609 research outputs found

    The politics of the 1987 Iowa groundwater protection act

    Get PDF
    http://www.worldcat.org/oclc/2240033

    Comparing Experiments to the Fault-Tolerance Threshold

    Full text link
    Achieving error rates that meet or exceed the fault-tolerance threshold is a central goal for quantum computing experiments, and measuring these error rates using randomized benchmarking is now routine. However, direct comparison between measured error rates and thresholds is complicated by the fact that benchmarking estimates average error rates while thresholds reflect worst-case behavior when a gate is used as part of a large computation. These two measures of error can differ by orders of magnitude in the regime of interest. Here we facilitate comparison between the experimentally accessible average error rates and the worst-case quantities that arise in current threshold theorems by deriving relations between the two for a variety of physical noise sources. Our results indicate that it is coherent errors that lead to an enormous mismatch between average and worst case, and we quantify how well these errors must be controlled to ensure fair comparison between average error probabilities and fault-tolerance thresholds.Comment: 5 pages, 2 figures, 13 page appendi

    Toric codes and quantum doubles from two-body Hamiltonians

    Get PDF
    We present here a procedure to obtain the Hamiltonians of the toric code and Kitaev quantum double models as the low-energy limits of entirely two-body Hamiltonians. Our construction makes use of a new type of perturbation gadget based on error-detecting subsystem codes. The procedure is motivated by a projected entangled pair states (PEPS) description of the target models, and reproduces the target models' behavior using only couplings that are natural in terms of the original Hamiltonians. This allows our construction to capture the symmetries of the target models

    The U.S. household furniture industry: Adapting to changing times.

    Get PDF
    The U.S. wood household furniture industry has adapted to change in many ways in recent years. The industry has grown steadily since the 1982 recession, and has been shifting to the U.S . South and Southeast. Although California has also become prominent in furniture production, many recent factors indicate geographic shifts away from the state, particularly in wood furniture production. The household furniture industry has also adapted and continues to adapt to factors which have increased the globalization of trade in all products. Foreign competition has resulted in mergers and consolidation in the U.S. household furniture industry, and has also forced production to become more oriented toward non ready-to-assemble and upholstered furniture

    Distribution and incidence of viruses in Irish seed potato crops

    Get PDF
    peer-reviewedVirus diseases are of key importance in potato production and in particular for the production of disease-free potato seed. However, there is little known about the frequency and distribution of potato virus diseases in Ireland. Despite a large number of samples being tested each year, the data has never been collated either within or across years. Information from all known potato virus testing carried out in the years 2006–2012 by the Department of Agriculture Food and Marine was collated to give an indication of the distribution and incidence of potato virus in Ireland. It was found that there was significant variation between regions, varieties, years and seed classes. A definition of daily weather data suitable for aphid flight was developed, which accounted for a significant proportion of the variation in virus incidence between years. This use of weather data to predict virus risk could be developed to form the basis of an integrated pest management approach for aphid control in Irish potato crops

    The Mississippi furniture industry and its use of wood-based materials

    Get PDF
    Furniture manufacturing is one of the most important industries in Mississippi; the industry\u27s phenomenal growth and current high levels of production and employment have recently been widely recognized and publicized. The Mississippi Economic Council (1988), for example, recently labeled the state The New Furniture Capital of America;\u27 and Northeast Mississippi was recently described as a booming region\u27\u27 that wants to be the Furniture Capital of America\u27\u27 (Evans 1987). The present report characterizes important aspects of Mississippi\u27s furniture industry, including its development and relative importance within the state and within the U.S., and assesses current information on the availability and use of wood-based raw materials. The report has major sections on The Mississippi Furniture Industry and Use of Wood-Based Materials, with a Discussion section summarizing the current outlook for furniture production and demand
    corecore