8,988 research outputs found

    Jovian equatorial H2 emission from 1979-1987

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    Ninety two IUE observations of the Jovian equatorial region taken between 2 Dec. 1978 and 1 Feb. 1988 were averaged together by date of observation, resulting in 22 averaged spectra which were fit with a model to determine the amount of H2 Lyman band emission in the region 1552 to 1624A. The data suggest that the H2 emission may vary with time. Especially suggestive is the marked downward trend of the emission between 1983 and 1987, during which time the strength of the emission in the 1552 to 1624A region decreases by a factor of 10. Uncertainty in the existing data and a gap in the data in 1980 and 1981 preclude a positive identification of a correlation between the brightness of the H2 emission and the major solar cycle

    Comparison of GEOS-5 AGCM Planetary Boundary Layer Depths Computed with Various Definitions

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    Accurate models of planetary boundary layer (PBL) processes are important for forecasting weather and climate. The present study compares seven methods of calculating PBL depth in the GEOS-5 atmospheric general circulation model (AGCM) over land. These methods depend on the eddy diffusion coefficients, bulk and local Richardson numbers, and the turbulent kinetic energy. The computed PBL depths are aggregated to the Koppen climate classes, and some limited comparisons are made using radiosonde profiles. Most methods produce similar midday PBL depths, although in the warm, moist climate classes, the bulk Richardson number method gives midday results that are lower than those given by the eddy diffusion coefficient methods. Additional analysis revealed that methods sensitive to turbulence driven by radiative cooling produce greater PBL depths, this effect being most significant during the evening transition. Nocturnal PBLs based on Richardson number are generally shallower than eddy diffusion coefficient based estimates. The bulk Richardson number estimate is recommended as the PBL height to inform the choice of the turbulent length scale, based on the similarity to other methods during the day, and the improved nighttime behavior

    Criminal sentencing by preferred numbers

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    Criminal sentencing is a complex cognitive activity often performed by the unaided mind under suboptimal conditions. As such, sentencers may not behave according to policy, guidelines and training. We analyzed the distribution of sentences meted out in one year in two different jurisdictions (i.e., England and Wales, and New South Wales, Australia). We reveal that sentencers prefer certain numbers when meting out sentence lengths (in custody and community service) and amounts (for fines/compensation). These ‘common doses’ accounted for over 90% of sentences in each jurisdiction. The size of these doses increased as sentences became more severe, and doses followed a logarithmic pattern. These findings are compatible with psychological research on preferred numbers and are reminiscent of Weber’s and Fechner’s laws. Our findings run contrary to arguments against efforts to reduce judicial discretion, and potentially undermine the notion of individualized justice, as well as raise questions about the (cost) effectiveness of sentencing

    Developing interventions to address sexuality after stroke: Findings from a four-panel modified delphi study

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    © 2019 Foundation of Rehabilitation Information. Background: Although stroke has a profound impact on sexuality there are limited evidence-based interventions to support rehabilitation professionals in this area. The aim of the current research was to prioritize content areas and approaches to sexual rehabilitation from the perspective of stroke survivors, their partners, stroke rehabilitation clinicians and researchers. Methods: A 2-step online Delphi method was used to prioritize the content of, and approaches to, sexual rehabilitation with stroke survivors, their partners, stroke rehabilitation clinicians and researchers. Results: Stroke survivors (n=30), their partners (n=18), clinicians and researchers in stroke rehabilitation (n=45) completed at least 1 of 2 investigator-developed surveys. Participants prioritized 18 core content areas for inclusion in sexual rehabilitation following stroke with a high degree of consensus. Another 27 content areas were considered moderately important. There was strong consensus that sexual rehabilitation should be offered in the subacute and chronic phases of stroke recovery. Participants would prefer health professionals to deliver the intervention face-to-face. Conclusion: This study presents opinions from stroke survivors, partners of stroke survivors, clinicians and researchers. The information about content, timing and mode of delivery will be used to develop and evaluate a comprehensive sexuality rehabilitation programme

    Mobile target tracking using a reconfigurable low earth orbit constellation

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    Traditional Earth-observing satellite constellations must preselect orbits to match established mission objectives, inherently limiting the capability of the system to respond to dynamic events. A more flexible approach to constellation design which maneuvers satellites to new orbits throughout the mission lifetime can enable the tracking of mobile targets; such a concept will be explored and evaluated in the following paper. Currently, an existing approach for creating a reconfigurable constellation of satellites (ReCon) demonstrates some increased functionality. However, the repeating ground track (RGT) orbits used are only well-suited for static ground targets (i.e. particular latitude and longitude points) as they are defined by their repetitious passes over the particular points on the globe; inherently these orbits are not ideal for tracking mobile targets such as ships, oil spills, hurricanes, and other weather events. By addressing this gap and designing the constellation to follow these mobile targets, data return can be of higher quality and quantity leading toward improved predictions of future movements. Traditional non-maneuverable satellites may of course capture mobile feature data; however, the quality and quantity of data returned is driven by the satellites’ orbits which were not designed for the particular mobile target. A proposed concept of operations that models possible sequential satellite maneuvers as a graph has shown promise for tracking mobile targets in the case of a single satellite. In the following paper, this concept is further explored by the addition of an optimizer to this method, applied to both a single satellite and a constellation of maneuverable satellites, like ReCon. Results for a tropical storm case study indicate that with relatively low amounts of delta-V per satellite, many possible maneuver combinations are found which result in improved accesses with greater total access time and closer passes. Trade-offs are shown between total target access time, mean distance to targets upon access, and total delta-V used. The performance of increased constellation size is also explored. By having satellites dynamically respond to mobile targets such as hurricanes, satellite imagery and remote sensing can be of better quality and even contribute to better predictions for developing storms

    Seasonal Distributions and Movements of Longnose Gar (Lepisosteus osseus) within the York River System, Virginia

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    The seasonal movements of Lepisosteus osseus (Longnose Gar) are largely unknown. The goal of this project was to characterize spawning movements and seasonal distributions by using acoustic tagging methods and examining historical catch records from a trawl survey. This is the first time that movements have been studied for an estuarine population of Longnose Gar. Two individuals moved greater minimum distances (69 and 74 km) than found in the only other report on movement in this species. Spawning-ground residency time, collected from two tagged Longnose Gar, was approximately one month, and tidal periodicity was observed for one of the two fish. Data from a fisheries independent trawl survey were used to examine seasonal catch distributions in Longnose Gar and represents the first report of winter distributions for this species. Winter locations occurred both alongshore and mid-channel, and the distributions were similar to those in the summer and fal

    Pseudomorphic Growth of a Single Element Quasiperiodic Ultrathin Film on a Quasicrystal Substrate

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    An ultrathin film with a periodic interlayer spacing was grown by the deposition of Cu atoms on thefivefold surface of the icosahedral Al70 Pd21 Mn9 quasicrystal. For coverages from 5 to 25 monolayers, a distinctive quasiperiodic low-energy electron diffraction pattern is observed. Scanning tunneling microscopy images show that the in-plane structure comprises rows having separations of S = 4.5 ïżœ0.2 ïżœA and L = 7.3 0.3 A, whose ratio equals ïżœ =1.618... within experimental error. The sequences of such row separations form segments of terms of the Fibonacci sequence, indicative of the formation of a pseudomorphic Cu film
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