Aplicação da metodologia de planejamento de experimentos para formulação de massas cerâmicas para telhas

Rio Grande do Norte State stands out as one great producer of structural clay of the brazilian northeastern. The Valley Assu ceramic tiles production stands out obtained from ilitics ball clays that abound in the region under study. Ceramics formulation and the design of experiments with mixture approach, has been applied for researchers, come as an important aid to decrease the number of experiments necessary to the optimization. In this context, the objective of this work is to evaluate the effects of the formulation, temperature and heating rate in the physical-mechanical properties of the red ceramic body used for roofing tile fabrication of the Valley Assu, using design of mixture experiments. Four clays samples used in two ceramics industry of the region were use as raw material and characterized by X-ray diffraction, chemical composition, differential thermal analysis (DTA), thermogravimetric analysis (TGA), particle size distribution analysis and plasticity techniques. Afterwards, they were defined initial molded bodies and made specimens were then prepared by uniaxial pressing at 25 MPa before firing at 850, 950 and 1050 ºC in a laboratory furnace, with heating rate in the proportions of 5, 10 e 15 ºC/min. The following tecnologicals properties were evaluated: linear firing shrinkage, water absorption and flexural strength. Results show that the temperature 1050 ºC and heating rate of 5 ºC/min was the best condition, therefore presented significance in all physical-mechanical properties. The model was accepted as valid based of the production of three new formulations with fractions mass diferents of the initial molded bodies and heated with temperature at 1050 ºC and heating rate of 5 ºC/min. Considering the formulation, temperature and heating rate as variables of the equations, another model was suggested, where from the aplication of design of experiments with mixtures was possible to get a best formulation, whose experimental error is the minor in relation to the too much formulations

Potencialidades do uso do blog em educação.

This research is an interpretative analysis of the type participatory research, developed in a qualitative and quantitative use of the blog as a support to a specific discipline, in order to identify the potential evident from its use. The report discusses the changes that have occurred in contemporary society, relating to the development of information technologies and communication (ITC s), presents a brief review of the historical background of the Internet and its use as an aid to education, emphasizing some environments inserted media the Internet, focusing on the main blog - its concept, origin and categorization, and analyzes the concepts of using the blog from the dialogues with teachers and students of pedagogy course at the Federal University of Rio Grande do Norte. Started from the assumption that the use of technological resources, such as blogging, with strictly educational purposes, can extend the knowledge beyond the walls of the classroom, thus creating a dialogic and interactive environment. Using data collected through interviews, questionnaires and observation, we seek to understand the object of study as a supportive environment for the teaching of a subject, raising some theoretical and methodological questions about its application to educational practice, and possible contributions to the construction of knowledge. The results indicate that there are several capabilities that make the blog a space conducive to teaching and learning process, and relates the concepts of the study participants about their use, highlighting the most important places to be solved, so that teachers and students to take ownership of knowledge necessary for capacity building required by the contemporary social context, due to the advancement of science and technology.

Arquitetura inteligente fuzzy para monitoramento de sinais vitais de pacientes: um estudo de caso em UTI

The area of the hospital automation has been the subject a lot of research, addressing relevant issues which can be automated, such as: management and control (electronic medical records, scheduling appointments, hospitalization, among others); communication (tracking patients, staff and materials), development of medical, hospital and laboratory equipment; monitoring (patients, staff and materials); and aid to medical diagnosis (according to each speciality). This thesis presents an architecture for a patient monitoring and alert systems. This architecture is based on intelligent systems techniques and is applied in hospital automation, specifically in the Intensive Care Unit (ICU) for the patient monitoring in hospital environment. The main goal of this architecture is to transform the multiparameter monitor data into useful information, through the knowledge of specialists and normal parameters of vital signs based on fuzzy logic that allows to extract information about the clinical condition of ICU patients and give a pre-diagnosis. Finally, alerts are dispatched to medical professionals in case any abnormality is found during monitoring. After the validation of the architecture, the fuzzy logic inferences were applied to the trainning and validation of an Artificial Neural Network for classification of the cases that were validated a priori with the fuzzy system

Controvérsias sobre a natureza da luz: uma aplicação didática

Researches in the field of Science Teaching have shown, in recent decades, that students from high school level have difficulties in understanding basic concepts of science, in general, and physics, in particular. The specific literature indicates, as a priority for a scientific education of better quality, a more structured understanding about science. This work proposes the introduction of elements of History and Philosophy of Science in high school as an aid to learning the concepts of optics, in general, and of aspects concerning the nature of science, specifically. Making use of historical episodes regarding the controversy on the nature of light, especially during the seventeenth and eighteenth centuries, as well as clippings of the history of optics in relation to the development of models that explain the process of vision, we formulated a teaching unit and implemented it on two night high school classes of a public school in the city of Parnamirim (RN). The unit involved, primarily, the reading of three historical texts containing written questions followed by a collective debate ("moot"). The results indicated some difficulties in overcoming the misconceptions related to the process of vision and the nature of light. Nevertheless, we believe that the teaching unit has succeeded in relation to the learning of most students, both in relation to a better understanding of science as well as concepts of optics

Prevalência e fatores associados a lesões labiais e periorais decorrentes da exposição solar em trabalhadores de praia

This study aimed to verify the prevalence of lip and perioral lesions in worker who were under sunshine on the beaches of Natal/RN and to investigate possible associations of these with sociodemographic, occupational and general health variables. For this, 362 individuals who had one of the urban beaches (Ponta Negra / Environment / Redinha) in the city of Natal/RN as a working environment in the study. We excluded people under 18 years old. Data collection was done through epidemiological analysis and extra-oral validated questionnaire with questions that characterize socioeconomic and demographic factors, occupational exposure and general health. The male subjects (72.6%) were the majority in the sample. The people who worked directly exposed to high peaks of ultraviolet radiation, as well as informal workers predominated. Considering the total sample of individuals, ephelides in the perioral region (33.7%) and labial region (24.0%), solar lentigo perioral (15.2%) and actinic cheilitis (13.8%) stood out as the most prevalent lesions. Indoor workers and those who had a habit occurrence of injuries by 19% and 21% respectively higher when compared to outdoor workers and people without habits. The variable use of cap / hat was associated with the presence of cold sores (Qui2 = 1,328, p = 0,058). On the threshold of significance, the type of work was also associated with lesions in lip occurrence (p = 0,042). Men showed a lower incidence of perioral lesions when compared to female workers (PR=0,716, p valor = 0,002). The present study showed high prevalence of lip and perioral lesions. The premalignant lesions were the most identified, both as in lip skin. It is important therefore to be encouraged to adopt protective measures against excessive sun exposure, fairly and consistently

Trabalhadores por conta própria: O trabalho dos vendedores ambulantes da passarela do Natal shopping e do Via Direta

This study aid to understand the work conditions of street vendors located on the sidewalks of two malls in Brazil Northeast Natal / RN - Both malls Natal Shopping and Via Direta, to analyze their inclusion in the informal economy and to study the supposed autonomy provided by work as self-employment in its both aspects economic and social analyzing the importance on the condition of "masters of their own business" has for the street vendors, as an alternative to not submission to the figure of the boss, that represents the exploitation of one class over another. The theoretical and methodological aspects that support this study was aimed in discussion on the restructuring of production, considering its effects on the world of work, pointing to unemployment as one of the potencies element of excluded processes that exciting workers to engage in the informal market. Informality is presented as a survival strategy and as integrating part of the reproduction of capital. This research was conducted under a critical perspective, whish has been utilized quantitative and qualitative analyses. The results of this study format questions that provided during the research process the socio-economic characterization of workers, main cause of this study, and how street vendors expres their status of workers as self-employed for their work, and the perception that they have on their form of inclusion in the informal market.

Efeitos de tempestades magnéticas em sinais de gps, em Natal, Brasil

Satellites signals present disturbances (scintillations), due to presence of irregularities in the ionospheric plasma. In the present work, we dedicate to the study of the attenuation of these scintillations that is, an improvement in the signal, during the main magnetic storm phase during the period of October 2006 to February 2007. Using amplitude of scintillation 1.5GHz (L1) data of the net of satellites GPS, in the ionospheric station of Natal (5.84o S, 35.20o O, -20o dip) and geomagnetic indices, during the minimum solar cycle (referred to as cycle 23), demonstrating its anti-correlation between magnetic activity (Kp) and index of scintillation () (Bonelli2005 method, that works for solar maximum, Bonelli(2005)). These results show that these storms correspond to category I of Aarons (1991). The magnetic storms can generate irregularities when the electric feld of penetration eastward on the pre-reversal hour intensificating that and can too generate irregularities on midnight and sunlight period. The limitation of the method applied here is that it is not considering some storms that had also occurred during equinox and summer in the Brazilian region. For this reason, we will use additional data of the stations of São João de Cariri (Imager and Photometer) and of the station at Fortaleza (Digissonde data), as aid to analyze these storms. The storms that had been left out by the applied method, fit in the other two categories of Aarons, with one only exception (storm of January, 02). We show that in the day of the main phase of the magnetic storm, and with presence of bubbles (according to data of the Imager and Photometer), the speed of vertical drift ~E ~B (hF=t) is below 20m/s, that is the threshold found for Anderson al., (2004) (>20m/s as condition favorable to the formation of irregularities and increase in the scintillation index). This reduction of the speed is due to solar minimum

Representações arquitetônicas na concepção projetual: um estudo com arquitetos e urbanistas do Rio Grande do Norte

The architect materializes his ideas using architectural representations that acts differently during the design process, as instrument that expresses his creatives ideas, as communication between the designer and the client, or as project documentation for its execution (DURAND, 2003). In this paper, it’s been discussed the connexion between the architectural representations and the design process, in a professional context, focusing on representation as an aid to conception. The general aim is to understand the role of architectural representations in the design process by identifying ways of appropriation of their types and resources. The investigation was developed through the theoretical and conceptual studies about the mentioned themes, and the empirical and qualitative research, with architects from the state of Rio Grande do Norte, Brazil, which was developed in two stages: the first one, by filling an electronic form, and the second one, by case studies through execution of design exercises. The results of indirect research showed that the majority of architects and urbanists believes that the way it use the types and representation resources may interfere in design concept. And, after the completion of the case studies, was showed that, motivated by different design conditions, most designers has used the representations differently, which is reflected in different design conceptions.

Aplicação da metodologia de planejamento de experimentos para formulação de massas cerâmicas para telhas

Rio Grande do Norte State stands out as one great producer of structural clay of the brazilian northeastern. The Valley Assu ceramic tiles production stands out obtained from ilitics ball clays that abound in the region under study. Ceramics formulation and the design of experiments with mixture approach, has been applied for researchers, come as an important aid to decrease the number of experiments necessary to the optimization. In this context, the objective of this work is to evaluate the effects of the formulation, temperature and heating rate in the physical-mechanical properties of the red ceramic body used for roofing tile fabrication of the Valley Assu, using design of mixture experiments. Four clays samples used in two ceramics industry of the region were use as raw material and characterized by X-ray diffraction, chemical composition, differential thermal analysis (DTA), thermogravimetric analysis (TGA), particle size distribution analysis and plasticity techniques. Afterwards, they were defined initial molded bodies and made specimens were then prepared by uniaxial pressing at 25 MPa before firing at 850, 950 and 1050 ºC in a laboratory furnace, with heating rate in the proportions of 5, 10 e 15 ºC/min. The following tecnologicals properties were evaluated: linear firing shrinkage, water absorption and flexural strength. Results show that the temperature 1050 ºC and heating rate of 5 ºC/min was the best condition, therefore presented significance in all physical-mechanical properties. The model was accepted as valid based of the production of three new formulations with fractions mass diferents of the initial molded bodies and heated with temperature at 1050 ºC and heating rate of 5 ºC/min. Considering the formulation, temperature and heating rate as variables of the equations, another model was suggested, where from the aplication of design of experiments with mixtures was possible to get a best formulation, whose experimental error is the minor in relation to the too much formulations