Call number: LD2668 .T4 1958 W45

Call number: LD2668 .T4 1964 D75 / Master of Science

We apply anisotropic Banach space methods together with operator renewal theory to obtain polynomial rates of decay of correlations for a class of generalized baker's transformations. The polynomial rates were proved for a smaller class of observables in a 2013 paper of Bose and Murray by fundamentally different methods. Our approach provides a direct analysis of the Frobenius-Perron operator associated to a generalized baker's transformation in contrast to the paper of Bose and Murray where decay rates are obtained for a factor map and lifted to the full map. / Graduate

Correlations and entanglement in a chain of three oscillators A,B,C with nearest neighbour coupling is studied. Oscillators A,B and B,C are coupled but there is no direct coupling between oscillators A,C. Examples with initial factorizable states are considered, and the time evolution is calculated. It is shown that the dynamics of the tri-partite system creates correlations and entanglement among the three oscillators and in particular, between oscillators A,C which are not coupled directly. We have performed photon number selective and non-selective measurements on oscillator A and we investigated their effects on the correlations and entanglement. It is shown that, before the measurement, the correlations between oscillators A,C can be stronger than the correlations of oscillators A,B. Moreover, some entanglement witness shows that oscillators A,C are entangled but the oscillators A,B might or might not be entangled. By using quantum discord, which measures the quantumness of correlations, it is shown that there are quantum correlations between oscillators A,B and after the measurements in both cases of selective and non-selective measurements, oscillators A,B and A,C become classically correlated.

No description available.

Theoretical models of information storage in the brain have suggested that neurons may undergo an experience-dependent tuning or sharpening of their representations in order to maximize the amount of information that can be stored. Changes in the tuning profiles of neurons have been demonstrated to occur when animals must learn perceptual discriminations, however, whether similar changes occur in the absence of behavioral demands is unclear. To address these questions, the activity of simultaneously recorded medial temporal lobe (MTL) neurons was studied in relation to a passive visual recognition memory task. The structure of this task was such that it allowed for a comparison between novelty related responses as well as tuning properties of individual neurons. A total of 565 well isolated single neurons were recorded. The first contribution of this dissertation is the finding of a dissociation between different medial temporal lobe regions such that neurons in temporal area F (TF), but not perirhinal cortex (PRC) or the hippocampus, show an experience-dependent change in their stimulus selectivity. This finding indicates that tuning of stimulus representations may be an effective mechanism for maximizing information storage in some brain regions. The absence of stimulus tuning in higher level association regions (i.e. TF and PRC) suggests that tuning in these regions may be disadvantageous due to the need to construct unified representations across sensory modalities. A complimentary question to the question of network storage capacity is how networks avoid saturation in the connections between neurons. The second contribution of this dissertation is the finding that there exists a decrease in the magnitude of the short time scale correlations between pairs of neurons; suggesting that networks reduce the number of connections between neurons as a stimulus becomes familiar. Gamma oscillations have been proposed to be the mechanism by which groups of neurons coordinate their activity. However, network coordination has only been indirectly measured. The final contribution of this dissertation is the finding that the magnitude of gamma oscillations is strongly correlated with enhanced magnitude of correlations between neurons.

No description available.

Frying oil is a heat and mass transfer medium, which affects the quality of food. The reaction mechanisms in deep-frying oils are mainly thermal oxidation, hydrolysis, and polymerization, which result in lipid deterioration. Addition of synthetic or natural antioxidants can effectively slow down lipid deterioration during deep-frying. Total polar components, polymerized triglycerides, p-anisidine value, acid value and iodine value are reliable indicators for assessing oil degradation during frying. Color darkening of deep-frying oils is one of apparent changes during deep-frying and is closely associated with the levels of decomposition compounds in the frying oils. However, the evidence of the relationship between color and deep-frying oil quality indicators are scanty. The main objective of this thesis is to develop a model for rapid assessment of oil quality during 30-hour deep-frying processes using oil color and quality as indicators. Significant color changes (p < 0.05) were observed in soybean oil as compared to canola and sunflower oil during 30-hour deep-frying trials. Canolol-enriched frying oils showed the highest color values before deep-frying, but the final results showed the least color changes (p < 0.05) during the 30-hour deep-frying trials. The highest percentage of total polar components (15.55 %), polymeric triglycerides (9.3 %), and p-Anisidine value (62.34) were found in TBHQ-enriched deep-frying oil samples in soybean oil. The highest acid value (3.06 mg KOH/100g) was found in canolol-enriched frying oil samples in canola oil. Rosemary and canolol-enriched deep-frying oil samples showed significant effect (p < 0.05) on color changes while reducing formation of total polar components, polymeric triglycerides, and aldehydes during the 30-hour deep-frying study. Significant correlations (p < 0.05) were found between color and oil quality indicators in all of the deep-frying oil samples; significant regression (p < 0.05) models are expressing the level of oil deterioration from color (light-dark, red-green, yellow-blue) in deep-frying oils. Overall, this study established several models using color as an indicator aiming to rapidly assess deep-frying oil quality. / October 2016

A careful review of the literature showed that there is a serious lack of information (experimental or analytical) on the pressure losses during two-phase flow in combining tee junctions. Pipe networks in industrial applications involve combining and dividing junctions and knowledge of the pressure losses at these junctions is essential for analysis of the flow distribution in the network. To this end, the pressure losses of air-water mixtures passing through a horizontal, combining tee junction with a 37.8 mm diameter were experimentally studied with annular, wavy, and slug flow regimes in the outlet. The test matrix independently varied the outlet flow rates, the outlet mixture qualities, the gas distribution between the inlets, and the liquid distribution between the inlets. All experiments were conducted at room temperature and a nominal absolute pressure at the centre of the junction of 150 kPa. The pressure distribution in all three legs of the tee was determined using up to 49 pressure taps distributed among the three sides and monitored using pressure transducers to produce accurate measurements of the pressure losses. Time-averaged pressure measurements with annular and wavy flows are reported, while pressure measurements with slug flows were not repeatable. A new model and empirical coefficients is presented that allows accurate prediction of pressure losses for flows with either an annular or wavy outlet. Time-varying pressure measurements are presented and analyzed using probability density functions. Different distributions were found for differential measurements depending on whether or not slugging was present in the system. The probability density functions for cases with annular or wavy flow in the outlet followed Gaussian distributions, while cases with slug flow had skewed distributions. Time-varying pressure signals showed a time lag between slug events based on pressure tap locations. A visual study with slug flow present in the system showed upstream travelling waves induced in a stratified inlet when slug flow was present in the other, which led to unexpected slugging under certain flow conditions. / October 2016

Philosophiae Doctor - PhD / This thesis describes research work undertaken to study neutron pairing correlations in 136Ba via the 138Ba(p, t) pair transfer reaction and to perform high-precision spectroscopy of low-lying states in 136Cs using the 138Ba(d, ) reaction. The aim of this project was to provide useful spectroscopic information relevant for matrix element calculations of 136Xe neutrinoless double beta decay. This work is relevant because neutrinoless double beta decays are standard-model-forbidden lepton number violating processes, which if observed, would establish the Majorana nature of the neutrinos and also determine the absolute mass scale of the light Majorana neutrinos. Our experiments show a signi cant fragmentation of the two-neutron transfer (p, t) strength to excited 0+ states in 136Ba, which could signi cantly affect future matrix element calculations. Additionally we obtain information on 65 new states in 136Cs observed in this work. It is anticipated that these new information will play a vital role in improving the precision of calculated matrix elements for 136Xe double beta decays.