Gestão estratégica da segurança do trabalho na área industrial de uma usina de etanol, açúcar e energia elétrica

Conseguir lucratividade em uma usina produtora de etanol, açúcar e energia elétrica, sem acidentes do trabalho, passou a ser grande desafio. Portanto, a Gestão de Segurança transformou-se em estratégica, buscando levar o valor empresarial “segurança” como instrumento fundamental na execução da produção. Levantamos a história da implantação do Sistema de Gestão da Segurança da usina e também checamos através de indicadores universais de segurança, se os números alcançados, apresentam evolução satisfatória, procurando identificar as ações aplicadas e os resultados. No processo de evolução desse sistema, a usina tornou-se a primeira do mundo na obtenção de uma Certificação Internacional de Segurança (OHSAS 18001) do setor sucroenergético, além de alcançar quarto lugar em processamento de cana no Brasil. Aplicando o Instrumento ICOS – Inventário de Clima Organizacional de Segurança em 2005 e novamente em 2011, avaliamos se com crescimento da produção, aliado ao aumento do número de trabalhadores, o valor segurança manteve-se presente. Também apuramos possíveis fatores como tempo de empresa, escolaridade, proporção de acidentes e entrevistas com os responsáveis que contribuíram para a existência de setores há 16 anos sem perder um dia de trabalho por acidente. Finalmente, concluímos que lidar com gestão da segurança, capacita a empresa para enfrentar dificuldades do mercado, pois sucesso hoje, pode não valer para o dia seguinte caso ocorra acidente. Prevenir, educar, buscar conhecimento, celebrar, cobrar resultados e ousadia, definem o estilo de administração da usina estudada.

Gestão de riscos na cadeia de suprimentos e valoração do custo da escassez de energia elétrica: Modelos e uma proposta de implementação para o Brasil

Este trabalho apresenta as principais aplicações de técnicas de gestão de riscos ao estudo de interrupções em cadeias de fornecimento, tendo como motivação o caso do fornecimento de energia elétrica, assunto de extrema relevância para o Brasil. Neste sentido, o cálculo do “custo do déficit” ou perda de produção dada uma falha no fornecimento de energia elétrica (parâmetro utilizado em todo o planejamento do setor elétrico brasileiro), foi escolhido como fator relevante a ser analisado. As principais metodologias existentes para a apuração desse parâmetro são apresentadas fazendo uma comparação com aquela atualmente em uso no Brasil. Adicionalmente, apresentamos uma proposta de implementação para as metodologias alternativas, utilizadas no exterior, e baseadas no conceito de VOLL (“Value of Lost Load”) - medida do valor da escassez de energia para empresas ou consumidores individuais e fundamental para o desenho de programas de gerenciamento de demanda.

A história do "turismo social" no Serviço Social do Comércio - SP

Este trabalho é fruto de uma investigação realizada no doutorado em História, Política e Bens Culturais do Centro de Pesquisa e Documentação de História Contemporânea do Brasil da Fundação Getulio Vargas - orientada pela profa. Dra. Bianca Freire-Medeiros - acerca da constituição e implementação do turismo social no Serviço Social do Comércio do estado de São Paulo (Sesc-SP), examinando as circunstâncias em que o lazer e as experiências turísticas tornam-se relevantes nas políticas e ações da entidade. Procurou-se entender as transformações e readequações que nortearam as iniciativas da instituição e como as modificações no conceito de turismo social no Brasil e no mundo vêm dialogando com suas diretrizes, posturas e intenções. A metodologia privilegiada na pesquisa foi a história oral temática, no intuito de fazer o registro da história do envolvimento de profissionais com o turismo social do Sesc-SP. Foram realizadas vinte e duas entrevistas com (ex)profissionais e feitas algumas visitas à Biblioteca do departamento nacional do Sesc (Sesc-DN) e ao setor de memória e documentação (Sesc-Memórias) do departamento regional paulista do Sesc, lugares que congregam documentos importantes relacionados à história do turismo na instituição. Espacialmente a pesquisa situa-se no Sesc-SP, repartição atuante e “atenta” às ideias e mudanças envolvendo o turismo social, e representativa na história do fenômeno, no Brasil e no mundo. A circunscrição temporal da pesquisa abarca desde 1979 - ano em que o Sesc de São Paulo passa a desenvolver excursões, passeios e viagens com maior frequência e tenta se aprofundar conceitualmente do turismo social ao se aproximar de órgãos internacionais de relevância política e científica na área - até as ações realizadas em 2013, ano no qual termino a pesquisa de campo e as entrevistas. Durante a trajetória da pesquisa, dialoguei com o período que antecede este recorte, acerca dos empreendimentos do Sesc relacionados as práticas de lazer e turismo, gerando o capítulo 2. Antes, no capítulo 1, tentei reconhecer o lugar do turismo social na história das atividades turísticas no mundo, entendendo-o enquanto oportunidade de efetivação do direito ao lazer. Para alcance dos intentos da tese, como fontes foram utilizados documentos produzidos em âmbito institucional, articulados com a fala dos indivíduos entrevistados, trabalho conjugado especialmente no capítulo 3, em que trago reflexões a respeito do turismo social desenvolvido pelo Sesc-SP. Dentre as análises alvitradas, descrevo a dificuldade encontrada pela entidade ao expandir suas atividades turísticas, vindo a sofrer represálias do setor privado. Deve-se destacar que foi possível perceber a metamorfose conceitual/prática por qual passara o turismo social no Sesc-SP, agregando diferentes conteúdos ao fenômeno e modificando seus processos de trabalho e práticas profissionais. Ressalto ainda o papel ideológico da administração regional do Sesc-SP dentro do Serviço Social do Comércio no Brasil, notadamente na área do turismo. Por fim, envolvo no debate da tese as políticas sociais de turismo, compreendido enquanto possibilidade de lazer.

Elementos de confiança e cultura organizacional que dificultam a gestão pro processos na área de tecnologia da informação e telecomunicações de uma empresa de energia

Este estudo é dedicado à compreensão dos fatores culturais e de confiança que dificultam o alinhamento por processos na área de Tecnologia da Informação e Telecomunicações de uma empresa de economia mista. Visa compreender e traduzir o modo como a cultura dessa organização impacta nos resultados alcançados pelo modelo de gestão por processos vigente. Fazendo uso de referencial teórico das áreas de estudo de cultura organizacional, cultura nacional e confiança nas organizações, este estudo buscou alinhar estes conhecimentos por meio de um viés ainda pouco explorado no ambiente acadêmico. Aqui fizemos uso do conceito de cultura como um meio e não como um fim em si, associando classificação da cultura em dimensões, os traços da cultura brasileira e os estudos de “confiança” numa mescla ordenada de conceitos capaz de nos responder à questão de pesquisa. Esta pesquisa representa o resultado de um esforço de imersão nas rotinas da organização e descrição dos seus elementos culturais por meio de observação e entrevistas no ambiente estudado. Por fim, este trabalho se destina a contribuir ao aprimoramento dos processos para atingir melhores resultados na TIC.

O programa nuclear brasileiro: uma história oral

Centro de Pesquisa e Documentação de História Contemporânea do Brasil

Otimização de microprodução em redes inteligentes de energia

As energias renováveis têm-se tornado uma alternativa viável e complementar aos combustíveis fósseis, pelo facto de serem energias virtualmente inesgotáveis, limpas e economicamente vantajosas. Um dos principais problemas associados às fontes de energia renováveis é a sua intermitência. Este problema impossibilita o controlo da produção de energia e reflete-se na qualidade da energia elétrica. Em sistemas de microprodução de energia, este problema pode ser atenuado com a inclusão de sistemas de armazenamento intermédio que possibilitam o armazenamento do excedente extraído das fontes renováveis, podendo ser utilizado como recurso auxiliar na alimentação de cargas ou como meio de estabilização e otimização do desempenho da Rede Elétrica de Energia (REE), evitando variações bruscas na energia transferida para a mesma. Os sistemas de microprodução com armazenamento intermédio podem ser considerados fundamentais na implementação do conceito de Rede Inteligente de Energia (RIE), visto serem sistemas de energia descentralizados que permitem uma melhor gestão da energia elétrica e uma consequente redução de custos. No presente trabalho desenvolveu-se um sistema de microprodução de energia renovável compatível com as fontes renováveis fotovoltaica e eólica, possuindo um banco de baterias como sistema de armazenamento intermédio. A construção deste sistema teve como principal objetivo seguir as referências de potência impostas pela RIE, independentemente das condições meteorológicas, com recurso à energia armazenada nas baterias, evitando a introdução de perturbações na REE ao nível da tensão e da frequência. Estudou-se o comportamento do sistema na ocorrência de variações bruscas da fonte renovável, perturbações na tensão da REE e introdução de cargas lineares e não lineares. Foi desenvolvido um protótipo experimental com painéis fotovoltaicos, no qual foram registados os valores de alguns parâmetros da qualidade da energia elétrica. Obteve-se uma resposta de aproximadamente 25 μs por parte das baterias para cada Watt de potência requisitado pela RIE.

A dimensão simbólica e midiática da política e a história da dona de casa que virou guerreira : a construção da imagem pública de Wilma de Faria em 2002 e 2006

This paper examines two aspects. First, the symbolic dimension of politics and some of the elements that make up this universe, as the scenario, the representation, the myth, the spectacle, the media and the political and electoral marketing. We assume that the policy brings together a set of traits related to both reason and the human subjectivity, and can not be summed up in just a few calculations based on rationality. In the case of elections, in a process (ritual, according Irlys Barrier) of choice, there is a meeting of two systems of representations: to that transmitted by a political actor, in a scene from a particular context, based on a life trajectory unique, and the other from the public, crossed by social relations, situations own wishes, desires, expectations and unique perspectives. Between them there are the means of mass media (especially television), and with them the advent of language media and advertising applied to politics, changing the layout of public visibility and inaugurating what Rejane Accioly Carvalho will call the "aesthetics of mostrabilidade". This does not necessarily mean a preponderance of media on politics as a whole but only its adaptation to that with regard to contact with the public, the ad extra portion of the policy, according to Wilson Gomes. In a second aspect, try to apply these elements to a specific study to verify them in building an effective public image, in this case, the current governor of Rio Grande do Norte, Wilma de Faria. The concept of public image is from the book of Wilson Gomes The transformation was visible in the mass media, and relates to a conceptual image to fix "personality traits" through political history, personal conduct, action of image makers and the public reception. For this we will review some videos aired on Free Time for political propaganda in the years 2002 and 2006.

Uma análise histórico-epistemológica do conceito de grupo

This work aims to analyze the historical and epistemological development of the Group concept related to the theory on advanced mathematical thinking proposed by Dreyfus (1991). Thus it presents pedagogical resources that enable learning and teaching of algebraic structures as well as propose greater meaning of this concept in mathematical graduation programs. This study also proposes an answer to the following question: in what way a teaching approach that is centered in the Theory of Numbers and Theory of Equations is a model for the teaching of the concept of Group? To answer this question a historical reconstruction of the development of this concept is done on relating Lagrange to Cayley. This is done considering Foucault s (2007) knowledge archeology proposal theoretically reinforced by Dreyfus (1991). An exploratory research was performed in Mathematic graduation courses in Universidade Federal do Pará (UFPA) and Universidade Federal do Rio Grande do Norte (UFRN). The research aimed to evaluate the formation of concept images of the students in two algebra courses based on a traditional teaching model. Another experience was realized in algebra at UFPA and it involved historical components (MENDES, 2001a; 2001b; 2006b), the development of multiple representations (DREYFUS, 1991) as well as the formation of concept images (VINNER, 1991). The efficiency of this approach related to the extent of learning was evaluated, aiming to acknowledge the conceptual image established in student s minds. At the end, a classification based on Dreyfus (1991) was done relating the historical periods of the historical and epistemological development of group concepts in the process of representation, generalization, synthesis, and abstraction, proposed here for the teaching of algebra in Mathematics graduation course

O livro didático de história: um caleidoscópio de escolhas e usos no cotidiano escolar (Ceará, 2007 2009)

In the first decade of the XXI century, it is possible to assert that school textbook is part of the material culture of most public Brazilian schools by means of National School Textbook Program (PNLD). This research aimed at identifying and analyzing textbooks choice in Ceara, relating it to the uses of such tool within school daily life. The setting for the study was four public schools, two of them placed in Fortaleza, and the other in Quixada. It evaluated the uses of textbooks in the 6th grade. As part of methodology, public managers were interviewed, teachers answered surveys, and a direct observation during History classes in 2008 school year was carried out. The observation was over after round chats with students in the class, in which each one designed draws and sentences concerning to the textbook. Furthermore, the study was based on MEC official documents that regulate the textbook choice process with National textbook Program announcement (PNDL/2008) and PNDL/2008 Textbook Guide, in addition to History textbooks schools used. Roger Chartier‟s concept of appropriation was an analysis category, as well as Michael de Certeau s strategy and tatics‟, and Dominique Julia‟s concept of school culture . The study recognizes textbook in the perspective of Alain Choppin and Egil Borre Johnsen, since it is a complex cultural object. For this reason, the study designs an analogy with a kaleidoscope that sends different images depending on who uses it, within a set of colorful lines, since textbook comprehends nowadays different sources and languages, as it offers countless possibilities of use in teaching History. The study concludes that only the main text of each chapter is really worked in daily class practice. Therefore, although theoretical and graphic changes in textbook production, the textbook is underused, which is central to a later rethought of teachers instruction, since, depending on the conception of teaching and learning, textbook potentialities will be used to improve the development of knowledge in History.

Anayde Beiriz e a escrita de si: (Educação, história e relações de gênero)

Le thème de cette dissertation est l Histoire de l éducation de la femme. Une analyse des pratiques culturelles de la professeur Anayde da Costa Beiriz (1905-1930), dans le contexte paraibanais du début du XXe siècle, est proposée. Le référentiel théoricométhodologique de l Histoire Culturelle est utilisé, pour aller contre l histoire passée sous silence dans le canon traditionnel. Basée sur le concept de représentation (Chartier, 1990), rompant avec les anciennes idées de sens intrinsèque, absolu, unique, liée aux pratiques complexes, multiples et différenciées, qui construisent le monde comme représentation. Basée aussi sur le concept de configuration (Elias, 1980), en comprenant que apparemment individu et société sont deux objets qui existent indépendamment, mais en vérité, se rapportent à deux niveaux inséparables du monde social, sont unis par des liens d interdépendance. Un dialogue est recherché entre le passé et le présent et les différentes dimensions: historique, sociale, politique et culturelle vécues par la professeur Anayde Beiriz. Pour obtenir des informations sur ses pratiques culturelles, une recherche des marques de cette histoire dans de multiples sources est effectuée: dans la bibliographie disponible parmi les domaines de la littérature, de l histoire, dês sciences sociales et de l éducation; dans des archives de l Institut Historique et Géographique de la Paraiba et de Natal; dans les Bibliothèques de l Université Fédérale de la Paraiba et du Rio Grande do Norte et chez des bouquinistes. L inventaire comprend: des périodiques, la législation en vigueur, des écrits de contemporains, dês témoignages oraux de parents, des lettres et des photos. On comprend de cette façon, que l idée d éplucher au travers de cette étude, des aspects qui n ont pas encore été vus et rappelés, peut non seulement répondre à nos doutes, mais, peut à partir de la réflexion qui se fait, se traduire par une nouvelle compréhension de cette histoire. En conclusion, des significations multiples sont contenues dans le processus d insertion de la femme dans l éducation à partir des Écoles Normales, qui englobent les relations de genre, l histoire du pouvoir, de la morale, de surpassement, des luttes et insatisfactions. On perçoit l héritage de résistances et de conquêtes. Cela a été sous l inspiration des airs de la modernité avec la Belle Époque, en répercutant dans le monde et aussi dans la Parahyba du Nord, que s est concrétisée la formation sociale de la professeur Anayde Beiriz et des femmes de son temps. L analyse de l écriture de soi confirme le discours normatif du contrôle moral social, le joug et les préjugés soufferts par Anayde Beiriz et l éducation différencié de genre qui ont déterminé ses habitudes et coutumes. C est-àdire, pour la femme, la permanence dans l espace privé, la retenue, l anoblissement des tâches ménagères et de la maternité comme sa plus haute aspiration, le support moral de la famille, la préservation de la tradition et la perpétuation des règles religieuses

Quadrinhos nas aulas de ciências: narrando uma história de formação continuada

Located at the intersection of Science Education, Teacher Training and use of didactic Comics (HQ), the text aims to discuss the problem which thus sets: - What is the contribution of the incorporation of comics in the continuing education of teachers Natural Sciences of the early years of elementary school? - May be the comics for enabling science teaching? - How to contribute to a reflexive training of teachers of the early years? - In order to answer these questions, there was a collaborative action research in a school located in the city of Natal / RN, with three teachers who teach natural science in the early years of elementary school. The study involved the conduct of 13 meetings of in-service, under the focus on reflective practice, with the purpose of discussing topics underlying the teaching of science and the use of comics as a methodological strategy. All meetings were recorded on audio and transcripts. The teachers finally recorded the meetings by writing a portfolio. The teachers made use of 10 sessions with reading comics in science classes, which were video recorded and later watched by the educators in autoscopy sessions followed by individual interviews. From the collected data, several aspects that have emerged can be grouped into three categories: The difficult concept of science, teachers' work and the obstacles and possibilities of comics as a teaching strategy. In this sense, are woven assessments taking as its founding, look for the reflective and dialogic practices exercised in the classroom. In the analysis of the data, we can see the conceptual difficulties, methodological and pistemological questions of teachers for teaching science, but also the limitations of comic books for teaching. Learning more relevant appointed by the teachers is related to the importance of collective work to mitigate the training needs of teaching. Finally, signals that the HQ has a great potential for use in science classes, provided that the teacher conduct a careful planning for this, but that the meetings of continuing education promote moments of reflection on teaching practices that are capable of giving rise to new attitudes before the difficulties they depict

Corporeidade e humanescência: cenários ludopoiéticos na vida de professores contadores de história

During the latest years, the art of storytelling has received special attention from those who make education, art and culture. The storyteller is a singular person who manages to seduce itself and its listeners, by involving them in an atmosphere of pleasure and complicity, dodging situations, space and time, providing delight, stimulating creativity, daydreaming and imagination. This is a study developed with storyteller teachers that takes as its starting point the need to change the landscape of education, which seeks to emphasize the affirmation of embodiment of the teacher, so that it participates in a creative self-dynamic and the context in which they live. In addition , the following purposes accompanied the study : education - liberating practice and human development ; corporality - radiant , first and main focus of educational criteria; playfulness - a human dimension ; autopoiese - as an organization of human beings that produces and continuously transforms itself; flow experience concerns the feeling of full involvement in the activity , the psychic energy toward something that is being produced or performed , something that brings us pleasure , happiness and profound sense of well being. As general objective of the study we analysed the humanescent self-formation and its ludopoiética nature in storyteller teachers from humanescent workshops developed in a state school in Natal / RN. In view of the overall objective , we developed the following specific objectives : to identify the ludopoiéticas properties of self-worth , self-connectivity , self-territoriality , autotelia and self realization present in the life of storyteller teachers and the changes in the school environment, from the development of humanescent workshops; reveal the nature of humanescent self-training in storyteller teachers lives. The investigated group had the participation of eight teachers, and had the Escola Estadual Potiguassu as environment for the research. This is a descriptive study, understood as an action-research , developed with basis in the fundamentals and ethnomethodological principles , which used eight humanescents workshops , developed in the context of humanescent experiential pedagogy in conjunction with participant observation .The analyzes were focused on the chosen categories for the study : self-worth , self-connectivity , self-territoriality , autotelia and self-, indexicality and reflexivity . In terms of conclusions, we noted that the properties of ludopoiese were unveiled in the lives of the teachers by providing changes in their ways of being and living together. The teachers have become more creative and intensely began to experience their own life, social life, as well as its meaning. The struggle for a more cheerful and happy school was another important development highlighted in the reports of the teachers, also observing that there was a significant improvement in the reduction of violence in the school environment. Thus, we emphasize that the teachers began to recognize themselves like being ludic, playing with the beauty of storytelling and life

Uso de técnicas de otimização baseadas em derivadas como suporte do planejamento operacional de redes de distribuição de energia elétrica

The usual programs for load flow calculation were in general developped aiming the simulation of electric energy transmission, subtransmission and distribution systems. However, the mathematical methods and algorithms used by the formulations were based, in majority, just on the characteristics of the transmittion systems, which were the main concern focus of engineers and researchers. Though, the physical characteristics of these systems are quite different from the distribution ones. In the transmission systems, the voltage levels are high and the lines are generally very long. These aspects contribute the capacitive and inductive effects that appear in the system to have a considerable influence in the values of the interest quantities, reason why they should be taken into consideration. Still in the transmission systems, the loads have a macro nature, as for example, cities, neiborhoods, or big industries. These loads are, generally, practically balanced, what reduces the necessity of utilization of three-phase methodology for the load flow calculation. Distribution systems, on the other hand, present different characteristics: the voltage levels are small in comparison to the transmission ones. This almost annul the capacitive effects of the lines. The loads are, in this case, transformers, in whose secondaries are connected small consumers, in a sort of times, mono-phase ones, so that the probability of finding an unbalanced circuit is high. This way, the utilization of three-phase methodologies assumes an important dimension. Besides, equipments like voltage regulators, that use simultaneously the concepts of phase and line voltage in their functioning, need a three-phase methodology, in order to allow the simulation of their real behavior. For the exposed reasons, initially was developped, in the scope of this work, a method for three-phase load flow calculation in order to simulate the steady-state behaviour of distribution systems. Aiming to achieve this goal, the Power Summation Algorithm was used, as a base for developing the three phase method. This algorithm was already widely tested and approved by researchers and engineers in the simulation of radial electric energy distribution systems, mainly for single-phase representation. By our formulation, lines are modeled in three-phase circuits, considering the magnetic coupling between the phases; but the earth effect is considered through the Carson reduction. It s important to point out that, in spite of the loads being normally connected to the transformer s secondaries, was considered the hypothesis of existence of star or delta loads connected to the primary circuit. To perform the simulation of voltage regulators, a new model was utilized, allowing the simulation of various types of configurations, according to their real functioning. Finally, was considered the possibility of representation of switches with current measuring in various points of the feeder. The loads are adjusted during the iteractive process, in order to match the current in each switch, converging to the measured value specified by the input data. In a second stage of the work, sensibility parameters were derived taking as base the described load flow, with the objective of suporting further optimization processes. This parameters are found by calculating of the partial derivatives of a variable in respect to another, in general, voltages, losses and reactive powers. After describing the calculation of the sensibility parameters, the Gradient Method was presented, using these parameters to optimize an objective function, that will be defined for each type of study. The first one refers to the reduction of technical losses in a medium voltage feeder, through the installation of capacitor banks; the second one refers to the problem of correction of voltage profile, through the instalation of capacitor banks or voltage regulators. In case of the losses reduction will be considered, as objective function, the sum of the losses in all the parts of the system. To the correction of the voltage profile, the objective function will be the sum of the square voltage deviations in each node, in respect to the rated voltage. In the end of the work, results of application of the described methods in some feeders are presented, aiming to give insight about their performance and acuity

Investigação histórica na formação de professores de matemática: um estudo centrado no conceito de função

In this study we analyzed the development of a teaching experience, involving students with a bachelor s degree in mathematics from UFRN, based on the history of mathematics and mathematical investigations with the aim of contributing to the improvement of the teaching-learning of mathematics. The historical investigation tasks were planned and applied in the classroom, focusing on functional thought. The results obtained during the experience were described and evaluated based on authors who support the assumption of investigation and history as an alternative to the learning of mathematics. We emphasize that the material of analysis consisted of a work diary, audio recordings, questionnaires with testimony of the students involved, and, in addition, the assessment of the teacher of that subject. With regard to the mathematical content, the study was restricted to the concept of function, forms of representation and notation. It was evident that students showed great improvement with regard to the necessary formalization of the mathematical contents which were focused on, and to the active involvement of the students at different stages of the study. We can affirm that the completed study certainly represents significant contributions to an approach in the teaching-learning of functional thought

O uso pedagógico de uma seqüência didática para a aquisição de algumas idéias relacionadas ao conceito de números complexos

The aim of the present work is to contribute to the teaching-learning process in Mathematics through an alternative which tries to motivate the student so that he/she will learn the basic concepts of Complex Numbers and realize that they are not pointless. Therefore, this work s general objective is to construct a didactic sequence which contains structured activities that intends to build up, in each student s thought, the concept of Complex Numbers. The didactic sequence is initially based on a review of the main historical aspects which begot the construction of those numbers. Based on these aspects, and the theories of Richard Skemp, was elaborated a sequence of structured activities linked with Maths history, having the solution of quadratic equations as a main starting point. This should make learning more accessible, because this concept permeates the students previous work and, thus, they should be more familiar with it. The methodological intervention began with the application of that sequence of activities with grade students in public schools who did not yet know the concept of Complex Numbers. It was performed in three phases: a draft study, a draft study II and the final study. Each phase was applied in a different institution, where the classes were randomly divided into groups and each group would discuss and write down the concepts they had developed about Complex Numbers. We also use of another instrument of analysis which consisted of a recorded interview of a semi-structured type, trying to find out the ways the students thought in order to construct their own concepts, i.e. the solutions of the previous activity. Their ideas about Complex Numbers were categorized according to their similarities and then analyzed. The results of the analysis show that the concepts constructed by the students were pertinent and that they complemented each other this supports the conclusion that the use of structured activities is an efficient alternative for the teaching of mathematics