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Results of three years of directional wave measurement at the Eastern Mediterranean coast of Haifa, Israel are presented. The wave-height and energy-flux distributions reveal a moderately high-energy coast with a bimodal annual cycle.The rate of wave-induced longshore sediment transport is estimated from the directional energy flux distributions. It describes an annual cycle with a maximum northward transport of 75 ± 14 × 103 m3/month in midwinter and a southward transport of 26 ± 5 × 103 m3/month in summer. The net annual transport is northward and computed at 110 ± 100 × 103 m3/yr.We show that a wave-induced transport is sufficient in explaining the apparent transport of sediments in the Nile Littoral Cell, from the Nile Delta source to the Haifa Bay sink. 相似文献
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The purpose of this note is to give further information regarding the positions of some condensations around Carinae in 1963, an epoch not yet considered in the literature. The new information is unable to confirm the deceleration hypothesis of theeir motion. 相似文献
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Rodrigo A. Miranda Erico L. Rempel Abraham C.-L. Chian Felix A. Borotto 《Journal of Atmospheric and Solar》2005,67(17-18):1852
There is increasing observational evidence of nonlinear wave–wave interactions in space and astrophysical plasmas. We first review a number of theoretical models of nonlinear wave–wave interactions which our group has developed in the past years. We next describe a nonlinear three-mode truncated model of Alfvén waves, involving resonant interactions of one linearly unstable mode and two linearly damped modes. We construct a bifurcation diagram for this three-wave model and investigate the phenomenon of intermittent chaos. The theoretical results presented in this paper can improve our understanding of intermittent time series frequently observed in space and astrophysical plasmas. 相似文献
6.
Z. Abraham D. Falceta-Gonçalves 《Monthly notices of the Royal Astronomical Society》2010,401(1):687-694
It is believed that η Carinae is actually a massive binary system, with the wind–wind interaction responsible for the strong X-ray emission. Although the overall shape of the X-ray light curve can be explained by the high eccentricity of the binary orbit, other features like the asymmetry near periastron passage and the short quasi-periodic oscillations seen at those epochs have not yet been accounted for. In this paper we explain these features assuming that the rotation axis of η Carinae is not perpendicular to the orbital plane of the binary system. As a consequence, the companion star will face η Carinae on the orbital plane at different latitudes for different orbital phases and, since both the mass-loss rate and the wind velocity are latitude dependent, they would produce the observed asymmetries in the X-ray flux. We were able to reproduce the main features of the X-ray light curve assuming that the rotation axis of η Carinae forms an angle of 29°± 4° with the axis of the binary orbit. We also explained the short quasi-periodic oscillations by assuming nutation of the rotation axis, with an amplitude of about 5° and a period of about 22 days. The nutation parameters, as well as the precession of the apsis, with a period of about 274 years, are consistent with what is expected from the torques induced by the companion star. 相似文献
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Aghdam Ali Taheri Salmasi Farzin Abraham John Arvanaghi Hadi 《Geotechnical and Geological Engineering》2021,39(5):3383-3399
Geotechnical and Geological Engineering - The effects of diameter and location of drain pipes on the uplift force and exit hydraulic gradient for a gravity dam are investigated. A numerical model... 相似文献
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M. A. Subramanian R. D. Shannon B. H. T. Chai M. M. Abraham M. C. Wintersgill 《Physics and Chemistry of Minerals》1989,16(8):741-746
Using fused SiO2, CaF2, and SrF2 samples with accurately known dielectric constants, we have evaluated the accuracy and precision of two-terminal dielectric constant measurements on small single crystals using empirically determined edge corrections. Values of κ′ at 1 MHz of 3.836±0.05 for silica, 6.814±0.07 for CaF2 and 6.463±0.09 for SrF2 indicate an accuracy and precision of 1.0–1.5% for samples having areas of 0.05–1.0 cm2. Dielectric constants of BeO, MgO, and CaO measured by this technique are: BeO, κ′a=6.87 and κ′c=7.74; MgO, κ′= 9.90; and CaO, κ′=11.95 where κ′a and κ′c are the dielectric constants parallel to the a and c axes, respectively. Dielectric loss measurements on CaO in vacuum between 5–400 K at 10–105 Hz indicate significant dispersion at temperatures higher than 300 K, but the effect of the losses on the dielectric constant is less than 1% at 1 MHz and 300 K. 相似文献
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