In 1865 Maxwell outlined the theoretical framework for electromagnetic field propagation. Since then many important developments have been made in the field, with an emphasis on systems using high frequencies for long-range interactions. It was not until recent years that applications based on short-range inductive coupling demonstrated the advantages of using low frequency transmissions with magnetic fields to transfer power and information. This thesis investigates magnetic transmissions in the near-field and the possibility of producing induced voltages in printed circuit boards. A near-field magnetic induction system is designed to generate a magnetic flux in the very low frequency region, and used experimentally to evaluate circuit board induction in several interesting environments. The resulting voltages are measured with digital signal processing techniques, using Welch’s method to estimate the spectrum of the received voltage signal. The results show that the amount of induced voltage is proportional to the inverse cube of the transmission distance, and that the system is able to achieve a maximum induced voltage of 65 \micro V at a distance of 2.5 m and under line-of-sight conditions. It is also concluded that conductive obstructions, electromagnetic shielding and background noise all have a large impact on the obtained voltage, either cancelling the signal or causing it to fluctuate.

Submitted by Liliane Ferreira (ljuvencia30@gmail.com) on 2018-05-22T11:52:48Z No. of bitstreams: 2 Dissertação - Francisco Messias Gomes Barros - 2018.pdf: 8771335 bytes, checksum: 8ab2ae9e511e04979d246738a58a8352 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2018-05-22T12:15:21Z (GMT) No. of bitstreams: 2 Dissertação - Francisco Messias Gomes Barros - 2018.pdf: 8771335 bytes, checksum: 8ab2ae9e511e04979d246738a58a8352 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-05-22T12:15:21Z (GMT). No. of bitstreams: 2 Dissertação - Francisco Messias Gomes Barros - 2018.pdf: 8771335 bytes, checksum: 8ab2ae9e511e04979d246738a58a8352 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2018-04-24 / The work covered the First National Congress of Intellectuals, held in Goiânia in February, 1954. The research had as central objective to understand to which degree this event, organized by the PCB, can be considered critical to the current hegemonic culture, represented by the State, since the meeting privileged as a centel theme the defense and preservation of the “national culture”. The preparatory mobilization of the Congress involved the drafting of a manifesto, which sought to "preserve the national character of our culture," signed by 1,082 intellectuals from Brazil. To the event about 300 participants showed up, from diferente brazilian states, and nine foreign delegations, including Chile, whose main star was the poet Pablo Neruda. Following this tone, the following secundary objectives were adopted: Highlight that the Congress was inserted in the PCB’s strategy of trying an inflection in its cultural dogmatism, marked by the dispute of comand of the Brazilian Association of Writers (ABDE); to establish a correlation between culture and politics, taking as reference the resolutions of the meeting and to evaluate the possible contributions bequeathed by this event. The qualitative study used as a technical procedure bibliographical and documentary research, and as a method of data analysis, content analysis. It was intended to demonstrate that the generic concept of "national culture" resulted in guidelines and resolutions that configurated the outline of a critical and alternative cultural policy, or according to the Gramscian concept, a counter-hegemony, capable of counteracting the culture of the hegemonic system. / O trabalho abordou o I Congresso Nacional de Intelectuais, que se realizou em Goiânia, em fevereiro de 1954. A pesquisa teve como objetivo central buscar compreender em que medida esse evento, organizado pelo PCB, pode ser considerado crítico à corrente cultural hegemônica, representada pelo Estado, uma vez que o conclave privilegiou como temática central a defesa e preservação da “cultura nacional”. A mobilização preparatória do Congresso envolveu a redação de um manifesto, que concitava “preservar o caráter nacional de nossa cultura”, assinado por 1.082 intelectuais do Brasil. Ao evento compareceu cerca de 300 participantes, de diferentes Estados brasileiros, e nove delegações estrangeiras, incluindo a do Chile, cuja principal estrela foi o poeta Pablo Neruda. Seguindo esse diapasão, adotaram-se os seguintes objetivos secundários: evidenciar que o Congresso estava inserido na estratégia do PCB de tentar uma inflexão no seu dogmatismo cultural, marcada pela disputa do comando da Associação Brasileira de Escritores (ABDE); estabelecer uma relação entre cultura e política, tomando como referencial as resoluções do conclave e avaliar as possíveis contribuições legadas por esse evento. O estudo, de abordagem qualitativa, utilizou como procedimento técnico as pesquisas bibliográfica e documental, e como método de análise de dados a análise de conteúdo. Pretendeu-se demonstrar que o conceito genérico de “cultura nacional” resultou em diretivas e resoluções que configuraram o esboço de uma política cultural crítica e alternativa, ou segundo o conceito gramsciano, uma contra hegemonia, ou seja, uma contraposição à cultura do sistema hegemônico.

A produção artística de Patrícia Galvão possui uma matriz política na qual a teoria e a prática comunista se entrelaçam à experiência modernista. Confrontada com a trajetória da autora, a estrita consonância de seu livro de estreia com as palavras de ordem do PCB nos permite reconhecer e avaliar tensões, conflitos e impasses da esquerda brasileira. A figuração do outro, no caso, o proletariado emergente pós-revolução de 1930, e as dificuldades do escritor, ou intelectual, em lidar com esta matéria são chaves importantes de nossa análise. O estudo de Parque industrial (1933), tanto de suas características internas quanto de seu lugar na história do modernismo brasileiro, ocupa a maior parte desta dissertação. / Patrícia Galvão\'s artistic work has a political framework in which communist theory and practice are intertwined with the modernist experience. Taking into consideration the author´s trajectory, the strict correspondence between her first book and PCB\'s watchwords allows us to recognize and evaluate tensions, conflicts and dilemmas of the Brazilian left-wing. The figuration of the other, in this case, the emerging proletariat after the 1930 revolution, and the difficulties faced by the writer, or intellectual, in dealing with this matter play a key role in our analysis. The study of Parque industrial (1933), both in its internal characteristics and in its place in the history of Brazilian modernism, occupies most of this work.

This thesis project aims to develop an active Radio Frequency Identification tag (RFID) which uses an interesting method for positioning and ID detection. In this project, rather than classical ways of positioning methods such as triangulation or radio maps, infrared light and a camera with an infrared filter was used for the positioning. Tag identification detection is done by applying image analysis on camera images. When a specific part is wanted from the warehouse, this part is addressed through the active RFID system and the tag attached to that part starts to blink with the tag ID. A camera with an infrared filter above the goods in the ceiling finds the blinking infrared led, detects the tag’s position by image analysis, and confirms the ID with the requested ID number. A led transmitting visual light is used to ensure the tag also can be seen by the forklift driver in the warehouse environment when he is in close range of the part. First of all, related work and scientific papers were examined mostly from the IEEE database, which was instrumental in constructing this thesis project. Under the circumstances of low power consumption and the demands from the tag, additional possible components for an RFID tag such as an infrared led, a visual led, transistors for the LED amplifier stage and an LDO (Low-dropout) voltage regulator are chosen. Necessary technical calculations such as gain, power consumption are calculated. The RFID tag is built with these components, and transferred into the software environment .First the schematic is drawn and footprints created for the each component and the case styles are decided for transferring the circuit into the layout environment. For the radio circuit part which is used for the communication between the server and the tag, transmission lines of PCB demands are examined and the necessary calculations are made for impedance matching to prevent any disorder. After preparation of the PCB, gerber files are sent for the manufacturing process and the hardware part is completed. The components are mounted and the LED’s blinking time interval is set depending on the camera’s applicable frame speed, relevant tests for the ID detection and positioning (see fig.1). With optimisation of the time interval for recognition of the ID, an algorithm for the positioning of the RFID tag is developed and the related ID detection algorithm is developed for the real time applications by using a camera. As a result of this thesis project, instead of using complex systems for the positioning, such as triangulation or creating a radio map with multiple readers etc. a basic solution is produced as an alternative.  The efficiency of the system, the distance that allows the positioning and how applicable the system is are examined.

La contamination des sols et sédiments par les polychlorobiphényls (PCB) pose un problème sanitaire et environnemental à l’échelle mondiale, en raison de la récalcitrance et de la toxicité de ces composés. L’objectif de cette thèse est de chercher un procédé de remédiation de sédiments contaminés aux PCB en utilisant le fer zérovalent (Fe0). D’abord, une campagne de prélèvement a été menée sur des sites contaminés par le recyclage des déchets électroniques en Chine du sud. La contamination en PCB n’était pas aussi forte que prévue, mais la présence de métaux lourds accentue la difficulté de la remédiation. Ensuite, a été étudiée la déchloration des PCB par le Fe0 en solution aqueuse, en présence de métaux et surfactants. Les résultats ont montré la déchloration progressive des PCB et révélé l’itinéraire réactionnel avec la spécificité des congénères et la régio-spécificité. L’importance relative des facteurs qui influent se classe selon : tensioactif > acide humique > pH > Ni2. La décontamination du sédiment a été étudiée par 1) lavage avec une solution aqueuse de tensioactif suivie de la déchloration des PCB en solution et 2) mélange direct avec le Fe0 et les tensioactifs. La seconde approche s’est avérée prometteuse pour la remédiation / Soil and sediment contamination by polychlorinated biphenyls (PCBs) is a global health and environmental concern, since PCBs are toxic and recalcitrant. The aim of this thesis is to find a remediation process to PCBs contaminated sediments by using zerovalent iron (ZVI). To begin the studies on remediation, a survey was conducted on sites contaminated by e-waste recycling activities in south China. PCBs contamination was not as severe as previously, whereas the co-existence of PCBs and heavy metals increases the difficulty of remediation. Afterwards, the feasibility PCBs degradation by ZVI in aqueous solutions was investigated. Results confirmed the stepwise dechlorination of PCBs by ZVI and the major pathway with congener specifity and regiospecifity. The relative importance of the influential factors to ZVI degradation of PCBs was in the order of surfactants > humic acid > pH > Ni2+. Sediment decontamination was studied by 1) washing with an aqueous solution of surfactant followed by ZVI dechlorination of PCBs and 2) direct mixing with ZVI and surfactant solution. The second approach gave promising results for remediation

This diploma thesis deals with the design and realization of robotic drive of the camera scanner system of plants together with the control unit. This device serves as the carrier system of various camera sensors. The sensors will monitor both the growth and the physiological status of the cultivated plants in the growth chambers. The thesis describes the choice of electronic and mechanical components from which the device is built. The text describes a design of the PCB that will control the device. Part of the thesis is also a demonstration of the realization of the systém together with the illustration of the real form of the system and its testing.

Tato práce se zabývá výběrem vhodného obrazového snímače pro použití v kameře snímající rostliny ve vysokém rozlišení a návrhem vhodného obvodu pro propojení vybraného snímače (SONY IMX253) s vývojovou deskou Avnet MicroZed. Tato práce pojednává o jednotlivých parametrech obrazových snímačů podle kterých je vybírán vhodný obrazový snímač. Je vysvětlen proces výběru vhodného obrazového snímače a podrobněji popsány parametry vybraného snímače. Je naznačena problematika návrhu elektroniky a plošných spojů z hlediska požadavků vysokorychlostních obvodů a citlivých a specifických součástek jako je obrazový snímač. Je nastíněna konfigurace a programování obvodu Xilinx Zynq a nakonec je provedeno zjednodušené teoretické ověření funkčnosti navrženého modulu.

Táto práca sa zaoberá vývojom, testovaním a implementáciou adaptívneho riadiaceho systému pre dvojkolesové samobalancujúce vozidlo. Adaptácia parametrov vozidla sa uskutoční na základe parametrov vodiča. Parametre sústavy sa nemerajú priamo, ale sú odhadované na základe priebehu stavových premenných a odozvy sústavy. Medzi odhadované parametre patrí hmotnosť a poloha ťažiska vodiča. Cieľom práce je zabezpečiť adaptáciu jazdných vlastností vozidla k rôznym vodičom s rôznou hmotnosťou, kvôli zlepšeniu stability vozidla. Táto práca je pokračovaním predchádzajúcich projektov z roku 2011 a 2015.

This diploma thesis deals with a design and implementation of an embedded device (module), used to control a robotic manipulator. The module instructs servomotors of the manipulator to move according to the commands received via USB interface. The module consists of two double-sided printed circuit boards. The first one allows connection to the CAN bus, redundant and thus reliable power supply for servomotors as well as the whole module. The second board, compute oriented one, embeds powerful microcontroller used to communicate with the servomotors and to solve the kinematics tasks. As a part of the thesis a graphical user interface as well as a web-oriented interface were developed. Both interfaces allow full control of the manipulator. All the communicating buses, tools and methods used during the design and implementation phases of the work are described in the thesis. Finally, measurements proved improvement of the motion smoothness and response times in several orders of magnitude in comparison to the previous system.

Tato diplomová práce se zabývá revizí elektroniky robotického vozidla car4 se zaměřením na měření rychlosti otáčení kol, výkonovou a řídicí elektroniku. Car4 posloužilo jako základ pro již přes 20 diplomových prací od roku 2010. To znamenalo, že některé základní aspekty car4 byly zastaralé. Bylo vytvořeno schéma elektroniky vozidla, které bylo dále využito pro vývoj a výrobu nového hardwaru. Komponenty byly poté otestovány a implementovány na vozidlo. Dále byl vytvořen kinematický model 4WS vozidla za použití Ackermanovy geometrie, který byl implenetován a otestován na car4. Dále by měl sloužit jako základ řídicího algoritmu pro budoucí vývoj car4.