The magnetotelluric impedance tensor properties with respect to rotations

Geophysics ◽  
1985 ◽  
Vol 50 (10) ◽  
pp. 1610-1617 ◽  
Author(s):  
Simon Spitz
Keyword(s):  
Data Analysis ◽  
Coordinate System ◽  
Three Dimensional ◽  
Dimensional Structure ◽  
Impedance Tensor ◽  
Coordinate Systems ◽  
Magnetotelluric Data ◽  
Conventional Analysis ◽  
Complete Set ◽  
The Relationship

A serious limitation to conventional data analysis is that the data refer mainly to elongated bodies. When three‐dimensional distortions are present, quantitative interpretation based only on the off‐diagonal elements of the conventionally rotated impedance tensor is inadequate, because these off‐diagonal elements are insensitive to the tensor trace. The impedance tensor eigenstate formulation proposed in the literature defines a complete set of parameters suitable for recognition of three‐dimensionality. Generally, though, the eigenvalues do not stand for the off‐diagonal elements of an impedance tensor measured in a physical coordinate system. It is shown how the eigenvalues are modified when the relationship between coordinate system rotations and the eigenstate formulation is clarified. A generalization of the conventional analysis results, but the rotation angle obtained is neither unique nor complete To improve the situation, two new analytical rotation angles are proposed. These angles define two complete intrinsic coordinate systems suitable for magnetotelluric data analysis when a general three‐dimensional structure is involved.

THE FORWARD MAGNETOTELLURIC PROBLEM FOR AN INHOMOGENEOUS AND ANISOTROPIC STRUCTURE

Geophysics ◽  
1974 ◽  
Vol 39 (1) ◽  
pp. 56-68 ◽  
Author(s):  
Flavian Abramovici
Keyword(s):  
Three Dimensional ◽  
Middle Layer ◽  
Conductivity Tensor ◽  
Dimensional Structure ◽  
Impedance Tensor ◽  
Variable Step Size ◽  
Step Size ◽  
Variable Step ◽  
One Step ◽  
Numerical Integration Procedure

The impedance tensor corresponding to the magnetotelluric field for a nonisotropic one‐dimensional structure is given in terms of the solutions of a sixth‐order differential system. The conductivity tensor is three‐dimensional. Its components depend upon depth only in an arbitrary manner such that the corresponding matrix is positive definite. The impedance tensor components are found by a numerical integration procedure based on a set of one‐step methods and a variable step‐size to insure a given accuracy in the final result. Calculations were made for three models having sharp boundaries and also transitional layers. The first of these models has a middle layer of high conductivity, sandwiched between two layers of linearly varying conductivity, while in the second model the middle layer has a very low conductivity. In the third model the conductivity tensor is three‐dimensional and is linearly varying in one of the layers.

DIAGRAMS FOR MAGNETOTELLURIC DATA

Geophysics ◽  
1976 ◽  
Vol 41 (4) ◽  
pp. 766-770 ◽  
Author(s):  
F. E. M. Lilley
Keyword(s):  
Impedance Tensor ◽  
Two Dimensional ◽  
Magnetotelluric Data ◽  
One Dimensional ◽  
Magnetic Components ◽  
Strike Direction ◽  
Electric And Magnetic Fields ◽  
The Relationship ◽  
Special Case ◽  
Phase Differences

Observed magnetotelluric data are often transformed to the frequency domain and expressed as the relationship [Formula: see text]where [Formula: see text] [Formula: see text] and [Formula: see text] [Formula: see text] represent electric and magnetic components measured along two orthogonal axes (in this paper, for simplicity, to be north and east, respectively). The elements [Formula: see text] comprise the magnetotelluric impedance tensor, and they are generally complex due to phase differences between the electric and magnetic fields. All quantities in equation (1) are frequency dependent. For the special case of “two‐dimensional” geology (where structure can be described as having a certain strike direction along which it does not vary), [Formula: see text] with [Formula: see text]. For the special case of “one‐dimensional” geology (where structure varies with depth only, as if horizontally layered), [Formula: see text] and [Formula: see text].

Determining the orientation of parent β grain from one α variant in titanium alloys

2018 ◽  
Vol 51 (4) ◽  
pp. 1125-1132 ◽  
Author(s):  
Z. B. Zhao ◽  
Q. J. Wang ◽  
H. Wang ◽  
J. R. Liu ◽  
R. Yang
Keyword(s):  
Titanium Alloys ◽  
Habit Plane ◽  
Electron Backscatter Diffraction ◽  
Three Dimensional ◽  
Dimensional Structure ◽  
Plane Normal ◽  
Β Phase ◽  
Microstructural Morphology ◽  
Backscatter Diffraction ◽  
The Relationship

The relationship between the crystallographic orientation and habit plane normal of transformed α laths in titanium alloys is discussed according to the Burgers orientation relationship and the three-dimensional structure of the α lath. A new method (orientation–trace method) is developed to determine the orientation of the parent β phase using the orientation of the α lath, which was measured by electron backscatter diffraction, and the microstructural morphology of that α variant. This approach is validated in a near-α titanium alloy. Moreover, the habit plane normal direction of the transformed α lath can be obtained from the crystallographic orientations of the α lath itself and its parent β grain. The verification and the corresponding discussion show the reliability of this approach.

Chinese Geodetic Coordinate System 2000 and its Comparison with WGS84

2014 ◽  
Vol 580-583 ◽  
pp. 2793-2796 ◽  
Author(s):  
Hou Pu Li ◽  
Shao Feng Bian ◽  
Zhong Mei Li
Keyword(s):  
Coordinate System ◽  
Normal Gravity ◽  
Three Dimensional ◽  
Vertical Gradient ◽  
Coordinate Systems ◽  
Present Measurement ◽  
Three Dimensional Coordinate ◽  
Geodetic Coordinate System ◽  
International Measurement ◽  
Geocentric Coordinate System

It is a general trend to adopt the geocentric coordinate system as a geodetic datum for the international measurement community. The definition and realization of Chinese geocentric three-dimensional coordinate system (CGCS2000) which has been employed since July 1st, 2008 were introduced in detail. The defining parameters and derived constants of the reference ellipsoid used were given. The comparison between CGCS2000 and WGS84 was carried out. The differences of geodetic coordinates of a point between the two coordinate systems, normal gravity and vertical gradient of normal gravity on the two ellipsoids caused by the change of the flattening of the ellipsoid were analyzed. The results show that these differences could be neglected in view of present measurement accuracies.

scholarly journals Older workers: stereotypes and occupational self-efficacy

2016 ◽  
Vol 31 (7) ◽  
pp. 1152-1166 ◽  
Author(s):  
Rita Chiesa ◽  
Stefano Toderi ◽  
Paola Dordoni ◽  
Kene Henkens ◽  
Elena Maria Fiabane ◽  
...  
Keyword(s):  
Older Workers ◽  
Self Efficacy ◽  
Age Groups ◽  
Three Dimensional ◽  
Dimensional Structure ◽  
Age Stereotypes ◽  
Content Type ◽  
Moderator Role ◽  
The Relationship ◽  
Organizational Age

Purpose The purpose of this paper is to explore the relationship between organizational age stereotypes and occupational self-efficacy. First, the authors intend to test the measurement invariance of Henkens’s (2005) age stereotypes scale across two age group, respectively, under 50 and 50 years and older. Then, the moderator role of age groups in the relationship between age stereotypes and occupational self-efficacy is investigated. Design/methodology/approach The survey involved a large sample of 4,667 Italian bank sector’s employees. Findings The results show the invariance of the three dimensional structure of organizational stereotypes towards older workers scale: productivity, reliability and adaptability. Furthermore, the moderation is confirmed: the relationship between organizational age stereotypes and occupational self-efficacy is significant only for older respondents. Research limitations/implications Future studies should aim to replicate the findings with longitudinal designs. Practical implications The study suggests the importance to emphasize the positive characteristics of older workers and to reduce the presence of negative age stereotypes in the workplace, especially in order to foster the occupational self-efficacy of older workers. Originality/value The findings are especially relevant in view of the lack of evidence about the relationship between age stereotypes and occupational self-efficacy.

scholarly journals GEODETIC REFERENCE SYSTEM TRANSFORMATIONS OF 3D ARCHIVAL GEOSPATIAL DATA USING A SINGLE SSC TERRASAR-X IMAGE

2016 ◽  
Vol XLI-B1 ◽  
pp. 1207-1212
Author(s):  
D. I. Vassilaki ◽  
A. A. Stamos
Keyword(s):  
Coordinate System ◽  
Real World ◽  
Reference System ◽  
Absolute Error ◽  
Geospatial Data ◽  
Geodetic Reference System ◽  
Coordinate Systems ◽  
3D Information ◽  
The Relationship ◽  
Geolocation Accuracy

Many older maps were created using reference coordinate systems which are no longer available, either because no information to a datum was taken in the first place or the reference system is forgotten. In other cases the relationship between the map’s coordinate system is not known with precision, meaning that its absolute error is much larger than its relative error. In this paper the georeferencing of medium-scale maps is computed using a single TerraSAR-X image. A single TerraSAR-X image has high geolocation accuracy but it has no 3D information. The map, however, provides the missing 3D information, and thus it is possible to compute the georeferencing of the map using the TerraSAR-X geolocation information, assembling the information of both sources to produce 3D points in the reference system of the TerraSAR-X image. Two methods based on this concept are proposed. The methods are tested with real world examples and the results are promising for further research.

The 3-D Structure of Swirl-Stabilized Flames in a Lean Premixed Multi-Nozzle Can Combustor

2015 ◽  
Author(s):  
Janith Samarasinghe ◽  
Stephen J. Peluso ◽  
Bryan D. Quay ◽  
Domenic A. Santavicca
Keyword(s):  
Gas Turbine ◽  
Tomographic Reconstruction ◽  
Flame Structure ◽  
Combustion Process ◽  
Three Dimensional ◽  
Static Stability ◽  
Dimensional Structure ◽  
Reconstruction Technique ◽  
Flame Stability ◽  
The Relationship

Flame structure is an important aspect of the combustion process which must be considered in the design of gas turbine combustors as it can have a significant effect on the combustor’s static stability (blowoff) and dynamic stability (combustion instability). The relationship between flame structure and flame stability has been studied extensively in single-nozzle combustors. However, relatively few studies have been conducted in multi-nozzle combustor configurations typical of actual gas turbine combustion systems. In this paper, a chemiluminescence-based tomographic reconstruction technique is used to obtain three-dimensional images of the flame structure in a laboratory-scale five-nozzle can combustor. The images reveal the complex three-dimensional structure of this multi-nozzle flame, as well as, the effects of interacting swirling flows, flame-flame interactions and flame-wall interactions on flame structure.

Mapping of monoclonal antibodies specific to P64k: A common antigen of several isolates of Neisseria meningitidis

2001 ◽  
Vol 47 (2) ◽  
pp. 158-164 ◽  
Author(s):  
C Nazábal ◽  
T Carmenate ◽  
S Cruz ◽  
S González ◽  
R Silva ◽  
...  
Keyword(s):  
Monoclonal Antibodies ◽  
Neisseria Meningitidis ◽  
Three Dimensional ◽  
Structural Data ◽  
Dimensional Structure ◽  
Bacterial Surface ◽  
A Minor ◽  
The Relationship ◽  
Cell Elisa ◽  
Competition Assays

P64k is a minor outer membrane protein from Neisseria meningitidis. This protein has been produced at high levels in Escherichia coli. We generated a group of monoclonal antibodies (mAbs) against recombinant P64k, which recognise four non-overlapping epitopes, as shown using competition assays with biotinylated mAbs. The P64k sequences involved in mAbs binding were mapped with synthetic overlapping peptides derived from the P64k protein, and located in the previously determined three-dimensional structure of the protein. These antibodies were also characterised by whole-cell ELISA and bactericidal tests against N. meningitidis. Only two of the recognised epitopes were exposed on the bacterial surface, and none of the mAbs showed bactericidal activity. The relationship between these results and the structural data on the epitopes bound by the mAbs is discussed.Key words: Neisseria meningitidis, P64k, monoclonal antibodies, epitope mapping.

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