51,898 research outputs found

    Quantitative analysis of flare accelerated electrons through their hard X-ray and microwave radiation

    Get PDF
    Hard X-ray and microwave modelling that takes into account the temporal evolution of the electron spectrum as well as the inhomogeneity of the magnetic field and the ambient medium in the radio source is presented. This method is illustrated for the June 29 1980 10:41 UT event. The implication on the process of acceleration/injection is discussed

    Solar Energetic Particle Events in the 23rd Solar Cycle: Interplanetary Magnetic Field Configuration and Statistical Relationship with Flares and CMEs

    Full text link
    We study the influence of the large-scale interplanetary magnetic field configuration on the solar energetic particles (SEPs) as detected at different satellites near Earth and on the correlation of their peak intensities with the parent solar activity. We selected SEP events associated with X and M-class flares at western longitudes, in order to ensure good magnetic connection to Earth. These events were classified into two categories according to the global interplanetary magnetic field (IMF) configuration present during the SEP propagation to 1AU: standard solar wind or interplanetary coronal mass ejections (ICMEs). Our analysis shows that around 20% of all particle events are detected when the spacecraft is immersed in an ICME. The correlation of the peak particle intensity with the projected speed of the SEP-associated coronal mass ejection is similar in the two IMF categories of proton and electron events, ≈0.6\approx 0.6. The SEP events within ICMEs show stronger correlation between the peak proton intensity and the soft X-ray flux of the associated solar flare, with correlation coefficient r= r=\,0.67±\pm0.13, compared to the SEP events propagating in the standard solar wind, r= r=\,0.36±\pm0.13. The difference is more pronounced for near-relativistic electrons. The main reason for the different correlation behavior seems to be the larger spread of the flare longitude in the SEP sample detected in the solar wind as compared to SEP events within ICMEs. We discuss to which extent observational bias, different physical processes (particle injection, transport, etc.), and the IMF configuration can influence the relationship between SEPs and coronal activity.Comment: http://adsabs.harvard.edu.ezproxy.obspm.fr/abs/2013SoPh..282..579

    Choosing Prevention Products: Questions to Ask When Considering Sexual and Relationship Violence and Stalking Prevention Products

    Get PDF
    The purpose of this white paper is to provide guidance to university and college leaders on how to choose products that address concerns of sexual and relationship violence and stalking from the perspective of prevention

    Measuring collaborative emergent behavior in multi-agent reinforcement learning

    Full text link
    Multi-agent reinforcement learning (RL) has important implications for the future of human-agent teaming. We show that improved performance with multi-agent RL is not a guarantee of the collaborative behavior thought to be important for solving multi-agent tasks. To address this, we present a novel approach for quantitatively assessing collaboration in continuous spatial tasks with multi-agent RL. Such a metric is useful for measuring collaboration between computational agents and may serve as a training signal for collaboration in future RL paradigms involving humans.Comment: 1st International Conference on Human Systems Engineering and Design, 6 pages, 2 figures, 1 tabl

    The Clustering of Organizational Innovation: Developing Governance Models for Vertical Integration

    Get PDF
    This case explores a cluster of firms that emerged sharing a particular ownership structure. Typically, clusters are thought of as interrelated firms that produce similar products and services. However, we document the emergence and evolution of a cluster of entrepreneurial ventures that developed using a unique governance structure. We explore the deviant case of Renville, MN because of its notable success in developing a series of entrepreneurial ventures that provided producers with the opportunity to vertically integrate.collective entrepreneurship, organizational innovation, joint vertical innovation, cluster, Agribusiness, Research and Development/Tech Change/Emerging Technologies, Q10, Q13, Q16,

    Analytical design and simulation evaluation of an approach flight director system for a jet STOL aircraft

    Get PDF
    A program was undertaken to develop design criteria and operational procedures for STOL transport aircraft. As part of that program, a series of flight tests shall be performed in an Augmentor Wing Jet STOL Aircraft. In preparation for the flight test programs, an analytical study was conducted to gain an understanding of the characteristics of the vehicle for manual control, to assess the relative merits of the variety of manual control techniques available with attitude and thrust vector controllers, and to determine what improvements can be made over manual control of the bare airframe by providing the pilot with suitable command guidance information and by augmentation of the bare airframe dynamics. The objective of the study is to apply closed-loop pilot/vehicle analysis techniques to the analysis of manual flight control of powered-lift STOL aircraft in the landing approach and to the design and experimental verification of an advanced flight director display

    Photoproduction of Quarkonium in Proton-Proton and Nucleus-Nucleus Collisions

    Full text link
    We discuss the photoproduction of Υ\Upsilon and J/ψJ/\psi at high energy pˉp\bar{p}p, pppp and heavy ion colliders. We predict large rates in pˉp\bar{p}p interactions at the Fermilab Tevatron %and in heavy-ion interactions at the CERN LHC. These reactions can be and in pppp and heavy-ion interactions at the CERN LHC. The J/ψJ/\psi is also produced copiously at RHIC. These reactions can be used to study the gluon distribution in protons and heavy nuclei. We also show that the different CP symmetries of the initial states lead to large differences in the transverse momentum spectra of mesonsComment: 4 pgs. with 3 figure

    Clusters and Fluctuations at Mean-Field Critical Points and Spinodals

    Full text link
    We show that the structure of the fluctuations close to spinodals and mean-field critical points is qualitatively different than the structure close to non-mean-field critical points. This difference has important implications for many areas including the formation of glasses in supercooled liquids. In particular, the divergence of the measured static structure function in near-mean-field systems close to the glass transition is suppressed relative to the mean-field prediction in systems for which a spatial symmetry is broken.Comment: 5 pages, 1 figur
    • …
    corecore