La séparation de sources consiste à extraire des signaux appelés sources à partir seulement de mélanges observés de ces signaux appelés observations. De nombreuses approches ont été brièvement présentées dans ce manuscrit. La plupart de ces approches exploite l'hypothèse d'indépendance des sources.<br />Dans cette thèse, nous avons considéré le cas des mélanges linéaires convolutifs. Nous proposons de calculer les contributions des sources sur les capteurs afin d'optimiser la procédure de séparation.<br />L'estimation des contributions dans les observations est réalisée grâce à un critère quadratique optimisé par un filtre de Wiener. Ensuite, nous étudions deux approches de séparation de sources. <br />La première utilise l'information mutuelle comme critère d'indépendance et la seconde dite fonction de contraste est basée sur les statistiques d'ordre quatre. L'utilisation des contributions des sources sur les capteurs dans la phase de séparation nous permet de proposer deux algorithmes de séparation, qui constituent deux généralisations d'algorithmes classiques.

Experiments were conducted to investigate the punching shear behaviour of thick slabs with identical spans and depths, subjected to monotonic point load conditions. Variables included: reinforcement ratio, column size, and reinforcement size. Analytical studies conducted as part of this thesis indicate that the current CSA A23.3 and the ACI 318 can be unconservative for thick slabs with low reinforcement ratios. The new fib Model Code provisions for punching offer an effective method for determining the full load-rotation behaviour of a slab up to failure, including accurate failure predictions. A summary of the background of current design procedures and standards will be presented, and a comparison between the different design equations and theories will be given. Based on the findings of this project, it is proposed that the provisions accepted by the fib Model Code should be considered for implementation in the CSA and ACI standards.

Experiments were conducted to investigate the punching shear behaviour of thick slabs with identical spans and depths, subjected to monotonic point load conditions. Variables included: reinforcement ratio, column size, and reinforcement size. Analytical studies conducted as part of this thesis indicate that the current CSA A23.3 and the ACI 318 can be unconservative for thick slabs with low reinforcement ratios. The new fib Model Code provisions for punching offer an effective method for determining the full load-rotation behaviour of a slab up to failure, including accurate failure predictions. A summary of the background of current design procedures and standards will be presented, and a comparison between the different design equations and theories will be given. Based on the findings of this project, it is proposed that the provisions accepted by the fib Model Code should be considered for implementation in the CSA and ACI standards.

With National Telecommunications & Information Administration (NTIA) Advanced Wireless Services (AWS-3) auction of frequencies in the 1695-1710 MHz, 1755-1780MHz, and 2155- 2180MHz bands, users of the Aeronautical Mobile Telemetry (AMT) band from 1755- 1850MHz, known as Upper L-Band, could be greatly affected. This paper takes an initial look at how the 1755-1780MHz band will be used by the cellular carriers and presents some preliminary testing results of adjacent channel (band) interference that could be experienced by AMT users. This paper should be considered as the stepping off point for future interference discussions, required analysis, and further testing.

The study evaluated the effects of genotype and grainless diets under stall-fed (n=72) conditions on the following parameters using the Afar, Central Highland goats, (CHG) and Long-eared Somali, (LES) goats. The diets varied in concentrate: roughage ratios. Diet 1 was a 50: 50 ratio (8.5 MJ ME/kg DM), Diet 2, 65:35 (9.2 MJ ME/kg DM) and Diet 3 an 80:20 ratio (10 MJ ME/kg DM), respectively. The same genotypes reared under the extensive grazing systems were also evaluated. Intake, feed efficiency (FE) and rumen parameters Total DMI ranged between 2.6 and 3.0 % on a body weight basis and between 53.5 and 62.3 g per kg metabolic body weight. The LES had a higher (P<0.001) DM roughage intake, total DMI (P<0.01) and FE (P<0.05). Goats on Diet 3 had higher (P<0.001) total DMI (g/d). Diet 1 however, displayed higher (P>0.05) FE. The mean concentration of NH3-N (39.4-53.7 mg/100ml rumen fluid) was above the N requirements for optimal microbial activity. The mean pH was similar between diets and ranged from 6.43 to 6.63. Total VFA was depressed (P<0.01) with increased grainless concentrate in the diet. Diet 1 recorded a higher (P<0.01) total VFA and lower (P<0.01) NH3-N concentration, indicating that feed nitrogen was more efficiently utilized in Diet 1. The molar proportions of acetate, propionate and butyrate varied (P>0.05) from 64.5 to 65.7, 17.7 to 18.8 and 10.7 to 12.8%, respectively. The ratio of acetic: propionic was not affected by diet (P>0.05) and ranged from 3.5 to 3.81. The values for degradation constants were similar (P>0.05) between the diets. However, the hay DM and neutral detergent fibre were more degradable (P<0.05) in goats fed Diet 1. Differences in DMI and FE between the genotypes were recorded with the LES breed being superior. Among the grainless diets, the 50:50 ratio created a favorable rumen environment and resulted in a better FE under a feedlot system. Carcass characteristics and meat quality of extensively managed goats Genotypes were similar (P>0.05) for most of carcass traits, at an average slaughter weight of 13.8 kg. The genotypes had a mean hot carcass weight of 5.9 kg and a dressing percentage (DP) on a slaughter body weight basis of 42.8%. The CHG had a 52% higher (P<0.01) chilling loss than the other genotypes. The rib physical composition was similar between genotypes, except for fat proportion. The CHG had the lowest (P<0.05) fat proportion. The chemical composition was similar between the genotypes, with the CHG having the lowest (P>0.05) chemical fat percentage. The composition of most muscle fatty acids was affected by genotype. The LES breed presented a beneficial ratio of n-6: n-3 PUFA favorable to consumers’ health. The goats under the extensive system in general, were characterized by a lower carcass weight and poor carcass fat cover. Hence, to improve the carcass characteristics it is essential that grazing goats should be supplemented or stall-fed with locally available concentrates depending on the grazing resources of the agro-ecologies and the objectives of the goat farmers. Growth and carcass characteristics of stall-fed goats The LES breed had significantly higher growth rates (ADG), heavier pre-slaughter, slaughter, empty body weight (EBW) and carcass weights than the Afar and CHG goats. Effect of diet was also significant on ADG, but similar for carcass traits, except for DP on EBW basis and some non-carcass components. The DP on an EBW basis, was the highest (P<0.01) for Diet 1. Stall-feeding of the goats improved the mean carcass weight by 38% over the initial slaughtered groups. Genotype affected the DP and it ranged from 42.5 to 44.6% and 54.3 to 55.8% on a slaughter weight and on EBW basis, respectively. The ultimate carcass pH was between 5.61 and 5.67 and chilling losses ranged from 2.5 to 3.1 %. The rib physical composition (fat and bone) differed between genotype and ranged from 72-73 %, 6.9-10.9% and 17.1-20.2% for muscle, fat and bone respectively. The findings indicate that breed differences were reflected in carcass characteristics. Meat quality of stall-fed goats Genotype significantly influenced the carcass fat and crude protein (CP) concentration, with the values ranging from 10.3 to 14.0% and 19.3 to 21.1%, respectively. The Afar and LES goats had higher fat concentration (P<0.001) compared to the CHG while the CP was higher (P<0.01; P<0.05) for the CHG. The effect of diet was significant on CP%, but was similar for fat concentration although Diet 3 tended to have a higher value. Cooking and drip loss differed (P<0.01, P<0.05) between genotypes and both traits increased with increased fatness. The effect of diet however, was similar for cooking and drip loss. Genotype and diet significantly influenced the composition of most muscle fatty acids. An interaction between genotype and diet was also exhibited on certain fatty acids. Compared to CHG, Afar and LES breeds had a higher PUFA, MUFA and UFA: SFA ratio, which are considered healthier for human consumption due to their lowering effect of cholesterol content. The relatively higher carcass fat, which is useful in reducing chilling loss and improves eating quality, the absence of C12:0 and lower concentration of C14:0, hypercholesterolemic, and higher C18:1, hypocholesterolemic fatty acids, are some of the important traits observed in Ethiopian goats. These findings suggest that a potential exists in the use of Ethiopian goat breeds fed a grainless diet, for the production of meat with specific quality characteristics. / Thesis (PhD (Animal Science))--University of Pretoria, 2008. / Animal and Wildlife Sciences / unrestricted

Certaines études ont montré que des odeurs subliminales – odeurs d'intensité très faible activant le système olfactif mais non perçues consciemment – peuvent impacter le comportement alimentaire. Cependant, les mécanismes sensoriels et cognitifs impliqués dans le traitement des odeurs subliminales demeurent mal connus. Ce travail de thèse avait pour but d'explorer les activations cérébrales induites par des odeurs subliminales au moyen de l'Imagerie par Résonance Magnétique fonctionnelle. Durant les acquisitions IRM, les participants sont exposés à leur insu à deux odeurs présentées à intensité subliminale puis supraliminale. Quatre réseaux cérébraux mis en évidence par Analyse en Composantes Indépendantes s’avèrent spécifiques de la condition subliminale. Ces réseaux ne sont pas propres au traitement des odeurs et semblent liés à des processus attentionnels et de contrôle exécutif. La modulation de leur activité par des odeurs subliminales apporte des éléments nouveaux pour comprendre l’impact de ces odeurs sur le comportement, et suggère des applications possibles d'utilisation de ces odeurs pour réguler le comportement alimentaire. / Some studies showed that subliminal odours – odours of very low intensity which activate the olfactory system but are not consciously perceived – can impact food behaviours. However, the sensory and cognitive mechanisms involved in subliminal odours processing remain poorly known. This work aims exploring cerebral activity induced by subliminal odours by the means of functional Magnetic Resonance Imaging. During MRI acquisitions, participants were unknowingly exposed to two odours presented at subliminal intensity and then at supraliminal intensity. Four cerebral networks highlighted by Independent Component Analysis (ICA) prove to be specific to the subliminal condition. These networks are not particular to olfactory processing and seem to be linked to attentional and executive control processes. The modulation of their activity by subliminal odours brings new elements to understand the impact of these odours on behaviour, and suggests possible applications for using these odours to regulate food behaviour.

Coral reefs around the world are threatened by a variety of sources, from localized impacts, including overfishing and coastal development, to global temperature increases and ocean acidification. Conserving these marine biodiversity havens requires both global and local action informed by scientific research. In this thesis, I use data collected from the coral reefs around Kiritimati atoll (Republic of Kiribati) in the central equatorial Pacific, first to assess the applicability of two common metrics used in passive underwater acoustic research, and second to examine the effects of a marine heatwave and local human disturbance on an assemblage of corallivorous fish. Using acoustic data recorded in 2017 and 2018 on reefs around Kiritimati, I assess how sound pressure level (SPL) and the acoustic complexity index (ACI) respond to changes in fish sounds in a low frequency band (160 Hz – 1 kHz) and snapping shrimp snaps in a high frequency band (1 kHz – 22 kHz). I found that while SPL was positively correlated with increases in fish sounds and snap density, changes in ACI were dependent upon the settings chosen for its calculation, with the density of snaps negatively correlated with ACI across all settings. These findings provide evidence that despite its quick and prolific adoption, acoustic metrics like ACI should be thoroughly field-tested and standardized before they are applied to new ecosystems like coral reefs. Next, using underwater visual censuses (UVCs) of reef fish assemblages, I quantified how two functional groups of corallivores, obligate and facultative, responded to a mass coral mortality event created by the 2015-2016 El Niño. Declines in abundance of both groups were largely driven by the response of coral-associated damselfishes, Plectroglyphidodon johnstonianus in the obligate group and Plectroglyphidodon dickii in the facultative group, to heat stress and subsequent coral mortality. I also observed a significant decline in the species richness of obligate corallivores, and a continued decline in the abundance of obligate corallivores three years after the mass coral mortality event. Additionally, facultative corallivore abundance increased with disturbance, although the effect was modulated by year, likely due to their more adaptable diets. Corallivore assemblage structure was also influenced by the heat stress event, recovery, and local human disturbance. These results detail how an entire corallivorous assemblage is impacted by a coral mortality event and incidentally provide a timeline for corallivore decline. Together, these results provide information about new ways of monitoring coral reefs, and the ways in which two components of the reef fish community, obligate and facultative corallivores, respond to a mass coral mortality event. / Graduate / 2022-01-15

Syftet med denna undersökning är att undersöka hur glanceable feedback kan implementeras i aktivitetsenheter för hundar för att skapa en bättre användarupplevelse och minska den teknologiska störningen i kommunikationen mellan människa och hund. Tidigare studier visar att utvecklingen hos aktivitetsenheter för hundar är långt ifrån lika framgångsrik jämfört med den för aktivitetsenheter för människor (Ramokapane, van der Linden &amp; Zamansky, 2019; Väätäjä et al. 2018; Zamansky; et al. 2019). Väätäjä, et al. (2018) har påpekat vikten av att teknologin bakom aktivitetsenheten, så som mobiltelefoner, inte ska komma mellan hundägaren och hunden. Den får inte agera som ett störningsmoment som distanserar kommunikation eller interaktion mellan hund och människa (Väätäjä et al. 2018). Detta är idag oundvikligt i dagens aktivitetsenheter för hundar då användaren är helt beroende av mobiltelefonens tillhörande applikation (Väätäjä et al. 2018). Genom frågeställningen (Hur kan glanceable feedback appliceras i aktivitetsenhet för hundar för att ge hundägaren direkt information om hundens aktivitet?) undersöks hur glanceable feedback kan appliceras i aktivitetsenheter för hundar och undvika att kommunikation mellan hund och ägare störs med tekniken. Resultatet är aktivitetsenheten Good Boy. Enheten är försedd med en display och ett mekaniskt hjul som byter mellan de olika kategorierna distans/steg, puls/kroppstemperatur, info/kontaktuppgifter och led/lampa. / The purpose of this study is to investigate how glanceable feedback can be implemented in activity units for dogs to create a better user experience and reduce the technological disruption in human-dog communication. Previous studies show that the development of activity units for dogs is far from as successful as activity units for humans (Ramokapane, van der Linden &amp; Zamansky, 2019; Väätäjä et al. 2018; Zamansky et al. 2019). Väätäjä, et al. (2018) have pointed out the importance of the technology behind the activity, such as the mobile phone, unit not coming between the dog owner and the dog. It must not act as a disturbance that distances communication or interaction between dog and human (Väätäjä et al. 2018). This is inevitable in today's activity units for dogs as the user is completely dependent on the mobile phone's associated application (Väätäjä et al. 2018).  The question (How can glanceable feedback be applied in an activity unit for dogs to give the dog owner direct information on the dog's activity?) Investigates how glanceable feedback can be applied in activity units for dogs and avoid that communication between dog and owner is disturbed by technology. The result is the Good Boy activity unit. The unit is equipped with a display and a mechanical wheel that switches between the different categories distance / step, pulse / body temperature, info /contact information and LED/lamp.

No description available.

Esta dissertação contempla o estudo sobre os principais aspectos que norteiam as propostas normativas com critérios de dimensionamento de estruturas de concreto armado reforçadas com Polímeros Reforçados com Fibras (FRP). Este trabalho procura avaliar e discutir as metodologias de cálculo sugeridas pelas publicações American Concrete Institute (ACI) \"Committee 440\" e Fédération Internationale du béton (FIB) e propor um procedimento para a análise e dimensionamento do reforço aos esforços de flexão e discutir a importância do esforço cortante com relação à flexão. Primeiramente, efetuou-se uma revisão bibliográfica sobre o estado da arte no que concerne ao dimensionamento de reforços com materiais compósitos de FRP. Em seguida, apresentou-se a análise da verificação de segurança de elementos reforçados à flexão segundo a perspectiva das publicações acima mencionadas: ACI440.2R (2017) e FIB Model Code (2010). Posteriormente, estabeleceu-se um estudo de análise comparativa entre os resultados experimentais encontrados na bibliografia, os previstos pelos referidos manuais para os modelos aqui estudados. Os valores máximos da capacidade resistente dos modelos serão confrontados e a importância do conhecimento das características dos materiais discutidos. Com tais informações sistematizaram-se os procedimentos de cálculo a se adotar em um projeto de reforço estrutural com sistemas compósitos de FRP, respeitando as propostas normativas que mais se adequam ao Brasil. / The present dissertation results from a study concerning the main design criteria for reinforced concrete structures through externally bonding Fibre-Reinforced Polymer (FRP) systems. This paper tries to evaluate and discuss the design methodologies proposed by the guidelines publications American Concrete Institute (ACI) \"Committee 440\" and Fédération Internationale du béton (FIB) and seek to propose a procedure for the analysis and design of FRP strengthened RC elements in bending and discuss the importance of shear stress regarding the bending efforts. Initially, a state-of-art concerning design criterias on the use of FRP composites is presented. Then, the analysis and procedures of the safety concept is exposed from the perspective of the publications: ACI440.2R (2017) and FIB Model Code 2010. After, it established a study of comparative analysis between the experimental results found in the bibliography and the ones predicted by international guidelines for beams and slabs. The maximum ultimate capacity of the strengthened element will be compared and confronted and the importance of the knowledge of the characteristics of the materials discussed. Finally, conclusions are drawn out and recommendations concerning the design and safety concepts are presented, respecting the guidelines proposals that are most appropriate to Brazil.