AN APPROXIMATE CORRECTION METHOD FOR REFRACTION IN REFLECTION SEISMIC PROSPECTING

Geophysics ◽  
1951 ◽  
Vol 16 (3) ◽  
pp. 468-485 ◽  
Author(s):  
Th. Krey
Keyword(s):  
Average Velocity ◽  
Correction Method ◽  
Image Point ◽  
Seismic Prospecting ◽  
Reflection Seismic ◽  
Seismic Image

Equations are derived and discussed to compute approximate corrections which must be applied to the results obtained by the classical methods of computing and constructing data in reflection seismic prospecting, (this includes the method of construction of seismic image point and the method of seismic prospecting using zero‐spread time) to correct for refraction. In addition, the influence of refraction on the determination of average velocity as obtained by applying the time‐square distance‐square curve (Time‐Delta‐Time Velocity) is analyzed.

Analysis of STEM micrographs of thick objects

1978 ◽  
Vol 36 (2) ◽  
pp. 106-107
Author(s):  
S. Golladay
Keyword(s):  
Inelastic Scattering ◽  
Multiple Scattering ◽  
Mass Distribution ◽  
Cross Sections ◽  
Phase Contrast ◽  
Image Point ◽  
Contrast Effects ◽  
Total Cross Sections ◽  
Elastic And Inelastic Scattering

The theory of multiple scattering has been worked out by Groves and comparisons have been made between predicted and observed signals for thick specimens observed in a STEM under conditions where phase contrast effects are unimportant. Independent measurements of the collection efficiencies of the two STEM detectors, calculations of the ratio σe/σi = R, where σe, σi are the total cross sections for elastic and inelastic scattering respectively, and a model of the unknown mass distribution are needed for these comparisons. In this paper an extension of this work will be described which allows the determination of the required efficiencies, R, and the unknown mass distribution from the data without additional measurements or models. Essential to the analysis is the fact that in a STEM two or more signal measurements can be made simultaneously at each image point.

scholarly journals Comparison of different models to calculate the viscosity of biogas and biomethane in order to accurately measure flow rates for conformity assessment

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Karine Arrhenius ◽  
Oliver Büker
Keyword(s):  
Binary Mixtures ◽  
Flow Rate ◽  
Correction Method ◽  
Gas Mixtures ◽  
Conformity Assessment ◽  
Flow Rates ◽  
Unknown Composition

AbstractThe study presents an optimised method to correct flow rates measured with a LFE flowmeter pre-set on methane while used for gas mixtures of unknown composition at the time of the measurement. The method requires the correction of the flow rate using a factor based on the viscosity of the gas mixtures once the composition is accurately known. The method has several different possible applications inclusive for the sampling of biogas and biomethane onto sorbent tubes for conformity assessment for the determination of siloxanes, terpenes and VOC in general. Five models for the calculation of the viscosity of the gas mixtures were compared and the models were used for ten binary mixtures and four multi-component mixtures. The results of the evaluation of the different models showed that the correction method using the viscosity of the mixtures calculated with the model of Reichenberg and Carr showed the smallest biases for binary mixtures. For multi-component mixtures, the best results were obtained when using the models of Lucas and Carr.

On Improving the Performances of Hydraulic Incremental Positioning Units with Mechanical Position Feedback

2012 ◽  
Vol 463-464 ◽  
pp. 1277-1280 ◽  
Author(s):  
Constantin Bucşan ◽  
Mihai Avram
Keyword(s):  
Real Time ◽  
Correction Method ◽  
Practical Application ◽  
Positioning Accuracy ◽  
Positioning Systems ◽  
Sensing System ◽  
Position Feedback ◽  
Time Determination ◽  
Interesting Solution

This paper presents a method for increasing the speed and the positioning accuracy of the positioning systems with mechanical position feedback. The method consists in using a position transducer for real time determination of the position of the load and correcting this position using an adequate algorithm. It is preferable not to modify the construction of the positioning unit, allowing the user to decide when to use this correction method according to the practical application. An interesting solution to this problem is to use an external space-position finding sensing system, as presented in the paper.

Experimental Determination of Side Boundary Effects on Stress Intensity Factors in Surface Flaws

1975 ◽  
Vol 97 (1) ◽  
pp. 45-51 ◽  
Author(s):  
M. Jolles ◽  
J. J. McGowan ◽  
C. W. Smith
Keyword(s):  
Stress Intensity ◽  
Crack Length ◽  
Taylor Series ◽  
Stress Intensity Factors ◽  
Taylor Series Expansion ◽  
Correction Method ◽  
Intensity Factors ◽  
Surface Flaws ◽  
Plate Width

A technique consisting of stress-freezing photoelasticity coupled with a Taylor Series Expansion of the maximum local in-plane shearing stress known as the Taylor Series Correction Method (TSCM) is applied to the determination of stress intensity factors (SIF’s) in flat bottomed surface flaws of flaw depth/length ratios of approximately 0.033. Flaw depth/thickness ratios of approximately 0.20 and 0.40 were studied as were plate width/crack length ratios of approximately 2.33 and 1.25, the former of which corresponded to a nearly infinite width. Agreement to well within 10 percent was found with the Rice-Levy and Newman theories using a depth-modified secant correction and equivalent flaw depth/length ratios. The Shah-Kobayashi Theory, when compared on the same basis, was lower than the experimental results. Using a modified net section stress correction suggested by Shah, agreement with the Shah-Kobayashi Theory was greatly improved but agreement with the other theories was poorer. On the basis of the experiments alone, it was found that the SIF was intensified by about 10 percent by decreasing the plate width/crack length from 2.33 to 1.25.

THREE‐DIMENSIONAL SEISMIC METHOD

Geophysics ◽  
1972 ◽  
Vol 37 (3) ◽  
pp. 417-430 ◽  
Author(s):  
G. G. Walton
Keyword(s):  
Seismic Data ◽  
Average Velocity ◽  
Three Dimensional ◽  
Data Gathering ◽  
Seismic Method ◽  
Dynamic Display ◽  
Profile Line ◽  
Production Problems ◽  
Dense Coverage

The three‐dimensional seismic method is a different way of gathering and presenting seismic data. Instead of showing the subsurface beneath a profile line, 3-D displays give an, areal picture from the shallowest reflector to the deepest one that can be found seismically. Data are collected in the field with cross‐spreads that provide over 2000 evenly spaced depth points on each reflecting interface. Several variations of the cross‐spread technique give the same subsurface coverage while providing flexibility in data gathering. Because of the dense coverage, the method is best suited for problems requiring great detail, such as production problems. The usual presentation of 3-D data is a visual, moving display of emerging wavefronts covering four sq mi of surface. From this dynamic display, average velocity to each reflector and the dip direction and magnitude can be computed. The method has proved especially useful for the recognition of faults and determination of fault directions.

SEL VƏ DAŞQIN AXINLARINDA DAĞ ÇAYLARI MƏCRASININ YUYULMA DƏRİNLİYİNİN TƏYİNİ

2021 ◽  
Vol 1 (1) ◽  
pp. 82-88
Author(s):  
F.Ş., Əhmədov ◽  
R.K., Quliyev ◽  
R.Ü Əbdüləzimov
Keyword(s):  
Average Velocity ◽  
Average Diameter ◽  
Average Depth ◽  
Mountain River ◽  
Mountain Rivers ◽  
Cross Sectional ◽  
Average Width ◽  
Caucasus Mountains ◽  
Flood Flow

Abstract. The article is dedicated to the determination of the wash depth of mountain rivers in floods and overflows. As well-known, hydrotechnical equipment is exposed to destructive damages of the floods and overflows. The undersurface of bridge basement and coast guards are washed away, the surface of drainage devices in water supply and dams (Düker) at river crossings are opened up. Therefore, the protection of the equipment against the destructive damage of the floods and overflows should be ensured. To this aim, first of all, the depth of the fortification of the equipment basement in riverbeds and the width through which the river can flow should be determined and the works of installing coast guards should be accordingly implemented. Since the flow regime of rivers due to floods in the course of mountain riverbeds dramatically changes, the width, depth, roughness and cross-sectional area of the riverbed also changes. To that reason, in the smallest case, calculation formulas includes the average width and wash depth of the riverbed in the course of the floods and overflows, average diameter of undersurface soils, the slope of the location of hydrotechnical structures, velocity due to the average diameter of the riverbed soils and so on. The article contains the analyses of theoretical and practical materials about the floods and overflows in mountain rivers. For the rivers flowing through the southern hills of Great Caucasus Mountains, the expressions for determining the riverbed parameters and hydrological parameters of rivers are used. According to the expressions, average width due to non-washing of the riverbed in floods in accordance with flood flow and slope of the studied part of the riverbed, the average depth of the riverbed crossing the flood, the average velocity of the flow and the wash depth in accordance with them are determined. basing on all these, the determining method of the wash depth of mountain riverbeds in floods have been worked out and determining the wash depth have been recorded. The studied methodology can be used in determining the riverbed parameters in floods and overflows. Keywords: Flood, riverbed deformation, mountain river, wash depth, average diameter of undersurface sediments, riverbed stability, flood velocity

scholarly journals Absorbance Correction Method for Simultaneous Estimation of Nifedipine and Metoprolol Succinate in Their Synthetic Mixture Using From Spectrophotometry

2015 ◽  
Vol 1 (3) ◽  
pp. 151
Author(s):  
Sojitra Rajanit ◽  
Paras Virani ◽  
Hashumati Raj
Keyword(s):  
Accurate Method ◽  
Correction Method ◽  
Synthetic Mixture ◽  
Simultaneous Estimation ◽  
Metoprolol Succinate ◽  
Absorption Correction ◽  
Ich Guidelines ◽  
Development And Validation ◽  
Tablet Dosage

A new simple, economical, precise and accurate method are described for the simultaneous determination of Nifedipine (NIF) and Metoprolol Succinate (MET) in combined tablet dosage form. The proposed method was applied for the determination of Nifedipine and Metoprolol Succinate in synthetic mixture, for determination of sampling wavelength, 10?g/ml of each of NIF and MET were scanned in 200-400 nm range and sampling wavelengths were 313nm for NIF and 275.40nm for MET are selected for development and validation of absorption correction method. For this method linearity observed in the range of 5-25?g/ml for NIF and 25-125?g/ml for MET, and in their pharmaceutical formulation with mean percentage recoveries 100.68 and 100.33, respectively. The method was validated according to ICH guidelines and can be applied for routine quality control testing.

Determination of an image point on a surface based on a $$\pi $$ π plane-based algorithm

2013 ◽  
Vol 53 (5) ◽  
pp. 1033-1046 ◽  
Author(s):  
Sang Inn Woo ◽  
Rodrigo Salgado
Keyword(s):  
Image Point
Sign in / Sign up

Export Citation Format

Share Document