3,544 research outputs found

    Assessment of flood damage in Arizona by means of ERTS-1 imagery

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    ERTS-1 MSS images clearly show two important effects of a large flood in southeastern Arizona - the extent of inundation and the areas affected by servere sediment deposition and erosion - although the images were made a week and a half after the flood. On October 20 and 21, 1972, the upper Gila River had its third-largest flood on record. Peak flows attained about 42,000 and 82,000 cubic feet a second at Duncan and Safford, Arizona, respectively. The first ERTS-1 images after the flood were made on November 1 and 2. The inundated area is best displayed on the infrared bands, particularly on band 7, where it appears as a belt along the river that is distinctly darker than adjoining parts of the flood plain. This dark belt does not appear on ERTS images that predate the flood. Presumably the low infrared reflectance of this belt is caused by still-moist soil and by flood-stressed vegetation. Inundation limits mapped from ERTS imagery agree well with those obtained by aerial photography during the flood and by ground surveys

    Application of ERTS-1 imagery to detecting and mapping modern erosion features, and to monitoring erosional changes, in southern Arizona

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    The author has identified the following significant results. ERTS-1 multispectral images have been used, without additional data, to prepare three maps at 1:1 million scale of the 18,000 sq. mi. project area: (1) modern (post-1890 A. D.) arroyos and channels; (2) types of stream channels; and (3) potential erodibility of soils; surficial deposits, and bedrock. Also completed was the collection and compilation of ground truth geologic, soil, and hydrologic data. Field studies to obtain ground control for the photointerpretive mapping include: (1) measurements, at many sites, of the depth, width, and channel characteristics of arroyos and gullies, and cross profiles of stream channels, flood plains, and Holocene terraces; and (2) stratigraphic measurements of the Holocene alluvial deposits. Significant conclusions from these extensive stratigraphic studies are: Slow deposition of sediment was the dominant process on stream lowlands throughout the project area for at least 2000 years prior to 1890 A.D. The deposition was broken by only two relatively brief and minor erosional episodes of regional importance, when channels no more than a third of the depth of modern channels were cut. The modern erosion has produced within about 80 years substantially more and larger arroyos than any erosion episode during the last 2000 years, and the end is not in sight

    New Records of Michigan Cicadidae (Homoptera), With Notes on the Use of Songs to Monitor Range Changes

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    We present records of Diceroprocta vitripennis, Tibicen chloromera, and Tibicen pruinosa (new state record) in Michigan. Monitoring geographic range changes and population size differences by song suggests several population situations for cicadas: (1) sizable populations in most areas of apparently good habitat; (2) widely separated single individuals or small populations on the edges of populated regions, representing range extensions that may be of limited duration; (3) one or a few individuals present only once, probably transferred in soil on roots, and ultimately unsuccessful. Species- specific calling songs allow sensitive measurement of species\u27 range changes

    Slide Stabilization With Gravel Trenches

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    A different method of slide stabilization using gravel trenches is described. The design, construction, and performance monitoring of the gravel trenches are discussed together with a history of the slide, description of the soils, and mechanism of failure. The applications and limitations of this method of slide stabilization are also evaluated

    Measurement and simulation of anisotropic magnetoresistance in single GaAs/MnAs core/shell nanowires

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    We report four probe measurements of the low field magnetoresistance in single core/shell GaAs/MnAs nanowires synthesized by molecular beam epitaxy, demonstrating clear signatures of anisotropic magnetoresistance that track the field-dependent magnetization. A comparison with micromagnetic simulations reveals that the principal characteristics of the magnetoresistance data can be unambiguously attributed to the nanowire segments with a zinc blende GaAs core. The direct correlation between magnetoresistance, magnetization and crystal structure provides a powerful means of characterizing individual hybrid ferromagnet/semiconductor nanostructures.Comment: Submitted to Applied Physics Letters; some typos corrected and a defective figure replace

    Modern trends in the retail ice cream store

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    Cover title.Includes bibliographical references

    Naturopathy as a model of prevention-oriented, patient-centered primary care: A disruptive innovation in health care

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    © 2019 by the authors. Licensee MDPI, Basel, Switzerland. Background and Objective: The concept of a “disruptive innovation,” recently extended to health care, refers to an emerging technology that represents a new market force combined with a new value system, that eventually displaces some, or all, of the current leading “stakeholders, products and strategic alliances.” Naturopathy is a distinct system of traditional and complementary medicine recognized by theWorld Health Organization (WHO), emerging as a model of primary care. The objective here is to describe Naturopathy in the context of the criteria for a disruptive innovation. Methods: An evidence synthesis was conducted to evaluate Naturopathy as a potentially disruptive technology according to the defining criteria established by leading economists and health technology experts: (1) The innovation must cure disease; (2) must transform the way medicine is practiced; or (3) have an impact that could be disruptive or sustaining, depending on how it is integrated into the current healthcare marketplace. Results: The fact that Naturopathy de-emphasizes prescription drug and surgical interventions in favor of nonpharmacological health promotion and self-care could disrupt the present economic model that fuels health care costs. The patient-centered orientation of Naturopathy, combined with an emphasis on preventive behaviors and popular complementary and integrative health services like natural products, mind and body therapies, and other therapies not widely represented in current primary care models increase the likelihood for disruption. Conclusions: Because of its patient-centered approach and emphasis on prevention, naturopathy may disrupt or remain a durable presence in healthcare delivery depending on policymaker decisions

    Fast Fourier Optimization: Sparsity Matters

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    Many interesting and fundamentally practical optimization problems, ranging from optics, to signal processing, to radar and acoustics, involve constraints on the Fourier transform of a function. It is well-known that the {\em fast Fourier transform} (fft) is a recursive algorithm that can dramatically improve the efficiency for computing the discrete Fourier transform. However, because it is recursive, it is difficult to embed into a linear optimization problem. In this paper, we explain the main idea behind the fast Fourier transform and show how to adapt it in such a manner as to make it encodable as constraints in an optimization problem. We demonstrate a real-world problem from the field of high-contrast imaging. On this problem, dramatic improvements are translated to an ability to solve problems with a much finer grid of discretized points. As we shall show, in general, the "fast Fourier" version of the optimization constraints produces a larger but sparser constraint matrix and therefore one can think of the fast Fourier transform as a method of sparsifying the constraints in an optimization problem, which is usually a good thing.Comment: 16 pages, 8 figure
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