Lo Ka Fai / Thesis (M.Phil.)--Chinese University of Hong Kong, 1999. / Includes bibliographical references (leaves [67]-68). / Text in English; abstracts in English and Chinese. / Lo Ka Fai / Abstract --- p.ii / Acknowledgements --- p.iii / List of Figures --- p.v / List of Tables --- p.ix / Chapter 1 --- Introduction --- p.1 / Chapter 2 --- The First Problem: Heat Transfer and Large-scale Flow --- p.7 / Chapter 2.1 --- Circulating flow --- p.8 / Chapter 2.2 --- Shear flow --- p.10 / Chapter 3 --- Results and Discussions --- p.13 / Chapter 3.1 --- Circulating flow --- p.13 / Chapter 3.2 --- Shear flow --- p.17 / Chapter 4 --- The second problem: Intermittency --- p.22 / Chapter 5 --- Method of Analysis --- p.25 / Chapter 6 --- Results and discussions --- p.29 / Chapter 6.1 --- C=0.01 --- p.29 / Chapter 6.2 --- "C=0.05, 0.1 and 0.5" --- p.41 / Chapter 7 --- Conclusions --- p.60 / Chapter A --- Linear Scaling Exponents --- p.62 / Chapter B --- The Formula of and the Hierarchy --- p.64 / Bibliography --- p.66

by Pang Cheuk Sum. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1998. / Text in English; abstract also in Chinese. / by Pang Cheuk Sum. / Contents --- p.i / List of Figures --- p.iii / List of Tables --- p.v / Abstract --- p.vi / Acknowledgement --- p.viii / Chapter 1 --- Introduction --- p.1 / Chapter 2 --- The Problem --- p.7 / Chapter 2.1 --- Model of random advection --- p.7 / Chapter 2.2 --- Model without large scale flow --- p.8 / Chapter 2.3 --- "Model with, large-scale mean circulating flow" --- p.11 / Chapter 3 --- Reviews of the previous studies --- p.16 / Chapter 3.1 --- Review of previous studies on one-point scalar statistics --- p.16 / Chapter 3.2 --- Review of previous study on scalar difference --- p.18 / Chapter 4 --- Effects of a large-scale flow on one-point statistics --- p.20 / Chapter 4.1 --- Effects on mean scalar profile --- p.20 / Chapter 4.2 --- Effects on rms fluctuation --- p.23 / Chapter 4.3 --- Effects on probability density function --- p.26 / Chapter 5 --- Study of scalar difference --- p.34 / Chapter 5.1 --- Scalar difference at the center of lattice --- p.34 / Chapter 5.1.1 --- Probability density function --- p.34 / Chapter 5.1.2 --- Structure function --- p.43 / Chapter 5.1.3 --- Conditional averages --- p.52 / Chapter 5.1.4 --- Structure function at other position --- p.55 / Chapter 5.2 --- Effects of large-scale flow --- p.57 / Chapter 6 --- Summary --- p.65 / Chapter 6.1 --- Effects of a large-scale flow on passive scalar --- p.65 / Chapter 6.2 --- Statistics of scalar difference --- p.66 / Chapter A --- Simulation parameters --- p.67 / Chapter B --- Normalization of Probability Density Function --- p.68 / Bibliography --- p.69

No description available.

Zhou Quan = 关於热湍流中标量场混合和自组织结构的实验研究 / 周全. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (leaves 89-94). / Text in English; abstracts in English and Chinese. / Zhou Quan = Guan yu re tuan liu zhong biao liang chang hun he he zi zu zhi jie gou de shi yan yan jiu / Zhou Quan. / Abstract --- p.ii / Acknowledge --- p.iii / Table of Contents --- p.v / List of Figures --- p.xii / List of Tables --- p.xiii / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Rayleigh-Benard System --- p.2 / Chapter 1.1.1 --- Physics Picture --- p.2 / Chapter 1.1.2 --- Basic Equations and Characteristic Parameters --- p.3 / Chapter 1.2 --- Passive and Active Scalars --- p.6 / Chapter 1.3 --- Large-Scale Circulation (LSC) --- p.7 / Chapter 2 --- Passive and Active Scalars in Convective Thermal Turbulence --- p.9 / Chapter 2.1 --- Experimental Setup and Measurement Techniques --- p.9 / Chapter 2.1.1 --- Rectangular Cell --- p.9 / Chapter 2.1.2 --- Temperature probe: thermistor --- p.12 / Chapter 2.1.3 --- Laser Induced Fluorescence (LIF) --- p.16 / Chapter 2.2 --- Passive Scalar Measurements --- p.24 / Chapter 2.2.1 --- Concentration Time Series --- p.24 / Chapter 2.2.2 --- Statistical Properties --- p.26 / Chapter 2.3 --- Active Scalar Measurements --- p.35 / Chapter 2.4 --- Relationship between passive scalar and active scalar --- p.41 / Chapter 2.4.1 --- Cross-correlation Functions --- p.41 / Chapter 2.4.2 --- Structure Functions --- p.48 / Chapter 2.5 --- Summary --- p.60 / Chapter 3 --- The Azimuthal Motion of the Mean Wind in Turbulent Rayleigh- Benard Convection --- p.63 / Chapter 3.1 --- Experimental Setup and Measurement Techniques --- p.64 / Chapter 3.1.1 --- Cylindrical Cell --- p.64 / Chapter 3.1.2 --- Particle Image Velocimetry (PIV) --- p.65 / Chapter 3.2 --- Azimuthal Motion of the Mean Wind in the Γ = 1.0 Cell --- p.68 / Chapter 3.2.1 --- Time-trace of the LSC orientation Φ --- p.69 / Chapter 3.2.2 --- Statistical properties of azimuthal motion of the mean wind --- p.73 / Chapter 3.3 --- Azimuthal Motion of the Mean Wind in theΓ = 0.5 Cell --- p.77 / Chapter 3.3.1 --- Time-trace of the LSC orientation Φ --- p.78 / Chapter 3.3.2 --- Statistical properties of azimuthal motion of the mean wind --- p.80 / Chapter 3.4 --- Summary --- p.85 / Chapter 4 --- Conclusion --- p.86 / Chapter 4.1 --- Scalar Mixing --- p.86 / Chapter 4.2 --- The Azimuthal Motion of the LSC --- p.87 / Chapter 4.3 --- Perspective for Further Investigation --- p.88 / Bibliography --- p.88

In the construction of Canonical Loop Quantum Gravity, General Relativity is rewritten in terms of the Ashtekar variables to simplify its quantisation. They consist of a densitised triad and a connection terms. The latter depends by definition and by construction on a free parameter β, called the Barbero–Immirzi parameter. This freedom is passed on to the quantum theory as it appears in the expressions of certain operators. Their discreet spectra depend on the arbitrary value of this parameter β, meaning that the scale of those spectra is not uniquely defined. To get around this ambiguity, we propose to consider a theory of Conformal Loop Quantum Gravity, by imposing a local conformal symmetry through the addition of a scalar field. We construct our theory starting from the usual Einstein–Hilbert action for General Relativity to which we add the action for the massless scalar field and rewrite it in terms of a new set of Ashtekar-like variables. They are constructed through a set of canonical transformations, which allow to move the Barbero–Immirzi parameter from the connection to the scalar variable. We then show that the theory can be quantised by fulfilling the conditions for a Dirac quantisation. Finally, we present some first elements of the quantum formalism. It is expected that with such a scalar-tensor theory, the quantum operators should not depend on the free parameter directly but rather on the dynamical scalar field, solving therefore the ambiguity.

Downloading information from the Internet is an incredibly popular activity. Some of the information is used for scholarly or educational purposes, some is used for entertainment, as well as all sorts of other purposes. Books, movies, video games, and music are being downloaded by an increasing number of Internet users. Some of these digital files contain information that is perfectly legal to use and share but a great majority of these files are illegal to download. Recent technological developments in digital and Internet technologies have made the downloading of both legal and illegal digital content very easy and very fast. These technological developments have brought about a tension between two conflicting interests among Internet users. One of these interests drives people to download content illegally and the other interest drives people to act in ways intended to stop such illegal downloading. Much legal attention has been given to this issue in the past few years, but little sustained philosophical attention. In this thesis I discuss the moral issues that come along with the illegal downloading of information via the Internet with a focus on music files. I present the issue of illegal music downloading through the use of a scalar utilitarian theory with a focus on preference satisfaction. I conclude that the act of downloading is in aggregate morally permissible, and further, that the status quo bundle of intellectual property rights (copyright) that protect these files should be removed. Also, I provide a rough sketch of how all people concerned can satisfy both of the conflicting interests (mentioned above) through the use of copyleft protections.

<p>In general relativity, the Riemannian Penrose inequality (RPI) provides a lower bound for the ADM mass of an asymptotically flat manifold of nonnegative scalar curvature in terms of the area of the outermost minimal surface, if one exists. In physical terms, an equivalent statement is that the total mass of an asymptotically flat spacetime admitting a time-symmetric spacelike slice is at least the mass of any black holes that are present, assuming nonnegative energy density. The main goal of this thesis is to deduce geometric lower bounds for the ADM mass of manifolds to which neither the RPI nor the famous positive mass theorem (PMT) apply. This is the case, for instance, for manifolds that contain metric singularities or have boundary components that are not minimal surfaces.</p> <p>The fundamental technique is the use of conformal deformations of a given Riemannian metric to arrive at a new Riemannian manifold to which either the PMT or RPI applies. Along the way we are led to consider the geometry of certain types non-smooth metrics. We prove a result regarding the local structure of area-minimizing hypersurfaces with respect such metrics using geometric measure theory.</p> <p>One application is to the theory of ``zero area singularities,'' a type of singularity that generalizes the degenerate behavior of the Schwarzschild metric of negative mass. Another application deals with constructing and understanding some new invariants of the harmonic conformal class of an asymptotically flat metric.</p> / Dissertation

No description available.

Study of passive dispersion of a neutral scalar in turbulentflows is highly important due to its numerous applications in the areas of turbulent flow visualization, turbulent heat transfer and transport of pollutants and other substances in the environment. Over the past few decades, many analytical, numerical, and experimental studies have been conducted on this topic to obtain a better understanding of the physical process. In the present work, Large Eddy Simulations (LES) of scalar dispersion in turbulent flow over smooth and rough channels is conducted to contribute to the further understanding of the relation between the turbulent velocity field and the concentration field. The LES results from the present work showed good agreement with a recently com-pleted experimental study(Rahman and Webster [2005]). An in-depth comparison of in-stantaneous concentration and velocity fields revealed thecorrelation between scalar dis-persion and coherent structures of the turbulent flow. Also,a three dimensional visual-ization of concentration iso-surfaces at different instants provided a good picture of the concentration structures transported as a result of hairpin vortices of turbulent flow, which is quite difficult to accomplish using experimental studies.

Thesis (Ph. D.)--York University, 2000. Graduate Programme in Physics. / Typescript. Includes bibliographical references (leaves 100-105). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://wwwlib.umi.com/cr/yorku/fullcit?pNQ59128