Tesis sobre el tema "Noisy environments"
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Aschauer, Hans. "Quantum communication in noisy environments". Diss., lmu, 2005. http://nbn-resolving.de/urn:nbn:de:bvb:19-35882.
Texto completoJaisimha, M. Y. "Compound document retrieval in noisy environments /". Thesis, Connect to this title online; UW restricted, 1996. http://hdl.handle.net/1773/6007.
Texto completoParikh, Devangi Nikunj. "Improving the quality of speech in noisy environments". Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/45889.
Texto completoNayfeh, Taysir H. "Multi-signal processing for voice recognition in noisy environments". Thesis, This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-10222009-125021/.
Texto completoChen, Aimin. "Speech recognition and enhancement in noisy cellular mobile environments". Thesis, Brunel University, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.251198.
Texto completoLaidler, Jonathan. "Modelling of glimpses for speech recognition in noisy environments". Thesis, University of Sheffield, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.575364.
Texto completoJimenez, Blazquez Lara. "Mathematical Methods for Maritime Signal Curation in Noisy Environments". Thesis, Mälardalens högskola, Akademin för utbildning, kultur och kommunikation, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-43653.
Texto completoMahfoudia, Osama. "DVB-T based bistatic passive radars in noisy environments". Doctoral thesis, Universite Libre de Bruxelles, 2017. https://dipot.ulb.ac.be/dspace/bitstream/2013/258499/5/contratOM.pdf.
Texto completoDoctorat en Sciences de l'ingénieur et technologie
info:eu-repo/semantics/nonPublished
Gajic, Bojana. "Feature Extraction for Automatic Speech Recognition in Noisy Acoustic Environments". Doctoral thesis, Norwegian University of Science and Technology, Faculty of Information Technology, Mathematics and Electrical Engineering, 2002. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-441.
Texto completoThis thesis presents a study of alternative speech feature extraction methods aimed at increasing robustness of automatic speech recognition (ASR) against additive background noise.
Spectral peak positions of speech signals remain practically unchanged in presence of additive background noise. Thus, it was expected that emphasizing spectral peak positions in speech feature extraction would result in improved noise robustness of ASR systems. If frequency subbands are properly chosen, dominant subband frequencies can serve as reasonable estimates of spectral peak positions. Thus, different methods for incorporating dominant subband frequencies into speech feature vectors were investigated in this study.
To begin with, two earlier proposed feature extraction methods that utilize dominant subband frequency information were examined. The first one uses zero-crossing statistics of the subband signals to estimate dominant subband frequencies, while the second one uses subband spectral centroids. The methods were compared with the standard MFCC feature extraction method on two different recognition tasks in various background conditions. The first method was shown to improve ASR performance on both recognition tasks at sufficiently high noise levels. The improvement was, however, smaller on the more complex recognition task. The second method, on the other hand, led to some reduction in ASR performance in all testing conditions.
Next, a new method for incorporating subband spectral centroids into speech feature vectors was proposed, and was shown to be considerably more robust than the standard MFCC method on both ASR tasks. The main difference between the proposed method and the zero-crossing based method is in the way they utilize dominant subband frequency information. It was shown that the performance improvement due to the use of dominant subband frequency information was considerably larger for the proposed method than for the ZCPA method, especially on the more complex recognition task. Finally, the computational complexity of the proposed method is two orders of magnitude lower than that of the zero-crossing based method, and of the same order of magnitude as the standard MFCC method.
Wu, Mingyang. "Pitch tracking and speech enhancement in noisy and reverberant environments". Columbus, Ohio : Ohio State University, 2003. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1064341479.
Texto completoTitle from first page of PDF file. Document formatted into pages; contains xvi, 149 p.; also includes graphics. Includes abstract and vita. Advisor: DeLiang Wang, Dept. of Computer and Information Science. Includes bibliographical references (p. 136-149).
Bettadapura, Raghuprasad Shivatejas. "Echo Delay Estimation to Aid Source Localization in Noisy Environments". Thesis, Virginia Tech, 2014. http://hdl.handle.net/10919/50517.
Texto completoMaster of Science
Wiltgen, Timothy Edward. "Adaptive Beamforming using ICA for Target Identification in Noisy Environments". Thesis, Virginia Tech, 2007. http://hdl.handle.net/10919/33118.
Texto completoMaster of Science
Rådsten-Ekman, Maria. "MAY NOISY SOUND ENVIRONMENTS BE IMPROVED BY ADDING PLEASANT WATER SOUNDS?" Thesis, Stockholms universitet, Psykologiska institutionen, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-43834.
Texto completoMunlin, Joyce C. "The effect of three variables on synthetic speech intelligibility in noisy environments". Thesis, Monterey, California. Naval Postgraduate School, 1990. http://hdl.handle.net/10945/30702.
Texto completoMilitary Command and Control (C2) requires easy access to information needed for the commander's situation assessment and direction of troops. Providing this information via synthetic speech is a viable alternative, but additional information is required before speech systems can be implemented for C2 functions. An experiment was conducted to study several factors which may affect the intelligibility of synthetic speech. The factors examined were: (1) speech rate; (2) synthetic speech messages presented at lower, the same, and higher frequencies than background noise frequency; (3) voice richness; and (4) interactions between speech rate, voice fundamental frequency, and voice richness. Response latency and recognition accuracy were measured. Results clearly indicate that increasing speech rate leads to an increase latency and a decrease in recognition accuracy, at least for the novice user. No effect of voice fundamental frequency or richness was demonstrated.
Chuang, Chern. "Spectroscopy, relaxation, and transport of molecular excitons in noisy and disordered environments". Thesis, Massachusetts Institute of Technology, 2018. http://hdl.handle.net/1721.1/115803.
Texto completoCataloged from PDF version of thesis.
Includes bibliographical references (pages 139-150).
In this thesis contribution we theoretically investigate the spectroscopy, relaxation, and transport properties of Frenkel excitons in molecular aggregates, with extensive comparison to or prediction of experimental observables. Particular emphasis is devoted to the effects of thermal noise, static disorder, and system dimensionality. Our key contributions are summarized as the following. We study the spectroscopic signatures of excitonic molecular aggregates of dimensionality larger than unity as functions of temperature and disorder strength. These findings are applied to the determination of essential system characteristics and quantitatively explain the spectroscopic traits seen in experiments where either the temperature or disorder strength is altered. A classification scheme generalized from Kasha's seminal work on J- and H-aggregates is proposed that is compatible with experimental observations previously unexplained. We recognize the importance of long-wavelength approximations in understanding the density of states in two-dimensional excitonic aggregates. And for tubular aggregates this leads to a simple expression for the energy gap between the parallel- and the perpendicular-polarized peaks useful in inferring key system parameters. This long-wavelength approach is then extended to the analysis of 2D excitonic molecular aggregates in general. A universal scaling relation concerning the steady-state diffusive transport of excitons in molecular tubes is predicted and analyzed, where the key order parameter is identified as the ratio between the localization length of the exciton wavefunctions and the tube circumference. A unified theoretical framework is proposed to explain the relaxation of hot excitons generated in emissive conjugated polymers across three orders of magnitude in timescale, with quantitative agreements with experiments.
by Chern Chuang.
Ph. D.
健紘, 大田 y Kenko Ota. "Studies in signal processing for robust speech recognition in noisy and reverberant environments". Thesis, https://doors.doshisha.ac.jp/opac/opac_link/bibid/BB10268908/?lang=0, 2008. https://doors.doshisha.ac.jp/opac/opac_link/bibid/BB10268908/?lang=0.
Texto completoNovoa, Ilic José Eduardo. "Robust speech recognition in noisy and reverberant environments using deep neural network-based systems". Tesis, Universidad de Chile, 2018. http://repositorio.uchile.cl/handle/2250/168062.
Texto completoIn this thesis an uncertainty weighting scheme for deep neural network-hidden Markov model (DNN-HMM) based automatic speech recognition (ASR) is proposed to increase discriminability in the decoding process. To this end, the DNN pseudo-log-likelihoods are weighted according to the uncertainty variance assigned to the acoustic observation. The results presented here suggest that substantial reduction in word error rate (WER) is achieved with clean training. Moreover, modelling the uncertainty propagation through the DNN is not required and no approximations for non linear activation functions are made. The presented method can be applied to any network topology that delivers log likelihood-like scores. It can be combined with any noise removal technique and adds a minimal computational cost. This technique was exhaustively evaluated and combined with uncertainty-propagation-based schemes for computing the pseudo-log-likelihoods and uncertainty variance at the DNN output. Two proposed methods optimized the parameters of the weighting function by leveraging the grid search either on a development database representing the given task or on each utterance based on discrimination metrics. Experiments with Aurora-4 task showed that, with clean training, the proposed weighting scheme can reduce WER by a maximum of 21% compared with a baseline system with spectral subtraction and uncertainty propagation using the unscented transform. Additionally, it is proposed to replace the classical black box integration of automatic speech recognition technology in human-robot interaction (HRI) applications with the incorporation of the HRI environment representation and modeling, and the robot and user states and contexts. Accordingly, this thesis focuses on the environment representation and modeling by training a DNN-HMM based automatic speech recognition engine combining clean utterances with the acoustic channel responses and noise that were obtained from an HRI testbed built with a PR2 mobile manipulation robot. This method avoids recording a training database in all the possible acoustic environments given an HRI scenario. In the generated testbed, the resulting ASR engine provided a WER that is at least 26% and 38% lower than publicly available speech recognition application programming interfaces (APIs) with the loudspeaker and human speakers testing databases, respectively, with a limited amount of training data. This thesis demonstrates that even state-of-the-art DNN-HMM based speech recognizers can benefit by combining systems for which the acoustic models have been trained using different feature sets. In this context, the complementarity of DNN-HMM based ASR systems trained with the same data set but with different signal representations is discussed. DNN fusion methods based on flat-weight combination, the minimization of mutual information and the maximization of discrimination metrics were proposed and tested. Schemes that consider the combination of ASR systems with lattice combination and minimum Bayes risk decoding were also evaluated and combined with DNN fusion techniques. The experimental results were obtained using a publicly-available naturally-recorded highly reverberant speech data. Significant improvements in WER were observed by combining DNN-HMM based ASR systems with different feature sets, obtaining relative improvements of 10% with two classifiers and 18% with four classifiers, without any tuning or a priori information of the ASR accuracy.
Goeckel, Tom [Verfasser], Gerhard [Akademischer Betreuer] Lakemeyer y Hermann [Akademischer Betreuer] Wagner. "Efficient Binaural Sound Localization in Noisy and Reverberant Environments / Tom Goeckel ; Gerhard Lakemeyer, Hermann Wagner". Aachen : Universitätsbibliothek der RWTH Aachen, 2015. http://d-nb.info/1130402738/34.
Texto completoKuhr, Mark Gregory Hamilton John A. "An adaptive jam-resistant cross-layer protocol for mobile ad-hoc networks In noisy environments". Auburn, Ala., 2009. http://hdl.handle.net/10415/1611.
Texto completoRoberts, David James. "Applications of Artificial Neural Networks to Synthetic Aperture Radar for Feature Extraction in Noisy Environments". DigitalCommons@CalPoly, 2013. https://digitalcommons.calpoly.edu/theses/996.
Texto completoGstach, Dieter. "Small sample performance of two approaches to technical efficiency estimation in noisy multiple output environments". Inst. für Volkswirtschaftstheorie und -politik, WU Vienna University of Economics and Business, 1998. http://epub.wu.ac.at/1190/1/document.pdf.
Texto completoSeries: Department of Economics Working Paper Series
NAKAMURA, Satoshi, Kazuya TAKEDA y Masakiyo FUJIMOTO. "CENSREC-3: An Evaluation Framework for Japanese Speech Recognition in Real Car-Driving Environments". Institute of Electronics, Information and Communication Engineers, 2006. http://hdl.handle.net/2237/15050.
Texto completoBraun, Sebastian [Verfasser], Emanuel [Gutachter] Habets y Patrick [Gutachter] Naylor. "Speech dereverberation in noisy environments using time-frequency domain signal models / Sebastian Braun ; Gutachter: Emanuel Habets, Patrick Naylor". Erlangen : Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 2018. http://d-nb.info/1155590597/34.
Texto completoHeidrich-Meisner, Verena [Verfasser], Gregor [Gutachter] Schöner y Christian [Gutachter] Igel. "Evolutionary direct policy search in noisy environments / Verena Heidrich-Meisner ; Gutachter: Gregor Schöner, Christian Igel ; Fakultät für Physik und Astronomie". Bochum : Ruhr-Universität Bochum, 2011. http://d-nb.info/1217845216/34.
Texto completoBoczkowski, Lucas. "Search and broadcast in stochastic environments, a biological perspective". Thesis, Sorbonne Paris Cité, 2018. http://www.theses.fr/2018USPCC044.
Texto completoThis thesis is built around two series of works, each motivated by experiments on ants. We derive and analyse new models,that use computer science concepts and methodology, despite their biological roots and motivation.The first model studied in this thesis takes its inspiration in collaborative transport of food in the P. Longicornis species. Wefind that some key aspects of the process are well described by a graph search problem with noisy advice. The advicecorresponds to characteristic short scent marks laid in front of the load in order to facilitate its navigation. In this thesis, weprovide detailed analysis of the model on trees, which are relevant graph structures from a computer science standpoint. Inparticular our model may be viewed as a noisy extension of binary search to trees. Tight results in expectation and highprobability are derived with matching upper and lower bounds. Interestingly, there is a sharp phase transition phenomenon forthe expected runtime, but not when the algorithms are only required to succeed with high probability.The second model we work with was initially designed to capture information broadcast amongst desert ants. The model usesa stochastic meeting pattern and noise in the interactions, in a way that matches experimental data. Within this theoreticalmodel, we present in this document a strong lower bound on the number of interactions required before information can bespread reliably. Experimentally, we see that the time required for the recruitment process of even few ants increases sharplywith the group size, in accordance with our result. A theoretical consequence of the lower bound is a separation between theuniform noisy PUSH and PULL models of interaction. We also study a close variant of broadcast, without noise this time butunder more strict convergence requirements and show that in this case, the problem can be solved efficiently, even with verylimited exchange of information on each interaction
Chakrabarty, Soumitro [Verfasser], Emanuel [Akademischer Betreuer] Habets y Emanuel [Gutachter] Habets. "Robust Direction-of-Arrival estimation and spatial filtering in noisy and reverberant environments / Soumitro Chakrabarty ; Gutachter: Emanuel Habets ; Betreuer: Emanuel Habets". Erlangen : Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 2020. http://d-nb.info/1211822036/34.
Texto completoAlali, Khaled Ahmed. "Azimuthal Localization and Detection of Vehicular Backup Alarms Under Electronic and Non-Electronic Hearing Protection Devices in Noisy and Quiet Environments". Diss., Virginia Tech, 2011. http://hdl.handle.net/10919/26890.
Texto completoPh. D.
Sidorenko, Juri [Verfasser], Urs [Akademischer Betreuer] Hugentobler, Urs [Gutachter] Hugentobler, Christian [Gutachter] Schindelhauer y Johann [Gutachter] Dambeck. "Self-calibration of time-based localization systems in noisy environments with nonlinear optimization / Juri Sidorenko ; Gutachter: Urs Hugentobler, Christian Schindelhauer, Johann Dambeck ; Betreuer: Urs Hugentobler". München : Universitätsbibliothek der TU München, 2021. http://d-nb.info/1231434600/34.
Texto completoSandström, Rasmus y Jonas Renngård. "En undersökning och jämförelse av två röststyrningsramverk för Android i bullriga miljöer". Thesis, Högskolan Dalarna, Informatik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:du-25579.
Texto completoRöststyrning är idag en teknologi som de flesta människor någon gång stöter på eller använder sig av dagligen. Röststyrningsteknologin kan användas för att tolka vissa kommandon som sedan utför en uppgift baserat på det kommando som uttalas. Enligt tidigare studier uppkommer det problem med precisionen hos de röststyrningsramverk som används i bullriga miljöer. Denna studie har utförts som ett experiment där precisionen hos två stycken röststyrningsramverk för Android har undersökts. Syftet med denna studie var att undersöka precisionen hos dessa ramverk för att bistå med underlag till en organisation som utvecklat en applikation som används av barnmorskor i låg- och medelinkomstländer. Två stycken prototyper utvecklades med hjälp av röststyrningsramverken PocketSphinx och iSpeech. Dessa ramverks precision testades i tre stycken olika miljöer. De miljöer som prototyperna testades i hade ljudnivåerna 25dB, 60dB samt 80dB. Resultatet påvisar att antalet korrekt registrerade kommandon minskar avsevärt beroende på vilken ljudnivå som ramverken testas i. Det ramverk som korrekt registrerade flest röstkommandon var PocketSphinx men även denna hade en stor felmarginal.
Occelli, Florian. "Effet d’une exposition à long-terme à un milieu bruité sur l’audiogramme et les propriétés fonctionnelles des neurones du cortex auditif primaire". Thesis, Université Paris-Saclay (ComUE), 2015. http://www.theses.fr/2015SACLS165.
Texto completoOver the last few years, studies have described alarming effects of exposure to artificial acoustic environments on the functional properties of neurons in the auditory system. The aim of this project was to determine if long-lasting exposure at a sound intensity which is not recognized by the legislation to cause permanent or temporary hearing loss (80 dB SLP 8h/ day) induced, or not, changes in the audiograms and functional properties of neurons in theprimary auditory cortex. Adult female rats (Sprague Dawley) were exposed over 3 to 18 months (depending on the group) to an acoustic environment mimicking daily sound environments surrounding a large part of the population, and whose effects have never been studied on such durations. The originality of this project lies in analyzing the effects at alllevels of the auditory system from peripheral (via ABRs) to central levels (cortical electrophysiology) and also the possible consequences at the behavioral level. A new perceptual learning task has been developed to assess the effects of exposure. During aging, our data showed a decrease in behavioral performance, a gradual impairment of ABRs thresholds as well as an impairment in parameters of the neural responses such as (i) the response latency, (ii) response duration, (iii) the ability to detect silence in a vocalization (iv) or to follow an amplitude modulation, (v) the reproducibility of response to vocalization. The main effect of exposure to a noisy environment is the appearance of a Temporary Threshold Shift (TTS) after 6 to 12 months of exposure (which completely disappears in three weeks). Surprisingly, this long lasting TTS had apparently no e ffect on ABRs thresholds, the evokedcortical activity, or the animal’s discrimination performance. These results encourage us to be quite cautious in generalizing the conclusions to be drawn from exposures to artificial noisyenvironments
Fatoorechi, Mohsen. "Electroencephalogram signal acquisition in unshielded noisy environment". Thesis, University of Sussex, 2015. http://sro.sussex.ac.uk/id/eprint/55034/.
Texto completoAfiomah, Stephen U. "A decision-directed-detection scheme for PCM systems in a noisy environment". Ohio : Ohio University, 1986. http://www.ohiolink.edu/etd/view.cgi?ohiou1183125570.
Texto completoGeorgiadis, Apostolos T. "Adaptive equalisation for impulsive noise environments". Thesis, University of Edinburgh, 2001. http://hdl.handle.net/1842/429.
Texto completoWilson, John Michael. "Robust communication in a time-varying noisy environment". Thesis, Virginia Polytechnic Institute and State University, 1987. http://hdl.handle.net/10919/80062.
Texto completoMaster of Science
Peng, Dandan y 彭丹丹. "Compact environmental noise absorber". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2014. http://hdl.handle.net/10722/209491.
Texto completopublished_or_final_version
Mechanical Engineering
Master
Master of Philosophy
SANTOS, DEBORA ANDREA DE OLIVEIRA. "SPEECH RECOGNITION IN NOISE ENVIRONMENT". PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2001. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=1987@1.
Texto completoEste trabalho apresenta um estudo comparativo de três técnicas de melhoria das taxas de reconhecimento de voz em ambiente adverso, a saber: Normalização da Média Cepestral (CMN), Subtração Espectral e Regressão Linear no Sentido da Máxima Verossimilhança (MLLR), aplicadas isoladamente e em concomitância, duas a duas. Os testes são realizados usando um sistema simples: reconhecimento de palavras isoladas (dígitos de zero a nove, e meia), modo dependente do locutor, modelos ocultos de Markov do tipo contínuo, e vetores de atributos com doze coeficientes cepestrais derivados da análise de predição linear. São adotados três tipos de ruído (gaussiano branco, falatório e de fábrica) em nove razões sinal-ruído diferentes. Os resultados experimentais demonstram que o emprego isolado das técnicas de reconhecimento robusto é, em geral, vantajoso, pois nas diversas razões sinal-ruído para as quais os testes são efetuados, quando as taxas de reconhecimento não sofrem um acréscimo, mantém-se as mesmas obtidas quando não se aplica nenhum método de aumento da robustez. Analisando-se comparativamente as implementações isoladas e simultânea das técnicas, constata-se que a simultânea nem sempre é atraente, dependendo da dupla empregada. Apresentam-se, ainda, os resultados decorrentes do uso de modelos ruidosos, observando-se que, embora sejam inegavelmente melhores, sua utilização é inviável na prática. Das técnicas implementadas, a que representa resultados mais próximos ao emprego de modelos ruidosos é a MLLR, seguida pela CMN, e por último pela Subtração Espectral. Estas últimas, embora percam em desempenho para a primeira, apresentam como vantagem a simplicidade e a generalidade. No que concerne as técnicas usadas concomitantemente, a dupla Subtração Espectral e MLLR é a considerada de melhor performance, pois mostra-se conveniente em relação ao emprego isolado de ambos os métodos, o que nem sempre ocorre com o uso de outras combinações das técnicas individuais.
This work presents a comparative study of three techniques for improving the speech recognition rates in adverse environment, namely: Cepstral Mean Normalization (CMN), Spectral Subtraction and Maximum Likelihood Linear Regression (MLLR). They are implemented in two ways: separately and in pairs. The tests are carried out on a simple system: recognition of isolated words (digits from zero to nine, and the word half), speaker-dependent mode, continuous hidden Markov models, and speech feature vectors with twelve cepstral coefficients derived from linear predictive analysis. Three types of noise are considered (the white one, voice babble and from factory) at nine different signal-to-noise ratios. Experimental result demonstrate that it is worth using separately the techniques of robust recognition. This is because for all signal-to-noise conditions when the recognition accuracy is not improved it is the same one obtained when no method for increasing the robustness is applied. Analyzing comparatively the isolated and simultaneous applications of the techniques, it is verified that the later is not always more attractive than the former one. This depends on the pair of techniques. The use of noisy models is also considered. Although it presents better results, it is not feasible to implement in pratical situations. Among the implemented techniques, MLLR presents closer results to the ones obtaneid with noisy models, followed by CMN, and, at last, by Spectral Subtraction. Although the two later ones are beaten by the first, in terms of recognition accuracy, their advantages are the simplicity and the generality. The use of simultaneous techniques reveals that the pair Spectral Subtraction and MLLR is the one with the best performance because it is superior in comparison with the individual use of both methods. This does not happen with other combination of techniques.
Este trabajo presenta un estudio comparativo de tres técnicas de mejoría de las tasas de reconocimiento de voz en ambiente adverso, a saber: Normalización de la Media Cepextral (CMN), Substracción Espectral y Regresión Lineal en el Sentido de la Máxima Verosimilitud (MLLR), aplicadas separada y conjuntamente, dos a dos. Las pruebas son realizados usando un sistema simple: reconocimiento de palabras aisladas (dígitos de cero al nueve, y media), de modo dependiente del locutor, modelos ocultos de Markov de tipo contínuo, y vectores de atributos con doce coeficientes cepextrales derivados del análisis de predicción lineal. Se adoptan tres tipos de ruido (gausiano blanco, parlatorio y de fábrica) en nueve razones señal- ruido diferentes. Los resultados experimentales demuestran que el empleo aislado de las técnicas de reconocimiento robusto es, en general, ventajoso, pues en las diversas relaciones señal ruido para las cuales las pruebas son efetuadas, cuando la tasa de reconocimiento no aumenta, manteniendo las mismas tasas cuando no se aplica ningún método de aumento de robustez. Analizando comparativamente las implementaciones aisladas y simultáneas de las técnicas, se constata que no siempre la simultánea resulta atractiva, dependiendo de la dupla utilizada. Se presentan además los resultados al utilizar modelos ruidosos, observando que, aunque resultan mejores, su utilización em la práctica resulta inviable. De las técnicas implementadas, la que presenta resultados más próximos al empleo de modelos ruidosos es la MLLR, seguida por la CMN, y por último por la Substracción Espectral. Estas últimas, aunque tienen desempeño peor que la primera, tienen como ventaja la simplicidad y la generalidad. En lo que se refiere a las técnicas usadas concomitantemente, la dupla Substracción Espectral y MLLR es la de mejor performance, pues se muestra conveniente en relación al empleo aislado de ambos métodos, lo que no siempre ocurre con el uso de otras combinaciones de las técnicas individuales.
Renault, Raphael. "Detection of Fast Moving Pulses in a Noisy Environment". Thesis, Virginia Tech, 2000. http://hdl.handle.net/10919/31041.
Texto completo Each element of the proposed architecture is studied separately, and modeled analytically. As a result, a design method is proposed in order to develop an appropriate solution to any system requiring accurate time delay measurements in noisy environments. This general method is then applied to a real system, and the results in terms of detection improvement and rms timing error of the method meet expectations: the signal to noise ratio (SNR) operating point of the system is lowered by 10dB, and correlation proves to generate 2dB less rms timing error than threshold.
Master of Science
Ledoux, Christelle Michelle. "Robust speech filtering in impulsive noise environments". Thesis, Virginia Tech, 1999. http://hdl.handle.net/10919/46325.
Texto completoMaster of Science
Rybing, Peter. "Active Noise Control in Home Environment". Thesis, KTH, Reglerteknik, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-109486.
Texto completoMiksis-Olds, Jennifer L. "Manatee response to environmental noise /". View online ; access limited to URI, 2006. http://0-wwwlib.umi.com.helin.uri.edu/dissertations/dlnow/3225323.
Texto completoLi, Qi. "Advanced morphological filters for processing transient signals in noisy environment". Thesis, University of Liverpool, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.406637.
Texto completoBORGES, FRED BERKOWICZ. "LOW RATE CODECS OPERATING IN NOISY ENVIRONMENT AND IP NETWORKS". PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2005. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=6358@1.
Texto completoEste trabalho examina o impacto da quantização vetorial das LSFs sobre a qualidade de voz em codecs a baixas taxas operando em redes IP e em diversos ambientes ruidosos. São considerados diferentes esquemas de quantização vetorial (QV) multiestágio com busca em árvore envolvendo QV sem memória e QV preditiva chaveada com 2 e 4 classes. A distribuição de perda de quadros em redes IP foi modelada de acordo com o Modelo de Gilbert e a avaliação de desempenho foi realizada tanto em termos das distorções espectrais como da qualidade de voz resultante de codecs a baixas taxas. Ainda neste trabalho, foi avaliada a qualidade da voz codificada após a utilização de uma técnica de supressão de ruído baseada em transformadas wavelets (Wavelet Denoising).
This work investigates the impact of LSF vector quantisation over the voice quality in low rate codecs operating in IP networks. Tree-structured multistage vector quantisation (VQ) schemes involving memoryless VQ and switched-predictive VQ with 2 and 4 classes are considered. The packet loss frame distribution in IP networks was modelled according to the Gilbert Model and the performance was carried out both in terms of spectral distortions and the speech quality at the out put of low rate codecs. In this work, we also evaluated the quality of the coded speech after employing Wavelet Denoising.
Sun, Deqiang. "Landau-Zener transitions in noisy environment and many-body systems". [College Station, Tex. : Texas A&M University, 2009. http://hdl.handle.net/1969.1/ETD-TAMU-2009-05-773.
Texto completoMakhubela, J. K. "Visual simultaneous localization and mapping in a noisy static environment". Thesis, Vaal University of Technology, 2019. http://hdl.handle.net/10352/462.
Texto completoSimultaneous Localization and Mapping (SLAM) has seen tremendous interest amongst the research community in recent years due to its ability to make the robot truly independent in navigation. Visual Simultaneous Localization and Mapping (VSLAM) is when an autonomous mobile robot is embedded with a vision sensor such as monocular, stereo vision, omnidirectional or Red Green Blue Depth (RGBD) camera to localize and map an unknown environment. The purpose of this research is to address the problem of environmental noise, such as light intensity in a static environment, which has been an issue that makes a Visual Simultaneous Localization and Mapping (VSLAM) system to be ineffective. In this study, we have introduced a Light Filtering Algorithm into the Visual Simultaneous Localization and Mapping (VSLAM) method to reduce the amount of noise in order to improve the robustness of the system in a static environment, together with the Extended Kalman Filter (EKF) algorithm for localization and mapping and A* algorithm for navigation. Simulation is utilized to execute experimental performance. Experimental results show a 60% landmark or landfeature detection of the total landmark or landfeature within a simulation environment and a root mean square error (RMSE) of 0.13m, which is minimal when compared with other Simultaneous Localization and Mapping (SLAM) systems from literature. The inclusion of a Light Filtering Algorithm has enabled the Visual Simultaneous Localization and Mapping (VSLAM) system to navigate in an obscure environment.
Huang, Jiehui. "Generation of entanglement and its decay in a noisy environment". HKBU Institutional Repository, 2007. http://repository.hkbu.edu.hk/etd_ra/897.
Texto completoVolchansky, Nadezhda V. "Identifying sleep-disruptive noise factors in healthcare environments". Greensboro, N.C. : University of North Carolina at Greensboro, 2007. http://libres.uncg.edu/edocs/etd/1504Volchansky/umi-uncg-1504.pdf.
Texto completoTitle from PDF t.p. (viewed Feb. 28, 2008). Directed by Kenneth Gruber; submitted to the School of Human Environmental Sciences. Includes bibliographical references (p. 67-70).
Moeller, Michael M. Jr. "Noise environment characterization in military treatment facilities". Thesis, Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/48995.
Texto completoAlberola, Javier. "Predicting variability in environmental noise measurements". Thesis, University of Southampton, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.414693.
Texto completoKrishnan, Venkatesh. "A framework for low bit-rate speech coding in noisy environment". Diss., Available online, Georgia Institute of Technology, 2005, 2005. http://etd.gatech.edu/theses/available/etd-04042005-182043/unrestricted/krishnan%5Fvenkatesh%5F200505%5Fphd.pdf.
Texto completoAnderson, David, Committee Chair ; Barnwell-III, Thomas, Committee Member ; Clements, Mark, Committee Member ; Truong, Kwan, Committee Member ; Basu, Saugata, Committee Member. Vita. Includes bibliographical references.
Myers, M. Parker (Marion Parker). "Improving production testing of RF products in a noisy measurement environment". Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/10942.
Texto completoIncludes bibliographical references (leaf 60).
by M. Parker Myers.
M.S.