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Group psychotherapy is the most widely utilized treatment modality for convicted sex offenders, and the therapeutic alliance is considered a fundamental concept in virtually all applications of psychotherapy. However, empirical examination of how the therapeutic alliance impacts upon treatment effectiveness for sex offenders has been neglected. In a prospective design, a sample of 95 consecutive admissions to an inpatient treatment program for convicted adult male sex offenders was studied with regard to their experience of the therapeutic alliance with treatment staff, with their copatients, and with the overall treatment program. Patients of the Phoenix Program (Alberta Hospital Edmonton) rated their sense of alliance at monthly intervals. The therapists who worked with them (n = 21) also completed monthly evaluations of their own emotional responses toward these same patients. Pre- to post-treatment comparisons on personality tests, interpersonal distress, and interpersonal functioning showed a number of statistically significant changes consistent with treatment goals. Patients self-report over time in treatment showed a gradual, consistent increase of large effect size on all three alliance targets. Sex offenders in this sample were able to experience positive alliance with therapists and peers and the sense of alliance was shown to grow stronger over time. Staff ratings revealed that positive and negative affect increased as patients time in treatment increased. Significant associations between patient-rated alliance and outcome were found to be positive and in desired directions. The growth rate in alliance toward therapists was positively and significantly associated with the growth rate of conflict within oneself among female therapists. Male therapists also reported significant growth in conflict within oneself but this was independent of patient-rated alliance growth rates. Thus, female therapists experienced heightened affect in the face of greater patient alliance, while male therapists also experienced heightened affect but for reasons unrelated to patient alliance. There was virtually no reduction in negative affect toward patients despite moderate increases in positive affect toward patients. This study represents an important endorsement of a treatment model that seeks to improve general adjustment and ameliorate risk factors associated with recidivism, via positive changes in interpersonal relationships. / Psychiatry

In this research, Bayesian two-stage D-D optimal designs for mixture experiments with or without process variables under model uncertainty are developed. A Bayesian optimality criterion is used in the first stage to minimize the determinant of the posterior variances of the parameters. The second stage design is then generated according to an optimality procedure that collaborates with the improved model from first stage data. Our results show that the Bayesian two-stage D-D optimal design is more efficient than both the Bayesian one-stage D-optimal design and the non-Bayesian one-stage D-optimal design in most cases. We also use simulations to investigate the ratio between the sample sizes for two stages and to observe least sample size for the first stage. On the other hand, we discuss D-optimal second or higher order designs, and show that Ds-optimal designs are a reasonable alternative to D-optimal designs. / Ph. D.

Pultrusão é um de vários processos de fabricação de compósitos poliméricos. Seu princípio de funcionamento envolve a utilização de um conjunto de fibras de reforço, impregnadas previamente por uma resina polimérica termorrígida, que percorre o interior de uma matriz aquecida a fim curar a resina e dar o formato a um perfil sólido. Muitas variáveis de processo, tais como a temperatura das zonas de aquecimento sobre a matriz, a velocidade de tracionamento, a impregnação das fibras, a viscosidade da resina, entre outras, afetam a eficiência do processo assim como a qualidade e o desempenho dos compósitos. Neste estudo, foi investigada a influência do teor de fibra de vidro, do teor de carbonato de cálcio e da temperatura do reservatório de resina nas propriedades mecânicas, como a resistência à tração, o módulo de elasticidade, o alongamento até a ruptura e a dureza de barras sólidas circulares que foram fabricadas utilizando uma resina poliéster insaturada e um único peróxido orgânico. Foi constatado que o processo de pultrusão pode ser realizado utilizando um único iniciador de reação. Além disto, os resultados mostraram que a temperatura do reservatório de resina, o teor de carbonato de cálcio e o teor de fibra de vidro influenciaram de forma significativa nas propriedades das barras pultrudadas. Por fim, este estudo mostrou que é possível melhorar as características destes compósitos e, desta forma, desenvolver materiais que apresentem melhor qualidade e desempenho. / Pultrusion is one of several manufacturing processes of polymer composites. Its operating principle involves the use of a set of reinforcing fibers pre-impregnated with a thermoset resin which run through the interior of a heated die in order to cure the resin and to form a solid profile. Many processing variables such as die temperature, pulling speed, fiber impregnation, resin viscosity, among others, affect the process efficiency as well as the quality and performance of the pultruded composites. In this research, the influence of the glass fiber content, calcium carbonate content and the temperature of the resin bath on the mechanical properties, such as tensile strength, elastic modulus, elongation at break and superficial hardness of solid rods made with an unsaturated polyester resin and a single organic peroxide were investigated. It was observed that pultrusion process can be carried out using a single reaction initiator. In addition, the results showed that the temperature of the resin bath, the calcium carbonate and the glass fiber content have influenced significantly in the properties of the solid rods. Finally, this study showed that it is possible to improve the characteristics of such composites and, therefore, to develop materials that have good quality and performance.

PROBLEM - The bobbin friction stir welding (BFSW) process has potential benefits for welding thin sheet aluminium alloy. The main benefits of friction stir welding over conventional thermal welding processes are minimisation of energy usage, no need for consumables, potential for good weld quality without porosity, no fumes, minimal adverse environmental effects (green), minimal waste (lean), and reduced threats to personal health and safety. The BFSW process has further advantages over conventional friction stir welding (CFSW) in the reduction of welding forces, faster welding, and less fixturing. It is especially attractive to industries that join thin sheet material, e.g. boat-building. The industrial need for this project arose from the desire to apply the technology at a ship manufacturing company, INCAT located in Hobart, Tasmania, Australia. However there are peculiar difficulties with the specific grade of material used in this industry, namely thin sheet aluminium Al6082-T6. Early efforts with a portable friction stir welding machine identified the process to have low repeatability and reproducibility, i.e. process-instability. There are a large number of process variables and situational factors that affect weld quality, and many of these are covert. This is also the reason for divergent recommendations in the literature for process settings. PURPOSE - The main purpose of this research was to identify covert variables and better understand their potentially adverse effects on weld quality. Therefore, this thesis investigated the hidden variables and their interactions. Developing this knowledge is a necessity for making reliable and repeatable welds for industrial application. APPROACH - An explorative approach that focused on the functional perspective was taken. An extensive empirical testing programme was undertaken to identify the variables and their effects. In the process a force platform and BFSW tools were designed and built. A variety of machine platforms were used, namely portable friction stir welding, manual milling machine and computer numerical control (CNC) milling machine. The trials were grouped into 14 test plans. These are tool shoulder gap, spindle and travel speed, tool features, machines, tool fixation, machinery, welding direction, plate size (width and dimension), support insulation, tool materials, substrate properties and fixation. For the welded plates besides visual inspection of the weld, current, force, and temperature were measured. The Fourier transform was used to analyse the frequency response of machines. Also the welded samples were tested to the maritime standards of Det Norske Veritas (DNV). A number of relationships of causality were identified whereby certain variables affected weld quality. A model was developed to represent the proposed causality using the IDEF0 systems engineering method. FINDINGS - From these trials six main variables have been identified. These are tool features, spindle speed, travel speed, shoulder gap compression, machine variability, tool and substrate fixation. A rigid system is required for a consistent weld results. Under this condition, full pin features (threads and flats) need to be used to balance the adverse effects of individual features. It has been shown that fabricated bobbin tools with sharp edges can cause cuts and digging thus this feature should be avoided. Additionally, the substrate should have continuous interaction with the tool so the shoulder interference needs to be fixed and well-controlled. It is found that the compression generated by the shoulder towards the substrate helps material grabbing for better tool-substrate interaction. It is also shown that tool entry causes ejection of material and hence an enduring mass deficit, which manifests as a characteristic tunnel defect. The new explanation of the formation, origin and location of this defect has been explained. Material transportation mechanisms within the weld have been elucidated. It is also found that the role of the travel speed is not only to control heat generation but also for replacing the deficit material. Additionally, heat supplied to the weld depends not only on thickness, but also the width of the plate. Different types of machine cause an interaction in the material flow through their controller strategies. Jerking motion can occur at a slow travel speed, which also alters the way material is being transported. The Fourier transform (FFT) has been used to identify the characteristics of good and bad BFSW welds. This has the potential to be expanded for real-time process control. IMPLICATIONS - Tool deflection and positioning, material flow and availability are identified as affecting weld quality through stated mechanisms. The impact is even more severe when involving thin-plate aluminium. For the industry to successfully adopt this technology the process typically needs tight control of shoulder gap, tool strength and stiffness, feature fabrication, substrate and tool fixation. Additionally spindle and travel speed need to be adjusted not only based on the type of materials and thickness, but also the width, type of machine and method of tool entry. ORIGINALITY - New data are presented, which lead to new insights into the welding mechanics, production settings, material transportation and weld defects for BFSW on thin sheet material. The conventional idea that the welding tool has a semi-steady interaction with the substrate is not supported. Instead the interaction is highly dynamic, and this materially affects the weld-quality, especially in the difficult-to-weld material under examination. Factors such as shoulder gap, tool and substrate fixation compliance and machine types emerge as variables that need to be given attention in the selection of process parameters. The causal relationships have been represented in a conceptual model using an IDEF0 system approach. This study has made several original contributions to the body of knowledge. First is the identification of previously hidden variables that effect weld formation for the fixed gap BFSW process. The second contribution is a new way of understanding the material transportation mechanics within the weld. This includes the flow around the pin in the plane of the weld, the vertical transportation of material up the pin, the formation of turbulent-like knit lines at the advancing side, and the formation of tunnel defects. Also included here is a new understanding of how material deficit arises at tool entry and exit, and from flash/chips, and how this contributes to the tunnel weld defect. In addition, new understandings of the role of feed rate have been identified. Related to the material transportation, the work has also identified the importance of an interference fit between the substrate and tool. A third contribution is the identification of the dynamic interaction between tool and substrate. This identifies the important role rigidity plays. Associated with this is the identification of frequency characteristics of the motors under load. The fourth contribution is identification of the specific process settings for the difficult-to-weld material of AL6082-T6. The fifth contribution is the development of a novel method of fabricating bobbin friction stir welding tools as embodied in a patent application.

With the continuing trend towards miniaturization, micro milling plays an increasingly important role in fabrication of freeform and high-accuracy micro parts or components directly and cost-effectively. The technology is in kinematics scaled down from the conventional milling, however, existing knowledge and experiences are limited and comprehensive studies on the micro tooling performance are essential and much needed particularly for the process planning and optimization. The cutting performance of micro tools is largely dependent on the dynamic performance of machine tools, tooling characteristics, work material properties and process conditions, and the latter three aspects will be focused in the study. The state of the art of micro milling technology with respect to the tooling performance has been critically reviewed, together with modelling work for performance prediction as well as metrology and instrumentation for the performance characterization. A novel 3D finite element method taking into account the geometry of a micro tool, including the tool diameter, rake angle, relief angle, cutting edge radius and helix angle, has been proposed for modelling and simulation of the micro milling process. Validation through well-designed micro milling trials demonstrates that the approach is capable of characterizing the milling process effectively. With the support of FEM simulation developed, the tooling geometrical effects, including those from helix angle, rake angle and cutting edge radius with influences on cutting forces, tool stresses, tool temperatures, milling chip formation and temperatures have been comprehensively studied and compared for potential micro tool design and optimization purposes. In an effort to prolong the tool life and enhance the tooling efficiency, DLC and NCD coatings have been deposited on micro end mills by PE-CVD and HF-CVD processes respectively. Corresponding cutting performance of these coated tools have been assessed and compared with those of WC micro tools in both dry and wet cutting conditions so as for better understanding of the coating influence on micro tools. Furthermore, the cutting characteristics of the DLC coated and uncoated tools have been analysed through verified plane-strain simulations. The effects of coating friction coefficient, coating thickness and UCT have been determined and evaluated by design of simulation method. Mechanical, chemical and physical properties of a work material have a direct influence on its micro-machinability. Five most common engineering materials including Al 6061-T6, C101, AISI 1045, 304 and P20, have been experimentally investigated and their micro milling behaviours in terms of the cutting forces, tool wear, surface roughness, and micro-burr formation have been compared and characterized. Feed rate, cutting speed and axial depth of cut constitute the complete set of process variables and they have significant effects on the tooling performance. Fundamental understanding of their influences is essential for production engineers to determine optimum cutting parameters so as to achieve the maximum extension of the tool life. 3D FE-based simulations have been carried out to predict the process variable effects on the cutting forces, tool stresses, tool temperatures as well as micro milling chip formation and temperatures. Furthermore, experimental approach has been adopted for the surface roughness characterization. Suggestions on selecting practical cutting variables have been provided in light of the results obtained. Conclusions with respect to the holistic investigation on the tooling performance in micro milling have been drawn based on the research objectives achieved. Recommendations for future work have been pointed out particularly for further future research in the research area.

Pultrusão é um de vários processos de fabricação de compósitos poliméricos. Seu princípio de funcionamento envolve a utilização de um conjunto de fibras de reforço, impregnadas previamente por uma resina polimérica termorrígida, que percorre o interior de uma matriz aquecida a fim curar a resina e dar o formato a um perfil sólido. Muitas variáveis de processo, tais como a temperatura das zonas de aquecimento sobre a matriz, a velocidade de tracionamento, a impregnação das fibras, a viscosidade da resina, entre outras, afetam a eficiência do processo assim como a qualidade e o desempenho dos compósitos. Neste estudo, foi investigada a influência do teor de fibra de vidro, do teor de carbonato de cálcio e da temperatura do reservatório de resina nas propriedades mecânicas, como a resistência à tração, o módulo de elasticidade, o alongamento até a ruptura e a dureza de barras sólidas circulares que foram fabricadas utilizando uma resina poliéster insaturada e um único peróxido orgânico. Foi constatado que o processo de pultrusão pode ser realizado utilizando um único iniciador de reação. Além disto, os resultados mostraram que a temperatura do reservatório de resina, o teor de carbonato de cálcio e o teor de fibra de vidro influenciaram de forma significativa nas propriedades das barras pultrudadas. Por fim, este estudo mostrou que é possível melhorar as características destes compósitos e, desta forma, desenvolver materiais que apresentem melhor qualidade e desempenho. / Pultrusion is one of several manufacturing processes of polymer composites. Its operating principle involves the use of a set of reinforcing fibers pre-impregnated with a thermoset resin which run through the interior of a heated die in order to cure the resin and to form a solid profile. Many processing variables such as die temperature, pulling speed, fiber impregnation, resin viscosity, among others, affect the process efficiency as well as the quality and performance of the pultruded composites. In this research, the influence of the glass fiber content, calcium carbonate content and the temperature of the resin bath on the mechanical properties, such as tensile strength, elastic modulus, elongation at break and superficial hardness of solid rods made with an unsaturated polyester resin and a single organic peroxide were investigated. It was observed that pultrusion process can be carried out using a single reaction initiator. In addition, the results showed that the temperature of the resin bath, the calcium carbonate and the glass fiber content have influenced significantly in the properties of the solid rods. Finally, this study showed that it is possible to improve the characteristics of such composites and, therefore, to develop materials that have good quality and performance.

Pultrusão é um de vários processos de fabricação de compósitos poliméricos. Seu princípio de funcionamento envolve a utilização de um conjunto de fibras de reforço, impregnadas previamente por uma resina polimérica termorrígida, que percorre o interior de uma matriz aquecida a fim curar a resina e dar o formato a um perfil sólido. Muitas variáveis de processo, tais como a temperatura das zonas de aquecimento sobre a matriz, a velocidade de tracionamento, a impregnação das fibras, a viscosidade da resina, entre outras, afetam a eficiência do processo assim como a qualidade e o desempenho dos compósitos. Neste estudo, foi investigada a influência do teor de fibra de vidro, do teor de carbonato de cálcio e da temperatura do reservatório de resina nas propriedades mecânicas, como a resistência à tração, o módulo de elasticidade, o alongamento até a ruptura e a dureza de barras sólidas circulares que foram fabricadas utilizando uma resina poliéster insaturada e um único peróxido orgânico. Foi constatado que o processo de pultrusão pode ser realizado utilizando um único iniciador de reação. Além disto, os resultados mostraram que a temperatura do reservatório de resina, o teor de carbonato de cálcio e o teor de fibra de vidro influenciaram de forma significativa nas propriedades das barras pultrudadas. Por fim, este estudo mostrou que é possível melhorar as características destes compósitos e, desta forma, desenvolver materiais que apresentem melhor qualidade e desempenho. / Pultrusion is one of several manufacturing processes of polymer composites. Its operating principle involves the use of a set of reinforcing fibers pre-impregnated with a thermoset resin which run through the interior of a heated die in order to cure the resin and to form a solid profile. Many processing variables such as die temperature, pulling speed, fiber impregnation, resin viscosity, among others, affect the process efficiency as well as the quality and performance of the pultruded composites. In this research, the influence of the glass fiber content, calcium carbonate content and the temperature of the resin bath on the mechanical properties, such as tensile strength, elastic modulus, elongation at break and superficial hardness of solid rods made with an unsaturated polyester resin and a single organic peroxide were investigated. It was observed that pultrusion process can be carried out using a single reaction initiator. In addition, the results showed that the temperature of the resin bath, the calcium carbonate and the glass fiber content have influenced significantly in the properties of the solid rods. Finally, this study showed that it is possible to improve the characteristics of such composites and, therefore, to develop materials that have good quality and performance.

Background: Exposure tasks—where an individual confronts a feared stimulus or situation—are known to be a key element of the treatment for youth anxiety. However, optimal therapist behaviors during these exposure tasks and the specifics of how therapist should conduct exposure tasks have not been determined. The current study examined the relationship between therapist behaviors that (a) increased, (b) decreased or (c) maintained the youth’s anxiety during exposures and treatment outcomes. Methods: Participants were youth (N = 107) ages 7 to 17 who received cognitive behavioral therapy for anxiety. Youth and their primary caregiver(s) completed a diagnostic interview and self- and parent-report measures pre- and post-treatment. Exposure session videos were rated by observers trained to reliability on a coding system evaluating therapist behaviors. Hierarchical regression analyses examined the role of therapist behaviors in predicting treatment outcomes. Logistic regression assessed the ability of therapist behaviors to predict treatment responder status (i.e., being a treatment responder versus a non-responder). Exploratory analyses examined the relationship between the individual therapist behaviors (within the three overall categories of behaviors) and treatment outcomes. Results: Youth showed significant improvement over the course of treatment. The three categories of therapist behaviors used during exposure tasks (increase, decrease and maintain the youth’s anxiety) were not associated with treatment outcomes. Discussion: Findings indicate that so long as exposure tasks are conducted, the therapist behaviors during the exposures may not be as important for predicting outcomes. Clinical implications, study limitations, and future directions are discussed. / Psychology