13,583 research outputs found

    Comparing the Profitability of Beef Production Enterprises in North Dakota

    Get PDF
    Agricultural Finance, Production Economics,

    Single stage, low noise, advanced technology fan. Volume 1: Aerodynamic design

    Get PDF
    The aerodynamic design for a half-scale fan vehicle, which would have application on an advanced transport aircraft, is described. The single stage advanced technology fan was designed to a pressure ratio of 1.8 at a tip speed of 503 m/sec 11,650 ft/sec). The fan and booster components are designed in a scale model flow size convenient for testing with existing facility and vehicle hardware. The design corrected flow per unit annulus area at the fan face is 215 kg/sec sq m (44.0 lb m/sec sq ft) with a hub-tip ratio of 0.38 at the leading edge of the fan rotor. This results in an inlet corrected airflow of 117.9 kg/sec (259.9 lb m/sec) for the selected rotor tip diameter if 90.37 cm (35.58 in.). The variable geometry inlet is designed utilizing a combination of high throat Mach number and acoustic treatment in the inlet diffuser for noise suppression (hybrid inlet). A variable fan exhaust nozzle was assumed in conjunction with the variable inlet throat area to limit the required area change of the inlet throat at approach and hence limit the overall diffusion and inlet length. The fan exit duct design was primarily influenced by acoustic requirements, including length of suppressor wall treatment; length, thickness and position on a duct splitter for additional suppressor treatment; and duct surface Mach numbers

    Scoping a public health impact assessment of aquaculture with particular reference to tilapia in the UK

    Get PDF
    Background. The paper explores shaping public health impact assessment tools for tilapia, a novel emergent aquaculture sector in the UK. This Research Council’s UK Rural Economy and Land Use project embraces technical, public health, and marketing perspectives scoping tools to assess possible impacts of the activity. Globally, aquaculture produced over 65 million tonnes of food in 2008 and will grow significantly requiring apposite global public health impact assessment tools.<p></p> Methods. Quantitative and qualitative methods incorporated data from a tridisciplinary literature. Holistic tools scoped tilapia farming impact assessments. Laboratory-based tilapia production generated data on impacts in UK and Thailand along with 11 UK focus groups involving 90 consumers, 30 interviews and site visits, 9 visits to UK tilapia growers and 2 in The Netherlands.<p></p> Results. The feasibility, challenges, strengths, and weaknesses of creating a tilapia Public Health Impact Assessment are analysed. Occupational and environmental health benefits and risks attached to tilapia production were identified.<p></p> Conclusions. Scoping public health impacts of tilapia production is possible at different levels and forms for producers, retailers, consumers, civil society and governmental bodies that may contribute to complex and interrelated public health assessments of aquaculture projects. Our assessment framework constitutes an innovatory perspective in the field

    The measurement of low pay in the UK labour force survey

    No full text
    Consideration of the National Minimum Wage requires estimates of the distribution of hourly pay. The UK Labour Force Survey (LFS) is a key source of such estimates. The approach most frequently adopted by researchers has been to measure hourly earnings from several questions on pay and hours. The Office for National Statistics is now applying a new approach, based on an alternative more direct measurement introduced in March 1999. These two measures do not produce identical values and this paper investigates sources of discrepancies and concludes that the new variable is more accurate. The difficulty with using the new variable is that it is only available on a subset of respondents. An approach is developed in which missing values of the new variable are replaced by imputed values. The assumptions underlying this imputation approach and results of applying it to LFS data are presented. The relation to weighting approaches is also discussed

    Hot melt adhesive attachment pad

    Get PDF
    A hot melt adhesive attachment pad for releasably securing distinct elements together is described which is particularly useful in the construction industry or a spatial vacuum environment. The attachment pad consists primarily of a cloth selectively impregnated with a charge of hot melt adhesive, a thermo-foil heater, and a thermo-cooler. These components are securely mounted in a mounting assembly. In operation, the operator activates the heating cycle transforming the hot melt adhesive to a substantially liquid state, positions the pad against the attachment surface, and activates the cooling cycle solidifying the adhesive and forming a strong, releasable bond

    Paper Session III-D - The Advanced Lift Support Automated Robotic Manipulator (ALSARM) Project

    Get PDF
    The National Aeronautics and Space Administration (NASA) Biomedical Program Office (JJ-G), Design Engineering Advanced Systems and Analysis Division (DM-ASD), and the University of Central Florida (UCF) Department of Mechanical and Aerospace Engineering (MAE) are currently working together on the design, fabrication, and implementation of the Advanced Life Support Automated Remote Manipulator (ALSARM). Once completed, the ALSARM robotic arm will be integrated into the Controlled Ecological Life Support Systems (CELSS) Breadboard Project Biomass Production Chamber (BPC), located at the Life Sciences Support Facility (LSSF) at Kennedy Space Center (KSC). The goal of this collaborative effort between NASA and UCF is twofold: first, it provides undergraduate engineering students with the opportunity to gain vital experience in the “real world” of engineering design. Second, it introduces KSC’s next step in the development of a life support system to be used on a future human-tended mission wherein regular resupply from Earth would be impractical if not impossible
    corecore