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Controle digital de um conversor CC-CC
Controle digital de um conversor CC-CC
Um artigo sobre controle digital de conversores CC-CC tipo buck utilizando microcontrolador STM cortex-m0+.
Ana Caroline Tondo Bonafim, Jefferson Willian França Góes, Raul Scarmosin Freitas
Evolutionary Language Development in Multi-Agent Cooperative Learning Games
Evolutionary Language Development in Multi-Agent Cooperative Learning Games
Lazaridou., et al 2017 proposed a framework for language learning that relies on multi-agent communication. The agents in the framework were setup in a referential game where they communicated about many images. In this paper, we propose an experiment where agents develop a private language for referring to specified sentences given a set of sentences. The challenge is for the agents to learn a method of distinguishing differences between sentences and to develop a shared language to be able to refer to particular sentences by those distinguishing features. We will evaluate the agents' ability to accurately identify and differentiate the sentences. In addition, we will identify patterns in the methods that the agents develop to refer to the different types of sentences.Keywords: Reinforcement learning, multi-agent coordination
Eric Tsai
SOLAR SALES ON YOUR TRIP TO MARS
SOLAR SALES ON YOUR TRIP TO MARS
We study Logarithmically Spiral Trajectories and, in particular, we look for a solution to minimize the transit time of a Spacecraft propelled by a Solar Sail, while simultaneously minimizing the area of the Solar Sail, which would allow us to carry more payload on board. We start by analyzing the forces that act on the Spacecraft taking into account that its propellant is a Solar Sail; we use the studied forces to deduce the motion equations. We then solve this motion equation with a Runge-Kutta 4 method and transform the problem of minimizing time and area to a Non-linear Optimization problem. When solving the NLP we also try to minimize the relative final speed of th spacecraft with the destination planet in order to guarantee the possibility of a safe landing on its surface. The model improves when an angle parameter α (describing the angle formed by the Solar Sail with the colliding photons) is defined as a piecewise constant function and optimized whose values are optimized in every interval to minimize transit time and Area. Using the developed model to optimize the trajectory to be followed for sending from Earth to Mars a 2000kg-spacecraft propelled by a Solar Sail, subject to the condition that at trajectory start Mars and Earth were at their closest approach, and the Arrival Relative Velocity is less than 9km/s, give us a minimal transit time of 500days and a minimal area for the Solar Sail of 183158m2, meaning that the maximal payload would be 718kg. Compared with different number of partitions of α, the optimum stays stable. This gives a solid optimal trajectory and a great result for the numerical method used. Actually, waiting until the best moment to throw the Spacecraft, id est, Mars is at 1.14 radians respectively to Earth initial position, the minimal sail area 145950 m2 and, therefore, ables to transport until 978 kg of payload with the same transit time. In addition and to conclude we tried the model to optimize the inverse trajectory.
Marco Praderio Bova, Eneko Martin Martinez, & Maria dels Àngels Guinovart Llort
Overleaf Acadêmico
Overleaf Acadêmico
Este minicurso foi (e ainda está sendo) concebido para iniciantes em LaTeX com Overleaf. Os conteúdos deste minicurso estão em uma contante evolutiva..
Francisco Reinaldo
A Cloud Optical Access Network for Virtualized GNSS Receivers
A Cloud Optical Access Network for Virtualized GNSS Receivers
Presentation at ION GNSS+ 2017. Portland, OR, Sept. 27TH. Session F2: GNSS Receiver Processing and Navigation Algorithms
Carles Fernández-Prades et al.
Een spiraal van rechthoeken rond een vierkant
Een spiraal van rechthoeken rond een vierkant
Sinds enkele jaren ben ik op zoek naar eenvoudige wiskundige en fysische problemen die onverwacht gerelateerd zijn met het getal \(\pi\). In The bouncing balls and pi beschreef ik eerder al hoe de opeenvolgende decimalen van \(\pi\) kunnen berekend worden door twee ballen volledig elastisch tegen elkaar en tegen een muur te laten botsen. In dit artikel zal ik aantonen hoe het getal \(\pi\) tevoorschijn komt door een oneindige serie rechthoeken met oppervlakte 1 spiraalsgewijze aan elkaar te kleven. In een veralgemening van dit probleem duikt op een natuurlijke wijze de gammafunctie en de formule van Stirling op.
Van den Broeck Luc
Qualificação - Reconhecimento de Cenários baseado nas Localizações dos Fornecedores do Governo Federal
Qualificação - Reconhecimento de Cenários baseado nas Localizações dos Fornecedores do Governo Federal
In most corruption scandals, the use of front companies for money laundering is almost ubiquitous. This work proposes to apply image classification to detect such organizations, through the use of Convolutional Neural Networks (CNN), namely the AlexNet architecture. The images are obtained by address search in Google Street View API, and the resulting classification will be further used along with other features to detect front com- panies in order to help the auditors from the Ministry of Transparency and Office of the Comptroller General (CGU, in Portuguese). To this moment, we applied classification to almost 15 thousand suppliers scenes with active contracts with the Brazilian Government until September 2016, obtained through data matching between the Government Purchases database and the Brazilian Federal Revenue Office database (more recent scenes should be added as this work progresses). Preliminary results with a pre-trained AlexNet CNN show the need for developing new scene classes more suited to the Brazilian context. In order to do this, we propose to apply clustering algorithms in features extracted from the last fully-connected layer of this net. The classes obtained will be used to fine-tune the AlexNet CNN for future classification, through the use of training from scratch or fine tuning techniques.
Rodrigo Peres Ferreira
Bitume ou Bocage? Zone à Défendre ! L'Histoire d'un Territoire en Lutte
Bitume ou Bocage? Zone à Défendre ! L'Histoire d'un Territoire en Lutte
Ce livret retrace l'histoire de la lutte contre le projet de l'aéroport international du Grand Ouest, à Notre-Dame-Des-Landes à une vingtaine de kilomètres au nord de Nantes, en apportant des arguments pour expliquer les raisons d'être et les motivations du mouvement de la résistance. Il est rédigé à l'origine pour accompagner le jeu de plateau coopératif "Zone à Défendre" .
Anonyme
Analyzing elliptically polarized light using Fresnel Rhomb
Analyzing elliptically polarized light using Fresnel Rhomb
The aim of the experiment is to study elliptically polarized light using a Fresnel rhomb and to determine the ratio of semi major axis to the semi minor axis of the various elliptically polarised light forms for different angles of plane polarised incidence at the rhomb
Alan Raj Jeffrey