Since 2002 Perimeter Institute has been recording seminars, conference talks, and public outreach events using video cameras installed in our lecture theatres. Perimeter now has 7 formal presentation spaces for its many scientific conferences, seminars, workshops and educational outreach activities, all with advanced audio-visual technical capabilities. Recordings of events in these areas are all available On-Demand from this Video Library and on Perimeter Institute Recorded Seminar Archive (PIRSA). PIRSA is a permanent, free, searchable, and citable archive of recorded seminars from relevant bodies in physics. This resource has been partially modelled after Cornell University's arXiv.org.
In the present work the motion of disc-shaped particles in a nematic liquid crystal was simulated via a Lattice Boltzmann algorithm. Under the action of a rotating magnetic field the colloidal disc with perpendicular surface anchoring immersed in a nematic liquid crystal experiences a torque and continues turning following the field. However when the disc reaches some critical position when the director field around it is highly distorted the disc suddenly flips to minimize the free energy.
One of the most challenging problems in computational galaxy formation is modeling distant heating and ionization by locally produced radiation. Most Radiative Transfer (RT) techniques are very computationally expensive and limit users to poor resolution or post-processing thus decoupling the radiation from the dynamics of the simulation. We present a new efficient method for RT implemented in the SPH code GASOLINE aimed at full cosmological simulations.
Accurate efficient and scalable computational methods are highly desirable for large-scale scientific computing applications especially for problems exhibiting spatial and temporal multi-resolution scales non-trivial geometries and complex boundary conditions (BSc). For global magnetohydrodynamics (MHD) modelling of space-physics problemshigh-performance approaches could significantly reduce the grid requirements to achieve targeted solution accuracies thereby enabling more affordable yet accurate predictions of space-plasma flows.
A low troposphere MST type radar located in Costa Rica was used to gather information up to 6 km. With the digital radar technique used thousands of sweeps can be recorded every second. Challenges in processing spectral analysis and radar imaging were addressed with tools provided by HPC.
The problem of calculation of electro and thermo static fields in an infinite homogeneous medium with a heterogeneous isolated inclusion (Kanaun et al) has shown to be reduced to the solution of integral equations for the fields inside the inclusion using Gaussian functions (V. Mazya) for the approximation of the unknown fields. Using this approach coefficients of the matrix of the discretized system will be obtained in closed analytical forms.
The effects of the microstructure of metal films on device performance and longevity have become increasingly important with the recent advances in nanotechnology. Depending on the application of the metal films and interconnects certain microscopic structures and properties are preferred over others. A common method to produce these films and interconnects is through electrodeposition. As with every process the ability to control the end product requires a detailed understanding of the system and the effect of operating conditions on the resulting product.
The goal of this research is to investigate theoretically the possibility of creating graphene-based semiconducting 2D heterosystems that allow tailoring of the band gap and creating states inside the gap by demand. Such systems are created in our computational experiment by depositing graphene on a layer of hexagonal boron nitride and adding hydrogen on top and bottom of the systems to passivate the dangling bonds and create covalent bonding between the layers of the system of interest.
Discontinuous Galerkin finite element (DGFE) methods combine advantages of both finite differences and finite elements approaches. These methods scale extremely well and they have been very successful in computational fluid dynamics. As such we would like to transpose them to the domain of relativistic astrophysics. Recently we have implemented DGFE methods in the Einstein Toolkit a large numerical relativity codebase used by hundreds of scientists around the world.
Electroencephalography (EEG) is a method for measuring brain activity by recording electrical fields at the scalp surface. Although it has the highest temporal resolution among brain imaging techniques it has low spatial resolution and is very sensitive to various forms of noise (e.g. movement artifacts electrical sources in the environment impedance artifacts and various biological artifacts typically generated from muscle activation).