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921.
There has been an assumption that because many large marine protected areas (LMPAs) are designated in areas with relatively few direct uses, they therefore have few stakeholders and negligible social outcomes. This article challenges this assumption with diverse examples of social outcomes that are distinctive in LMPAs. We define social outcomes as inclusive of both social change processes and social impacts, where “social” includes all perceptual or material human dimensions. We draw on five in-depth case studies to report social outcomes resulting from proposed or designated LMPAs in Bermuda, Rapa Nui (Easter Island), Kiribati, Palau, and the Commonwealth of the Northern Mariana Islands & Guam. We conclude: (1) social outcomes arise even in remote LMPAs; (2) LMPA efforts generate social outcomes at all stages of development; (3) LMPAs have the potential to produce outcomes at a higher level of social organization, which can change the scope and type of affected populations and, in some cases, the nature and stakes of the outcomes themselves; (4) the potential for LMPAs to impart distinctive social outcomes results from their unique geographies and/or intersection with high-level politics and policy processes; and (5) social outcomes of LMPAs may emerge in the form of social change processes and/or social impacts.  相似文献   
922.
In recent years, road vehicle automation has become an important and popular topic for research and development in both academic and industrial spheres. New developments have received extensive coverage in the popular press, and it may be said that the topic has captured the public imagination. Indeed, the topic has generated interest across a wide range of academic, industry and governmental communities, well beyond vehicle engineering; these include computer science, transportation, urban planning, legal, social science and psychology. While this follows a similar surge of interest – and subsequent hiatus – of Automated Highway Systems in the 1990s, the current level of interest is substantially greater, and current expectations are high. It is common to frame the new technologies under the banner of ‘self-driving cars’ – robotic systems potentially taking over the entire role of the human driver, a capability that does not fully exist at present. However, this single vision leads one to ignore the existing range of automated systems that are both feasible and useful. Recent developments are underpinned by substantial and long-term trends in ‘computerisation’ of the automobile, with developments in sensors, actuators and control technologies to spur the new developments in both industry and academia. In this paper, we review the evolution of the intelligent vehicle and the supporting technologies with a focus on the progress and key challenges for vehicle system dynamics. A number of relevant themes around driving automation are explored in this article, with special focus on those most relevant to the underlying vehicle system dynamics. One conclusion is that increased precision is needed in sensing and controlling vehicle motions, a trend that can mimic that of the aerospace industry, and similarly benefit from increased use of redundant by-wire actuators.  相似文献   
923.
We explore how marine ecosystem–based management (EBM) is translated from theory to practice at six sites with varying ecological and institutional contexts. Based on these case studies, we report on the goals, strategies, and outcomes of each project and what we can learn from these efforts to guide future implementation and assessment. In particular, we focus on how projects dealt with the challenges of working across geographic scales and diverse governance arrangements. While we hypothesized that EBM in the United States would be distinct from EBM in developing countries due to differences in social and political factors, we found that sites faced similar challenges. Variation among sites appeared to be more closely related to the preexisting management context and the scale at which the projects began rather than to clear differences between the United States and developing country contexts. EBM project implementers were able to overcome many of these challenges by focusing on a limited number of specific objectives, starting at a small scale, pursuing adaptive management, and monitoring a diverse set of indicators. These findings are directly relevant to current and future EBM efforts in these and other places.  相似文献   
924.
Shipping traffic poses a worldwide threat to many large whale species. Spatially explicit risk assessments are increasingly being used as a tool to minimize ship-strike risk. These assessments often use static representations of shipping patterns. We used Automatic Identification System data to quantify variability in cargo shipping traffic entering and exiting San Francisco Bay, which contains some of the busiest ports in the United States, at three temporal resolutions: (1) before and after implementation of the California Air Resources Board's Ocean-Going Vessels Fuel Rule, (2) among seasons, and (3) day versus night. We used the nonparametric Mood's Median test to compare median daily distance traveled because the data were not normally distributed and the variance was not homogeneous. Our analyses show that shipping traffic off San Francisco is dynamic at both interannual and daily temporal resolutions, but that traffic was fairly consistent among the seasons considered. Our analyses emphasize the importance of economic and regulatory drivers on interannual shipping traffic patterns. Shipping traffic is expected to continue to change off the U.S. West Coast and to increase globally. These changes in shipping traffic could have implications for the risk of ships striking whales and should be included in risk assessments.  相似文献   
925.
926.
In the present paper a vibrational differential equation governing on a rigid beam on viscoelastic foundation has been investigated. The nonlinear differential equation governing on this vibrating syst...  相似文献   
927.
928.
Abstract

Offshore hydrocarbon exploration has been undertaken on Canada's Atlantic continental shelf since 1964. It is only recently, however, that the Hibernia find off the coast of Newfoundland has raised the possibility of the eventual production of oil. This article reviews the history of offshore exploration, comments on the locational significance of the Hibernia field, and analyzes the implications of the Newfoundland government's policies for affecting the location of onshore support facilities. A critique of these policies is placed within the context of coastal zone management and planning.  相似文献   
929.
The Gulf of California hosts astounding biodiversity that supports numerous economic activities in the region. These activities, and emerging threats, are placing pressure on the region's ecosystems. Government and civil society are working to address threats through several conservation and management mechanisms. Nevertheless, the use and incorporation of scientific information—a key component for creating effective and durable management—is still deficient. This article presents the concept of science integration and discusses the findings of a study that assesses the regional landscape, existing institutional arrangements, and capacity for using science to inform policy and management decisions. It also explores the current use of science within fisheries policy and management and the capacity of the National Network of Information and Research of Fisheries and Aquaculture (RENIIPA) and the State Fisheries and Aquaculture Councils, two mechanisms in the region. Finally, it shares lessons learned and offers recommendations on how the region can strengthen science-based decision-making. Results indicate that while there are some actors in the Gulf of California producing relevant science, there is varying capacity of intermediary groups connecting producers with users of science, or mechanisms in place to ensure that science is being utilized in decision-making processes. Moreover, despite having a well-developed landscape of producers and intermediaries and mechanisms in place for fisheries management in the region, effective science integration is not occurring.  相似文献   
930.
Oysters have been harvested on the east coast of Australia for many thousands of years. Coastal Aboriginal communities used the extensive estuarine oyster resource and may have farmed oysters by establishing shell cultch beds in shallow areas of estuaries. The British colonization of Australia commenced in 1788 and oysters were initially used for food and production of lime. Concerns about unsustainable exploitation led to introduction of legislation that directed the oyster industry to aquaculture in 1884. Translocation of oyster stock for fattening, from New Zealand to Australian east coast estuaries, was encouraged. Here evidence is presented that this activity resulted in “mudworm disease” appearing in oyster farming estuaries on the Australian east coast between 1880 and 1900. The pandemic permanently destroyed natural sub-tidal oyster reefs and forced the oyster industry to adopt avoidance farming techniques including intertidal farming to cope with mudworm.  相似文献   
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