Análise de superfícies seletivas em frequência com geometria multifractal

Frequency Selective surfaces are increasingly common structures in telecommunication systems due to their geometric and electromagnetic advantages. As a matter of fact, the frequency selective surfaces with fractal geometry type would allow an even bigger reduction of the electrical length which provided greater flexibility in the design of these structures. In this work, we investigated the use of multifractal geometry in frequency selective surfaces. Three structures with different multifractal geometries have been proposed and analyzed. The first structure allowed the design of multiband structures with greater flexibility in controlling the resonant frequencies and bandwidth. The second structure provided a bandwidth increase even with the rising of the fractal level. The third structure showed response with angle stability, dual polarization and provided room for a bandwidth increase with the rising of the structural multifractality. Furthermore, the proposed structures increased the degree of freedom in the multiband designs because they have multiple resonant frequencies ratios between adjacent bands and are easy to deploy. The validation of the proposed structures was initially verified through simulations in Ansoft Designer software and then the structures were constructed and the experimental results obtained

A geometria do compasso (1797) de Mascheroni (1750 – 1800) em atividades com o GeoGebra

The present work aims to show a possible relationship between the use of the History of Mathematics and Information and Communication Technologies (TIC) in teaching Mathematics through activities that use geometric constructions of the “Geometry of the Compass” (1797) by Lorenzo Mascheroni (1750-1800). For this, it was performed a qualitative research characterized by an historical exploration of bibliographical character followed by an empirical intervention based on use of the History of Mathematics combined with TIC through Mathematical Investigation. Thus, studies were performed in papers dealing with the topic, as well as a survey to highlight problems and /or episodes of the history of mathematics that can be solved with the help of TIC, allowing the production of a notebook of activities addressing the resolution of historical problems in a computer environment. In this search, we came across the problems of geometry that are presented by Mascheroni stated previously in the work that we propose solutions and investigations using GeoGebra software. The research resulted in the elaboration of an educational product, a notebook of activities, which was structure to allow during its implementation, students can conduct historical and/or Mathematics research, therefore, we present the procedures for realization of each construction, followed at some moments by original solution of the work. At the same time, we encourage students to investigate/reflect its construction (GeoGebra), in addition to making comparisons with the solution Mascheroni. This notebook was applied to two classes of the course of Didactics of Mathematics I (MAT0367) Course in Mathematics UFRN in 2014. Knowing the existence of some unfavorable arguments regarding the use of history of mathematics, such as loss of time, it was found that this factor can be mitigated with the aid of computational resource, because we can make checks using only the dynamism of and software without repeating the construction. It is noteworthy that the minimized time does not mean loss of reflection or maturation of ideas, when we adopted the process of historical and/or Mathematics Investigation

Aprendizagem significativa: uma proposta de ensino e aprendizagem da geometria euclidiana espacial no ensino médio

This dissertation is a research based on the Meaningful Learning Theory, with students from the second year of High School, in the city named Capinzal do Norte, state of Maranhão. The pedagogic approach of this research focuses on what to do and how to do so students can better grasp knowledge inherent to the Euclidean Special Geometry in a more meaningful and changing way, also that information may be kept longer in their brain, so it can last longer in the present and future. The methodological strategy adopted was the research-action, followed by the constant observance of a researcher on the matter with the purpose to ensure consistent results, which come from the use of a variety of data collector instruments, such as: Concept Maps, manipulatives, educational softwares and application of evaluative tests, besides the observations made throughout the process of investigation and the diagnosis itself. It is all due to the fact that we rely on the premise that knowledge is assimilated in particular and idiosyncratic ways, which means each and every student learns in different ways and in different periods of time. That is why it is so important to develop diversified methodologies to the same subject. This research adds to the other ones related to the theoretical frameworks of the Meaningful Learning Theory, of Concept Maps, of the use of technology on the educational process and of manipulatives, which purpose is to connect their common dots. This pedagogical intervention also focuses on the construction of the educational orientations with applicability directly on class, directed specially by the Mathematics teacher of the basic education, who might use them during your teaching practice. Such guidelines established here as an educational product aim to follow the Theory's assumptions that serves as basis to this research, thus becoming an educational element with a relevant significance. The results, with which we are faced, proved overwhelming to the proposed objectives in terms of learning, which were evident in the construction of Conceptual Maps, as well as in the use of Concrete Materials, in addition to serving as a motivational element to participating students of research. The results obtained are indeed reliable in terms of learning, considered the expected goals, and made us certain that the way we have approached the subject is consistent with a holistic education and that at the same time values the tiniest details, which are fundamental to all the learning-teaching process.

Conhecimento da doença renal crônica entre médicos conforme as diretrizes práticas

INTRODUCTION: Chronic kidney disease (CKD) is a global health problem, with increasing prevalence in its terminal stage and one of the factors that can contribute is the failure to recognize the disease and its risk factors. OBJECTIVE: To evaluate the knowledge of medical residents (MR) and medical preceptors (MP) in hospitals in the Federal University of Rio Grande do Norte in Natal-RN - Brazil, on the DRC, based on the policy of the Kidney Disease Improving Global Outcomes (KDIGO ). METHODS: Cross-sectional study where 64 MR (R1 = 32; R2 = 15; R3 = 17) and 63 MP answered a questionnaire divided into seven sessions that addressed aspects of the DRC since the setting up referral to a nephrologist. RESULTS: Only 20 participants (15.7%) reported using any guidelines for the management of CKD. The scores obtained by session were: Definition and classification (46.1 ± 47.8); Risk factors (70.5 ± 27.9); Laboratory evaluation (58.2 ± 8.8); Clinical action plan (57.6 ± 19.9); Reduction in proteinuria (68.3 ± 15.0); Complications (64.8 ± 19.9); Referral to a nephrologist (73.0 ± 44.6). There was a statistically significant difference between the knowledge of MR and MP in the sessions: Laboratory evaluation (MR 61.5 ± 8.4 vs 54.8 ± 7.9 MP; p <0.001); Reduction in proteinuria (73.1 ± 11.4 vs MR MP 63.5 ± 16.7; p <0.001) and Referral to a nephrologist (MR 81.2 ± 39.3 vs 64.5 ± 48.2 MP; p = 0.035). Among the MR, the R2 obtained the best score (63.9 ± 22.6 vs R1 R2 R3 71.9 ± 17.2 vs 63.5 ± 22.5, p = 0.445). It identified a low percentage of success of the doctors on the definition of CKD (MP = 46%; R1 = 40.6%; R2 = 60%; R3 = 52.9%; p = 0.623) and classification (MP = 34.9%; R1 = 53.1%, R2 = 60%; R3 = 52.9%; p = 0.158). CONCLUSION: The study showed that most doctors do not use any guidelines for clinical management of CKD and that there are gaps in knowledge on the subject, even among physicians who work in the university environment. In this sense, we propose the realization of mini-workshops for participants and students from boarding UFRN, using Case-Based Learning Strategy (CBL), with small group discussion, to strengthen the incorporation of CKD guidelines in undergraduate teaching and in clinical medical practice in general.

Conhecimento da doença renal crônica entre médicos conforme as diretrizes práticas

INTRODUCTION: Chronic kidney disease (CKD) is a global health problem, with increasing prevalence in its terminal stage and one of the factors that can contribute is the failure to recognize the disease and its risk factors. OBJECTIVE: To evaluate the knowledge of medical residents (MR) and medical preceptors (MP) in hospitals in the Federal University of Rio Grande do Norte in Natal-RN - Brazil, on the DRC, based on the policy of the Kidney Disease Improving Global Outcomes (KDIGO ). METHODS: Cross-sectional study where 64 MR (R1 = 32; R2 = 15; R3 = 17) and 63 MP answered a questionnaire divided into seven sessions that addressed aspects of the DRC since the setting up referral to a nephrologist. RESULTS: Only 20 participants (15.7%) reported using any guidelines for the management of CKD. The scores obtained by session were: Definition and classification (46.1 ± 47.8); Risk factors (70.5 ± 27.9); Laboratory evaluation (58.2 ± 8.8); Clinical action plan (57.6 ± 19.9); Reduction in proteinuria (68.3 ± 15.0); Complications (64.8 ± 19.9); Referral to a nephrologist (73.0 ± 44.6). There was a statistically significant difference between the knowledge of MR and MP in the sessions: Laboratory evaluation (MR 61.5 ± 8.4 vs 54.8 ± 7.9 MP; p <0.001); Reduction in proteinuria (73.1 ± 11.4 vs MR MP 63.5 ± 16.7; p <0.001) and Referral to a nephrologist (MR 81.2 ± 39.3 vs 64.5 ± 48.2 MP; p = 0.035). Among the MR, the R2 obtained the best score (63.9 ± 22.6 vs R1 R2 R3 71.9 ± 17.2 vs 63.5 ± 22.5, p = 0.445). It identified a low percentage of success of the doctors on the definition of CKD (MP = 46%; R1 = 40.6%; R2 = 60%; R3 = 52.9%; p = 0.623) and classification (MP = 34.9%; R1 = 53.1%, R2 = 60%; R3 = 52.9%; p = 0.158). CONCLUSION: The study showed that most doctors do not use any guidelines for clinical management of CKD and that there are gaps in knowledge on the subject, even among physicians who work in the university environment. In this sense, we propose the realization of mini-workshops for participants and students from boarding UFRN, using Case-Based Learning Strategy (CBL), with small group discussion, to strengthen the incorporation of CKD guidelines in undergraduate teaching and in clinical medical practice in general.