Acquiring Knowledge the Quilombola Territory of the Jambuaçu River through the Games

This game aims to become a didactic-pedagogical tool to facilitate the interaction and transmission of history, culture and some traditional knowledge of quilombola community living in the Quilombola Territory of the Jambuaçu River, located in the municipality of Mojú, state of Pará, to be applied to the students of the local schools and students of the School of Application of the Federal University of Pará. It also aims to boost the interaction between these different worldviews, through the joint elaboration between quilombola researchers, community members of the Quilombola Territory of the Jambuaçu River and the others researcher

Optimization and synthesis of multilayer frequency selective surfaces via bioinspired hybrid techniques

In this study, two bioinspired computation (BIC) techniques are discussed and applied to the project and synthesis of multilayer frequency selective surfaces (FSS) within the microwave band, specifically for C, X and Ku bands. The proposed BIC techniques consist of combining an artificial, general regression neural network to a genetic algorithm (GA) and a cuckoo search algorithm, respectively. The objective is to find the optimal values of separation between the investigated FSS. Numerical analysis of the electromagnetic properties of the device is made possible with the finite integration method (FIT) and validated through the finite element method (FEM), utilizing both softwares CST Microwave Studio and Ansys HFSS respectively. Thus, the BIC-optimized devices present good phase / angular stability for angles 10°, 20°, 30° and 40°, as well as being polarization independent. The cutoff frequencies to control the operating frequency range of the FSS, referring to transmission coefficient in decibels (dB), were obtained at a threshold of –10dB. Numerical results denote good accordance with measured data

Projeto de um monopolo Hi para aplicações no sistema brasileiro de TV digital

This research deals with the design and analysis of a planar monopole antenna with modified geometry aiming its use for signal reception of digital TV in Brazil working in the of 470 MHz to 806 MHz. Track this contained in the spectrum of UHF-Ultra High Frequency (300 MHz to 3 GHz). To develop this work was taken as reference the antenna called "The Hi Monopole". What originally was presented to operate in UWB (Ultra Wide Band) at 3.1 to 10.6 GHz. For the development of the proposed work, different techniques of adjustment of the antenna can be used for broadband operation, such as: changes in the structure of antenna, resistive loading, switching, using of parasitic elements and matching structures. The design of broadband antennas can be made from three different approaches: time domain, frequency domain and expansion for singularities method. The frequency domain method was employed in this work to the antenna design proposed, some of the techniques mentioned above were analyzed aiming to increase bandwidth, and made a prototype of the antenna to validate the concepts employed. The antenna was designed for the range of 470 MHz to 890 MHz. the prototype built for this same range presented good results, which validates the technique employed. Positive and negative aspects of use of this technique are discussed throughout the work. The commercial computer program CST® MICROWAVE STUDIO, based on the Finite Integration Technique (FIT) was used for simulations in frequency domain.A presente pesquisa trata o projeto e análise de uma antena monopolo planar com geometria modificada visando sua utilização para recepção do sinal de TV digital operante no Brasil na faixa de 470 MHz a 806 MHz. Faixa essa contida no espectro de UHF – Ultra High Frequency (300 MHz a 3 GHz). Para desenvolvimento desse trabalho foi tomado como referência à antena denominada “The Hi Monopole”. Que originalmente foi apresentada para operar em sistemas UWB (Ultra Wide Band) em 3,1 a 10,6 GHz. Para o desenvolvimento do trabalho proposto, diferentes técnicas de adequação da antena podem ser utilizadas para operação em banda larga, tais como: modificação na estrutura da antena, carregamento resistivo, chaveamento, utilização de elementos parasitas e estruturas de casamento. O projeto de antenas banda larga pode ser realizado a partir de três abordagens diferentes: domínio do tempo, domínio da frequência e método de expansão por singularidades. O método no domínio da frequência foi empregado neste trabalho para o projeto da antena proposta, algumas das técnicas supracitadas foram analisadas almejando o aumento da largura de banda, sendo confeccionado um protótipo da antena para validar os conceitos empregados. A antena foi então projetada para a faixa de 470 MHz a 890 MHz. O protótipo construído para essa mesma faixa apresentou bons resultados, o que valida à técnica empregada. Aspectos positivos e negativos do uso desta técnica são discutidos ao longo do trabalho. O programa computacional comercial CST® MICROWAVE STUDIO, baseado na Técnica da Integração Finita (FIT), foi usado para simulações no domínio da frequência

Síntese de superfícies seletivas de frequência para micro-ondas utilizando otimização multiobjetivo bioinspirada

The evolution of computing has made possible substantial advances in research related to engineering and industrial projects. In these areas, the use of computational tools has been intensified for simulation and obtaining certain parameters of the project. However, the growing demand for precision and the gradual increase of the complexity of the structures and systems, results in a simulation process increasingly time-consuming, because the evaluation of a single criterion can consume several hours, as well as several days or even weeks. Therefore, a method that maximizes the time of simulation and optimization, can thus save time and money. In this context, bioinspired computing (BIC), presents accurate and efficient, where many traditional computational methods fail and consists of new mechanism to address such difficulties. Thus, in this work, a study about some of the algorithms used today for BIC design and optimization of general problems in engineering and industry. From now on, one sees develop a metaheuristic optimization code to provide lower-cost computational multiobjective and, consequently, less time for data processing. Initially, an electromagnetic research of frequency selective surfaces with triangular patch elements is done by computer simulations. The numerical analysis is carried out using a full-wave technique based on finite integrals implemented on commercial software performed for simulations in electromagnetism. The synthesis process consists of tuning the resonant frequency of the structures and the bandwidth according to the objectives in the cost function optimization algorithms. The modeling of structures is performed by an artificial neural network and optimization process is performed by meta-heuristics algorithms. The results obtained by these codes are compared to simulated ones by commercial software and measured. A good agreement between simulated and measured results was obtained, as well as a substantial reduction in the processing time of the structures. Finally, conclusions and proposals for further works are presented.A evolução da computação tem possibilitado avanços substanciais em pesquisas relacionadas à engenharia e em projetos industriais. Nestas áreas, o emprego de ferramentas computacionais tem se intensificado para simulação e obtenção de determinados parâmetros do projeto. No entanto, a crescente demanda por precisão e o aumento gradativo da complexidade das estruturas e sistemas, resulta num processo de simulação cada vez mais demorado, pois a avaliação de um único critério pode consumir várias horas, bem como vários dias ou até mesmo semanas. Logo, um método que minimize o tempo de simulação e otimização, pode, assim, economizar tempo e dinheiro. Nesse contexto, a computação bioinspirada (bioinspired computing - BIC), se apresenta precisa e eficiente, onde muitos métodos computacionais tradicionais falham e, consiste em novo mecanismo para suprir tais dificuldades. Assim, neste trabalho, é realizado um estudo acerca de alguns dos algoritmos BIC mais utilizados na atualidade para projeto e otimização de problemas gerais na engenharia e na indústria. Doravante, se vislumbra desenvolver um código de otimização meta-heurístico multiobjectivo que apresente menor custo computacional e, consequentemente, menor tempo para processamento dos dados. Inicialmente, é realizada uma investigação eletromagnética das superfícies seletivas de frequência triangulares estudadas, através de simulações computacionais. A análise numérica de onda completa é feita pela técnica das integrais finitas com o auxílio de um software comercial muito utilizado para simulações em eletromagnetismo. O processo de síntese consiste em sintonizar a frequência de ressonância das estruturas e a largura de banda de acordo com os objetivos inseridos na função custo dos algoritmos de otimização. A modelagem das estruturas é realizada por uma rede neural artificial e o processo de otimização é realizado por algoritmos meta-heurísticos. Os resultados obtidos por esses códigos são comparados aos simulados pelo software comercial e aos medidos. Observou-se boa concordância entre os resultados simulados e medidos, bem como uma substancial redução no menor tempo de processamento das estruturas. Por fim, são apresentadas as conclusões e as propostas para trabalhos futuros

Hybrid computational and real data-based positioning of small cells in 5G networks

One of the key technologies in smart cities is the use of next generation networks such as 5G networks. Mainly because this new mobile technology offers massive connections in densely populated areas in smart cities, thus playing a crucial role for numerous subscribers anytime and anywhere. Indeed, all the most important infrastructure to promote a connected world is being related to next generation networks. Specifically, the small cells transmitters is one of the 5G technologies more relevant to provide more connections and to attend the high demand in smart cities. In this article, a smart small cell positioning is proposed in the context of a smart city. The work proposal aims to do this through the development of a hybrid clustering algorithm with meta-heuristic optimizations to serve users, with real data, of a region satisfying coverage criteria. Furthermore, the problem to be solved will be the best location of the small cells, with the minimization of attenuation between the base stations and its users. The possibilities of using multi-objective optimization algorithms based on bioinspired computing, such as Flower Pollination and Cuckoo Search, will be verified. It will also be analyzed by simulation which power values would allow the continuity of the service with emphasis on three 5G spectrums used around the world: 700 MHz, 2.3 GHz and 3.5 GHz

Video loss prediction model in wireless networks.

This work discusses video communications over wireless networks (IEEE 802.11ac standard). The videos are in three different resolutions: 720p, 1080p, and 2160p. It is essential to study the performance of these media in access technologies to enhance the current coding and communications techniques. This study sets out a video quality prediction model that includes the different resolutions that are based on wireless network terms and conditions, an approach that has not previously been adopted in the literature. The model involves obtaining Service and Experience Quality Metrics, such as PSNR (Peak Signal-to-Noise Ratio) and packet loss. This article outlines a methodology and mathematical model for video quality loss in the wireless network from simulated data and its accuracy is ensured through the use of performance metrics (RMSE and Standard Deviation). The methodology is based on two mathematical functions, (logarithmic and exponential), and their parameters are defined by linear regression. The model obtained RMSE values and standard deviation of 2.32 dB and 2.2 dB for the predicted values, respectively. The results should lead to a CODEC (Coder-Decoder) improvement and contribute to a better wireless networks design

SNR Prediction with ANN for UAV Applications in IoT Networks Based on Measurements

The 5G deployment brings forth the usage of Unmanned Aerial Vehicles (UAV) to assist wireless networks by providing improved signal coverage, acting as relays or base-stations. Another technology that could help achieve 5G massive machine-type communications (mMtc) goals is the Long Range Wide-Area Network (LoRaWAN) communication protocol. This paper studied these complementary technologies, LoRa and UAV, through measurement campaigns in suburban, densely forested environments. Downlink and uplink communication at different heights and spreading factors (SF) demonstrate distinct behavior through our analysis. Moreover, a neural network was trained to predict the measured signal-to-noise ratio (SNR) behavior and results compared with SNR regression models. For the downlink scenario, the neural network results show a root mean square error (RMSE) variation between 1.2322–1.6623 dB, with an error standard deviation (SD) less than 1.6730 dB. For the uplink, the RMSE variation was between 0.8714–1.3891 dB, with an error SD less than 1.1706 dB