A simple method for depth determination from self-potential anomalies due to two superimposed structures

2016 ◽  
Vol 47 (4) ◽  
pp. 308-314 ◽  
Author(s):  
El-Sayed M. Abdelrahman ◽  
Eid R. Abo-Ezz ◽  
Tarek M. El-Araby ◽  
Khalid S. Essa
Keyword(s):  
Simple Method ◽  
Depth Determination ◽  
Self Potential

A least-squares minimisation approach to depth determination from numerical second horizontal self-potential anomalies

2009 ◽  
Vol 40 (2) ◽  
pp. 214-221 ◽  
Author(s):  
El-Sayed Mohamed Abdelrahman ◽  
Khalid Soliman ◽  
Khalid Sayed Essa ◽  
Eid Ragab Abo-Ezz ◽  
Tarek Mohamed El-Araby
Keyword(s):  
Least Squares ◽  
Depth Determination ◽  
Self Potential

A least‐squares approach to depth determination from self‐potential anomalies caused by horizontal cylinders and spheres

Geophysics ◽  
1997 ◽  
Vol 62 (1) ◽  
pp. 44-48 ◽  
Author(s):  
El‐Sayed Mohamed Abdelrahman ◽  
Sharafeldin Mahmoud Sharafeldin
Keyword(s):  
Least Squares ◽  
Maximum Error ◽  
Polarization Angle ◽  
Data Errors ◽  
Depth Determination ◽  
Horizontal Cylinders ◽  
Cylinders And Spheres ◽  
Self Potential ◽  
True Values ◽  
Least Squares Approach

We have developed a least‐squares approach to depth determination from self‐potential anomalies caused by horizontal cylinders and spheres. By defining the zero‐anomaly distance and the anomaly value at the origin on the profile, the problem of depth determination from self‐potential data has been transformed into finding a solution to a nonlinear equation. Procedures are also formulated to estimate the electric dipole moment and the polarization angle. The error in the depth parameter estimation introduced by data errors was also studied through imposing 1 to 10% errors in the zero‐anomaly distance and the anomaly value at the origin in one synthetic profile caused by a sphere. When the zero‐anomaly distance and the anomaly value at the origin possess errors of equal magnitude and of the same signs, the results will not differ much from the true values. When errors have opposite signs, the maximum error in depth is 10%. Finally, the validity of the method is tested on a field example from Ergani Copper district, Turkey.

A Least-squares Approach to Depth Determination from Numerical Horizontal Self-potential Gradients

2004 ◽  
Vol 161 (2) ◽  
pp. 399-411 ◽  
Author(s):  
E. M. Abdelrahman ◽  
H. S. Saber ◽  
K. S. Essa ◽  
M. A. Fouda
Keyword(s):  
Least Squares ◽  
Depth Determination ◽  
Potential Gradients ◽  
Self Potential ◽  
Least Squares Approach

A simple way for producing holographic filters suitable for image improvement

1978 ◽  
Vol 36 (1) ◽  
pp. 226-227
Author(s):  
K.-H. Herrmann ◽  
E. Reuber ◽  
P. Schiske
Keyword(s):  
Transfer Functions ◽  
Diffraction Order ◽  
Lateral Position ◽  
Simple Method ◽  
Spatial Frequencies ◽  
Resolution Electron ◽  
Wiener Filters ◽  
Image Improvement ◽  
Optical Reconstruction ◽  
Set Up

Aposteriori deblurring of high resolution electron micrographs of weak phase objects can be performed by holographic filters [1,2] which are arranged in the Fourier domain of a light-optical reconstruction set-up. According to the diffraction efficiency and the lateral position of the grating structure, the filters permit adjustment of the amplitudes and phases of the spatial frequencies in the image which is obtained in the first diffraction order.In the case of bright field imaging with axial illumination, the Contrast Transfer Functions (CTF) are oscillating, but real. For different imageforming conditions and several signal-to-noise ratios an extensive set of Wiener-filters should be available. A simple method of producing such filters by only photographic and mechanical means will be described here.A transparent master grating with 6.25 lines/mm and 160 mm diameter was produced by a high precision computer plotter. It is photographed through a rotating mask, plotted by a standard plotter.

Rotary Beveling for In Situ Thin-Section Microscopy of Cell Cultures

1981 ◽  
Vol 39 ◽  
pp. 550-551
Author(s):  
Dean A. Handley ◽  
Jack T. Alexander ◽  
Shu Chien
Keyword(s):  
Cell Growth ◽  
Cell Cultures ◽  
Molecular Interactions ◽  
Convenient Method ◽  
Petri Dish ◽  
Simple Method ◽  
Thin Section Microscopy ◽  
Thin Sectioning ◽  
Organic Fluids

In situ preparation of cell cultures for ultrastructural investigations is a convenient method by which fixation, dehydration and embedment are carried out in the culture petri dish. The in situ method offers the advantage of preserving the native orientation of cell-cell interactions, junctional regions and overlapping configurations. In order to section after embedment, the petri dish is usually separated from the polymerized resin by either differential cryo-contraction or solvation in organic fluids. The remaining resin block must be re-embedded before sectioning. Although removal of the petri dish may not disrupt the native cellular geometry, it does sacrifice what is now recognized as an important characteristic of cell growth: cell-substratum molecular interactions. To preserve the topographic cell-substratum relationship, we developed a simple method of tapered rotary beveling to reduce the petri dish thickness to a dimension suitable for direct thin sectioning.

Development of a simple method for the determination of single nucleotide polymorphisms

2010 ◽  
Vol 34 (8) ◽  
pp. S75-S75
Author(s):  
Weifeng Zhu ◽  
Zhuoqi Liu ◽  
Daya Luo ◽  
Xinyao Wu ◽  
Fusheng Wan
Keyword(s):  
Single Nucleotide Polymorphisms ◽  
Nucleotide Polymorphisms ◽  
Simple Method ◽  
Single Nucleotide
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