The nature of the dark matter in the Universe is one of the greatest mysteries in modern astronomy. The neutralino is a nonbaryonic dark matter candidate in minimal supersymmetric extensions to the standard model of particle physics. If the dark matter halo of our galaxy is made up of neutralinos some would become gravitationally trapped inside massive bodies like the Earth. Their pair-wise annihilation produces neutrinos that can be detected by neutrino experiments looking in the direction of the centre of the Earth. The AMANDA neutrino telescope, currently the largest in the world, consists of an array of light detectors buried deep in the Antarctic glacier at the geographical South Pole. The extremely transparent ice acts as a Cherenkov medium for muons passing the array and using the timing information of detected photons it is possible to reconstruct the muon direction. A search has been performed for nearly vertically upgoing neutrino induced muons with AMANDA-B10 data taken over the three year period 1997-99. No excess above the atmospheric neutrino background expectation was found. Upper limits at the 90 % confidence level has been set on the annihilation rate of neutralinos at the centre of the Earth and on the muon flux induced by neutrinos created by the annihilation products.

Droplet splatter dynamics is an important study in the field of forensics since a crime event can produce many blood stains. Understanding the origins of the blood stains from pure observations is very difficult because much of the information about the impact is lost. A theoretical model is therefore needed to better understand the dynamics of droplet impact and splatter. We chose to explore a fluid modelling method known as Smoothed Particle Hydrodynamics (SPH) to determine whether it is capable of modelling droplet splatter accurately. Specifically, we chose to investigate an SPH version of a non-Newtonian pressure correction method with surface tension. Three experiments were performed to analyze the different aspects of SPH. From the results of the experiments, we concluded that this method can produce stable simulations if an artificial viscosity model is included, a third-order polynomial kernel is used and the pressure boundary condition on surface particles are non-zero. / UOIT

Conical fluidized bed dryers are widely used in the pharmaceutical industry due to their high heat and mass transfer characteristics. Despite their widespread use, very little is known about the hydrodynamics of conical fluidized bed dryers. Wet pharmaceutical granule has high moisture content and wide particle size distribution (PSD), which can lead to poor mixing and non uniform drying. Uneven moisture content in the final product can adversely affect the quality and shelf life of these high value drugs. Previous studies on the conical fluidized bed dryers focused on the study of the gas phase, however motion of particulate phase has never been studied. Particle tracking is an important tool to study the motion of the particulate phase. Two particle tracking techniques were developed and used to study the motion of the particulate phase in a conical fluidized bed dryer. The first technique was radioactive particle tracking (RPT) which was developed at the University of Saskatchewan laboratory for a vessel having conical geometry. Experiments were conducted using dry pharmaceutical granule and during the actual drying of wet pharmaceutical granule. Two radioactive tracers of different sizes (1.6 to 2.6 mm) were tracked in each set of experiments to determine the effect of particle size on particle motion and particle mixing. Superficial gas velocities of 1, 1.5, 2 and 2.5m/s were used in dry bed studies to quantify the effect of superficial gas velocity. The second particle tracking technique was developed at the labs of Merck Frosst Canada Inc. Movies were captured using a high speed video camera coupled to a borescope and then analyzed off-line using image analysis software.Three powders having mean particle diameters of 774, 468 and 200 microns were used. Experiments were conducted at superficial gas velocities of 1.5, 2 and 3 m/s. <p>RPT revealed that there is a distinct circulation pattern of the particulate phase. Particles move upwards at high velocities near the centre of the bed and fall slowly near the walls. Furthermore, most of the gas flow is concentrated near the centre of the bed and the circulation pattern was observed at all the superficial gas velocities. Particle size of the tracer particle and PSD of the bed material had an appreciable impact on particle mixing with bigger particles exhibiting higher segregation tendencies than the smaller ones in the case of dry granule having a broad PSD. Particle segregation due to size difference was more pronounced at a superficial gas velocity of 1 m/s. However, segregation decreased with an increase in superficial gas velocity. During drying of wet granule, particle mixing and motion of the tracer particle was poor during the first 7 minutes of drying suggesting that most of the gas flow was concentrated near the centre of the bed. Particle mixing and average particle speeds increased considerably when the moisture content in the granule was less than 18 wt% suggesting a change in the hydrodynamics of the bed with the gas being more evenly distributed throughout the bed. Image analysis of high speed movies also suggested that a dilute region existed at the center of the bed. These observations were in agreement with the observations made by RPT.

The increased market for navigation, localization and mapping system has encouraged the research to dig deeper into these new and challenging areas. The remarkable development of computer soft- and hardware have also opened up many new doors. Things which more or less where impossible ten years ago are now reality. The possibilities of using a mathematical approach to compensate for the need of expensive sensors has been one of the main objectives in this thesis. Here you will find the basic principles of localization of indoor UAVs using particle filter (PF) and Octomaps, but also the procedures of implementing 2D scanmatching algorithms and quaternions. The performance of the algorithms is evaluated using a high precision motion capture system. The UAV which forms the basis for this thesis is equipped with a 2D laser and an inertial measurement unit (IMU). The results show that it is possible to perform localization in 2D with centimetre precision only by using information from a laser and a predefined Octomap.

Conical fluidized bed dryers are widely used in the pharmaceutical industry due to their high heat and mass transfer characteristics. Despite their widespread use, very little is known about the hydrodynamics of conical fluidized bed dryers. Wet pharmaceutical granule has high moisture content and wide particle size distribution (PSD), which can lead to poor mixing and non uniform drying. Uneven moisture content in the final product can adversely affect the quality and shelf life of these high value drugs. Previous studies on the conical fluidized bed dryers focused on the study of the gas phase, however motion of particulate phase has never been studied. Particle tracking is an important tool to study the motion of the particulate phase. Two particle tracking techniques were developed and used to study the motion of the particulate phase in a conical fluidized bed dryer. The first technique was radioactive particle tracking (RPT) which was developed at the University of Saskatchewan laboratory for a vessel having conical geometry. Experiments were conducted using dry pharmaceutical granule and during the actual drying of wet pharmaceutical granule. Two radioactive tracers of different sizes (1.6 to 2.6 mm) were tracked in each set of experiments to determine the effect of particle size on particle motion and particle mixing. Superficial gas velocities of 1, 1.5, 2 and 2.5m/s were used in dry bed studies to quantify the effect of superficial gas velocity. The second particle tracking technique was developed at the labs of Merck Frosst Canada Inc. Movies were captured using a high speed video camera coupled to a borescope and then analyzed off-line using image analysis software.Three powders having mean particle diameters of 774, 468 and 200 microns were used. Experiments were conducted at superficial gas velocities of 1.5, 2 and 3 m/s. <p>RPT revealed that there is a distinct circulation pattern of the particulate phase. Particles move upwards at high velocities near the centre of the bed and fall slowly near the walls. Furthermore, most of the gas flow is concentrated near the centre of the bed and the circulation pattern was observed at all the superficial gas velocities. Particle size of the tracer particle and PSD of the bed material had an appreciable impact on particle mixing with bigger particles exhibiting higher segregation tendencies than the smaller ones in the case of dry granule having a broad PSD. Particle segregation due to size difference was more pronounced at a superficial gas velocity of 1 m/s. However, segregation decreased with an increase in superficial gas velocity. During drying of wet granule, particle mixing and motion of the tracer particle was poor during the first 7 minutes of drying suggesting that most of the gas flow was concentrated near the centre of the bed. Particle mixing and average particle speeds increased considerably when the moisture content in the granule was less than 18 wt% suggesting a change in the hydrodynamics of the bed with the gas being more evenly distributed throughout the bed. Image analysis of high speed movies also suggested that a dilute region existed at the center of the bed. These observations were in agreement with the observations made by RPT.

Depth and temporal variability of organic carbon (POC) and total nitrogen (TN) and their isotopic compositions (£_13C and £_15N) in sinking particulate organic matter (POM) collected at the SEATS time-series station (18¢X15¡¦ N; 115¢X50¡¦ E), northern South China Sea, respond closely to the strong seasonality (changes in sea surface temperatures and mixed layer depths) in the surface layer, but are modified considerably by subsequent microbial degradation/remineralization and probably by re-suspension of sediments from the surrounding shelf region in the deep water. Lower C/N and £_15N in summer than the other seasons reflects the change of nutrient supply from NO3-rich, 15N-enriched subsurface waters to N2-fixation-dominated nitrogen source in the surface waters. Below the euphotic zone (>100m), both POC and TN decrease, whereas C/N increases progressively with depth owing to the biodegradation and the preferential removal of more degradable nitrogen-containing compounds through the water column. The C/N increase rate is estimated to be 0.4 unit per 1 km water depth, which is significantly higher than the world average (0.2/km) as a result of the input of higher C/N organic matter from sediments deposited nearby the SEATS site. POC and TN and total particulate mass fluxes decrease sharply within the euphotic zone and continue to decrease all way through the water column to seafloor. For site comparison and global synthesis, an average fraction (e-ratio) of 0.22 of POC exported from the euphotic zone and a POC attenuation rate (b value) of 0.97 are derived. Since the results of this study were obtained from a marginal sea characteristic of strong monsoonal modulation, they should contribute to a better understanding of the fate and pathway of POC in the world ocean.

Asian dust storms invaded Taiwan in springtime. During the Asian dust-storm periods, the dust particles suspended in the atmosphere could not only deteriorate the ambient air quality, mainly high particulate matter concentration and low visibility, but also cause severely adverse effects on human health. In this study, Asian dusts were sampled at Pencadores Islands and characterized the physical and chemical characteristics to investigate the influence of Asian dust storms. Due to its clean atmosphere, Pencadores Islands can be treated as one of the best air quality background sites in Taiwan. In this sampling campaign, five Asian dust storm episodes were observed at Pencadores Islands. Asian dusts transported to Taiwan along the east of China or the east ocean of China and invaded Taiwan from either the northeast or the northwest. The concentrations of atmospheric aerosols during Asian dust storm episodes were 2-3 times higher than the background level. The concentration of PM10 increased dramatically. The increase of PM10 concentration was mainly attributed to coarse particles. The ratio of coarse particles to fine particles for Asian dust storm periods was higher than those for non-Asian dust storm periods. From March to April, the concentration of PM10 increased due to sea-salt aerosol blow into atmosphere by strong eastwest monsoon. It suggested that, at Pencadores Islands, seawater was major chemical species of suspended particles. The concentration of F-, Cl-, Br-, NO3-, SO42-, Na+, Mg2+, and Ca2+ increased during Asian dust storm episodes indicated that pollutant would be transport by Asian dusts. The most possible chemical species in coarse particles would be MgSO4 and CaSO4. The carbon content of suspended particles increased dramatically. The increase of carbon content of coarse particles was mainly attributed to elemental carbon. The increase of carbon content of fine particles was mainly attributed to organic carbon from second reaction. The concentration of Al, K, Br-, Fe, and Ca increased during Asian dust storm episodes indicated that Asian dust storm would transport dusts to Pencadores Islands. The major pollution sources were mobile sources and dust sources at Pencadores Islands. During the Asian dust-storm periods, the percentages of industrial sources, seawater, and secondary aerosols increased dramatically.

Supersymmetric extensions to the Standard Model (SM) have many interesting experimental consequences which can provide important hints to the physics beyond the SM. In this thesis, we first study the anomalous magnetic moment of the muon and show that a significant constraint on the parameter space can be obtained from its current experimental value. In the next topic, we study the CP violations in B -> phi K decays and show that the SM and the minimal supergravity model (mSUGRA) cannot account for the current experimental observation. We then show that all the data can be accommodated for a wide range of parameters in models with non-universal soft breaking left-right A terms. In our last topic, which is based on a Horava-Witten inspired model proposed by R. Arnowitt and B. Dutta, we extend their analysis to the full fermion sector of the SM and propose a new mechanism different from the usual see saw mechanism to generate small neutrino masses which are in good agreement with the current neutrino oscillation data.

One of the distinguishing characteristics of hostile networked radio sources (e.g., enemy sensor network nodes), is that only physical layer information and limited medium access control (MAC) layer information of the network is observable. We propose a scheme to localize hostile networked radio sources based on the radio signal strength and communication protocol pattern analysis using a mobile robot with a directional antenna. We integrate a Particle Filter algorithm with a new sensing model which is built on a directional antenna model and Carrier Sense Multiple Access (CSMA)-based MAC protocol model. we model and analyze the channel idle probability and busy collision probability as a function of the number of radio sources in the CSMA protocol modeling. Based on the sensing model, we propose a particle-filter-based scheme to simultaneously estimate the number and the positions of networked radio sources. We provide a localization scheme based on the method of steepest descent for the purpose of performance comparison. Simulation results demonstrate that our proposed localization scheme has a better success rate than the scheme based on the steepest descent at different tolerant distances.

One of the primary concerns with space travel is the protection of astronauts from potentially lethal radiation. A major source of potentially lethal radiation is our own sun. During Solar Cycle 23 there were 97 detected Solar Particle Events (SPEs). In order to develop radiation protection guidelines and establish methods to protect astronauts the spectrum of particles emitted during a SPE must be understood. Data for oxygen and iron particle fluence was taken from the Solar Isotope Spectrometer. The fluence was sorted and formatted for each solar particle event. After determining the contribution to skin dose for oxygen, the time evolution of each event was analyzed. After analyzing the raw count data, a threshold was set that could be applied to each event. Using this threshold count rate as the starting point, each event was plotted and fitted with a smoothing polynomial function. The slope calculated from this function was then plotted against the previously calculated skin dose and a Weibull function was fitted to the data. The resulting plot provides a method to predict the cumulative dose due to the oxygen fluence over the first 24 hours of an event and thereby provide a warning of future high dose rate in time to achieve significant dose sparing for most events. For the ten events that delivered the highest oxygen dose, the dose sparing that could be achieved by taking shelter when the high dose rate was predicted was greater than 70 percent for all but one event. The one outlier achieved a dose paring of only 57 percent.