Results 261 to 270 of about 1,103,532 (303)
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Intensity patterns of solar ultraviolet radiation
Environmental Research, 1977Abstract Using field measurements of ultraviolet radiation, intensity patterns by time of day and time of year are examined. Depending on location, 39 to 80% of the half-hourly readings of sufficient intensity to produce minimum erythema occur between 10:00 am and 2:00 pm during the late spring and early summer months of May through August.
J, Scotto, T R, Fears
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Patterns of coevolution in the adaptive radiation of crossbills
Annals of the New York Academy of Sciences, 2010Although evidence for coevolution and geographic variation in its apparent strength is increasing, we still have a relatively poor understanding of why coevolution varies among interactions. Here we review how variation in the occurrence of competitors, resource stability, habitat area, and time has affected the extent of trait escalation in ...
Craig W, Benkman +2 more
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Beam-shaped radiation pattern for uniform radiated power distribution
2014 IEEE Latin-America Conference on Communications (LATINCOM), 2014This paper presents the application of optimization methods for the synthesis of antenna arrays. The desired pattern shall exhibit a shape that allows uniform distribution of the radiated power on the Earth. Besides beamshaping, the optimization methods allow controlling the level of the sidelobes.
Edson R. Schlosser +3 more
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Radiation Pattern of Parabolic Reflector
IETE Technical Review, 1999Radiation pattern of parabolic reflector can be computed using various numerical methods. Moment method is convenient for small objects in terms of wavelength. When the dimension of the radiating objects are large compared to wavelength, high frequency asymptotic techniques like GTD (Geometrical Theory of Diffraction) gives very accurate results in ...
K Saroja, S Sanyal
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Some relations between the radiation patterns in the two main planes and the whole radiation pattern
Annales Des Télécommunications, 1996Dans les etudes theoriques, le champ lointain rayonne par une antenne est souvent calcule en utilisant une integrale de rayonnement qui fournit un resultat en un point quelconque de l’espace. De maniere concrete, l’interet se porte en general sur deux coupes dans deux plans principaux, appeles plan E et plan H. Au vu des references bibliographiques, il
Patrick Vaudon +2 more
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Waveforms and Radiation Patterns
1984In numerous technical applications, as well as some theoretical considerations, an enticing problem is encountered. In its most practical (and real) form the problem may be that of designing a radar (or sonar) transmitter waveform with a given spectrum such that its peak factor is a minimum.
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On the radiation pattern of a paraboloid of revolution
Applied Scientific Research, 1955The radiation pattern of a paraboloid of revolution is determined by using the mathematical form of Huygens’ principle where the field intensities in a given domain are expressed in their tangential components on the boundary. These tangential components are supposed to have the values which follow from the reflection of a plane wave at an infinite ...
Schouten, J. P., Beukelman, B. J.
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Radiation therapy‐associated toxicity: Etiology, management, and prevention
Ca-A Cancer Journal for Clinicians, 2021Kyle Wang
exaly
Calculating antenna radiation patterns
Electrical Engineering, 1944CALCULATIONS of the horizontal relative field patterns of antennas are long and laborious and increase in complexity with the number of antenna elements employed. Present calculating machines are useful only for antenna-beam arrays consisting of not over three elements.
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