The Koulekoun Gold project is the most important prospect of Avocet Mining plc. It is one of the projects within the TriK-block in Guinea (West Africa) for which an exploration permit has been granted. The Koulekoun deposit is located within the Siguiri basin of Birimian age in the Eastern Guinea region; where most Guinea’s gold mines are situated. The present study involves the investigation of structural elements (S₀, S₁, S₂, intrusive contacts, faults and veins) from selected drill cores from drill sections that intersect the Koulekoun orebody in four parts of the deposit; characterizes the principal orientations of measured structures and determines their relationships using stereonet; in order to predict important intersections to focus on in exploration programs within the TriK-block and suggests a possible structural model of the Koulekoun deposit. Raw data used for the present research was collected from half-core samples due to the absence of surface outcrop from which direct measurements could have been made. Measured data were interpreted using stereographic projection. Often no preferred orientations of structural elements exist in the area, suggesting a complex structural situation, particularly with regard to hydrothermal vein attitudes. Thus, it has been illustrated from structural data analysis and S₀ data 3d interpolation of the four sub-structural domains (North-East, North-West, Central and South) that NE-SW structures (S₂, intrusive contact, fault and vein) have controlled the occurrency of gold mineralization in the Koulekoun deposit area. Geometrical relationships between structure main cluster orientation from stereonet analysis show the majority of S₀ moderately E-dipping; intrusive contacts dip at moderate angle to the SE in all zones, except in the North-East zone where they are sub-vertical and SE-dipping. Fault planes show variable orientation of NE-SW, NW-SE and E-W, and steeply SE-dipping. Vein planes correspond to fault systems and show high variability in their orientation with numerous orders of vein direction in each domain. The cross-cutting relationships suggest two principal generations of faults: the NE-SW fault (F1) and the NW-SE fault (F2). These two fault systems and their associated vein intersection areas preferably define the ore shoot zones within the Koulekoun deposit. The proposed structural model of the Koulekoun deposit suggests the intersection and interference of major NW-SE and minor NE-SW structures. The interference of folds formed basin-dome structures with oval shape geometries striking NW-SE and that dominantly occur in North-East, North-West and Central zones. The South Zone is characterized by NE-SW gently plunging and moderately inclined folds with NW-SE striking axial surface. Gold mineralization occurs at the edges of basin-dome structures in North-East, North-West and Central zones. Mineralized porphyry intrusions are likely located within the axial surface of the South zone folds and extend toward the Central zone. The proposed model is compliant with the earlier model of the Koulekoun deposit presented by Tenova (2013); Fahey et al. (2013) describing the Koulekoun deposit as an auriferous NE-SW trending fault zone, intersecting a major NW-striking and steeply E-dipping porphyry units. The model also fits within the regional structural context suggested by Lahondere et al. (1999a) related to the E-W vein structures attributed to NW-SE fractures and to the conjugated fault of NE-SW direction. Comparatively to the three industrial gold deposits (Siguiri, Lero, Kiniero) being currently mined in the Siguiri Basin, and defined as mesothermal vein and lode mineralization hosted in Birimian meta-sedimentary rocks (Lalande, 2005), the Koulekoun gold deposit appears to be a porphyry hosted orogenic disseminated style mineralization system (Fahey et al., 2013). Although, similarities between the Koulekoun gold deposit and these three industrial deposits (Siguiri, Lero, Kiniero) constitute of the intensive extends of the weathering profile and at some stages, by the existence of numerous ring-shaped and curved lineaments enhanced by drag folding (Lero deposit for instance). It is therefore recommended that targets selection around the Koulekoun deposit and within the TriK-block for further exploration programs be concentrated along NW-SE structures, in objective to determine possible intersection zones with NE-SW structures.

Le schéma d'allumage par choc pour la fusion par confinement inertiel utilise une impulsion laser intense à la fin d'une phase d'assemblage de combustible. Les paramètres clefs de ce schéma sont la génération d'une haute pression d'ablation, l'amplification de la pression du choc généré par un facteur supérieur à cent et le couplage du choc avec le point chaud de la cible. Dans cette thèse, de nouveaux modèles semi-analytiques sont développés afin de décrire le choc d'allumage depuis sa génération jusqu'à l'allumage du combustible. Tout d'abord, un choc sphérique convergent dans le coeur pré-chauffé de la cible est décrit. Le modèle est obtenu par perturbation de la solution auto-semblable de Guderley en tenant compte du nombre de Mach du choc élevé mais fini. La correction d'ordre un tient compte de l'effet de la force du choc. Un critère d'allumage analytique est exprimé en fonction de la densité surfacique du point chaud et de la pression du choc d'allumage. Le seuil d'allumage est plus élevé pour un nombre de Mach faible. Il est montré que la pression minimale du choc, lorsqu'il entre dans le coeur de la cible, est de 20Gbar. La dynamique du choc dans la coquille en implosion est ensuite analysée. Le choc se propage dans un milieu non inertiel avec un fort gradient de pression et une augmentation temporelle générale de la pression. La pression du choc est amplifiée plus encore durant la collision avec une onde de choc divergente provenant de la phase d'assemblage. Les modèles analytiques développés permettent une description de la pression et de la force du choc dans une simulation typique de l'allumage par choc. Il est démontré que, dans le cas d'une cible HiPER, une pression initiale du choc de l'ordre de 300 Mbar dans la zone d'ablation est nécessaire. Il est proposé une analyse des expériences sur la génération de chocs forts avec l'installation laser OMEGA. Il est montré qu'une pression du choc proche de 300Mbar est atteinte près de la zone d'ablation avec une intensité laser absorbée de l'ordre de 2 X 10(15) W.cm-2 et une longueur d'onde de 351 nm. Cette valeur de la pression est deux fois plus importante que la valeur attendue en considérant une absorption collisionnelle de l'énergie laser. Cette importante différence est expliquée par la contribution d'électrons supra-thermiques générés durant l'interaction laser/plasma dans la couronne. Les modèles analytiques proposés permettent une optimisation de l'allumage par choc lorsque les paramètres de la phase d'assemblage, sont pris en compte. Les diverses approches analytiques, numériques et expérimentales sont cohérentes entre-elles. / The shock ignition concept in inertial confinement fusion uses an intense power spike at the end of an assembly laser pulse. the key feature of shock ignition are the generation of a high ablation pressure, the shock pressure amplification by at least a factor of a hundred in the cold fuel shell and the shock coupling to the hot-spot. in this theses, new semi-analytical hydrodynamic models are developed to describe the ignitor shock from its generation up to the moment of fuel ignition. A model is developed to describe a spherical concerging shock wave in a pre-heated hotspot. The self-similar solution developed by Guderley is perturbed over the shock Mach number Ms >>1. The first order correction accounts for the effects of the shock strength. An analytical ignition criterion is defined in terms of the shock strength ans th hot-spot areal density. The ignition threshold is higher when the initial Mach number of the shock is lower. A minimal shock pressure of 20 Gbar is needed when it enters the hot-spot. The shock dynamics in the imploding shell is the analyzed. The shock is propagating into a non inertial medium with a high radial pressure gradient and an averall pressure increase with time. The collision with a returning shock coming from the assembly phase enhances further the ignitor shock pressure. The analytica theory allows to des cribe the shock pressure and strength evolution in a typical shock ignition implosion. It is demonstrated that, in the case of the HiPER target design, a generation shock pressure near the ablation zone on the order of 300-400 Mbar is needed. An analysis of experiments on the strong shock generation performed on the OMEGA laser facility is presented. It is sown that a shock presssure close to 300 Mbar near the ablation zone has been reached with an absorbed laser intensity up to 2 x 10(15) W:cm-2 and a laser wavelength of 351 nm. This value is two times higher than the one expected from collisional laser absorption only. That significant pressure enhancement is explained by contribution of hot-electrons generated by non-linear laser/plasma interaction in the corona. The proposed analytical models allow to optimize the shock ignition scheme, including the inuence of the implosion parameters. Analytical, numerical and experimental results are mutualy consistent.

La synthèse d’images réalistes repose sur des modèles physiques décrivant les interactions entre la lumière et les matériaux attachés aux objets dans une scène tridimensionnelle. Ces modèles mathématiques sont complexes et, dans le cas général, n’admettent pas de solution analytique. Pour cette raison, l’utilisation de méthodes numériques robustes et efficaces est nécessaire. Les méthodes de Monte Carlo ou techniques alternatives comme l’utilisation de développement par fonction de base sont appropriées pour résoudre ce type de problème. Dans cette thèse par articles, nous présentons deux nouvelles techniques permettant l’in- tégration numérique efficace de matériaux complexes. En premier lieu, nous introduisons une nouvelle méthode permettant d’intégrer simultanément plusieurs dimensions définies dans le domaine angulaire et spatiale. Avoir une technique efficace est essentiel pour intégrer des matériaux avec des normales variant rapidement sous différentes conditions d’éclairage. Notre technique utilise une nouvelle formulation basée sur un histogramme sphérique définie de façon directionnelle et spatial. Ce dernier nous permet d’utiliser des harmoniques sphé- riques pour intégrer les différentes dimensions rapidement, réduisant le temps de calcul d’un facteur approximatif de 30× par rapport aux méthodes de l’état de l’art. Dans notre second travail, nous introduisons une nouvelle stratégie d’échantillonnage pour estimer le transport de lumière à l’intérieur de matériaux multicouches. En identifiant les meilleures stratégies d’échantillonnage, nous proposons une technique efficace et non biaisée pour construire des chemins de lumière à l’intérieur de ce type de matériau. Notre nouvelle approche permet d’obtenir un estimateur de Monte Carlo efficace et de faible variance dans des matériaux contenant un nombre arbitraire de couches. / Realistic computer generated images and simulations require physically-based models to properly capture and reproduce light-material interactions. The underlying mathematical formulations are complex and mandate the use of efficient numerical methods, since analytic solutions are not available. Monte Carlo integration is one such commonly used numerical method, although, alternative approaches leveraging, e.g., basis expansions, may be suitable to solve these challenging problems. In this thesis by articles, we present two works where we efficiently devise numerical integration strategies for the rendering of complex materials. First, we propose a method to compute a spatial-angular multi-dimensional integration problem present when rendering materials with high-frequency normal variation under large, angularly varying illumination. By computing and manipulating a novel spherical histogram data representation, we are able to use spherical harmonics to efficiently solve the integral, outperforming the state-of-the-art by a factor of roughly 30×. Our second work describes a high-performance Monte Carlo integration strategy for rendering layered materials. By identifying the best path sampling strategies in the micro-scale light transport context, we are able to tailor an unbiased and efficient path construction method to evaluate high throughput, low variance paths through an arbitrary number of layers.

L'analyse des propriétés statistiques de la distribution de la matière dans le cosmos (Grandes Structures, LSS or Large Scale Structure) est l'une des principales sondes cosmologiques qui permettent l'étude du modèle standard cosmologique, en particulier les paramètres caractérisant la matière noire et l'énergie noire. Les Oscillations Acoustiques Baryoniques (BAO's) sont l'une des mesures qui peuvent être extraites de l'étude de la distribution de matière à grande échelle (LSS).L'observation de la distribution cosmique de la matière à partir de l'émission à 21 cm de l'hydrogène atomique neutre (HI) est une nouvelle méthode, complémentaire des relevés optiques pour cartographier la distribution de la matière dans le cosmos. La méthode de cartographie d'intensité (Intensity Mapping) a été proposée depuis moins d'une dizaine d'années comme une méthode efficace pour cartographier en trois dimensions l'émission radio à 21 cm. Elle n'implique en particulier pas la détection des objets individuels (galaxies), et peut donc être effectué avec des instruments plus modestes en taille que ceux comme SKA ou FAST qui sont conçus pour détecter les galaxies à 21 cm à des distances cosmologiques. Des interféromètres radio utilisant un ensemble de réflecteurs cylindriques ou paraboliques fixes, observant le ciel en mode transit sont adaptés à la cartographie d'intensité. Le mode d'observation spécifique de ce type de radio télescope en cartographie d'intensité est étudié dans le cadre de ce travail de thèse. On montre en particulier qu'une méthode spécifique de reconstruction des cartes du ciel à partir des visibilités peut être appliquée aux observations de ces interféromètres fonctionnant en mode transit. Cette méthode correspond à la décomposition en modes m des harmoniques sphériques et est très performante pour la reconstruction de grandes zones du ciel observées en mode transit. Un code de reconstruction fondé sur ce principe a été développé, ainsi que différents critères de comparaison des performances instrumentales, comme le lobe d'antenne synthétisé, le spectre de bruit sur les cartes reconstruites et la réponse globale de l'instrument dans le plan (l,m) des harmoniques sphériques. La méthode a été appliquée à différentes configurations des interféromètres composés de réflecteurs paraboliques ou cylindriques dans le cadre des projets PAON-4 et Tianlai. Outre l'optimisation des configurations des interféromètres Tianlai et PAON-4, le travail présenté inclut une première application de la méthode aux données PAON-4. / The analysis of the statistical properties of the distribution of matter in the cosmos (LSS or Large Scale Structure) is one of the main cosmological probes that allow the study of the cosmological standard model, in particular the parameters characterizing dark matter and dark energy. Baryonic Acoustic Oscillations (BAO's) are one of the measurements that can be extracted from the study of matter distribution in large-scale structure (LSS).The observation of the cosmic distribution of the matter from neutral atomic hydrogen (HI) 21 cm emission is a new method, complementary to the optical observation to map the distribution of matter in the cosmos. In the last decade, the Intensity Mapping method has been proposed as an effective method for mapping the 21cm radio emission in three dimensions. In particular, it does not require the detection of individual objects (galaxies), and can therefore be performed with instruments smaller in size than those such as SKA or FAST, which are designed to detect 21 cm galaxies at cosmological distances. A radio interferometer using a set of fixed cylindrical or parabolic reflectors observing the sky in transit mode are suitable instruments for intensity mapping surveys. The specific observational mode from this type of radio telescope by intensity mapping is studied in the context of this thesis. We show in particular that a specific sky maps reconstruction method from the visibilities can be applied to the observations of these interferometers operating in transit mode. This method corresponds to the m-modes decomposition of the spherical harmonics and is very efficient for the reconstruction of large sky areas observed in transit mode. A reconstruction code based on this principle has been developed, as well as different criteria for the comparison of instrumental performances, such as the synthesized antenna lobe, the noise spectrum of the reconstructed maps and the overall instrument response in the spherical harmonics (l,m) plane. The method has then been applied to different configurations of interferometers composed of parabolic or cylindrical reflectors in the PAON-4 and Tianlai projects. In addition to optimizing the Tianlai and PAON-4 interferometer configurations, the work presented here includes a first application of the method to the PAON-4 data.

The diploma thesis is divided into five chapters. The first chapter is devoted to the history and usage of pendulums with focus on the development of measurement of time and gravitational acceleration. The second chapter deals with the concept of pendulum from a theoretical perspective at all levels of the Czech educational system, including a research in textbooks, collection of questions and problems, and scientific articles. In the third chapter, the results of the research of sources of inspiration for simple real- life experiments, applets and simulations, and laboratory work are presented. The fourth chapter is focused on the theoretical background of the four selected models of pendulums, and the last chapter is devoted to simple experiments with these selected models. For each experiment, a videorecording is available on the enclosed DVD. This thesis is suitable for all physics teachers, as well as for students of teaching physics. However, it may also serve as a motivation for students in optional courses of high school physics. 1

Současný vývoj v oblasti nízkovoltové elektronové mikrokospie vede ke zlepšování prostorového rozlišení cestou korekce elektronově-optických vad. V posledních letech se implementace korektorů u konvenčních elektronových mikroskopů (50-200 kV) stává standardem. Nicméně zabudování korektoru do malého stolního prozařovacího mikroskopu pracujícího s nízkým urychlovacím napětím je stále výzva. Velmi vhodným řešením korekce otvorové vady u takovýchto přístrojů se zdá být koncept hexapólového korektoru založeného na bázi permantních magnetů umožňující zachovat minimální rozměry stolního transmisního mikroskopu. Přednosti a potenciál Roseho hexapólového korektoru vzhledem k použití v nízkovoltových systémech jsou předmětem kritické analýzy obsažené v této práci, včetně zásadního příspěvku tohoto korektoru k celkové chromatické vadě přístroje. Chromatická vada zůstává, navzdory veškeré snaze o její minimalizaci, zcela zásadním aspektem při návrhu korektoru. Koncept představený v rámci této dizertační práce je určen především pro skenovací prozařovací transmisní mód z důvodu omezení nárůstu chromatické vady způsobeného průchodem elektronového svazku preparátem. V práci lze také nalézt podrobný popis navržených kompenzačních systémů korektoru určených k precisnímu seřízení optické soustavy.

The diploma thesis deals with selected fracture tests and evaluation of fracture parameters of cement-based composite. One part of the thesis deals with cement-based composite with glass spherical aggregate of a single fraction of 2 mm. After production, the beams with dimensions of 20×40×200mm exposed to temperatures in the range from 100 to 1000 °C for one hour. Using the non-destructive ultrasonic pulse method, the degree of damage caused by termal load was determined. Selected specimen with central edge notch were then tested in three-point bending and fragments after these tests were tested in compression. In the second part, attention was paid to the evaluation of fracture tests conducted on specimen from drill-cores taken from selected objects located at the former Transgas Gas Control Center in Prague. The specimen were provided with a chevron notch before being tested in three-point bending. The measured data was modified by the GTDiPS program and in the case of the glass composite the StiCrack program was used to evaluate fracture parameters.

This diploma thesis is focused on the surface hardening of cast irons with spheroidal graphite. The work describes a theoretical analysis of the structure and properties of cast irons and individual methods suitable for surface hardening. The practical part describes the production of cast iron castings with spheroidal graphite, on which the surface hardening is performed, tensile test, hardening of produced castings by induction and laser surface hardening, preparation of samples for measuring microhardness and metallographic analysis of metal structures.

The thesis deals with the pouring of epoxy materials over LED strips. The research part contains an introduction to photometry and summarizes the types of potting compounds along with their characteristics. The practical part delves into the effect different amount of pigment has on the photometric properties. This is assessed based on verified measurements performed with the help of a goniophotometer on samples with different amounts of pigment, which were created using an integration sphere. Furthermore, a brightness analysis and a long-term outdoor test were performed.

Master's thesis includes designing of exhibition pavilon on a circular platform with a diameter of 35m. The pavilon is designed as a schwedler circular dome. The construction is designed as a ball and is made of tubes. Pavilon includes designing of floors and stairs bearing system that is also made of steel.