Results 261 to 270 of about 1,547,748 (299)
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Bulletin Geodesique, 1982
Based on an analysis of polar motion behavior, we found the possibility of predicting polar motion up to one year in advance. Comparing these predicted polar coordinates with the observed ones (smoothed), the rms of the differences is about 0".02. The differences of the relative polar motion are much smaller.
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Based on an analysis of polar motion behavior, we found the possibility of predicting polar motion up to one year in advance. Comparing these predicted polar coordinates with the observed ones (smoothed), the rms of the differences is about 0".02. The differences of the relative polar motion are much smaller.
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Journal of Geodesy, 2004
Short-term forecast of the polar motion is considered by introducing a prediction model for the excitation function that drives the polar motion dynamics. The excitation function model consists of a slowly varying trend, periodic modes with annual and several sub-annual frequencies (down to the 13.6-day fortnightly tidal period), and a transient decay ...
J O Dickey, R S Gross
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Short-term forecast of the polar motion is considered by introducing a prediction model for the excitation function that drives the polar motion dynamics. The excitation function model consists of a slowly varying trend, periodic modes with annual and several sub-annual frequencies (down to the 13.6-day fortnightly tidal period), and a transient decay ...
J O Dickey, R S Gross
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Polarization contrast and motion detection
Journal of Comparative Physiology A, 2006Form and motion perception rely upon the visual system's capacity to segment the visual scene based upon local differences in luminance or wavelength. It is not clear if polarization contrast is a sufficient basis for motion detection. Here we show that crayfish optomotor responses elicited by the motion of images derived from spatiotemporal variations
Raymon M, Glantz, John P, Schroeter
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Chinese Astronomy and Astrophysics, 1981
Abstract Using the auto-regressive technique, we have analysed data of polar motion, Earth's rotation and excitation function of Earth's atmosphere and obtained their low frequency spectra. These spectra have some periods in common and this fact suggests that these periods are probably real.
Ming Zhao, Da-wei Zheng
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Abstract Using the auto-regressive technique, we have analysed data of polar motion, Earth's rotation and excitation function of Earth's atmosphere and obtained their low frequency spectra. These spectra have some periods in common and this fact suggests that these periods are probably real.
Ming Zhao, Da-wei Zheng
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“Polar”-functions for Brownian motion
Zeitschrift für Wahrscheinlichkeitstheorie und Verwandte Gebiete, 1982Let (Xt)t≧0 denote the 2-dimensional Brownian motion. It is well-known that iff∶R+ →R2 is a constant function, then $$P\{ \exists t > 0\,X_t + f(t) = 0\} = 0.$$
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The Motion of Slow Electrons in a Polar Crystal
Physical Review, 1953A variational technique is developed to investigate the low-lying energy levels of a conduction electron in a polar crystal. Because of the strong interaction between the electron and the longitudinal optical mode of the lattice vibrations, perturbation-theoretic methods are inapplicable.
Lee, T. D., Low, F. E., Pines, D.
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DORIS and the Determination of the Earth’s Polar Motion
Journal of Geodesy, 2006DORIS (Determination d’Orbite et Radiopositionnement Integres par Satellite) is a system used for precise orbit determination (POD) and ground-station positioning. It has been implemented on-board various satellites: the SPOT (Systeme pour l’Observation de la Terre) remote sensing satellites SPOT-2, SPOT-3, SPOT-4, SPOT-5, TOPEX/Poseidon and more ...
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Polarization vision in crayfish motion detectors
Journal of Comparative Physiology A, 2008Motion detector interneurons were examined to determine their responsiveness to the motion of polarized light images (i.e. images segmented by spatial variations in e-vector angle). Computer generated images were displayed as intensity contrasts or polarization contrasts on a modified LCD projection panel.
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Journal of Geodesy, 2002
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Vicente, R. O., Wilson, C. R.
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zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Vicente, R. O., Wilson, C. R.
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Tectonophysics, 1972
Abstract Problems about the origin of polar motions and earth tides, and the accuracies reached in their determination, are discussed. The common references system (C.I.O.) for the measurement of the instantaneous pole of rotation is defined. Hypotheses for the origin of the Chandler wobble are critically reviewed. The importance of the seventy years
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Abstract Problems about the origin of polar motions and earth tides, and the accuracies reached in their determination, are discussed. The common references system (C.I.O.) for the measurement of the instantaneous pole of rotation is defined. Hypotheses for the origin of the Chandler wobble are critically reviewed. The importance of the seventy years
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