Detailed Analysis of Structures in the Foot Wall of the Champlain Thrust at Lone Rock Point, Burlington, Vermont

The objective of this project was to identify a strain gradient and relative chronology within the foot wall of the Champlain Thrust Fault at Lone Rock Point, Burlington, Vermont in order to determine how the unique fault-bounded ellipsoidal lozenge structures formed and why they are contained to one area within the foot wall. Previously researched models seemed to suggest the fault bounded lozenges were a horse thrust system that followed the strong pre-existing limestone/dolostone bedding layers of the Iberville Shale. However, this paper indicates that the lozenges are a horse thrust system formed by an S-C fabric between the 1st and 2nd generation cleavages, not by bedding, and as such are a gauge of moderate strain within the foot wall. Also, by identifying a relative chronology within the foot wall, this paper lays the groundwork to explain why two wells drilled near Lone Rock Point by McGill University in the summer of 2014 observed the Champlain Thrust Fault to have a thirty five meter depth difference over a ten meter distance. The original hypothesis to explain this observation was that normal faults were crosscutting the main thrust and causing the displacement. However, this paper failed to conclusively support that hypothesis since the normal faults identified within the foot wall were found to neither cross the main thrust nor displace rock more than one centimeter. Further research should be conducted within the hanging wall at Lone Rock Point to conclusively interpret this observation

Complex Imaging with Ray-rotating Windows

We study the imaging properties of windows that rotate the direction of transmitted light rays by a fixed angle around the window normal [A. C. Hamilton et al., J. Opt. A: Pure Appl. Opt. 11,085705 (2009)]. We previously found that such windows image between object and image positions with suitably defined complex longitudinal coordinates [J. Courtial et al., Opt. Lett. 37, 701 (2012)]. Here we extend this work to object and image positions in which any coordinate can be complex. This is possible by generalising our definition of what it means for alight ray to pass through a complex position: the vector from the real part of the position to the point on the ray that is closest to that real part of the position must equal the cross product of the imaginary part of the image position and the normalised light-ray-direction vector. In the paraxial limit, we derive the equivalent of the lens equation for planar and spherical ray-rotating windows. These results allow us to describe complex imaging in more general situations, involving combinations of lenses and inclined ray-rotating windows. We illustrate our results with ray-tracing simulations

Development of 3D Sculpted, Hyper-Realistic Biomimetic Eyes for Humanoid Robots and Medical Ocular Prostheses

Abstract. Hyper-realistic Humanoid Bio-robotic Systems (HHBS) are the precise electro-mechanical bodily emulation of natural human being in materiality, form and function. However, the standardised approach of constructing static ocular prosthesis for implementation in modern HHBS design, contradicts innate organic human criterion as the artificial eyes are void of the intricate dynamic fluidic functions of the natural human iris. The aim of this paper is to outline the development and construction process of a pair of realistic artificial humanistic optical retinal sensors that accurately simulate the autonomous fluctuating operations of the human iris in reaction to visceral emotion and photo-luminescent stimuli and retain the optical sensory capability and integral aesthetic materialism of the organic eye. The objective of the auto-dynamic pupillary framework is to advance the external expressive / embodied realism of HHBS towards achieving a more accurate operational and embodied simulation. Prospective future application and advancement of the outlined optical system presents potential implementation in the field of medical ocular prosthetic design, with the aim of enhancing the naturalistic operations of future fabricated human eye replicas, thus conceivably reducing the malaise and discomfiture commonly associated with the archetypical fixed artificial eyes

Numerical evaluation and robustness of the quantum mean force Gibbs state

Funding: Y.F.C. acknowledges funding from the St Andrews Undergraduate Research Assistant Scheme, the School of Physics and Astronomy Student-Staff Council vacation awards, and the University of St Andrews Physics Trust. J.K. acknowledges funding from EPSRC (EP/T014032/1).We introduce a numerical method to determine the Hamiltonian of Mean Force (HMF) Gibbs state for a quantum system strongly coupled to a reservoir. The method adapts the Time Evolving Matrix Product Operator (TEMPO) algorithm to imaginary time propagation. By comparing the real-time and imaginary-time propagation for a generalized spin-boson model, we confirm that the HMF Gibbs state correctly predicts the steady state. We show that the numerical dynamics match the polaron master equation at strong coupling. We illustrate the potential of the imaginary-time TEMPO approach by exploring reservoir-induced entanglement between qubits.PostprintPeer reviewe

Efficient real-time path integrals for non-Markovian spin-boson models

Funders: Strathearn - EPSRC, ID: EP/L505079/1, Lovett - EPSRC, ID: EP/K025562/1, Kirton- EPSRC, ID: EP/M010910/1Strong coupling between a system and its environment leads to the emergence of non-Markovian dynamics, which cannot be described by a time-local master equation. One way to capture such dynamics is to use numerical real-time path integrals, where assuming a finite bath memory time enables manageable simulation scaling. However, by comparing to the exactly soluble independent boson model, we show that the presence of transient negative decay rates in the exact dynamics can result in simulations with unphysical exponential growth of density matrix elements when the finite memory approximation is used. We therefore reformulate this approximation in such a way that the exact dynamics are reproduced identically and then apply our new method to the spin-boson model with superohmic environmental coupling, commonly used to model phonon environments, but which cannot be solved exactly. Our new method allows us to easily access parameter regimes where we find revivals in population dynamics which are due to non-Markovian backflow of information from the bath to the system.Publisher PDFPeer reviewe

Artificial Eyes with Emotion and Light Responsive Pupils for Realistic Humanoid Robots

This study employs a novel 3D engineered robotic eye system with dielectric elastomer actuator (DEA) pupils and a 3D sculpted and colourised gelatin iris membrane to replicate the appearance and materiality of the human eye. A camera system for facial expression analysis (FEA) was installed in the left eye, and a photo-resistor for measuring light frequencies in the right. Unlike previous prototypes, this configuration permits the robotic eyes to respond to both light and emotion proximal to a human eye. A series of experiments were undertaken using a pupil tracking headset to monitor test subjects when observing positive and negative video stimuli. A second test measured pupil dilation ranges to high and low light frequencies using a high-powered artificial light. This data was converted into a series of algorithms for servomotor triangulation to control the photosensitive and emotive pupil dilation sequences. The robotic eyes were evaluated against the pupillometric data and video feeds of the human eyes to determine operational accuracy. Finally, the dilating robotic eye system was installed in a realistic humanoid robot (RHR) and comparatively evaluated in a human-robot interaction (HRI) experiment. The results of this study show that the robotic eyes can emulate the average pupil reflex of the human eye under typical light conditions and to positive and negative emotive stimuli. However, the results of the HRI experiment indicate that replicating natural eye contact behaviour was more significant than emulating pupil dilation