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Polar motion of the triaxial nonrigid Earth and atmospheric excitation

Wei Chen, Wenbin Shen
2011 Geo-spatial Information Science  
We re-formulate the Liouville equations and their general solutions for the triaxial nonrigid Earth and find that the traditional theory introduces some theoretical errors in modeling the excitation functions  ...  Thus we conclude that the traditional theory of the rotation of the rotational-symmetric Earth should be revised and upgraded to include the effects of the Earth's triaxiality.  ...  Introduction In a previous study by , [1] the atmospheric excitation of polar motion for a rotational-symmetric (i.e. A = B), single-layer and elastic Earth model was discussed.  ... 
doi:10.1007/s11806-011-0517-9 fatcat:5rvfrlbfibetjbzpwk4jgpysqe

Atmospheric excitation of polar motion

Wei Chen, Wenbin Shen, Xiaowei Dong
2010 Geo-spatial Information Science  
The polar motion excited by the fluctuation of global atmospheric angular momentum (AAM) is investigated.  ...  Based on the global AAM data, numerical results demonstrate that the fluctuation of AAM can excite the seasonal wobbles (e.g., the 18-month wobble) and the Chandler wobble, which agree well with previous  ...  Discussion and conclusion In this paper, the atmospheric excitation of polar motion is studied both theoretically and numerically for the case of a biaxial Earth (just following the traditional theory)  ... 
doi:10.1007/s11806-010-0042-2 fatcat:4zqc2b7t6vbsvh2m3ykmlybpri

The multiple-frequency Chandler wobble

Cheh PAN
1982 Journal of Physics of the Earth  
The problem of the excitation and damping of the Chandler wobble is reviewed and the conventional models analyzed.  ...  Using an axially near-symmetric and slightly triaxial Earth Model, a solution of the Liouville equation reveals that the Chandler wobble has multiple frequency and is rather a quasipermanent phenomenon  ...  From the above analysis we can see that an Earth under polar excitation is axially near-symmetirc and slightly triaxial.  ... 
doi:10.4294/jpe1952.30.389 fatcat:gqppixfohvfmtlr4b44yf7xrxi

Polar motion of Titan forced by the atmosphere

Tetsuya Tokano, Tim Van Hoolst, Özgür Karatekin
2011 Journal of Geophysical Research  
The atmospheric excitation of Titan's polar motion is calculated using the wind and pressure data prediction from a general circulation model.  ...  1] Titan's atmosphere possesses an equatorial component of angular momentum, which can be transferred to the surface and can excite polar motion of Titan.  ...  The factor 2/3a accounts for the relative difference between the mean and polar MOI. [14] The dynamical polar flattening is defined as ¼ C À AþB 2 AþB 2 ð9Þ Atmospheric Excitation of Polar Motion [15  ... 
doi:10.1029/2010je003758 fatcat:4645mc3ghjfi7lidq5u3fu62mq

Commission 19: Rotation of the Earth (Rotation de la Terre)

Nicole Capitaine, Véronique Dehant, G. Beutler, P. Brosche, A. Brzeziński, T. Fukushima, D. Gambis, R. Gross, J. Hefty, C. Huang, Z. Malkin, D. McCarthy (+8 others)
2002 Transactions of the International Astronomical Union  
All the contributors to this report from IERS, IVS and various institutes involved in Earth rotation studies are sincerely acknowledged. Nicole Capitaine President of the Commission  ...  The correlation of seasonal and subseasonal variations of the geodetic and atmospheric excitation functions of polar motion were studied.  ...  They have revealed the importance of specific areas for polar motion excitation. The results also confirm that oceans supplement the atmosphere as an important source of polar motion excitation.  ... 
doi:10.1017/s0251107x00001267 fatcat:4j6lnpqmdbd2zdokpvpbd3mtsi

Free polar motion of a triaxial and elastic body in Hamiltonian formalism: Application to the Earth and Mars

M. Folgueira, J. Souchay
2005 Astronomy and Astrophysics  
Moreover we emphasize the large oscillations of Mars' polar motion due to the triaxiality of this planet.  ...  of the Earth and the motion of its angular momentum axis, with respect to an Earth-fixed reference frame, after showing the influence of the choice of the origin on these coordinates, and on the determination  ...  This research was carried out in the Department of "Systèmes de Référence Temps Espace" (SYRTE), Paris Observatory, under a combination of a financial support of Paris Observatory ( 2003 ) and Descartes  ... 
doi:10.1051/0004-6361:20041312 fatcat:fwf7vlvrcbgd5dufonhv2zohqu

The period and Q of the Chandler wobble

M. L. Smith, F. A. Dahlen
1981 Geophysical Journal International  
One of us (MLS) enjoyed the hospitality of the Department of Geological and Geophysical Sciences of Princeton University during the Fall of 1979.  ...  This research was supported by the National Aeronautics and Space Administration (NASS-25887 at CIRES, NAS5-25896 at Princeton), the National Science Foundation (EAR78-01713 at Princeton), and the Alfred  ...  This service still operates, although it has been largely superseded by the International Polar Motion Service (IPMS), organized in 1962, and by the Bureau International de 1'Heure (BIH), which added polar  ... 
doi:10.1111/j.1365-246x.1981.tb02667.x fatcat:vihhatbcsjcblp67dbgrk65bjq

The results of a unique Nordic HAKK interlaboratory REAT comparison

Torben Poulsen
1999 Journal of the Acoustical Society of America  
and for the selective advantage during the evolutionary development of a complex ear structure. ͓  ...  On the accuracy of the assessment of room acoustical parameters using MLS technique and ray-tracing simulation Also, the following poster sessions are scheduled: Poster Session 3aAOa Poster Session 3aPPb  ...  The force along the bow is transformed into a force couple at the bridge feet which excites the bridge and body. The broad maximum involves resonant motion which is not confined to the bridge alone. ͓  ... 
doi:10.1121/1.425267 fatcat:6pa5rsq5zjcanl55hcxmwa743u

High‐intensity, focused ultrasonic fields

Leif Bjørnoø
1988 Journal of the Acoustical Society of America  
The tutorial will briefly handle the precision of the measurements. A great deal of time will be devoted to examples of applications on radiation from simple and complex sources and their nearfields.  ...  The tutorial will cover the fundamentals of all aspects of the intensity technique. Basic theoretical relationships of sound energy generation and propagation will be discussed.  ...  Magnetostrictive rare earth-iron rods are presently mainly used as active elements of emission transducers. In this case, rods are mechanically prestressed and magnetically polarized.  ... 
doi:10.1121/1.2025494 fatcat:yhmkhlqhivbwnp2lxraret33iq

Memoria 2012 [article]

CSIC-Instituto De Estructura De La Materia (IEM), Digital.CSIC, Digital.CSIC
This approach is applied to nonrigid biphenyl-like molecules displaying a large amplitude motion corresponding to respective rotations of their two groups.  ...  We construct and analyze the triaxial energy surfaces that provide the landscape of the energy as a function of the quadrupole deformation parameters.  ...  DATOS COMPARATIVOS CON LAS PREVISIONES DEL PLAN ESTRATÉGICO / DATA COMPARED TO EXPECTATIONS FROM THE STRATEGIC PLAN *Includes data of BSc courses.  ... 
doi:10.20350/digitalcsic/10647 fatcat:7vnxfxhbszfajiffqmupldec3a