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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.
31

Prototyputveckling av digitalt styrsystem för torkskåp

Hermansson, Lena, Pettersson, Christian January 2005 (has links)
Nimo Verken AB is the leading producer in the Scandinavia of drying cabinets. The construction has, with small changes, been the same since the 70s with a thermostat and a timer as controlling system. There was a wish to develop a modern cabinet which showed remaining time on a display and with energy saving functions. In this report we go through how it is possible to implement a digital controlling system, where remaining time is shown on a display and where it is possible to choose a preset “program”. The report first presents the fundamental theory for a PIC, where we describe the different registers, how interrupts are handled, the internal clock function and how data is sent to control the different parts of the construction. Next the report presents and describes the new hardware that is needed, such as the encoder, the temperature sensor and the display. After the theory we describe how the program in the PIC may be drafted. Last in the report we have the result of the tests of the temperature variations and the accuracy of the time.
32

Particle-In-Cell Method To Predict Plasma Behavior Between Two Plates

Tsai, Jie-Cheng 09 August 2011 (has links)
This study uses the PIC (particle-in-cell) method to simulate unsteady three-dimensional behavior in argon plasma under low pressure , low density between two plates. Plasma has been widely used in materials processing, film manufacturing, nuclear fusion , light source , etc. It is therefore important to study Plasma behavior . This model ignores secondary electron emission , recombination between ions and electrons and assumes a uniform distribution of the neutrals having velocity of a Maxwellian distribution. The lower plate in subject to a biased voltage and magnetic field. The result show the effects of a biased voltage in density and velocity of the ion and electron with the low plate.
33

Using PIC Method to Predict Transport Variables in Plasma Near an Electrically Biased Surface

Huang, Chih-tsai 09 August 2009 (has links)
This study uses the PIC (Particle-in-cell) method to simulate unsteady three-dimensional transport variables in argon plasma under low pressure and weak ionization between two planar electrodes suddenly biased by a negative voltage. Plasma has been widely used in etching, ion implantation, light source, and encountered in nuclear fusion, etc. Studying transport processes of plasmas therefore is important. This work ignores magnetic field, secondary electron emission, recombination between ions and electrons, and assumes a uniform distribution of the neutrals having velocity of a Maxwellian distribution. Accounting for elastic collisions between electrons and neutrals, ions and neutrals, and inelastic collisions resulting in ionization from impacting neutrals by electrons, and charge exchange between ions and neutrals, the computed results in this work quantitatively show non-isotropic pressures, shear stresses and heat conduction of the ions across the sheath to the surfaces suddenly biased by a dc negative voltage.
34

HomeBT : För ett intelligentare hem

Wärja, David, Pettersson, Joakim January 2002 (has links)
<p>Frysar som känner av om dörren står öppen och spisar som registrerar värmeplattornas temperatur och inkopplingstid och vid fara larmar bostadsinnehavaren. De så kallade intelligenta konsumentprodukterna kommer i en snar framtid ersätta många av dagens ”dumma” apparater. Intelligensen skulle emellertid enkelt kunna kopplas till befintlig apparatur utan att något ingrepp i hårdvaran behöver göras. Baserat på en patentsökt idé av Niclas Fock på Combitech Systems har ett system konstruerats, som på ett snabbt, enkelt och kostnadseffektivt sätt möjliggör smarta produkter redan idag.</p> / <p>Cabinet freezers that can sense if the frontdooris unproperly closed and stoves registering temperature and usage time of the plates, alerting the house owner when danger occurs. These so called intelligent consumer products will in a nearby future replace many of todays ”dumb” devices. But intelligence could be applied on existing apparatus without changing its hardware. Based on a idea (pending patent) by Niclas Fock at Combitech Systems a system is designed. This system will in a rapidly, simple and cost effectively manner realise smart products already today.</p>
35

SMS-baserat alarm med positionering : GPS based alarm with positioning

Nors, Niclas, Rehnström, Tom January 2008 (has links)
<p>The study investigates how to design a low-cost, versatile event messaging system using SMS. A typical use case is a fire alarm or intrusion detector when equipped with appropriate sensors. With a GPS receiver connected, the actual position is included in the message, allowing for use as theft alarm in e.g. a car or in mobile home.</p> / <p>Studien undersöker hur man kan konstruera ett billigt, mångsidigt meddelandesystem som använder SMS. Ett exempel på användningsområde är brandlarm eller inbrottslarm med motsvarande sensorer anslutna. Även positionen kan förmedlas med en GPS ansluten, och då finns även möjligheten att använda enheten som stöldlarm för till exempel bil eller husvagn.</p>
36

An Electronic Control Architecture for a Photonic Integrated Circuit

Gemma, Luca 14 April 2023 (has links)
Quantum computing is rapidly growing as well as the interest in it, not only by the scientific community but also by impacting realities such as IBM and Microsoft, which are aiming to be the first to acquire quantum supremacy, a meaningful theoretical step in quantum research where a quantum computer would win undisputed once and for all the race with traditional supercomputers. One of the main enabling technologies for quantum computing is photonics, that features photons as the quantum actors "interacting" in a PIC, mostly based on the mature silicon technology of electronics. This thesis presents my work on electronic control architecture for PICs. The work is based on PICs fabricated in Fondazione Bruno Kessler (FBK) with silicon and dielectric technology, using silicon oxynitride (SiON) as the wave-guiding dielectric medium. The PIC were integrated on Printed Circuit Boards through wire-bonding technique, realizing modules easily integrated and re-configured with the custom made interposer board and the multiple voltage drivers that are at the core of the electronic architecture. Then, both the thermistors and the photodiodes were characterized. A custom firmware was then developed to control the thermistors by providing an analog voltage in the 0-12 V range, and each of those elements effectively acts as a Degree of Freedom (DoF) for the photonic architecture. In addition, to validate the results obtained by voltage driving the phase-shifters, the theoretical output of a single Mach Zehnder Interferometer (MZI) was computed and compared to the one achieved experimentally. Furthermore, such systems are controlled in a closed loop by using as a feedback the photocurrent produced by photodiodes placed either on each output of the PIC or homogeneously integrated withing the PIC itself. Finally, a secondary source of feedback was developed and investigated. Although it is a feasible method to estimate the light intensities of outputs, basing the feedback on invasive sensors implies strict bindings during the design stage and limits the measurable scenarios of a PIC, thus in this thesis I also propose an optical tool to arbitrary tune and control a PIC based solely on camera inspection. By using such technique it would be possible not only to achieve comparable results with respect to the traditional invasive sensing, but also to inspect the system configuration in any section of the chip, without being limited to only the regions where photodiodes would be present.
37

Développement d'une source pulsée d'électrons extraits d'un plasma produit par laser / Development of a pulsed source of electrons extracted from a laser produced plasma

Raymond, Xavier 24 September 2018 (has links)
Ce manuscrit de thèse décrit le développement d'un faisceau d'électrons intense et bref qui s'insère dans le cadre de la recherche sur les propriétés nucléaires de la matière au sein des plasmas chauds et denses. Afin d'obtenir un tel faisceau, une nouvelle source a été imaginée, dont le principe est basé sur l'extraction des électrons d'un plasma produit par une impulsion laser intense. La caractérisation du plasma produit par laser lors de son expansion fait l'objet d'une première partie expérimentale de ce manuscrit. Ensuite, une différence de potentiel électrique de l'ordre de quelques kV appliquée sur le plasma lors de son expansion montre que l'extraction des électrons est un processus dynamique. Ces observations expérimentales sont validées par des études numériques à l'aide du code de simulation Particle-In-Cell "XOOPIC". Enfin, les distributions en surface et en énergie des électrons extraits du plasma sont déterminées expérimentalement et numériquement tout au long de l'expansion du plasma, ce qui fait l'objet d'une ultime partie de ce manuscrit. Pour cela, un détecteur de type Faraday Cup est utilisé. Une analyse de l'intensité d'émission du courant d'électrons via un modèle numérique met en évidence la présence d'un pré-plasma fournissant un champ électrique extracteur supplémentaire. / This Ph.D thesis describes the development of an intense and brief electron beam and forms part of the research on the nuclear properties of matter in hot and dense plasmas. In order to obtain such a beam, a new source has been created, the principle is based on the extraction of electrons from a plasma produced by an intense laser pulse. The characterization of the laser-produced plasma during its expansion is the subject of a first experimental part of this thesis. Then, an electrical potential of the order of a few kV applied to the plasma during its expansion shows that the extraction of the electrons is a dynamic process. These experimental observations are validated by numerical studies using Particle-In-Cell simulation code "XOOPIC". Finally, the surface and energy distributions of the electrons extracted from the plasma are determined experimentally and numerically throughout the plasma expansion, which is the final part of this thesis. For this, a Faraday Cup type detector is used. An analysis of the emission intensity of the electron current with a numerical model shows the presence of a pre-plasma providing an additional extracting electric field.
38

Modeling of the negative ion extraction from a hydrogen plasma source : application to ITER neutral beam injector / Modélisation de l'extraction d'ions négatifs d'une source de plasma d'hydrogène : application à l'injecteur de neutres d'ITER.

Mochalskyy, Serhiy 20 December 2011 (has links)
Le développement de la source d'ions négatifs pour l’injecteur de particules d’ITER constitue une des étapes essentielles pour générer des neutres de haute énergie . Pour remplir les caractéristiques requises pour ITER en termes de chauffage et de courant à l'intérieur du réacteur principal, la source d'ions négatifs doit délivrer 40A de D-. La création d'une telle source représente un défi tant technique que scientifique et demande une meilleure compréhension des phénomènes physiques impliquées . Les connaissances actuelles sur le méchanisme d'extraction d'ion négatifs d’un plasma électronégatif sont limitées, spécialement concernant la compréhension des caractéristiques d'une gaine de plasma magnétisé dans la région d’intérêt où on constante également l’extraction des électrons simultanément avec les ions négatifs qui. De plus, l'asymétrie due à la configuration croisée du champ magnétique pour piéger les électrons nécessite une étude du problème en trois dimensions. Un code 3D Particle-In-Cell électrostatique a été spécialement développé pour étudier ce problème. Le code utilise les coordonnées cartésiennes et peut prendre en compte des géométries complexes. Le code nommé ONIX étudie les propriétés du plasma et le transport des électrons et des ions négatifs au niveau de la zone d'extraction. Les résultats sur la formation d'un ménisque de plasma et l'écrantage du champ d'extraction par ce plasma, ainsi que les trajectoires des ions négatifs, sont présentés. L'efficacité de l'extraction d'ions négatifs du volume et de la surface est investiguée et on trouve que les processus de création en surface des ions négatifs jouent un rôle capital. / The development of the negative ion source constitutes a crucial step in the construction of the neutral beam injector of ITER. To fulfil the ITER requirements in terms of heating and current drive, the negative ion source should deliver 40 A of D-. The achievement of such a source is challenging from technical and scientific points, and it requires a deeper understanding of the underlying physics. The present knowledge of the ion extraction mechanism from the negative ion source is limited due to the complexity of the problem that involves the comprehension of the behaviour of magnetized plasma sheaths when negative ions and electrons are pulled out from the plasma. Moreover, due to the asymmetry induced by the crossed magnetic configuration used to filter the electrons, any realistic study of this problem must consider the three spatial dimensions. To address this problem in a realistic way, a 3D Particles-in-Cell electrostatic code specifically designed for this system was developed. The code uses Cartesian coordinate system and it can deal with complex boundary geometry as it is the case of the extraction apertures. The complex magnetic field that is applied to deflect electrons is also taken into account. This code, called ONIX, was used to investigate the plasma properties and the transport of negative ions and electrons close to a source extraction aperture. Results on the formation of the plasma meniscus and the screening of the extraction field by the plasma are presented here, as well as negative ions trajectories. Negative ion extraction efficiency from volume and surfaces was investigated showing the capital importance of the surface negative ion production.
39

Monitoring a řízení teplovodních ventilů regulace vytápění jednočipovým mikropočítačem / Monitoring and controlling of the heating water valves by smart board microcomputer

MAŠEK, Roman January 2013 (has links)
The Masters thesis describes the control of heating system in family houses where exists requests for supervising and measuring of sources, energy storages and delivery parts of network. Description includes detail for source education support, overviews to development tools and programming language for microcontrollers. Heating system is built for two sources of energy and every source is steered alone. Source codes are designed into PIC? single-chip processors PIC? 18F4520 and PIC? 16F628A developed by Microchip company. These are deployed in unified boards called embedded board chosen for their accessibility from point of view low and high voltage interfaces. Part application of powerful elements control describes principle of operation and their usage in networks. For on-line control of central equipment is preferred usage of powerful components with servo-mechanism and for simpler usage is good to use passive components. Temperature sensor read current value in cross points of network where are media mixed or saved. Processors provides except own control jobs information interface for users too. Used SW is well arranged, faithful and includes routine for source code optimizing. The example of controlled system is actuators in family house heating with high and low temperature circuits which are controlled by industrial systems as current gas coopers.
40

RASTREABILIDADE BOVINA UTILIZANDO IDENTIFICAÇÃO POR RADIOFREQUÊNCIA EM PECUÁRIA DE PRECISÃO MODELO TEÓRICO / BOVINE TRACEABILITY USING RADIOFREQUENCY IDENTIFICATION IN PRECISION LIVESTOCK THEORETICAL MODEL

Borne Junior, José Ayrton de Souza 09 January 2015 (has links)
This paper presents a theoretical model of electronic technology applied to Precision Farming and becomes a grant to further increase the use of Precision Farming, setting that is transforming the way you get the results from the works in the field. The design of a radio frequency identification system, currently known as RFID, to be used in the identification and traceability of cattle is the goal to be achieved. It seeks initially emphasize the definition and the use of the use of Precision Farming as a routine in the activities of the field in Brazil. How is the cattle industry and the Precision Farming definition are important items to achieve the proposed goal. The SISBOV system and traceability are presented, showing its importance, but not the obligation deployment along to landowners who work with the creation and marketing of cattle and their meat products. Shows the definition of microprocessors and microcontrollers, their internal architectures and all the associated peripherals to them and is also shown as the definition of embedded systems has made a revolution in the design of these. Plot a marketing scenario and use of electronic products in the Brazilian commercial sphere, indicating how the delay in using technology more turns in the electronics consumers than in technology trainers. Emphasizes in the principle of operation of RFID systems and which the communication protocols that are used. The reader RFID design and miniaturization of electronics has enabled the creation of a device with surface mount technology decreasing the dimensions of the printed circuit board and allowing the reduction of cost in the design of this system. We present all the peripherals that make it up and the way they connect with the master processor, including the slave processor which performs the digital input and output functions and the keyboard. Communication protocols and flowcharts show the use of known commercial channels in using software. The use of solar energy is presented as an alternative source of electric power supply in the operation of the reader equipment. The high cost of commercial RFID modules prevented the practical implementation of the system. / Este trabalho apresenta um modelo teórico da tecnologia eletrônica aplicada à Pecuária de Precisão e transforma-se em um subsídio a mais para incrementar o uso da Agricultura de Precisão, definição que está transformando a maneira como se obtém os resultados advindos do trabalho no campo. O projeto de um sistema de identificação por radiofrequência, conhecido atualmente como RFID, a ser utilizado na identificação e rastreabilidade de gado bovino é o objetivo a ser alcançado. Procura-se inicialmente enfatizar a definição e a utilização do uso da Agricultura de Precisão como uma rotina nas atividades do campo no Brasil. Como está à atividade pecuária e a definição de Pecuária de Precisão são itens importantes para alcançar o objetivo proposto. O sistema SISBOV e a rastreabilidade são apresentados, mostrando a sua importância, mas não a sua obrigação de implantação junto aos proprietários rurais que trabalham com a criação e comercialização de gado e seus produtos cárneos. Mostra-se a definição de microprocessadores e microcontroladores, suas arquiteturas internas e todos os periféricos associados a eles e também é mostrado como a definição de sistemas embarcados tem realizado uma revolução no projeto destes. Traça-se um cenário da comercialização e uso de produtos eletrônicos na esfera comercial brasileira, indicando como o atraso no uso da tecnologia nos transforma muito mais em consumidores de produtos eletrônicos do que em formadores de tecnologia. Enfatiza-se o princípio de funcionamento de sistemas RFID e quais os protocolos de comunicação que são utilizados. O projeto do leitor RFID e a miniaturização da eletrônica possibilitou a criação de um equipamento com tecnologia de montagem em superfície diminuindo as dimensões da placa de circuito impresso e possibilitando a diminuição do custo no projeto deste sistema. Apresentam-se todos os periféricos que o compõem e a maneira como se interligam com o processador mestre, inclusive o processador escravo o qual executa as funções de entrada e saída digitais e o teclado. Protocolos de comunicação e fluxogramas evidenciam a utilização de canais conhecidos comercialmente na utilização de software. O uso da energia solar apresenta-se como uma alternativa de fornecimento de alimentação elétrica no funcionamento do equipamento leitor. O alto custo dos módulos RFID comerciais inviabilizou a parte prática do sistema.

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