33,535 research outputs found

    Farming Systems in the Central West of NSW: An Economic Analysis

    Get PDF
    The objectives of this report have been to describe important farming systems in the Central West of NSW, to gain some insights into current financial performance and to examine in more detail the role of pastures in these farming systems at a time when the profitability of wool growing has been low relative to grain growing. While farms and farming systems vary considerably across the region, a majority can be broadly grouped into a mixed livestock and cropping category. Although there is also significant variability within this category, two representative farms and farming systems were developed for the region with the assistance from a small group of farmers and extension staff from NSW Agriculture. One represents the farms and farming systems east of Condobolin and the other represents the farms and farming systems to the west of Condobolin. Whole-farm budget models have been developed for each to provide a description of the farms in this region and an indication of their current profitability. They are useful to give an indication of how farm income might be altered by the introduction of some new technology, a new enterprise such a pulse crop, or an alternative management practice. This report presents some examples of their application but importantly it has provided a template for the development of additional whole-farm budgets for alternative farming systems in this and other regions. Using the whole-farm budget representing farms east of Condobolin, and a linear programming model, PRISM Condobolin, this report shows that the optimal length of pasture is fairly insensitive to changing market signals for both cropping and livestock commodities. It also shows that although length of pasture is insensitive, the optimal mix of enterprises does change, highlighting the importance of considering the interactions between enterprises in whole-farm analysis.Industrial Organization, Production Economics,

    Toolflows for Mapping Convolutional Neural Networks on FPGAs: A Survey and Future Directions

    Get PDF
    In the past decade, Convolutional Neural Networks (CNNs) have demonstrated state-of-the-art performance in various Artificial Intelligence tasks. To accelerate the experimentation and development of CNNs, several software frameworks have been released, primarily targeting power-hungry CPUs and GPUs. In this context, reconfigurable hardware in the form of FPGAs constitutes a potential alternative platform that can be integrated in the existing deep learning ecosystem to provide a tunable balance between performance, power consumption and programmability. In this paper, a survey of the existing CNN-to-FPGA toolflows is presented, comprising a comparative study of their key characteristics which include the supported applications, architectural choices, design space exploration methods and achieved performance. Moreover, major challenges and objectives introduced by the latest trends in CNN algorithmic research are identified and presented. Finally, a uniform evaluation methodology is proposed, aiming at the comprehensive, complete and in-depth evaluation of CNN-to-FPGA toolflows.Comment: Accepted for publication at the ACM Computing Surveys (CSUR) journal, 201

    Design Considerations for a Ground-based Transit Search for Habitable Planets Orbiting M dwarfs

    Full text link
    By targeting nearby M dwarfs, a transit search using modest equipment is capable of discovering planets as small as 2 Earth radii in the habitable zones of their host stars. The MEarth Project, a future transit search, aims to employ a network of ground-based robotic telescopes to monitor M dwarfs in the northern hemisphere with sufficient precision and cadence to detect such planets. Here we investigate the design requirements for the MEarth Project. We evaluate the optimal bandpass, and the necessary field of view, telescope aperture, and telescope time allocation on a star-by-star basis, as is possible for the well-characterized nearby M dwarfs. Through these considerations, 1,976 late M dwarfs (R < 0.33 Rsun) emerge as favorable targets for transit monitoring. Based on an observational cadence and on total telescope time allocation tailored to recover 90% of transit signals from planets in habitable zone orbits, we find that a network of ten 30 cm telescopes could survey these 1,976 M dwarfs in less than 3 years. A null result from this survey would set an upper limit (at 99% confidence) of 17% for the rate of occurrence of planets larger than 2 Earth radii in the habitable zones of late M dwarfs, and even stronger constraints for planets lying closer than the habitable zone. If the true occurrence rate of habitable planets is 10%, the expected yield would be 2.6 planets.Comment: accepted to PAS

    High-Throughput Computing on High-Performance Platforms: A Case Study

    Full text link
    The computing systems used by LHC experiments has historically consisted of the federation of hundreds to thousands of distributed resources, ranging from small to mid-size resource. In spite of the impressive scale of the existing distributed computing solutions, the federation of small to mid-size resources will be insufficient to meet projected future demands. This paper is a case study of how the ATLAS experiment has embraced Titan---a DOE leadership facility in conjunction with traditional distributed high- throughput computing to reach sustained production scales of approximately 52M core-hours a years. The three main contributions of this paper are: (i) a critical evaluation of design and operational considerations to support the sustained, scalable and production usage of Titan; (ii) a preliminary characterization of a next generation executor for PanDA to support new workloads and advanced execution modes; and (iii) early lessons for how current and future experimental and observational systems can be integrated with production supercomputers and other platforms in a general and extensible manner

    Discovery and Characterization of Transiting SuperEarths Using an All-Sky Transit Survey and Follow-up by the James Webb Space Telescope

    Get PDF
    Doppler and transit surveys are finding extrasolar planets of ever smaller mass and radius, and are now sampling the domain of superEarths (1-3 Earth radii). Recent results from the Doppler surveys suggest that discovery of a transiting superEarth in the habitable zone of a lower main sequence star may be possible. We evaluate the prospects for an all-sky transit survey targeted to the brightest stars, that would find the most favorable cases for photometric and spectroscopic characterization using the James Webb Space Telescope (JWST). We use the proposed Transiting Exoplanet Survey Satellite (TESS) as representative of an all-sky survey. We couple the simulated TESS yield to a sensitivity model for the MIRI and NIRSpec instruments on JWST. We focus on the TESS planets with radii between Earth and Neptune. Our simulations consider secondary eclipse filter photometry using JWST/MIRI, comparing the 11- and 15-micron bands to measure CO2 absorption in superEarths, as well as JWST/NIRSpec spectroscopy of water absorption from 1.7-3.0 microns, and CO2 absorption at 4.3-microns. We project that TESS will discover about eight nearby habitable transiting superEarths. The principal sources of uncertainty in the prospects for JWST characterization of habitable superEarths are superEarth frequency and the nature of superEarth atmospheres. Based on our estimates of these uncertainties, we project that JWST will be able to measure the temperature, and identify molecular absorptions (water, CO2) in one to four nearby habitable TESS superEarths.Comment: accepted for PASP; added discussion and figure for habitable planets; abridged Abstrac
    • …
    corecore