Results 161 to 170 of about 333,204 (200)
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Angles of Elevation of the Pyramids of Egypt
The Mathematics Teacher, 1982Only an unfortunately blasé person could stand at the foot of the Great Pyra- mid of Giza without experiencing waves of wonder at its very existence. Everything about it is astonishing-its beauty, its bulk, its history, its mystery. By day it is awesome-a man-made mountain that originally towered 147 meters above its base; a square, 230 meters on a ...
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Interferometer Design for Elevation Angle Estimation
IEEE Transactions on Aerospace and Electronic Systems, 1977Radars that are developed for the purpose of monitoring aircraft landings in the terminal air traffic control system can be designed to exploit the relatively high signal-to-noise ratio that characterizes the power budgets calculated for such a link. An interferometer using a pair of low gain antennas can be used to obtain passive coverage over a targe
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Head Angle and Elevation in Classroom Environments: Implications for Amplification
Journal of Speech, Language, and Hearing Research, 2008PurposeThe purpose of this study was to examine children’s head orientation relative to the arrival angle of competing signals and the sound source of interest in actual school settings. These data were gathered to provide information relative to the potential for directional benefit.MethodForty children, 4–17 years of age, with and without hearing ...
Todd Andrew, Ricketts, Jason, Galster
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Elevation angles and attenuation of gravity waves in the ionosphere
2021<p>&#160;&#160;&#160;&#160; Characteristics of gravity waves (GWs) are studied from multi-point and multi-frequency continuous Doppler sounding in the Czech Republic. Three dimensional (3D) phase velocities of GWs are determined from phase shifts between the signals reflecting from the ionosphere at ...
Jaroslav Chum +3 more
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Corneal Elevation Topography in Primary Open Angle Glaucoma
Journal of Glaucoma, 2017Purpose of the Study: The purpose of the study was to describe and compare anterior and posterior topographic elevation maps in primary open angle glaucoma patients with functional damage staging and in healthy controls. Methods: A total of 217 subjects were consecutively recruited,
Pedro, Gil +6 more
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1969
In spite of the obviously great difficulties in isolating specific effects in the case of near-antipodal propagation, we have seen that, in some instances (for example, the results in fig. 10.9) it is possible to obtain examples which indicate some of the mechanisms operating.
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In spite of the obviously great difficulties in isolating specific effects in the case of near-antipodal propagation, we have seen that, in some instances (for example, the results in fig. 10.9) it is possible to obtain examples which indicate some of the mechanisms operating.
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Refractive Errors in Angle-of-Elevation Measurements
IEEE Transactions on Aerospace and Electronic Systems, 1971It is shown that the errors associated with radio elevation measurements may be investigated systematically using a variational technique. The error occurring when spaced antennas are used is compared with that for a single directional antenna. Integral expressions are obtained for the refractive errors.
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Contact angle of lubricating oils at elevated temperatures
Chemistry and Technology of Fuels and Oils, 19721. Contact angles of lubricating oils on St. 45 steel have been determined at elevated temperatures (up to 180°C), and it has been shown that increasing the temperature leads to a decrease in the contact angle at a rate that is fast at first and then slower. At 180°C, contact angles for the different oils are quite similar. 2.
A. A. Kuznetsov, V. M. Martynov
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Constellations for High Elevation Angles
1998Millimeter wave satellite communication will require high ground elevation angle over large areas. Four orbital constellations which can supply this need are discussed. Elevation angle probability density functions are generated and shown for each of the three constellations.
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Angle of Elevation of Short Wave Rays
Nature, 1932AN important problem in short wave propagation from both the purely scientific and the commercial aspect concerns the angle of elevation of the path of the ray both at the transmitting and receiving end.
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