Posts
Jan, 23
Implementing Open-Source CUDA Runtime
Graphics processing units (GPUs) are the state of the art embracing the concept of many-core technology. Their significant advantage in performance and performanceper-watt compared to traditional microprocessors has facilitated development of GPUs in many compute applications. However, GPUs are often treated as "black-box" devices due to proprietary strategies of hardware vendors. One of the greatest […]
Jan, 22
Data parallel patterns on CPU/GPU mix
We propose a model that uses a small set of quite simple parameters to devise a proper partitioning{between CPU and GPU cores{of the tasks deriving from structured data parallel patterns/algorithmic skeletons. The model takes into account both hardware related and application dependent parameters. It eventually computes the percentage of tasks to be executed on CPU […]
Jan, 22
A GPU Accelerated Navier-Stokes Solver with Multi-level Granularity for Solving Sparse Implicit Systems
In recent years, researchers have employed a wide array of multi-physics computational tools, of varying sophistication, to simulate brownout conditions [1-3]. Among these tools, compressible high-fidelity Reynolds-Averaged Navier Stokes (RANS) solvers [3] depend the least on empirical assumptions. However, the high computational expense involved in RANS simulations of viscous, rotary environments, makes it less attractive […]
Jan, 22
Accelerating Fast Fourier Transforms Using Hadoop and CUDA
There has been considerable research into improving Fast Fourier Transform (FFT) performance through parallelization and optimization for specialized hardware. However, even with those advancements, processing of very large files, over 1TB in size, still remains prohibitively slow. Analysts performing signal processing are forced to wait hours or days for results, which results in a disruption […]
Jan, 22
The PEPPHER Composition Tool: Performance-Aware Dynamic Composition of Applications for GPU-based Systems
The PEPPHER component model defines an environment for annotation of native C/C++ based components for homogeneous and heterogeneous multicore and manycore systems, including GPU and multi-GPU based systems. For the same computational functionality, captured as a component, different sequential and explicitly parallel implementation variants using various types of execution units might be provided, together with […]
Jan, 22
Analysis of Metallic Nanostructures by a Discontinuous Galerkin Time-Domain Maxwell Solver on Graphics Processing Units
In this thesis, we examine the optical properties of metallic nanostructures with typical feature sizes of the order of visible light. The interaction of light with such structures can be accurately described by classical electrodynamics. Thus, for the analysis of metallic nanostructures within this thesis, we will employ Maxwell’s equations [1] to model the physical […]
Jan, 20
Accelerating Image Reconstruction in Dual-Head PET System by GPU and Symmetry Properties
Positron emission tomography (PET) is an important imaging modality in both clinical usage and research studies. We have developed a compact high-sensitivity PET system that consisted of two large-area panel PET detector heads, which produce more than 224 million lines of response and thus request dramatic computational demands. In this work, we employed a state-of-the-art […]
Jan, 20
The Fast Multipole Method on the Cell processor
This paper presents the first deployment of the Fast Multipole Method on the Cell processor (PowerXCell 8i). We rely on the matrix formulation with BLAS routines of the FMB code (Fast Multipole with BLAS) in order to directly and efficiently offload the most time consuming operators of both far field and near field computations on […]
Jan, 20
Fast Positron Range Calculation in Heterogeneous Media for 3D PET Reconstruction
This paper presents a fast GPU-based solution to compensate positron range effects in heterogeneous media for iterative PET reconstruction. We assume a factorized approach, where projections are decomposed to phases according to the main physical effects. Positron range is the first effect in this chain, which causes a spatially varying blurring according to local material […]
Jan, 20
Parallel Distributed Face Search System for National and Border Security
The CCTV surveillance industry is undergoing a sea change due to the adoption of IP technologies. This is allowing the integration of a plethora of new cameras and other sensors into huge integrated networks. Adoption of IP technologies is presenting opportunities for scalable visual analytics that has the potential to add enormous value to entire […]
Jan, 19
Duality based optical flow algorithms with applications
We consider the popular TV-L^1 optical flow formulation, and the so-called duality based algorithm for minimizing the TV-L^1 energy. The original formulation is extended to allow for vector valued images, and minimization results are given. In addition we consider different definitions of total variation regularization, and related formulations of the optical flow problem that may […]
Jan, 18
GPU-accelererated regularisation of large diffusion-tensor volumes
We discuss the benefits, difficulties, and performance of a GPU implementation of the Chambolle-Pock algorithm for TGV (total generalised variation) denoising of medical diffusion tensor images. Whereas we have previously studied the denoising of 2D slices of $2 times 2$ and $3 times 3$ tensors, attaining satisfactory performance on a normal CPU, here we concentrate […]