The aim of this project was to develop a Numerical model simulating the global transport of air pollution. The model currently used by SMHI, the Swedish Meteorological and Hydrological Institute, was intended to perform such simulations at regional scales. However, the usage of a grid based on longitudes and latitudes makes this model work poorly in global simulations. The problem with this grid is that the nodes are concentrated near the North and South Poles. Due to this characteristic, the Courant, Friedrich and Lewy-condition for numerical stability puts a sharp bound on the timestep length.

This thesis has been a part of Forsmarks Kraftgrupp AB's evaluation of a turbulencemodel used in simulation of turbulent flow called PRNS (Partially Resolved NumericalSimulation). This model has promising properties and may be of use in savingcomputational resources. The purpose of this thesis was to analyze this model andcompare it with industrially applied models such as k-omega SST and LES (Large EddySimulations).PRNS works as a hybrid of the k-omega SST and DNS (Direct Numerical Simulation)where a constant, RCP (Resolution Control Parameter) with a value between 0 and 1are selected. This constant is then used in the calculations and determines thebehavior of the simulation. When RCP is set to zero the equation are the same as fora DNS simulation and when RCP is set to one the equations for k-omega SST issolved.

This study examines the background and nature of the credit default index swaption (CDIS) and presentsrelevant methods for modelling credit risk. A CDIS is a credit derivative contract that gives the buyerright to enter into a credit default index swap (CDS index) contract at a given point in time. ACDS index, in turn, is a multi-name credit default swap (CDS). Within the eld of research, thisthesis identi es the CDIS pricing models presented by Jackson (2005), Rutkowski & Armstrong (2009)and Morini & Brigo (2011) as the most recognized and developed. These models are evaluated byreconstruction in a numerical software environment.

This master thesis covers the seasonal planning of a small scale hydropower system. The system in this study is owned and operated by Mälarenergi Vattenkraft AB. The total system consists of 4 different main rivers with 24 hydropower stations and several dams. The total installed power in the system is 43.75 MW. Most of the hydropower stations are regarded as small scale hydropower stations and thus entitled to green certificates.In this report the issue of planning is formulated as an optimization problem.

This master thesis is made of two parts. The first part concerns the method and results ofdesigning a motion control system for a piece of research-equipment called BIRGIT. Theequipment is made to be used for research on eyemovements. In the second part, a computermodel of a part of the balance organ in the inner-ear is developed. The work has been done atthe Bernadotte laboratory at S:t Erik Eye Hospital.The equipment the control system is made for is a so-called rotationchair.

This thesis deals with numerical simulation of earth pressure against tubular bridges in the software Plaxis. Plaxis is a FEM (Finite Element Method) software based on numerical calculations for which approximate solutions are developed through an iterative process. The program is specifically designed for soil and rock mechanical tests, such as voltage and deformation calculations in soil.The Royal Institute of Technology conducted in 2005, field tests on tubular bridges of corrugated steel, which was part of Ersa Bayoglu Fleners PhD (Bayoglu Flener, 2009). She studied how two different tubular bridges deformed during installation and filling. Tests and measurements were made during filling.

The thermal response of a borehole field is often described by non?dimensional response factors called gfunctions.The g?function was firstly generated as a numerical solution based on SBM (Superposition BoreholeModel). An analytical approach, the FLS (Finite Line Source), is also accepted for generating the g?function. In thiswork the potential to numerically produce g?functions is studied for circular borehole fields using the commercialsoftware COMSOL.

Efficient numerical methods for option pricing is an active field of research. This project has the goal to examine possible ways to improve an established method of numerical pricing. The method is based on an adaptive finite difference method in price and uses the backwards differentiation formula of order 2, BDF2, in time. The project will focus on improvements to the time integration through implementation of discontinuous Galerkin methods, dG. Empirical convergence and accuracy results are obtained for equidistant dG-methods up to order 3 and performance is compared to BDF2.

Reading difficulties is the most common learning difficulty in the western world and it is common that people with reading disabilities also exhibit arithmetic difficulties. Different theories about the cause of the relationship exists, one theory describes the importance of good phonological ability in reading as well as in arithmetic, while another theory describes the importance of a reliable number system and that only a subgroup of students with reading disabilities also have difficulties with arithmetic. The purpose of this study is to investigate how students with reading difficulties (RD), without any known mathematical difficulties, perform on mathematical tasks relative to a control group. The study was theoretically grounded on the Triple code model (Dehaene, 1992), which is a model for numerical information processing that describes how various numerical and arithmetic tasks are processed through three distinct representation systems in the brain, a verbal and a visual representation system and a quantity system. Reading skills, phonological skills, arithmetic skills and number processing skills were examined in 61 students through a variety of tests.

Stratego is a boardgame not very different from chess, that contains hidden information. Because of this, existing programs play at beginner level. The purpose of this thesis is to adjust a minimax algorithm so that it passes the demands of Stratego, and then build a Stratego agent around it. Tests with existing minimax algorithms leads to the development p-e-minimax. This algorithm uses two different values in its nodes to simulate the different information available to the agent and its opponent.

Sparse matrices are often used in numerical algorithms that solve linear equation systems. Many methods for storing sparse matrices have been proposed and implemented during the years. These methods focus primarily on minimizing the total memory consumption and the time that it takes to store a sparse matrix. This report researches the available storage methods for sparse unstructured matrices. The formats that are researched and implemented are COO, CRS and ELL.

The thesis deals with three document retrieval models based on logic: the Boolean model,the fuzzy model and the Van Rijsbergen model.In Chapter 1, the author presents the purpose of the thesis. This is to give the logical foundationof the models, to describe them and to examine them critically. In Chapter 2, some importantnotions in document retrieval are presented. Chapter 3 is devoted to the Boolean model, Chapter4 to the fuzzy model and Chapter 5 to the Van Rijsbergen model.These three chapters are organized in the same way. First, the logical foundation of the modelis given.

Simulation of different systems can be done using a graphical model description of the system based on block diagrams. The simulation software Matlab/Simulink offers a lot of possibilities to describe a huge number of systems, which can be linear as well as nonlinear. The simulation using Matlab/Simulink is done by integration based on different kinds of numerical methods.When nonlinear Simulink-models are simulated, it is often interesting to apply a Kalman filter to handle the noise that may occur within the process as well as corrupting the measurement. However, application of such a filter leads to an extensive time-consumption despite using fast computers. The reason is that the existing Matlab functions are not constructed for time optimal evaluation.

This report aims to provide an insight into the particle physics of today, and into the research that goes on within the field. The focus is partly on the recent discovery of the Higgs boson, and partly on how software can be used to simulate processes in particle accelerators. Basic concepts of particle physics and the search for the Higgs boson are discussed, and experimental results, including those from the Large Hadron Collider, are compared with simulations made in MadGraph 5. Furthermore, simple new models of particle physics are created in FeynRules, in order to make simulations based on the models. To support the presentations of these aspects, some of the underlying theory is built from the ground up.

Studie är baserad på Siegler & Ramani (2008) ?Playing linear numerical board games promotes low-income child­ren´s numerical development?. Syfte är att undersöka om det med intensivträning (i form av ett linjärt tärningsspel) går att stimulera sexåriga barns talförståelse inom talområdet 1-10. Metoderna som valts är fältexperiment och observation. Fält­experimentet påvisar att intensivträning med ett tärningsspel, utfört under 4 stycken 15 minuters lektioner under en tvåveckors period, tydligt kan förbättra barns talförståelse medan observationen visar att utfallet påverkas av pedagogens olika yrkesverktyg samt undervis­ningens organisation (en-till-en undervisning).