Betões especiais: aplicações em edifícios

Atualmente o betão é o material estrutural mais utilizado a nível mundial no âmbito da construção civil. É composto por água, agregados grossos e finos, com ou sem adjuvantes, cimento e adições. Atendendo ao facto de a sua utilização ter vindo a ser bastante significativa, ao mesmo tempo torna-se uma solução dispendiosa, dada a presença de alguns dos seus constituintes, principalmente o cimento Portland. O aparecimento de novos componentes, capazes de substituírem parte do cimento e de aumentarem as capacidades do betão para responder às expectativas, nomeadamente, as adições e adjuvantes, induziram ao surgimento de betões mais resistentes, duradouros e capazes de responderem melhor às condições que lhes são exigidas em projeto. Neste contexto, desenvolveu-se o presente trabalho, com o objetivo de estudar as soluções em betão com maior viabilidade económica. Ao longo do presente estudo, pretende-se avaliar a possibilidade de recorrer à utilização de betões especiais para a construção de alguns elementos estruturais de edifícios. Nesta perspetiva, numa fase inicial do trabalho, apresenta-se uma breve introdução histórica sobre a evolução do betão, desde a sua descoberta até à atualidade, e, em seguida, discutem-se as vantagens e as desvantagens referentes a cada betão quando aplicado em diferentes elementos estruturais. Posteriormente, é feita uma breve análise, comparação e discussão de resultados referentes aos custos atualmente praticados em Portugal Continental e na Ilha da Madeira relativos a cada tipo de betão. A dissertação termina com a análise dos resultados obtidos.

Vermiculitas tratadas quimicamente na obtenção de sólidos microporosos como precursores para híbridos inorgânico-orgânicos com aplicações adsortivas

ALVES, Ana paula Melo. Vermiculitas tratadas quimicamente na obtenção de sólidos microporosos como precursores para híbridos inorgânico-orgânicos com aplicações adsortivas. 2009. 124 f. Tese (Doutorado em Quimica) - Centro de Ciências Exatas e da Natureza, Universidade Federal da Paraíba, João Pessoa, PB, 2009.

Nitretação a plasma: fundamentos e aplicações

A nitretação é uma técnica de tratamento de superfície utilizada para endurecer superfícies de metais, principalmente de aços. O uso do plasma para auxiliar esta técnica vem crescendo nos últimos anos. Pelo fato desta técnica utilizar o plasma como fonte energética e este possuir uma vasta aplicação em outras técnicas para processamento de materiais, enobrece ainda mais a leitura do presente livro. Ele apresenta uma revisão da descarga elétrica em gases levando o leitor a refletir, multidisciplinarmente, sobre possibilidades de aplicação da mesma. Apresenta a técnica de nitretação iônica sob o aspecto histórico, científico, tecnológico, operacional e econômico e, finalmente, faz uma revisão das novas técnicas de endurecimento superficial assim como as técnicas convencionais de nitretação

Construção das capacidades organizacionais de tecnologia da informação no contexto dos sistemas institucionais integrados de gestão da UFRN

The IT capability is a organizational ability to perform activities of this role more effectively and an important mechanism in creating value. Its building process (stages of creation and development) occurs through management initiatives for improvement in the performance of their activities, using human resources and IT assets complementary responsible for the evolution of their organizational routines. This research deals with the IT capabilities related to SIG (integrated institutional management systems), built and deployed in UFRN (Universidade Federal do Rio Grande do Norte) to realization and control of administrative, academic and human resources activities. Since 2009, through cooperative agreements with federal and educational institutions of direct administration, UFRN has supported the implementation of these systems, currently involving more than 30 institutions. The present study aims to understand how IT capabilities, relevant in the design, implementation and dissemination of SIG, were built over time. This is a single case study of qualitative and longitudinal nature, performed by capturing, coding and analysis from secondary data and from semi-structured interviews conducted primarily with members of Superintenência de Informática, organizational unit responsible for SIG systems in UFRN. As a result, the technical, of internal relationship and external cooperation capabilities were identified as relevant in the successful trajectory of SIG systems, which have evolved in different ways. The technical capacity, initiated in 2004, toured the stages of creation and development until it reached the stage of stability in 2013, due to technological limits. Regarding the internal relationship capability, begun in 2006, it toured the stages of creation and development, having extended its scope of activities in 2009, being in development since then. Unlike the standard life cycle observed in the literature, the external cooperation capability was initiated by an intensity of initiatives and developments in the routines in 2009, which were decreasing to cease in 2013 in order to stabilize the technological infrastructure already created for cooperative institutions. It was still identified the start of cooperation in 2009 as an important event selection, responsible for changing or creating trajectories of evolution in all three capacities. The most frequent improvements initiatives were of organizational nature and the internal planning activity has been transformed over the routines of the three capabilities. Important resources and complementary assets have been identified as important for the realization of initiatives, such as human resources technical knowledge to the technical capabilities and external cooperation, and business knowledge, for all of them, as well as IT assets: the iproject application for control of development processes, and the document repository wiki. All these resources and complementary assets grew along the capacities, demonstrating its strategic value to SINFO/UFRN

Responsabilidade social: visões e perspectivas de empresários do segmento industrial do Rio Grande do Norte

The theme Corporate Social Responsibility is relatively recent both in the academic field and in the business practice. Because of the lack of socialization of experiences and precision of concepts, there are gaps regarding the understanding of the subject and, also, how to conduct operations. This study just seeks to investigate such matter, focusing applications of social responsibility in business. It takes, as empirical field, winners of the PSQT - SESI Prize of Quality at Work in Rio Grande do Norte (2002-2007) in order to systematize the various approaches on the issue, aiming to reveal subjective visions and perspectives of the theme. It is characterized as a qualitative study, carried out by structured interview. The universe was composed by 15 companies. It was used analysis of content categorical as an axis for the interpretation of the information. Three approaches guided the analysis: Business Ethics, (normative); Business & Society (contractual); Social Issues Management (strategic). The findings are related in three ways: 1) reasons for the CSR practice; 2) the results obtained; 3) the means of CSR. It was found that the award participation occurs, mostly, linked to SESI invitations, so, as an articulated movement of industrial corporations in Brazil it occurs, also, because of the organizational commitment with the society and the possibility of internal and social growths and because of the importance attributed to the report as an instrument of consultancy. There are no indicators to check impacts of organizational interventions, in spite of the existence of planning for the actions. Social responsibility appears as a tool to reinforce the organizational image and to increase satisfaction of the employees. There is a tendency of large and medium firms to a contractual commitment while the small and the micros firms are on strategic or normative level. The analysis of the perspectives of social responsibility future revealed trends towards for strategic approach

A gestão da informação sob a luz do Enterprise Content Management (ECM): um estudo de caso em uma universidade pública

This work involves the organization and content perspectives on Enterprise Content Management (ECM) framework. The case study at the Federal University of Rio Grande do Norte was based on ECM model to analyse the information management provided by the three main administrative systems: The Integrated Management of Academic Activities (SIGAA), Integrated System of Inheritance, and Contracts Administration (SIPAC) and the Integrated System for Administration and Human Resources (SIGRH). A case study protocol was designed to provide greater reliability to research process. Four propositions were examined in order to reach the specific objectives of identification and evaluation of ECM components from UFRN perspective. The preliminary phase provided the guidelines for the data collection. In total, 75 individuals were interviewed. Interviews with four managers directly involved on systems design were recorded (average duration of 90 minutes). The 70 remaining individuals were approached in random way in UFRN s units, including teachers, administrative-technical employees and students. The results showed the presence of many ECM elements in the management of UFRN administrative information. The technological component with higher presence was "management of web content / collaboration". But initiatives of other components (e.g. email and document management) were found and are in continuous improvement. The assessment made use of eQual 4.0 to examine the effectiveness of applications under three factors: usability, quality of information and offered service. In general, the quality offered by the systems was very good and walk side by side with the obtained benefits of ECM strategy adoption in the context of the whole institution

Previsão do índice bovespa por meio de redes neurais artificiais: uma análise comparada aos métodos tradicionais de séries de tempo

Forecast is the basis for making strategic, tactical and operational business decisions. In financial economics, several techniques have been used to predict the behavior of assets over the past decades.Thus, there are several methods to assist in the task of time series forecasting, however, conventional modeling techniques such as statistical models and those based on theoretical mathematical models have produced unsatisfactory predictions, increasing the number of studies in more advanced methods of prediction. Among these, the Artificial Neural Networks (ANN) are a relatively new and promising method for predicting business that shows a technique that has caused much interest in the financial environment and has been used successfully in a wide variety of financial modeling systems applications, in many cases proving its superiority over the statistical models ARIMA-GARCH. In this context, this study aimed to examine whether the ANNs are a more appropriate method for predicting the behavior of Indices in Capital Markets than the traditional methods of time series analysis. For this purpose we developed an quantitative study, from financial economic indices, and developed two models of RNA-type feedfoward supervised learning, whose structures consisted of 20 data in the input layer, 90 neurons in one hidden layer and one given as the output layer (Ibovespa). These models used backpropagation, an input activation function based on the tangent sigmoid and a linear output function. Since the aim of analyzing the adherence of the Method of Artificial Neural Networks to carry out predictions of the Ibovespa, we chose to perform this analysis by comparing results between this and Time Series Predictive Model GARCH, developing a GARCH model (1.1).Once applied both methods (ANN and GARCH) we conducted the results' analysis by comparing the results of the forecast with the historical data and by studying the forecast errors by the MSE, RMSE, MAE, Standard Deviation, the Theil's U and forecasting encompassing tests. It was found that the models developed by means of ANNs had lower MSE, RMSE and MAE than the GARCH (1,1) model and Theil U test indicated that the three models have smaller errors than those of a naïve forecast. Although the ANN based on returns have lower precision indicator values than those of ANN based on prices, the forecast encompassing test rejected the hypothesis that this model is better than that, indicating that the ANN models have a similar level of accuracy . It was concluded that for the data series studied the ANN models show a more appropriate Ibovespa forecasting than the traditional models of time series, represented by the GARCH model

Tangibilidade, classe de ativos e estrutura de capital das empresas listadas na BM&FBOVESPA

This study aims to investigate the influence of the asset class and the breakdown of tangibility as determinant factors of the capital structure of companies listed on the BM & FBOVESPA in the period of 2008-2012. Two current assets classes were composed and once they were grouped by liquidity, they were also analyzed by the financial institutions for credit granting: current resources (Cash, Bank and Financial Applications) and operations with duplicates (Stocks and Receivables). The breakdown of the tangible assets was made based on its main components provided as warrantees for loans like Machinery & Equipment and Land & Buildings. For an analysis extension, three metrics for leverage (accounting, financial and market) were applied and the sample was divided into economic sectors, adopted by BM&FBOVESPA. The data model in dynamic panel estimated by a systemic GMM of two levels was used in this study due its strength to problems of endogenous relationship as well as the omitted variables bias. The found results suggest that current resources are determinants of the capital structure possibly because they re characterized as proxies for financial solvency, being its relationship with debt positive. The sectorial analysis confirmed the results for current resources. The tangibility of assets has inverse proportional relationship with the leverage. As it is disintegrated in its main components, the significant and negative influence of machinery & equipment was more marked in the Industrial Goods sector. This result shows that, on average, the most specific assets from operating activities of a company compete for a less use of third party resources. As complementary results, it was observed that the leverage has persistence, which is linked with the static trade-off theory. Specifically for financial leverage, it was observed that the persistence is relevant when it is controlled for the lagged current assets classes variables. The proxy variable for growth opportunities, measured by the Market -to -Book, has the sign of its contradictory coefficient. The company size has a positive relationship with debt, in favor of static trade-off theory. Profitability is the most consistent variable in all the performed estimations, showing strong negative and significant relationship with leverage, as the pecking order theory predicts

Avaliação da política pública de acessibilidade no período de 1992 a 2002 na Cidade do Natal

Este estudio tiene como objetivo evaluar los avances y límites de las políticas de accesibilidad en la ciudad de Natal. Se investigan las políticas publicas municipales de accesibilidad implantadas en los diez años subsecuentes, a partir de la sanción de la Ley Municipal de Accesibilidad Nº 4.090 del 03 de junio de 1992, que torna obligatorio la eliminación de las barreras arquitectónicas para personas con discapacidades en los lugares de circulación de peatones y edificios de uso público de la ciudad. Accesibilidad, en los proyectos de arquitectura y urbanismo es la condición esencial para asegurar a cualquier ciudadano su derecho a ir y venir con seguridad, dignidad y autonomía. Esta investigación se concentra en los barrios de: ciudad alta, Petrópolis y Ribeira, ya que esta área, en el período ya mencionado, fue la que tuvo una mayor concentración del presupuesto de inversiones públicas municipales de la ciudad de Natal, en la eliminación de barreras arquitectónicas en vías urbanas. El método adoptado fue el hipotético deductivo, a partir de la formulación de dos hipótesis de trabajo: la primera, una divergencia entre los objetivos propuestos por la Ley Nº 4.090 y sus aplicaciones prácticas y, la segunda, de las diferencias que existen en el grado de entendimiento del concepto de accesibilidad, para eso, se realizó una colecta y análisis de datos tanto empíricos como teóricos. Este estudio también retrata en el año de 2004, con el uso de la técnica de la fotografía, la realidad actual de la ciudad sirviendo como un parámetro comparativo con los proyectos asociados a la Coordinación para integración de las personas con discapacidades. Se utiliza la técnica de entrevista con especialistas en accesibilidad envueltos a lo largo del proceso de implantación de las políticas públicas en la ciudad de Natal, durante los años mencionados, obteniendo así un testimonio sobre las directrices adoptadas en ese período, con base en la legislación vigente. En la investigación documental y fotográfica se realiza una evaluación de la dimensión real de lo propuesto y ejecutado en un periodo de diez años, y se concluye sobre todos los avances y retrocesos de las políticas de gestiones públicas adoptadas con relación a la accesibilidad en la ciudad de Natal

Do modelo geométrico ao modelo físico: o tridimensional na educação do arquiteto e urbanista

In the teaching practice of architecture and urbanism in Brazil, educational legislation views modeling laboratories and workshops as an indispensable component of the infrastructure required for the good functioning of any architectural course of study. Although the development of information technology at the international level has created new possibilities for digital production of architectural models, research in this field being underway since the early 1990s, it is only from 2007 onwards that such technologies started to be incorporated into the teaching activity of architecture and urbanism in Brazil, through the pioneering experience at LAPAC/FEC/UNICAMP. It is therefore a recent experiment whose challenges can be highlighted through the following examples: (i) The implementation of digital prototyping laboratories in undergraduate courses of architecture and urbanism is still rare in Brazil; (ii) As a new developing field with few references and application to undergraduate programs, it is hard to define methodological procedures suitable for the pedagogical curricula already implemented or which have already been consolidated over the years; (iii) The new digital ways for producing tridimensional models are marked with specificities which make it difficult to fit them within the existing structures of model laboratories and workshops. Considering the above, the present thesis discusses the tridimensional model as a tool which may contribute to the development of students skills in perceiving, understanding and representing tridimensional space. Analysis is made of the relation between different forms of models and the teaching of architectural project, with emphasis on the design process. Starting from the conceptualization of the word model as it is used in architecture and urbanism, an attempt is made to identify types of tridimensional models used in the process of project conception, both through the traditional, manual way of model construction as well as through the digital ones. There is also an explanation on how new technologies for digital production of models through prototyping are being introduced in undergraduate academic programs of architecture and urbanism in Brazil, as well as a review of recent academic publications in this area. Based on the paradigm of reflective practice in teaching as designed by Schön (2000), the experiment applied in the research was undertaken in the integrated workshop courses of architectural project in the undergraduate program of architecture and urbanism at Universidade Federal do Rio Grande do Norte. Along the experiment, physical modeling, geometric modeling and digital prototyping are used in distinct moments of the design process with the purpose of observing the suitability of each model to the project s phases. The procedures used in the experiments are very close to the Action Research methodology in which the main purpose is the production of theoretical knowledge by improving the practice. The process was repeated during three consecutive semesters and reflection on the results which were achieved in each cycle helped enhancing the next one. As a result, a methodological procedure is proposed which consists of the definition of the Tridimensional Model as the integrating element for the contents studied in a specific academic period or semester. The teaching of Architectural Project as it is developed along the fifth academic period of the Architecture and Urbanism undergraduate program of UFRN is taken as a reference

Fachada flexível para casa padronizada em condomínios

The employment of flexibility in the design of façades makes them adaptable to adverse weather conditions, resulting in both minimization of environmental discomfort and improvement of energy efficiency. The present study highlights the potential of flexible façades as a resource to reduce rigidity and form repetition, which are usually employed in condominiums of standardized houses; as such, the work presented herein contributes to field of study of architectural projects strategies for adapting and integrating buildings within the local climate context. Two façade options were designed using as reference the bionics and the kinetics, as well as their applications to architectural constructions. This resulted in two lightweight and dynamic structures, which cater to constraints of comfort through combinations of movements, which control the impact of solar radiation and of cooling in the environment. The efficacy and technical functionality of the façades were tested with comfort analysis and graphic computation software, as well as with physical models. Thus, the current research contributes to the improvement of architectural solutions aimed at using passive energy strategies in order to offer both better quality for the users and for the sustainability of the planet

Atividades biológicas de polissacarídeos sulfatados extraídos da alga vermelha gracilaria caudata

In recent years, sulfated polysaccharides (SP) from marine algae have emerged as an important class of natural biopolymers with potential pharmacology applications. Among these, SP isolated from the cell walls of red algae have been study due to their anticoagulant,antithrombotic and anti-inflammatory activities. In the present study, three sulfated polysaccharides fractions denominated F1.5v, F2.0v and F3.0v were obtained from seaweed G. caudate by proteolysis followed to acetone fractionation. Gel electrophoresis using 0.05 M 1,3-diaminopropane-acetate buffer, pH 9,0, stained with 0.1% toluidine blue, showed the presence of SP in all fractions. The chemical analysis demonstrated that all the fractions are composed mainly of galactose. These compounds were evaluated in anticoagulant, antioxidant and antiproliferative activities. In anticoagulant activity evaluated through aPTT and PT tests, no one fractions presented anticoagulant activity at tested concentrations (0.1 mg/mL; 1.0 mg/mL; 2.0 mg/mL).The antioxidant activities of the three fractions were evaluated by the following in vitro systems: Total antioxidant capacity, superoxide and hydroxyl radical scavenging, ferrous chelating activity and reducing power. The fractions were found to have different levels of antioxidant activity in the systems tested. F1.5v shows the highest activity, especially in the ferrous chelating system, with 70% of ferrous inhibiting at 1.0 mg.mL-1. Finally, all the fractions showed dose-dependent antiproliferative activity against HeLa cells. The fractions F1.5v and F2.0v presented the highest antiproliferative activity at 2.0 mg/mL with 42.7% and 37.0% of inhibition, respectively. Ours results suggests that the sulfated polysaccharides from seaweed G. caudata are promising compounds in antioxidant and/or antitumor therapy

Produção de enzimas quitosanolíticas utilizando Paenibacillus ehimensis e Paenibacillus chitinolyticus para obtenção de quitoologossacarídeos

The acquisition of oligosaccharides from chitosan has been the subject of several studies in the pharmaceutical, biochemical, food and medical due to functional properties of these compounds. This study aimed to boost its production of chitooligosaccharides (COS) through the optimization of production and characterization of chitosanolytic enzymes secreted by microorganisms Paenibacillus chitinolyticus and Paenibacillus ehimensis, and evaluating the antioxidant potential of the products obtained. In the process of optimizing the production of chitosanase were employed strategies Fractional Factorial Experimental Design and Central Composite Rotatable Design. The results identified the chitosan, peptone and yeast extract as the components that influenced the production of chitosanase by these microorganisms. With the optimization of the culture media was possible to obtain an increase of approximately 8.1 times (from 0.043 to 0.35 U.mL U.mL-1) and 7.6 times (from 0.08 U.mL-1 to 0.61 U.mL-1) in the enzymatic activity of chitosanase produced by P. chitinolyticus and P. ehimensis respectively. Enzyme complexes showed high stability in temperature ranges between 30º and 55º C and pH between 5.0 and 9.0. Has seen the share of organic solvents, divalent ions and other chemical agents on the activity of these enzymes, demonstrating high stability of these crude complexes and dependence of Mn2+. The COS generated showed the ability of DPPH radical scavenging activity, reaching a maximum rate of scavenging of 61% and 39% when they were produced with enzymes of P. ehimensis and P. chitinolyticus respectively. The use of these enzymes in raw form might facilitate its use for industrial applications

Ação Sacietogênica de um inibidor de tripsina da semente de tamarindo (Tamarindus indica L.)

The seeds are excellent sources of proteinase inhibitors and have been highlighted owing to various applications. Among these applications are those in effect on food intake and weight gain that stand out because of the increasing number of obese individuals. This study evaluated the effects of trypsin inhibitor present in the seed of tamarind (Tamarindus indica L.) reduction in weight gain, biochemical and morphological alterations in Wistar rats. For this, we partially purified a trypsin inhibitor tamarind seed. This inhibitor, ITT2 at a concentration of 25 mg / kg body weight, over a period of 14 days was able to reduce food intake in rats (n = 6) by approximately 47%, causing a reduction in weight gain approximately 70% when compared with the control group. With the evaluation of the in vivo digestibility was demonstrated that the animals lost weight due to satiety, presented by the reduction of food intake, since there were significant differences between true digestibility for the control group (90.7%) and the group treated with inhibitor (89.88%). Additionally, we checked the deeds of ITT2 on biochemical parameters (glucose, triglycerides, total cholesterol, high-density lipoprotein, low-density lipoprotein, glutamic-pyruvic transaminase, glutamic oxaloacetic transaminase, gamma glutamyl transferase albumin, globulin, total protein and C-reactive protein) and these, when assessed in the study groups showed no statistically significant variations. We also evaluate the histology of some organs, liver, stomach, intestine, and pancreas, and showed no changes. And to evaluate the effect of trypsin inhibitor on food intake due to the satiety is regulated by cholecystokinin (CCK) were measured plasma levels, and it was observed that the levels of CCK in animals receiving ITT2 were significantly higher ( 20 + 1.22) than in animals receiving only solution with casein (10.14 + 2.9) or water (5.92 + 1.15). Thus, the results indicate that the effect caused ITT2 satiety, reducing food intake, which in turn caused a reduction in weight gain in animals without causing morphological and biochemical changes, this effect caused by the elevation of plasma levels CCK

Análise por meio de espectroscopia de emissão óptica das espécies ativas em nitretação iônica e gaiola catódica

Plasma process like ionic nitriding and cathodic cage plasma nitriding are utilized in order to become hard surface of steels. The ionic nitriding is already accepted in the industry while cathodic cage plasma nitriding process is in industrial implementation stage. Those process depend of plasma parameters like electronic and ionic temperature (Te, Ti), species density (ne, ni) and of distribution function of these species. In the present work, the plasma used to those two processes has been observed through Optical Emission Spectroscopy OES technique in order to identify presents species in the treatment ambient and relatively quantify them. So plasma of typical mixtures like N2 H2 has been monitored through in order to study evolution of those species during the process. Moreover, it has been realized a systematic study about leaks, also thought OES, that accomplish the evolution of contaminant species arising because there is flux of atmosphere to inside nitriding chamber and in what conditions the species are sufficiently reduced. Finally, to describe the physic mechanism that acts on both coating techniques ionic nitriding and cathodic cage plasma nitriding