Results 261 to 270 of about 211,089 (303)

Direct beam radiation: Projection onto tilted surfaces

Solar Energy, 1988
Abstract The projection of direct beam radiation onto tilted surfaces is studied on a daily and monthly basis. Direct tilted values, calculated from hourly beam data, are compared to estimates made by multiplying daily and monthly average direct beam values by the average value of the cosine of the incident angle.
F. Vignola, D.K. McDaniels
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Tilted wave interferometry for testing large surfaces

Fifth European Seminar on Precision Optics Manufacturing, 2018
Measuring large surfaces interferometrically is a straight forward established technology, as long as they are concave and spherical. The situation chnages completely if aspheres and freeforms have to be measured. The application of a Tilted Wave Interferometer opens up possibilities to measure large concave surfaces of any shape without compensation ...
Antonia Harsch, Wolfgang Osten, Christof Pruss, Alexander Haberl   +3 more
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Intrinsic and induced aberration sensitivity to surface tilt

Applied Optics, 1988
L'aberration est exprimee en termes de parametres de construction et de quantites propres au trace des ...
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Valley splitting on tilted Si(100) surfaces

Physics Letters A, 1983
Abstract We have investigated Shubnikov-de Haas (SdH) oscillations and Hall measurements in the inversion layer of surfaces tilted 1.2° from the Si(100) towards the Si(111). SdH measurements reveal two distinct bands, populated approximately in a 4:1 ratio, each with a valley degeneracy of one, which is consistent with valley splitting in a ...
S.M. Goodnick, J.R. Sites, K.S. Yi, D.K. Ferry, C.W. Wilmsen   +4 more
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A tilted transversely isotropic slowness surface approximation

Geophysical Prospecting, 2012
ABSTRACTThe relation between vertical and horizontal slownesses, better known as the dispersion relation, for transversely isotropic media with a tilted symmetry axis (TTI) requires solving a quartic polynomial equation, which does not admit a practical explicit solution to be used, for example, in downward continuation.
Stovas, A., Alkhalifah, Tariq Ali
openaire   +2 more sources

Flow Obstacles Minimize Surface Turbulence in Tilt Casting

Chemical Engineering Science, 2021
Abstract Here we explore mold obstacles as means of attenuating flow and minimizing surface turbulence in tilt casting. Surface turbulence refers surface undulations and droplet pinch off that increase the surface area of the flow, which become defects as metal freezes.
Leonard F. Pease, Jie Bao, Ramuel Safarkoolan, Timothy G. Veldman, Nathan R.J. Phillips, Patrick S. McNeff, Christopher K. Clayton   +6 more
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Slant-tilt: The visual encoding of surface orientation

Biological Cybernetics, 1983
A specific form for the internal representation of local surface orientation is proposed, which is similar to Gibson's (1950) "amount and direction of slant". Slant amount is usually quantified by the angle sigma between the surface normal and the line of sight (0 degrees less than or equal to sigma less than or equal to 90 degrees).
openaire   +2 more sources

Tilted TI models in surface microseismic monitoring

GEOPHYSICS, 2015
A recently published analytic technique for computing locations of microseismic events jointly with velocities of homogeneous isotropic media was extended to surface microseismic monitoring and transversely isotropic models with tilted symmetry axes (TTI). The analysis of traveltimes of the direct P-, SV-, and SH-waves, conducted under the assumptions
openaire   +1 more source

Tilted conic fitting to an off-axis conic surface

Applied Optics, 1991
A better fitting to an off-axis conic section can be obtained if a tilted conic is used. The mathematical equation for the tilting angle is obtained as well as the influence over some of the aberration coefficients.
O, Cardona-Nunez, A, Cornejo-Rodriguez
openaire   +2 more sources

Diffraction Coefficients for Tilted Surface-Breaking Cracks

2002
Many cracks of practical interest in ultrasonic non-destructive testing (NDT) are surface-breaking (Fig. 1). In order to model inspection of such cracks with the geometrical theory of diffraction (GTD), the diffraction coefficients for surface corners need to be calculated.
V. M. Babich, V. A. Borovikov, L. Ju. Fradkin, D. Gridin, V. Kamotski, V. P. Smyshlyaev   +5 more
openaire   +1 more source