24 resultados para RRC


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The increased demand for using the Industrial, Scientific and Medical (ISM) unlicensed frequency spectrum has caused interference problems and lack of resource availability for wireless networks. Cognitive radio (CR) have emerged as an alternative to reduce interference and intelligently use the spectrum. Several protocols were proposed aiming to mitigate these problems, but most have not been implemented in real devices. This work presents an architecture for Intelligent Sensing for Cognitive Radios (ISCRa), and a spectrum decision model (SDM) based on Artificial Neural Networks (ANN), which uses as input a database with local spectrum behavior and a database with primary users information. For comparison, a spectrum decision model based on AHP, which employs advanced techniques in its spectrum decision method was implemented. Another spectrum decision model that considers only a physical parameter for channel classification was also implemented. Spectrum decision models evaluated, as well as ISCRa's architecture were developed in GNU-Radio framework and implemented on real nodes. Evaluation of SDMs considered metrics of: delivery rate, latency (Round Trip Time - RTT) and handoff. Experiments on real nodes showed that ISCRa architecture with ANN based SDM increased packet delivery rate and presented fewer frequency variation (handoff) while maintaining latency. Considering higher bandwidth as application's Quality of Service requirement, ANN-SDM obtained the best results when compared to other SDM for cognitive radio networks (CRN).

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Aims: The goal of the current study was to evaluate the impact of maternal sodium intake during gestation on the systemic and renal renin-angiotensin-aldosterone-system (RAAS) of the adult offspring. Main methods: Female Wistar rats were fed high- (HSD-8.0% NaCl) or normal-sodium diets (NSD-1.3% NaCl) from 8 weeks of age until the delivery of their first litter. After birth, the offspring received NSD. Tail-cuff blood pressure (TcBP) was measured in the offspring between 6 and 12 weeks of age. At 12 weeks of age, the offspring were subjected to either one week of HSD or low sodium diet (LSD-0.1 6%NaCl) feeding to evaluate RAAS responsiveness or to acute saline overload to examine sodium excretory function. Plasma (PRA) and renal renin content (RRC), serum aldosterone (ALDO) levels, and renal cortical and medullary renin mRNA expression levels were evaluated at the end of the study. Key findings: TcBP was higher among dams fed HSD, but no TcBP differences were observed among the offspring. Male offspring, however, exhibited increased TcBP after one week of HSD feeding, and this effect was independent of maternal diet. Increased RAAS responsiveness to the HSD and LSD was also observed in male offspring. The baseline levels of PRA. ALDO, and cortical and medullary renin gene expression were lower but the RRC levels were higher among HSD-fed male offspring (HSDoff). Conversely, female HSDoff showed reduced sodium excretion 4 h after saline overload compared with female NSDoff. Significance: High maternal sodium intake is associated with gender-specific changes in RAAS responsiveness among adult offspring. (C) 2012 Elsevier Inc. All rights reserved.

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Researchers suggest that personalization on the Semantic Web adds up to a Web 3.0 eventually. In this Web, personalized agents process and thus generate the biggest share of information rather than humans. In the sense of emergent semantics, which supplements traditional formal semantics of the Semantic Web, this is well conceivable. An emergent Semantic Web underlying fuzzy grassroots ontology can be accomplished through inducing knowledge from users' common parlance in mutual Web 2.0 interactions [1]. These ontologies can also be matched against existing Semantic Web ontologies, to create comprehensive top-level ontologies. On the Web, if augmented with information in the form of restrictions andassociated reliability (Z-numbers) [2], this collection of fuzzy ontologies constitutes an important basis for an implementation of Zadeh's restriction-centered theory of reasoning and computation (RRC) [3]. By considering real world's fuzziness, RRC differs from traditional approaches because it can handle restrictions described in natural language. A restriction is an answer to a question of the value of a variable such as the duration of an appointment. In addition to mathematically well-defined answers, RRC can likewise deal with unprecisiated answers as "about one hour." Inspired by mental functions, it constitutes an important basis to leverage present-day Web efforts to a natural Web 3.0. Based on natural language information, RRC may be accomplished with Z-number calculation to achieve a personalized Web reasoning and computation. Finally, through Web agents' understanding of natural language, they can react to humans more intuitively and thus generate and process information.

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Infrastructure development means for the making of living environment, transport and communications, disaster prevention and national land conservation, agriculture, forestry and fisheries, and energy production and supply. Transport infrastructure development in Cambodia involved with (1) road, (2) railway, (3) port, inland-water way and (4) aviation. All model of transport infrastructure have special different kinds of importance. Railway is different from other base important of railways are transport passengers and traffic freight especially transport for heavy goods in huge capacity and in long distance by safer and faster. Transport in Cambodia for traffic freight export import base from Thailand and other via Sisophon and Shihanoukvill port. Traffic is increasing rapidly during nowadays railway condition in adequate of demand required. This is why Railway is selected as the topic of this paper to prevent monopoly of road transport. This paper, does review about infrastructure development plan for Railway in Cambodia as a long term strategy by review and analysis forecast on the previous performance of Royal Railways of Cambodia (RRC) transport traffic involved with condition of infrastructure development of railway in Cambodia. And also review the plan of development RRC but just only detail a plan of rehabilitation that is immediately needed. Suggest some recommendation at the last part. As Cambodia is a member country of ASEAN and also Mekong sub-region. For make sure that transport networks work effectively with a progress of economic integration, we make clear what is important for infrastructure development of railway in Cambodia from the standpoint of the development plan of Mekong sub-region. This paper is organized by 4 sections. Section 1 review about Infrastructure Development of Railway in Cambodia (IDRC) Historical Background, Follow by Section 2 will review the Current Situation of IDRC and some analysis of transport performance from previous years, Then Section 3 review of the focusing on traffic transport of RRC in the future, Section 4 review Infrastructure Development of Railway in Cambodia Future plans in long term; at last conclusion and recommendation. In section 1 does review history background of RRC from the rail first begun. But why is needed to review? Because of history background is involved infrastructure development of RRC in present time. History background made big gaps constraint and obstacle for socioeconomic development and poverty reduction, also left Cambodia with tragedy and left developed behind. After that remain infrastructure development needs huge fund and long time for restoration, reconstruction, rehabilitation and development into new technology as most of world practice.

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Introdução: Ao longo da última década a procura por um sorriso estético (inclui harmonia e continuidade de forma) transformou-se numa preocupação relevante na Medicina Dentária e em particular nos tratamentos periodontais. As recessões gengivais com as consequentes exposições radiculares e alteração morfológica dos tecidos periodontais, podem constituir um problema estético importante podendo trazer outros problemas associados. Objetivo: O objetivo deste trabalho é identificar qual a técnica cirúrgica mais vantajosa para recobrimento radicular (RRC, RRC com ETC e TUN) e saber em que situações uma poderá ser melhor escolha que a outra, sabendo que ambas são técnicas de alta fiabilidade. Materiais e métodos: Para o cumprimento do objetivo, foi desenvolvida uma pesquisa entre Junho e Setembro de 2016, de artigos em português e inglês, sem limites temporais, recorrendo às bases de dados electrónicas: PUBMED e Google Académico utilizando para o efeito as seguintes “palavras-chave”: “tunnel technique”, “microsurgery”, “recession coverage”, “connective tissue graft”, “coronally advanced flap”, “coronally advanced flap vs. tunnel technique”. Foram utilizados 40 artigos científicos e duas obras literárias (Clinical Periodontology and Implant Dentistry e Plastic-Esthetic Periodontal and Implant Surgery) para complementar o tema. Conclusão: Segundo a literatura publicada e consultada, os procedimentos mais eficazes são aqueles que utilizam enxertos de tecido conjuntivo para o aumento da espessura gengival. Sendo que comparando as duas técnicas Retalho de Reposicionamento Coronal e Técnica de Tunelização, a segunda leva vantagem em relação à primeira, uma vez que, necessitando de menos incisões trará aspetos positivos quanto à cicatrização pois permite maior aporte sanguíneo, além de haver uma preservar das papilas.

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Se basant sur les données d’un large registre américain, le National Health and Nutrition Examination Survey (NHANES) des années 2005-2006, nous avons réalisé une étude transversale où 3406 hommes et femmes âgés entre 20 et 69 ans ont été retenus. L’objectif était d’évaluer l’association entre l’arthrite et les maladies cardiovasculaires (MCV) ainsi que les effets du sexe et de la vitamine D sur cette association. L’arthrite et les maladies cardiovasculaires étaient rapportées dans un questionnaire médical, et l’exposition à la vitamine D était mesurée à partir des concentrations sériques de la 25-hydroxyvitamine D (25(OH)D). Des ajustements pour diverses variables confondantes ont été considérés dans les modèles multivariés. Les analyses statistiques ont été stratifiées par niveau sérique de vitamine D (déficient et suffisant) et appliquées séparément chez les hommes et les femmes. La régression logistique multiple a été utilisée pour évaluer l’association entre l’arthrite et les MCV ; des rapports de cotes (RC) avec leurs intervalles de confiance à 95% ont été calculés. Le modèle complet comprenait un terme d’interaction triple entre l’arthrite, le sexe et la vitamine D, et ce, dans le but d’étudier les possibles effets modifiants du sexe et des concentrations sériques de vitamine D sur l’association entre l’arthrite et les MCV. Pour mesurer ces effets, nous avons calculé des rapports des RC (RRC) avec leurs intervalles de confiance à 95% ; un RRC de 1 signifiant une absence d’effet modifiant. Nous avons observé une double association statistiquement significative entre le diagnostic auto-déclaré de l’arthrite et celui des MCV, mais cette association n’a pas été différente en fonction des concentrations sériques de vitamine D, ni en fonction du sexe.