4,274 research outputs found

    The GSFC gound-based lidar for the measurement of stratospheric ozone

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    Concern has risen over the last decade concerning the release of gases into the atmosphere which when photolyzed in the stratosphere can catalyze the destruction of ozone. Although the expected change is only on the order of 5%, significant changes in the vertical profile are anticipated. Predictions at 40 km run as high as a 60% change in the next 50 to 100 years. Because of the importance of ozone in the thermal budget of the atmosphere, such a change will have a direct impact on the earth's climate. Long term monitoring of stratospheric ozone is required to validate the predictions and Differential Absorption Lidar is particularly well suited to this measurement. GSFC is currently constructing a mobile lidar system based on a high powered XeCl excimer laser. The system is expected to be operating by fall 1986 and a campaign to compare the lidar results with a series of ROCOZ flights is planned

    Rotationally resolved collisional transfer rates in OH

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    Fluorescence lidar measurements of the hydroxyl radical require detailed information concerning collision induced processes in order to deduce the radical number density from a lidar return. The Goddard SFC OH lidar currently utilizes a broadband detector which precludes the necessity of fully understanding collisional redistribution of rotational energy within the excited state. Numerous advantages result however from the inclusion of a detector with a bandpass only slightly larger that the Doppler width of a rotational line. This however places more stringent requirements on the spectroscopy. Measurements were accordingly made of rotationally resolved quenching rates for collisions with O2, N2, and H2O. Rotational transfer rates were also measured for the same colliders. Quenching rates were measured using a Nd-YAG pumped Rh6G dye laser doubled into the UV. The OH lifetimes were measured as a function of pressure of quenching gas at total pressures of between 50 and 250 microns. Rotational transfer rates were measured by recording the emission spectrum on an intensified diode array and integrating over 10.000 laser shots

    Erratum: Is it possible to infer the equation of state of a mixture of hard discs from that of the one-component system?

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    The numerical values in the sixth and seventh columns of table 1 of the paper Molec. Phys., 1999, 96, 1185-1188 are not correct. Consequently, some of the comments made in the paper are wrong. The corrected version of table 1 is reprinted here and the results are briefly discussed.Comment: 2 pages; Erratum to Molec. Phys., 1999, 96, 1185-1188; to be published in Molec. Phy

    SmokeFree Sports Project Report

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    Children and young people are amongst the most vulnerable groups in society and are highly susceptible to smoking experimentation and addiction. In Liverpool, smoking prevalence is significantly higher than the UK average. Therefore early intervention strategies are required for smoking prevention and cessation. Research has found a negative association between smoking and physical activity. SmokeFree Sports aims to explore whether physical activity and sport can be used to promote the smoke free message to children and young people. SmokeFree Sports is an innovative multi-dimensional campaign that incorporates social-marketing strategies alongside the provision of sports and physical activities to: a) de-normalise smoking among youth b) empower youth to stay smoke free, and c) increase awareness of the dangers of smoking using positive messaging through the medium of sport and physical activity. This project is delivered across Liverpool and aims to reduce the prevalence of smoking and prevent the uptake of smoking in children and young people. The initiative, which is managed by Liverpool John Moores University in partnership with Liverpool PCT, employs a variety of strategies to promote and deliver the smoke free message to children and young people including a) training sports coaches and teachers to deliver the smoke free message, b) delivering SFS messages in schools and youth clubs through sport and physical activity, c) asking children to sign a pledge to be smoke free, d) support voluntary sports clubs to adopt a smoke free policy on their playing fields, e) encouraging organizations and individuals interested in health and sport to sign up to the SmokeFree Sports Charter and f) signposting children to smoking cessation services

    Developing strategies for mainstreaming sustainability

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    The objective of this project was to progress the process of mainstreaming sustainable residential development. For the purpose of this report, mainstreaming is defined as the increased acceptance and adoption of sustainable design strategies and technologies by the majority of the building industry and its consumers, the broader community. To achieve this objective the report aims to identify and verify where possible the barriers to mainstreaming sustainable residential development and to recommend solutions to overcome such barriers. The project focussed on three areas Greenfield residential development rather than urban renewal. Institutional constraints (process, people, regulatory etc) more than socio-cultural (education, perception, etc) or technological. The four service areas of Water, Waste and Materials, Transport, and Social sustainability. Interviews of a broad and representative cross section of the development community were combined with other research and related work. This research and consultation was then built on and tested at a workshop involving a similarly representative group. In this report there are four levels of detail related to the key project findings Constraint categories and sub-categories (Shown in Figure 1). For each category, priority constraints, key findings and recommendations (Shown overleaf and in the relevant report section). For each category, all identified and verified constraints (Shown in the summary matrices in the relevant report section). For each identified and verified constraint, contextual detail including ideas for solutions, examples of where the constraints have been overcome and remaining questions surrounding each constraint (Shown in Appendix A). Four major categories of constraint emerged from the interviews and initial research along with associated subcategories

    Discrimination of Individual Tigers (\u3cem\u3ePanthera tigris\u3c/em\u3e) from Long Distance Roars

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    This paper investigates the extent of tiger (Panthera tigris) vocal individuality through both qualitative and quantitative approaches using long distance roars from six individual tigers at Omaha\u27s Henry Doorly Zoo in Omaha, NE. The framework for comparison across individuals includes statistical and discriminant function analysis across whole vocalization measures and statistical pattern classification using a hidden Markov model (HMM) with frame-based spectral features comprised of Greenwood frequency cepstral coefficients. Individual discrimination accuracy is evaluated as a function of spectral model complexity, represented by the number of mixtures in the underlying Gaussian mixture model (GMM), and temporal model complexity, represented by the number of sequential states in the HMM. Results indicate that the temporal pattern of the vocalization is the most significant factor in accurate discrimination. Overall baseline discrimination accuracy for this data set is about 70% using high level features without complex spectral or temporal models. Accuracy increases to about 80% when more complex spectral models (multiple mixture GMMs) are incorporated, and increases to a final accuracy of 90% when more detailed temporal models (10-state HMMs) are used. Classification accuracy is stable across a relatively wide range of configurations in terms of spectral and temporal model resolution

    A Primer on ABLE Accounts

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    Determination of Copper in Lead and Lead Base Alloys

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    This work was undertaken in an effort to develop a rapid method for the determination of copper in the range of 0.01 to 0.06% in lead alloys and in the range of 0.001 to 0.005% in lead. A visual and a photometric method are suggested, based on the color developed by copper in concentrated hydrochloric acid. Iron interferes with the determination, but this interference is reduced by use of an aluminum file in the visual method, and is corrected for in the photometric method by determination of the Lron as the thiocyanate. The visual method is very rapid, is accurate to plus or minus 0.1% in the range 0.01-0.06%, and is suggested as a control method for alloys. The photometric procedure is accurate to better than 0.006% in the range of 0.01 to 0.05% and 0.0005% in the range 0.001 to 0.005%, and is suggested as a routine or control method
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