Estudo comparativo de abordagens de inversão do fator de qualidade Q

Seismic wave dispersion and attenuation studies have become an important tool for lithology and fluid discrimination in hydrocarbon reservoirs. The processes associated to attenuation are complex and are encapsulated in a single quantitative description called quality factor (Q). The present dissertation has the objective of comparing different approaches of Q determination and is divided in two parts. Firstly, we made performance and robustness tests of three different approaches for Q determination in the frequency domain. They are: peak shift, centroid shift and spectral ratio. All these tests were performed in a three-layered model. In the suite of tests performed here, we varied the thickness, Q and inclination of the layers for propagation pulses with central frequency of 30, 40 and 60 Hz. We found that the centroid shift method is produces robust results for the entire suíte of tests. Secondly, we inverted for Q values using the peak and centroid shift methods using an sequential grid search algorithm. In this case, centroid shift method also produced more robust results than the peak shift method, despite being of slower convergence

Antenas de microfita com patch em anel e múltiplas camadas dielétricas anisotrópicas uniaxiais

This work presents an analysis of the annular ring microstrip antennas printed on uniaxial anisotropic substrates and with superstrate.The analysis uses the full-wave formulation by means of the Hertz vector potentials method, in the Hankel transform domain. The definition of the Hertz vector potentials and the application of the appropriate boundary conditions to the structure allow determining the dyadic Green functions, relating the current densities in the conducting patch to the transforms of the tangential electric field components. Galerkin s method is then used to obtain the matrix equation whose nontrivial solution gives the complex resonant frequency of the antenna. From the modeling, it is possible to obtain results for the resonant frequency, bandwidth and quality factor, as a function of several parameters of the antenna, for different configurations. We have considered annular ring microstrip antennas on a single dielectric layer, antennas with two anisotropic dielectric layers, and annular ring microstrip antennas on suspended substrates. Numerical results for the resonant frequency of the these structures printed on isotropic substrates are also presented and compared with those published by other authors, showing a good agreement

Caracterização de superfícies seletivas de freqüência e de antenas fractais para aplicações em redes sem fio

This work aims to investigate the behavior of fractal elements in planar microstrip structures. In particular, microstrip antennas and frequency selective surfaces (FSSs) had changed its conventional elements to fractal shapes. For microstrip antennas, was used as the radiating element of Minkowski fractal. The feeding method used was microstrip line. Some prototypes were built and the analysis revealed the possibility of miniaturization of structures, besides the multiband behavior, provided by the fractal element. In particular, the Minkowski fractal antenna level 3 was used to exploit the multiband feature, enabling simultaneous operation of two commercial tracks (Wi-Fi and WiMAX) regulated by ANATEL. After, we investigated the effect of switches that have been placed on the at the pre-fractal edges of radiating element. For the FSSs, the fractal used to elements of FSSs was Dürer s pentagon. Some prototypes were built and measured. The results showed a multiband behavior of the structure provided by fractal geometry. Then, a parametric analysis allowed the analysis of the variation of periodicity on the electromagnetic behavior of FSS, and its bandwidth and quality factor. For numerical and experimental characterization of the structures discussed was used, respectively, the commercial software Ansoft DesignerTM and a vector network analyzer, Agilent N5230A model

Estudo da variação da periodicidade e do acoplamento entre superfícies seletivas de frequência com elementos fractais e helicoidais em estruturas de multicamadas

This work aims to investigate the behavior of fractal and helical elements structures in planar microstrip. In particular, the frequency selective surfaces (FSSs) had changed its conventional elements to fractal and helical formats. The dielectric substrate used was fiberglass (FR-4) and has a thickness of 1.5 mm, a relative permittivity 4.4 and tangent loss equal to 0.02. For FSSs, was adopting the Dürer’s fractal geometry and helical geometry. To make the measurements, we used two antennas horns in direct line of sight, connected by coaxial cable to the vector network analyzer. Some prototypes were select for built and measured. From preliminary results, it was aimed to find practical applications for structures from the cascading between them. For FSSs with Dürer’s fractal elements was observed behavior provided by the multiband fractal geometry, while the bandwidth has become narrow as the level of iteration fractal increased, making it a more selective frequency with a higher quality factor. A parametric analysis allowed the analysis of the variation of the air layer between them. The cascading between fractal elements structure were considered, presented a tri-band behavior for certain values of the layer of air between them, and find applications in the licensed 2.5GHz band (2.3-2.7) and 3.5GHz band (3.3-3.8). For FSSs with helical elements, six structures were considered, namely H0, H1, H2, H3, H4 and H5. The electromagnetic behavior of them was analyzed separately and cascaded. From preliminary results obtained from the separate analysis of structures, including the cascade, the higher the bandwidth, in that the thickness of the air layer increases. In order to find practical applications for helical structures cascaded, the helical elements structure has been cascaded find applications in the X-band (8.0-12.0) and unlicensed band (5.25-5.85). For numerical and experimental characterization of the structures discussed was used, respectively, the commercial software Ansoft Designer and a vector network analyzer, Agilent N5230A model.

Qualidade de vida no trabalho: o caso de enfermeiros dos Hospitais Públicos Walfredo Gurgel e Santa Catarina

The theoretical foundation of this study addresses the construct Quality of Worklife involving pro-active reading organizations in face to social developments of the working class, which is a challenge to the people s management. In this sense, as a contribution to the studies of quality of worklife (QOWL), this study addresses the quality of lifework of nurses at Walfredo Gurgel and Santa Catarina public hospitals. The goal is to make a diagnosis about the quality of lifework of these employees taking as a basis dimensions and performance indicators shown in the model by Fernandes (1996). The research is characterized by field, in a descriptive way. This survey comprised 75 nurses, with 49 by Walfredo Gurgel hospital and 26 by Santa Catarina one. The data collection was carried out through structured questionnaire. The questions were processed in the software Statistic 6.0, with factor analysis and multiple regressions, after the systematization of data. As a result, the most nurses in hospitals are dissatisfied with the quality of lifework, with the highest incidence in Santa Catarina hospital. The variable occupational health assessment was more negative in the hospital Santa Catarina one, whereas in Walfredo Gurgel, was family assistance. The variable guarantee of employment was more positive assessment in two hospitals without, though, implying in high importance on QOWL of nurses. The factor structure and decision showed greater sensitivity to explain the QOWL of nurses, joining 17 variables from 40 of the model. The factor working conditions, joining 6 variables, showed the second highest sensitivity. The compensation factor, gathering 5 variables, showed the third highest sensitivity while image and health factors showed minor importance

Corpo e Velhice: um estudo da qualidade de vida de idosos da Vila Vicentina Júlia Freire em João Pessoa

The aim of this study was to follow the daily routine of elderly individuals residing at the Vila Vicentina Júlia Freire (VVJF) nursing home in João Pessoa, Brazil, observing and analyzing as much as possible, the way in which they live in a group and how they deal, through personal experiences, with their own body image and with that of others. The results were obtained from information considered relevant, according to the perspectives of the residents themselves, contained in narratives of their history and related to their quality of life. Our interest lays in how they coped with changes in their bodies at old age and adapted to the challenges of this new phase. To obtain this information, with significant expressions, we used the Narrative Interview (NI) as a research tool in order to redeem their life experience and develop an understanding of their impressions about the life experience at the current nursing home. We selected, among the housed, ten subjects - actors - to appear as a sample of the group together. The design of our sample had a hybrid model, combining two types: random sample (probability) and an intentional sample (not probability). After recording transcripts and ensuring that all the subjects showed common interests that were relevant to the group, we chose three categories for analysis as follows: a. the elderly as seen by themselves and by others; b. religiosity as a moral factor; c. intimacy and relationships. Our choice was based on the importance of the theme as a multidisciplinary topic in the quality of life of populations. The subjects, chosen as spokespersons for the VVJF, spoke, among other things, about the way in which they viewed the world, their own body and how they experienced the environment and their fellow residents, in an attitude of reflection and criticism that confirms the lucidity of an old age conditioned to an elderly institution. The method allowed us to investigate our subjects from a multidisciplinary point of view. We suggest other studies in assorted areas of the human sciences, having as principle, man at the center of all our scientific questionings. The paradigm that the elder is, necessarily, unhappy in his sheltered has been, in this job, broken through the testimonies collected, establishing multiple perspectives of the analyzed subjects by their respective narrative records. Involving the participation of researchers with major in Administration, Communication and Law, this study filled, in this aspect, the requirements of the multidisciplinarity of the Program of Pos-Graduation in Health Science

Análise da efetividade do transplante renal na qualidade de vida dos receptores no estado do Rio Grande do Norte

This study was developed with the aim of analyzing the effectiveness of renal transplantation on quality of life of kidney recipients in the Rio Grande do Norte State. This is a descriptive study with longitudinal design, panel type with quantitative approach to data analysis. The Quality of Life (QoL) of chronic disease kidney patients before and after kidney transplantation was assessed by the WHOQOL-bref, The population consisted of patients in pre and post-renal transplantation, the sample had 63 patients older than 18 years. The study was conducted after approval by the Research Ethics Committee of the Onofre Lopes University Hospital, Federal University of Rio Grande do Norte, No. CAAE 0008.0.294.000-10. Data collection was performed at a referral center for renal transplantation in Rio Grande do Norte, from May 2010 to May 2013. Data were analyzed using descriptive statistics and presented in tables and graphs. For statistical analyzes, Microsoft Excel XP and SPSS 15.0 software were used. The tests used were simple variance (ANOVA), t-test, Mann-Whitney and Wilcoxon test to compare means, and Spearman correlations. P values <0.05 were considered significant. The demographic data showed a predominance of people between 18 and 45 years (68.2%) with a mean age of 39.9 years (SD 12.2), male (63.5%), married (58.7%), with children (51.0%). Regarding the education level was observed that 49.2% of participants had completed primary school, and most did not engage in any work activity (90.4%) during the study period. Hemodialysis was the predominant renal replacement therapy (96.8%) and the average waiting time for execution of transplantation was 1.9 years (SD 1.9). Comparison of QoL before and after transplantation showed significant differences in all areas analyzed, demonstrating that kidney transplantation had a positive impact on QoL in chronic renal patients undergoing kidney transplantation. Sociodemographic factors did not influence the quality of life in this group of patients, indicating that transplantation was the main factor to explain the improvement in quality of life. Thus, the alternative hypothesis of the study was accept, that there is a significant difference in quality of life before and after kidney transplant. It is expected that the results of this study may contribute to the development of strategies to encourage organ donation and kidney transplantation process

Efetividade da terapia física descongestiva na cicatrização de úlceras venosas

Universidade Federal do Rio Grande do Norte

Qualidade de vida medida pelo "WHOQOL-bref": estudo comparativo de pacientes em hemodiálise e pós-transplante renal

Exploratory descriptive study, prospective with quantitative approach, performed in the nefrology outpatient service from the Onofre Lopes University Hospital (HUOL), Natal/RN, aiming to identify aspects that concern Quality of Life (QOL) on transplanted and hemodialysis patients, as measured by WHOQOL-bref and describe the aspects that differentiate QL between the two groups as measured by the same instrument. The population was of 62 renal patients in hemodialysis and 58 transplantd, with data collected from february to march 2006. The instrument used was WHOQOL-bref, translated to and validated for Portuguese by the multicentric group of the World Health Organization (WHO) in Brazil. The results show predominance of the masculine gender both in the post-transplant group (55,17%), as well as in the hemodialysis group (51,61%); the age strip of 28 to 43 prevailed, among which were 53,45% transplanted and 48,99% hemodialysis patients; 79,93% of the hemodialysis patients and 62,07% of the transplanted were provenient from ouside the capital of the state; from the hemodialysis population, 59,68% were married, while among the transplanted 48,28% were single; 58,06% of the hemodialisys patients had 1 to 3 children, while the majority of the transplanted, 44,83%, had no children; regarding scholarity level on both groups, there was a predominance of incomplete fundamental school, representing 62,9% of the hemodialysis patients and 46,6% of the transplanted; regarding work status, 98,39% of those in hemodialysis informed not to be working, and the same applied to the transplanted, with 75,86%; regarding treatment time, most patients of both populations were in the 1- to 4-year interval, of which were 62,9% of the hemodialisys patients and 53,45% of the transplanted. The analysis of WHOQOL-bref reliability through Crobach s Alpha coefficient had a value of 0,8816, demonstrating good internal consistency for the instrument. Regarding description of QOL tests, the average scores of the post-transplant were (Q-1) 18,14 e (Q-2) 18,69, and 12,3 (Q-1) and 11,29 (Q-2) for the group in hemodialisys. Regarding the aspects that differentiate QOL on the two groups observed through average scores from the Domains: Physical, 15,91 for the post-transplant group and 12,71 for the hemodialisys group; Psychological, 16,75 for the post-transplant group and 14,84 for the hemodialisys group; Social Relations, 17,79 on the post-transplant group and 16,58 on the hemodialisys group; Environment, 14,16 on the post-transplant group and 12,38 on the hemodialisys group. On every evaluated item, the post-transplant group achieved higher scores when compared to the hemodialisys group. The diference in QOL for both populations was significant on all items evaluated with a p<0,005

Fatores da qualidade e satisfação na compra pela internet e sua influência na fidelidade dos consumidores

A presente pesquisa objetivou estudar as relações entre os fatores intervenientes para a satisfação no processo de compras baseadas na Internet e sua influência na fidelidade online (e-loyalty), na visão dos consumidores de varejo virtual. Para tanto, foi utilizado como instrumento de coleta de dados um questionário baseado em fatores de qualidade e fidelidade oriundos dos serviços convencionais, que foi adaptado para a realidade dos serviços digitais. A pesquisa caracteriza-se como exploratória, de natureza quantiqualitativa. A análise quantitativa descreveu e testou a relação de variáveis de qualidade do site e de preço dos produtos do site com as variáveis de satisfação. Neste caso, foram utilizadas técnicas estatísticas como distribuição de freqüência, médias e desvio-padrão e correlação de postos de Spearman. Já na abordagem qualitativa, foi empregada a análise de conteúdo para uma questão aberta relacionada com a identificação dos fatores que levam a fidelidade digital. A pesquisa de campo foi feita com uma amostra de 44 alunos de pós-graduação em nível de Especialização da Universidade Federal do Rio Grande do Norte. Os resultados da análise quantitativa evidenciaram que a qualidade está ligada à satisfação dos clientes em vários fatores, mas o preço não influencia muito na satisfação. Na análise qualitativa, a segurança do website e os preços oferecidos são fatores que potencialmente fidelizam os clientes digitais, segundo a perspectiva dos entrevistados. O fator segurança e confiança no website foi considerado o mais crítico para a fidelidade dos clientes que compram pela Internet

Relacionamentos cooperativos como fator de sustentabilidade na economia solidária no RN: um estudo de caso múltiplo no setor apícola

We are observing, particurlarly in the last two decades an aggravation of social problems inherent in contemporary society, such as high rates of unereloyment and social exclusion. In this context, the social economy appears as an alternative to generate employment and income, especially for the country man through the production and distribution of developed products in a collective way where the actions of cooperation gain significant importance this study aims to determine how the collective actions affect the sustainability of cooperative socio-political and economic developments of the economy and so it was adopted a methodology of multiple case study in three organizations in the apiculture sector of Rio Grande do Norte the Beekeepers Association of São Rafael City (AAMSR); Beekeepers Association of Serra do Mel (APISMEL) and Family Agriculture Cooperative of Apodi (COOAFAP). To evaluate relationship in collaborative ventures solidarity it is constructed a matrix that identify and develop relationship in the organization and, to measure the level of sustainability of these ventures are calculated the indices of socio-political sustainability and economic sustainability. The research results shows a fully collaborative relationship in all cases based on factors such as effective communication between beekeepers involved/and also cooperated with these organization; availability of beekeepers to perform adjustments in production process; an organizational culture focused on collaboration and high level of situation described above and taking into account that the business of solidarity economy better positioned in the matrix of relationships are those that have best indices of sustainability, it is evidence the importance of collaborative relationships for the sustainability of joint ventures

Egressos na avaliação da qualidade de um curso: o caso da Engenharia de Produção da UFRN

This thesis aims at analyzing the perspective of graduates perceived quality of an undergraduate course in order to contribute to continuous improvement. In order to achieve the proposed objectives, we performed a literature search, seeking together the work surrounding this issue, with the intent to update the concepts discussed today on the subject studied, they are: quality management, quality in higher education institutions and the system national assessment of higher education - Sinaes. The methodology is characterized as a case study, quantitative, and the object of study is composed of students who graduated from Production Engineering, Federal University of Rio Grande do Norte, which includes students who graduated from 2002 to 2010; data collection was done through the survey instrument, questionnaire, available online through SurveyMonkey interface, data analysis was done by means of descriptive statistics and multivariate analysis, including factor analysis. The proposed survey instrument consists of questions nineteen and twenty statements that address the central theme of this dissertation. The results show the identification of four latent factors (obtained by exploratory factor analysis), through two perspectives, the analysis of perception and importance, the results were similar in terms of the variable factors. The first factor was related to the support given to students, a factor known to support two extra class, the third factor related aspects of the library, and finalizing the evaluation and approached a factor of 4 facilities. Through research it was concluded that this study presents several points to be improved by the management team, and recommended to continue to evaluate the perceptions of graduates, seeking continuous improvement in service delivery by the university

Fator de decisão na adoção de um sistema de micro-cogeração de energia a gás natural :um estudo em Hotéis três estrelas

The natural gas perform a essential paper, not only in primary sectors of energy, but also in others sectors of economy. The use natural gas will have expansion in Brazil, motivated by governmental decision to increase the participation of this fuel in the Brazilian energy matrix from 4% to 12% up until 2010. in order to reach the objective related to increase the consumption of natural gas in the energy matrix and to propose solutions to attend the electric requirements of heart and refrigeration, using natural gas as primary power plant. This thesis has a main objective to analysis the perception of businessmen of hotel sector about the feasability of investment with micro-cogeneration system by natural gas in their hotel in turistic sector, in Natal/RN. It s show a case for the hotels selected analyzing the actual knowledge of businessmen about alternative of new technology in generation of owner energy. There was make a interview using a standard form researching information about this topic. In this interview has shown 4 (four) canaries for businessmen with different configurations of investment in micro-cogeneration. Two of this canaries uses the project finance like option to make fasible this projects. The resulteis showed who businessmen has insecurity to make decision to put in office alone, or with a local company, and perhaps with a national company to perform for a alternative energy system, justifying, the alone feasability and without information by local businessmen. Apart from that, they are receptive for a option to put in office in micro-cogeneration configured in the settings using project finance

Algoritmo Q-learning como estratégia de exploração e/ou explotação para metaheurísticas GRASP e algoritmo genético

Techniques of optimization known as metaheuristics have achieved success in the resolution of many problems classified as NP-Hard. These methods use non deterministic approaches that reach very good solutions which, however, don t guarantee the determination of the global optimum. Beyond the inherent difficulties related to the complexity that characterizes the optimization problems, the metaheuristics still face the dilemma of xploration/exploitation, which consists of choosing between a greedy search and a wider exploration of the solution space. A way to guide such algorithms during the searching of better solutions is supplying them with more knowledge of the problem through the use of a intelligent agent, able to recognize promising regions and also identify when they should diversify the direction of the search. This way, this work proposes the use of Reinforcement Learning technique - Q-learning Algorithm - as exploration/exploitation strategy for the metaheuristics GRASP (Greedy Randomized Adaptive Search Procedure) and Genetic Algorithm. The GRASP metaheuristic uses Q-learning instead of the traditional greedy-random algorithm in the construction phase. This replacement has the purpose of improving the quality of the initial solutions that are used in the local search phase of the GRASP, and also provides for the metaheuristic an adaptive memory mechanism that allows the reuse of good previous decisions and also avoids the repetition of bad decisions. In the Genetic Algorithm, the Q-learning algorithm was used to generate an initial population of high fitness, and after a determined number of generations, where the rate of diversity of the population is less than a certain limit L, it also was applied to supply one of the parents to be used in the genetic crossover operator. Another significant change in the hybrid genetic algorithm is the proposal of a mutually interactive cooperation process between the genetic operators and the Q-learning algorithm. In this interactive/cooperative process, the Q-learning algorithm receives an additional update in the matrix of Q-values based on the current best solution of the Genetic Algorithm. The computational experiments presented in this thesis compares the results obtained with the implementation of traditional versions of GRASP metaheuristic and Genetic Algorithm, with those obtained using the proposed hybrid methods. Both algorithms had been applied successfully to the symmetrical Traveling Salesman Problem, which was modeled as a Markov decision process

Aplicações da q-Álgebra em física da matéria condensada

We address the generalization of thermodynamic quantity q-deformed by q-algebra that describes a general algebra for bosons and fermions . The motivation for our study stems from an interest to strengthen our initial ideas, and a possible experimental application. On our journey, we met a generalization of the recently proposed formalism of the q-calculus, which is the application of a generalized sequence described by two parameters deformation positive real independent and q1 and q2, known for Fibonacci oscillators . We apply the wellknown problem of Landau diamagnetism immersed in a space D-dimensional, which still generates good discussions by its nature, and dependence with the number of dimensions D, enables us future extend its application to systems extra-dimensional, such as Modern Cosmology, Particle Physics and String Theory. We compare our results with some experimentally obtained performing major equity. We also use the formalism of the oscillators to Einstein and Debye solid, strengthening the interpretation of the q-deformation acting as a factor of disturbance or impurity in a given system, modifying the properties of the same. Our results show that the insertion of two parameters of disorder, allowed a wider range of adjustment , i.e., enabling change only the desired property, e.g., the thermal conductivity of a same element without the waste essence