Mit der vorliegenden Arbeit soll ein Beitrag geleistet werden, die lokalen Tragmechanismen eines Brückenhohlkastens im Bereich der Feldumlenkstellen (Feldlisenen) zu untersuchen und zu optimieren. Beim Entwurf einer Brücke gewinnt die Frage der Dauerhaftigkeit u.a. in Deutschland und der Schweiz eine immer zentralere und grössere Bedeutung. Dadurch können die laufenden Kosten reduziert werden, während ausserhalb dieser beiden Länder im Allgemeinen mehr Gewicht auf die rationelle Fertigung und die Kostenersparnis in der Bauphase gelegt werden. Die Dauerhaftigkeit von extern vorgespannten Brücken mit ihren relativ geringen Wartungs- und Unterhalts- bzw. Instandstellungskosten sind das Hauptargument für diese Bauweise. Bei Vorspannung ohne Verbund sind für externe Spannglieder grössere Verankerungskonstruktionen erforderlich, weil die Spannglieder nicht im Steg selbst, sondern mit einem Mindestabstand zum Steg in Lisenen vorgespannt werden müssen. Über diese Verankerungsstellen werden in Hohlkastenbrücken grosse Kräfte konzentriert in die Stege, Boden- und Fahrbahnplatten eingeleitet. Im Sinne von Gewichtsreduktion des Brückenbauwerks sollen die Feldlisenen möglichst schlank und Platz sparend ausgeführt werden. Nur durch eine sorgfältige Bemessung und Konstruktion der Verankerungs- und Umlenkstellen kann die Voraussetzung für sichere und dauerhafte Brückenbauwerke gewährleistet werden. Die Bruchsicherheit ist dadurch nicht beeinträchtigt. Von grösstem Interesse ist jedoch die Gebrauchstauglichkeit, das heisst die Rissbreiten mit Rücksicht auf Korrosionsschäden in der Bewehrung. Bei den ersten in Deutschland extern vorgespannten Brücken schlug Prof. Eibl für den Stahl III vor, die Spannungen von 240 N/mm2 auf 220 N/mm2 zu begrenzen. In der Richtlinie für externe Vorspannung von 1998 wurden die Spannungen weiter auf 180 N/mm2 reduziert. Um eine unkontrollierte Rissbildung in den hoch bewehrten Verankerungskonstruktionen zu verhindern, sind genaue Kenntnisse der Kraftflüsse und für die Praxis taugliche Bemessungsmodelle notwendig. Die Geometrie und die statische Berechnung der gewählten Umlenkkonstruktion müssen entsprechend gewichtet werden. In dieser Arbeit werden an zwei Vergleichsmodellen die lokalen Tragmechanismen einer extern vorgespannten Hohlkastenbrücke im Bereich der Feldumlenkstelle (Feldlisene) untersucht. Mit linear-elastischen und nichtlinearen numerischen Berechnungen wird abgeklärt, ob unter dem Ansatz einer Spannungserhöhung im Bewehrungsstahl auf 285 N/mm2, die Gebrauchstauglichkeit noch gewährleistet werden kann. Den Berechnungen wird eine Krafteinleitung von 2 x 3 MN mit Umlenkkräften von 4 x 0,64 MN zu Grunde gelegt. Die Berechnungen zeigen, dass das Ziel, mit einer Bewehrung von As = 3,35 % m2/m unter Gebrauchslasten keine Rissbreiten über 0,2 mm auftreten, erreicht werden kann. Die Berechnungen werden zudem an einem Brückenmodell im Massstab 1:1 in einem Belastungsversuch an der Empa in Dübendorf auf ihre Aussagekraft und Richtigkeit überprüft und bestätigt. / This present work which is aimed at contributing to local carrying mechanisms of a bridging box girder in the field of belt reversals, should be investigated and optimized. In designing a bridge the main concern is that of durability; especially in Germany and Switzerland, this is invariably acquiring a more central meaning. In this way recurring expenses can be reduced, whilst beyond these two countries in general more weight is laid on the rational manufacture and cost saving in the construction phases. The durability of externally pre-stressed bridges with their relatively low maintenance and service as well as repair costs are the main arguments for this method of construction. Larger anchorage construction is necessary for pre-tensioning external tensions. This is because the tensions are themselves not placed on the ligament itself, but must be pre-stressed in pilaster strips with a minimum distance. Over these anchorage locations immense energy is concentrated in the large box girder bridges, and thus induced in the ligament, ground and track supporting layers. As far as weight reduction of the bridging structure is concerned, the field pilaster strips should be designed as thin as possible and also be able to save space. Only through careful measuring and construction of the anchor and turning points can the requirements for safe and lasting bridge construction works be guaranteed. The bridge safety is thus not affected. However, the greatest interest is that of userfriendliness, i.e. the width of the fissure with consideration of corrosion damages in the armouring. At the first external pre-stressed bridge in Germany, Prof. Eibl suggested that for the steel III, stressing of 240/Nmm2 should be limited to 220 N/mm2. In the guideline for external pre-stressing of 1998, the tensions were further reduced to 180 N/mm2. In order to prevent an uncontrolled crack formation in the highly armoured anchorage construction, concrete knowledge of the distribution of forces for the applicable measurement models is necessary. The geometry and the statistical calculation of the selected deflect construction must be weighed accordingly. In this project two comparative models were inspected, which tested the local load mechanism of an external pre-stressed box girder bridge in the field redirecting area. With linear elasticity and numerical calculations it is possible to clarify if the serviceability can be allowed under the accretion of a stress increase in the armouring steel to 285 N/mm2. The calculations are based on a load transmission of 2 x 3 MN with a deviation force of 4 x 0,64 MN. The calculations will have a force transmission of 2 x 3 MN with turning forces of 4 x 0.64 MN forming the basis. The calculations portray that the goal to avoid any fissures over 0,2 mm can be achieved, with an armoring of As = 3,35 % m2/m under the service load. Additionally, the calculations will be assessed of their validity and accuracy on a scale of 1:1 in a loading test at the EMPA (the Swiss Federal Laboratories for Materials Testing and Research) in Dübendorf and be therefore confirmed.

Aim: The aim of this study was to identify and interpret former criminal delinquents experiences of what internal, social and structual factors are contingent on the process of change in offending. Method: A qualitative method was used with a hermeneutic approach. A qualitative inquiry was conducted through three semi-structured life story interviews with former criminal delinquents working on an organization that specifically strives to help delinquents to desist from crime.  The mode of analysis utilized in this study was the concept of turning points and a life course perspective which are useful tools in understanding the crucial parts of the processes and factors in the desistance process. Results: The results identified twelve sub-interpretations which were distilled into three over-arching interpretations which lead to the following singular conceptual interpretation: Creating preconditions to promote reintegration and readaptation to society is viewed as important to successfully desist from crime, which, in turn, depends on three sets of factors: cognitive transformation, individual’s social environment and structural/external factors which are interdependent on each other. Future research areas are suggested.

Syftet med studien var att undersöka hur känsla av sammanhang (KASAM) påverkas i vuxenlivet hos individer som farit illa i barndomen. Tidigare forskning tydliggör vilken omfattande problematik det kan vara. Vidare undersöker studien betydelsen av vändpunkter och motståndskraft för posttraumatiskt växande. Den kvalitativa metoden består av sex semistrukturerade intervjuer. Den kvantitativa metoden innefattar en webbenkät där 101 respondenter deltog. Antonovskys KASAM tillsammans med Mays existentialism och Honneths erkännandeteori lägger grunden för studiens teoretiska ansats. Resultatet visar att en förlust av grundtillit och egenvärde i barndomen leder till en svag känsla av sammanhang. Urvalsgruppens KASAM-värden var avsevärt lägre än normalbefolkningens, dock med hög meningsfullhet. I vuxenlivet tycks det viktigt att ta igen barndomens förluster. Samtalsstöd med ett salutogent synsätt kan kompensera för denna förlust. Det tillsammans med meningsskapande processer kan leda till posttraumatiskt växande. / The aim of this study was to examine how sense of coherence (SOC) is affected in adulthood in people who have suffered from adverse childhood experiences. Previous research indicate on how comprehensive of a problem this is. We also wanted to examine the impact of turning points and resilience for posttraumatic growth. The qualitative method consists of six semi- structured interviews. The quantitative method is composed of a web survey in which 101 respondents participated. Antonovsky's SOC together with May's existentialism and Honneth's theory of recognition lays the foundation for the study's theoretical approach. The result shows that a loss of basic trust and intrinsic value in childhood leads to a low sense of coherence. Participants SOC values was significantly lower than the normal population, however they scored high on meaningfulness. In adulthood it seems important to reclaim these losses from childhood. Different types of counseling with a salutogenic approach can make up for that loss. This, together with meaning-making, can lead to posttraumatic growth.

Adhesive wear occurs when small surfaces of the cutting tool due to friction are micro-welded to the chips and removed from the tool surface. A hypothesis as to whywelding occurs is that an electric potential field arises which initiates a chemical reaction and then welding of the work material and the tool takes place in the cuttingzone. The electric potential field results in a fluttering magnetic field, which in turngenerates electromagnetic issues. The waves should be around and above 1 MHz.The aim of this work is thus to investigate the presence of electromagnetic wavesfrom the cutting zone. The purpose is to compare sound and electromagnetic wavesduring the adhesive process. Previous research shows that the adhesive mechanism is a transient vibration thatmanifests itself as a cluster of waves with a stochastic duration, including a feedbacksystem restricted by the plastic deformation within the chip. Furthermore, the cutting speed is the most important cutting parameter in tool wear and the main wearmechanism at cutting speeds around 200 m/min is the adhesive wear. Several studies showed the emission of electromagnetic waves during plastic deformation ofmetals during tensile test. Frequency ranges for radiations are between 1 and 1000MHz. To investigate the hypothesis, axial turning was performed with a cutting speed190–200 (m/min) and one steel grade, SS2541 was used as a work material. Thedepth of cut and feed were set to 1 mm and 0,196 mm/rev. Detection and measurement of electromagnetic waves was performed with a spectrum analyzerMT8221B with four different signal receivers. A reference measurement was madewhen the turning machine was on without the workpiece being machined and then ameasurement was made during the turning process. The results of measurementsshowed a source of electromagnetic radiation within the frequency range 0–5 MHz.This result was achieved with copper plate as an antenna. To find out how signalsfrom acoustic emission and electromagnetic waves develop during the adhesive wearprocess, sound measurements were performed with microphones during the turningprocess. Results of sound measurement showed that the frequency at which adhesivewear occurs decreases and the amplitude increases as the insert wears. To be able toanalyze how electromagnetic radiation develops with the wear process, measurements must be performed in a shielded space from ambient disturbances, as in aworkshop there are many sources of noise that can affect the accuracy of the measurement. An antenna can be designed so that the measurement can take place asclose to the cutting zone as possible.

<p>Air intakes are a fundamental part of all high speed airbreathing propulsion concepts. The main purpose of an intake is to capture and compress freestream air for the engine. At hypersonic speeds, the intake’s surface and shock structure effectively slow the airflow through ram-air compression. In supersonic-combustion ramjets, the captured airflow remains supersonic and generates complicated shock structures. The design of these systems require careful evaluation of proposed operating conditions and relevant aerodynamic phenomena. The physics of these systems, such as the intake’s operability range, mass capture efficiency, back-pressure resiliency, and intake unstart margins are all open areas of research. </p> <p><br></p> <p>A high speed intake, dubbed the Indiana Intake Testbed, was developed for experimentation within the Boeing-AFOSR Mach 6 Quiet Tunnel at Purdue University. This inward-turning, mixed compression intake was developed from osculating axisymmetric theory and uses a streamtracing routine to create a shape-transitioned geometry. To account for boundary layer growth, a viscous correction was implemented on the intake’s compression surfaces. This comprehensive independent design code was pursued to generate an unrestricted geometry that satisfies academic inquiry into fluid dynamic interactions relevant to intakes. Additionally, the design code contains built-in analysis tools that are compared against CFD calculations and experimental data. </p> <p><br></p> <p>Two blockage models were constructed and outfitted with Kulite pressure transducers to detect possible intake start and unstart effects. Due to an error in the design code, the preliminary blockage models’ lower surfaces were oversized. The two intake models were tested over a freestream Reynolds number sweep, under noisy and quiet flow, at one non-zero angle of attack, and at a singular back-pressure condition. Back-pressure effects acted to unstart the intake and provide a comparison between forced-unstart and started states. The experimental campaign cataloged both tunnel starting and inlet starting conditions, which informed the design of the finalized model. The finalized model is presented herein. Future experiments to study isolator shock-trains, shock-wave boundary layer interactions, and possible instances of boundary layer transition on the intake’s compression surface are planned. </p>

Missbruk och beroende är idag ett utbrett samhällsproblem, på alla samhällsnivåer. Samtidigt som det finns ett stigma kring missbruk har antalet offentliga personer som berättar om sina erfarenheter av missbruk ökat. Studiens syfte har varit att genom kvalitativ tematisk textanalys analysera självbiografier av sju kända svenska män som berättar om sitt missbruk. Vi har undersökt hur droganvändning och dess orsaker skildras i kändisarnas självbiografier. Resultaten har kodats och tematiserats för att kunna besvara frågeställningen. Analysen innefattar förklaringsmodeller (samsjuklighet, självmedicinering, karriärmodell, skam och vändpunkt) som socialarbetare använder när de beskriver hur det kommer sig att vissa personer använder droger. Resultaten visar att berättelser om samsjuklighet, självmedicinering och tillfrisknande från droganvändning är snarlika, om än med individuella skillnader. Slutsatsen är att de ger en inblick i missbruk som kan vara till hjälp i att förstå och hjälpa personer som använder droger. / Addiction and drug dependency have become widespread social problems in all layers of society. While there is always a stigma around drug abuse, the number of public figures willing to share their experiences on the issue has increased. The purpose of the study was to analyse the autobiographies of seven famous Swedish men, writing about their addiction, using qualitative thematic text analysis. We have explored how we can gain a greater understanding of drug use and its causes, and how it is portrayed in autobiographies. The analysis contains selected explanatory models (comorbidity, self-medication, career model, shame and turning point) that social workers use when describing how and why a person is using drugs. Results have been coded and thematized in order to answer the questions at hand. The results show that stories on recovery from drug use are often quite similar, albeit with individual differences. The results give an insight into addiction which can help understanding and helping people affected by addiction.

Brytpunkten från gymnasiet kan förstås som ett avgörande vägskäl med ett överflöd avvalmöjligheter för ungdomar. Syftet med denna studie var att genom en kvantitativenkätundersökning kartlägga hur gymnasieelever i år tre på naturvetenskaps-,samhällsvetenskaps-, och ekonomiprogrammet i Stockholms län planerade och motiverade sittval inför tiden efter gymnasiet och att se hur detta skilde sig åt utifrån bakgrundsfaktorerna kön,etnicitet och bostadsort, samt att få en översikt för hur gymnasieeleverna upplevde brytpunktenfrån gymnasiet och hur de såg på sin egen handlingshorisont. Resultatet analyserades sedanutifrån Hodkinson &amp; Sparkes Careershipteori (1997, 2008) och visade att etnicitet såväl sombostadsort till viss del gjorde skillnad i hur elever planerade sina studie- och yrkesval. Valen attstudera vidare, arbeta eller ta sabbatsår motiverades främst av intresse, behov av paus frånstudier och att fundera på nästkommande val. Resultatet av studien visade även att majoritetenav respondenterna upplevde brytpunkten som halvt osäker men med en majoritet som vartillfredsställda med sina planerade val. Den främsta begränsningen vid det planerade valet somrespondenterna uppgav var betyg. / The turning point from upper secondary school can be understood as a definitive crossroadswith an abundance of choices for young people. The purpose of this study was to, through aquantitative survey, study how students in year three of the science, social sciences andeconomics program in Stockholm County planned and motivated their choice for the next phasein life, and to see how this differed based on the background factors gender, ethnicity and placeof residence, as well as to get an overview of how upper secondary school students experiencethe turning point from upper secondary school and how they see their own horizons for action.The results have then been analysed based on Hodkinson &amp; Sparkes Careership Theory (1997,2008). The results showed that ethnicity as well as the students' place of residence to someextent made a difference in how the students planned their educational and career choices. Thechoice to study, work or take a sabbatical was mainly motivated by interest, the need for a breakfrom studies and to further plan for their future. We also concluded from the results of the studythat the majority of respondents experienced high to some satisfaction with their plannedchoice. Grades were what the students experienced as most limiting in planning for their future.

Three-dimensional linear ray theory is used to investigate internal waves interacting with a Lamb-Chaplygin pancake vortex dipole. These interactions involve waves propagating in the same (co-propagating) and opposite (counter-propagating) horizontal directions as the dipole translation. Co-propagating internal waves in the vertical symmetry plane between the vortices of the dipole can approach critical levels where the wave energy is absorbed by the dipole or where the waves are overturned and possibly break. As wave breaking cannot be simulated with this linear model, changes in wave steepness are calculated to aid in estimating the onset of breaking. Counter-propagating internal waves in the vertical symmetry plane can experience horizontal and vertical reflections, including turning points similar to waves in two-dimensional steady shear. Wave capture is also a possible effect of either type of interaction, depending on initial wave properties and positioning relative to the vortex dipole. Away from the vertical symmetry plane, a spanwise converging (focusing) and diverging (defocusing) of wave energy is observed in co- and counter-propagating interactions as symmetric off-center rays interact with the dipole's individual vortices. Some off-center rays experience multiple horizontal refractions similar to wave trapping.

Ny lagstiftning har lagt fokus på den tociska naturen av bly som legeringselement I mässingsprodukter. Vattenförsörjningssystem är av största oro där misstänkt blyläckage från mässingsprodukter hotar människors hälsa, världen över. Denna studie har utförts i syfte att karaktärisera bearbetbarheten av blyfria mässingslegeringar för att förse industrin med nödvändig information och underlätta att ersätta dagens blyade alternativ. Karaktäriseringen har fokuserat på två specifika bearbetningsprocesser, nämligen svarvning och borrning där intresset har legat hos skärkraftsgenerering och spånbildning. Svarvtesterna riktade sig mot att jämföra tre olika legeringar, CW511L, AquaNordicÒ och CW625N. De två förstnämnda är blyfria och CW625N är en medelblyhaltig mässingslegering. Borrtesterna riktade sig mot att karaktärisera vilken effekt borrgeometrier har på skärkraftsgenerering och spånbildning. Huvudfokus lades på inverkan av spånvinkel och borrdiameter. Borrtesterna utfördes endast på AquaNordicÒ. Resultaten har visat att, signifikant högre skärkrafter genereras vid svarvning av blyfria legeringar jämfört med blyfria. Det fanns emellertid ingen signifikant skillnad mellan de båda blyfria legeringarna avseende skärkrafter, medan spånbildning förbättrades för AquaNordicÒ . Borrtesterna har å andra sidan visat att bearbetningen hos den blyfria AquaNordicÒ -legeringen kan förbättras genom att öka på spånvinkeln och minska borrdiameter. Baserat på resultaten från det här avhandlingsarbetet har man dragit slutsatsen att bearbetningen av blyfria mässingslegeringar är tillräckligt bra för att kunna antas av industrin. Förbättring är dock nödvändig för att ersätta de blyeade alternativen helt. / Recent legislation has put focus on the toxic nature of lead as an alloying element in brass products. Watersupply systems are of biggest concern where suspected lead leakages from brass products are threatening human health. A comprehensive study has been conducted in order to characterize the machinability of lead-free brass alloys to provide the industry with necessary information to assist a replacement of the leaded alternatives. The characterization has focused on two particular machining processes, namely turning and drilling and has been based on cutting force generation and chip formation. While the turning tests aimed to characterize the machinability by comparing two lead-free alloys (CW511L and AquaNordic®) with a leaded alloy (CW625N), drilling tests aimed to characterize machinability of the lead-free AquaNordic® alloy particularly, with the main focus put on the impact of tool geometry on machinability. The results have shown that significantly higher cutting forces are generated during turning of lead-free alloys as compared to the leaded. There was, however, no significant difference between the two lead-free alloys regarding cutting forces while chip formation is improved for AquaNordic®. Drilling tests have shown that the machinability of the lead-free AquaNordic® alloy can be improved by increasing the tool rake angle and decreasing tool diameter. Based on the results from this thesis work, it has been concluded that the machinability of lead-free brass alloys is sufficiently good to be able to be adopted by the industry. However, improvement is necessary inorder to fulfill the requirement needed to replace the leaded alternatives.

Brottsligheten i Sverige har ökat. Två av fem individer återfaller i brott efter frigivning. De individer som lever i utanförskap och kriminalitet är i en utsatt position. Flertalet av kriminalvårdens klienter har behov av insatser från olika verksamheter för att klara sig från återfall i kriminalitet. Syftet med studien är att få en djupare förståelse om vad före detta kriminella anser har varit betydelsefullt i deras process att lämna sin kriminella livsstil. Syftet är även att belysa vilken inverkan kriminalvården och socialtjänstens insatser har utgjort i denna process. De frågeställningar som studien ämnar besvara är: Vad har varit betydelsefullt för att kunna lämna den kriminella livsstilen? Vilken betydelse har insatser från kriminalvården utgjort i processen att lämna den kriminella livsstilen? Vilken betydelse har insatser från socialtjänsten utgjort i processen att lämna den kriminella livsstilen? För att besvara dessa frågor har vi använt oss av en kvalitativ ansats. Åtta semistrukturerade intervjuer har genomförts med medlemmar från KRIS och X-cons. Resultatet har analyserats utifrån teorin om sociala band samt tidigare forskning inom den valda studiens område. Det informanterna har uppgett som mest betydelsefullt är att känna ett sammanhang och meningsfullhet till sådant som sysselsättning, fritid och sociala relationer. Det som också har haft betydelse är de vändpunkter som informanterna har kommit i kontakt med. Dessa har varit sådant som fängelsestraff, försämrad hälsa, kontakt med föreningar och insatser från kriminalvården och socialtjänsten som sedan lett dem till insikt och möjlighet till förändring av deras livssituation. / Crime in Sweden has increased. Two out of five individuals reoffend after release from prison. Those individuals who are living in alienation and crime are in a vulnerable position. Most of the prison service and probation clients are in need of support from various authorities in order to desist from crime. The aim of this study is to gain a deeper understanding of what ex-criminals think has been important in their process to leave their criminal lifestyle. It also aims to view the impact of prison service and probation and social services support in this process. The questions which the study intends to answer are: What has been important to be able to leave the criminal lifestyle? How important has the efforts of the prison and probation service been in the process of leaving the criminal lifestyle? How important has the efforts of social services been in the process of leaving the criminal lifestyle? To answer these questions, we used a qualitative approach. Eight semi-structurerd interviews were conducted with members of KRIS and X-cons. The results have been analyzed according to the theory of social bonds and previous research of the selected study field. The informants have indicated that the most important factor is to feel a connection and meaningfulness such as employment, leisure and social relationships. What also played an important role were the turning points that the informants have come in contact with. These have been such as a prison sentance, impaired health, contact with organizations and efforts of prison and probation service and social services which then led them to the knowledge and ability to change their lives.