Full field apparent resistivity definition of Borehole TEM with electric source

Background Appropriate mammary positioning is an important factor in optimizing image quality in mammography (MMG). Purpose To study the correlation of quality criteria and breast density classification proposed by the American College of Radiology (ACR) and European Guidelines and its influence to achieve a proper positioning, therefore an adequate MMG. Material and methods A total of 128 routine MMG examinations were reviewed for the definition of breast composition parenchyma and assessment of several quality criteria proposed by the ACR and European Guidelines to achieve an adequate MMG. Adequate MMG was defined as a difference between the posterior nipple line (PNL), difference of the mediolateral oblique (MLO) and craniocaudal (CC) incidences > 1 cm. The quality criteria were analyzed as a function of correlation coefficient in order to evaluate the individual impact of each factor and analysis of variance (ANOVA) for all criteria. Receiver operating characteristic (ROC) curves were plotted to evaluate the performance of the criteria on each type of parenchyma. Results Negative correlation of fatty breasts and visibility of the mammary angle, a greater number of skin folds and PNL > 1 cm (r < 0). Dense MMG presented less visibility of the lateral tissue compared with other categories. Area under the curve of ROC analysis revealed values of 53.1% and 54.7% for the right and left breasts, respectively. Conclusion Several factors influenced in the MMG process, but we find that breast parenchyma has a substantial role in affecting these criteria and therefore a correct position for diagnosis, which could compromise MMG diagnostic performance.

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Reservoir to market: generating project value by coupling surface facilities with reservoir data in integrated asset modelling

The APPEA Journal ◽

10.1071/aj16216 ◽

2017 ◽

Vol 57 (2) ◽

pp. 652

Author(s):

Stephen Stokes

Keyword(s):

Supply Chain ◽

Development Planning ◽

Cutting Edge ◽

Concept Design ◽

Full Spectrum ◽

Full Field ◽

Field Development ◽

Cost Reductions ◽

Definition Of ◽

Assessing Sensitivity

Reservoir to market is a cutting-edge integrated asset modelling (IAM) initiative that is deployed to deliver robust field development and concept design solutions with enhanced project economics. The approach offers the potential to identify supply-chain cost reductions across the full spectrum of upstream developments, from full field development planning to individual equipment item modification. The process offers particular value in Greenfield and Brownfield development planning, in identifying and assessing sensitivity options and in definition of the optimum concept.

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Full Zone Apparent Resistivity Definition of Semi-airborne Transient Electromagnetic Method

10.1190/nsgapc2013-097 ◽

2013 ◽

Cited By ~ 2

Author(s):

Ying-ying Zhang ◽

Xiu Li ◽

Zhi-peng Qi

Keyword(s):

Apparent Resistivity ◽

Electromagnetic Method ◽

Transient Electromagnetic Method ◽

Transient Electromagnetic ◽

Definition Of

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What is the depth of investigation of a resistivity measurement?

Geophysics ◽

10.1190/geo2013-0261.1 ◽

2014 ◽

Vol 79 (2) ◽

pp. W1-W10 ◽

Cited By ~ 4

Author(s):

Enrique Gómez-Treviño ◽

Francisco J. Esparza

Keyword(s):

Apparent Resistivity ◽

Resistivity Measurement ◽

Weighted Average ◽

Sensitivity Function ◽

Resistivity Sounding ◽

Practical Applications ◽

Resistivity Profile ◽

Definition Of ◽

Homogeneous Media ◽

Depth Of Investigation

Ever since the first computation of resistivity sounding curves, there has been the impression that somehow they are averages of the vertical resistivity profile. This prompted the idea to represent apparent resistivity as an integral over depth and to define depth of investigation using the integrands of the integrals as elementary contributions. However, elementary contributions for a boundary value problem cannot be uniquely defined and are not physically meaningful. Many practical applications that have been derived from this approach might be at stake regarding their theoretical basis. On the other hand, a sensitivity function has a definite physical meaning and it is uniquely defined, but it offers a different picture for a layered earth. The concept of elementary contributions must then be abandoned as not real, as some respected scholars have suggested, or it must be put on solid ground if we are going to continue using it. Our claim is that any definition of elementary contributions must comply with the concept of sensitivity; otherwise, it must be discarded not because it might be proved wrong, but because we cannot have multiple functions pretending to represent the depth of investigation of a resistivity measurement. We determined that both concepts can be unified and reconciled into a single formulation. That is, one and the same function of depth can be interpreted as an elementary contribution or as the local sensitivity. To further support the effectiveness of the concept, we applied it beyond its traditional application to homogeneous media. We developed an approximate formula for computing apparent resistivity as a weighted average of the vertical resistivity profile. The formula works in the way of a toy model; it is an approximation, but it provides immediate insights into how a vertical resistivity profile relates to its sounding curve.

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The ratio apparent resistivity definition of rectangular-loop TEM

Journal of Applied Geophysics ◽

10.1016/j.jappgeo.2014.01.015 ◽

2014 ◽

Vol 103 ◽

pp. 152-160 ◽

Cited By ~ 9

Author(s):

NanNan Zhou ◽

GuoQiang Xue

Keyword(s):

Apparent Resistivity ◽

Definition Of

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Strapdown Optical Seeker Guidance Instructions Extraction and System Stability

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.397-400.1357 ◽

2013 ◽

Vol 397-400 ◽

pp. 1357-1361

Author(s):

Yue Zhang

Keyword(s):

Optical Imaging ◽

Angular Rate ◽

Extraction Methods ◽

Stability Control ◽

Scale Factor ◽

System Stability ◽

Line Of Sight ◽

Full Field ◽

Free Running ◽

Definition Of

In order to realize the guidance and control of the flight system, we focused on the study of different guidance instructions extraction methods and system stability control problems with respect to the characteristics of full-strapdown optical imaging seeker. First, we established the model of strapdown optical imaging seeker and introduced the definition of scale factor and the theoretical compute formula. Then the full field of view accuracy of full-strapdown optical imaging seeker was gained through the experiment and the validity of the scale factor definition has been tested and verified. Finally, we analyzed the system stabilities of different guidance instructions extraction methods. The results showed that if we applied the line of sight angular rate (LOS angular rate) to the system, the scale factor error was 5% when the free-running frequency of the overload autopilot was 20rad/s, and the scale factor error was 8.4% when the free-running frequency was 10rad/s. And if we applied the line of sight angle (LOS angle) to the system, the scale factor error was 33.3%, irrelevant to the free-running frequency. This analysis laid a foundation of guidance application..

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The Development of a Reference Material for Calibration of Full-Field Optical Measurement Systems for Dynamic Deformation Measurements

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.70.33 ◽

2011 ◽

Vol 70 ◽

pp. 33-38 ◽

Cited By ~ 5

Author(s):

Andrea Davighi ◽

Richard L. Burguete ◽

Mara Feligiotti ◽

Erwin Hack ◽

Simon James ◽

...

Keyword(s):

Reference Material ◽

Optical Measurement ◽

Three Dimensional ◽

Speckle Interferometry ◽

Optical Systems ◽

Measured Quantity ◽

Full Field ◽

Measurement Systems ◽

Definition Of ◽

Generic Design

A reference material is defined as material, sufficiently homogeneous and stable with respect to one or more specified properties, which has been established to be fit for its intended use in a measurement process. Reference materials provide a simple definition of the measured quantity that can be traced to an international standard and can be used to assess the uncertainty associated with a measurement system. Previous work established a reference material and procedure for calibrating full-field optical systems suitable for measuring static, in-plane strain distributions. Efforts are now underway to extend this work to the calibration of systems capable of measuring three-dimensional deformation fields induced by dynamic loading. The important attributes for a dynamic reference material have been identified in a systematic and rational fashion, which have been subsequently translated into a generic design specification. Initial prototypes of candidate designs have been produced and evaluated using experimental modal analysis and digital speckle interferometry, and the results have been compared with finite element analyses. Based on the outcome of this initial evaluation, further refinements in design and manufacturing are proposed.

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The Definition of Apparent Resistivity in Magnetotelluric Sounding

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.962-965.189 ◽

2014 ◽

Vol 962-965 ◽

pp. 189-192

Author(s):

Bao Sheng Huang ◽

Guo Xiang Yan

Keyword(s):

Theoretical Calculation ◽

Model Calculation ◽

Imaginary Part ◽

Apparent Resistivity ◽

Calculation Formula ◽

Practical Application ◽

The Real ◽

Calculation Results ◽

Definition Of ◽

Different Characteristics

Different apparent resistivity exists many different characteristics, such as in terms of the speed of tending to real resistivity, the strength of oscillation sexual and the resolution. Aimed at the problem of how to select apparent resistivity in magnetotelluric (MT), this paper compares and analyzes the characteristics of different apparent resistivity in reflecting underground electrical structure by theoretical calculation formula and model calculation, and then summarizes the advantage and disadvantage of different apparent resistivity. The calculation results of several typical geoelectric models show that Basukur apparent resistivity is the best definition method of apparent resistivity, followed in turn, from good to bad, is the apparent resistivity defined by the real part of impedance, discount apparent resistivity, Cagniard apparent resistivity and the apparent resistivity defined by the impedance square module and the apparent resistivity defined by the imaginary part of impedance square, and the apparent resistivity defined by the imaginary part of impedance is the worst. this conclusions provide the judgment basis for practical application.

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Multiseparation, multisystem electromagnetic depth sounding‐An extension for unification

Geophysics ◽

10.1190/1.1444145 ◽

1997 ◽

Vol 62 (1) ◽

pp. 56-62 ◽

Cited By ~ 5

Author(s):

Umesh C. Das

Keyword(s):

Apparent Resistivity ◽

Mutual Coupling ◽

Random Noise ◽

Field Measurements ◽

Dipole Source ◽

Controlled Source ◽

Definition Of ◽

Depth Sounding ◽

Central Loop ◽

The Given

A recent definition of controlled‐source electromagnetic apparent resistivity has been adopted, and it is shown that this definition is unique. It produces a single apparent resistivity value by transforming any of the given combinations of the mutual coupling ratios measured by five different source‐receiver configurations, namely, horizontal coplanar loops (HCP), vertical coplanar loops (VCP), vertical coaxial loops (VCA), electric dipole source and horizontal receiver loop (EDL), and central loop (in‐loop) configurations. Synthetic field data for the commercially available MaxMin system, which can be operated with HCP, VCP, and VCA configurations, are fabricated and they are transformed to apparent resistivities. An analysis of apparent resistivity curves so obtained reveals the requirements of the ranges of frequencies and transmitter‐receiver separations needed for given exploration depth. A concise analysis of the effect of the random noise errors in the MaxMin data on stability of apparent resistivity is carried out. From this analysis, it is expected that apparent resistivities from field measurements will be stable, even when the measurements are corrupted with random noises.

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