La caractérisation du ressenti global du bruit intérieur d’habitacle passe par la définition des conditions conduisant à l’audibilité de ces composantes fréquentielles, émergeant du bruit de fond. Mon travail de thèse s’est attaché à décomposer les situations de masquage pouvant apparaître au sein d’automobile ou de train, en complexifiant progressivement les stimuli au cours des mesures de masquage, en laboratoire. Un certain nombre de choix méthodologiques ont dû être effectués, limitant l’étude aux sons stationnaires, sans modulation d’amplitude, sans déphasage entre les oreilles.Nous nous sommes confrontés tout d’abord à la question du mode de reproduction. Nous avons souligné les difficultés rencontrées lors de la mesure de l’étalonnage des casques d’écoute. Nous avons validé l’écoute au casque étalonné au tympan, en comparant les mesures de seuils masqués de sons purs dans un bruit large bande, à une écoute en chambre sourde, face à une enceinte monophonique.Ensuite, nous avons complexifié le contenu spectral du masque en présentant des bruits comportant des tonalités marquées. Plusieurs modèles perceptifs ont été testés de façon à prédire l’élévation des seuils mesurés.Enfin, nous avons étudié l’amélioration à la détection d’un signal multifréquentiel et développé un modèle, issu de la théorie de la détection du signal, applicable aux signaux présentant des différences en niveau entre les composantes. L’influence du bruit masquant a également été révélé par la mesure de seuils de signaux multifréquentiels dans un bruit d’habitacle automobile. Un unique modèle de détection de signaux émergents, applicable aux signaux stationnaires, a été proposé. Ces travaux ouvrent de nombreuses perspectives, comme la poursuite du travail sur les émergences multifréquentielles, la prise en compte de la relation de phase entre les oreilles, l'étude des sons non stationnaires ou les phénomènes attentionels. / Emergences like tonal components take part in automobile and railroad acoustic comfort. These signals are totally or partially masked by the background noise, of automobile or train coaches. Determining the audibility of spectrally complex signals in a complex broadband noise masker, with tonalities or not, is yet an unanswered question and an industry expectation to characterize the overall sound quality of train/car cabins. The purpose of my PhD thesis was to measure detection thresholds for tones or complex tones, masked by a broadband noise, with pronounced tonal components or not. Several choices must have been performed, restricting study to stationary sounds, without modulation of amplitude, without inter-aural phase differences.First, different methods of sound reproduction are compared measuring detection thresholds. We underlined difficulties met during the measure of the calibration of headphones We validated the eardrum calibration, by comparing detection thresholds of pure sounds in a broad band noise, in a anechoic room, in front of a monophonic loudspeaker.Then, the masking thresholds of pure tones in the presence of maskers with pronounced tonal components are measured. Several perceptual models were tested in order to predict the elevation of the measured thresholds.Finally, we studied the improvement in detection of a multitone complex and developed a model to predict masking thresholds, based on the statistical summation model, applicable to multicomponent signals with differences in level between components. The influence of tonalities have been revealed with the car cabin noise.A threshold model, applicable to the stationary sounds, is proposed. Several perspectives are discussed, from time-variant signals to inter-aural differences or attention phenomena for example.

In der Metakontrastmaskierung wird die Sichtbarkeit des ersten Stimulus (Target) durch das Auftreten eines zweiten Stimulus (Maske) reduziert. Zwei Maskierungsfunktionen (MF) treten hauptsächlich auf: Typ A, wenn die Sichtbarkeit mit ansteigender SOA zumimmt, und Typ-B, wenn die Sichtbarkeit in kurzer und langer SOA hoch ist und auf ein Minimum in mittlerer SOA abfällt. In fünf Studien wurde systematisch untersucht welchen Einfluss experimentelle Parameter auf das Auftreten der MF haben. Je länger die Maske im Verhältnis zum Target präsentiert wird, desto weiter verschiebt sich das Minimum der MF hin zu kürzerer SOA und desto mehr ähnelt sie einer Typ-A-MF (monoton ansteigend). Die Maskierung ist in kleinen Stimuli stärker als in großen Stimuli, sowohl im Zentrum als auch in der Peripherie. Bei beiden Stimulusgrößen findet bei der kürzesten SOA die stärkste Maskierung statt. MF unterscheiden sich nicht, wenn sich die Vorhersagbarkeit der Präsentationsorte der Stimuli unterscheidet. Scheinbewegungen werden in langen SOAs eher wahrgenommen als in kurzen SOAs. Darüber hinaus wurden inter-individuelle Unterschiede gefunden, die Einblicke in die Mechanismen erlauben, die in der Metakontrastmaskierung beteiligt sind. Einige Versuchspersonen zeigen eine Typ-A-MF und berichten Scheinbewegungen in der Abfolge der Stimuli wahrzunehmen, hauptsächlich in langen SOAs. Andere zeigen eine Typ-B-MF und berichten negative Nachbilder in Form des Tagets im Inneren der Maske wahrzunehmen, hauptsächlich in kurzen SOAs. Typ-A- und Typ-B-Versuchspersonen unterscheiden sich in ihrer Top-Down-Verarbeitung der Stimuli, nicht aber in ihrer Bottom-Up-Verarbeitung. Zwei Prozesse stellten sich heraus, die in der Verarbeitung der Metakontraststimuli beteiligt sein könnten. Nach der Integrations-Segregations-Theorie steht die getrennte (segregierte) Wahrnehmung zweier Stimuli, die Scheinbewegungen ermöglicht, mit dem Segregationsprozess in Zusammenhang. Dagegen steht die gleichzeitige (integrierte) Wahrnehmung zweier nacheinander folgender Stimuli mit dem Integrationsprozess in Zusammenhang. Da Prozess 1 stark mit einer Typ-A-MF verknüpft ist, einhergehend mit der Wahrnehmung von Scheinbewegungen, könnte dieser Prozess dem Segregationsprozess entsprechen. Da Prozess 2 stark mit einer Typ-B-MF verknüpft ist, einhergehend mit der Wahrnehmung negativer Nachbilder, könnte dieser Prozess dem Integrationsprozess entsprechen. Es wird angenommen, dass diese beiden Prozesse an der bewussten Wahrnehmung des Targets in der Metakontrastmaskierung beteiligt sind.

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Esta pesquisa compartilha processos pedagógicos de criação de dramaturgia(s) que se desenvolvem por meio das relações entre os mascaramentos corporais dos artistas, o espaço da rua e os transeuntes-espectadores. Apresento uma dramaturgia pensada de forma expandida e processual, que se define pelos deslocamentos e infiltrações desses corpos mascarados no espaço urbano, pela organização das ações dos performers mascarados em jogo com o Espaço e com um público efêmero, que observa e segue, levando consigo suas percepções. A imprevisibilidade, o imponderável, a presença do performer que age motivado por suas questões subjetivas, políticas, sociais, e não por um personagem que irá representar, estão presentes nesse processo de criação fazendo parte dos procedimentos artísticos e pedagógicos propostos, fundamentados nas ideias de Josette Féral, acerca do \"teatro performativo\" e \"teatralidades cotidianas\", e nas ideias de \"multiestabilidade perceptiva\", de Érika Fischer-Lichte, quando fala sobre o espectador que se encontra em um \"entre\" a \"ordem de representação\" e a \"ordem da presença\". / This research benefits from pedagogical processes of creation of dramaturgy (s) which is developed through the interaction of the \'body masks\' of the artist, the \'passers-by-spectators\' and the public space. I present a dramaturgy thought in an expanded and procedural way, defined by the displacement and infiltrations of these masked bodies in urban space, by the organization of the actions of the masked performers interacting with space and with an ephemeral audience that observes and follows, taking with them their perceptions. The unpredictability, the imponderable, the presence of the performer who acts motivated by his subjective, political, and social issues, and not by a character that will play, are present in this process of creation. Thus being part of the artistic and pedagogical procedures proposed. This is based on the ideas of Josette Féral about the \"performative theater\" and \"daily theatricalities\", and Érika Fischer-Lichte\'s ideas of \"perceptual multistability\", when she talks about the spectator who is in \"between\" the \"order of representation\" and the \"order of presence\".

Esta pesquisa compartilha processos pedagógicos de criação de dramaturgia(s) que se desenvolvem por meio das relações entre os mascaramentos corporais dos artistas, o espaço da rua e os transeuntes-espectadores. Apresento uma dramaturgia pensada de forma expandida e processual, que se define pelos deslocamentos e infiltrações desses corpos mascarados no espaço urbano, pela organização das ações dos performers mascarados em jogo com o Espaço e com um público efêmero, que observa e segue, levando consigo suas percepções. A imprevisibilidade, o imponderável, a presença do performer que age motivado por suas questões subjetivas, políticas, sociais, e não por um personagem que irá representar, estão presentes nesse processo de criação fazendo parte dos procedimentos artísticos e pedagógicos propostos, fundamentados nas ideias de Josette Féral, acerca do \"teatro performativo\" e \"teatralidades cotidianas\", e nas ideias de \"multiestabilidade perceptiva\", de Érika Fischer-Lichte, quando fala sobre o espectador que se encontra em um \"entre\" a \"ordem de representação\" e a \"ordem da presença\". / This research benefits from pedagogical processes of creation of dramaturgy (s) which is developed through the interaction of the \'body masks\' of the artist, the \'passers-by-spectators\' and the public space. I present a dramaturgy thought in an expanded and procedural way, defined by the displacement and infiltrations of these masked bodies in urban space, by the organization of the actions of the masked performers interacting with space and with an ephemeral audience that observes and follows, taking with them their perceptions. The unpredictability, the imponderable, the presence of the performer who acts motivated by his subjective, political, and social issues, and not by a character that will play, are present in this process of creation. Thus being part of the artistic and pedagogical procedures proposed. This is based on the ideas of Josette Féral about the \"performative theater\" and \"daily theatricalities\", and Érika Fischer-Lichte\'s ideas of \"perceptual multistability\", when she talks about the spectator who is in \"between\" the \"order of representation\" and the \"order of presence\".

"The process of securing data has always been a challenge since it is related to the safety of people and society. Nowadays, there are many cryptographic algorithms developed to solve security problems. However, some applications have constraints which make it difficult to achieve high levels of security. Light weight cryptography aims to address this issue while trying to maintain low costs. Side-channel attacks have changed the way of cryptography significantly. In this kind of attacks, the attacker has physical access to the crypto-system and can extract the sensitive data by monitoring and measuring the side-channels such as power consumption, electromagnetic emanation, timing information, sound, etc. These attacks are based on the relationship between side-channels and secret data. Therefore, there need to be countermeasures to eliminate or reduce side channel leaks or to break the relationship between side-channels and secret data to protect the crypto systems against side-channel attacks. In this work, we explore the practicality of Threshold Implementation (TI) with only two shares for a smaller design that needs less randomness but is still leakage resistant. We demonstrate the first two-share Threshold Implementations of light-weight block cipher Present. Based on implementation results, two-share TI has a lower area overhead and better throughput when compared with a first-order resistant three-share scheme. Leakage analysis of the developed implementations reveals that two-share TI can retain perfect first-order resistance. However, the analysis also exposes a strong second-order leakage. "

OBJECTIVES: The aims of this study are to determine the shade correlation between try-in pastes with their corresponding resin cements. Also, to investigate the effect of resin cement shades and various ceramic thicknesses, shades, and translucency in the final color outcome over tooth-shaded backgrounds. MATERIALS AND METHOD: Lithium Disilicate CAD/CAM blocks (IPS e.max CAD) were prepared, in high and low translucency, in two different shades (A1 and A3), and in 2 different thicknesses (0.53 ± 0.02 mm and 0.83 ± 0.02 mm). Four different tooth-shaded backgrounds (ND2, ND5, ND8, and ND9) were prepared from acrylic resin in a standard thickness of 6.610 mm to achieve complete opacity. RelyX veneer cement and its corresponding try-in paste in three different shades, Transparent (TR), White Opaque (WO), and Bleached Opaque (BO), in a thickness of (80 ± 5 μm) were used. For each combination, the color was measured with a spectrophotometer to calculate the color difference (ΔΕ value) in reference to ceramic veneer, and the differences of ΔΕ among the specimens were compared statistically using JMP Pro 13. Analysis was performed for 3 aims, (1) to compare the ability of ceramic to mask the aspect of the abutment in relation to its thickness (0.5 and 0.8) mm, transparency (HT and LT) and shade (A1 and A3), (2) effect of a change in cement color (TR, WO, and BO) on the final color of the ceramic; and (3) to determine the correlation between try-in pastes with their corresponding resin cements. RESULT: A significant difference was found with a p-value of <.0001 for the following factors: Stump Shade, ceramic thickness, cured cement, ceramic shade, cement type and for the interactions of cured cement with cement type, and stump shade with ceramic transparency. Also, a significant difference was found with ceramic transparency with a p-value 0.0476. While cured cement and its corresponding try-in paste showed a significant difference in color masking (p <.0001) shade White Opaque cement and shade White Opaque try-in paste exhibited insignificant color change outcome with a p-value of 0.8051. CONCLUSION: RelyX veneer cements shades (Translucent and Bleached Opaque) have lower masking ability than White Opaque cement. RelyX veneer Try in paste is much less effective in masking than its corresponding resin cement. The only correlation between RelyX veneer cements with their corresponding try-in pastes among the shades tested (White Opaque, Translucent and Bleached Opaque) is with shade White Opaque. This study demonstrated that underlying tooth abutment color, cement color, and ceramic thickness, shade and translucency all influence the resulting optical color of CAD/CAM glass-ceramic lithium disilicate-reinforced restorations. / 2020-10-24T00:00:00Z

<p>A common problem of hearing aids is whistling caused by feedback from the loudspeaker back to the microphone. A method of reducing the negative effects, caused by the feedback, is called feedback cancellation. A variant of feedback cancellation uses a probe signal, which is applied to the speaker of the hearing aid and is used to continuously estimate the feedback. Oticon A/S has suggested a master's thesis with the purpose of designing and evaluating an algorithm generating a probe signal for feedback cancellation systems. The challenge was to find an inaudible probe signal with as much energy as possible. </p><p>Two approaches have been investigated for generating a probe signal. In the first approach the psychoacoustic principle of masking was used to estimate how much noise that could be added to a signal without being heard. Psychoacoustic models, including masking, are used in MPEG (Moving Pictures Expert Group) audio coding and one of these models has been examined in the thesis. In the second approach a standard LPC (Linear Prediction Coding) algorithm was used. In both the MPEG and the LPC approach, warped signal processing has been utilized improving the methods. </p><p>A listening test was performed, evaluating the methods generating the probe signal. The purpose of the test was to determine whether the noise, generated using the MPEG and LPC approach, was inaudible. A hearing aid system with feedback cancellation, using the probe signal, was also simulated. The listening test showed that the noise (probe signal) had to be lowered, much more than expected, to be inaudible. As a consequence, shown in the simulations, the feedback cancellation system, using the probe signal, had trouble identifying the feedback of the hearing aid.</p>

We describe here, briefly, a perceptual non-reading measure which reliably distinguishes between dyslexic persons and ordinary readers. More importantly, we describe a regimen of practice with which dyslexics learn a new perceptual strategy for reading. Two controlled experiment on dyslexics children demonstrate the regimen's efficiency.

Response times have been used to explore cognitive and perceptual processes since 1850 (Donders, 1868). The technique has primarily been applied to humans, birds, and terrestrial mammals. Results from two studies are presented here that examine response times in bottlenose dolphins (Tursiops truncatus) and white whales (Delphinapterus leucas). One study concerned response times to stimuli well above the threshold of perceptibility of a stimulus, and the other concerned response times to stimuli near threshold. Two white whales (Delphinapterus leucas) and five Atlantic bottlenose dolphins (Tursiops truncatus) were presented stimuli well above threshold. The stimuli varied in type (tone versus pulse), amplitude, duration, and frequency. The average response time for bottlenose dolphins was 231.9 ms. The average response time for white whales was 584.1 ms. There was considerable variation between subjects within a species, but the difference between species was also found to be significant. In general, response times decreased with increasing stimulus amplitude. The effect of duration and frequency on response time was unclear. Two white whales (Delphinapterus leucas) and four Atlantic bottlenose dolphins (Tursiops truncatus) were given audiometric tests to determine masked hearing thresholds in open waters of San Diego Bay (Ridgway et al., 1997). Animals were tested at six frequencies over a range from 400 Hz to 30 kHz using pure tones. Hearing thresholds varied from 87.5 dB to 125.5 dB depending on the frequency, masking noise intensity and individual animal. At threshold, median response time across frequencies within each animal varied by about 150 ms. The two white whales responded significantly slower (∼670 msec, p<0.0001) than the four dolphins (∼410 msec). As in terrestrial animals, reaction time became shorter as stimulus amplitude increased (Wells, 1913; Stebbins, 1966). Across the two studies, the dolphins as a group were faster in the abovethreshold study than in the nearthreshold study. White whales had longer response times than bottlenose dolphins in both studies. Analysis of response time with an allometric relation based on weight shows that the difference in weight can explain a significant part of the difference in response time.