68 resultados para Peças desenhadas


Relevância:

10.00% 10.00%

Publicador:

Resumo:

Recent years have seen a significant growth in surface modifications in titanium implants, resulting in shorter healing times in regions with low bone density. Among the different techniques, subtraction by chemical agents to increase oxidation has been applied for surface treatment of dental implants. However, this technique is generally unable to remove undesirable oxides, formed spontaneously during machining of titanium parts, raising costs due to additional decontamination stages. In order to solve this problem, the present study used plasma as an energy source to both remove these oxides and oxidize the titanium surface. In this respect, Ti disks were treated by hollow cathode discharge, using a variable DC power supply and vacuum system. Samples were previously submitted to a cleaning process using an atmosphere of Ar, H2 and a mixture of both, for 20 and 60 min. The most efficient cleaning condition was used for oxidation in a mixture of argon (60%) and oxygen (40%) until reaching a pressure of 2.2 mbar for 60 min at 500°C. Surfaces were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), atomic force microscopy (AFM), adhesion and cell proliferation. SEM showed less cell spreading and a larger number of projections orfilopodia in the treated samples compared to the control sample. AFM revealed surface defects in the treated samples, with varied geometry between peaks and valleys. Biological assays showed no significant difference in cell adhesion between treated surfaces and the control. With respect to cell proliferation, the treated surface exhibited improved performance when compared to the control sample. We concluded that the process was efficient in removing primary oxides as well as in oxidizing titanium surfaces

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Drugs advertising is one of the most important marketing resources used by the pharmaceutical industry to induce people to buy these products although they do not have the real necessity to use them. The purpose of this article is to evaluate drugs advertisings transmitted on radio stations in Natal/RN, from October 2007 to September 2008. Were collected 228 advertising pieces, where, 21 were different among themselves and corresponded to 15 drugs. The results showed that 73,3% of the drugs ads were announced on AM station and 26,7% on FM station. The majority of the drugs were constituted of analgesics (26%), following by antiacids, vitamins, phitotherapics (13% each). The legal analysis showed that each advertising had some kind of infraction. The omission of the registration number happened in each advertising, following by the totally lack of contraindications (95,2%) and contraindications DCB/DCI (76,2%). In 42,9% advertisements were observed the relation between drugs use and physique/intellectual/emotional/sexual performance and/or beauty and 33% of them had abusive exploration of illnesses. The obligatory warning was omitted in 28,6% and the offer of financial bonus happened in 9,5% cases. The content analysis demonstrated that the most persuasion and convincing elements observed were indicatives of consumption appeal (34,2%). The study indicates the necessity of the topic drugs advertisements to be treated in a wide context, that is, to be discussed as a public health concern. Although the advertising regulation and inspection is the State responsibility , this should be shared with the advertising agency, pharmaceutical industry and media. Furthermore, it is indispensable to inform and to conscience the population of their rights in such mistaken situation

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The present study aimed to characterize the thermal profile of wood fired oven used by the red ceramic industry in Parelhas, in the Seridó region/RN, aiming to propose structural interventions that can contribute to increasing productivity and product quality, optimize wood consumption and mitigate existing losses during the burning process. The study was conducted at Cerâmica Esperança in the city of Parelhas -RN, Brazil, during the period from August 2012 to September 2013. Four treatments were performed with three replicates, ie, with, a total of 12 experimental units (burnings). In the first stage 4 treatments were performed with three replicates, totaling 12 experimental units (firings). In the second stage 2 treatments were performed with three replications, totaling 6 experimental units (firings). The physical characteristics of the wood were analyzed using standard NBR 11941 and NBR 7190 for basic density and moisture, respectively. The clay was used as a reference parameter for distinguishing treatments. For both the analysis and characterization was carried out using techniques of fluorescence X (XRF) rays, X-ray diffraction (XRD) analysis, particle size analysis (FA). In the first and second stages were monitored: the time during the firing process, the amount of wood used at each firing, the number of parts enfornadas for subsequent determination of the percentages of losses, but also product quality. To characterize the thermal profile of the oven, we measured the temperature at 15 points scored in the surface charge put into the oven. Measurements were taken every 30 minutes from preheat until the end of burning, using a pyrometer laser sight sighting from preheating until the end of burning. In the second step 12 metal cylinders distributed on the oven walls, and the cylinder end walls 8 of the furnace 2 and rollers on each side walls are installed equidistant to 17 cm from the soil and the surface 30 of the wall are installed. The cylinders distributed on the front were placed 50 cm above the furnace, and the base of the oven 20 cm distant from the ground. 10 also thermocouples were installed, and five thermocouples distributed 1.77 cm above the combustion chambers, and one thermocouple on each side, and three thermocouples in front of the oven. We carried out the measurements of the temperatures every 1 hour during the burning two hours in cooling the cylinders with a pyrometer and thermocouples for dattaloger. These were fixed with depth of 30 cm from the wall. After statistical analysis it was found that: the thermal profile of the furnace surface and at different heights was heterogeneous; and the ranges of density and moisture content of wood are within recommended for use as an energy source standards. We conclude that even at low temperatures reached during firing there was a significant production of good quality products, this is due to high concentrations of iron oxide and potassium oxide found in clay, which lowers the melting point of the piece. The average burn time for each step varied 650-2100 minutes wood consumption was on average 20 m3, product quality was on average 16% of first quality, 70% second, third and 5% to 10% loss . The distance between the wire and the surface of the oven was a significant parameter for all treatments, but with different variations, meaning that the wire should not be so generic and unique form, used as a criterion for completion of the burn process. The central part of the furnace was the area that reached higher temperature, and in a unified manner, with the highest concentration of top quality products. The ideal temperature curve, which provided the highest quality of ceramic products was achieved in the central part of the furnace

Relevância:

10.00% 10.00%

Publicador:

Resumo:

This work aims to study the associations as mediating the process of social change and its importance for local development. The hypothesis is that associations, but bring dynamism to the smaller cities and improve the living conditions of their members, relegated to the background social sustainability, understood this as a permanent exercise of mobilization and participation in community life. The assumptions of the study are that the practice group has influenced the processes of local development in Brazilian rural municipalities through the mediation of government programs and projects aimed at combating rural poverty require social organization for their achievement. The concept of local development in this work was rescued from studies of political economy and sociology. But the concepts of collective action and partnerships advêem studies of political participation and social development of the theory of alternative or solidarity. The party consisted of an empirical case study conducted with four associations of farmers in the municipality of Portalegre-RN. Why choose qualitative study was used the technique of semi-structured interviews with the chairmen I members of associations and other actors considered essential to understanding the study (religious leaders, local political power and chairman of the union of rural workers), a total of 20 interviews, in addition to the observations of field and documentary research in records of the.ir own organizations. The survey results show that the performance of groups of farmers are key components and determinants for the production I marketing of agricultural products and for boosting the economy, as well as security for minimum levels of citizenship. Yet we are still in a space purpose of social change, which comes to confirm the initial hypothesis of this work

Relevância:

10.00% 10.00%

Publicador:

Resumo:

This research work deals with the compilation of a dictionary on clothing terminology intended to be used as a pedagogic tool as part of the teaching and learning process in the Textile Engineering Course at the Federal University of Rio Grande do Norte. The main terms were selected and assessed by a team of textile teachers and students with the objective to be structured as a conceptual body of information on the following sub-areas of clothing terminology: materials (fabrics and trimmings) and products (garments). This research comprises three main steps: (a) characterization and understanding of the technical vocabulary in the clothing area as well as the identification of a pedagogic demand for a dictionary on clothing terminology, clearly expressed by the textile lecturers and students involved in the assessment of the need and validation of this project development; (b) a proposal for a specific methodology for the compilation of the dictionary which could help the communication process in the lecturing of clothing terminology and (c) based on the terminological principles and the technique of focal groups the dictionary was assessed. The technique of focal groups was used in the first step. In the second step the technique used was that of the terminological methodology adapted to the teaching approach in the Textile Course. In the third step the technique of focal groups was again utilized. It was observed that the main concern of lecturers and students is the lack of a standardized vocabulary, which renders difficult the communication process in both the teaching and learning activities as well as the professional ones in the textile industries. Various aspects, which can overlap, cause this lack of standardization. The main ones pointed out by the study team in the focal groups are: usage of regional words or expressions, usage of foreign words or expressions, analogies, and the low level of formal education, mainly among the industry workers. Another aspect to be considered is the lack of textile literature written in the Portuguese language of Brazil. This evidence shows the importance of a clothing terminology dictionary which will benefit both the education and professional activties in this field of knowledge. This dictionary will also give a substantial contribution to terminological standardization in our research field. With view to fulfill this demand, a dictionary of clothing terminology was compiled with 760 main entries, according to the modern practice in terminology with the necessary modifications concerning our needs. The result of the dictionary assessment was very assertive regarding its structure, contents and possible use in various contexts. The team work emphasized their contribution to the standardization process of the terms that proved to be one of the most important and difficult aspects of this researh work. The significance of this structured terminological dictionary was confirmed by the focal group participants relating to its use for teaching and learning activities, as a reference book, as a source of technical information and also as a tool for pedagogic studies and planning, as well as a significant collaboration to the pedagogic practices in the textile engineering course at University or any other educational institution. Besides, this dictionary can also be used to supply information within the textile field. We are aware that the present work will not exhaust the objectives of this research due to its limitations in opposition to the vast complexity demanded by the compilation of a complete work including all the areas and sub-areas of textile engineering. However, it is an important source for dissemination of concepts on the field of clothing terminology and a tool to effective standardization of the terms used in this subject field

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The aim of this research is the analysis of the history of the Normal Course in the 1st period in Assu, Rio Grande do Norte, since its foundation by the state law no. 621, de 06 December 1951 until its demise, with the implementation of the Course of the Magisterium, by Federal Law 5692 from August 11, 1971. The goal is to answer how it was constituted the operation and the educational practices of this institution, teacher trainers, throughout its existence. For this, we analyze the institution's documents in focus interviews, legislation, of the education, newspapers and books of the season, guiding itself by the studies of Chartier (1991), Elias (2001), Certeau (2001), Frago (1995), Magalhães (2005) and Julia (2001). When dealing with an educational institution, the central category of analysis is the school culture, in which supported the cutting of specific categories of study: the entrance into the Normal Course, the conferring of a degree, the "Normalista Week‖ in Assu and formative elements. The Normal Course from 1st cycle formed teachers in a basic level, differing themselves from schools of teacher education of 2nd Cycle. It was founded in Assu as Regional Training Course and called Ginásio Normal in 1961.In the temporal cut studied, 279 women and 07 men were graduated as Regents of Elementary School, demonstrating a school attended virtually by women. In the narrative, it is restored to the inclusion of female students in the Normal Course, focusing on the processes of registration and the admission exams, graduation events, imbued with discourses on the social role of the teacher and the Party Normalista Week, which valued the sense of belonging with of students to the profession. Through theater plays in the school, of practices forming behaviors and stages of female students in elementary school, training elements are reassembled, demonstrating the discourse of modern education intermingled with the Christian Catholic values of the culture for female education. The reconstruction of the historical identity of this institution sometimes close, sometimes unique, when confronted with other schools of teacher training brings a contribution to the setting of the history of schooling in the state of Rio Grande do Norte

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The present study analyzes the ethnomatematics practices presents in the creation of the geometric ornaments of the icoaraciense ceramic, originated and still practiced in the neighborhood of Paracuri, District of Icoaraci, belonging to Belém, capital of the State of Pará/Brasil. The object of our study was centered at the workshops supplied by the artisans master of the School of Arts and Occupations, Master Raimundo Cardoso. Referred school provides to its students, formation at fundamental level as well professional formation, through vocational workshops that help to maintain alive the practice of the icoaraciense ceramic. Our interest of researching that cultural and vocational practice appeared when we got in touch with that School, during the development of activities of a discipline of the degree course of mathematics. In order to reach our objective, we accomplished, initially, a research about the icoaraciense ceramic historic, since the first works with the clay until to the main characteristics of that ceramic. Soon afterwards, we discussed on ethnomatematics, culture, knowledge, cognition and mathematical education. At the end, we analyzed the creation of the geometric ornaments of the icoaraciense ceramic, considering the proportion concepts, symmetry and some geometry notions, that are used by the artisans when they are ornamenting the pieces of that ceramic. We verified that, in spite of the artisans, usually, do not demonstrate to possess a bit of domain on the mathematical concepts that they are working with, for instance, the ones of translaction symmetry, rotation and reflection, they demonstrate full safety in the use of those concepts, as well as the capacity to recognize them, even if in a singular specific and very peculiar way, what opens the possibility of a partnership among mathematics teachers and master-artisans of the archeological ceramic and icoaraciense workshops

Relevância:

10.00% 10.00%

Publicador:

Resumo:

O estudo que ora se apresenta, examina a formação e aparição do discurso da educação higienista no Jornal das Moças, em 1926, ano de criação do periódico, na cidade de Caicó. Para tanto, partimos da hipótese de que ele se constituiu em um privilegiado veículo para a intervenção educativa da sociedade caicoense, no período inicial do Regime Republicano, reconhecido pelas intensas movimentações sociais. Para a execução do proposto, optou-se pela base teórica estabelecida pelo paradigma historiográfico instaurado pela Escola dos Annales, que permitiu a conjugação entre os pressupostos conceituais de Norbert Elias, Roger Chartier e Michel Foucault, com vistas a abranger um estudo da configuração social em que se formou a prática discursiva disposta no jornal em estudo, tendo como linha investigativa as proposições da história cultural. Quanto à compreensão e tratamento metodológico do discurso, contido como prática materialmente construída, aderiu-se ao enfoque analítico apresentado nas postulações foucaultianas, nas quais são considerados os conjuntos das formações enunciativas, esparsas em fontes e documentos que, coligidas, formam grupos de enunciados pertinentes à descrição de um mesmo objeto. A principal fonte de pesquisa foi a coleção dos números do Jornal das Moças, editados, apenas, em 1926, parte dela composta por peças documentais originais, a que tivemos acesso nos locais de pesquisa durante o esforço investigativo, como o Acervo da Biblioteca Central Zila Mamede, o Laboratório de Documentação Histórica do Centro de Ensino Superior do Seridó, da Universidade Federal do Rio Grande do Norte. Desse modo, constatou-se que a prática discursiva que se examinou, na constituição desta dissertação, foi um meio para a compreensão das representações advindas do momento histórico e social das primeiras décadas do século XX, quando se tornam evidentes as articulações discursivas de uma prática pedagógica como dispositivos higienistas

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The Six Sigma methodology has received considerable attention in the last two decades. This is due to its great potencial to reduce processes variability, through the use of accurate data, facts and statistical techniques. The methodology seeks to improve the quality of products and services, maximizing the company s financial performance. Specifically, its implementation and results in medium-sized textile enterprises is unknow, although there are signs that the methodology can be applied with success. Considering this scenario, the goal of this research is to describe the application of the Six Sigma methodology in a médium-sized textile company specialized in the production of male shirts in the satate of Rio Grande do Norte, Brazil. First, we present a literature review, seeking to highlight the themes of quality, Six Sigma and its methodology for improvement. Then, we show the implementation of the project selected, depicting the steps and procedures that must be performed. The results confirm the efficiency of Six Sigma in providing significant gains to companies. It is observed substantial improvements in the speed of product development and the flexibility of the parts produced, reducing the process lead time from 12.5 to 6.2 days, which means a performance improvement of over 50%. This leads also to cultural and behaviour change, creating motivation for implementation of new projects and a continuous search for knowledge

Relevância:

10.00% 10.00%

Publicador:

Resumo:

This paper aims to conduct a study to evaluate and measure the possible impact that the unavailability of spare parts can have on customer satisfaction for car dealerships in the post-sales. A theoretical-conceptual review on the subject of satisfaction and loyalty, on the backdrop of the reality of the automobile market, allowed the construction of a research tool dedicated to collect opinions of car owners, to allow an analysis empirical relationship between the availability of parts, repairs or scheduled service possible, and change or stay on the mark on the occasion of change of vehicle. 236 forms were applied to car owners in the city of Natal / RN. The results obtained in this survey allowed the identification of the unavailability of parts as a significant factor, among others, the motivation for the customer to switch brands. Collaterally, we could also conclude that the dynamics of change in marks, whatever its motivation, is reflected in the perceived positions of the different brands as the market share both in strictly quantitative terms and in terms of relative positioning, with significant changes in the ranking of consumer preferences for different brands available

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The progressing cavity pump artificial lift system, PCP, is a main lift system used in oil production industry. As this artificial lift application grows the knowledge of it s dynamics behavior, the application of automatic control and the developing of equipment selection design specialist systems are more useful. This work presents tools for dynamic analysis, control technics and a specialist system for selecting lift equipments for this artificial lift technology. The PCP artificial lift system consists of a progressing cavity pump installed downhole in the production tubing edge. The pump consists of two parts, a stator and a rotor, and is set in motion by the rotation of the rotor transmitted through a rod string installed in the tubing. The surface equipment generates and transmits the rotation to the rod string. First, is presented the developing of a complete mathematical dynamic model of PCP system. This model is simplified for use in several conditions, including steady state for sizing PCP equipments, like pump, rod string and drive head. This model is used to implement a computer simulator able to help in system analysis and to operates as a well with a controller and allows testing and developing of control algorithms. The next developing applies control technics to PCP system to optimize pumping velocity to achieve productivity and durability of downhole components. The mathematical model is linearized to apply conventional control technics including observability and controllability of the system and develop design rules for PI controller. Stability conditions are stated for operation point of the system. A fuzzy rule-based control system are developed from a PI controller using a inference machine based on Mandami operators. The fuzzy logic is applied to develop a specialist system that selects PCP equipments too. The developed technics to simulate and the linearized model was used in an actual well where a control system is installed. This control system consists of a pump intake pressure sensor, an industrial controller and a variable speed drive. The PI control was applied and fuzzy controller was applied to optimize simulated and actual well operation and the results was compared. The simulated and actual open loop response was compared to validate simulation. A case study was accomplished to validate equipment selection specialist system

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Due of industrial informatics several attempts have been done to develop notations and semantics, which are used for classifying and describing different kind of system behavior, particularly in the modeling phase. Such attempts provide the infrastructure to resolve some real problems of engineering and construct practical systems that aim at, mainly, to increase the productivity, quality, and security of the process. Despite the many studies that have attempted to develop friendly methods for industrial controller programming, they are still programmed by conventional trial-and-error methods and, in practice, there is little written documentation on these systems. The ideal solution would be to use a computational environment that allows industrial engineers to implement the system using high-level language and that follows international standards. Accordingly, this work proposes a methodology for plant and control modelling of the discrete event systems that include sequential, parallel and timed operations, using a formalism based on Statecharts, denominated Basic Statechart (BSC). The methodology also permits automatic procedures to validate and implement these systems. To validate our methodology, we presented two case studies with typical examples of the manufacturing sector. The first example shows a sequential control for a tagged machine, which is used to illustrated dependences between the devices of the plant. In the second example, we discuss more than one strategy for controlling a manufacturing cell. The model with no control has 72 states (distinct configurations) and, the model with sequential control generated 20 different states, but they only act in 8 distinct configurations. The model with parallel control generated 210 different states, but these 210 configurations act only in 26 distinct configurations, therefore, one strategy control less restrictive than previous. Lastly, we presented one example for highlight the modular characteristic of our methodology, which it is very important to maintenance of applications. In this example, the sensors for identifying pieces in the plant were removed. So, changes in the control model are needed to transmit the information of the input buffer sensor to the others positions of the cell

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The potential market of the metropolitan area of Salvador accounts for the estimated consumption of roughly 800 million horizontally perforated extruded clay bricks a year. The growing demand of consumers along with the competitiveness of the structural ceramic sector has driven forward a number of recent efforts and investments towards improving the quality of structural ceramics. In this scenario, the present study focused on sampling and evaluating the conformity of 8-hole horizontally perforated extruded clay bricks manufactured by different plants (A, B and C) in the metropolitan area of Salvador. In addition, representative clay and sandy-clay materials were collected from each plant and characterized by conventional physical, chemical and mineralogical techniques. Finally, experimental compositions designated as A, B and C, according to the source, were prepared by mixing different contents of the raw materials collected in the plants, fired at different temperatures and characterized. The results revealed a series of non conformities regarding ABNT guidelines. The characterization of raw materials revealed the presence of kaolinite and ilite in concentrations ranging from 64 to 90 wt.% along with free quartz (10 - 25%). The sandy-clay samples consisted basically of kaolinite. All raw materials depicted low contents of organics, amorphous constituents, alkaline oxides and feldspar. An analysis of the firing behavior of all different ceramic compositions revealed that the linear contraction of composition A was rather significant considering the temperature range evaluated, and it justifies the significant dimensional non conformity that was shown by bricks made with the ceramic A

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The production of red ceramic is an industrial activity that causes an intense impact. The manufacture of its products considerably increases the demand for natural resources, mainly with the extraction of raw material. The ceramic material produced generates waste, such as ash firewood and chamote. The residue from the beneficiation of kaolin is deposited in a poor, degrades the environment and contaminate water sources and soil, constituting in this manner, ecological disasters. The main objective of this work is to develop the formulation of a ceramic product consisting solely of industrial solid wastes, from ceramic tiles, (chamote) residue of kaolin and ash firewood. It is assumed that this product made in the laboratory can be used in coatings, wall and floor. The aim is to facilitate the replacement of the raw material of original composition of a ceramic body, for waste, while the process of production equal to the conventionally used, so that the properties of the product are reproduced. This work is characterized waste as its chemical composition, analysis of particle size, X-ray diffraction and thermal behavior. Several formulations were studied. The mass of waste was prepared by dry process, pressed to 25 MPa, and then burned in muffle type oven to 850, 950, 1050 and 1150 °C. The results showed that it is technically possible to produce porous tiles only with waste. It was found that the formulations of bodies play a key role in the properties of the final product, as well as the sintering temperature and heating rates. RN in the waste of kaolin is estimated at 15,000 t/month, about 3,000 gray t/month and chamote with 10 million pieces/month damaged. The presence of carbonates of calcium and magnesium at 1050 ° C results in an appropriate porosity and mechanical strength. The formulation M3JE, composed of 69% waste of kaolin, 7.7% and 23.3% of chamote of gray, became suitable for porous materials with the strength and absorption within the level of national and international standards

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The production of roof tiles in the state of Rio Grande do Norte accounts for around 60% of the total of ceramic pieces produced. There is a need for investment to improve quality and productivity, thereby promoting technological innovations. Accordingly, the aim of this study is to determine the effect of kaolin, potassium feldspar and quartz in two standard formulations, as well as the effect of sintering temperature on the technological properties of linear firing shrinkage, water absorption and bending rupture stress, by fitting the statistical model and using multiple linear regression to assess the relationship between technological properties and independent variables. The raw materials were characterized using the following techniques: X-ray fluorescence (XRF), X-ray diffraction (XRF), rational analysis (RA), differential thermal analysis (DTA) and granulometric analysis (GA). The test specimens were compacted by uniaxial pressure (25 MPa), dried in a stove at 110 ºC for 24 hours and sinterized at 850 ºC, 950 ºC and 1050 ºC and held isothermal for 30 minutes. The results obtained indicate that the addition of kaolin to two standard formulations (M and R) promoted a reduction in water absorption values and an increase in bending rupture stress values. The sintering temperatures for group M that resulted in the lowest linear firing shrinkage and water absorption values were 850 ºC and 950 ºC, respectively, and the highest bending rupture stress values were reached at a temperature of 950 ºC. In the case of group R, the sintering temperature that obtained the lowest water absorption and linear firing shrinkage values was 850 ºC, and the highest bending rupture stress values were attained at a temperature of 1050 ºC. This work explains the statistical approach used to fit the model that describes the relationship between the technological properties and percentage of kaolin, quartz and feldspar, as well as the models that enable predictions, provided that the lower and upper limits of the percentage of clay minerals, flux and quartz used in this study are respected. Statistica 6 software was used and results were obtained by stepwise forward regression