Dissertations / Theses: 'Spectral and temporal analysis'

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Everett, M. S. "The temporal and spectral characteristics of recorded music." Thesis, Coventry University, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.382924.

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Mello, Marcio Pupin. "Spectral-temporal and Bayesian methods for agricultural remote sensing data analysis." Instituto Nacional de Pesquisas Espaciais (INPE), 2013. http://urlib.net/sid.inpe.br/mtc-m19/2013/09.17.18.58.

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Informações agrícolas confiáveis tem se tornado cada vez mais importantes para os tomadores de decisões. Especialmente quando são obtidas em tempo hábil, essas informações são altamente relevantes para o planejamento estratégico do país. Apesar de o sensoriamento remoto mostrar-se promissor para aplicações em mapeamento agrícola, com potencial de melhorar as estatísticas agrícolas oficiais, esse potencial não tem sido amplamente explorado. Existem poucos exemplos bem sucedidos do uso operacional do sensoriamento remoto para mapeamento sistemático de culturas agrícolas e, para garantir resultados precisos, eles são fortemente baseados em interpretação visual de imagens. De fato, apesar dos substanciais avanços em análise de dados de sensoriamento remoto, novas técnicas para automatizar a análise de dados em sensoriamento remoto com aplicações agrícolas são desejáveis, especialmente no propósito de manter a consistência e a precisão dos resultados. Neste contexto, existe uma demanda crescente pelo desenvolvimento e implementação de métodos automatizados de análise de dados de sensoriamento remoto com aplicações em agricultura. Assim, o principal objetivo desta tese é propor o desenvolvimento e a implementação de métodos para automatizar a análise de dados de sensoriamento remoto em aplicações agrícolas, com foco na consistência e precisão dos resultados. Este documento foi escrito como uma coleção de dois artigos, cada um com foco nos seguintes pontos: (i) análise multitemporal, multiespectral e multisensor, permitindo a descrição das variações espectrais de alvos agrícolas ao longo do tempo; e (ii) inteligência artificial na modelagem de fenômenos usando dados de sensoriamento remoto e informações complementares de maneira integrada. Dois estudos de caso referentes ao mapeamento da colheita da cana em São Paulo e ao mapeamento da soja no Mato Grosso foram usados para testar as metodologias batizadas de STARS e BayNeRD, respectivamente. Os resultados dos testes confirmaram que ambos os métodos propostos foram capazes de automatizar processos de análises de dados de sensoriamento remoto com aplicações agrícolas, com consistência e precisão. Reliable agricultural statistics has become increasingly important to decision makers. Especially when timely obtained, agricultural information is highly relevant to the strategic planning of the country. Although remote sensing shows to be of great potential for agricultural mapping applications, with the benefit of further improving official agricultural statistics, its potential has not been fully explored. There are very few successful examples of operational remote sensing application for systematic mapping of agricultural crops, and they are strongly supported by visual image interpretation to allow accurate results. Indeed, despite the substantial advances in remote sensing data analysis, techniques to automate remote sensing data analysis focusing on agricultural mapping applications are highly valuable but have to maintain consistency and accuracy. In this context, there continues to be a demand for development and implementation of computer aided methods to automate the processes of analyzing remote sensing datasets for agriculture applications. Thus, the main objective of this thesis is to propose implementation of computer aided methodologies to automate, maintaining consistency and accuracy, processes of remote sensing data analyses focused on agricultural thematic mapping applications. This thesis was written as a collection of two papers related to a core theme, each addressing the following main points: (i) multitemporal, multispectral and multisensor image analysis that allow the description of spectral changes of agricultural targets over time; and (ii) artificial intelligence in modeling phenomena using remote sensing and ancillary data. Study cases of sugarcane harvest in São Paulo and soybean mapping in Mato Grosso were used to test the proposed methods named STARS and BayNeRD, respectively. The two methods developed and tested confirm that remotely sensed (and ancillary) data analysis can be automated with computer aided methods to model a range of cropland phenomena for agriculture applications, maintaining consistency and accuracy.

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Kuster, Markus. "Combined spectral and temporal analysis of a Her X-1 turn-on." [S.l. : s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=971486271.

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Malfrait, Paul. "Temporal spectral unmixing for rapid detection of radiological events by gamma ray spectrometry." Electronic Thesis or Diss., université Paris-Saclay, 2023. http://www.theses.fr/2023UPASG055.

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Cette thèse vise à améliorer les algorithmes de démélange de spectres gamma afin de pouvoir accélérer la détection d'anomalie et l'estimation des contributions des radionucléides contenus dans les filtres aérosols analysés par l'Institut de Radioprotection et de Sûreté Nucléaire. Pour ce faire nous avons développé un algorithme de démélange de spectre qui analyse conjointement plusieurs mesures successives d'un même échantillon.Cet algorithme a ensuite été amélioré afin de pouvoir mener l'analyse en temps réel pendant que la mesure du spectre gamma est réalisée. Divers outils ont dû être développés en même temps que cet algorithme pour permettre d'estimer précisémment les activités des radionnucléides, notamment la calibration des signatures spectrales utilisées lors du démélange.Les résultats de ces études sont présentés dans la thèse à la fois sur des spectres simulés et sur des spectres réels issus des analyses de routine du laboratoire. La détection d'une contamination de ¹²³I à 2 Bq dans un échantillon au bout de 2 minutesde mesure illustre bien l'accélération permise par les développement de cette thèse. En effet, cette détection n'aurait pas été possible avec les outils utilisés en routine The aim of this thesis is to improve spectral unmixing algorithms in gamma ray spectrometry in order to speed up anomaly detection and the estimation of radionuclide contributions in aerosol filter samples analyzed by the French Institute of Radiation Protection and Nuclear Safety. To this end, we have developed an unmixing algorithm that performs joint analysis of several successive measurements of the same sample. This algorithm has been improved to enable online analysis while the gamma-ray spectrum measurement is measured. Various tools had to be developed at the same time as this algorithm to enable radionuclide activities to be estimated accurately, including calibration of the spectral signatures used during the unmixing process.The results of these studies are presented in the thesis both on simulated spectra and on real spectra from the laboratory's routine analyses. The detection of a contamination of ¹²³I at 2 Bq in a sample after 2 minutes of measurement illustrates the acceleration made possible by the developments made during this thesis. Indeed, this detection would not have been possible with the tools used routinely

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Garges, David Casimir. "Early Forest Fire Detection via Principal Component Analysis of Spectral and Temporal Smoke Signature." DigitalCommons@CalPoly, 2015. https://digitalcommons.calpoly.edu/theses/1456.

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The goal of this study is to develop a smoke detecting algorithm using digital image processing techniques on multi-spectral (visible & infrared) video. By utilizing principal component analysis (PCA) followed by spatial filtering of principal component images the location of smoke can be accurately identified over a period of exposure time with a given frame capture rate. This result can be further analyzed with consideration of wind factor and fire detection range to determine if a fire is present within a scene. Infrared spectral data is shown to contribute little information concerning the smoke signature. Moreover, finalized processing techniques are focused on the blue spectral band as it is furthest away from the infrared spectral bands and because it experimentally yields the largest footprint in the processed principal component images in comparison to other spectral bands. A frame rate of .5 images/sec (1 image every 2 seconds) is determined to be the maximum such that temporal variance of smoke can be captured. The study also shows eigenvectors corresponding to the principal components that best represent smoke and are valuable indications of smoke temporal signature. Raw video data is taken through rigorous pre-processing schemes to align frames from respective spectral band both spatially and temporally. A multi-paradigm numerical computing program, MATLAB, is used to match the field of view across five spectral bands: Red, Green, Blue, Long-Wave Infrared, and Mid-Wave Infrared. Extracted frames are aligned temporally from key frames throughout the data capture. This alignment allows for more accurate digital processing for smoke signature. v Clustering analysis on RGB and HSV value systems reveal that color alone is not helpful to segment smoke. The feature values of trees and other false positives are shown to be too closely related to features of smoke for in solely one instance in time. A temporal principal component transform on the blue spectral band eliminates static false positives and emphasizes the temporal variance of moving smoke in images with higher order. A threshold adjustment is applied to a blurred blue principal component of non-unity principal component order and smoke results can be finalized using median filtering. These same processing techniques are applied to difference images as a more simple and traditional technique for identifying temporal variance and results are compared.

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Jennings, Amanda R. "On mechanisms for the analysis of spectral and temporal envelope shape in the human auditory system." Thesis, University of Newcastle Upon Tyne, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.413390.

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Kriss, Alissa Brynn. "The Role of Environmental, Temporal, and Spatial Scale on the Heterogeneity of Fusarium Head Blight of Wheat." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1320932280.

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Guo, Ziyuan. "Objective Audio Quality Assessment Based on Spectro-Temporal Modulation Analysis." Thesis, KTH, Ljud- och bildbehandling, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-91847.

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Objective audio quality assessment is an interdisciplinary research area that incorporates audiology and machine learning. Although much work has been made on the machine learning aspect, the audiology aspect also deserves investigation. This thesis proposes a non-intrusive audio quality assessment algorithm, which is based on an auditory model that simulates human auditory system. The auditory model is based on spectro-temporal modulation analysis of spectrogram, which has been proven to be effective in predicting the neural activities of human auditory cortex. The performance of an implementation of the algorithm shows the effectiveness of the spectro-temporal modulation analysis in audio quality assessment.

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Zhang, Chi, and 张驰. "Ultrafast temporal spectroscopy based on parametric mixing time-lens." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2013. http://hdl.handle.net/10722/200358.

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With the increased requirement on the ultrafast measurement technology, how to resolve the spectral dynamics has the top priority on the research list, since spectrum is an essential carrier for most of the physical or chemical phenomena. According to the Nyquist-Shannon sampling theorem, if a function 𝑥(𝑡) contains no frequencies higher than 𝐵 Hz, it is completely determined by giving its ordinates at a series of points spaced 1/(2𝐵) seconds apart. Since most of the conventional optical spectrum analyzers (OSAs) are operated with the sampling rate (or frame rate) of 5 Hz, it results in the resolvable bandwidth of the spectrum dynamic is less than 2.5 Hz. With the development of the space-time duality, the analogy transforms the conventional spatial dimension into the time axis, and the well-known spatial models inspire us in performing their counterparts in the time domain. As one of the most powerful tools in achieving ultrafast time axis information, time-lens plays a more and more important role in the single-pixel imaging system. By fully analyzing the diploma of the previous optical spectrum resolving mechanisms, in this thesis, for the first time, we raised up the concept the parametric spectrotemporal analyzer (PASTA), which is based on the time-lens focusing mechanism. Here the spectrum resolving frame rate is increased to 100 MHz, then the observable spectrum dynamic bandwidth could be 50 MHz, which is sufficient for most of the ultrafast phenomena. In the PASTA system, the time-lenses are implemented with the fiber optical parametric amplifier (FOPA) based parametric mixer, which provides higher conversion efficiency and repetition rate. On the other hand, the dispersion based dispersive Fourier transformation (DFT) technology generates the swept-pump for the FOPA, as well as the temporal dispersion medium. This research in this thesis is a fundamental study on the newly PASTA system, from its origin and the theoretical background, to the implementation techniques and operation performances. From its implementation, its principles are strongly related with the combination of the dispersion and the Kerr nonlinear effects, especially the swept-pump FOPA in the time-lens part. The DFT technique, in generating the fast swept-source, has also find its applications in the ultrafast serial time-encoded amplified microscopy (STEAM) and swept-source optical coherence tomography (SS-OCT) systems. Finally, the single-lens PASTA prototype is capable of resolving 5-nm wavelength range with 0.03-nm resolution under 100-MHz frame rate. Moreover, besides the singlelens PASTA, the telescope/wide-angle configurations have also been investigated experimentally to achieve the spectrum zoom in/out ratio as high as 17 times, here we have obtained the sharpest resolution of 5 pm (<1 GHz) with the telescope configuration, and the widest observation range of 9 nm with the wide-angle configuration. My research efforts presented in this thesis mainly leverage the ultrafast characteristics of the time-lens system, from theory to implementation, and achieve the real-time optical spectrum analysis – the PASTA system. PASTA is not only essential in observing some non-repetitive ultrafast phenomena, but also provides a potential solution for the frequency to time transformation in some ultrafast bio-medical imaging systems. published_or_final_version Electrical and Electronic Engineering Doctoral Doctor of Philosophy

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Orstavik, Odd-Halvdan Sakse. "Analysis of chaotic multi-variate time-series from spatio-temporal dynamical systems." Thesis, University College London (University of London), 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.314071.

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Riml, Joakim. "Solute Transport Across Scales : Time Series Analyses of Water Quality Responses to Quantify Retention and Attenuation Mechanisms in Watersheds." Doctoral thesis, KTH, Vattendragsteknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-149528.

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The intra-continental movement of waterborne contaminants is governed by the distribution of solute load in the landscape along with the characteristics and distribution of the hydrological pathways that transport the solutes. An understanding of the processes affecting the transport and fate of the contaminants is crucial for assessments of solute concentrations and their environmental effect on downstream recipients. Elevated concentration of nutrients and the presence of anthropogenic substances, such as pharmaceutical residues, are two examples of the current problems related to hydrological transport. The overall objective of this thesis is to increase the mechanistic understanding of the governing hydrological transport processes and their links to geomorphological and biogeochemical retention and attenuation processes. Specifically, this study aims to quantify the processes governing the transport and fate of waterborne contaminants on the point, stream reach, and watershed scales by evaluating time series obtained from stream tracer tests and water quality monitoring data. The process quantification was achieved by deriving formal expressions for the key transport characteristics, such as the central temporal moments of a unit solute response function and the spectral scaling function for time series of solute responses, which attributes the solute response in the Laplace and Fourier domains to the governing processes and spatial regions within the watershed. The results demonstrate that in addition to the hydrological and biogeochemical processes, the distribution of the load in the landscape and the geomorphological properties in terms of the distribution of transport pathway distances have defined effects on the solute response. Furthermore, the spatial variability between and along the transport pathways significantly affect the solute response. The results indicate that environments with high retention and attenuation intensity, such as stream-reaches with pronounced hyporheic zones, may often dominate the solute flux in the watershed effluent, especially for reactive solutes. The mechanistic-based framework along with the evaluation methodologies presented within this study describes how the results can be generalized in terms of model parameters that reflect the hydrology, geomorphology and biogeochemistry in the studied area. This procedure is demonstrated by the parameterization of a compartment-in-series model for phosphorous transport. QC 20140826

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BECKER, Carmem Terezinha. "Índices climáticos para o estado da Paraíba: determinação e evolução temporal com abordagem na análise espectral." Universidade Federal de Campina Grande, 2017. http://dspace.sti.ufcg.edu.br:8080/jspui/handle/riufcg/1449.

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Submitted by Emanuel Varela Cardoso (emanuel.varela@ufcg.edu.br) on 2018-08-14T18:56:43Z No. of bitstreams: 1 CARMEM TEREZINHA BECKER – TESE (PPGMet) 2017.pdf: 9194940 bytes, checksum: cf8719dfce267520672b602612413ac2 (MD5) Made available in DSpace on 2018-08-14T18:56:43Z (GMT). No. of bitstreams: 1 CARMEM TEREZINHA BECKER – TESE (PPGMet) 2017.pdf: 9194940 bytes, checksum: cf8719dfce267520672b602612413ac2 (MD5) Previous issue date: 2017-08-04 Capes Ao apresentar extensa área inclusa na delimitação semiárida do Brasil, mais de 86% do seu território, a Paraíba é um dos estados brasileiros onde a aridez apresenta maior severidade. A disponibilidade de água impera como um processo decisivo no que diz respeito ao seu efetivo desenvolvimento ambiental, social e econômico, o qual é intimamente dependente das condições climáticas reinantes. Neste contexto, emerge a necessidade da quantificação de índices que tenham como propósito, a caracterização climática de um determinado local, para com isto, haver uma melhor adequação às classes de clima predominantes. Assim, o presente estudo tem por objetivo, tecer cenários passados da variabilidade espacial e temporal de índices climáticos. Para tanto, são calculados índices climáticos a partir de dados normais climatológicos e seriais anuais para um período de cinquenta anos a vinte postos pluviométricos criteriosamente selecionados e distribuídos ao longo do estado da Paraíba. Leva-se em consideração a metodologia proposta por Thornthwaite (1948) e pelo índice de aridez aplicado pelo United Nations Environment Programme - UNEP (1992). Toma-se como subsídio, a aplicação conceitual de métodos espectrais com a subsequente aplicação da análise de ondaletas aos índices climáticos seriais. Resulta-se, que mesmo metodologias distintas venham a produzir classificações climáticas diferentes para um mesmo local e período de tempo, o desenvolvimento das variabilidades interanual e interdecenal são extremamente semelhantes, recomendando os mesmos agentes como causadores destas variabilidades. Mesmo assim, o índice de aridez do UNEP mostra-se menos criterioso para classificações climáticas do que na utilização dos índices de Thornthwaite, evidenciando quadros de menor aridez. Pela metodologia das ondaletas, a variabilidade interdecenal é significativamente mais aparente do que a interanual, com a marcante predominância na escala de 11 anos, interagindo com escalas menores, de 5, 3,5 e 2,5 anos, os quais tendem a seguir os principais comportamentos da variabilidade térmica nas bacias dos oceanos Atlântico e Pacífico. Correlações simples indicam conexões mais significativas entre modos do Pacífico e as regiões do Sertão e Alto Sertão, decrescendo em direção ao Litoral. Por outro lado, anomalias das águas no oceano Atlântico apresentam influência quase homogênea em grande parte do Estado da Paraíba, com maior sinal na faixa leste adjacente. Observa-se ainda, que classificações climáticas de forma seriada, com o processamento dos percentuais de cada tipo de clima e distribuição temporal, representa um método mais realista de análise do clima, haja vista que a partir de normais climatológicas, descreve-se uma condição média do clima local ou regional. Due to the large area included in the semiarid delimitation of Brazil, more than 86% of its territory, Paraíba is one of the Brazilian states where aridity is more severe. The availability of water is a decisive process in terms of its effective environmental, social and economic development, which is closely dependent on the prevailing climatic conditions. In this context, the need for the quantification of indexes that have as purpose, the climatic characterization of a given location, in order to better suit the prevailing climate classes, emerges. Thus, the present study aims to weave past scenarios of spatial and temporal variability of climatic indexes. Therefore, climatic indexes are calculated from normal climatological and serial annual data for a period of fifty years to twenty pluviometric stations carefully selected and distributed throughout the state of Paraíba. The methodology proposed by Thornthwaite (1948) and the aridity index applied by the United Nations Environment Program - UNEP (1992) are taken into account. As a subsidy, the conceptual application of spectral methods with the subsequent application of the wavelet analysis to the serial climatic indexes is used. It turns out that even if different methodologies produce different climatic classifications for the same place and period of time, the development of interannual and interdecadal variabilities are extremely similar, recommending the same agents as cause of these variabilities. Even so, the UNEP aridity index is less critical for climate classifications than for the use of the Thornthwaite indices, showing less aridity. The interdecadal variability is significantly more apparent than the interannual variability, with a marked predominance in the 11-year scale, interacting with smaller scales of 5, 3.5 and 2.5 years, which tend to follow the main behaviors of the thermal variability in the basins of the Atlantic and Pacific oceans. Simple correlations indicate more significant connections between Pacific modes and the regions of Sertão and Alto Sertão, decreasing toward the coast. On the other hand, water anomalies in the Atlantic Ocean show almost homogeneous influence in much of the state of Paraíba, with a greater signal in the adjacent eastern range. It is also observed that climatic classifications in a serial way, with the processing of the percentages of each type of climate and temporal distribution, represents a more realistic method of climate analysis, given that, based on climatological normals, it describes an average local condition or regional climate.

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Sick, Benjamin [Verfasser], and Manfred [Akademischer Betreuer] Joswig. "Temporal and spectral pattern recognition for detection and combined network and array waveform coherence analysis for location of seismic events / Benjamin Sick ; Betreuer: Manfred Joswig." Stuttgart : Universitätsbibliothek der Universität Stuttgart, 2017. http://d-nb.info/1136319492/34.

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Espejo, Hermosa Antonio. "Variabilidad espacial y temporal del recurso surf: metodología y resultados." Doctoral thesis, Universidad de Cantabria, 2011. http://hdl.handle.net/10803/39302.

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Esta tesis presenta el primer estudio científico acerca de la ocurrencia de condiciones favorables para el surf en las escalas global y regional (en este caso en el Mar Cantábrico). Para ello han sido empleadas bases de datos de reanálisis atmosféricos y de oleaje previamente calibrados, los cuales permiten estimar la calidad de las condiciones y la consistencia (días de buenas condiciones de surf) la cual es la principal característica en la disponibilidad de recurso (Lazarow et al., 2007). Los valores medios obtenidos muestran una alta relación con el patrón general de circulación atmosférica y con las características de propagación de los oleajes tipo swell y, por lo tanto, con las variaciones estacionales de los mismos. El estudio de la variabilidad estacional ha sido investigado relacionando la consistencia mensual con diferentes índices climáticos como el SOI (Southern Oscillation Index) o la NAO (North Atlantic Oscillation) entre otros, mostrando valores altos de correlación. El análisis de las tendencias en el largo plazo muestra un incremento generalizado en las costas con orientación oeste (ej. 20 horas/año en California), lo cual coincide con un incremento de la actividad extratropical durante el periodo de tiempo analizado. En la escala regional han sido empleadas técnicas de regionalización para obtener campos de oleaje y viento de alta resolución con el objetivo de mejorar la estima de la calidad de las condiciones de surf. Para ello, han sido calculadas la dispersión frecuencial y direccional del espectro de oleaje mejorando la estima actual de la calidad, la cual es altamente dependiente de los procesos de propagación del oleaje por aguas someras. La variabilidad climática en esta escala ha sido estudiada por medio de técnicas de clasificación de la atmósfera que permiten obtener patrones preferenciales de variabilidad en diferentes escalas temporales: tipos de tiempo (3 días) y patrones climáticos (1 mes). Estas técnicas permiten relacionar unívocamente un estado de la atmosfera con una distribución específica de la energía del oleaje en el dominio de las frecuencias y direcciones. Esta metodología permite además analizar la variabilidad en la forma espectral debida al cambio climático o la variabilidad climática natural. This thesis presents the firs scientific study of the surf conditions occurrence at a global and a regional scale (herein Cantabrian Sea). Calibrated wave and wind hindcast data bases have used as the ground true estimating surf quality and consistency (days of good surfing conditions) which is the most striking feature in surf resource availability (Lazarow et al., 2007). Mean consistency values are calculated finding spatial patterns highly related with the general circulation scheme and swell traveling properties and thus seasonality. Controls of inter-annual variability are investigated by comparing occurrence values with global and regional climate patterns. Southern Oscillation Index (SOI), North Atlantic Oscillation (NAO) between others, have been related to surf occurrence, showing a great influence at both, global and regional scales. Analysis of long term trends shows an increase in the probability of surfable events over the west facing coasts on the planet (e.g. 20 hours/year in California coasts), according with previous studies which indicate increased extra-tropical storminess during the past few years. Moreover, downscaling techniques have been employed obtaining high resolution wave and wind fields in order to asses surf quality in a regional scale. At this scale, spectral directional and frequency spreading have been also determined improving the current estimation of the surf quality, which is highly related to the wave shallow water processes. Clustering statistics techniques have been applied to sea level pressure over the North Atlantic obtaining leading patterns of weather (3 days) and climate variability (1 month) corresponding to AO (Arctic Oscillation), NAO or EA (East Atlantic Oscillation) atmospheric states. These techniques allow univocal relating some specific state of the atmosphere with one wave energy distribution through frequencies and directions domain, including high frequency energy coming from local winds. In addition the proposed methodology makes possible analyzing spectral variability due to climate change or natural climatic variability.

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Zhang, Xuelu. "Les tons lexicaux du chinois mandarin en voix modale et en voix chuchotée." Thesis, Strasbourg, 2017. http://www.theses.fr/2017STRAC041/document.

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Notre recherche est une contribution à l’étude des indices acoustiques secondaires des tons lexicaux en mandarin, comparant les données recueillies en parole modale avec celles obtenues en parole chuchotée. Selon la littérature, ces indices devraient se présenter en tant qu’un ensemble d’attributs dans les dimensions acoustiques du spectre, outre que dans la fréquence fondamentale. Nous avons analysé des attributs temporels, des attributs au niveau de l’intensité, des attributs spectraux, ainsi que leur corrélation avec les tons. Les résultats montrent que certains paramètres temporels et la quatrième résonance du spectre sont étroitement liés au ton. Leurs rapports dépendent de la caractéristique intrinsèque de la voyelle qui porte le ton (équivalente de la rime dans notre recherche) Our research is a contribution to studies on secondary acoustic cues in Mandarin tone identification, by comparing acoustic data collected in modal speech and in whispered speech. According to the literature on the same issue, theses cues could be found in acoustic dimensions other than in the fundamental frequency, as a set of attributes. We have analyzed these attributes in the temporal domain, at the intensity level and in the spectrum, as well as their relations with tones. Our results show that some temporal parameters and the fourth resonance in the spectrum are very closely related to tones. These relations are dependent on the intrinsic characteristics of the vowel that carries the tone (which is equivalent to the rime in our research)

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Evaristo, Ronaldo Mendes. "Métodos de reamostragem de séries temporais baseados em wavelets." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/3/3142/tde-11082010-152356/.

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Neste texto são revisados métodos de reamostragem de séries temporais discretas baseados em wavelets, como alternativas as abordagens clássicas, feitas nos domínios do tempo e da frequência. Tais métodos, conhecidos na literatura como wavestrap e wavestrapping fazem uso, respectivamente, das transformadas wavelet discreta (DWT) e wavelet packet discreta (DWPT). Existem poucos resultados sobre a aplicação da DWPT, de forma que este texto pode ser considerado uma contribuição. Aqui mostra-se também, a superioridade do wavestrapping sobre o wavestrap quando aplicados na estimação da densidade espectral de potência de séries temporais sintéticas geradas a partir de modelos autoregressivos. Tais séries possuem uma particularidade interessante que são picos, geralmente acentuados, em sua reapresentação espectral, de tal forma que grande parte dos métodos clássicos de reamostragem apresentam resultados viesados quando aplicados a estes casos. This paper reviews resampling methods based on wavelets as an alternative to the classic approaches which are, made in the time and frequency domains. These methods, known in the literature as wavestrap and wavestrapping, make use, respectively, of the discrete wavelet transform (DWT) and of the discrete wavelet packet transform (DWPT). Since only few results are avaliable when the DWPT is applied, this text can be considered a contribution to the subject. Here we, also show the superiority of wavestrapping over wavestrap when they are applied to the estimation of power spectral densities of the synthetic time series generated from autoregressive models. These series have an interesting feature that are sharp peaks in their spectral representation, so that most of the traditional methods of resampling lead to biased results.

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Muñoz, Julián Antonio Villamarín. "Estimativa dos parâmetros acústicos em uma mistura de líquidos imiscíveis durante o processo de separação de fases." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/82/82131/tde-13022008-113511/.

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Esta pesquisa estuda a evolução temporal dos parâmetros de propagação acústica de uma mistura de líquidos imiscíveis considerada como emulsão instável durante o processo de separação de suas fases. O principal objetivo neste trabalho é estudar o comportamento não linear de materiais que variam sua não homogeneidade quando são submetidos a um campo acústico. O estudo é baseado na teoria de análise espectral de ecos de ultra-som para entender o processo físico de interação da onda - emulsão. A emulsão bifásica que tem sido analisada neste estudo é composta principlamente por um óleo mineral A e um óleo vegetal B. A metodologia é baseada na análise tempo freqüência de ecos e sinais de backscattering de ultra-som com uma freqüência central de 5 MHz e uma largura de banda de 8 MHz @ - 3dB. A velocidade média de propagação acústica para a mistura liquida foi estimada em 1354 m/s. O coeficiente de atenuação foi calculado para cada fase separada e se obtiveram os seguintes resultados: 0.82 dB/cm - MHz para o óleo A e 0.59 dB/cm - MHz para o óleo B. O parâmetro B/A avaliado para cada fase separada foi de: 8.43 para óleo A e 10.74 para o óleo B. A variação dos parâmetros acústicos descreveram a evolução da emulsão no tempo mediante o decremento das curvas de atenuação, B/A e IBC. A velocidade de propagação não forneceu informações relevantes a respeito do processo de separação das fases, devido a sua variação mínima. A percentagem média de variação dos parâmetros acústicos durante o processo dinâmico de separação das fases da emulsão foi de 1.39% para a velocidade de propagação, 46.9 para B e 51% para B/A. Espera-se que o estudo possa ser extrapolado para o melhor entendimento da interação de ondas de ultra-som em meios não homogêneos e variantes no tempo. This research studies the time evolution of acoustic propagation parameters of a mixture of inmiscible liquids considerated as unstable emulsion during the separation process into its original phases. The main aspect of this work is to deal with the behavior of nonlinear, nonhomogeneous and time-varying media when they are submitted in an acoustic field. The study is based on spectral analysis theory of ultrasound-backscattered echoes for understanding of physical process of the wave-emulsion interaction. The biphasic emulsion, which has been analyzed during this study, is composed by a mineral oil (phase A) and vegetable oil (phase B). The methodology was based on time-frequency analysis of backscattered broadband ultrasound echo at center frequency of 5 MHz and bandwidth of 8 MHz @ -3dB using an ultrasound system in pulse-echo mode. The mean acoustic propagation velocity for the mixture liquid was estimated in 1354 m/s. The attenuation coefficients were calculated for each separated phase resulting in 0.82 dB/cm-MHz to phase A and 0.59 dB/cm-MHz to phase B. The B/A parameter have been evaluated resulting in 8.43 (phase A) and 10.74 (phase B). The acoustic parameters variation allowed identified different emulsification state inside emulsion. The time evolution for the emulsion was described throught the decrease of attenuation, B/A and IBC. The acoustic propagation velocity don\'t provide relevant information about the phases separation process, because it showed a minimal variation. The mean percentage variation for the time evolution of the acoustic parameters was 1.39% to the acoustic propagation velocity, 46.9% to B and 51% to B/A. We hope that observations can be extrapolated aiming a better understanding of ultrasonic waves interaction in non-homogeneous time-varying medium.

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Gerhartz, Cody J. "Temporal Variations in The Circumstellar Disks of Be Stars from Analysis of Optical and IR Line Profiles." University of Toledo / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1501602656319988.

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19

DiGirolamo, Paul A. "A comparison of change detection methods in an urban environment using LANDSAT TM and ETM+ satellite imagery a multi-temporal, multi-spectral analysis of Gwinnett County, GA 1991-2000 /." unrestricted, 2005. http://etd.gsu.edu/theses/available/etd-07242006-110800/.

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Thesis (M.A.)--Georgia State University, 2005. Title from title screen. Zhi-Yong Yin, committee chair; Paul Knapp, Truman Hartshorn, committee members. Electronic text (135 p. : col. ill., col. maps)) : digital, PDF file. Description based on contents viewed Aug. 2, 2007. Includes bibliographical references (p. 125-133).

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DiGirolamo, Paul Alrik. "A Comparison of Change Detection Methods in an Urban Environment Using LANDSAT TM and ETM+ Satellite Imagery: A Multi-Temporal, Multi-Spectral Analysis of Gwinnett County, GA 1991-2000." Digital Archive @ GSU, 2006. http://digitalarchive.gsu.edu/anthro_theses/18.

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Land cover change detection in urban areas provides valuable data on loss of forest and agricultural land to residential and commercial development. Using Landsat 5 Thematic Mapper (1991) and Landsat 7 ETM+ (2000) imagery of Gwinnett County, GA, change images were obtained using image differencing of Normalized Difference Vegetation Index (NDVI), principal components analysis (PCA), and Tasseled Cap-transformed images. Ground truthing and accuracy assessment determined that land cover change detection using the NDVI and Tasseled Cap image transformation methods performed best in the study area, while PCA performed the worst of the three methods assessed. Analyses on vegetative and vegetation changes from 1991- 2000 revealed that these methods perform well for detecting changes in vegetation and/or vegetative characteristics but do not always correspond with changes in land use. Gwinnett County lost an estimated 13,500 hectares of vegetation cover during the study period to urban sprawl, with the majority of the loss coming from forested areas.

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21

Suptille, Mickaël. "Caractérisation temporelle et spectrale de champs instationnaires non gaussiens : application aux hydroliennes en milieu marin." Thesis, Rouen, INSA, 2015. http://www.theses.fr/2015ISAM0006.

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L’environnement opérationnel des pales et des structures porteuses des hydroliennes est de nature incertaine, compte tenu de la variabilité de l’écoulement (turbulence, sillage, houle, courants. . .). Ces éléments structuraux subissent donc des états de contraintes multiaxiaux complexes avec des fortes variations temporelles à caractère aléatoire. Ainsi, le dimensionnement basé sur des critères statiques déterministes apparaît insuffisant pour tenir compte de la complexité de l’histoire du chargement mécanique et de sa variabilité.Ce travail vise à établir des méthodes de dimensionnement adaptées à cette situation, pour la conception de structures hydroliennes aux risques et aux coûts maîtrisés. La démarche adoptée repose sur la description de l’écoulement et de ses grandeurs statistiques, afin de caractériser les efforts exercés sur l’hydrolienne et les contraintes mécaniques extrêmes en pied de pale The operating environment of tidal turbines blades and body is uncertain, due to the flow variability (turbulence,wake, tide, streams...). These structural elements then undergo strongly time-varying complex multi-axial random stress states. A design based on static and deterministic criteria thus appears insufficient to take the complexity and the variability of the mechanical loading into account. This work aims at setting sizing methods that are adapted to this situation, in order to design tidal turbines with mastered risks and costs. The proposed method lies on a statistical description of the flow, in order to characterize the load of the turbine and the extreme mechanical stresses at the blade foot

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22

Brandelero, Catize. "Espectrorradiometria do visível e infravermelho próximo em povoamento de Eucalyptus grandis W. Hill ex Maiden." Universidade Federal de Santa Maria, 2010. http://repositorio.ufsm.br/handle/1/3731.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior Aiming to develop studies relating laboratory spectroradiometry with macro and micronutrients contents of vegetative materials of forest populations of Eucalyptus grandis W Hill ex Maiden, of different ages, an experimental área was selected for the study at the Fundação Estadual de Pesquisas Agropecuárias FEPAGRO FLORESTAS, at Santa Maria, Rio Grande do Sul, Brazil. Departing from the purpose of studying the spectral behaviour, the specific objectives were: 1) to evaluate the leaves of E. grandis contents of macro and micronutrients, in the four climatic seasons, under differente types of soil managements; 2) to evaluate the leaves of E. grandis spectral behaviour including the waveband of 475 to 980ηm and approach the interaction between: climatic seasonal periods, different soil managements and the cardinal points locations of the sampled trees; 3) evaluate the nutritional status of E. grandis young trees leaves through leaf analyses and spectroradiometry, and generate models capable to estimate macro and micronutrients from reflectancy data. Results indicate that the E. grandis population, of 44 months old, shows deficiencies of P, S, B; Cu and Mn showed high contents; N was the only nutrient showing significant differences; there is no significant differences between climatic seasons. For the E. grandis population of 20 months old, variations observed in the nutrients contents were equal to those of the former area; the winter sesason showed a differente behaviour from the other climatic seasons. For the different soil managements, the macro and micronutrients did not vary significantly. Evaluating the reflectancy data for the leaves of E. grandis, of 20 months old, it was concluded that: 1) the summer and spring seasons statistically interfered on the reflectancy; 2) samples of vegetative material may be collected independently of the type of soil management; and, 3) the spectral wavebands that better expresses the vegetation behaviour were the 12, 8, 7 and 3; and, 4) the evaluation of points where the leaves were sampled (East, West, North, South and central) in the no-tillage soil management treatment indicated that: a) sampling of vegetative material should be done separating the central part of the bordering population; and, b) the waveband that better characterized the spectral response of the vegetation was that of number eight. Analysis of the main components indicated the 8, 11 na 12 wavebands as responsible for a total of 98.10% of the reflectancy values under study. The elements P and K showed low adjusted correlation coefficients while generating models considering the elements as dependent variables from reflectancy and climatic seaso;n interacting with wavelengths; the r2aj. values for the remaining elements varied from moderate to high. Com o intuito de desenvolver estudos relacionando a espectrorradiometria de laboratório com os teores de macro e micronutrientes em materiais vegetativos de povoamentos florestais de Eucalyptus grandis W. Hill ex Maiden, com diferentes idades, uma área experimental foi selecionada para estudo na Fundação Estadual de Pesquisas Agropecuárias FEPAGRO FLORESTAS, Santa Maria, Rio Grande do Sul, Brasil. A partir da proposta de estudar o comportamento espectral, os objetivos específicos foram: 1) avaliar os teores de macro e micronutrientes de folhas de E. grandis nas quatro estações climáticas do ano em diferentes tipos de preparo de solo; 2) avaliar o comportamento espectral de folhas de Eucalyptus grandis abrangendo o intervalo de comprimento de onda de 475 a 980ηm, e abordar as interações: períodos sazonais, preparos de solo e a localização cardeal das árvores amostradas; 3) avaliar o estado nutricional de folhas de plantas jovens de E. grandis por análise foliar e espectrorradiometria e gerar modelos capazes de estimar os teores de macro e micronutrientes a partir de dados de reflectância. Os resultados indicam que o povoamento de E. grandis, com 44 meses de idade, apresenta deficiência de P, S e B; Cu e Mn apresentam teores elevados; N é o único nutriente que apresenta diferença significativa; entre as estações climáticas não existem diferenças significativas. Para o povoamento de E. grandis com 20 meses, as variações obtidas para os teores de nutrientes foram iguais as da área anterior; a estação inverno apresentou comportamento diferenciado das demais estações. Para os diferentes preparos de solo os macro e micronutrientes, não variaram significativamente. Avaliando os dados de reflectância de folhas de E. grandis, com 20 meses de idade, conclui-se que: 1) as estações verão e primavera interferiram estatisticamente na reflectância; 2) as amostras de material vegetativo podem ser coletadas independentemente do tipo de manejo do solo; 3) as bandas espectrais que melhor expressaram o comportamento da vegetação, foram as bandas 12, 8, 7 e 3; e, 4) a avaliação das posições em que as folhas foram coletas (Leste, Oeste, Norte, Sul e central) no tratamento com preparo de solo plantio direto indicaram que: a) as coletas de material vegetativo devem ser realizadas separando a parte central do povoamento da bordadura; e, b) a banda que melhor caracterizou a resposta espectral dessa vegetação foi a de número oito. A análise de componentes principais indicou as bandas 8, 11 e 12, como responsáveis por um total de 98,10% dos valores de reflectância em estudo. Ao gerar modelos considerando os elementos como variáveis dependentes da reflectância e estação do ano interagindo com comprimentos de onda, os elementos P e K apresentaram os valores dos coeficientes de correlação ajustados baixos; os valores de r2aj. dos demais elementos variaram de moderados a altos.

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23

Havlíková, Ivana. "Dynamická analýza konstrukce zatížené seismickým zatížením." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2012. http://www.nusl.cz/ntk/nusl-225730.

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The purpose of my master’s thesis is the solution steel hall with concrete columns, that is loaded by an earthquake. This simulation program was used RFEM. To calculate was used the spectral and temporal analysis, and that on models of structures with several combinations of materials. The analysis was performed for both the general direction of the earthquake, so for combinations of directions according to standard procedures in EC8.

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24

Muscat, Laurent. "Coupling of time integration schemes for compressible unsteady flows." Thesis, Toulouse, INPT, 2019. http://www.theses.fr/2019INPT0010/document.

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Dans ce travail, on s'intéresse au développement d'une méthode hybride qui couple spatialement les schémas d'intégration temporelle explicite et implicite. Afin de répondre aux contraintes du solveur industriel FLUSEPA, les schémas explicite Heun et implicite Crank-Nicolson ont été hybridés via un paramètre de transition : l'approche mise en place est appelée schéma AION. Cette dernière est étudiée en détails avec une attention particulière sur son comportement spectral et sa capacité à maintenir l'ordre de précision. On montre que le traitement hybride a d'intéressants comportements dissipatif et dispersif tout en empêchant la réflexion d'ondes parasites et en maintenant la précision attendue. De plus, l'approche hybride est validée sur plusieurs cas académiques à la fois pour les flux convectifs et pour les flux diffusifs. Et comme espéré, la méthode est plus intéressante en terme de temps de calcul que les méthodes standards d'intégration temporelle. Pour l'extension de cette approche à la méthode temporelle adaptative présente dans FLUSEPA, il a été nécessaire d'améliorer le traitement qui permet à la méthode d’être conservative tout en obtenant des propriétés spectrales acceptables. Finalement l'approche hybride a été aussi étendue pour la modélisation RANS/LES de la turbulence avec des temps de calcul intéressants tout en capturant la physique de l'écoulement This work deals with the design of a hybrid time integrator that couples spatially explicit and implicit time integrators. In order to cope with the industrial solver of Ariane Group called FLUSEPA, the explicit scheme of Heun and the implicit scheme of Crank-Nicolson are hybridized using the transition parameter : the whole technique is called AION time integration. The latter is studied into details with special focus on spectral behaviour and on its ability to keep the accuracy. It is shown that the hybrid technique has interesting dissipation and dispersion properties while maintaining precision and avoiding spurious waves. Moreover, this hybrid approach is validated on several academic test cases for both convective and diffusive fluxes. And as expected the method is more interesting in term of computational time than standard time integrators. For the extension of this hybrid approach to the temporal adaptive method implemented in FLUSEPA, it was necessary to improve some treatments in order to maintain conservation and acceptable spectral properties. Finally the hybrid time integration was also applied to a RANS/LES turbulent test case with interesting computational time while capturing the flow physics

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25

Xu, Shulan. "Effect of Uncertainty of Rock Properties on Radionuclide Transport by Groundwater : Implications for Performance Assessments of the Repository of Spent Nuclear Fuel in Heterogeneous Bedrock." Doctoral thesis, Uppsala University, Department of Earth Sciences, 2000. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-544.

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The overall objective of the current study is to develop a quantitative understanding of the effects of spatial variability in physical and geochemical properties of crystalline rock on the migration of radionuclides along a single fracture in bedrock. A stochastic model was developed to describe the transport of solutes in fractured rock. The model describes the migration of radionuclides along a one-dimensional path and includes the transversal diffusion into the rock matrix and sorption kinetics. By using a Lagrangian method of description we can extend the model to the description of a two-dimensional transport problem in single fractures. This study presents the first analysis of the impact of heterogeneous mass transfer on the transport of radionuclides in rock fractures, where most of the relevant rock properties such as aperture, porosity, effective diffusivity, sorption capacity and maximum diffusion depth are defined as being spatially random. The stochastic analysis performed here reflects the uncertainty in our knowledge of the properties associated with a discrete sampling technique in site investigations.Geostatistics of the main parameters was determined experimentally on a large number of rock samples taken from the Swedish crystalline basement. The knowledge of the covariance functions of the main rock properties is then used as a basis for a stochastic analysis. By combining the small perturbation approach with the spectral method the problem could be solved in terms of closed form solutions for the central temporal moments of the residence time probability density function. In order to be able to distinguish between the effects of various mechanisms from the effects of heterogeneity on the migration of radionuclides, it was necessary to perform independent studies of the effect of the variation of the dispersion coefficient on the aspect ratio of a rectangular flow section and the effect of adsorption kinetics on the migration. Finally, the effect of the heterogeneous rock properties on the solute transport observed in a limited number of migration experiments corresponds fairly well to the theoretical effect expected on the basis of the experimentally determined auto-covariance functions.

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26

Lima, Junior Afonso Valau de. "APLICAÇÃO E PERFORMANCE DA ANÁLISE DE INTERVENÇÃO EM SÉRIES DE EMISSÃO DE GASES POLUENTES NA CIDADE DO MÉXICO." Universidade Federal de Santa Maria, 2016. http://repositorio.ufsm.br/handle/1/8390.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior This research aims to evaluate the performance of time-series models together with the use of analysis, when the time for action is determined by visual inspection of the series or the spectral analysis, greenhouse gas emission data. In carrying out this research were considered data from the time series of the measurement of ozone gas (O3), nitrogen dioxide (NO2), carbon monoxide (CO) and sulfur dioxide (SO2), understood in January 1986 to December 2014, referring to the first day of each month, totaling 348 observations. The models were performed pre-analysis, using spectral analysis to determine the period in which the intervention must be done, show better performance considering the AIC and BIC criteria. Indicating that whenever possible to use this tool as an aid for modeling time series who need intervention. Esta pesquisa tem como objetivo avaliar o desempenho dos modelos de séries temporais conjuntamente com a análise de intervenção, quando o instante de intervenção é determinado pela inspeção visual da série ou pela análise espectral em dados de emissão de gases poluentes. Para a execução desta pesquisa foram considerados os dados da série histórica da medição dos gases ozônio (O3), dióxido de nitrogênio (NO2), monóxido de carbono (CO) e dióxido de enxofre (SO2), compreendidos no período de janeiro de 1986 a dezembro de 2014, referente ao primeiro dia de cada mês, totalizando 348 observações. Os modelos em que realizou-se a pré-análise, utilizando-se da análise espectral, para determinar o período em que análise de intervenção foi realizada, apresentou melhor desempenho considerando-se os critérios AIC e BIC, indicando sempre que possível utilizar essa ferramenta como auxiliar para modelagem de séries temporais.

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27

Correa, Marco Antonio. "ANÁLISE DAS OSCILAÇÕES DAS CORRENTES OBSERVADAS NA BAÍA DE ILHA GRANDE (RJ)." Universidade de São Paulo, 1994. http://www.teses.usp.br/teses/disponiveis/21/21132/tde-19032009-153439/.

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Series temporais de correntes, vento (força e direção), temperatura e salinidade, com duração de 24h, obtidas em 5 estações na Baia da Ilha Grande (rj), de 3-29/01/82, foram analisadas. As medições de corrente foram feitas a5, 12 e 20m, a cada 5min e a 2m acima do fundo, a cada 12min; temperatura e salinidade em cinco profundidades a cada 3h e vento a cada 1h. Foram utilizadas análises de series temporais através dos métodos diretos (periodograma) e indireto para as estimativas espectrais alisadas, bem como as equações hidrodinâmicas na determinação dos períodos. Foram utilizados os testes: ruído branco e fisher-whittle, a análise dos espectros rotatórios e a análise cruzada entre vento e corrente, ao longo de três camadas: superfície intermediaria e de fundo. Foram determinadas oscilações de 4,8h e identificadas como seiches internos e detectadas oscilações com período de 3,4h associadas à ressonância com o vento. Em todo o sistema da baia o período de 6h mostrou-se significativo, correspondendo à oscilação natural da baia. Foram detectadas oscilações de alta freqüência 11 e 20min, 20cm/s eventualmente associadas a vórtices e meandros da corrente. Água subtropical na camada de fundo da baia Temporal series of currents, wind, water temperature and salinity, obtained from 5 oceanographic stations located in and around Ilha Grande Bay (RJ, Brazil), from January 23 to 29, 1982, were analyzed. AlI series have 24 hours. Currents measu¬rements were dione at depths of 5, 12, 20 m (every 5 minutes) and near the bottom (every 12 minutes). Temperature and salinity data were taken from 5 depths every 3 hours for each, while the wind was measured every hour. The present work was per¬formed in order to investigate short-period oscillations present in the region, related to density stratification and to the features of the basin, as well as to describe the circulation patterns and currents variations during one day interval. Two kinds of analysis were used: temporal series analysis, using statistical and spectral methods, and calculations by hydrodynamic motion equations. In temporal series analysis the direct (periodogram) and indirect methods were used for the spectral estimations. White-noise, Fisher- Whittle tests and rotational spectra analysis were also applied, besides the cross spectrum analysis for the data about winds and currents. The results indicate an intense and unidirectional circulation in the layer above 5 meters, from the western to the eastern portion of the Bay, through Central Channel. In this layer, on the eastern sea-opening side, a flux toward the Bay was observed. These motions, within 5 meters depth, were attributed to a circulation generated by a horizontal density difference between oceanic and inshore waters, with few contribution from tides and winds. At intermediate and near bottom layers, a horizontal homogeneity was observed and, consequent1y, smaller horizontal density gradients were detected. This way, circulation caused by tides was stronger than the movements forced by su¬perficial layers. Resultant bottom currents, observed at the Bay openings, led to the open-sea. At Central Channel, 4.8 h period oscillations were detected, and identified as internal seiches. In the eastern Portion, 3.4 hour period oscillations were detected, related to wind resonance. In alI the bay-system, the 6.0 hour period was significant, corresponding to the bay\'s natural oscillation. The study area presented a density stratification in two layers, with a single water type filling alI the portion below the 20 meters. This water, with characteristics of Subtropical Water, occupied the bottom layer due to an upwelling process produced by the dynamics of currents and winds in the continental shelf . In the two stations located off the bay, the wind and currents observations support this upwelling hypothesis.

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28

Mohan, Anusha. "Neural Correlates of Spectral, Temporal and Spectro-temporal Modulation." Scholar Commons, 2014. https://scholarcommons.usf.edu/etd/5078.

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Natural sounds are characterized by the distribution of acoustic power over different frequency regions and/or time. This is termed spectral, temporal or spectro-temporal modulation. The auditory system is equipped with banks of filters tuned to different spectral, temporal and spectro-temporal modulation frequencies (SM, TM, STM). The sensitivity of the peripheral system to these modulations can be measured by undertaking a linear systems approach. In addition to understanding the psychophysical sensitivity, studying the neural patterns of their processing is also critical. The current study is an attempt to understand the relationship between the behavioral and neural correlates of spectral, temporal and spectro-temporal processing in ten normal hearing subjects (age range 21-27 years; mean = 23.7 years). In the behavioral experiment, sensitivity to SM, TM and STM frequencies was estimated using a 3-interval, 3-alternative, forced-choice paradigm with a 3-down-1-up tracking algorithm. In the electrophysiological experiment, Electroencephalographs (EEGs) were recorded in a change-detection paradigm in response to the same set of modulation stimuli used in the behavioral experiment presented at 20 dB sensation level (SL). The EEG data were analyzed to determine the global field power and latencies of the N1and P2 components and the amplitude of the N1-P2 complex. Although an overall parietal dominance was observed for all of the components, the N1-P2 complex was strongly lateralized to the right hemisphere in the frontal region, but the hemispheric asymmetry decreased at central and parietal regions. A highly significant but weak to moderate negative correlation between individual behavioral thresholds and N1-P2 amplitudes was observed, and this relationship also was observed when behavioral spectro-temporal transfer functions and N1-P2 amplitude transfer functions were examined together. Thus the current project reveals that a relationship exists between the behavioral measures and neural correlates and gives us hope to work towards establishing this relationship.

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29

Hoglund, Evelyn M. "Spectral and temporal integration of brief tones." Columbus, Ohio : Ohio State University, 2007. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1186528279.

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30

Reising, Monica. "Modeling and discrimination for spectral-temporal data." [Ames, Iowa : Iowa State University], 2009.

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31

Aiken, Steven James. "Effects of spectral asynchrony and spectral degradation on consonant perception, implications for spectral and temporal speech cues." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0017/MQ58011.pdf.

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32

Collinson, James Stuart. "Spectral and temporal studies of supermassive black holes." Thesis, Durham University, 2016. http://etheses.dur.ac.uk/11814/.

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In this thesis, I present analysis and interpretation of the multiwavelength spectra and variability of Active Galactic Nuclei (AGN). The most luminous sustained sources in the Universe, these powerful objects are consistent with being the result of gas accretion on to central galactic supermassive black holes. Due to their compact sizes, the inner regions of AGN cannot be spatially resolved by conventional means, so we must instead use spectroscopy and temporal monitoring to determine their composition and structure. I undertake a number of studies of the spectral energy distributions (SEDs) of AGN, using data from infrared-X-ray bands and employing a range of numerical models. Results from SED modelling of 11 moderate redshift (1.5 < z < 2.2) AGN are presented, in which there is a selection bias towards nuclei with cooler accretion discs. I find that the peak of the SED is sampled by our data for 5/11 objects, thereby breaking several of the model degeneracies that affected previous studies. This results in stronger constraints on the physical processes at work in these AGN, and provides a powerful tool with which I examine and discuss the relationships between the various radiating components, including those of the emission line regions, dusty torus and host galaxy. I then explore the nature of four 'hypervariable' AGN, for which the origin of their extreme variability is currently unknown. Through an investigation of their SEDs, I find that either an accretion rate change, or gravitational microlensing by a star in a foreground galaxy, are energetically consistent with the data. The new insights provided by this work lead me to suggest several worthwhile routes for the future development of research in these areas. With the next generation of telescopes, satellites and surveys on the horizon, it will be possible to build on my results, to further our understanding of AGN.

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33

Borgonovo, Luis. "Spectral and Temporal Studies of Gamma-Ray Bursts." Doctoral thesis, Stockholm : Department of Astronomy, Stockholm University, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-6793.

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34

Bamatraf, Abdurhman Mohamed. "Temporal and spatial relationships of canopy spectral measurements." Diss., The University of Arizona, 1986. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu_e9791_1986_25_sip1_w.pdf&type=application/pdf.

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35

Tarr, Eric William. "Processing Perceptually Important Temporal and Spectral Characteristics of Speech." The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1376913300.

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36

Brulé, Thibault. "Spectral and temporal distribution of biomolecules by Dynamic SERS." Thesis, Dijon, 2014. http://www.theses.fr/2014DIJOS037/document.

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Dans cette thèse, la définition du SERS en tant que biocapteur a été testée et une nouvelle approche a été développée. Ainsi, concernant la quantification, il est montré que le SERS peut-être un outil très efficace. Concernant la sélectivité, la qualité spectrale a été améliorée. Une excellente limite de détection associée à l’approche statistique et dynamique permet une très bonne sensibilité (inférieure au nanomolaire). Cette approche permet également une grande reproductibilité du capteur dans le temps. Ainsi, alors que le SERS ne réponds pas forcément bien aux caractéristiques d’un capteur dans son approche classique, dans notre cas le couplage entre un substrat de nanoparticules d’or non fonctionnalisées associé à un système microfluidique, le tout monté sur un microscope confocal pour des études temporelles dynamiques analysées statistiquement a contribué à définir le SERS comme un biocapteur efficace In this thesis, the definition of SERS as a biosensor has been tested and a new approach developed for. Also, in terms of quantification, it has been shown that SERS can be an efficient tool. Concerning the selectivity, the spectral quality was improved. A low limit of detection associated to the statistical and dynamic approach allows a very good sensitivity (under the nanomolar). This approach also enables a high reproducibility in time of the sensor. Thus, as low as SERS does not well answer to the sensor capabilities in a classical approach, in our case the coupling between a non-functionalized GNPs substrate coupled with a microfluidic chip, all mounted on a confocal microscope for temporal dynamic studies statistically analyzed has contributed to define SERS as an efficient biosensor

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Sendov, Hristo. "Variational Spectral Analysis." Thesis, University of Waterloo, 2000. http://hdl.handle.net/10012/1089.

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We present results on smooth and nonsmooth variational properties of {it symmetric} functions of the eigenvalues of a real symmetric matrix argument, as well as {it absolutely symmetric} functions of the singular values of a real rectangular matrix. Such results underpin the theory of optimization problems involving such functions. We answer the question of when a symmetric function of the eigenvalues allows a quadratic expansion around a matrix, and then the stronger question of when it is twice differentiable. We develop simple formulae for the most important nonsmooth subdifferentials of functions depending on the singular values of a real rectangular matrix argument and give several examples. The analysis of the above two classes of functions may be generalized in various larger abstract frameworks. In particular, we investigate how functions depending on the eigenvalues or the singular values of a matrix argument may be viewed as the composition of symmetric functions with the roots of {it hyperbolic polynomials}. We extend the relationship between hyperbolic polynomials and {it self-concordant barriers} (an extremely important class of functions in contemporary interior point methods for convex optimization) by exhibiting a new class of self-concordant barriers obtainable from hyperbolic polynomials.

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Matsuoka, Danilo Hiroshi. "Forecasting brazilian inflation with singular spectrum analysis." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2016. http://hdl.handle.net/10183/147410.

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O objetivo deste artigo é avaliar previsões da inflação brasileira a partir do método não-paramétrico de Análise Espectral Singular (SSA). O exercício de previsão utiliza o esquema de janelas rolantes. Diferentes estratégias de combinação de previsões e procedimentos de seleção de variáveis para métodos multivariados foram contempladas. Para robustez, cinco horizontes de previsão foram utilizados. A avaliação das previsões considera diversos procedimentos e medidas estatísticas para oferecer conclusões confiáveis, incluindo razões de erro quadrático médio de previsão, teste de igualdade condicional de habilidade preditiva, diferenças de erro quadrático médio de previsão cumulativas e Model Confidence Set. Os resultados mostram que o SSA supera consistentemente os métodos competidores. Quase todas as previsões SSA superam os competidores em termos de erro quadrático médio de previsão, e em vários casos, com significância estatística. A análise da porção fora da amostra indica superioridade em performance relativa do SSA, especialmente no período de choque nos preços de energia elétrica. Adicionalmente, métodos SSA sempre foram incluídos no conjunto superior do Model Confidence Set. A falta de estudos relacionados com previsão da inflação brasileira e a relativa escassez de análises de previsões via métodos não-paramétricos ressaltam a relevância deste artigo. Não existem pesquisas na literatura de previsão de inflação brasileira aplicando SSA. Uma das estratégias de combinação de previsões aplicadas neste artigo não é comumente encontrada na literatura, na medida em que envolve combinações de diferentes especificações para cada método de previsão. Adicionalmente, restrições de parâmetros foram impostas nas previsões SSA, uma prática não reportada na literatura. The purpose of this paper is to evaluate Brazilian inflation forecasts produced by the nonparametric method Singular Spectrum Analysis (SSA). This forecasting exercise employs rolling windows scheme. Different strategies of forecast combinations and variable selection procedures for multivariate methods were contemplated. For robustness, five forecast horizons were used. The forecast evaluation considers several statistical measures and procedures to offer reliable conclusions, including mean squared forecast error ratios, tests of equal conditional predictive ability, cumulative square forecast error difference and Model Confidence Set. The results show that SSA consistently outperforms the competitive methods. Almost all SSA forecasts outperforms the competitors in the mean squared forecast error sense, and several with statistical significance. Analysis of the out-of-sample portion indicates relative superior performance of SSA, especially over the period of electricity shock of prices. SSA methods were always included in the superior set of Model Confidence Set procedures. The lack of studies related to Brazilian inflation forecasting and the relative scarcity of nonparametric methods of forecasting analysis highlights the relevance of this paper. There is no research in Brazilian inflation literature applying SSA. One of the forecast combination strategies applied in this paper is not commonly found in the literature, as it involves combinations of different specifications for each forecast method. Additionally, parameter restrictions on SSA forecasts were imposed, a practice which is not reported in the literature.

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Bernardi, Pierre. "Utilisation et Amélioration du Modèle Discret d'Excitation d'un Guide d'Onde Périodique pour la Simulation Pratique du Tube à Onde Progressive en Domaine Temporel." Phd thesis, Université de Provence - Aix-Marseille I, 2011. http://tel.archives-ouvertes.fr/tel-00708349.

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Ce mémoire porte sur la modélisation et la simulation non-stationnaires de l'interaction entre le faisceau d'électrons et l'onde électromagnétique dans les tubes à onde progressives (TOP) à hélice. Le TOP étant un instrument sur-dimensionné, les modèles non-stationnaires généraux sur lesquels se basent la plupart des logiciels commerciaux nécessitent de trop grosses ressources de calcul pour pouvoir être utilisés en un temps raisonnable pour des activités de conception industrielle. Il est donc nécessaire de faire appel à des modèles dits 'spécialisés'. Cette thèse porte sur le modèle discret non-stationnaire d'excitation d'un guide d'onde périodique de S. Kuznetsov. Avant nos travaux, il avait été démontré (N. Ryskin et al., 2007) que ce modèle pouvait s'appliquer aux TOP à cavités couplées dans le cadre d'un modèle à une dimension. Néanmoins, il n'existait alors aucune étude venant confirmer ou infirmer son application aux TOP à hélice. Lors de cette thèse, nous avons démontré, via le développement d'un code à une dimension (HelL-1D), que le modèle discret s'applique convenablement aux TOP à hélice. L'utilisation de ce modèle dans un code à deux dimensions (HelL-2D) a, elle aussi, été effectuée. Enfin, nous avons développé une méthode permettant de contrôler quantitativement les réflexions d'onde aux extrémités de la ligne à retard dans le modèle discret. Cette dernière étude constitue une avancée importante vers la simulation pratique des TOP en utilisant le modèle discret.

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Ludwikow, Marek Jerzy. "Temporal and spectral dynamics of coupled external cavity laser diodes." Thesis, Bangor University, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.540742.

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Rossi, Alfred Vincent III. "Temporal Clustering of Finite Metric Spaces and Spectral k-Clustering." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1500033042082458.

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42

Nastasiu, Dragos-Florin. "Développement de solutions pour l’identification (THID) et l’authentification par des approches non intrusives dans le domaine THz." Electronic Thesis or Diss., Chambéry, 2024. http://www.theses.fr/2024CHAMA007.

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L'imagerie THz est un domaine émergent depuis les avancées technologiques en termes d'émission de rayonnement THz et d'équipement de détection. L'objectif principal de la thèse est de contribuer et d'améliorer les systèmes d'imagerie THz, de la reconstruction et de l'analyse d'images aux tâches de classification d'images. Dans la première partie de la thèse, nous nous attaquons au défi de l'estimation de l'amplitude dans des conditions de bruit idéal et multiplicatif. Le bruit multiplicatif déforme la phase et introduit des artefacts complexes, tels que la perte d'information sur les contours et la dégradation du contraste, qui ne peuvent être éliminés à l'aide des techniques de reconstruction d'image les plus récentes. À cet égard, nous présentons cinq nouvelles méthodes de reconstruction qui exploitent la représentation du diagramme de phase des signaux. Deux de ces méthodes sont basées sur le filtrage du diagramme de phase pour estimer l'amplitude dans les deux conditions. Deux autres méthodes utilisent le concept de déformation temporelle dynamique (DTW) pour augmenter la capacité à modéliser le type de bruit multiplicatif. Enfin, nous exploitons la dynamique de la trajectoire de phase décrite par les courbures pour reconstruire l'image. Parmi le grand nombre de méthodes, nous évaluons tout au long de la thèse que la méthode basée sur les courbures reconstruit efficacement l'image dans des contextes idéaux et bruités. Après une reconstruction efficace de l'image, la deuxième partie de la thèse, nous étudions les méthodes d'analyse et de classification d'images en tenant compte des instabilités des systèmes d'imagerie du monde réel, telles que les translations et les rotations. Dans ce sens, nous proposons d'utiliser des décompositions de paquets d'ondelettes invariantes par rapport à la translation et à la rotation, qui fournissent une représentation unique et optimale d'une image, indépendamment de la translation ou de la rotation de l'image. Sur la base des représentations d'images invariantes, de nouvelles techniques d'extraction de caractéristiques sont introduites, telles que les cadres verticaux, horizontaux, N-directionnels et N-zonaux. En outre, deux structures de caractéristiques sont introduites, qui prennent en compte le partitionnement en fréquence de la décomposition en ondelettes et sont adaptées pour fonctionner avec des réseaux neuronaux graphiques (GNN) et des classificateurs ML classiques tels que les k-voisins les plus proches (k-NN), les machines à vecteurs de support (SVM), etc. Dans l'ensemble, les approches que nous proposons augmentent la précision de tous les classificateurs THz imaging is an emerging field since the technological advances in terms of THz radiation emission and detection equipment. The main objective of the thesis is to contribute and to improve THz imaging systems, from image reconstruction and analysis to image classification tasks. In the first part of the thesis, we tackle the amplitude estimation challenge under ideal and multiplicative noise conditions. The multiplicative noise deforms the phase and introduces complex artefacts, such as contour information loss and contrast degradation, that cannot be eliminated using state-of-the-art image reconstruction techniques. In this regard, we introduce five novel reconstruction methods which exploit the phase diagram representation of signals. Two of the methods are based on phase-diagram match filtering to estimate the amplitude in both conditions. Another two methods use the concept of dynamic time warping (DTW) to increase the capability to model the multiplicative type of noise. Lastly, we exploit the dynamic of the phase trajectory described by the curvatures to reconstruct the image. From the large pool of methods, we evaluate throughout the thesis that the curvature-based method efficiently reconstructs the image in both ideal and noisy contexts. After an efficient image reconstruction, the second part of the thesis, we study image analysis and classification methods considering the instabilities of real-world imaging systems, such as translations and rotations. In this sense, we propose to use translation and rotation invariant wavelet packet decompositions, that provide a unique and optimal representation of an image, regardless if the image is translated or rotated. Based on the invariant image representations, novel feature extraction techniques are introduced such as vertical, horizontal, N-directional and N-zonal frameworks. Additionally, two feature structures are introduced and that consider the frequency partitioning of the wavelet decomposition and are adapted to work with Graph Neural Networks (GNNs) and classic ML classifiers such as k-nearest neighbors (k-NN), support vector machine (SVM), etc. Overall, our proposed approaches increase the accuracy of all classifiers

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Collins, Brian Harris. "Thermal imagery spectral analysis." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1996. http://handle.dtic.mil/100.2/ADA320553.

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Thesis (M.S. in Systems Technology (Space Systems Operations)) Naval Postgraduate School, September 1996. Thesis advisor(s): R.C. Olsen, David Cleary. "September 1996." Includes bibliographical references (p. 159-161). Also available online.

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de, Roos Dolf. "Spectral analysis classification sonars." Thesis, University of Canterbury. Electrical Engineering, 1986. http://hdl.handle.net/10092/5575.

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Sonar target classification based on frequency-domain echo analysis is investigated. Conventional pulsed sonars are compared with continuous transmission frequency modulated (CTFM) sonars, and differences relating to target classification are discussed. A practical technique is introduced which eliminates the blind time inherent in CTFM technology. The value and implications of modelling underwater sonars in air are discussed and illustrated. The relative merits of auditory, visual and computer analysis of echoes are examined, and the effects of using two or more analysis methods simultaneously are investigated. Various statistical techniques for detecting and classifying targets are explored. It is seen that with present hardware limitations, a two-stage echo analysis approach offers the most efficient means of target classification. A novel design for three-section quarter-wavelength transducers is presented and evaluated. Their inherently flat frequency response makes these transducers well suited to broadband applications. The design philosophy and construction details of a Diver's Sonar and an underwater Classification Sonar are given. Sea trials reveal that using the Diver's Sonar, a blind-folded diver can successfully navigate in an unknown environment, and locate and classify targets; using the Classification Sonar, targets may be located and classified using either operators or computer software.

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Hu, Zhihua. "Spectral fatigue analysis techniques." Thesis, University College London (University of London), 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.362446.

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Esch, Thomas [Verfasser]. "Model-based speech enhancement exploiting temporal and spectral dependencies / Thomas Esch." Aachen : Hochschulbibliothek der Rheinisch-Westfälischen Technischen Hochschule Aachen, 2012. http://d-nb.info/1022733702/34.

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Chapman, Ben Howard. "Novel optical fibre based laser sources for spectral and temporal versatility." Thesis, Imperial College London, 2014. http://hdl.handle.net/10044/1/18124.

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As laser amplifiers and oscillators continue to see widespread use in all branches of science and engineering, they continue to develop in terms of operating parameters to keep pace with their applications. Importantly, the temporal and spectral characteristics of laser systems must be carefully tailored to match application requirements. This thesis reports advances in the development of laser systems, based upon optical fibre technology, which demonstrate the flexibility of optical fibre and fibre integrated devices to cover a wide range of temporal and spectral characteristics. First, the principle of spectrally masked phase modulation for short pulse generation is explored. Here, a phase modulator is used to generate a time dependent optical frequency shift, which can be turned into an effective amplitude modulation by the introduction of an optical band pass filter. This method is combined with nonlinear compression techniques based on solitonic propagation in optical fibre to generate optical pulses with duration of a few hundreds of femtoseconds and repetition rates of tens of gigahertz. Increasing the range of wavelengths over with doped fibre amplifier systems will operate requires the development of laser/amplifier systems based on new active dopants. To this end amplifier systems based upon bismuth activated alumosilicate fibre were evaluated. The amplifier stages were then incorporated into a master oscillator power fibre amplifier (MOPFA) scheme, demonstrating the applicability of bismuth doped silica fibre to advanced laser configurations. Finally, the development of a novel laser source for use in fluorescent microscopy is detailed. The source was based on a gain switched diode which is amplified in a two stage Raman fibre amplifier system, subsequently frequency doubled in a periodically poled lithium tantalate crystal. Nonlinearity and optical filtering are exploited to re-shape the output pulse's temporal profile.

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García, Derly Estefanny Gómez. "Modelo empírico linear para previsão da disponibilidade hídrica integrada em função da média móvel da precipitação." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/18/18138/tde-27032017-171327/.

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Variações climáticas podem resultar na entrada insuficiente de água no balanço hídrico de uma região, acarretando em inconsistências relacionadas à outorga de água superficial. O sistema de outorga de água superficial utiliza as vazões percentis (Q7,10, Q90, Q95) para definir a vazão máxima outorgável. No entanto, em períodos de estiagem tais vazões de referência podem não ser suficientes para atender a demanda outorgada, demandando a captação de águas subterrâneas para contrabalançar essa insuficiência hídrica do manancial superficial. Portanto, a outorga dos recursos hídricos deve ocorrer de forma integrada e sustentável, considerando a alteração da descarga do aquífero para o rio devido à captação subterrânea. O objetivo deste trabalho é estimar a disponibilidade hídrica integrada (superficial e subterrânea), por meio de um modelo empírico linear, proposto como função da média móvel da precipitação de períodos anteriores relacionados ao tempo de regulação do aquífero. Técnicas de correlação e espectrais foram empregadas na análise de séries temporais de precipitação (P) e vazão (Q) da bacia hidrográfica do Ribeirão da Onça, com o objetivo de determinar os tempos de resposta de Q em relação a P. A metodologia proposta foi verificada para precipitação e vazões observadas na bacia com área de 65 km2 no período de 2003 a 2014. Os resultados indicam que o aquífero armazena uma parcela de água precipitada e controla o fluxo para o rio, com tempos de regulação de aproximadamente 60 dias para o escoamento subsuperficial e de aproximadamente 2 anos para o escoamento de base. A metodologia também foi testada para duas sub-bacias hidrográficas do Rio Jacaré-Guaçu, com áreas de 1867 e 3519 km2. A adoção da metodologia proposta permite calcular uma vazão de referência sustentável, possibilitando prever a variação da vazão de base nos períodos de recessão, por estar definida em função de precipitações passadas. Portanto, tal vazão seria mais condizente com as observadas no meio ambiente, proporcionando um adequado funcionamento do ecossistema, garantindo assim a sua preservação. Climatic variation may result in insufficient input of water in the water balance in a region, resulting in inconsistencies in the water rights permits. Brazilian water allocation system uses the flow duration curves (Q7,10, Q90, Q95) to establish the maximum allowable discharge. However, during droughts such reference discharges may not reach the water rights permits, requiring groundwater extraction to compensate this deficiency in surface water bodies. Hence, the water right permits must be integral, considering the base flow variation due to the groundwater extraction. The aim of this study is to determine the integrated water availability (surface and groundwater), using an empirical linear model, proposed as a function of the average rainfall of previous periods related to the aquifer regulation time. Correlation and spectral techniques were employed for time-series analysis of precipitation (P) and discharge (Q) in the Ribeirão da Onça watershed, to determine response times of Q as a function of P. The proposed methodology was developed for precipitation and discharge observed from 2003 to 2014 in a watershed with an area of 65 km2. The obtained results indicate that the aquifer stores the rainfall water with regulation times of approximately 60 days for the subsurface flow, ans approximately 2 years for the base flow. The methodology was also tested for two sub-basins of the Jacaré-Guaçú River watershed, with areas of 1867 and 3519 km2.The proposed methodology allows the estimation of a sustainable reference discharge making it possible to predict the base flow variation during recession periods, since it is defined as a function of past rainfall. Therefore, this discharge is more consistent with the values observed in the environment, allowing a proper functioning of the ecosystem, thereby ensuring their preservation.

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Moreira-Paredes, Ramiro. "Nontraditional windows in spectral analysis." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1993. http://handle.dtic.mil/100.2/ADA271336.

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Jamieson, Gary. "Spectral analysis of pulmonary sounds." Thesis, University of Liverpool, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.240595.

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Dissertations / Theses on the topic 'Spectral and temporal analysis'

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