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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.
91

Právní úprava ochrany ovzduší před znečišťováním ze stacionárních zdrojů / Legal regulation of air protection against pollution from stationary sources

Kunert, Petr January 2014 (has links)
The diploma thesis deals with legal regulation of air protection against pollution from stationary sources especially with the Act no. 201/2012 Coll. on the Protection of Air. The opening chapter introduces to the issues and systematics of the diploma thesis. The second chapter contains the overview of the most important pollutants with their impacts on human health and the environment. The third chapter concerns the international regulation of the air pollution protection including the European Union regulation. The fourth chapter describes the development of the air protection legal regulation in the Czech Republic. The fifth chapter gives attention to the definition of the stationary source of pollution. The sixth chapter deals with the level of pollution and the tools connected with this level. The seventh chapter is about the regulation of the sources of pollution. The final chapter summarizes the previous text and contains the evaluation of the legal regulation of the air protection.
92

Problematika nevyjmenovaných zdrojů dle nové právní úpravy ochrany ovzduší / The Issues of unlisted Sources of Air Pollution according to the new Air Protection Act

Trnková, Zuzana January 2014 (has links)
Diploma thesis focuses on air protection, especially on the issues of unlisted sources of air pollution according to the czech Air Protection Act. It aims on small stationary sources of pollution that are subject to a softer regulation then huge polluters. Important group of small stationary sources are boilers used in homes to heat them up. In the case, that the operator of the sources does not fulfil his/her responsabilities according to the Air Protection Act, he/she can cause damage to the environment and endanger neighbours health. But because of the right of privacy it is not possible to control the source. The paper analysis the possibilities to resolve the dilemma between three constitutional rights - right of privacy against right to a favourable environment and right to the protection of health. Powered by TCPDF (www.tcpdf.org)
93

Optimalizace funkce obnovitelných zdrojů elektrické energie na bázi palivových článků, akumulátorů a FV panelů pro malé výkony. / Optimization of operation of renewable electric energy sources based on fuel cells, accumulators and FV panels for small powers.

Holeček, Martin January 2016 (has links)
The first part of the research is motivated to provide citations deeper to the literature of optimal control principles that could be linked to the system optimization problem, discuss these principles and various ways to apply them. Then we describe one fuel cell, accumulator and photovoltaic standalone system along with the most used equations from the literature. Next, we formulate the problem of optimal control for this system to optimize the system financial cost in the best case and we process to describe and discuss the numerical optimal control algorithm - multiple shooting - that will be used to solve the problem, that was not used in literature so far in conjunction with the problem. The codes and numerical simulations are also provided. Powered by TCPDF (www.tcpdf.org)
94

Détection d'objets stationnaires par une paire de caméras PTZ / Stationary object detection by a pair of ptz cameras

Guillot, Constant 23 January 2012 (has links)
L’analyse vidéo pour la vidéo-surveillance nécessite d’avoir une bonne résolution pour pouvoir analyser les flux vidéo avec un maximum de robustesse. Dans le contexte de la détection d’objets stationnaires dans les grandes zones, telles que les parkings, le compromis entre la largeur du champ d’observation et la bonne résolution est difficile avec un nombre limité de caméras. Nous allons utiliser une paire de caméras à focale variable de type Pan-Tilt-Zoom (PTZ). Les caméras parcourent un ensemble de positions (pan, tilt, zoom) prédéfinies afin de couvrir l’ensemble de la scène à une résolution adaptée. Chacune de ces positions peut être vue comme une caméra stationnaire à très faible taux de rafraîchissement. Dans un premier temps notre approche considère les positions des PTZ comme des caméras indépendantes. Une soustraction de fond robuste aux changements de luminosité reposant sur une grille de descripteurs SURF est effectuée pour séparer le fond du premier plan. La détection des objets stationnaires est effectuée par ré-identification des descripteurs à un modèle du premier plan. Dans un deuxième temps afin de filtrer certaines fausses alarmes et pouvoir localiser les objets en 3D une phase de mise en correspondance des silhouettes entre les deux caméras et effectuée. Les silhouettes des objets stationnaires sont placées dans un repère commun aux deux caméras en coordonnées rectifiées. Afin de pouvoir gérer les erreurs de segmentation, des groupes de silhouettes s’expliquant mutuellement et provenant des deux caméras sont alors formés. Chacun de ces groupes (le plus souvent constitué d’une silhouette de chaque caméra, mais parfois plus) correspond à un objet stationnaire. La triangulation des points frontière haut et bas permet ensuite d’accéder à sa localisation 3D et à sa taille. / Video analysis for video surveillance needs a good resolution in order to analyse video streams with a maximum of robustness. In the context of stationary object detection in wide areas a good compromise between a limited number of cameras and a high coverage of the area is hard to achieve. Here we use a pair of Pan-Tilt-Zoom (PTZ) cameras whose parameter (pan, tilt and zoom) can change. The cameras go through a predefined set of parameters chosen such that the entire scene is covered at an adapted resolution. For each triplet of parameters a camera can be assimilated to a stationary camera with a very low frame-rate and is referred to as a view. First each view is considered independently. A background subtraction algorithm, robust to changes in illumination and based on a grid of SURF descriptors, is proposed in order to separate background from foreground. Then the detection and segmentation of stationary objects is done by reidentifying foreground descriptor to a foreground model. Then in order to filter out false alarms and to localise the objects in the3D world, the detected stationary silhouettes are matched between the two cameras. To remain robust to segmentation errors, instead of matched a silhouette to another, groups of silhouettes from the two cameras and mutually explaining each other are matched. Each of the groups then correspond to a stationary object. Finally the triangulation of the top and bottom points of the silhouettes gives an estimation of the position and size of the object.
95

Podnikatelský plán MSP - distribuce automatických parkovacích systémů v podobě výhradního zastoupení / Business plan SME - distribution of automatic parking systems on the basis of master distributorship

Kouble, Jiří January 2010 (has links)
Thesis first focuses on the theoretical level of the structure of the business plan and describes the characteristics and specifics of the business as a master distributorship. The practical part analyzes on the real firm creating of a business plan and accurate process of implementation of the business plan, which seeks to help resolve the problem of "stationary traffic".
96

Investigation of pore size effects at separation of oligonucleotides using Ion-pair RP HPLC : Examining of how the particle pore size of the stationary phase affects separations of oligonucleotides in therapeutic range / Undersökning av porstorlekens påverkan på separationen av oligonukleotider med IP-RP HPLC : Granskning hur den stationära fasens partikel porstorlek påverkar separationen av oligonukleotider inom tänkbar längd för läkemedel

Jonsson, Alexander January 2019 (has links)
Oligonucleotides may become a new class of therapies with the potential of curing many today untreatable diseases. Oligonucleotides becomes increasingly more difficult to separate with an increase in length since the relative difference in retention of these very similar compounds becomes increasingly smaller. Therefore, coelution of impurities formed during synthesis may result in insufficient purity, which is necessary for therapeutic treatments. Oligonucleotides are also relatively large biomolecules, possibly consisting of hundreds of nucleotides. As a result, oligonucleotides may have limited diffusion through the stationary phase pores which affects separation performance. Surprisingly few studies have be published in this research area and a wider knowledge in how this affects separation is needed. In this master thesis, separation of deoxythymidine oligonucleotides with 5-30 mers in length were separated with 60, 100, 200 and 300 Å pore size reversed phase C4 columns. It was concluded that pore size resulted in more restricted diffusion if insufficient pore size was used. Poor peak performance was also observed with too large pore sizes which lead to less efficient separations.
97

Conception et réalisation d’un micro-spectromètre dans l’infrarouge / Design and realization of a compact infrared spectrometer

Gillard, Frédéric 16 March 2012 (has links)
Pour répondre au besoin de miniaturisation des spectromètres de terrain travaillant dans l’infrarouge, l’ONERA a développé un nouveau concept baptisé MICROSPOC. Ce dispositif est un détecteur infrarouge auquel a été intégré un interféromètre à deux ondes, constituant un spectromètre statique par transformée de Fourier. Ce plan focal infrarouge modifié, qui fusionne la fonction interférométrique et la fonction de détection, associé à une optique de tête simplifiée, permet d’envisager la réalisation d’instruments très compacts. L’objectif de cette thèse est de concevoir un spectromètre infrarouge miniature basé sur le dispositif MICROSPOC. Dans un premier temps, un travail théorique a été mené, dans l’objectif de dimensionner un système optique très compact. Notre choix s’étant orienté vers un système optique de collection (le détecteur voit une source étendue à distance finie), l’étude de l’acceptance angulaire de MICROSPOC dans ces conditions d’éclairement est indispensable afin de prévoir le contraste et la forme des franges d’interférence. Les résultats montreront la grande acceptance angulaire de MICROSPOC.Dans un second temps, un démonstrateur basé sur un composant MICROSPOC et sur le système optique simplifié a été réalisé. Ce démonstrateur a été caractérisé en laboratoire puis utilisé sur le terrain lors d’une campagne de mesures. Ces différentes exploitations ont montré la robustesse de l’instrument malgré l’obtention d’interférogrammes présentant divers défauts.Dans un troisième temps, une chaîne de traitement a été développée afin d’estimer un spectre à partir d’un interférogramme obtenu à l’aide du démonstrateur. Du fait des caractéristiques intrinsèques de MICROSPOC, la transformée de Fourier n’est pas la meilleure solution pour estimer un spectre. Nous l’avons montré en nous intéressant aux effets des disparités de longueur d’onde de coupure du détecteur sur l’estimation d’un spectre. Nous nous sommes alors tournés vers une approche consistant à utiliser la caractérisation spectrale de l’instrument pour inverser la mesure. Cette approche donne des résultats satisfaisants.Enfin, le but principal de cette thèse a été élargi par la conception et la réalisation de différents démonstrateurs combinant une fonction d’imagerie à une fonction de spectrométrie. Les premières pistes pour la conception d’un spectromètre qui tient dans la main ont été données. / In order to satisfy the need for handheld infrared spectrometers, the ONERA developed a new concept called MICROSPOC. This device is an infrared focal plane array with a built-in two-wave wedge-like interferometer and forms a static Fourier-transform spectrometer. This modified focal plane array, which merges the detection function and the interferometric function, in association with a simplified optical system, allows to consider the realisation of a much compact instrument. The goal of this thesis is to design and to realize a miniaturized infrared spectrometer based on the MICROSPOC concept.Firstly, a theoritical work has been led in order to design a compact optical system. Since we have chosen a collection optical system (the focal plane array sees an extended source placed at a finite distance), the study of MICROSPOC angular acceptance in these lightening conditions is needed in order to predict the contrast and the shape of interference fringes. The huge angular acceptance of MICROSPOC will be established with the results of this study.Secondly, a demonstrator based on MICROSPOC device and on the simplified optical system has been realized. This demonstrator has been caracterized in the laboratory and used in real conditions of a measurement campaign. These different exploitations have shown the robustness of the instrument despite some defaults on acquired interferograms.Then, a processing chain has been developed in order to estimate a spectrum from an interferogram acquired with our demonstrator. Considering the MICROSPOC’s own characteristics, the Fourier-transform is not the best way to estimate a spectrum. We have come to this conclusion by studying the effects of cut-off wavelenghts disparities of the detector on the spectrum estimation. At this point we have considered an approach that consists of using the spectral characterization of the instrument in order to inverse the measure. This approach gives satisfying results.Finaly, the main goal has been widened with the design and the realisation of other instruments that combine a spectrometric function and a imaging function. The first elements for the design of a handheld spectrometer have been given.
98

Teorema de Furstenberg sobre o produto aleatório de matrizes / Furstenberg theorem on the random product of matrices

Maquera, Herbert Milton Ccalle 31 July 2018 (has links)
Nesta dissertação estudamos de um ponto de vista probabilístico, o comportamento assintótico de sistemas dinâmicos. Um exemplo simples de formular e profundo é o estudo de produto aleatório de matrizes (FURSTENBERG; KESTEN, 1960). Utilizaremos como ferramenta o estudo dos cociclos lineares, posteriormente mediante o Teorema de Furstenberg-Kesten definiremos o expoente de Lyapunov do cociclo, em seguida enunciamos e provamos o Teorema Ergódico Multiplicativo de Oseledets o qual nos permite entender o comportamento das órbitas típicas para um cociclo dado F : M x R2 → M x R2. O Teorema de Fusrtenberg-Kesten fornece informações sobre o crescimento das matrizes An(x), enquanto o Teorema de Oseledets descreve o comportamento assintótico dos vetores An(x).v. Finalmente provamos o teorema principal desta dissertação, o Teorema de Furstenberg o qual diz que na maioria dos casos o maior expoente de Lyapunov é positivo (FURSTENBERG, 1963). / In this thesis we study from a probabilistic point of view, the asymptotic behavior of dynamic systems, a deep and simple example is the random product of matrices (FURSTENBERG; KESTEN, 1960). We will use as a tool, the study of linear cocycles, later using the Furstenberg- Kesten Theorem we will define the Lyapunov exponent of the cocycle, then we enunciate and prove the Multiplicative Ergodic Theorem of Oseledets which allow us to understand the behavior of the typical orbits for a given cocycle F : M x R2 → M x R2. The Fusrtenberg- Kesten theorem provides information on the growth of the matrices A(x), while the theorems of Oseledets describe the asymptotic behavior of the vectors An(x).v. Finally we prove our main theorem, Furstenbergs Theorem which states that in most cases the greatest exponent of Lyapunov is positive (FURSTENBERG, 1963).
99

Teorema de Furstenberg sobre o produto aleatório de matrizes / Furstenberg theorem on the random product of matrices

Herbert Milton Ccalle Maquera 31 July 2018 (has links)
Nesta dissertação estudamos de um ponto de vista probabilístico, o comportamento assintótico de sistemas dinâmicos. Um exemplo simples de formular e profundo é o estudo de produto aleatório de matrizes (FURSTENBERG; KESTEN, 1960). Utilizaremos como ferramenta o estudo dos cociclos lineares, posteriormente mediante o Teorema de Furstenberg-Kesten definiremos o expoente de Lyapunov do cociclo, em seguida enunciamos e provamos o Teorema Ergódico Multiplicativo de Oseledets o qual nos permite entender o comportamento das órbitas típicas para um cociclo dado F : M x R2 → M x R2. O Teorema de Fusrtenberg-Kesten fornece informações sobre o crescimento das matrizes An(x), enquanto o Teorema de Oseledets descreve o comportamento assintótico dos vetores An(x).v. Finalmente provamos o teorema principal desta dissertação, o Teorema de Furstenberg o qual diz que na maioria dos casos o maior expoente de Lyapunov é positivo (FURSTENBERG, 1963). / In this thesis we study from a probabilistic point of view, the asymptotic behavior of dynamic systems, a deep and simple example is the random product of matrices (FURSTENBERG; KESTEN, 1960). We will use as a tool, the study of linear cocycles, later using the Furstenberg- Kesten Theorem we will define the Lyapunov exponent of the cocycle, then we enunciate and prove the Multiplicative Ergodic Theorem of Oseledets which allow us to understand the behavior of the typical orbits for a given cocycle F : M x R2 → M x R2. The Fusrtenberg- Kesten theorem provides information on the growth of the matrices A(x), while the theorems of Oseledets describe the asymptotic behavior of the vectors An(x).v. Finally we prove our main theorem, Furstenbergs Theorem which states that in most cases the greatest exponent of Lyapunov is positive (FURSTENBERG, 1963).
100

Techniques for condition monitoring using cyclo-non-stationary signals

Barbini, Leonardo January 2018 (has links)
Condition based maintenance is becoming increasingly popular in many industrial contexts, offering substantial savings and minimising accidental damage. When applied to rotating machinery, its most common tool is vibration analysis, which relies on well-established mathematical models rooted in the theory of cyclo-non-stationary processes. However, the extraction of diagnostic information from the real world vibration signals is a delicate task requiring the application of sophisticated signal processing techniques, tailored for specific machines operating under restricted conditions. Such difficulty in the current state of the art of vibration analysis forces the industry to apply methods with reduced diagnostic capabilities but higher adaptability. However in doing so most of the potential of vibration analysis is lost and advanced techniques become of use only for academic endeavours. The aim of this document is to reduce the gap between industrial and academic applications of condition monitoring, offering ductile and automated tools which still show high detection capabilities. Three main lines of research are presented in this document. Firstly, the implementation of stochastic resonance in an electrical circuit to enhance directly the analog signal from an accelerometer, in order to lower the computational requirements in the next digital signal processing step. Secondly, the extension of already well-established digital signal processing techniques, cepstral prewhitening and spectral kurtosis, to a wider range of operating conditions, proving their effectiveness in the case of non-stationary speeds. Thirdly, the main contribution of the thesis: the introduction of two novel techniques capable of separating the vibrations of a defective component from the overall vibrations of the machine, by means of a threshold in the amplitude spectrum. After the separation, the cyclic content of the vibration signal is extracted and the thresholded signals provide an enhanced detection. The two proposed methods, phase editing and amplitude cyclic frequency decomposition, are both intuitive and of low computational complexity, but show the same capabilities as more sophisticated state of the art techniques. Furthermore, all these tools have been successfully tested on numerically simulated signals as well as on real vibration data from different machinery, lasting from laboratory test rigs to wind turbines drive-trains and aircraft engines. So in conclusion, the proposed techniques are a promising step toward the full exploitation of condition based maintenance in industrial contexts.

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