Under två terminer har vi medverkat i en forskningscirkel på en grundskola som behandlat historieundervisning i en mångkulturell miljö. Forskningscirkeln startades i samband med att den aktuella skolan fick ett stort tillskott av elever med invandrarbakgrund. Det ena syftet med detta examensarbete är att synliggöra lärarnas syn på rollfördelningen inom den aktuella forskningscirkeln. Den rollfördelning vi syftar på är framförallt den mellan forskarna och lärarna, inte lärarna emellan. Det andra syftet är att se hur lärarna upplever att de påverkats av att medverka i forskningscirkeln, och då med fokus på historieundervisning i en mångkulturell miljö. Forskningscirklar inom skolans värld är ett ganska nytt fenomen. I forskningscirkeln möts teoretiker och praktiker kring ett gemensamt problem, utformat av praktikerna. Om forskningscirkeln i skolan ska kunna bli ett möte på lika villkor bör forskarna håller en medvetet låg profil. Risken finns annars att traditionella mönster upprepas; forskarna agerar ledare och lärarna blir de passiva deltagarna som utför uppgifter de tilldelats. Även om forskarnas låga profil kan innebära att arbetsprocessen i cirkeln tar längre tid så uppnås troligtvis resultat som är mer relevanta både för forskare och för lärare. Lärarna i den aktuella forskningscirkeln upplever att forskarna i cirkeln har hållit en låg profil. Deras uppfattning är att alla deltagit på lika villkor, oavsett yrke och tidigare erfarenheter. Dagens forskning inom det historiedidaktiska området fokuserar framförallt på hur man i skolan kan förändra sin historieundervisning utifrån de elever läraren har framför sig, och vems historia det egentligen är som ska förmedlas. Undersökningen visar att lärarna anser att på grund av sin medverkan i forskningscirkeln har det vuxit fram idéer och tankar kring hur de ska kunna förändra sin undervisning. Även om det inte är helt oproblematiskt, så försöker lärarna att hitta nya vägar, så att historieundervisningen ska angå alla i klassrummet. Centrala begrepp för forskningscirkeln och för detta examensarbete har varit, identitet, historiemedvetenhet, kultur och kulturarv. Begreppen har diskuterats utifrån ett didaktiskt perspektiv. / During these two last terms we took part in a research group on history teaching in a multi-cultural environment at a compulsory school. The research group started when the school in question had recently taken on a large number of pupils of a foreign background. This thesis has two purposes, the first of which is to show the teachers’ view on the division of rolls within the aforementioned research group. The division referred to is principally that between the researchers and the teachers, not that between the teachers. The other purpose is to see how the teachers perceived the influence of participating in the research group, the focus being on history teaching in a multi-cultural environment. Research groups in the school world are quite new phenomena. In the research group theoreticians and practitioners meet about a mutual problem, defined by the practitioners. In order for the research group to meet on an equal footing, the researchers have to maintain a consciously low profile. Otherwise they run the risk of repeating a worn pattern where the researchers act as leaders and the teachers become the participants performing their allocated tasks. Even though the researchers’ low profile may mean the work process taking a longer time, chances are that results more relevant to the teachers and researchers are achieved. The teachers in this particular research group feel the researchers in the group did keep a low profile. Their impression is that everyone who participated took part on equal conditions, regardless of their profession and earlier experiences. Research today within the area of history didactics mainly focuses on how schools might change their history teaching based on the pupils sitting in front of the teacher, and on whose history one is actually trying to convey. This research shows that the teachers feel their participation in the research group did provoke ideas and thoughts on how to change the lessons. While it is not completely unproblematic, the teachers are trying to find new ways of making the history lessons relate to everyone in the classroom. Central conceptions for the research group and for this thesis have been identity, history awareness, culture and culture heritance. These conceptions have been discussed from a didactic perspective.

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Dissertation Abstract Abdominalaortic aneurysm (AAA) is a serious disease. Its prevalence is in the developed countries about 3%. As an aneurysm is considered a dilatation of all layers of a vessel wall over 3 cm. Majority of AAA are small and asymptomatic, and although the risk of rupture increases with the size of aneurysm sack, even the small aneurysms rupture. The rupture mortaliry ranges about 70 %. Surgical treatment is indicated in the asymptomatic patients in diameter of AAA over 5 cm. The average speed of growth of AAA is 0.3 cm per year, e.g. in the early diagnosed patients there is a several years interval for a pharmacolocical influencing of the progression of this disease. Knowledge of pathogenesis is essential for any targeted pharmacological treatment. Our prospective, non-randomised studies are based on the application of the stereological methods for the histopathological assessment of the AAA samples. The acquired data enable the statistical analysis, including the null hypothesis testing. In our study analyzing the histopathology of AAA aortae of 65 patients (65 walls and 55 thrombi) and 6 normal abdominal aortae from the organ donors we assessed the following parameters: the area fractions of collagen and elastin, and the length density of elastin in intima and media, the area...

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<p>Firstly, select a nozzle and get all its parameters like spray angle, mass flow rate, dipersion angle and nozzle diameter. Create a domain in which 2 nozzles can fit, as shown in thesis. Divide the domain in 2 zones and perform fine mesh on the top surface of solid surface where spray will heat. Write a function for slab temperature variation and give it as the solid part input. Use DPM model, to create injectors inside the domain and solve.</p>

Att gjuta med betong under vatten är utmanande, och det ställs höga krav på både betongen och utförandet för att resultatet ska bli bra. Peab Anläggning har uppmärksammat en del problem med denna typ av gjutningar och ville därför tydliggöra problematiken för att öka chansen för bra resultat vid framtida undervattensgjutningar. Problemen bestod dels av gjutskador på den färdiga betongkonstruktionen, och dels av problem med betongen under gjutningens gång i form av skum och separation. Examensarbetet sammanställer svårigheterna med undervattensgjutning med självkompakterande betong (SKB) och undersöker vilka faktorer som påverkar det färdiga gjutresultatet. Detta har gjorts genom en litteraturstudie, intervjuer med kunniga personer inom ämnet samt besök på arbetsplatser där undervattensgjutningar utförts. De svårigheter som identifierats delas in under fyra huvudrubriker; planering inför gjutning, betong, form samt utförande. Planeringen inför gjutningen är mycket viktig men svår då många faktorer måste tas hänsyn till, såsom väder och trafik. För att minimera risken för oönskade gjutuppehåll krävs det även en förberedande plan med lösningar på problem som kan uppstå under gjutdagen. Svårigheten med färsk betong är att det är ett levande och därmed oförutsägbart material. Det är nödvändigt att betongen har god sammanhållning så att betongens cementpasta inte vaskas ut i vattnet. Det är även viktigt att betongen har rätt konsistens för att kunna omsluta all armering och fylla ut hela formen. Betongen testas när den kommer till arbetsplatsen. Bland annat kontrolleras betongens lufthalt samt homogenitet och flytbarhet, det senare med hjälp av flytsättmått. Det är viktigt att ta hänsyn till dessa kontroller och att ta beslutet att inte gjuta med dålig betong. Det ställs även höga krav på formen vid undervattensgjutningar. Den måste vara helt tät och byggas på rätt sätt så att skum och bottenslam kan rinna ut ur formen. En svårighet är att dykarna behöver utföra en del av formbyggandet under vattenytan. Utförandet är en stor utmaning, då arbetsmomentet är komplicerat och man gjuter i blindo. Metoden går ut på att betong pumpas ner under vattenytan genom ett betongrör med en undervattensventil. Under gjutningens gång är det viktigt att rörets mynning hela tiden är under betongytan och att gjutröret hålls vertikalt. Slutligen är det värt att nämna att litteraturen som finns idag om undervattensgjutningar är bristfällig, något som gör det svårt att lära sig om ämnet. De förslag på lösningar som grundas på slutsatsen är att all betong som kommer till arbetsplatsen bör testas, trots att det inte alltid är ett krav. Detta så att ett beslut kan tas kring varje enskilt betonglass om betongen är godkänd att gjuta med. För att öka chansen att betongen har önskade egenskaper är det viktigt att betongbilen som levererar betongen till arbetsplatsen är ren och inte innehåller rester av annan betong. Det krävs under hela arbetet en god kommunikation mellan både pumpmaskinist, dykare och arbetsledning för att de gemensamt ska kunna lösa eventuella problem som uppstår. Slutligen rekommenderas att ta hjälp av varandra och dra nytta av den kompetens och erfarenhet som finns inom företaget. / Casting with concrete under water is challenging, and requires high standards on both the concrete and the work practice to achieve good results. Peab noticed problems with this type of casting, and wanted to clarify the difficulties to increase the chance of good results with future underwater castings. The problems were injuries on the finished concrete structure and troubles with the concrete during casting such as foam and separation in the concrete. This paper compiles the difficulties with underwater casting with self-consolidating concrete (SCC) and investigates the factors that affect the final result. This has been done through interviews with experienced people, a literature review and visits to construction site that performed underwater casting. This paper identifies four main issues; pre-casting planning, concrete quality, form and work procedure. The planning is very important but difficult, as many factors need to be considered, such as weather, land traffic and boat traffic. In order to minimize the risk of unwanted breaks during casting, it is good to have a preparatory plan with solutions to problems that may occur. The difficulty with concrete is that it's a living, and thus unpredictable, material. It is very important that the concrete has good cohesion so that the concrete's cement paste is not washed out in the water. It is also necessary that the concrete has good consistency to ensure it will enclose all reinforcement and fill in the entire form. The concrete is tested when it arrives to the construction site. Among other things, the air content as well as homogeneity and flowability are controlled, the latter controlled by a slump flow test. It is important to take these controls into consideration, and to make the decision not to cast with bad concrete. The requirements on the form used during underwater casting are high. It must be completely dense and properly constructed so that foam and sludge can flow out of the form. One difficulty is that the divers sometimes need to build parts of the form under the water. The work practice is challenging as it's complicated and done blindly. The used method is to pump concrete under the water surface through a concrete pipe with an underwater valve. During the casting process, the mouth of the pipe must always be below the concrete surface and the casting tube should be kept vertically. Finally, it is worth mentioning that the literature available today about underwater casting is inadequate, which makes it difficult to learn about the subject. The suggested solutions presented in the report are that all concrete coming to the construction site should be tested, even though it is not always a requirement. Thus, the decision of whether the concrete had a high enough quality for casting would be made for each delivery. In order to increase the chances of the concrete having desired properties, it is important that the truck delivering concrete to the construction site is clean and does not contain residues of a different concrete. Throughout the work, a good communication between pump operator, diver and management is needed to jointly solve problems. At last, it is recommended to help each other and take advantage of the expertise and experience within the company.

Recently ABB AB/Metallurgy has developed a novel temperature measuring system in the mold copper plate for continuous casting, named OptiMold Monitor, with the purpose of dynamically monitoring mold conditions and to control the FC Mold.The OptiMold Monitor temperature signals can be further analyzed for the information of the shape of the meniscus of the molten steel together with fluid flow symmetry and speed. Also, it can be analyzed for extracting information about how the steel has started to solidify in the mold and to detect solidification deficiencies such as cracks or risks of shell break-outs. Algorithms and Matlab codes developed by ABB for the thermal data analysis has perceived good insight into the results. The OptiMold Monitor system is currently being tested in Tata Steel IJmuiden steelworks.Algorithms for local cold and hot spot detection have been suggested for robust performance and to address the issue of false alarms. And the nail bed tests for meniscus profile and speed have been analyzed. / ABB AB / Metallurgi har utvecklat ett nytt temperaturmätningssystem i gjutkopparplattan för kontinuerlig gjutning, benämnd OptiMold Monitor, med syfte att dynamiskt övervaka aktuell gjutningsstatus och för att styra FC Mold.Temperatursignalerna från OptiMold Monitor- kan analyseras vidare för ge informationen om formen av det smälta stålet tillsammans med fluidflödessymmetri och hastighet. Det kan också analyseras för att extrahera information om hur stålet har börjat stelna i formen och för att upptäcka stelningsdefekter som sprickor eller risker för utbrytning av skal. Algoritmer och Matlab-koder som utvecklats av ABB för termisk dataanalys har givit god inblick i resultaten. OptiMold Monitor-systemet testas för närvarande i stålverket Tata Steel IJmuiden. Algoritmer för lokal kylning och detektering av ”hot spots” har föreslagits för att ge robusta prestanda och att för att hantera risken för falska larm. Även resultat från nagelbäddstesterna för gjutprofil och hastighet har analyserats.

Continuous caster moulds are the last and most important stage in the steelmaking process, where inclusions can either be generated or removed. With increasing casting speed using conventional immersion nozzles critical problems, such as unstable bulk mould flow have been noticed. Mould flux entrapment due to vortex and shearing action from the oscillating surface waves have become of particular concern. It is therefore necessary to have a calm inlet flow at the entrance of the mould. Recently, it has been acknowledged that a swirl blade placed at the upstream of the immersion nozzle effectively resolves the problems arising from unstable bulk mould flow. Therefore, to increase the knowledge of effect of swirling flow on the flow pattern in the mould, fundamental mathematical models of a billet mould equipped with a swirl blade in the nozzle have been developed. The model was used to study the effect of divergent angle of the immersion nozzle and mould aspect ratio on the flow field and temperature distribution inside billets moulds. Data from water model experiments were used to verify the mathematical model predictions. A fairly good agreement was found between physical modeling data and predictions, which ensured that the numerical model is reliable. Thereafter, the differences between square and round billet moulds were studied. Next, the effect of changing aspect ratio of the rectangular mould on the fluid flow and heat transfer, while keeping mould surface area constant, was studied. Two types of immersion nozzles, bottomless and conventional, were also analyzed during the research. The model moulds were changed gradually from a square billet with an aspect ratio of 1x1 to a rectangular billet with an aspect ratio of 3x1. First, the temperature and velocity distributions were calculated. Later, unsteady calculations were done to determine velocity fluctuations on the meniscus level for two types of nozzles and several moulds geometries. / <p>QC 20101110</p>

When laying up dry composite materials and aligning the fibers in the appropriate directions it can be a challenge due to the dryness of the fiber and mold design. Several commercial products are available to help fix plies to molds keeping the proper fiber orientation depending upon mold geometry. Prepreg and wet layups do not have this problem due to the inherent inclusion of a matrix in their manufacturing, dry materials have no added epoxy at the time of layup and are therefore in need of assistance maintain position. The purpose of this research is to determine if Super 77™ or EPON™ 2002 increases or decreases mechanical properties of the neat resin and composite laminates; if the increase or decrease is dependent upon the type of epoxy, and if the amount of applied tackifier can be optimized towards a high or low application quantity to minimize any detrimental effects to mechanical properties. Each tackification agent was applied in high and low concentrations to eight composite panels, with two control panels. The EPON™ was applied manually and set with heat exposure while the Super 77™ was sprayed from an aerosol can. The Super 77™ plies were stacked and pressed by hand while the EPON™ plies were stacked and ironed together to create panels, which were then infused with one of two room temperature infusion epoxies, MVS 610 or INF 114. The panels were then cut to specimen size for testing. Neat resin specimens were cast in silicone molds with high and low concentrations of tackifiers and allowed to cure for 12 hours at room temp, then heated to 60° C for 8 Both Super 77™ and EPON™ 2002 reduced the SBS for both epoxies, but Super 77™ reduced the short beam shear more than EPON™ 2002. The modulus of the neat resin cast specimens with high concentration were between 0 to 20% lower than neat resin with no tackifier; the tensile strength was increased for those specimens with Super 77™ and lower for those with EPON™ 2002. Similarly, the Charpy test resulted in higher values for Super 77™ than for EPON™ 2002. The effects of Super 77™ and EPON™ 2002 are complex and varied depending on application concentration, resin, and tackifier type; but the addition of any tackifier reduces mechanical properties from non-tackified laminates.

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