Monthly Archives: May 2008

Investigation of Database Access by Web Service

Daniela Gotseva

Abstract: The aim of this paper is to investigate database access, realized in two ways.’ direct by OLEDB, and indirect via web service. The research is included analysis and development of differ- ent database access into web application. Database schemE3 fS ITIOdeIed and normdlfzed for the purpose of research. Necessary objects are discussed and sample is created using graphical visu- alization of the results. This paper provided an attempt to develop strategies for database access from web application.
Key words: database, OLEDB, web service.

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Examination of Reliability and Discrimination Index of Test Items for Knowledge Assessment

Gospodin Jelev, Daniela Minkovska, Yoana Minkova

Abstract: The article presents  an examination  of test quality.  This tast is for students’  knowledge assessment  and  was  carried  out  in  two  universities.   The  methods  for  estimation  of  the  test reliability  are briefly  overviewed.  By  well grounded  selection  of the most  appropriate  method,  the test reliability is estimated.  The discrimination index of each test item is calculated and analysed. Keywords: assessment,  tests,  discrimination  index,  reliability

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An Access to Relational and SSD – Data Base by XML Transformations

Bozhidar Georgiev, Adriana Georgieva

“What do you get when you mix automata theory, mathematical logic
and database theory in a big bowl and stir it vigorously?
The answer is a foundation of XML.”

Leonid Libkin
University of Edinburgh, Scotland

Abstract: This paper presents an approach to provide an access to the relational database’s components by means of metalanguage XML. For this purpose are suggested several of XML-constructions — elements and attribute structures for database presentation (tables, record, fields with different types of data, keys and others). The problems about the distinctions between relational database’s structure and semi-structured data (ssd) are discussed. An example schema of WEB-based system, in which the implementation of XML-standard leads to better balance in mutual connections between distant servers, operating systems and applications, is shown. This allows the choice of the most suitable software technologies for the different servers. In the presented experimental example is shown XML-model of SQL-query (wrapping model). Here is depicted the whole route from sending of query to receiving of appropriate results in browser and this process is traced in details. The article submits some basic examples showing the main features and advantages of this mechanism and its usage in practice.
Key words: Extensible Markup Language (XML), Extensible Style Sheets Language for Transformations (XSLT), Simple API XML (SAX), Wireless Markup Language (WML), Syntax Analyzer (Parser), Uniform Resource Identifier (URI), ›ve//-formed X/\fL, DTD (Document Type Definition), W3C ( World Wide Web Consortium), URL (Uniform Resource Locator).

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XML-Based Session Reconstruction for Adaptive Web-Based Systems

Juliana Georgieva, Bujar Raufi, LuIe Ahmedi, Florije lsmaili, Xhemal Zenuni

Abstract: Web usage mining has recent years played a major role in monitoring and analyzing user behavior in web environment. This specialized field in data mining has helped a lot in giving valuable insights in sense of fitting user information needs and helping in gradual improvement of a web site. Adaptive web based systems, tend to adapt their content, based on user  access and navigation patterns. In order to perform the former, a thorough analysis of web server logs needs to be performed. XML as a technology designed specifically to share data in web environments, can offer great deal of flexibility in analyzing the web server logs for performing session reconstruction. In this paper, a suitability of XML and XSLT transformations has been tested and proven to be promising for performing (XML-based) session reconstruction on large amount of web server log data.“ A time-based heuristic model has been adopted to mapping user request activities into XML sessions. Further, a so-called Session Identification using XML (SIOUX) algorithm is presented followed by the description of the XSLT request aggregation strategy used. Finally, a case study of a web site usage and the experimental results collected illustrate the suitability of our approach. Here, a substantial amount of web server logs has been collected and first cleaned from unnecessary data, to then be submitted to our SIOIJX algorithm and the XSLT-based request aggregation engine which maps each request to a unique session and hence reconstructs the sessions.

Keywords: Session Reconstruction,  Adaptive  Web Based Systems, XML, XSLT-Transformations

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Reconstruction of Facial Images by Using Facial Motion and Image Processing Techniques

Baki Koyuncu, Umran Funda Akdogan

Abstract: Facial expressions (facial motions) were used to predict the original face image (OI) by using two different search algoritms.” Full search and three step search. Motion vectors were de- termined between the face image, OI, and its moved version, (MI), at a point in time. By using these vectors a face image was reconstructed (RI).  RI and OI were compared and it was seen that the full search algorithm has given a better similarity between OI and RI with respect to three step search algorithm.

Keywords: Mofion vector, facial motion, block matching,  full search,  three step search.

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Recognition of Astronomical Objects for Photometric and Astrometric Purposes Using Parallel Computations

Milena Lazarova, Irina Nikolova

Abstract:Parallel algorithmic model for astronomical objects recognition is suggested in the paper. The analyses are aimed to find all astronomical objects in an image,  to make photometric meas- urements and to build a catalog of the objects’ features that will be used  in  further  astrometric and/or photometric analyses. The suggested parallel computational model is based on data de- composition and uses a combination of parallel algorithmic  paradigms “master-slave”  and SPMD. The experimental results on a cluster of symmetric multiprocessors and the communication profiles show that the suggested parallel model scales well in respect to both the workload and the cluster size.

Key words: astronomical objects, astrometric and photometric analyses, parallel computations, message passing,  SPMD, manager-worker,  cluster

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Facial Animation Models: Characteristics of Existing Methods and Techniques

Vesselin Gueorguiev, Desislava Georgieva

Abstract:The first 3D computer animation model of the human face was created by Parke in 1972. Subsequent facial models and techniques for control facial animation have been developed over the years. This paper is aimed at making a survey of methods and techniques for facial modeling and facial animation. This observation is based on analysis of major characteristics of the human faces as an object of modelling and animation. Special part of this material is oriented to methods for facial description together with methods for human head 3D modeling. The observation of methods for 3D photorealistic human  head  animation  process  control  is  included  as  well.

Key words: facial animation,  facial model, character animation.

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Knowledge Representation and Reasoning Capabilities in Natural Language Processing Systems

Diana Grigorova, Nikolay Nikolov

Abstract:This paper presents a short analysis of the basic methods for knowledge representation in the systems with artificial intelligence. The pros and cons of every method have been reviewed. Reasoning capabilities of the methods are discussed, too. Based on the analysis made in the pa- per, a frame knowledge representation for the application has been chosen. The application itself is an analyzer of natural language sentences. An example illustrates the capabilities of the created analyzer, which is both problem-  and language- independent.

Key words: knowledge representation, reasoning, first order predicate logic, frames, description logics

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Parallel Solving of the Knapsack Combinatorial Problem with Metaheuristics

Plamenka Borovska, Shada Magbar

Abstract: In this paper we have suggested models of parallel computations for the knapsack opti- mization problem. The first model is based on simulated annealing metaheuristics and supports parallel independent moves. The second suggested model implies distributed evolutionary compu- tations of structured populations with elite chromosome migration. Both models are verified on the basis of flat MPI-based parallel program implementations on computer cluster. Parallelism profiling, scalability evaluation and analysis have been made scaling the problem size and the size of the parallel hardware. The quality of solution evaluation has been performed on the basis of 30 runs of the flat parallel program.

Key words: parallel optimization, combinatorial problems, knapsack problem, parallel metaheuris-tics, parallel performance,  quality of solution

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NURBS Models Development of Quadratic Surfaces for 30 Graphics Systems

Emiliyan Petkov

Abstract: The article examines the creation of appropriate models for design of  surfaces  that contains specific features. Real objects that have to be modeled in the 3D  graphics  systems possess those features. This research is orientated to the graphics systems, requiring NURBS modeling and enforcing the development of the new models of surfaces. Five of the nine surfaces that are presented by one general equation and possess specific optical features are examined in this report. On the base  of the new models presented here plugins for one 3D graphics system were developed.

Key words: 3D graphics systems, quadratic surfaces, NURBS models.

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