32,849 research outputs found

    The Origins and Early History of the Steamer Albatross, 1880–18

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    Spencer Fullerton Baird (Fig. 1), a noted systematic zoologist and builder of scientific institutions in 19th century America, persuaded the U.S. Congress to establish the United States Commission of Fish and Fisheries1 in March 1871. At that time, Baird was Assistant Secretary of the Smithsonian Institution. Following the death of Joseph Henry in 1878, he became head of the institution, a position he held until his own demise in 1887. In addition to his many duties as a Smithsonian official, including his prominent role in developing the Smithsonian’s Federally funded National Museum as the repository for governmental scientific collections, Baird directed the Fish Commission from 1871 until 1887. The Fish Commission’s original mission was to determine the reasons and remedies for the apparent decline of American fisheries off southern New England as well as other parts of the United States. In 1872, Congress further directed the Commission to begin a large fish hatching program aimed at increasing the supply of American food

    Sleeved damper limits spring surging

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    Damping device limits spring surging in delicate instrumentation subjected to shock loading to tolerable limits. The device consists of a spiral formed plastic member interleaved between the spring coils in the same helix configuration

    Physical environment, nutrient budget, and ecology of Lake Moana-nui, Tokoroa

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    This report is based on fortnightly monitoring data collected over a 14 month period from November 2000 to January 2002 and a survey of the lake bathymetry and vegetation distribution. The project also included a detailed investigation into the associations between macroinvertebrates and the native and exotic plants in the lake, and experiments evaluating the effects of the large populations of the water flea Simocephalus vetulus that the lake maintains on algal concentrations and therefore water clarity. The aim of this report is to present and discuss the results of the monitoring, surveys, and experiments in order to make recommendations for the future management and health of Lake Moana-nui

    Dynamical transition for a particle in a squared Gaussian potential

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    We study the problem of a Brownian particle diffusing in finite dimensions in a potential given by ψ=ϕ2/2\psi= \phi^2/2 where ϕ\phi is Gaussian random field. Exact results for the diffusion constant in the high temperature phase are given in one and two dimensions and it is shown to vanish in a power-law fashion at the dynamical transition temperature. Our results are confronted with numerical simulations where the Gaussian field is constructed, in a standard way, as a sum over random Fourier modes. We show that when the number of Fourier modes is finite the low temperature diffusion constant becomes non-zero and has an Arrhenius form. Thus we have a simple model with a fully understood finite size scaling theory for the dynamical transition. In addition we analyse the nature of the anomalous diffusion in the low temperature regime and show that the anomalous exponent agrees with that predicted by a trap model.Comment: 18 pages, 4 figures .eps, JPA styl

    Studies of Birds and Mammals in the Baird and Schwatka Mountains, Alaska

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    In 1963 a joint University of Alaska-Smithsonian Institution crew worked at five locations in the Baird and Schwatka mountains in northwestern Alaska, conducting an ecological reconnaissance and faunal and floral inventory. Standard methods of observation and collection were used. Camps in the Kobuk drainage were located in the Redstone River valley and at Walker Lake, both on the margin of the taiga. The Noatak valley was represented by one camp each in the lower, middle, and upper reaches of the river, all in tundra. A summary of pre-1963 ornithological work in the region is presented. Significant records of distribution and/or breeding were obtained for the following birds: Podiceps grisegena, Anas platyrhynchos, Aythya valisineria, Histrionicus histrionicus, Melanitta perspicillata, Mergus merganser, Aphrizia virgata, Bartramia longicauda, Actitis macularia, Tringa flavipes, Phalaropus fuficarius, Lobipes lobatus, Larus hyperboreus,Xema sabini, Sayornis saya, Nuttalornis borealis, Eremophilia alpestris, Tachycineta thalassina, Riparia riparia, Petrochelidon pyrrhonota, Phylloscopus borealis, Dendroica petechia, Leucosticte tephrocotis, Zonotrichia atricapilla, Calcarius pictus; and the mammal, Spermophilus undulatus. Good series of Cletihrionomys rutilius (350) and Microtus miurus (147) have been deposited in the University of Alaska Museum. Severe doubt has been raised regarding the validity of the standard three-night trap grid for population estimation under wet conditions in arctic areas

    Strata: A Geophotographic Fiction

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    What if any relevance does Robert Smithson’s conceptual writing have in provoking an ontological discussion to expand conceptual thinking on artistic representations in contemporary art? I hope to open up creative geopolitical imaginaries to expand on processes of understanding, through the creation of a recent archival history of materiality. I would propose an elaboration of Smithson’s idea of ‘speculative geology’ referred to in his project, ‘Strata: a Geophotographic Fiction, (1970), as setting the parameter for my archive. ‘Strata’ is described as a homage to the artistic imagination of geological time and the inevitable accumulation of entropy and decay. I was struck by the artist’s statement that his materials were of the earth but his subject was the immensity of geologic time. Additionally, the paradigmatic potential of art to provide shorthand access to the subject of representation of the Anthropocene is discussed by K. Robertson in her article titled, ‘Plastiglomerate’. The on-going archive which I am in the process of compiling will situate itself in ‘Land Art’ pieces such as the work of Robert Smithson, to ‘Plastiglomerates’, as well as create a methodology for adding to the archive through the analysis of materiality, using Kent International airport as a prototype. Through my research vehicle ARCA I recorded the now decommissioned Kent International Airport, specifically the 2749m runway built during the Second World War; too costly to dig up, sitting on a substrate of a depth of 3 to 5 metres. As proposals for its future are debated, the question arises as to how the nature of the materiality of the site and a consideration for its place in a geological time span, might influence a proposal for its future use? My own methodology, which would add to the documentation, draws on forensic mapping techniques, thereby creating an empirical build-up of knowledge through methods used in archaeological digs, computational photography & Reflectance Transformation Imaging (RTI). These techniques are more commonly used in the field of forensic science, for example in imaging footprint and tyre mark. I will build up a taxonomy of objects which are read and analysed as relational to their environment, thereby situated in the material, but relational to a more expanded field thereby addressing the transcalar
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