5,190 research outputs found

    Stochastic Gravitational Wave Measurements with Bar Detectors: Dependence of Response on Detector Orientation

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    The response of a cross-correlation measurement to an isotropic stochastic gravitational-wave background depends on the observing geometry via the overlap reduction function. If one of the detectors being correlated is a resonant bar whose orientation can be changed, the response to stochastic gravitational waves can be modulated. I derive the general form of this modulation as a function of azimuth, both in the zero-frequency limit and at arbitrary frequencies. Comparisons are made between pairs of nearby detectors, such as LIGO Livingston-ALLEGRO, Virgo-AURIGA, Virgo-NAUTILUS, and EXPLORER-AURIGA, with which stochastic cross-correlation measurements are currently being performed, planned, or considered.Comment: 17 pages, REVTeX (uses rcs, amsmath, hyperref, and graphicx style files), 4 figures (8 eps image files

    Ergonomic Standards for Pedestrian Areas for Disabled People: Methodology and Sample Identification

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    This project is a TRRL research contract, the aim of which is to produce guidance on the design of pedestrian areas and footways for elderly and disabled people. The first part of the project was a literature review and consultation exercise, the objective of which was to identify key impediments for investigation. The second part of the project involved the detailed survey work on the key impediments. This Working Paper reports upon the development of the second part of the project and, in particular, upon the identification of the sample of disabled people to be used in the detailed interview and observation work. The sample identification involved contacting some 3000 disabled people listed in official disability registers, and 250 ablebodied people via on-street interviews. From the disabled sample approximately 500 people were interviewed in order to find out more about their disability and to assess the usefulness of a preliminary disability categorisation system; their activity rate; problems they experience in using pedestrian areas and footways; and their willingness to take part in further stages of the study. From the interviews, a sample of people in each of the revised categories, together with samples of the elderly and the ablebodied, were selected for an observation phase in which those involved were observed completing a movement distance exercise, and using different types of pedestrian facility, in central Leeds

    Ergonomic standards for pedestrian areas for disabled people: literature review and consultations

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    As part of the project for the Transport and Road Research Laboratory concerned with the development of design guidance for pedestrian areas and footways to satisfy the needs of disabled and elderly people, a thorough examination of the literature was required. In addition the literature search was to be complemented by a wide-ranging series of discussions with local authorities, organisations representing the interests of elderly and disabled people, and other interested agencies. This Working Paper sets out the findings of this exercise. The objective of the literature review and the consultations was to identify the key impediments for elderly and disabled people when using pedestrian areas and footways. The current guidelines and standards relating to footways, pedestrianised areas and access to buildings were to be identified and their adequacy commented upon, as were the conflicts such recommendations raise between various groups of disabled people and with able-bodied people. The consultations were intended to provide greater insights into what the literature highlighted, and to suggest possible solutions. The literature review produced over 400 key references and a list of 35 impediments. A more detailed examination of the literature and the consultations reduced this list to six key impediments namely: parking; public transport waiting areas; movement distances; surface conditions; ramps, and information provision. The type and scale of problem created by the above impediments for various groups of disabled and elderly people are discussed, together with their measurement and assessment. The type and adequacy of existing design standards and guidance relating to these impediments are also outlined

    Economic Standards for Pedestrian Areas for Disabled People: Results from Observation Work

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    1.1.1 The Institute for Transport Studies was invited by the Transport and Road Research Laboratory to submit a research proposal, with costs, aimed at establishing suitable "Ergonomic Standards for Pedestrian Areas for Disabled People". The project commenced on 1st July, 1986 and was split into two parts, with part one involving four months' work over the period to 31st December, 1986 and part two finishing on 30th April, 1988. 1.1.2 The -objectives of the study laid down in the design brief by the Transport and Road Research Laboratory were: a) To produce a guide to good practice for the design and maintenance of footways and pedestrianised areas; b) To provide, where possible, recommended standards for design and maintenance. The good practice guide and the recommended standards were to be primarily aimed at disabled people and the elderly, but the requirements of the able-bodied were also to be considered, as were conflicts between the needs of different groups of user. The economic implications of implementation and maintenance were also to be detailed. (Continues..

    Economic Standards for Pedestrian Areas for Disabled People: Results of the Initial and Main Interview

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    1.1.1 The Institute for Transport Studies was invited by the Transport and Road Research Laboratory to submit a research proposal, with costs, aimed at establishing suitable llErgonomic Standards for Pedestrian Areas for Disabled People". The project commenced on 1st July, 1986 and was split into two parts, with part one involving four monthso work over the period to 31st December, 1986 and part two finishing on 30th April, 1988. 1.1.2 The main objectives of the Study laid down in the design brief by the Transport and Road Research Laboratory were: a) To produce a guide to good practice for the design and maintenance of footways and pedestrianised areas; b) To provide, where possible, recommended standards for design and maintenance. The good practice guide and the recommended standards were to be primarily aimed at disabled people and the elderly, but the requirements of the able-bodied were also to be considered, as were conflicts between the needs of different groups of user. The economic implications of implementation and maintenance were also to be detailed

    Ergonomic Standards for Pedestrian Areas for Disabled People: Results from Observation Work

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    1.1.1 The Institute for Transport Studies was invited by the Transport and Road Research Laboratory to submit a research proposal, with costs, aimed at establishing suitable "Ergonomic Standards for Pedestrian Areas for Disabled People". The project commenced on 1st July, 1986 and was split into two parts, with part one involving four months' work over the period to 31st December, 1986 and part two finishing on 30th April, 1988. 1.1.2 The -objectives of the study laid down in the design brief by the Transport and Road Research Laboratory were: a) To produce a guide to good practice for the design and maintenance of footways and pedestrianised areas; b) To provide, where possible, recommended standards for design and maintenance. The good practice guide and the recommended standards were to be primarily aimed at disabled people and the elderly, but the requirements of the able-bodied were also to be considered, as were conflicts between the needs of different groups of user. The economic implications of implementation and maintenance were also to be detailed. (Continues..

    Accretion-ejection connection in the young brown dwarf candidate ISO-Cha1 217

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    As the number of observed brown dwarf outflows is growing it is important to investigate how these outflows compare to the well studied jets from young stellar objects. A key point of comparison is the relationship between outflow and accretion activity and in particular the ratio between the mass outflow and accretion rates (M˙out\dot{M}_{out}/M˙acc\dot{M}_{acc}). The brown dwarf candidate ISO-ChaI 217 was discovered by our group, as part of a spectro-astrometric study of brown dwarfs, to be driving an asymmetric outflow with the blue-shifted lobe having a position angle of \sim 20^{\circ}. The aim here is to further investigate the properties of ISO-ChaI 217, the morphology and kinematics of its outflow, and to better constrain (M˙out\dot{M}_{out}/M˙acc\dot{M}_{acc}). The outflow is spatially resolved in the [SII]λλ6716,6731[SII]\lambda \lambda 6716,6731 lines and is detected out to \sim 1\farcs6 in the blue-shifted lobe and ~ 1" in the red-shifted lobe. The asymmetry between the two lobes is confirmed although the velocity asymmetry is less pronounced with respect to our previous study. Using thirteen different accretion tracers we measure log(M˙acc\dot{M}_{acc}) [Msun_{sun}/yr]= -10.6 ±\pm 0.4. As it was not possible to measure the effect of extinction on the ISO-ChaI 217 outflow M˙out\dot{M}_{out} was derived for a range of values of Av_{v}, up to a value of Av_{v} = 2.5 mag estimated for the source extinction. The logarithm of the mass outflow (M˙out\dot{M}_{out}) was estimated in the range -11.7 to -11.1 for both jets combined. Thus M˙out\dot{M}_{out}/M˙acc\dot{M}_{acc} [\Msun/yr] lies below the maximum value predicted by magneto-centrifugal jet launching models. Finally, both model fitting of the Balmer decrements and spectro-astrometric analysis of the Hα\alpha line show that the bulk of the H I emission comes from the accretion flow.Comment: accepted by Astronomy & Astrophysic

    Develop and test fuel cell powered on site integrated total energy sysems: Phase 3: Full-scale power plant development

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    A 25-cell stack of the 13 inch x 23 inch cell size (about 4kW) remains on test after 8300 hours, using simulated reformate fuel. A similar stack was previously shut down after 7000 hours on load. These tests have been carried out for the purpose of assessing the durability of fuel cell stack components developed through the end of 1983. A 25kW stack containing 175 cells of the same size and utilizing a technology base representative of the 25-cell stacks has been constructed and is undergoing initial testing. A third 4kW stack is being prepared, and this stack will incorporate several new technology features

    Searching for numerically-simulated signals of black hole binaries with a phenomenological template family

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    Recent progress in numerical relativity now allows computation of the binary black hole merger, whereas post-Newtonian and perturbative techniques can be used to model the inspiral and ringdown phases. So far, most gravitational-wave searches have made use of various post-Newtonian-inspired templates to search for signals arising from the coalescence of compact binary objects. Ajith et al have produced hybrid waveforms for non-spinning binary black-hole systems which include the three stages of the coalescence process, and constructed from them phenomenological templates which capture the features of these waveforms in a parametrized form. As a first step towards extending the present inspiral searches to higher-mass binary black-hole systems, we have used these phenomenological waveforms in a search for numerically-simulated signals injected into synthetic LIGO data as part of the NINJA project

    An Economic Evaluation of Irish Salmon Fishing General Summary of Results. ESRI Memorandum Series No. 99 1974

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    The purpose of the study was to investigate the economies of salmon fishing in Ireland. Essentially, it set out to answer the question "how valuable was the Irish salmon industry to the economy in 1970?" In order to answer this question, the study tried to evaluate the economic impact of angling and commercial fishing on the various districts, determine the capacity of the industry for future development and provide information to assist in the more effective marketing of salmon and sea-trout angling. Although the survey was confined to 1970, its findings may be updated for subsequent years by means of the regularly published data on catches and numbers of licences, and by appropriate price indices
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