144,528 research outputs found

    Forcing of Climate Variations by Mev-gev Particles

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    Changes in ionization production in the lower stratosphere by a few percent during Forbush decreases have been shown to correlate well with changes in winter tropospheric dynamics by a similar relatively small amount. Changes in ionization production by tens of percent on the decadal time scale have been shown to be correlated with changes in winter storm frequencies by tens of percent in the western North Atlantic. Changes in total solar irradiance or solar UV do not have time variations to match the tropospheric variations on the day to day time scales discussed here. Forcing related to magnetic activity is not supported. Thus solar wind/MeV-GeV particle changes appear to be the only viable forcing function for these day to day variations. If solar wind/particle forcing of a few percent amplitude can produce short term weather responses, then observed changes by tens of percent on the decadal and centennial time scale could produce climate changes on these longer time scales. The changes in circulation involved would produce regional climate changes, as observed. At present the relations between stratospheric ionization, electric fields and chemistry and aerosol and cloud microphysics are as poorly known as the relations between the latter and storm feedback processes. However, the capability for investigating these relationships now exists and has recently been most successfully used for elucidating the stratospheric chemistry and cloud microphysics associated with the Antarctic ozone hole. The economic benefits of being able to predict winter severity on an interannual basis, and the extent to which climate change related to solar variability will add to or substract from the greenhouse effect, should be more than adequate to justify support for research in this area

    Sorafenib for advanced and refractory desmoid tumors

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    Identifying the inflaton with primordial gravitational waves

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    We explore the ability of experimental physics to uncover the underlying structure of the gravitational Lagrangian describing inflation. While the observable degeneracy of the inflationary parameter space is large, future measurements of observables beyond the adiabatic and tensor two-point functions, such as non-Gaussianity or isocurvature modes, might reduce this degeneracy. We show that even in the absence of such observables, the range of possible inflaton potentials can be reduced with a precision measurement of the tensor spectral index, as might be possible with a direct detection of primordial gravitational waves.Comment: 5 pages, 2 figures, version to appear in PR

    Commercial aerospace: risks and prospects

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    Aerospace industries

    Stanford/NASA-Ames Center of Excellence in model-based human performance

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    The human operator plays a critical role in many aeronautic and astronautic missions. The Stanford/NASA-Ames Center of Excellence in Model-Based Human Performance (COE) was initiated in 1985 to further our understanding of the performance capabilities and performance limits of the human component of aeronautic and astronautic projects. Support from the COE is devoted to those areas of experimental and theoretical work designed to summarize and explain human performance by developing computable performance models. The ultimate goal is to make these computable models available to other scientists for use in design and evaluation of aeronautic and astronautic instrumentation. Within vision science, two topics have received particular attention. First, researchers did extensive work analyzing the human ability to recognize object color relatively independent of the spectral power distribution of the ambient lighting (color constancy). The COE has supported a number of research papers in this area, as well as the development of a substantial data base of surface reflectance functions, ambient illumination functions, and an associated software package for rendering and analyzing image data with respect to these spectral functions. Second, the COE supported new empirical studies on the problem of selecting colors for visual display equipment to enhance human performance in discrimination and recognition tasks

    Bibliography of research using the NZIER’s quarterly survey of business opinion

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    The New Zealand Institute of Economic Research (NZIER) has conducted and published a quarterly survey of business opinion continuously, and with largely unchanged questions, since June 1961. The Institute’s Quarterly Survey of Business Opinion (QSBO) is a business tendency survey based substantially on the Business Test of the IFO Munich. It covers the manufacturing, building, merchant and service sectors and architects. This bibliography lists and classifies some 80 research papers which used QSBO data and published between 1964 and 2011

    Introduction: Finding common ground beyond fragmentation

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    This chapter begins with an outline of the European context within which the twenty six research papers presented in this book emerged. A particularly important aspect of this context is Network 27 on Didactics, Learning and Teaching of the European Educational Research Association (EERA) which formed the core of the research community in which this work was developed over a five year period (2006-11). The next part of the chapter provides an overview of the six sections which make up the structure of the book as a whole. A discussion then follows of the clear continental divide with respect to didactics, learning and teaching in the European landscape which is based on the references used by the contributors to this book. This leads to a consideration of the historical origin of present-day didactics which can be traced back to a common heritage in the work of Jan Amos Comenius (1592-1670) in order to provide a platform in the search for common ground. In the section which then follows there is a discussion of the didactic triad as a tool for holding the complexity of teaching-studying-learning situations and this is considered in an expanded context in which classroom interaction in the school is placed within a wider societal context. Based on a review of the contributions to this book, the final parts of this chapter consider existing knowledge gaps between different national traditions and also identify themes that form the basis for building and extending common ground. The themes that have been identified through this process of synthesis relate to pedagogical content knowledge, learner knowledge, joint didactical action, curriculum research, the so called shift from teaching to learning, the philosophy of Bildung and its practical implications, links between theory and practice and the significant role of experimental schools. Finally these themes are proposed for consideration within the wider research, policy and practice community as the basis for future international co-operation that offer the potential to advance mutual understanding and common insights in this fiel
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