18,234 research outputs found

    Friction brake cushions acceleration and vibration loads

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    Friction brake cushions an object in a vehicle from axially applied vibration and steady-state acceleration forces. The brake incorporates a doubly tapered piston that applies a controlled radial force to friction brake segments bearing against the walls of a cylinder

    Working Effectively with Employees who Have Epilepsy

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    This brochure on employees who have epilepsy and the Americans with Disabilities Act (ADA) is one of a series on human resources practices and workplace accommodations for persons with disabilities edited by Susanne M. Bruyère, Ph.D., CRC, SPHR, Director, Program on Employment and Disability, School of Industrial and Labor Relations – Extension Division, Cornell University. Cornell University was funded in the early 1990’s by the U.S. Department of Education National Institute on Disability and Rehabilitation Research as a National Materials Development Project on the employment provisions (Title I) of the ADA (Grant #H133D10155). These updates, and the development of new brochures, have been funded by Cornell’s Program on Employment and Disability, the Pacific Disability and Business Technical Assistance Center, and other supporters

    Supersymmetric Lifshitz-like backgrounds from N=4 SYM with heavy quark density

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    We examine a class of gravity backgrounds obtained by considering the backreaction of a spatially uniform density of mutually BPS Wilson lines or heavy quarks in N=4 SUSY Yang-Mills theory. The configurations preserve eight supercharges and an SO(5) subgroup of the SO(6) R-symmetry. They are obtained by considering the 1/4-BPS geometries associated to smeared string/D3-brane (F1-D3) intersections. We argue that for the (partially) localized intersection, the geometry exhibits a flow from AdS_5 x S^5 in the UV to a novel IR scaling solution displaying anisotropic Lifshitz-like scaling with dynamical critical exponent z=7, hyperscaling violation and a logarithmic running dilaton. We also obtain a two-parameter family of smeared 1/4-BPS solutions on the Coulomb branch of N=4 SYM exhibiting Lifshitz scaling and hyperscaling violation. For a certain parametric range these yield IR geometries which are conformal to AdS_2 x R^3, and which have been argued to be relevant for fermionic physics.Comment: 24 pages, 2 figures, references added, version published in JHEP, Feb. 201

    Water system virus detection

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    The performance of a waste water reclamation system is monitored by introducing a non-pathogenic marker virus, bacteriophage F2, into the waste-water prior to treatment and, thereafter, testing the reclaimed water for the presence of the marker virus. A test sample is first concentrated by absorbing any marker virus onto a cellulose acetate filter in the presence of a trivalent cation at low pH and then flushing the filter with a limited quantity of a glycine buffer solution to desorb any marker virus present on the filter. Photo-optical detection of indirect passive immune agglutination by polystyrene beads indicates the performance of the water reclamation system in removing the marker virus. A closed system provides for concentrating any marker virus, initiating and monitoring the passive immune agglutination reaction, and then flushing the system to prepare for another sample

    Results from a VLT-ISAAC survey of ices and gas around young stellar objects

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    General results from a 3-5 micron spectroscopic survey of nearby low-mass young stellar objects are presented. L and M-band spectra have been obtained of \~50 low mass embedded young stars using the ISAAC spectrometer mounted on UT1-Antu at Paranal Observatory. For the first time, a consistent census of the CO, H2O ices and the minor ice species CH3OH and OCN- and warm CO gas present around young stars is obtained, using large number statistics and resolving powers of up to R=10000. The molecular structure of circumstellar CO ices, the depletion of gaseous CO onto grains in protoplanetary disks, the presence of hot gas in the inner parts of circumstellar disks and in outflows and infalls are studied. Furthermore, the importance of scattering effects for the interpretation of the spectra have been addressed.Comment: To appear in the proceedings of the conference "Chemistry as a Diagnostic of Star Formation", University of Waterloo, Canada, 21-23 August 200

    Obituary: Arthur Cruickshank 1932 - 2011. A native Gondwanan, who studied the former continent's fossil tetrapods

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    Dr Arthur Richard Ivor Cruickshank died on 4th December 2011, aged 79, in the Borders General Hospital, Melrose, Scotland. Arthur Cruickshank was part of the post-war generation of palaeontologists who laid the foundations on which today’s researchers build. Appropriately for someone from an expatriate Scots family living in Kenya, much of his work was on the extinct reptiles of the great southern palaeocontinent of Gondwana

    International Cooperation in Hydrography and Modern Techniques in Hydrographic Surveying

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    There is nothing more timely and urgent than the need for promoting international cooperation in hydrography and for considering the development, uses and need for employing modern techniques in hydrographic surveying. The International Hydrographic Organization has always given particular attention to international cooperation in hydrography in the widest sense. The role played by IHO and the manner in which FIG could possibly assist IHO in promoting international cooperation in hydrography are explained in the address. The period since World War II has probably seen more changes than any similar period in the history of the world. The impact of these changes has been such that charts of many of the world’s economically strategic waterways were made obsolete and inadequate, while maritime trade developed in many new areas where existing charts were found hopelessly inadequate. While regional or sub-regional cooperative efforts are a means by which hydrographic surveying and nautical charting programmes could lead to more adequate and up-to-date charts, the problems of developing countries that have little or no hydrographic capability need very special attention. As in other fields, hydrographic surveying has witnessed spectacular technological advances in recent years. This technology and future developments must be exploited to the full and their benefits must not be limited to the few. The establishment and strengthening of hydrographic capabilities of developing countries through international cooperation are vital to the attainment of the IHO’s objective of providing up-to-date charts, based on internationally accepted standards, which in turn would benefit the international maritime community in an increasingly interdependent world

    Paper Session II-A - Space Station Assured Crew Return Vehicle (ACRV) System and Operational Considerations

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    The Space Station currently is being designed to maximize crew safety through fault tolerance, safehaven provisions, and crew delivery and return using the Space Transportation System (STS). Studies have identified the need for assured crew return capability through a space-based lifeboat that is always available for use in contingencies encompassing (1) medical emergencies, (2) Space Station failures, and (3) interruption of STS services. This paper reviews major mission, operational, and system requirements and the process for evaluating a range of practical vehicle and operational options. It describes flight and ground system design concepts and the major trade studies being performed to select the best end-to-end system that will provide a basis for design and development. Flight vehicles include capsules with ballistic and low lift/drag characteristics and lifting body aerodynamic-shaped designs. Ground systems emphasize the use of existing resources
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