A director theory for visco-elastic folding instabilities in multilayered rock

A model for finely layered visco-elastic rock proposed by us in previous papers is revisited and generalized to include couple stresses. We begin with an outline of the governing equations for the standard continuum case and apply a computational simulation scheme suitable for problems involving very large deformations. We then consider buckling instabilities in a finite, rectangular domain. Embedded within this domain, parallel to the longer dimension we consider a stiff, layered beam under compression. We analyse folding up to 40% shortening. The standard continuum solution becomes unstable for extreme values of the shear/normal viscosity ratio. The instability is a consequence of the neglect of the bending stiffness/viscosity in the standard continuum model. We suggest considering these effects within the framework of a couple stress theory. Couple stress theories involve second order spatial derivatives of the velocities/displacements in the virtual work principle. To avoid C-1 continuity in the finite element formulation we introduce the spin of the cross sections of the individual layers as an independent variable and enforce equality to the spin of the unit normal vector to the layers (-the director of the layer system-) by means of a penalty method. We illustrate the convergence of the penalty method by means of numerical solutions of simple shears of an infinite layer for increasing values of the penalty parameter. For the shear problem we present solutions assuming that the internal layering is oriented orthogonal to the surfaces of the shear layer initially. For high values of the ratio of the normal-to the shear viscosity the deformation concentrates in thin bands around to the layer surfaces. The effect of couple stresses on the evolution of folds in layered structures is also investigated. (C) 2002 Elsevier Science Ltd. All rights reserved.

Texture alignment in simple shear

We illustrate the flow behaviour of fluids with isotropic and anisotropic microstructure (internal length, layering with bending stiffness) by means of numerical simulations of silo discharge and flow alignment in simple shear. The Cosserat theory is used to provide an internal length in the constitutive model through bending stiffness to describe isotropic microstructure and this theory is coupled to a director theory to add specific orientation of grains to describe anisotropic microstructure. The numerical solution is based on an implicit form of the Material Point Method developed by Moresi et al. [1].

Anisotropy model for mantle convection

The paper presents a new theory for modeling flow in anisotropic, viscous rock. This theory has originally been developed for the simulation of large deformation processes including folding and kinking in multi-layered visco-elastic rock. The orientation of slip planes in the context of crystallographic slip is determined by the normal vector, the so-called director of these surfaces. The model is applied to simulate anisotropic natural mantle convection. We compare the evolution of the director and approximately steady states of isotropic and anisotropic convection. The isotropic case has a simple steady state solution, whereas the orthotropic convection model produces a continuously evolving patterning in tile core of the convection cell which makes only a near-steady condition possible, in which the thermal boundary layer appears to be well aligned with the flow and hence as observed in seismic tomomgraphy strong anistropic.

A single director switching mode for monodomain liquid crystal elastomer

We report rotation of a single director in a nematic monodomain, acrylate based side-chain elastomer which was subjected to mechanical fields applied at angles in the range to the director, , present at the time of network formation. Time and spatially resolving wide angle X-ray scattering, together with polarised light microscopy measurements revealed a pronounced, almost discontinuous switching mode at a critical extension as the strain was applied at angles approaching to , whereas a more continuous rotation was seen when the strain was applied at more acute angles. This director reorientation was more or less uniform across the complete sample and was accompanied by a modest decrease in orientation parameter . At strains sufficient to induce switching there was some continuous distribution of director orientations with fluctuations of 10 although there was no evidence for any localised director inhomogenities such as domain formation. The observed deformation behaviour of these acrylate-based nematic monodomains was in accord with the predictions of a theory developed by Bladon et al., in that the complete set of data could be accounted for through a single parameter describing the chain anisotropy. The experimentally deduced chain anisotropy parameter was in broad agreement with that obtained from small-angle neutron scattering procedures, but was somewhat greater than that obtained by spontaneous shape changes at the nematic-isotropic transition.

O director de turma como mediador entre o concelho de turma, os alunos, e os encarregados de educação: Contributos para a avaliação da direcção de turma

O presente estudo tem como objectivo investigar o reconhecimento e a relevância do papel do Director de Turma enquanto gestor intermédio para os alunos, os encarregados de educação e para os próprios, tendo em conta a interface inter-relacionai em que a função se desenvolve. Este trabalho teve como pressupostos de base a convicção de que a Educação é um fenómeno complexo que, para além de outras, mobiliza dimensões sociológicas, psicológicas e epistemológicas, além de necessitar, constantemente, de reflexão sobre as suas práticas. Assim, conscientes de que o papel do Director de Turma é de grande importância nas organizações escolares, foi nosso objectivo estudá-lo sob o ponto de vista teórico a partir de uma reflexão na prática e efectuar um estudo empírico do modo como a função é percepcionada como elo de ligação entre os Alunos, os Encarregados de Educação e a Escola. Aborda-se a figura do Director de Turma, enquanto gestor pedagógico intermédio da organização escolar, tendo em conta as atribuições que lhe são consagradas na lei e a forma como os demais parceiros vêm a sua função, em especial numa Escola do 2º e 3° ciclos do Ensino Básico, de acordo com as perspectivas/representações dos próprios actores educativos. O estudo visou em concreto, proporcionar uma análise sustentada do reconhecimento e valorização da figura do Director de Turma enquanto mediador entre o aluno, os encarregados de educação e a Escola. Pretendeu-se, nomeadamente, questionar teórica e empiricamente, a interacção e a articulação entre a formação pessoal, a actuação e as representações dos Directores de Turma. Assim, investigou-se de que modo o Director de Turma, considerado como um agente de mediação, é ou não reconhecido e valorizado enquanto figura responsável pela ligação do aluno e do seu encarregado de educação à Escola. Como opção metodológica optou-se por um estudo de caso, recorrendo à complementaridade entre os procedimentos quantitativos e qualitativos, de acordo com os objectivos visados. Assim, as técnicas de recolha de dados utilizados neste estudo foram o inquérito, por questionário, e a entrevista. Estes instrumentos foram sendo sucessivamente aperfeiçoados. Participaram, a nível do inquérito por questionário, duas turmas, uma do 2° ciclo e outra do 3° ciclo (num total de 45 alunos e respectivos encarregados de educação) e a nível da entrevista, os dois Directores de Turma das turmas envolvidas. Procurou-se, deste modo, contribuir para elucidar em que medida a figura do Director de Turma é reconhecida e valorizada como elo de ligação entre os Alunos, os Encarregados de Educação e a Escola enquanto gestor intermédio. Nas Conclusões após o confronto entre as questões de partida, o quadro teórico e os resultados do estudo empírico, discutem-se as dificuldades e limitações que um estudo desta natureza envolve. Avança-se, por fim, com algumas sugestões que a investigação realizada permite, no sentido de utilizar o conhecimento produzido para melhorar o relacionamento entre o Aluno, os Encarregados de Educação e a Escola e, consequentemente, o processo ensino-aprendizagem. ABSTRACT; The purpose of this study is to investigate the recognition and relevance of the role of the classroom director as an intermediate supervisor to the students, the parents and the classroom director himself, having in mind the inner- relation interface the function takes place. This work was conceived on the basic notion that Education is a complex-phenomenon, setting in motion, among other things, sociological, psychological and epistemological dimensions, as well as requiring, frequently, reflection about its practices. Therefore, conscious of the fact that the role of the class director is of enormous importance within a school environment, our aim was to study it from the theoretical point of view by a reflection in practice and performing an empirical analysis on the way it is understood as a link among the students, parents and the school. The role of classroom director is thus analysed as a pedagogical director in a school setting. Taking into consideration the rights conferred to him/her by law and the way all the other partners assign to the class director, particularly in a 2nd and 3rd cycle of the Elementary School system, in accordance with the perspectives/representations of the education actors. More specifically, this study is an in-depth analysis of the recognition and the valuation of the class director figure as a mediator among the pupils, the parents and the school. ln other words, the interaction between theory and practice in the daily performance of the classroom director were questioned and studied for further analysis. Hence, questioned the way in which the classroom director, seen as a mediation agent, could be considered as a coordinator, recognized and valorized as the responsible figure by the linking among the pupil and his/her parents to the school. The case was realized in the 2nd and 3rd cycle of an elementary school in the Alentejo. As a methodological option, quantitative and qualitative processes were both employed, thus keeping in line with the main objective of this work. Therefore, the data collected and herein utilized were the result of queries, i.e., questionnaires and personal interviews. The former were addressed at the pupils of two classes, one of the 2nd cycle and another of the 3rd cycle of the school and their parents (45 pupils and the same number of parents in total), and the two classroom directors of the classes implicated in the study. ln the Conclusion, a balance of the study is presented, comparing the initial research questions, the theoretical framework, and the results of the empirical analysis developed. A few suggestions are presented from the experience gained in this investigation, i.e., using the knowledge acquired in order to improve and enrich the relationship among the pupils, the parents, the school, and the teaching learning process.

[the Teaching Of Social Sciences In Health: Between Practice And Theory].

The models of teaching social sciences and clinical practice are insufficient for the needs of practical-reflective teaching of social sciences applied to health. The scope of this article is to reflect on the challenges and perspectives of social science education for health professionals. In the 1950s the important movement bringing together social sciences and the field of health began, however weak credentials still prevail. This is due to the low professional status of social scientists in health and the ill-defined position of the social sciences professionals in the health field. It is also due to the scant importance attributed by students to the social sciences, the small number of professionals and the colonization of the social sciences by the biomedical culture in the health field. Thus, the professionals of social sciences applied to health are also faced with the need to build an identity, even after six decades of their presence in the field of health. This is because their ambivalent status has established them as a partial, incomplete and virtual presence, requiring a complex survival strategy in the nebulous area between social sciences and health.

Atomic Charge Transfer-counter Polarization Effects Determine Infrared Ch Intensities Of Hydrocarbons: A Quantum Theory Of Atoms In Molecules Model.

Atomic charge transfer-counter polarization effects determine most of the infrared fundamental CH intensities of simple hydrocarbons, methane, ethylene, ethane, propyne, cyclopropane and allene. The quantum theory of atoms in molecules/charge-charge flux-dipole flux model predicted the values of 30 CH intensities ranging from 0 to 123 km mol(-1) with a root mean square (rms) error of only 4.2 km mol(-1) without including a specific equilibrium atomic charge term. Sums of the contributions from terms involving charge flux and/or dipole flux averaged 20.3 km mol(-1), about ten times larger than the average charge contribution of 2.0 km mol(-1). The only notable exceptions are the CH stretching and bending intensities of acetylene and two of the propyne vibrations for hydrogens bound to sp hybridized carbon atoms. Calculations were carried out at four quantum levels, MP2/6-311++G(3d,3p), MP2/cc-pVTZ, QCISD/6-311++G(3d,3p) and QCISD/cc-pVTZ. The results calculated at the QCISD level are the most accurate among the four with root mean square errors of 4.7 and 5.0 km mol(-1) for the 6-311++G(3d,3p) and cc-pVTZ basis sets. These values are close to the estimated aggregate experimental error of the hydrocarbon intensities, 4.0 km mol(-1). The atomic charge transfer-counter polarization effect is much larger than the charge effect for the results of all four quantum levels. Charge transfer-counter polarization effects are expected to also be important in vibrations of more polar molecules for which equilibrium charge contributions can be large.

Beliefs Related To Adherence To Oral Antidiabetic Treatment According To The Theory Of Planned Behavior.

to identify salient behavioral, normative, control and self-efficacy beliefs related to the behavior of adherence to oral antidiabetic agents, using the Theory of Planned Behavior. cross-sectional, exploratory study with 17 diabetic patients in chronic use of oral antidiabetic medication and in outpatient follow-up. Individual interviews were recorded, transcribed and content-analyzed using pre-established categories. behavioral beliefs concerning advantages and disadvantages of adhering to medication emerged, such as the possibility of avoiding complications from diabetes, preventing or delaying the use of insulin, and a perception of side effects. The children of patients and physicians are seen as important social references who influence medication adherence. The factors that facilitate adherence include access to free-of-cost medication and taking medications associated with temporal markers. On the other hand, a complex therapeutic regimen was considered a factor that hinders adherence. Understanding how to use medication and forgetfulness impact the perception of patients regarding their ability to adhere to oral antidiabetic agents. medication adherence is a complex behavior permeated by behavioral, normative, control and self-efficacy beliefs that should be taken into account when assessing determinants of behavior.

Pedagogia do esporte : pressupostos para uma teoria da avaliação da aprendizagem = Sport pedagogy: presuppositions for a learning assessment theory

Universidade Estadual de Campinas . Faculdade de Educação Física

Pulsar binary systems in a nonsymmetric theory of gravitation II. Dipole radiation

This paper deals with the emission of gravitational radiation in the context of a previously studied metric nonsymmetric theory of gravitation. The part coming from the symmetric part of the metric coincides with the mass quadrupole moment result of general relativity. The one associated to the antisymmetric part of the metric involves the dipole moment of the fermionic charge of the system. The results are applied to binary star systems and the decrease of the period of the elliptical motion is calculated.

Nonexistence of regular stationary solution in a metric nonsymmetric theory of gravitation

It is proven that the field equations of a previously studied metric nonsymmetric theory of gravitation do not admit any non-singular stationary solution which represents a field of non-vanishing total mass and non-vanishing total fermionic charge.

Analyzing the n→π* Electronic Transition of Formaldehyde in Water. A Sequential Monte Carlo/Time-Dependent Density Functional Theory

The n→π* absorption transition of formaldehyde in water is analyzed using combined and sequential classical Monte Carlo (MC) simulations and quantum mechanics (QM) calculations. MC simulations generate the liquid solute-solvent structures for subsequent QM calculations. Using time-dependent density functional theory in a localized set of gaussian basis functions (TD-DFT/6-311++G(d,p)) calculations are made on statistically relevant configurations to obtain the average solvatochromic shift. All results presented here use the electrostatic embedding of the solvent. The statistically converged average result obtained of 2300 cm-1 is compared to previous theoretical results available. Analysis is made of the effective dipole moment of the hydrogen-bonded shell and how it could be held responsible for the polarization of the solvent molecules in the outer solvation shells.

Density functional theory study of Fe(3)Ga

First-principles scalar relativistic calculations in supercells of 16 atoms are used to represent disordered B2 ordering of Fe(3)Ga in order to observe the effect of Ga-Ga pairs on the electronic structure of this alloy. From a comparison with pure bcc Fe it is observed that the energy position and occupation of e(g) and t(2g) states are largely affected by the Ga-Ga pairs and strengthened intraplane interactions takes place. The results show that a larger hybridization of the conduction band is in the source of the magnetostriction enhancement experimentally observed in Galfenol. (C) 2011 American Institute of Physics. [doi:10.1063/1.3525609]

A new constitutive theory extending Hypoplasticity

The purpose of the present theory is to improve Hypoplasticity, especially in relation to reloading processes. This is done by means of two hypoplastic equations (a classical equation along with a new one containing a so-called mnemonic tensor), a cone in stress space and a criterion defining loading, unloading and reloading. (C) 2010 Elsevier Ltd. All rights reserved.