UAV-Multispectral Sensed Data Band Co-Registration Framework

Precision farming has greatly benefited from new technologies over the years. The use of multispectral and hyperspectral sensors coupled to Unmanned Aerial Vehicles (UAV) has enabled farms to monitor crops, improve the use of resources and reduce costs. Despite being widely used, multispectral images present a natural misalignment among the various spectra due to the use of different sensors. The variation of the analyzed spectrum also leads to a loss of characteristics among the bands which hinders the feature detection process among the bands, which makes the alignment process complex. In this work, we propose a new framework for the band co-registration process based on two premises: i) the natural misalignment is an attribute of the camera, so it does not change during the acquisition process; ii) the speed of displacement of the UAV when compared to the speed between the acquisition of the first to the last band, is not sufficient to create significant distortions. We compared our results with the ground-truth generated by a specialist and with other methods present in the literature. The proposed framework had an average back-projection (BP) error of 0.425 pixels, this result being 335% better than the evaluated frameworks.CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorDissertação (Mestrado)A agricultura de precisão se beneficiou muito das novas tecnologias ao longo dos anos. O uso de sensores multiespectrais e hiperespectrais acoplados aos Veículos Aéreos Não Tripulados (VANT) permitiu que as fazendas monitorassem as lavouras, melhorassem o uso de recursos e reduzissem os custos. Apesar de amplamente utilizadas, as imagens multiespectrais apresentam um desalinhamento natural entre os vários espectros devido ao uso de diferentes sensores. A variação do espectro analisado também leva à perda de características entre as bandas, o que dificulta o processo de detecção de atributos entre as bandas, o que torna complexo o processo de alinhamento. Neste trabalho, propomos um novo framework para o processo de alinhamento entre as bandas com base em duas premissas: i) o desalinhamento natural é um atributo da câmera, e por esse motivo ele não é alterado durante o processo de aquisição; ii) a velocidade de deslocamento do VANT, quando comparada à velocidade entre a aquisição da primeira e a última banda, não é suficiente para criar distorções significativas. Os resultados obtidos foram comparados com o padrão ouro gerado por um especialista e com outros métodos presentes na literatura. O framework proposto teve um back-projection error (BP) de 0, 425 pixels, sendo este resultado 335% melhor aos frameworks avaliados

Reduced order model based on machine learning with sindy autoencoders

This work presents a numerical methodology to obtain a reduced order model – ROM – of a linear time-invariant aeroelastic model. The airfoil section of the aeroelastic model, considering only the pitch–plunge motion is studied in a fluid-structure interaction scheme using Computational Fluid Dynamics – CFD. The structural parameters of the linear mechanical system and the necessary data are taken from COMSOL Multiphysics®. In a first analysis, it is shown what is most common in current ROM approaches, a Deep Neural Network - DNN. Such a concept has a high predictive capacity, however, it becomes unfeasible for interpretation and extrapolation of the equations. The Sparse Identification of Nonlinear Dynamics – SINDy – methodology is presented. In order to show the details of the proposed technique, the SINDy technique is implemented in a sparse identification algorithm, Chaotic Lorenz system. Finally, the SINDy methodology is applied to the case of the proposed aeroelastic model. It was possible to identify the system and discover their equations with high accuracy.Trabalho de Conclusão de Curso (Graduação)Este trabalho apresenta uma metodologia numérica para a obtenção de um modelo de ordem reduzida ROM de um modelo aeroelástico invariante no tempo. A seção de aerofólio, do modelo aerolástico, considerando apenas os movimentos de translação rotação , é estudada em um esquema de interação fluido estrutura usando Dinâmica dos Fluidos Computacional CFD. Os parâmetros estruturais do sistema mecânico linear e os dados necessários são retirados do COMSOL Multiphysics®. Em uma primeira análise é mostrado o que há de mais comum nas a bordagens de ROMs atuais, uma Rede Neural Profunda DNN. Tal conceito possui elevada capacidade de predição, entretanto, torna se inviável para interpretação e extrapolação das equações. A metodologia Sparse Identification of Nonlinear Dynamics SINDy é apresentada. Inicialmente, com o objetivo de mostrar os detalhes da técnica proposta implementa se a técnica SINDy em um algoritmo de identificação esparsa, Chaotic Lorenz system. Finalmente, aplica se a metodologia SINDy para o caso do modelo aerolástic o proposto. Foi possível identificar o sistema e descobrir suas equações com alta precisão

A LEI DE RESPONSABILIDADE FISCAL (LRF) COMO INSTRUMENTO DE SUMA IMPORTÂNCIA NA CONTABILIDADE APLICADA AO SETOR PÚBLICO. UMA ANÁLISE JUNTO A CONTABILISTAS PÚBLICOS BRASILEIROS.

Pressionada por uma população cada vez mais consciente de seus direitos, reivindicante pela melhor gestão dos recursos públicos e pela transparência nessa gestão, o governo tem se visto por vezes conduzidos a posturas responsáveis na gestão fiscal, valendo-se dos dispositivos da Lei de Responsabilidade Fiscal (LRF) como balizadores da conduta largamente aceita. A pesquisa foi aplicada a diversos contadores e técnicos em contabilidade de instituições federais de ensino superior, através de questionário online disponibilizado aos pesquisados por e-mail e redes sociais. O objetivo deste trabalho é ressaltar a importância da Lei de Responsabilidade Fiscal na contabilidade aplicada ao setor público brasileiro e sua repercussão na gestão pública, bem como verificar o conhecimento que os profissionais contabilistas públicos têm da referida LRF. Através deste estudo, foi realizada uma pesquisa de âmbito exploratório e descritivo, sendo realizado levantamento bibliográfico a cerca do tema. Este trabalho revelou que a implantação da Lei de Responsabilidade Fiscal tenta promover no Brasil uma moralização e uma cultura de gestão responsável dos dinheiros públicos e que os profissionais entrevistados possuem um conhecimento razoável da supracitada Lei Complementar 101/2000, a LRF. Gradativamente e paulatinamente a LRF tem orientado àqueles que buscam a boa administração do erário público. A pesquisa foi considerada satisfatória pois foi capaz de subsidiar as análises cabíveis ao atingimento dos objetivos e a solução do problema

A poética visual no cinema de Sergio Bianchi

Trabalho apresentado no 31º SEURS - Seminário de Extensão Universitária da Região Sul, realizado em Florianópolis, SC, no período de 04 a 07 de agosto de 2013 - Universidade Federal de Santa Catarina.Este trabalho, deriva do projeto extensionista, O Cinema de Sergio Bianchi: poéticas e possibilidades, que propõe um diálogo entre o conceito de poéticas visuais nas Artes Plásticas e no Cinema, em especial, no cinema de Sergio Bianchi, o qual faz sua construção a partir do desenvolvimento de uma linguagem cinematográfica crítico-social, que tem no caos social brasileiro sua principal temática. Bianchi é detentor de um conjunto de obras provocante e polêmico, estruturado a partir de uma narrativa que trata, em especial, do tecido social de um mundo degradado e decadente, povoado por personagens encurraladas em cotidianos claustrofóbicos. Tem como objetivo principal, estabelecer a apreciação e o debate sobre os filmes de Sergio Bianchi, a partir da análise e discussão das obras, apresentadas em diferentes sessões e posteriormente discutidas com a plateia presente. As reações da plateia eram as mais diversas, ao constatarem que o que viam na tela era a reprodução de um cotidiano, muitas vezes próximos aos seus, que revelam um caos social, a partir de um cinema crítico e supostamente reflexivo. O projeto possibilitou, aos seus participantes, uma leitura ampliada de Cinema, tanto enquanto linguagem, enquanto Arte ou um produto da Indústria Cultural, estabelecendo o conceito de uma poética visual fílmica própria de Sergio Bianchi

The Scheme of Movement as an Organizer of Action in Classical and Relativistic Mechanics

This paper reports on the use of the concept of scheme as one of the references for analyzing the process of making out the meaning of relative time. It is part of the current perspective that discusses the inclusion of Modern Physics topics in high school education; the paper investigates the conditions for such inclusion to occur. To this end, a didactic sequence was produced based on the transition between the key concepts of Classical Mechanics and the Special Theory of Relativity, where one of the central points was the discussion of the influence of the reference frame in the study of motion. The research activities lasted 16 classroom hours in a third-grade year high school and were quite diverse, with lectures, group discussions, open problem-solving, and thought experiments. We analyzed, in this paper, episodes of verbal interaction and written activities of the students related to the concept of reference frame and its influence on the notion of relative time. The theoretical framework used for the analysis of the students' productions was the Theory of Conceptual Fields, which was supported by the content analysis technique. Different operational invariants were identified in the students' schema of motion and time. We concluded our research by indicating that there must be a reciprocal assimilation between the schema of time and motion for the students to be able to propose correct answers to problems in Mechanics

Episiotomia Seletiva Nos Dias Atuais: Indicações, Técnica E Associação Com Lacerações Perineais Graves

Episiotomy is a controversial procedure, especially because the discussion that surrounds it has gone beyond the field of scientific debate, being adopted as an indicator of the "humanization of childbirth". The scientific literature indicates that episiotomy should not be performed routinely, but selectively. Objectives To review the literature in order to assess whether the implementation of selective episiotomy protects against severe perineal lacerations, the indications for the procedure, and the best technique to perform it. Methods A literature search was performed in PubMed using the terms episiotomy or perineal lacerations, and the filter clinical trial. The articles concerning the risk of severe perineal lacerations with or without episiotomy, perineal protection, or episiotomy techniques were selected. Results A total of 141 articles were identified, and 24 of them were included in the review. Out of the 13 studies that evaluated the risk of severe lacerations with and without episiotomy, 5 demonstrated a protective role of selective episiotomy, and 4 showed no significant differences between the groups. Three small studies confirmed the finding that episiotomy should be performed selectively and not routinely, and one study showed that midline episiotomy increased the risk of severe lacerations. The most cited indications were primiparity, fetal weight greater than 4 kg, prolonged second stage, operative delivery, and shoulder dystocia. As for the surgical technique, episiotomies performed with wider angles (> 40°) and earlier in the second stage (before "crowning ") appeared to be more protective. Conclusions Selective episiotomy decreases the risk of severe lacerations when compared with the non-performance or the performance of routine episiotomy. The use of a proper surgical technique is fundamental to obtain better results, especially in relation to the angle of incision, the distance from the vaginal introitus, and the correct timing for performing the procedure. Not performing the episiotomy when indicated or not applying the correct technique may increase the risk of severe perineal lacerations.38630130

The space-time torsion in the context of the Exact Foldy-Wouthuysen Transformation for a Dirac fermion

In this work we focus our attention in the inconsistency that appears when the Semi-Exact Foldy-Wouthuysen transformation for the Dirac field interacting with space-time torsion field is performed. In order to solve this problem, we present a new involution operator that makes possible to perform the exact transformation when torsion field is present. Such operator has a structure, well known in the literature, composed of the product of an operator that acts in the matrices space and another one that acts in the function space. We also present the bound state of this theory and discuss the possible experimental analysis

Geometrically Complex Planar Heat Exchangers

In this study, geometrically complex planar heat exchangers, designed in line with the Constructal Law and operating at steady-state, are investigated numerically. The work is divided into two parts, one focusing on diffusion heat transfer in a rectangular plane and another on conjugate diffusion-convection heat transfer in a circular plane heat exchanger. In the first part, a heat generating rectangular solid volume made of a low conductivity material is cooled through a small, isothermal side-section of the domain. The diffusion cooling process is improved by distributing within the heat generating material a fixed amount of a high conductivity material. The question of how to best distribute the high conductivity material to cool the domain and at the same time optimize the decrease in its maximum temperature is answered via geometric optimization based on Constructal Law. The result is a T-shaped network type distribution for the high conductivity material embedded in the heat generating volume. However, this embedded approach, called here the “in-plane” distribution, is of very limited practical use for being too intrusive to the domain. An alternative proposed and investigated here is the “out-of-plane” distribution, in which the high conductivity material network is placed on top of the heat generating plane. Three different network distributions with increased complexity and same specifications (i.e., same uniform heat generation rate, planar aspect ratio and thickness of generating volume, and same volumes of base material and high conductivity material) are investigated numerically for both, in-plane and out-of-plane configurations. The main objective is to compare the heat transfer effectiveness achieved by each configuration. This aspect is very important because, if the effectiveness are comparable, the option of using the out-of-plane distribution could alleviate the practical limitations of the in-plane (embedded) configuration. An additional effort in this first part of the project is to extend the analysis to a non-dimensional parametric study, where the number of different networks is increased to six and different amounts of low and high thermal conductivity materials are investigated. This part if not only to establish if in-plane and out-of-plane yield similar results, but also to understand how the high/low thermal conductivity volume ratio influences the removal of heat out of the heat generating volume. The results, obtained numerically, show the two networks, i.e., in-plane and out-of-plane, yield nearly identical temperature distributions and heat transfer effectiveness (to within the numerical uncertainty achieved by the simulations) for all configurations tested. Hence, one can confidently use the out-of-plane networks instead of the in-plane networks in practical applications of T-shaped network cooling cold plates. The results also confirm the robustness of the thermal design and extend previous work, showing an increase in network complexity (e.g., by increasing the number of assemblies in each network) indeed yields better cooling performance, even when some of the stringent assumptions imposed in the analysis of building the networks are not fully satisfied. In the second part of the work, a heat generating material in a circular planar domain (a disk) is now cooled via convection through circular channels from the center to the periphery of the domain. The optimum distribution of the fixed volume convection channels in the domain, again following Constructal Law, yields a tree-shaped network starting with one inlet at the center of the disk, and flowing through bifurcating channels toward a set number of outlets distributed uniformly at the periphery of the disk. Here the thermal-hydraulic performance of the resulting tree-shaped flow networks is obtained numerically and compared to the simpler, radial flow networks (feeding the same number of peripheric outlets) for cooling the disc. The flow entering at the center of the disc is assumed isothermal and fully developed. Two tree-shaped flow networks are considered, having either six (one bifurcation level) or twelve (two bifurcation levels) outlets, conceived for maximizing the cooling and minimizing the flow resistance. Both, tree-shaped and radial flow configurations are set with the same disc solid and fluid (channels) volumes, and same uniformly distributed volumetric heat generation rate in the solid region. The results show the best performance flow distribution depends on factors that go beyond the channels being either radial or bifurcating, highlighting the very complex heat transfer interaction in this conjugated convection-diffusion system. Moreover, the flow separation effect intrinsic to the channel bifurcations and neglected in previous studies, is essential to the thermal design as it affect not only the overall pressure loss but also the overall heat transfer performance, particularly when the flow channel Reynolds number is high, as one would expect

Mesh motion methods for numerical aerodynamic design of lift and control surfaces

In this work, moving mesh methods based on the solution of pseudo structural and fluid problems are developed. Mesh motion methods are necessary features for numerical aerodynamic design and test of lift and control surfaces of UAVs. Here a particular moving mesh method based on a pseudo Stokes problem is compared to different well known moving mesh approaches such as techniques by solving diffusion and pseudo structural problems with prescribed velocity and displacement fields, respectively. The benchmark test for this comparison is an airfoil with a fully meshed domain, including the far field and boundary layer, over which is imposed a rotation velocity boundary condition. In order to distinguish the mesh motion methods, several mesh quality criteria are employed to determine a mesh quality mapping to identify critical regions with poor mesh quality and to access the performance of each mesh motion approach. In order to illustrate the mesh motion technology, this paper also presents results of the numerical simulation of a laminar flow over a NACA 0012 airfoil by using a numerical code based on a finite element projection method augmented with mesh motion capabilities