61 research outputs found

    The structural role of the core literature in history

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    The intellectual landscapes of the humanities are mostly uncharted territory. Little is known on the ways published research of humanist scholars defines areas of intellectual activity. An open question relates to the structural role of core literature: highly cited sources, naturally playing a disproportionate role in the definition of intellectual landscapes. We introduce four indicators in order to map the structural role played by core sources into connecting different areas of the intellectual landscape of citing publications (i.e. communities in the bibliographic coupling network). All indicators factor out the influence of degree distributions by internalizing a null configuration model. By considering several datasets focused on history, we show that two distinct structural actions are performed by the core literature: a global one, by connecting otherwise separated communities in the landscape, or a local one, by rising connectivity within communities. In our study, the global action is mainly performed by small sets of scholarly monographs, reference works and primary sources, while the rest of the core, and especially most journal articles, acts mostly locally

    Analytical Modeling and Performance Assessment of Micropulse Photon-counting Lidar System

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    The melting of polar ice sheets and evidence of global warming continue to remain prominent research interests among scientists. To better understand global volumetric change of ice sheets, NASA intends to launch Ice, Cloud and land Elevation Satellite-2 (ICESat-2) in 2017. ICESat-2 employs a high frequency photon-counting laser altimeter, which will provide significantly greater spatial sampling. However, the combined effects of sub-beam complex surfaces, as well as system effects on returning photon distribution have not been systematically studied. To better understand the effects of various system attributes and to help improve the theory behind lidar sensing of complex surfaces, an analytical model using a first principles 3-D Monte Carlo approach is developed to predict system performance. Based on the latest ICESat-2 design, this analytical model simulates photons which propagate from the laser transmitter to the scene, and reflected to the detector model. A radiometric model is also applied in the synthetic scene. Such an approach allows the study of surface elevation retrieval accuracy for landscapes, as well as surface reflectivities. It was found that ICESat-2 will have a higher precision on a smoother surface, and a surface with smaller diffuse albedo will on average result in smaller bias. Furthermore, an adaptive density-based algorithm is developed to detect the surface returns without any geometrical knowledge. This proposed approach is implemented using the aforementioned simulated data set, as well as airborne laser altimeter measurement. Qualitative and quantitative results are presented to show that smaller laser footprint, smoother surface, and lower noise rate will improve accuracy of ground height estimation. Meanwhile, reasonable detection accuracy can also be achieved in estimating both ground and canopy returns for data generated using Digital Imaging and Remote Sensing Image Generation (DIRSIG) model. This proposed approach was found to be generally applicable for surface and canopy finding from photon-counting laser altimeter data

    A Memory of Ice

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    "In the southern summer of 1972/73, the Glomar Challenger was the first vessel of the international Deep Sea Drilling Project to venture into the seas surrounding Antarctica, confronting severe weather and ever-present icebergs. A Memory of Ice presents the science and the excitement of that voyage in a manner readable for non-scientists. Woven into the modern story is the history of early explorers, scientists and navigators who had gone before into the Southern Ocean. The departure of the Glomar Challenger from Fremantle took place 100 years after the HMS Challenger weighed anchor from Portsmouth, England, at the start of its four-year voyage, sampling and dredging the world’s oceans. Sailing south, the Glomar Challenger crossed the path of James Cook’s HMS Resolution, then on its circumnavigation of Antarctica in search of the Great South Land. Encounters with Lieutenant Charles Wilkes of the US Exploring Expedition and Douglas Mawson of the Australasian Antarctic Expedition followed. In the Ross Sea, the voyages of the HMS Erebus and HMS Terror under James Clark Ross, with the young Joseph Hooker as botanist, were ever present. The story of the Glomar Challenger’s iconic voyage is largely told through the diaries of the author, then a young scientist experiencing science at sea for the first time. It weaves together the physical history of Antarctica with how we have come to our current knowledge of the polar continent. This is an attractive, lavishly illustrated and curiosity-satisfying read for the general public as well as for scholars of science.

    Echoes from the Deep:Inventorising shipwrecks at the national scale by the application of marine geophysics and the historical text

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    This book presents the results of a survey using a multibeam echosounder for the identification of the shipwrecks of the Irish Sea

    Volume 30 - 1999: Communication Divides: Perspectives on Supporting Information Bridges in the Geosciences - Proceedings of the 34th Meeting of the Geoscience Information Society

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    Proceedings of the 34th Meeting of the Geoscience Information Society held October 25-28, 1999 in Denver, Colorad

    The Intellectual Organisation of History

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    A tradition of scholarship discusses the characteristics of different areas of knowledge, in particular after modern academia compartmentalized them into disciplines. The academic approach is often put to question: are there two or more cultures? Is an ever-increasing specialization the only way to cope with information abundance or are holistic approaches helpful too? What is happening with the digital turn? If these questions are well studied for the sciences, our understanding of how the humanities might differ in their own respect is far less advanced. In particular, modern academia might foster specific patterns of specialization in the humanities. Eventually, the recent rise in the application of digital methods to research, known as the digital humanities, might be introducing structural adaptations through the development of shared research technologies and the advent of organizational practices such as the laboratory. It therefore seems timely and urgent to map the intellectual organization of the humanities. This investigation depends on few traits such as the level of codification, the degree of agreement among scholars, the level of coordination of their efforts. These characteristics can be studied by measuring their influence on the outcomes of scientific communication. In particular, this thesis focuses on history as a discipline using bibliometric methods. In order to explore history in its complexity, an approach to create collaborative citation indexes in the humanities is proposed, resulting in a new dataset comprising monographs, journal articles and citations to primary sources. Historians' publications were found to organize thematically and chronologically, sharing a limited set of core sources across small communities. Core sources act in two ways with respect to the intellectual organization: locally, by adding connectivity within communities, or globally as weak ties across communities. Over recent decades, fragmentation is on the rise in the intellectual networks of historians, and a comparison across a variety of specialisms from the human, natural and mathematical sciences revealed the fragility of such networks across the axes of citation and textual similarities. Humanists organize into more, smaller and scattered topical communities than scientists. A characterisation of history is eventually proposed. Historians produce new historiographical knowledge with a focus on evidence or interpretation. The former aims at providing the community with an agreed-upon factual resource. Interpretive work is instead mainly focused on creating novel perspectives. A second axe refers to two modes of exploration of new ideas: in-breadth, where novelty relates to adding new, previously unknown pieces to the mosaic, or in-depth, if novelty then happens by improving on previous results. All combinations possible, historians tend to focus on in-breadth interpretations, with the immediate consequence that growth accentuates intellectual fragmentation in the absence of further consolidating factors such as theory or technologies. Research on evidence might have a different impact by potentially scaling-up in the digital space, and in so doing influence the modes of interpretation in turn. This process is not dissimilar to the gradual rise in importance of research technologies and collaborative competition in the mathematical and natural sciences. This is perhaps the promise of the digital humanities

    The Grootfontein aquifer at Mahikeng, South Africa as hydro-social system

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    The Grootfontein aquifer is located about 20 km south east of Mahikeng, North West Province, South Africa, and currently supplies about 20% of Mahikeng’s water. Formed in weathered Malmani Subgroup dolomites, the aquifer contains good quality groundwater that could potentially supply more of Mahikeng’s water, as well as provide a strategic reserve of water for use during droughts. Over-abstraction of groundwater from the aquifer, mainly by irrigating farmers but also by the boreholes supplying Mahikeng, has caused the natural groundwater level to drop at a rate of about 0.4 m per year since the 1970s, leading to water level declines of as much as 28 m in parts of the aquifer. Although the Grootfontein aquifer is one of the best studied aquifers in South Africa hydrogeologically, efforts to address these declines since the 1970s have largely failed. This research combines hydrogeological evidence with social research (interviews and participant-observation) and the principles of Earth Stewardship Science to argue that the aquifer functions as a hydro-social system, and that institutional characteristics are the root cause of a collective inability to restore the aquifer to its full potential as a water resource. A sub-optimal and undesirable Nash equilibrium prevails, in which major groundwater users are unable or unwilling to reduce abstraction. The situation has significant cost and risk implications for the environmental, economic and social sectors, and contributes to insecurity, pessimism, inequality and mistrust. An effective local forum with appropriate powers, supported and mandated by the Department of Water and Sanitation, is needed to begin the work of dismantling the sub-optimal equilibrium to realise the potential of the Grootfontein aquifer. Such a forum would require a shared understanding of the hydrogeological mechanisms of the aquifer as well as its social and institutional functioning, since these influence each other in complex ways

    CPA\u27s handbook of fraud and commercial crime prevention

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    https://egrove.olemiss.edu/aicpa_guides/1819/thumbnail.jp

    Memory and Landscape

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    The North is changing at an unprecedented rate as industrial development and the climate crisis disrupt not only the environment but also long-standing relationships to the land and traditional means of livelihood. Memory and Landscape: Indigenous Responses to a Changing North explores the ways in which Indigenous peoples in the Arctic have adapted to challenging circumstances, including past cultural and environmental changes. In this beautifully illustrated volume, contributors document how Indigenous communities in Alaska, northern Canada, Greenland, and Siberia are seeking ways to maintain and strengthen their cultural identity while also embracing forces of disruption. Indigenous and non-Indigenous contributors bring together oral history and scholarly research from disciplines such as linguistics, archaeology, and ethnohistory. With an emphasis on Indigenous place names, this volume illuminates how the land—and the memories that are inextricably tied to it—continue to define Indigenous identity. The perspectives presented here also serve to underscore the value of Indigenous knowledge and its essential place in future studies of the Arctic. Contributions by Vinnie Baron, Hugh Brody, Kenneth Buck, Anna Bunce, Donald Butler, Michael A. Chenlov, Aron L. Crowell, Peter C. Dawson, Martha Dowsley, Robert Drozda, Gary Holton, Colleen Hughes, Peter Jacobs, Emily Kearney-Williams, Igor Krupnik, Apayo Moore, Murielle Nagy, Mark Nuttall, Evon Peter, Louann Rank, William E. Simeone, Felix St-Aubin, and Will Stolz.Publishe
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