Government legislation on particulate matter (PM) and oxides of nitrogen (NOX) emissions have become increasingly stringent over the past decades. Future projections have led to internal combustion (IC)engine developers exploring advanced combustion technologies which may replace or supplement current state of the art systems. Advanced combustion technologies such as Low Temperature Combustion (LTC) cover a broad series of mechanisms that seek to attain in-cylinder Equivalence ratio (f) - Temperature (T) combinations during combustion which lead to acceptable emissions of exhaust PM and NOX. These are generally achieved by a combination of EGR dilution and extended ignition delays for mixture preparation. Another common feature of LTC is the poor combustion efficiency due to severe requirements placed on mixture quality as lower temperatures and oxygen concentrations reduce local ignitability limits. Therefore, a significant amount of work on LTC is centred around understanding the spatial and temporal development of inadequately prepared mixtures during LTC. The investigations presented in this thesis are expected to contribute to this body of work as they are predicated on the hypothesis that current mixture preparation methods are insufficiently adapted to conditions present in LTC combustion modes.

In this thesis, the multi-carrier (MC) code division multiple access (CDMA) system in Rayleigh fading channel is considered. The system performance will be degraded due to multiple access interference (MAI) or background noise. It is know that linearly constrained inverse QR-decomposition (LC-IQRD) recursive least-square algorithm can overcome the problems. The main concern of this thesis is to implement the circuit of LC-IQRD algorithm. FPGA components and sets up a high efficient programmable hardware module. In this thesis, we implemented the circuit of LC-IQRD algorithm via a chip of Field Programmable Gate Array (FPGA) with Verilog HDL. The conventional IQRD circuit design employs systolic array architecture. The advantages of systolic array architecture include modularity and hardware simplicity. These properties are extremely desirable for VLSI implementation. In fact, we expect to reduce the execution time of the conventional IQRD algorithm circuit design. Therefore, in this thesis a modified IQRD circuit design is proposed to improve the effect of circuit implementation. It also has advantage of modularity and reduces the execution time. In order to degrade complexity of LC-IQRD algorithm circuit design, the area and speed of circuit are the consideration in this thesis. The data source is produced by Matlab software. We verify the performance of the system in terms of BER (bit error rate) and SINR (signal to interference and noise ratio).Finally, LC-IQRD algorithm circuit is realized in the Altera EP20k1500EFC-33 chip and on the Quartus II of Altera. The algorithm circuit uses 51536 logic elements (LE) for 30 bits fixed point design.

This thesis mainly focuses on the integration of Space-Time Block Coding (STBC) and Complementary Code based CDMA system. Our proposed integration systems have not only the merit of complementary code but also the extra advantage of diversity gain from STBC. Especially, when the different frequency channel gain has strong correlation, the complementary code will cancel most of interference. We also present a lot of improved structures for our proposed systems. We utilize special filters in receiver such as Zero-Forcing filter and Turbo Filter to assist complementary code in canceling interference.

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Mechatronische Produktionsmaschinen werden nicht mehr nur über ihren Leistungsumfang bewertet, sondern auch über die mitgebrachten Tools für Engineeringaufgaben. Wie erste Ansätze zeigen, erweitert die Integration von TCP/IP in die Steuerungsebene die Möglichkeiten zur Unterstützung des Anwenders nicht nur im Fertigungsprozess, sondern nahezu über den gesamten Lebenszyklus. Die Dissertation beschreibt einen E-Service zur Inbetriebnahme von Lagereglern an Bewegungssteuerungen. Im Rahmen der prototypischen Realisierung erfolgt der Aufbau eines Dienstleistungsportals in einem Computernetz. Es übernimmt eine zentrale Rolle in der Kommunikationsstruktur. Aufgaben rund um die Dienstverwaltung, Dienstausführung und Dienstkommunikation von verteilten Programmen bilden hier die Schwerpunkte. Die Einordnung der realisierten und favorisierten Reglerinbetriebnahme erfolgt in die Gruppe der Offline-Verfahren. Auf dem gewählten Zielsystem, der Bewegungssteuerung SIMOTION von Siemens, läuft dabei der Echtzeitteil ab. Die Offline-Komponente mit den Identifikations- und Reglerberechnungsprogrammen wird im Anwender-Browser ausgeführt. Das System bildet zusammen einen internetbasierten, automatischen Service.

Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal

Les densités d'intégration actuelles des circuits intégrés permettent de disposer de SoC (systèmes sur puce) de plus en plus complexes, intégrant de plus en plus de standards. Par conséquent, le problème des interconnexions entre tous les blocs IP (Intellectual Property) constituant le SoC devient un point critique que les structures de communications actuelles ne parviennent plus à solutionner.<br />Ces problèmes sont notamment liés aux besoins de plus en plus forts en mobilité et en débit dans les architectures de communication actuelles et futures. Ainsi, les solutions à base de NoC (Network on Chip) offrent de bonnes perspectives en terme de bande passante et de flexibilité pour pallier notamment aux limites actuelles des topologies bus. Les travaux de thèse présentés ici portent sur la méthodologie de modélisation et d'exploration d'architectures de réseaux sur puce appliquée aux télécommunications.<br />Le contexte radio-télécommunications étudié est celui proposé dans le cadre du projet Européen 4MORE pour lequel nous avons contribué. Une des contraintes de ce projet était d'intégrer dans un SoC la technique MC-CDMA (Multiple Carrier Code Division Multiple Access) combinant la technique MIMO en utilisant un média de communication innovant.<br />Ainsi, nous avons contribué à cette intégration en proposant une méthodologie de conception permettant d'aider le concepteur dans le choix des différents paramètres caractérisant le NoC pour satisfaire les contraintes temps réel de l'application spécifiées dans le cahier des charges.<br />Ces travaux de thèse ont porté sur la modélisation et l'interconnexion des composants IP constituant la chaîne algorithmique du projet 4MORE afin de les intégrer dans un modèle SystemC du NoC. Par ailleurs, les choix de dimensionnement du réseau et des contraintes de placement des blocs IP sur celui-ci ont un impact important sur les performances globales de l'application. Nous avons mis en place un outil AAA (Adéquation Algorithme Architecture) permettant de réaliser l'adéquation des contraintes de l'application sur l'architecture en minimisant les chemins de communication tout en veillant à ne pas violer les bandes passantes théoriques des liens de communication entre routeurs.<br />Le flot de conception mis en œuvre permet au concepteur de générer le modèle SystemC du NoC et permettra à cours terme de générer le code VHDL associé du modèle SystemC simulé afin d'accélérer les phases de simulation et de donner la possibilité de valider logiciellement et matériellement (cible FPGA) l'architecture avec son application.

Research in selenium isotopes has been gaining interest as new contaminated sites are identified around the world. Selenium is an emerging contaminant, as it is increasingly being released through anthropogenic activities. It is an element with a very narrow range between nutrient requirement and toxic concentrations. Increased concentrations in the environment are a cause for concern. Selenium can be made less toxic in a system through reduction. Currently, investigations into fractionation caused by the reduction of Se by Fe and Fe minerals are limited. This thesis describes a batch study conducted using granular iron to treat Se(VI) in CaCO3 saturated water, under anaerobic conditions. The amount of Se(VI) in solution decreased to 14.5% of the initial concentration within three days. No quantifiable Se(IV) was found in solution. Analysis of the solid phase showed Se(IV), ferric selenite, FeSe, and Se(0) on the GI. The mass of Se0 on the GI increased over time. Iron selenide compounds became more prevalent after two days had elapsed. Effective fractionations of 4.3??? for 82/76Se and 3.0??? for 82/78Se were observed for this reaction. These effective fractionations are lower than fractionations observed in other experiments for reduction in solution. This discrepancy may be due to the reduction of Se(IV) occurring after adsorbing onto the solid phase, rather than reduction taking place only in solution.

Multicarrier code division multiple access (MC-CDMA) is a very promising candidate for the multiple access scheme in fourth generation wireless communi- cation systems. During asynchronous transmission, multiple access interference (MAI) is a major challenge for MC-CDMA systems and significantly affects their performance. The main objectives of this thesis are to analyze the MAI in asyn- chronous MC-CDMA, and to develop robust techniques to reduce the MAI effect. Focus is first on the statistical analysis of MAI in asynchronous MC-CDMA. A new statistical model of MAI is developed. In the new model, the derivation of MAI can be applied to different distributions of timing offset, and the MAI power is modelled as a Gamma distributed random variable. By applying the new statistical model of MAI, a new computer simulation model is proposed. This model is based on the modelling of a multiuser system as a single user system followed by an additive noise component representing the MAI, which enables the new simulation model to significantly reduce the computation load during computer simulations. MAI reduction using slow frequency hopping (SFH) technique is the topic of the second part of the thesis. Two subsystems are considered. The first sub- system involves subcarrier frequency hopping as a group, which is referred to as GSFH/MC-CDMA. In the second subsystem, the condition of group hopping is dropped, resulting in a more general system, namely individual subcarrier frequency hopping MC-CDMA (ISFH/MC-CDMA). This research found that with the introduction of SFH, both of GSFH/MC-CDMA and ISFH/MC-CDMA sys- tems generate less MAI power than the basic MC-CDMA system during asyn- chronous transmission. Because of this, both SFH systems are shown to outper- form MC-CDMA in terms of BER. This improvement, however, is at the expense of spectral widening. In the third part of this thesis, base station polarization diversity, as another MAI reduction technique, is introduced to asynchronous MC-CDMA. The com- bined system is referred to as Pol/MC-CDMA. In this part a new optimum com- bining technique namely maximal signal-to-MAI ratio combining (MSMAIRC) is proposed to combine the signals in two base station antennas. With the applica- tion of MSMAIRC and in the absents of additive white Gaussian noise (AWGN), the resulting signal-to-MAI ratio (SMAIR) is not only maximized but also in- dependent of cross polarization discrimination (XPD) and antenna angle. In the case when AWGN is present, the performance of MSMAIRC is still affected by the XPD and antenna angle, but to a much lesser degree than the traditional maximal ratio combining (MRC). Furthermore, this research found that the BER performance for Pol/MC-CDMA can be further improved by changing the angle between the two receiving antennas. Hence the optimum antenna angles for both MSMAIRC and MRC are derived and their effects on the BER performance are compared. With the derived optimum antenna angle, the Pol/MC-CDMA system is able to obtain the lowest BER for a given XPD.