Wyniki wyszukiwania - BazTech

Ograniczanie wyników

Znaleziono wyników: 2

Liczba wyników na stronie

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: ruchy Ziemi

Sortuj według:

Ogranicz wyniki do:

A Numerical Study of Effects of Valley-Weathering and Valley-Shape-Ratio on the Ground Motion Characteristics

Narayan J. P., Arafat M. Y., Kamal

Acta Geophysica

2015

Vol. 63, no. 1

154--175

A study of combined effects of valley-weathering and valley-shaperatio on the ground motion characteristics and associated differential ground motion (DGM) is documented in this paper. In order to properly quantify the weathering effects, a forth-order-accurate staggered-grid viscoelastic time-domain finite-difference program has been used for the simulation of SH-wave responses. Simulated results revealed that the defocusing caused by valley is frequency-independent in contrast to the ridge-focusing. A decrease of average spectral amplification (ASA) with an increase of shape-ratio of the non-weathered triangular and elliptical valleys was obtained. Overall, the amplification and de-amplification pattern was larger in case of triangular valleys as compared to the elliptical valleys. It can be concluded that the dwelling within or near the topcorners of weathered valleys may suffer more damage as compared to their surroundings. A weathered triangular valley with large shape-ratio may cause unexpected damage very near its top-corners since both the ASA and DGM are largest.

Współczesne wzorce czasu

Dudek Z.

Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

1998

nr 12

858-861

Opisano metodę otrzymywania istotnego dla telekomunikacji umownego uniwersalnego czasu międzynarodowego TAI, uniwersalnego czasu ziemskiego, rolę satelitarnych systemów nawigacyjnych do przesyłania wzorca czasu i perspektywy rozwoju miar czasu.

The methods of the Coordinated Universal Time UTC and the Universal Earth Time UT1 calculations has been presented. The satellite navigation systems time delivery problems are noticed and the future development of these systems.