In this thesis, we have used a phase field model for studying the effect of atomic mobility inside the precipitate phase on coarsening behaviour in two dimensional (2D) systems. In all the available coarsening theories, the diffusivity inside the precipitate phase is not explicitly taken into account; this would imply that there is no chemical potential gradient inside the precipitate. This assumption is valid if (a) the atomic mobility inside the precipitate is much higher than that in the matrix, or (b) the precipitate volume fraction is small (i.e. the interparticle spacing is far higher than the average particle size). We undertook this study to evaluate the potential effect of diffusivity in the precipitate on coarsening in situations where conditions (a) and (b), above, do not hold, by studying systems with moderate volume fractions (20% and 30%) and with low atomic mobilities in the precipitate. In our study, we have fixed the atomic mobility in the matrix at a constant value. We have used the well known Cahn-Hilliard model in which the microstructure is described in terms of a composition field variable. The evolution of microstructure is studied by numerically solving a non-classical diffusion equation known as the Cahn-Hilliard equation. We have used a semi-implicit Fourier spectral technique for solving the CH equation using periodic boundary conditions. The coarsening behaviour is tracked and analyzed using number density of particles, their average size and their size distribution. The main conclusion from this study is that, contrary to expectations, the atomic mobility in the precipitate phase has only a small effect on coarsening behavior. Specifically, with decreasing atomic mobility in the precipitate phase, we report a small increase in the number density, a slightly wider size distribution and a slightly smaller coarsening rate. We also add that these effects are too small to allow experimental verification. These results indicate that the need for chemical potential equilibration within each precipitate is not an important factor during coarsening.

This master's thesis deals with modelling and simulation of physical phenomena by cellular automata. The basic methods which model physical phenomena is enumerated and descibed in this thesis. One of the important part of this thesis is a set of demonstration models. Each model is focused on one selected area of physical phenomena. All models are described by transtition rules and the procedure of derivation of these rules is also presented here. There rules were used in implemented models.  Another part of this thesis contains of a simulation application for these models. The real application had been implemented in accord with this design and it has been used to perform the simulation experiments with exemplary models. Results of the simulation experiments are discussed in conclusion of this thesis. One exemplary model had also been adapted for parallel processing. The performances on a computer with different count of working processors were measured and are also discussed in the conclusion of this thesis

Syftet med studien är att bidra med kunskap om hur elever i årskurs 1–3 förståroch förklarar det fysikaliska fenomenet flyta och sjunka. Studien ämnar ävenatt utforska hur en praktisk aktivitet kan bidra till att synliggöra och skapa endjupare förståelse för begreppen Arkimedes princip och densitet för elever pålågstadiet. För att besvara studiens syfte valdes en designbaserad forskningsansats där en aktivitet designades och utfördes med 31 elever i årskurserna 1–3. Aktiviteten spelades in på video- och röstfiler som senare analyserades tematiskt.Resultaten visar att eleverna har viss kunskap om varför vissa saker flyter ochandra sjunker. Resultaten visar även att den praktiska aktiviteten bidrar till attsynliggöra begreppen Arkimedes princip och densitet på ett tydligt sätt vilketvisar att även de yngsta eleverna kan närma sig fysikens begrepp och teorier.När lärare i de lägre årskurserna låter eleverna tidigt börja närma sig och arbetamed naturvetenskapliga begrepp så läggs en bra grund inför kommande studieri de naturvetenskapliga ämnena. / The purpose of this study is to contribute with knowledge about how pupils ingrades 1-3, understands and explain the physical phenomenon of floating andsinking. The study also aims to explore how a practical activity can help tomake the physical phenomenon visible and create a deeper understanding ofthe concepts of Archimedes' principle and density for pupils in primary school.To answer the purpose of the study, a design-based research approach waschosen where an activity was created and performed with 31 pupils in grades1-3 in Sweden. The activity was recorded on video and voice files which werelater analyzed thematically.The results show that the pupils have some knowledge of why some thingsfloat and others sink. The results also show that the practical activity contributes to making the concepts of Archimedes' principle and density visible in aclearer way, which shows that even the youngest pupils can approach physicalconcepts and theories. When teachers in the lower grades allow pupils to startapproaching and working with scientific concepts at an early stage, a goodfoundation is laid for future studies in the natural science subjects.

This thesis takes place in the field of Ambient Intelligence (AmI). AmI Systems are interactive systems composed of many heterogeneous components. From a hardware perspective these components can be divided into two main classes: sensors, using which the system observes its surroundings, and actuators, through which the system acts upon its surroundings in order to execute specific tasks.From a functional point of view, the goal of AmI Systems is to activate some actuators, based on data provided by some sensors. However, sensors and actuators may suffer failures. Our motivation in this thesis is to equip ambient systems with self fault detection capabilities. One of the particularities of AmI systems is that instances of physical resources (mainly sensors and actuators) are not necessarily known at design time; instead they are dynamically discovered at run-time. In consequence, one could not apply classical control theory to pre-determine closed control loops using the available sensors. We propose an approach in which the fault detection and diagnosis in AmI systems is dynamically done at run-time, while decoupling actuators and sensors at design time. We introduce a Fault Detection and Diagnosis framework modeling the generic characteristics of actuators and sensors, and the physical effects that are expected on the physical environment when a given action is performed by the system's actuators. These effects are then used at run-time to link actuators (that produce them) with the corresponding sensors (that detect them). Most importantly the mathematical model describing each effect allows the calculation of the expected readings of sensors. Comparing the predicted values with the actual values provided by sensors allows us to achieve fault-detection.

Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2014-12-22T12:20:23Z No. of bitstreams: 1 Dissertação - Gilmar José do Nascimento - 2014.pdf: 3342644 bytes, checksum: 6d59b125cab769363607e1d9dfce31f4 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2015-01-26T13:24:20Z (GMT) No. of bitstreams: 1 Dissertação - Gilmar José do Nascimento - 2014.pdf: 3342644 bytes, checksum: 6d59b125cab769363607e1d9dfce31f4 (MD5) / Made available in DSpace on 2015-01-26T13:24:20Z (GMT). No. of bitstreams: 1 Dissertação - Gilmar José do Nascimento - 2014.pdf: 3342644 bytes, checksum: 6d59b125cab769363607e1d9dfce31f4 (MD5) Previous issue date: 2014-02-03 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / This work aims to enable the understanding of physics conceptions utilizing basic foundations of mathematics. In this regard, the aim is to highlight both those the phenomena that occur in nature as the phenomena which occur in laboratory manipulations. A extensive research is made about mathematical concepts that will subsequently be applied to several types of problems, being possible understand fundamental aspects involving physical quantities. With the goal to experience the in practice applications, robotic prototypes using LEGO MINDSTORMS kits, simulating real situations of nature and confronting of the computations with classical theoretical results are built. / Este trabalho tem como objetivo principal possibilitar a compreensão de conceitos físicos utilizando fundamentos básicos de matemática. Neste sentido, pretende-se evidenciar tanto os fenômenos que ocorrem na natureza quanto os fenômenos que ocorrem em manipulações de laboratórios. No presente estudo, é possível perceber que a matemática é de fundamental importância no estudo dos fenômenos físicos. Um vasto estudo é feito acerca de conceitos matemáticos que, em seguida, serão aplicados à vários tipos de problemas, sendo possível compreender aspectos fundamentais envolvendo grandezas físicas. Com o objetivo de vivenciar as aplicações na prática, são construídos protótipos robóticos utilizando os kits LEGO MINDSTORMS, simulando situações reais da natureza e confrontando os cálculos com resultados teóricos clássicos.

The aim of this study was to examine the legal guardians' view on their children’s curiosity and interests towards physical phenomena. The study was carried out by the help of surveys that were sent to the legal guardians in both paper and digital form. The questions that were answered brings up children’s questions and interests towards physics, factors that encourage curiosities and interests, as well as the legal guardians'  view on what knowledge they find the most important for their children to have. The surveys were collected and compilated using bar charts. The result of this study shows that children in preschool age show an interest and curiosity towards physics. It also appeared that the teachers' engagements as well as an encouraging environment with accessible material are important factors, according to the legal guardian’s view, when it comes to encouraging their children´s curiosity and interests towards physics. The legal guardians consider that it is important that their children are being taught physics in preschool. / Syftet med denna studie var att undersöka vårdnadshavarnas syn på deras barns nyfikenhet och intresse för fysikaliska fenomen. Studien genomfördes med hjälp av enkäter som skickades ut till vårdnadshavarna både i pappersform och som webbenkät. Frågorna som besvarades tar upp barns frågor och intresse för fysik, vad som främjar barns nyfikenhet och intresse samt vad vårdnadshavarna upplever är viktigt att barnen får kunskaper om. Enkäterna samlades in och sammanställdes i form av stapeldiagram. Resultatet av denna undersökning visar att barn i förskoleåldern visar ett intresse och en nyfikenhet för fysik. Det framkom också att pedagogernas engagemang samt en uppmuntrande miljö med tillgängligt material är viktiga faktorer enligt vårdnadshavarna när det gäller att främja barns nyfikenhet och intresse för fysik. Vårdnadshavarna lyfter att det är viktigt att deras barn får med sig kunskaper inom fysik från förskolan.

The purpose of the study is to contribute knowledge about how 2-4-year-oldsexplore the physical phenomena of floating and sinking, and how a practicalactivity can contribute to development and learning. To respond to the study,observation was chosen as the method where a designed activity with thevariation theory as support was conducted in three groups of children, theactivity was then divided into four phases for us students to get a clearerstructure. The theory was made visible by making the phenomena the objectof learning in the exploration. The children themselves got to explore and thinkabout which aspects determined whether something floated or sank usingvariations on similar objects. The three activities were filmed and lateranalyzed using the research questions and categories that emerged using theanswers from the four phases.The result shows that it is possible to perform a float and sink activity with theyounger children in preschool. Something that connects to Jean Piaget´s stagetheory was that the youngest children stopped their exploration when theycame up with a hypothesis and they saw what was happening. Our result showsthat, when they are four years old, they start to come up with explanations forthe hypotheses they have given about how an object behaves in a certain wayin water. The most common thing that the children referred to was the weightof the object. They concluded that an object sank because it was heavy, butthey also reasoned that an object floated because it was heavy. This shows thatthey don’t have the answers fully but the thoughts and the will to understand. / Syftet med studien är att bidra med kunskap om hur 2–4-åringar utforskar defysikaliska fenomenen flyta och sjunka samt hur en praktisk aktivitet kan bidratill utveckling och lärande. För att möta studiens syfte valdes observation sommetod där en designad aktivitet med variationsteorin som stöd genomfördes itre barngrupper, aktiviteten delades sen in i fyra faser för oss studenter för attfå en tydligare struktur. Teorin synliggjordes genom att fenomenen blevlärandeobjektet i utforskandet. Barnen fick själva utforska och fundera på vilkaaspekter som avgjorde om något flöt eller sjönk med hjälp av variationer påföremål som liknade varandra. De tre aktiviteterna filmades och analyseradessenare med hjälp av studiens frågeställningar och kategorier som uppkom medhjälp av det som resultatet visade från de fyra faserna.Resultatet visar att det är möjligt att utföra en flyta och sjunka-aktivitet med deyngre barnen i förskolan. Något som knyter an till Jean Piagets stadieteori varatt de yngsta barnen stannar sitt utforskande vid att komma med en hypotesoch ser vad det är som händer. Först när de fyllt fyra år börjar de komma medförklaringar till de hypoteser de gett om hur ett föremål beter sig på ett visstsätt i vatten. Det vanligaste som barnen refererade till var föremålets vikt, dekom fram till att ett föremål sjönk för att det var tungt men de resonerade ävenatt ett föremål flöt för att det var tungt. Detta visar på att de inte har svaren heltmen funderingarna och viljan att förstå finns.

Cette thèse s’inscrit dans le domaine de l'intelligence ambiante (Ambient Intelligence - AmI). Les systèmes AmI sont des systèmes interactifs composés de plusieurs éléments hétérogènes. Principalement : les capteurs et les effecteurs.D'un point de vue fonctionnel, l'objectif des systèmes AmI est d'activer certains effecteurs, sur la base des mesures des capteurs. Toutefois, les capteurs et les effecteurs peuvent subir des défaillances. Notre motivation dans cette thèse est de munir les systèmes AmI de capacités d'auto-détection des pannes.Les ressources physiques ne sont pas nécessairement connues au moment de la conception, mais elles sont plutôt découvertes dynamiquement lors de l'exécution. Il est donc impossible d’appliquer les techniques classiques pour prédéterminer des boucles de régulation ad-hoc.Nous proposons une nouvelle approche où la stratégie de détection de défaillances est déterminée dynamiquement lors de l'exécution. Pour cela, les couplages entre capteurs et effecteurs sont déduits automatiquement lors de l’exécution. Ceci est rendu possible par la modélisation des caractéristiques des capteurs, des effecteurs, ainsi que des phénomènes physiques (que nous appelons effets) qui sont attendus dans l'environnement ambiant suite à une action d’un effecteur. Ces effets sont utilisés en run-time pour lier les effecteurs (produisant les effets) avec les capteurs correspondants (détectant ces effets). Nous introduisons une plateforme de détection des pannes qui génère à l’exécution un modèle de prédiction des valeurs attendues sur les capteurs. Ce modèle, de nature hétérogène (il mêle flots de données et automates finis) est exécuté par un outil adapté (ModHel’X) de façon à fournir les valeurs attendues à chaque instant. Notre plateforme compare alors ces valeurs avec les valeurs réellement mesurées de façon à détecter les défaillances. / This thesis takes place in the field of Ambient Intelligence (AmI). AmI Systems are interactive systems composed of many heterogeneous components. From a hardware perspective these components can be divided into two main classes: sensors, using which the system observes its surroundings, and actuators, through which the system acts upon its surroundings in order to execute specific tasks.From a functional point of view, the goal of AmI Systems is to activate some actuators, based on data provided by some sensors. However, sensors and actuators may suffer failures. Our motivation in this thesis is to equip ambient systems with self fault detection capabilities. One of the particularities of AmI systems is that instances of physical resources (mainly sensors and actuators) are not necessarily known at design time; instead they are dynamically discovered at run-time. In consequence, one could not apply classical control theory to pre-determine closed control loops using the available sensors. We propose an approach in which the fault detection and diagnosis in AmI systems is dynamically done at run-time, while decoupling actuators and sensors at design time. We introduce a Fault Detection and Diagnosis framework modeling the generic characteristics of actuators and sensors, and the physical effects that are expected on the physical environment when a given action is performed by the system's actuators. These effects are then used at run-time to link actuators (that produce them) with the corresponding sensors (that detect them). Most importantly the mathematical model describing each effect allows the calculation of the expected readings of sensors. Comparing the predicted values with the actual values provided by sensors allows us to achieve fault-detection.

The aim of this study is to investigate how preschool children, aged 3-5 years, create meaning of static electricity in an activity led by a pedagogue, how this is expressed and what part the pedagogue takes in children’s meaning making. The method used was participant observation and video camera was used to document a designed activity. The observations took place at four occasions with four different groups and the observations was conducted in different rooms of various sizes, which were provided by the preschool. Equipment used in this study are: Balloons, pvc-pipes, salt, different kinds of papers, aluminum cans and thin plastic bags. Results in this study show that the children create meaning of the activity first and foremost by exploring interplay and conversations. They solve the task at hand working together and with support of the pedagogue. The role of pedagogue in the children’s meaning making is to present tasks which have moderate levels of difficulties, and to direct the children’s focus by using questions concerning the current phenomenon. In so doing, they support the children to succeed. Factors of importance for the children’s meaning making is to be given the opportunity to explore, their curiosity, joy and being heard.

The purpose of this study is to investigate how educators in preschool view teaching physics and how it is carried out together with the children. To find out about this, the study has been conducted with help of digital questionnaires where all educators in a medium-sized municipality in central Sweden have been given the opportunity to answer. The result shows that most of the educators in the municipality feel that they miss knowledge and competence in conducting physics education in preschool. It appears that the educators who have competence in physics, find it difficult to conduct the teaching further if they are “on their own” in the team with that competence. It also appears that many educators want conditions such as tips, inspiration and competence development in order to be able to conduct good physics education together with the children. When it comes to physics education in preschool, we see that educators find it challenging to integrate that sort of education into preschool everyday life. We can also see that educators feel that it is difficult to interpret the goals of the preschool curriculum with physics and natural sciences. It appears that there is not as much planned teaching as spontaneous teaching, because it is a challenge to conduct planned teaching. The physical phenomena that educators work with the most are water, magnetism and different seasons. Finally, we see that there is a great willingness on the part of educators to develop their knowledge in how to conduct good physics education together with the children at the preschool. / Syftet med denna studie är att undersöka hur pedagoger i förskolan ser på fysikundervisning och hur den genomförs tillsammans med barnen. För att ta reda på detta har studien genomförts med hjälp av digitala enkäter där alla pedagoger i en medelstor kommun i Mellansverige fått möjligheten att svara. Resultatet visar att pedagoger i kommunen upplever att de saknar kunskap och kompetens kring att bedriva fysikundervisning i förskolan. Det framkommer att de pedagoger som har kompetens i fysik, upplever det svårt att bedriva undervisningen vidare om ingen mer i arbetslaget har samma kompetens. Det framgår också att många önskar förutsättningar som tips, inspiration och kompetensutveckling för att kunna bedriva bra fysikundervisning tillsammans med barnen. När det gäller fysikundervisning i förskolan ser vi att pedagoger upplever det utmanande att integrera fysikundervisning i förskolans vardag. Vi kan också se att pedagoger känner att det är svårt att tolka målen i förskolans läroplan med kopplingar till fysik och naturvetenskap. Det framkommer att det inte bedrivs lika mycket planerad undervisning som det bedrivs spontan undervisning. Detta för att pedagoger upplever det som en utmaning att bedriva planerad undervisning. De fysikaliska fenomen som pedagogerna arbetar med mest är vatten, magnetism och årstider. Avslutningsvis ser vi att det finns en stor vilja hos pedagoger att utveckla sina kunskaper kring hur de ska bedriva bra fysikundervisning tillsammans med barnen på förskolan, samt att pedagoger vill ha en kontinuerlig kompetensutbildning.