The revolutionary progress that happened recently in the micro-electro mechanicalsystems (MEMS) field and the complementary metal-oxide-semiconductor(CMOS) integrated circuits has made it possible to produce low-cost, low-powerand small size processing circuits. Utilizing wireless communication theory allowsthose circuits to send their data over a network. This wireless sensor network isknown as "Smart Dust". Each wireless sensor node in the network is indicated as "mote". It consistsof several components: sensors, micro-processors, radio transceivers and a powermanagement unit. The power management unit can be divided into several partsincluding battery, power control and regulator. The purpose of the regulator is tosupply a constant reliable voltage to the other parts in the mote as most of thedevices have voltage limits that need to be considered to guarantee producing arobust long-life mote. In this thesis designing a low-power regulator is investigated. The goal of thethesis is to design a regulator that can handle the high-voltage acquired froman energy harvest unit using only 65-nm core transistors. This allows an easierproduction process that results in a low-cost fully-integrated chip. The regulatorarchitecture to be used is a simple linear regulator. The report highlights the theoretical background, the challenges of the analogdesign and presents the results of the simulation that were ran using cadence designsystem software on schematic level.

The nature of the calcium-silicate-hydrate phase in hydrated Portland cement has been the subject of considerable debate for decades. Various nanostructural models have been proposed including those constructed from colloidal-based particulate systems and those formulated on the basis of layered calcium-silicate-hydrates. These are examined in detail in the literature review section of the thesis. Relatively recent composition-based models have been proposed by Taylor and Richardson-Groves. These models contain structural elements comprised of 1.4 nm tobermorite and jennite. Details are also provided in the literature review. There is however a paucity of data on the engineering properties of pure calcium-silicate-hydrate phases and virtually none on the mechanical performance of 1.4 nm tobermorite and jennite. The global objective of this thesis was to examine the compatibility of the composition-based models with the engineering behaviour of the pure tobermorite and jennite phases. Pure phases of a variety of layered calcium-silicate-hydrates were synthesized and novel techniques developed to determine their engineering characteristics in a variety of test environments. The silicate phases investigated included high temperature silicates e.g. gyrolite as these layered structures are known to be cross-linked. Investigation of the role of ‘structural’ water in layered silicates was also a part of these studies. The thesis is based on a series of twelve refereed journal papers by the candidate (eight are published or accepted and four have been submitted for publication). The research is reported in four parts with each part comprised of three papers. Each part provides insight into the nanostructure of C-S-H in hydrated cement. The arguments developed evolve from an assessment of various factors including aging and the state of water in the layered silicates. The first part of the thesis focuses on the development and application of dynamic mechanical thermo-analysis methods that are sensitive to phase changes and are useful for assessing the compatibility of engineering behaviour with model composition based on 1.4 nm tobermorite and jennite. The second part represents a study of volume stability and mechanical property-porosity relationships for the pure silicate phases that are germane to these studies. The third part focuses on prolonged aging and role of structural water in cement paste hydrated for 45 years. The fourth and final part attempts to address the role of layer structure e.g. cross-linking of silicate sheets on engineering behaviour. The non-uniqueness of modulus of elasticity with respect to equilibrium moisture content is demonstrated. Structurally related irreversible effects that are dependent on drying history are rationalized. A summary chapter is provided wherein the evidence for a composition-based model with tobermorite and jennite structural units is rationalized in terms of the experimental evidence provided in this study and suggestions for future research are discussed.

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Partially coherent interaction of the feedback light with the field in the laser cavity is affirmed with the fiber Bragg grating (FBG) stabilized 980-nm pump lasers, on the contrast of normally accepted totally incoherent state of operation in the “coherence collapse” regime. Coherence parameter y was defined in this paper to identify the fraction of feedback light working coherently. It is shown that y can be determined by fitting the measured power-difference versus pumping-rate curve to the simulation results. Experiments confirm that coherence parameter y decreases while the distance between the FBG and the laser facet increases, and vice versa. While, if the device is kept operating in the “coherence-collapse” regime, y would not change with the amount of feedback. This work will be help to improve the performance of the high power FBG stabilized 980-nm pump laser. / Thesis / Master of Applied Science (MASc)

La diminution de la taille des transistors actuellement utilisés en microélectronique ainsi que l’augmentation de leurs performances demeure encore au centre de toutes les attentions. Cette thèse propose d’étudier et de fabriquer des transistors à base de nanofils empilés. Cette architecture avec des grilles enrobantes est l’ultime solution pour concentrer toujours plus de courant électrique dans un encombrement minimal. Les simulations ont par ailleurs révélé le potentiel des nanofeuillets de silicium qui permettent à la fois d’optimiser l’espace occupé tout en proposant des performances supérieures aux dispositifs actuels. L’importance de l’ajout de certaines étapes de fabrication a également été soulignée. En ce sens, deux séries d’étapes de fabrication ont été proposées : la première option vise à minimiser le nombre de variations par rapport à ce qui est aujourd’hui en production tandis que la deuxième alternative offre potentiellement de meilleures performances au prix de développements plus importants. Les transistors ainsi fabriqués proposent des performances prometteuses supérieures à ce qui a pu être fabriqué dans le passé notamment grâce à l’introduction de contraintes mécaniques importantes favorables au transport du courant électrique. / The future of the transistors currently used in Microelectronics is still uncertain: shrinking these devices while increasing their performances always remains a challenge. In this thesis, stacked nanowire transistors are studied, fabricated and optimized. This architecture embeds gate all around which is the ultimate solution for concentrating always more current within a smaller device. Simulations have shown that silicon nanosheets provide an optimal utilization of the space with providing increased performances over the other technologies. Crucial process steps have also been identified. Subsequently, two process flows have been suggested for the fabrication of SNWFETs. The first approach consists in minimizing the number of variations from processes already in mass production. The second alternative has potentially better performances but its development is more challenging. Finally, the fabricated transistors have shown improved performances over state-of-the-art especially due to mechanical stress induced for improving electric transport.

Die vorliegende Studie untersucht mittels eines Diodenlaser (808 nm) zur axillären Epilation, inwieweit eine Reduktion der applizierten Einzelenergie mit angepasster Pulsdauer und repetitiver Pulszahl (Low-Fluence) eine Verträglichkeitssteigerung, bei gleichzeitigem Erhalt der Epilationseffektivität, wie er von traditionelle High-Fluence Applikationen bekannt ist, bewirken kann. Es wurden die Axillae von 21 Patienten des Hauttyps eins bis drei nach zwei unterschiedlichen Protokollen im vierwöchigen Intervall behandelt. Auf der linken Seite erfolgte die Therapie sechsmalig mittels Low-Fluence, wohingegen auf der rechten Seite eine Kombination von dreimalig Low-Fluence- und dreimalig High-Fluence-Modus appliziert wurde. Es konnte hinsichtlich der Effektivität kein statistisch signifikanter Unterschied zwischen beiden Behandlungsmethoden nachgewiesen werden. Die Reduktion zeigte sich konstant und lag am Ende der 24-monatigen Gesamtstudiendauer im Mittel bei 45%. Die Ergebnisse stellen sich damit schlechter dar, als bei konventionellen Studien im High-Fluence-Bereich oder anderen Low-Fluence-Konzepten. Als Ursache ist am ehesten eine unzureichende Einzelimpulsdauer und eine zu gering gewählte Pulswiederholungsanzahl zu sehen. Andererseits ergab sich eine deutliche Verträglichkeitssteigerung, vor allem hinsichtlich des Schmerzempfindens und im Auftreten von Pigmentierungsstörungen zu Gunsten der Low-Fluence-Therapie.

The overall objective of this study is to compile the ethnohistory and contemporary perspectives of selected historically connected Hispanic communities that were affected by the OST. The project can be divided into two parts: 1) a brief history of each community under study and its historic relationship to the OST, and 2) a description of contemporary community views of the trail. Of special interest will be any contemporary knowledge related to the role played by the trail (and/or events related to the trail’s history and use) that affected the history and perspective of each community. Also of interest will be any places or resources along the trail that have significant cultural meaning to the subject communities. The selected communities targeted by this project are intended to sample the range of ethnic, geographic, and historically-connected populations along the trail routes. These include Hispanic communities associated with the development of the trail, communities founded by emigrant populations known to have used sections of the trail as migration routes in the 19th century, communities that were established to support trail trade, and communities that were founded along the trail after its period of historic use. The following communities participated in this study: Abiquiú, New Mexico, Gallina, New Mexico, San Luis, Colorado, Agua Mansa, California, and San Gabriel, California.

Neste trabalho, foi desenvolvido um laser pulsado utilizando um chaveador-Q passivo em uma cavidade com a tecnologia de controle de modo por duplo-passo. Utilizando um cristal de Nd:LiYF4 com 0,8 mol% de dopagem, foi possível gerar um pulso com duração de 5,5 ns (FWHM), com 1,2 mJ de energia e potência pico de 220 kW para utilização na técnica Cavity Ring-Down Spectroscopy (CRDS). A técnica (CRDS), que pode ser traduzida por espectroscopia de cavidade ressonante, é utilizada para medida de espectros de absorção de gases, líquidos e sólidos. Com a técnica CRDS é possível medir perdas com altíssimo grau de precisão, ressaltando sua sensibilidade que é confirmada pela utilização de espelhos com alta refletividade. Foram avaliadas, com essa técnica, as perdas por reflexão e espalhamento de materiais transparentes. Após a calibração da cavidade ressonante, foi possível medir as perdas nas amostras com resolução de até 0,045%, sendo o valor máximo alcançado de 1,73%. Essa calibração foi possível, pois obteve se um tempo de decaimento de aproximadamente 20 μs com a cavidade desobstruída. Também foi conseguido um método de determinação do índice de refração dos materiais transparentes com precisão de cinco casas decimais. / In this work, a pulsed and Q-switched laser resonator was developed using the double-beam mode-controlling technique. A Nd:LiYF4 crystal with 0,8mol% of doping concentration was used to generate a giant pulse with duration of 5,5 ns (FWHM), 1,2 mJ of energy and 220 kW peak power for the Cavity Ring-Down Spectroscopy (CRDS) technique. The CRDS technique is used to measure absorption spectra for gases, liquids and solids. With the CRDS technique it is possible to measure losses with high degree of accuracy, underscoring the sensitivity that is confirmed by the use of mirrors with high reflectivity. With this technique, the losses by reflection and scattering of transparent materials were evaluated. By calibrating the resonant cavity, it was possible to measure the losses in the samples with resolution of 0,045%, the maximum being reached by 1,73%. The calibration was possible because there was obtained to measure a decay time of approximately 20 μs with the empty cavity. Besides was obtained a method for determining the refractive index of transparent materials with accuracy of five decimals.