On the basic equations for the second-order modeling of compressible turbulence

Equations for the mean and turbulent quantities for compressible turbulent flows are derived. Both the conventional Reynolds average and the mass-weighted, Favre average were employed to decompose the flow variable into a mean and a turbulent quality. These equations are to be used later in developing second order Reynolds stress models for high speed compressible flows. A few recent advances in modeling some of the terms in the equations due to compressibility effects are also summarized

On the Basic Equations for the Second-order Modeling of Compressible Turbulence

Equations for the mean and the turbulence quantities of compressible turbulent flows are derived in this report. Both the conventional Reynolds average and the mass-weighted Favre average were employed to decompose the flow variable into mean and turbulent quantities. These equations are to be used later in developing second-order Reynolds stress models for high-speed compressible flows. A few recent advances in modeling some of the terms in the equation due to compressibility effects are also summarized

"Airy Children of Our Brain": Emotion, Science and the Legacy of Eighteenth-Century Philosophy in the Shelley Circle, 1812-1821

This thesis examines the physical effects of human emotion and the mind through selected texts written by the Shelley circle, including P. B. Shelley, Mary Shelley, and Lord Byron. Emotion is a significant variable that dominates human existence. For this reason, the concept of emotion continues to intrigue numerous scientists working today in the fields of neuroscience, psychology, biology, and even robotics. With the rise of neuroscientific or cognitive approaches, the materiality of the mind has also been increasingly discussed in literary studies. Critics, including Alan Richardson, Noel Jackson, and Richard Holmes, revisit the mind and English Romanticism drawing on various scientific perspectives. Other critics, such as Adela Pinch, Thomas Pfau, and Richard C. Sha, have also reflected on emotional studies and Romanticism. Finding affinities with this kind of approach, recently defined as ‘cognitive historicism’, my thesis explores the legacy of eighteenth-century mental philosophy and science in the Shelley circle, 1812-1821. I argue that the Shelley circle’s scientific understanding of the mind and emotion is influenced by the materialism, empiricism, and aesthetics prevalent in the eighteenth century, which come into their own in the Romantic period to prefigure our current scientific understanding of emotion. Chapter One surveys the Shelley circle’s preoccupation with emotion and science and how this is manifest, to varying degrees, in a wide range of critical responses to Frankenstein and writings of other members of the group during this period. During the course of this critical survey I develop the concept of the ‘materiality of emotion’, which is used in subsequent chapters to re-examine the Shelley circle’s scientific philosophy and how it is represented in literary texts written by the group. Chapter Two argues that Shelley develops his views of the mind through his atheistic and materialist reasoning. This materialist thinking of the mind in Queen Mab exerts a seminal influence on how the Shelley circle thought about the workings of human emotion. Chapter Three focuses on Mary Shelley and contemporary eighteenth- and nineteenth-century scientific debates to suggest that the representation of the mechanism of the body in Frankenstein points to the intricate relations between the mechanisms of the mind and emotion and offers a means to heal the schism between French materialism and vitalism. Chapter Four investigates the depiction of emotional effects on the mind in Byron’s Manfred and Shelley’s Alastor. Both poets draw on scientific reasoning and imagination to come to terms with grief, the failure of love, and the loss of ideals. Chapter Five claims that Shelley’s Frankenstein meditates on the effects of physiological elements of the beautiful and the ugly, as well as emotional responses to the sublime science. My final chapter draws on cultural history and gender theory to interpret Byron’s Don Juan (Canto One) and Shelley’s Epipsychidion in an attempt to reaffirm the beautiful and the sublime in their materialist concept of love or sexuality

New high-efficiency source of photon pairs for engineering quantum entanglement

We have constructed an efficient source of photon pairs using a waveguide-type nonlinear device and performed a two-photon interference experiment with an unbalanced Michelson interferometer. Parametric down-converted photons from the nonlinear device are detected by two detectors located at the output ports of the interferometer. Because the interferometer is constructed with two optical paths of different length, photons from the shorter path arrive at the detector earlier than those from the longer path. We find that the difference of arrival time and the time window of the coincidence counter are important parameters which determine the boundary between the classical and quantum regime. When the time window of the coincidence counter is smaller than the arrival time difference, fringes of high visibility (80$\pm$ 10%) were observed. This result is only explained by quantum theory and is clear evidence for quantum entanglement of the interferometer's optical paths.Comment: 4 pages, 4 figures, IQEC200

Induced Coherence and Stable Soliton Spiraling

We develop a theory of soliton spiraling in a bulk nonlinear medium and reveal a new physical mechanism: periodic power exchange via induced coherence, which can lead to stable spiraling and the formation of dynamical two-soliton states. Our theory not only explains earlier observations, but provides a number of predictions which are also verified experimentally. Finally, we show theoretically and experimentally that soliton spiraling can be controled by the degree of mutual initial coherence.Comment: 4 pages, 5 figure

A multiple-scale turbulence model for incompressible flow

A multiple-scale eddy viscosity model is described. This model splits the energy spectrum into a high wave number regime and a low wave number regime. Dividing the energy spectrum into multiple regimes simplistically emulates the cascade of energy through the turbulence spectrum. The constraints on the model coefficients are determined by examining decaying turbulence and homogeneous turbulence. A direct link between the partitioned energies and the energy transfer process is established through the coefficients. This new model was calibrated and tested for boundary-free turbulent shear flows. Calculations of mean and turbulent properties show good agreement with experimental data for two mixing layers, a plane jet and a round jet

Time-bin entangled photon holes

The general concept of entangled photon holes is based on a correlated absence of photon pairs in an otherwise constant optical background. Here we consider the specialized case when this background is confined to two well-defined time bins, which allows the formation of time-bin entangled photon holes. We show that when the typical coherent state background is replaced by a true single-photon (Fock state) background, the basic time-bin entangled photon-hole state becomes equivalent to one of the time-bin entangled photon-pair states. We experimentally demonstrate these ideas using a parametric down-conversion photon-pair source, linear optics, and post-selection to violate a Bell inequality with time-bin entangled photon holes.Comment: 6 pages, 5 figure