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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.
151

Automobilová on-board kamera se záznamem telemetrie / Car On-Board Videocamera with Telemetry Recording

Špaňhel, Petr January 2012 (has links)
This master thesis deals with the design devices for automobile driving record with the information on telemetry. Camera placed in the vehicle captures the traffic before the accident, can facilitate the decisions about the offender. The basic element of the camera is DaVinci development kit has been developed for digital video applications. The aim of this thesis is to find ways to effectively implement basic algorithms for processing and evaluation of the scanned image using a single-chip microprocessor.
152

Obrazové detektory rentgenového záření pro aplikace v microCT systémech / X-ray Image detectors for using in microCT systems.

Papajová, Gabriela January 2017 (has links)
Diplomová práce se zabývá detektory rentgenového záření pro mikro-CT systémy. Teoretická část zahrnuje standartní typy rentgenových detektorů a požadavky na kvalitu obrazu pro výslednou 3D rekonstrukci. V závěru jsou popsány fyzikální parametry reálných detektorů a metody jejich měření a vyhodnocení.
153

Simulation of Optical Aberrations for Comet Interceptor’s OPIC Instrument

Bührer, Maximilian January 2020 (has links)
In space exploration optical imaging is one of the key measurements conducted, with a vast majority of missions heavily relying on optical data acquisition to examine alien worlds. One such endeavor is ESA’s F-class mission Comet Interceptor, a multi-element spacecraft expected to be launched in 2028. It consists of a primary platform and two sub-spacecraft, one of which carrying the Optical Periscopic Imager for Comets (OPIC). An accurate prediction of the generated imagery is of undeniable importance as mission planning and instrument design strongly depend on the real-world output quality of the camera system. In the case of OPIC, the collected image data will be used to reconstruct three dimensional models of targeted celestial bodies. Furthermore, the sub-spacecraft faces a risk of high velocity dust impacts, leading to a limited number of data samples to be broadcasted back to the primary spacecraft before collision. Testing image prioritization algorithms and reconstruction methods prior to mission start requires accurate computer-generated images. Camera sensors and lens systems are subjected to various optical distortions and aberrations that degrade the final image. Popular render engines model those effects to a certain degree only and as a result produce content that is looking too perfect. While more sophisticated software products exist, they often come with compatibility limitations and other drawbacks. This report discusses the most important optical aberrations, as well as their relevance for optical instruments in space applications with a particular focus on the Comet Interceptor mission. The main part of this work is however the implementation of a dedicated software tool that simulates a variety of optical aberrations complementing the basic camera model of the Blender render engine. While its functionality is mostly demonstrated for OPIC, the software is designed with a broad range of usage scenarios in mind.
154

Adaptive Radar with Application to Joint Communication and Synthetic Aperture Radar (CoSAR)

Rossler, Carl W., Jr 08 August 2013 (has links)
No description available.
155

Multi-Aperture Coherent Change Detection and Interferometry for Synthetic Aperture Radar

Madsen, David D. 09 March 2010 (has links) (PDF)
Interferometry and coherent change detection (CCD) utilize phase differences between complex SAR images to find terrain height and to detect small changes between images, respectively. A new method for improving interferometry and CCD using multiple sub-apertures is proposed. Using backprojection processing, multiple sub-aperture images are created for a pair of flights. An interferogram and coherence map is made from each sub-aperture. For CCD, each sub-aperture coherence map offers an independent estimate of the coherence over the same area. By combining coherence maps, low coherence areas associated with residual motion errors are reduced, shadowed areas are minimized, and the overall coherence of stationary objects between images is increased. For interferometry, combining independent estimates of a scene's height offers a more accurate height estimate. For repeat-pass interferometry, multiple apertures are shown to increase the coverage of valid height estimates. The benefits of multi-aperture interferometry and CCD are shown using examples with real data.
156

Observations de pulsateurs compacts à l'aide de la caméra Mont4K CCD

Francoeur, Myriam 12 1900 (has links)
Les pulsateurs compacts sont des étoiles présentant des variations intrinsèques de luminosité dont les gravités de surface sont supérieures à 100,000 cm/s² On retrouve parmi ces objets deux familles des sous-naines chaudes de type B (sdB) pulsantes et quatre familles distinctes de naines blanches pulsantes. Dans le but d'observer les pulsations de tels objets pour ensuite analyser leur propriétés grâce à l'astéroséismologie, l'Université de Montréal, en collaboration avec le Imaging Technology Laboratory (ITL - University of Arizona), a développé la caméra Mont4K (Montreal4K) CCD qui est, depuis le printemps 2007, le principal détecteur employé au télescope Kuiper de 1.55 m du Mt Bigelow (Steward Observatory, University of Arizona). à l'aide de ce montage, des observations ont été menées pour quelques-uns de ces pulsateurs compacts. La première cible fut HS 0702+6043, un pulsateur hybride. Une importante mission pour cet objet, réalisée du 1er novembre 2007 au 14 mars 2008, a permis d'identifier 28 modes de pulsations pour cet objet en plus de mettre en évidence pour certains de ces modes d'importantes variations d'amplitude. Deux autres cibles furent les naines blanches pulsantes au carbone de type « Hot DQ » SDSS J220029.08-074121.5 et SDSS J234843.30-094245.3. Il fut possible de montrer de façon indirecte la présence d'un fort champ magnétique à la surface de J220029.08-074121.5 grâce à la présence de la première harmonique du mode principal. En outre, pour ces deux cibles, on a pu conclure que celles-ci font bel et bien partie de la classe des naines blanches pulsantes au carbone. / Compact pulsators are stars with surface gravities larger than 100,000 cm/s² showing intrisinc luminosity variations. Six different classes of such objects are known, including two pulsating hot subdwarf (sdB), and four pulsating white dwarf classes. In order to observe their pulsations and further analyze their properties through asteroseismology, the Universit\'e de Montr\'eal, in collaboration with the University of Arizona Imaging Instrument Laboratory, developed the Mont4K (Montreal4K) CCD camera which is the primary science detector of the Kuiper 1.55 m telescope at Mt Bigelow since Spring 2007. With this setup, several compact pulsators were targeted. The first target was the hybrid pulsator HS 0702+6043, observed from November 1st 2007 to March 14th 2008, for which 28 pulsation modes were isolated. Moreover, it was possible to highlight important amplitude variations in some of these modes. Two Hot DQ white dwarf pulsators, SDSS J220029.08-074121.5 and SDSS J234843.30-094245.3, were also targeted. In the case of J220029.08-074121.5, it was possible to highlight the presence of a strong magnetic field at its surface through the presence of the first harmonic of the main pulsation mode of this object. Furthermore, the follow-up campaigns on J220029.08-074121.5 and J234843.30-094245.3 allowed to classify these two white dwarf as Hot DQ pulsators.
157

Observations de pulsateurs compacts à l'aide de la caméra Mont4K CCD

Francoeur, Myriam 12 1900 (has links)
Les pulsateurs compacts sont des étoiles présentant des variations intrinsèques de luminosité dont les gravités de surface sont supérieures à 100,000 cm/s² On retrouve parmi ces objets deux familles des sous-naines chaudes de type B (sdB) pulsantes et quatre familles distinctes de naines blanches pulsantes. Dans le but d'observer les pulsations de tels objets pour ensuite analyser leur propriétés grâce à l'astéroséismologie, l'Université de Montréal, en collaboration avec le Imaging Technology Laboratory (ITL - University of Arizona), a développé la caméra Mont4K (Montreal4K) CCD qui est, depuis le printemps 2007, le principal détecteur employé au télescope Kuiper de 1.55 m du Mt Bigelow (Steward Observatory, University of Arizona). à l'aide de ce montage, des observations ont été menées pour quelques-uns de ces pulsateurs compacts. La première cible fut HS 0702+6043, un pulsateur hybride. Une importante mission pour cet objet, réalisée du 1er novembre 2007 au 14 mars 2008, a permis d'identifier 28 modes de pulsations pour cet objet en plus de mettre en évidence pour certains de ces modes d'importantes variations d'amplitude. Deux autres cibles furent les naines blanches pulsantes au carbone de type « Hot DQ » SDSS J220029.08-074121.5 et SDSS J234843.30-094245.3. Il fut possible de montrer de façon indirecte la présence d'un fort champ magnétique à la surface de J220029.08-074121.5 grâce à la présence de la première harmonique du mode principal. En outre, pour ces deux cibles, on a pu conclure que celles-ci font bel et bien partie de la classe des naines blanches pulsantes au carbone. / Compact pulsators are stars with surface gravities larger than 100,000 cm/s² showing intrisinc luminosity variations. Six different classes of such objects are known, including two pulsating hot subdwarf (sdB), and four pulsating white dwarf classes. In order to observe their pulsations and further analyze their properties through asteroseismology, the Universit\'e de Montr\'eal, in collaboration with the University of Arizona Imaging Instrument Laboratory, developed the Mont4K (Montreal4K) CCD camera which is the primary science detector of the Kuiper 1.55 m telescope at Mt Bigelow since Spring 2007. With this setup, several compact pulsators were targeted. The first target was the hybrid pulsator HS 0702+6043, observed from November 1st 2007 to March 14th 2008, for which 28 pulsation modes were isolated. Moreover, it was possible to highlight important amplitude variations in some of these modes. Two Hot DQ white dwarf pulsators, SDSS J220029.08-074121.5 and SDSS J234843.30-094245.3, were also targeted. In the case of J220029.08-074121.5, it was possible to highlight the presence of a strong magnetic field at its surface through the presence of the first harmonic of the main pulsation mode of this object. Furthermore, the follow-up campaigns on J220029.08-074121.5 and J234843.30-094245.3 allowed to classify these two white dwarf as Hot DQ pulsators.
158

[en] LEAN COMMUNICATION-CENTERED DESIGN: A LIGHTWEIGHT DESIGN PROCESS / [pt] LEAN COMMUNICATION-CENTERED DESIGN: UM PROCESSO LEVE DE DESIGN CENTRADO NA COMUNICAÇÃO

DANIEL VITOR COSTA FERREIRA 11 January 2017 (has links)
[pt] O Lean Communication-Centered Design (LeanCCD) é um processo de design de Interação Humano-Computador (IHC) centrado na comunicação, que consiste na realização de um workshop, detalhamento de metas de usuários, combinação de modelos de interação com esboços em papel simulados com usuários, apoiados por guias e quadros. A IHC é uma área que estuda o projeto e uso de tecnologia computacional, em especial a interação entre computadores e pessoas. Este estudo adaptou o Communication-Centered Design (CCD) e o eXtreme Communication-Centered Design (eXCeeD), outros processos de design centrados na comunicação fundamentados na Engenharia Semiótica (EngSem). A EngSem é uma teoria de IHC que define a interação como um processo comunicativo entre designers e usuários mediado por computadores. Abordagens e processos fundamentados nessa teoria buscam favorecer a reflexão através da adoção de modelos, questões e métodos que não gerem diretamente uma resposta ou solução para o problema, mas apoiem o designer na exploração do espaço e da natureza do problema, bem como das restrições sobre soluções candidatas. A avaliação do LeanCCD em um estudo de caso na indústria observou dificuldade na condução das atividades e na aplicação correta de algumas técnicas e conceitos. Porém, diferentemente do eXCeeD, percebemos o uso sistemático das questões que favoreciam a reflexão devido ao auxílio dos quadros e guias propostos. / [en] Lean Communication-Centered Design (LeanCCD) is a Human-Computer Interaction (HCI) design process, which consists of conducting a workshop, detailing user goals, combining interaction models with paper sketches, and testing them with users, supported by guides and templates. This study adapted the Communication-Centered Design (CCD) and the eXtreme Communication-Centered Design (eXCeeD), other communication-centered design processes grounded on Semiotic Engineering (SemEng). SemEng defines the interaction as a computer-mediated communication process between designers and users. Approaches and processes based on SemEng are not used to directly yield the answer to a problem, but to increase the problem-solver s understanding of the problem itself and the implication it brings about. Process evaluation in a case study, in the industry, proved itself difficult, both in carrying out LeanCCD activities and in the correct application of some techniques and concepts. However, unlike eXCeeD, we were able to observe a systematic use of questions that contributed to designers reflection, aided by the proposed templates and guides.
159

Analýza fotovoltaických článků pomocí fotoluminiscence / Analyse of photovoltaic solar cells by the photoluminescence method

Baura, Tomáš January 2012 (has links)
This thesis deals with the analysis of solar cells by photoluminescence method. Photoluminescence method is based on the excitation of luminescence radiation of the solar cell material by an external excitation light source. This method can detect various types of defects in the material solar cells. The main objective is the design and realization of a measuring system defects of solar cells, which is based on this method. For excitation of luminescence is used LED array. For the detection of luminescence is used CCD camera with IR optical filter. To filter out the excitation light radiation is used disc screen and optical interrupter. The parameters and options of this measuring system are verified and characterized by test measuring for example the achievable rotation speed of screen and response of optical interrupter. At the end is tested detection of luminescence radiation of solar cells in the measuring system. The measured images are compared with the method of electroluminescence.
160

Moderní prostředky pro digitální snímání scény / Modern methods for digital scene capturing

Nováček, Petr January 2015 (has links)
The thesis composes conventional and modern methods for digital scene capturing. The target of the thesis is a comparison of CMOS with Bayer mask and Foveon X3 Merrill sensors followed by a design of algorithms for image fusion which can combine advantages of the both sensor types. The thesis starts with an introduction and a description of methods and processes leading to scene capturing. The next part deals with capturing a gallery of test images and with a comparison of both sensors based on the gallery images. Further there are algorithms designed for image fusion which can combine advantages of the selected sensors. The last part of the thesis is devoted to an evaluation of results and of the used algorithms.

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