1,733 research outputs found

    Communications systems technology assessment study. Volume 2: Results

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    The cost and technology characteristics are examined for providing special satellite services at UHF, 2.5 GHz, and 14/12 GHz. Considered are primarily health, educational, informational and emergency disaster type services. The total cost of each configuration including space segment, earth station, installation operation and maintenance was optimized to reduce the user's total annual cost and establish preferred equipment performance parameters. Technology expected to be available between now and 1985 is identified and comparisons made between selected alternatives. A key element of the study is a survey of earth station equipment updating past work in the field, providing new insight into technology, and evaluating production and test methods that can reduce costs in large production runs. Various satellite configurations were examined. The cost impact of rain attenuation at Ku-band was evaluated. The factors affecting the ultimate capacity achievable with the available orbital arc and available bandwidth were analyzed

    Mobile radio alternative systems study satellite/terrestrial (hybrid) systems concepts

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    The use of satellites for mobile radio service in non-urban areas of the United States in the years from 1985 to 2000 was investigated. Several satellite concepts are considered: a system with single-beam coverage of the fifty United States and Puerto Rico, and multi-beam satellites with greater capacity. All of the needed functions and services identified in the market study are provided by the satellite systems, including nationwide radio access to vehicles without knowledge of vehicle location wideband data transmission from remote sites, two way exchange of short data and control messages between vehicles and dispatch or control centers, and automatic vehicle location (surveillance). The costs of providing the services are within acceptable limits, and the desired returns to the system investors are attractive. The criteria by which the Federal Communication judges the competing demands for public radio spectrum are reviewed with comments on how the criteria might apply to the consideration of land mobile satellites. Institutional arrangements for operating a mobile satellite system are based on the present institutional arrangements in which the services are offered to the end users through wireline and radio common carriers, with direct access by large private and government users

    A 3D track finder for the Belle II CDC L1 trigger

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    Machine learning methods are integrated into the pipelined first level (L1) track trigger of the upgraded flavor physics experiment Belle II at KEK in Tsukuba, Japan. The novel triggering techniques cope with the severe background from events outside the small collision region provided by the new SuperKEKB asymmetric-energy electron-positron collider. Using the precise drift-time information of the central drift chamber which provides axial and stereo wire layers, a neural network L1 trigger estimates the 3D track parameters of tracks, based on input from the axial wire planes provided by a 2D track finder. An extension of this 2D Hough track finder to a 3D finder is proposed, where the single hit representations in the Hough plane are trained using Monte Carlo. This 3D finder improves the track finding efficiency by including the stereo sense wires as input. The estimated polar track angle allows a specialization of the subsequent neural networks to sectors in the polar angle

    Performance and Carcass Traits of Market Beef Cattle Supplemented Self-Fed Byproducts on Pasture: Final Report

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    Over a two year period (2007 and 2008), 162 head of beef steers were finished with self-fed byproducts on cool season grass pastures. Yearling steers were continuously grazed at the Neely-Kinyon Farm in southwest Iowa on cool season grasses that were predominantly fescue at a stocking density of 2.25 head/acre. Half of the cattle were implanted (with Synovex®-S) or half were not. Cattle received a diet of either soyhulls-dried distillers grain with solubles (DDGS) or ground corn-dried distillers grains with solubles that was offered through self-feeders. The rations were mixed at a 1:1 ratio with a mineral balancer added which included Rumensin®. Live cattle performance and carcass traits were not affected by diet. Implanted cattle outgained non-implanted over the entire finishing period (3.52 lbs/d vs. 3.17 lbs/d). This led to implanted cattle coming off test heavier (1324 lbs vs. 1277 lbs) and railing with heavier carcasses (826 lbs vs. 800 lbs). Ribeye areas were greater (13.1 in2 vs. 12.7 in2) for implanted cattle; which was probably due to the heavier carcass weights. Non-implanted cattle had superior quality grades (55% vs. 40%) of low choice or better. Fatty acid profiles from the first year were analyzed and showed that raw beef samples from cattle on the soyhulls diet had significantly higher C18:2 In conclusion, pasture rearing cattle, when given access to self-fed by-products, provides for excellent performance on both live performance and carcass traits. Some considerations should be made by the feeder in regards to time of year when marketing cattle and the cattle’s genetics. This system is an alternative to high-grain conventional beef finishing production in feedlots

    Performance and Carcass Traits of Market Beef Cattle Supplemented Self-Fed Byproducts on Pasture: A Progress Report

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    Over a two year period (2007 and 2008), 162 head of beef steers were finished with self-fed byproducts on cool season grass pastures. Yearling steers were continuously grazed at the Neely-Kinyon Farm in southwest Iowa on cool season grasses that were predominantly fescue at a stocking density of 2.25 head/acre. Half of the cattle were implanted (with Synovex®-S) or and half were not. Cattle received a diet of either soyhulls-dried distillers grain with solubles or corn-dried distillers grains with solubles (DDGS) that was offered as a meal through self-feeders. The rations were mixed in at 1:1 with a mineral balancer that included Rumensin®. Live cattle performance and carcass traits were not affected by diet. Implanted cattle outgained non-implanted over the entire finishing period (3.52 lbs/d vs. 3.17 lbs/d). This led to implanted cattle coming off test heavier (1324 lbs vs. 1277 lbs) and railing with heavier carcasses (826 lbs vs. 800 lbs). Ribeye areas were greater (13.1 in 2 vs. 12.7 in 2 ) for implanted cattle; which was probably due to the heavier carcass weights. Non-implanted cattle had superior quality grades (55% vs. 40%) of low choice or better. Year differences in quality grade (1023 vs. 985 in 2007 and 2008, respectively) were observed. This difference was attributed to factors that include genetic makeup of cattle, initial weights of cattle, time of year when cattle were harvested and grading technology. In conclusion, pasture rearing cattle, when given access to self-fed by-products, provides for excellent performance on both live performance and carcass traits. Some considerations should be made by the feeder in regards to time of year when marketing cattle and the cattle’s genetics. This system is an alternative to high-grain conventional beef finishing production in feedlots

    Circumscription of rebutia minuscula (cactaceae, cactoideae)

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    Las especies de Rebutia se distribuyen desde el noroeste de la Argentina hasta el sur de Bolivia (Cochabamba a Tarija). Cinco especies crecen en la Argentina, entre ellas la especie tipo del género: R. minuscula. La diversidad fenotípica, muy común dentro de las especies de Rebutia, ha favorecido la publicación de numerosos nombres específicos e infraespecíficos, produciendo una verdadera confusión en la nomenclatura, en la sinonimia y en los caracteres distintivos de sus especies, en particular de R. minuscula, cuya delimitación se superpone con la de R. wessneriana. El propósito de este trabajo fue reevaluar la delimitación de R. minuscula. Se analizaron las características exo-micromorfológicas de poblaciones naturales que habitan en el bosque montano superior y en pastizales de altura de las provincias de Catamarca, Tucumán, Salta y Jujuy. Los datos obtenidos se documentaron con ilustraciones y fotografías; se proporciona información de distribución geográfica, observaciones ecológicas y fenológicas. Se incluyen los sinónimos y se designan los tipos nomenclaturales para algunos de ellos. Se considera a R. wessneriana como una subespecie de R. minuscula y se propone una nueva combinación y un nuevo rango para nombrarla: Rebutia minuscula subsp. wessneriana.Species of Rebutia are distributed from northwestern Argentina to southern Bolivia (Cochabamba to Tarija). Five species grow in Argentina, including the type species of the genus: R. minuscula. The phenotypic diversity, very variable within the species of Rebutia, promoted the publication of numerous specific and infraspecific names, leading to considerable confusion in nomenclature, synonymy, and distinctive characters of its species, particularly for R. minuscula, whose delimitation overlaps with that of R. wessneriana. The aim of this work is to reevaluate the circumscription of R. minuscula. Exo-micromorphological characteristics of natural populations growing in the upper mountain forest and high-grasslands of Catamarca, Tucumán, Salta and Jujuy provinces, were analyzed. Data were documented with illustrations and photographs; information of geographic distribution is provided as well as ecological and phenological observations. Synonyms are included and the nomenclatural types for some of them are established. Rebutia wessneriana is considered as subspecies of R. minuscula and a new combination and a new rank is proposed: Rebutia minuscula subsp. wessneriana.Fil: Muruaga, Nora B.. Fundación Miguel Lillo; ArgentinaFil: Figueroa Romero, María R.. Fundación Miguel Lillo; ArgentinaFil: Kiesling, Roberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Provincia de Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Universidad Nacional de Cuyo. Instituto Argentino de Investigaciones de las Zonas Áridas; Argentin
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