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Nutation and Reference Frame [PDF]
Highlights of Astronomy, 1995 The reference frames are of fundamental importance in all kinds of the precession and nutation studies involving the theory, the coordinate transformation and the observations. The aim of this paper is to review all the frames used in such studies and to lead to a better consistency between them in order that theory and reductions of observations be ...
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The Earth's Constitution and the Nutations [PDF]
Symposium - International Astronomical Union, 1980 The theoretical researches on this subject were first developed in a consistent theory, in 1765, by Euler, who studied the theory of the motion of a rotating rigid body. Bradley shortly before, in 1737, had discovered the first forced nutation, with a period of 18.6 years, which was explained by d'Alembert.
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Accurate free and forced rotational motions of rigid Venus [PDF]
, 2010 % context :The precise and accurate modelling of a terrestrial planet like Venus is an exciting and challenging topic, all the more interesting since it can be compared with that of the Earth for which such a modelling has already been achieved at the ...
Carpenter +21 more
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Free core nutation: new large disturbance and connection evidence with geomagnetic jerks [PDF]
, 2015 Variations in free core nutation (FCN) are connected with various processes in the Earth's fluid core and core-mantle coupling, which are also largely responsible for the geomagnetic field variations, particularly the geomagnetic jerks (GMJs). A previous
Malkin, Zinovy
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MathematicsIn view of the problems of the complex design, difficult machining, and high manufacturing cost of a traditional nutation reducer, this paper intends to design a nutation reducer and study its meshing performance.
Haoyu Chen, Qinghai Li, Chao Jia
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EVALUATION OF OUTER CORE VISCOSITY INFLUENCE ON THE EARTH FORCED NUTATION
Odessa Astronomical Publications, 2007 On the base of the combined method, consisting of the Sasao, Okubo, Saito (1980) approach with the iteration procedure, allowing couple finite element method with the solution of the Laplace equation, it have evaluated the influence of outer core ...
M. V. Lubkov
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Detection of Phase Jumps of Free Core Nutation of the Earth and their Concurrence with Geomagnetic Jerks [PDF]
, 2004 We detected phase jumps of the Free Core Nutation (FCN) of the Earth directly from the analysis of the Very Long Baseline Interferometer (VLBI) observation of the Earth rotation for the period 1984-2003 by applying the Weighted Wavelet Z-Transform (WWZ ...
A Toomre +20 more
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Optimal Design of Single-stage Double-arc Spiral Bevel Gear Nutation Reducer
Jixie chuandong, 2020 According to the nutation motion principle，a new single-stage double circular-arc spiral bevel gear nutation reducer with simple structure and large transmission ratio is designed， and its transmission ratio calculation formula is obtained.
Zheng Lin +3 more
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The effect of the differential rotation of the earth inner core on the free core nutation
Geodesy and Geodynamics, 2019 Seismic observations shows that the inner core rotates faster than the mantle and the rotation axis of the inner core may not align with the rotation axis of the mantle. Free core nutation reflects core's information.
Mian Zhang, Chengli Huang
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IEEE Access, 2019 Considering the wear in mechanical bearings and the requirement for sensors or electrical power in active magnetic bearings, a novel nutation blood pump using a passive magnetic spherical bearing was developed in this paper.
Gang Chen +4 more
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