10 research outputs found

    Conceptual Design of a High-Resolution, Low Cost Topographic Mapping Mission

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    There is a need for space-based topographic mapping missions which are an order-of-magnitude less costly than the 100MclassmissionscurrentlyplannedbyNASAandthecommercialcommunity.TheStereoImagingLongLookSatellite(STILLSAT),havingamassofapproximately100kg,isdesignedfor5minstantaneousfieldofview(IFOV)tomeetmostofthetopographicrequirementsofboththescienceandcartographycommunity.TheresultingDigitalElevationModels(DEM)arepredictedtohave10m(absolute)contourintervals,geocorrectedbygrounddatum.FrameandpanoramiccamerasfromApollo15,16,and17,aswellasESA2˘7sMetricCamerasandtheU.S.LargeFormatCamerahavebeencitedbyphotogrammetristsasadvantageousfortopographicmapproduction.TheuseofaCCDframingcameraforstereoimagingwasdiscussedbyJPLin1979butdismissedbecauseCCDtechnologywasnotyetmatureenough.BycapitalizingonrecentadvancesinCCDtechnologyandinstitutingaconceptofsharedstabilityandpointingresponsibilitybetweenthebusandpayload,itisnowpossibletoconsidersuchanadvancedmission.Thispaperwillfocusonthesystemengineeringtradesresultingfrommissionrequirementsthatdictateearth/satellitemotioncompensationtoachieveveryhighspatialresolution,aswellasoffaxiscrosstrackimagingtomaximizetargetacquisition.Themissionisapproachedfromanintegrateddesignparadigmwhereinscience,instrument,bus,andgroundoperationsobjectivesaresimultaneouslyweighedtoachieveextremelylowcost,lowpower,andreliablemissionelements.TheinitialSTILLSATmissionoperationsplanistoobtainmultiplestereoimagesatbaseheightratiosof1.0withintargetsofopportunityof100kmindiametertosupportspecificscienceobjectives.STILLSATisdesignedforlineofsightpointingtowithin0.1degreeandcanimageoffaxisupto20degreesinthecrosstrackdirection.Thetotalspacecraftandmissionoperationscostisexpectedtobewellunder100M-class missions currently planned by NASA and the commercial community. The Stereo Imaging Long-Look Satellite (STILLSAT), having a mass of approximately 100 kg, is designed for 5m instantaneous field of view (IFOV) to meet most of the topographic requirements of both the science and cartography community. The resulting Digital Elevation Models (DEM) are predicted to have 10m (absolute) contour intervals, geo-corrected by ground datum. Frame and panoramic cameras from Apollo 15, 16, and 17, as well as ESA\u27s Metric Cameras and the U.S. Large Format Camera have been cited by photogrammetrists as advantageous for topographic map production. The use of a CCD framing camera for stereo imaging was discussed by JPL in 1979 but dismissed because CCD technology was not yet mature enough. By capitalizing on recent advances in CCD technology and instituting a concept of shared stability and pointing responsibility between the bus and payload, it is now possible to consider such an advanced mission. This paper will focus on the system engineering trades resulting from mission requirements that dictate earth/satellite motion compensation to achieve very high spatial resolution, as well as off-axis cross track imaging to maximize target acquisition. The mission is approached from an integrated design paradigm wherein science, instrument, bus, and ground operations objectives are simultaneously weighed to achieve extremely low cost, low power, and reliable mission elements. The initial STILLSAT mission operations plan is to obtain multiple stereo images at base height ratios of 1.0 within targets-of-opportunity of 100km in diameter to support specific science objectives. STILLSAT is designed for line-of-sight pointing to within 0.1 degree and can image off-axis up to 20 degrees in the cross track direction. The total spacecraft and mission operations cost is expected to be well under 5M (not including launch) and is being initially proposed as a Student Explorer Development Initiative (STEDI) project to the Universities Space Research Association\u27s Advanced Design Program. A launch could occur within 24 months of go-ahead. Progressively advanced concepts of this approach will be discussed, those which can map much larger regions of the Earth through use of larger detector arrays and mosaicked images. It is even conceivable that a STILLSAT-derived single global mapping satellite or constellation of simpler satellites could provide worldwide coverage. This approach holds promise for both scientific and commercial applications

    Accessing and engaging women from socio-economically disadvantaged areas: a participatory approach to the design of a public health intervention for delivery in a Bingo club

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    Background Our aim was to use participatory methods to investigate the feasibility and acceptability of using Bingo clubs for the design and delivery of an evidence-based physical activity and/or healthy eating intervention to socio-economically disadvantaged women. This paper describes the participatory process that has resulted in a physical activity intervention for women aged >55years, ready for pilot-testing in a Bingo club setting. Methods Studies using different quantitative and qualitative approaches were conducted among customers and staff of a Bingo club in a city of 85,000 inhabitants in central Scotland. These were designed to take the views of different stakeholders into account, with a view to enhancing uptake, engagement and effectiveness with any proposed intervention. Results Sixteen relevant studies were identified in a literature review that generated ideas for intervention components. A questionnaire completed by 151 women in the Bingo club showed that almost half (47%) aged >55years were not meeting physical activity guidelines; evidence backed up by accelerometer data from 29 women. Discussions in six focus groups attended by 27 club members revealed different but overlapping motivations for attending the Bingo club (social benefits) and playing Bingo (cognitive benefits). There was some scepticism as to whether the Bingo club was an appropriate setting for an intervention, and a dietary intervention was not favoured. It was clear that any planned intervention needed to utilise the social motivation and habitual nature of attendance at the Bingo club, without taking women away from Bingo games. These results were taken forward to a 5-h long participative workshop with 27 stakeholders (including 19 Bingo players). Intervention design (form and content) was then finalised during two round table research team meetings. Conclusions It was possible to access and engage with women living in areas of socio-economic disadvantage through a Bingo club setting. A physical activity intervention for women >55years is realistic for recruitment, will address the needs of potential recipients in the Bingo club, appears to be feasible and acceptable to club members and staff, and has been designed with their input. A pilot study is underway, investigating recruitment, retention and feasibility of delivery

    Star Scanner Attitude Determination for the OSO-7 Spacecraft

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    Emission Spectrometry

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    ATSDR Evaluation of Health Effects of Chemicals. V. Xylenes: Health Effects, Toxicokinetics, Human Exposure, and Environmental Fate

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