La propagation des ondes sismiques dans les milieux poreux multiphasiques présente des enjeux nombreux, tant sur le plan environnemental (risques naturels, géotechnique, pollutions de nappes...) que pour les réservoirs (aquifères, hydrocarbures, stockages de CO2...). L'utilisation des ondes sismiques pour étudier ces milieux se justifie par le fait qu'en se propageant, les ondes sont déformées par le milieu qu'elles traversent et contiennent ainsi des informations aux capteurs sur les phases fluides et solides et sur le squelette poreux. Ce travail de thèse s'intéresse aux caractéristiques des ondes sismiques dans les milieux multiphasiques (plusieurs phases fluides et solides), depuis la description physique jusqu'à la caractérisation des paramètres constitutifs par inversion, en passant par la modélisation numérique 2D de la propagation. La première partie du travail a consisté à décrire la physique des milieux multiphasiques (phase par phase et leurs intéractions dynamiques) en utilisant des méthodes d'homogénéisation pour se ramener à un milieu équivalent défini par sept paramètres. Ainsi, dans des milieux simple porosité saturés et dans des milieux plus complexes (double porosité, partiellement saturés ou visco-poroélastiques), je peux calculer la propagation des ondes sismiques sans approximation. En effet, j'utilise une méthode numérique dans le domaine fréquence-espace qui permet de prendre en compte tous les termes qui dépendent de la fréquence sans approximation. La discrétisation spatiale utilise une méthode d'éléments finis discontinus (Galerkin discontinu) qui permet de considérer des milieux hétérogènes.Je montre notamment que les attributs sismiques (vitesses et atténuations) des milieux poreux complexes sont fortement dispersifs et les formes d'ondes complètes, calculées sans approximation, sont fortement dépendantes de la description physique du milieu. La caractérisation des paramètres poroélastiques s'effectue par inversion. Une méthode en deux étapes a été proposée : la première consiste en une inversion ``classique`` (tomographie, inversion des formes d'ondes complètes) des données (sismogrammes) pour obtenir des paramètres macro-échelles (attributs sismiques). La seconde étape permet de reconstruire, à partir des paramètres macro-échelles, les paramètres poroélastiques micro-échelles. Cette étape d'inversion utilise une méthode d'optimisation semi-globale (algorithme de voisinage). Une analyse de sensibilité montre qu'en connaissant a-priori certains paramètres, on peut inverser avec précision les paramètres du squelette poroélastique ou retrouver la nature du fluide saturant, à partir des vitesses de propagation. En revanche, pour retrouver la saturation en fluide, il est préférable de connaître les atténuations. Deux applications réalistes (monitoring de réservoir et hydrogéophysique) mettent en oeuvre ce type d'inversion en deux étapes et démontrent qu'à partir de données estimées par des méthodes classiques d'imagerie, on peut remonter à certains paramètres poroélastiques constitutifs. / Seismic wave propagation in multiphasic porous media have various environmental (natural risks, geotechnics, groundwater pollutions...) and ressources (aquifers, oil and gas, CO2 storage...) issues. When seismic waves are crossing a given material, they are distorted and thus contain information on fluid and solid phases. This work focuses on the characteristics of seismic waves propagating in multiphasic media, from the physical complex description to the parameter characterisation by inversion, including 2D numerical modelling of the wave propagation. The first part consists in the description of the physics of multiphasic media (each phase and their interactions), using several upscaling methods, in order to obtain an equivalent mesoscale medium defined by seven parameters. Thus, in simple porosity saturated media and in complex media (double porosity, patchy saturation, visco-poroelasticity), I can compute seismic wave propagation without any approximation. Indeed, I use a frequency-space domain for the numerical method, which allows to consider all the frequency dependent terms. The spatial discretisation employs a discontinuous finite elements method (discontinuous Galerkin), which allows to take into account complex interfaces.The computation of the seismic attributes (velocities and attenuations) of complex porous media shows strong variations in respect with the frequency. Waveforms, computed without approximation, are strongly different if we take into account the full description of the medium or an homogenisation by averages. The last part of this work deals with the poroelastic parameters characterisation by inversion. For this, I develop a two-steps method: the first one consists in a classical inversion (tomography, full waveform inversion) of seismograms data to obtain macro-scale parameters (seismic attributes). The second step allows to recover, from the macroscale parameters, the poroelastic micro-scale properties. This downscaling step uses a semi-global optimisation method (neighbourhood algorithm), which allows the sampling of the full model space (thanks to the low numerical cost of the analytic direct model). With the a-priori knowledge of some parameters, a sensibility analysis shows that I can invert precisely skeleton parameters or the saturating fluid type, from the velocities only. Nevertheless, to recover the fluid saturation, it is preferable to use the attenuations. This two-steps procedure is tested on two realistic applications (reservoir monitoring and subsurface hydrogeophysics) and show that we can recover some constituve poroelastic parameters.

Thesis (Ph. D.)--Ohio State University, 2006. / Title from first page of PDF file. Includes bibliographical references (p. 231-247).

The evolution of the Systems Model approach to personnel selection marks the emergence of the relationship between the organization and the applicant. It has made organizations become increasingly aware of the potential influence of applicant reactions to selection procedures.

Dans ce travail, les propriétés thermiques effectives du milieu fibreux sont déterminées en tenant compte du couplage conduction et rayonnement. Un échantillon numérique fibreux statistiquement homogène composé de deux phases a été généré en empilant des cylindres finis absorbant dans le vide. Ces cylindres sont dispersés selon des fonctions de distribution de la position de leur centre et de leur orientation. L'interpénétration des cylindres est permis. L'extinction, l'absorption et la diffusion sont caractérisées par des fonctions statistiques radiatives qui permettent de savoir si le milieu est Beerien (ou non). Elles sont déterminées précisément à l'aide d'une méthode de Monte Carlo. On montre que la phase gazeuse a un comportement Beerien et que le phase fibreuse a un comportement fortement non Beerien. Le champ de puissance radiative déposée dans le milieu fibreux est calculé en résolvant un modèle qui couple une Équation du Transfert Radiatif Généralisée (ETRG) et une Équation du Transfert radiatif Classique (ETR). Le modèle de conduction thermique est basé sur une méthode de marche aléatoire ne nécessitant aucun maillage. La simulation du mouvement Brownien de marcheurs dans les fibres permet de résoudre l'équation de l'énergie. L'idée de la méthode est de caractériser la température d'un volume élémentaire par une densité de marcheurs, qui peuvent parcourir le milieu. Le problème est gouverné par les conditions aux limites ; Une concentration constante de marcheurs (ou un flux constant) est associée à une température imposée (ou un flux). / In the present work, the effective heat transfer properties of fibrous medium are determined by taking into account a coupling of heat conduction and radiation. A virtual, statistically homogeneous, two-phase fibrous sample has been built by stacking finite absorbing cylinders in vaccum. These cylinders are dispersed according to prescribed distribution functions defining the cylinder positions and orientations. Cylinder overlappings are allowed. Extinction, absorption and scattering are characterised by radiative statistical functions which allow the Beerian behaviour of a medium to be assessed (or not). They are accurately determined with a Monte Carlo method. Whereas the gaseous phase exhibits a Beerian behaviour, the fibre phase is strongly non Beerian. The radiative power field deposited within the fibrous material is calculated by resolving a model which couples a Generalized Radiative Transfer Equation (GRTE) and a classic Radiative Transfer Equation (RTE). The model of conduction transfer is based on a random walk method without meshing. The simulation of Brownian motion of walkers in fibres allows the energy equation to be solved. The idea of the method is to characterize the temperature in an elementary volume by the density of walkers, which roam the medium. The problem is governed by boundary conditions ; A constant concentration of walkers (or a constant flux) is associated with a fixed temperature (or flux).

“The relationship between the criminal and victim is much more complicated than the law would care to acknowledge. The criminal and his victim work on each other unconsciously. We can say that as the criminal shapes the victim, the victim also shapes the criminal. The law differentiates distinctly between the attacker and the victim. But their relationship may be, and often is, quite close, so that their roles are reversed and the victim becomes the determining person, while the [victimiser] in the end becomes his own victim.” (Abrahamsen, 1973:35). This research was directed at establishing whether narcissistic individuals will go to extreme levels of violence, specifically murder, if their self-image is threatened. The aim was to determine the extent of pre-existing narcissistic personality disorder (NPD) in these individuals and how this contributed to the murderous action they committed. Emphasis was placed on the psychological motivation of the perpetrator, as well as the relationship that existed between the perpetrator and the victim prior to the event. As the subject of the research was a relatively unknown phenomenon, a qualitative research approach was used. The research focused on analysing specific cases of murder, more particularly cases where rage-type murders were committed. It endeavoured to identify the underlying personality dynamics to determine whether an association between rage-type murder and NPD exists. Case studies illustrating rage-type murderers who had been admitted to Weskoppies Psychiatric Hospital for a 30-day observation period were identified and analysed. These cases were selected through reviewing the case history of each individual to determine whether the murder fitted the outlined definition of a rage-type murder. The cases that met the outlined requirements were deemed suitable for the purpose of the research, where after the Minnesota Multiphasic Personality Inventory (MMPI-2) results of the selected cases were examined to determine the personality organisation of the individuals. This information was then used to determine the possible association between NPD and rage-type murder. The MMPI-2 was selected as the assessment tool as it is the most widely used personality assessment available. For the purposes of this research a two-point code type was used to indicate the presence of narcissistic personality traits. A two-point code type implies an elevation of two scales, for the purposes of this research specifically the Pd (Psychopathic deviance) scale and the Pa (Paranoia) scale, also referred to as the 4-6/6-4 code type. As interpretation based only on a two-scale elevation was considered to be overly simplistic, all the MMPI-2 clinical scales were interpreted independently, and a clinical interpretation provided in the context of each individual’s background. The 4-6/6-4 code type individual was used to indicate whether the individuals did have narcissistic personality traits, and thus were classified as having NPD. Nine cases were identified of individuals thought to be rage-type murderers, who were admitted for a 30-day period of psychiatric observation to Weskoppies Psychiatric Hospital in Pretoria. Only five cases were acknowledged as rage-type murders. All the cases selected were referred to Weskoppies Psychiatric Hospital by order of the court and involved males over the age of 20 years. The individuals involved were admitted to the Forensic Unit of the hospital and were subjected to standard psychiatric hospital observations, which included psychiatric interviews, psychological interviews, psychological testing, as well as general behavioural observations in the ward. All the information obtained during the standard psychiatric hospital observations is held in the clinical case files in the archives at the hospital. All the standard psychiatric hospital observation evaluations were completed prior to the initiation of the research, and the case records had been closed. Although more research is necessary, this research has established an association between the selected cases of rage-type murder and NPD and there is historic documented evidence suggesting that individuals with NPD will most likely react in a similar manner in similar circumstances, as a result of their underlying personality disorder. This suggests that incarceration in a correctional facility is not the most appropriate place to rehabilitate individuals. It also serves as support to why a person with NPD who commits a rage-type murder should be acquitted because of their personality disorder and subsequently be committed to a psychiatric facility as a patient of the state president. / Dissertation (MA)--University of Pretoria, 2010. / Social Work and Criminology / unrestricted

Purpose of the Study The thesis of this study is that personality characteristics can be shown as factors in the variation of behavior which occurs during labor and childbirth. It is felt that if personality traits can be measured by a standard device they will correlate with various types of behavior expressed during labor. The Minnesota Multiphasic Personality Inventory is one instrument which tests all of the more important phases of personality. This test was chosen as the device to be used in this study to determine the personality traits of the women involved. Therefore, the purpose of this study is to determine if the scores obtained in the Minnesota Multiphasic Personality Inventory can be used to correlate personality traits with the behavior expressed during labor. Assuming that behavior can be predicted, it can be hypothesized that doctors could use the Minnesota Multiphasic Personality Inventory or some other personality test to study their patients personalities early in pregnancies and could counsel them in overcoming emotional and personal problems. This should make the patients labors and deliveries much easier. With the increased interest during the past few years in the psychological factors involved in pregnancy, it is felt that a study of personality traits might point a way to further study in this field. To this end the chief objective of this research has been to determine whether a positive correlation can be found between observed types of behavior during labor and delivery and scores on the Minnesota Multiphasic Personality Inventory. Method of procedure Seven basic behavior types showing reactions expressed during labor and delivery were devised by six nurses with obstetrical experience. Patients were chosen who had no previous childbearing experience and who received a limited amount of medication. The patients were observed during labor and then placed in one of the behavior categories. The day after delivery the patients were given the Minnesota Multiphasic Personality Inventory. This method of procedure is discussed more fully in Chapter Three.