AN EXPLANATION OF OBSERVED TIME DISCREPANCIES BETWEEN CONTINUOUS AND CONVENTIONAL WELL VELOCITY SURVEYS

Geophysics ◽  
1971 ◽  
Vol 36 (2) ◽  
pp. 285-295 ◽  
Author(s):  
E. Strick
Keyword(s):  
Mathematical Model ◽  
Seismic Energy ◽  
Attenuation Function ◽  
Linear Frequency ◽  
The Earth ◽  
Statistical Time ◽  
Predicted Values ◽  
Logging Tool ◽  
Q Values ◽  
40 Hz

Equations derived from the author’s mathematical (PL) model for the absorption of seismic energy by the earth are applied to explain statistical time discrepancies observed by Gretner between measurements using a continuous (CV) logging tool and conventional check shots. In essence, the predicted discrepancy is due to the pedestal effect that the author has fully described in an earlier paper. The magnitude of the predicted discrepancy not only agrees extremely well with the statistical observations but the corresponding theoretical Q’s for rock that are necessary to cause just such deviations are quite consistent with Q values expected in the shales and sandstones in which the observations were made. Our interpretation is also consistent with Gretner’s observation that the discrepancies are independent of the measured velocities. It is also shown that a mathematical model (TLF) based upon a truncation of a linear frequency attenuation function predicts time discrepancies just about as well as does the PL model but that the predicted values of Q at 40 hz are 60 percent larger. However, ambiguities still remain and the use of the TLF model is not recommended.

scholarly journals Possibilities of improving the TD88 atmospheric total density model

2010 ◽  
pp. 57-61
Author(s):  
S. Segan ◽  
D. Marceta
Keyword(s):  
Mathematical Model ◽  
Control Model ◽  
Density Model ◽  
Total Density ◽  
Polyharmonic Function ◽  
The Earth ◽  
The Mathematical Model

In this paper we have examined possibilities for preserving and improving the total density model of the Earth?s neutral thermosphere TD88 (Sehnal and Posp?silov? 1988) via modelling differences between TD88 and NRLMSISE-00 (Picone et al. 2002), which is used as a control model. It is shown that these residuals can be approximated with polyharmonic function. Starting from this we have developed the mathematical model of the residuals to identify their origin and possibilities to improve the TD88 model itself.

scholarly journals Global earthquakes in the 2020 second half according to the GS RAS

2021 ◽  
Vol 3 (1) ◽  
pp. 7-26
Author(s):  
Yuri Vinogradov ◽  
Mariya Ryzhikova ◽  
Natalia Petrov ◽  
Svetlana Poygina ◽  
Marina Kolomiets
Keyword(s):  
Seismic Energy ◽  
Aegean Sea ◽  
Focal Mechanisms ◽  
Intraplate Earthquake ◽  
Strong Earthquakes ◽  
Tatar Strait ◽  
The Earth ◽  
Deformation Processes ◽  
The Russian Federation ◽  
Deep Focus

The data on the seismicity of the Earth in the second half of 2020 at the level of strong earthquakes with magnitudes mb≥6.0 are given according to the data of the Alert Service of the Geophysical Survey RAS. The review also includes information on 54 tangible earthquakes in Russia and five earthquakes in adjacent territories that were felt in the settlements of the Russian Federation. Two of 67 strong earthquakes of the Earth with mb≥6.0 for the period under consideration were registered in the territory of Russia. For 15 strong earthquakes, the Alert Service published Information Messages within one or two days after their occurrence, for 14 earthquakes the information on focal mechanisms is provided. The strongest earthquake of the Earth with MS=7.9 occurred on July, 22 in the region of the Alaska Peninsula. The maximum human casualties and material damage during the study period were the result of the catastrophic intraplate earthquake with MS=6.8, which occurred on October, 30 in the Aegean Sea, near the Samos Island. As a result of the earthquake, 117 people died, 1054 were injured. The strongest earthquake on the territory of Russia was the deep-focus one with mb=6.4, which took place on November, 30 in the Tatar Strait, separating Sakhalin Island from continental Eurasia. The crustal Bystrinsk earthquake on September, 21 with MS=5.2, which occurred in the area of Lake Baikal, was felt with a maximum intensity I=6–7 on the territory of Russia. Comparative analysis of the rate of seismic energy released in the Globe in 2010-2020 showed that its value in the second half of 2020, as well as for 2019-2020 on average, is one of the lowest for the eleven-year period and indicates a seismic calm, which should be replaced by a period of intensification of global seismic and deformation processes

scholarly journals Mathematical Models and Evaluation Software for Stress-Strain State of the Earth’s Lithosphere

2019 ◽  
pp. 51-66
Author(s):  
Alexander O. Faddeev ◽  
Svetlana A. Pavlova ◽  
Tatiana M. Nevdakh
Keyword(s):  
Mathematical Model ◽  
Strain State ◽  
Uniform Grid ◽  
Shear Stresses ◽  
Stress Strain ◽  
Gravitation Field ◽  
Vertical Movements ◽  
Stress Strain State ◽  
The Earth ◽  
Viscous Shear

Introduction. For the purposes of this article, geodeformation processes mean processes associated with deformations arising from the movement of species and blocks of the lithosphere at various depths, including surfaces. The objective is to reconstruct geodynamic stress fields, which cause modern shifts and deformations in the Lithosphere. A mathematical model and software for estimating the stress-strain state of the Earth Lithosphere are considered. Materials and Methods.For mathematical modeling of stresses, isostatically reduced data on abnormal gravitation field were used. The methods of continuum mechanics and methods of the theory of differential equations were used to design a model for estimating the stressstrain state of the Earth Lithosphere. For processing input, intermediate and outcoming data, the Fourier transform method of spectral analysis for constructing grid functions and spectral-temporal method were used. To model for the stress-strain state of the Lithosphere globally, stress calculation was corrected on the basis of sputnik-derived velocity data at the surface of the earth crust. The data on the rates of horizontal and vertical movements at the surface of the Earth crust were processed to obtain a distribution of velocities in the uniform grid embracing longitudes and latitudes. The processing procedure was carried out on the basis of the Kraiging method. The software was developed in Borland Delphi 7.0 programming environment. Results. Based on the data on the abnormal gravitation field in isostatic reduction and information on the distribution of velocities of horizontal motions on the surface of the Earth crust, a mathematical model of the stress-strain state of the Lithosphere was constructed. With the help of the obtained mathematical model and software complex, the stress-strain state of the Lithosphere was calculated at various depth using elastic and elastic-viscous models, and maps of equipotential distribution of shear elastic-viscous deformations in the lithosphere at the depth of 10 km were constructed. Discussion and Conclusion. The presented mathematical model and software allow restoring fields of both elastic and elastic-viscous deformations that is fundamental for quantification of elastic-viscous shear stresses deep in the Earth Lithosphere.

Contributions to a Future Inertial Motor and More

2013 ◽  
Vol 4 (1) ◽  
pp. 63-97 ◽  
Author(s):  
Dan Ciulin
Keyword(s):  
Mathematical Model ◽  
Gravitational Waves ◽  
Euler Equations ◽  
Electronic Devices ◽  
Trigonometric Functions ◽  
Jet Engines ◽  
Comprehensive Understanding ◽  
Life Conditions ◽  
Lifting Force ◽  
The Earth

For a future interplanetary trip, a space ship must be able to take off and/or land on a planet and travel at a convenient speed, insure convenient life conditions for the embarked crew, and keep contact with Earth. Chemical jet-engines used for the space ships must throw masses with enough speed to insure a convenient lifting force. Ion jet-engines, which have a much bigger jet-speed than chemical, may work for a longer time but the resulting force is small and cannot insure the take off and/or landing on a planet. A future inertial motor does not need to throw masses but needs only energy to produce the necessary lifting force. The paper presents contributions to build such a motor. As on a given vehicle, mainly rotations may be done to insure its propulsion, we start by presenting generally the rotations, at first for the electronic devices and then for mechanical one Methods that may convert the rotation into translation are after presented. Observing that the mathematical models used for rotations are extended from trigonometric functions to elliptical and ultra-elliptical ones, the author presents the differential equations that define such functions. Finally, using the modified Euler equations, a mathematical model for the gravitational waves is deduced. By using this type of waves, a permanent contact between an interplanetary ship and the earth can be kept. The presented tools may be used for modeling the fields and insure also a more comprehensive understanding.

scholarly journals A Model of Brain Arteriolar Oxygen and Carbon Dioxide Transport during Anemia

1993 ◽  
Vol 13 (5) ◽  
pp. 872-880 ◽  
Author(s):  
Richard S. Schacterle ◽  
Robert J. Ribando ◽  
J. Milton Adams
Keyword(s):  
Carbon Dioxide ◽  
Mathematical Model ◽  
Blood Flow ◽  
Tissue Oxygenation ◽  
Normal Values ◽  
Experimental Studies ◽  
Limited Information ◽  
Carbon Dioxide Transport ◽  
Theoretical Evidence ◽  
Predicted Values

Existing experimental and theoretical evidence suggests that precapillary diffusion of O2 and CO2 occurs between arterioles and tissue under normal physiologic conditions. However, limited information is available on arteriolar gas transport during anemia. With use of a mathematical model of an arteriolar network in brain tissue, anemic hematocrits of 35, 25, and 15% were modeled to determine the effect of anemia on the exchange, the change in the equilibrium tissue O2 and CO2 tensions, and the increase in blood flow needed to restore tissue oxygenation. We found that the blood Po2 exiting the network fell from 66 mm Hg normally to 48 mm Hg during the severest anemia. Concurrently, the equilibrium tissue O2 tensions dropped from 44 to 23 mm Hg. For CO2 the exit blood Pco2 was 58 mm Hg for a 15% hematocrit, an increase of 4 mm Hg from the normal value, and equilibrium tissue Pco2 increased from 56 to 61 mm Hg. Blood flow increases from normal values necessary to offset the effects of the decreased O2 delivery to the tissue were 26, 86, and 222%, respectively, for hematocrits of 35, 25, and 15%. We compared our model results with recent experimental studies that have suggested that the amount of O2 diffusion is much higher than predicted values. We found that these experimental O2 gradients are three to four times larger than theoretical.

Examination of α-decay half-lives of undetected transfermium isotopes

2020 ◽  
Vol 29 (10) ◽  
pp. 2050085
Author(s):  
Nguyen Nhu Le ◽  
Nguyen Ngoc Duy
Keyword(s):  
Half Life ◽  
Spontaneous Fission ◽  
Theoretical Calculations ◽  
Q Value ◽  
Calculation Methods ◽  
Α Decay ◽  
Decay Modes ◽  
Predicted Values ◽  
Semi Empirical ◽  
Q Values

This study reports the [Formula: see text]-decay half-lives of 39 transfermium isotopes with [Formula: see text], most of which have not been observed. The half-lives were calculated using micro–macroscopic approaches and semi-empirical formulae, applying current [Formula: see text]-decay Q-values from the latest mass database, AME2016. These results were compared to predicted values in previous works to evaluate the efficiency of and difference between various calculation methods. We found that the [Formula: see text]-resonance approach used in a previous study is not appropriate to predict though most other approaches are mutually consistent. An uncertainty of 70% was observed in the present theoretical calculations, similar to that observed in measurements. A Q-value uncertainty of 10% can lead to a large variation of 3 orders of magnitude in predicted [Formula: see text]-decay half-life. We also found that the dominance of either [Formula: see text] decay or spontaneous fission is unclear for the isotopes with [Formula: see text]–[Formula: see text], whereas most of the nuclei of [Formula: see text]–[Formula: see text] can be clearly identified as [Formula: see text] emitters. Finally, we provide the updated [Formula: see text]-decay half-lives for the isotopes of interest, including their uncertainties and corresponding decay modes.

Nonlinear waves in compacting media

1986 ◽  
Vol 164 ◽  
pp. 429-448 ◽  
Author(s):  
Victor Barcilon ◽  
Frank M. Richter
Keyword(s):  
Mathematical Model ◽  
Solitary Waves ◽  
Nonlinear Waves ◽  
Nonlinear Interaction ◽  
Phase Speed ◽  
Governing Equations ◽  
One Dimensional ◽  
The Earth ◽  
Permanent Shape ◽  
The Mathematical Model

An investigation of the mathematical model of a compacting medium proposed by McKenzie (1984) for the purpose of understanding the migration and segregation of melts in the Earth is presented. The numerical observation that the governing equations admit solutions in the form of nonlinear one-dimensional waves of permanent shape is confirmed analytically. The properties of these solitary waves are presented, namely phase speed as a function of melt content, nonlinear interaction and conservation quantities. The information at hand suggests that these waves are not solitons.

Mathematical Model for Axial Crushing of Hybrid Square Tubes

2011 ◽  
Vol 471-472 ◽  
pp. 664-669 ◽  
Author(s):  
H. Akbarshahi ◽  
Mojtaba Sadighi ◽  
Morteza Shakeri ◽  
M. Mirzaei
Keyword(s):  
Mechanical Properties ◽  
Mathematical Model ◽  
Wave Length ◽  
Axial Loading ◽  
Metal Composite ◽  
Metal Tube ◽  
Collapse Mode ◽  
Predicted Values ◽  
Geometrical Dimensions ◽  
Good Agreement

In this paper, to investigate energy absorption capability of hybrid (metal-composite) square tubes under axial loading, a new theory is proposed based on collapse mode of metal square tubes and considering off-axis strength of each layer of composite. An expression is derived for mean crushing load and folding wave length in terms of mechanical properties and geometrical dimensions of metal tube and composite prepregs wrapped around it. To validate the theoretical model, predicted values for mean crushing load are compared with experimental and numerical results that show reasonably good agreement.

scholarly journals Prediction of properties of biodiesel-diesel blends using spectrofluorimetry and multivariate calibration

2012 ◽  
Vol 10 (4) ◽  
pp. 1328-1337 ◽  
Author(s):  
Marilena Meira ◽  
Cristina Quintella ◽  
Iuri Pepe ◽  
Pedro Costa Neto ◽  
Alessandra Santos Tanajura ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Specific Gravity ◽  
Fluorescence Spectroscopy ◽  
Dynamic Viscosity ◽  
Multivariate Calibration ◽  
Pls Regression ◽  
Residual Distribution ◽  
Model Accuracy ◽  
Prediction Of Properties ◽  
Predicted Values

AbstractRegressions based on fluorescence spectroscopy were developed to provide relatively inexpensive and rapid measurements of the concentration, viscosity, and specific gravity of biodiesel-diesel blends. The methods involved obtaining a mathematical model from spectrofluorimetric data and data from a given property (concentration, dynamic viscosity, or specific gravity) using partial least squares (PLS) regression, which was then applied as a model for predicting properties of interest. The predicted concentrations, dynamic viscosities, and specific gravities of the biodiesel-diesel blends were compared with actual values and agreed reasonably well with the obtained results. The models showed high correlation between real and predicted values. The R-square values near 1 indicated excellent model accuracy for predicting concentrations, specific gravities, and dynamic viscosities of biodiesel-diesel blends. The residual distribution did not follow a trend with respect to the predicted variables, indicating an excellent fit to the data.

scholarly journals Computer Modeling in the Application to Geothermal Engineering

2021 ◽  
Vol 2021 ◽  
pp. 1-23
Author(s):  
Karpenko Vasily Nikolaevich ◽  
Yuriy Starodub ◽  
Andrii Havrys
Keyword(s):  
Remote Sensing ◽  
Mathematical Model ◽  
Mathematical Models ◽  
Computer Modeling ◽  
Thermal Energy ◽  
Geothermal Energy ◽  
Heat Fluxes ◽  
The Earth ◽  
Earth’S Interior ◽  
The Mathematical Model

In the article, investigation is given of the developed mathematical models of nonequilibrium in time and distributed in space thermodynamic state of Earth’s matter from its center to its surface depending on the cases of the presence and absence of an internal source of thermal energy concentrated in the center of mass taking into account known geophysical data about the nucleus, mantle, lithosphere and atmosphere, and endogenous and exogenous heat fluxes. The objects of research are as follows: mathematical models of geothermal energy of the Earth, its internal source, and heat balance of endogenous and exogenous heat fluxes on the Earth’s surface. Research methods used are as follows: thermometry in deep wells, ground and remote sensing of heat fluxes of the Earth and the planets of the Solar System, mathematical modeling of heat exchange and thermoelastic processes from compression of Earth’s matter by gravitational field energy information and classical physical and mathematical methods, and computer modeling. The aim of research: in computer modeling to provide new mathematical models that determine the geophysical parameters of geothermal energy, which are aimed on solving problems of energy, environmental and economic security of society, using modern technical means of calculating ground and remote sensing data development of geothermal resources, and regulation of the heat balance of the ecosystem, namely: (i) study of the geological structure of the lithosphere to a depth of 10 km by remote sensing to determine the physical parameters of its layers more accurately than ground methods; (ii) development of projects of geothermal power plants on the basis of single isolated wells of a given depth with a capacity of up to 2 ÷ 3 mW of electricity on continents of the globe; (iii) real-time monitoring and forecasting of the temperature field of the atmosphere according to its physical and chemical composition. The novelty of the obtained research results: (i) developed the mathematical model of the physical process of origin and distribution in the bowels of the density of geothermal energy of the Earth from the surface to its center, which is the density of internal energy of an elementary geological object, and which increases when approaching the center of the planet; (ii) developed the mathematical model of the thermal energy source of infrared (IR) waves of the elementary geophysical object of the Earth’s interior depending on the depth of its occurrence, which allows to determine the stable generation of geothermal energy by rocks in a deep well for extraction and conversion into electricity and to study the geological structure and physical properties of the Earth’s interior; (iii) the mathematical model of heat exchange between the layers of the Earth’s subsoil with the thermal energy of infrared waves according to the laws of Fourier thermal conductivity and Stefan–Boltzmann heat transfer, which together with the geothermal energy source model allows to determine a thermal capacity of rocks in a deep well; (iv) developed the mathematical model of stable action of a source of thermal energy in the center of mass of the Earth, in the absence of which it is hard to explain the power of its endogenous infrared heat flux, parameters of geothermal energy distribution in the Earth, and the current thermodynamic state of the atmosphere, and the change in temperature of which depends on the thermophysical parameters of the physical-chemical composition of the atmosphere more than on changes in the thermal activity of the Sun; (v) determination of new numerical values: thermophysical parameters of the Earth’s interior; kinetic, potential and own gravitational energy of the Earth and own gravitational energy of the planets of the Solar System.

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