Monthly Archives: May 2009

Detection, Monitoring and Damage Evaluation of Natural Disasters Based on Remote Sensing of the Earth

Teodora Canova, Milena Lazarova, Plamenka Borovska

Abstract: The paper discusses the possibilities provided by computer-based analysis of satellite based remotely sensed data of the Earth for timely registration, early warning, successful monitoring, risk assessment and consequences of various natural disasters. The state of the art sensor devices on board of the satellites orbiting the Earth are presented in view of the possibilities they offer for various natural disasters detection — wildfires, deforestation, oil spills detection, water pollution, soil pollution and salinity, etc. The methods and algorithms for solving the above stated problems are described such as spectral profiles, vegetation indices, context-based algorithms for detection of objects with certain spatial and spectral characteristics, multispectral classification. A comparative analysis are made and the data sources that can be used for solving the specified problems are justified, in terms of their spatial, spectral and temporal resolution.

Key words: remote sensing, active and passive satellite sensors, disaster monitoring

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Analysis and Estimation of Statistical Methods for Defining the Hurst Parameter of Self-Similar Processes

Evgeniya Gospodinova

Abstract: Analysis and estimation of widely used statistical methods for defining the Hurst parameter of self-similar processes in terms of defined qualitative and quantitative indexes are presented in the paper. In order to determine the quality of statistical methods in terms of the investigated parameters via experiments, a self-similar process with exact parameters has been simulated. The parameters of simulated process are: mean value, dispersion, autocorrelation function and minimum size of self-similar process. As a result, the best statistical method which can be used when defining the Hurst parameter of self-similar process has been defined.

Key words: Hurst parameter, self-similar process, fractional Gaussian noise (FGN)

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Tools for Real Time Memory’s Behaviour Characterising in Embedded Systems

Kamelia Raynova, Dragomir Tchalakov

Abstract: Enhancing performance and dependability of embedded systems, especially these for process control, depends on optimal use of the system’s memory. The use of the higher level programming languages possibilities for program debugging or the microcontroller’s embedded Build-1n Self Test (B1ST) tools do not give a direct and in-depth control over memory devices operation and in most cases cannot be carried out under real exploitations conditions. This lack may impede to discover lapses or bugs in hardware or software. The present work discusses a method and arrangement to observe, record and analyse system memory’s accesses and to estimate energy consumption of the used memory.

Keywords: embedded systems, debugging, real-time testing, FIFO

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Reversal Parser — Concept and Practical Realization

Bozhidar Georgiev

Abstract: The purpose of this research is to present the practical advantages of thus proposed
reversal parser (RP) based on standard SAX. The reversal parser (in short RP) is a two-streaming,
two-way XML parser that begins handling the input XML string from its both sides. Reversal parser starts parsing process following directions from left to right and simultaneously from right to left. Further are described the common algorithm and the basic programming modules of reversal parser. The results and analyses are shown to prove the theoretical grounds [8] in the proposed solutions. Here is built test schema with different by size and by complexity XML input documents. The acceleration of parsing mechanisms when parsing quickly and efficiently huge input string of elements becomes topical with the growth of the significance of metalanguage XML. Actually, XML is steadfast and important part in all WEB architectures (including WEB 3.0).
Key words: Extensible Markup Language (XML), Extensible Style Sheets Language (XSLT),
Simple API for XML (SAX), Wireless Markup Language (WML), Syntax Analyzer (Parser), Uniform
Resource Identifier (URI), well-formed XML, Document Type Definition (DTD), WWW Consortium
(W3C), Uniform Resource Locator (URL).

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Analyzing the Possibilities of a Standard Graphics Package for Computer Simulation and Visualization

Virginiya Dimitrova

Abstract: The article presents a comprehensive analysis of possibilities of 3ds max graphics package from the point of view of computer simulation and visualization. The first aspect is related to the analysis of the extremely powerful possibilities of 3ds max for modeling that allow creation of precise and vital 3D models both for forces and for environment influenced. The next aspect concerns the possibilities for calculation of the forces’ impact for an arbitrary set of points in the space in order to form effective simulation modules. At last, 3ds max possibilities related to “raw” data processing and different techniques for data visualization are analyzed. The presented material is illustrated using results of the developed prototype for low-frequency magnetic field simulation and visualization.

Key words: 3D modeling, computer simulation, electromagnetic analysis, materials and texturing, object-oriented programming, subdivision, visualization techniques

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A New Data Encryption Approach for Storage Area Network

Krasimir Miloshev, Stoicho Stoichev

Abstract: In this work we propose a new approach based on encrypting LUNs. In computer storage, a logical unit number or LUN is simply the number assigned to a logical volume. Logical volumes are storage entities, created over physical disks by special system tools called volume managers. With regards to the storage arrays they can span different physical disks residing on different enclosures. We are exposing a new method of encryption, based on encrypting those LUNs.

Keywords: SAN, encryption, MST, Graph Algorithms, LUN

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Schedulability of Real-Time Messages in Heterogeneous Type Networks — CAN/Ethernet

Ivan Evgeniev

Abstract: This paper discusses some problems about scheduling heterogeneous Ethernet/CAN real-time networks. Modification of standard Ethernet-based communication subsystem to token-ring and integrated communication system providing media independent transmission process are proposed. Analyzes of protocol structure, concurrences, possible race conditions and methods for their suppressing are parts of presented research. Structure and operation of a network bridge connecting branches based on different media is discussed in the paper. Finally, some measurements of execution times of implemented communication elements for Windows CE are presented too.

Keywords: real-time networks, heterogeneous network, CAN, real-time Ethernet.

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FPGA-based Architectures for Digital Image Processing and Visualization

Iva Nikolova, Hristo Nikolov, Peter Manoilov, Georgi Zapryanov

Abstract: Field Programmable Gate Array (FPGA) technology has become a viable target for the implementation of algorithms suited to image processing applications. The unique architecture of the FPGA has allowed the technology to be used in many such applications encompassing all aspects of image processing and visualization. The main focus of this paper is to present a logic design and FPGA-based hardware implementation of high-performance edge-detection architecture for real-time image processing applications and device for control for displaying digital images.

Key words: Image Processing, Displays, FPGA

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Architectural Aspects of the Most Powerful Modern Supercomputers

Plamenka Borovska, Desislava Ivanova, Dragi Kimovski, Bzar Khidir

Abstract: In today’s word supercomputers are the main tool that gives push to science to reach new frontiers. That is why the development and evolution of these machines is very important. Starting from the beginning of this century, supercomputing science was boasted and become very popular and important. The goal of this paper is to give essential information for the fastest supercomputers according to the TOP500 list and to describe the main architectural aspects, including internal topologies and interconnection networks.

Key words: Supercomputer architectures, interconnect networks, topologies, supercomputer performance, supercomputer evolution

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Enabling High Level Security in Mobile Computers Equipped with Trusted Platform Module

Elior Vila

Abstract: Trusted Computing (TC) is well known and widely distributed especially to mobile
computers equipped with a hardware-based component called Trusted Platform Module (TPM).
TPM provides security functions which can be utilized to protect valuable information and ensure secure computing environment. The main goal of this paper is to provide solid improved
approaches towards utilization of protection capabilities of TPM with respect to the encryption and decryption of data and also to the protection of authorization credentials. Important criteria such as enabling high level of security, user control, convenience, and easy implementation are primarily taken into consideration. The proposed approaches are based on some modifications of the current available approaches as well as on addition of new functions which facilitate the TPM use in practical scenarios.
Keywords: encryption/decryption, hardware-based security, trusted computing, trusted platform module.

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