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Diretrizes para desenvolvimento de projeto para ligações de painéis de fachada horizontais de concreto pré-moldado
(Universidade Federal de São Carlos, 2009-03-03) Uehara, Fábio Nori; Ferreira, Marcelo de Araújo; https://lattes.cnpq.br/4199122391532470; https://lattes.cnpq.br/6914894161460683
The increasing of using precast concrete panels, lack of standardization, lack of studies on precast concrete panels and its connections devices on Brazil, has led to the need of manual and design criteria of precast concrete panel connections. Although the designers and precast concrete panel manufacturers is using foreign standards when its available and their empirical knowledge on the specification and connections design criteria, the lack of manuals become hard to find solutions that provide easiness of precast concrete panel s employment. Connections are fundamental part of the precast structures. For the building assembly are necessary linking devices which influences the production process, the efficiency of casting, storage, transport, handling and especially in the assembly on site. This work presents the concept, technical features and functions of main types of spandrel panel connections and the main structure of building, and identifies typical connections and the general design recommendation. This report purpose the put in connection as a new classification of connection type.
Ação afirmativa e raça no Brasil: uma análise de enquadramento midiático do debate político contemporâneo sobre a redefinição simbólica da nação
(Universidade Federal de São Carlos, 2009-03-03) Moya, Thais Santos; Silvério, Valter Roberto; https://lattes.cnpq.br/2139497152210336
Regiões de incerteza para a curva ROC em testes diagnósticos
(Universidade Federal de São Carlos, 2009-03-03) Vaz, Janaina Cândida Lopes; Milan, Luis Aparecido; https://lattes.cnpq.br/9208866703878468
Diagnostic tests are methods capable of indicating the presence or absence of a disease, with a probability of error. The performance of a diagnostic test can be verified by some indicator, as: the specificity, the sensitivity and the ROC curve. A graph of the specificity complement versus sensitivity is called as ROC curve. The ROC curve demonstrates the test s ability to discriminate the different disease diagnosis, therefore it is a graphical tool that is used to assess the performance of a test. We define three types of confidence regions around the ROC curve: the punctual, the regional and the global. In some instances, depending on the clinical needs, the decision is taken under an specific region of the ROC curve. We review some procedures for estimating confidence region for the ROC curve and we propose two new methods (optimized averages and averages thresholds optimized) to estimating that region. We use the bootstrap method to search for a confidence region around the ROC curve. Using numerical examples, we apply the methods an compare their performance.
Sílica coloidal como agente ligante e fonte mulitizadora em concretos refratários
(Universidade Federal de São Carlos, 2009-03-03) Magliano, Marcus Vinicius Morais; Pandolfelli, Victor Carlos; https://lattes.cnpq.br/7369376873984839; https://lattes.cnpq.br/9573935053660526
The recent development of refractory castables for high temperatures applications are closely related to binders technology, especially those presenting superior performance and installation properties. The calcium aluminate cement (CAC), one of the most used binder for refractories, has passed over the last years through several enhancements leading to an increase of monolithic use instead of traditional bricks. The continuous search for new binder s came to the development of several binding systems such as hidratable alumina, and others. Nowadays, with the strong presence of nanotechnology on all science fields, new binders containing nano structures are being studied. The colloidal silica is one of the most studied nano structured binder. It has three mains advantages, that places it as a promising substitute for CAC in some applications. First it contains nano pores that facilitates the drying process. Second, it does not have hydraulics components, avoiding reduction on mechanical strength at intermediate temperatures. Third, it is free of CaO and others elements that could deteriorate the performance at high temperatures. Furthermore, the colloidal silica is a highly reactive source of SiO2. This work aims to study the influence of hidratable alumina, CAC and colloidal silica for mullitization on alumina based compositions. The objective is to compare green and final properties as well as the amount and morphology of the mullite formed. The results indicated better drying conditions, superior high temperatures properties and suggested higher mullitization for castables using colloidal silica. However, the molding and curing steps should be well controlled to avoid cracks due to high reactiveness of this binder.