2,236 research outputs found

    Ground Risk Assessment Service Provider (GRASP) Development Effort as a Supplemental Data Service Provider (SDSP) for Urban Unmanned Aircraft System (UAS) Operations

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    NASAs Unmanned Aircraft System (UAS) Traffic Management (UTM) project aims to enable the integration of new aviation paradigms such as Unmanned Aircraft Systems (UAS) while providing the necessary infrastructure for future concepts such as On-Demand Mobility (ODM) and Urban Air Mobility (UAM) operations in the National Airspace System (NAS). In order to do so, the UTM project has developed an architecture to allow communication among UAS operators, UAS Service Suppliers (USS), Air Navigation Service Providers (ANSP), and the public. As part of this framework, the Supplemental Data Service Providers (SDSP) are envisioned as model and/or data based services that disseminate essential or enhanced information to ensure safe operations within low-altitude airspace. These services include terrain and obstacle data, specialized weather data, surveillance, constraint information, risk monitoring, etc. This paper highlights the development efforts of a non-participant casualty risk assessment SDSP called Ground Risk Assessment Service Provider (GRASP) which assists operators with preflight planning. GRASP is based on the previously introduced UTM Risk Assessment Framework (URAF) and allows UAS operators to simulate and visualize potential non-participant casualty risks associated with their proposed flight. The risk assessment capability also allows operators to revise their flight plans if the casualty risks are determined to be above acceptable thresholds. GRASP is configured to account for future improvements including servicing airborne aircraft as part of NASAs System-Wide Safety (SWS) project

    Architectural Urbanism: Melbourne/Seoul

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    Architectural Urbanism is an ambition and sensibility for propositions that address the context of the city within the operative scale of the small architectural project. Architectural urbanism represents a tailoring of projects to the local; to the materiality and specificity of the everyday; and to the grain and substance of the location above all else. Architectural urbanism is less about erasure and more about insertion; infill; the weaving of old and new and the dynamics that evolve from subtle and careful manipulation of the city in detail. The exhibition explores commonality in the apparently different contexts of both cities – speculating on these as forms of ‘architectural urbanism' in the contemporary city of the Asia-Pacific at its northern and southern extremes. Architectural projects from five Melbourne architectural practitioners have been selected to exhibit in Seoul. The practices are: Muir Mendes, Baracco + Wright, Iredale Pederson Hook, NMBW Architecture Studio and Kerstin Thompson Architects - all of whom have strong links to the RMIT Architecture design research and teaching community. Melanie Dodd co-curated the exhibition

    New Records for \u3ci\u3eEuhrychiopsis Lecontei\u3c/i\u3e (Coleoptera: Curculionidae) and Their Densities in Wisconsin Lakes

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    The native aquatic weevil, Euhrychiopsis lecontei is currently being researched as a potential biological control for the exotic aquatic macrophyte Eurasian watermilfoil (Myriophyllum spicatum), yet little is known about its specific distribution in North America. In this study, E. lecontei was collected in 25 of 27 lakes surveyed for the weevil in Wisconsin, greatly increasing the known distribution of the species in this state. E. lecontei densities evaluated in 14 Wisconsin lakes ranged from \u3c0.01 to 1.91 weevils per apical stem of milfoil. These new records indicate that E. lecontei is widespread throughout Wisconsin and is associated with natural declines of M. spicatum in some lakes. Additional sampling for E. lecontei and research on its ecology and life history are needed to understand the role of this organism in aquatic ecosystems

    Temporal and spatial changes in milfoil distribution and biomass associated with weevils in Fish Lake, WI

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    During the course of an eight year monitoring effort, the Wisconsin Department of Natural Resources documented a significant decline in milfoil biomass and distribution in Fish Lake, Wisconsin. Average milfoil biomass declined by 40- 50% from 374-524 g dw m -2 during 1991-93 to 265 g dw m -2 during both 1994 and 1995. Milfoil recovered fully in 1996- 98 to 446- 564 g dw m -2 . The size of the milfoil bed, as discerned from aerial photographs, shrank from a maximum coverage of 40 ha in 1991 to less than 20 ha during 1995. During the “crash” of 1994-95, milfoil plants exhibited typical signs of weevil-induced damage, including darkened, brittle, hollowed-out growing tips, and the arching and collapse of stems associated with loss of buoyancy. Monitoring of weevils and stem damage during 1995-98 showed highest densities and heaviest damage occurred near shore and subsequently fanned out into deeper water from core infestation sites each spring. The extent of milfoil stem damage was positively correlated with weevil densities (monthly sampling). However, weevil densities and stem damage were lower during 1995 (when milfoil biomass was in decline) than during 1996-98 (when milfoil biomass was fully recovered)

    Euhrychiopsis lecontei distribution, abundance, and experimental augmentations for Eurasian watermilfoil control in Wisconsin lakes

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    The specialist aquatic herbivore Euhrychiopsis lecontei (Dietz) is currently being researched as a potential biological control agent for Eurasian watermilfoil (Myriophyllum spicatum L.). Our research in Wisconsin focused on 1) determining milfoil weevil distribution across lakes, 2) assessing limnological characteristics associated with their abundance, and 3) evaluating milfoil weevil augmentation as a practical management tool for controlling Eurasian watermilfoil

    The Value of Water Quality Information for National Environmental Regulation

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    Soybean harvest aids (1993)

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    Except when they have large stems, dead weeds usually cause only minor harvest problems. But unfortunately, only a hard frost will stop the growth and dry up some weeds. However, the average date of the first hard frost in most parts of Missouri is relatively late compared to the average date of soybean maturity and harvest (Figures 1 and 2). Delaying harvest until after a hard frost could result in shattering losses, further delays due to wet weather, delayed wheat planting, and delayed fall tillage. Weed problems could also be more serious in following years because of the extra time weed seeds have to reach maturity

    Ice Age Epochs and the Sun's Path Through the Galaxy

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    We present a calculation of the Sun's motion through the Milky Way Galaxy over the last 500 million years. The integration is based upon estimates of the Sun's current position and speed from measurements with Hipparcos and upon a realistic model for the Galactic gravitational potential. We estimate the times of the Sun's past spiral arm crossings for a range in assumed values of the spiral pattern angular speed. We find that for a difference between the mean solar and pattern speed of Omega_Sun - Omega_p = 11.9 +/- 0.7 km/s/kpc the Sun has traversed four spiral arms at times that appear to correspond well with long duration cold periods on Earth. This supports the idea that extended exposure to the higher cosmic ray flux associated with spiral arms can lead to increased cloud cover and long ice age epochs on Earth.Comment: 14 pages, 3 figures, accepted for publication in Ap

    Soybean variety selection (1993)

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    One of the most perplexing production decisions a farmer faces is, 'What variety should I plant?' Information on soybean varieties is received from mass media advertising, friends or relatives, seed dealers, University and extension variety trials, and perhaps from your own strip trials. New varieties from public and private organizations are abundant. Yields are increasing about one-third of a bushel per acre per year due to genetic improvement. While some new varieties show this response, other new varieties may not yield better than those now used. Given all this information and the new influx of varieties, how do you choose the best variety to grow? No one has yet developed a simple answer to this question, but it is the intent of this publication to present guidelines for choosing a variety for a given set of conditions
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