The study takes place in the capital of Sweden, Stockholm. It focuses on how the past reforms since the 90s have changed the teachers’ occupation as a profession. The study is partially based on analysis of prior research and documents related to the thesis. The cornerstone of it is based on four immerse interviews carried out in three different schools. Two of which were private schools and the third is a municipal school. It is therefore a qualitative study. The result shows that some elements concerning teachers’ profession have been weakened, this in terms of autonomy, less time than before to develop their own educational knowledge and stimulate the pupils’ development. The reason for this depends on the increased governance, administrative work and decreased authority. A possible explanation for this is because of the public school sector to imitate the private sector. Since the pupils’ definition of being just a pupil has altered into becoming a customer has induced them with rights to demand certain requests. This is a downward spiral where teachers’ are compelled to fulfill management directives because society no longer trusts in the teachers’ “silent knowledge”.

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Uppsatsen undersöker om reformen från 2011 om betyg i årskurs 6 påverkade läromedelsförfattarna för matematik i grundskolan. Särskilt studeras reformen påverkade dem att ändra innehållet i lärarhandledningar i matematik så som att lägga till eller utvidga avsnitten om bedömning och bedömningsstöd.   Syftet med uppsatsen är att undersöka förutsättningarna för att implementera läroplanen 2011 och då i synnerhet hur statens direktiv om betyg och bedömning tar sig i uttryck i lärarhandledningar. Uppsatsens urvalsbegränsningar är att materialet ska ha publicerats innan lagen om betyg i årskurs 6 samt innan läroplanen 2011 (10 kap. 15 § SFS 2010: 2022; Skollag, 2010:800). Metoden som används i uppsatsen är en kvantitativ innehållsanalys av förekomsten av bedömningsstöd i lärarhandledningar från perioden Lpo 94, som kombinerats med en fallstudie av vissa utvalda läroboksförfattares bedömningsstöd. Resultatet visade att lärarhandledningarna mellan 1994 till 2011 innehöll bedömningsstöd men i väldigt låg grad. Boken med mest bedömningsstöd var Matematikboken 6 (Undvall, 2007). I slutsatsen kom jag fram till att reformen från 2011 om betygsinförandet i årskurs 6 påverkade läromedelsförfattarna till stor del och att det skedde en ökning när det kom till mängden bedömningsstöd i lärarhandledningar i matematik. Resultaten av analysen visade att om läromedelsförfattarna (transformeringsarenan) inte lyssnar på staten (formuleringsarenan) så kan skolan, klassrummet och lärarna (realiseringsarenan) påverkas. Detta kan i längden leda till att realiseringsarenan inte följer formaliseringsarenans riktlinjer. Betyg, bedömningsstöd, innehållsanalys, läroplansteori, reformer

In methanol processing plants, steam-methane reformers consist of hundreds of vertical tubes operating at temperatures up to 1000°C. These reformer tubes fail by creep through the formation of creep voids during service. Preliminary research showed that the occurrence of these voids was not random and may be related to certain microstructural features of the material. In the present research, the technique of serial sectioning was used to generate threedimensional reconstructions of voids in several steam-methane reformer tube samples with creep damage. The serial sectioning method and subsequent 3D reconstruction revealed creep void information such as size, density, location, and shape in three-dimensions, information that cannot be obtained from two-dimensional micrographs alone. Samples were obtained at various locations along the length of an ex-service reformer tube to investigate the effects of service conditions on the characteristics of creep voids. In addition, samples were taken from various positions along the wall thickness where there were differences in temperature, stress, and microstructure. Additionally, the identity and crystallographic orientations of the phases adjacent to creep voids were studied by electron backscatter diffraction (EBSD) to determine the crystallographic trends in creep void locations. Three dimensional observations revealed that creep voids were indeed not uniformly distributed through the volume in terms of their size, shape, and location. All voids appeared next to carbides and these voids came into contact with M₂₃C₆ precipitates somewhere along their perimeter. Most of the voids were found on austenite (ɣ) grain facets (the interface between two ɣ grains) but the larger voids were generally found at grain edges and corners. The grain boundaries where voids were located were generally oriented at 45 degrees with respect to the hoop stress direction. Here, the effective stress due to a combination of loading and temperature were highest. xviii Abstract EBSD results showed that 80% of the M₂₃C₆ precipitates surrounding these voids have an irrational crystallographic orientation relationship (OR) with the austenite matrix. In contrast, grain boundary precipitates in an aged sample always show a rational OR with respect to one adjacent grain. This implied that the preferred sites for creep voids are low registry boundaries between M₂₃C₆ precipitates and austenite. The data obtained from 3D observations were applied to a classic void growth model. Various permutations of the parameters obtained from this work were applied to the model to simulate conditions that may be beneficial to extending the service lives of reformer tubes. It was shown that the void growth model required accurate and representative materials constants for good estimation of life. Furthermore, the model revealed that more work was required in terms of observations of void nucleation in 3D, in order to fully utilize the model. Finally, it was shown that void density measurements are the most critical item for accurate prediction of growth of voids.

SAMMANFATTNING Anton Forsander & Christoffer Johansson Hur beskriver fritidshemslärare tillkomsten av del fyra som en egen del i läroplanen? Engelsk titel: Perceptions of school-age educare teachers on chapter four in the school-age educare curriculum Antal sidor: 27 Syftet med studien är att undersöka om del fyra i läroplanen, som är tillskriven fritidshemmet, förtydligar fritidshemslärarens yrkesuppdrag samt hur uppfattningarna av yrkesrollen skiljer sig mellan olika fritidshemslärare. Studiens frågeställningar är följande: Hur beskriver fritidshemslärare sitt uppdrag med utgångspunkt i del fyra av läroplanen? Hur beskriver fritidshemslärare implementeringen av del fyra i läroplanen? För att få svar på dessa frågor genomfördes sex stycken intervjuer med fritidshemslärare vid olika skolor inom ett avgränsat geografiskt område. Genom att del fyra tillkommit som en egen del i läroplanen har uppdraget för fritidshemslärare förtydligats och delvis förändrat uppfattningen av densamma. Dock framgår det av resultatet att det fortsatt finns ett stort behov av att förtydliga yrkesuppdraget för andra än fritidshemlärare. Implementeringen av del fyra i läroplanen har till största del upplevts som positivt. Fritidshemslärarna själva har länge kämpat för en egen del i läroplanen och uttrycker sig därför positivt till detta. Dock har det framgått att implementeringsarbetet varierat mellan de olika skolorna som deltagit i studien. Då forskning inom området rörande implementering av läroplaner samt hur det berör fritidshemsverksamheten är detta ett område som fortsatt är i stort behov av vidare forskning, samt att denna forskning efterfrågas.

Syftet med uppsatsen är att undersöka vilka klagomål som medlemmarna i Sveriges folkskollärarinneförbund förde fram mellan 1957 – 1962 och om dessa ändrade karaktär i relation till olika reformer och förändringar på skolområdet under perioden.Åren efter 1945 har kallats för samhällsreformernas tid och förändringen fick återverkningar på folkskolan. Skolutredningar och skolkommissioner påbörjades och utmynnade exempelvis i införandet av en obligatorisk nioårig grundskola. Grundskolereformen påverkade skolväsendet i allmänhet och folkskollärarinnorna i synnerhet.Undersökningen visar inte bara de tre vanligaste klagomålen. Vidare pekar den ut vad folkskollärarinnorna klagade på och dessutom belyses klagomålens ändrade karaktär i ljuset av olika reformer.

Principles of concurrent development are applied to the design of a small-scale device for converting natural gas or liquefied petroleum gas into hydrogen. The small hydrogen generator is intended for serial production for application in the production of industrial hydrogen, fueling stationary fuel cell power systems and refueling hydrogen-fueled fuel cell electric vehicles. The concurrent development process is contrasted with the traditional, linear development process for petrochemical systems and equipment, and the design is benchmarked against existing small hydrogen generators as well as industrial hydrogen production apparatus. A novel system and hardware design are described, and a single cycle of concurrent development is applied in the areas of catalyst development, thermodynamic optimization, and reactor modeling and design. The impact of applying concurrent development techniques is assessed through economic modeling, and directions for future development work are identified. / Ph. D.

Abstract Reformer, the most important link of fuel cell, is the main set to create the hydrogen. After the fuel passes through the catalytic reaction by reformer, will produce hydrogen and chemical substances, the hydrogen will become the energy to support fuel cell. At the present day, the technology of PEM fuel cell and traditional fuel reformer has already existed, only need to reduce the volume, cost and to promote the efficiency. Catalytic layer, with the construction of microchannel, makes the adequate impact to gas and catalyst to promote the efficiency. This research uses the Lattice Boltzmann method (LBM) to simulate the fluid field and heat-mass transfer of microchannel, to discuss the function influence to the different parameter such as velocity, temperature, channel length, and channel height. The result displays, with the same inlet speed and temperature, by the increasing of the channel length, the amount of hydrogen will raise and residual methanol will reduce. When the channel length is more than 500£gm, the produce rate of hydrogen will not be a big change. If fix the channel length at 500£gm, under the different inlet temperature, while the maximum concentration at inlet, the speed of hydrogen at inlet is not the same. The best inlet speed will increase with the higher temperature. When fix the channel length at 500£gm, raising the altitude to 500£gm, the hydrogen product will not increase, on the contrary, it¡¦ll go down. Keywords¡GFuel cell reformer¡BMicorchannel of hat and mass transfer¡BNumerical simulations

A numerical study was carried out to improve the design of an autothermal reformer for the onboard production of hydrogen to be used in fuel-cell- powered auxiliary power units (APU) to provide heating and electricity in long haul trucks when they are at rest. The development of these auxiliary power units is based upon the use of power generated by solid oxide fuel cell (SOFC) system, instead of from a conventional gasoline engine. The present work was undertaken to improve the design of a prototype autothermal fuel reformer that had been developed by the Fuel Cell Research Centre (FCRC) at Queen’s University to convert liquid hydrocarbon truck fuel to a hydrogen rich product gas. In this development work and in the previous work iso-octane (C8H18) has been used as a surrogate fuel. Using this surrogate of gasoline, the reformer was simulated using various inlet steam/carbon (H2O/C), oxygen/carbon (O/C) molar ratios and gas-hourly-space-velocity (GHSV). In the reformer considered the reforming process is carried out in a compact tubular reactor with a centerline thermocouple tube using a 2% Pt-ZrCe based catalyst with a local porosity of 0.6. During the initial simulations, it was observed that near the start of the catalyst region there were large temperature gradients due to an exothermic partial oxidation reaction. In order to reduce the temperature gradients and facilitate heat transfer by conduction along the reformer, the central thermocouple tube was replaced with a central solid rod. The effects of variations in the thermal conductivity of central solid rod, of the reactor wall, of the catalyst bed, of the inert porous material near the inlet and the outlet of the catalyst bed, of the gas hourly space velocity, of the effectiveness factor of the chemical reaction mechanism on the performance of the reactor were studied. The results so obtained were analyzed to determine potential design improvements that would increase the hydrogen output. The results were compared with the previous numerical and experimental results obtained in the previous studies of the reformer and found to be in good agreement with the general trends of the temperature profiles as well as the outlet molar concentrations of product species. After the analysis and evaluation of all the results, it was found that by replacement of central thermocouple tube with central solid rod made of high conductivity material and by using material for inert porous region at the outlet that had a thermal conductivity equal to that of the catalyst bed led to more even temperature profiles within the catalyst region. It was also found that the hydrogen molar percentage output could be increased by approximately more than 25% and that the length of the reactor could be reduced by 20mm by incorporating these changes in the reformer design. / Thesis (Master, Mechanical and Materials Engineering) -- Queen's University, 2009-03-09 12:14:27.627