R A Hansen

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Data on underground nuclear explosions have recently become available from modern digital seismic stations installed within the Soviet Union and China. Observations of root mean square (rms) Lg-wave signals for Soviet underground nuclear explosions at the Shagan River Test Site in East Kazakhstan show that the relative amplitudes of the rms signals at(More)
We use a viscous slide model of JIANG and LEBLOND (1994) coupled with nonlinear shallow water equations to study tsunami waves in Resurrection Bay, in south-central Alaska. The town of Seward, located at the head of Resurrection Bay, was hit hard by both tectonic and local landslide-generated tsunami waves during the MW 9.2 1964 earthquake with an epicenter(More)
A regional seismic network in northern Norway, SEISNOR, was installed in 1986 and became operational early in 1987. The network consists of six stations with altogether 24 sensors and with interstation distances from 200 to about 1000 km. The stations are independent and remotely accessible. An automated decision system on a central computer polls the(More)
In this work a numerical modeling method is used to study tsunami waves generated by the Great Alaska earthquake of 1964 and their impact on Kodiak Island communities. The numerical model is based on the nonlinear shallow water equations of motion and continuity which are solved by a finite-difference method. We compare two different source models for the(More)
We analyze the supermodes in multiple coupled photonic crystal waveguides for long-wavelengths. In the tight-binding limit we obtain analytic results that agree with fully numerical calculations. We find that when the field flips sign after a single photonic crystal period, and there is an odd number of periods between adjacent waveguides, the supermode(More)
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