Orientador: Prof. Dr. Ricardo Suyama / Dissertação (mestrado) - Universidade Federal do ABC, Programa de Pós-Graduação em Engenharia da Informação, 2015. / No processo de digitalização de documentos impressos ou manuscritos que apresentam informação em ambos os lados da folha (frente e verso), é comum encontrar uma distorção na imagem digitalizada conhecida como Efeito Show-Through, na qual a imagem digitalizada de um dos lados do documento sofre a interferência da imagem presente no outro lado da folha. O problema de remoção dessa interferência pode ser visto como uma instância do problema geral de Separação Cega de Fontes (BSS ¿ Blind Source Separation), para o qual diferentes técnicas foram propostas, baseadas nas características das fontes e no processo de mistura. No presente trabalho avaliamos diferentes técnicas para a solução do problema de Show-through que utilizam os conceitos relacionados ao problema de Separação Cega de Fontes, buscando identificar vantagens e desvantagens dos diferentes métodos. As técnicas avaliadas, baseadas em três diferentes abordagens em termos do critério de adaptação dos parâmetros, foram testadas com diferentes tipos de documentos (textos antigos ,manuscritos,jornal,etc) digitalizados, considerando misturas sintéticas e misturas reais, obtidas com a digitalização de documentos impressos. Os resultados obtidos revelam pontos fortes e fracos das técnicas avaliadas, e poderão servir como referência para o desenvolvimento de novas técnicas para a correção do efeito Show-Through. / In the digitalization process of printed documents or manuscripts that contain information on both through sides of the paper (front and back), it is common to observe the so-called Show-Thorugh Effet, in which the image in the back of the document interferes in the digitized image of the front side. Removing this kind of interference can be seen as an instance of the general Blind Source Separation Problem (BSS), for which several different techniques have been proposed in the literature, considering specific characteristics of the sources and of the mixing process. The objective of the present work is to evaluate different methods for the mitigation of the Show-Through effect, based in concepts related to the BSS problem. The evaluated tools, based on three different approaches for parameter adaptation, were tested with different kinds of documents (old texts, manuscripts, newspaper), considering synthetic and real mixtures. The results reveal strong and weak points of the studied methods, which can serve as a valuable reference in the development of new techniques for the Show-Through effect mitigation.

Orientadores: João Marcos Travassos Romano, Romis Ribeiro de Faissol Attux / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-08-12T15:14:54Z (GMT). No. of bitstreams: 1 Dias_TiagoMacedo_M.pdf: 3219855 bytes, checksum: 5572e53d65cb457f420e78b3150dd6ee (MD5) Previous issue date: 2008 / Resumo: Esta dissertação se propõe a estudar um novo método para separação cega de fontes baseado no modelo Post-Nonlinear, que une uma ferramenta de busca global baseada em computação bioinspirada a uma etapa de busca local conduzida pelo algoritmo FastICA. A idéia subjacente à proposta é procurar obter soluções precisas e eficientes usando de maneira parcimoniosa os recursos computacionais disponíveis. A nova proposta foi testada em diferentes cenários, e, em todos os casos, estabeleceram-se comparações com uma abordagem alternativa, cujo passo de otimização não inclui o estágio de busca local (ou "memética"). Os resultados obtidos por meio de simulações indicam que um bom compromisso entre desempenho e custo computacional foi, de fato, atingido. / Resumo: Esta dissertação se propõe a estudar um novo método para separação cega de fontes baseado no modelo Post-Nonlinear, que une uma ferramenta de busca global baseada em computação bioinspirada a uma etapa de busca local conduzida pelo algoritmo FastICA. A idéia subjacente à proposta é procurar obter soluções precisas e eficientes usando de maneira parcimoniosa os recursos computacionais disponíveis. A nova proposta foi testada em diferentes cenários, e, em todos os casos, estabeleceram-se comparações com uma abordagem alternativa, cujo passo de otimização não inclui o estágio de busca local (ou "memética"). Os resultados obtidos por meio de simulações indicam que um bom compromisso entre desempenho e custo computacional foi, de fato, atingido. / Abstract: This work deals with a new method for source separation of Post-Nonlinear mixtures that brings together an evolutionary-based global search and a local search step based on the FastICA algorithm. The rationale of the proposal is to attempt to obtain efficient and precise solutions using with parsimony the available computational resources. The new proposal was tested in different scenarios and, in all cases, we attempted to establish grounds for comparison with an alternative approach whose optimization step does not include the local (memetic) search stage. Simulation results indicate that a good tradeoff between performance and computational cost was indeed reached. / Abstract: This work deals with a new method for source separation of Post-Nonlinear mixtures that brings together an evolutionary-based global search and a local search step based on the FastICA algorithm. The rationale of the proposal is to attempt to obtain efficient and precise solutions using with parsimony the available computational resources. The new proposal was tested in different scenarios and, in all cases, we attempted to establish grounds for comparison with an alternative approach whose optimization step does not include the local (memetic) search stage. Simulation results indicate that a good tradeoff between performance and computational cost was indeed reached. / Mestrado / Telecomunicações e Telemática / Mestre em Engenharia Elétrica

Analysis of the field of view from commercial vehicles is very important issue. Because driver’s field of view is main part of active safety. When some traffic accident happens, it must be investigated. The question is, was the driver able to see that object? It’s very different and important if driver didn’t see that object or couldn’t see it. In the thesis are described norms which contains information about driver’s position on driving seat and position his eyes, information about differences between binocular and ambinocular field of view. In the thesis are regulations about rearview and rearview mirrors. The thesis contains elements of vehicle equipment for improvement field of view. The thesis is about possibilities, how measure the field of view from commercial vehicles. The thesis contains few methods for measurements driver’s field of view and theirs results. Objective of the thesis is to take experiences from measured tests and use them for invention and description own method of measuring driver’s field of view from commercial vehicles, which leads to improvement. Then use the method for measurements and comparations few commercial vehicles. Which are dimensionally more bigger and have bigger blind spots than personal vehicles.

La perte de la vision affecte considérablement la capacité de se déplacer dans l’environnement. Les personnes aveugles utilisent aujourd’hui des aides à la mobilité comme la canne blanche et le chien guide. Cependant, ces aides ne donnent pas assez d’information sur l’environnement, et des accidents peuvent parfois survenir, notamment avec des obstacles en hauteur, non détectés par la canne blanche. Les systèmes de substitution sensorielle permettent d’apporter l’information visuelle via une autre modalité intacte comme le toucher. Il en existe principalement deux types, des systèmes de guidages, comme le EyeCane qui donne une information de distance en un point, et des systèmes visuels comme le Tongue Display Unit, basé sur le contraste qui transforme le signal d’une caméra en stimulation électro-tactile sur la langue. Le but de l’étude était de comparer ces deux appareils dans un même couloir à obstacle à taille réelle (21m x 2,4m). Des aveugles précoces et tardifs, et des contrôles voyants aux yeux bandés devaient traverser le couloir tout en détectant, identifiant et évitant les obstacles (cube, porte, sol, poteau) rencontrés. Les résultats ont montré que tous les participants ont été capables de naviguer avec les deux appareils. De plus, avec le EyeCane, les participants aveugles ont significativement mieux évité les obstacles après détection que les voyants, et que les aveugles précoces étaient significativement plus rapides pour traverser le couloir que les deux autres groupes. Cependant, la comparaison entre les deux appareils a révélé que les aveugles tardifs ont détecté significativement plus d’obstacles avec le TDU qu’avec le EyeCane sans pour autant améliorer les performances de navigation. De plus, la quantité d’information sur l’environnement fournie par le TDU semble ralentir et fatiguer les participants après une longue période d’utilisation. On peut alors suggérer que seules les informations de l’environnement immédiat données par le EyeCane sont nécessaires et suffisantes à la navigation. Cette étude permet de mieux guider la conception de futurs appareils destinés à améliorer l’indépendance de navigation chez les personnes aveugles. / Vision loss affects the ability to move around the environment. People who are blind today use mobility aids such as the long cane and guide dog. However, these aids do not provide enough information about the environment, and accidents can sometimes occur, especially with high obstacles not detected by the white cane. Sensory substitution systems allow visual information to be provided via another intact modality such as touch. There are mainly two types: guidance systems, like the EyeCane, that give distance information at a point, and visual systems, like the Tongue Display Unit, based on contrast which transforms the signal from a camera into electrotactile stimulation on the tongue. The aim of the study was to compare these two devices in the same full-size obstacle course (21m x 2.4m). Early and late blind, and blindfolded sighted controls had to cross the hallway while detecting, identifying and avoiding encountered obstacles (cube, door, floor, pole). It was found that all participants were able to navigate with both devices. Furthermore, with the EyeCane, the blind participants were significantly better to avoid obstacles after detection than the sighted, and the early blind were significantly faster to cross the corridor than the other two groups. However, the comparison between the two devices revealed that participants detected significantly more obstacles with the TDU than with the EyeCane without improving navigation performance. In addition, the amount of environmental information provided by the TDU appears to slow down and tire participants after a long period of use. We can then suggest that only the information of the immediate environment given by the EyeCane is necessary and sufficient for navigation. This study helps to guide the design of future devices to improve navigation independence in blind people.

Für blinde und seheingeschränkte Menschen ist die Ausübung des Bewegens im Wasser und das Schwimmen an die Bereitstellung von Hilfsmitteln und -systemen gebunden. Im Para Schwimmen sind dafür die technischen Voraussetzungen zu erschließen, die ein sicheres Bewegen im Wasser autonom und unabhängig von einer dritten Person als Tapper ermöglichen. In der vorliegenden Arbeit werden Konzeption, Entwicklung, Evaluation und Praxistransfer eines induktiven persönlichen Abstandswarnsystems (IPA) zur Anzeige der bevorstehenden Beckenwand bzw. des Schwimmbahnendes präsentiert. Das System basiert auf dem elektromagnetischen Sender-Empfänger-Prinzip. Der stationäre Sender wird an der Beckenwand positioniert und erzeugt im aktivierten Zustand ein Magnetfeld. Der blinde bzw. seheingeschränkte Schwimmer trägt zum Signalempfang am vorderen Schläfenbein eine mobile Empfängereinheit mit integriertem Magnetfeldsensor und miniaturisiertem Vibrationsmotor. Sobald sich ein:e Schwimmer:in in den Empfängerbereich hineinbewegt, erhält sie:er ein taktiles Signal in Form der Vibration mit einer Frequenz von 14.000 Hz über die Dauer von 2 s. Die Labor- und Feldstudien zeigen, dass die Schwimmer das Vibrationssignal des IPA-Systems mit einer Wahrscheinlichkeit von über 99,8 % im Zuge der Wendeneinleitung wahrnehmen. Im Folgenden zeigte eine Evaluationsstudie mit Para Leistungsschwimmern, dass es mit Hilfe des IPA-Systems möglich ist, Wenden in jeder Schwimmart und Belastungsintensität autonom und damit ohne eine dritte Person durchzuführen. Zudem konnte in einer zwanzigwöchigen Interventionsstudie im Training eines Para Leistungsschwimmers durch die Anwendung des IPA-Systems als eine Verbesserung der Wendenzeiten nachgewiesen werden. Weiterer Forschungsbedarf wird in der Untersuchung der Lageabhängigkeit der mobilen Empfängereinheit sowie in der Untersuchung von Individualisierungsstrategien beim Auslösen des taktilen Signals in Abhängigkeit von der Wandentfernung gesehen. Zudem sind im Anwendungsbereich des IPA-Systems weitere Zielgruppen des Para Schwimmens zu erschließen.:Inhaltsverzeichnis Tabellenverzeichnis VII Abbildungsverzeichnis VIII Abkürzungsverzeichnis XI 1 Aufbau der Arbeit und Forschungsstrategie 1 1.1 Forschungsverbund 1 1.2 Projektphasen 3 1.3 Datenerhebung und -auswertung 5 2 Einleitung und Problemstellung 6 3 Initialisierungsphase 7 3.1 Zielgruppen 9 3.2 Theoretische Grundlagen 10 3.2.1 Sehbeeinträchtigung und Blindheit 10 3.2.2 Para Schwimmen 13 3.2.3 Schwimmwende 19 3.3 Stand der Gerätetechnik 25 3.3.1 Stationäre Systeme 25 3.3.2 Mobile Systeme 28 3.3.3 Gesamtübersicht 32 4 Konzeptphase 35 4.1 Expertenbefragung 36 4.2 Hauptanforderungen 39 4.3 Konzeptfragen 40 4.4 Signalübertragung 41 4.4.1 Signalart 44 4.4.2 Empfängerposition grob (Körperregion) 45 4.4.3 Studie 1a: Empfängerposition fein (Kopfregion) 48 4.4.4 Studie 1b: Signalintensität 52 4.4.5 Signaltaktung 57 4.5 Konzeptentwurf 59 5 Realisierungsphase 60 5.1 Prototypsystem und Komponenten 61 5.2 Prototypfunktionsprinzip 62 5.3 Realisierungsstand 63 6 Evaluierungsphase 63 6.1.1 Studie 2: Zuverlässigkeit des IPA-Systems Testumgebung und -ablauf 65 6.1.2 Fragestellungen 67 6.1.3 Ergebnisse 68 6.1.4 Diskussion und Fazit 69 6.2 Studie 3a: 1D- Magnedfeldsensorik 73 6.2.1 Simulation der Schwimmlage 75 6.2.2 Simulation der Anschwimmposition 77 6.2.3 Simulation der Höhendifferenz 80 6.2.4 Diskussion und Fazit 82 6.3 Studie 3b: Mehrdimensionale Sensorik 84 6.3.1 2D-Magnetfeldsensorik 85 6.3.2 3D-Magentfeldsensorik 90 6.3.3 Diskussion und Fazit 93 6.4 Studie 4a: Einfluss der Belastungsintensität auf die taktile Wahrnehmung 96 6.4.1 Fragestellungen 96 6.4.2 Testumgebung und -ablauf 97 6.4.3 Ergebnisse 100 6.5 Studie 4b: Wahrnehmung des Vibrationssignals einer S13 Schwimmerin 103 6.5.1 Fragestellungen 103 6.5.2 Testumgebung und -ablauf 104 6.5.3 Ergebnisse 105 6.5.4 Diskussion und Fazit 106 7 Praxistransferphase 111 7.1 Para Trainingsgruppe 111 7.2 Studie 5: S11-Schwimmer mit zwanzigwöchiger Trainingsintervention 113 7.2.1 Fragestellungen 113 7.2.2 Testumgebung und –ablauf 113 7.2.3 Ergebnisse 116 7.2.4 Diskussion und Fazit 119 7.3 Internationale Deutsche Meisterschaften der Behinderten 2017 124 8 Zusammenfassung 125 9 Ausblick 127 10 Literaturverzeichnis 130 Anhang 142 / For blind and visually impaired people the practice of moving in water and swimming is tied to the provision of an assistive devices and systems. In para-swimming, the technical prerequisites must be developed to enable safe movement in the water autonomously and independently of a third person as a taper. The present work presents the conception, development, evaluation and practical transfer of an inductive personal distance alert (IPA) system for indicating the impending pool wall or the end of the swimming lane in the pool. The system is based on the electromagnetic transmitter-receiver principle. The stationary transmitter is positioned on the pool wall and generates a magnetic field when activated. The blind or visually impaired swimmer wears a mobile receiver unit with an integrated magnetic field sensor and miniaturized vibration motor on the front temporal bone for signal reception. As soon as the swimmer moves into the receiver area, he receives a tactile vibration signal with a frequency of 14 000 Hz over a period of 2 s. The laboratory and field studies document that swimmers perceive the vibration signal from the IPA system with a probability of over 99.8 % in the course of turn initiation. Furthermore, an evaluation study with para competitive swimmers showed that with the help of the IPA system it is possible to perform turns autonomously in any swimming mode and load intensity and thus without a third person. In addition, a twenty-week intervention study in the training of a para competitive swimmer using the IPA system showed an assistance in the improvement in turn times. Further research is needed to investigate the positional dependence of the mobile receiver unit and the individualization strategies for triggering the tactile signal as a function of the wall distance. In addition, further target groups of para-swimming are to be integrated in the application of the IPA system.:Inhaltsverzeichnis Tabellenverzeichnis VII Abbildungsverzeichnis VIII Abkürzungsverzeichnis XI 1 Aufbau der Arbeit und Forschungsstrategie 1 1.1 Forschungsverbund 1 1.2 Projektphasen 3 1.3 Datenerhebung und -auswertung 5 2 Einleitung und Problemstellung 6 3 Initialisierungsphase 7 3.1 Zielgruppen 9 3.2 Theoretische Grundlagen 10 3.2.1 Sehbeeinträchtigung und Blindheit 10 3.2.2 Para Schwimmen 13 3.2.3 Schwimmwende 19 3.3 Stand der Gerätetechnik 25 3.3.1 Stationäre Systeme 25 3.3.2 Mobile Systeme 28 3.3.3 Gesamtübersicht 32 4 Konzeptphase 35 4.1 Expertenbefragung 36 4.2 Hauptanforderungen 39 4.3 Konzeptfragen 40 4.4 Signalübertragung 41 4.4.1 Signalart 44 4.4.2 Empfängerposition grob (Körperregion) 45 4.4.3 Studie 1a: Empfängerposition fein (Kopfregion) 48 4.4.4 Studie 1b: Signalintensität 52 4.4.5 Signaltaktung 57 4.5 Konzeptentwurf 59 5 Realisierungsphase 60 5.1 Prototypsystem und Komponenten 61 5.2 Prototypfunktionsprinzip 62 5.3 Realisierungsstand 63 6 Evaluierungsphase 63 6.1.1 Studie 2: Zuverlässigkeit des IPA-Systems Testumgebung und -ablauf 65 6.1.2 Fragestellungen 67 6.1.3 Ergebnisse 68 6.1.4 Diskussion und Fazit 69 6.2 Studie 3a: 1D- Magnedfeldsensorik 73 6.2.1 Simulation der Schwimmlage 75 6.2.2 Simulation der Anschwimmposition 77 6.2.3 Simulation der Höhendifferenz 80 6.2.4 Diskussion und Fazit 82 6.3 Studie 3b: Mehrdimensionale Sensorik 84 6.3.1 2D-Magnetfeldsensorik 85 6.3.2 3D-Magentfeldsensorik 90 6.3.3 Diskussion und Fazit 93 6.4 Studie 4a: Einfluss der Belastungsintensität auf die taktile Wahrnehmung 96 6.4.1 Fragestellungen 96 6.4.2 Testumgebung und -ablauf 97 6.4.3 Ergebnisse 100 6.5 Studie 4b: Wahrnehmung des Vibrationssignals einer S13 Schwimmerin 103 6.5.1 Fragestellungen 103 6.5.2 Testumgebung und -ablauf 104 6.5.3 Ergebnisse 105 6.5.4 Diskussion und Fazit 106 7 Praxistransferphase 111 7.1 Para Trainingsgruppe 111 7.2 Studie 5: S11-Schwimmer mit zwanzigwöchiger Trainingsintervention 113 7.2.1 Fragestellungen 113 7.2.2 Testumgebung und –ablauf 113 7.2.3 Ergebnisse 116 7.2.4 Diskussion und Fazit 119 7.3 Internationale Deutsche Meisterschaften der Behinderten 2017 124 8 Zusammenfassung 125 9 Ausblick 127 10 Literaturverzeichnis 130 Anhang 142

This research focuses on the grief and emotional reactions, especially frustration, of adventitiously visually impaired adults following loss of sight. The traditional grief-following loss theory with the assumption of a time-limited linear grief process, accompanied by diminishing emotions and culminating with acceptance and adjustment has been challenged. Chronic grief assumes a recurrent and continuous grief process, accompanied by increased emotions associated with continual losses related to a chronic loss, such as visual impairment. The question of whether there is a relation between length of time of adventitious visual impairment and the healing affect of time on grief and frustrations has been examined by quantitative and qualitative investigations. The answer to the question of whether time changes and heals everything is not necessarily the case. As always there are more questions than answers, and this research provides further insight into the real world of adventitious visual impairment. / Psychology / M.A. (Psychology)

Time-Interleaved Analog to Digital Converters (TI ADC) consist of several individual sub-converters operating at a lower sampling rate, working in parallel, and in a circular loop. Thereby, they are increasing the sampling rate without compromising on the resolution during conversion, at high sampling rates. The latter is the main requirement in the area of radio frequency sampling. However, they suffer from mismatches caused by the different characteristics in each sub-converter and the TI structure. The output of the TI ADC under consideration contains a lot of harmonics and spurious tones due to the non-linearities mismatch between the sub-converters. Therefore, previously extensive frequency planning was performed to avoid the input signal from coinciding with these harmonic bins. More importance has been given to digital calibration in recent years where algorithms are developed and implemented outside ADC in a Digital signal processor (DSP), whereas the compensation is done in real time. In this work, we model the distortions and the harmonics present in the TI ADC output to get a clear understanding of the TI ADC. A post-correction block is developed for the cancellation of the characterized harmonics. The suggested method is tested on the TI ADCs working at radio frequencies, but is valid also for other types of ADCs, such as pipeline ADCs and sigma-delta ADCs.

ITC/USA 2011 Conference Proceedings / The Forty-Seventh Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2011 / Bally's Las Vegas, Las Vegas, Nevada / Multi-H Continuous Phase Modulation is a highly bandwidth efficient constant amplitude modulation scheme. Because of these qualities it was selected as the Advanced Range Telemetry (ARTM) tier II waveform. In the past, two demodulation techniques have widely been proposed, coherent detection and non-coherent detection. This paper presents a receiver design that implements a hybrid, partially coherent detection scheme that takes advantage of the positive aspects of both coherent and non-coherent detection. Because complete phase recovery is not required, the hybrid receiver performs better in environments with fast fading, strong phase noise, and multi path when compared to the traditional coherent receiver. The hybrid receiver can also acquire and reacquire signals much faster than conventional coherent receivers. The hybrid receiver design implements a partial carrier detection scheme that utilizes phase information that performs much better in AWGN environments than typical non-coherent receivers. Simulation results show that the hybrid receiver has low implementation loss compared to the optimal Maximum Likelihood Sequence Estimation (MLSE) receiver.

published_or_final_version / Social Work / Master / Master of Social Work

published_or_final_version / Urban Planning / Master / Master of Science in Urban Planning