This thesis focuses on the seismic performance of unreinforced masonry wall perforated with a door opening representing typical URM walls of many aged masonry buildings in Indonesia. To obtain a test result that will be able to represent the local conditions, the experiments have been conducted in the Research Institute for Human Settlements (RIHS) laboratory in Bandung-Indonesia. Two 75 % unreinforced masonry (URM) walls with a 1½-wythe of solid clay-brick were constructed in Dutch bond configuration and tested until failure under quasi-static-reversed cyclic loading. Both units were loaded vertically by constant loads representing gravity loads on the URM wall’s tributary area. Both models were constructed using local materials and local labours. Two features were taken into account. First, it accommodated the influence of flanged wall and second, the URM wall was built on the stone foundation. The first URM wall represent the plain existing URM building in Indonesia and second strengthened by Kevlar fibre. It was observed from the test results that the URM wall Unit-1 did not behave as a brittle structure. It could dissipate energy without loss of strength and had a post-elastic behaviour in terms of “overall displacement ductility” value of around 8 to 10. As predicted, the masonry material was variable and non homogeneous which caused the hysteresis loop to be non symmetrical between push and pull lateral load directions. It can be summarized that Kevlar fibre strengthening technique is promising and with great ease of installation. Although Kevlar material is more expensive when compared to other fabrics as long as it was applied at the essential locations and in limited volumes, it can significantly increase the in-plane URM wall capacity. With appropriate arrangements of Kevlar fibre, a practicing engineer will be able to obtain a desired rocking mechanism in the masonry structure. Another advantage for the architectural point of view, very thin Kevlar fibres do not reduce the architectural space. Studies have also been undertaken to analyze the in-plane response of plain URM wall before and after retrofiting using the current seismic standard and the Finite Element Method (FEM).

Relatively few research efforts have focused on splice length requirements for reinforced masonry, despite the significant impact of these requirements on the safety, economy, and constructability of masonry walls. The Canadian masonry provisions for splice lengths in CSA S304.1-04 are taken directly from the Canadian concrete design standard, CSA A23.3-04, and thus do not necessarily reflect factors unique to masonry construction. Provisions in American masonry standard TMS 402-13/ACI 530-13/ASCE 5-13 are based on test results of double pullout specimens, but may be overly conservative due to shortcomings of the specimen type chosen. The purpose of this study is to examine the splice lengths needed for flexural masonry elements reinforced with bar sizes typically used in Canadian masonry construction. In this study, 27 wall splice specimens and 12 double pullout specimens were constructed. The wall splice specimens were tested horizontally in four point loading, while the double pullout specimens were tested in direct tension. Results from the double pullout specimen testing suggest that the techniques used at the University of Saskatchewan (U of S) are reasonably similar to those of the National Concrete Masonry Association (NCMA), and are thus adequate to assess current provisions in the American and Canadian standards. A predictive equation for the tensile resistance of spliced reinforcement was developed from the results of the wall splice specimen testing. This predictive equation was then adjusted to incorporate an adequate margin of safety for calculating splice length requirements for design purposes, using a five percent quantile approach. The adjusted predictive equation was then extrapolated to determine the splice lengths corresponding to the nominal yield strength of the reinforcement. These splice lengths were compared to current code provisions. It was found that the current CSA S304.1-04 Class B provisions, used almost exclusively in construction, are conservative for No. 15, 20, and 25 bars. In contrast, the TMS 402-13 provisions were overly conservative for all three bar sizes. Changes to the bar size factors of the current provisions for both codes were recommended to bring better consistency to the requirements of the two codes, and thus ensure the safety, economy, and constructability of masonry walls.

In September of 2011 Zuccotti Park, located in the heart of downtown Manhattan, became a site of political contestation when several hundred activists pitched their tents, set up their signs, and began to occupy the park, in what later became known as Occupy Wall Street. Occupy Wall Street became part of the larger Occupy moment, in which public parks in most major cities and college towns across the nation were occupied for several months by protestors contesting a range of issues including the growing disparity in wealth, corporate influence on democracy, and deepening social injustices. By the end of 2011 the nationwide eviction of most Occupy encampments resulted in the assumed failure of Occupy to challenge successfully contemporary politics and to organize a clear list of demands. In this thesis, I draw on ethnographic material collected in 2012 to interpret the spatial strategies and spatialities of Occupy and argue that for Occupy, this lack of focus is a strength in that it creates a space for alternative political discussions and practices otherwise less visible or nonexistent in the current political system. I examine the spatialities of Occupy, by which I mean the networks, mobilities, and places of Occupy, and argue that such an analysis offers an entry point in which to consider the ways in which space and politics are co-produced. In order to examine the relations between space and politics, I locate the specific spatial practices and strategies utilized by participants both in the highly visible occupation of public parks and direct actions and less visible organization spaces.

Feature-based spectrum sensing techniques have emerged as good balance between energy-based techniques and coherent-based techniques, where the former require minimal prior information of the observed signal, and the latter have robust detection performance when the observed signal is very weak. In this thesis, we focus on pilot tone-aided detection as a feature-based detection class. We propose an improved pilot tone-aided spectrum sensor that utilizes the presence of the pilot tone and the overall energy of the received signal. We show that the optimal Neyman-Pearson detector is a weighted summation of a feature-based component and an energy-based component. The former provides coherent gains at the low signal-to-noise ratio (SNR) regime, whereas the latter provides non-coherent gains at moderate SNR levels. The proposed detector intelligently adapts its weights based on the SNR of the observed signal and the power allocation factor of the pilot tone. This helps it attain significant performance gains compared with the conventional pilot tone-aided detectors. In addition, we present suboptimal detectors that reduce the computational complexity. For instance, we demonstrate that moment estimators are effective techniques for spectrum sensing. Motivated by insights gained from the derivations of these moment estimators, we present a selective mean-variance estimator that performs well in the absence of the prior knowledge about the pilot tone. Moreover, we analyze the impact of two model uncertainties on the detection performance of the proposed detector: Noise uncertainty and imperfect pilot-matching. We show that unlike the energy detector, the proposed detector does not suffer from the SNR wall under the noise uncertainty model due to the coherent gains embedded in the feature-based component. Also, unlike existing pilot tone-aided detectors, the proposed detector is resilient against imperfect synchronization due to the non-coherent gains embedded in computing the overall energy of the signal. Also, we show that the proposed detector achieves the lowest sample complexity, leading to tangible improvements to the aggregate throughput of the secondary user. Extensive simulation and analytical results are provided to verify these conclusions. / Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2014-04-15 15:31:27.253

The performance of plastered straw bale walls with respect to wind-driven rainfall was investigated in this thesis. The absorption coefficient, which describes the rate of water infiltration, was measured for 14 plaster types, twelve different earth plasters and cement and lime plasters. The absorption coefficient was measured during uptake of water from a free reservoir. The effective porosity of these plasters, which describes the moisture storage capacity and the degree of protection that a plaster offers to straw bales, was also determined by submersion in water. An analytical model employing the absorption coefficient, the effective porosity, and climatic data was used to predict and compare plaster performance and to demonstrate the usefulness of this type of data. Simulated wind-driven rainfall experiments were also conducted on two plaster types. The results indicate that the static test used to measure the absorption coefficient can reasonably be used to predict actual wind-driven rainfall infiltration.

This thesis is an experimental study of turbulent flows over smooth and rough walls in a channel that consists of an upstream parallel section to produce a fully developed channel flow and a diverging section to produce an adverse pressure gradient (APG) flow. The roughness elements used were two-dimensional square ribs of nominal height k = 3 mm. The ribs were secured to the lower wall of the channel and spaced to produce the following three pitches: 2k, 4k and 8k, corresponding to d-type, intermediate and k-type rough walls, respectively. For each rough wall type, the ribs were inclined at 90°, 45° and 30° to the approach flow. The velocity measurements were performed using a particle image velocimetry technique. The results showed that rib roughness enhanced the drag characteristics, and the degree of enhancement increased with increasing pitch. The level of turbulence production and Reynolds stresses were significantly increased by roughness beyond the roughness sublayer. It was observed that the population, sizes and the level of organization of hairpin vortices varied with roughness and more intense quadrant events were found over the smooth wall than the rough walls. APG reinforced wall roughness in augmenting the equivalent sand grain roughness height, turbulence production and Reynolds stresses. APG also reduced the sizes of the hairpin packets but strengthened the quadrant events in comparison to the results obtained in the parallel section. The secondary flow induced by inclined ribs significantly altered the distributions of the flow characteristics across the span of the channel. Generally, the mean flow was less uniform close to the trailing edge of the ribs compared to the flows at the mid-span and close to the leading edge of the ribs. The Reynolds stresses and hairpin packets were distinctly larger close to the trailing edge of the ribs. Rib inclination also decreased the drag characteristics and significantly modified the distributions of the Reynolds stresses and quadrant events. In the parallel section, the physical sizes of the hairpin packets were larger over 45° ribs whereas in the diverging section, the sizes were larger over perpendicular ribs.

Nowadays, cancer treatment and tissue regeneration have attracted large amount of attention. Single Wall Carbon Nanotubes (SWNT) possess large surface area and outstanding optical and electrical performance, making it a promising component in cancer therapy and tissue reengineering systems. In this study, four disease treating systems based on SWNT are developed. They are pH-sensitive poly(ethylene glycol)-doxorubicin(PEG-DOX)@SWNT drug release system, temperature sensitive SWNT hydrogel, SWNT based biocompatible magnetic hydrogel and biocompatible SWNT-gelatin-F127-cysteamine hydrogel for tissue engineering. The successfully synthesized target compounds are characterized by FTIR. The in vitro release of drugs from the drug release systems is evaluated upon changes of pH values and the laser scanning. The effect of cancer treatment systems on specific kind of cells are examined by confocal laser scanning microscopy (CLSM). The results indicate that all of the four systems show great potential in the biomedical applications especially in disease therapy applications.

This thesis presents a computational analysis of multi-element guard-heated sensors designed to overcome the most severe limitation of conventional thermal sensors for wall shear stress (WSS) measurement in turbulent flows –that of indirect heat conduction through the substrate. The objectives of this thesis are the study of guard-heated sensors {i} to quantify the reduction, over conventional single-element sensors, of substrate heat conduction losses and resultant errors over a range of applied shear and {ii} to examine a range of values of guard heater geometric parameters, in two common fluids, air and water and identify the best designs. Wall-turbulence, the turbulent flow in the vicinity of solid boundaries, has proved difficult to model accurately, due to the lack of accurate WSS measurements. Examples of areas of impact are drag force reduction on transport vehicles in land, sea, air, which today largely translate to reduced fossil fuel use and dependence; aerodynamic noise and control for flight and for wind energy conversion; atmospheric and oceanic transport studies for weather, climate and for pollutant transport; riverbank erosion. Constant-temperature anemometry with MEMS devices, flush-mounted hot-film thermal sensors, is non-intrusive, affords the best temporal resolution and is well-established. However, these hot-film probes suffer from unwanted heat transport to the fluid through the substrate, with errors and nonlinearity large enough to overwhelm quantitative utility of the data. Microfabrication techniques have enabled multi-element guard-heated prototypes to be fabricated. Our results show that errors in sensing-element signals, contributing to spectral distortion, are sensitive to sensor location within the guard heater. These errors can be reduced to below 1% of the signal with proper location of the sensor. Guard heating also reduces the large variation in spatial averaging due to substrate conduction. This makes them suitable for turbulent flows with a large range of fluctuations. / Graduate

No description available.

The Ornate Tinamou (Nothoprocta ornata), an ancient bird, has adapted to life at high altitude (>2.400 m.a.s.l) for a longer period than the domestic chicken (Gallus domesticus), which came to South America with the Spanish conquerors. Ornate tinamous have a smaller heart in relation to body size than domestic chickens. This study was made to evaluate heart morphometric measurements comparing Ornate Tinamou and domestic chicken using echocardiography measurements to determine wall thickness and chamber size and to evaluate whether it can retrieve measurements consistent with previous results on dissected hearts. I was also interested in evaluating potential adaptations of the Ornate Tinamou to life in hypoxic environments by exposing the heart to positive inotropic stimulation. The results were compared with those previously obtained on dissected hearts. The results showed that the chamber size of the domestic chicken was significantly larger than in Ornate Tinamou, both in conscious and anesthetized birds. Injection of 1µg/kg isoproterenol caused domestic chickens’ systolic chamber size to decrease significantly and fractional shortening to increase significantly. The same changes were seen in the Ornate Tinamou but they were not significant. In conclusion, this study confirms that echocardiography is a valid method for retrieving cardiac measurements without euthanizing animals, opening for the possibility of taking several measurements at different ages.