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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Building a fire propagation system in real-time graphics / Skapande av brandspridningssystem i realtidsgrafik

Olsson, Kristian January 2017 (has links)
This report covers the creation of a dynamic fire propagation method for a real-time environment. The purpose is to see if it is possible to create a system that can control fire propagation behaviour and visual design based on some sort of simple parametrization, the purpose stems from the lack of a system to control and design a fire propagation scenario. To attain the results, a fire propagation method is devised based on the purpose of having a parameter based system, this method is created through the use of scripting in a real-time game engine to control visuals and behaviour of built in particle systems. Results show fire propagation through an example scenario where the fire behaves differently based on the material that is burning, based on parameters set by an artist. These results conclude that is it possible to create a parameter based fire propagation system and that it can be used to change the visual design and behaviour and be expanded to provide better artist input and control. The report suggests further research in the area of simplified controlled fire simulation in real-time engines, and usability. / Den här rapporten täcker skapandet av en metod för dynamisk eldspridning i en realtidsmiljö. Syftet är att se om det är möjligt att skapa ett system som kan kontrollera spridningsbeteendet och den visuella designen av elden baserat på någon sorts simplifierad parametrisering, Syftet härstammar ifrån att det saknas system där man kan kontrollera och designa ett eldspridningsscenario. För att nå resultat så skapas en metod som är baserad på syftet att använda ett parameterbaserat system, denna metoden skapas med hjälp av programmering i en realtidsmotor genom att kontrollera det visuella samt beteendet hos inbyggda partikelsystem. Resultatet visar eldspridning genom ett exempelscenario där elden beter sig olika baserat på vilket material som brinner, baserat på parametrar som är satta av en artist. Slutsatsen av resultatet visar att det är möjligt att skapa ett parameterbaserat eldspridningssystem och att det kan användas för att kontrollera den visuella designen och beteende samt att det kan expanderas för att förse artister med bättre kontroll över systemet. Rapporten föreslår fortsatta studier inom området simplifierade kontrollerade eldsimulationer inom realtidsmotorer, och användarvänlighet.
42

Behovet av indirekt eld och CAS vid militära operationer i bergsterräng / The need for indirect fire and close air support in military operations in mountainous terrain

Bragstedt, Jesper January 2010 (has links)
<p>Denna uppsats syftar till att undersöka behovet av indirekt eld och Close Air Support i militäraoperationer i bergsterräng och belysa vilka aspekter som påverkar nyttjandet av försvarsmaktensenheter och verkanssystem vid insatser i bergsmiljö. För att svara på syftet med uppsatsen har följande studiefråga ställts: Hur använde USA den grundläggande förmågan verkan för att påverka motståndaren under Operation Anaconda? Fallstudie och textanalys har använts som vetenskaplig metod och teknik för denna uppsats. Inledningsvis studerades texter om operation Anaconda och hur operationen genomfördes. Därefter studerades svenska doktriner och reglementen avseende teorier om grundläggande förmågor och hur verkan uppnås i striden. Slutligen analyserades hur USA använde den grundläggande förmåganverkan under operation Anaconda med tyngdpunkt på indirekt eld och close air support. De viktigaste slutsatserna är att striden genomförs i tre dimensioner med indirekt eld, direktriktadeld och minor. Alla är väsentliga för att effekt med verkan skall uppnås i striden. Försvinner en dimension bör de andra dimensionerna öka med fler element.</p> / <p>This paper aims to examine the need for indirect fire and Close Air Support of military operations in mountainous terrain, highlighting the aspects that affect the use of Swedish armed forces units and their technical systems in the mountain environment. To answer the purpose of this paper the following question was asked: How did U.S. forces use the basic capacity of effect to the opponent during Operation Anaconda? A case study and text analysis has been used as a scientific method and technique for this thesis. Initially texts about Operation Anaconda were studied on how the operation was carried out. Then Swedish doctrines and regulations relating to theories of basic abilities and the effect achieved in the battle were studied. Finally, the writer analyzed how the U.S. used the basic capacity of effect during Operation Anaconda, with an emphasis on indirect fire and close air support. The main conclusions are that the battle is carried out in three dimensions with indirect fire, direct fire and mines. All are essential to achieved effect in the battle. If one dimension diminishes the other dimensions should increase by more elements.</p>
43

Behovet av indirekt eld och CAS vid militära operationer i bergsterräng / The need for indirect fire and close air support in military operations in mountainous terrain

Bragstedt, Jesper January 2010 (has links)
Denna uppsats syftar till att undersöka behovet av indirekt eld och Close Air Support i militäraoperationer i bergsterräng och belysa vilka aspekter som påverkar nyttjandet av försvarsmaktensenheter och verkanssystem vid insatser i bergsmiljö. För att svara på syftet med uppsatsen har följande studiefråga ställts: Hur använde USA den grundläggande förmågan verkan för att påverka motståndaren under Operation Anaconda? Fallstudie och textanalys har använts som vetenskaplig metod och teknik för denna uppsats. Inledningsvis studerades texter om operation Anaconda och hur operationen genomfördes. Därefter studerades svenska doktriner och reglementen avseende teorier om grundläggande förmågor och hur verkan uppnås i striden. Slutligen analyserades hur USA använde den grundläggande förmåganverkan under operation Anaconda med tyngdpunkt på indirekt eld och close air support. De viktigaste slutsatserna är att striden genomförs i tre dimensioner med indirekt eld, direktriktadeld och minor. Alla är väsentliga för att effekt med verkan skall uppnås i striden. Försvinner en dimension bör de andra dimensionerna öka med fler element. / This paper aims to examine the need for indirect fire and Close Air Support of military operations in mountainous terrain, highlighting the aspects that affect the use of Swedish armed forces units and their technical systems in the mountain environment. To answer the purpose of this paper the following question was asked: How did U.S. forces use the basic capacity of effect to the opponent during Operation Anaconda? A case study and text analysis has been used as a scientific method and technique for this thesis. Initially texts about Operation Anaconda were studied on how the operation was carried out. Then Swedish doctrines and regulations relating to theories of basic abilities and the effect achieved in the battle were studied. Finally, the writer analyzed how the U.S. used the basic capacity of effect during Operation Anaconda, with an emphasis on indirect fire and close air support. The main conclusions are that the battle is carried out in three dimensions with indirect fire, direct fire and mines. All are essential to achieved effect in the battle. If one dimension diminishes the other dimensions should increase by more elements.
44

Nabíjení prachových zrn v ionizovaných prostředích / Charging of dust grains in ionized media

Vaverka, Jakub January 2014 (has links)
No description available.
45

Propriétés optiques de nanocristaux de CdSe/ZnS individuels à basse température

Biadala, Louis 30 June 2010 (has links)
Les nanocristaux de CdSe font l'objet d'applications émergentes dans les domaines de la nano-électronique, des technologies laser ou du marquage fluorescent de biomolécules. Pour ces applications, la détermination de la structure fine de l'exciton de bord de bande et des mécanismes de relaxation entre sous-niveaux est d'un intérêt majeur. Cette thèse a été consacrée à l'étude spectroscopique à basse température et sous champ magnétique de nanocristaux individuels de CdSe/ZnS. La remarquable photostabilité des nanocristaux étudiés a permis de caractériser les propriétés optiques des deux états excitoniques de plus basse énergie: l'état excitonique fondamental "noir", et l'état excitonique "brillant" situé quelques meV plus haut en énergie. Ces études ont aussi permis d'identifier un état excitonique chargé (trion) et de caractériser ses propriétés photophysiques. La possibilité de générer une cascade radiative biexciton-exciton a également été démontrée dans ces systèmes. / CdSe nanocrystals are attractive for many applications such as nanoscale electronics, laser technology, and biological fluorescent labelling. A detailed understanding of the band-edge exciton fine structure and the relaxations pathways between sub-levels are crucial for these applications. During this project we have studied the optical properties of single CdSe/ZnS nanocrystals at cryogenical temperature and under magnetic field. The dramatic photostability of the nanocrystals' emission has allowed the optical study of the two lowest exciton states: the "dark" excitonic state and the "bright" excitonic state, lying few meV above. These studies have also enabled us to identify a charged excitonic state (negative trion) and to characterize its photophysical properties. Besides we have demonstrated that in these nanocrystals, radiative cascade biexciton-exciton might be generated.
46

Fire Detection System using Infrared Sensor and Camera

Burghardt, Kristoffer, Forslund, Martin January 2022 (has links)
The last decades has seen the rise of digitization and automation of certain tasks at dangerous work environments though this has not yet affected the firefighting profession. With sensors and remote vehicles it is possible to aid the firefighters in analyzing a situation and aid them in the extinguishing efforts which reduces risks and time spent finding the fires. This thesis proposes a solution to such a problem by designing and implementing a case study. The test system was tested in a controlled environment to verify the functionality of the system. The results show that this is possible using low resolution thermal imaging equipment. The case study also shows that standard imaging equipment is a useful tool to determine the severity of the scene as well as searching for people. / Under de senaste decennierna har digitaliseringen och automatisering av uppgifter i farliga arbetsmiljöer ökat, detta har inte ännu påverkat brandkåren. Med hjälp av sensorer och fjärrstyrda fordon kan detta göra det möjligt att hjälpa brandmän att analysera en situation och hjälpa till med brandsläckning vilket reducerar riskerna och tid att hitta bränder. Denna avhandling framför en lösning till ett sådant problem genom att skapa och implementera en fallstudie. Testsystemet var testat i en kontrollerad miljö att verifiera funktionaliteten av systemet. Resultaten visar att det är möjligt att använda sig av en lågupplöst värmekamera. Fallstudien visade även att bildutrustning är ett användbart verktyg för att bestämma allvarlighetsgraden av miljön och för att söka efter människor.
47

Emotion in video game audio : Can sound effects be perceived to contain positive emotional content?

Bélteky, Markus January 2019 (has links)
Sound is an important part of almost all media. In games, sounds are used to evoke intense emotions in players. Studies has showed that music on its own can induce emotions. Soundeffects is another type of sounds that appear in games. However, do they contribute to the emotional experience? Understanding this will help sound designers enhance scenes in future video games. In this study, 23 participants were asked to conduct a test divided into two part. In the first part they were tasked to listen to four sound effects of fire and choose attributes from a predetermined list that they thought suited. Among these physical attributes were two emotional attributes. In the second part, the subjects were tasked with choosing one of the fours sound effects for a scenario with a positive emotion and motivate their choice. The results show that no sound had neither positive nor negative as an emotional attribute. Of the four sounds, two showed significance that emotion alone was an attribute for the sound. The results from the second part showed that the subjects were divided in what motivated them to choose a sound. More than a third of the subjects based their choice only on if the sound matched the emotion of the scenario presented while slightly less than a third based it only on to fit the location. The last third based it on both emotion and location.
48

A search for pulsating B-type variable stars in the southern open clusters NGC 6204 and Hogg 22 / Jacobus Johannes (Jaco) Mentz

Mentz, Jacobus Johannes January 2013 (has links)
The theory of stellar evolution and stellar structure relies on the observation of stars in di erent phases of their evolutionary cycle. The relation between observations and theory can be strengthened by obtaining observational data of a large sample of stars in a particular evolutionary phase. The search for Cephei stars, as conducted in this study, can contribute to the sample of known Cephei stars, where these interesting stars are massive non-supergiant early B-type stars, displaying pulsating behaviour which is not well understood. Stars tend to form in clusters where it can therefore be expected that young massive stars can be found in open clusters. For this reason two young southern open clusters were observed in order to search for B-type pulsating stars. The region of NGC 6204 and Hogg 22 was observed over a period of thirteen nights in Johnson B, V and I bands. NGC 6204 is believed to be the oldest cluster of the two at a distance of 0.8 kpc while the much younger Hogg 22 is more distant at 2.8 kpc. These two open clusters are located 6 arcminutes apart which made it possible to observe them simultaneously with a 12.8 12.8 arcminute eld of view. The observations were done with the newly installed 1600 telescope of the North-West University, South Africa. In order to do a variability search, periodic stars need to be identi ed from the cluster data, where a typical data set may contain thousands of scienti c images. In addition to the main motivation for this study, a pipeline was created in order to automate the photometry and data reduction processes. A Lomb-Scargle transform was applied to the stellar light curves in order to identify periodic sources. 354 signi cantly periodic stars were identi ed from the 3182 observed stars. Amongst them, two new possible Cephei stars were found together with a possible slowly pulsating B star (SPB), and numerous eclipsing binary systems. By using photometry of this region obtained by Forbes & Short (1996), instrumental magnitudes were transformed to a standard system in order to compare photometry results. From the constructed colour magnitude diagram of the two clusters, it could be seen that some stars, indicated by Forbes & Short (1996) to be cluster members, were in fact eld stars belonging to neither cluster. The reduction and photometry pipeline was implemented successfully on the data set, which also highlighted the importance of instrumentation and correct data analysis procedures. Possible improvements were identi ed in order to overcome di culties experienced during this study. / Thesis (MSc (Space Physics))--North-West University, Potchefstroom Campus, 2013
49

A search for pulsating B-type variable stars in the southern open clusters NGC 6204 and Hogg 22 / Jacobus Johannes (Jaco) Mentz

Mentz, Jacobus Johannes January 2013 (has links)
The theory of stellar evolution and stellar structure relies on the observation of stars in di erent phases of their evolutionary cycle. The relation between observations and theory can be strengthened by obtaining observational data of a large sample of stars in a particular evolutionary phase. The search for Cephei stars, as conducted in this study, can contribute to the sample of known Cephei stars, where these interesting stars are massive non-supergiant early B-type stars, displaying pulsating behaviour which is not well understood. Stars tend to form in clusters where it can therefore be expected that young massive stars can be found in open clusters. For this reason two young southern open clusters were observed in order to search for B-type pulsating stars. The region of NGC 6204 and Hogg 22 was observed over a period of thirteen nights in Johnson B, V and I bands. NGC 6204 is believed to be the oldest cluster of the two at a distance of 0.8 kpc while the much younger Hogg 22 is more distant at 2.8 kpc. These two open clusters are located 6 arcminutes apart which made it possible to observe them simultaneously with a 12.8 12.8 arcminute eld of view. The observations were done with the newly installed 1600 telescope of the North-West University, South Africa. In order to do a variability search, periodic stars need to be identi ed from the cluster data, where a typical data set may contain thousands of scienti c images. In addition to the main motivation for this study, a pipeline was created in order to automate the photometry and data reduction processes. A Lomb-Scargle transform was applied to the stellar light curves in order to identify periodic sources. 354 signi cantly periodic stars were identi ed from the 3182 observed stars. Amongst them, two new possible Cephei stars were found together with a possible slowly pulsating B star (SPB), and numerous eclipsing binary systems. By using photometry of this region obtained by Forbes & Short (1996), instrumental magnitudes were transformed to a standard system in order to compare photometry results. From the constructed colour magnitude diagram of the two clusters, it could be seen that some stars, indicated by Forbes & Short (1996) to be cluster members, were in fact eld stars belonging to neither cluster. The reduction and photometry pipeline was implemented successfully on the data set, which also highlighted the importance of instrumentation and correct data analysis procedures. Possible improvements were identi ed in order to overcome di culties experienced during this study. / Thesis (MSc (Space Physics))--North-West University, Potchefstroom Campus, 2013
50

Newton's methods under the majorant principle on Riemannian manifolds / Métodos de Newton sob o princípio majorante em variedades riemannianas

Martins, Tiberio Bittencourt de Oliveira 26 June 2015 (has links)
Submitted by Cláudia Bueno (claudiamoura18@gmail.com) on 2015-10-29T19:04:41Z No. of bitstreams: 2 Tese - Tiberio Bittencourt de Oliveira Martins.pdf: 1155588 bytes, checksum: add1eac74c4397efc29678341b834448 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2015-11-03T14:25:04Z (GMT) No. of bitstreams: 2 Tese - Tiberio Bittencourt de Oliveira Martins.pdf: 1155588 bytes, checksum: add1eac74c4397efc29678341b834448 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2015-11-03T14:25:04Z (GMT). No. of bitstreams: 2 Tese - Tiberio Bittencourt de Oliveira Martins.pdf: 1155588 bytes, checksum: add1eac74c4397efc29678341b834448 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2015-06-26 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Apresentamos, nesta tese, uma an álise da convergência do m étodo de Newton inexato com tolerância de erro residual relativa e uma an alise semi-local de m etodos de Newton robustos exato e inexato, objetivando encontrar uma singularidade de um campo de vetores diferenci avel de nido em uma variedade Riemanniana completa, baseados no princ pio majorante a m invariante. Sob hip oteses locais e considerando uma fun ção majorante geral, a Q-convergância linear do m etodo de Newton inexato com uma tolerância de erro residual relativa xa e provada. Na ausência dos erros, a an alise apresentada reobtem o teorema local cl assico sobre o m etodo de Newton no contexto Riemanniano. Na an alise semi-local dos m etodos exato e inexato de Newton apresentada, a cl assica condi ção de Lipschitz tamb em e relaxada usando uma fun ção majorante geral, permitindo estabelecer existência e unicidade local da solu ção, uni cando previamente resultados pertencentes ao m etodo de Newton. A an alise enfatiza a robustez, a saber, e dada uma bola prescrita em torno do ponto inicial que satifaz as hip oteses de Kantorovich, garantindo a convergência do m etodo para qualquer ponto inicial nesta bola. Al em disso, limitantes que dependem da função majorante para a taxa de convergência Q-quadr atica do m étodo exato e para a taxa de convergência Q-linear para o m etodo inexato são obtidos. / A local convergence analysis with relative residual error tolerance of inexact Newton method and a semi-local analysis of a robust exact and inexact Newton methods are presented in this thesis, objecting to nd a singularity of a di erentiable vector eld de ned on a complete Riemannian manifold, based on a ne invariant majorant principle. Considering local assumptions and a general majorant function, the Q-linear convergence of inexact Newton method with a xed relative residual error tolerance is proved. In the absence of errors, the analysis presented retrieves the classical local theorem on Newton's method in Riemannian context. In the semi-local analysis of exact and inexact Newton methods presented, the classical Lipschitz condition is also relaxed by using a general majorant function, allowing to establish the existence and also local uniqueness of the solution, unifying previous results pertaining Newton's method. The analysis emphasizes robustness, being more speci c, is given a prescribed ball around the point satisfying Kantorovich's assumptions, ensuring convergence of the method for any starting point in this ball. Furthermore, the bounds depending on the majorant function for Q-quadratic convergence rate of the exact method and Q-linear convergence rate of the inexact method are obtained.

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