Transition zones are changes in the track structure, detected by an abrupt deviationin track stiffness and/or differential settlements. One inevitable transition zone is thebridge approach. This study has investigated in this transition zone, adapted for highspeed,ballastless track. The aim was to observe the general behaviour of the transitionzone including its critical components, and to compare different measures, transitionconstructions, to manage with the eventual problems. A base model, called Nullmodel,was developed using the 3D finite element method to evaluate the behaviour of thetransition zone. Based on the Nullmodel, six comparative models have been created,including different types of transition constructions within the substructure. New forthis study is that it investigates the overall behaviour of the transition zone, and alsothe substitution of subballast in combination with approach blocks.For the general behaviour of the transition zone, the results have shown that theballastless track does not behave as a traditional ballasted track. Furthermore,the direction of travel affects the magnitude of different dynamical parameters.Comparing different transition constructions, replacing the subballast with ahydraulically bonded layer in combination with an approach block with cementbounded granular material is found to be the best alternative. Finally, the invertedapproach block is found to be an equally good, or better, mitigative measure incomparison with the regular approach block.

Bakgrund: Total höftplastik är en operation där en protes ersätter höftleden. Ingreppet genomförs alltmer i dagkirurgi. Rehabiliteringen sker i hemmet med uppföljningsbesök av fysioterapeut. Följsamhet till rehabilitering är viktigt för att återfå funktion. Insikt i patienters upplevelser av rehabilitering kan ge ny värdefull kunskap för fysioterapi med beteendemedicinsk inriktning. Syfte: Syftet med studien är att studera hur patienter som genomgått total höftplastik i dagkirurgi upplever följsamhet till postoperativ rehabilitering. Metod: Deskriptiv kvalitativ design med induktiv ansats. Sex patienter som genomgått total höftplastik i dagkirurgi inkluderades och deltog i individuella semistrukturerade intervjuer. En kvalitativ innehållsanalys tillämpades för att analysera data från intervjuerna. Resultat: Analysen resulterade i 15 underkategorier med följande fem huvudkategorier: Vikten av en bra start, Betydelsen av socialt stöd och vägledning, Funktion och resultat styr utförande, Betydelsen av personliga egenskaper och mentalitet, Träningsprogram underlättar hemträningen. Slutsats: Upplevelsen av följsamheten till rehabilitering efter total höftplastik i dagkirurgi utgörs av ett flertal individ- och omgivningsfaktorer såsom mentalitet, utfallsförväntningar, socialt stöd och väder. Resultat av denna studie tillför en ökad förståelse till bio-psyko-sociala upplevelser av följsamhet till rehabiliteringen efter dagkirurgisk total höftplastik i svensk kontext. / Background: Total hip arthroplasty is a surgery where the hip joint is replaced by a prosthesis. Nowadays the surgery is often carried out in day-surgery. The rehabilitation occurs at home with physiotherapeutic follow-up visits. Compliance to rehabilitation is important to regain function. Insight into patients’ experiences of rehabilitation can provide valuable new knowledge for physiotherapy with a behavioral medicine focus. Aim: To study how patients experience their compliance to rehabilitation after total hip arthroplasty in day-surgery. Method: Descriptive qualitative design with an inductive approach. Six patients who underwent total hip arthroplasty in day-surgery were included and participated in individual semi-structured interviews. A qualitative content analysis was applied to analyze data from the interviews. Results: The analysis resulted in 15 subcategories with the following five main categories: The importance of a good start, The significance of social support, Function and results control the performance, The meaning of personal characteristics and mentality, Exercise program facilitates the home rehabilitation. Conclusion: The experience of compliance to rehabilitation after total hip arthroplasty in day-surgery consists of several individual- and environmental factors such as mentality, outcome expectations, social support and weather. The result of this study expands the understanding of bio-psycho-social experiences of compliance to rehabilitation after total hip arthroplasty in day-surgery in a Swedish context.

This thesis is an investigation of how a modular on-track gantry system intendedfor arc-welding robots can be standardized by using the existing product portfolio ofon-track gantry systems of a company.The company in this thesis have chosen to be anonymous, and will be referred toas the company. The need for a standardized product is high, since robot solutionsis consistently becoming more prevalent in all industries year by year. They havethe ability to execute commands with precision for longer than any manual labourcould. To keep up with the demand for robot solution, the company is interestedin standardizing their current on-track gantry system to speed up their process.Standardizing is the process of developing and implementing specifications based onthe consensus of the views of firms, users, interest groups and governments. Thecompany currently customizes most of their on-track gantry systems but wants tostandardize this process.The purpose of this thesis is to propose and evaluate a standardized model of anon-track gantry system. This is done by dividing the work in three separate phases.One pertaining to collecting information about the on-track gantry. The followingphase involves processing the information and establishing a baseline for the model.The final phase is contains the creation of a new on-track gantry system that isconstructed from existing parts and and new parts and simulated regarding stressand frequency.The information that could be extracted from existing on-track gantry were anumber of parameters, such as stroke lengths, production costs, part numbers etc.From the information, a set of needs could also be established. Further, the infor-mation is processed by comparing how many different parts exists in the modules ofexisting on-track gantry. A decision is also done here with the help of two decisionanalyses, to choose the best existing gantry to base the standardized model on. Fi-nally, a proposed standardized model is constructed with a set 2 stroke lengths inz-direction, 1500 mm and 2000 mm and 3 stroke lengths in x-direction, 2000 mm,3000 mm and 4000 mm. The model also includes the option to choose whether anattached arc-welding robot is placed stiff in a position or if it should move the entireinterval in the z- and x-directions.In conclusion, the new proposed model is standardized due to there being a clearguideline for how the model is set up, what it can hold and the stroke lengths. / Den här tesen är en undersökning av hur ett modulärt on-track gantry system förbågsvetsrobotar kan standardiseras med hjälp av ett företags befintliga produktport-följ av gantry system för bågsvetsrobotar.Företaget har i denna avhandling valt att vara anonymt och kommer att benäm-nas företaget. Behovet av en standardiserad produkt är stort, eftersom robotlösningarständigt blir vanligare i alla branscher år för år. De har förmågan att utföra kom-mandon med precision under längre tid än vad manuellt arbete skulle kunna göra.För att hålla jämna steg med efterfrågan på robotlösningar är företaget intresserat avatt standardisera sitt nuvarande system med spårbundna gantry för att påskynda sinprocess. Standardisering är en process för att utveckla och genomföra specifikationersom bygger på en samsyn mellan företag, användare, intressegrupper och regeringar.Företaget anpassar för närvarande de flesta av sina gantry system på spåren, menvill standardisera denna process.Syftet med denna avhandling är att föreslå och utvärdera en standardiserad mod-ell av ett gantry system för spårbundna fordon. Detta görs genom att dela upp ar-betet i tre separata faser. En som gäller insamling av information om gantry. Denföljande fasen handlar om att bearbeta informationen och fastställa en grund förmodellen. Den sista fasen innehåller skapandet av ett nytt system för spårbundnagantry som konstrueras av befintliga delar och nya delar och simuleras med avseendepå belastning och frekvens.Den information som kunde utvinnas från befintliga spårbundna gantry var ettantal parametrar, såsom slaglängder, produktionskostnader, artikelnummer osv. Utifråninformationen kunde också en uppsättning behov fastställas. Vidare bearbetas in-formationen genom att jämföra hur många olika delar som finns i modulerna i debefintliga spårburna gantry. Här fattas också ett beslut med hjälp av två beslutsanal-yser för att välja den bästa befintliga gantry att basera den standardiserade modellenpå. Slutligen konstrueras en föreslagen standardiserad modell med två slaglängder iz-riktningen, 1500 mm och 2000 mm, och tre slaglängder i x-riktningen, 2000 mm,3000 mm och 4000 mm. Modellen innehåller också möjligheten att välja om enansluten bågsvetsrobot placeras styvt i en position eller om den ska förflytta sig helaintervallet i z- och x-riktningen.Sammanfattningsvis är den nya föreslagna modellen standardiserad tack vare attdet finns en tydlig riktlinje för hur modellen är uppbyggd, vad den kan hålla ochslaglängderna.

The PANDA experiment at FAIR is an antiproton experiment and it will offer unique possibilities for the study of hadron physics including hyperon physics. With the PANDA detector, it will be possible to exclusively reconstruct hyperon-antihyperon events. Hyperons are relatively long-lived particles (10−10s), which can travel for a distance of up to a few meters before decaying into their reconstructible decay products. In this project, I focus on the reaction p̅ p → Ξ̄+ Ξ− → Λ̅ π+ Λ π− → p̅ π+π+ p π− π−. The Ξ− (cascade) hyperons take a special role as they are the lightest hyperons to introduce a sequential decay topology, i.e., Ξ− → Λ π− → p π− π− (and c.c.). This constitutes a substantial challenge for the reconstruction algorithms. In this thesis, a Monte-Carlo simulation study of realistic track and event reconstruction of this Ξ̄+ Ξ− reaction in the region near the production threshold is done, and the event generation of the Ξ̄+ Ξ− reaction channel was performed by the EvtGen event generator in PandaRoot. For various realistic tracking algorithms, track and event reconstruction performance levels were investigated in PandaRoot.

With the introduction of high-speed trains over the past few years, as well as withan increase in traffic loads and volumes, the attractiveness and competitiveness ofthe railway transport system have increased. This leads to the need to develop newcost-effective ways in railway construction, providing an increase in the life cycle ofthe railway track and reducing the need for maintenance.In several European countries, Japan, and the USA, asphalt mixtures, also called“bituminous mixtures”, are used as such an alternative solution in both traditionalballasted and ballastless railway designs. International experience has shown thatbituminous mixtures have good technical characteristics and can meet many of therequirements of modern railway construction, especially when it comes to the useof asphalt materials in ballasted tracks. However, there is a lack of knowledge andexperience in using bituminous mixtures in railway construction in the northernregions and harsh winter conditions.In this thesis, the development of two- and three-dimensional models of ballastedrailway track with an asphalt sub-ballast layer is presented. The analysis of thestatic and dynamic characteristics of the whole model and the asphalt layer exposedto different temperatures is carried out using the finite element method (FEM) inthe COMSOL software. Simulation for all conditions is carried out with a trainspeed of 200 km/h. The relationship between various temperatures from 􀀀30 °Cto +30 °C and the stress-strain behaviour of the asphalt sub-ballast layer is alsodetermined. The results of the study show that both under the influence of lowand high temperatures, the stresses and strains in the asphalt layer are quite small.Besides, the use of asphalt sub-ballast in the track structure reduces deformationsand stresses acting on the subgrade surface.

The development of Discrete Element Model (DEM) of railway ballast for the purpose of studying the behavior of ballast particles during tamping is addressed in a simulation study, with the goal of optimizing the railroad tamping operation. A comprehensive literature review of applicability of DEM techniques in modeling the behavior of railway ballast is presented and its feasibility in studying the fundamental mechanisms that influence the outcome of railroad tamping process is analyzed. A Discrete Element Model of railway ballast is also developed and implemented using a commercially available DEM package: PFC3D. Selection and calibration of ballast parameters, such as inter-particle contact force laws, ballast material properties, and selection of particle shape are represented in detail in the model. Finally, a complete tamping simulation model is constructed with high degree of adjustability to allow control of all process parameters for achieving realistic output. The analysis shows that DEM is a highly valuable tool for studying railroad tamping operation. It has the capability to provide crucial and unprecedented insights into the process, facilitating not only the optimization of current tamping practices, but also the development of novel methods for achieving sustainable improvements in track stability after tamping in the future. Different ways of modeling particle shapes have been evaluated and it has been shown that while using spheres to represent irregular ballast particles in DEM provides immense gains in computational efficiency, spheres cannot intently capture all properties of irregularly shaped particles, and therefore should not be used to model railway ballast particles. Inter-particle and wall-particle contact forces are calculated using Hertzian contact mechanics for determining ballast dynamics during tamping. The results indicate that the model is able to accurately predict properties of granular assemblies of the railway ballast in different test cases. The developed model for simulating tamping operation on a half-track layout is expected to be extended in future studies for evaluating rail track settlement and stability, optimization of tamping process, and performance of different ballast gradations. / MS / Development of a virtual simulation model for the stone bed which forms the foundation of traditional rail track structures is discussed in this study for the purpose of improving a conventional railway maintenance practice called tamping. The stone bed, called ballast, is flexible and is susceptible to undesirable deformation due to the forces from train traffic on the rail tracks over their service time. Therefore, periodic restoration of track structure is performed by tamping to maintain the operational quality of the rail tracks and reduce the risk of train accidents. This simulation model is intended to accelerate the scientific development of the current tamping practices by providing unprecedented insight into the behavior of small stones which form the bulk of the ballast and obviating the requirement for costly physical experimentation. The nuances of the mechanical behavior of ballast have been examined by a comprehensive literature review and the selection of a modeling technique called Discrete Element Modeling (DEM) has been justified for modeling of ballast owing to its suitability in capturing intricate dynamics of ballast stones. The virtual simulation model which is developed as results of this work has been found to be extremely efficient in realistically predicting the outcome of tamping process for any set of conditions of interest. This implies that quality of the rail tracks after tamping can be studied for a variety of different test cases and most optimized set of tamping parameters which results in maximum track quality can be analyzed. However, it was observed that the accuracy of the results obtained from the simulation model is dependent on the level of detail which is used to input properties of the ballast into the model. Low level of detail results in less accurate results whereas a high level of detail takes an unreasonably long time to solve. Therefore, a compromise has to be made between accuracy and solution time while programming the simulation model, and additional work is required in the future to improve the solution speed of the model.

This thesis shows the advantages of simple models for analysis of railway operation. It presents two tools for infrastructure and timetable planning. It shows how the infrastructure can be analysed through fictive line designs, how the timetable can be treated as a variable and how delays can be used as performance measures. The thesis also gives examples of analyses of complex traffic situations through simulation experiments. Infrastructure configuration, timetable design and delays play important roles in the competitiveness of railway transportation. This is especially true on single-track lines where the run times and other timetable related parameters are severely restricted by crossings (train meetings). The first half of this thesis focuses on the crossing time, i.e. the time loss that occurs in crossing situations. A simplified analytical model, SAMFOST, has been developed to calculate the crossing time as a function of infrastructure configuration, vehicle properties, timetable and delays for two crossing trains. Three measures of timetable flexibility are proposed and they can be used to evaluate how infrastructure configuration, vehicle properties, punctuality etc affect possibilities to alter the timetable. Double-track lines operated with mixed traffic show properties similar to those of single-tracks. In this case overtakings imply scheduled delays as well as risk of delay propagation. Two different methods are applied for analysis of double-tracks: a combinatorial, mathematical model (TVEM) and simulation experiments. TVEM, Timetable Variant Evaluation Model, is a generic model that systematically generates and evaluates timetable variants. This method is especially useful for mixed traffic operation where the impact of the timetable is considerable. TVEM may also be used for evaluation of different infrastructure designs. Analyses performed in TVEM show that the impact on capacity from the infrastructure increases with speed differences and frequency of service for the passenger trains, whereas the impact of the timetable is strongest when the speed differences are low and/or the frequency of passenger services is low. Simulation experiments were performed to take delays and perturbations into account. A simulation model was set up in the micro simulation tool RailSys and calibrated against real operational data. The calibrated model was used for multi-factor analysis through experiments where infrastructure, timetable and perturbation factors were varied according to an experimental design and evaluated through response surface methods. The additional delay was used as response variable. Timetable factors, such as frequency of high-speed services and freight train speed, turned out to be of great importance for the additional delay, whereas some of the perturbation factors, i.e. entry delays, only showed a minor impact. The infrastructure factor, distance between overtaking stations, showed complex relationships with several interactions, principally with timetable factors. / QC20100622 / Framtida infrastruktur och kvalitet i tågföring

Die Bestrahlung von tetraedrisch amorphen Kohlenstoff (ta-C) mit schnellen schweren Ionen führt zur Bildung von mikroskopischen elektrisch leitfähigen Ionenspuren mit Durchmessern um 10 nm. Dieses Phänomen ist auf das sp² zu sp³ Hybridisierungsverhältnis des amorphen Kohlenstoffes zurückzuführen. Das einschlagende Ion deponiert eine große Menge Energie innerhalb des Spurvolumens, so dass eine Materialtransformation hin zu höheren sp² Hybridisierung stattfindet. Hierdurch wird die elektrische Leitfähigkeit der Ionenspur stark erhöht. Dieser Effekt kann durch die Zugabe von Verunreinigungen wie Kupfer verstärkt werden. Das Ziel dieser Arbeit ist die umfassende Analyse des elektrischen Verhaltens von ta-C mit besonderen Augenmerk auf die Auswirkungen von Kupferverunreinigungen und Ionenspuren. Der Effekt von Kupferverunreinigungen auf das wichtige Hybridisierungsverhältnis vom amorphen Kohlenstoff wird vermessen. Darüber hinaus wurden alle Proben elektrisch mit makroskopischen Kontakten im Temperaturbeireich von 20 K bis 380 K analysiert. Mikroskopisch wurden einzelne leitfähige Ionenspuren mit Hilfe von atomarer Kraftmikroskopie betrachtet. Die statistische Verteilung der Spureigenschaften in Kohlenstofffilmen mit verschiedenen Kupferkonzentrationen werden verglichen, um die Spurbildung besser zu verstehen. Die normalisierten durchschnittlichen Spurleitfähigkeiten aus mikroskopischen und makroskopischen Messungen werden verglichen. Hierbei kann die Zuverlässigkeit der beiden experimentellen Methoden bewertet werden und mögliche Fehlerquellen ausfindig gemacht werden. Schließlich wird ein Konzept für eine Anwendung unterbrochener Ionenspuren gezeigt.

Ces travaux de thèse s'inscrivent dans le cadre d'un vaste projet qui vise à construire des membranes hybrides constituée d'un support solide nanoporeux et de protéines canal-ionique biologiques. Nous nous intéressons ici à un film polymère nanoporeux en polycarbonate et à la Gramicidine-A. La membrane ainsi réalisée est étudiée par des mesures expérimentales. Ce travail peut être divisé en deux parties. Dans la première, nous rapportons l'étude du confinement de la protéine canal ionique, au sein des nanopores du film « track-etched » en polycarbonate. Après imprégnation de gA, la membrane est étudiée par Spectroscopie de Fluorescence Confocale. Les premiers résultats expérimentaux particulièrement encourageants montrent que la gA est localisée dans les nanopores et non pas à la surface de la membrane. Dans la deuxième, les propriétés de transport ionique de la membrane hybride sont caractérisées par le biais de deux grandeurs : d'une part les coefficients de diffusion mesurés à partir d'une cellule et d'autre part les conductivités via la Spectroscopie d'Impédance Complexe (S.I.C). Les électrolytes aqueux étudiées sont : XCl(2) où X=Na, K, Mg et Ca à des concentrations comprises entre 5.10-3 à 1M. Une étude statistique approfondie des données obtenues par la méthode de la variance permet de déterminer les effets relatifs des différentes variables : nature et concentration du sel, présence de la Gramicidine A et traitement à l'éthanol de la membrane. Cette analyse révèle clairement que la présence de Gramicidine A au sein des nanopores de 15nm modifie de façon positive le transport ionique. Il est, par contre, difficile de conclure sur la nature sélective du transport ionique en présence de cette protéine. Ce travail de thèse ouvre un champ de recherche très prometteur dans le domaine de la nanofiltration. / This project of thesis is to build of a bio-inspired hybrid membrane made of a thin nanoporous polymer film in which a biological ionic channel is confined. Thus, this work may be divided in two parts. First, we report the confinement of the biological ionic channel, i.e. Gramicidin A, inside the nanopore of nanoporous thin film, i.e. a track etched polycarbonate film (Whatman NucleoporeTM). After impregnation with Gramicidine-A, the membrane is studied by means of confocal fluorescence spectroscopy. The results show the ionic channel is well located into the nanopores and not at the surface of the membrane. Secondly, ionic transport properties are measured by means of two experiments: on the one hand, ionic diffusion coefficients are measured using a cell and on the other hand, ionic dc conductivity is measured via Complex Impedance Spectroscopy (SIC). Various aqueous electrolytes (XCl(2) where X=Na,K, Mg et Ca) at different concentrations ranging from 5.10-3 à 1M are carried out. A statistical analysis of the data so-obtained allows to determine the relative effects of the different parameters: the nature and concentration of the electrolytes, the presence of Gramicidine A and the membrane pre-treatment with ethanol treatment. It is thus clearly pointed out that the presence of Gramicidine A inside the 15nm nanopores improves ion permeability. However, it is difficult to conclude about ionic selectivity of the hybrid membrane. Nevertheless, this work which is the first attempt ever to build such a bio-inspired system opens an extremely promising field of research in the domain of nanofiltration.

Knä- och höftplastik är bland de vanligaste kirurgiska ingreppen och har en stor positiv inverkan för den enskilda individens livskvalitet. Det har utarbetats flera vårdmodeller för patientkategorin som genomgår en knä- eller höftplastik, dels för att minska vårdkostnader men även för att förbättra vården. Det behövs emellertid mera kunskap om patientens upplevelse eftersom vården är i ständig utveckling. Studiens syfte var att beskriva patientens upplevelse av hemgång från en specialiserad elektiv enhet, den första postoperativa dagen efter knä- eller höftplastik, och första tiden efteråt. Telefonintervjuer utfördes med 12 patienter, och analyserades enligt kvalitativ innehållsanalys, med en induktiv ansats. Resultatet utmynnade i fem huvudkategorier med respektive underkategorier. Huvudkategorierna som framkom var; Den betydelsefulla hemmiljön, Information från sjukhuset, Oundvikligt hjälpbehov, Återhämtningens utmaningar och Hälsofrämjande kontakt. Informanterna delade en positiv upplevelse av hemgång den första postoperativa dagen och kunde hantera eventuella svårigheter på ett adekvat sätt, på egen hand eller med stöd av medskickad dokumentation, anhöriga eller kontakt med sjukhuset. Hemgång dagen efter knä- eller höftplastik upplevs som tryggt. / Knee and hip arthroplasty are among the most common surgeries available today and have a great impact on the quality of life of the individual. Several care models have been developed for patients having had knee or hip arthroplasty, not only to address the cost of healthcare, but also to improve the quality of the care itself. However, more knowledge about a patients experience following surgery is required as the care is continually progressing. The purpose of this study was to document the experience of a patient following a knee or hip arthroplasty. We aim to document their experiences returning home from a specialized elective unit, their first day post operation, as well as the initial period of recovery. Phone call interviews were carried out with 12 patients, and analyzed according to qualitative content analysis with inductive approach. The results were divided into five main categories, each with their own sub-categories. The main categories were; the importance of the home environment, information from the hospital, the necessity of help, challenges of recovery and health promotion contact. The participants reported a positive experience returning home after the first postoperative day and were able to handle potential issues in an adequate manner; on their own, with support from informative documentation, with help from relatives or through contact with the hospital. The experience of returning home the first day post operation, after a knee or hip arthroplasty is considered comfortable.