77 resultados para Trabalho : Novas tecnologias
Resumo:
Recently, an amazing development has been observed in telecommunication systems. Two good examples of this development are observed in mobile communication and aerospace systems. This impressive development is related to the increasing need for receiving and transmitting communication signals. Particularly, this development has required the study of new antennas and filters. This work presents a fullwave analysis of reflectarrays. The considered structures are composed by arrays of rectangular conducting patches printed on multilayer dieletric substrates, that are mounted on a ground plane. The analysis is developed in the spectral domain, using an equivalent transmission line method in combination with Galerkin method. Results for the reflection coefficient of these structures are presented and compared to those available in the literature. A good agreement was observed. Particularly, the developed analysis uses the transmission lines theory in combination with the incident potentials and the field continuity equations, at the structures interfaces, for obtaining the scattered field components expressions as function of the patch surface currents and of the incident field. Galerkin method is used to determine the unknown coefficients in the boundary value problem. Curves for the reflection coefficient of several reflectarray geometries are presented as function of frequency and of the structural parameters
Análise espectral de reflectarrays com substrato de duas camadas dielétricas anisotrópicas uniaxiais
Resumo:
Recently, an amazing development has been observed in telecommunication systems. Two good examples of this development are observed in mobile communication and aerospace systems. This impressive development is related to the increasing need for receiving and transmitting communication signals. Particularly, this development has required the study of new antennas and filters. This work presents a fullwave analysis of reflectarrays. The considered structures are composed by arrays of rectangular conducting patches printed on multilayer dieletric substrates, that are mounted on a ground plane. The analysis is developed in the spectral domain, using an equivalent transmission line method in combination with Galerkin method. Results for the reflection coefficient of these structures are presented and compared to those available in the literature. A good agreement was observed. Particularly, the developed analysis uses the transmission lines theory in combination with the incident potentials and the field continuity equations, at the structures interfaces, for obtaining the scattered field components expressions as function of the patch surface currents and of the incident field. Galerkin method is used to determine the unknown coefficients in the boundary value problem. Curves for the reflection coefficient of several reflectarray geometries are presented as function of frequency and of the structural parameters
Resumo:
On this research we investigated how new technologies can help the process of design and manufacturing of furniture in such small manufacturers in Rio Grande do Norte state. Google SketchUp, a 3D software tool, was developed in such a way that its internal structures are opened and can be accessed using SketchUp s API for Ruby and programs written in Ruby language (plugins). Using the concepts of the so-called Group Technology and the flexibility that enables adding new functionalities to this software, it was created a Methodology for Modeling of Furniture, a Coding System and a plugin for Google s tool in order to implement the Methodology developed. As resulted, the following facilities are available: the user may create and reuse the library s models over-and-over; reports of the materials manufacturing process costs are provided and, finally, detailed drawings, getting a better integration between the furniture design and manufacturing process
Resumo:
The objective of this research is the fabrication of a composite reinforced with dyed sisal fiber and polyester matrix for application in the fields such as, fashion, clothing, interior textiles; fashion accessories are some of the examples. For the fabrication of the composite, the sisal fibers were subjected to processes such as: chemical treatment with sodium hydroxide (NaOH) in the removal of impurities; bleaching for removing the yellowish color of the natural fiber and dyeing with direct dyes to confer the colors blue, green and orange. The search for new technologies ecologically correct has become a major concern in recent decades. Studies show that composite polymer reinforced by natural fibers is suitable for a large number of applications, and its use is advantageous in terms of economic and ecological. The dyed fibers were cut to a length of 30 mm, is used in the confection of webs. For this purpose, a web preparer by immersion, developed in the Laboratory of Chemical Textile of UFRN. The composite sheets measuring 300 x 300 x3 mm were molded by compression, with unsaturated orthophthalic polyester as matrix, and the samples in sizes 150 x 25 x 3 mm were cut with the aid of a laser machine, to be subjected to traction and flexion. The mechanical properties of traction and flexion in three points were performed in the Laboratory of metal and mechanical tests of Materials Engineering of UFRN. The resulting samples from the tests were evaluated in scanning electron microscope (SEM) at CTGas RN. On the basis of the analysis of the results from the mechanical tests, it was observed that the composite had good mechanical behavior, both in traction as in flexion. Furthermore, it was observed that in the water absorption test, the samples had a different percentage among themselves, this occurred due to the variation of density found in the fibre webs. The images of the SEM showed the failures from the manufacturing process and the adhesion of fibre/matrix. When the samples were prepared with the dyed fibers to be applied in fashion, the results were positive, and it can be concluded that the main objective of this work was achieved
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The developments in formulating drilling fluids to apply in petroleum fields are based on new technologies and environmental challenges, where the technical performance of a developed drilling fluid is used to produce a minimum environmental impact, showing great economy in costs. It is well known that the potential use of oil-based drilling fluids is limited because these fluids when discharged in the sea do not disperse as much as water-based ones and may form waterproof films in the seabed, having a profound effect on plants and animals living in this environment. The current works have been made in investigating fluids called pseudofluids, which are synthetic ester-based, n-paraffin-based and other fluids formed from inverse emulsion. In this research the principal parameters involved in inverse emulsion process were studied, in laboratory scale, using esters as main component. Others commercial drilling fluids were used as comparative samples, as well as samples from laboratory and field where these drilling fluids are being applied. Concentrations of emulsifier and organophilic clay, which are viscosity donor, were varied to verify the influence of these parameters, in different oil/water ratios (55/45, 60/40, 65/35, 70/30, and 75/25). The salt concentration (NaCl) is an indicative parameter of stability and activity of an esterbased fluid. In this research the salt concentration was varied in 10,000, 20,000, and 50,000 ppm of NaCl. Some rheological properties of the produced fluids were studied, such as: initial gel, plastic viscosity, yield point, and apparent viscosity. Through the obtained rheological measures, the existence of two systems could be verified: fluid and flocculated. It could be noticed that the systems were influenced, directly, by the oil/water ratio and emulsifier, organophilic clay and NaCl concentrations. This study showed the viability to use an ester obtained from a regional vegetable product babaçu coconut oil to obtain an efficient and environmental safe drilling fluid
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With the growth and development of modern society, arises the need to search for new raw materials and new technologies which present the "clean" characteristic, and do not harm the environment, but can join the energy needs of industry and transportation. The Moringa oleifera Lam, plant originating from India, and currently present in the Brazilian Northeast, presents itself as a multi-purpose plant, can be used as a coagulant in water treatment, as a natural remedy and as a feedstock for biodiesel production. In this work, Moringa has been used as a raw material for studies on the extraction and subsequently in the synthesis of biodiesel. Studies have been conducted on various techniques of Moringa oil extraction (solvents, mechanical pressing and enzymatic), being specially developed an experimental design for the aqueous extraction with the aid of the enzyme Neutrase© 0.8 L, with the aim of analyzing the influence variable pH (5.5-7.5), temperature (45-55°C), time (16-24 hours) and amount of catalyst (2-5%) on the extraction yield. In relation to study of the synthesis of biodiesel was initially carried out a conventional transesterification (50°C, KOH as a catalyst, methanol and 60 minutes reaction). Next, a study was conducted using the technique of in situ transesterification by using an experimental design variables as temperature (30-60°C), catalyst amount (2-5%), and molar ratio oil / ethanol (1:420-1:600). The extraction technique that achieved the highest extraction yield (35%) was the one that used hexane as a solvent. The extraction using 32% ethanol obtained by mechanical pressing and extraction reached 25% yield. For the enzymatic extraction, the experimental design indicated that the extraction yield was most affected by the effect of the combination of temperature and time. The maximum yield obtained in this extraction was 16%. After the step of obtaining the oil was accomplished the synthesis of biodiesel by the conventional method and the in situ technique. The method of conventional transesterification was obtained a content of 100% and esters by in situ technique was also obtained in 100% in the experimental point 7, with a molar ratio oil / alcohol 1:420, Temperature 60°C in 5% weight KOH with the reaction time of 1.5 h. By the experimental design, it was found that the variable that most influenced the ester content was late the percentage of catalyst. By physico-chemical analysis it was observed that the biodiesel produced by the in situ method fell within the rules of the ANP, therefore this technique feasible, because does not require the preliminary stage of oil extraction and achieves high levels of esters
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One of the main impacts to the environment is the water pollution, where the industrial sector is one of the main sources of this problem. In order to search for a solution, the industrial sector is looking forward to new technologies to treat its wastewaters with the goal to reuse the water in the own process. In this mode, the treatment presents a reduction in its costs with the water suply. One of these technologies that are getting more and more applications is the advanced oxidative processes (AOP´s). In this work two industrial wastewaters have been studied, i.e., containing polymers and pharmacus. In the case of the wastewaters with polymers the UV/H2O2 process has been applied with a systematic series of experiments, using irradiation from a mercury lamp and also solar. The following variables of the UV/H2O2 process for the polymers wastewaters have been studied systematically with the lamp reactor: mode of addition of hydrogen peroxide, temperature, time of reaction, hydrogen peroxide concentration and power of the lamp (80, 125, 250 and 400W). The results demonstrated to be satisfactory, obtaining rates of organic charge removal of 100% in 120 minutes of reaction. The studied variables for the experiments with solar irradiation using polymers wastewaters were only the time of reaction, the mode of addition and concentration of the hydrogen peroxide. The results with the solar irradiation demonstrated to be not satisfactory, reaching maximum of 22% of TOC removal in 240 minutes of reaction. This is in accordance with the fact that the solar source has only 5% of low UV irradiation. With respect to the photodegradation of the pharmacus wastewaters, the process UV/H2O2 and photo-Fenton have been applied. As a source of photons, in this case, a mercury UV lamp of 80 W has been used. The studied variables for the experiments with artificial irradiation with the pharmacus wastewaters were: initial concentration of the pollutant, concentration of Fe2+ and time of reaction. The results demonstrated a degree of degradation fairly satisfactory, showing a maximum conversion value of 46% in 120 minutes
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The interdisciplinary nature of Astronomy makes it a field of great potential to explore various scientific concepts. However, studies show a great lack of understanding of fundamental subjects, including models that explain phenomena that mark everyday life, like the phases of the moon. Particularly in the context of distance education, learning of such models can be favored by the use of technologies of information and communication. Among other possibilities, we highlight the importance of digital materials that motivate and expand the forms of representation available about phenomena and models. It is also important, however, that these materials promote the explicitation of student's conceptions, as well as interaction with the most central aspects of the astronomical model for the phenomenon. In this dissertation we present a hypermedia module aimed at learning about the phases of the moon, drawn from an investigation on the difficulties with the subject during an Astronomy course for teaching training at undergraduate level at UFRN. The tests of three semesters of course were analyzed, taking into account also the alternative conceptions reported in the literature in astronomy education. The product makes use of small texts, questions, images and interactive animations. Emphasizes questions about the illumination of the Moon and other bodies, and their relationship to the sun, the perception from different angles of objects illuminated by a single source, the cause of the alternation between day and night, the identification of Moon's orbit around the Earth and the occurrence of the phases as a result of the position of observing it, and the perception of time involved in the phenomenon. The module incorporated considerations obtained from interviews with students in two poles where its given presential support for students of the course, and subjects from different pedagogical contexts. The final form of the material was used in a real situation of learning, as supplementary material for the final test of the discipline. The material was analyzed by 7 students and 4 tutors, among 56 users, in the period in question. Most students considered that the so called "Lunar Module" made a difference in their learning, the animations were considered the most prominent aspect, the images were indicated as stimulating and enlightening, and the text informative and enjoyable. The analysis of learning of these students, observing their responses to issues raised at the last evaluation, suggested gains in key aspects relating to the understanding of the phases, but also indicates more persistent difficulties. The work leads us to conclude that it is important to seek contributions for the training of science teachers making use of new technologies, with attention to the treatment of computer as a complementary resource. The interviews that preceded the use of the module, and the way student has sought the module if with questions and/or previous conflicts - established great difference in the effective contribution of the material, indicating that it should be used with the mediation of teacher or tutor, or via strategies that cause interactions between students. It is desirable that these interactions are associated with the recovery of memories of the subjects about previous observations and models, as well as the stimulus to new observations of phenomena
Resumo:
In this work we consider the use of new technologies fron the Space Science and Astronautical, in the learning process, incorporating technical and conceptions of physics Spatial what can take on the response of some problems what there are a lot insistent in populate the mind of professors and followers regarding agreement of these conceptions into the level Average. Intending to bring another contribution to Physics teaching practice, especially Classical Mechanics, but introducing many introductory concepts from Modern Physics, since this topic is considered of great interest for teachers and students, for it involves high technology. It s advanced manufacturing demand certain processes that make possible the application of those concepts
Resumo:
Currently, several psychological and non-psychological tests can be found in publishes without standardization on procedures set in different psychological areas, like intelligence, emotional states, attitudes, social skills, vocation, preferences and others. The computerized psychological testing is a extension of traditional testing psychological practices. However, it has own psychometrics qualities, either by its matching in a computerized environment or by the extension that can be developed in it. The current research, developed from a necessity to study process of validity and reliability on a computerized test, drew a methodological structure to provide parallel applications in numerous kinds of operational groups, evaluating the influences of the time and approach in the computerization process. This validity refers to normative values groups, reproducibility in computerized applications process and data processing. Not every psychological test can be computerized. Therefore, our need to find a good test, with quality and plausible properties to transform in computerized application, leaded us to use The Millon Personality Inventory, created by Theodore Millon. This Inventory assesses personality according to 12 bipolarities distributed in 24 factors, distributed in categories motivational styles, cognitive targets and interpersonal relations. This instrument doesn t diagnose pathological features, but test normal and non adaptive aspects in human personality, comparing with Theodore Millon theory of personality. In oder to support this research in a Brazilian context in psychological testing, we discuss the theme, evaluating the advantages and disadvantages of such practices. Also we discuss the current forms in computerization of psychological testing and the main specific criteria in this psychometric specialized area of knowledge. The test was on-line, hosted in the site http://www.planetapsi.com, during the years of 2007 and 2008, which was available a questionnaire to describe social characteristics before test. A report was generated from the data entry of each user. An application of this test was conducted in a linear way through a national coverage in all Brazil regions, getting 1508 applications. Were organized nine groups, reaching 180 applications in test and retest subject, where three periods of time and three forms of retests for studies of on-line tests were separated. Parallel to this, we organized multi-application session offline group, 20 subjects who received tests by email. The subjects of this study were generally distributed by the five Brazilian regions, and were noticed about the test via the Internet. The performance application in traditional and on-line tested groups subsidies us to conclude that on-line application provides significantly consistency in all criteria for validity studied and justifies its use. The on-line test results were related not only among themselves but were similar to those data of tests done on pencil and paper (0,82). The retests results demonstrated correlation, between 0,92 and, 1 while multisessions had a good correlation in these comparisons. Moreover, were assessed the adequacy of operational criteria used, such as security, the performance of users, the environmental characteristics, the organization of the database, operational costs and limitations in this on-line inventory. In all these five items, there were excellent performances, concluding, also, that it s possible a self-applied psychometric test. The results of this work are a guide to question and establish of methodologies studies for computerization psychological testing software in the country
Resumo:
The elderly population growth in Brazil and in the world is an incontestable reality, arising from a significant declining rate in mortality and fertility, resulting from the remarkable improvements in the quality of life of the people. Associated with the introduction of new technologies in the medical area, these issues have been highly contributing for the increase of the population longevity. The numbers of the elderly in Brazil and in the world show female population predominance within the aging segment, a phenomenon known as the feminisation of the old-age . Aging, therefore, is nowadays one of the primary issues and that has been mobilizing the Brazilian s society, since the development raised from this new reality brought with it enormous challenges and complex social implications which are already felt in the daily lives of the societies. My work experience among some age groups has shown that aging is a much differentiated process which has instigated my interest in understanding why aging has to face an overwhelming and painful experience for some people and enriched and full of signification for others. Overviewing, this research aimed to understand the aging development through the analysis of the processes of signification and production of meaning that permeate the aging and the subjective well-being of three aged women participants of the Project Health and Citizenship on Third Age /CEFET-RN, that evidenced attitudes and behaviors concerning the integration and the activity toward the elderly population. The methodological strategy used was History of Life, starting from collecting data based on deep interviews. The analysis of data evidenced that the elderly well-being is a unique and distinct meaningful experience for each person, concerning each story of their lives within differentiated social, cultural, economic context, from this perspective one can demystify the concept of that aging occurs in a homogeneous way for everyone, everywhere and with the same rhythm. The narratives presented in this research showed the human development as being a dialectic, discursive and interactionist process which extends throughout the adult life and continues to the aging life. The guarantee that development and aging are a parallel phenomenon always in interdependence on the preceding phases of live, are corroborated within the studies. This present study confirms that the elderly population can be a phase of growth, personal realization and continued development, without disrespecting the heterogeneous and the subjectivity of the person who ages. Notifying those healthy and well-succeeded aging experiences, this issue has the intention to contribute to demystify the concept of aging as a social problem, illness needed to be treated, and the stereotypy of the elderly being dependent and unproductive
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Distributed multimedia systems have highly variable characteristics, resulting in new requirements while new technologies become available or in the need for adequacy in accordance with the amount of available resources. So, these systems should provide support for dynamic adaptations in order to adjust their structures and behaviors at runtime. This paper presents an approach to adaptation model-based and proposes a reflective and component-based framework for construction and support of self-adaptive distributed multimedia systems, providing many facilities for the development and evolution of such systems, such as dynamic adaptation. The propose is to keep one or more models to represent the system at runtime, so some external entity can perform an analysis of these models by identifying problems and trying to solve them. These models integrate the reflective meta-level, acting as a system self-representation. The framework defines a meta-model for description of self-adaptive distributed multimedia applications, which can represent components and their relationships, policies for QoS specification and adaptation actions. Additionally, this paper proposes an ADL and architecture for model-based adaptation. As a case study, this paper presents some scenarios to demonstrate the application of the framework in practice, with and without the use of ADL, as well as check some characteristics related to dynamic adaptation
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This documental research in a qualitative and interpretative nature is inserted in the field of Applied Linguistics and its object of study is teachers‟ writing in a literacy event (public exam) held for teachers of Portuguese Language by municipality in Natal city - RN in 2008. Overall, we have aimed to investigate the textual production of these teachers, considering their knowledge about writing, their sayings in relation to themselves and their views on new technologies and teaching. Specifically, we have chosen the following objectives: a) identifying what knowledge about writing have emerged from teachers' written text; b) analyzing the written text production of teachers, considering the knowledge they have revealed about themselves; c) mapping the sayings of the teachers about the teaching profession and new technologies. Our discussion is grounded theoretically by Bakhtin studies of language (BAKHTIN [1934], 1990; [1952-1953], 2000; BAKHTIN; VOLOSHINOV [1929], 1999); in studies of critical literacy as formulated by STREET (1984, 1995, 2006, 2010, 2014); KLEIMAN (1995, 2005, 2006, 2008); (BARTON, HAMILTON, 1998; BARTON; Ivanic, 1991); studies on teacher training in critical educational perspective (GIROUX, 1986; 1987; 1997; 1999) FREIRE, 1999; 2001). The corpus of this study is consisted of written texts by participants of this examination about the Writing Test, in which they were asked to produce an opinion paper. The research has allowed us to realize that, in relation to the writing, despite the recurring negative discourse on literacy teachers, especially the Portuguese ones, these, in the fabric of their texts, both have revealed to have dominion over the formal structure, particularly in respect to prototypical schema of argumentative sequence, as proposed by Adam (1992, 2008) and the mechanisms of textualization postulated by Bronckart (2007), and on those enunciation-discursive strategies relating to opinion genre. The relevance of this research is justified by seeking to understand the teacher‟s writing beyond the language system, i.e, writing as speech, assuming it as a contrapalavra (BAKHTIN, [1934], 1990) to those voices that insist on underestimating literacy teachers and they do so much harm to society, to the extent that foster a sense of disbelief in the qualification of teachers' work and distrust of the social role of these professionals in the preparation of future generations
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The advancement of nanotechnology in the synthesis and characterisation of nanoparticles (NP's) has played an important role in the development of new technologies for various applications of nano-scale materials that have unique properties. The scientific development in the last decades in the field of nanotechnology has sought ceaselessly, the discovery of new materials for the most diverse applications, such as biomedical areas, chemical, optical, mechanical and textiles. The high bactericidal efficiency of metallic nanoparticles (Au and Ag), among other metals is well known, due to its ability to act in the DNA of fungi, viruses and bacteria, interrupting the process of cellular respiration, making them important means of study, in addition to its ability to protect UVA and UVB. The present work has as its main objective the implementation of an innovative method in the impregnation of nanoparticles of gold in textile substrate, functionalized with chitosan, by a dyeing process by exhaustion, with the control of temperature, time and velocity, thus obtaining microbial characteristics and UV protection. The exhausted substrates with colloidal solutions of NPAu's presented the colours, lilac and red (soybean knits) due to their surface plasmon peak around 520-540 nm. The NPAu's were synthesized chemically, using sodium citrate as a reducing agent and stabilizer. The material was previously cationised with chitosan, a natural polyelectrolyte, with the purpose of functionalising it to enhance the adsorption of colloid, at concentrations of 5, 7, 10 and 20 % of the bonding agent on the weight of the material (OWM). It was also observed, through an experimental design 23 , with 3 central points, which was the best process of exhaustion of the substrates, using the following factors: Time (min.), temperature (OC) and concentration of the colloid (%), having as a response to variable K/S (ABSORBÂNCIA/ Kubelka-Munk) of the fibres. Furthermore, it was evidenced as the best response, the following parameters: concentration 100%, temperature 70 ºC and time 30 minutes. The substrate with NPAu was characterised by XRD; thermal analysis using TGA; microstructural study using SEM/EDS and STEM, thus showing the NP on the surface of the substrate confirming the presence of the metal. The substrates showed higher washing fastness, antibacterial properties and UV radiation protection.
Resumo:
The recognition of the food as determinant and health-disease process etching requires new explanations and interventions of the food and nutrition policy action and demand health care model based on the completeness of the actions and focused on health promotion. This study, characterized as research-action of interventionist character, sought to develop strategies to support the transverse insertion of healthy eating promotion in professionals practices a core of support for the health of the family and a family health strategy Unit in the city of Natal, capital of Rio Grande do Norte, from the analysis of perceptions and work processes of these teams. Several methodological strategies were adopted: Dialectical Hermeneutical Circle, direct observation, reflective and Thematic Meetings Workshop "Rethinking the educational practices for promoting healthy eating". For data logging, search diaries - SD were used and moments. The analysis of procedural form occurred in conjunction with research participants, in constant movement of reflection-action-reflection, based on hermeneutics-dialectic. About the results, in relation to the promotion of health, showed the following insights: health promotion and disease prevention-related harms; health promotion related to quality of life and well-being, in its various dimensions; health promotion as a responsibility of the State; health promotion related to the actions of health education; health promotion as an expression of efficaciousness and accessibility to health services. Regarding healthy nutrition, predominated the perceptions relating to nutritional aspects. With regard to food and nutritional education - FNE, it was observed a predominance of perception of FNE as information, guidance and knowledge transfer for changes of dietary practices. As regards the working process, it was observed that among the actions for health promotion, educational activities predominate, such as lectures, conversations, groups that mostly occur in fragmentary form, without joint planning teams, varying according to the professionals and the moment of work in which they are carried out. The results pointed to the need for reorganization of the work processes, in the context of intra-and intersectoral coordination and the construction of new technologies, such as: Health project of the territory – HPT, Unique Therapeutic Project- UPT, Expanded Clinic and educational practices, Shared with active teaching and learning methodologies. From the results we believe that it is necessary to "thought reform", from changes in vocational training and strengthening of the permanent education spaces, whereas the complexity that involves feeding, food and nutrition education and health promotion. The reformation of thought must be articulate and closely tied to the production of knowledge and practices that encourage intersectoral approach, the transversality, dialogue and democratic and supportive attitude, based on the collective construction of know-how. We hope that this study can contribute with reflections and initiatives that encourage building practices that promote healthy eating in primary health care, in terms of completeness of the care and the attainment of food security and nutrition.