54 resultados para Auto-referência


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This paper presents an evaluative study about the effects of using a machine learning technique on the main features of a self-organizing and multiobjective genetic algorithm (GA). A typical GA can be seen as a search technique which is usually applied in problems involving no polynomial complexity. Originally, these algorithms were designed to create methods that seek acceptable solutions to problems where the global optimum is inaccessible or difficult to obtain. At first, the GAs considered only one evaluation function and a single objective optimization. Today, however, implementations that consider several optimization objectives simultaneously (multiobjective algorithms) are common, besides allowing the change of many components of the algorithm dynamically (self-organizing algorithms). At the same time, they are also common combinations of GAs with machine learning techniques to improve some of its characteristics of performance and use. In this work, a GA with a machine learning technique was analyzed and applied in a antenna design. We used a variant of bicubic interpolation technique, called 2D Spline, as machine learning technique to estimate the behavior of a dynamic fitness function, based on the knowledge obtained from a set of laboratory experiments. This fitness function is also called evaluation function and, it is responsible for determining the fitness degree of a candidate solution (individual), in relation to others in the same population. The algorithm can be applied in many areas, including in the field of telecommunications, as projects of antennas and frequency selective surfaces. In this particular work, the presented algorithm was developed to optimize the design of a microstrip antenna, usually used in wireless communication systems for application in Ultra-Wideband (UWB). The algorithm allowed the optimization of two variables of geometry antenna - the length (Ls) and width (Ws) a slit in the ground plane with respect to three objectives: radiated signal bandwidth, return loss and central frequency deviation. These two dimensions (Ws and Ls) are used as variables in three different interpolation functions, one Spline for each optimization objective, to compose a multiobjective and aggregate fitness function. The final result proposed by the algorithm was compared with the simulation program result and the measured result of a physical prototype of the antenna built in the laboratory. In the present study, the algorithm was analyzed with respect to their success degree in relation to four important characteristics of a self-organizing multiobjective GA: performance, flexibility, scalability and accuracy. At the end of the study, it was observed a time increase in algorithm execution in comparison to a common GA, due to the time required for the machine learning process. On the plus side, we notice a sensitive gain with respect to flexibility and accuracy of results, and a prosperous path that indicates directions to the algorithm to allow the optimization problems with "η" variables

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Self-organizing maps (SOM) are artificial neural networks widely used in the data mining field, mainly because they constitute a dimensionality reduction technique given the fixed grid of neurons associated with the network. In order to properly the partition and visualize the SOM network, the various methods available in the literature must be applied in a post-processing stage, that consists of inferring, through its neurons, relevant characteristics of the data set. In general, such processing applied to the network neurons, instead of the entire database, reduces the computational costs due to vector quantization. This work proposes a post-processing of the SOM neurons in the input and output spaces, combining visualization techniques with algorithms based on gravitational forces and the search for the shortest path with the greatest reward. Such methods take into account the connection strength between neighbouring neurons and characteristics of pattern density and distances among neurons, both associated with the position that the neurons occupy in the data space after training the network. Thus, the goal consists of defining more clearly the arrangement of the clusters present in the data. Experiments were carried out so as to evaluate the proposed methods using various artificially generated data sets, as well as real world data sets. The results obtained were compared with those from a number of well-known methods existent in the literature

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In this study we investigate the reference to other s discourse done it through the resource of direct cited discourse at background section in monographic texts produced by university students at the last phase of final work in their graduate Letras course. This work is guided in cited/related discourse studies in Bakhtin (2004), Authier-Revuz (1990, 1998, 2004), Maingueneau (1996, 2002), Charaudeau and Maingueneau (2004); in genre approaches developed by Bakhtin (2000); Maingueneau (1996, 2002); socio-discursive interaction (BRONCKART, 1999, 2003; SCHNEUWLY, 2004; DOLZ e SCHNEUWLY, 2004) and Bazerman (2005); and also in presuppositions of Textual Linguistics presented by Charrolles (1988), Van Dijk (1997), Beaugrande and Dressier (1981), Koch and Travaglia (1993, 1995), Koch (2002, 2004) and Val (2000, 2004). We have established as aims to analyze and interpret meaning relations problems in how to articulate direct cited discourse with citing discourse and at the same time explain semantic implications that comes from that articulation that compromise text meaning, at background section in that monographic genre. The analysis, by qualitative and quantitative basis in eleven monographic works that form our corpus, gave us the opportunity to achieve and see that meaning relationships in the articulation of direct cited discourse with citing discourse show problems that may be categorized into three different groups: problems related to meaning relationships with citing discourse that comes before it, problems of meaning relationships with citing discourse that comes after it, and problems with of meaning relationships with citing discourse that come before it and at the same time with citing discourse that comes after it (i.e. in relation to both). These analysis also allow us assert that, these problems, just because they occur frequently, they affect the micro level text coherence, and they also compromise the text global meaning. The results show that students at Letras Course, even in the ending process of their course do not show the real domain in relation to some ways of direct cited discourse organization and working, and also how the ideas articulation work in the construction of relations between direct cited discourse and the citing discourse that can turn those students able to produce a text that enhance acceptable patterns

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This dissertation, entitled O Auto da Morte e da Vida: A escrita barroca de João Cabral de Melo Neto, has the aim of analising, interpreting, in a baroque perspective, Cabral s writing in the poem/play Morte e vida severina Auto de Natal Pernambucano, taking as basis the theories of Eugênio D´Ors, Severo Sarduy, Omar Calabrase, Lezama Lima, Afonso Ávila, Affonso Romano de Sant´Anna and others cited in the body of this work. During the analisys we feature confluences, relations, similarities, identification between the Baroque of the counter reformation and the modern Baroque or Neobaroque. We seek to comprehend the baroque which is new in the XX century and Cabral s poetry as an element of the contemporaneity, by updating the concept of the Baroque in the 1600s, when it is detected in its purest characteristic in human relation (the life of the Northwestern brazilian) through an intangible reality (the death). The Baroque as a cultural summary of a period of instability and transformation, with the power of dismantling an already established poetry. The fight between words and things, language and reality

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Beneath the theoretical assumptions of Cognitive Linguistics contemporary, we analyze the cognitive processes underlying the construction of the reference in the text. To do so, we choose as corpus the written textual productions of undergraduates at the Department of Distance Education/UFRN provided in sections of responses of presential evaluation activities and activities in the Moodle virtual ambience. These activities and texts were produced in the discipline of Reading, Interpretation and Textual Production taught in the courses of Chemistry, Physics, Mathematics, Biology and Geography we monitor during the period of 2008.1 to 2010.1. Through the analysis of discursive productions, it was evident that the construction of the reference is made by means of the activation and manipulation of information acquired through our perceptual and social experiences. Thus, we confirm the cognitive assumption that the linguistic clues available in the texts of the activities serve as guides towards cognitive domains that activate the process of building reference

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Los cambios sociales y culturales que caracterizan el mundo contemporáneo sorprendieron estudiosos de todas las áreas. Los avances tecnológicos principalmente en el área de transmisión de informaciones revolucionaron las nociones de tiempo y espacio. Nuevos medios de comunicación, favorecidos principalmente por la llegada de Internet, abrieron espacios de expresión para ciudadanos deseosos de ser oídos. Aún coexistiendo con los medios de comunicación tradicionales, los nuevos espacios representan una oportunidad de libertad de expresión, de interacción sin mediaciones y de construcción de contenidos independientes. Movimientos sociales se organizan a través de estos nuevos medios de comunicación y desarrollan un activismo que comienza en forma virtual y se extiende a movilizaciones presenciales. Castells (2009) llama de auto comunicación de masas a ese proceso de producir y difundir informaciones que antes era propiedad exclusiva de los medios de comunicación tradicionales. Natal, fue escenario de la gestación y articulación virtual de un movimiento denominado Fora Micarla cuyo objetivo ha sido lograr el impeachment de la alcaldesa de la ciudad, Micarla de Souza. Aunque el objetivo principal no fue alcanzado, el movimiento formó parte de los procesos de cambio social que llevaron los ciudadanos al ciberactivismo. El Fora Micarla se constituye también como un cambio social en sí mismo al colaborar en la consolidación de la identidad colectiva de un grupo de jóvenes universitarios en busca de justicia social. El Twitter fue el principal canal de expresión del grupo y responsable por la rápida expansión de las movilizaciones. El Abordaje Sociológico y Comunicacional del Discurso (ASCD) ha aportado el marco teórico de referencia utilizado en esta investigación. La Comunicación para el Cambio Social (GUMUCIO, 2008) y la Sociología Aplicada al Cambio Social (SACO, 2006) así como los estudios del sujeto y de las identidades (BAJOIT, 2006) forman la base de la ASCD para un estudio más completo de las prácticas discursivas. Considerando que el objeto de estudio son las manifestaciones discursivas de los usuarios simpatizantes del Movimiento Fora Micarla , y que la ASCD es un brazo del Análisis Crítico del Discurso, se hace necesario un análisis lingüístico de los textos. La Gramática Sistémica Funcional, a través del Sistema de Evaluación desarrollado por Martin and White (2004), ofrece los recursos para evaluar las manifestaciones por medio de tuítes de los integrantes del movimiento. La representación de los actores sociales (VAN LEUWEEN, 1998) complementa el análisis discursivo crítico de la ASCD. El empoderamiento ciudadano se materializa por medio de los cambios conquistados a través de los nuevos medios

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This study approach the Jorge Luis Borges s prose of fiction under the perspective of mimesis and the self-reflexivity. The hypothesis is that the Aleph is a central symbol of the Borges s fictional universe. The rewriting and the retake of this symbol along of his work entail to a reflection about the possibilities and the limits of mimesis. This study is divided in three parts which contain two chapters. The first part Bibliographic revision and conceptual fundaments of inquiry discuss the critical fortune of author (Chapter 1) and the concepts that will give sustentation to the inquiry (Chapter 2). The second part About the Borges s aesthetic project sketch out the literary project defended by Borges that is his conception of the literature and his ideological matrix (Chapter 3) beside his anti-psychologism and his nostalgia of epos (Chapter 4). The third and last part is entitled The Aleph and his doubles. In the chapter 5 this study analyses the short story El Aleph and consider its centrality on the Borges s work. The argument that is on this short story Borges elaborates a reflection about mimesis. In the chapter 6, on the same hand, four short stories will be analysed: Funes el memorioso ; El Libro de Arena ; El evangelio según Marcos and Del rigor en la ciencia . The conclusion that is the Borges s literature is self-awake of its process as such demonstrate its parodic sense and its bookish origin. Hence, the Borges s literature overlapping the mimetic crisis of language and challenge the limits between fiction and reality. However, it doesn t surrender to the nihilist perspective that is closing of literature to the world

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This work is a detailed study of self-similar models for the expansion of extragalactic radio sources. A review is made of the definitions of AGN, the unified model is discussed and the main characteristics of double radio sources are examined. Three classification schemes are outlined and the self-similar models found in the literature are studied in detail. A self-similar model is proposed that represents a generalization of the models found in the literature. In this model, the area of the head of the jet varies with the size of the jet with a power law with an exponent γ. The atmosphere has a variable density that may or may not be spherically symmetric and it is taken into account the time variation of the cinematic luminosity of the jet according to a power law with an exponent h. It is possible to show that models Type I, II and III are particular cases of the general model and one also discusses the evolution of the sources radio luminosity. One compares the evolutionary curves of the general model with the particular cases and with the observational data in a P-D diagram. The results show that the model allows a better agreement with the observations depending on the appropriate choice of the model parameters.

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The strength of respiratory muscle are frequently assessed by maximal inspiratory and expiratory pressure, however, the maneuvers to assess PImax and PEmax are difficult for many patients. The sniff nasal inspiratory pressure (SNIP) is a simple and noninvasive technique use to assess inspiratory muscles strength. Reference values have been previous established for SNIP in adults but no previous studies have provided reference values for SNIP in adult Brazilian population. The main objective of this study were propose reference values of SNIP for Brazilian population through establishment of relationship between anthropometric measurements, physical activity profile and SNIP and at the same time compare the values obtained with reference values previously published. We studied 117 subjects (59 male and 58 female) distributed in different age grouped 20-80 years old. The results showed on significant positive relationship between SNIP and height and negative correlation with age (p<0.05). In the multiple linear regression analysis only age continued to have an independent predictive role for the two dependent variables that correlated with SNIP. The values of SNIP found in Brazilian population were higher when compared with predict values of previous studies. The results of this study provide reference equations of SNIP for health Brazilian population from 20 to 80 years old

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The aging process modifies various systems in the body, leading to changes in mobility, balance and muscle strength. This can cause a drop in the elderly, or not changing the perceived self-efficacy in preventing falls. Objective: To compare the mobility, body balance and muscle performance according to self-efficacy for falls in community-dwelling elderly. Methods: A cross-sectional comparative study with 63 older (65-80 years) community. Were evaluated for identification data and sociodemographic, cognitive screening using the Mini Mental State Examination (MMSE), effective for the fall of Falls Efficacy Scale International Brazil (FES-I-BRAZIL), Mobility through the Timed Up and Go Test , the balance Berg Balance Scale (BBS) and the Modified Clinical Test tests of Sensory Interaction on Balance (mCTSIB), tandem walk (TW) and Sit to Stand (STS) of the Balance Master® System. Finally, muscle performance by using isokinetic dynamometry. Statistical analysis was performed Student t test for comparison between groups, with p value ≤ 0.05. Results: Comparing the elderly with low-efficacy for falls with high-efficacy for falls, we found significant differences only for the variable Timed Up and Go Test (p = 0.04). With regard to data on balance tests were significant differences in the speed of oscillation firm surface eyes open modified Clinical Test of Sensory Interaction on Test of Balance (p = 0.01). Variables to isokinetic dynamometry were no significant differences in movement knee extension, as regards the variables peak torque (p = 0.04) and power (p = 0.03). Conclusion: The results suggest that, compared to older community with low-and high-efficacy for falls, we observed differences in variables related to mobility, balance and muscle function

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

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Marmosets, Callithrix jacchus, are strictly diurnal animals. The motor activity rhythmicity is generated by the circadian timing system and is modulated by environmental factors, mainly by photic stimuli that compose the light-dark cycle. Photic stimuli can reset the biological oscilators changing activity motor pattern, by a mechanism called entrainment. Otherwise, light can act directly on expressed rhythm, without act on the biological oscillators, promoting the masking. Thus, photic stimuli can synchronize the circadian activity rhythm (CAR) by two distinct mechanisms, acting isolated or at a combined way. Among the elements that can influence photic synchronization, the duration and time of photic exposure is pointed out. If in the natural environment the marmoset can choose places of different intensity illumination and is synchronized to light-dark cycle (LD), how the photic synchronization mechanism can be evaluated in laboratory by light self-selection? With objective to response this question, four adult male marmosets were studied at two conditions: with and without sleeping box. The animals were submitted to a LD cycle (12:12/ 350:2 lx) and constant light (LL: 350 lx) conditions in individual cages with an opaque sleeping box, that permitted the light self-selection. At the room, the temperature was 25.6 ºC (± 0.3 ºC) and humidity was 78.7 (± 5%). The motor activity was recorded at 5 min bins by infrared movement sensors installed at the top of the cages. The motor activity profile was distinct at the two conditions: without the sleeping box protection against light, the activity frequency was higher at CT 11-12 (ANOVA; F(3.23) = 62.27; p < 0.01). Also, the duration of the active phase (α) was prolonged of about 1 h (t test, p < 0.05) and the animals showed a significant delay on the activity onset and offset (t test, p < 0.05) and at the acrophase (confidence intervals of 5%) of CAR. In LL, the light continuous exposure prolonged the active phase and influenced the endogenous expression of the circadian activity rhythm period. From the result analysis, it is concluded that the light self-selection can modify several parameters of CAR in marmosets, allowing the study of the synchronization mechanism using the burrow model. Thus, without sleeping box there was a phase delay between the CAR and LD (entrainment) and an increase of activity near lights off (positive masking). Furthermore, in LL, the light continuous exposure modifies α and the endogenous expression of CAR. It is suggested that the light self-selection might be take into account at investigations that evaluate the biological rhythmicity in marmosets

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This research investigates the self-esteem of children who suffered physical violence by family members. Seven children took part in the research: three boys and four girls, aged between six and twelve years old. The analysis were done from the constructed data obtained from: semi-structured interview, activities about human feelings, activities that included facial expressions, unfinished phrases, Pinocchio s story, a drawing of a family and a drawing of their own family. Data were analyzed from the Content Analysis. The Thematic Units were: violence, intrafamily violence, and self-esteem. The synthesis of the categories studied evidenced that the physical violence and the psychological violence present in the lives of children affect the positive development of their self-concept and, consequently, of their self-esteem. Among the results, we emphasize some negative feelings that are present in children s lives such as fear, a sense of guilt, and sadness, arising out of the situations of violence they have experienced

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This study aimed to apply, thermogravimetriy /derivative Thermogravimetriy (TG/DTG), differential scanning calorimetry (DSC), Differential Thermal Analysis (DTA), to conduct a comparative study on drug reference, generic and whose active principles are similar captopril hydrochlorothiazide, ampicillin, paracetamol, aspirin and mebendazole sold in local pharmacies. Samples of the active ingredients and dosage forms were also characterized by absorption infrared spectroscopy (IR), X-ray diffraction (XRD) and microscopy scanning electron (SEM). The TG / DTG curves showed a general similarity in the thermal behavior of the samples, but also showed the influence of excipients on the thermal stability. The DSC curve of the generic base hydrochlorothiazide showed no peak on the fusion of the drug due to interference of lactose as a diluent, which causes interaction with the active principle causing their degradation before the merger. The DSC curves of the drugs consisting of paracetamol showed reproducibility at the melting point of the active and the other thermal events. The DSC result of binary mixtures involving captopril / magnesium stearate and mebendazole/magnesium stearate showed possible interactions or incompatibilities evidenced by the displacement of the melting point of both drugs. The other mixtures showed no change. The infrared spectra presented were very similar, indicating the presence of functional groups characteristic of the constituents of the samples. The X-ray diffraction showed peaks indicative of crystalline structure of the active ingredients as well as some of the ingredients in the formulation of the drug and the micrographs indicate a general heterogeneity in the size distribution of particles in the samples

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This work demonstrates the results obtained from research on violence against women: an analysis of the work from reference center of the Social Assistance-CREAS, held in the city of Parnamirim/RN from September 2008 extending through the february of 2009. Having as goal to investigate and examine in a longitudinal cut, which specifically covers the period from 2006 to 2007, find out extent the actions taken by the Reference Center Specialized Social Assistance- CREAS, contributed to the change of women who were there, by checking if there was any change in their positions ahead of the violence and if they began to realize how social subjects, able to control their living conditions and interfere in the orientation of social dynamics Have a particular emphasis on the presence of work and schooling or lack of them is also a factor to be allied to the barriers and rules imposed on women in contemporary society. In this study it was found through a qualitative research guided by dialectical and implemented through the use of documentary research, observation, semi-structured interview and an extensive theoretical background on the subject in question that the woman victim of violence is in a complex and contradictory context where there is both the construction and deconstruction of rights, a view that there are strong influences of patriarchal culture and the consequences of social issues that specifically searched for the public, focuses on social, economic , political, social and cultural. In this sense, the National Policy to Combat Violence against Women, operated by CREASE Parnamirim, is also reflected in its early stages in the life of these women are to nurture a real chance for these victims of violence, to perceive themselves as social subjects can control their lives and interfere in their own destinies. We want this study to add more knowledge to help and most appropriate intervention in this reality, but without the intention of reaching exhaustion, but to subsidize future studies on the topic of women victims of violence