5 resultados para Relative complexity

em Universidade Federal do Rio Grande do Norte(UFRN)


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Frequency Selective Surfaces (FSS) are periodic structures in one or two dimensions that act as spatial filters, can be formed by elements of type conductors patches or apertures, functioning as filters band-stop or band-pass respectively. The interest in the study of FSS has grown through the years, because such structures meet specific requirements as low-cost, reduced dimensions and weighs, beyond the possibility to integrate with other microwave circuits. The most varied applications for such structures have been investigated, as for example, radomes, antennas systems for airplanes, electromagnetic filters for reflective antennas, absorbers structures, etc. Several methods have been used for the analysis of FSS, among them, the Wave Method (WCIP). Are various shapes of elements that can be used in FSS, as for example, fractal type, which presents a relative geometric complexity. This work has as main objective to propose a simplification geometric procedure a fractal FSS, from the analysis of influence of details (gaps) of geometry of the same in behavior of the resonance frequency. Complementarily is shown a simple method to adjust the frequency resonance through analysis of a FSS, which uses a square basic cell, in which are inserted two reentrance and dimensions these reentrance are varied, making it possible to adjust the frequency. For this, the structures are analyzed numerically, using WCIP, and later are characterized experimentally comparing the results obtained. For the two cases is evaluated, the influence of electric and magnetic fields, the latter through the electric current density vector. Is realized a bibliographic study about the theme and are presented suggestions for the continuation of this work

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The petroleum industry, in consequence of an intense activity of exploration and production, is responsible by great part of the generation of residues, which are considered toxic and pollutants to the environment. Among these, the oil sludge is found produced during the production, transportation and refine phases. This work had the purpose to develop a process to recovery the oil present in oil sludge, in order to use the recovered oil as fuel or return it to the refining plant. From the preliminary tests, were identified the most important independent variables, like: temperature, contact time, solvents and acid volumes. Initially, a series of parameters to characterize the oil sludge was determined to characterize its. A special extractor was projected to work with oily waste. Two experimental designs were applied: fractional factorial and Doehlert. The tests were carried out in batch process to the conditions of the experimental designs applied. The efficiency obtained in the oil extraction process was 70%, in average. Oil sludge is composed of 36,2% of oil, 16,8% of ash, 40% of water and 7% of volatile constituents. However, the statistical analysis showed that the quadratic model was not well fitted to the process with a relative low determination coefficient (60,6%). This occurred due to the complexity of the oil sludge. To obtain a model able to represent the experiments, the mathematical model was used, the so called artificial neural networks (RNA), which was generated, initially, with 2, 4, 5, 6, 7 and 8 neurons in the hidden layer, 64 experimental results and 10000 presentations (interactions). Lesser dispersions were verified between the experimental and calculated values using 4 neurons, regarding the proportion of experimental points and estimated parameters. The analysis of the average deviations of the test divided by the respective training showed up that 2150 presentations resulted in the best value parameters. For the new model, the determination coefficient was 87,5%, which is quite satisfactory for the studied system

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The gray mold, causal organism Amphobotrys ricini, is one of the major diseases of castor bean. Difficulties in managing plant disease arises form the limited understanding of the genetic structure of A. ricini, their complexity and variability make it difficult to control. Genetic structure can be used to infer the relative impact of different forces that influence the evolution of pathogen populations, that allow to predict the potencial for pathogen populations to envolve in agricultural ecosystems. Growers protect their crop by applying fungicides, but there aren t fungicides to provide significant control of gray mold of castor bean. The objectives of this work were use RAPD to determine the genetic structure of A. ricini subpopulations in Paraíba and assay the sensitivity of A. ricini isolates to azoxystrobin and carbendazim. To determine the genetic structure of A. ricini subpopulations in Paraíba, 23 isolates were colleted from two different geographic location (subpopulation). These isolates were analysed by RAPD using 22 random decamer primers, purchased from OPERON, produced a total of 80 markers polimorphics. The resulting matrixes were analysed using PopGene version 1.32. Sensitivity to azoxystrobin and carbendazim of 30 isolates, colleted form Paraíba and Alagoas, was estimated based on spore germination and colony growth inhibition. The stock solutions were added toV8 medium after sterilization to produce final concentrations of 0, 0.01, 0.1, 1, 10, and 100 µg/ml of carbendazim and 0, 0.001, 0.01, 0.1, 1, and 10 µg/ml of azoxystrobin. All statistical analyses were performed using SAS to estimate the dose that inhibited fungal growth by 50% (ED50 values). The genetic diversity within subpopulations (Hs=0,271) accounted for 92% of the total genetic diversity (Ht=0,293), while genetic diversity between subpopulations (Gst = 0,075) represented only 7,5%. The estimated number of migrants per generation (NM ) was 6,15. Nei s average gene identity across 80 RAPD loci was 0,9468. Individual ED50 values, for the 30 isolates screened for their sensitivity to azoxystrobin, ranged From a maximum of 0,168 µg/ml to a minimum of 0,0036 µg/ml. The ED50 values for carbendazim varied within the range of 0,026 to 0,316 µg/ml

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Systemic lupus erythematous (SLE) is a chronic and auto-immune disease that can affect several systems of one´s body, including the nervous system, causing several clinical evidences, which can put in risk the person´s life. Although the illness could manifest itself at any age or sex, studies indicate higher incidence among women. Its etiology points to the combination of genetic, hormonal and environmental factors. Due to the disease´s complexity, it is evident that it affects all the person´s life as a whole and not only its organic dimension. It is believed that the signification attributed to all the process of sickening influences its treatment, as well as the person´s capacity to cope with the difficulties and implicit profits involved in the process.In this study, eight women who were affected by SLE were interviewed, with the aim of examining carefully the processes of signification as well as the generation of meanings which permeate these women´s sickening processes. The analysis of their speeches evidences distinct forms of giving meaning to the process, regardless of the time of the diagnosis. The fact that the disease is incurable was shocking to all the participants, and it demanded changes in their lives, in order to detain a relative control of their condition. The majority of the participants were able to deal with these modifications, since strategies have been created to face the difficulties and thus to preserve their social life, without damaging their health. However, some of the participants did not obtain strenght to cope with the disease, eventually developing a depressive state. It is observed that not only SLE has innumerable ways of manifestation, but the experience of the illness is very subjective and dynamic. There are also several ways of expressing this experience, according to the implications in the social, cultural and economic context where the participants are inserted. This ratifies the necessity of a interdisciplinary approach to embrace SLE complexity. (310 words, 1.610 characters)

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Our professional everyday life, as a psychologist, we often come across the narrative made by women of a permanent suffering experience in loving and sexual relation. This checking created questions which indicated to the questioned experience singularity, taking into account the historic and cultural aspects (genre and romantic love) that seemed to permeate such an experience. The conduction given to this research was guided by the following question: how is to the woman the experience of going on suffering on loving and sexual relation? Therefore, the objective was to understand that experience. Were carried out with six women that were living the experience which intend to investigate. The narrative, in according to the purposal by Walter Benjamin was the access tool to the experience. The narrative analysis shows the singularity of constant suffering experience on loving relation as well as common aspects. It is remarkable the presence of relative questions to the genre and romantic loving dimension, influencing the way as the interviewed women perceive themselves on the existence and realize the loving suffering which experience. Women reveal several ways of expressing and perceiving to the loving suffering which is common the manifestation of several physical and psychic symptoms. The most participants had experiences of protected familiar contact of feeling development of low self-esteem, disability, unstableness and fear. We realize that the suffering of interviewed women, on loving relation, it revels, above all, a way of being in the world, perveiving themselves, marked by solitude fear, lovelessness, leading the life itself giving origin to the lifestyle and of really new loving. Thus, we emphasize the importance of greater engagement of professionals and institutions which deal with the thematic this research in order to develop actions that consider its complexity. We also emphasize new reflections about the loving suffering so that different sense possibilities can emerge propitiating a greater comprehension of human subjectivity