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1
Tavakoli, Hanif. "A High Frequency Transformer Winding Model for FRA Applications." Licentiate thesis, Stockholm : Skolan för elektro- och systemteknik, Kungliga Tekniska högskolan, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-11178.
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Tavakoli, Hanif. "An FRA Transformer Model with Application on Time Domain Reflectometry." Doctoral thesis, KTH, Elektroteknisk teori och konstruktion, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-48568.
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Frequency response analysis (FRA) is a frequency-domain method which is used to detect mechanical faults in transformers. The frequency response of a transformer is determined by its geometry and material properties, and it can be considered as the transformer’s fingerprint. If there are any mechanical changes in the transformer, for example if the windings are moved or distorted, its fingerprint will also be changed so, theoretically, mechanical changes in the transformer can be detected with FRA. A problem with FRA is the fact that there is no general agreement about how to interpret the measurement results for detection of winding damages. For instance, the interpretation of measurement results has still not been standardized.The overall goal of this thesis is to try to enhance the understanding of the information contained in FRA measurements. This has been done in two ways: (1) by examining the FRA method for (much) higher frequencies than what is usual, and (2) by developing a new method in which FRA is combined with the ideas of Time Domain Reflectometry (TDR). As tools for carrying out the above mentioned steps, models for the magnetic core and the winding have been developed and verified by comparison to measurements.The usual upper frequency limit for FRA is around 2 MHz, which in this thesis has been extended by an order of magnitude in order to detect and interpret new phenomena that emerge at high frequencies and to investigate the potential of this high-frequency region for detection of winding deteriorations.Further, in the above-mentioned new method developed in this thesis, FRA and TDR are combined as a step towards an easier and more intuitive detection and localization of faults in transformer windings, where frequency response measurements are visualized in the time domain in order to facilitate their interpretation.QC 20111122
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Завадський, Богдан Володимирович, and Bohdan Zavadskyi. "Оптимізація системи електропостачання трансформаторної підстанції 110/10 кВ." Master's thesis, Тернопільський національний технічний університет імені Івана Пулюя, кафедра електричної інженерії,Тернопіль, Україна, 2021. http://elartu.tntu.edu.ua/handle/lib/36648.
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У зв'язку зі зростанням технологічного прогресу, розумні системи все
частіше використовуються в різних сферах людської діяльності. Розумні
системи дозволяють технікам, адміністраторам і менеджерам контролювати і
продуктивність і роботу пристроїв з безпечної відстані. Сфера енергетики не є
винятком. Розподільчі мережі компанії повинні управляти розподільною
мережею, яка є однією з найважливіших частин електромережі [1].
В даний час для загального розвитку промисловості країни необхідні
трансформації в енергетичному секторі. Завдання цифровізації енергетики було
поставлено на найвищому рівні[2].
Традиційно пропускна здатність мережі визначається на основі пікового
використання. Таке використання може відображати споживання енергії лише
протягом декількох годин на рік; Наприклад, пізно вночі посеред зими.
Дорогих мережевих посилень в майбутньому можна уникнути, якщо ці піки
енергоспоживання можуть бути компенсовані. Це починає відбуватися в міру
того, як структура виробництва енергії змінюється і стає все більш залежною
від поновлюваних джерел енергії, а не від традиційних електростанцій. Крім
того, домогосподарства мають потенціал стати автономними, збільшуючи
доступність внутрішнього зберігання та виробництва енергії [3].
Розумні лічильники повідомлять енергопостачальну організацію про збої
передачі електроенергії, що допоможе поліпшити обслуговування клієнтів.
Замість того, щоб чекати, поки перший споживач повідомить про це, мережеві
організації зможуть реагувати, як тільки буде отримано перше попередження
про відмову розумного лічильника. Розумні лічильники також повідомлять
суб'єктів ринку електроенергії, якщо якість електропостачання, наприклад,
рівень напруги, виходить за межі заданих рівнів. Це допоможе енергосистемам
краще зрозуміти якість їх поставок і усунути недоліки [4].У кваліфікаційній роботі магістра здійснено розробку технічних заходів щодо оптимізації системи електропостачання мережі трансформаторної підстанції 110/10 кВ. Встановлено, що необхідно забезпечити мережу ПС 110/10 кВ засобами дистанційного моніторингу параметрів на усіх рівнях. Отримані дані для місць розташування засобів контролю. Визначені чинники, що впливають на зниження ефективності процесу передачі електроенергії електричною мережею. Проведено дослідження моніторингу параметрів трансформатора засобами установки вимірювальних комплексів як з боку високої напруги так і з боку низької напруги. За виміряними даними побудований графік втрат в трансформаторі. Розроблені алгоритми на основі даних моніторингу і їх застосування на практиці для підвищення ефективності передачі електроенергії мережею.
In qualifying work of master's degree development of technical measures is carried out it is Set in relation to optimization of the system of power supply of network of transformer substation of 110/10 кВ., that it is necessary to provide a network by 110/10 кВ facilities of RMON of parameters on all levels. The locations of controls given for places are got. Certain factors that influence on the decline of efficiency of process of transmission of electric power an electric network. Research of monitoring of parameters of transformer is conducted by facilities of setting of measuring complexes as from the side of high tension so from the side of low tension. From measured data the built chart of losses is in a transformer. Worked out algorithms on the basis of data of monitoring and their application in practice for the increase of efficiency of transmission of electric power by a network.
ЗМІСТ ВСТУП 6 1 АНАЛІТИЧНИЙ РОЗДІЛ 9 1.1 Аналіз високовольтної мережі підстанції 110/10 кВ 9 1.2 Аналіз мережі середньої напруги ПС 110/10 кВ 12 1.3 Аналіз мережі низької напруги ПС 110/10 кВ 16 1.4 Висновки до розділу 1 17 2 РОЗРАХУНКОВО-ДОСЛІДНИЦЬКИЙ РОЗДІЛ 18 2.1 Існуючі методи контролю параметрів мережі 18 2.2 Критичний аналіз існуючих методів контролю параметрів мережі 21 2.3 Контроль втрат в мережі 110/10/0,4 кВ 24 2.4 Контроль величини втрат в трансформаторі і лінії 36 2.5 Висновки до розділу 2 39 3 ПРОЕКТНО-КОНСТРУКТОРСЬКИЙ РОЗДІЛ 40 3.1 Застосування розрахунку втрат по методу оперативних даних 40 3.2 Компенсація реактивної потужності 43 3.3 Інтелектуальна система АЧР 46 3.4 Використання моніторингу при технологічному приєднанні 48 3.5 Алгоритм визначення нетехнічних втрат 51 3.6 Нерівномірне навантаження в мережах 220-380 В 60 3.7 Контроль показників якості електроенергії 60 3.8 Контроль температури приладів обліку 61 3.9 Висновки до розділу 3 62 5 4 ОХОРОНА ПРАЦІ ТА БЕЗПЕКА В НАДЗВИЧАЙНИХ СИТУАЦІЯХ 63 4.1 Безпека праці електромонтера по обслуговуванню трансформаторних підстанцій і розподільних пунктів 63 4.2 Принципи і заходи підвищення стійкості функціонування об'єктів економіки 67 ЗАГАЛЬНІ ВИСНОВКИ 70 ПЕРЕЛІК ПОСИЛАНЬ 72
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Sari, Huseyin. "Motion Estimation Using Complex Discrete Wavelet Transform." Master's thesis, METU, 2003. http://etd.lib.metu.edu.tr/upload/1223205/index.pdf.
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The estimation of optical flow has become a vital research field in image sequence
analysis especially in past two decades, which found applications in many fields such as
stereo optics, video compression, robotics and computer vision. In this thesis, the complex
wavelet based algorithm for the estimation of optical flow developed by Magarey and
Kingsbury is implemented and investigated.
The algorithm is based on a complex version of the discrete wavelet transform (CDWT),
which analyzes an image through blocks of filtering with a set of Gabor-like kernels with
different scales and orientations. The output is a hierarchy of scaled and subsampled
orientation-tuned subimages. The motion estimation algorithm is based on the relationship
between translations in image domain and phase shifts in CDWT domain, which is satisfied
by the shiftability and interpolability property of CDWT. Optical flow is estimated by using
this relationship at each scale, in a coarse-to-fine (hierarchical) manner, where information
from finer scales is used to refine the estimates from coarser scales.
The performance of the motion estimation algorithm is investigated with various image
sequences as input and the effects of the options in the algorithm like curvature-correction,
interpolation kernel between levels and some parameter values like confidence threshold
iv
maximum number of CDWT levels and minimum finest level of detail are also experimented
and discussed.
The test results show that the method is superior to other well-known algorithms in
estimation accuracy, especially under high illuminance variations and additive noise.
5
Yilmaz, Sener. "Generalized Area Tracking Using Complex Discrete Wavelet Transform: The Complex Wavelet Tracker." Phd thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/3/12608643/index.pdf.
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In this work, a new method is proposed that can be used for area tracking. This method is based on the Complex Discrete Wavelet Transform (CDWT) developed by Magarey and Kingsbury. The CDWT has its advantages over the traditional Discrete Wavelet Transform such as approximate shift invariance, improved directional selectivity, and robustness to noise and illumination changes.
The proposed method is a generalization of the CDWT based motion estimation method developed by Magarey and Kingsbury. The Complex Wavelet Tracker extends the original method to estimate the true motion of regions according to a parametric motion model. In this way, rotation, scaling, and shear type of motions can be handled in addition to pure translation.
Simulations have been performed on the proposed method including both quantitative and qualitative tests. Quantitative tests are performed on synthetically created test sequences and results have been compared to true data. The performance is compared with intensity-based methods. Qualitative tests are performed on real sequences and evaluations are presented empirically. The results are compared with intensity-based methods.
It is observed that the proposed method is very accurate in handling affine deformations for long term sequences and is robust to different target signatures and illumination changes. The accuracy of the proposed method is compatible with intensity-based methods. In addition to this, it can handle a wider range of cases and is robust to illuminaton changes compared to intensity-based methods.
The method can be implemented in real-time and could be a powerful replacement of current area trackers.
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Ferreira, Rafael Fransak. "Filogenia do Complexo Drosophila Buzzatii (Grupo Repleta): Inferências de Análises Multilocus Mitocondriais e Nucleares." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/17/17135/tde-26092011-154314/.
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O complexo Drosophila buzzatii (grupo repleta) compreende 13 espécies, divididas em três clusters, de acordo com o bandeamento observado nos cromossomos politênicos: cluster D. stalkeri, incluindo D. richardsoni e D. stalkeri, restrito às ilhas do Caribe e Flórida; cluster D. martensis, incluindo D. martensis, D. uniseta, D. venezolana e D. starmeri, encontrado em áreas desérticas da Colômbia e Venezuela; e cluster D. buzzatii, incluindo D. buzzatii, D. koepferae, D. antonietae, D. serido, D. gouveai, D. borborema e D. seriema, habitando regiões sazonalmente secas ao longo da diagonal de vegetação aberta da América do Sul. O presente estudo teve como objetivo inferir as relações filogenéticas entre as espécies do complexo D. buzzatii, dando ênfase ao cluster D. buzzatii, por meio de análises multilocus de genes mitocondriais (COI e COII) e nucleares (EF-1F1, transformer e period). Nas hipóteses filogenéticas estabelecidas, as espécies do complexo D. buzzatii constituíram um grupo monofilético, composto por dois subgrupos monofiléticos, os clusters D. martensis e D. buzzatii, e um parafilético, o cluster D. stalkeri. As relações de parentesco entre as espécies do cluster D. buzzatii foram estabelecidas. Drosophila buzzatii ocupou a posição mais basal dentro do cluster D. buzzatii, estando proximamente relacionada à espécie D. koepferae. Drosophila antonietae ocupou uma posição intermediária em relação às espécies D. koepferae e D. serido, que representa o táxon irmão do ramo formado por D. gouveai, D. borborema e D. seriema, com D. gouveai ocupando uma posição mais basal em relação às espécies irmãs D. borborema e D. seriema. Foi detectada seleção purificadora como a principal força dirigindo a evolução dos genes nucleares transformer e period, para as espécies do complexo D. buzzatii. O gene mitocondrial COI, por sua vez, foi utilizado para estimar os tempos de divergência para as espécies do cluster D. buzzatii, revelando que o processo de diversificação do grupo iniciou-se no período Plioceno, provavelmente em decorrência de eventos de vicariância associados à elevação dos Andes, sendo também influenciado pelo avanço e retração da vegetação xerófita, nas flutuações climáticas do Pleistoceno.Drosophila buzzatii complex (repleta group) consists of 13 species, divided into three clusters according to the banding seen in polytene chromosomes: D. stalkeri cluster, including D. richardsoni and D. stalkeri, restricted to the Caribbean Islands and Florida; D. martensis cluster, including D. martensis, D. uniseta, D. venezuelana and D. starmeri, found in desert areas of Colombia and Venezuela, and D. buzzatii cluster, including D. buzzatii, D. koepferae, D. antonietae, D.gouveai, D. borborema and D. seriema, that inhabit seasonally dry regions along the open vegetation diagonal in South America. This study aimed to infer the phylogenetic relationships among the D. buzzatii species complex, emphasizing the D. buzzatii cluster, by multilocus analysis of mitochondrial (COI and COII) and nuclear (EF-1F1, transformer and period) genes. In established phylogenetic hypotheises, the species of the D. buzzatii complex formed a monophyletic group, composed of two monophyletic subgroups, the D. martensis and D. buzzatii clusters, and a paraphyletic one, the D. stalkeri cluster. The relationships among the D. buzzatii species cluster were established. Drosophila buzzatii occupied the most basal position within the D. buzzatii cluster and is closely related to D. koepferae. D. antonietae occupied an intermediate position in relation to the D. koepferae and D. serido species. D. serido represents the sister taxon of the branch formed by the D. gouveai, D. borborema and D. seriema species, with D. gouveai occupying a basal position in relation to the sister species D. borborema and D. seriema. It was detected that purifying selection is the main force driving the evolution of transformer and period nuclear genes for the species of the D. buzzatii complex. The divergence time of the D. buzzatii species cluster was estimated by the COI gene analysis, revealing that the process of diversification of the group began in the Pliocene period, probably due to vicariant events associated with the uplift phase of the Andes, and it was also influenced by the advance and retraction of xerophytic vegetation in Pleistocene climatic fluctuations.
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Daza, Enrique Acha. "Modelling of power system transformers in the complex conjugate harmonic space." Thesis, University of Canterbury. Electrical Engineering, 1988. http://hdl.handle.net/10092/5450.
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Magnetizing harmonics in power systems have received limited attention. The general belief is that they do not reach harmful levels in interconnected networks. Moreover the modelling of non-linearities is not a straightforward procedure and so there has been little motivation to develop appropriate methodologies that allow a thorough investigation to take place.
In this thesis the problem of magnetizing harmonics in power systems is investigated. The results obtained show that, contrary to expectations, magnetizing currents can give rise to a considerable harmonic distortion in the voltage wave form of power networks operating under loaded conditions.
The method adopted in this research linearizes each magnetic non-linearity around a base operating point. The linearization exercise takes place in the complex-conjugate harmonic space and the individual linearized equations may be interpreted as harmonic Norton equivalents. These equations combine easily with each other and with the transfer admittances representing the linear part of the network. The overall process of linearization may be seen as a linearization of the entire network and can also be interpreted as a multi-nodal, polyphase harmonic Norton equivalent.
This problem is non-linear and the harmonic solution is reached by an iterative process. A re-linearization of the network takes place at each iterative step and so the solution is found through a Newton-type procedure. Several iterative strategies are tested, including unified and sequential solutions with either single or multi-evaluated Jacobians.
A hitherto neglected problem which also receives attention is the harmonic modelling of non-homogenous transmission lines. A novel approach to the modelling of the frequency dependent part of the transmission line is also presented. The equations proposed are shown to be the fastest to date and yet maintain a high degree of accuracy.
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Casseli, Irène. "Eléments sur la transformée de Berezin et sur les opérateurs de Toeplitz dans des espaces de fonctions polyanalytiques." Thesis, Aix-Marseille, 2019. http://www.theses.fr/2019AIXM0578.
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Les fonctions polyanalytiques entières généralisent les fonctions entières dans la mesure où elles sont les solutions sur le plan complexe \mathbb{C} de l'équation de Cauchy-Riemann à l'ordre n, de la forme { partial} nf / \partial \overline{z} n = 0. Un espace de Fock polyanalytique F2 {\alpha,n} est, par analogie avec le cas classique, le sous-espace fermé de l'espace de Hilbert L^2 (\mathbb{C},d\mu \alpha), où \mu \alpha est une mesure de probabilité gaussienne sur \mathbb{C} de paramètre alpha>0, formé des fonctions polyanalytiques entières d'ordre n. L'objet de cette thèses est l'étude d'éléments classiques de la théorie des opérateurs tels que la transformée de Berezin et les opérateurs de Toeplitz dans le cadre particulier des espaces de Fock polyanalytiques. Dans ce manuscrit, il est montré en particulier que les points fixes de la transformée de Berezin qui appartiennent aux espaces de Lebesgue sont les fonctions nulles ou éventuellement constantes. Concernant les opérateurs de Toeplitz, le problème de Sarason est étudié. Etant donné une fonction f, l'opérateur de Toeplitz de symbole f est formellement défini par T {alpha,n} f(h)=P {alpha,n}(f h), où P {alpha,n} est la projection orthogonale de L^2(\mathbb{C},d\mu {alpha}) sur F^2 {alpha,n}. Le problème de Sarason consiste à donner une condition nécessaire et suffisante sur f et g pour que le produit d'opérateurs de symboles f et bar g soit continuEntire polyanalytic functions generalize entire functions in that they are solutions of "Cauchy-Riemann equations of order n, of the form {\partial}^n f / \partial \overline{z}^n = 0, over the whole complex plane \mathbb{C}. Polyanalytic Fock space F^2_{\alpha,n} is, by analogy with the classical case, the closed subspace of the Hilbert space L^2(\mathbb{C},d\mu_\alpha), where \mu_\alpha is a Gaussian probability measure over \mathbb{C} with weight \alpha>0, of polyentire functions of order n. The aim of this PhD thesis is the study of classical objects of operator theory such that the Berezin transform and Toeplitz operators in the particular case of polyanalytic Fock spaces. In this written, it is shown among other results, that the L^p fixed points of the Berezin transform are constant functions. Concerning Toeplitz operators, the Sarason problem is studied. Given a function f, the Toeplitz operator with symbol f is formally defined by T^n_f(h)=P_{F^2_n}(f h), where P_{F^2_n} is the orthogonal projection from L^2(\mathbb{C},d\mu) on to F^2_n. The so-called Sarason's problem consists in finding necessary and sufficient conditions on the symbols f and g for the Toeplitz product with symbols f and \bar g to be bounded in the Fock space
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Thornton, A. L. "Colour object recognition using a complex colour representation and the frequency domain." Thesis, University of Reading, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.301911.
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Reeves, Tanya Heather. "Overcomplete image coding using the dual-tree complex wavelet transform." Thesis, University of Cambridge, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.615767.
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Kennel, Pol. "Caractérisation de texture par analyse en ondelettes complexes pour la segmentation d’image : applications en télédétection et en écologie forestière." Thesis, Montpellier 2, 2013. http://www.theses.fr/2013MON20215/document.
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L'analyse des images numériques, bien que largement étudiée, reste encore aujourd'hui un réel défi. Avec pour objectifs la description pertinente et la reconnaissance sémantique du contenu de celles-ci, de nombreuses applications requièrent une attention particulière quant à cette analyse. Pour répondre à ces besoins, l'analyse du contenu des images est réalisée de façon automatique grâce à des méthodes informatiques se rapprochant par exemple des mathématiques, des statistiques, de la physique. Une façon pertinente et reconnue de représenter les objets observés dans les images réside dans leur segmentation. Couplée à la classification, la segmentation permet une ségrégation sémantique de ces objets. Cependant, les méthodes existantes ne peuvent être considérées comme génériques, et bien que motivées par de nombreux domaines (militaire, médical, satellite, etc.), celles-ci sont continuellement réévaluées, adaptées et améliorées. Par exemple, les images satellites se démarquent dans le milieu de l'image de par leur spécificité d'acquisition, de par leur support ou de par le sujet d'observation (la Terre dans notre cas).Cette thèse à pour but d'explorer les méthodes de caractérisation et de segmentation supervisées exploitant la notion de texture. Les sols observés depuis l'espace, à des échelles et des résolutions différentes, peuvent être perçus comme texturés. Les cartes d'occupation des sols peuvent être obtenues par la segmentation d'images satellites, notamment en utilisant l'information texturale. Nous proposons le développement d'algorithmes de segmentation compétitifs caractérisant la texture par l'utilisation de représentations multi-échelles des images obtenues par décomposition en ondelettes et de classificateurs supervisés tels que les Support Vector Machines. Dans cette optique, cette thèse est principalement articulée autour de plusieurs projets de recherche nécessitant une étude des images à des échelles et des résolutions différentes, ces images étant elles-mêmes de nature variée (e.g. multi-spectrales, optiques, LiDAR). Nous dériverons, pour ces différents cas d'étude, certains aspects de la méthodologie développéeThe analysis of digital images, albeit widely researched, continues to present a real challenge today. In the case of several applications which aim to produce an appropriate description and semantic recognition of image content, particular attention is required to be given to image analysis. In response to such requirements, image content analysis is carried out automatically with the help of computational methods that tend towards the domains of mathematics, statistics and physics. The use of image segmentation methods is a relevant and recognized way to represent objects observed in images. Coupled with classification, segmentation allows a semantic segregation of these objects. However, existing methods cannot be considered to be generic, and despite having been inspired by various domains (military, medical, satellite etc), they are continuously subject to reevaluation, adaptation or improvement. For example satellite images stand out in the image domain in terms of the specificity of their mode of acquisition, their format, or the object of observation (the Earth, in this case).The aim of the present thesis is to explore, by exploiting the notion of texture, methods of digital image characterization and supervised segmentation. Land, observed from space at different scales and resolutions, could be perceived as being textured. Land-use maps could be obtained through the segmentation of satellite images, in particular through the use of textural information. We propose to develop competitive algorithms of segmentation to characterize texture, using multi-scale representations of images obtained by wavelet decomposition and supervised classifiers such as Support Vector Machines.Given this context, the present thesis is principally articulated around various research projects which require the study of images at different scales and resolutions, and which are varying in nature (eg. multi-spectral, optic, LiDAR). Certain aspects of the methodology developed are applied to the different case studies undertaken
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Pillet, Basile. "Géométrie complexe globale et infinitésimale de l'espace des twisteurs d'une variété hyperkählérienne." Thesis, Rennes 1, 2017. http://www.theses.fr/2017REN1S021/document.
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L'objet de cette thèse est la construction d'objets géométriques sur une variété C paramétrant des courbes rationnelles dans l'espace des twisteurs d'une variété hyperkählérienne. On établira une correspondance entre la géométrie complexe de l'espace des twisteurs et des propriétés différentielles sur C (opérateurs différentiels et courbure de la structure riemanienne complexe héritée de la variété hyperkählérienne). Les premiers chapitres précisent le cadre et les résultats connus. Dans les chapitres 4, 5 et 6 on établit une équivalence de catégories entre fibrés triviaux en restriction à chaque droite de l'espace des twisteurs et les fibrés à connexion sur C satisfaisant une condition de courbure. Le chapitre 7 prolonge cette correspondance sur le plan cohomologique tandis que le chapitre 8 en fait l'étude infinitésimale en reliant la courbure de la connexion avec les épaississements infinitésimaux des fibrés le long des droitesThe purpose of this thesis is to construct geometric objects on a manifold C parametrizing rational curves in the twistor space of a hyperkähler manifold. We shall establish a correspondence between the complex geometry of the twistor space and some differential properties of C (differential operators and curvature of a complex riemannian structure inherited from the base hyperkähler manifold). The first chapters gather some classical results of the theory of hyperkähler manifolds and their twistor spaces. In the chapters 4, 5 and 6, we construct an equivalence of categories between bundles on the twistor space which are trivial on each line and bundles with a connexion of C satisfying certain curvature conditions. The chapter 7 extends this correspondence on the cohomological level whereas the chapter 8 explores its infinitesimal version ; it links curvature of the connexion with thickening (in the sense of LeBrun) of the bundle along the lines
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Wörmke, Stephan. "Fourier transform microwave studies of small molecules and molecular complexes : measurements on HD¹²C¹⁶O, on 2-methylpyridine and its complex with Argon /." Stockholm, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4075.
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Schwab, Lukas [Verfasser], and M. [Akademischer Betreuer] Wilhelm. "Fourier transform rheology of complex, filled rubber materials / Lukas Schwab. Betreuer: M. Wilhelm." Karlsruhe : KIT-Bibliothek, 2016. http://d-nb.info/1095665413/34.
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Wong, Wilson W. K. (Wilson Wai Keung) Carleton University Dissertation Engineering Electrical. "A fast fourier transform radix-2 complex butterfly with built-in self-test." Ottawa, 1992.
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Chagnon-Lessard, Sophie. "Cellular Responses to Complex Strain Fields Studied in Microfluidic Devices." Thesis, Université d'Ottawa / University of Ottawa, 2018. http://hdl.handle.net/10393/37915.
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Cells in living organisms are constantly experiencing a variety of mechanical cues. From the stiffness of the extra cellular matrix to its topography, not to mention the presence of shear stress and tension, the physical characteristics of the microenvironment shape the cells’ fate. A rapidly growing body of work shows that cellular responses to these stimuli constitute regulatory mechanisms in many fundamental biological functions. Substrate strains were previously shown to be sensed by cells and activate diverse biochemical signaling pathways, leading to major remodeling and reorganization of cellular structures. The majority of studies had focused on the stretching avoidance response in near-uniform strain fields. Prior to this work, the cellular responses to complex planar strain fields were largely unknown. In this thesis, we uncover various aspects of strain sensing and response by first developing a tailored lab-on-a-chip platform that mimics the non-uniformity and complexity of physiological strains. These microfluidic cell stretchers allow independent biaxial control, generate cyclic stretching profiles with biologically relevant strain and strain gradient amplitudes, and enable high resolution imaging of on-chip cell cultures. Using these microdevices, we reveal that strain gradients are potent mechanical cues by uncovering the phenomenon of cell gradient avoidance. This work establishes that the cellular mechanosensing machinery can sense and localize changes in strain amplitude, which orchestrate a coordinated cellular response. Subsequently, we investigate the effect of multiple changes in stretching directions to further explore mechanosensing subtleties. The evolution of the cellular response shed light on the interplay of the strain avoidance and the newly demonstrated strain gradient avoidance, which were found to occur on two different time scales. Finally, we extend our work to study the influence of cyclic strains on the early stages of cancer development in epithelial tissues (using MDCK-RasV12 system), which was previously largely unexplored. This work reveals that external mechanical forces impede the healthy cells’ ability to eliminate newly transformed cells and greatly promote invasive protrusions, as a result of their different mechanoresponsiveness. Overall, not only does our work reveal new insights regarding the long-range organization in population of cells, but it may also contribute to paving the way towards new approaches in cancer prevention treatments.
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Lane, Pierre M. "The complex-valued optical Fourier transform and its application to moving-object trajectory estimation." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0017/NQ48296.pdf.
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Smith, Kimberley Hazel. "Fast Fourier transform and dynamic imaging of caveolar complex arrays in active striated muscle." Thesis, University of Leicester, 2010. http://hdl.handle.net/2381/8767.
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Appendix 2: Movie Clips is supplied as a Zip Archive and will need to be unzipped before viewing. The mechanism of force transfer from contracting sarcomeres to the membrane and endomysium of striated muscle fibres is unclear. The caveolar complex array in striated muscle membranes is a local concentration of cholesterol, sphingomyelin, signalling molecules and the protein caveolin-3. Immunofluorescence microscopy of caveolin-3 in the membrane reveals a regular pattern of fluorescent nodes arranged in longitudinal and transverse rows. The primary aim of this study was to analyse this pattern and how caveolin-3 behaves during contraction. Dynamic imaging and Fast Fourier Transforms (FFTs) were used to study force transmission across the fibre membrane. This pattern was studied in frozen sections of both shortened and rest-length striated muscle fibres. Direct and FFT measurements of spacings between these nodes demonstrated significant reductions in longitudinal measurements in shortened muscle when compared to rest-length muscle. Caveolin-3 nodes lay in register with underlying actin bands in both muscle states, and co-localised with dystrophin. Caveolin-3 was not detectable in C2C12 myoblasts. During differentiation expression became detectable at 2 days. Caveolin-3 was present during myoblast fusion, before forming the regular pattern on the membrane from days 4-5. Fibres became contractile after 5-6 days of development. By 12 days, muscle fibres are 1-2 mm long, multinucleated myotubes with evidence of the caveolin-3 immunofluorescence pattern seen in mature fibres. Knockdown of caveolin-3 expression greatly reduced the number of differentiated myotubes at 12 days. This pattern was not demonstrated in contracting myotubes, possibly owing to lack of permeability to the antibody. The results are consistent with the hypothesis that the force of contraction is transferred across the whole membrane rather than at fibre distal ends.
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Fink, Michael Charles. "Molecular Fourier imaging correlation spectroscopy for studies of molecular diffusion /." view abstract or download file of text, 2006. http://wwwlib.umi.com/cr/uoregon/fullcit?p3211214.
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Thesis (Ph. D.)--University of Oregon, 2006.Typescript. Includes vita and abstract. Includes bibliographical references (leaves 104-111). Also available for download via the World Wide Web; free to University of Oregon users.
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Ramström, Margareta. "Analysis of Complex Biological Samples using Liquid Chromatography-Fourier Transform Ion Cyclotron Resonance Mass Spectrometry." Doctoral thesis, Uppsala University, Analytical Chemistry, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-5729.
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Studies of protein and peptide expression are vital in order to understand complex biological systems. As demonstrated in this thesis, on-line packed capillary liquid chromatography-Fourier transform ion cyclotron resonance mass spectrometry (LC-FTICR MS) is a useful analytical tool for such studies.
A proteomics method, based on global tryptic digestion and subsequent separation and detection of the peptides by LC-FTICR MS, was developed for qualitative analysis of body fluids. Initial experiments on cerebrospinal fluid (CSF) provided results that were comparable or superior to those achieved by more time- and sample-consuming techniques. The method was also successfully applied on plasma and amniotic fluid. One of the major challenges in proteomics is the broad dynamic range of proteins in biological matrices. The advantages of removing high-abundant components from CSF and plasma prior to MS were demonstrated.
In order to search for potential biomarkers, mass chromatograms of CSF from patients suffering from amyotrophic lateral sclerosis (ALS) and controls were compared using an in-house constructed pattern recognition program. ALS-specific patterns were observed, and four out of five unknown samples were correctly assigned. Alternative strategies to quantitatively compare two pools of samples rely on differential chemical labeling. The performance of one such method, quantification-using-enhanced-signal-tags, was investigated in complex sample analysis. The experimental intensity ratios were proven to be consistent with the prepared concentration ratios of abundant proteins in CSF.
Finally, the thesis reports on the first experiments where electron capture dissociation (ECD) was successfully incorporated in on-line LC-MS experiments. ECD and nozzle-skimmer fragmentation were applied to a sample of endocrine peptides extracted from mouse pancreatic islets. The two fragmentation methods provided complementary information. However, the method needs further optimization before it can be applied in the analysis of more complex samples, such as body fluids.
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Tse, Chung Fai Norman. "The development of complex continuous wavelet transform based harmonic analysis and dynamic waveform reconstruction algorithms." Thesis, City University London, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.446448.
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Castellano, Gabriela. "Investigation and application of a complex wavelet transform algorithm for the estimation of optical flow." Thesis, King's College London (University of London), 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.391765.
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Serafin, Michal M. "Fourier-transform microwave spectroscopy of cyclopropylmethylgermane and van der Waals complexes of fluorinated methanes /." View online, 2008. http://repository.eiu.edu/theses/docs/32211131400051.pdf.
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Betah, Mohamed Haye. "Un théorème de Gallagher pour la fonction de Möbius." Thesis, Aix-Marseille, 2018. http://www.theses.fr/2018AIXM0461/document.
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La fonction de Möbius est définie par$$\mu(n)= \begin{cases} 1 & \textit{si $n=1$},\\ (-1)^k& \textit{si n est le produit de k nombres premiers distincts,}\\ 0 & \textit{si n contient un facteur carré. } \end{cases}$$Nous avons démontré que pour $x \ge \exp( 10^9) $ et $h=x^{1-\frac{1}{16000}}$, il existe dans chaque intervalle $[x-h,x]$ des entiers $n_1$ avec $\mu(n_1)=1$ et des entiers $n_2$ avec $\mu(n_2)=-1$.\\Ce résultat est une conséquence d'un résultat plus général.\\Pour $x \ge \exp(4\times 10^6)$, $\frac{1}{\sqrt{\log x}} \le \theta \le \frac{1}{2000}$, $h=x^{1-\theta}$ et $Q=(x/h)^{\frac{1}{20}}$, nous avons \\$$\sum_{q \leq Q} \log(Q/q)\sum_{\chi mod q}^*\left| \sum_{x.-h\le n \le x} \mu(n) \chi(n) \right| \leq 10^{20} h \theta \log(x) \exp( \frac{-1}{300 \theta}); $$la somme $\sum^*$ portant sur les caractères primitifs sauf l'éventuel caractère exceptionnel.\\Et en particulier pour $x \ge \exp( 10^9)$,$$ \left | \sum_{x.-x^{1-\frac{1}{16000}}\le n \le x} \mu(n) \right | \le \frac{1}{100} x^{1-\frac{1}{16000}}.\\$$The Möbius function is defined by$$\mu(n)= \begin{cases} 1 & \textit{if $n=1$},\\ (-1)^k& \textit{if n is a product of k distinct prime numbers,}\\ 0 & \textit{if n contains a square factor. } \end{cases}$$We demonstrate that for $x \ge \exp( 10^9) $ and $h=x^{1-\frac{1}{16000}}$, it exists in each interval $[x-h,x]$ integers $n_1$ with $\mu(n_1)=1$ and integers $n_2$ with $\mu(n_2)=-1$.\\This result is a consequence of a more general result. \\For $x \ge \exp(4\times 10^6)$, $\frac{1}{\sqrt{\log x}} \le \theta \le \frac{1}{2000}$, $h=x^{1-\theta}$ et $Q=(x/h)^{\frac{1}{20}}$, we have \\ $$\sum_{q \leq Q} \log(Q/q)\sum_{\chi mod q}^*\left| \sum_{x-h \le n \le x} \mu(n) \chi(n) \right| \leq 10^{20} h \theta \log(x) \exp( \frac{-1}{300 \theta}); $$the sum $\sum^*$ relating to primitive characters except for possible exceptional character.\\And in particular for $x \ge \exp( 10^9)$,$$\left | \sum_{x-.x^{1-\frac{1}{16000}}\le n \le x} \mu(n) \right | \le \frac{1}{100} x^{1-\frac{1}{16000}}.$$
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Ami, Diletta. "Microspectroscopie infrarouge de systèmes biologiques complexes." Reims, 2004. http://www.theses.fr/2004REIMP201.
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Les @travaux de recherche présentés dans cette thèse décrivent l'application de la microscopie infrarouge à transformée de Fourier (MIRTF) à l'étude de systèmes biologiques complexes. Outre l'étude par IRTF de micro-organismes d'intérêt clinique tels que Candida et E. Coli appartenant à différentes souches, un regard particulier a été porté sur la potentialité de la microscopie IRTF en biotechnologie. Notamment, l'agrégation in situ de protéines en tant que corps d'inclusion chez E. Coli a été étudiée dans le but de suivre l'expression de protéines hétérologues dans des cellules intactes afin d'identifier la souche qui surexprime ces protéines. De plus, une étude préliminaire chez le nématode C. Elegans - un modèle important en biotechnologie - a été effectuée par microscopie IRTF. Cette étude a permis la discrimination de nématodes appartenant à différents taxons en accord avec la méthode de classification basée sur des techniques de biologie moléculaire - un résultat qui est d'un intérêt croissant dans le domaine des sciences environnementales, agronomiques et cliniques@In this thesis the application of FT-IR microspectroscopy to the study of complex biological systems has been studied. In addition to the FT-IR studies of microorganisms of clinical interest such as Candida and E. Coli belonging to different strains, in this thesis emphasis has been laid on the power of FT-IR microspectroscopy in biotechnology. In particular, the aggregation of proteins in situ in E. Coli cells as inclusion bodies has been studied with the aim of monitoring the expression of heterologous proteins in intact cells in order to identify the most expressing strain. Furthermore, a preliminary absorption study on the nematode C. Elegans - an important model system in biotechnology - has been performed by FT-IR microspectroscopy. This study has allowed the discrimination of nematodes belonging to different taxa in agreement with classification method based on molecular biology - a result which is of growing interest in environmental, agriculture and clinical sciences
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Bernardes, Alexandre Paciencia. "Um esquema completo de proteção diferencial de transformadores para testes em um relé digital." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/18/18154/tde-16072006-122259/.
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Este trabalho apresenta um procedimento completo de simulação da proteção digital diferencial aplicada a transformadores de potência, visando o emprego deste à avaliação do comportamento de relés comercialmente disponíveis. Foi escolhido o software ATP (Alternative Transients Program) como ferramenta para a simulação de distintas situações sobre um sistema diferencial de proteção aplicado a um transformador de 25 MVA. Dentre as ocorrências evidenciadas, destacam-se: situações de faltas internas, faltas externas, situações de energização e energização com falta interna do transformador, condição de sobreexcitação e de saturação de TC (Transformador de Corrente). Cabe comentar que das simulações a real caracterização sobre o relé em teste, fez-se necessário todo um pré-processamento e análise da informação que será convenientemente abordada e justificada no trabalho apresentado, denotando-se um procedimento comum de teste a ser adotado a esta filosofia de proteção. A metodologia e esquema prático adotado trazem uma contribuição importante para a análise laboratorial de modelagens e simulações aplicadas a relés de proteção presentes no mercado e contribui de maneira substancial para os estudos teóricos de possíveis soluções para limitações eventualmente encontradasThis dissertation presents a complete procedure of simulation of digital differential protection applied to power transformers, focusing on its use to evaluate of the behavior of commercially available relays. Software ATP (Alternative Transients Program) was chosen as a tool for the simulation of distinct situations in a differential protection system applied to a 25 MVA three-phase transformer. Amongst the evidenced occurrences internal and external fault conditions, energization with or without internal fault of a three-phase transformer, overexcitation and CT (Current Transformer) saturation conditions were distinguished. It should be mentioned that from simulations to the characterization the real situations on the relay in test, a pre-processing and analysis of the information were necessary, and will be justified in the present study, denoting a common test procedure to be adopted to this philosophy of protection
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Bowlyn, Kevin Nathaniel. "IMPLEMENTATION OF A NOVEL INTEGRATED DISTRIBUTED ARITHMETIC AND COMPLEX BINARY NUMBER SYSTEM IN FAST FOURIER TRANSFORM ALGORITHM." OpenSIUC, 2017. https://opensiuc.lib.siu.edu/dissertations/1470.
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This research focuses on a novel integrated approach for computing and representing complex numbers as a single entity without the use of any dedicated multiplier for calculating the fast Fourier transform algorithm (FFT), using the Distributed Arithmetic (DA) technique and Complex Binary Number Systems (CBNS). The FFT algorithm is one of the most used and implemented technique employed in many Digital Signal Processing (DSP) applications in the field of science, engineering, and mathematics. The DA approach is a technique that is used to compute the inner dot product between two vectors without the use of any dedicated multipliers. These dedicated multipliers are fast but they consume a large amount of hardware and are quite costly. The DA multiplier process is accomplished by shifting and adding only without the need of any dedicated multiplier. In today's technology, complex numbers are computed using the divide and conquer approach in which complex numbers are divided into two parts: the real and imaginary. The CBNS technique however, allows for each complex addition and multiplication to be computed in one single step instead of two. With the combined DA-CBNS approach for computing the FFT algorithm, those dedicated multipliers are being replaced with a DA system that utilize a Rom-based memory for storing the twiddle factor 'wn' value and the complex arithmetic operations being represented as a single entity, not two, with the CBNS approach. This architectural design was implemented by coding in a very high speed integrated circuit (VHSIC) hardware description language (VHDL) using Xilinx ISE design suite software program version 14.2. This computer aided tool allows for the design to be synthesized to a logic gate level in order to be further implemented onto a Field Programmable Gate Array (FPGA) device. The VHDL code used to build this architecture was downloaded on a Nexys 4 DDR Artix-7 FPGA board for further testing and analysis. This novel technique resulted in the use of no dedicated multipliers and required half the amount of complex arithmetic computations needed for calculating an FFT structure compared with its current traditional approach. Finally, the results showed that for the proposed architecture design, for a 32 bit, 8-point DA-CBNS FFT structure, the results showed a 32% area reduction, 41% power reduction, 59% reduction in run-time, 42% reduction in logic gate cost, and 66% increase in speed. For a 28 bit, 16-point DA-CBNS FFT structure, its area size, power consumption, run-time, and logic gate, were also found to be reduced at approximately 30%, 37%, 60%, and 39%, respectively, with an increase of speed of approximately 67% when compared to the traditional approach that employs dedicated multipliers and computes its complex arithmetic as two separate entities: the real and imaginary.
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Abreu, Caio Cesar Enside de [UNESP]. "Melhoramento de sinais de voz baseado na identificação de padrões ruidosos." Universidade Estadual Paulista (UNESP), 2017. http://hdl.handle.net/11449/149986.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Este trabalho propõe contribuir com pesquisas em melhoramento de voz (MV) por meio do estudo de diversos tipos de algoritmos baseados em Fourier e wavelets, assim como o desenvolvimento de uma ferramenta para a identificação e classificação do ruído, culminando com uma nova metodologia. Denominada "Conjunto de Métodos de Melhoramento de Voz (CMMV)'', a metodologia consiste em utilizar um banco de dados com sentenças contaminadas com vários tipos de ruídos reais, ajustando, em modo off-line, vários métodos de MV para cada tipo de ruído. Os melhores métodos para cada tipo de ruído são selecionados para compor o conjunto de métodos. Durante a operação, em modo on-line, um classificador de ruído prediz o tipo de ruído presente no sinal em processamento e então o melhor método é escolhido dentro do CMMV construído. Seis tipos de ruídos foram utilizados durante as simulações e os métodos que obtiveram melhor desempenho frente a cada tipo foram indicados por meio de análise objetiva. Constatou-se que o desempenho desses métodos pode variar de acordo com o tipo do ruído de fundo, confirmando que o desenvolvimento de algoritmos que trabalham eficientemente em qualquer ambiente ruidoso, incorporando classificação de ruído, é uma tendência. O classificador de ruídos desenvolvido nesta pesquisa tem como base um sistema imunológico artificial e características extraídas por uma análise multiescala fornecida pela transformada wavelet complexa. Com uma acurácia média de 96,29% para os seis tipos de ruído considerados e tempo de resposta médio de 6,9 milissegundos, o classificador desenvolvido se mostrou viável para implementações e utilização em conjunto com outras tecnologias. Explorando algumas das possibilidades e benefícios do processamento baseado na classificação do ruído, a seguinte questão foi levantada: "seria possível realizar uma razoável estimação do ruído a partir do sinal de voz ruidoso por meio de regressão?”. Esta questão surgiu durante o desenvolvimento da pesquisa, pois o bom funcionamento de métodos de MV depende de uma boa estimação do perfil do ruído. As simulações mostram que este tipo de estimação de ruído pode gerar resultados satisfatórios com menor custo computacional. Por fim, comparado aos métodos clássicos, o CMMV mostrou-se tão ou mais eficiente quanto.
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Abreu, Caio Cesar Enside de. "Melhoramento de sinais de voz baseado na identificação de padrões ruidosos /." Ilha Solteira, 2017. http://hdl.handle.net/11449/149986.
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Orientador: Francisco Villarreal AlvaradoResumo: Este trabalho propõe contribuir com pesquisas em melhoramento de voz (MV) por meio do estudo de diversos tipos de algoritmos baseados em Fourier e wavelets, assim como o desenvolvimento de uma ferramenta para a identificação e classificação do ruído, culminando com uma nova metodologia. Denominada "Conjunto de Métodos de Melhoramento de Voz (CMMV)'', a metodologia consiste em utilizar um banco de dados com sentenças contaminadas com vários tipos de ruídos reais, ajustando, em modo off-line, vários métodos de MV para cada tipo de ruído. Os melhores métodos para cada tipo de ruído são selecionados para compor o conjunto de métodos. Durante a operação, em modo on-line, um classificador de ruído prediz o tipo de ruído presente no sinal em processamento e então o melhor método é escolhido dentro do CMMV construído. Seis tipos de ruídos foram utilizados durante as simulações e os métodos que obtiveram melhor desempenho frente a cada tipo foram indicados por meio de análise objetiva. Constatou-se que o desempenho desses métodos pode variar de acordo com o tipo do ruído de fundo, confirmando que o desenvolvimento de algoritmos que trabalham eficientemente em qualquer ambiente ruidoso, incorporando classificação de ruído, é uma tendência. O classificador de ruídos desenvolvido nesta pesquisa tem como base um sistema imunológico artificial e características extraídas por uma análise multiescala fornecida pela transformada wavelet complexa. Com uma acurácia média de 96,29% para os seis... (Resumo completo, clicar acesso eletrônico abaixo)
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Anupriya, Anupriya. "Gas Phase Structure Characterization Using Fourier Transform Ion Cyclotron Resonance Mass Spectrometry." BYU ScholarsArchive, 2016. https://scholarsarchive.byu.edu/etd/6447.
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This dissertation investigates Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS) based techniques to study the impact of molecular structure on conformation and binding energetics. A novel method to determine collison cross sectional areas using FTICR (CRAFTI), initially developed by the Dearden lab, was applied to study the conformations of molecular systems with unique structural attributes in an attempt to explore the molecular range of CRAFTI. The systems chosen for CRAFTI studies include crown-ether alkylammonium complexes and biogenic amino acids. The results were found to be consistent with expected behavior, and strongly correlated with experimental measurements made using ion mobility spectrometry (IMS) and predictions from computations. The analytical sensitivity of CRAFTI was highlighted by its ability to distinguish the normal and branched structural isomers of butylamine. Besides conformation characterization, quantitative evaluation of binding was undertaken on metal ion-cryptand complexes on the FTICR instrument using sustained off-resonance irradiation-collision-induced dissociation (SORI CID) method. Complex formation and dissociation was found to be a strong function of both guest and host sizes which impacted steric selectivity, and polarizability. The results demonstrate the ability of FTICR to simultaneously determine structure, conformation and binding thereby providing comprehensive molecular characterization.
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Rouleau, Caroline. "Implications du pyruvate dans le métabolisme de lignées astrocytaires spinales spontanément transformées." Montpellier 1, 2006. http://www.theses.fr/2006MON1T029.
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L'objectif de ce travail est d'explorer en détail le métabolisme de lignées astrocytaires dérivant de la moelle épinière d'embryons de rat. La respiration mitochondriale, certains paramètres de la glycolyse et l'activité de l'oncogène Akt sont étudiés dans les lignées en passages précoces (EP) et dans les lignées en passages tardifs (LP), qui se sont spontanément transformées après avoir été maintenues pendant plus de 35 passages dans le milieu de culture ne contenant pas de pyruvate. Dans les LP, en comparaison avec les EP, il existe une diminution de la glycolyse, une réduction du nombre de mitochondries par cellule et un déficit de la respiration portant sur les complexes I et II+III de la chaîne respiratoire mitochondriale. Le traitement des LP par le pyruvate, pendant 20 passages supplémentaires, ne modifie pas l'état de transformation des cellules. Alors que ce traitement rétablit la glycolyse, aucun effet bénéfique n'est constaté sur le déficit respiratoire. Le traitement des EP par du pyruvate, jusqu'à ce qu'elles soient par définition en passages tardifs, prévient la transformation spontanée. Alors que les EP traitées par le pyruvate ont un déficit modéré de la respiration, elles renferment 2 fois plus de mitochondries par cellule que les EP non traitées. L'augmentation du nombre de mitochondries compense le déficit modéré de la respiration afin de maintenir les capacités d'oxydation dans ces lignées tardives qui ne sont pas transformées. Dans l'ensemble des lignées, l'activité de l'oncogène Akt varie dans le même sens que la glycolyse et que la respiration et est directement stimulée par le pyruvate dans les lignées traitées. En conclusion, ce travail ouvre de nouvelles perspectives quant à la compréhension des mécanismes possiblement associés à la transformation astrocytaire et met en évidence de nouvelles voies thérapeutiques potentielles afin d'améliorer le contrôle des proliférations astrocytaires.
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Oliveira, Francisco Ivan de. "Transformada de Hilbert Sobre Bases de Wavelets: DetecÃÃo de Complexos QRS." Universidade Federal do CearÃ, 2007. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=8599.
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nÃo hÃA tarefa mais importante em processamento de sinais de eletrocardiograma (ECG) à a determinaÃÃo exata do complexo de QRS, em particular, a detecÃÃo dos picos de onda R atravÃs de sistemas e anÃlises computadorizadas. à essencial, especialmente, para uma medida correta da variabilidade do ritmo cardÃaco (HRV). Um grande obstÃculo a ser superado para uma detecÃÃo confiÃvel à a sensibilidade do eletrocardiograma a diversas fontes de distÃrbio, tais como, a interferÃncia à rede elÃtrica, os artefatos do movimento, flutuaÃÃo da linha base e o ruÃdo dos mÃsculos. Este trabalho utiliza as propriedades matemÃticas da transformaÃÃo de Hilbert sobre wavelets para desenvolver um novo algoritmo capaz de diferenciar as ondas R das demais (P, Q, S, T e U) e facilitar a detecÃÃo dos complexos QRS. Uma taxa de detecÃÃo do complexo QRS de 99,92% à alcanÃada para a base de dados de arritmias do MIT-BIH. A tolerÃncia a ruÃdo do mÃtodo proposto foi tambÃm testada usando os registros padrÃo da base de dados MIT-BIH Noise Stress Test. A taxa da detecÃÃo do detector ficou aproximadamente 99,35% mesmo para as relaÃÃes sinal-ruÃdo (SNR) tÃo baixo quanto 6dB.
The most important task in the ECG signal processing is the accurate determina-tion of QRS complex, in particular, accurate detection of the R wave peaks, is essential in computer-based ECG analysis especially for a correct measurement of Heart Rate Variability (HRV). A great hurdle to be overcome in reliable detection is the sensibility of the electrocar-diogram to several disturbance sources such as powering source interference, movement arti-facts, baseline wandering and muscle noise. This study uses the Hilbert Transform pairs of wavelet bases for QRS detection. From the properties of these mathematical tools it was pos-sible to develop an algorithm which is able to differentiate the R waves from the others (P, Q, S, T and U waves).The performance of the algorithm was verified using the records MIT-BIH arrhythmia and normal databases. A QRS detection rate of 99.92% was achieved against MIT-BIH arrhythmia database. The noise tolerance of the proposed method was also tested using standard records from the MIT-BIH Noise Stress Test Database. The detection rate of the detector remains about 99.35% even for signal-to-noise ratios (SNR) as low as 6dB.
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Doumenq, Pierre. "Apport de l'infrarouge à transformée de Fourier et du couplage chromatographie gazeuse-infrarouge à transformée de Fourier à l'étude de systèmes chimiques complexes." Aix-Marseille 3, 1989. http://www.theses.fr/1989AIX30021.
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Zhang, Yarui. "Non-linear electromagnetic imaging : from sparsity-preserving wavelet-based algorithms to deep learning." Electronic Thesis or Diss., université Paris-Saclay, 2022. http://www.theses.fr/2022UPAST167.
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Ce travail traite de l'imagerie électromagnétique mal-posée non-linéaire à partir de données en régime harmonique dans une expérience de diffraction bidimensionnelle, en mettant l'accent sur deux approches dans le cadre de l'inversion de source de contraste (CSI). La première approche est un CSI pénalisé par la parcimonie de groupe dans le domaine des ondelettes, la seconde est un schéma d'apprentissage profond dit déroulé. Dans la première approche, une dépendance existe entre les coefficients d'ondelettes à différentes échelles, appelée relation parent-enfant, ce qui donne une structure quadtree d'ondelettes, de sorte que les coefficients d'ondelettes sont parcimonieux tant au niveau des pixels qu'au niveau des groupes. L'accent est mis sur l'utilisation de la transformée en ondelettes complexe (CWT) à double arborescence en vue d'obtenir correctement la représentation parcimonieuse par groupe recherchée. Une norme l2,1 ajoutée à la fonction coût standard applique la parcimonie de groupe aux coefficients d'ondelettes du contraste. La stratégie de réplication est combinée avec la méthode proximale afin de résoudre le problème pénalisé de groupes qui se chevauchent. La seconde approche est inspirée de la méthode déroulée. En intégrant les itérations CSI dans le modèle d'apprentissage profond, la connaissance du domaine est intégrée au processus d'apprentissage. Dans les deux cas, des tests numériques approfondis sont effectués afin d'évaluer les performances, la stabilité, la robustesse et la fiabilité, en menant des comparaisons avec des solutions considérées plus standard (comme CSI, la transformée en ondelettes discrète ou DWT, et U-net), et celles-ci illustrent l'avantage des deux approches proposées en de nombreux aspectsThis work deals with nonlinear ill-posed electromagnetic imaging from time-harmonic data within a two-dimensional scattering experiment, the focus being on two approaches in the framework of the contrast-source inversion (CSI). The first approach is a group sparsity penalized CSI in the wavelet domain, the second is an unrolled deep learning scheme. In the first approach, dependency exists between wavelet coefficients at different scales, referred to as parent-child relationship, which yields a wavelet quadtree structure so that wavelet coefficients are both pixel-wise and group-wise sparse. Emphasis is on the dual-tree complex wavelet transform (CWT) to achieve this result. A '2;1 norm added to the standard cost function is to enforce group sparsity onto the wavelet coefficients of the spatially-varying contrast. The replication strategy is combined with the proximal method to solve the overlapping group penalized problem. The second approach is inspired by the unrolled method. By embedding the CSI iterations into the deep learning model, the domain knowledge is incorporated into the learning process. In both cases, thorough numerical tests are carried out to evaluate performance, stability, robustness, and reliability with comparisons with more standard solutions (like CSI, discrete wavelet transform (DWT) and U-net), which exhibit the advantage of the proposed approaches under many aspects
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Ngari, Mwaniki Silas. "Fourier transform microwave rotational spectra of van der Waals complexes of N¦2O." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape7/PQDD_0031/NQ46894.pdf.
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Klingspor, Måns. "Hilbert Transform : Mathematical Theory and Applications to Signal processing." Thesis, Linköpings universitet, Matematik och tillämpad matematik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-122736.
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The Hilbert transform is a widely used transform in signal processing. In this thesis we explore its use for three different applications: electrocardiography, the Hilbert-Huang transform and modulation. For electrocardiography, we examine how and why the Hilbert transform can be used for QRS complex detection. Also, what are the advantages and limitations of this method? The Hilbert-Huang transform is a very popular method for spectral analysis for nonlinear and/or nonstationary processes. We examine its connection with the Hilbert transform and show limitations of the method. Lastly, the connection between the Hilbert transform and single-sideband modulation is investigated.
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Zhang, Yi. "Spatially Non-Uniform Blur Analysis Based on Wavelet Transform." University of Dayton / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1292527349.
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Zhang, Haizhen. "Characterization of Cucurbituril Complex Ions in the Gas Phase Using Electrospray Ionization Fourier Transform Ion Cyclotron Resonance Mass Spectrometry." Diss., CLICK HERE for online access, 2006. http://contentdm.lib.byu.edu/ETD/image/etd1582.pdf.
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Leon, Nick. "Complex city systems : how cities are using technological systems to transform and compete in a global knowledge based economy." Thesis, Imperial College London, 2010. http://hdl.handle.net/10044/1/11516.
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Benigni, Paolo. "Trapped Ion Mobility Spectrometry coupled to Fourier Transform Ion Cyclotron Resonance Mass Spectrometry for the analysis of Complex Mixtures." FIU Digital Commons, 2017. https://digitalcommons.fiu.edu/etd/3547.
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Analytical Characterization of complex mixtures, such as crude oil, environmental samples, and biological mixtures, is challenging because of the large diversity of molecular components. Mass spectrometry based techniques are among the most powerful tools for the separation of molecules based on their molecular composition, and the coupling of ion mobility spectrometry has enabled the separation and structural elucidation using the tridimensional structure of the molecule. The present work expands the ability of analytical chemists by furthering the development of IMS-MS instrumentation by coupling Trapped Ion Mobility Spectrometry to Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (TIMS-FT-ICR MS). The TIMS-FT-ICR MS platform combines the high-resolution separation of TIMS, which has mobility resolving powers up to 400, and ultra-high mass resolution of FT-ICR MS, with mass resolving power over 1,000,000. This instrumentation allows the assignment of exact chemical composition for compounds in a complex mixture, as well as measurement of the collision cross-section of the molecule. Herein, the principles of the TIMS separation and its coupling to FT-ICR MS are described, as well as how the platform can be applied to targeted analysis of molecules, and untargeted characterization of complex mixtures.
Molecular standards were analyzed by TIMS-MS in order to develop a computational workflow that can be utilized to elucidate molecular structure, using the measured collision cross-section of the ion. This workflow enabled identification of structural, cis/trans isomers, and chelated molecules and provides the basis for unsupervised structural elucidation of a complex mixture, and in particular for the elucidation of hydrocarbons from fossil fuels. In summary, this work presents the coupling of TIMS-FT-ICR MS and provides examples of applications as a proof of concept of the potential of this platform for solving complex analytical challenges.
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Connelly, James Patrick. "Microwave studies of Van der Waals complexes." Thesis, University of Oxford, 1993. http://ora.ox.ac.uk/objects/uuid:3865eb1d-d288-44c9-8d42-84f7ff2c0608.
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This thesis describes the commissioning and development of a pulsed supersonic nozzle, Fourier-transform microwave spectrometer and its application to the study of several weakly bound van der Waals complexes. A pulsed supersonic expansion, Fourier-transform microwave spectrometer based on the Flygare design with a number of modifications has been constructed with an operating range of 6-18 GHz. A homodyne detection circuit mixing signals to modulus values between dc and 1 MHz is used, requiring two measurements to determine absolute transition frequencies. Transition frequencies are measured from the power spectrum by determining the first derivative zero crossing point in a least squares fitting procedure. Semiautomation of many of the spectrometer operations has been achieved allowing unattended data collection over scans of up to 300 MHz. The microwave spectrum of Ar2-OCS and Ar2-OC34S has been observed and analysed using conventional Watson S reduction hamiltonian parameters. Effective structural parameters are derived and used in a harmonic force field analysis, based on the centrifugal distortion constants, to compare the trimer interations with a model based on the sum of dimer interactions. A series of complexes containing the nitrogen molecule undergoing tunnelling motions have been studied. Hyperfine matrix elements for the first order nuclear quadrupole interaction are derived for the coupled identical nuclei case appropriate to the rapid tunnelling motions observed. The microwave spectrum of N2-OCS is described. Tunnelling and nuclear spin statistical effects for two symmetry states are observed arising from the interchange of nitrogen nuclei. Rotational and quadrupole constants are derived; an accidental near degeneracy of two rotational levels allows the off-diagonal quadrupole coupling constant to be determined from second order effects. A tunnelling hamiltonian fitting the quadrupole coupling constants to an angular potential has been used to calculate the tunnelling frequency and barrier to N2 rotation. The microwave spectrum of N2-O3 and a preliminary spectrum of N2-SO3 have been observed. Rotation-inversion motions of the O3 and SO2 moieties must be considered in addition to the N2 tunnelling to fit the spectrum. Tunnelling frequencies for the O3/SO2 and geared motions with the N2 are derived as well as structural parameters. Modifications for production of refractory molecules and complexes by laser ablation have been made. A modified nozzle employing rods of material is used with the ablation process taking place in the nozzle throat. Modifications to obtain an expansion along the axis of the microwave cavity employ a hemispherical Fabry-Perot cavity configuration. The system has been tested on a number of diatomic molecules including PbS and CuCl.
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Moudens, Audrey. "Formation de complexes moléculaires hydratés appliquée aux sciences planétaires." Rennes 1, 2010. http://www.theses.fr/2010REN1S210.
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Les clathrates hydrates sont des structures cristallines formées de cages de molécules d’eau reliées entre elles par liaison hydrogène et qui piègent en leur centre une molécule de gaz appelée molécule hôte. Leur présence est suspectée à la surface de nombreux corps glacés du système solaire, dont les conditions thermodynamiques semblent favorables à leur stabilité. Nous avons notamment montré par des simulations qu’ils pouvaient se trouver à la surface de Pluton et Triton. Des modèles astrophysiques ont établi par ailleurs que ces structures cristallines ont probablement été incorporées aux planétésimaux à partir desquels les corps planétaires se sont formés au sein de la nébuleuse primitive. Un des objectifs de mon travail a été de valider cette hypothèse. Les conditions de basses températures (10-100K) et basses pressions (105-5-10-44 mbar) régnant dans la nébuleuse primitive ont été reproduites en laboratoire par la mise en détente supersonique d’un mélange de vapeur d’eau et de gaz. La spectroscopie infrarouge par transformée de Fourier par absorption donne accès à la nature et à la dynamique des complexes moléculaires qui se forment dans le jet supersonique. Sous certaines conditions une condensation mixte de molécules d’eau et d’atomes d’argon a été observée. L’interprétation des spectres infrarouges, basée sur des calculs de chimie quantique, a révélé que sur la durée d’une détente typiquement inférieure à 100 µs, ce sont les atomes d’argon qui viennent enrober les molécules d’eau et non l’inverse. Ce résultat ne remet pas forcément en cause la formation de clathrates en jet supersonique, mais montre que des temps plus longs sont nécessaires à un réarrangement des molécules agrégées vers la structure clathrate. Une deuxième étude a été réalisée sur le dispositif Jet-AILES implanté au synchrotron Soleil, à partir d’un mélange gazeux de vapeur d’eau et de CO2. Des complexes hétérogènes (H2O)m-(CO2)n et (CO2)n ont été détectés à haute résolution. Le transport des particules de poussière par le processus de photophorèse au sein de la nébuleuse primitive a également été étudié. Nos simulations ont montré que les particules de poussières parviennent à de larges distances héliocentriques grâce au mécanisme de photophorèse et confirment l’hypothèse de l’accrétion par les comètes des minéraux haute température dans les régions externes de la nébuleuse solaire. Enfin, la spectroscopie infrarouge haute température de l’acétylène, molécule présente dans les enveloppes circumstellaires des étoiles froides carbonées est présentée. La source haute enthalpie réalisée précédemment au laboratoire a permis l’acquisition de spectres haute résolution de l’acétylène entre 800 K et 1455 K. La simulation des spectres à l’aide d’un modèle de transfert radiatif a montré que l’épaisseur optique de l’échantillon sondé était à l’origine d’une altération du rapport d’intensité entre raies ortho et para. Cette anomalie s’est avérée être un moyen efficace pour extraire la densité-colonne de nos échantillons et pourrait être utilisée pour accéder à celles des enveloppes circumstellaires des étoiles froides carbonéesClathrate hydrates are crystalline compounds consisting of guest molecules of gas trapped inside cages of hydrogen bonded water molecules. They are suspected to be present on icy planetary surfaces in the solar system, where thermodynamics conditions are favorable to their stability. We showed by simulations that they can exist on the surfaces of Pluto and Triton. Astrophysical models established that these crystalline structures could be incorporated in planetesimals in the solar nebula, from which planets formed. The aim of my work was to check this hypothesis, reproducing low temperature (10-100 K) and low pressure (10-5-10-4 mbar) conditions of the solar nebula, using supersonic expansion of water vapour and gas mixtures. Fourier Transform Infrared Absorption Spectroscopy was used to retrieve nature and dynamics of molecular complexes formed in the supersonic jet. Under some conditions, mixed condensate of water vapour and argon was observed. The interpretation of the infrared spectra based on quantum chemistry calculations, revealed that on the typical timescale of 100 µs during the expansion, argon atoms surround water aggregates, while they would have been trapped inside cages of hydrogen bonded water molecules in the case of a clathrate structure. This result do not necessarily compromise the formation of clathrate hydrates in the jet, but means that longer times are needed to the rearrangement of molecules toward a clathrate structure. A second study was realized using Jet-AILES apparatus at Synchrotron Soleil, with a gaseous mixture of water vapour and carbon dioxide. Heterogeneous complexes (H2O)m-(CO2)n and (CO2)n were detected at high resolution. The transport of dusty particles in the solar nebula by photophoresis was also investigated. Our simulations showed that dusty particles are able to reach large heliocentric distances under the photophoretic effect. It confirms the hypothesis of accretion of high temperature minerals by comets in the outer part of the solar nebula. Finally, high temperature spectroscopy of acetylene, molecule formed in the circumstellar envelopes of cold carbon stars, is presented. The high enthalpy source previously designed in the laboratory was used to produce high resolution spectra of acetylene between 870 K and 1455 K. The simulation of spectra with the help of a radiative transfer model revealed that the optical thickness of the probed gas sample affected the intensity ratio between ortho and para lines. This anomaly turned out to be a good way to estimate the acetylene concentration in the samples and can be used to characterize circumstellar envelopes
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Camargo, Rubens de Figueiredo. "Do teorema de Cauchy ao metodo de Cagniard." [s.n.], 2005. http://repositorio.unicamp.br/jspui/handle/REPOSIP/307011.
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Orientador: Edmundo Capelas de OliveiraDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Matematica, Estatistica e Computação Cientifica
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Resumo: Este trabalho versa sobre variaveis complexas, em particular sobre o teorema integral de Cauchy, suas consequencias e aplicações. Como consequencia do teorema integral de Cauchy temos o teorema dos residuos, peça chave para o desenvolvimento deste trabalho. Nas aplicações nos concentramos no estudo das transformadas integrais como metodologia na resolução de equações diferenciais parciais, em particular no calculo da inversão das transformadas de Laplace, Fourier e Hankel, bem como na justa posição das transformadas. Para inversão da justa posição das transformadas nos concentramos no metodo de Cagniard e algumas de suas variações
Abstract: This work is about complex variables, in particular about Cauchy¿s integral theorem and its consequences and applications. We have, as consequences of Cauchy¿s integral theorem, Cauchy¿s theorem and the residue theorem, a keynote to the development of this work. As for the applications, our main objective was to study the integral transforms as a method to solve partial differential equations and, specifically, the inversion of the Laplace, Fourier and Hankel transforms, in the same way, the juxtaposition of transforms. In order to invert the juxtaposition of transforms our main concern was to study Cagniard¿s method and some of its variations
Mestrado
Matematica Aplicada
Mestre em Matemática
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Febrer, Pedro Maria Ulisses dos Santos Jalhay. "Residue sum formula for pricing options under the variance Gamma Model." Master's thesis, Instituto Superior de Economia e Gestão, 2020. http://hdl.handle.net/10400.5/20802.
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Mestrado em Mathematical FinanceO resultado principal desta dissertação é a demonstração da fórmula de serie de soma tripla para o preço de uma opção Europeia induzido por um processo Variance Gamma. Com esta intenção, apresentamos certas propriedades e noções sobre processos de Lévy e análise complexa multidimensional, dando ênfase à aplicação do cálculo de resíduos ao integral Mellin-Barnes. Subsequentemente, iremos construir a representação na forma do integral Mellin-Barnes, em C^3, para o preço de uma opção e, apoiados pelo anteriormente mencionado cálculo de resíduos, deduziremos a representação em serie de soma tripla para o preço de uma opção Europeia e os seus correspondentes gregos. Para terminar, dando uso à nova formula, serão computados e discutidos alguns valores para um caso de estudo particular.
The main result of this dissertation is the proof of the triple sum series formula for the price of an European call option driven by the Variance Gamma process. With this intention, we present some notions and properties of Lévy processes and multidimensional complex analysis, with emphasis on the application of residue calculus to the Mellin-Barnes integral. Subsequently, we construct the Mellin-Barnes integral representation, in C^3, for the price of the option and, buttressed with the aforementioned residue calculus, we deduce the triple sum series representation for the price of the European option and its corresponding greeks. Finally, with the use of the new formula, some values for a particular case study are computed and discussed.
info:eu-repo/semantics/publishedVersion
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Liang, Zhenmin. "High precision Fourier transform ion cyclotron resonance mass spectral analysis of polymers and metal complexes /." The Ohio State University, 1990. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487685204968068.
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Grigorean, Gabriela. "Chiral studies of non-covalent complexes by electrospray ionization (ESI) Fourier transform mass spectrometry (FTMS) /." For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2002. http://uclibs.org/PID/11984.
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Ahmed, Abdelwahab Ibrahim. "Protein secondary structure of the isolated photosystem II (PSII) particles and light-harvesting complex (LHCII) studied by Fourier transform infrared spectroscopy." Thèse, Université du Québec à Trois-Rivières, 1996. http://depot-e.uqtr.ca/6803/1/000626119.pdf.
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Aragão, Gilton Alves. ""Agroindústria e cooperativismo na Bahia" : uma análise do complexo agroindustrial baiano e das possibilidades das cooperativas agrícolas transformá-lo." Faculdade de Economia, 1988. http://repositorio.ufba.br/ri/handle/ri/23296.
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A questão básica que se pretende discutir, é se o cooperatismo pode significar uma alternativa capaz de contribuir para transformar a agricultura e agroindústria do Estado da Bahia.
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YVER, BEATRICE. "Analyse de matrices organiques complexes par couplage de la chromatographie en phase supercritique avec l'infrarouge a transformee de fourier." Paris 6, 1996. http://www.theses.fr/1996PA066438.
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L'etude de matrices organiques complexes en liaison avec l'environnement telles que les tensioactifs non ioniques, les silicones, les jus issus de la carbonisation de la biomasse, implique l'emploi de techniques chromatographiques tres resolutives. Dans le but d'une identification des differents constituants de ces matrices, le couplage au systeme chromatographique de detecteurs non seulement specifiques mais egalement generateurs d'informations structurales se revele capital. C'est dans cet esprit qu'ont ete apprehendees les potentialites du couplage en ligne de la chromatographie en phase supercritique capillaire avec la spectroscopie infrarouge a transformee de fourier, la phase mobile utilisee etant le dioxyde de carbone. Ainsi, ce couplage se revele bien adapte a l'etude des silicones permettant une resolution satisfaisante des polydimethylsiloxanes fonctionnalises ou non et presentant des degres de polymerisation relativement eleves, une differenciation des homologues lineaires et cycliques ainsi qu'une analyse des copolymeres. Lors de l'etude des jus issus de la carbonisation de la biomasse, le couplage cps/irtf, qui s'avere complementaire du couplage de la chromatographie en phase gazeuse avec la spectrametrie de masse, permet de confirmer ou d'infirmer la presence de certains produits et ainsi de lever d'eventuelles ambiguites. Enfin, dans le cas des tensioactifs non ioniques, une resolution partielle des copolymeres de polyethyleneglycols et de polypropyleneglycols peut etre envisagee a l'aide de ce couplage
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Романишен, Олег Валерійович, and Oleh Romanyshen. "Розробка заходів забезпечення безперебійної роботи електричного обладнання підприємства з переробки молока." Master's thesis, Тернопільський національний технічний університет імені Івана Пулюя, кафедра електричної інженерії,Тернопіль, Україна, 2020. http://elartu.tntu.edu.ua/handle/lib/33492.
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Сьогодні в сучасній електроенергетиці, з її
тенденцією повсюдної автоматизації, висока надійність електропостачання
становиться одним із головних пріоритетів (якщо не найголовнішим). Зазвичай
щоб покращити надійність електропостачання промислового підприємства,
необхідно покращити систему живлення, тобто забезпечити потрібною
кількістю трансформаторів, генераторів, ліній живлення, секцій шин та
засобами автоматизації.
Взявши все вищесказане до уваги можна зробити висновок, що перед
нами, як інженерами, стоїть два основних типи завдань: завдання аналізу та
завдання синтезу. До завдань аналізу можна віднести: кількісне оцінювання
показників надійності елементів і систем, оцінювання надійності
електропостачання споживачів за відомих параметрів, режимів і конфігурацій
електричних систем. В свою чергу завдання синтезу, в основному, полягають у
виборі найбільш оптимальних рішень під час планування, проектування,
спорудження та подальшої експлуатації електричних систем, і по можливості
під час виготовлення. Тому актуальним є на основі аналізу діючої системи
електроспоживання заводу забезпечувати надійність системи
електропостачання за рахунок комплексного впровадження технічних та
організаційних заходів.В кваліфікаційній роботі проведено визначення категорії по надійності електропостачання та характеристика споживачів електричної енергії. Здійснено розрахунок навантаження та вибір схеми електропостачання. Здійснено розрахунок та вибір пристрою компенсації. Проведено вибір потужності та числа трансформаторів на ПС. Здійснена розробка конструкції КТП. Здійснено розрахунки та вибір розподільної електричної мережі.
The qualification work defines the category of reliability of electricity supply and characteristics of electricity consumers. The load is calculated and the power supply scheme is selected. The calculation and selection of the compensation device is performed. The power and number of transformers on the substation were selected. The design of KTP is developed. Calculations and selection of the electrical distribution network have been performed
ВСТУП …6 1 АНАЛІТИЧНИЙ РОЗДІЛ ...9 1.1 Огляд підприємства …9 1.1.1 Загальні дані…9 1.1.2 Обґрунтування технології виробництва…10 1.1.3 Виробництво сиру…10 1.1.4 Технологія виробництва сиру…13 1.1.5 Холодопостачання…17 1.1.6 Рівень механізації та автоматизації виробництва…18 1.1.7 Штат працівників. Графік роботи…19 1.2 Огляд спліт-системи…19 1.3 Поняття та класифікація відмов…21 1.4 Особливості системи та елемента в теорії надійності…23 2 РОЗРАХУНКОВО–ДОСЛІДНИЦЬКИЙ РОЗДІЛ ...25 2.1 Проектування системи електроосвітлення заводу…25 2.1.1 Види освітлення…25 2.1.2 Світлотехнічний розрахунок робочого освітлення …25 2.1.3 Світлотехнічний розрахунок робочого освітлення за допомогою методу коефіцієнта використання на прикладі приміщення № 15…26 2.1.4 Аварійне освітлення…36 2.2 Проектування мережі електропостачання…37 2.2.1 Вибір силових розподільних пунктів …37 2.2.2 Вибір кабелів 0,4 кВ…45 2.2.3 Розрахунок кабельної лінії…45 2.2.4 Вибір комутаційних апаратів 0,4 кВ…46 2.3 Висновки до розділу…47 3 ПРОЕКТНО-КОНСТРУКТОРСЬКИЙ РОЗДІЛ ....48 3.1 Проектування блискавкозахисту будівлі… 48 3.1.1 Коротка характеристика об’єкту...48 3.1.2 Необхідність виконання блискавкозахисту...48 3.1.3 Влаштування системи блискавкоприймачів....49 3.1.4 Влаштування системи струмовідводів...51 3.1.5 Влаштування системи заземлення...52 3.1.6 Монтаж блискавкоприймачів...53 3.1.7 Монтаж струмовідводів...53 3.1.8 Монтаж заземлювачів...54 3.1.9 Експлуатація та технічне обслуговування системи блискавкозахисту...55 3.2 Вибір типу і потужності трансформаторів...55 3.2.1 Порівняльний розрахунок трансформаторів...55 3.2.2 Коротка інформація про Комплектну трансформаторну підстанцію КТПГСМ...59 3.3 Вибір пристрою компенсації реактивної напруги...64 3.4 Висновки до розділу...65 4 ОХОРОНА ПРАЦІ ТА БЕЗПЕКА В НАДЗВИЧАЙНИХ СИТУАЦІЯХ... 66 4.1. Загальні положення інструкції з охорони праці для електрика... 66 4.2. Вимоги безпеки для електрика перед виконанням робіт...69 4.3. Вимоги безпеки під час виконання електриком робіт...69 4.4. Вимоги безпеки для електрика після закінчення робіт...73 4.5.Вимоги безпеки для електрика в аварійних ситуаціях...73 ЗАГАЛЬНІ ВИСНОВКИ ...74 ПЕРЕЛІК ПОСИЛАНЬ ...75 ДОДАТКИ...1 Додаток А. Порівняльний розрахунок трансформаторів...2