Fundamento: Recomendações para controle da hipertensão contemplam controle de peso, restrição de sódio e consumo de bebidas alcoólicas, além de adesão à dieta DASH (Dietary Approaches to Stop Hypertension). Objetivo: Avaliar a associação entre consumo de dieta tipo DASH e pressão arterial, na população adulta de Porto Alegre. População e Métodos: Estudo transversal (Síndrome de Obesidade e Fatores de Risco para Obesidade -SOFT), desenvolvido em uma amostra populacional, incluiu 1629 indivíduos com 18 a 90 anos de idade. Entrevistas domiciliares foram feitas por entrevistadores treinados, utilizando-se instrumentos padronizados que incluíam questionário de freqüência alimentar validado na mesma população. Foram aferidos peso e altura, além de pressão arterial (quatro medidas), utilizando-se equipamento automático (OMRON CP705). Estimouse a ingestão diária e foram calculados os grupos alimentares de frutas, vegetais, laticínios dietéticos e grãos integrais, que constituíram o Escore DASH. Análise de variância, regressão linear múltipla e regressão logística foram utilizadas para as análises. Resultados: Cerca de 21% da população ingeriu dieta tipo DASH. Indivíduos no quintil inferior de consumo de frutas apresentaram médias de pressão sistólica (129,4 ±1,1 mmHg) e diastólica (78,2 ±0,7 mmHg) superiores às do quintil mais elevado (125,3 ±1.1 and 76,9 ±0,7 mmHg, respectivamente), o mesmo aplicando-se a laticínios totais e dietéticos e grãos integrais (apenas para pressão sistólica). Escore DASH associou-se inversamente com hipertensão; comparativamente ao quintil superior, participantes situados no primeiro quintil apresentaram risco independente cerca de quatorze vezes maior (OR= 14,4; 95%CI: 1,8- 117,9). Conclusões: População adulta de Porto Alegre consome componentes da dieta DASH, mas apenas um quinto apresentou padrão tipo DASH, confirmando-se os benefícios sobre a pressão arterial em contexto populacional. / Background: Recommendations for the control of hypertension include weight control, the restriction of sodium intake and the consumption of alcoholic beverages, as well as adherence to the Dietary Approaches to Stop Hypertension (DASH). Objective: To evaluate the association between consumption of a DASH-type diet and blood pressure within the adult population of Porto Alegre, Brazil. Population and Methods: A cross-sectional study was conducted in a population-based sampling of 1629 adults between 18 and 90 years old. Interviews were conducted at participants’ homes by certified interviewers, using standardized protocols, including a food frequency questionnaire validated for this population. Weight and height were measured, in addition to blood pressure (four measurements), using a automated validate device (OMRON CP-705). Daily dietary intakes were estimated and categorized into the alimentary groups of fruits, vegetables, dairy products and whole grains that make up the DASH score. Analyses of variance, multiple linear regression, and multivariate logistic regression were undertaken for this study. Results: Approximately 21% of the population consumed a DASH-type diet. Individuals in the lower quintile of fruit consumption had higher systolic (129.4 ±1.1 mmHg) and diastolic means (78.2 ±0.7 mmHg) than those in the higher quintile (125.3 ±1.1 and 76.9 ±0.7 mmHg, respectively), as well as those participants who consumed regular and low-fat dairy products and of whole grains (for systolic pressure only). The DASH score was inversely and independently associated with hypertension; participants situated in the lower category had nearly fourteen times greater risk than those in the higher category (OR= 14.4; 95%CI: 1.8- 117.9). Conclusions: The adult population of Porto Alegre consumed groups of the DASH diet, but only one fifth presented a DASH-type diet. The present findings confirm the benefits of the DASH diet on blood pressure in a non-intervention setting.

Fundamento: Recomendações para controle da hipertensão contemplam controle de peso, restrição de sódio e consumo de bebidas alcoólicas, além de adesão à dieta DASH (Dietary Approaches to Stop Hypertension). Objetivo: Avaliar a associação entre consumo de dieta tipo DASH e pressão arterial, na população adulta de Porto Alegre. População e Métodos: Estudo transversal (Síndrome de Obesidade e Fatores de Risco para Obesidade -SOFT), desenvolvido em uma amostra populacional, incluiu 1629 indivíduos com 18 a 90 anos de idade. Entrevistas domiciliares foram feitas por entrevistadores treinados, utilizando-se instrumentos padronizados que incluíam questionário de freqüência alimentar validado na mesma população. Foram aferidos peso e altura, além de pressão arterial (quatro medidas), utilizando-se equipamento automático (OMRON CP705). Estimouse a ingestão diária e foram calculados os grupos alimentares de frutas, vegetais, laticínios dietéticos e grãos integrais, que constituíram o Escore DASH. Análise de variância, regressão linear múltipla e regressão logística foram utilizadas para as análises. Resultados: Cerca de 21% da população ingeriu dieta tipo DASH. Indivíduos no quintil inferior de consumo de frutas apresentaram médias de pressão sistólica (129,4 ±1,1 mmHg) e diastólica (78,2 ±0,7 mmHg) superiores às do quintil mais elevado (125,3 ±1.1 and 76,9 ±0,7 mmHg, respectivamente), o mesmo aplicando-se a laticínios totais e dietéticos e grãos integrais (apenas para pressão sistólica). Escore DASH associou-se inversamente com hipertensão; comparativamente ao quintil superior, participantes situados no primeiro quintil apresentaram risco independente cerca de quatorze vezes maior (OR= 14,4; 95%CI: 1,8- 117,9). Conclusões: População adulta de Porto Alegre consome componentes da dieta DASH, mas apenas um quinto apresentou padrão tipo DASH, confirmando-se os benefícios sobre a pressão arterial em contexto populacional. / Background: Recommendations for the control of hypertension include weight control, the restriction of sodium intake and the consumption of alcoholic beverages, as well as adherence to the Dietary Approaches to Stop Hypertension (DASH). Objective: To evaluate the association between consumption of a DASH-type diet and blood pressure within the adult population of Porto Alegre, Brazil. Population and Methods: A cross-sectional study was conducted in a population-based sampling of 1629 adults between 18 and 90 years old. Interviews were conducted at participants’ homes by certified interviewers, using standardized protocols, including a food frequency questionnaire validated for this population. Weight and height were measured, in addition to blood pressure (four measurements), using a automated validate device (OMRON CP-705). Daily dietary intakes were estimated and categorized into the alimentary groups of fruits, vegetables, dairy products and whole grains that make up the DASH score. Analyses of variance, multiple linear regression, and multivariate logistic regression were undertaken for this study. Results: Approximately 21% of the population consumed a DASH-type diet. Individuals in the lower quintile of fruit consumption had higher systolic (129.4 ±1.1 mmHg) and diastolic means (78.2 ±0.7 mmHg) than those in the higher quintile (125.3 ±1.1 and 76.9 ±0.7 mmHg, respectively), as well as those participants who consumed regular and low-fat dairy products and of whole grains (for systolic pressure only). The DASH score was inversely and independently associated with hypertension; participants situated in the lower category had nearly fourteen times greater risk than those in the higher category (OR= 14.4; 95%CI: 1.8- 117.9). Conclusions: The adult population of Porto Alegre consumed groups of the DASH diet, but only one fifth presented a DASH-type diet. The present findings confirm the benefits of the DASH diet on blood pressure in a non-intervention setting.

Fundamento: Recomendações para controle da hipertensão contemplam controle de peso, restrição de sódio e consumo de bebidas alcoólicas, além de adesão à dieta DASH (Dietary Approaches to Stop Hypertension). Objetivo: Avaliar a associação entre consumo de dieta tipo DASH e pressão arterial, na população adulta de Porto Alegre. População e Métodos: Estudo transversal (Síndrome de Obesidade e Fatores de Risco para Obesidade -SOFT), desenvolvido em uma amostra populacional, incluiu 1629 indivíduos com 18 a 90 anos de idade. Entrevistas domiciliares foram feitas por entrevistadores treinados, utilizando-se instrumentos padronizados que incluíam questionário de freqüência alimentar validado na mesma população. Foram aferidos peso e altura, além de pressão arterial (quatro medidas), utilizando-se equipamento automático (OMRON CP705). Estimouse a ingestão diária e foram calculados os grupos alimentares de frutas, vegetais, laticínios dietéticos e grãos integrais, que constituíram o Escore DASH. Análise de variância, regressão linear múltipla e regressão logística foram utilizadas para as análises. Resultados: Cerca de 21% da população ingeriu dieta tipo DASH. Indivíduos no quintil inferior de consumo de frutas apresentaram médias de pressão sistólica (129,4 ±1,1 mmHg) e diastólica (78,2 ±0,7 mmHg) superiores às do quintil mais elevado (125,3 ±1.1 and 76,9 ±0,7 mmHg, respectivamente), o mesmo aplicando-se a laticínios totais e dietéticos e grãos integrais (apenas para pressão sistólica). Escore DASH associou-se inversamente com hipertensão; comparativamente ao quintil superior, participantes situados no primeiro quintil apresentaram risco independente cerca de quatorze vezes maior (OR= 14,4; 95%CI: 1,8- 117,9). Conclusões: População adulta de Porto Alegre consome componentes da dieta DASH, mas apenas um quinto apresentou padrão tipo DASH, confirmando-se os benefícios sobre a pressão arterial em contexto populacional. / Background: Recommendations for the control of hypertension include weight control, the restriction of sodium intake and the consumption of alcoholic beverages, as well as adherence to the Dietary Approaches to Stop Hypertension (DASH). Objective: To evaluate the association between consumption of a DASH-type diet and blood pressure within the adult population of Porto Alegre, Brazil. Population and Methods: A cross-sectional study was conducted in a population-based sampling of 1629 adults between 18 and 90 years old. Interviews were conducted at participants’ homes by certified interviewers, using standardized protocols, including a food frequency questionnaire validated for this population. Weight and height were measured, in addition to blood pressure (four measurements), using a automated validate device (OMRON CP-705). Daily dietary intakes were estimated and categorized into the alimentary groups of fruits, vegetables, dairy products and whole grains that make up the DASH score. Analyses of variance, multiple linear regression, and multivariate logistic regression were undertaken for this study. Results: Approximately 21% of the population consumed a DASH-type diet. Individuals in the lower quintile of fruit consumption had higher systolic (129.4 ±1.1 mmHg) and diastolic means (78.2 ±0.7 mmHg) than those in the higher quintile (125.3 ±1.1 and 76.9 ±0.7 mmHg, respectively), as well as those participants who consumed regular and low-fat dairy products and of whole grains (for systolic pressure only). The DASH score was inversely and independently associated with hypertension; participants situated in the lower category had nearly fourteen times greater risk than those in the higher category (OR= 14.4; 95%CI: 1.8- 117.9). Conclusions: The adult population of Porto Alegre consumed groups of the DASH diet, but only one fifth presented a DASH-type diet. The present findings confirm the benefits of the DASH diet on blood pressure in a non-intervention setting.

Cryptocurrencies are becoming popular and the demand for monitoring transactions inside them increases alongside with it. In this thesis, I describe few of the most widespread cryptocurrencies built on top of a blockchain and how to obtain information of their transactions in order to raise alarms. I discuss existing solutions and describe application Cryptoalarm designed for monitoring transactions involving specific addresses in order to raise alarms. Cryptoalarm scans blockchains of cryptocurrencies such as Bitcoin, Bitcoin Cash, Litecoin, Zcash, Dash, Ethereum and raises alarms about address activities in real-time.

Předložená dizertační práce se zabývá moderními algoritmy pro kódovaní videosekvencí, zejména algoritmem High Efficiency Video Coding, a jeho použítím v prostředí online streamování. Vzhledem k tomu, že chování koncových diváků směřuje ke sledování video obsahu kdykoli a kdekoli, způsob, jakým je obsah doručen k divákovi, se stává stejně důležitým, jakým je samotné kódování. V této práci se zaměřujeme na užití HEVC ve službách založených na HTTP adaptivním streamování, zejména ve službách využívajích DASH. Dále se zabýváme dalšími aspekty, které mají vliv na kvalitu zážitku (Quality of Experience) tak, jak jej vnímá koncový uživatel. Takovými jsou na příklad přítomnost reklamy či další systémové parametry. Abychom mohli sbírat názory uživatelů, pro naše experimenty často používáme crowdsourcing. Z tohoto důvodu je část této práce věnována samotnému crowdsourcingu a tomu, jak jej lze využít pro hodnocení kvality videa.

Résumé : Ce projet fait partie du projet MFERD (Magnésium Front End Research and Development) qui vise à développer les technologies permettant de rendre les alliages de Magnésium (Mg) comme un principal matériau structural pour les voitures (aujourd'hui essentiellement constituées d'acier quatre fois plus lourd que le Mg) afin d'en réduire leur masse pour des raisons environnementales et sécuritaires. Dans ce travail de maîtrise nous avons regardé la partie acoustique dans le cas d'un tablier (structure métallique derrière le tableau de bord) en magnésium. En effet, le confort acoustique à l'intérieur des voitures est devenu un argument de marketing d'une grande importance. Le tablier en séparant le compartiment moteur, source de bruit, de l'habitacle, joue un rôle important dans l'isolation acoustique de l'intérieur de la voiture. Ainsi le passage d'un tablier en acier à un tablier en Mg ne doit pas entraîner une baisse de performance. Dans ce travail, nous avons d'abord effectué une revue de la littérature sur les types de traitements acoustiques utilisés dans l'industrie automobile ainsi que des différentes techniques de leur modélisation. Nous avons ensuite comparé les performances acoustiques du tablier en Mg sur lequel on a appliqué des traitements classiques (à une couche, deux couches et trois couches) à celles des tabliers en acier et en aluminium et ce, à masse surfacique, raideur et/ou fréquences de résonnances égales. Finalement nous avons optimisé différents concepts de traitements acoustiques innovants appliqués sur le tablier en Mg en vue d'avoir des performances acoustiques semblables ou supérieures à celles du tablier en acier classique. L'optimisation s'est faite à partir d'un modèle SEA (Statitical Energy Analysis) couplé à un code d'optimisation basé sur un algorithme génétique||Abstract : This work is part of the MFERD (Magnesium Front End Research and Development) project which goal is to develop enabling technologies for the use of magnesium alloys as a principal structural material for cars (mainly made in steel which is four time heavier than magnesium) in order to reduce their mass for both, environmental and security concerns. In this work we have focused on the acoustic part, in the case of a magnesium alloy dash panel. The dash board, by separating the engine compartment from the interior cabin, plays a critical role in the insulation of the car interior. Since the acoustic comfort inside the car has become a marketing argument of great importance, the passage from steel to magnesium dash panel should not deteriorate acoustic performances. In this work, we first conducted a literature review on the types of acoustic treatments used in the automotive industry as well as various techniques of their modeling. We then compared the acoustic performances of a Mg dash with attached traditional acoustic treatments (single-layer, two layers and three layers) to those of a steel and aluminum dash panels with the same mass density, stiffness and/or frequency of resonances. Finally, we optimized different concepts of innovative sound packages applied on the Mg dash panel to achieve a noise performance similar or superior to those of a conventional steel dash. The optimization was done using a SEA (Statitical Energy Analysis) model, coupled with an optimization code based on a genetic algorithm.

Cette thèse porte sur l'étude de structures lasers à semi-conducteurs à base d'îlots et de bâtonnets quantiques, connues pour avoir quelques propriétés remarquables telles leur fort gain, leur effet non-linéaire renforcé, leur faible courant de seuil, leur haute température caractéristique ... Les caractérisations en termes de bruit d'intensité et d'injection optique de ces structures montrent un comportement atypique comparativement aux structures classiques (massives ou à base de puits quantiques). Nous avons pu ainsi comparer le bruit d'un laser DFB à bâtonnets quantiques avec celui d'un laser DFB massif ou à puits quantiques. Des études comparatives de bruit ont aussi été effectuées sur des lasers de type Fabry-Perot. Une modélisation du bruit a été confrontée aux résultats expérimentaux et montre l'importance de la prise en compte de la couche de mouillage. L'injection optique, contrairement aux propriétés d'un laser classique, présente un grand nombre de régimes dynamiques fortement non linéaires près du seuil laser (r~1,1) et peu de régimes à seuil modéré (r~3). Ces résultats nous indiquent finalement que le couplage des modes longitudinaux est à la fois fort et fortement amorti par l'interaction avec la couche de mouillage, ce qui nous donne des pistes très intéressantes pour la modélisation du blocage de modes observé dans ces structures. / This thesis focuses on laser diodes made of Quantum Dot/Quantum Dash (QD) structures. These devices have attracted considerable attention due to their remarkable properties, such as high gain, high non-linear effects, low laser-threshold, high thermal stability, etc. Our studies based on RIN (Relative Intensity Noise) and optical injection show unusual behaviour of QD lasers. We have compared the RIN of a QDash DFB laser with a ''classical'' (massif or quantum well) DFB laser as well as for Fabry-Perot type QDot/QDash lasers. Analytical simulations have been faced to experimental results and show the role of the wetting layer. Contrary to what is observed with ''classical lasers'', optical injection exhibits many regimes with strong non-linear dynamics when the laser is biased near the threshold, while there is only a very few regimes at moderate pump. All these results demonstrate a strong coupling with strong dumping between the longitudinal modes through the wetting layer, which is a very interesting point for the understanding of mode-locking in these QDot/QDash structures.

Network Utility Maximization (NUM) provides a key conceptual framework to study reward allocation amongst a collection of users/entities in disciplines as diverse as economics, law and engineering. However when the available resources and/or users' utilities vary over time, reward allocations will tend to vary, which in turn may have a detrimental impact on the users' overall satisfaction or quality of experience. In this thesis, we introduce a generalization of the NUM framework which incorporates the detrimental impact of temporal variability in a user's allocated rewards and explicitly incorporates Mean-Variability-Fairness tradeoffs, i.e., tradeoffs amongst the mean and variability in users' reward allocations, as well as fairness across users. We propose a simple online algorithm to realize these tradeoffs, which, under stationary ergodic assumptions, is shown to be asymptotically optimal, i.e., achieves a long term performance equal to that of an offline algorithm with knowledge of the future variability in the system. This substantially extends work on NUM to an interesting class of relevant problems where users/entities are sensitive to temporal variability in their service or allocated rewards. We extend the theoretical framework and tools developed for realizing Mean-Variability-Fairness tradeoffs to develop a simple online algorithm to solve the problem of optimizing video delivery in networks. The tremendous increase in mobile video traffic projected for the future along with insufficiency of available wireless network capacity makes this one of the most important networking problems today. Specifically, we consider a network supporting video clients streaming stored video, and focus on the problem of jointly optimizing network resource allocation and video clients' video quality adaptation. Our objective is to fairly maximize video clients' video Quality of Experience (QoE) realizing Mean-Variability-Fairness tradeoffs, incorporating client preferences on rebuffering time and the cost of video delivery. We present a simple asymptotically optimal online algorithm NOVA (Network Optimization for Video Adaptation) to solve the problem. Our algorithm uses minimal communication, 'distributes' the tasks of network resource allocation to a centralized network controller, and video clients' video quality adaptation to the respective video clients. Further, the quality adaptation is also optimal for standalone video clients, and is an asynchronous algorithm well suited for use in the Dynamic Adaptive Streaming over HTTP (DASH) framework. We also extend NOVA for use with more general video QoE models, and study NOVA accounting for practical considerations like time varying number of video clients, sharing with other types of traffic, performance under legacy resource allocation policies, videos with variable sized segments etc. / text

The proliferation of new devices (such as smartphones and tablets) promotes new multimedia services (e.g. user-generated live video broadcasting), as well as new streaming techniques (e.g. rate-adaptive streaming). As a matter of fact, scientists observe a formidable, sustainable growth of Internet traffic related to video streaming. Yet, network infrastructures struggle to cope with this growth and it is now frequent that a delivery network is insufficiently provisioned. Such underprovisioning problem is more severe for live videos due to its real-time requirement. In this thesis, we focus on bandwidth efficient video delivery solutions for live streaming in underprovisioned video delivery networks. Specifically, we have two main contributions: (1) a user-generated live videos sharing system based on peer-to-peer (P2P) technique, and (2) a live rate-adaptive streaming system based on Content Delivery Network (CDN). First of all, we built an multioverlay P2P video sharing system which allows Internet users to broadcast their own live videos. Typically, such a system consists of multiple P2P live video streaming systems, and faces the problem of finding a suitable allocation of peer upload bandwidth. We designed various bandwidth allocation algorithms for this problem and showed how optimal solutions can be efficiently computed. Then, we studied the problem of delivering live rate-adaptive streams in the CDN. We identified a discretize streaming model for multiple live videos in modern CDNs. We formulated a general optimization problem through Integer Linear Programming (ILP) and showed that it is NP-complete. Further, we presented a fast, easy to implement, and near-optimal algorithm with approved approximation ratios for a specific scenario. This work is the first step towards streaming multiple live rate-adaptive videos in CDN and provides a fundamental theoretical basis for deeper investigation. Last, we further extended the discretized streaming model into an user-centric one which maximizes the overall satisfaction of an user population. Further, we presented a practical system, which efficiently utilizes CDN infrastructure to deliver live video streams to viewers in dynamic and large-scale CDNs. The benefits of our approaches on reducing the CDN infrastructure capacity is validated through a set of realistic trace-driven large-scale simulations. All in one, this thesis explores bandwidth efficient live video delivery solutions in underprovisioned delivery network for multiple streaming technologies. The aim is to maximally utilize the bandwidth of relay nodes (peers in P2P and forwarding equipments in CDN) to achieve an optimization goal.

There is an increasing demand for multimedia services in heterogeneous wireless networks. Considering the highly dynamic wireless channels and the relatively large size of the multimedia data, how to support efficient and reliable multimedia delivery is a pressing issue. In this dissertation, we investigate the multimedia delivery algorithms in heterogeneous wireless networks from three different aspects. First, we study the single-flow rate adaptation of video streaming algorithm over multiple wireless interfaces. In order to maintain high video streaming quality while reducing the wireless service cost, the optimal video streaming process with multiple links is formulated as a Markov Decision Process (MDP). The reward function is designed to consider the quality of service (QoS) requirements for video traffic, such as the startup latency, playback fluency, average playback quality, playback smoothness and wireless service cost. To solve the MDP in real time, we propose an adaptive, best-action search algorithm to obtain a sub-optimal solution. To evaluate the performance of the proposed adaptation algorithm, we implemented a testbed using the Android mobile phone and the Scalable Video Coding (SVC) codec and conducted experiments with real video flow. Then, with the multiple multimedia flows competing for limited wireless resources, we propose a utility-based scheduling algorithm for multimedia transmission in Drive-thru Internet. A utility model is devised to map the throughput to user's satisfaction level in terms of multimedia data quality, such as Peak Signal-to-Noise Ratio (PSNR) of video. The objective of the scheduling problem is to maximize the total utility. Then the optimization problem is formulated as a finite-state decision problem with the assumption that future arrival information is known, and it is solved by a searching algorithm as the benchmark. To obtain a real-time solution, a practical heuristic algorithm based on the concept of utility potential is devised. We further implemented the solution and conducted extensive simulations using NS-3. Finally, the multimedia dissemination problem in large-scale VANETs is investigated. We first utilize a hybrid-network framework to address the mobility and scalability issues in large-scale VANETs content distribution. Then, we formulate a utility-based maximization problem to find the best delivery strategy and select an optimal path for the multimedia data dissemination, where the utility function has taken the delivery delay, the Quality of Services (QoS) and the storage cost into consideration. We obtain the closed-form of the utility function, and then obtain the optimal solution of the problem with the convex optimization theory. Finally, we conducted extensive trace-driven simulations to evaluate the performance of the proposed algorithm with real traces collected by taxis in Shanghai. In summary, the research outcomes of the dissertation can contribute to three different aspects of multimedia delivery in heterogeneous wireless networks. First, we have proposed a real-time rate adaptation algorithm for video streaming with multiple wireless interfaces, to maintain the high quality while reducing the wireless services cost. Second, we have presented an optimal scheduling algorithm which can maximize the total satisfaction for multimedia transmission in Drive-thru Internet. Third, we have derived the theoretical analysis of the utility functions including delivery delay, QoS and the storage cost, and have obtained an optimal solution for multimedia data dissemination in large-scale VANETs to achieve the highest utility. / Graduate / 0984 / 0544