37,597 research outputs found

    Mask breathing system for the Apollo command module

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    Breathing mask for Apollo command module spacecre

    The shapes of the circumstellar silicate features

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    Around oxygen-rich stars the spectra of most long-period variables (LPV) show an excess infrared emission which is attributed to circumstellar silicate dust grains. It is known that the spectral energy distribution of the 10 micron emissions shows variations from star to star. With the availability of many Infrared Astronomy Satellite (IRAS) Low Resolution Spectra (LRS) in the 8 to 22 micron region, the 10 micron feature can be studied to determine its uniformity (or lack thereof). The excess silicate emissions (10 micron emission), divided into three groups characterized by similar spectral shapes, are discussed

    A New Concept for Controlled Lifting Entry Flight Experiments

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    Feasibility of trajectory guidance and control concept for lifting configuration with roll modulatio

    The impact of poor asthma control among asthma patients treated with inhaled corticosteroids plus long-acting Ī²2-agonists in the United Kingdom : a cross-sectional analysis

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    This study was sponsored by Boehringer Ingelheim Ltd UK, which was involved in all stages of the study conduct and analysis and also funded all costs associated with the development of the manuscript. The authors acknowledge Kantar Health and Errol J Philip for providing medical writing support. Editorial assistance and medical writing support was also provided by Michelle Rebello, PhD, and Suchita Nath-Sain, PhD, of Cactus Communications. This study was sponsored by Boehringer Ingelheim Ltd., UK, which also funded all costs associated with the development of the manuscript. Author Correction, npj Primary Care Respiratory Medicine 27, Article number: 65 (2017) doi:10.1038/s41533-017-0063-5, 05 December 2017 Correction to:npj Primary Care Respiratory Medicine (2017); doi:10.1038/s41533-017-0014-1; Published 09 March 2017Peer reviewedPublisher PD

    Entropic issues in contemporary cosmology

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    Penrose [1] has emphasized how the initial big bang singularity requires a special low entropy state. We address how recent brane cosmological schemes address this problem and whether they offer any apparent resolution. Pushing the start time back to t=āˆ’āˆžt=-\infty or utilizing maximally symmetric AdS spaces simply exacerbates or transfers the problem. Because the entropy of de Sitter space is Sā‰¤1/Ī›S\leq 1/\Lambda, using the present acceleration of the universe as a low energy (Ī›āˆ¼10āˆ’120(\Lambda\sim 10^{-120}) inflationary stage, as in cyclic ekpyrotic models, produces a gravitational heat death after one cycle. Only higher energy driven inflation, together with a suitable, quantum gravity holography style, restriction on {\em ab initio} degrees of freedom, gives a suitable low entropy initial state. We question the suggestion that a high energy inflationary stage could be naturally reentered by Poincare recurrence within a finite causal region of an accelerating universe. We further give a heuristic argument that so-called eternal inflation is not consistent with the 2nd law of thermodynamics within a causal patch.Comment: brief discussion on Poincare recurrence include

    Embodiment and designing learning environments

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    There is increasing recognition amongst learning sciences researchers of the critical role that the body plays in thinking and reasoning across contexts and across disciplines. This workshop brings ideas of embodied learning and embodied cognition to the design of instructional environments that engage learners in new ways of moving within, and acting upon, the physical world. Using data and artifacts from participants' research and designs as a starting point, this workshop focuses on strategies for how to effectively leverage embodiment in learning activities in both technology and non-technology environments. Methodologies for studying/assessing the body's role in learning are also addressed

    Sparse Bayesian mass-mapping with uncertainties: hypothesis testing of structure

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    A crucial aspect of mass-mapping, via weak lensing, is quantification of the uncertainty introduced during the reconstruction process. Properly accounting for these errors has been largely ignored to date. We present results from a new method that reconstructs maximum a posteriori (MAP) convergence maps by formulating an unconstrained Bayesian inference problem with Laplace-type ā„“1\ell_1-norm sparsity-promoting priors, which we solve via convex optimization. Approaching mass-mapping in this manner allows us to exploit recent developments in probability concentration theory to infer theoretically conservative uncertainties for our MAP reconstructions, without relying on assumptions of Gaussianity. For the first time these methods allow us to perform hypothesis testing of structure, from which it is possible to distinguish between physical objects and artifacts of the reconstruction. Here we present this new formalism, demonstrate the method on illustrative examples, before applying the developed formalism to two observational datasets of the Abel-520 cluster. In our Bayesian framework it is found that neither Abel-520 dataset can conclusively determine the physicality of individual local massive substructure at significant confidence. However, in both cases the recovered MAP estimators are consistent with both sets of data
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