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This study explores the application of object detection models for detecting Arctic Foxes in camera trap images, a crucial step towards automating wildlife monitoring and enhancing conservation efforts. The study involved training models on You Only Look Once version 7(YOLOv7) architecture across different locations using k-fold cross-validation technique and evaluating their performance in terms of mean Average Precision (mAP), precision, and recall. The models were tested on both validation and unseen data to assess their accuracy and generalizability. The findings revealed that while certain models performed well on validation data, their effectiveness varied when applied to unseen data, with significant differences in performance across the datasets. While one of the datasets demonstrated the highest precision (88%), and recall (94%) on validation data, another one showed superior generalizability on unseen data (precision 76%, recall 95%). The models developed in this study can aid in the efficient identification of Arctic Foxes in diverse locations. However, the study also identifies limitations related to dataset diversity and environmental variability, suggesting the need for future research to focus on training models during different seasons and having different aged Arctic Foxes. Recommendations include expanding dataset diversity, exploring advanced object detection architectures to go one step further and detect Arctic Foxes with skin diseases, and testing the models in varied field conditions.

Text in Afrikaans / A study of the philosophical and historical foundations of infinity highlights the problematic development of infinity. Aristotle distinguished between potential and actual infinity, but rejected the latter. Indeed, the interpretation of actual infinity leads to contradictions as seen in the paradoxes of Zeno. It is difficult for a human being to understand actual infinity. Our logical schemes are adapted to finite objects and events. Research shows that students focus primarily on infinity as a dynamic or neverending process. Individuals may have contradictory intuitive thoughts at different times without being aware of cognitive conflict. The intuitive thoughts of students about both the actual (at once) infinite and potential (successive) infinity are very complex. The problematic nature of actual infinity and the contradictory intuitive cognition should be the starting point in the teaching of the concept infinity. / Educational Studies / M.Ed. (Mathematic Education)

This master thesis investigates the possibility to create a machine vision solution for the automation of earth-moving machines. This research was done as without some type of vision system it will not be possible to create a fully autonomous earth moving machine that can safely be used around humans or other machines. Cameras were used as the primary sensors as they are cheap, provide high resolution and is the type of sensor that most closely mimic the human vision system. The purpose of this master thesis was to use existing real time object detectors together with transfer learning and examine if they can successfully be used to extract information in environments such as construction, forestry and mining. The amount of data needed to successfully train a real time object detector was also investigated. Furthermore, the thesis examines if there are specifically difficult situations for the defined object detector, how reliable the object detector is and finally how to use service-oriented architecture principles can be used to create deep learning systems. To investigate the questions formulated above, three data sets were created where different properties were varied. These properties were light conditions, ground material and dump truck orientation. The data sets were created using a toy dump truck together with a similarly sized wheel loader with a camera mounted on the roof of its cab. The first data set contained only indoor images where the dump truck was placed in different orientations but neither the light nor the ground material changed. The second data set contained images were the light source was kept constant, but the dump truck orientation and ground materials changed. The last data set contained images where all property were varied. The real time object detector YOLOv3 was used to examine how a real time object detector would perform depending on which one of the three data sets it was trained using. No matter the data set, it was possible to train a model to perform real time object detection. Using a Nvidia 980 TI the inference time of the model was around 22 ms, which is more than enough to be able to classify videos running at 30 fps. All three data sets converged to a training loss of around 0.10. The data set which contained more varied data, such as the data set where all properties were changed, performed considerably better reaching a validation loss of 0.164 compared to the indoor data set, containing the least varied data, only reached a validation loss of 0.257. The size of the data set was also a factor in the performance, however it was not as important as having varied data. The result also showed that all three data sets could reach a mAP score of around 0.98 using transfer learning.

<p>Tillskillnad mot de flesta Västernfilmerna valde manusförfattarna till C'era una volta il West att införa en kvinnlig karaktär i en av de större rollerna. Uppsatsen undersöker utifrån ett feministiskt perspektiv med texter av Laura Mulvey och Mary Ann Doane som utgångspunkt representationerna av filmens fyra huvudkaraktärer. I den första delen av uppsatsen diskuteras Västernfilmen i stort med extra fokus på Sergio Leones filmskapande. Därefter följer en redogörelse av de utvalda texterna vilka sedan används under läsningen av filmen i analysdelen.</p>

Optimal control problems (OCPs) governed by convection dominated diffusion-convection-reaction equations arise in many science and engineering applications such as shape optimization of the technological devices, identification of parameters in environmental processes and flow control problems. A characteristic feature of convection dominated optimization problems is the presence of sharp layers. In this case, the Galerkin finite element method performs poorly and leads to oscillatory solutions. Hence, these problems require stabilization techniques to resolve boundary and interior layers accurately. The Streamline Upwind Petrov-Galerkin (SUPG) method is one of the most popular stabilization technique for solving convection dominated OCPs. The focus of this thesis is the application and analysis of the SUPG method for distributed and boundary OCPs governed by evolutionary diffusion-convection-reaction equations. There are two approaches for solving these problems: optimize-then-discretize and discretize-then-optimize. For the optimize-then-discretize method, the time-dependent OCPs is transformed to a biharmonic equation, where space and time are treated equally. The resulting optimality system is solved by the finite element package COMSOL. For the discretize-then-optimize approach, we have used the so called allv at-once method, where the fully discrete optimality system is solved as a saddle point problem at once for all time steps. A priori error bounds are derived for the state, adjoint, and controls by applying linear finite element discretization with SUPG method in space and using backward Euler, Crank- Nicolson and semi-implicit methods in time. The stabilization parameter is chosen for the convection dominated problem so that the error bounds are balanced to obtain L2 error estimates. Numerical examples with and without control constraints for distributed and boundary control problems confirm the effectiveness of both approaches and confirm a priori error estimates for the discretize-then-optimize approach.

Tillskillnad mot de flesta Västernfilmerna valde manusförfattarna till C'era una volta il West att införa en kvinnlig karaktär i en av de större rollerna. Uppsatsen undersöker utifrån ett feministiskt perspektiv med texter av Laura Mulvey och Mary Ann Doane som utgångspunkt representationerna av filmens fyra huvudkaraktärer. I den första delen av uppsatsen diskuteras Västernfilmen i stort med extra fokus på Sergio Leones filmskapande. Därefter följer en redogörelse av de utvalda texterna vilka sedan används under läsningen av filmen i analysdelen.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Early lactation in dairy cows involves metabolic changes, being mobilization of corporal reserves very common. So the objective of this work is to study indexes of negative energetic balance in dairy cows on early lactation, in two different energy levels. For this, 20 cows were distributed in a randomized complete block design, resulting in 2 treatments: T1 one milking per day for 8 weeks on the beginning of lactation and T2 two milkings for the same period of time. In animals, it was measured live weight, body condition scoring, skinfold thickness, being also collected blood samples for non-esterified fatty acids, urea, glucose, acetoacetate and Dβ-Hydroxybutirate analyses. It was also realized urea dilution measurements. As a result dry matter intake wasn´t different between treatments, milk production and milk solids in kg were lower for T1. For differences analyses T1 resulted in a better energy balance for the treatment period (P = 0.0002), obtaining the opposite result for residual period (P = 0.0423). Talking about corporal characteristics, corporal protein was statistically different between the treatments only for residual period, being higher for T1 (P = 0.0463), meanwhile in blood measures, non-esterified fatty acids (P = 0.0352) and Dβ-Hydroxybutirate (P = 0.0004), were lower for T1, for treatment period. Dβ-Hydroxybutirate didn´t show relation with energy balance, so more studies must be done. / Período inicial da lactação em vacas leiteiras envolve várias modulações a nível metabólico, sendo mobilização de reservas corporais característico neste momento. Portanto, o objetivo com este trabalho é estudar indicadores de balanço energético negativo em vacas leiteiras em período inicial de lactação, mantidas sob dois níveis de balanço energético. Para isso, 20 vacas foram arranjadas em um delineamento blocos ao acaso, sendo aplicados dois tratamentos: T1 uma ordenha diária durante oito semanas iniciais de lactação; T2 duas ordenhas diárias durante oito semanas iniciais de lactação. Nos animais foi determinado peso vivo, escore de condição corporal, espessura de gordura subcutânea; sendo ainda coletadas amostras de sangue, para análise de ácidos graxos não esterificados, ureia, glicose, acetoacetato e Dβ-Hidroxibutirato. Técnica de diluição de ureia também foi realizada. Consumo de matéria seca não diferiu entre os grupos. Produção de leite e kilogramas de sólidos foram menores para T1. Pelas análises das diferenças T1 apresentou melhor balanço energético em período de tratamento (P = 0,0002), invertendo a relação para o período residual (P = 0,0423). Para as características corporais, proteína corporal diferiu no período residual sendo maior para T1 (P = 0,0463), já das mensurações sanguíneas, ácidos graxos não esterificados (P = 0,0352) e Dβ-Hidroxibutirato (P = 0,0004) foram menores no período de tratamento em T1. Dβ-Hidroxibutirato não apresentou relação com balanço energético, assim mais estudos deverão ser realizados.

Text in Afrikaans / A study of the philosophical and historical foundations of infinity highlights the problematic development of infinity. Aristotle distinguished between potential and actual infinity, but rejected the latter. Indeed, the interpretation of actual infinity leads to contradictions as seen in the paradoxes of Zeno. It is difficult for a human being to understand actual infinity. Our logical schemes are adapted to finite objects and events. Research shows that students focus primarily on infinity as a dynamic or neverending process. Individuals may have contradictory intuitive thoughts at different times without being aware of cognitive conflict. The intuitive thoughts of students about both the actual (at once) infinite and potential (successive) infinity are very complex. The problematic nature of actual infinity and the contradictory intuitive cognition should be the starting point in the teaching of the concept infinity. / Educational Studies / M.Ed. (Mathematic Education)

The master thesis deals with hydraulic characteristics of once-through boilers and describes the problems which may arise during the flow of water through the evaporator. Especially the formation of aperiodic instability of the evaporator and hydraulic uniformity amongst every steam generating tube. The thesis describes parameters, which cause these problems, and solutions how to deal with them. The calculation has been done for evaporator of the boiler called K2 located in power station in Chvaletice.