This work was focused on the study of variability DGAT1 gene in the pig population Czech Large White breed. Subsequently, association analysis was performed of the gene and the different production indicators of quality of pork meat. Examined polymorphism was found at position 103 of intron 2 of chromosome 4. DGAT1 gene has a major role in the synthesis tryacylglycerols and may affect the storage of fat in the body. Relative genotype frequencies were: AA = 0.4222; AG = 0.4889; GG = 0.0889. The values of the relative frequencies of alleles were as follows: A = 0.6666 and G = 0.3334. The association analysis didn't show any statistically significant differences.

Submitted by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2018-10-17T15:06:34Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertação Driely - PPGCAN - Versão Final-merged.pdf: 1694215 bytes, checksum: bb5042043a07c9b564234a5d39c6d5d9 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2018-10-17T15:06:45Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertação Driely - PPGCAN - Versão Final-merged.pdf: 1694215 bytes, checksum: bb5042043a07c9b564234a5d39c6d5d9 (MD5) / Made available in DSpace on 2018-10-17T15:06:46Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertação Driely - PPGCAN - Versão Final-merged.pdf: 1694215 bytes, checksum: bb5042043a07c9b564234a5d39c6d5d9 (MD5) Previous issue date: 2018-07-31 / FAPEAM - Fundação de Amparo à Pesquisa do Estado do Amazonas / Closed aquaculture systems can be enriched with probiotics such as Bacillus subtilis to promote a sustainable fish farming. In this study, we focused on the effect of B. subtilis on a clear water static system compared with a system based biofloc technology (BFT). Tambaqui juveniles were assigned to one of the four treatments, each of which was replicated five times: clear water static system with (CW+BS) or without (CW) B. subtilis, and BFT with (BFT+BS) or without (BFT) B. subtilis. Each replicate group comprised 20 tambaqui juveniles in an artificially aerated 200-L tank. For B. subtilis treatments, tanks were inoculated at weekly intervals with a 4 × 108 cell mL-1culture suspension. All fish were fed (2% of the estimated biomass) three times a day for 62 days. All water parameters of the BFT were within the recommended limits for tambaqui farming. Although there was no interaction between the factors for zootechnical performance, fish raised in the BFT system were 50% heavier than those in the CW system, which was attributable to biofloc consumption. Despite theinoculation with B. subtilis did not improve tambaqui growth, BFT is a promising technology that can be used to save water, decrease aquaculture effluents, and promote tambaqui farming. / Sistemas aquícolas fechados podem ser enriquecidos com probióticos, como o Bacillus subtilis, para promover uma piscicultura sustentável. Neste estudo, foi avaliado o efeito de B. subtilis em um sistema estático com água clara em comparação com um sistema com tecnologia de bioflocos (BFT). Juvenis de tambaqui foram distribuídos em um dos quatro tratamentos, cada um foi replicado cinco vezes: sistema estático de água clara com (AC + BS) ou sem (AC) B. subtilis, e BFT com (BFT + BS) ou sem (BFT) B. subtilis. Cada unidade experimental foi constituída de um tanque de 200 L com 20 juvenis de tambaqui. Para os tratamentos com B. subtilis, os tanques foram inoculados em intervalos semanais com uma suspensão de 4 × 108 células mL-1 de cultura. Todos os peixes foram alimentados (2% da biomassa) três vezes ao dia por 62 dias. Todos os parâmetros da água do BFT estavam dentro dos limites recomendados para a produção de tambaqui. Embora não tenha havido interação entre os fatores para o desempenho zootécnico, peixes criados no sistema BFT foram 50% mais pesados que aqueles no sistema AC, o que foi atribuído ao consumo de bioflocos. Apesar da inoculação com B. subtilis não melhoraro crescimento do tambaqui, o BFT é uma tecnologia promissora que pode ser usada para economizar água, diminuir os efluentes da aqüicultura e promover a produção de tambaqui.

No description available.

La Tolérance aux pannes Byzantines (BFT) est de plus en plus cruciale avec l'évolution d'applications et en raison de la croissance de l'innovation technologique en informatique. Bien que des dizaines de protocoles BFT aient été introduites dans les années précédentes, leur mise en œuvre ne semble pas satisfaisant. Pour faire face à cette complexité, due à la dépendance d'un protocole d'une situation, nous tentons une approche qui permettra de sélectionner un protocole en fonction d'une situation. Ceci nous paraît, en s'inspirant de tout système d'encrage, comme une démarche nécessaire pour aborder la problématique de la BFT. Dans cette thèse, nous introduisons un modèle de sélection ainsi que l'algorithme qui permet de simplifier et d'automatiser le processus d'élection d'un protocole. Ce mécanisme est conçu pour fonctionner selon 3 modes : statique, dynamique et heuristique. Les deux derniers modes, nécessitent l'introduction d'un système réactif, nous ont conduits à présenter un nouveau modèle BFT: Adapt. Il réagit à tout changement et effectue, d'une manière adaptée, la commutation entre les protocoles d'une façon dynamique. Le mode statique permet aux utilisateurs de BFT de choisir un protocole BFT en une seule fois. Ceci est très utile dans les services Web et les " Clouds " où le BFT peut être fournit comme un service inclut dans le contrat (SLA). Ce mode est essentiellement conçu pour les systèmes qui n'ont pas trop d'états fluctuants. Pour ce faire, un processus d'évaluation est en charge de faire correspondre, à priori, les préférences de l'utilisateur aux profils du protocole BFT nommé, en fonction des critères de fiabilité et de performance. Le protocole choisi est celui qui réalise le meilleur score d'évaluation. Le mécanisme est bien automatisé à travers des matrices mathématiques, et produit des sélections qui sont raisonnables. D'autres systèmes peuvent cependant avoir des conditions flottantes, il s'agit de la variation des charges ou de la taille de message qui n'est pas fixe. Dans ce cas, le mode statique ne peut continuer à être efficace et risque de ne pas pouvoir s'adapter aux nouvelles conditions. D'où la nécessité de trouver un moyen permettant de répondre aux nouvelles exigences d'une façon dynamique. Adapt combine un ensemble de protocoles BFT ainsi que leurs mécanismes de commutation pour assurer l'adaptation à l'évolution de l'état du système. Par conséquent, le "Meilleur" protocole est toujours sélectionné selon l'état du système. On obtient ainsi une qualité optimisée de service, i.e., la fiabilité et la performance. Adapt contrôle l'état du système grâce à ses mécanismes d'événements, et utilise une méthode de "Support Vector Regrssion" pour conduire aux prédictions en temps réel pour l'exécution des protocoles (par exemple, débit, latence, etc.). Ceci nous conduit aussi à un mode heuristique. En utilisant des heuristiques prédéfinies, on optimise les préférences de l'utilisateur afin d'améliorer le processus de sélection. L'évaluation de notre approche montre que le choix du "meilleur" protocole est automatisé et proche de la réalité de la même façon que dans le mode statique. En mode dynamique, Adapt permet toujours d'obtenir la performance optimale des protocoles disponibles. L'évaluation démontre, en plus, que la performance globale du système peut être améliorée de manière significative. Explorer d'autres cas qui ne conduisent pas de basculer entre les protocoles. Ceci est rendu possible grâce à la réalisation des prévisions d'une grande précision qui peuvent atteindre plus de 98%dans de nombreux cas. La thèse montre que cette adaptabilité est rendue possible grâce à l'utilisation des heuristiques dans un mode dynamique.

<p dir="ltr">Practically, Byzantine faults are not assumed in cloud applications. Byzantine fault-tolerance adds significant cryptographic, communication, throughput, and latency overheads to applications, contributing to the resistance towards its widespread adoption. Existing Byzantine-fault tolerant protocols focus on optimal latency or optimal communication while ignoring the throughput and cryptographic overheads.</p><p dir="ltr">In this thesis, we explore pipelining for Byzantine fault-tolerant applications. Pipelining tasks is a common optimization in distributed systems that involves executing tasks in stages. The idea is that instead of executing a task in an iteration as an atomic unit, we split the execution into stages and execute all stages of <i>different</i> tasks per iteration. We observe significant performance benefits if executing later stages of a task helps other tasks in earlier stages, saving effort in each stage. The length of the pipeline, i.e., the number of stages, determines the latency of an individual task. However, if the pipeline improves the execution of every stage enough, then the latency improves.</p><p dir="ltr">We primarily explore three Byzantine Fault Tolerant (BFT) applications with pipelining: (i) unique chain-based State Machine Replication protocols: <i>Apollo</i>, <i>Artemis</i>, <i>Leto</i>, and <i>Zeus</i>, and (ii) energy-efficient State Machine Replication: <i>EESMR</i>. (iii) random beacon protocols: <i>GRandPiper</i>, <i>BRandPiper</i>, and <i>OptRand</i>. We design them with a pipeline-first approach to improve the throughput, cryptographic, and communication costs at every stage of the pipeline. With respect to latency, we show (i) pipelined SMR protocols where our pipeline stages have constant cryptographic and linear communication costs allowing our protocols to outperform state-of-the-art BFT-SMR protocols in throughput. (ii) pipelined SMR protocols with techniques to make each stage of the pipeline independent, thus achieving demonstrable energy efficiency while allowing an unbounded number of non-interactive parallel proposals. (iii) reduced latencies for reconfiguration-friendly random beacons by using two pipelines: an SMR pipeline to commit and a beacon pipeline to produce random numbers and decoupling the two pipelines thereby removing the impact of the high-latency SMR pipeline on the latency of the randomness output by the system. </p>

Submitted by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2016-11-29T14:58:13Z No. of bitstreams: 1 Dissertação - Rayol de Mendonça Neto.pdf: 7610835 bytes, checksum: 6c4c8ac8cd33ea82c062cd5bb0830639 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2016-11-29T14:58:26Z (GMT) No. of bitstreams: 1 Dissertação - Rayol de Mendonça Neto.pdf: 7610835 bytes, checksum: 6c4c8ac8cd33ea82c062cd5bb0830639 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2016-11-29T14:58:46Z (GMT) No. of bitstreams: 1 Dissertação - Rayol de Mendonça Neto.pdf: 7610835 bytes, checksum: 6c4c8ac8cd33ea82c062cd5bb0830639 (MD5) / Made available in DSpace on 2016-11-29T14:58:46Z (GMT). No. of bitstreams: 1 Dissertação - Rayol de Mendonça Neto.pdf: 7610835 bytes, checksum: 6c4c8ac8cd33ea82c062cd5bb0830639 (MD5) Previous issue date: 2016-05-17 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Directory services are often used to store sensitive information (e.g., data and user credentials) in many critical systems such as access control and authentication services, DNS servers, e-mail and public key infrastructures. Although they provide a certain degree of security to prevent attacks and failures (e.g., security protocols and self replication mechanisms), the current directory services implementations, based on LDAP, they are not safe in fact, scalable and intrusions free. In this context, this work presents the first architecture for directory services based on the LDAP protocol, capable to tolerate failures and intrusions. For the development of this architecture is employed state machine replication to tolerate failure, and the diversity of systems at different levels to tolerate intrusions. The feasibility and applicability of the proposed solution is shown through several experiments. As a result, it is possible to attest that the system is efficient, with a performance at least three times better than the state of the art, as well as scalable and resilient. / Serviços de diretório são frequentemente usados para armazenar informações sensíveis (e.g., dados e credenciais de usuários) nos mais variados sistemas críticos, tais como serviços de autenticação e controle de acesso, servidores DNS, e-mail e infra-estrutura de chaves públicas. Embora possuam um certo grau de segurança para evitar ataques e falhas (e.g., protocolos de segurança e mecanismos próprios de replicação de dados), as atuais implementações de serviços de diretórios, baseadas no protocolo LDAP, não são de fato seguras, escaláveis e livres de intrusões. É neste contexto que esta dissertação apresenta a primeira arquitetura para serviços de diretórios, baseado no protocolo LDAP, capaz de tolerar falhas e intrusões. Para o desenvolvimento desta arquitetura é empregada a replicação de máquinas de estado, para tolerar falhas, e a diversidade de sistemas, em diferentes níveis, para tolerar intrusões. A viabilidade e aplicabilidade da solução proposta é demonstrada através de diversos experimentos. Como resultado, é possível atestar que o sistema é eficiente, com um desempenho no mínimo três vezes melhor que o estado da arte, bem como escalável e resiliente.

No description available.

In this dissertation an in-depth study was conducted into the design, implementation and evaluation of a QPSK-based receiver structure for application in a UMTS WCDMA environment. The novelty of this work lies with the specific receiver architecture aimed to optimise the BER performance when possibly sparse data streams are transmitted. This scenario is a real possibility according to Verd´u et al [1] and Hagenauer et al [2–6]. A novel receiver structure was conceptualised, developed and evaluated in both narrowband and wideband scenarios, where it was found to outperform conventional receivers when a sparse data stream is transmitted. In order to reach the main conclusions of this study, it was necessary to develop a realistic simulation platform. The developed platform is capable of simulating a communication system meeting the physical layer requirements of the UMTS WCDMA standard. The platform can also perform narrowband simulations. A flexible channel emulator was developed that may be configured to simulate AWGN channel conditions, frequency non-selective fading (either Rayleigh or Rician with a configurable LOS component and Doppler spread), or a full multipath scenario where each path has a configurable LOS component, Doppler spread, path gain and path delay. It is therefore possible to even simulate a complex, yet realistic, COST207-TU channel model. The platform is also capable of simulating MUI. Each interfering user has a unique and independent multipath fading channel, while sharing the same bandwidth. Finally, the entire platform executes all simulations in baseband for improved simulation times. The research outputs of this work are summarised below: <ul> <li>A parameter, the sparseness measure, was defined in order to quantify the level by which a data stream differs from an equiprobable data stream.</li> <li>A novel source model was proposed and developed to simulate data streams with a specified amount of sparseness.</li> <li>An introductory investigation was undertaken to determine the effect of simple FEC techniques on the sparseness of an encoded data stream.</li> <li>Novel receiver structures for both narrowband and wideband systems were proposed, developed and evaluated for systems where possibly sparse data streams may be transmitted.</li> <li>Analytic expressions were derived to take the effect of sparseness into account in communication systems, including expressions for the joint PDF of a BPSK branch, the optimal decision region of a detector in AWGN conditions as well as the BER performance of a communication system employing the proposed optimal receiver in both AWGN channel conditions as well as in flat fading channel conditions.</li> <li>Numerous BER performance curves were obtained comparing the proposed receiver structure with conventional receivers in a variety of channel conditions, including AWGN, frequency non-selective fading and a multipath COST207-TU channel environment, as well as the effect of MUI</li></ul>. AFRIKAANS : In hierdie verhandeling word ’n in-diepte studie gedoen rakende die ontwerp, implementasie en evaluasie van ’n KPSK-gebaseerde ontvanger struktuur wat in ’n UMTS WKVVT omgewing gebruik kan word. Die bydrae van hierdie werk lˆe in die spesifieke ontvanger argitektuur wat daarop mik om die BFT werksverrigting te optimeer wanneer yl data strome versend word. Hierdie is ’n realistiese moontlikheid volgens Verd´u et al [1] en Hagenauer et al [2–6]. ’n Nuwe ontvanger struktuur is gekonsepsualiseer, ontwikkel en evalueer vir beide noueband en wyeband stelsels, waar dit gevind is dat dit beter werksverrigting lewer as tradisionele ontvangers wanneer yl data strome versend word. Dit was nodig om ’n realistiese simulasie platform te ontwikkel om die belangrikste gevolgtrekkings van hierdie studie te kan maak. Die ontwikkelde platform is in staat om ’n kommunikasie stelsel te simuleer wat aan die fisiese laag vereistes van die UMTS WKVVT standaard voldoen. Die platform kan ook noueband stelsels simuleer. ’n Aanpasbare kanaal simulator is ontwikkel wat opgestel kan word om SWGR kanaal toestande, plat duining (beide Rayleigh of Ricies met ’n verstelbare siglyn komponent en Doppler verspreiding), sowel as ’n veelvuldige pad omgewing (waar elke unieke pad ’n verstelbare siglyn komponent, Doppler verspreiding, pad wins en pad vertraging het) te emuleer. Dit is selfs moontlik om ’n komplekse, maar steeds realistiese COST207-TU kanaal model te simuleer. Die platform het ook die vermo¨e om VGS te simuleer. Elke steurende gebruiker het ’n unieke en onafhanklike veelvuldige pad deinende kanaal, terwyl dieselfde bandwydte gedeel word. Laastens, alle simulasies van die platvorm word in basisband uitgevoer wat verkorte simulasie periodes verseker. Die navorsingsuitsette van hierdie werk kan as volg opgesom word: <ul> <li>’n Parameter, die ylheidsmaatstaf, is gedefin¨ýeer om dit moontlik te maak om die vlak waarmee die ylheid van ’n datastroom verskil van ’n ewekansige stroom te versyfer.</li> <li>’n Nuwe bronmodel is voorgestel en ontwikkel om datastrome met ’n spesifieke ylheid te emuleer.</li> <li>’n Inleidende ondersoek is onderneem om vas te stel wat die effek van VFK tegnieke op die ylheid van ’n enkodeerde datastroom is.</li> <li>Nuwe ontvanger strukture is voorgestel, ontwikkel en evalueer vir beide noueband en wyeband stelsels waar yl datastrome moontlik versend kan word.</li> <li>Analitiese uitdrukkings is afgelei om die effek van ylheid in ag te neem in kommunikasie stelsels. Uitdrukkings vir onder andere die gedeelte WDF van ’n BFVK tak, die optimale beslissingspunt van ’n detektor in SWGR toestande, sowel as die BFT werksverrigting van ’n kommunikasie stelsel wat van die voorgestelde optimale ontvangers gebruik maak, hetsy in SWGR of in plat duinende kanaal toestande.</li> <li>Talryke BFT werksverrigting krommes is verkry wat die voorgestelde ontvanger struktuur vergelyk met die konvensionele ontvangers in ’n verskeidenheid kanaal toestande, insluitend SWGR, plat duinende kanale en ’n veelvuldige pad COST207-TU kanaal omgewing, sowel as in die teenwoordigheid van VGS.</li></ul></p Copyright / Dissertation (MEng)--University of Pretoria, 2010. / Electrical, Electronic and Computer Engineering / unrestricted