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Klíčivost a vzcházivost semen kosatce sibiřského (Iris sibirica L.) v závislosti na typu managementu / Seed germination and seedling recruitment of Iris sibirica depending on the type of managementHOŘEJŠÍ, Edita January 2018 (has links)
This work continue on a bachelor's work which investigated production characteristics of the plant species Siberian Iris (Iris sibirica). The aims of the presented work are reproductive properties by seeds of Siberian Iris in relation to the seed germination and with various meadow managements. Seeds of Siberian Iris (collected in 2015 and 2016) were investigated in laboratory condition and at meadow near the pond Dolní Stržený (Dlouhá Lhota, of the Tábor District). Seeds were divided into groups according to 4 treatments: without intervention, scarification, thermal stratification and cold stratification. The field experiment runs from September 2016 to August 2017.The aim was to find out the most appropriate type of management (mowing, disturbance) that would promote seed germination and seedling recruitment. Results from the both experiments: a positive effect of germination after the scarification, better recruitment of seeds in square without intervention, seeds probably needs to be stored for a longer period before sowing. These results cannot be generalized, because small number of repetitions were performed. All the obtained data was discussed and recommendations for the plant management were formulated.
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Reconhecimento de pessoas por meio da região interna da íris /Rogéri, Jonathan Gustavo. January 2011 (has links)
Orientador: Aledir Silveira Pereira / Banca: Aparecido Nilceu Marana / Banca: Evandro Luís Linhari Rodrigues / Resumo: Nos últimos anos, a segurança tornou-se uma preocupação constante da grande maioria das pessoas. Os sistemas biométricos vem ganhando destaque em soluções ligadas à segurança, uma vez que tratam de características físicas e comportamentais para reconhecimento dos indivíduos e permissões de acesso. Este trabalho objetivou a proposição e implementação de um método para reconhecimento de indivíduos por meio de características contidas na região interna da íris com um alto percentual de exatidão no reconhecimento e uma grande diminuição no tempo de processamento, se comparado aos demais métodos encontrados na literatura. No método proposto foram utilizados operadores de morfologia matemática para localização da íris, wavelet de log-Gabor para extração das características e a distância de Hamming para o reconhecimento. Os resultados experimentais obtidos utilizando a base de dados CASIA mostraram que o método é confiável e seguro, além de se destacar com relação ao baixo custo computacional / Abstract: In the recent years, the security became a constant concern of most people. Biometric systems have been highlighted in solutions related to security, since they deal with physical and behavioral characteristics for individuals recognition and access permissions. This work aims at the implementation of a method for individuals recognition based on the characteristics of the inner region of the iris, seeking a high percentage of accuracy in the recognition and a great reduction in the processing time, as compared to other methods published so far. We use mathematical morphology to search the iris in the image, the log-Gabor wavelet for feature extraction and the Hamming distance for recognition. The experimental results obtained from CASIA database show that the method is safe and reliable, and stand out with regard to the low computational cost / Mestre
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Estudo comparativo da transformada wavelet no reconhecimento de padrões da íris humana / A comparative study of wavelet transform in human iris pattern recognitionCélio Ricardo Castelano 21 September 2006 (has links)
Neste trabalho é apresentado um método para reconhecimento de seres humanos através da textura da íris. A imagem do olho é processada através da análise do gradiente, com uma técnica de dispersão aleatória de sementes. Um vetor de características é extraído para cada íris, baseado na análise dos componentes wavelet em diversos níveis de decomposição. Para se mensurar as distâncias entre esses vetores foi utilizado o cálculo da distância Euclidiana, gerando-se curvas recall x precision para se medir a eficiência do método desenvolvido. Os resultados obtidos com algumas famílias wavelets demonstraram que o método proposto é capaz de realizar o reconhecimento humano através da íris com uma precisão eficiente. / This work presents a method for recognition of human beings by iris texture. The image of the eye is processed through gradient analysis, based on a random dispersion of seeds. So, it is extracted a feature vector for each iris based on wavelet transform in some levels of decomposition. To estimate the distances between these vectors it was used the Euclidean distance, and recall x precision curves are generated to measure the efficiency of the developed method. The results gotten with some wavelets families had demonstrated that the proposed methodology is capable to do human recognition through the iris with an efficient precision.
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Robustez em um sistema de detecção e rastreamento de olhos para implementação de uma interface humano-computador.Silva, André Brasiliano da 21 August 2014 (has links)
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Previous issue date: 2014-08-21 / Eye tracking is an important issue for Human Computer interaction, mainly for users with hand-eye coordination problems. The work presented here shows a low cost and
robust eye tracking system capable to work with an HD stream. The implementations used in this work over the base system present diferent techniques in all stages, from face detection to iris detection. Local processing is used in most stages in this implementation, delimiting the region of interest (ROI) for face detection, eye detection and iris detection. The system robustness allow the eye tracking system to control the mouse using eye movements allowing disable users to communicate through a communication interface. The hardware required is simple and based in an high definition webcam. The face detection and eye detection processes are based on the Viola Jones technique; iris detection and tracking are based on the Hough Transform. The usage of local processing reduces the computational cost and even working with high definition stream leads to a performance 33% better than the base system. The system presented here was compared with a commercial system and a set of equipment were tested in order to dene the best set up for the eye tracking system and to validate the work presented here. Future work is presented at the end in order to allow the project continuity. / O rastreamento ocular para usuários com problemas motores é um estudo importante na área de Interface Humano-Computador (IHC). Com o objetivo de fornecer um sistema de rastreamento ocular de baixo custo, este trabalho apresenta uma nova abordagem para um sistema robusto e com alto desempenho. Com relação ao trabalho base para esta pesquisa, a implementação proposta contém inovações em todas as etapas do processo envolvendo o rastreamento ocular, desde a detecção da região da face e dos olhos até a detecção da íris. Neste trabalho, foi utilizado o conceito de processamento local, delimitando as regiões de interesse em todas as etapas do processo: detecção da região da face, região dos olhos e região da íris. Este trabalho permite que pessoas possam efetuar ações controlando o mouse através do movimento dos olhos em uma interface de rastreamento ocular, utilizando apenas equipamentos de uso comum, como, por exemplo, uma webcam. O processo de detecção da face e detecção ocular foi feito através da técnica de Viola e Jones. Para a detecção e rastreamento da íris foi utilizada a Transformada de Hough, e utilização de regiões de interesse com o objetivo de limitar a área de processamento da imagem, e consequentemente, o custo computacional, resultando em uma aplicação com um melhor desempenho e robustez em todas as etapas. Obteve-se um ganho de até 33% em relação ao tempo de processamento do sistema, quando comparado com o sistema base, porém, operando com imagens em alta definição. Foi realizada ainda uma comparação com sistemas de rastreamento ocular de uso comercial e diferentes tipos de equipamentos para validar as técnicas estudadas neste trabalho.
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Democratic pluralism as engagement and encounter : asymmetric reciprocity, reflexivity, and agonismKerimov, Farhad January 2016 (has links)
This thesis shows how democratic politics requires a commitment to pluralism as engagement and encounter of the other in their otherness. I contend that it is necessary to commit to such an idea of pluralism because of the problem of incomplete understanding. I establish this premise by drawing on Hans-Georg Gadamer’s account of human finitude. Based on this premise, I argue that the instantiation of Gadamer’s principle of openness leads democratic politics to pluralism as engagement and encounter of the other. Further, I develop accounts of asymmetric reciprocity, reflexivity, and agonism as modes of democratic politics that instantiate the principle of openness. In chapter 1, I establish discourse as a necessary element for democratic politics by drawing from the way Jurgen Habermas uses ‘discourse ethics’ to address the problems of understanding in plural societies. In chapter 2, I demonstrate how incomplete understanding poses a problem for discourse and gives rise to interpretive conflicts by drawing from Gadamer’s account of human finitude. Here I also develop an account of openness as a suitable principle for beings with incomplete understanding based on Gadamer’s idea of hermeneutical experience. In chapters 3-5, I develop accounts of asymmetric reciprocity, reflexivity, and agonism as modes of democratic politics that instantiate the principle of openness. I do so by drawing from Iris Young’s, John Dryzek’s, and Chantal Mouffe’s approaches to the problems that plurality poses to discourse ethics and democratic politics.
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Fusion techniques for iris recognition in degraded sequences / Techniques de fusion pour la reconnaissance de personne par l’iris dans des séquences dégradéesOthman, Nadia 11 March 2016 (has links)
Parmi les diverses modalités biométriques qui permettent l'identification des personnes, l'iris est considéré comme très fiable, avec un taux d'erreur remarquablement faible. Toutefois, ce niveau élevé de performances est obtenu en contrôlant la qualité des images acquises et en imposant de fortes contraintes à la personne (être statique et à proximité de la caméra). Cependant, dans de nombreuses applications de sécurité comme les contrôles d'accès, ces contraintes ne sont plus adaptées. Les images résultantes souffrent alors de diverses dégradations (manque de résolution, artefacts...) qui affectent négativement les taux de reconnaissance. Pour contourner ce problème, il est possible d’exploiter la redondance de l’information découlant de la disponibilité de plusieurs images du même œil dans la séquence enregistrée. Cette thèse se concentre sur la façon de fusionner ces informations, afin d'améliorer les performances. Dans la littérature, diverses méthodes de fusion ont été proposées. Cependant, elles s’accordent sur le fait que la qualité des images utilisées dans la fusion est un facteur crucial pour sa réussite. Plusieurs facteurs de qualité doivent être pris en considération et différentes méthodes ont été proposées pour les quantifier. Ces mesures de qualité sont généralement combinées pour obtenir une valeur unique et globale. Cependant, il n'existe pas de méthode de combinaison universelle et des connaissances a priori doivent être utilisées, ce qui rend le problème non trivial. Pour faire face à ces limites, nous proposons une nouvelle manière de mesurer et d'intégrer des mesures de qualité dans un schéma de fusion d'images, basé sur une approche de super-résolution. Cette stratégie permet de remédier à deux problèmes courants en reconnaissance par l'iris: le manque de résolution et la présence d’artefacts dans les images d'iris. La première partie de la thèse consiste en l’élaboration d’une mesure de qualité pertinente pour quantifier la qualité d’image d’iris. Elle repose sur une mesure statistique locale de la texture de l’iris grâce à un modèle de mélange de Gaussienne. L'intérêt de notre mesure est 1) sa simplicité, 2) son calcul ne nécessite pas d'identifier a priori les types de dégradations, 3) son unicité, évitant ainsi l’estimation de plusieurs facteurs de qualité et un schéma de combinaison associé et 4) sa capacité à prendre en compte la qualité intrinsèque des images mais aussi, et surtout, les défauts liés à une mauvaise segmentation de la zone d’iris. Dans la deuxième partie de la thèse, nous proposons de nouvelles approches de fusion basées sur des mesures de qualité. Tout d’abord, notre métrique est utilisée comme une mesure de qualité globale de deux façons différentes: 1) comme outil de sélection pour détecter les meilleures images de la séquence et 2) comme facteur de pondération au niveau pixel dans le schéma de super-résolution pour donner plus d'importance aux images de bonnes qualités. Puis, profitant du caractère local de notre mesure de qualité, nous proposons un schéma de fusion original basé sur une pondération locale au niveau pixel, permettant ainsi de prendre en compte le fait que les dégradations peuvent varier d’une sous partie à une autre. Ainsi, les zones de bonne qualité contribueront davantage à la reconstruction de l'image fusionnée que les zones présentant des artéfacts. Par conséquent, l'image résultante sera de meilleure qualité et pourra donc permettre d'assurer de meilleures performances en reconnaissance. L'efficacité des approches proposées est démontrée sur plusieurs bases de données couramment utilisées: MBGC, Casia-Iris-Thousand et QFIRE à trois distances différentes. Nous étudions séparément l'amélioration apportée par la super-résolution, la qualité globale, puis locale dans le processus de fusion. Les résultats montrent une amélioration importante apportée par l'utilisation de la qualité globale, amélioration qui est encore augmentée en utilisant la qualité locale / Among the large number of biometric modalities, iris is considered as a very reliable biometrics with a remarkably low error rate. The excellent performance of iris recognition systems are obtained by controlling the quality of the captured images and by imposing certain constraints on users, such as standing at a close fixed distance from the camera. However, in many real-world applications such as control access and airport boarding these constraints are no longer suitable. In such non ideal conditions, the resulting iris images suffer from diverse degradations which have a negative impact on the recognition rate. One way to try to circumvent this bad situation is to use some redundancy arising from the availability of several images of the same eye in the recorded sequence. Therefore, this thesis focuses on how to fuse the information available in the sequence in order to improve the performance. In the literature, diverse schemes of fusion have been proposed. However, they agree on the fact that the quality of the used images in the fusion process is an important factor for its success in increasing the recognition rate. Therefore, researchers concentrated their efforts in the estimation of image quality to weight each image in the fusion process according to its quality. There are various iris quality factors to be considered and diverse methods have been proposed for quantifying these criteria. These quality measures are generally combined to one unique value: a global quality. However, there is no universal combination scheme to do so and some a priori knowledge has to be inserted, which is not a trivial task. To deal with these drawbacks, in this thesis we propose of a novel way of measuring and integrating quality measures in a super-resolution approach, aiming at improving the performance. This strategy can handle two types of issues for iris recognition: the lack of resolution and the presence of various artifacts in the captured iris images. The first part of the doctoral work consists in elaborating a relevant quality metric able to quantify locally the quality of the iris images. Our measure relies on a Gaussian Mixture Model estimation of clean iris texture distribution. The interest of our quality measure is 1) its simplicity, 2) its computation does not require identifying in advance the type of degradations that can occur in the iris image, 3) its uniqueness, avoiding thus the computation of several quality metrics and associated combination rule and 4) its ability to measure the intrinsic quality and to specially detect segmentation errors. In the second part of the thesis, we propose two novel quality-based fusion schemes. Firstly, we suggest using our quality metric as a global measure in the fusion process in two ways: as a selection tool for detecting the best images and as a weighting factor at the pixel-level in the super-resolution scheme. In the last case, the contribution of each image of the sequence in final fused image will only depend on its overall quality. Secondly, taking advantage of the localness of our quality measure, we propose an original fusion scheme based on a local weighting at the pixel-level, allowing us to take into account the fact that degradations can be different in diverse parts of the iris image. This means that regions free from occlusions will contribute more in the image reconstruction than regions with artefacts. Thus, the quality of the fused image will be optimized in order to improve the performance. The effectiveness of the proposed approaches is shown on several databases commonly used: MBGC, Casia-Iris-Thousand and QFIRE at three different distances: 5, 7 and 11 feet. We separately investigate the improvement brought by the super-resolution, the global quality and the local quality in the fusion process. In particular, the results show the important improvement brought by the use of the global quality, improvement that is even increased using the local quality
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Ovládání PC pomocí očí / PC control via eyesNeuwirth, Tomáš January 2011 (has links)
The presented master thesis deals with the evaluation of the position of the iris compared with surroundings of the eye. This technique is supposed to be use for computer control. The created software works in real-time mode, the pictures are taken with an ordinary webcam. The first part of the work presents basic algorithms used in computer vision for edit of images. The following part is focused on abilities of methods to find the face, eyes and to detect the iris. The detection and the subsequent separation of the face is based on the recognition of skin colour in the YCbCr color space. The position of eye is then searched in the face by Haar-like features. The darkest part of the eye is found by horizontal projection from surroundings and the seed point is started from this place. From the area which is filled by the seed method (Flood Fill) and which shows the iris, the cursor movement is controlled by obtained x and y position.
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Analyzátor rádiových kanálů IEEE 802.15.4 / Analyzer of IEEE 802.15.4 radio channelsPokorný, Jiří January 2012 (has links)
The master’s thesis deals with development of the radio channel analyser operating in the unlicensed 2.4 GHz band according to IEEE 802.15.4 standard. The analyzer will contain two basic functions, namely energy detection of channels and analysation of selected channel. Detection of energy will be solved by selection between simple graph and text list on display. Based on information about the occupancy of channels the user can decide which channel would be set up. During the receiving of valid frame the source address, signal strength and signal quality will be stored. At the end the processor will show these data on display. For controlling the device will be installed two LEDs and four buttons.
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Určení a vizualizace souřadného systému rohovky během implantace čočky / Identification and visualization of the coordinate system of the cornea during lens implantationHudec, Jiří January 2015 (has links)
The dissertation describes the method of inserting polar-axis system into the video recording of cataract operation at the Geminy Eye Surgery, Zlin. At the theoretical part, it discusses requirements for inserting the polar-axis system including elimination of eye rotary movements captured by slit lamp. Then the emphasis is also on the speed of data processing. The practical part of the dissertation, focuses on the creating the method for detection of centers at the slit lamp picture, as well as video sequence and a method that eliminates potential eye rotation. For designing the program solution, following methods were used: Otsu method, Hough transformation method, method of two vertical projections, and crosscorrelation method. In total, the program solution was tested and analyzed in Matlab program on anonymous data set of 22 eyes.
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Generování kryptografického klíče z biometrických vlastností oka / Generation of Cryptographic Key from Eye Biometric FeaturesSemerád, Lukáš January 2014 (has links)
The main topic of the thesis is creation of formulas for the amount of information entropy in biometric characteristics of iris and retina. This field of science in biometrics named above is unstudied yet, so the thesis tries to initiate research in this direction. The thesis also discusses the historical context of security and identification fields according to biometric characteristics of a human being with an overlap for potential usage in biometrics of iris and retina. The Daugman’s algorithm for converting iris image into the binary code which can be used as a cryptographic key is discussed in detail. An application implementing this conversion is also a part of the thesis.
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