This thesis that implemented Monte Carlo path tracing and voxel cone tracing for global illumination on GPU compared the performance and visual result. The Monte Carlo path tracing algorithm is implemented in CUDA to do parallel computing on GPU and accelerate the computing speed. The voxel cone tracing, a global illumination algorithm for real-time computing, runs on OpenGL through the GPU graphics pipeline. The results show that the Monte Carlo Path Tracing on CPU single core takes over 10 hours, around 4 hours with 4 cores, on GPU it takes around 48 minutes, while the voxel cone tracing on the same GPU takes 2 ms. The quality of the image generated by the Monte Carlo path tracing contains much more transparent, reflection, and shadow details than that using the voxel cone tracing algorithm. / <p>Examensarbetet är utfört vid Institutionen för teknik och naturvetenskap (ITN) vid Tekniska fakulteten, Linköpings universitet</p>

In computer graphics applications, the choice and implementation of a rendering technique is crucial when targeting real-time performance. Traditionally, rasterization-based approaches have dominated the real-time sector. Other algorithms were simply too slow to compete on consumer graphics hardware. With the addition of hardware support for ray-intersection calculations on modern GPUs, hybrid ray tracing/rasterization and purely ray tracing approaches have become possible in real-time as well. Industry real-time graphics applications, namely games, have been exploring these different rendering techniques with great levels of success. The addition of ray tracing into the graphics developer’s toolkit has without a doubt increased what level of graphical fidelity is achievable in real-time. In this thesis, three rendering techniques are implemented in a custom rendering engine built on the Vulkan® Explicit API. Each technique represents a different family of modern real-time rendering algorithms. A largely rasterization-based method, a hybrid ray tracing/rasterization method, and a method solely using ray tracing. Both the hybrid and ray tracing exclusive approach rely on the ReSTIR algorithm for lighting calculations. Analysis of the performance and render quality of these approaches reveals the trade-offs incurred by each approach, alongside the performance viability of each in a real-time setting.

La protection des opérateurs et la surveillance des ambiances de travail en cas de mise en suspension d’aérosols radioactifs, dans un local ventilé d’une installation nucléaire, requièrent la connaissance de l’évolution spatio-temporelle de la concentration en particules, en tout point du local considéré. L’estimation précise de cette concentration a fait l’objet du développement de modèles spécifiques de transport et de dépôt d’aérosols dans un local ventilé, dans le cadre d’une thèse cofinancée par l’IRSN et EDF, en collaboration avec l’IMFT. Un formalisme eulérien de glissement est utilisé pour modéliser le transport des aérosols. Celui-ci est basé sur une unique équation de transport des concentrations en particules (« Diffusion-Inertia model »). L’étude spécifique du dépôt d’aérosols en parois a permis de développer un modèle de couche limite, qui consiste à déterminer précisément le flux de dépôt de particules en parois, quels que soient le régime de dépôt et l’orientation de la surface considérée. Les modèles de transport et de dépôt finalement retenus ont été implantés dans Code_Saturne, un logiciel de mécanique des fluides. La validation de ces modèles a été effectuée à partir de données de la littérature en géométries simples, puis sur la base de campagnes expérimentales de traçage dans des locaux ventilés d’environ 30 m&#179; et 1500 m&#179;. / When particulate radioactive contamination is likely to become airborne in a ventilated room, assessment of aerosol concentration in every point of this room is important, in order to ensure protection of operators and supervision of workspaces. Thus, a model of aerosol transport and deposition has been developed as part of a project started with IRSN, EDF and IMFT. A simplified eulerian model, called “diffusion-inertia model” is used for particle transport. It contains a single transport equation of aerosol concentration. The specific study of deposition on walls has permitted to develop a boundary condition approach, which determines precisely the particle flux towards the wall in the boundary layer, for any deposition regime and surface orientation.The final transport and deposition models retained have been implemented in a CFD code called Code_Saturne. These models have been validated according to literature data in simple geometries and tracing experiments in ventilated rooms, which have been carried out in 30 m&#179; and 1500 m&#179; laboratory rooms.

This work aims at rendering 3D scene using ray tracing. It describes advantages and disadvantages of this technology and its alternation known as distributed ray tracing. Other part deals with method from different branch, which are closely related to distributed ray tracing - constructive solid geometry and procedural texturing.

Este projeto de pesquisa, que desperta a vivência e suscita questionamentos pessoais sobre os aparentes resultados da formação continuada de professores com o uso das Tecnologias Digitais de Informação e Comunicação TDIC , inicia-se com a formação introdutória para uso de software de programação para professores de informática educativa do município de São Paulo. E, em razão do rápido avanço nas relações entre as novas tecnologias e a rede, em todas as áreas socioeconômico-culturais, constata ser imprescindível expandir o conceito de fluência digital, para fortalecer o currículo Trivium contemporâneo e melhorar a situação real da educação brasileira. E questiona: qual leitura segundo a abordagem antiessencialista da tecnologia é realizada, pelo professor em formação, do software de programação, neste caso o Scratch, para utilizá-lo com seus alunos em nossas atuais escolas? Para tal investigação, utiliza-se o estudo de caso com a técnica do process tracing, adaptada à educação, de maneira a transferir a análise das causas e dos resultados para o processo em si, que é desconhecido, na criação de uma teoria. Por meio das manifestações e das atividades reais, desde a formação até a aplicação do Scratch em classe, preveem-se e testam-se evidências em mecanismo causal hipotético. Tais evidências, confirmadas ou não pelas observações em classe, por entrevistas, questionários, depoimentos e rotinas de aula, nos casos em estudo, contribuem para que se proponha a Formação Insubordinada de Professores para o uso das TDIC FoIP-TDIC. O modelo traz como premissas serem as TDIC dependentes da cultura; por meio delas, o professor pode estimular a criatividade, a consciência cidadã, a investigação e a resolução de problemas reais e relevantes, de forma a elaborar criticamente seu cotidiano. A FoIP-TDIC relativiza as evidências tidas por formadores e formandos como necessárias e/ou imprescindíveis em uma formação. Portanto, pretende ampliar ideias para a estrutura e a organização de formação inicial ou continuada do professor da educação básica, seja ela presencial ou semipresencial. Aprofundar pesquisas da FoIP-TDIC poderá contribuir para a formação rumo à Educação 4.0 em uma sociedade que se deseja solidária. / This research project, which awakens the experience and raises personal questions about the apparent results of the ongoing training of teachers with the use of Digital Information and Communication Technologies (TDIC), begins with the introductory training for the use of programming software for teachers of educational computing in the city of São Paulo. Because of the rapid progress in the relations between the new technologies and the network in all socioeconomic and cultural areas, it is essential to expand the concept of digital fluency, to strengthen the contemporary Trivium curriculum and to improve the real situation of Brazilian education. He questions: what reading - according to the antiessentialist approach of technology - is carried out by the teacher in training of programming software, in this case Scratch, to use it with his students in our current schools? For this investigation, the case study is used with the process tracing technique, adapted to education, in order to transfer the analysis of causes and results to the process itself, which is unknown, in the creation of a theory. Through the manifestations and real activities, from the formation to the application of the Scratch in class, evidence and tests in hypothetical causal mechanism are foreseen and they are tested. These evidences, confirmed or not by classroom observations, through interviews, questionnaires, statements and classroom routines, in the cases under study, contribute to the proposed Insubordinate Teacher Training for the use of TDIC - FoIP-TDIC. The model assumes that the culture-dependent TDICs are; through them, the teacher can stimulate creativity, citizen awareness, research and resolution of real and relevant problems, in order to, critically elaborate their daily lives. The FoIP-TDIC relativizes the evidences taken by trainers and trainees as necessary and / or essential in a formation. Therefore, it intends to broaden ideas for the structure and organization of initial or continuing training of the elementary school teacher, whether it is classroom or semi-presential. Deepening FoIP-TDIC research may contribute to the formation towards Education 4.0 in a society that wishes to be in solidarity.

Ziel dieser Arbeit ist es einerseits, allgemeine Erwartungen an die Bedienabläufe eines Fahrerinformationssystems zu ermitteln, welche Benutzer aus ihren Vorerfahrungen mit anderen technischen Geräten mitbringen, und andererseits zu zeigen, dass sich die Anpassung der Bedienabläufe eines Fahrerinformationssystems an diese allgemeinen Benutzererwartungen vorteilhaft auf die Gebrauchstauglichkeit des Gerätes auswirkt. Dabei wird eine Erwartung, welche in einer bestimmten Bediensituation an das Gerät besteht, verstanden als das mentale Modell von der Funktionsweise des Systems, welches der Benutzer in genau dieser Situation aus seinem schematischen Vorwissen und Merkmalen der Bedienoberfläche des zu bedienenden Gerätes bildet. In einer ersten Studie werden zunächst durch einen Vergleich mit dem konzeptuellen Modell eines bestehenden Fahrerinformationssystems diejenigen mentalen Modelle der Benutzer von Bedienabläufen identifiziert, welche interindividuell übereinstimmen. Dazu wird eine auf process tracing aufbauende, eigens entwickelte Methodik eingesetzt, welche es ebenfalls erlaubt, für diese Erwartungen diejenigen Aspekte zu ermitteln, welche unabhängig von speziellen Merkmalen des untersuchten Systems auch für Bedienabläufe eines Fahrerinformationssystems generell zutreffen. In einer nächsten Studie werden die ermittelten systemunabhängigen Benutzererwartungen verifiziert, indem aus ihnen das Bedienverhalten für ein zweites FIS mit anderem Bedienkonzept vorhergesagt wird. Dank der Verwendung des gleichen, handlungspsychologisch definierten Analyseniveaus für mentale und konzeptuelle Modelle können die verifizierten systemunabhängigen, interindividuell übereinstimmenden Benutzererwartungen als konzeptuelle Modelle in Form von Status-Übergangs-Diagrammen dargestellt und so als allgemeine Gestaltungsempfehlungen für Bedienabläufe in Fahrerinformationssystemen festgehalten werden. In einer dritten Studie werden die Bedienabläufe eines Prototypen entsprechend den allgemeinen Benutzererwartungen gestaltet und gegenüber Bedienabläufen evaluiert, welche von den Benutzererwartungen abweichen. Dabei zeigt sich, dass Bedienabläufe, welche mit den allgemeinen mentalen Modellen der Benutzer übereinstimmen, zu besseren Bedienleistungen und Systembewertung auf Seiten der Benutzer führen. Die formulierten allgemeinen Gestaltungsempfehlungen sind meist generalisierbar auf andere Domänen und die Ergebnisse dieser Arbeit bieten Ansatzpunkte für zukünftige Forschungsarbeiten. / The presented research project has two main goals: To learn about the nature of users’ general expectancies towards the operation of infotainment systems in passenger cars and to show that designing the paths of operation according to the users’ expectancies has positive effects on the usability of such systems. An expectancy at a certain point in the course of operation is understood as the mental model which the user forms of the system’s functionality in this situation on the basis of the system’s interface’s properties and his or her past experiences with other technical devices. A first study compares the conceptional model of an existing in-car infotainment system with the mental models of people using this system and thus identifies which mental models are shared interindividually by a majority of the users. The methodology used in this study was developed based on process tracing and permitted to equally identify those aspects of the mental models which are independent of the specific interaction concept of the examined system and therefore apply to the paths of operation of any in-car infotainment system in general. A next study verifies the users’ system-independent expectancies found in the first study by predicting users’ behavior during the operation of a second system with a different user interface. Both the users’ mental models and the systems’ conceptional models are analyzed and described using the same level of abstraction which is defined on the basis of action regulation theory. Thus directly comparable to the conceptional models, the users’ expectancies are described as state-transition diagrams which in turn as conceptional models represent the derived recommendations for the design of operational paths in infotainment systems. A third study uses a prototype system to evaluate paths of operation which have been designed according to the general recommendations versus paths of operation which deviate from the users’ expectancies. The results of this third study show that a system with paths of operation matching the users’ general mental models permits better user performance and leads to greater customer satisfaction. The general rules for designing the paths of operation of an in-car infotainment system described in this project can be applied to other domains and open perspectives for future research.

O objetivo desta dissertação é construir uma hipótese de mecanismo causal do esquerdismo nos governos de esquerda renovadora da América Latina a partir do estudo de caso do racha à esquerda do Frente Amplio (FA) do Uruguai, e testar esta hipótese com o caso do racha à esquerda do Partido dos Trabalhadores (PT) do Brasil. Utilizando theory building process-tracing, a partir da literatura sobre partidos políticos foram elaboradas, e testadas no caso uruguaio, três hipóteses de partes de mecanismo causal, as quais estabelecem: (i) o movimento ao centro feito pelo FA para atingir objetivos eleitorais é parte do mecanismo causal do racha da fração 26M; (ii) as situações de crise com o governo do Presidente Tabaré Vázquez se constituíram em parte do mecanismo causal do racha do 26M; e (iii), a diminuição das oportunidades do 26M de incidir na toma de decisões do FA, combinada com sua perda de zonas de incerteza dentro do partido, tornou- se parte do mecanismo causal do racha desta fração. As evidências apresentadas para cada hipótese suportaram o Hoop test, o que deu um alto poder confirmatório das hipóteses, porém, não permitiu descartar hipóteses alternativas. Com base nos resultados do caso Uruguaio, se construiu uma hipótese de mecanismo causal dos processos de esquerdismo nos governos de esquerda renovadora da América Latina que contém 8 partes, as entidades (atores) e ações envolvidas em cada uma delas. Por fim, utilizando theory-testing process-tracing, se fizeram apontamentos sobre o funcionamento da hipótese no caso do processo das frações que racharam com o PT e formaram o Partido Socialismo e Liberdade (PSOL). As evidências apresentadas neste caso não foram submetidas a testes empíricos, porém, de maneira geral, não diminuíram nossa confiança na hipótese de mecanismo causal. Inclusive, se produzindo uma trajetória divergente entre as frações que derivou na estruturação em dois momentos do PSOL, não foi necessário adicionar de maneira ad-hoc partes para o mecanismo, pois as foças causais foram transmitidas pelas partes nele estabelecidas, encurtando-o no caso das frações que racharam no primeiro momento, e percorrendo-o parte por parte, no caso da fração que rachou no segundo momento. / The aim of this Master\'s dissertation is to construct a causal mechanism hypothesis of leftism in the Latin American renovation of left-wing governments. This will be reviewed in two parts: starting with the case study of the split in the left of the Frente Amplio (FA) party of Uruguay, and furthermore to test the hypothesis with the case study of the split in the left of the Partido dos Trabalhadores (PT) of Brazil. Using theory- building process-tracing from literature about political parties, three hypotheses of parts of causal mechanism were elaborated and tested in the Uruguayan case, which established that: (i) the movement towards the center made by the FA to achieve electoral objectives was part of the causal mechanism of the split of the fraction 26M; (ii) crisis situations with the government of President Tabaré Vázquez were part of the causal mechanism of the split of 26M; and (iii) the reduction of 26M\'s opportunities to influence FA decision-making process, combined with the loss of zones of uncertainty within the party, became part of the causal mechanism of fracture of this fraction. The evidences presented for each hypothesis withstood the Hoop test, which gave a high confirmatory power to the hypotheses, however, they did not allow for the disregard of alternative hypotheses. Based on the results in the case of Uruguay, a hypothesis of causal mechanism of the leftist processes in the Latin American renovation of left-wing governments was constructed, which contains 8 parts, the entities (actors) and actions involved in each one of them. Finally, using theory-testing process-tracing, notes were made on the functionality of the hypothesis in the process of fractions that broke with the PT and formed the Partido Socialismo e Liberdade (PSOL). The evidence presented in this case was not subjected to empirical tests, however, in general, it did not diminish our confidence in the causal mechanism hypothesis. Even if there was a divergent trajectory between the fractions that resulted in the structuring in two moments of PSOL, it was not necessary to add parts to the mechanism ad-hoc, because the causal forces were transmitted to the parties in it, shortening it in the case of the fractions that broke initially, and going part by part, in the case of the fraction that broke after.

Mobile technology is improving in quality and capability faster now than ever before. When first introduced, cell phones were strictly used to make voice calls; now, they play satellite radio, MP3s, streaming television, have GPS and navigation capabilities, and have multi-megapixel video cameras. In the near future, cell phones will have programmable graphics processing units (GPU) that will allow users to play games similar to those currently available for top-of-the-line game consoles. Personal digital assistants enable users with full email, scheduling, and internet browsing capabilities in addition to those features offered on cell phones. Underlying all this mobile technology and entertainment is a battery whose technology has just barely tripled in the past 15 years, compared to available disk capacity that has increased over 1,000-fold. Ray tracing is a rendering technique used to generate photorealistic images that include reflections, refraction, participating media, and can fairly easily be extended to include photon mapping for indirect illumination and caustics. In recent years, ray tracing has been implemented on the GPU using various acceleration structures to facilitate rendering. Until now, all studies have used build time and achievable frame rates to determine which acceleration structure is best for ray tracing. We present the very first results comparing both CPU and GPU raytracing using various acceleration structures in terms of energy consumption. By exploring per-pixel costs, we provide insight on the energy consumption and frame rates that can be experienced on cell phones and other mobile devices based on currently available screen resolutions. Our results show that the choice in processing unit has the greatest affect on energy and time costs of ray tracing, followed by the size of the viewport used, and the choice of acceleration structure has the least impact on efficiency. For mobile devices enabled with a programmable GPU, whether it is a cell phone, PDA, or laptop computer, a bounding volume hierarchy implemented on the GPU is the most energy-efficient acceleration structure for ray tracing. Ray tracing on cellular phones with smaller screen resolutions is most energy-efficient using a CPU-based Kd-Tree implementation.

This study is a case study that observes the development of equality strategies in the European Union. After the former strategy for equality ended in 2015 there has been expectations that the European Commission would present a new strategy for equality. Therefore, the new strategy for equality was a disappointment for several actors and institutions of the European Union. The new strategy for equality is a work document and has a lower status in comparison with former strategies for equality in the EU. As a result, several actors and institutions are worried about the development of equality without a complete strategy.   To examine the development of strategies for equality in the EU historical institutionalism and a process called historic process tracing is used in this case study. The current strategy for equality 2016-2019 is going to be compared to the former strategies for 2006-2010 and 2010-2015. Are there any indications that the new work document represents a critical juncture or is it the result of path dependency and the way that EU equality strategies follows? To observe this case Hall and Taylors´ four distinct features of historical institutionalism has been the theoretical vantage point in this study.   To summarize the results of this study there has not been many substantial changes between the different equality strategies. However, changes has been identified through the way the commission presents their strategies. The new strategy for equality has also been criticised for the way the Commission has presented the document.  There are signs of a conflict in the union where different institutions rely on different patterns and structures. While the Commission presents a work document other actors and institutions in the EU are currently debating for a concise and formal strategy.

This thesis presents how performance data from hardware accelerators can be included in event logs. It extends the capabilities of trace-based performance analysis to also monitor and record data from this novel parallelization layer. The increasing awareness to power consumption of computing devices has led to an interest in hybrid computing architectures as well. High-end computers, workstations, and mobile devices start to employ hardware accelerators to offload computationally intense and parallel tasks, while at the same time retaining a highly efficient scalar compute unit for non-parallel tasks. This execution pattern is typically asynchronous so that the scalar unit can resume other work while the hardware accelerator is busy. Performance analysis tools provided by the hardware accelerator vendors cover the situation of one host using one device very well. Yet, they do not address the needs of the high performance computing community. This thesis investigates ways to extend existing methods for recording events from highly parallel applications to also cover scenarios in which hardware accelerators aid these applications. After introducing a generic approach that is suitable for any API based acceleration paradigm, the thesis derives a suggestion for a generic performance API for hardware accelerators and its implementation with NVIDIA CUPTI. In a next step the visualization of event logs containing data from execution streams on different levels of parallelism is discussed. In order to overcome the limitations of classic performance profiles and timeline displays, a graph-based visualization using Parallel Performance Flow Graphs (PPFGs) is introduced. This novel technical approach is using program states in order to display similarities and differences between the potentially very large number of event streams and, thus, enables a fast way to spot load imbalances. The thesis concludes with the in-depth analysis of a case-study of PIConGPU---a highly parallel, multi-hybrid plasma physics simulation---that benefited greatly from the developed performance analysis methods. / Diese Dissertation zeigt, wie der Ablauf von Anwendungsteilen, die auf Hardwarebeschleuniger ausgelagert wurden, als Programmspur mit aufgezeichnet werden kann. Damit wird die bekannte Technik der Leistungsanalyse von Anwendungen mittels Programmspuren so erweitert, dass auch diese neue Parallelitätsebene mit erfasst wird. Die Beschränkungen von Computersystemen bezüglich der elektrischen Leistungsaufnahme hat zu einer steigenden Anzahl von hybriden Computerarchitekturen geführt. Sowohl Hochleistungsrechner, aber auch Arbeitsplatzcomputer und mobile Endgeräte nutzen heute Hardwarebeschleuniger um rechenintensive, parallele Programmteile auszulagern und so den skalaren Hauptprozessor zu entlasten und nur für nicht parallele Programmteile zu verwenden. Dieses Ausführungsschema ist typischerweise asynchron: der Skalarprozessor kann, während der Hardwarebeschleuniger rechnet, selbst weiterarbeiten. Die Leistungsanalyse-Werkzeuge der Hersteller von Hardwarebeschleunigern decken den Standardfall (ein Host-System mit einem Hardwarebeschleuniger) sehr gut ab, scheitern aber an einer Unterstützung von hochparallelen Rechnersystemen. Die vorliegende Dissertation untersucht, in wie weit auch multi-hybride Anwendungen die Aktivität von Hardwarebeschleunigern aufzeichnen können. Dazu wird die vorhandene Methode zur Erzeugung von Programmspuren für hochparallele Anwendungen entsprechend erweitert. In dieser Untersuchung wird zuerst eine allgemeine Methodik entwickelt, mit der sich für jede API-gestützte Hardwarebeschleunigung eine Programmspur erstellen lässt. Darauf aufbauend wird eine eigene Programmierschnittstelle entwickelt, die es ermöglicht weitere leistungsrelevante Daten aufzuzeichnen. Die Umsetzung dieser Schnittstelle wird am Beispiel von NVIDIA CUPTI darstellt. Ein weiterer Teil der Arbeit beschäftigt sich mit der Darstellung von Programmspuren, welche Aufzeichnungen von den unterschiedlichen Parallelitätsebenen enthalten. Um die Einschränkungen klassischer Leistungsprofile oder Zeitachsendarstellungen zu überwinden, wird mit den parallelen Programmablaufgraphen (PPFGs) eine neue graphenbasisierte Darstellungsform eingeführt. Dieser neuartige Ansatz zeigt eine Programmspur als eine Folge von Programmzuständen mit gemeinsamen und unterchiedlichen Abläufen. So können divergierendes Programmverhalten und Lastimbalancen deutlich einfacher lokalisiert werden. Die Arbeit schließt mit der detaillierten Analyse von PIConGPU -- einer multi-hybriden Simulation aus der Plasmaphysik --, die in großem Maße von den in dieser Arbeit entwickelten Analysemöglichkeiten profiert hat.