Seismic Hazard Estimation Based on Non-Poisson Earthquake Occurrences

A non-Poisson earthquake occurrence model for seismic hazard estimation is developed to account for the periodicity and the nonstationarity in seismic activities. The model consists of a renewal process model for major fault systems and a nonstationary Poisson-type model for secondary seismic sources, the latter being dominated by the former. The model is identified on the basis of the historical earthquake data for the Kinki District in the western part of Japan, containing the Kyoto-Osaka-Kobe metropolitan area. A simulation model for seismic hazard estimations (ground acceleration and velocity are dealt with) is then developed by combining the non-Poisson earthquake occurrence model and probabilistic attenuation rules. On the basis of the results of the simulation, the significance of the periodicity and the nonstationarity of seismic activities in assessing the seismic risk is discussed

Backward shifts on function algebras

J.R. Holub (1988) 1101 introduced the concept of backward shift on Banach spaces. We show that an infinite-dimensional function algebra does not admit a backward shift. Moreover, we define a backward quasi-shift as a weak type of a backward shift, and show that a function algebra A does not admit it, under the assumption that the Choquet boundary of A has at most finitely many isolated points.ArticleJOURNAL OF MATHEMATICAL ANALYSIS AND APPLICATIONS. 377(1):135-144 (2011)journal articl

Minimal orbits of the isotropy groups of symmetric spaces of compact type

AbstractLet M be a compact symmetric space, and K the isotropy subgroup of the group of all isometries of M at a point o of M . We consider two actions of K , namely the natural action of K on M and the linear isotropy action of K on the tangent space ToM . In both cases, we show that in each category of orbits of the “same type” under K there exists a unique minimal one