The purpose intended by the author in this work is an investigation of the adequacy of the first-order theory of junction transistor action to predict within an acceptable degree of accuracy the behaviour with operating conditions of the various parameters of the junction transistor equivalent circuit. A large amount of work has already been done in this direction, but the object of the majority of the experimenters was to arrive at a suitable set of design equations. [...]

In this work, the design, simulation and optimization of a Mach-Zehnder 3-wavelengthoptical demultiplexer (MZ-3WDM) have been performed using a combination of theeffective index method (EIM) and the 2D finite difference vectorial beam propagationmethod (FD-VBPM). Furthermore, the theoretical design and performance predictions ofthe demultiplexer are verified experimentally through device fabrication andmeasurements. The combination of the effective index method based on the Rung-Kutta method and afinite difference vector beam propagation method (FD-VBPM) provide for acomputational design tool that yields useful results. The average extinction ratios of thedemultiplexer, which were achieved theoretically for the 980nm, 1310nm and 1550nmwavelengths are 34db, 32db and 26db respectively. [...] / Dans ce travail, la conception, la simulation et l'optimisation d'un démultiplexeuroptique de 3-longueurs d'onde de Mach-Zehnder (MZ-3WDM) ont été exécutées enutilisant une combinaison de la méthode pertinente d'incrément (EIM) et de la méthodevectoriel de propagation de faisceau de la 2D différence finie (FD-VBPM). En outre, laconception et les prévisions théoriques d'exécution du démultiplexeur sont vérifiéesexpérimentalement par la fabrication et les mesures de dispositif.La combinaison de la méthode pertinente d'incrément basée sur la méthode de RungKuttaet une méthode finie de propagation de faisceau de vecteur de différence (FDVBPM)prévoient un outil de conception de calcul qui donne des résultats utiles. Les tauxmoyens d'extinction du démultiplexeur, qui ont été réalisés théoriquement pour deslongueurs d'onde de 980nm, 1310nm et de 1550nm sont respectivement de 34db, 32db et26db.[...]

Code Division Multiplexing Access (CDMA) transmission technology is used III differentcommercial and military communication systems and, due to the widespread popularity of the 3Gwireless cellphones, CDMA is projected to be used by over 720 million people by 2013 [24], [99].This dissertation work has been motivated by a widely accepted conjecture [27], [92], [135], thatthe (sum) capacity of CDMA transmission with single-user demodulation and single-user decodingat the receiver is limited to about 0.72 bits per channel use (or CDMA chip). This thesis presents aconstructive counter-example to this conjecture and provides design of coding schemes withpractical implementation complexity that can exceed this conjectured capacity limit by more than 5times. The data rate increases, resulting from the capacity analysis and code design in this thesis,can potentially benefit CDMA-based high-speed data communication services in wireless andoptical CDMA networks, e.g., video on demand, high-speed Internet access, security surveillance. / Le multiplexage par division de codes (CD MA) est utilisé dans différents systèmes decommunications commerciaux et militaires, et grâce à la popularité des téléphones cellulaires 3G,il est prévu que CDMA sera utilisé par plus de 720 millions de personnes d'ici 2013 [24], [99].Cette thèse est motivée par une conjecture largement acceptée [27], [92], [135], stipulant que lacapacité théorique des réseaux CD MA utilisant la démodulation et le décodage uni-usager aurécepteur, est limitée à 0.72 bits par accès de réseau (ou chip CDMA). Cette thèse fournie uncontre-exemple constructif à cette conjecture et présente le design de codes concaténés àcomplexité pratique permettant d'excéder plus de 5 fois la capacité supposée. Ces gains encapacité peuvent être bénéfiques aux services à haute vitesse des réseaux optiques et sans filsCDMA, tels que la vidéo sur demande, l'Internet haute vitesse sans fil, les vidéos de surveillance.

The Heat Pump, as a device to provide low grade heat for conditioning purposes, is generally considered to have been originated by Lord Kelvin and its description was contained in papers presented by him in 1852 (75). The original papers described a system capable of transferring heat from a cold temperature to a higher one. Since air was to be the refrigerant, large volumes were required and his cylinder volume was to be 15.63 cubic feet. Power to drive the unit was to be provided by a steam engine and thus was of little practical use.

Measurements of input impedance of cylindrical antennas have been made with a variation of antenna length, diameter and centre spacing. The results are shown in a series of graphs. The variation of resistance and reactance is shown to be in the same direction as contained in the literature.

Canada ranks among the leading countries of the world in the production and exportation of aluminium. In addition, Canadian enterprises operate aluminium plants in several parts of the world. It is rather surprising, therefore, to find relatively little research in Canadian universities dealing with problems in aluminium production. [...]

Specimens of Lake Shore Tuff and Porphyry, Nundydroog Amphibolite, Kerr Addison Green Carbonate Breccia, and McIntyre Carbonated Lava have been ruptured under compression, tension, torsion and direct shear. The results were graphically plotted according to Mohr's strength theory, and the constructed angles of failure compared with the experimental measured angles. According to Mohr, the strength of the rock is a function of sliding friction, but the graphical and experimental results indicate rather that sliding friction and interlocking govern rock failure. [...]

A study was made on the noise generated by a centrifugal ventilating fan and results of the variation of noise with horsepower, speed, air velocity and pressure are given. The results indicate that no one parameter can be used to predict the noise level accurately; and, in agreement with other observers, it is shown that the octave-band distribution is not the same over the complete range of the fan performance curve. [...]

The work described in this thesis comprises the first in a series of projects dealing with servomechanisms at the Department of Electrical Engineering of McGill University. The particular problem investigated was the control of a servomechanism with one nonlinearity, the saturation of the driving element. As a result of the work a twofold purpose was fulfilled. An insight was gained into the problem of utilizing nonlinear control to optimise the transient response, and test equipment and procedures were developed to facilitate complete testing of all aspects of servomechanisms.

The variation in the magnetic properties of Manganese Zinc ferrite produced by changes in the manufacturing process was investigated experimentally. The initial permeability and core loss may be controlled over a wide range by the sintering process. Also, the permeability, core loss, temperature coefficient of permeability and Curie point are strongly dependent on the chemical composition of the material. [...]