2,689 research outputs found
Possible identifications of the 3.4 micrometer feature
A feature at 3.4 micrometer was first detected in Comet Halley by the IKS spectrometer on board the Vega 1 probe; and subsequently from the ground. The feature has since been reported in Comet Wilson. The presence of the feature is of considerable interest for a number of reasons. First, it may represent the detection of a new parent molecule, and when combined with data from Giotto and Vega yield new information on cometary chemistry and the early solar system composition. Secondly, it may represent a link to the interstellar medium, the feature corresponds in wavelength and shape with an interstellar feature seen in absorption in a luminous star, towards the Galactic center known as GC-IRS7. The feature in turn is thought to be related with a growing family of unidentified infrared emission features seen in stellar objects, planetary nebulae, reflection nebulae, HII regions and extra galactic sources. These features occur at wavelengths 3.3, 3.4, 3.5, 6.2, 7.7, 8.6, and 11.25 micrometers. Further identification theory is given
Operational criteria used by professional social workers to assess relationship
Thesis (M.S.)--Boston Universit
New methods for the enantiomeric excess determination using NMR
The synthesis of enantiomerically pure compounds is an important objective of the organic chemistry. Especially in the field of medicine and pesticides, mostly one enantiomer is responsible for the biological activity. Certain examples are known where the other enantiomer is more than isomerical balast, and its presence gives rise to side-effects. It is not surprising that the regulatory authorities in Europe and the United States usually impose that chiral compounds are marketed as single enantiomers. Growing interest and improvement in enantioselective synthesis leads to an increased demand for accurate, reliable and convenient methods of measuring the enantiomeric composition. A large number of methods for the determination of the enantiomeric excess (e.e.) of regardless which chiral substrate have been developed over the years. A popular, accurate, and moreover, fast method for the determination of the enantiomeric composition is to make use of NMR techniques (Nuclear Magnetic Resonance). This thesis describes the research carried out towards the development of new methods for enantiorneric excess determination of amino acids and not naturally occuring α-alkylated amino acids by means of NMR techniques.
Topology Control in VANET and Capacity Estimation
International audienceSome safety applications using VANET exchange a large amount of data, and consequently require an important network capacity. In this paper, we focus on extended perception map applications, that use information from local and distant sensors to offer driving assistance (autonomous driving, collision warning, etc). Extended perception requires a high bandwidth that might not be available in practice in classical IEEE 802.11p ad hoc networks. Therefore, we propose an adaptive power control algorithm optimized for this particular application. We show through an analytical model and a large set of simulations that the network capacity is then significantly increased
A Unified View on Solving Objective Mismatch in Model-Based Reinforcement Learning
Model-based Reinforcement Learning (MBRL) aims to make agents more
sample-efficient, adaptive, and explainable by learning an explicit model of
the environment. While the capabilities of MBRL agents have significantly
improved in recent years, how to best learn the model is still an unresolved
question. The majority of MBRL algorithms aim at training the model to make
accurate predictions about the environment and subsequently using the model to
determine the most rewarding actions. However, recent research has shown that
model predictive accuracy is often not correlated with action quality, tracing
the root cause to the \emph{objective mismatch} between accurate dynamics model
learning and policy optimization of rewards. A number of interrelated solution
categories to the objective mismatch problem have emerged as MBRL continues to
mature as a research area. In this work, we provide an in-depth survey of these
solution categories and propose a taxonomy to foster future research
Book Reviews
Andrew Singleton, Mary Lou Rasmussen, Anna Halafoff and Gary Bouma, Freedoms, Faiths and Futures: Teenage Australians on Religion, Sexuality and Diversity - Dixon
Neil Francis, Religiosity in Australia - Hughes
Jason Goroncy and Rod Pattenden, Imagination in an Age of Crisis: Soundings from the Arts and Theology - Lambert
Robert Dixon and Mary Eastham, Encountering God: Practical theology and the mission to heal, Explorations in Practical Theology series - Maher
Hughes, Philip. Australia’s Religious and Non-Religious Profiles: Analysis of the 2021 Census Data - Rei
The Australian Space Eye: studying the history of galaxy formation with a CubeSat
The Australian Space Eye is a proposed astronomical telescope based on a 6U
CubeSat platform. The Space Eye will exploit the low level of systematic errors
achievable with a small space based telescope to enable high accuracy
measurements of the optical extragalactic background light and low surface
brightness emission around nearby galaxies. This project is also a demonstrator
for several technologies with general applicability to astronomical
observations from nanosatellites. Space Eye is based around a 90 mm aperture
clear aperture all refractive telescope for broadband wide field imaging in the
i and z bands.Comment: 19 pages, 14 figures, submitted for publication as Proc. SPIE 9904,
9904-56 (SPIE Astronomical Telescopes & Instrumentation 2016
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