12,066 research outputs found

    Kinesimetric method and apparatus

    Get PDF
    Apparatus and method for the determination of functional capability of bodies are disclosed. Reach as well as velocity, acceleration and force generation at various positions may be determined for a body by a three dimensional kinesimeter equipped with an ergometer. A general data package indicative of performance potential of a subject body or collection of bodies is provided for interfacing with data characteristics of various environments

    Fast food restaurant locations : could they be \u27supersizing\u27 local communities?

    Full text link
    This review examines the current state of knowledge related to the location of fast food restaurants. Previous studies have revealed some communities are more exposed to fast food restaurants. However, the influence of increased exposure to fast food on dietary behaviours remains unresolved. This is identified as an area of priority for future research.<br /

    Method and apparatus for simulating gravitational forces on a living organism

    Get PDF
    A method and apparatus for simulating gravitational forces on a living organism wherein a series of negative pressures are externally applied to successive length-wise sections of a lower limb of the organism. The pressures decreasing progressively with distance of said limb sections from the heart of the organism. A casing defines a chamber adapted to contain the limb of the organism and is rigidified to resist collapse upon the application of negative pressures to the interior of the chamber. Seals extend inwardly from the casing for effective engagement with the limb of the organism and, in cooperation with the limb, subdivide the chamber into a plurality of compartments each in negative pressure communicating relation with the limb

    The climatological relationships between wind and solar energy supply in Britain

    Get PDF
    We use reanalysis data to investigate the daily co-variability of wind and solar irradiance in Britain, and its implications for renewable energy supply balancing. The joint distribution of daily-mean wind speeds and irradiances shows that irradiance has a much stronger seasonal cycle than wind, due to the rotational tilt of the Earth. Irradiance is weakly anticorrelated with wind speed throughout the year (0.4ρ0.2-0.4 \lesssim \rho \lesssim -0.2): there is a weak tendency for windy days to be cloudier. This is particularly true in Atlantic-facing regions (western Scotland, south-west England). The east coast of Britain has the weakest anticorrelation, particularly in winter, primarily associated with a relative increase in the frequency of clear-but-windy days. We also consider the variability in total power output from onshore wind turbines and solar photovoltaic panels. In all months, daily variability in total power is always reduced by incorporating solar capacity. The scenario with the least seasonal variability is approximately 70%-solar to 30%-wind. This work emphasises the importance of considering the full distribution of daily behaviour rather than relying on long-term average relationships or correlations. In particular, the anticorrelation between wind and solar power in Britain cannot solely be relied upon to produce a well-balanced energy supply.Comment: 19 pages, 19 figures, accepted for publication in Renewable Energy. Text updated to match accepted version (one footnote added, some references corrected

    A method of isolating treadmill shock and vibration on spacecraft

    Get PDF
    A major problem is currently felt to exist in the implementation of materials processing on a spacecraft. Crystal growers place requirements of one micro-g or less on the vehicle. Simple math produces startling figures for such a restriction e.g., for each ton of vehicle mass with 10(-6) g acceleration limit; Perturbing Force limit, F = .002 lb. For each 10(5) lbs F = 0.1 lb. For each 10(6) lbs F = 1.0 lb. Forces generated by normal human movement on spacecraft of 5x10(5) pounds weight are on an order-of-magnitude greater than allowed by this specification and forces generated by locomotion on a treadmill are more than two orders-of-magnitude greater. Other exercises and normal onboard functions generate forces in between. To accommodate many essential functions it is obvious that even on a vehicle as large as Space Station, a reduction of more than two orders of magnitude in force is required. Commonly used passive shock and vibration isolation devices are complex, heavy, and also would have difficulty meeting the requirements. However, by a new arrangement, adequate isolation can be obtained. Isolation of the treadmill will be treated since it is considered the most significant disturbance at this time

    A computer program incorporating fatigue and fracture criteria in the preliminary design of transport aircraft: An evaluation

    Get PDF
    The APAS program a multistation structural synthesis procedure developed to evaluate material, geometry, and configuration with various design criteria usually considered for the primary structure of transport aircraft is described and evaluated. Recommendations to improve accuracy and extend the capabilities of the APAS program are given. Flow diagrams are included

    Using the Twentieth Century Reanalysis to assess climate variability for the European wind industry

    Full text link
    We characterise the long-term variability of European near-surface wind speeds using 142 years of data from the Twentieth Century Reanalysis (20CR), and consider the potential of such long-baseline climate data sets for wind energy applications. The low resolution of the 20CR would severely restrict its use on its own for wind farm site-screening. We therefore perform a simple statistical calibration to link it to the higher-resolution ERA-Interim data set (ERAI), such that the adjusted 20CR data has the same wind speed distribution at each location as ERAI during their common period. Using this corrected 20CR data set, wind speeds and variability are characterised in terms of the long-term mean, standard deviation, and corresponding trends. Many regions of interest show extremely weak trends on century timescales, but contain large multidecadal variability. Since reanalyses such as ERAI are often used to provide the background climatology for wind farm site assessments, but contain only a few decades of data, our results can be used as a way of incorporating decadal-scale wind climate variability into such studies, allowing investment risks for wind farms to be reduced.Comment: 18 pages, plus 4 page supplementary information included here as Appendix D. This is the authors' corrected version, matching the content of the version accepted by Theoretical and Applied Climatolog

    Comparison of NASTRAN and MITAS nonlinear thermal analyses of a convectively cooled structure

    Get PDF
    Comparative steady state nonlinear thermal analyses of a scramjet fuel injection strut are presented. The analyses were performed using the NASTRAN finite element program and MITAS, a lumped-parameter thermal analyzer. The strut is subjected to aerodynamic heating on two sides and is internally cooled by hydrogen flowing from internal manifolds through heat exchangers bonded to the primary structure. Based on coolant temperatures determined by MITAS, NASTRAN predicted temperature distributions throughout the strut which were in close agreement with similar MITAS predictions

    Hole cutter

    Get PDF
    An adjustable hole cutter is described for use in forming circular openings in workpieces. The hole cutter is characterized by a mount of a substantially planar configuration, positionable into a plane paralleling the working plane of a selected workpiece. It also contains a shaft for imparting rotary motion to the mount about an axis of rotation normally related to the working plane, a plurality of stabilizing struts for resiliently supporting the mount in parallelism with the working plane as rotary motion is imparted thereto, a drill bit for drilling a pilot hole concentric with the axis of rotation, and an elongated cutting tool adjustably seated within a radially extended slot

    Integrated thermal-structural analysis of large space structures

    Get PDF
    Optimum performance of large space antennas requires very fine control of the shape of the antenna surface since the shape affects both frequency control and pointing accuracy. A significant factor affecting the antenna shape is the temperature of the structure and the resulting deformation. To accurately predict the temperature of the structure, it is necessary first to accurately predict thermal loads. As the structure orbits the Earth, the thermal loads change constantly so that the thermal-structural response varies continuously throughout the orbit. The results from recent applications of integrated finite element methodology to heat load determination and thermal-structural analysis of large space structures are given. Four areas are concentrated on: (1) the characteristics of the integrated finite element methodology, (2) fundamentals of orbital heat load calculation, (3) description and comparison of some radiation finite elements, and (4) application of the integrated finite-element approach to the thermal-structural analysis of an orbiting truss structure
    corecore