Ray parameters and focal depths.

FOCAL POINT AND FOCAL K-PLANE

This paper deals with the basic notions of k-tautimmersions . These notions come from two special cases; that is, tight and taut immersions. Tight and taut based on high and distance functions respectively and their basic notions are normal bundle, endpoint map, focal point, critical normal. We generalize hight and distance functions to cylindrical function and define basic notions of k-taut ...

Simulation of Cosmic Ray Muon Flux at Shallow Depths Underground

Geant4 has been used to estimate the rate, energy spectrum and angular distribution of cosmic ray muons at underground depths between 300 and 1000 m.w.e. The results agree well with those from the MUSIC program when the same surface spectrum is used. Care has been taken to use a parameterization of the surface spectrum which agrees well with data for the relevant energies. 1 Goals Knowledge of ...

Determination of Earthquake Focal Depths and Source Time Functions in Central Asia Using Teleseismic P Waveforms

We developed a new method to determine earthquake source time functions and focal depths. It uses theoretical Green’s function and a time-domain deconvolution with positivity constraint to estimate the source time function from the teleseismic P waveforms. The earthquake focal depth is also determined in the process by using the time separations of the direct P and depth phases. We applied this...

EARTHQUAKE FOCAL DEPTHS AND SOURCE PARAMETERS IN THE ZAGROS MOUNTAINS Patrick Applegate Richard Alley REFINING MORAINE AGE ESTIMATES FROM COSMOGENIC EXPOSURE DATES USING THE MAXIMUM LIKELIHOOD METHOD Brett

Hidden Depths

The radiograph on this issue’s front cover demonstrates a normal image of the abdomen. It is a favourite of mine and one that I use routinely in teaching undergraduate medical students. Take a good look. You may notice a curvilinear gas density projected within the pelvis. See it? This is what a tampon looks like (figure 1). It’s a subtle finding, but once seen, the radiographic configuration i...