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<p> The high-throughput micro-adhesion tester (HMAT) was constructed to test the adhesive strength of polymers. The design criteria included the ability to rapidly test many different samples in a serial format, and a probe design that would compliment this objective by being easy to place and pull from the samples and easy to mass produce. The HMAT was able to perform 48 adhesion tests at about 30s per test for a total of 24 min. The final probes were made from a capillary tube with a small metal cap on the top for ease of lifting. They are easy to make and easy to place and pull from the custom probe box. The probe box was designed to hold the probes upright while the polymer is drying and during the test while not interfering with the test itself. Tests on PDMS show reasonable repeatability with the standard deviation being about 20% of the mean value. Since the HMAT is meant to be used for primary screening, the accuracy of the measurements is not as critical as it would be for later tests. </p> / Thesis / Master of Applied Science (MASc)

This thesis is missing page vi, the page is not present in the other copies of this thesis. -Digitization Centre / This thesis deals with the design and implementation of a micro-computer controlled cutting table used to prepare large scale patterns for Surface Acoustic Wave (SAW) devices. This automated cutting table simplifies the creation of many SAW patterns and makes previously unattainable patterns possible. The design is extremely versatile and can cut as well as straight lines in any direction in two dimensions. A commercially available, 44 inch square, cutting table was automated by mounting stepping motors on each of the two axis. The motion of the motors is controlled by an SDK-85 micro-computer and several peripherals. A full description of the hardware, software and a successful experimental test is included. / Thesis / Master of Engineering (ME)

En esta tesis se estudia el acondicionamiento de la tensión de salida de un sistema de micro cogeneración basado en celdas de combustible. Se emplea un convertidor de tensión cc-cc, que permite acondicionar la tensión de salida del sistema de batería de celdas de combustible modelo Nexa 1200 que posee la Facultad Regional Bahía Blanca de la UTN. El convertidor es de tipo elevador, pero a la entrada, el clásico filtro L, ha sido reemplazado por un filtro LCL, de este modo se espera que la topología presente un valor de rizado prefijado, con componentes de menor volumen. La estrategia de control elegida se basa en la técnica de control por modo deslizante. Además, se utilizan observadores de estados para evitar medir todas las variables involucradas y para estimar la carga variable. Mediante simulaciones y procedimientos experimentales se verifica el correcto desempeño del convertidor. / In this thesis, the conditioning of the output voltage of a micro cogeneration system based on fuel cells is studied. A dc-dc voltage converter is used, which allows conditioning the output voltage of the Nexa 1200 model fuel cell battery system owned by the UTN - Facultad Regional Bahía Blanca. The converter is a step-up converter, but at the input, the classic L filter has been replaced by an LCL filter, in this way it is expected that the topology will present a predetermined ripple value, with components of lower volume. The chosen controlstrategy is based on the sliding mode control technique. In addition, virtual sensors are used to avoid measuring all the variables involved and to estimate the variable load. Through simulations and experimental procedures, the correct performance of the converter is verified.

Existing microstructure parameters of computed tomography (CT) are able to compute architectural properties of the bone from ex-situ and ex-vivo scans while they are highly affected by the issues of noise and low resolution when applied to clinical in-vivo imaging. A set of improvements of the standard workflow for the quantitative computation of micro-structure from clinical in-vivo scans is proposed in this thesis. Robust methods are proposed (1) for the calibration of density values, (2) the binarization into bone and marrow phase, (3) fuzzy skeletonization and (4) the calibration of the CT volumes in particular for the computation of micro-structural parameters. Furthermore, novel algorithms for the computation of rod-volume fraction with 3D rose diagrams and fractal approaches are proposed and the application of local texture operators to diffusion tensor imaging is proposed. Finally an existing computer program for the application in radiology departments, Structural Insight, was improved and largely extended. In particular the methods of the microstructural calibration, the fractal and the texture operators showed significant improvements of accuracy and precision for the prediction of fracture risk and the quantitative assessment of the progress of Alzheimer's disease, in comparison to existing state-of-the art methods. The methods were tested on artificial and in-vitro data and as well on real-world computed tomography and magnetic resonance imaging (MRI) studies. The proposed novel methods improve the computation of bone characteristics from in-vivo CT and MRI in particular if the methods are combined with each other. In consequence, this allows to assess more information from existing data or to conduct studies with less ray exposure and regarding the MRI method in shorter time than nowadays required.

It has always been the desire to get away from the use of hydrogen sulphide (H2S) in the laboratory. In the macro system Brockman (16) developed a method which dispensed with its use. In the June issue of Journal of Chemical Education for 1934 there appeared a system developed by Gerstenzang (17) which dispensed with the use of HaS in micro analysis. With the idea that the system might prove useful here in the University, I undertook a semi-quantitative investigation of it, under the direction of Professor W.0. Walker, to determine the sensitivity of the tests. Solutions of the cations were made up in 500 c.c. bottles so that each c.c. contained 20 mg. of the cation. Smaller dropping bottles were provided so that 1 mg. quantities were easily available. Test reagents were made up according to Treadwell-Hall (19) as specified in the instructions. In all procedures the instructions were followed closely in the first attempts. If difficulties were found in procedure, quantities were varied in an attempt to clear up or overcome the difficulty. / Thesis / Master of Arts (MA)

Gas Chromatography (GC) is one of the most important and widely used tools in analytical chemistry. However, they are bulky, have a longer measurement cycle, and consume a high amount of power. Micro-Gas Chromatography (µGC) is portable and energy-efficient, which allows onsite, real-time biological, forensic, and environmental analyses. This thesis presents a ready-to-deploy implementation of microfabricated gas chromatography (µGC) system capable of separating complex samples. We describe robust, modular, and scalable hardware and software architecture based on Real-Time Operating System (RTOS) and Python Graphical User Interface (GUI) integrated with various microfabricated devices to realize a fully functional µGC system. A sample heater for headspace injection, microfabricated separation column (µSC), a Photoionization Detector (PI-D), and a flow controller unit are integrated with the modular hardware and software to realize a fully functional Vacuum Outlet µGC system. We have designed a novel auto-calibration method for temperature calibration of the microfabricated devices which does not require changing the electronic circuitry or reprogramming the device. The vacuum outlet µGC setup is tested with various mixture of analytes. For these experiments, an average relative standard deviation (RSD) for retention time repeatability of 2.5% is achieved. Data processing techniques for raw chromatograms, including baseline correction and peak detection, are implemented on a microcontroller board and tested extensively as a part of this work. A novel algorithm for multidimensional analysis for the identification of co-eluting compounds in complex samples is implemented with a prediction accuracy of 94%. / Master of Science / Toxic volatile organic compounds (VOCs) such as benzene and toluene found in gasoline and xylene used in ink, rubber, and leather industries are of concern as they are present at elevated concentrations due to their higher vapor pressure. Sufficient exposure to these toxicants, even at lower concentrations like 100 parts-per-billion-volume (ppbv), may cause adverse health effects. Gas Chromatography (GC) has been the established method for assessing the presence and concentration of VOCs in the environment. Traditional GC systems are bulky, power-hungry, expensive, and require expert supervision for analysis. Recent research in microelectromechanical systems (MEMS) has reduced the size of the GC components, also called micro-GC (µGC), while improving the performance. The majority of the research and development of µGC is aimed at advancing microfabricated components such as preconcentrators, separation columns, and gas detectors. However, the integration of these different components is an important topic that requires more investigation. In this thesis, we present a robust and scalable software and hardware architecture that can be used to develop a portable and modular µGC system. The thesis discusses different experiments to calibrate various microfabricated devices, which are then used to build a fully modular µGC system. We show the separation capacity of the modular µGC system by passing complex compounds like kerosene and diesel. As the chromatogram from the µGC system has noise, the second part of the thesis explores data analysis techniques such as baseline correction, peak detection. These data analysis tools are used to filter the noise, detect relevant peaks in the chromatograms, and identify the compounds in a complex sample.

Thèse numérisée par la Direction des bibliothèques de l'Université de Montréal.

Microorganisms swimming in their natural habitat interact with debris and boundaries, which can modify their swimming characteristics. However, the boundary effect on swimming microorganisms have not been completely understood yet, and is one of most active areas of research. Amongst microorganisms, unicellular ciliates are the fastest swimmers and also respond to a variety of external cues. We choose Paramecium multimicronucleatum as a model system to understand the locomotion of ciliates. First, we explore the effects of boundaries on swimming modes of Paramecium multimicronu- cleatum by introducing them in 2D films and 1D channels. The geometric confinements cause the Paramecia to transition between: a directed, a meandering and a self-bending behaviors. During the self-bending mode the cell body exerts forces on the walls; which is quantified by using a beam bending analogy and measuring the elasticity of the cell body. The first inves- tigation reveals the complicated swimming patterns of Paramecium caused by boundaries. In the second study we investigate the directed swimming of Paramecium in cylindrical capillaries, which mimics the swimming of ciliates in the pores of soil. A finite-sized cell lo- comoting in extreme confinements creates a pressure gradient across its ends. By developing a modified envelop model incorporating the confinements and pressure gradient effects, we are able to predict the swimming speed of the organisms in confined channels. Finally we study how Paramecium can swim and feed efficiently by stirring the fluid around its body. We experimentally employ "-Particle Image Velocimetry to characterize flows around the freely swimming Parameicum and numerically use Boundary Element Method to quantify the effect of body shapes on the swimming and feeding process. Results show that the body shape of Paramecium (slender anterior and bulky posterior) is hydrodynamically optimized to swim as well as feed efficiently. The dissertation makes significant advances in both experimentally characterizing and the- oretically understanding the flow field and locomotion patterns of ciliates near solid bound- aries. / Ph. D.

Sociality is one of the most fundamental aspects of being human. The key to sociality is coordination, that is, the bringing of people "into a common action, movement or condition" [134]. Coordination is, at base, how social creatures get social things done in the world. Being social creatures, we engage in highly coordinative activities in everyday life"two girls play hopscotch together, a group of musicians play jazz in a jam session and a father teaches a son how to ride a bicycle. Even mundane actions such as greetings, answering a phone call, and asking a question to ask a question by saying "Can I ask you a question?" are complex and intricate. Actors not only need to plan and perform situated actions, but also need to process the responding actions----even unforeseen ones----from the other party in real time and adjust their own subsequent actions. Yet, we expertly coordinate with each other in performing highly intricate coordinative actions. In this work, I look at how people coordinate joint activities at the moment of interaction and aim to unveil a range of coordinative issues, using "methodologies and approaches that fundamentally question the mainstream frameworks that define what counts as knowledge" (p.2, [80]) in the field of Computer Supported Cooperative Work (CSCW). To investigate computer mediated interactions among co-located people, I examine different interactional choices people make in the course of carrying out their joint activities, and the consequences of their choices. By investigating co-located groups as they played a collaborative, problem-solving game using distributed technologies in experimental settings, I (1) provide critical case reports which question and challenge non-discussed, often-taken-for-granted assumptions about face-to-face interactions and coordination, and (2) tie the observations to the creation of higher level constructs which, in turn, can affect subsequent design choices. More specifically, I ran two studies to look at how co-located people coordinate and manage their attention, tasks at hand, and joint activities in an experimental setting. I asked triads to work on a Sudoku puzzle collectively as a team. I varied support for the deictic mechanism in the software as well as form factors of mediating technology. My research findings show that: (1) different tools support different deictic behaviors. Explicit support for pointing is desirable to support complex reference tasks, but may not be needed for simpler ones. On the other hand, users without sophisticated explicit support may give up the attempt to engaged in complex reference. (2) talk is diagnostic of user satisfaction but lack of talk is not diagnostic of dissatisfaction. Therefore, designers must be careful in their use of talk as a measurement of collaboration. (3) the more people talk about complex relationships in the puzzle, the higher their increase in positive emotion. Either engaging with the problem at hand is rewarding or having the ability to engage with the problem effectively enough to speak about it is engaging. (4) amount of talk is related to form factor. People in both computer conditions talked less about the specifics oF the game board than people in the paper condition, but only people in the laptop condition experienced a significant decrease in positive emotion. (5) different mediating technologies afford different types of non-response situations. The most common occurrences of non-responses were precipitated by speakers talking to themselves in the computer conditions. Participants did not talk to themselves much in the paper condition. Differences in technology form factors may influence people's behaviors and emotion differently. These findings represent a portrait of how different technologies provide different interactional possibilities for people. With my quantitative and qualitative analyses I do not make bold and futile claims such as "using a highlighter tool will make users collaborate more efficiently," or "making people talk more will make the group perform better." I, instead, illustrate the interactional choices people made in the presence of given technological conditions and how their choices eventuated in situ. I then propose processlessness as an idea for preparing designs that are open to multiple interactional possibilities, and nudgers as an idea for enabling and aiding users to create and design their own situated experiences. / Ph. D.