Nesta Tese desenvolvemos várias abordagens "Darbouxianas"para buscar integrais primeiras (elementares e Liouvillianas) de equações diferenciais ordinárias de segunda ordem (2EDOs) racionais. Os algoritmos (semi-algoritmos) que desenvolvemos seguem a linha do trabalho de Prelle e Singer. Basicamente, os métodos que buscam integrais primeiras elementares são uma extensão da técnica desenvolvida por Prelle e Singer para encontrar soluções elementares de equações diferenciais ordinárias de primeira ordem (1EDOs) racionais. O procedimento que lida com 2EDOs racionais que apresentam integrais primeiras Liouvillianas é baseado em uma extensão ao nosso método para encontrar soluções Liouvillianas de 1EDOs racionais. A ideia fundamental por tras do nosso trabalho consiste em que os fatores integrantes para 1-formas polinomiais geradas pela diferenciação de funções elementares e Liouvillianas são formados por certos polinômios denominados polinômios de Darboux. Vamos mostrar como combinar esses polinômios de Darboux para construir fatores integrantes e, de posse deles, determinar integrais primeiras. Vamos ainda discutir algumas implementações computacionais dos semi-algoritmos.

<p>In case of the PDE's the concept of solving by separation of variables</p><p>has a well defined meaning. One seeks a solution in a form of a</p><p>product or sum and tries to build the general solution out of these</p><p>particular solutions. There are also known systems of second order</p><p>ODE's describing potential motions and certain rigid bodies that are</p><p>considered to be separable. However, in those cases, the concept of</p><p>separation of variables is more elusive; no general definition is</p><p>given.</p><p>In this thesis we study how these systems of equations separate and find that their separation usually can be reduced to sequential separation of single first order ODE´s. However, it appears that other mechanisms of separability are possible.</p>

<p>This research investigates and reveals the condition of outdoor education (ODE) in general in two specific countries, Cyprus and Sweden. Some more specific questions that this research tries to answer are:</p><p>· What are some differences in ODE development between Sweden and Cyprus?</p><p>· What are the opinions of teachers in Cyprus and Sweden with respect to ODE?</p><p>· What are the conditions in Swedish and Cypriot schools that affect the development and implementation of ODE in schools? </p><p>· What are some future plans for ODE in Cyprus based on these results?</p><p>For the conduction of this research questionnaires were delivered and filled out from teachers of primary school for each country. The questionnaire was consisted from sixteen questions and includes two types of questions, ordinary scale questions and a combination if ordinary scale question with open type questions.</p><p>The outcomes of the research generally show a positive attitude from behalf of the teachers towards ODE and a bigger acquaintance of Swedish teachers with the subject in compared to Cypriot teachers.</p><p>However teachers seem to have also some reservations towards some issues concerning ODE. The research also reveals the gap in the field of training opportunities-especially in Cyprus, and also the teacher’s belief in the importance of training. The important role of factors like tradition, culture and different educational systems in the two countries concerning ODE is also stress out. Taking in mind the outcomes some comments and suggestions for future plants are discussed. </p>

<p>This is a masters thesis (20p) in computer science at the University of Linköping. This thesis will give an introduction to what a physics engine is and what it consist of. It will put some engines under the magnifying glass and test them in a couple of runtime tests. Two cutting edge commercial physics engines have been examined, trying to predict the future of physics engines. From the research and test results, an interface for physics engine independency has been implemented for a company called Craft Animations in Gothenburg, Sweden.</p>

This research investigates and reveals the condition of outdoor education (ODE) in general in two specific countries, Cyprus and Sweden. Some more specific questions that this research tries to answer are: · What are some differences in ODE development between Sweden and Cyprus? · What are the opinions of teachers in Cyprus and Sweden with respect to ODE? · What are the conditions in Swedish and Cypriot schools that affect the development and implementation of ODE in schools? · What are some future plans for ODE in Cyprus based on these results? For the conduction of this research questionnaires were delivered and filled out from teachers of primary school for each country. The questionnaire was consisted from sixteen questions and includes two types of questions, ordinary scale questions and a combination if ordinary scale question with open type questions. The outcomes of the research generally show a positive attitude from behalf of the teachers towards ODE and a bigger acquaintance of Swedish teachers with the subject in compared to Cypriot teachers. However teachers seem to have also some reservations towards some issues concerning ODE. The research also reveals the gap in the field of training opportunities-especially in Cyprus, and also the teacher’s belief in the importance of training. The important role of factors like tradition, culture and different educational systems in the two countries concerning ODE is also stress out. Taking in mind the outcomes some comments and suggestions for future plants are discussed.

In case of the PDE's the concept of solving by separation of variables has a well defined meaning. One seeks a solution in a form of a product or sum and tries to build the general solution out of these particular solutions. There are also known systems of second order ODE's describing potential motions and certain rigid bodies that are considered to be separable. However, in those cases, the concept of separation of variables is more elusive; no general definition is given. In this thesis we study how these systems of equations separate and find that their separation usually can be reduced to sequential separation of single first order ODE´s. However, it appears that other mechanisms of separability are possible.

Conventional coupling paradigms used nowadays to couple various physics components in reactor analysis problems can be inconsistent in their treatment of the nonlinear terms. This leads to usage of smaller time steps to maintain stability and accuracy requirements thereby increasing the computational time. These inconsistencies can be overcome using better approximations to the nonlinear operator in a time stepping strategy to regain the lost accuracy. This research aims at finding remedies that provide consistent coupling and time stepping strategies with good stability properties and higher orders of accuracy. Consistent coupling strategies, namely predictive and accelerated methods, were introduced for several reactor transient accident problems and the performance was analyzed for a 0-D and 1-D model. The results indicate that consistent approximations can be made to enhance the overall accuracy in conventional codes with such simple nonintrusive techniques. A detailed analysis of a monoblock coupling strategy using time adaptation was also implemented for several higher order Implicit Runge-Kutta (IRK) schemes. The conclusion from the results indicate that adaptive time stepping provided better accuracy and reliability in the solution fields than constant stepping methods even during discontinuities in the transients. Also, the computational and the total memory requirements for such schemes make them attractive alternatives to be used for conventional coupling codes.

Zugl.: Kairo, Univ., Diss., 2004

A presente dissertação é fruto da pesquisa de mestrado realizada sobre o poema Ode marítima, de Álvaro de Campos, heterônimo do poeta português Fernando Pessoa. O poema foi estudado à luz de considerações teóricas que pudessem sustentar o teor artístico do citado poema, para além de um posicionamento estritamente analítico. Em outras palavras, as contribuições teóricas de Walter Benjamin, Philippe Lacoue-Labarthe, Theodor W. Adorno, entre outros, visa propocionar um discurso de pesquisa que seja poético, respeitando a manifestação literária em questão o poema. Nesse sentido, Ode marítima apresentou, ao longo da pesquisa, diferentes temas. Tais temas foram estudados, com o embasamento teórico referido, separadamente. São eles: Imaginação, Cais Absoluto, Sonho, Força e Infância. Para cada tema, um capítulo foi elaborado. Todos os temas pesquisados confluem para a apreensão da poética de Álvaro de Campos uma vez que Ode marítima é um poema singular e fundamental da obra poética do citado heterônimo. Desse modo, a pesquisa realizada não se limita à abordagem do citado poema, mas alcança demais poemas de Álvaro de Campos, de modo que se torna possível conjeturar acerca da poesia deste heterônimo. Partindo, portanto, de um poema, a pesquisa pretende poder dimensionar a obra de Álvaro de Campos, pontuando suas particularidades trazidas pela Ode marítima, mas tendo ciência de que trata-se de uma proposta entre tantas outras válidas e enriquecedoras. / This dissertation is the result of the master's research done about the poem "Ode marítima" by Álvaro de Campos, Fernando Pessoas heteronymous. The poem was studied under theoretical considerations that could sustain the artistic content of that poem. In other words, the theoretical contributions by Walter Benjamin, Philippe Lacoue-Labarthe, Theodor W. Adorno, etc, aims to provide a poetic research discourse, respecting the literary manifestation in question the poem. During the research "Ode marítima" showed different themes. These themes were studied separately. They are: "Imagination," "Absolute Pier", "Dream", "Strength" and "Childhood". For each subject a chapter has been prepared. All subjects studied converge to the apprehension of Álvaro de Campos "Ode marítima" as a poem that contains the singularity of this heteronymous. Thus, the survey reaches other poems by Álvaro de Campos, making possible the conjecture about the poetry of this heteronymous. The research aims to gain the studies of Alvaro de Campos poetry, pointing out its peculiarities, as done about by the "Ode marítima" and being aware that this is one proposal among many others as valid and as enriching as this one

abstract: Several physical systems exist in the real world that involve continuous as well as discrete changes. These range from natural dynamic systems like the system of a bouncing ball to robotic dynamic systems such as planning the motion of a robot across obstacles. The key aspects of effectively describing such dynamic systems is to be able to plan and verify the evolution of the continuous components of the system while simultaneously maintaining critical constraints. Developing a framework that can effectively represent and find solutions to such physical systems prove to be highly advantageous. Both hybrid automata and action languages are formal models for describing the evolution of dynamic systems. The action language C+ is a rich and expressive language framework to formalize physical systems, but can be used only with physical systems in the discrete domain and is limited in its support of continuous domain components of such systems. Hybrid Automata is a well established formalism used to represent such complex physical systems at a theoretical level, however it is not expressive enough to capture the complex relations between the components of the system the way C+ does. This thesis will focus on establishing a formal relationship between these two formalisms by showing how to succinctly represent Hybrid Automata in an action language which in turn is defined as a high-level notation for answer set programming modulo theories (ASPMT) --- an extension of answer set programs in the first-order level. Furthermore, this encoding framework is shown to be more effective and expressive than Hybrid Automata by highlighting its ability in allowing states of a hybrid transition system to be defined by complex relations among components that would otherwise be abstracted away in Hybrid Automata. The framework is further realized in the implementation of the system CPLUS2ASPMT, which takes advantage of state of the art ODE(Ordinary Differential Equations) based SMT solver dReal to provide support for ODE based evolution of continuous components of a dynamic system. / Dissertation/Thesis / Masters Thesis Computer Science 2017