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Huang Liren,Han Yueping,Gao Yanlong,Zheng Zhijiang,Fu Liming,

大地测量与地球动力学 , 2012,
Abstract: Several issues concerning the problrms and their concrete solutions that need to be solved in the application of elevation component time series of GNSS continuous operation station coordinates in vertical crustal movement studying are introduced.
Gravitational Waves from Supersymmetry Breaking  [PDF]
Nathaniel J. Craig
Physics , 2009,
Abstract: In theories of supersymmetry breaking, it is often the case that there is more than one metastable vacuum. First-order phase transitions among such metastable vacua may generate a stochastic background of gravitational waves, the observation of which would provide a direct window into the supersymmetry-breaking sector.
A laboratory study of breaking waves  [cached]
Jaros3aw Têgowski
Oceanologia , 2004,
Abstract: This paper deals with some aspects of the wave-breaking phenomenon. The objectives were to study wave-breaking criteria, and the probability of whitecap coverage under fully controlled wave conditions. An additional task was to in vestigate the characteristic spectral features of the noise produced by breaking waves and the acoustic energy generated during wave breaking events. A controlled experiment was carried out in the Ocean Basin Laboratory at MARINTEK, Trondheim (Norway). Waves were generated by a computer-controlled multi-flap wave maker, which reproduced a realistic pattern of the sea surface for the prescribed spectra. Using wave staff recordings and photographic techniques, correlations between the breaking parameters and the radiated acoustic emissions were established.
МЕТОДИКА РОЗРАХУНКУ ГЛИБИНИ ЗАНУРЕННЯ МОРСЬКО ЕНЕРГЕТИЧНО СТАНЦ ПРИ ЗБ ЛЬШЕНН ВИСОТИ ХВИЛЬ Method of calculating the depth of immersion of sea power station with an increase in height of the waves Методика расчета глубины погружения морской энергетической станции при увеличении высоты волн  [cached]
К.?. Кап?танчук,П.?. Греков,В.В. Овсянк?н
Proceedings of National Aviation University , 2006,
Abstract: Розроблено методику розрахунку глибини занурення морсько енергетично станц з робочим елементом роторного типу при зб льшенн висоти морських хвиль. Developed method of calculation of depth immersion of the marine power station with the taking in element of rotor type at the increase of height of marine waves. Разработана методика расчета глубины погружения морской энергетической станции с рабочим элементом роторного типа при увеличении высоты морских волн.
Comparison of elevation heights using a Differential Global Positioning System (DGPS) and a Total Station
Marín, L. E.;Balcazar, M;Ortiz, M;Steinich, B;Hernández-Espriu, J. A.;
Geofísica internacional , 2008,
Abstract: differences in elevation for a set of 12 different points were determined using a total station and a dgps three receivers with occupation times of 90 minutes per station). a comparison between both sets of elevation values shows differences of two to 36 millimeters for a maximum baseline of 2,420 meters. these results show that differential gps surveys may be used to determine differences in elevation using the differential gps technique.
Short Note: Comparison of elevation heights using a differential global positions system (DGPS) and a total station
L. E. Marín,M. Balcazar,M. Ortiz,B. Steinich
Geofísica internacional , 2008,
Abstract: Differences in elevation for a set of 12 different points were determined using a Total Station and a DGPS three receivers with occupation times of 90 minutes per station). A comparison between both sets of elevation values shows differences of two to 39 millimeters for a maximum baseline of 2,420 meters. These results show that differential GPS surveys may be used to determine differences in elevation using the differential GPS technique.
Investigation of Low-Grazing-Angle Microwave Backscattering from Threedimensional Breaking Sea Waves
Wei Luo;Min Zhang;Chao Wang;Hong-Cheng Yin
PIER , 2011, DOI: 10.2528/PIER11062607
Abstract: The microwave backscattering of the sea surface is investigated with the wedge-shaped breaking waves for the super events at low grazing angles (LGA). According to the relationship between the wave breaking and the whitecap, the finite three-dimensional wedges are utilized to approximately model the breaking waves, of which the spatial distribution is simulated with whitecap coverage. The phase-modified two-scale method (TSM) and method of equivalent currents (MEC) are used to calculate the surface and volume scattering of sea surface and breaking waves respectively. The sea spikes in LGA are observed by this model, and the strong directionality is caused by the breakers. Considering the Bragg phase velocity, orbital motion of facets and wind drift, the Doppler spectrum is simulated with the time series of sea clutter. Included the breaking waves, the scattering model indicates that the enhanced non-Bragg scattering leads to the extended Doppler spectrum width. The numerical results agree with the measured data well at LGA. Compared with the statistical models, the complex physical mechanism of the sea scattering is explicitly described in this paper.
Around the cusp singularity and the breaking of waves  [PDF]
J. Tejerina-Risso,P. Le Gal
Physics , 2012,
Abstract: We record the breaking of water waves focusing at the Huygens Cusp of a parabolic wave maker using a fast video camera at a rate of 2000 images per second. The movie shows the very early time of the water tongue plunging ahead of the wave crest. Soon after, some capillarity wavelets are clearly visible. The image analysis of these space time data permits the measurement of the expected 3/2 power of time law as dictated by the cusp singular geometry given by the Catastrophe Theory. To our knowledge this is the first time that this scaling law is measured from fluid dynamics videos.
Using wavelet spectrum analysis to resolve breaking events in the wind wave time series
P. C. Liu,A. V. Babanin
Annales Geophysicae (ANGEO) , 2004,
Abstract: This paper presents the development of a new approach, based on wavelet spectrum analysis, for the detection of breaking waves in a time series of surface wave fluctuations. The approach is shown to be capable of producing equivalent wave breaking statistics as field measurements based on detection of whitecaps at a fixed point of observation. This wavelet-based approach is applicable to both deep water and finite depth environments. Based on applications of this approach to the analysis of available field data, a novel classification of wave breaking processes that consists of incipient, developing, and subsiding phases is proposed.
Breaking the M-waves  [PDF]
JM Figueroa-O'Farrill
Physics , 1999, DOI: 10.1088/0264-9381/17/15/306
Abstract: We present a systematic attempt at classification of supersymmetric M-theory vacua with zero flux; that is, eleven-dimensional lorentzian manifolds with vanishing Ricci curvature and admitting covariantly constant spinors. We show that there are two distinct classes of solutions: static spacetimes generalising the Kaluza-Klein monopole, and non-static spacetimes generalising the supersymmetric wave. The classification can be further refined by the holonomy group of the spacetime. The static solutions are organised according to the holonomy group of the spacelike hypersurface, whereas the non-static solutions are similarly organised by the (lorentzian) holonomy group of the spacetime. These are subgroups of the Lorentz group which act reducibly yet indecomposably on Minkowski spacetime. We present novel constructions of non-static vacua consisting of warped products of d-dimensional pp-waves with (11-d)-dimensional manifolds admitting covariantly constant spinors. Our construction yields local metrics with a variety of exotic lorentzian holonomy groups. In the process, we write down the most general local metric in d<6 dimensions describing a pp-wave admitting a covariantly constant spinor. Finally, we also discuss a particular class of supersymmetric vacua with nonzero four-form obtained from the previous ones without modifying the holonomy of the metric. This is possible because in a lorentzian spacetime a metric which admits parallel spinors is not necessarily Ricci-flat, hence supersymmetric backgrounds need not satisfy the equations of motion.
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