Heterogeneous Computing on Mixed Unstructured Grids with PyFR

PyFR is an open-source high-order accurate computational fluid dynamics solver for mixed unstructured grids that can target a range of hardware platforms from a single codebase. In this paper we demonstrate the ability of PyFR to perform high-order accurate unsteady simulations of flow on mixed unstructured grids using heterogeneous multi-node hardware. Specifically, after benchmarking single-node performance for various platforms, PyFR v0.2.2 is used to undertake simulations of unsteady flow over a circular cylinder at Reynolds number 3 900 using a mixed unstructured grid of prismatic and tetrahedral elements on a desktop workstation containing an Intel Xeon E5-2697 v2 CPU, an NVIDIA Tesla K40c GPU, and an AMD FirePro W9100 GPU. Both the performance and accuracy of PyFR are assessed. PyFR v0.2.2 is freely available under a 3-Clause New Style BSD license (see www.pyfr.org).Comment: 21 pages, 9 figures, 6 table

Out of the archaeologist's desk drawer: communicating archaeological data online

During archaeological field work a huge amount of data is collected, processed and elaborated for further studies and scientific publications. However, access and communication of linked data; associated tools for interrogation, analysis and sharing are often limited at the first stage of the archaeological research, mainly due to issues related to IPR. Information is often released months if not years after the fieldwork. Nowadays great deal of archaeological data is 'born digital' in the field or lab. This means databases, pictures and 3D models of finds and excavation contexts could be available for public communication and sharing. Researchers usually restrict access to their data to a small group of people. It follows that data sharing is not so widespread among archaeologists, and dissemination of research is still mostly based on traditional pre-digital means like scientific papers, journal articles and books. This project has implemented a web approach for sharing and communication purposes, exploiting mainly open source technologies which allow a high level of interactivity. The case study presented is the newly Mithraeum excavated in Ostia Antica archaeological site in the framework of the Ostia Marina Project

Video anomaly detection using deep generative models

Video anomaly detection faces three challenges: a) no explicit definition of abnormality; b) scarce labelled data and c) dependence on hand-crafted features. This thesis introduces novel detection systems using unsupervised generative models, which can address the first two challenges. By working directly on raw pixels, they also bypass the last

GenASiS: General Astrophysical Simulation System. I. Refinable Mesh and Nonrelativistic Hydrodynamics

GenASiS (General Astrophysical Simulation System) is a new code being developed initially and primarily, though by no means exclusively, for the simulation of core-collapse supernovae on the world's leading capability supercomputers. This paper---the first in a series---demonstrates a centrally refined coordinate patch suitable for gravitational collapse and documents methods for compressible nonrelativistic hydrodynamics. We benchmark the hydrodynamics capabilities of GenASiS against many standard test problems; the results illustrate the basic competence of our implementation, demonstrate the strengths and limitations of the HLLC relative to the HLL Riemann solver in a number of interesting cases, and provide preliminary indications of the code's ability to scale and to function with cell-by-cell fixed-mesh refinement.Comment: Belated update to version accepted ApJ

View-dependent Exploration of Massive Volumetric Models on Large Scale Light Field Displays

We report on a light-field display based virtual environment enabling multiple naked-eye users to perceive detailed multi-gigavoxel volumetric models as floating in space, responsive to their actions, and delivering different information in different areas of the workspace. Our contributions include a set of specialized interactive illustrative techniques able to provide different contextual information in different areas of the display, as well as an out-of-core CUDA based raycasting engine with a number of improvements over current GPU volume raycasters. The possibilities of the system are demonstrated by the multi-user interactive exploration of 64GVoxels datasets on a 35MPixel light field display driven by a cluster of PCs.1037-1047Pubblicat

3D RECONSTRUCTION OF ANCIENT EGYPTIAN ROCK-CUT TOMBS: THE CASE OF M.I.D.A.N.05.

Abstract. In this paper we present an on-going work to reconstruct a 3D model of M.I.D.A.N.05., an ancient Egyptian tomb located in Luxor. The reconstruction aims at producing a high quality 3D model of the tomb to help in archaeological investigation and other scientific uses. We present details about the different stages of the used reconstruction pipeline, the results so far, and the evaluation of the results in view of the project objectives