Computer Science Journal (AGH University of Science and Technology, Krakow)
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COMPETITIVE APPROACH TO INFORMATION SYSTEM RISK ANALYSES
Get PDFThis article presents the method of IT risk assessment from human behaviour perspective, developed by the author. It is an alternative for the commonly used approaches to risk assessment, based on vulnerability and threat identification and the probability estimation of their occurrence. The authors method applies to risk calculation factors such as administrators or users skills, attackers knowledge and determination, or attack method used. The key element of the proposed risk analysis competitive method is a mathematical formula which allows for risk level quantification
ACCELERATING SELECT WHERE AND SELECT JOIN QUERIES ON A GPU
Get PDFThis paper presents implementations of a few selected SQL operations using theCUDA programming framework on the GPU platform. Nowadays, the GPU’sparallel architectures give a high speed-up on certain problems. Therefore, thenumber of non-graphical problems that can be run and sped-up on the GPUstill increases. Especially, there has been a lot of research in data mining onGPUs. In many cases it proves the advantage of offloading processing fromthe CPU to the GPU. At the beginning of our project we chose the set ofSELECT WHERE and SELECT JOIN instructions as the most common op-erations used in databases. We parallelized these SQL operations using threemain mechanisms in CUDA: thread group hierarchy, shared memories, andbarrier synchronization. Our results show that the implemented highly parallelSELECT WHERE and SELECT JOIN operations on the GPU platform canbe significantly faster than the sequential one in a database system run on theCPU
Evolutionary Multi-Agent Computing in Inverse Problems
Get PDFThe paper tackles the application of evolutionary multi-agent computing to solving inverse problems. High costs of fitness function call become a major difficulty when approachingthese problems with population-based heuristics, however evolutionary agent-based systems (EMAS)turn out to reduce the fitness function calls, which makes them a possible weapon of choicefor them. The paper recalls the basics of EMAS and describes the considered problem (Step and Flash Imprint Lithography),later showing convincing results, that EMAS turns out to be more effective than classical evolutionary algorithm
Parallelized Algorithms for Finding Similar Images and Object Recognition
Get PDFThe paper addresses the issue of searching for similar images and objects ina repository of information. The contained images are annotated with the helpof the sparse descriptors. In the presented research, different color and edgehistogram descriptors were used. To measure similarities among images, variouscolor descriptors are compared. For this purpose different distance measureswere employed. In order to decrease execution time, several code optimizationand parallelization methods are proposed. Results of these experiments, as wellas discussion of the advantages and limitations of different combinations ofmethods are presented
GRAPH GRAMMAR BASED PETRI NET CONTROLLED DIRECT SOLVER ALGORITHM
Get PDFIn this paper we present the Petri net setting the optimal order of elimination for directsolver working with hp refined finite finite element meshes. The computational mesh is representedby a graph, with graph vertices corresponding to finite element nodes. The directsolver algorithm is expressed as a sequence of graph grammar productions, attributing thegraph vertices. The Petri net dictates the order of graph grammar productions, representingthe execution of the solver algorithm over a graph representation of computational mesh.The presentation is concluded with numerical experiments performed for a model L-shapedomain
USING STANDARD HARDWARE ACCELERATORS TO DECREASE COMPUTATION TIMES IN SCIENTIFIC APPLICATIONS
Get PDFNowadays, general-purpose processors are being used in scientific computing. However, whenhigh computational throughput is needed, it’s worth to think it over if dedicated hardwaresolutions would be more efficient, either in terms of performance (or performance to price ratio),or in terms of power efficiency, or both. This paper describes them briefly and comparesto contemporary general-purpose processors’ architecture
COMPUTATION ACCELERATION ON SGI RASC: FPGA BASED RECONFIGURABLE COMPUTING HARDWARE
Get PDFIn this paper a novel method of computation using FPGA technology is presented. In severalcases this method provides a calculations speedup with respect to the General PurposeProcessors (GPP). The main concept of this approach is based on such a design of computinghardware architecture to fit algorithm dataflow and best utilize well known computingtechniques as pipelining and parallelism. Configurable hardware is used as a implementationplatform for custom designed hardware. Paper will present implementation results ofalgorithms those are used in such areas as cryptography, data analysis and scientific computation.The other promising areas of new technology utilization will also be mentioned,bioinformatics for instance. Mentioned algorithms were designed, tested and implemented onSGI RASC platform. RASC module is a part of Cyfronet’s SGI Altix 4700 SMP system. Wewill also present RASC modern architecture. In principle it consists of FPGA chips and veryfast, 128-bit wide local memory. Design tools avaliable for designers will also be presented
REAL-TIME IMPLEMENTATION OF MOVING OBJECT DETECTION IN VIDEO SURVEILLANCE SYSTEMS USING FPGA
Get PDFThe article presents the concept of real-time implementation computing tasks in videosurveillance systems. A pipeline implementation of a multimodal background generationalgorithm for colour video stream and a moving objects segmentation based on brightness,colour and textural information in reconfigurable resources of FPGA device is described.System architecture, resource usage and segmentation results are presented
Large-scale Research on Quality of Experience (QoE) Algorithms
Get PDFThe large variety of video data sources means variability not only in terms ofincluded content, but also in terms of quality. Therefore, quality assessment pro-vides an additional dimension. The paper describes a comprehensive evaluationexperiment on perceived video quality. Consequently, in summary, 19 200 000video frames will be processed. Given the scale of the experiment, it is setup on a computer cluster in order to accelerate the calculations significantly.This work on Quality of Experience (QoE) is synchronized with that conductedby the Video Quality Experts Group (VQEG), in particular the Joint EffortsGroup (JEG) – Hybrid group project