27,243 research outputs found

    Correlations between the proton temperature anisotropy and transverse high-frequency waves in the solar wind

    Full text link
    Correlations are studied between the power density of transverse waves having frequencies between 0.010.01 and 11 normalized to the proton gyrofrequency in the plasma frame and the ratio of the perpendicular and parallel temperature of the protons. The wave power spectrum is evaluated from high-resolution 3D magnetic field vector components, and the ion temperatures are derived from the velocity distribution functions as measured in fast solar wind during the Helios-2 primary mission at radial distances from the Sun between 0.3~AU and 0.9~AU. From our statistical analysis, we obtain a striking correlation between the increases in the proton temperature ratio and enhancements in the wave power spectrum. Near the Sun the transverse part of the wave power is often found to be by more than an order of magnitude higher than its longitudinal counterpart. Also the measured ion temperature anisotropy appears to be limited by the theoretical threshold value for the ion-cyclotron instability. This suggests that high-frequency Alfv\'{e}n-cyclotron waves regulate the proton temperature anisotropy.Comment: Some references have been adde

    Influence of bandwidth restriction on the signal-to-noise performance of a modulated PCM/NRZ signal, part 2

    Get PDF
    Analyzing effects of bandlimiting on performance of digital transmission corrupted by additive white Gaussian noise by averaging and series expansio

    Maximized string order parameters in the valence bond solid states of quantum integer spin chains

    Full text link
    We propose a set of maximized string order parameters to describe the hidden topological order in the valence bond solid states of quantum integer spin-S chains. These optimized string order parameters involve spin-twist angles corresponding to ZS+1Z_{S+1} rotations around zz or xx-axes, suggesting a hidden ZS+1×ZS+1Z_{S+1}\times Z_{S+1} symmetry. Our results also suggest that a local triplet excitation in the valence bond solid states carries a ZS+1Z_{S+1} topological charge measured by these maximized string order parameters.Comment: 5 pages, 1 figur

    Game Based Learning for Safety and Security Education

    Full text link
    Safety and security education are important part of technology related education, because of recent number of increase in safety and security related incidents. Game based learning is an emerging and rapidly advancing forms of computer-assisted instruction. Game based learning for safety and security education enables students to learn concepts and skills without the risk of physical injury and security breach. In this paper, a pedestal grinder safety game and physical security game have been developed using industrial standard modeling and game development software. The average score of the knowledge test of grinder safety game was 82%, which is higher than traditional lecture only instruction method. In addition, the survey of physical security game shows 84% average satisfaction ratio from high school students who played the game during the summer camp. The results of these studies indicated that game based learning method can enhance students' learning without potential harm to the students

    Key Findings From HSC's 2010 Site Visits: Health Care Markets Weather Economic Downturn, Brace for Health Reform

    Get PDF
    Presents findings about hospital payment rate increases, hospital-physician alignment, and insurance premiums, funding for safety-net providers, and their implications from HSC's site visits to twelve nationally representative metropolitan communities
    • …
    corecore