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The scalar median filter (SMF) is often used to reduce noise in scalar geophysical data. We present an extension of the SMF to a vector median filter (VMF) for suppressing noise contained in geophysical data represented by multidimensional, multicomponent vector fields. Although the SMF can be applied to each component of a vector field individually, the VMF is applied to all components simulta...

The automated approximation of solutions to differential equations which involve discontinuities across evolving surfaces is addressed. Finite element technology has developed to the point where it is now possible to model evolving discontinuities independently of the underlying mesh, which is particularly useful in simulating failure of solids. However, the approach remains tedious to program,...

We propose a new edge detection method that is effective on multivariate irregular data in any domain. The method is based on a local polynomial annihilation technique and can be characterized by its convergence to zero for any value away from discontinuities. The method is numerically cost efficient and entirely independent of any specific shape or complexity of boundaries. Application of the ...

[1] Seismic velocity discontinuities within the top 1000 km of the Earth beneath southern Africa are imaged by stacking about 1300 source-normalized broadband seismograms recorded by the Southern African Seismic Experiment. The Moho, 410, and 660 kilometer discontinuities are clearly detected. The mean mantle transition zone thickness is 245 km, essentially the same as the global average, sugge...

The object of this report is to establish the theoretical range of radio frequency impedance of the human body in the 1-30 MHz ringe. The report dtifines whole body rf impedance, sunmarized available specific tissue impedance data, and predicts likely values of total body impedance for various electrode sizes and locations from known specific tissue data and skin impedance. The report also disc...

[1] Recent observations of ridge bathymetry suggest magmatic segmentation at fastand intermediatespreading centers is linked to the migration of the spreading axis over the mantle. At fastand intermediatespreading centers, Carbotte et al. (2004) observed that leading segments, those that are offset in the direction of ridge migration, are typically shallower (interpreted to be magmatically robu...

The wave impedance and the environment impedance are important for the wave-variable based teleoperator. It is difficult to get good performance when the parameters are not proper. The paper addresses how to design the wave based teleoperator when working environment undergoes changed. It is concluded that wave impedance should match environment impedance by discussing how wave impedance and en...

In this paper, a novel approach based on the Thévenin tracing is presented to modified conventional impedance-based out-of-step (OOS) protection. In conventional approach, the OOS detection is done by measuring positive sequence impedance. However, the measured impedance may be change due to different factors such as capacitor bank switching and reactive power compensators that it can cause the...

Introduction The description of a fault model includes the fault surfaces and associated tip lines, the fault network geometry, and the displacement geometry of faults. Fault surfaces are usually observed from seismic discontinuities, which include reflector breaks, flexures, and amplitude changes. These discontinuities can often have a regular appearance that corresponds to fault geometries fo...