The earthquake motion at a given point on the surface is commonly represented by elastic response spectra. Seismic codes, however, do not distinguish between ground in county side or within an urban environment. traditional spectra are function of seismological, geological, and geotechnical parameters they based prediction free-field surface, hence, considering propagation seismic waves soil de...

Nikos E. Kouvaris, Thomas Isele, Alexander S. Mikhailov, and Eckehard Schöll Departament de F́ısica Fonamental, Universitat de Barcelona, Mart́ı i Franquès 1, 08028 Barcelona, Spain∗ Institut für Theoretische Physik, Technische Universität Berlin, Hardenbergstraße 36, 10623 Berlin, Germany Department of Physical Chemistry, Fritz Haber Institute of the Max Planck Society, Faradayweg 4-6, 14195 Ber...

We present a method for estimating seismic attenuation based on frequency shift data. In most natural materials, seismic attenuation increases with frequency. The high-frequency components of the seismic signal are attenuated more rapidly than the low-frequency components as waves propagate. As a result, the centroid of the signal’s spectrum experiences a downshift during propagation. Under the...

We investigate reaction-diffusion systems near parameter values that mark the transition from an excitable to an oscillatory medium. We analyze existence and stability of traveling waves near a steep pulse that arises as the limit of excitation pulses when parameters cross into the oscillatory regime. Traveling waves near this limiting profile are obtained by analyzing a codimension-two homocli...

it is well-known that dam-reservoir interaction has significant effects on the response of dams to the earthquakes. this phenomenon should be considered more exactly in the seismic design of dams with a rational and reliable dynamic analysis method. in this research, seismic analysis of the dam-reservoir is studied as a wave propagation problem by using legendre spectral element method (sem). t...

Determination of the internal stability of reinforced soil walls under earthquake conditions is an important part of seismic design. The horizontal method of slices is used for determining internal stability or for tieback analysis of the reinforced soil wall. A pseudo-dynamic method is adopted in the present analysis, which considers the effect of phase difference in both the shear and primary...

This paper reviews recent work, much of it unpub~shed, on the effects of anisotropy on seismic waves, and lays the theoretical background for some of the other papers in this number of the Geophysical Journal. The propagation of both body and surface waves in anisotropic media is fundamentally different from their propagation in isotropic media, although the differences in behaviour may be comp...

Spontaneous waves of excitation in the developing mammalian retina are mediated, to a large extent, by neurotransmission. However, it is unclear how the underlying neurotransmitter systems interact with each other to play specific roles in the formation of retinal waves at various developmental stages. In particular, it is puzzling why the waves maintain a similar propagation pattern even after...