10,715 research outputs found

    Illumination from space with orbiting solar-reflector spacecraft

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    The feasibility of using orbiting mirrors to reflect sunlight to Earth for several illumination applications is studied. A constellation of sixteen 1 km solar reflector spacecraft in geosynchronous orbit can illuminate a region 333 km in diameter to 8 lux, which is brighter than most existing expressway lighting systems. This constellation can serve one region all night long or can provide illumination during mornings and evenings to five regions across the United States. Preliminary cost estimates indicate such an endeavor is economically feasible. The studies also explain how two solar reflectors can illuminate the in-orbit nighttime operations of Space Shuttle. An unfurlable, 1 km diameter solar reflector spacecraft design concept was derived. This spacecraft can be packaged in the Space, Shuttle, transported to low Earth orbit, unfurled, and solar sailed to operational orbits up to geosynchronous. The necessary technical studies and improvements in technology are described, and potential environmental concerns are discussed

    Lunar landing flight research vehicle Patent

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    Lunar landing flight research vehicl

    Upper atmosphere research: Reaction rate and optical measurements

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    The objective is to provide photochemical, kinetic, and spectroscopic information necessary for photochemical models of the Earth's upper atmosphere and to examine reactions or reactants not presently in the models to either confirm the correctness of their exclusion or provide evidence to justify future inclusion in the models. New initiatives are being taken in technique development (many of them laser based) and in the application of established techniques to address gaps in the photochemical/kinetic data base, as well as to provide increasingly reliable information

    Development of an externally powered prosthetic hook for amputees

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    The powered hook with trigger finger appears to be a useful adaptation of a terminal device for an amputee when performing vocational activities involving the use of a powered tool requiring a trigger control. The proportional control system includes transducers and amplifiers and appears to have widespread application for control of any external power, whether it be in the orthotic or prosthetic field

    Using the LANDSAT data collection system for field geophysics: Operations in the British Virgin Islands

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    This particular application was to vertical geodesy by tide gauge and tiltmeter on a small desert island in the British Virgin Islands. The performance of the LANDSAT system under potentially marginal circumstances was found to be excellent

    The effect of lower limb strengthening exercise on orthostatic blood pressure and the skeletal muscle pump in older people with orthostatic hypotension

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    \ua9 2023 The Authors. Clinical Physiology and Functional Imaging published by John Wiley & Sons Ltd on behalf of Scandinavian Society of Clinical Physiology and Nuclear Medicine.Introduction: Activation of muscles during standing is recommended to activate the skeletal muscle pump, increasing venous return and increasing blood pressure (BP) in people with orthostatic hypotension (OH). Aim: The aim of this study is to determine if increasing the strength of the lower limb muscles can improve the effectiveness of the venous pump and postural BP in older people with OH. Methods: Ten older people with OH underwent an 8-week lower limb strengthening intervention. Repeated measurements of orthostatic BP, calf venous ejection fraction (EF) and muscle strength took place before, during and after intervention. Results: The intervention increased calf muscle strength by 21% (interquartile range: 18–28), p = 0.018, from a median baseline of 38 (34–45) kg. Participants had normal levels of venous EF 64% (51–75) at baseline, with little to no venous reflux. The median ejection volume at baseline was 44 (36–58) mL per calf. Despite increasing muscle strength, venous EF did not increase (percentage change −10% (−16 to 24), p = 0.8) and systolic BP drop did not improve (percentage change 0% (−17 to 16), p = 1.0). Similarly, visual analysis of individual case-series trends revealed increasing muscle strength with no clinically meaningful change in EF or orthostatic BP. Conclusions: Muscle strengthening exercise does not increase the effectiveness of the skeletal muscle pump and is not an efficacious intervention for OH. As there is little to no venous pooling in the calf during standing in older people with OH, below knee compression is unlikely to be clinically effective

    Use of thermal inertia determined by HCMM to predict nocturnal cold prone areas in Florida

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    The HCMM transparency scenes for the available winter of 1978-1979 were evaluated; scenes were identified on processed magnetic tapes; other remote sensing information was identified; and a soil heat flux model with variable-depth thermal profile was developed. The Image 100 system was used to compare HCMM and GOES transparent images of surface thermal patterns. Excellent correspondence of patterns was found, with HCMM giving the greater resolution. One image shows details of thermal patterns in Florida that are attributable to difference in near surface water contents. The wide range of surface temperatures attributable to surface thermal inertia that exist in the relatively flat Florida topography is demonstrated

    Use of thermal inertia determined by HCMM to predict nocturnal cold prone areas in Florida

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    Transparencies, prints, and computer compatible tapes of temperature differential and thermal inertia for the winter of 1978 to 1979 were obtained. Thermal inertial differences in the South Florida depicted include: drained organic soils of the Everglades agricultural area, undrained organic soils of the managed water conservation areas of the South Florida water management district, the urbanized area around Miami, Lake Okeechobee, and the mineral soil west of the Everglades agricultural area. The range of wetlands and uplands conditions within the Suwanee River basin was also identified. It is shown that the combination of wetlands uplands surface features of Florida yield a wide range of surface temperatures related to wetness of the surface features

    Use of thermal inertia determined by HCMM to predict nocturnal cold prone areas in Florida

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    Surface temperatures derived from HCMM data were compared with to those obtained by GOES satellite and the apparent thermal inertia (ATI) calculated. For two dates, the HCMM temperatures appear to be about 5 C lower than the GOES temperatures. The ATI for excessively-drained to well-drained mineral soils was greater than for drained organic soils possibly because of long periods of low rainfall during late 1980 and early 1981. Organic soils cropped to sugar cane showed lower ATI after a severe killing freeze. With dead leaves, there was less transpiration and more solar radiation probably reached the dark soil surface. This would explain the larger diurnal temperature amplitude observed

    Community Relationships and Population Dynamics of Terrestrial Mammals of Isle Royale, Lake Superior, 1967-1968

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    Second Annual Report (Covering the nineth year in the Isle Royale Studies) 1967-1968https://digitalcommons.mtu.edu/wolf-annualreports/1053/thumbnail.jp
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