Architecture should strive to create a dialogue between the history of architecture and its future. This dialogue is really a mosaic of interconnections formed by our conceptions of context and order. These interconnections strive to be transparent so as to introduce a level of complexity that allows for a multitude of readings and is in constant variation as provided by the site, the inhabitants and the building. It is thru these transparent interconnections that dialogue is enriched. The project has been driven by a reciprocal struggle between specific site conditions, and the development of tectonic pieces that order, clarify and sometimes veil a larger whole. Whose end is to connect with a larger whole and elevate its seemingly simple pieces to a level of complexity that is greater than the sum of those parts. / Master of Architecture

This thesis aimed to design and develop a novel micro-thermal electric generator (£g-TEG) with a transparent parallel-array bridge microstructure using the ANSYS finite element analysis software and Micro Electro Mechanical Systems (MEMS) technology. The presented £g-TEG can convert the temperature difference between the indoor and outdoor planes of building glass window into a useful electrical power. The thermoelectrically transferred output electrical power is suitable for recharging various mobile communication products. Conventional £g-TEG presented a high fabrication cost, low integration compatibility with IC processes and non-transparent characteristics. To improve these disadvantages, this research utilizes a batch production surface micromachining technology to implement the Poly-Si based parallel-array £g-TEG on a transparent quartz glass substrate and the main fabrication processes adopted in this research are including six thin-film deposition processes and five photolithography processes. The implemented Poly-Si based transparent £g-TEG has successfully demonstrates a maximum temperature difference of 1.38¢J between the hot plane (substrate) and cold plane (suspending microstructure), a maximum output voltage of 13.28 mV/cm2, a maximum output power of 110.22 nW/cm2 and a maximum light transmission of 40%.

We analyze an interdiction problem in which a nuclear-material smuggler can traverse the rail and road ports of entry (POEs) along the Mexican and Canadian borders of the United States. Our objective is to determine the optimal locations of a limited number of transparent and non-transparent assets so as to minimize the smuggler’s total probability of evasion, from origin to destination. We choose origins in Mexico and Canada and give the smuggler a diverse set of destinations to choose from. Our analysis aims to provide a complete prioritization and picture of the threat at Mexican and Canadian POEs, leading to insight into practical locations for transparent and non-transparent assets. / text

Transparent conducting oxides (TCOs) have become an integral part of modern life through their essential role in touchscreen technology. The growing demand for cheap and superior transparent conducting layers, primarily driven by the smart phone market, has led to renewed efforts to develop novel TCOs. Currently, the most widely used material for transparent conducting applications is Sn-doped indium oxide (ITO), which has outstanding optical and electrical properties. This material is expensive though, due to the extensive use of In, and efforts to develop new low-cost transparent conducting oxides (TCO) have become increasingly important. Similarly attempts to reduce the cost of the fabrication and post-sintering steps used in making doped metal oxide thin films through innovative technologies have gained a lot of attention. With these points in mind, this research project has focused on the development of a novel low-cost aerosol assisted physical deposition method for TCO thin film fabrication and the development of new highly conducting materials to replace the expensive ITO for TCO applications. In this study, a new and simple aerosol assisted vapour deposition technique (i.e AACT) is developed to fabricate TCO films using TCO nanoparticle suspensions. Firstly, to test the validity of the method, ITO thin films are fabricated on float glass substrates from a nanoparticle suspension. The influence of the deposition parameters on the structural and opto-electronic properties of the thin films are investigated to understand the intricacies of the process. In order to investigate the fabrication of replacement materials for ITO, a range of doped zinc oxide powders are synthesised and processed using microwave radiation. Nominally, Al doped ZnO (AZO), Ga doped ZnO (GZO), Si doped ZnO (SZO), Cu doped ZnO (CZO) and Mn doped ZnO (MZO) singly doped ZnO powders are all investigated to determine the best metal dopants for transparent conducting ZnO. AZO and GZO pellets are found to present the best electrical conductivity for the singly doped microwave fabricated powders with values of 4.4 x 10-3 and 4.3 x 10-3 Ω.cm achieved reproducibly. In an effort to further improve the properties of ZnO, co-doping experiments, utilising the two best dopants from the previous work (i.e. Al and Ga) is investigated. ZnO structures that are co-doped with Al and Ga (AGZO) are found to exhibit significantly enhanced electrical properties than the singly doped powders. Typically, electrical conductivity value of 5.6 x 10-4 Ω.cm is obtained for AGZO pellets, which is an order of magnitude better than the previously fabricated materials. Finally, the best AZO, GZO and AGZO materials are utilised to fabricate thin films using the previously verified AACT technique. Further investigations into the opto-electrical properties of the resulting thin films is presented prior to the utilisation of the best films in a practical application. Transparent heaters are fabricated using the best AGZO thin films, which are capable of reaching a mean temperature of 132.3 °C after applying a voltage of 18 V for 10 min. This work highlights the potential for using highly conducting AGZO, particularly fabricated by the microwave synthesis route, as a potential alternative for ITO in a wide variety of applications. The research also highlights the advantages of using microwaves in the thermal processing of TCO materials which significantly reduces the energy impact of the production process.

Les problèmes associés au transport sédimentaire sont l'une des préoccupations majeures de notre société, tant d'un point de vue environnemental qu'économique. Nous disposons de peu d'informations sur la dynamique locale des phénomènes d'érosion et plus particulièrement pour les sédiments cohésifs. Dans cette étude, nous nous focalisons sur les phénomènes locaux agissant à l'interface eau-sédiment. Tout d'abord, un sédiment modèle transparent est réalisé en nous basant sur les propriétés rhéologiques des sédiments naturels. Pour cela, différents mélanges, à base de Laponite et de carboxyméthylcellulose, sont testés en faisant varier la concentration et le mode de fabrication. Les protocoles de mesures sont alors établis et une loi d'évolution des propriétés en fonction de la concentration en sédiment est déterminée. Puis, la qualification de la veine hydraulique de l'étude, sans présence de sédiment, est réalisée par des mesures optiques PIV. L'obtention des champs de vitesse moyens et instantanés nous a permis de calculer l'énergie cinétique turbulente ainsi que les contraintes laminaires et turbulentes agissant sur le fond. Enfin, des mesures similaires sont effectuées dans le canal en présence de sédiment pour des cas où le sédiment est entraîné ou non par les forces hydrodynamiques. L'accès à l’énergie cinétique turbulente ainsi qu'aux contraintes laminaires et turbulentes hydrodynamiques permet de comprendre les phénomènes locaux étant à l’origine de l'érosion. Les contraintes à l'interface sont comparées à celles obtenues dans le sédiment via la loi rhéologique mettant en évidence la présence d'une contrainte de cisaillement critique liée aux propriétés du sédiment. / Associated problems with sediment transport are one of the major concerns of our society, as an environmental and economic perspective. Few information about local dynamics of erosion is available and especially for cohesive sediments. In this study, we focus on local phenomena acting at the water-sediment interface. First, a transparent sediment model is made based on rheological properties of natural sediments. For this purpose, different mixtures, containing Laponite and carboxymethylcellulose, are tested by varying the concentration and method of manufacture. Measurement protocols are then established and a law of variation of rheological properties as a function of the sediment concentration is determined. Then, definition of flow within the hydraulic channel of the study, without the presence of sediment, is obtained by PIV optical measurements. Average and instantaneous velocity fields allowed us to calculate the turbulent kinetic energy and the laminar and turbulent stresses acting on the bottom. Finally, similar measurements are carried out in the channel with presence of sediments in cases where the sediment is driven or not by hydrodynamic forces. Access to the turbulent kinetic energy as well as laminar and turbulent hydrodynamic stresses provides an understanding of local phenomena causing erosion. Stresses at the interface are compared with those obtained within the sediment via the rheological law highlighting the presence of a critical shear stress related to the sediment properties.

Les travaux de recherche effectués lors de cette thèse s'articulent autour de deux matériaux carbonés: les nanotubes de carbone et le graphène. Leur point commun réside dans la technique de mise en suspension qu'est la dissolution douce. Cette méthode se base sur la réduction des nanostructures carbonées en polyélectrolytes, autrement dit en nanostructures chargées négativement. Nous nous sommes intéressés d'une part à la préparation et à l'étude de films transparents conducteurs à base de nanotubes de carbone pour des applications en électronique organique en tant qu'électrode transparente et en électrochimie. D'autre part, les travaux présentent une étude des solutions de graphène. Nous nous sommes notamment attachés à démontrer la présence de graphène en suspension dans certains solvants organiques par analyse directe de ces solutions. / Two carbon materials have been studied during this thesis: carbon nanotubes and graphene. Their common point is the method used to prepare suspensions which is the mild dissolution. Using this method, carbon nanostructures can be reduced into polyelectrolytes, id. into negatively charged nanostructures. The first part deals with transparent and conductive films of carbon nanotubes which have been prepared and studied as transparent electrode for electronic applications and for electrochemistry. The second part of this work deals with graphene in solution in different solvents. The aim of this work was to show the presence of graphene by direct analysis of these graphene solutions.

Transparent oxide electronics have emerged as promising materials to shape the future of electronics. While several n-type oxides have been already studied and demonstrated feasibility to be used as active materials in thin film transistors, high performance p-type oxides have remained elusive. This dissertation is devoted to the study of transparent p-type oxide semiconductor tin monoxide and its use in the fabrication of field effect devices. A complete study on the deposition of tin monoxide thin films by direct current reactive magnetron sputtering is performed. Carrier density, carrier mobility and conductivity are studied over a set of deposition conditions where p-type conduction is observed. Density functional theory simulations are performed in order to elucidate the effect of native defects on carrier mobility. The findings on the electrical properties of SnO thin films are then translated to the fabrication of thin films transistors. The low processing temperature of tin monoxide thin films below 200 oC is shown advantageous for the fabrication of fully transparent and flexible thin film transistors. After careful device engineering, including post deposition annealing temperature, gate dielectric material, semiconductor thickness and source and drain electrodes material, thin film transistors with record device performance are demonstrated, achieving a field effect mobility >6.7 cm2V-1s-1. Device performance is further improved to reach a field effect mobility of 10.8 cm2V-1s-1 in SnO nanowire field effect transistors fabricated from the sputtered SnO thin films and patterned by electron beam lithography. Downscaling device dimension to nano scale is shown beneficial for SnO field effect devices not only by achieving a higher hole mobility but enhancing the overall device performance including better threshold voltage, subthreshold swing and lower number of interfacial defects. Use of p-type semiconductors in nonvolatile memory applications is then demonstrated by the fabrication of hybrid ferroelectric field effect transistors composed of organic ferroelectric layer polyvinylidene fluoride trifluoroethylene and inorganic p-type semiconductor tin monoxide. Both rigid and flexible devices are demonstrated, showing the advantages of low temperature oxides over polymer semiconductors by achieving much better performance, such as order of magnitude higher hole mobility.

With more than 5 billion users globally, mobile devices have become ubiquitous in our daily life. The modern mobile handheld device is capable of providing many multimedia services through a wide range of applications over multiple networks as well as on the handheld device itself. These services are predominantly driven by data, which is increasingly associated with sensitive information. Such a trend raises the security requirement for reliable and robust verification techniques of users.This thesis explores the end-user verification requirements of mobile devices and proposes a novel Behaviour Profiling security framework for mobile devices. The research starts with a critical review of existing mobile technologies, security threats and mechanisms, and highlights a broad range of weaknesses. Therefore, attention is given to biometric verification techniques which have the ability to offer better security. Despite a large number of biometric works carried out in the area of transparent authentication systems (TAS) and Intrusion Detection Systems (IDS), each have a set of weaknesses that fail to provide a comprehensive solution. They are either reliant upon a specific behaviour to enable the system to function or only capable of providing security for network based services. To this end, the behaviour profiling technique is identified as a potential candidate to provide high level security from both authentication and IDS aspects, operating in a continuous and transparent manner within the mobile host environment.This research examines the feasibility of a behaviour profiling technique through mobile users general applications usage, telephone, text message and multi-instance application usage with the best experimental results Equal Error Rates (EER) of 13.5%, 5.4%, 2.2% and 10% respectively. Based upon this information, a novel architecture of Behaviour Profiling on mobile devices is proposed. The framework is able to provide a robust, continuous and non-intrusive verification mechanism in standalone, TAS or IDS modes, regardless of device hardware configuration. The framework is able to utilise user behaviour to continuously evaluate the system security status of the device. With a high system security level, users are granted with instant access to sensitive services and data, while with lower system security levels, users are required to reassure their identity before accessing sensitive services.The core functions of the novel framework are validated through the implementation of a simulation system. A series of security scenarios are designed to demonstrate the effectiveness of the novel framework to verify legitimate and imposter activities. By employing the smoothing function of three applications, verification time of 3 minutes and a time period of 60 minutes of the degradation function, the Behaviour Profiling framework achieved the best performance with False Rejection Rate (FRR) rates of 7.57%, 77% and 11.24% for the normal, protected and overall applications respectively and with False Acceptance Rate (FAR) rates of 3.42%, 15.29% and 4.09% for their counterparts.

Recent advances in third generation photovoltaics, particularly the rapid increase in perovskite power conversion efficiencies, may provide a cheap alternative to silicon solar cells in the near future. A key component to these devices is the transparent front electrode, and in the case of Dye Sensitized Solar Cells, it is the most expensive part. A lightweight, cost-effective, robust, and easy-to-fabricate new generation TCE is required to enable competition with silicon. Indium Tin Oxide, commonly used in touchscreen devices, Organic Light Emitting Diodes (OLEDs), and thin film photovoltaics, is widely used and commonly referred to as the industry standard. As the global supply of indium decreases and the demand for this TCE increases, a similar alternative TCE is required to accompany the next generation solar cells that promise energy with lighter and significantly cheaper modules. This alternative TCE needs to provide similar sheet resistance and optical transmittance to ITO, while also being mechanically and chemically robust. The work in this thesis begins with an exploration of several synthesized ITO replacement materials, such as copper nanowires, conductive polymer PEDOT:PSS, zinc oxide thin films, reduced graphene oxide and combinations of the above. A guiding philosophy to this work was prioritizing cheap, easy deposition methods and overall scalability. Shortcomings of these TCEs were investigated and different materials were hybridized to take advantage of each layers strengths for development of an ideal ITO replacement. For CuNW-based composite electrodes, ~85% optical transmittance and ~25 Ω/sq were observed and characterized to understand the underlying mechanisms for optimization. The second half of this work is an examination of many different perovskite synthesis methods first to achieve highest performance, and then to integrate compatible methods with our CuNW TCEs. Several literature methods investigated were irreproducible, and those that were successful posed difficulties integrating with CuNW-based TCEs. Those shortcomings are discussed, and how future work might skirt the issues revealed here to produce a very low cost, high performance perovskite solar cell.

Clean and affordable energy, especially solar energy, is becoming more and more important as our annual total energy consumption keeps rising. However, to make solar energy more affordable and accessible, the cost for fabrication, transportation and assembly of all components need to be reduced. As a crucial component for solar cells, transparent conductive electrode (TCE) can determine the cost and performance. A light weight, easy-to-fabricate and cost-effective new generation TCE is thus needed. While indium-doped tin oxide (ITO) has been the most widely used material for commercial applications as TCEs, its cost has gone up due to the limited global supply of indium. This is not only due to the scarcity of the element itself, but also the massive production of various opto-electronic devices such as TVs, smartphones and tablets. In order to reduce the cost for fabricating large area solar cells, substitute materials for ITO should be developed. These materials should have similar optical transmittance in the visible wavelength range, as well as similar electrical conductivity (sheet resistance) to ITO. This work starts with synthesizing ITO-replacing nano-materials, such as copper nanowires (CuNWs), derivative zinc oxide (ZnO) thin films, reduced graphene oxide (rGO) and so on. Further, we applied various deposition techniques, including spin-coating, spray-coating, Mayer-rod coating, filtration and transferring, to coat transparent substrates with these materials in order to fabricate TCEs. We characterize these materials and analyze their electrical/optical properties as TCEs. Additionally, these fabricated single-material-based TCEs were tested in various lab conditions, and their shortcomings (instability, rigidity, etc.) were highlighted. In order to address these issues, we hybridized the different materials to combine their strengths and compared the properties to single-material based TCEs. The multiple hybridized TCEs have comparable optical/electrical metrics to ITO. The doped-ZnO TCEs exhibit high optical transmittance over 90% in the visible range and low sheet resistance under 200Ω/sq. For CuNW-based composite electrodes, ~ 85% optical transmittance and ~ 25Ω/sq were observed. Meanwhile, the hybridization of materials adds additional features such as flexibility or resistance to corrosion. Finally, as a proof of concept, the CuNW-based composite TCEs were tested in dye-sensitized solar cells (DSSCs), showing similar performance to ITO based samples.