Osteochondral lesions of the talus (OLTs) are the third most common type of osteochondral lesion and can cause pain and instability of the ankle joint. Episurf Medical AB is a medical technology company that develops individualized implants for patients who are suffering from focal cartilage lesions. Episurf have recently started a project that aims to implement their implantation technique in the treatment of OLTs. This master thesis was a part of Episurf’s talus project and the main goal of the thesis was to find the optimal implantation angle of the Episurf implant when treating OLTs. The optimal implantation angle was defined as the angle that minimized the maximum equivalent (von Mises) strain acting on the implant shaft during the stance phase of a normal gait cycle. It is desirable to minimize the strain acting on the implant shaft, since a reduction of the strain can improve the longevity of the implant. To find the optimal implantation angle a finite element model of an ankle joint treated with the Episurf implant was developed. In the model an implant with a diameter of 12 millimeters was placed in the middle part of the medial side of the talar dome. An optimization algorithm was designed to find the implantation angle, which minimized the maximum equivalent strain acting on the implant shaft. The optimal implantation angle was found to be a sagittal angle of 12.5 degrees and a coronal angle of 0 degrees. Both the magnitude and the direction of the force applied to the ankle joint in the simulated stance phase seemed to influence the maximum equivalent strain acting on the implant shaft. A number of simplifications have been done in the simulation of this project, which might affect the accuracy of the results. Therefore it is recommended that further, more detailed, simulations based on this project are performed in order to improve the result accuracy. / Fokala broskskador på talusbenet är den tredje vanligaste typen av fokala broskskador och kan ge upphov till smärta och instabilitet av fotleden. Episurf Medical AB är ett medicintekniskt företag som utvecklar individanpassade implantat för patienter med fokala broskskador. Episurf har nyligen påbörjat ett projekt där deras teknik ska användas i behandlingen av fokala broskskador på talusbenet. Den här masteruppsatsen var en del i Episurfs talusprojekt och dess huvudmål var att finna den optimala implantationsvinkeln av Episurfs implantat i behandlingen av fokala broskskador på talusbenet. Den optimala implanteringsvinkeln definierades som den vinkel som minimerade den effektiva von Mises-töjningen som verkade på implantatskaftet under stance-fasen i en normal gångcykel. Det är eftersträvansvärt att minimera belastningen på implantatskaftet eftersom en reducering av belastningen kan förbättra implantatets livslängd. En finita element-modell av en fotled behandlad med Episurfs implantat utvecklades för att för att finna den optimala implantationsvinkeln. I modellen placerades ett implantat med en diameter på 12 millimeter på mittendelen av talus mediala sida. En optimeringsalgoritm utformades för att finna implantationsvinkeln som minimerade den effektiva von Mises-töjningen på implantatskaftet. Den funna optimala implantationsvinkeln bestod av en vinkel på 12.5 grader i sagittalplan och en vinkel på 0 grader i koronalplan. Både storleken och riktningen på kraften som applicerats på fotleden under den simulerade stance-fasen av gångcykeln verkade påverka belastningen på implantatskaftet. Ett antal förenklingar har gjorts i projektets simuleringar, vilket kan påverka noggrannheten i resultatet. Därför rekommenderas att ytterligare, mer detaljerade simuleringar baserade på det här projektet görs för att förbättra resultatets noggrannhet.

Functionally graded materials (FGMs) are advanced materials and their main characteristic is microstructure and composition variation over the volume of the specimen. This variation of the composition results in changing of material properties in the component. In FGMs usually there are two different types of powder materials such as metal and ceramic powders which are mixed to build up the graded region. These grade layers are placed between the metal and ceramic layers and by this approach a smooth and gradual transient from metal to ceramic can be achieved.Sintering is the main technique to manufacture these types of materials. During the sintering process, cooling of the specimen from sintering temperature to room temperature results in generation of thermal residual stresses within the material. These thermal stresses may cause crack propagation and failure of the material.Distribution analysis of these thermally induced stresses within the material has been carried out in this thesis work. Finite element package ABAQUS has been used in order to simulate the distribution of the thermal residual stresses in the materials. In order to achieve the optimal design for different geometries the parametric study also has been performed. For example influence of number of layers, mixing ratio and porosity has been investigated.Based on the finite element results for cylindrical and cuboid models, non-linear composition variation for both geometries has no improving effect in terms of induced thermal residual stresses. Porous material shows less thermal stress than non-porous material. As the amount of porosity for individual layer was considered in simulation process, this approach resulted in decreasing of thermal stresses within the material. Moreover, non-uniform thickness of graded layers was not beneficial for stress reduction. This variation of thickness results in increasing of thermal residual stresses within the material.

The correlatioin between residual stresses and the global properties from an indentation test, i.e. hardness and size of the contact area, has been studied frequently in recent years. The investigations presented have been based on experimental, theoretical and numerical methods and as a result, the basic features of the problem are fairly well understood in the case of residual equi-biaxial surface stresses. The more general case, when the principal surface stresses are not necessarily equi-biaxial, has received nuch less attention and it is therefore the aim of the present study to remedy this shortcoming. In doing so, qualitative results are of immediate interest in this initial study but possible ways of quantitative descriptions are also discussed for future purposes. The present analysis is based on numerical methods and in particular the finite element method (FEM) is relied upon. Classical Mises elastoplastic material behavior is assumed throughout the investigation.

Rapid constructed embankments founded on soft deposits have a negative influence on the short term stability. Many engineering constructions such as road and railway embankments are often constructed on soft clay deposits. In stability analysis calculation of safety factor (SF), as the primary design criteria can be evaluated through different numerous methods such as limit equilibrium method (LEM) and finite element method (FEM). It is of particular interest to determine/estimate appropriate stability of the specified embankment which is highly dependent on the analysis method used. Therefore, it is a challenge for geotechnical engineers to judge which analysis method can simulate better the reality.  The aim of this thesis is to increase understanding applicability of the three applied programs; Plaxis2D, Plaxis3D and Slope/W in simulating and stability analysis/estimation of embankments founded on clay deposits.  The work has involved analysis and comparison of the stability through estimate of the SF and the critical failure surfaces obtained through 2D and 3D programs. Four case configurations were studied for the stability analysis. In each case variation in plastic parameters of clay (φ-c) or load geometry, was the scenario to make the comparison analysis. Moreover, application FEM3D offers an attractive alternative to traditional approaches to the problem (especially for LEM).  The main conclusions from this study are the following:  (1)   Concerning the three applied programs, FEM3D has the minimum SF sensitivity to change in plastic parameters of clay deposit. (2)   For embankments founded on clay deposit, the 3D failure surfaces are easily found via the FEM3D analysis program, which is closer to reality, while failure results of 2D analysis programs can never occur in reality. (3)   Using 2D analysis method instead of 3D, to investigate the stability of 3D embankment model tend to give higher SF results up to 14% for embankments  founded on undrained clay deposit. (4)   The failure surfaces in 3D analysis are likely to be shallower than in the corresponding 2D model. (5)   Results from the 3D analysis through hand calculation and program calculation do not correspond with each other for embankment founded on soft clay deposit. The first reason is rooted in limitation of the hand formula. The formula is suitable for embankment founded on one layer deposit (soil); however an embankment founded on 3 layers of deposit (soil) was analyzed in this study. The second reason is related to applied method of calculation. 3D hand calculation formula is based on method of slices however; analysis method in program calculation is based on FEM.

<p>Embryonic development is a complicated phenomenon influenced by genetic regulation and biomechanical cellular behaviors. However, the relative influence of these factors on spatiotemporal morphogen distributions is not well understood. Bone Morphogenetic Proteins (BMPs) are the primary morphogen guiding the dorsal-ventral (DV) patterning of the early zebrafish embryo, and BMP signaling is regulated by a network of extracellular and intracellular factors that impact the range and signaling of BMP ligands.  Recent advances in understanding the mechanism of pattern formation support a source-sink mechanism, however, it is not clear how the source-sink mechanism shapes patterns in 3D, nor how sensitive the pattern is to biophysical rates and boundary conditions along both the anteroposterior (AP) and DV axes of the embryo.</p><p> Throughout blastulation and gastrulation, major cell movement, known as epiboly, happens along with the BMP mediated DV patterning. The layer of epithelial cells begins to thin as it spreads toward the vegetal pole of the embryo until it has completely engulfed the yolk cell. This dynamic domain may influence the distributions of BMP network members. This project aims to investigate the multiscale regulatory network of the BMP signaling dynamics along with the biophysical deformation of the embryo tissue during epiboly. </p><p> In this study, we present a three-dimensional (3D) growing domain mathematical modeling framework to simulate the BMP patterning and epiboly process during the blastula to gastrula stage zebrafish embryo, with both finite difference and finite element approaching. These models provide a starting point to elucidate how different mechanisms and components work together in 3D to create and maintain the BMP gradient in the zebrafish embryo. We are interested in how the cellular movements impact the formation of gradients by contributing an advective term whereby the morphogens are swept with the moving cells as they move vegetally. Dynamic cell imaging data are used to quantify the cell movement during the epiboly. We evaluated the accuracy of the mesh updating compared to the advection caused by cell movement and its role in embryonic patterning. Quantitative whole-mount RNA scope data of BMP2b, Chordin, Noggin, Sizzled, and phosphorylated-SMAD data are collected and analyzed precisely to test the hypotheses of the gradient formation mechanism in our model. We also present a novel approach of Neuro Network model to accelerate the computationally intensive PDE simulations. Our goal is to develop a complete advection-diffusion-reaction model that incorporates all stages of zebrafish embryonic development data. By combining the biophysics of epiboly with the regulatory dynamics of the BMP network, we can test complex models to investigate the consistent spatiotemporal DV patterning in the early zebrafish embryo.</p>

Cross Laminated Timber (CLT) has in recent years become a more important building material. This means that the demand for accurate calculation methods in building standards such as Eurocode 5 has increased. There is limited knowledge about the connections in CLT buildings which is an important part of a CLT structure. This thesis was therefore focused on investigating a wall-floor-wall type connection commonly found in platform type buildings.  An experimental and numerical study on typical wall-floor-wall connections was carried out in this thesis. In the experimental part 60 tests with 8 different configurations were conducted to investigate the influence of different parameters on the connection, moment capacity and rotational stiffness. During the tests the deformation of the specimens under four load levels were investigated. Compression tests were also performed on the specimens to determine the compressive strength and stiffness of the elements. In the numerical part two different models for the connection were created. One simplified model with rotational springs and one more complex model with compression springs. With these models the influence from the number of stories, span and thickness of the wall on the global behavior of a structure was investigated.  The result from this thesis shows that there is both moment capacity and rotational stiffness in the wall-floor-wall type connection that can be utilized in the design phase of a structure. This was proven by both the experimental and the numerical study. The parameters that influence the behavior of the connection most were the load level applied on the wall and the wall thickness. The model created in the numerical study showed great potential regarding the replication of the connection behavior observed in the experimental study.

Syftet med detta examensarbete var att förbättra kundupplevelsen med avseende på en viss typ av konsument. Dagens matbutiker har hyllplan som är högt placerade och för en del konsumenter är detta ett problem. De konsumenter som upplever höga hyllplan som ett problem är bland annat funktionsnedsatta och personer med en kortare längd än genomsnittet. I många matbutiker är avståndet mellan det högsta hyllplanet och taket stort och då är inte ytan utnyttjad maximalt. Resultatet är tänkt att ge ett förslag på hur dessa två problemen kan lösas. En strukturerad produktutvecklingsmetod har applicerats genom hela processen av examensarbetet för att ta fram en lösning på hur varubutikerna kan optimeras till att det blir mer lättillgängligt för alla typer av konsumenter. Planeringen av detta utfördes med hjälp av ett Gantt-schema. Konceptet som framtogs i rapporten optimerades genom att komplettera med en till komponent. Konceptet har som syfte att kunna förlängas för att kunnata ner produkter med en max vikt på 0,5 kg från den högsta hyllplanet.Avgränsningarna för arbetet har tagit hänsyn till de hyllor som finns igångarna i dem större matbutikerna samt att arbetet har en begränsad tidsram och hur prototypens framtagning kommer att ske.

Purpose: This work investigates the load-bearing capacity of a foundation built out of cross-laminated timber. The foundation is built with the same principles as a slab on grade made out of concrete. The purpose is also to account for the different operating principles of a wooden slab on grade with, and without, an edge beam. Method: To answer the issues at hand, a literature study was used to collect relevant information. Calculations were made with data from an example house which is presented with various drawings that illustrate the building’s size and form. Data from the example house is used to determine the loads. Thereafter, calculations were made both by hand and with the computer software FEM-design which uses the finite element method. Results: The main principle of shallow foundation design is contact pressure. The calculations show a range of contact pressure applied to the underlying soil and insulation of the foundation. Load combinations according to Eurocode 1 are used to determine the sum of loads affecting the foundation. All load combinations result in a higher contact pressure when using a foundation without an edge beam. Calculations done by hand presents the maximum value of contact pressure of the two separate foundations and highlights the difference between the two. The results from hand calculations and computer software regarding contact pressure varies. Calculations performed in FEM-design use three variations of the modulus of subgrade reaction to investigate the impact of said modulus. FEM-design also calculates the deflection which is significantly larger without an edge beam. The Conclusions of this work include a reduction in contact pressure when the wooden foundation is constructed with an edge beam. Calculations done by hand may overestimate the stiffening ability of the wooden edge beam. The modulus of subgrade reaction affects the magnitude of deflection in a larger extent than the contact pressure. It is suitable to design a wooden foundation with an edge beam with the purpose of keeping deflection to a minimum.

Sammanfattning: Studiens syfte var att undersöka möjligheter och hinder kring lärares och elevassistenters samver- kan inom gymnasiesärskolan och hur dessa faktorer påverkar elevernas skolvardag. Studien har ett interaktionsperspektiv. Elevassistenter och lärare är två yrkesroller som påverkas av faktorer på både individ- och organisationsnivå. Det övergripande ansvaret har rektor, därför valdes även att inkludera rektorns perspektiv i undersökningen. Senges teori (2006) om samverkan för organi- sationsutveckling har utgjort utgångspunkt för uppläggning och genomförande av studien. Som metod valdes semistrukturerade, kvalitativa intervjuer. Studien riktade sig till tre yrkeskategorier: elevassistenter, lärare och rektorer. Detta för att spegla upplevelser och perspektiv från olika håll/ nivåer inom organisationerna. Resultatet avtäcker en mångfacetterad bild av sanningar utifrån respektive yrkesroll och organisation. Undersökningens slutsats gav bilden av en komplex yrkes- vardag där framgångs- och motgångsfaktorer är ständigt närvarande och hanteras kontinuerligt i yrkesrollernas dagliga strävan för samverkan med elevens bästa i fokus.

Detta examensarbete syftar till att med digitala kvalitativa intervjuer undersöka lärares användning av den kooperativa och traditionella undervisningsmetoden i matematikklassrummet i årskurs F-3. Studiens syfte är även att ta reda på vilken av de två metoderna lärare anser är den mest effektiva för att främja alla elevers kunskapsutveckling. Studien utgår från de fem grundprinciperna för kooperativt lärande; positivt ömsesidigt beroende, lika delaktighet och samtidig stödjande interaktion, eget ansvar, samarbetsfärdigheter och ‘feedback, feedup och feedforward’ (3F). Resultatet visar på att lärarna applicerar en blandning av de olika metoderna. Detta beror på att läraren kan behöva individanpassa beroende på vad som gynnar den enskilda eleven. Resultatet visar även på att de olika metoderna används i olika stor grad beroende på vilket arbetsområde lektionen behandlar. Den kooperativa undervisningsmetoden anses vara den mest effektiva för att främja elevernas kunskapsutveckling men eftersom den inte passar alla elever behövs en blandning av de båda för att tillgodose alla elevers olika behov.