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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
321

Identidades polinomiais graduadas e produto tensorial graduado / Graded polynomial identities and graded tensor products

Freitas, Jose Antonio Oliveira de 11 June 2009 (has links)
Orientador: Plamen Emilov Koshlukov / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Matematica, Estatística e Computação Científica / Made available in DSpace on 2018-08-14T14:50:24Z (GMT). No. of bitstreams: 1 Freitas_JoseAntonioOliveirade_D.pdf: 1578135 bytes, checksum: a3352669dd5077f0f5949766026e7bb1 (MD5) Previous issue date: 2009 / Resumo: Nesta tese estudamos identidades polinomiais graduadas para certas álgebras. Inicialmente, estudamos identidades satisfeitas pelo produto tensorial Z2-graduado. Este estudo foi motivado pelo trabalho de Regev e Seeman com produtos tensoriais Z2-graduados. Eles provaram vários casos nos qual tal produto tensorial é PI equivalente a certas álgebras T-primas. Também conjeturaram que isto sempre ocorre. Trabalhamos com os demais casos e conseguimos provar que tal conjetura e verdadeira. Alêm disso provamos que para certas álgebras, quando consideramos corpos de característica positiva, o produto tensorial graduado ainda se comporta como o não graduado. Consideramos também o produto tensorial-graduado e suas identidades. Provamos que o Teorema A B de Regev continua válido no caso do produto tensorial-graduado quando as álgebras são graduadas por grupos abelianos nitos, e é um bicaracter antissimétrico. Também estudamos a PI equivalência do produto tensorial-graduado de álgebras T-primas. Em seguida estudamos identidades graduadas, descrevemos um conjunto de geradores para as identidades Z-graduadas da álgebra de Lie W1. A álgebra W1 é a álgebra das derivações do anel de polinômios K[t], e é conhecida como a álgebra de Witt. Provamos que se a característica do corpo for 0, então as identidades Z-graduadas de W1 são geradas por um conjunto de identidades de grau 2 e 3. Mais ainda, provamos que não é possível obter um conjunto nito de geradores para as identidades Z-graduadas de W1. / Abstract: In this PhD thesis we study graded polynomial identities for certain types of algebras. First, we study polynomial identities satised by the Z2-graded tensor products. This research was motivated by the paper of Regev and Seeman about the Z2-graded tensor products. They proved that in a series of cases such tensor products are PI equivalent to T-prime algebras. Then they conjectured that this is always the case. We deal here with the remaining cases and thus conrm Regev and Seeman's conjecture. Furthermore, we prove that for some algebras we can remove the restriction on the characteristic of the base eld, and we show that the behaviour of the corresponding graded tensor products is quite similar to that for the usual ungraded tensor products. We consider too the graded tensor products and their identities where is a skew symmetric bicharacter. We show that Regev's A B theorem holds for graded tensor products whenever the gradings are by nite abelian groups. Furthermore we study the PI equivalence of -graded tensor products of T-prime algebras. Afterwards we study the graded identities of the Lie algebra W1. We describe a set of generators of the Z-graded identities of W1. The algebra W1 is the algebra of derivation of the polynomial ring K[t], and it is known as the Witt algebra. We prove that if K is a eld of characteristic 0, then the Z-graded identities of W1 are consequences of a collection of polynomials of degree 2 and 3. Furthermore we prove that the Z-graded identities for W1 do not admit a nite basis. / Doutorado / Algebra / Doutor em Matemática
322

Spolupráce mezi statickým měničem a sítí v ostrovním provozu / Cooperation between the inverter and grids in island operation

Urant, Tomáš January 2018 (has links)
This thesis deals with the creation of models of non-volatile sources connected to the power system using power converters and their connection by filter or a transformer. Furthermore, the thesis will deal with the study of the problem of connecting a large number of these sources. Another area of interest is to determine the conditions under which these sources can be used to restore network voltage after a previous outage. In the PSCAD program we will create inverter models (6 pulse, 12 pulse and one phase). In the next step, a network model will be created, where the individual sources will be connected and, in the end, we will simulate the situations. The output of the thesis is to determine the behavior of the largest number of static sources in the system and thus to contribute to the knowledge about the possibilities of safe and stable operation of non-volatile energy sources in the power system.
323

Laserový projektor / Laser Projector

Svoboda, Pavel January 2015 (has links)
The aim of this thesis is to create a system, which draws the graphics with the help of a set laser project and eventually is able to synthetize several coloured rays and thus realise a multicolour drawing. The whole system is controlled by a Raspberry PI microcomputer and the data is sent to it from a PC via an Ethernet cable. The transmission of the projector device was identified and possible ways of improving the device were suggested. The results of this thesis allow creation of a multi-coloured vector picture, transferring it into the device and depiction on the project desktop. The whole device can therefore be used for example for the purpose of a presentation.
324

Softwarově definovaná domácí automatizace / Software Defined Home Automation

Stupka, Dominik January 2016 (has links)
This thesis is about development and construction of systems for building automation. At the beginning it´s focused on usage of building automation. Short describe used topology of installation and available systems on the market. The second chapter is about designing of hardware’s elements systems. Then it’s describing control unit Raspberry Pi 3, microprocessors for communication and slave modules. For my thesis I am also engaged in interface communication and designing of I/O systems. The third and fourth chapter is describing software equipment’s of the system. The parts of microprocessor firmware and manner of control logic creating and visualization in control unit module are described in details. Last chapter contains the description of construction of testing module and measuring of system parameters.
325

Embedded zpracování videa pro dohledový systém / Embedded video processing for surveillance systems

Árva, Gábor January 2017 (has links)
Diplomová práca sa zaoberá návrhom embedded dohľadového systému, ktoré je implementované na Raspberry Pi 3 B zariadenie. Uvedený systém obsahuje algoritmy pre detekcie pohybu a detekcie objektov, ktoré sú realizované pomocou OpenCV funkcie. Vyhodnocené informácie sú prístupné na webový server.
326

Analyse de ressources pour les systèmes concurrents dynamiques / Resource analysis for concurrent and dynamic systems

Deharbe, Aurélien 21 September 2016 (has links)
Durant leur exécution, les systèmes concurrents manipulent diverses ressources dynamiques en nombre : fichiers, liens de communication, mémoire, etc. Les propriétés comportementales de ces systèmes sont alors étroitement liées aux manipulations de ces ressources qu'ils allouent, utilisent, puis détruisent. Nous proposons dans cette thèse une analyse quantitative, effectuée de manière statique, de ce type de ressources pour les systèmes concurrents et dynamiques. Les systèmes que l'on considère peuvent être des programmes concurrents et parallèles (le langage Piccolo développé dans le cadre de ce travail en est un exemple), ou encore la modélisation de systèmes plus généraux. Pour atteindre cette généricité, notre travail repose fortement sur les algèbres de processus, et plus particulièrement sur le pi-calcul pour lequel nous proposons une variante sémantique ainsi que plusieurs abstractions adaptées à l'observation des ressources en particulier. Le socle théorique de notre analyse est présenté sous la forme d'un nouveau type d'automates nominaux : les nu-automates. Ils permettent de raisonner spécifiquement sur les ressources dynamiques, tant pour caractériser les notions quantitatives de consommation en ressources que pour de futures analyses qualitatives. À partir de ce formalisme nous réalisons ensuite un ensemble d'algorithmes ayant pour but de mettre en oeuvre les résultats introduits sur les nu-automates. Enfin, nous proposons plusieurs expérimentations, sur la base d'exemples classiques du pi-calcul, de notre prototype d'analyse de ressources. / Concurrent activities involve undoubtedly many dynamic resources manupulations: files, communication links, memory, etc. Then, the behavioral properties of such systems are closely linked to their usage of those resources that they allocate, use, and finally destroy. In this work, we develop a quantitative static analysis of concurrent and parallel systems for this kind of resources. Systems that we consider can be concurrent and parallel programs (written for example in the Piccolo programming language which was developped during this thesis), or models descriptions of more general systems. To be generic, our work lies on process algebra, specifically pi-calculs for which we propose a variant semantics in addition to several resources abstractions strategies. The underlying theory is developped as a nominal automata framework (namely the nu-automata). They allow one to reason about dynamic resources usage to charaterize both quantitative and qualitative properties. From this formalism we establish an algorithmic framework that enforce the qualitative results defined on nu-automata. Finally, our resources abstractions and resources analysis are tested experimentally on classical pi-calculus examples using our prototype analysis tool.
327

Intelligente Himbeere - Der Raspberry Pi

Heik, Andreas, Sontag, Ralph 08 May 2013 (has links)
Aus der Vision, Computertechnik für den schmalen Geldbeutel technisch interessierten Jugendlichen verfügbar zu machen entstand ein kreditkartengroßer Einplatinencomputer, der Raspberry Pi. Wir möchten den Raspi im Vortrag etwas näher vorstellen und in einer kleinen Demonstration Anregungen für eigene Projekte geben. Gespannt sind wir auch auf Projekte, welche die Zuhörer bereits mit dem Raspberry Pi umgesetzt haben.
328

F.I.R.E.S.A.F.E : Automatic fire extinguisher using thermal imaging

Strömbäck, Axel, Sjöstrand, Linus January 2023 (has links)
The purpose of this bachelor’s thesis was to create a functioning turret that can recognize heat sources and automatically shoot water at them using a thermal camera and water pump. The main areas to research was the cameras capability regarding fire detection and also the turret’s efficacy in putting out fires using this detection. The reason for building FIRESAFE is to understand how technology can be implemented to improve existing fire extinguishers in a way that enables fires to be put out at an earlier stage while minimizing water damage to property. The turret is controlled using two servo motors which rotate the structure in 2-axis and a IR-camera which locates heat sources. A Raspberry Pi was used to control the software side of the project, a ultrasonic sensor for distance measurement and a basic washer pump for a car was used for the water cannon. The prototype was able to extinguish candles at a distance of 1.5m with an accuracy of 50% on the first attempt. It had an average extinguishing time of 20 seconds. / Syftet med denna kandidatuppsats var att skapa ett fungerande torn som kan lokalisera värmekällor och automatiskt släcka dessa med hjälp av en värmekamera och en vattenpump. De huvudsakliga områdena att undersöka var kamerans förmåga att upptäck eld samt tornets förmåga att släcka bränder med hjälp av eldens position. Anledningen till att bygga FIRESAFE är att förstå hur teknologi kan implementeras för att förbättra befintliga brandsläckare så att bränder kan släckas i ett tidigare stadium och minimera vattenskador på egendom. Tornet styrs med hjälp av två servo motorer som roterar strukturen i 2-axlar och värmekameran används för att upptäcka värmekällor. En Raspberry Pi användes för att styra mjukvarudelen av projektet, en ultraljudssensor för avståndsbedömning och en grundläggande spolarvätskepump från en bil användes för vattenkanonen. Prototypen kunde bekämpa ett ljus på 1.5m med en träffsäkerhet på 50% på först försöket. Det hade en genomsnittlig släckningstid på 20 sekunder.
329

Hydroponic Greenhouse: Autonomous identification of a plant s growth cycle / Hydroponiskt Växthus: Autonom identifiering av en plantas växtcykel

Håkansson, David, Lund, Anna January 2019 (has links)
In a world with an ever growing population, the ability to grow food eciently is essential. One way to improve the eciency is by automation. The purpose of this project is therefore to investigate how the identification of a plant’s stage in its growth cycle that can be made autonomous. This was done with the method of measuring the amount of green pixels in an image of the plant. To be able to answer our research questions a demonstrator was built. The demonstrator is a greenhouse with a non regulated aeroponic system, a regulation system for humidity and an identification system for determining the plant growth stage. The plant chosen to test the identification system was basil. The identification system successfully identified the stage of plants well into the adult stage, in the seed stage and in the middle of the sprout stage. It was however not always successful in the identification of plants transitioning from the sprout stage into the adult stage. / I en värld med en ständigt växande befolkning är förmågan att odla mat effektivt nödvändig. En metod för att öka denna effektivitet är genom automatisering. Syftet för detta projekt är därför att undersöka hur identifieringen av en plantans stadie i dess växtcykel kan automatiseras. Detta gjordes genom att mäta antalet gröna pixlar i en bild av plantan. För att kunna svara våra forskningsfrågor byggdes en testmiljö. Testmiljön bestod av ett växthus med ett oreglerat aeroponiskt system, ett regulationssystem för luftfuktighet och ett identifikationsssystem för att avgöra en plantas stadie i dess växtcykel. Plantan som valdes för att testa identifikationssystemet var basilika. Identifikationssystemet som togs fram kunde med framgång identifiera stadiet av en planta som är långt in i dess vuxna stadie, i förstadiet eller i mitten av dess groddstadie. Plantor som precis övergått från grodd till vuxet stadie blev däremot inte alltid identifierade korrekt.
330

Home Care Logistics: A Monitoring System with a Communication Unit for the Elderly / Hemtjänstlogistik: Övervakningssystem med kommunikationsenhet för Aäldrevården

Zec, Kenan, Hansson, Sofia January 2019 (has links)
Humans are growing older which presents challenges for the health care system. One solution for allowing individuals to continue living in their home, despite age related dif- ficulties, is a sensor based surveillance system. These systems can monitor a number of parameters, for example motion or temperature. If certain limits are exceeded the sys- tem can notify family members or health care services. The aim of this project was to build a prototype of such a system which also had to be cheap and easy to install and maintain. The final prototype consists of a motion detection sensor in the bathroom, a temperature sensor around the kitchen stove and a temperature sensor for measurement of ambient room temperature. Each sensor is connected to its own Arduino and they are all programmed with different limits. The sensors communicate wirelessly with a central hub through the communication protocol LoRa. Once the central hub, which consists of a Raspberry Pi, receives a LoRa signal it sends an email to a chosen address. / Människor blir allt äldre vilket är en utmaning för sjukvården. En lösning som tillåter individer att fortsätta bo i sina hem, trots åldersrelaterade svårigheter, är ett sensorba- serat övervakningssystem. Sådana system kan övervaka ett flertal parametrar, exemåelvis rörelse eller temperatur. Om vissa gränser överskrids kan systemet underrätta anhöriga eller hemtjänsten. Syftet med det här projektet var att bygga en prototyp av ett sådant system, som även skulle vara billig och enkel att installera och underhålla. Den slutgiltiga prototypen består av en rörelsedetektor i badrummet, en temperatursensor vid köksspisen och en sensor som mäter den omgivande temperaturen i ett rum. Varje sensor är kopp- lad till en egen Arduino och de är alla programmerade med olika gränsvärden. Sensorerna kommunicerar trådlöst med en centralenhet genom kommunikationsprotokollet LoRa. När centralenheten, som består av en Raspberry Pi, tar upp en LoRa-signal skickar den ett email till en vald adress.

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