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During 2015, the NOAA Office of National Marine Sanctuaries led a systematic seabed mapping survey along the Arctic coast of Alaska in search of whaling ships abandoned in 1871. The purpose of the expedition was to determine if wreckage from these abandoned ships was still present in the survey area, and, if so, to assess and document its location, status and condition. The project mapped approximately 50 km2 of seabed using sidescan sonar and magnetometry and identified six sites that contained wreckage from at least two whaling ships. Magnetometry data also suggested that additional wreckage may be buried in the seabed.  相似文献   
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The Boeing Company, collaborating with NOAA to address innovative ways to make ocean observations, provided their autonomous underwater vehicle, Echo Ranger, to conduct the first deep-water archaeological survey of the scuttled aircraft carrier USS Independence in the waters of Monterey Bay National Marine Sanctuary in March 2015. While a preliminary effort, and not comprehensive, the survey confirmed that a sonar feature (previously not proven to be an archaeological feature) charted at the location was Independence, and provided details on the condition of the wreck. At the same time, new information from declassified government reports provided more detail on Independence’s use as a naval test craft for radiological decontamination as well as its use as a repository for radioactive materials at the time of its scuttling in 1951. The wreck is historically significant, but also of archaeological significance as an artifact of the early years of the atomic age and of the Cold War. This article summarizes Independence’s contexts, its nuclear history, and the results of the survey of the wreck site.  相似文献   
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Energy issues are becoming increasingly common subjects of instruction in undergraduate- and graduate-level classrooms across a variety of disciplines. The interdisciplinary character of energy studies provides geographers with a great opportunity to present different applied and theoretical approaches to help students conceptualize energy issues from a critical perspective. This article presents a class intervention as an example of how to incorporate geographic concepts and political economic theory into the classroom to help students understand the social, political, economic, and environmental implications of energy production, distribution, and consumption at multiple scales from a critical perspective.  相似文献   
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Performance-based earthquake engineering methodologies often require a probabilistic model of structural demand. Since observations masking the probability distribution of the majority of the data are frequently found, robust estimation methods are proposed to estimate the probabilistic model parameters (i.e., central value and dispersion). The performance of thirty-three robust dispersion estimators is evaluated, for different sample sizes, using the chord rotation, curvature, shear force, and inter-story drift demands obtained after analyzing five reinforced concrete structures under real earthquake records scaled to several intensities. Based on the results, combinations involving dispersion and central value (defined in a companion article) estimators are proposed.  相似文献   
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ABSTRACT

Mainstream ecological thought is explored in three sections: (i) Epistemological traits. Given the typical scientific development and the necessity of preserving our intellectual heritage, the conservatism outlined in (i) is cyclical, so its stages are graphically summarized. (ii) Methodological benchmarks antithetically derived from (i), in order to get faster advancement consistent with the growing environmental challenges which spur ecological development. (iii) The renaissance of an old paradigm. This section exposes the misunderstanding of the physical concept of equilibrium by the mainstream ecological thought; this explains its current state. Consequently, section (iii) also summarizes the evolution of a recent set of proposals (organic biophysics of ecosystems) that rescues the foundational paradigm of ecosystem ecology based on physics, neglected by the mainstream thought before producing its most valuable results. We highlight that the main problems emerge from the weakness of integration between ecology, physics and epistemology, and spurious links between ecology and neoclassical economics.  相似文献   
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This article is the first of two companion articles addressing the statistical characterization of seismic demand. Performance-based earthquake engineering methodologies often require the characterization of central value estimates of structural demand. Since outliers can occur in the data, central value estimates should be determined by robust estimation methods. The performance of 50 robust central value estimators is evaluated, for different sample sizes, using the chord rotation, curvature, shear force, and inter-story drift demands obtained after analyzing five reinforced concrete structures under real earthquake records scaled to several intensities. Based on the results, seven estimators are proposed for different sample sizes.  相似文献   
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During the period 2014–2020 it will be the first time since Spain joined the European Economic Community that the Southern region of Andalusia will not be considered as one of the Objective 1 priority areas for the European Regional Policy. This paper analyses the economic impact of the foreseeable withdrawal of an important amount of European Structural Funds in the region. Our point is to develop a dynamic general equilibrium model to assess, under different simulation scenarios, the effects of the removal of this funding on the main regional economic indicators, specially focusing on GDP growth, a key variable for the future of the region.  相似文献   
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A wrecked submarine lying in the inter-tidal zone of Isla San Telmo, off Panama's coast, has been identified as Sub Marine Explorer , a rare surviving example of a mid-19th-century submersible. One of the world's first successful lock-out dive-chambers, the craft had a fatal design aspect that ultimately harmed its crew and may have killed the builder through the effects of pressure. Documentation of the submarine provides a detailed understanding of this technologically advanced but flawed craft.
© 2006 The Author  相似文献   
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