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Comparison Between the Nutations of the Planet Mars and the Nutations of the Earth
Surveys in Geophysics, 2000The nutations of the planets Mars andEarth are investigated and compared. Alarge number of interior structureparameters are involved in the nutationcomputations. The comparison between the observations and the computationsprovides several constraints on these parmeters andtherefore allows a better understanding of the physics of the interior of ...
V. Dehant, T. Van Hoolst, P. Defraigne
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Residual nutation angle of satellites with viscous nutation dampers
Acta Astronautica, 1987Abstract The residual nutation angle of satellites with the viscous fluid dampers is one of the important indexes for designing the spinning satellites of high nutation precision. This paper will specifically discuss the reasons why the viscous dampers make the residual angle occur.
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A search for free core nutation modes in VLBI nutation observations
Physics of the Earth and Planetary Interiors, 1995Abstract In recent decades much effort has been devoted to searching observations for evidence of free core nutations predicted by theoretical models. Polar phototube data, tidal gravity observations and very long baseline nutation measurements have all been used.
Xianhua Jiang, D.E. Smylie
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2007
This chapter aims to explore and describe the physiological aspects of oscillating growth patterns in rapidly elongating plant organs, such as roots, hypocotyls , shoots, branches and flower stalks. After a brief description of the phenomena, the theories and models proposed to explain circumnutation are reported, focusing largely on the internal ...
Sergio Mugnai +4 more
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This chapter aims to explore and describe the physiological aspects of oscillating growth patterns in rapidly elongating plant organs, such as roots, hypocotyls , shoots, branches and flower stalks. After a brief description of the phenomena, the theories and models proposed to explain circumnutation are reported, focusing largely on the internal ...
Sergio Mugnai +4 more
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Control characteristics of the ALMA Nutator
2010 IEEE International Conference on Control Applications, 2010The control of a 75 centimeter diameter Atacama Large Millimeter/submillimeter Array (ALMA) [1] nutating subreflector, or Nutator, to meet the specifications of 10 millisecond (ms) settle time and 1.3 arc-second pointing error involves tremendous challenges.
Homin Jiang, Ming-Tang Chen, J. C. Han
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Nutational stimulated photon echoes
Optics Letters, 2002Stimulated photon echoes (SPEs) with time duration comparable to the coherent lifetime and Rabi period have been investigated theoretically and experimentally with an angled beam configuration. The Rabi oscillation effects on both the transmitted field (optical nutation) and the SPE fields are explained by analytic solutions of Maxwell-Bloch equations.
Mingzhen, Tian +3 more
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Link between the retrograde-prograde nutations and nutations in obliquity and longitude
Celestial Mechanics & Dynamical Astronomy, 1995The nutations of the Earth can be seen as variations in longitude and in obliquity of the position of the Celestial Ephemeris Pole (CEP); these variations are given for each nutation frequency, and correspond to an elliptical motion of the CEP in the inertial space.
P. Defraigne, V. Dehant, P. P�quet
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INITIATION OF NUTATION IN SUNFLOWER HYPOCOTYLS
1981Publisher Summary This chapter discusses the initiation of nutation in sunflower hypocotyls. If, prior to the onset of nutating activity, one could see random walk type movements by the epicotyl that in time grow large enough to elicit a gravitropic response with overshoot, then one should interpret this as additional support for the validity of ...
A H, Brown, D K, Chapman
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Possible Temporal Variations of the Free Core Nutation and Forced Nutations
1998The IAU 1980 nutation daily offsets in longitude (δψ) and obliquity (δψ) from VLBI observations are analyzed by wavelet and multistage filter methods. Results suggest that the temporal variations of the free core nutation(FCN) is more intense than those of the annual nutation.
Li Jinling, Zheng Dawei
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“Nutation” of electron spins in biradicals
Journal of Magnetic ResonanceIn this work, the nutation of the spins of unpaired electrons in the nitroxide biradical of bis‑methano[60]fullerene was experimentally studied. Nutation frequencies were found in a wide range of microwave field power. To interpret the obtained results, numerical calculations of the nutation of biradicals were carried out for a set of parameters of the
Ruslan, Zaripov +2 more
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