Monthly Archives: November 2014

Technological Considerations and Scenarios for Next Generation Access Networks

Pavlina Koleva

Abstract: Next Generation Access (NGA) networks are considered as an essential element in ensuring fast broadband (> 30Mbit/s) and ultra-fast broadband (> 100Mbit/s) access for the provision of services with increased performance, improved quality of service and symmetry of speeds. This paper focuses on the future implementation of NGA – the potential technologies to deliver NGA and specifically the technology selection considerations. The focus is on the evolvement of passive optical networks and some of the development scenarios. The perspectives of future wireless technologies for NGA are also considered.

Keywords: Fiber to the Cabinet, Fiber to the Premises, LTE Advanced, Next Generation Access, Passive Optical Networks.

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Simplified Method for Complex Evaluation of Information Systems

Aleksandar Tsenov, Mario Ivanov

Abstract: In this work, a comprehensive method for complex evaluation of IT – systems, is proposed. The systems are characterizing through great amount of estimation indicators. These are dynamic systems, which require the usage of methods to evaluate the relationships between these indicators as well. The validation of the proposed method and proving its applicability where provided on two different systems — a CRM system for a social network and IT — project evaluation system.

Key words: Information Technology, multi criteria evaluation, fuzzy logic

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GUI for Medical Image Processing on the Base of Morphological Operators

Veska Georgieva

Abstract: In the paper is presented software for morphological processing of medical images and its graphic user interface (GUI). It works in the MATLAB environment and uses IMAGE TOOLBOXES defined functions. Different morphological operators and types of structuring elements with different sizes can be used, regarding to process different medical modalities of the images. The software can realize repeatedly a nonlinear filtration, by using the same operation. The GUI proposes also an interactive option to choose the type of the morphological operation, the type of the structuring element and also its parameters. The proposed GUI can be applied to real medical images attempt to make diagnostic more precise. The presented GUI is suitable also to engineering education for studying of this processing.

Key words: Morphological operators, medical images, MATLAB environment, graphic user interface

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Facial Landmarks Detection Using Linear Regression and SIFT

Martin Penev, Ognian Boumbarov

Abstract: Accurate detection of facial components is an important operation which reflects numerous applications based on face analysis. Hence, there is a great demand on real-time algorithms for detection of face components. In this paper we propose a fast method with relatively low computational complexity, which achieves excellent results, comparable to those of the state-of-the-art methods.

Keywords: Facial Landmark Extraction, Facial Features, SIFT, Linear Regression

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An SSH-based Software Application for Remote Access Control

Nikolay Krastanov, Ivaylo Atanasov

Abstract: The paper presents a prototype of a software application for secure access control. The application provides functionality for secure access to remote resources automating the processes required for secure connection establishment. It is implemented using Java as programming language and Eclipse as integrated Development Environment, and is based on Secure Shell (SSH) as a protocol for secure communication. A key exchange protocol for SSH, based on Boneh-Franklin Identity Based Encryption is proposed. Results from application functional test are presented.

Key words: Client server architecture, authentication, encryption, key management

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3D Multi-View Reconstruction Algorithms

Mirosfav Galabov

Abstract: This article presents a several multi-view stereo reconstruction algorithms and discuss the topic of how to derive a multi-view 3D content from a stereo image pair, as the future glass-free displays require multi-view content.

Keywords: 3D content, autostereoscopic displays, multi-view reconstruction algorithm.

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Performance of RSA Algorithm Using Chinese Reminder Theorem

Ognian Nakov, Daniela Gotseva, Bulbul Zuliamova

Abstract: E-business security is an overarching business issues that, based of an analyzed risks, and establishes the threat acceptance and reduction parameters for the safe use of technology. As an overarching issue, e-business security can be thought of as being absolutely fundamental to the effective and efficient use of Information Technology in support of e-business. This paper investigated RSA-CRT algorithm for decryption of data and encryption using Chinese Remainder Theorem (CRT) for the data security. The algorithm is implemented in C# source code.

Key words: RSA Algorithm, RSA-CRT, C#, Encryption, Decryption

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Temporal Databases – Conception and Realization

Dimitar Pilev, Aneta Georgieva

Abstract: The article analyzes some temporal database models, differing in the way of setting the time in the relation, a way of data timestamping and the kind of the time – valid time and transaction time. Advantages and disadvantages of the models are analyzed. Opportunities and problems in some of the commercial implementations of temporal database management systems are discussed.

Key words: temporal databases, valid time, transaction time, temporal database models.

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Chemotherapy in Soft Matter

Irina Trifonova, Galina Kurteva

Abstract: Geometrical and thermodynamic tumor state in soft matter and the chemotherapy intensity in soft matter are defined, according to proliferation index, in the paper. It is demonstrated that the geometrical tumor state is identical with the DNA plasmid state. Tumor chemotherapy intensity is obtained for therapy regimen with three cycles.

Keywords: tumor, soft matter, DNA plasmid, chemotherapy

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Ontology for Adaptive Test Generation

Anastasia Vangelova

Abstract: Generation of adaptive tests by ontologies is a relatively new area of the research. More and more e-learning systems are based on ontologies, as the ontologies allow a clear conceptualization of knowledge in a given area and multiple reuse. This paper is dedicated to the description of the developed ontology for programming language C with the needs of the adaptive system for testing of students. The ontology is designed to automatically generate tests from specified field. It can be easily extended by new classes for more detailed description of the language C and merged with other ontologies and thus cover more subject area.

Key words: adaptive tests, ontology, programming language C.

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