Measurements of gas volume fraction, bubble velocity, chord length and bubble size distributions were performed in the research vessel Athena II operating in Saint Andrew Bay in the gulf coast near Panama City, FL. Double tipped sapphire optical local phase-detection probes were used to acquire indicator functions downstream of the breaking bow wave, behind the masker and at the stern. These indicator functions were also taken at different depths, distances from the hull, operating speeds and headings respect to the waves. The data processing includes the computation of velocity of individual bubbles and chord lengths, resulting in chord length distributions. These chord length distributions are used to obtain bubble size distributions using a novel procedure described in detail. Uncertainty analysis is performed for gas volume fraction, average bubble velocity and chord length. The results indicate that air entrainment increases with ship speed and sailing against the waves at all positions. The bow wave exhibits unsteady breaking that creates bubble clouds, which were characterized and identified by signal processing. At the stern a very strong dependence of bubble size with depth was found, with evidence that bubbles smaller than 500 micrometers are transported through the bottom of the hull and reach the transom. The roller present at the transom, the associated strong unsteadiness and bubble entrainment are well captured, as indicated by the stern results, showing the frothy nature of the upper layer.

The aim of this work is to describe the phenomena of bubble in the financial, but especially in the real estate market; based on gained information, the current situation of Chinese real estate market is described. This work is divided into theoretical and more practical part. The theoretical part is devoted to the definition of bubble, bubbles in asset market, real estate market bubbles specifics and its causes analysis, identification and implications for the economy. Also, the Japanese real estate bubble is described. The second part describes the evolution of Chinese real estate market and provides overview of the milestones in its evolution. Moreover, it deals with specifics of the Chinese real estate market and explains the factors behind the rise in prices. Further in second part, situation on Chinese housing market is compared with the one in Japan during real estate bubble. Furthermore, this thesis explains how state government can coordinate, regulate and intervene on the market and comes up with short-term outlook.

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Human decision making process is influenced by many external as well as internal factors. Our behaviour cannot be deemed as fully rational. This thesis investigates the effect of emotional anchoring on a propensity to enter an asset bubble. This effect was observed in an experiment ran on an online crowdsourcing platform, Amazon Mechanical Turk. The negative anchor proves to have a significant negative effect, i.e. when a subject is under the negative anchor she is more prone to enter the bubble. The positive anchor does not have any significant effect. This thesis contributes to the general knowledge by confirming that trading decisions we make are subjected to the emotions we feel prior to making the decisions. JEL Classification C72, C91, D03, D53 Keywords Bubble game, anchoring, emotions Author's e-mail david.pospisil89@gmail.com Supervisor's e-mail vaclav.korbel@fsv.cuni.cz

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We present an experimental study on the behavior of bubbles captured in a Taylor vortex. The gap between a rotating inner cylinder and a stationary outer cylinder is filled with a Newtonian mineral oil. Beyond a critical rotation speed (ω[subscript c]), Taylor vortices appear in this system. Small air bubbles are introduced into the gap through a needle connected to a syringe pump. These are then captured in the cores of the vortices (core bubble) and in the outflow regions along the inner cylinder (wall bubble). The flow field is measured with a two-dimensional particle imaging velocimetry (PIV) system. The motion of the bubbles is monitored by using a high speed video camera. It has been found that, if the core bubbles are all of the same size, a bubble ring forms at the center of the vortex such that bubbles are azimuthally uniformly distributed. There is a saturation number (N[subscript s]) of bubbles in the ring, such that the addition of one more bubble leads eventually to a coalescence and a subsequent complicated evolution. Ns increases with increasing rotation speed and decreasing bubble size. For bubbles of non-uniform size, small bubbles and large bubbles in nearly the same orbit can be observed to cross due to their different circulating speeds. The wall bubbles, however, do not become uniformly distributed, but instead form short bubble-chains which might eventually evolve into large bubbles. The motion of droplets and particles in a Taylor vortex was also investigated. As with bubbles, droplets and particles align into a ring structure at low rotation speeds, but the saturation number is much smaller. Moreover, at high rotation speeds, droplets and particles exhibit a characteristic periodic oscillation in the axial, radial and tangential directions due to their inertia. In addition, experiments with non-spherical particles show that they behave rather similarly. This study provides a better understanding of particulate behavior in vortex flow structures. / Singapore-MIT Alliance (SMA)

Canada has the largest known reserve of oil in the world in the form of oil sands: an estimated 1.7 to 2.5 trillion barrels of oil are deposited in combination of the sand, water and clay. The presented research is devoted to bubble-solid surface interaction, which is one of the critical areas of the oil sand processing and it is also a key point for many other processing technologies, such as mineral recovery, froth flotation, soil remediation, de inking of paper, heat transfer in boilers tube, biological and medical sciences. The goal of this work was to investigate new theoretical and practical approaches, which would help in better understanding of fundamentals of the flotation process in oil sands extraction. Among many achievements of this research are: 1)development of the method for generation of a single micro bubble. Dependence of this process on micropipette tip size and inclination, gas type, taper length and other parameters has also been studied (Chapter 3); 2)study of gas bubble - flat surface interactions based on a practical approach of determination of two dynamic parameters, sliding velocity and induction time of a gas bubble. Various types of gas bubbles (CO2, Air, H2, and O2) and collector surfaces (bitumen, treated hydrophobic and hydrophilic silica) were used in sliding velocity and induction time measurements. The sliding velocity of gas bubbles under an inclined collector surface was found to be in a strong dependence of water chemistry, type of gases, temperature, initial separation between bubble and collector surface (Chapter 4); 3)developing an analytical model for predicting bubble sliding velocity based on previously developed models. The model was in a good agreement with experimental results (Chapter 5); 4)establishing a new method for bubble zeta potential measurements. The measurements were in a good agreement with previously studies reported in literature (Chapter 6). Summarized above findings from this research represent valuable advances in understanding oil sands processing. The prospects of future work are provided in Chapter 8. / Chemical Engineering