2,433 research outputs found

    Analysis of Alaska's water use act and its interaction with federal reserved water rights

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    Since the passage of Alaska's Water Use Act in 1966, the amount of water required by Alaska's growing population and resource development has increased very rapidly. The need to review the adequacy of existing water use laws and their administration has been expressed both by those trying to comply with regulations and by those attempting to enforce standards and permit requirements. This report summarizes the historical development of the doctrine of prior appropriation in Alaska. The statutory authority, regulations, and administration of Alaska's Water Use Act by the Alaska Department of Natural Resources are presented. Overlapping state agency authorities are discussed, and existing and proposed regulations are analyzed. The application of federal reserved water rights to Alaska and the status of quantification of these rights is explained. The report presents options for the State of Alaska to manage water use on federal lands, and for preserving minimum stream flows for maintenance of fish and wildlife habitats.The work upon which this report is based was supported by funds (Project A-059-ALAS) provided by the U.S. Department of Interior, Office of Water Research and Technology, as authorized under the Water Resources Research Act of 1964, as amended

    Effect of polymer properties and adherend surfaces on adhesion

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    High temperature polymer surface characteristics associated with joint strength were evaluated. Selected samples represented composite adherends, aluminum filler and fiber glass carrier cloth. Detailed analysis of fractured joint surfaces revealed unique characteristics typical of the specific adhesive formulations and test conditions. A fracture mechanism model was developed for correlating macroscopic shear strength and microstructure of fracture surfaces. Applications were made to unpublished data on polyimides and fluoropolymers

    A fundamental approach to adhesion: Synthesis, surface analysis, thermodynamics and mechanics

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    The effects of composites as adherends was studied. Several other variables were studied by fractography: aluminum powder adhesive filler, fiber glass cloth scrim or adhesive carrier, new adhesives PPQ-413 and LARC-13, and strength-test temperature. When the new results were juxtaposed with previous work, it appeared that complex interactions between adhesive, adherend, bonding, and testing conditions govern the observed strength and fracture-surface features. The design parameters likely to have a significant effect upon strength-test results are listed

    Analysis of Meteorological Data Obtained During Flight in a Supercooled Stratiform Cloud of High Liquid-Water Content

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    Flight icing-rate data obtained in a dense and. abnormally deep supercooled stratiform cloud system indicated the existence of liquid-water contents generally exceeding values in amount and extent previously reported over the midwestern sections of the United States. Additional information obtained during descent through a part of the cloud system indicated liquid-water contents that significantly exceeded theoretical values, especially near the middle of the cloud layer.. The growth of cloud droplets to sizes that resulted in sedimentation from the upper portions of the cloud is considered to be a possible cause of the high water contents near the center of the cloud layer. Flight measurements of the vertical temperature distribution in the cloud layer indicated a rate of change of temperature with altitude exceeding that of the moist adiabatic lapse rate. This excessive rate of change is considered to have contributed to the severity of the condition

    Convective instability and transient growth in steady and pulsatile stenotic flows

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    We show that suitable initial disturbances to steady or long-period pulsatile flows in a straight tube with an axisymmetric 75%-occlusion stenosis can produce very large transient energy growths. The global optimal disturbances to an initially axisymmetric state found by linear analyses are three-dimensional wave packets that produce localized sinuous convective instability in extended shear layers. In pulsatile flow, initial conditions that trigger the largest disturbances are either initiated at, or advect to, the separating shear layer at the stenosis in phase with peak systolic flow. Movies are available with the online version of the paper

    Convective instability and transient growth in flow over a backward-facing step

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    Transient energy growths of two- and three-dimensional optimal linear perturbations to two-dimensional flow in a rectangular backward-facing-step geometry with expansion ratio two are presented. Reynolds numbers based on the step height and peak inflow speed are considered in the range 0–500, which is below the value for the onset of three-dimensional asymptotic instability. As is well known, the flow has a strong local convective instability, and the maximum linear transient energy growth values computed here are of order 80×103 at Re = 500. The critical Reynolds number below which there is no growth over any time interval is determined to be Re = 57.7 in the two-dimensional case. The centroidal location of the energy distribution for maximum transient growth is typically downstream of all the stagnation/reattachment points of the steady base flow. Sub-optimal transient modes are also computed and discussed. A direct study of weakly nonlinear effects demonstrates that nonlinearity is stablizing at Re = 500. The optimal three-dimensional disturbances have spanwise wavelength of order ten step heights. Though they have slightly larger growths than two-dimensional cases, they are broadly similar in character. When the inflow of the full nonlinear system is perturbed with white noise, narrowband random velocity perturbations are observed in the downstream channel at locations corresponding to maximum linear transient growth. The centre frequency of this response matches that computed from the streamwise wavelength and mean advection speed of the predicted optimal disturbance. Linkage between the response of the driven flow and the optimal disturbance is further demonstrated by a partition of response energy into velocity components

    What Are Kinship Terminologies, and Why Do We Care? A Computational Approach to Analyzing Symbolic Domains

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    Kinship is a fundamental feature and basis of human societies. We describe a set of computational tools and services, the Kinship Algebra Modeler, and the logic that underlies these. These were developed to improve how we understand both the fundamental facts of kinship, and how people use kinship as a resource in their lives. Mathematical formalism applied to cultural concepts is more than an exercise in model building, as it provides a way to represent and explore logical consistency and implications. The logic underlying kinship is explored here through the kin term computations made by users of a terminology when computing the kinship relation one person has to another by referring to a third person for whom each has a kin term relationship. Kinship Algebra Modeler provides a set of tools, services and an architecture to explore kinship terminologies and their properties in an accessible manner

    Crystal structure analysis of intermetallic compounds

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    Study concerns crystal structures and lattice parameters for a number of new intermetallic compounds. Crystal structure data have been collected on equiatomic compounds, formed between an element of the Sc, Ti, V, or Cr group and an element of the Co or Ni group. The data, obtained by conventional methods, are presented in an easily usable tabular form

    A Study to Determine the Order in Which Major Tools are Desired by Industrial Arts Instructors in South Dakota

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    The primary objective of this study was to formulate a guide for school administrators or industrial arts instructors to consult when deciding which major tools are necessary for an industrial arts program. The study concerned the following factors: the order of preference of major tools, the size of tools desired

    Easement Come, Easment Go - The Cemetery Access Easement: The Exemption to the Right to Exclude Whose Time Has Come to Facilitate the Preservation of Nineteenth-Century Texas Family Cemeteries

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    This Article discusses the cemetery access easement and access agreements under the lens of an emerging modern theoretical approach—the Social Morality Theory of Property Law. Part II reviews the history of public and private memorials in Texas, preservation efforts of nineteenth-century cemeteries, and other significant Texas historical sites. Part III discusses the cemetery access easement under current Texas law and regulatory schemes. Part IV discusses the obstacles of awareness and access as the greatest threats to the current and future status of nineteenth-century Texas family cemeteries on rural private land. Finally, Part V proposes incentives, approaches, and recommendations to strengthen Texas cemetery access easement law in order to facilitate the preservation of nineteenth-century Texas family cemeteries on rural private land
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