TWO‐DIMENSIONAL MODELING AND ITS APPLICATION TO SEISMIC PROBLEMS

Geophysics ◽  
1960 ◽  
Vol 25 (2) ◽  
pp. 468-482 ◽  
Author(s):  
F. A. Angona
Keyword(s):  
Reflection Coefficient ◽  
Propagation Velocity ◽  
Fault Model ◽  
Curved Surfaces ◽  
Two Dimensional ◽  
Dimensional Modeling ◽  
Inverted Order ◽  
Modeling Techniques ◽  
The Difference ◽  
Thickness Variations

Laboratory seismograms of a fault model demonstrate the mechanism for diffraction and clearly show the difference in amplitude decay and moveout between a reflection and a diffraction. The inverted order and the deflection to the side of reflected energy from a curved reflector with a buried focus is demonstrated. A comparison is made of seismograms from a simple fault model and from one combining a fault with curved reflectors leading to it. The curved surfaces increase the overlap of the reflected events and mask the fault. Modeling techniques, involving the control of the reflection coefficient between layers by thickness variations and the control of the propagation velocity through a layer by combining two or more materials into a laminated sheet, are demonstrated.

REFLECTION COEFFICIENT OF AN ELECTROMAGNETIC WAVE IN CONDUCTIVE MEDIA

2018 ◽  
pp. 100-106
Author(s):  
M. S. Sudakova ◽  
M. L. Vladov ◽  
M. R. Sadurtdinov
Keyword(s):  
Reflection Coefficient ◽  
Ground Penetrating Radar ◽  
Electromagnetic Waves ◽  
Water Contamination ◽  
Survey Design ◽  
Direct And Inverse Problems ◽  
The Difference ◽  
Ground Penetrating ◽  
Ideal Dielectric

Within the ground penetrating radar bandwidth the medium is considered to be an ideal dielectric, which is not always true. Electromagnetic waves reflection coefficient conductivity dependence showed a significant role of the difference in conductivity in reflection strength. It was confirmed by physical modeling. Conductivity of geological media should be taken into account when solving direct and inverse problems, survey design planning, etc. Ground penetrating radar can be used to solve the problem of mapping of halocline or determine water contamination.

Extended two-dimensional belief function based on divergence measurement

2020 ◽  
pp. 1-8
Author(s):  
Jianping Fan ◽  
Jing Wang ◽  
Meiqin Wu
Keyword(s):  
Belief Function ◽  
Distribution Functions ◽  
Divergence Measure ◽  
Uncertain Information ◽  
Belief Functions ◽  
Two Dimensional ◽  
Probability Distribution Functions ◽  
Basic Probability ◽  
The Difference ◽  
Supporting Degree

The two-dimensional belief function (TDBF = (mA, mB)) uses a pair of ordered basic probability distribution functions to describe and process uncertain information. Among them, mB includes support degree, non-support degree and reliability unmeasured degree of mA. So it is more abundant and reasonable than the traditional discount coefficient and expresses the evaluation value of experts. However, only considering that the expert’s assessment is single and one-sided, we also need to consider the influence between the belief function itself. The difference in belief function can measure the difference between two belief functions, based on which the supporting degree, non-supporting degree and unmeasured degree of reliability of the evidence are calculated. Based on the divergence measure of belief function, this paper proposes an extended two-dimensional belief function, which can solve some evidence conflict problems and is more objective and better solve a class of problems that TDBF cannot handle. Finally, numerical examples illustrate its effectiveness and rationality.

Dilatation parameterization for two-dimensional modeling of nearly incompressible isotropic materials

2012 ◽  
Vol 57 (12) ◽  
pp. 4055-4073
Author(s):  
Hani Eskandari ◽  
Orcun Goksel ◽  
Septimiu E Salcudean ◽  
Robert Rohling
Keyword(s):  
Two Dimensional ◽  
Isotropic Materials ◽  
Dimensional Modeling

Basic determinants of epicardial transudation

1997 ◽  
Vol 273 (3) ◽  
pp. H1408-H1414 ◽  
Author(s):  
R. H. Stewart ◽  
D. A. Rohn ◽  
S. J. Allen ◽  
G. A. Laine
Keyword(s):  
Reflection Coefficient ◽  
Coronary Sinus ◽  
Myocardial Edema ◽  
Hydraulic Conductance ◽  
Linear Increase ◽  
Left Ventricular ◽  
Edema Formation ◽  
Anesthetized Dogs ◽  
The Difference ◽  
Osmotic Reflection Coefficient

Myocardial edema formation, which has been shown to compromise cardiac function, and increased epicardial transudation (pericardial effusion) have been shown to occur after elevation of myocardial venous and lymphatic outflow pressures. The purposes of this study were to estimate the hydraulic conductance and osmotic reflection coefficient for the epicardium and to determine the effect of coronary sinus hypertension and cardiac lymphatic obstruction on epicardial fluid flux (JV,e/Ae). A Plexiglas hemispheric capsule was attached to the left ventricular epicardial surface of anesthetized dogs. JV,e/Ae was determined over 30-min periods for three intracapsular pressures (-5, -15, and -25 mmHg) and two intracapsular solutions exerting colloid osmotic pressures of 7.0 and 2.0 mmHg. Hydraulic conductance was estimated to be 3.7 +/- 0.5 microliters.h-1.cm-2.mmHg-1. An osmotic reflection coefficient of 0.9 was calculated from the difference in JV,e/Ae of 16.5 +/- 8.4 microliters.h-1.cm-2 between the two solutions. Graded coronary sinus hypertension induced a linear increase in JV,e/Ae, which was significantly greater in dogs without cardiac lymphatic occlusion than in those with occlusion.

Measuring Surface Uniformity in Chemical Mechanical Polishing

2009 ◽  
Vol 76-78 ◽  
pp. 459-464
Author(s):  
Jae Won Baik ◽  
Chang Wook Kang
Keyword(s):  
Chemical Mechanical Polishing ◽  
Geometric Mean ◽  
Mechanical Polishing ◽  
Wafer Surface ◽  
Semiconductor Wafer ◽  
Statistical Process ◽  
Significant Step ◽  
The Difference ◽  
Thickness Variations ◽  
The Stability

Chemical mechanical polishing (CMP) is a technique used in semiconductor fabrication for planarizing the top surface of an in-process semiconductor wafer. Especially, Post-CMP thickness variations are known to have a severe impact on the stability of downstream processes and ultimately on device yield. Hence understanding how to quantify and characterize this non-uniformity is significant step towards statistical process control to achieve higher quality and enhanced productivity. The main reason is that the non-uniformed interface between the wafer and the machine-pad adversely affects the polishing performance and ultimate surface uniformity. The purpose of this paper is to suggest a new measure that estimates the uniformity of wafer surface considering the difference of the amount of abrasion between the center and the edge. This new measure which is called the Coefficient of Uniformity is defined as the following ratio: Geometric Mean (GM) / Arithmetic Mean (AM). This metric can be evaluated regionally to quantify the non-uniformity on the wafer surface from the center to the edge. Further simulations show that this new measure is insensitive to shift of the wafer center and sensitive to shift of the wafer edge. This trend indicates that this new measure is a very useful to test the non-uniformity of wafer after CMP polishing.

Quasi Two-Dimensional Modeling of GaN-Based MODFETs

2001 ◽  
Vol 188 (1) ◽  
pp. 251-254 ◽  
Author(s):  
F. Sacconi ◽  
A. Di Carlo ◽  
P. Lugli ◽  
H. Morko�
Keyword(s):  
Two Dimensional ◽  
Dimensional Modeling
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