The purpose with this studie was to examine how individuals with experience of a long-term drugabuse describe their transformationprocess, and if this process has contributed to a change in their selfdescription. The studie was delimit to examine the transformationprocess, not in relation to what sort of abuse the informants had, or in relation to gender. The studie anwered questions concerning motivation to stop abusing, how the informants started the drugcareer, and how life as an abuser is described. In the studie qualitative method was used, five semi-structured interviewes were made with individuals who had a long-term addiction in the past. Symbolic Interactionism was the theoretical frame of referense that was used for analyse. Results showed that the description of the turningpoint either was as one specific event, or like a process connected to kumulative treatement experiences, and to other experienses described as positive. Results has also shown that the transformationprocess requiers time, and that it takes place both as a socialisation process and as an inner personal develpment. Important factors that affected the development was the relation to other human beeings, to have an onest relation to oneself, to participate in fellowships, personal sucess, to achieve a positive change in the view of themselves.

Silicon-on-insulator (SOI) technology has become increasingly attractive because of the strong light confinement, which significantly reduces the footprint of the photonic components, and the possibility of monolithically integrating advanced photonic waveguide circuits with complex electronic circuits, which may reduce the cost of photonic integrated circuits by mass production. This thesis is dedicated to numerical simulation and experimental performance measurement of passive SOI waveguide devices. The thesis consists of two main parts. In the first part, SOI curved waveguide and corner turning mirror are studied. Propagation losses of the SOI waveguide devices are accurately measured using a Fabry-Perot interference method. Our measurements verify that the SOI corner turning mirror structures can not only significantly reduce the footprint size, but also reduce the access loss by replacing the curved sections in any SOI planar lightwave circuit systems. In the second part, an optical 90o hybrid based on 4 × 4 multimode interference (MMI) coupler is studied. Its quadrature phase behavior is verified by both numerical simulations and experimental measurements.

Hard turning of difficult-to-cut materials is an economical method of machining components with high surface quality and mechanical performance. Conventionally in the machining industry, generating a component from raw goods includes a casting or forging process, rough machining, heat treatment to a desired hardness, and then finished-machining through a grinding process. Given the relative disadvantages of grinding, which include high specific energy consumption and low material removal rates, a newer technology has been introduced; hard turning. After the heat treatment of a cast part (generally in a range of 50-65 HRC), hard turning allows for immediate finished-machining. Hard turning reduces the production time, sequence, cost, and energy consumed. In addition, dry machining offsets environmental concerns associated with the use of coolant in grinding operations as well as other common turning operations. Higher specific forces and temperatures in the contact area between the tool and workpiece lead to excessive tool wear. Generated tool wear affects the quality of the machined surface. Therefore, minimizing tool wear and consequently the generated surface quality become the status quo. Adverse effects associated with generated heat at the tool tip can be reduced by using cutting fluid or by continuously providing a fresh cutting edge. The latter method will be applied in this thesis. Rotary tool cutting involves a tool in the form of a disk that rotates about its axis. Different types of rotary tools have been developed, all with similar functional characteristics, however few are commercially available. Rotary tools can be classified as either driven or self-propelled. The former is provided rotational motion by an external source while the latter is rotated by the chip flow over the rake face of the tool. A prototype self-propelled rotary tool (SPRT) for hard turning was developed which provides economical benefits and affordability for the user. It was tested on a turret-type CNC lathe by machining AISI 4140 Steel that was heat treated to 54-56HRC and Grade 5 Titanium (Ti-6Al-4V). Carbide inserts with ISO designation RCMT 09 T3 00 (9.5mm diameter) were used during machining. Both the SPRT rotational speed and the workpiece surface roughness were measured. Also, chips were collected and analyzed for each of the cutting conditions. The same procedure was followed during machining with the same tool which was denied the ability to rotate, therefore simulating a fixed tool with identical cutting conditions. Comparisons were made between tool life, surface roughness, and chip formation for the fixed tool and SPRT. Tool rotational speed was also analyzed for the SPRT. In general, the designed and prototyped SPRT showed very good performance and validated the advantages of self-propelled rotary tools. A typical automotive component that is hard turned from difficult-to-cut materials is a transmission input shaft. These components demand high strength and wear resistance as they couple the vehicle‟s engine power to the transmission and remaining driveline. / UOIT

La motivació de la tesis deriva en el interès de la indústria aeronàutica a explotar, per mitjà d'un disseny adaptat, la utilització del gir d'esquerda per protegir els reforços situats davant una esquerda que s'està propagant en la xapa d'una estructura integral. L'objectiu principal és l'avaluació i predicció del gir d'esquerda en situacions de càrrega pròximes a Mode I, proporcionant una eina de modelització i un criteri confident. L'entorn industrial sota el qual s'ha realitzat aquest treball requereix una predicció ràpida del comportament estructural proporcionant informació útil als constructors. Per aquest motiu la predicció del gir d'esquerda s'ha investigat utilitzant la teoria linear elàstica de la mecànica de la fractura (LEFM) i l'anàlisi amb elements finits (FEA).Durant aquest treball s'ha demostrat la importància i necessitat de caracteritzar el camp de tensions a la punta de l'esquerda amb el factor d'intensitat de tensió (SIF) conjuntament amb un segon paràmetre. La tensió uniforme, no singular, normal a la línea de l'esquerda i dependent en la geometria i càrrega de la proveta, es a dir la tensió T, ha estat seleccionada com a segon paràmetre per dur a terme les prediccions del gir d'esquerda.El criteri més desenvolupat per predir el gir d'esquerda en situacions pròximes a Mode I és el proposat per Buczek, Herakovich, Boone et al., anomenat WEFO en la tesis. Aquest combina el criteri de tensió principal màxima amb la tensió T i considera efectes d'anisotropia. LEFM s'ha utilitzat també en la predicció del gir d'esquerda sota càrregues quasi estàtiques controlant en tot moment la plastificació del lligament.En la investigació d'eines de modelització/simulació s'ha tingut en compte les capacitats d'aquestes en el camp de la mecànica de la fractura, de disseny, d'implementació, així com la complexitat d'ús. Tot i que hi ha un gran ventall de Softwares que compleixen els requeriments assenyalats, només aquells que es trobaven a l'abast de l'autor s'han analitzat. StressCheck ha estat escollit com a resultat de la investigació. L'avaluació de la propagació de l'esquerda en provetes compactes en tensió (CT) i en provetes amb dos elements reforçants (2SP) sota els règims de Paris i Forman ha estat satisfactòria.Un pas important ha estat la implementació de la capacitat d'extracció de la tensió T. La demostració de la fiabilitat en el seu càlcul s'ha demostrat mitjançant resultats en la literatura i càlculs analítics en provetes de doble biga en volada (DCB). Un aspecte a tenir en compte és la importància en realitzar anàlisis no linears geomètrics pel càlcul del SIF i la tensió T.Prediccions en la trajectòria de l'esquerda s'han realitzat en base amb els resultats obtinguts en l'estudi de modelització. La millor trajectòria s'ha predit per mitjà del criteri WEFO. No obstant, les diferents trajectòries obtingudes per una esquerda propagant-se en la direcció T-L o L-T no són comparables amb els resultats experimentals.Aquestes deficiències estan relacionades en la definició del punt d'inestabilitat de l'esquerda. Algunes referències posen de manifest que hi ha experiències on l'esquerda es comporta de forma estable tot i mostrar T > 0. Per un altre banda, els criteris WEF i WEFO defineixen la inestabilitat dependent d'una distancia específica del material, rc. Però la seva definició no és única i no existeix cap acord sobre el seu càlcul.L'autor proposa un criteri derivat dels criteris existents i basant-se en els assajos, simulacions i resultats obtinguts. Aquest deriva del treball de Pettit i la tensió T normalitzada, TR, proposada per Pook. La fiabilitat d'aquest criteri es demostra amb la proveta DCB. Les prediccions de la trajectòria de l'esquerda en la proveta cruciforme no són tant satisfactòries. Tot i així, s'ha d'accentuar que el criteri desenvolupat proporciona la predicció més acurada. / The motivation of this thesis started from the interest of aeronautical industry to exploit the utilization of crack turning to protect stiffeners in front of an approaching skin-crack in integral structures by a tailored design. The main objective was to assess and predict crack turning under nearly Mode I situations on structures that reproduce aeronautical conditions by providing a modelling tool and a reliable criterion. The industrial environmental in which this work has been carried out requires a fast prediction of the structural behaviour to provide useful inputs to aircraft designers. It is for this reason that the crack turning prediction was investigated by means of LEFM and FEA. During this work it has been shown the importance and necessity of a second parameter for the characterisation of the stress field at the crack tip besides the SIF. Among the different proposed second parameters, the uniform non-singular stress, normal to the crack line and dependent on the type of loading and specimen geometry, i.e. the T-stress, was selected for crack turning predictions due to both calculation simplicity and its independence of the crack tip distance. The most developed criterion for crack turning predictions near Mode I loading is the criterion proposed by Buczek, Herakovich and Boone et al., called the WEFO-criterion. This is the Maximal Principal Stress criterion implemented with the T-stress and taking into account anisotropic effects. A challenge of this thesis was to overcome the lack of prediction on crack turning provided by this last criterion.Although the validity of LEFM is restricted, it was applied for the prediction of crack turning for quasi-static loading while paying attention to possible plastification. A screening of existent commercial and non commercial tools was carried out in respect to their fracture mechanics capabilities, their design abilities, implementation as well as their complexity. Although, there are many software possibilities, only those within the reach of the author were evaluated. This resulted in the selection of the commercial tool StressCheck®. The assessment of crack propagation on compact tension and two stringer specimens governed by the Paris and Forman regimes was satisfactory compared with experimental results using the material data from simple standard specimens.An important step was the implementation of the T-stress extraction facility in the tool and the evidence of its reliability. The latter was proved by literature and analytical calculations on DCB specimens. An important finding was the importance to perform geometric non-linear analyses for computing SIF and T-stress to find values comparable with literature data and analytical calculations. Taking into account the results obtained on the modelling study, crack path predictions were performed. The best prediction by means of existing criteria was reached by the WEFO-criterion. Different crack paths were predicted for a crack propagating in T-L or L-T directions. However, these predictions were not satisfactorily reliable: the point in the crack path where crack turning should take place was not predicted adequately. Additionally, the crack paths were similar for T L and L-T directions. These deficiencies are related with the definition of the crack path instability. Some literature results have shown that in some experiences the crack behaved in a stable manner even if T > 0. Moreover, WEF and WEFO criteria define crack instability to be related with a material specific distance, rc, but, there is no agreement about its definition. Based on tests, simulation results and observations noted during this work, a compilation criterion was proposed. This is based on the work of Pettit and the normalised T-stress, TR, proposed by Pook. Its reliability was successfully proved on the DCB. The crack path predictions on the CFS were not as satisfactory. But even at its worst the developed criterion was the most accurate.

This thesis work was performed at AB Sandvik Coromant and aimed to enhance the knowledge about the relationships between the performance of TiN and TiAlN-coated cutting tools in metal turning and their mechanical and chemical properties. Measurements of coating material properties and turning wear tests in annealed tool steel Sverker 21, stainless steel 316L, grey cast iron V314 and nodular cast iron SS0727 were performed. The cutting temperatures were estimated from FEM-simulations. To find the dominant wear mechanism and identify the properties that are most important for the resistance against that particular wear, a correlation analysis was performed together with a wear study using LOM, SEM and EDS. The results show that relations between cutting performance and mechanical properties and/or composition of the coatings can be established. The FEM-simulations suggested that the peak tool temperature was highest, ~750°C, for turning in 316L and lowest for turning in Sverker 21, ~300°C. Turning in cast iron resulted in temperatures around 500-550°C. A mechanism for the growth of the crater on inserts tested in stainless steel 316L is proposed. Wear due to thermo-mechanical load and adhesion are believed to be the dominating wear mechanisms. The performance of the tool showed a high correlation to the composition of the coatings, with a decreased tool life for higher Al-contents. The reason for this might lie in an increased brittleness of these coatings, accelerating formation of lateral cracks above the crater. Calculated ratios of bulk and shear modulus suggests an increased brittleness for higher Al-contents. A higher tendency to stick to the work piece material might also contribute to a decrease in tool life. An Increased Al-content could also drive the formation of c-AlN to h-AlN, causing even higher wear rates. The coatings with higher substrate bias showed an enhanced performance, even though the crack pattern was worsened for these variants. The reason for the enhanced performance seen for these variants might instead originate in an enhanced adhesion to the substrate. In the flank wear resistance test in Sverker 21 the Al-content proved to be important, with an improved performance for higher Al-contents. In contrast to the test in 316L, a change in bias or hardness had no effect on the performance in this test. Scratch patterns on the flank supports that an abrasive wear mechanism is present, but no correlation between hardness and tool life could be obtained. Either some other material property than hardness is of importance for the abrasive resistance in this test, or another wear mechanism, occurring simultaneously with abrasion, is the wear rate deciding. The second part of this thesis work was to evaluate the ability of a quantum mechanical computational method, density functional theory, to predict material properties. The method predicts the lattice parameters and bulk moduli in excellent agreement with experimental values. The method also well predicts other elastic properties, with results consistent with reference values. There seems to be a constant shift of about 50-100 GPa between the calculated elastic modulus and the experimentally measured values, probably originating in contributions from grain boundaries, texture, stresses and defects present in the real coatings, and possibly also in errors in the experimental method due to an influence from the substrate. The calculated hardness values did not follow the trend of an increased hardness for TiAlN compared to TiN, which is seen in experiments.

This is a qualitative study aiming to illuminate and gain better understanding of deliberate self-harm. The study has a narrative perspective and is based on three women’s life stories, focusing on a period when they had an active self-harming behaviour. The study examines what the participants experienced as important to the initiation and the cessation of the deliberate self-harm. It is also examining identity performances and turning points which can be discerned in the life stories. The analysis is based on theories of the narrative perspective and on Erving Goffman's dramaturgical perspective. Our conclusions are that the participants of the study at the time prior to the self-harming behaviour felt as outsiders, and that they lacked strategies for dealing with emotions. We also found that functional relationships had an important role for the participants to enable the cessation of the deliberate self-harming behaviour. At the time when the participants managed to end the self-harming behaviour, they all had developed more functional relationships and did not feel the same alienation. They also feel that they have a different identity now than they had during the period of deliberate self-harm.         Keywords: Deliberate self-harm, identity performances, turning points, narrative   Nyckelord: Självskadebeteende, identitetsuttryck, vändpunkter, narrativ

Vad är avgörande vändpunkter i psykoterapi? Detta är en kvalitativ studie av konfidenters upplevelser av avgörande ögonblick/vändpunkter. Studien utgår från konfidenternas upplevelser och beskrivning av dessa vändpunkter. Metoden är fenomenologisk och utgår ifrån EPP- metoden. Samtliga sex informanter har gått i terapi över 25 timmar och alla har gått i en psykodynamisk terapi. Resultatet visade inte på några avgörande ögonblick/vändpunkter i form av aha-upplevelser. Konfidenterna lyfte istället fram vändpunkter i form av insikter över tid. Två gemensamma drag trädde fram i materialet. Konfidenterna framhöll hur de med terapins hjälp fick syn på hur de suttit fast i mönster och försvar i sina tidiga objektrelationer. Konfidenterna framhöll också vikten av ett "eget rum" att möta sig själv tillsammans med terapeuten. / What is the crucial turning point in psychotherapy? This is a qualitative study of patients' experiences of the crucial moments/ turning points in their psychotherapy. This study examined patients' experiences and their description of these. The method is phenomenological and is called the EPP- method. The six informants have all attended more than 25 hours of therapy they have all attended psychodynamic therapy. The results revealed no crucial moments/ turning points such as "aha moment". Instead the patients emphasized turning points and insights over time. Two common features emerged in the material. The patients emphasized how they due to the therapy became aware of how they have been stuck in patterns and defense systems due to their early object relations. The patients also emphasized the importance of a "private room" of their own where they could meet themselves together with the therapist.

Studien handlar om processen som leder ut ur hemlöshet, och jämför personer med en psykisk funktionsnedsättning och personer utan. Uppsatsen bygger på kvalitativa intervjuer med nio personer som har lämnat hemlöshet och missbruk. Fokus för studien och intervjuerna har varit individens upplevelse av processen som leder ut ur hemlöshet. Fem av intervjupersonerna hade en psykisk funktionsnedsättning och fyra av intervjupersonerna hade ingen diagnos. Vi har använt oss av Helen Ebaughs (1988) exitteori för att tolka och tematisera resultatet. I analysen har vi utvecklat teorin utifrån resultatet, då teorin inte beskriver individer som lämnar rollen som hemlös. Processen som leder ut ur hemlöshet har sett olika ut för intervjupersonerna i studien men det har funnits gemensamma inslag. Processen har tagit tid, vilket har varit viktigt för individen för att lyckas etablera sig i den nya rollen. För intervjupersonerna har det varit centralt att tillfriskna från missbruk för att ta sig igenom processen som leder ut ur hemlöshet. I början av processen var det viktigt att få lugn och ro omkring sig och senare i processen att finna en meningsfull sysselsättning samt en ny umgängeskrets för att kunna etablera sig och känna trygghet i den nya rollen. För många har självhjälpsgrupper eller ideella föreningar varit en plattform för dessa aspekter. Många har uppgett att det varit svårt att bryta med tidigare bekanta som fortfarande var kvar i missbruk. En annan svårighet som har beskrivits var misstroende från myndigheters sida. Processen som leder ut ur hemlöshet har varit likartad för personer med eller utan en psykisk funktionsnedsättning. Skillnaden har bestått i den sista fasen, att bygga nytt, då det har varit viktigt för personer med en psykisk funktionsnedsättning att få förståelse och kunskap om samt professionell hjälp med sin funktionsnedsättning.

<p>The goal of this work is to develop a practical and comprehensive methodology to study the response and the stability of various delay differential equations (DDEs). The development of these new analysis techniques is motivated by the existence of delays in the governing equations of many physical systems such as turning and milling processes. </p><p>Delay differential equations appear in many models in science in engineering either as an intrinsic component (e.g. machining dynamics) or as a modeling decision (biology related dynamics). However, the infinite dimensionality of DDEs significantly complicates the resulting analysis from both an analytical and numerical perspective. Since the delay results in an infinite dimensional state-space, it is often necessary to use an approximate procedure to study DDEs and ascertain their stability.</p><p>Several approximate techniques appeared in literature to study the stability of DDEs. However, a large number of these techniques---such as D-subdivision, Cluster Treatment of Characteristic Roots and Continuous Time Approximation---are limited to autonomous DDEs. Moreover, the methods that are suitable for non-autonomous DDEs, e.g. the Semi-discretization approach, often result in a very large system of algebraic equations that can cause computational difficulties. Collocation-type methods, such as Chebyshev-collocation approach, have also been used to study DDEs. One major limitation of the conventional Chebyshev collocation approach is that it is strictly applicable to DDEs with continuous coefficients. An alternative approach that can handle DDEs with piecewise continuous coefficients is the Temporal Finite Element Analysis (TFEA). However, TFEA has only linear rates of convergence and is limited to h-convergence schemes. The limited rate of convergence in TFEA has prohibited its application to a wide class of DDEs such as DDEs with complicated coefficients or with distributed and multiple delays. </p><p>In this thesis, I develop a spectral element method for the stability analysis of DDEs. The spectral element method is a Galerkin-type approach that discretizes the infinite dimensional DDE into a finite set of algebraic equations (or a dynamic map). The stability of the system is then studied using the eigenvalues of the map. </p><p>In contrast to TFEA, the spectral element method was shown to have exponential rates of convergence and hp-refinement capabilities. Further, a comparison with the widely-used collocation methods showed that our approach can often yield higher rates of convergence. The higher rates of convergence of the developed approach enabled extending it to DDEs with multiple and distributed delays. I further extended this approach to calculating the periodic orbits of DDEs and their stability. </p><p>As an application of the methods developed in this thesis, I studied the stability of turning and milling models. For example, a distributed force model was proposed to characterize cutting forces in turning. The stability of the resulting delay integro-differential equation was studied using the methods developed in this study and they were shown to agree with practical observations. As another example, the stability of a milling process--- whose model contains piecewise coefficients---was investigated. The effect of multiple-flute engagement, which contributed to the complexity of the coefficients, was also investigated. The resulting stability charts revealed new stability observations in comparison to typical analysis methods. Specifically, I was able to show that unstable regions appear in what was deemed a stable region by prior analysis techniques.</p> / Dissertation

The chip formation process in machining is accompanied by heat generation. The heat generated influences both the workpiece physical properties as well as the cutting tool. High temperatures accelerate tool wear and thermal softening which are not desirable because they alter the accuracy of the machined surface and tool life. Many studies have been done to lower the heat generated in cutting. A first approach is to use a cutting fluid but its effectiveness is limited by its ability to penetrate between the tool and the chip. A second approach is to remove the heat generated through a cooling cycle as in interrupted cutting. The idea is either to translate a wide tool to the side as it moves forward relative to the workpiece, which allows the dissipation throughout the body of the tool or to use a cutting edge in the form of a disk that rotates about its principal axis. The latter, known as a rotary tool, provides a rest period for the cutting edge, thus enabling the edge to be cooled and a continuously fresh portion of the edge to be engaged with the workpiece. The rotary tool can be either driven by an external power source or self-propelled. This thesis focuses on the self-propelled rotary tool (SPRT) process for machining of difficult-to-machine material such as bearing steels, where tool life is of particular concern. Since the cutting temperatures are known to influence tool life significantly, the first task in this investigation involved developing a model to analyze heat transfer and temperature distribution in the cutting tool during SPRT turning of the hardened 52100 steel (58 HRC). Both rotary and equivalent fixed tool processes are compared in terms of cutting tool temperatures generated. The model is based on the moving heat source theory of conduction and employs the Finite Element Method (FEM) for its solution. The model is experimentally verified through measurement of the cutting temperature distribution using an Infra-Red imaging camera under different cutting conditions. Predicted and measured temperatures show good overall agreement when they are measured along the cutting edge and measured temperatures are up to 50??ower in rotary tool cutting than in fixed tool cutting under the same conditions.