Thesis (Ph.D.) - University of Queensland, 2003. / Includes bibliography.

L'étude des arcs électriques dans les liquides débute au XXème siècle suite à la création des premiers disjoncteurs à bain d'huile et à l'utilisation de différents procédés de soudure/découpe en pleine eau de coques de navire. Ces études ont été délaissées pendant environ 60 ans jusqu'à ce que de nouvelles applications voient le jour comme la fabrication de nanostructures (pour le génie électrique, la médecine, etc), la fracturation électrique ou encore diverses applications environnementales (dépollution, stérilisation, gazéification, ondes de chocs). Ces diverses applications se font avec des temps et des énergies mises en jeu pour la décharge très variables. Malgré ces différences, il y a toujours l'apparition d'une phase gazeuse globalement sphérique due au passage du courant. Cependant, cette phase est très peu étudiée dans la littérature notamment pour des décharges de l'ordre du kilojoule pour des durées de 10ms environ. L'objectif de la thèse est donc d'améliorer la compréhension de la formation et de la dynamique de la bulle de gaz alimentée par cet arc en jouant sur certains paramètres du système. Les travaux effectués s'articulent suivant deux axes : une étude expérimentale pour analyser le comportement de cette bulle par rapport à l'arc en modifiant notamment l'énergie injectée, la distance inter-électrode utilisée ou encore la nature du fluide employé ; et une étude numérique où un modèle diphasique 2D a été mis en œuvre sous Ansys Fluent pour simuler la création et le développement de cette phase gazeuse au sein d'une phase liquide. La complémentarité de ces deux études permet de témoigner de la présence de certains mécanismes comme ceux de la formation de bulles ou de cycles d'expansion et d'effondrement, gouvernés par des phénomènes de chauffage, d'évaporation ou électrothermiques. L'expérience mise en place se compose d'un réacteur hermétique en aluminium où l'arc électrique est amorcé par un fil fusible entre deux électrodes dans un liquide : eau ou huile. Des hublots permettent la visualisation par caméra rapide de l'espace inter électrode, et donc de l'arc et de la bulle de gaz qu'il engendre. Les caractéristiques courant et tension de l'arc électrique sont suivies dans le temps. Un capteur de pression dans le volume d'air situé au-dessus du liquide contrôle l'onde de pression générée par la décharge. Les résultats expérimentaux sont traités sous Matlab et permettent de conforter le modèle numérique mis en place. Le code utilise les équations de Navier-Stokes pour décrire les deux phases du fluide via la méthode Volume-Of-Fluids (VOF). A ces développements a aussi été intégré un modèle pour prendre en compte le transfert d'une phase de fluide vers une autre. Pour nos conditions de températures élevées, ce modèle a dû être adapté via le coefficient d'intensité de transfert de masse, qui est décrit en fonction de la température et de la proportion de phase dans une cellule. Les résultats de simulation issus de ce modèle permettent d'appuyer les observations expérimentales, et de poser les bases d'une étude sur la formation et le comportement de la phase gazeuse produite par le passage d'un arc électrique dans un liquide. / The study of electrical arcs in liquids begins in XXth century with the first oil circuit breaker and the use of welding/cutting processes on ship hulls in full water. These studies have been neglected for about 60 years, until the emergence of new applications such as the manufacture of nanostructures (for electrical engineering, medicine, etc.), electrical arc fracturing or different environmental applications (depollution, sterilization, gasification). In these applications different times and energies scales are involved for the discharge characteristics. Despite these differences, in all configurations a spherical gaseous medium dues to the current carrying path in the liquid exists. However, this gaseous phase is not much studied in the literature, particularly for an energy discharges of the order of kilojoule applied during 10ms. The goal of the thesis was to improve the understanding and to interpret the formation and the dynamic of the gas bubble created by this arc by varying the conditions. The work follows two ways: an experimental study to analyze the behavior of the bubble depending on the arc characteristics as the energy injected, the distance between the electrodes or the nature of the fluid; And a numerical study, where a 2D diphasic model has been implemented under Ansys Fluent to simulate the creation and the expansion of this gaseous phase in a liquid. The complementarity of these two approaches allows complementarities and interpretations. The experiment set up is composed by a closed aluminum reactor, where the electric arc is established in a liquid (water or oil) by a fusible wire between two electrodes. Windows allows to visualize by a speed camera the inter-electrode space, and so the arc and the gas bubble created. The current and voltage characteristics of the electric arc are recorded over time. A pressure sensor located in the volume of air above the liquid controls the pressure variations. The experimental results are treated through Matlab software and allow corroborating the numerical model developments. The code uses the Navier-Stokes equations to describe the two phases of the fluid via the Volume-Of-Fluids (VOF) method. Specifics developments have also been integrated to take into account the phase transfer at the gas/liquid interface adapting the mass transfer intensity coefficient. This coefficient is described as a function of the temperature and of the proportion of phase in a cell. The simulation results from the model support the experimental observations and build the foundations for a study on the behavior of the gaseous phase produced by the passage of an electric arc in a liquid.

The purpose of this study is to replicate and extend earlier work involving cluster analysis of MMPI profiles among persons with chronic low back pain. There are two specific goals. The first goal is to demonstrate the existence in a new sample of four distinct and homogenous profile clusters that have been found in previous research. The second goal is to investigate the relationship of the four profiles to the subjects, self-reported pain history and response to treatment. This study concludes that four distinct MMPI profiles can be identified among chronic low back pain patients. Further, these profiles are the same for males and females, and are the same profiles found in previous research. These profiles are significantly related to subjects' history of behaviors in dealing with pain. However, no relationship to treatment response was found. It was inferred that the MMPI is of value in understanding the nature of patients' pain coping behaviors, but that further research is needed before any statements can be made regarding the utility of the MMPI in understanding their response to treatment.

A descoberta de petróleo na camada do Pré-Sal fez com que a Petrobras envestisse cerca de 240 bilhões de dólares. Uma etapa crítica desta indústria é o transporte de petróleo, que envolve o sistema água-óleo. O objetivo do presente trabalho é estudar uma corrente água-óleo em um tubo reto e em uma curva, com o intuito de gerar perfis de velocidades, pressões e densidades em CFD. Para as simulações desenvolvidas foram considerados: fluxo 3D, escoamento turbulento na fase óleo e escoamento laminar na fase água, isotérmico e incompressível. Foram realizados estudos nos estados estacionário e transiente. Foi desenvolvido o estudo de convergência da malha. As ferramentas do Phoenics utilizadas para representar a interação entre as fases foram o IPSA e o Algebraic Slip. O IPSA resolve as equações de Navier-Stokes para cada fase. No Algebraic Slip, postula-se que existe um meio contínuo em que existem vários componentes da fase dispersos, podendo estes ser gotas, bolhas ou partículas sólidas. A turbulência foi avaliada utilizando os modelos K- padrão e o K-, porém só houve redução considerável dos resíduos para o K- Padrão. As densidades geradas nas simulações em CFD foram comparadas visualmente com os resultados experimentais obtidos em trabalho anterior para fluxo multifásico. As quedas de pressão obtidas em simulação foram comparadas com os dados da literatura, onde foi possível observar a grande redução da perda de carga ao utilizar a técnica de envolver o óleo com um anel de água na tubulação. As simulações realizadas com o modelo Algebraic Slip, e o modelo de turbulência foram consideradas como validadas. / With the discovery of oil in the pre-salt layer, Petrobras was encouraged to invest about 240 billion dollars. A critical point of this industry is the oil transport, which encompasses oil-water system. The objective of the present work is to study the flow of water and oil into a tube and an elbow, in order to generate distributions of velocity, pressure and density by using a CFD tool. To develop simulations the following is assumed: 3D flow, turbulent flow in oil phase and laminar flow in water phase, isotherm and incompressible flow. Steady-state and transient studies have been done. The mesh convergence has been carried out. The IPSA and Algebraic slip were the Phoenics tools that were used to represent the phases interaction. The IPSA solves the Navier-Stokes equations for each phase. In the Algebraic Slip model, one assumes that a continuum mean exists where the other components are dispersed, which can be bubbles or solid particles. The turbulence was evaluated by using K- standard and K- models; however, the considerable reduction of residue to the K- Standard was observed. The densities modeled by CFD were visually compared to the experimental results that were obtained in a previous work for a multiphase flow. The simulations of head loss were compared to literature data, and it can be seen a big difference between the head loss that was obtained by using water and that no using water. The simulations of Algebraic Slip model and the use of turbulence model were considered as validated.

Abstract Both genetic and environmental factors and gene-environment interaction have been found to contribute to the development of schizophrenia. Predisposition may manifest as prodromal vulnerability indicators before the onset of disease. The aim was to search for vulnerability signs of schizophrenia spectrum disorders, to establish the origin of these signs, and to predict the future mental disorders of adoptees with these signs. The study is a part of the Finnish Adoptive Family Study of Schizophrenia. Genetic vulnerabilty indicators were studied by comparing MMPI (Minnesota Multiphasic Personality Inventory) subscales of high-risk adoptees (HR, biological mother with a diagnosis of schizophrenia spectrum disorder) and low-risk adoptees (LR, biological mother with no diagnosed schizophrenia spectrum disorder) in the sample of all adoptees (n = 182) and in the sample of initially mentally healthy adoptees (n = 136). The later mental health status of the initially mentally healthy adoptees (assessed with DSM-III-R criteria) was predicted by MMPI subscales during the 11-year follow-up. The origins of the vulnerability indicators were investigated by assessing gene-environment interaction using parental Communication Deviance (CD) as a measure of environmental risk (n = 99). The MMPI subscales Hostility, Hypomania, and Social Maladjustment (these scales indicate emotional unresponsiveness, avolition, decreased energy, and introversion) were found to be vulnerability indicators of schizophrenia spectrum disorders. Social Maladjustment developed under gene-environment interaction when the environmental risk was assessed by CD. Psychopathic Deviate (asociality) was found to be a predictor of any later mental health disorder of the adoptees. Genetic vulnerability to schizophrenia spectrum disorders, gene-environment interaction and later onset of psychiatric disorders were found to manifest in the adoptees' MMPI. These results suggest a need to use a combination of multiple methodologies in the screening of at-risk individuals and are useful in the clinical practice of preventive mental health care. / Tiivistelmä Skitsofreniaan sairastumisessa keskeisiä ovat perintö- ja ympäristötekijät sekä näiden yhdysvaikutus. Skitsofrenia kehittyy siten, että jo ennen sairauden puhkeamista on olemassa alttiutta ilmentäviä, sairautta ennakoivia prodromaali piirteitä. Tämän tutkimuksen tarkoituksena oli etsiä skitsofreniaspektrin häiriöihin sairastumiseen liittyviä haavoittuvuutta ilmentäviä merkkejä, selvittää kuinka nämä kehittyvät ja ennustaa niillä adoptiolasten myöhempiä mielenterveydenhäiriöitä. Tutkimus on osa suomalaista adoptiolapsiperhetutkimusta. Perinnöllistä haavoittuvuuden ilmenemistä tutkittiin vertailemalla riskiadoptiolasten (biologisella äidillä oli skitsofreniaspektrin häiriö) ja heidän verrokkiensa (biologisella äidillä ei ollut skitsofreniaspektrin häiriötä) MMPI (Minnesota Multiphasic Personality Inventory) testin osa-asteikkoja kaikkien adoptiolasten ryhmässä (n = 182) ja tutkimuksen aloitusvaiheessa psyykkisesti terveiden adoptiolasten ryhmässä (n = 136). Tutkimuksen aloitusvaiheessa psyykkisesti terveiden adoptiolasten MMPI testin osa-asteikoilla ennustettiin 11 vuoden seurannassa heidän DSM-III-R kriteerein arvioitua mielenterveyttään. Perimän ja perheympäristön (adoptiovanhempien kommunikaatiohäiriöt) yhdysvaikutuksella pyrittiin selittämään haavoittuvuutta ilmentävien piirteiden syntyä (n = 99). MMPI testin osa-asteikot Hostility, Hypomania ja osittain myös Social Maladjustment (astekot ilmentävät emotionaalisen vastavuoroisuuden puutetta, tahdottomuutta, energian puutetta ja sosiaalista vetäytyneisyyttä) osoittivat perinnöllistä haavoittuvuutta skitsofreniaspektrin häiriöihin. Social Maladjustment kehittyi perinnöllisen riskin ja adoptiovanhempien poikkeavan kommunikaation yhdysvaikutuksen seurauksena. Psychopathic Deviate (asosiaalinen käyttäytyminen) ennusti adoptiolasten myöhempää sairastumista mihin tahansa mielenterveydenhäiriöön. Perinnöllinen alttius skitsofreniaspektrin häiriöihin, perintö- ja ympäristötekijöiden yhdysvaikutus sekä myöhempi sairastuminen mielenterveyden häiriöihin ilmenivät MMPI testin tuloksissa. Tuloksia voidaan käytää hyväksi mielenterveydenhäiriöiden ennaltaehkäisyssä.

Based on the shortcomings of past research, the need for understanding and investigation of the general relationship between self-report measures and human figure drawings required understanding and investigation (Riethmiller & Handler, 1997b; Waehler, 1997) while utilising a quantitative, configural scoring approach. Riethmiller and Handler (1997a; 1997b) hypothesised that subjects have one of two typical approach styles to anxiety/stress that influences their execution of the Human Figure Drawing (HFD) Test: “Avoidance” or “Coping” as measured by composite scoring index clusters. They argue that these two approach styles had to be taken into account when investigating anxiety on the HFD Test. According to Handler and Reyher (1965) those who experience more intense anxiety typically rely on an “Avoidant” approach, while those with lower anxiety typically rely on a “Coping” approach. The “Coping” response is hypothesised to suggest good ego-strength, and the “Avoidant” response poor ego-strength. Handler and Reyher (1964; 1965; 1966) also argued that there are two sources of anxiety on projective drawings: internal and external sources of anxiety. They hypothesised that the “External” anxiety cluster (measured by utilising the car drawing) and self-report measures both assess ‘external’ anxiety. Using Handler’s (1967) HFD index scoring manual, this research therefore inve stigated the level of correlation of the two MMPI-2 anxiety scale scores with (a) the hypothesised Stress Approach HFD cluster scores, as well as with (b) the “External” anxiety cluster score, while the hypothesised Stress Approach HFD cluster scores were compared with the (c) MMPI-2 ego strength scale score. The results of the investigated relationships yielded non-significant correlations overall. The differences in nature of the two measurement instruments, and the potential weaknesses of this study, as two likely explanations for these correlations, are discussed. In the consideration of the differences of the two measurement instruments, the weaknesses of SR measures and criterion-related validity are discussed while self- attributed and implicit motives are contrasted with each other. Potential extraneous variables and possible truncated range are discussed as potential weaknesses of this study.

Despite a substantial expanse of literature addressing male sexual offending, the phenomenon of female sexual offending has only recently garnered empirical attention. While research remains nascent in nature, considerable advances have been made in the study of demographics, criminal characteristics, and typologies of female sexual offenders (FSOs). Similarities and differences between male and female sexual offenders have been the source of much speculation; however, hypotheses arising from this speculation have rarely been subjected to empirical scrutiny. Similarly, there has been limited examination of intra-group differences among FSOs. While myriad actuarial assessments have been developed for use with male offenders, similar measures for female offenders are practically non-existent. One notable exception is the Multiphasic Sex Inventory II (MSI II), an instrument with both male and female forms. The present study analyzed, compared, and contrasted the MSI II protocols of 300 male and female adult sex offenders.

The purpose of the present study was to study the relationship of MCMI-III clinical scales with MMPI-2 clusters in a chronic pain population. Data was obtained through assessment data (N = 242) from the Dallas Spinal Rehabilitation Center (DSRC), that included MMPI-2 and MCMI-III, as well as pre-and post-assessment information (n = 21) and follow-up questionnaires (n = 19). Subjects' age ranged from 18 to 64. Each patient had a primary diagnosis related to a back and/or a cervical injury, a chronic pain diagnosis, and often medical prescription dependency and/or addition. Each has experienced back pain in the lumbar region (L1 to L5) or cervical region (C1 to C7) for an average of 32 months. Patients with thoracic (mid-spine) and carpal tunnel pain were excluded from this study. A multivariate cluster analysis procedure was performed that yielded 3 homogeneous female MMPI-2 clusters and 4 MMPI-2 homogeneous male clusters. Seven multiple regression analyses were performed to determine which MCMI-III clinical scales predicted cluster membership in the MMPI-2 clusters. Results indicated that MCMI-III clinical scales "7" Compulsive, "X" Validity and "C" Borderline were predictors for membership in the male MMPI-2 clusters. Membership in the female MMPI-2 clusters were predicted by MCMI-III clinical scales "4" Histrionic, "T" Drug Dependence and "2A" Avoidant. Nineteen pre-and post-MCMI-IIIs were analyzed for change after participants completed the six-week pain management program. Paired-sample t-tests were performed on these data and revealed that significant change was noted on 10 MCMI-III clinical scales. Follow-up data questionnaires were available on these same individuals. Results from a correlation analysis indicated that patients who reported having supportive relationships with their spouse and family and a secure source of income report better quality of sleep, better mood, are able to relax and are believe that they are able to manage their pain. Participants who were able to relax and remain calm report better quality of sleep, exercise frequently, report better quality of mood and believe that they will return to work soon. Findings from this study suggest that rather than using the MCMI-III as a diagnostic tool, a more efficient use of this instrument would be to understand maladaptive coping styles that may be present under stressful situations. This study's findings suggest that pain treatment program staff could utilize follow up information, as well as diagnostic information about coping strategies that might appear under stress, to shape interventions. Future research might focus on investigation of factors that predict both improvement and program failure, especially those present at initial intake.

The purpose of this study was to investigate the relationship of the psychological sex role of a person making sociometric nominations to the psychological sex role of such persons nominated. It was hypothesized that similar psychological and biological sexed persons would choose each other as friends and that similar psychological but opposite biological sexed persons would reject each other as non-friends.

The problem of this study was to determine if juvenile delinquents who commit auto theft without an accomplice differ significantly in certain characteristics from those who commit such thefts with one of more confederates. The characteristics investigated were: (1) scores made on individual scales of the Minnesota Multiphasic Personality Inventory and (2) intellectual ability as measured by the California Short-Form Test of Mental Maturity. Furthermore, the same characteristics were examined to determine if a significant difference existed between each of the groups of juvenile delinquents and a group of juveniles who did not have a record of delinquency and attended Sunday School classes regularly.