Analytical description of metal plasticity at shift

2020 ◽  
pp. 66-70
Author(s):  
V. N. Shinkin ◽  
Keyword(s):  
Analytical Description ◽  
Metal Plasticity

Quantitative Analysis Of X-Ray Images From Geological Materials

1990 ◽  
Vol 48 (2) ◽  
pp. 244-245
Author(s):  
J. M. Paque ◽  
R. Browning ◽  
P. L. King ◽  
P. Pianetta
Keyword(s):  
Quantitative Analysis ◽  
Bulk Composition ◽  
Principal Component ◽  
Analytical Description ◽  
Bulk Sample ◽  
Geological Samples ◽  
X Ray ◽  
Software And Hardware ◽  
And Storage ◽  
Insight Into

Geological samples typically contain many minerals (phases) with multiple element compositions. A complete analytical description should give the number of phases present, the volume occupied by each phase in the bulk sample, the average and range of composition of each phase, and the bulk composition of the sample. A practical approach to providing such a complete description is from quantitative analysis of multi-elemental x-ray images.With the advances in recent years in the speed and storage capabilities of laboratory computers, large quantities of data can be efficiently manipulated. Commercial software and hardware presently available allow simultaneous collection of multiple x-ray images from a sample (up to 16 for the Kevex Delta system). Thus, high resolution x-ray images of the majority of the detectable elements in a sample can be collected. The use of statistical techniques, including principal component analysis (PCA), can provide insight into mineral phase composition and the distribution of minerals within a sample.

GEOMETRIC THEORY OF MULTIDIMENSIONAL INTERPOLATION

2020 ◽  
Vol 2020 (1) ◽  
pp. 9-16
Author(s):  
Evgeniy Konopatskiy
Keyword(s):  
Response Function ◽  
Algebraic Curves ◽  
Geometric Theory ◽  
Analytical Description ◽  
Geometric Interpretation ◽  
Affine Geometry ◽  
Mathematical Apparatus ◽  
Multidimensional Interpolation ◽  
Pass Through

The paper presents a geometric theory of multidimensional interpolation based on invariants of affine geometry. The analytical description of geometric interpolants is performed within the framework of the mathematical apparatus BN-calculation using algebraic curves that pass through preset points. A geometric interpretation of the interaction of parameters, factors, and the response function is presented, which makes it possible to generalize the geometric theory of multidimensional interpolation in the direction of increasing the dimension of space. The conceptual principles of forming the tree of the geometric interpolant model as a geometric basis for modeling multi-factor processes and phenomena are described.

DETERMINATION OF THE DISTRIBUTION FUNCTION OF THE TIME BETWEEN FAILURES OF A WEAPON MODEL WITHOUT TAKING INTO ACCOUNT THE ENEMY’S FIRE IMPACT

2019 ◽  
pp. 39-45
Author(s):  
M. Sliusarenko ◽  
O. Semenenko ◽  
T. Akinina ◽  
O. Zaritsky ◽  
V. Ivanov
Keyword(s):  
Distribution Function ◽  
Analytical Description ◽  
Time To Failure ◽  
Missile Defense ◽  
Incorrect Choice ◽  
Military Equipment ◽  
Time Between Failures ◽  
The Military ◽  
Fire Impact

In the article, based on the analysis of the requirements for the readiness of weapons and military equipment during combat use and the reliability of their operation in the course of combat operations, it was discovered that one of the reasons that causes a discrepancy between the declared failures and real ones may be the incorrect choice and justification of the time distribution function up to the refusal of military means. As a rule, during the development of these tools, the function of distribution of time to failure is chosen by analogy with similar patterns of weapons and military equipment. In the theory of reliability, special attention is given to choosing the function of time-breaking non-response (failures or failures). Therefore, the article deals with the questions of evaluating the effectiveness of functioning of complex systems and methods of modeling the processes of their functioning, taking into account the laws of the distribution of random variables. The discrepancy between the declared irregularity of the military apparatus and the fact that is actually observed in the troops can be explained by the incorrectly accepted hypothesis about the distribution of time to failure. Therefore, the article analyzes the order of the justification of such a function without taking into account the enemy's fire impact and the proposed variant of determining the function of distribution of the time of work until the refusal of the model of military equipment. The article also cites the reasons for the discrepancy between the claimed missile defense equipment and what is actually observed in the troops. The proposed mathematical model of faultlessness, which at stages of designing and design will allow to set requirements to the model of technology with the help of analytical description. The sequence of calculations of non-failure indexes based on the use of Weibull distribution is substantiated.

Analysis of the temperature curves in non-isothermal adsorption on compacted zeolites

1984 ◽  
Vol 49 (4) ◽  
pp. 911-919 ◽  
Author(s):  
Milan Kočiřík ◽  
Arkadii G. Bezus ◽  
Arlette Zikánová ◽  
Irina T. Erashko ◽  
Michail M. Dubinin ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Heat Transport ◽  
Kinetic Data ◽  
Kinetic Equations ◽  
Analytical Description ◽  
Isothermal Adsorption

An analytical description is presented of the temperature curves describing adsorption on thin zeolite plates. The solution, based on the model of simultaneous mass and heat transport was obtained by linearization of the kinetic equations. A method is proposed for verification of the plausibility of the model and for evaluation of the kinetic data by numerical simulation of the temperature curves.

Analytical Description of Low-Tc DC SQUID Response and Methods for Its Linearization

2017 ◽  
Author(s):  
I. I. Soloviev ◽  
N. V. Klenov ◽  
M. V. Tereshonok ◽  
A. A. Golubov ◽  
A. E. Schegolev ◽  
...  
Keyword(s):  
Analytical Description

scholarly journals Discrete and continuum phenotype-structured models for the evolution of cancer cell populations under chemotherapy

2020 ◽  
Vol 15 ◽  
pp. 14 ◽  
Author(s):  
Rebecca E.A. Stace ◽  
Thomas Stiehl ◽  
Mark A.J. Chaplain ◽  
Anna Marciniak-Czochra ◽  
Tommaso Lorenzi
Keyword(s):  
Cancer Cell ◽  
Cell Population ◽  
Evolutionary Dynamics ◽  
Analytical Description ◽  
Chemotherapeutic Agents ◽  
Cell Populations ◽  
Theoretical Ground ◽  
Individual Based Model ◽  
Nonlocal Parabolic Equation ◽  
Epigenetic Drug

We present a stochastic individual-based model for the phenotypic evolution of cancer cell populations under chemotherapy. In particular, we consider the case of combination cancer therapy whereby a chemotherapeutic agent is administered as the primary treatment and an epigenetic drug is used as an adjuvant treatment. The cell population is structured by the expression level of a gene that controls cell proliferation and chemoresistance. In order to obtain an analytical description of evolutionary dynamics, we formally derive a deterministic continuum counterpart of this discrete model, which is given by a nonlocal parabolic equation for the cell population density function. Integrating computational simulations of the individual-based model with analysis of the corresponding continuum model, we perform a complete exploration of the model parameter space. We show that harsher environmental conditions and higher probabilities of spontaneous epimutation can lead to more effective chemotherapy, and we demonstrate the existence of an inverse relationship between the efficacy of the epigenetic drug and the probability of spontaneous epimutation. Taken together, the outcomes of the model provide theoretical ground for the development of anticancer protocols that use lower concentrations of chemotherapeutic agents in combination with epigenetic drugs capable of promoting the re-expression of epigenetically regulated genes.

scholarly journals A Modified Phase-Field Damage Model for Metal Plasticity at Finite Strains: Numerical Development and Experimental Validation

Metals ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 47
Author(s):  
Jelena Živković ◽  
Vladimir Dunić ◽  
Vladimir Milovanović ◽  
Ana Pavlović ◽  
Miroslav Živković
Keyword(s):  
Phase Field ◽  
Damage Evolution ◽  
Deformation Gradient ◽  
Damage Model ◽  
Steel Structures ◽  
Plasticity Model ◽  
Metal Plasticity ◽  
Damage And Fracture ◽  
Von Mises ◽  
Von Mises Plasticity

Steel structures are designed to operate in an elastic domain, but sometimes plastic strains induce damage and fracture. Besides experimental investigation, a phase-field damage model (PFDM) emerged as a cutting-edge simulation technique for predicting damage evolution. In this paper, a von Mises metal plasticity model is modified and a coupling with PFDM is improved to simulate ductile behavior of metallic materials with or without constant stress plateau after yielding occurs. The proposed improvements are: (1) new coupling variable activated after the critical equivalent plastic strain is reached; (2) two-stage yield function consisting of perfect plasticity and extended Simo-type hardening functions. The uniaxial tension tests are conducted for verification purposes and identifying the material parameters. The staggered iterative scheme, multiplicative decomposition of the deformation gradient, and logarithmic natural strain measure are employed for the implementation into finite element method (FEM) software. The coupling is verified by the ‘one element’ example. The excellent qualitative and quantitative overlapping of the force-displacement response of experimental and simulation results is recorded. The practical significances of the proposed PFDM are a better insight into the simulation of damage evolution in steel structures, and an easy extension of existing the von Mises plasticity model coupled to damage phase-field.

A novel model for the interpretation of small-angle scattering experiments of self-affine structures

2009 ◽  
Vol 43 (1) ◽  
pp. 12-16 ◽  
Author(s):  
Gerald J. Schneider ◽  
D. Göritz
Keyword(s):  
Small Angle ◽  
Analytical Description ◽  
Small Angle Scattering ◽  
Filled Rubber ◽  
Angle Scattering ◽  
Affine Structures ◽  
Novel Theory ◽  
First Time ◽  
Novel Model ◽  
Solid Spheres

A novel theory is presented which allows, for the first time, the analytical description of small-angle scattering experiments on anisotropic shaped clusters of nanoparticles. Experimentally, silica-filled rubber which is deformed is used as an example. The silica can be modelled by solid spheres which form clusters. The experiments demonstrate that the clusters become anisotropic as a result of the deformation whereas the spheres are not affected. A comparison of the newly derived model function and the experiments provides, for the first time, microscopic evidence of the inhomogeneous deformation of clusters in the rubbery matrix.

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