Self-Consistent Approaches and Strain Heterogeneities in Two-Phase Elastoplastic Materials

1994 ◽  
Vol 47 (1S) ◽  
pp. S66-S76 ◽  
Author(s):  
Michel Bornert ◽  
Eveline Herve´ ◽  
Claude Stolz ◽  
Andre´ Zaoui
Keyword(s):  
Deformation Theory ◽  
Shear Bands ◽  
Local Concentration ◽  
Two Phase ◽  
Self Consistent ◽  
Measured Strain ◽  
Elastoplastic Materials ◽  
Hardening Parameter ◽  
Analytical Result ◽  
Definition Of

The Generalized Self Consistent Scheme [GSCS] extended to the nonlinear case with help of a deformation theory of elastoplasticity is used to predict the strain heterogeneities that spread out in two phase elastoplastic materials submitted to a monotonic uniaxial load. Materials with different microstructural morphologies are considered. The single composite inclusion of the GSCS is an accurate representation of “matrix/inclusion” microstructures but it does not give a sufficient representation of the considered morphologies. That’s why this model is extended to more general cases by using two or even more different spherical composite inclusions: local concentration fluctuations and local morphological inversions can then be modeled. The nonlinear extension is also modified: the composite inclusions are discretized into several concentric layers in order to take into better account the strain gradient along the radius and a new definition of the work-hardening parameter of each of these layers is proposed. The elastoplastic strain field in the single composite inclusion is also computed numerically by means of finite element methods and compared to the analytical result. Unfortunately, these modifications do not basically modify the strain heterogeneity predictions of the GSCS, which widely underestimate the measured strain heterogeneities in most of the cases. In fact, the inaccuracy of the GSCS in these cases is basically due to the appearance of long range shear bands that cannot be described by a local self-consistent approach.

scholarly journals Validation of Sexological Worldview

SAGE Open ◽  
2012 ◽  
Vol 2 (1) ◽  
pp. 215824401243907 ◽  
Author(s):  
Justin A. Sitron ◽  
Donald A. Dyson
Keyword(s):  
Attitude Change ◽  
Service Provision ◽  
Perspective Transformation ◽  
The United States ◽  
Qualitative Approach ◽  
Second Phase ◽  
Two Phase ◽  
Convenience Sample ◽  
Developmental Characteristics ◽  
Definition Of

The authors originally posited that a new construct must be developed to measure the success of affective training for sexologists, particularly the Sexuality Attitudes Reassessment (SAR) modality. Couching their critique in studies that have been conducted to measure the SAR’s effectiveness as a method used to evoke perspective transformation and more sensitive and humanistic service provision, the authors argued that the development of a professional’s sexological worldview would be a more accurate construct than attitude change to measure when considering the outcomes of SAR training. This study in the United States used a two-phase qualitative approach to validate the proposed sexological worldview construct. In the first phase, they surveyed a panel of 16 sexologists regarding their original proposed definition of sexological worldview and refined it. In the second phase, they completed 30 one-on-one interviews with a convenience sample of sexologists and sexology students. Using an inductive content analysis of the interview transcripts, seven themes emerged in support of the proposed definition of sexological worldview, including its components and its developmental characteristics. The article concludes with a discussion of the implications for the use of the construct for the training of sexologists.

Dissociation and Subsidence of Hydrated Sediment: Coupled Models

2009 ◽  
Vol 27 (2) ◽  
pp. 105-131 ◽  
Author(s):  
Mohamed Iqbal Pallipurath
Keyword(s):  
Thermal Dissociation ◽  
Hydrate Formation ◽  
Coupled Models ◽  
Two Phase ◽  
Strength Deterioration ◽  
Intrinsic Kinetics ◽  
Radial Heat Flow ◽  
Radial Heat ◽  
Definition Of ◽  
Pressure Changes

Thermal dissociation of hydrated sediment by a pumped hot fluid is modeled. A radial heat flow from the hot pipe is assumed. The coordinate system is cylindrical. Three components (hydrate, methane and water) and three phases (hydrate, gas, and aqueous-phase) are considered in the simulator. The intrinsic kinetics of hydrate formation or dissociation is considered using the Kim-Bishnoi model. Mass transport, including two-phase flow, molecular diffusions and heat transfer involved in formation or dissociation of hydrates are included in the governing equations, which are discretized with finite volume difference method and are solved in an explicit manner. The strength deterioration of the hydrate bed as a result of dissociation is investigated with a geo-mechanical model. The way in which dissociation affects the bed strength is determined by plugging in the porosity and saturation change as a result of dissociation into the sediment collapse equations. A mechanism to measure the pore pressure changes occurring due to dissociation is developed. The rate of collapse as dissociation proceeds is determined and the model thus enables the definition of a safety envelope for gas hydrate drilling.

scholarly journals Self-consistent two-phase AGN torus models

2015 ◽  
Vol 583 ◽  
pp. A120 ◽  
Author(s):  
Ralf Siebenmorgen ◽  
Frank Heymann ◽  
Andreas Efstathiou
Keyword(s):  
Two Phase ◽  
Self Consistent

scholarly journals Trust motivation: The self-regulatory processes underlying trust decisions

2019 ◽  
Vol 9 (2-3) ◽  
pp. 99-123 ◽  
Author(s):  
Lisa van der Werff ◽  
Alison Legood ◽  
Finian Buckley ◽  
Antoinette Weibel ◽  
David de Cremer
Keyword(s):  
Goal Setting ◽  
Feedback Loop ◽  
Future Research ◽  
Two Phase ◽  
Cognitive Trust ◽  
Regulatory Processes ◽  
Dynamic View ◽  
Definition Of ◽  
And Behavior ◽  
And Control

Theorizing about trust has focused predominantly on cognitive trust cues such as trustworthiness, portraying the trustor as a relatively passive observer reacting to the attributes of the other party. Using self-determination and control theories of motivation, we propose a model of trust motivation that explores the intraindividual processes involved in the volitional aspects of trust decision-making implied by the definition of trust as a willingness to be vulnerable. We distinguish between intrinsic and extrinsic drivers of trust and propose a two-phase model of trust goal setting and trust regulation. Our model offers a dynamic view of the trusting process and a framework for understanding how trust cognition, affect and behavior interact over time. Furthermore, we discuss how trust goals may be altered or abandoned via a feedback loop during the trust regulation process. We conclude with a discussion of potential implications for existing theory and future research.

scholarly journals Numerical simulation of modification of non-metallic inclusions by calcium treatment in the argon-stirred ladle

2019 ◽  
Vol 116 (5) ◽  
pp. 515
Author(s):  
Edgar Ivan Castro-Cedeno ◽  
Alain Jardy ◽  
Benjamin Boissiere ◽  
Jean Lehmann ◽  
Pascal Gardin ◽  
...  
Keyword(s):  
Flow Model ◽  
Fluid Dynamic ◽  
Steel Ladle ◽  
Local Concentration ◽  
Two Phase ◽  
Euler Flow ◽  
Metallic Inclusions ◽  
Dissolved Species ◽  
Secondary Steelmaking ◽  
Technological Challenge

Nowadays, depending on the steel grade, Ca treatment with the aim of modifying the morphology and melting temperature of non-metallic inclusions is performed in the secondary steelmaking process. The addition of calcium to steel melts rises a technological challenge because at steelmaking temperatures Ca has the tendency to vaporize from the ladle. Efforts are actively pursued in developing solutions that increase Ca yield and improve repeatability of results from treatment to treatment. This work presents a two-phase Euler-Euler flow model of a steel ladle with gas stirring through bottom porous plugs. The model considers that before gas exits through the ladle top, some Ca is transferred from the gas to the liquid steel. The yield is thus defined as the ratio between the Ca transferred to the steel and the total calcium injected into the ladle. The fluid-dynamic calculations are coupled with ArcelorMittal thermodynamic software CEQCSI to get the evolution of the local concentration of dissolved species and non-metallic inclusions assuming local thermodynamic equilibrium. Industrial trials have been performed at one of ArcelorMittal’s facilities with the aim of obtaining data to validate the model. Samples of steel were taken before, during, and after the Ca injection treatment. The total Ca content and the inclusion populations in the steel samples can be compared against the results given by the model, as well as the measured and calculated Ca yield.

scholarly journals DEFORMATION CONDITIONS FOR PSEUDOREPRESENTATIONS

2019 ◽  
Vol 7 ◽  
Author(s):  
PRESTON WAKE ◽  
CARL WANG-ERICKSON
Keyword(s):  
Stability Condition ◽  
Deformation Theory ◽  
Axiomatic Definition ◽  
Galois Deformation ◽  
Definition Of

Given a property of representations satisfying a basic stability condition, Ramakrishna developed a variant of Mazur’s Galois deformation theory for representations with that property. We introduce an axiomatic definition of pseudorepresentations with such a property. Among other things, we show that pseudorepresentations with a property enjoy a good deformation theory, generalizing Ramakrishna’s theory to pseudorepresentations.

scholarly journals Real gas state equations comparative analysis for low-temperature calculations

2019 ◽  
Vol 140 ◽  
pp. 05007 ◽  
Author(s):  
Mikhail Sokolov ◽  
Nikolay Sadovsky ◽  
Anatoly Zuev ◽  
Lyubov Gileva ◽  
Minh Hai Nguyen
Keyword(s):  
Comparative Analysis ◽  
Low Temperature ◽  
Exact Equation ◽  
Gas Temperature ◽  
State Equations ◽  
Two Phase ◽  
Accurate Identification ◽  
Real Gas ◽  
Mass Transfer Processes ◽  
Definition Of

In this paper, various real gas state equations are considered and their comparative analysis is carried out. The following state equations are studied in the work: Benedict-Webb-Rubin modification equation, Ridlich-Kwong Real Gas equation, Peng-Robinson Real Gas equation, and the modified Ridlich-Kwong real gas state equations proposed by Barsuk S.D. We have made a direct comparison of these calculation methods with most accurate identification. In addition, the paper analyzes the equations features, with applicability limits definition of each state equations. For the chosen one, as the most universal and exact equation, the calculations were made for the liquid phase and the real gas two-phase state. Based on the data obtained, polynomials were developed for various parameters depending on the gas temperature, which can later be used to build various mathematical models. Our conclusions show main advantages of selected equation for real gases and the reasons for choosing it for modeling low-temperature heat and mass transfer processes.

Tight-Binding Study of the {211} Σ=3 Grain Boundary in Cubic Silicon-Carbide

1994 ◽  
Vol 339 ◽  
Author(s):  
M. Kohyama ◽  
R. Yamamoto
Keyword(s):  
Grain Boundaries ◽  
Electronic Structures ◽  
Tight Binding ◽  
The Self ◽  
Localized States ◽  
General Definition ◽  
Self Consistent ◽  
Tight Binding Method ◽  
Definition Of ◽  
Cubic Silicon Carbide

ABSTRACTIn grain boundaries in compound semiconductors such as SiC, the interface stoichiometry and the wrong bonds between like atoms are of much importance. Firstly, a general definition of the interface stoichiometry in such grain boundaries has been discussed. Secondly, the atomic and electronic structures of the {211} Σ=3 boundary in SiC have been examined by using the self-consistent tight-binding method, based on the atomic models with bonding networks similar to those in the models of the same boundary in Si or Ge. The wrong bonds have significant effects through the large electrostatic repulsion and the generation of localized states as well as those in the {122} Σ=9 boundary in SiC. And the different bond lengths of the wrong bonds very much affect the local bond distortions at the interfaces, which determines the relative stability among the present models.

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