Oficina educomunicativa de produção de vídeos: construção de significados sobre problemas socioambientais

This research aims to analyze the meaning making by Elementary Education students from public schools of Uberlândia (Minas Gerais, Brazil) about the social and environmental problems of their surroundings as of audiovisual reading and expression skills. The theoretical framework is based on constructivism, through the study of contributions about: cognitive development; meaningful learning; cognitive processes and types of knowledge; principles of learning with technology; educommunication focused on critical media literacy; and critical environmental education. The study object is a video production workshop organized in nine meetings, from September to November 2015, attended by 15 students. The following data collection instruments were used: the materials produced by the participants, specifically guided critical media literacy, agenda, script and final video; researcher observations from his role as a mediator; and focal interviews. The analysis was divided into two axes: procedural knowledge – technical skills of critical media literacy and production; and conceptual and metacognitive knowledge – representation of social and environmental problems and metacognitive skills of critical media literacy. Data were coded in the form of a skill evaluation rubric and also in the form of graphs. Thus, despite the time constraints, it is inferred that the workshop helped students to deepen their understanding about the discussed content, which is reinforced by observing in the graphs how the constant progressive differentiation of more inclusive concepts occurred along the meetings. It is further considered that the workshop contributed to the students reflect on their way of learning through critical use of techniques of media literacy and production, which can be seen from the satisfactory learners performance in most elements evaluated by the rubrics, as well as from the success in identifying interlocutors, values and actions in the read and built texts, something revealed by the graphs.

Utilização da transformada de wavelet para detecção de variações anormais de tensão em sistemas elétricos com geração distribuída

The increasing demand in electricity and decrease forecast, increasingly, of fossil fuel reserves, as well as increasing environmental concern in the use of these have generated a concern about the quality of electricity generation, making it well welcome new investments in generation through alternative, clean and renewable sources. Distributed generation is one of the main solutions for the independent and selfsufficient generating systems, such as the sugarcane industry. This sector has grown considerably, contributing expressively in the production of electricity to the distribution networks. Faced with this situation, one of the main objectives of this study is to propose the implementation of an algorithm to detect islanding disturbances in the electrical system, characterized by situations of under- or overvoltage. The algorithm should also commonly quantize the time that the system was operating in these conditions, to check the possible consequences that will be caused in the electric power system. In order to achieve this it used the technique of wavelet multiresolution analysis (AMR) for detecting the generated disorders. The data obtained can be processed so as to be used for a possible predictive maintenance in the protection equipment of electrical network, since they are prone to damage on prolonged operation under abnormal conditions of frequency and voltage.

Uma estratégia para otimizar a geração de arranjos em subestações virtuais de energia elétrica

The Virtual Reality techniques applied in Electricity Environments provide a new supervisory control paradigm. The fact of existing a virtual environment (VE), geometrically similar to a real substation, reduces the difference of mental models built by field operators compared with those built by system center operation improving the communication. Beside this, those systems can be used as visualization interfaces for electricity system simulators, training systems for professors and undergraduate students, field operators and maintenance professionals. However, the development process of these systems is quite complex, combining several activities such as implementation, 3D modeling, virtual sceneries construction, usability assessment and management project techniques. In this context, this work present a GUI strategy to build field arrangements based on scene graphs, to reduce time in Virtual Electricity Substations Arrangement development. Through this, mistakes during the VE building can be avoided making this process more reliable. As an concept proof, all toolkits developed in this work were applied in the virtualization of the substations from a Brazilian power concessionary named CEMIG.

Uma metodologia para geração otimizada de ambientes virtuais baseados em usinas hidrelétricas

Based on the possibility of real-time interaction with three-dimensional environments through an advanced interface, Virtual Reality consist in the main technology of this work, used in the design of virtual environments based on real Hydroelectric Plants. Previous to the process of deploying a Virtual Reality System for operation, three-dimensional modeling and interactive scenes settings are very importante steps. However, due to its magnitude and complexity, power plants virtual environments generation, currently, presents high computing cost. This work aims to present a methodology to optimize the production process of virtual environments associated with real hydroelectric power plants. In partnership with electric utility CEMIG, several HPPs were used in the scope of this work. During the modeling of each one of them, the techiniques within the methodologie were addressed. After the evaluation of the computional techniques presented here, it was possible to confirm a reduction in the time required to deliver each hydroelectrical complex. Thus, this work presents the current scenario about development of virtual hydroelectric power plants and discusses the proposed methodology that seeks to optimize this process in the electricity generation sector.