59,721 research outputs found

    Geology of a Part of the Panamint Range, California

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    The Panamint Range is a tilted fault-block, uplifted probably in Tertiary time and rejuvenated by very complex recent faulting on the west. This great block is approximately 100 miles long, but the reconnaissance geologic map covers only a tract in the southern portion of the range about 21 miles from north to south. The oldest formation consists of a great thickness of undifferentiated and regionally metamorphosed rocks, embracing schists, gneisses, and marble, predominantly of sedimentary origin, injected by granitic rocks and cut by diabase dikes. These are overlain by less highly metamorphosed slaty schists and dolomitic limestones, separated by a nonconformity from a succession of rocks consisting largely of limestones, dolomites, and schists. The age of the rock formations is unknown, but is believed to range from pre-Cambrian to Lower Paleozoic. Structure within the range is not entirely clear and that of certain rock masses is indeterminable. The older rocks on the west slope show a westward dip of the foliation, while the younger formations, forming the crest of the range and the Death Valley side, dip gently eastward

    The Teacher and the Homosexual

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    Identification of Demand through Statistical Distribution Modeling for Improved Demand Forecasting

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    Demand functions for goods are generally cyclical in nature with characteristics such as trend or stochasticity. Most existing demand forecasting techniques in literature are designed to manage and forecast this type of demand functions. However, if the demand function is lumpy in nature, then the general demand forecasting techniques may fail given the unusual characteristics of the function. Proper identification of the underlying demand function and using the most appropriate forecasting technique becomes critical. In this paper, we will attempt to explore the key characteristics of the different types of demand function and relate them to known statistical distributions. By fitting statistical distributions to actual past demand data, we are then able to identify the correct demand functions, so that the the most appropriate forecasting technique can be applied to obtain improved forecasting results. We applied the methodology to a real case study to show the reduction in forecasting errors obtained

    Gaseous and dual-phase time projection chambers for imaging rare processes

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    Modern approaches to the detection and imaging of rare particle interactions through gaseous and dual-phase time projection chambers are discussed. We introduce and examine their basic working principles and enabling technological assets.Comment: Version accepted in NIM after small modifications. Quality of figures slightly reduced in pre-print due to arXiv restrictions on file siz

    Tracking Human Behavioural Consistency by Analysing Periodicity of Household Water Consumption

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    People are living longer than ever due to advances in healthcare, and this has prompted many healthcare providers to look towards remote patient care as a means to meet the needs of the future. It is now a priority to enable people to reside in their own homes rather than in overburdened facilities whenever possible. The increasing maturity of IoT technologies and the falling costs of connected sensors has made the deployment of remote healthcare at scale an increasingly attractive prospect. In this work we demonstrate that we can measure the consistency and regularity of the behaviour of a household using sensor readings generated from interaction with the home environment. We show that we can track changes in this behaviour regularity longitudinally and detect changes that may be related to significant life events or trends that may be medically significant. We achieve this using periodicity analysis on water usage readings sampled from the main household water meter every 15 minutes for over 8 months. We utilise an IoT Application Enablement Platform in conjunction with low cost LoRa-enabled sensors and a Low Power Wide Area Network in order to validate a data collection methodology that could be deployed at large scale in future. We envision the statistical methods described here being applied to data streams from the homes of elderly and at-risk groups, both as a means of early illness detection and for monitoring the well-being of those with known illnesses.Comment: 2019 2nd International Conference on Sensors, Signal and Image Processin

    Intermolecular interactions in the chiral and racemic forms of 3-hydroxy-2-(1-oxoisoindolin-2-yl)butanoic acid derived from threonine

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    The title compounds, C₁₂H₁₃NO₄, are derived from L-threonine and DL-threonine, respectively. Hydrogen bonding in the chiral derivative, (2S/3R)-3-hydroxy-2-(1-oxoisoindolin-2-yl)butanoic acid, consists of O-Hacid...Oalkyl-H...O=Cindole chains [O...O 2.659 (3) and 2.718 (3) Å], Csp³-H...O and three C-H...πarene interactions. In the (2R,3S/2S,3R) racemate, conventional carboxylic acid hydrogen bonding as cyclical (O-H...O=C)₂ [graph set R₂²(8)] is present, with Oalkyl-H...O=Cindole, Csp³-H...O and C-H...πarene interactions. The COOH group geometry differs between the two forms, with C-O, C=O, C-C-O and C-C=O bond lengths and angles of 1.322 (3) and 1.193 (3) Å, and 109.7 (2) and 125.4 (3)°, respectively, in the chiral structure, and 1.2961 (17) and 1.2210 (18) Å, and 113.29 (12) and 122.63 (13)°, respectively, in the racemate structure. The O-C=O angles of 124.9 (3) and 124.05 (14)° are similar. The differences arise from the contrasting COOH hydrogen-bonding environments in the two structures

    SSME Long-life Bearings

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    Hybrid hydrostatic/ball bearings for LH2 and LO2 service in turbopumps were studied as a means of improving speed and life capabilities. Four hybrid bearing configurations were designed with emphasis on achieving maximum stiffness and damping. Parallel load bearings were tested at steady-state and transient conditions with LH2 (externally fed) and LN2 (internally fed). The hydrostatic elements were tested with Freon 113 for empirical determination of dynamic characteristics. Tests using an eccentric journal for loading showed the externally and internally fed hydrostatic bearings to have significant separated coefficients of direct stiffness and damping. For the internally fed bearing, the strongly speed-dependent cross-coupling stiffness arising from fluid swirl, along with significant cross-coupling damping, resulted in low net effective stiffness and damping. The test method used can produce separated coefficients with a sufficiently elliptic journal orbit; otherwise, only net effective coefficients combining direct and cross-coupling terms can be determined. Testing with nonsynchronous excitation is recommended to avoid this restriction. Investigation of hard materials, including ceramics, is recommended as a means of eliminating the need for the rolling bearing for startup and shutdown support. The testing was performed in 1984 (LH2), 1985 (LN2) and 1985-86 (Freon)

    Energy absorption mechanisms during crack propagation in metal matrix composites

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    The stress distributions around individual fibers in a unidirectional boron/aluminum composite material subjected to axial and transverse loadings are being studied utilizing a generalized plane strain finite element analysis. This micromechanics analysis was modified to permit the analysis of longitudinal sections, and also to incorporate crack initiation and propagation. The analysis fully models the elastoplastic response of the aluminum matrix, as well as temperature dependent material properties and thermal stress effects. The micromechanics analysis modifications are described, and numerical results are given for both longitudinal and transverse models loaded into the inelastic range, to first failure. Included are initially cracked fiber models

    B-52 control configured vehicles: Flight test results

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    Recently completed B-52 Control Configured Vehicles (CCV) flight testing is summarized, and results are compared to analytical predictions. Results are presented for five CCV system concepts: ride control, maneuver load control, flutter mode control, augmented stability, and fatigue reduction. Test results confirm analytical predictions and show that CCV system concepts achieve performance goals when operated individually or collectively
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