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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.
11

Cylinder-by-Cylinder Torque Model of an SI-Engine for Real-Time Applications / Cylinderindividuell Momentmodell för Realtidstillämpningar

Hashemzadeh Nayeri, Mohit January 2005 (has links)
In recent years Hardware-in-the-Loop HiL, has gained more and more popularity within the vehicle industry. This is a more cost effective research alternative, as opposed to the tests done the traditional way, since in HiL testing the idea is to test the hardware of interest, such as an electronic control unit, in a simulated (or partially simulated) environment which closely resembles the real-world environment. This thesis is ordered by Daimler Chrysler AG and the objective of this thesis is the developing of a cylinder-by-cylinder model for the purpose of emulation of misfire in a four-stroke SI-engine. This purpose does not demand a precise modelling of the cylinder pressure but rather an adequate modelling of position and amplitude of the torque produced by each cylinder. The model should be preferebly computaionally tractable so it can be run on-line. Therefore, simplifications are made such as assuming the rule of a homogenous mixture, pressure and temperature inside the cylinder at all steps, so the pressure model can be analytical and able to cope with the real-time demand of the HiL. The model is implemented in Simulink and simulated with different sample rates and an improvement is to be seen as the sample rate is decreased.
12

Steering System Verification Using Hardware-in-the-Loop / Verifiering av ett styrsystem genom Hardware-in-the-loop

Bjelevac, Salko, Karlsson, Peter January 2015 (has links)
In order for leading industrial companies to remain competitive, the process of product developement constantly needs to improve. In order to shorten development time -- that is the time from idea to product -- simulations of products in-house is becoming a popular method. This method saves money and time since expensive prototypes become unnecessary. Today the calibration of steering gears is done in test vehicles by experienced test drivers. This is a time consuming process that is very costly because of expensive test vehicles. This report investigates possibilities and difficulties with transfering the calibrations from field to rig. A steering rig has been integrated with a car simulation program. Comparisons between simulation in the loop (SIL) and hardware in the loop (HIL) have been made and differences between different configurations of steering gears have been evaluated. An automatic process including calibration of parameters, testing and analysis of the test results has been implemented. The work laid the foundation of calibration of steering parameters and showed correlation between calibration parameters and objective metrics.
13

Photooxidation of ascorbate as a substitute for oxygen production by illuminated chloroplasts

Zaugg, Waldo S. 01 April 1961 (has links)
The ability of freshly prepared spinach or poke weed (Phytolacca americana) chloroplasts to photoreduce triphosphopyridine nucleotide (TPN) under anaerobic conditions decreased in the presence of ascorbate and 2,6-dichlorophenolindophenol (DPIP). On .aging the chloroplasts, however, addition of DPIP and ascorbate was required for a high rate of TPN photoreduction. Qualitatively similar results were obtained for photoreduction of DPN, indigo carmine, riboflavin-5'-phosphate and vitamin K3 . Addition of 3-(3,4-dichlorophenyl)-1,l-dimethylurea (DCMU) at 10-5 M to freshly prepared chloroplasts inhibited the photoreduction of TPN by more than 98 %, and activity was restored to 94 %o f the original value by addition of ascorbate and.DPIF. Hydroxylamine at 10-3 Mand ammonium ion at 0.17 M produced similar effects. Qualitatively similar results were obtained with .these three inhibitors for photoreduction of DPN, indigo , carmine, .riboflavin-5 1 -phosphate, vitamin K3, methyl red and tetrazolium blue. Cesium ion and orthophenanthroline produced inhibitory effects similar to those of DCMU, hydroxylamine and ammonium ion which responded analogously to the DPIP-ascorbate couple. The data substantiate the previously proposed idea that ascorbate is photooxidized in the absence of oxygen by the photochemical oxidizing equivalents produced by illuminated chloroplasts, with the dye DPIP· acting as intermediate electron carrier. With intact .chloroplasts 2 the oxidizing equivalents are utilized preferentially for oxidation of water to produce oxygen. Only after the oxygen-evolution .system becomes .inoperativec1;1.n the ascorbate-DPIP couple compete successfully for the oxidizing equivalents. ExPosure of chloroplasts . to . light for 20 minutes _prior to ,adding .a Hill oxidant resulted in a reduced photoreducin,g capacity in the Hill reaction with TPN, indigo .carmine .and tetrazoli:um blue. However, such a treatment .actually increased the photoreducing _ability of the chloroplasts in the presence of DPIP and .ascorbate. Chloroplasts were inactivated toward the Hill reaction .by a pH of 7.7 at 30°. This inactivation was .readily overcome by addition of ascorbate and DPIP, indicating that .the principal effect of this treatment was to inactivate the oxygen-evolution system. Since indigo carmine photoreduction is stabili.z-ed· much more by the presence of sucrose in the reaction mixture than the photoreduction of DPIP it is indicated that there are components in the electron transport system leading from the site of DPIP photoreduction to that of indigo carmine photoreduction which .are sensitiye to distilled water dilution. The photoreduction of TPN, PPN .and indigo carmine was stimulated by addition of cysteine, whereas reduced glutathione was without effect. Cysteine was unable to overcome the inhibitions of DCMU, hydroxylamine and ammonium ion and no stimulation was observed when cysteine was .added to the inhibited systems containing DPIP and ascorbate even though cysteine was capable of stimulating the uninhibited reaction containing the DI"IP-ascorbate couple. It was there3 fore concluded that cysteine acts by stabilizing or reacting with the oxygen-evolving system. Chloride-deficient chloroplasts .were stimulated by added chloride and cyanide in Hill reaction activities. Reaction .mixtures containing sufficient chloride to provide maximal stimulation were further stimulated by added cyanide, versene and Tris.
14

Development of a Hardware-In-the-Loop Simulator for Battery Management Systems

Wang, Lingchang, XI 16 September 2014 (has links)
No description available.
15

Conception, simulation et implantation sur SOPC d'un analyseur d'impédance rapide dédié aux capteurs et transducteurs piézoélectriques / Design, simulation and implantation on SOPC of a fast impedance analyzer dedicated to the sensors and transducers piezoelectric

Hamed, Abdulrahman 24 May 2012 (has links)
Les systèmes piézoélectriques sont utilisés dans un grand nombre d'applications (mesures physiques, contrôle non destructif). Beaucoup d'entre elles nécessitent la mesure rapide de l'impédance électrique du capteur, particulièrement dans le cadre des microsystèmes. C'est pourquoi ce travail est consacré à la conception et au développement d'un analyseur d'impédance sur puce. L'analyseur est programmable en fréquence et en impédance et est implanté sur un système embarqué de type FPGA (field programmable gate array). Nous proposons trois méthodes à l'analyse leur impédance : une mesure ratiométrique, une modélisation paramétrique adaptative du capteur et une méthode originale utilisant l'asservissement de la tension d'excitation par un réseau résistif programmable. L'implantation des algorithmes sur la cible FPGA est réalisée selon une approche de type HIL (Hardware In the Loop) / The piezoelectric systems are used in many applications (physical measurements, non-destructive testing). Many of them require fast measurement of the sensor electrical impedance, particularly in the micro systems domain. Therefore this work is dedicated to the design and the development of an impedance analyzer on chip, programmable in frequency and impedance, and implantable in an embedded system of FPGA (field programmable gate array) type. We propose three methods for impedance analysis: a ratiometric measurement, an adaptive parametric modeling of the sensor, and an original method using the feedback control of the excitation voltage by a programmable resistive network. The implementation of algorithms on FPGA target is performed using HIL (Hardware In the Loop) approach
16

Amostragem do ácaro-do-bronzeado dichopelmus notus keifer (acari, eriophydae) na cultura da erva-mate em Chapecó, Santa Catarina / Sampling of the ácaro-de - bronzed dichopelmus notus keifer (acari, eriophydae) in the culture of the erva-mate in Chapecó, Santa Catarina

Vieira Neto, João 10 April 2006 (has links)
The mate-tea tree it is a forest species that occurs naturally in the tempering regions and subtropical of America of the South. In Brazil it occurs mainly in the states of the Rio Grande do Sul, Paraná and Santa Catarina. Its leaves and branches are used, mainly, as raw material in the preparation of teas. During many years, the exploration of mate-tea if restricted the natives plants, but recently it passed also to be cultivated in monoculture, system that favors the development of pragues. The tan-mite, Dichopelmus notus (Keifer, 1959) (Acari, Eriophydae), specific plague of this culture, that before met in low population levels, currently due to the high infestations, cause the premature leaf fall and death of the tips, with elevated damages to the producers. This mite comes being considered as one of the main pragues of the culture of mate-tea in the Argentine and Brazil. In result of the importance of mate-tea and of the increase of the infestation of this mite, it is necessary to search alternatives and technologies that maximize the profitability of the culture. This work aimed to select a sampling methodology to monitor the levels of infestation of the tan-mite in matetea orchards, destined to explain its habits. The study were carried out in orchard of ten years, in the arrangement of 2,5 X 4,0 m with height of 1,5 m, located in the Chapecó county, Santa Catarina state, Brazil. In three areas of approximately 2,500 m2, distant between itself about 100 m, had been selected 30 plants randomly. Fortnightly, in the period of 27/01/2004 the 10/01/2005, were evaluated infestation of D. notus in 18 mature leaves of ten plants in each area, being six in the upper one-third, six in the medium one-third and six in lower one-third, three in each localization of the crown, external and internal. The evaluations were executed directly in the orchard, using lenses with increase of ten times and 1 cm2 of fixed field. The results had evidenced that: the infestation of the mite occurs of aggregate form; the estimate of the average number of mites for cm2 of leaf, with level of 15% precision, can be carried through in three leaves of 30 plants in sections of hectare, from february to april; the mites concentrate themselves in the external part of the plant in the upper one-third part of canopy as well as at part medium one-third; positive correlation was observed among the population of D. notus and minimum and maximum temperatures, however negative correlations was observed among tan-mite e population and rain precipitation, relative humidity and speed of the wind; the Model of Normal Approach with Correction of Continuity must preferential be used in the elaboration of binomial sequential sampling plans for D. notus. / A erva-mate é uma espécie florestal que ocorre naturalmente nas regiões temperadas e subtropicais da América do Sul. No Brasil ocorre principalmente nos estados do Rio Grande do Sul, Paraná e Santa Catarina. Suas folhas e outras partes do ramo são utilizadas, principalmente, como matéria-prima no preparo de chás. Durante muitos anos, a exploração da erva-mate se restringiu a ervais nativos, mas recentemente passou a ser cultivada também em monocultura, sistema que favorece o desenvolvimento de pragas. O ácaro-do-bronzeado, Dichopelmus notus (Keifer, 1959) (Acari, Eriophydae), praga específica dessa cultura, que antes encontrava-se em baixos níveis populacionais, atualmente devido às altas infestações, provoca a queda prematura de folhas e morte dos ponteiros, com elevados prejuízos aos produtores. Esse ácaro vem sendo considerado como uma das principais pragas da cultura da erva-mate tanto na Argentina como no Brasil. Em decorrência da importância da erva-mate e do aumento da infestação desse acarino, é necessário buscar alternativas e tecnologias que maximizem a rentabilidade da cultura. Este trabalho teve como objetivo selecionar uma metodologia de amostragem para monitorar os níveis de infestação do ácaro-do-bronzeado em lavouras de erva-mate, destinada a esclarecer aspectos de sua bioecologia. O estudo foi conduzido em erval de dez anos, no espaçamento de 2,5 X 4,0 m com altura de 1,5 m, localizado no município de Chapecó, SC. Em três áreas de aproximadamente 2.500 m2 , distantes entre si cerca de 100 m, foram selecionadas 30 plantas ao acaso. Quinzenalmente, no período de 27/01/2004 a 10/01/2005, avaliou-se a infestação de D. notus em 18 folhas maduras de dez plantas em cada área, sendo seis no terço superior, seis no terço médio e seis no terço inferior, em cada terço, três na parte externa da copa e três na interna. As avaliações foram executadas diretamente nos ervais, utilizando lentes com aumento de dez vezes e 1 cm2 de campo fixo. Os resultados evidenciaram que: a infestação do ácaro ocorre de forma agregada; a estimativa do número médio de ácaros por cm2 de folha, com nível de precisão de 15%, pode ser realizada em três folhas de 30 plantas em talhões de um hectare, nos meses de fevereiro a abril; os ácaros concentram-se na parte externa da copa da planta nos terços superior e médio; há correlação positiva entre a população de D. notus e temperaturas mínimas e máximas e correlações negativas com a precipitação pluviométrica, umidade relativa e velocidade do vento; o Modelo de Aproximação Normal com Correção de Continuidade deve ser preferencialmente utilizado na elaboração de planos de amostragem seqüencial binomial para D. notus.
17

Contribution à la commande et à l'observation des Systèmes Mécatroniques / Contribution to the control and the observation of Mechatronic Systems

Edjekouane, Essaid 04 July 2016 (has links)
L'ensemble des travaux présentés ont été effectués dans le cadre d'une thèse CIFRE entre le laboratoire Quartz EA 7393 et l'entreprise SDI. Ce travail a pour but d'apporter des solutions aux problématiques rencontrées par les ingénieurs de SDI dans le métier des essais. Le cercle de l'étude relève du domaine de la mécatronique. Ainsi, nous nous sommes attachés dans un premier temps à l'étude de l'asservissement des vérins pneumatiques. En effet, lorsqu'il s'agit de commander ce type de vérins sous des perturbations inconnues les algorithmes de commande de SDI ne permettent pas dans ces cas là de satisfaire le cahier des charges. Pour améliorer leurs performances, une commande non linéaire robuste basée sur la théorie de l'homogénéité a été développée au laboratoire Quartz et tester en temps réel à l'aide de Matlab/Simulink et d'une carte dSPACE $1103$. Par la suite, cette commande a été intégrée avec succès sur le logiciel propriétaire X'SPARe. Cette solution a donné toute satisfaction par rapport aux performances et à la fiabilité de la production industrielle.Dans un deuxième temps, un système ABS de type Bosch $5.0$ a été testé en temps réel sur un banc d'essai HIL (Hardware-in-the-loop). Pour cette raison, un modèle du véhicule a été développé sous Matlab/Simulink avec un algorithme de sélection de profils de routes qui a été intégré avec succès dans le logiciel X'SPARe. Les essais effectués en temps réel ont permis de tester l'ABS sous différents profils de routes et de valider le modèle du véhicule sur la base des distances d'arrêt obtenues en se référant aux normes du standard international SAE. / The work presented in this thesis was conducted in the context of a CIFRE contract between Quartz (EA 7393) laboratory and SDI company. This work aimed to provide best solutions to the problems encountered by SDI engineers in craft testing in the field of mechatronics. We focused first on the feedback control synthesis for a pneumatic cylinder. In fact, the control algorithms already implemented within SDI pneumatic systems do not meet the desired specifications. Therefore, a robust non-linear control based on the homogeneity theory was developed at Quartz laboratory and tested in real time using Matlab/Simulink and the dSPACE 1103 card. This control algorithm was successfully integrated within the SDI software X'SPARe. This solution gave entire satisfaction regarding performance and reliability in an industrial context.Concerning the second contribution, a Bosch $5.0$ ABS type system is to be tested in real time on a HIL test bench. For this reason, a vehicle model involving an impulsive observer was developed in Matlab/Simulink including the possibility to specify/estimate the road profiles. This model was also successfully integrated under the software X'SPARe. The tests conducted in real time allowed to characterize the ABS system under various road profiles and to validate the vehicle model as well as the observer based on the stopping distances obtained by referring to the SAE organization standards.
18

Outils de prototypage pour la conception de systèmes complexes / Prototyping tools for the design of complex systems

Louali, Rabah 29 September 2016 (has links)
Cette thèse s’inscrit dans le contexte des systèmes embarqués qui sont qualifiés de complexes car leur développement nécessite une expertise pluridisciplinaire. Une stratégie de développement s'avère incontournable pour concevoir ces systèmes. Cette complexité est encore plus sévère dans le domaine du développement des systèmes embarqués pour UAV.Nous proposons une approche de développement orientés systèmes embarqués basés COTS. Cette démarche combine plusieurs méthodes issues du génie logiciel classique que nous avons adapté aux systèmes embarqués. Nous avons appliqué cette approche pour développer un système de capteurs embarqués pour un micro-UAV à voilures fixes.Le système embarqué développé a été déployé sur un robot classique, une bicyclette et un modèle réduit d'avion. L'objectif est de valider la consistance des données capteurs, compte tenu de la disparité des dynamiques entres ces systèmes. Ces expériences ont permis de mettre en évidence des similitudes théoriques entre ces 3 dynamiques. L'objectif est de pouvoir valider des systèmes embarqués pour UAV sur des plateformes à moindre coût et à moindre complexité, tout en garantissant la consistance des données capteurs et leur interprétation par rapport aux trois plateformes. Nous avons construit, aussi, une plateforme de simulation dont l’objectif est de supporter l’approche de développement proposée. Nous avons utilisé cette plateforme pour concevoir un système de contrôle, guidage et navigation pour un UAV à voilures fixes. Ces applications montrent, ainsi, l’efficacité de l’approche de développement proposée. / This thesis tackles the problem of embedded system design, which are often qualified as complex systems because their development requires multidisciplinary expertise. A development strategy is then essential to design these systems. As an application, we focused on UAV embedded systems, which show very severe development constraints.We propose a development approach oriented COTS-based embedded systems. This approach combines several methods from classic software engineering filed that we have adapted for embedded systems. We applied this approach to develop an embedded sensors system for a micro fixed wings UAVs.The designed embedded system has been deployed on an UAV, a mobile and a bicycle. The aim is to validate the UAV embedded system using a lower cost platforms and with less complexity, while ensuring sensors data consistency and interpretation regarding the dynamic of the three platforms. These experiments highlight the theoretical similarities between those three dynamics. Furthermore, we built a simulation platform that aims to support the proposed development approach. We used this platform to design a control, guidance and navigation system for a fixed wings UAV. These applications show the effectiveness of the proposed development approach.
19

Hardware-in-the-loop simulation and testing of the ADCS of the Beyond Atlas CubeSat

Mahanti, Kritee January 2021 (has links)
Beyond Atlas, a company based in Danderyd, Sweden is working on a Low Earth Orbit (LEO) 3U-CubeSat (Cube Satellite) exploration mission. As part of their maiden mission, they aim to validate the navigation, propulsion, and communication techniques of a CubeSat while it performs orbital maneuvers to collect photographs of space debris. This study briefly introduces the Beyond Atlas mission and its CubeSat design. The thesis work then mainly focuses on the details of the Attitude Determination and Control System (ADCS) peripherals and software onboard the CubeSat. It describes the Attitude Determination peripherals such as the sun sensor, star tracker, magnetometer, and gyroscope that will be onboard the CubeSat, followed by the description of the Attitude Control peripherals, namely, the magnetorquer and the reaction wheel. Subsequently, it discusses the hardware’s configuration and interface techniques with the flight computer that specifically caters to the satellite’s attitude determination and control aspect. Finally, it reports a Hardware-in-the-loop (HIL) testing methodology, and the corresponding results obtained from the unit testing of the peripherals and the operational testing (Detumbling and Pointing) of the ADCS of the Beyond Atlas CubeSat. Based on the testing results, the report concludes that the selected hardware for the Beyond Atlas mission, when integrated, can perform the principal functionalities. / Beyond Atlas baserat i Danderyd, Sverige är ett företag som arbetar med ett rymdutforsknings projekt. Som en del av deras jungfruuppdrag används en 3UCubeSat för att validera navigering, framdrivning och kommunikationsningar medan den utför banmanövrer för relativnavigation och tar bilder av rymdskräp. Denna studie introducerar kort Beyond Atlas uppdraget och dess CubeSat-design. Rapporten fokuserar sedan huvudsakligen på detaljerna i ADCS kringutrustning och programvara ombord på CubeSat. Den beskriver attitydkännande utrustning som solsensorer, startracker, magnetometer och rategyro som finns ombord, följt av beskrivningen av attitydst yrenheter, nämligen magnetorquer och reaktionshjul. Därefter diskuteras hårdvarans konfiguration och gränssnitt med navigationsdatorn som dedikerat utför satellitens attitydbestämning och attitydkontroll ADCS. Slutligen rapporterar studien testmetodik av inledande validerings-tester (Detumbling and Pointing) av ADCS i Beyond Atlas CubeSat. Baserat på testresultaten drar rapporten slutsatsen att den valda hårdvaran för satelliten kan utföra de primära navigationsfunktionerna.
20

Estudo do efeito antinociceptivo e/ou anti-inflamatório das folhas de Spiranthera odoratissima A. St.-Hil. (Manacá). -Possível mecanismo envolvido / Study of analgesic effect and / or anti-inflammatory Leaves Spiranthera odoratissima A. St.-Hil. (Manacá). -Possible mechanism involved

BARBOSA, Daniela Borges Marquez 30 August 2010 (has links)
Made available in DSpace on 2014-07-29T16:11:48Z (GMT). No. of bitstreams: 1 Daniela Borges Marquez Barbosa.pdf: 1035772 bytes, checksum: c1908f359735473ebf92878acb93eee7 (MD5) Previous issue date: 2010-08-30 / Spiranthera odoratissima A. St.-Hil. is popularly known as Manacá and it is a native plant of the Brazilian Savanna Cerrado, and it can be found in the states of Mato Grosso, Goiás, Minas Gerais and Bahia. In the folk medicine this plant is used as an appetite stimulant and to treat rheumatism, abdominal pain, headache, muscle pain, stomach and liver dysfunction, kidney infections and urinary retention. The hydromethanolic fraction was obtained from the ethanolic extract of Spiranthera odoratissima leaves. According to phytochemical screening this fraction contains anthraquinones, tannins, flavonoids and coumarins. This fraction showed antinociceptive activity in the acetic acid-induced writhing method and the involvement of central antinociceptive mechanisms was discarded with the hot plate test, since the reduction in the latency to pain was not observed. The major subfraction isolated from the hydromethanolic fraction (sub-Fr10-28) showed antiinflammatory activity in different methodologies. Both hydromethanolic fraction and sub-Fr10-28 contain tannins able to inhibit the activity of phospholipase A2 enzyme, and subsequently inhibiting the production of arachidonic acid and preventing the production of eicosanoids such as prostaglandins, thromboxanes and leukotrienes by lipoxygenase and cyclooxygenase enzymes participation. These eicosanoids are important mediators for the maintenance of inflammatory process. Concluding, the analgesic effect of this plant may be due to an anti-inflammatory action, and this antiinflammatory action could be the result from the blockage of the phospholipase A2 enzyme. / Spiranthera odoratissima, conhecida popularmente como Manacá nativa em cerrado ralo, é encontrada nos estados de Mato Grosso e Goiás, Minas Gerais e no estado da Bahia. Na medicina popular essa planta é utilizada para o tratamento de reumatismo, dores abdominais, dores de cabeça, dores musculares, dores de estômago, infecções renais e hepáticas, retenção urinária, e como depurativo e estimulante do apetite. Do extrato etanólico das folhas da Spiranthera odoratissima foi obtida a fração hidrometanólica contendo: antraquinonas, taninos, flavonóides e cumarinas. Essa fração mostrou atividade antinociceptiva pelo método de contorções abdominais induzidas por ácido acético em camundongos e foi descartado o envolvimento de mecanismos antinociceptivos centrais pelo teste da placa quente, onde observou-se a não redução da latência à dor. Foi isolada uma sub-fração majoritária nomeada sub-Fr10-28 que apresentou atividade antiinflamatória nas diferentes metodologias utilizadas. A fração hidrometanólica e sua sub-fração majoritária contêm taninos capazes de inibir a atividade da enzima Fosfolipase A2, inibindo a hidrólise do fosfolipídeo de membrana em ácido araquidônico e impedindo assim, que as enzimas lipoxigenase e ciclooxigenase produzam eicosanóides como prostaglandinas, tromboxanos e leucotrienos, importantes mediadores para a manutenção do processo inflamatório. O efeito analgésico desta planta pode ser devido a uma ação anti-inflamatória e esta pode estar relacionado ao bloqueio da enzima Fosfolipase A2 levando desta forma a uma redução na produção de mediadores inflamatórios.

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