3,119 research outputs found

    Chesapeake Bay Land Subsidence and Sea Level Change : an evaluation of past and present trends and future outlook

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    Ten Chesapeake Bay water level stations presently have a combined total of 647 years of water level measurements with record lengths varying between 35 years (1975-2009) at the Chesapeake Bay Bridge Tunnel, VA, and 107 years (1903-2009) at Baltimore, MD. All ten stations, with the exception of Gloucester Point, VA, are active stations in the National Water Level Observation Network of water level stations maintained by the U.S. National Oceanic and Atmospheric Administration, Center for Operational Oceanographic Products and Services. New technologies such as sea surface range measurements from earth-orbiting satellites now provide a global assessment of absolute sea level (ASL) trends relative to the center of a reference ellipsoid rather than fixed points on the earth’s surface to which relative sea level (RSL) measurements refer. New methodologies have also been applied to derive spatial averages of ASL trends over large regions with greater accuracy. Notwithstanding these advances, there is still no substitute for an accurate time series of water level measurements obtained locally, preferably one spanning several decades, when assessing RSL trends that will affect a specific community or township in the coming decades. RSL trends will determine local inundation risk whether due to vertical land movement (emergence or subsidence) or the ASL trend found as the sum of RSL trend and land movement when both are measured positive upward. In Chesapeake Bay, RSL trends are consistently positive (rising) while land movement is negative (subsiding). By choosing a common time span for the ten bay stations evaluated in this report, we are able to compare differences in RSL rise rates with approximately the same degree of confidence at each station. Uncertainty has been reduced by extracting the decadal signal present at all ten stations before using linear regression to obtain new RSL rise rates with smaller than usual confidence intervals, permitting both temporal and spatial comparisons to be made

    Constructing habitus: promoting an international arts trend at the Singapore Arts Festival

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    The Singapore Arts Festival (SAF) is Singapore’s largest government-supported international arts festival. SAF presents the best in international and local arts, in an attempt, to develop what it perceives to be a lack of cultural knowledge of the Singaporean arts-going public. Using Pierre Bourdieu’s key concept of ‘habitus’ together with an analysis of the programming of the festival, this paper will highlight how the festival seeks to create a specific cultural taste in Singaporean art-goers through privileging and promoting works that are internationally marketable to European countries. The paper will conclude that this programming style occurs at the expense of Singaporean artists and hinders the development of the city’s state cultural and artistic development

    Ethnopolitics Across Central and Eastern Europe in a State of Flux: Time for Updating and Upgrading?

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    This chapter illustrates why and how the existing theoretical models in the study of ethnopolitics need to be updated in light of the latest developments and the increasing impact of new catalysts. These are, namely, anti-immigration and the rise of the populist and radical right across Central and Eastern Europe. This chapter hints that the more systematic cooperation between academic experts in nationalism and academic experts in the populist and radical right will enable: (a) the former to assess more accurately the degree to which new variables such as Euroscepticism and anti-immigrant trends can reshape ethnopolitics, both as a living reality and a field of study, across Central and Eastern Europe; (b) the latter to formulate new interpretative models about how (right-wing) populist and Eurosceptic actors embed their agendas inside the pre-existing political cultures of nationalism and particularistic identity and memory politics. This chapter introduces and outlines the ethnosymbolic approach as well as the triadic and quadratic configurations of ethnopolitics. Then, it proceeds into a more empirical assessment of the applicability of these theoretical approaches in a series of case studies during the 1990s, as well as the more recent emergence of new catalysts and the ensuing necessity to update and upgrade the existing theoretical models

    Claimed Co-ethnics and Kin-State Citizenship in Southeastern Europe

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    The paper introduces the often neglected concept of 'claimed co-ethnics' in the analysis of citizenship policies. It argues that this is an interstitial category that further complicates the triadic nexus between national minorities, nationalising states and kin-states. The 'claimed co-ethnics' are defined as people who are recognised by the citizenship (or ethnizenship) conferring state as belonging to its main ethnic group, although they themselves do not embrace that definition. In addition to bringing the issue of claimed co-ethnics into focus, the paper elucidates how citizenship policies can affect groups that challenge the exact fit between ethnicity and nation, showing how national governments through particular citizenship policies and categorisation practices engage in the construction of these groups. The paper shows that the triadic nexus framework, which has had a strong influence on citizenship and minorities scholarship, needs to be revised to include unidirectional relations between the elements of the triadic nexus. The paper is based on the comparison between the cases of ethnic Vlachs (in the context of Albania and Greece) and Bunjevci (in the context of Serbia and Croatia).European Commission - Seventh Framework Programme (FP7

    Application of advanced technologies to small, short-haul aircraft

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    The results of a preliminary design study which investigates the use of selected advanced technologies to achieve low cost design for small (50-passenger), short haul (50 to 1000 mile) transports are reported. The largest single item in the cost of manufacturing an airplane of this type is labor. A careful examination of advanced technology to airframe structure was performed since one of the most labor-intensive parts of the airplane is structures. Also, preliminary investigation of advanced aerodynamics flight controls, ride control and gust load alleviation systems, aircraft systems and turbo-prop propulsion systems was performed. The most beneficial advanced technology examined was bonded aluminum primary structure. The use of this structure in large wing panels and body sections resulted in a greatly reduced number of parts and fasteners and therefore, labor hours. The resultant cost of assembled airplane structure was reduced by 40% and the total airplane manufacturing cost by 16% - a major cost reduction. With further development, test verification and optimization appreciable weight saving is also achievable. Other advanced technology items which showed significant gains are as follows: (1) advanced turboprop-reduced block fuel by 15.30% depending on range; (2) configuration revisions (vee-tail)-empennage cost reduction of 25%; (3) leading-edge flap addition-weight reduction of 2500 pounds

    OVI Emission in the Halos of Edge-on Spiral Galaxies

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    We have used the Far Ultraviolet Spectroscopic Explorer to search for OVI 1031.926, 1037.617 A emission in the halos of the edge-on spiral galaxies NGC4631 and NGC891. In NGC4631, we detected OVI in emission toward a soft X-ray bubble above a region containing numerous Halpha arcs and filaments. The line-of-sight component of the motion of the OVI gas appears to match the underlying disk rotation. The observed OVI luminosities can account for 0.2-2% of the total energy input from supernovae (assuming a full OVI emitting halo) and yield mass flux cooling rates between 0.48 and 2.8 M_sun/yr depending on the model used in the derivations. Based on these findings, we believe it is likely that we are seeing cooling, galactic fountain gas. No emission was detected from the halo of NGC891, a galaxy in a direction with considerably high foreground Galactic extinction.Comment: accepted for publication in ApJ, 16 pages including 4 figure

    A multiscale analysis of gene flow for the New England cottontail, an imperiled habitat specialist in a fragmented landscape

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    Landscape features of anthropogenic or natural origin can influence organisms\u27 dispersal patterns and the connectivity of populations. Understanding these relationships is of broad interest in ecology and evolutionary biology and provides key insights for habitat conservation planning at the landscape scale. This knowledge is germane to restoration efforts for the New England cottontail (Sylvilagus transitionalis), an early successional habitat specialist of conservation concern. We evaluated local population structure and measures of genetic diversity of a geographically isolated population of cottontails in the northeastern United States. We also conducted a multiscale landscape genetic analysis, in which we assessed genetic discontinuities relative to the landscape and developed several resistance models to test hypotheses about landscape features that promote or inhibit cottontail dispersal within and across the local populations. Bayesian clustering identified four genetically distinct populations, with very little migration among them, and additional substructure within one of those populations. These populations had private alleles, low genetic diversity, critically low effective population sizes (3.2-36.7), and evidence of recent genetic bottlenecks. Major highways and a river were found to limit cottontail dispersal and to separate populations. The habitat along roadsides, railroad beds, and utility corridors, on the other hand, was found to facilitate cottontail movement among patches. The relative importance of dispersal barriers and facilitators on gene flow varied among populations in relation to landscape composition, demonstrating the complexity and context dependency of factors influencing gene flow and highlighting the importance of replication and scale in landscape genetic studies. Our findings provide information for the design of restoration landscapes for the New England cottontail and also highlight the dual influence of roads, as both barriers and facilitators of dispersal for an early successional habitat specialist in a fragmented landscape
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