1,087 research outputs found

    Communication Platform Payload Definition (CPPD) study. Volume 3: Addendum

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    This is Volume 3 (Addendum) of the Ford Aerospace & Communications Corporation Final Report for the Communication Platform Payload Definition (CPPD) Study Program conducted for NASA Lewis Research Center under contract No. NAS3-24235. This report presents the results of the study effort leading to five potential platform payloads to service CONUS and WARC Region 2 traffic demand as projected to the year 2008. The report addresses establishing the data bases, developing service aggregation scenarios, selecting and developing 5 payload concepts, performing detailed definition of the 5 payloads, costing them, identifying critical technology, and finally comparing the payloads with each other and also with non-aggregated equivalent services

    The Effects of Vertically-Oriented Resistance Training on Golf Swing Performance Variables

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    The purpose of this study was to examine the effects of vertically-oriented resistance training on golf driving performance. Ten Division-I collegiate golfers completed 2 resistance training sessions per week for 10 weeks during the fall tournament season. Pre- and posttraining assessments of strength-power and golf performance were compared. To assess strength-power, jump height, peak force, and peak power (PP) were measured from static and countermovement (CMJ) vertical jumps; peak force and rate of force development from 0-250 ms were measured from an isometric mid-thigh pull. Golf performance was assessed in terms of ball launch speed (BS), spin rate, carry yardage (CY), and total yardage (TY), averaged from 5 shots using a driver. Following training, all measures of strength-power improved, with CMJ PP improving significantly (p\u3c0.00625). The golf performance assessment indicated significant increases (p\u3c0.0125) in BS, CY, and TY. These results suggest that vertically-oriented resistance training can improve golf driving performance

    Study of aerodynamic technology for single-cruise engine V/STOL fighter/attack aircraft

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    A conceptual design analysis is performed on a single engine V/STOL supersonic fighter/attack concept powered by a series flow tandem fan propulsion system. Forward and aft mounted fans have independent flow paths for V/STOL operation and series flow in high speed flight. Mission, combat and V/STOL performance is calculated. Detailed aerodynamic estimates are made and aerodynamic uncertainties associated with the configuration and estimation methods identified. A wind tunnel research program is developed to resolve principal uncertainties and establish a data base for the baseline configuration and parametric variations

    Communication Platform Payload Definition (CPPD) study. Volume 2: Technical report

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    This is Volume 2 (Technical Report) of the Ford Aerospace & Communications Corporation Final Report for the Communication Platform Payload Definition (CPPD) Study program conducted for NASA Lewis Research Center under contract No. NAS3-24235. This report presents the results of the study effort leading to five potential platform payloads to service CONUS and WARC Region 2 traffic demand as projected to the year 2008. The report addresses establishing the data bases, developing service aggregation scenarios, selecting and developing 5 payload concepts, performing detailed definition of the 5 payloads, costing them, identifying critical technology, and finally comparing the payloads with each other and also with non-aggregated equivalent services

    Silicon web process development

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    A barrier crucible design which consistently maintains melt stability over long periods of time was successfully tested and used in long growth runs. The pellet feeder for melt replenishment was operated continuously for growth runs of up to 17 hours. The liquid level sensor comprising a laser/sensor system was operated, performed well, and meets the requirements for maintaining liquid level height during growth and melt replenishment. An automated feedback loop connecting the feed mechanism and the liquid level sensing system was designed and constructed and operated successfully for 3.5 hours demonstrating the feasibility of semi-automated dendritic web growth. The sensitivity of the cost of sheet, to variations in capital equipment cost and recycling dendrites was calculated and it was shown that these factors have relatively little impact on sheet cost. Dendrites from web which had gone all the way through the solar cell fabrication process, when melted and grown into web, produce crystals which show no degradation in cell efficiency. Material quality remains high and cells made from web grown at the start, during, and the end of a run from a replenished melt show comparable efficiencies

    First Record of a Nurse Shark, Ginglymostoma cirratum, within the Mississippi Sound

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    Of all the coastal shark species in the northern Gulf of Mexico, the nurse shark, Ginglymostoma cirratum, is one of the few species not documented in the Sound. Unlike most coastal sharks, nurse shark distribution is confined to a relatively specific suite of abiotic characteristics. Hannan et al. (2012) demonstrated that the distribution of nurse sharks in the northern GOM is primarily limited to hard bottom habitats with relatively high temperature, salinity, dissolved oxygen, and water clarity. Herein, we provide support for the findings of Hannan et al. (2012) and report the first documented occurrence of a nurse shark in the Sound

    Diel Vertical Movements of a Scalloped Hammerhead, \u3ci\u3eSphyrna lewini\u3c/i\u3e, in the Northern Gulf of Mexico

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    Despite the circumglobal distribution of scalloped hammerheads, Sphyrna lewini (Griffith and Smith, 1834), little information is available regarding fine-scale movement and habitat use patterns for this species. Over a 27-d period, data were collected on diel habitat use and environmental preferences of a 240 cm (total length) female S. lewini. The shark exhibited a consistent and repeated diel vertical movement pattern, making more than 76 deep nighttime dives; the maximum depth reached was 964 m, where the temperature was 5.8 degrees C. The purpose of the nightly oscillatory deep diving pattern is unknown but could possibly represent feeding behavior. These findings represent the first detailed account of S. lewini diel vertical behavior and habitat utilization in the western North Atlantic Ocean

    GAM: a web-service for integrated transcriptional and metabolic network analysis

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    Novel techniques for high-throughput steady-state metabolomic profiling yield information about changes of nearly thousands of metabolites. Such metabolomic profiles, when analyzed together with transcriptional profiles, can reveal novel insights about underlying biological processes. While a number of conceptual approaches have been developed for data integration, easily accessible tools for integrated analysis of mammalian steady-state metabolomic and transcriptional data are lacking. Here we present GAM (‘genes and metabolites’): a web-service for integrated network analysis of transcriptional and steady-state metabolomic data focused on identification of the most changing metabolic subnetworks between two conditions of interest. In the web-service, we have pre-assembled metabolic networks for humans, mice, Arabidopsis and yeast and adapted exact solvers for an optimal subgraph search to work in the context of these metabolic networks. The output is the most regulated metabolic subnetwork of size controlled by false discovery rate parameters. The subnetworks are then visualized online and also can be downloaded in Cytoscape format for subsequent processing. The web-service is available at: https://artyomovlab.wustl.edu/shiny/gam

    Observations of a Feeding Aggregation of Whale Sharks, Rhincodon typus, in the North Central Gulf of Mexico

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    On 26 June 2006 an aggregation of 16 whale sharks was observed for a period of 4 hr in the north central Gulf of Mexico (GOM). The sharks remained within an area about 1.0 km2 in size and continuously ram filter fed at the surface. Visual analysis of a plankton sample collected from the study site revealed the presence of copious amounts of fish eggs in mid-embryonic development and a minor amount of other zooplankton. A second plankton sample (control) collected about 3.5 km from the study site in an area where no whale sharks were present contained few eggs, however other zooplankton were similar to the study site sample in species composition and abundance. Two egg morphs were identified, and samples of one of the morphs, which represented 98% of the eggs at the study site, were verified by genetic analysis as little tunny, Euthynnus alleteratus. The observed feeding behavior and the abundance of fish eggs at the study site indicated the whale sharks were feeding on recently spawned little tunny eggs. This represents the first confirmed observation of a feeding aggregation of whale sharks in the GOM

    First Record of a Sleeper Shark in the Western Gulf of Mexico and Comments on Taxonomic Uncertainty Within Somniosus (Somniosus)

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    A sleeper shark, Somniosus (Somniosus) sp., is reported from Alaminos Canyon in the western Gulf of Mexico at a depth of about 2647 m based on observations made using a remotely operated vehicle. This is the first record of a sleeper shark (Somniosus, Somniosidae) from the western Gulf of Mexico and deepest record of any shark from the Gulf of Mexico. Despite claims to the contrary in the literature, no taxonomic character has been identified to date that can be used to unequivocally identify all representatives of Somniosus (Somniosus), and as a result, some species records must be considered dubious
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