Research and Sanctuaries Act, also known as the Marine Sanctuaries Act. After examining the development of and current status of these regimes, this article will suggest policies for a stronger, more coordinated federal management regime in United States coastal waters. It will specifically argue that a recent decision by the United States Court of Appeals for the Fourth Circuit provides a well-designed paradigm that could be linked with pertinent aspects of the three identified regimes to create a unified coastal governance mechanism for sunken historic shipwrecks.  相似文献   
58.
The Ohio Department of Natural Resources and the U.S. Office of Coastal Zone Management have proposed the Old Woman Creek estuary on Lake Erie as the nation's first freshwater estuarine sanctuary. Designation as an estuarine sanctuary will preserve 637 acres of marshland, sand bar, a barrier beach, and surrounding forested uplands for public education and research. The original January 1975 grant application required modification following local residents’ objections to purchases of highly productive farmland and land‐use controls on a watershed‐wide buffer zone. A federal grant award was made in July 1977, with full acquisition anticipated by the end of 1978.  相似文献   
59.
Some organisms that live just below the sea surface (the neuston) are known more as a matter of curiosity than as critical players in biogeochemical cycles. The hypothesis of this work is that their existence implies that they receive some food from an upward flux of organic matter. The behaviour of these organisms and of the associated organic matter, hereafter mentioned as floating biogenic material (FBM) is explored using a global physical–biogeochemical coupled model, in which its generation is fixed to 1% of primary production, and decay rate is of the order of 1 month. The model shows that the distribution of FBM should depart rapidly from that of primary production, and be more sensitive to circulation patterns than to the distribution of primary production. It is trapped in convergence areas, where it reaches concentrations larger by a factor 10 than in divergences, thus enhancing and inverting the contrast between high and low primary productivity areas. Attention is called on the need to better understand the biogeochemical processes in the first meter of the ocean, as they may impact the distribution of food for fishes, as well as the conditions for air–sea exchange and for the interpretation of sea color.  相似文献   
60.
A fully-coupled biological–physical–chemical model of a coastal ecosystem was constructed to examine the impact of suspended mussel culture on phytoplankton biomass in Tracadie Bay, Prince Edward Island, Canada. Due to the extent of mussel culture there, we hypothesised that shellfish filtration would control the concentration and distribution of phytoplankton and other suspended particles in the bay. Circulation was delineated with a tidally-driven 2D numerical model and used to drive an ecosystem model with a focus on pelagic components including phytoplankton production, nutrients, detritus, and mussels. The benthos were treated as a sink. Nutrients and seston were forced by tidal exchange and river input, with phytoplankton additionally forced by light. Boundary conditions of seston and nutrients were derived from field studies with an emphasis on the contrast between spring (high river nutrients, low temperature) and summer (low river inputs and high temperatures). Model output was used to map phytoplankton carbon over the bay for each season and in the presence of mussels and river nutrient input. Results indicate severe depletion effects of mussel culture on overall phytoplankton biomass, but no spatial pattern that can be attributed to grazing alone. Primary production generated by nutrient-rich river water created a mid-bay spike in phytoplankton that dominated the spatial pattern of chlorophyll-based carbon. Model results were validated with surveys from a towed sensor array (Acrobat) that confirmed the river influence and indicated bay-wide depletion of 29% between high and low water. Our model results indicate that the farm-scale depletion emphasised in previous studies cannot simply be extrapolated to seston limitation at the ecosystem level.  相似文献   
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