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Application of Grey Model GM(1, 1) to Ultra Short-Term Predictions of Universal Time

. Journal of Geodesy , 85 (7), 435-441. Gross, R.S., Marcus, S.L., Eubanks, T.M., Dickey, J.O. and Keppenne, C.L. (1996). Detection of an ENSO Signal in Seasonal Length-of-day Variations. Geophysical Research Letters , 23 (23), 3373-3376. Gross, R.S., Eubanks, T.M., Steppe, J.A., Freedman, A.P., Dickey, J.O. and Runge, T.F. (1998). A Kalman-filter-based Approach to Combining Independent Earth-orientation Series. Journal of Geodesy , 72 (4), 215-235. Guo, J.Y., Li, Y.B., Dai, C.L. and Shum, C.K. (2013). A Technique to Improve the Accuracy of Earth

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Cantilever Beam Natural Frequencies in Centrifugal Inertia Field


In the advanced mechanical science the well known fact is that the gravity influences on the natural frequencies and modes even for the vertical structures and pillars. But, the condition that should be fulfilled in order for the gravity to be taken into account is connected with the ration between the gravity value and the geometrical cross section inertia. The gravity is related to the earth acceleration but for moving structures there exist many other acceleration exaggerated forces and such are forces caused by the centrifugal accelerations. Large rotating structures, as wind power generators, chopper wings, large antennas and radars, unfolding space structures and many others are such examples. It is expected, that acceleration based forces influence on the structure modal and frequency properties, which is a subject of the present investigations.

In the paper, rotating beams are subject to investigations and modal and frequency analysis is carried out. Analytical dependences for the natural resonances are derived and their dependences on the angular velocity and centrifugal accelerations are derived. Several examples of large rotating beams with different orientations of the rotating shaft are presented. Numerical experiments are conducted. Time histories of the beam tip deflections, that depict the beam oscillations are presented.

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Sub-Diurnal Earth Rotation Variations Observed by VLBI

References Artz T., Bockmann S., Nothnagel A., Steigenberger P. (2010) Sub-diurnal variations in the Earth's rotation from continuous VLBI campaigns, J. Geophys. Res. , in press. Bizouard C., Gambis D. (2009) The combined solution C04 for Earth orientation parameters consistent with international terrestial reference frame 2005, Geodetic Reference Frames , Vol. 134 of IAG Symposium , Springer, Munich, Germany. Böckmann S., Artz T., Nothnagel A. (2010) VLBI terrestrial reference

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Overview and Performance of the Ukrainian SLR Station "Lviv-1831"

, pp. 135-143, July 2002. ILRS Report SLR Global Performance Report Card ITRF web site UCEOP - Ukrainian Center for Earth Orientation Parameters

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Spectral Characteristic of Polar Motion in the 2005-2006 and 1999-2000 Winters Seasons

/semidiurnal polar motion revisited, J. Geophys. Res. , 109, B11407, doi:10.10292004JB003054. Eubanks T.M., J.A. Steppe, J.O. Dickey, R.D. Rosen, and D.A. Salstein (1988) Causes of rapid motions of the Earth's pole, Nature , 334 115-119. Gross R.S. (2000) The excitation of the Chandler wobble, Geophys. Res. Lett. , 27(15) 23292332. Gross R. S. Fukumori, I. and Menemenlis, D., (2005) Atmospheric and Oceanic Excitation of Decadal-Scale Earth : Orientation Variations, J. Geophys. Res., vol. 110, B09405

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Geodynamic Research at the Department of Planetary Geodesy, SRC PAS

maximum entropy spectral analysis - Part II: Fortran program, Geophysics, 45, 433-446. IERS, 2016, Earth orientation parameters, Jin S.G., Chambers P. , and Tapley D. (2010). Hydrological and oceanic effects on polar motion from GRACE and models, Journal of Geophysical Research, doi: 10.1029/2009JB006635. Jin S.G., Hassan A., and Feng G.P. (2012). Assessment of terrestrial water contributions to polar motion from GRACE and hydrological models, Journal of Geodynamics, 62, 40

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Finite Element Modelling for Tensile Behaviour of Thermally Bonded Nonwoven Fabric

References [1] Rawal A, Priyadarshi A, Kumar N, Lomov S.V, Verpoest I. Tensile behaviour of nonwoven structures: comparison with experimental results. (2010). Journal of Materials Science, 45(24): 6643-6652. [2]Hou X.N, Acar M, Silberschmidt V.V. Finite element simulation of low-density thermally bonded nonwoven materials: Effects of orientation distribution function and arrangement of bond points. (2011). Computational Materials Science, 50(4): 1292-1298. [3]Ridruejo A, González C, Llorca J. Micromechanisms of deformation and fracture of polypropylene

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COCOS: A New Sinex Combination Software

Bundesamts für Kartographie und Geodäsie, Frankfurt am Main. Brockmann E. (1997) Combination of Solutions for Geodetic and Geodynamic Application of the Global Positioning System (GPS): Ph.D Dissertation, Bern, 211 p. Dach R., Hugentobler U., Frider P., Meindl M. (Eds.) (2007) Bernese GPS Software Version 5.0, Bern, Stampfli Publishing AG, 612 p. Gambis D. (2004) Monitoring Earth orientation using space-geodetic techniques: state-of-art and prospective, Journal of Geodesy , Vol. 78, No. 4-5, pp

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Research on Deep Joints and Lode Extension Based on Digital Borehole Camera Technology

References 1. CHEN Jian-ping, SHI Bing-feng, WANG Qing. Study of the dominant orientations of random fractures of fractured rock masses[J]. Chinese Journal of Rock Mechanics and Engineering, 2005, 24(12): 241-245. 2. JIANG Jian-ping, ZHANG Yang-song, LUO Guo-yu, et al. The application of preferred plane theory to geotechnical engineering practice [J]. Journal of Hydraulic Engineering. 2001, 16(8): 90-96. 3. John Kemeny, Randy Post. Estimating three-dimensional rock discontinuity orientation from digital images

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Analysis of Parameters which Affect Regularity of Air Flow in Perforated Pipe

References Dutta, P., Dutta, S. (1998). Effect of baffle size, perforation, and orientation on internal heat transfer enhancement. International Journal of Heat and Mass Transfer, 41, 3005-3013. Greig, D., Siddiqui, K,. Karava, P. (2012). An experimental investigation of the flow structure over a corrugated waveform in a transpired air collector. International Journal of Heat and Fluid Flow, 38, 133-144. Hwang, J-J. (1995). Heat transfer in a rectangular channel with perforated turbulence promoters using

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