Issue 1, Volume 2, 2008

New Artificial Neural Network based Test for the Detection of Past Population Expansion using Microsatellite Loci
by Krzysztof A. Cyran, Dariusz Myszor

Abstract: Detection of the past population growth is one of the crucial issues in contemporary population genetics. The importance of the problem is especially well understood in the context of neutral theory of evolution at molecular level proposed by Kimura. This theory often serves as neutral hypothesis in the search for genes which underwent natural selection. The conclusions in such studies can be false if population expansion was present but not detected and therefore not introduced into the model. In the paper we present novel statistical test which emerged from application of artificial neural networks theory. The test is designed to detect past population growths based on genetic microsatellite data. In experimental part of our research we created set of samples, using forward in time simulation methods. These samples were picked at random from simulated populations that had undergone growths of different types and intensities. Then, we created and trained series of different artificial neural networks and checked power of new tests based on these networks. We also compared powers of new tests with powers obtained by known methods based on microsatellites. Our studies showed that proposed by us new test provides better power in detection of population growth than the best currently available tests based on microsatellites i.e. Kimmel's and King's imbalance indices.
AStochastic computer simulations, population growth detection tests, artificial neural networks, microsatellite loci, single step mutation model.
Full Paper, pp. 1-9


Coalescent vs. Time-forward Simulations in the Problem of the Detection of Past Population Expansion
by Krzysztof A. Cyran, Dariusz Myszor

Abstract: The objective of this article is to show advantages and disadvantages of time-forward simulations as compared to the simulations performed backwards in time. The posed general issue is then narrowed to the problem of detection of past population expansion. The detection of population expansion is relevant in population genetics studies and there are plenty of methods used for that purpose. One of them utilizes genetic information preserved in microsatellites present in great abundance in the genome. We address the problem by simulating microsatellites evolution in different population growth scenarios. Namely we use time-forward computer simulation methods and compare results with results obtained by other researchers whiu used coalescent methodology. We argue that feed-forward simulation which are based on real life scenarios when succeeding generations are picked from the preceding one are becoming more and more suitable tool for population genetics with the increasing computational capabilities of contemporary computerss
Time-forward computer simulations, coalescent methods, population growth detection tests, short tandem repeat motifs
Full Paper, pp. 10-17


Design and Analysis of Various Models of RC5-192 Embedded Information Security Algorithm
by Omar Elkeelany

Abstract: This article presents the design and analysis of various hardware reconfigurable models of RC5 Encryption algorithm. The original contribution herein is to determine the effects of loop-unrolling design concept on improving the encryption performance. We show how we determined the optimal design value of the number of unrolled loops to implement the RC5 algorithm using 192-bit encryption key. The various models tested were based on single-custom processor with no-loop-unrolling and with various sizes of loop unrolled implementations. In this research, various performance measures were considered. Namely, these were; the maximum frequency of operation, circuit size, throughput and energy consumption. To achieve proper comparison results, all models were implemented in the same hardware reconfigurable chip, a Field Programmable Gate Array (FPGA). The performance metrics of each model were evaluated to determine the best hardware model. Verilog hardware description language was used to model and test all implementations. Results revealed that while no-loop-unrolling provided the least circuit size, the 3-loop-unrolled approach provided the highest encryption throughput. Further, a throughput speed up of 24% was achieved as compared to a reference system implemented in a similar target device using a Xilinx FPGA family. Comparing our implementations on the same Altera FPGA family, a maximum throughput speed up of 50% was achieved. These results provide a much better ground for applications involving high performance embedded data security, such as in military communications, nuclear digital instrumentation and control, and portable biomedical devices.
Cryptography, FPGA design and analysis, RC5 encryption, Loop-unrolling
Full Paper, pp. 18-27


Towards a Framework for Hotel Website Evaluation
by Mario Spremic, Ivan Strugar

Abstract: The growing importance of tourism industry in world economy reflects on tourism growing importance in Croatian economy as well. Tourism industry represents one of the areas in which Internet technology has a significant influence changing some of the key industry premises. Hotel website offers new opportunities for hoteliers. But it is essential to hoteliers to evaluate their web presence and to compare their quality with competition in the marketplace. Building evaluation framework and procedure for this purpose is not simple task. This paper presents one possible framework for hotel website evaluation performed to evaluate the Web sites of Croatian high class hotels and their content. The study results show that management of Croatian top hotels is still using Web and Internet technology for presentation purposes solely and there is no conscious that its content needs to be managed well. It is obvious that Internet is still not adequately understand, accepted and integrated within hotel management in Croatia. The absence of the very basic information about the hotel and their offer, e-mail form request for reservation information illustrate this hotel management attitude.
Tourism, hotel web sites quality, survey, Croatia
Full Paper, pp. 28-36


Issue 3, Volume 2, 2008

A Numerical Algorithm for a One-Dimensional Nonlinear Timoshenko System
by Jemal Peradze, Vladimer Odisharia

Abstract: We consider the boundary value problem for a system of nonlinear ordinary differential equations that describes the static behavior of a plate. An approximate solution is obtained using the algorithm including the Galerkin method, the convergence of which was proved by the authors previously, and the nonlinear Jacobi iteration process, the accuracy of which is discussed in this work.
Error estimate, Jacobi iteration process, nonlinear Timoshenko system, numerical algorithm
Full Paper, pp. 67-75


Profitability on the Financial Markets; A Discriminant Analysis Approach
by S. A. Ionescu, C. S. Murgoci, C. M. Gheorghe, E. Ionescu

Abstract: In this paper we tried to group in three classes the companies listed without interruption for 6 years from Bucharest Stock Exchange. We used cluster analysis, namely an iterative method of clustering, the k-means algorithm. Using data results, we have made tests for the three classes of prediction using discriminant analysis. Fisher's functions have helped us to make predictions on the affiliation of a new listed company on one of the 3 classes of risk. In this study, emphasis was placed on the liquidity of companies, but also on how efficient are used the raw materials, the basic elements in the current financial crisis. This should give us a clearer picture of companies that are ready to get over this difficult time.
Discriminant analysis, Cluster analysis, Pattern recognition, Stock exchange, Portfolio analysis, Classifiers
Full Paper, pp. 76-87


An Empirical Study on E-learning Note-Taking Platform Using Multimodal Metaphors
by Dimitrios Rigas, Mohamed Sallam

Abstract: This paper introduces an empirical study to investigate the effect of including multimodal metaphors such as text, graphic and speech in e-learning application. The aim of the experiment was to measure and compare the level of usability of textual and multimodal interfaces. The usability parameters which are efficiency, effectiveness, and users? satisfaction were considered in the study. In order to carry out comparative investigation, two independent groups were involved to evaluate two different interfaces of an experiment e-learning platform. First group (control) was consisted 22 participants using textual interface platform based on textual modal only. This platform used Microsoft Word 2007 and its „adding comments? feature as the modal. The second platform was based on a multimodal interface used by the experimental group and consisted of three multimodality tools to improve efficiency of e-learning. The modalities used by this experimental group were text, speech and graphics. The results obtained from this investigation have shown that the multimodal e-learning interface group increased the level of usability by taken lower time to complete the experimental tasks and performed successfully higher number of tasks, and more satisfied than the textual interface group. However, the error rate in the experimental group was found to be greater than that of the control group. The results also suggested that other multimedia metaphors could be used for enhancement and improvement the performance of e-learning system. These metaphors could include the use of combinations of graphic, recorded speech and earcons.
E-learning, Usability, User interface, Multimodal Interaction
Full Paper, pp. 88-95


Limited Receptive Area Neural Classifier based Image Recognition in Micromechanics and Agriculture
by Tatiana Baidyk, Ernst Kussul, Oleksandr Makeyev, Alejandro Vega

Abstract: Two multi-purpose image recognition systems based on neural classification are proposed. First application is an image recognition based adaptive control system for micromechanics where the limited receptive area (LIRA) neural classifier is proposed for texture recognition of mechanically treated metal surfaces. The performance of the proposed classifier was tested on image database of 80 images of four texture types corresponding to metal surfaces after milling, polishing with sandpaper, turning with lathe and polishing with file. The promising recognition rate of 99.8% was obtained for image database divided in half into training and validation sets. The second application is agriculture, where vast amounts of pesticides are used against the insects. In order to decrease the required amount of pesticides it is necessary to locate the precise form distribution of the insects and larvae. In this case the use of pesticides will be local. In order to automate the task of recognition of larvae we propose to use a web-camera based computer vision system. We tested the proposed system on image database of larvae of different forms, sizes and colors, distributed in different amounts and positions and containing 79 images. The main idea was to recognize the difference between the textures corresponding to the larvae and real world background. Recognition rate of 90.36% was obtained with only 10 images used for training and the rest of the image database used for validation suggesting high potential of the proposed approach. In this article we present the structure and the algorithms of recognition with LIRA neural classifier, and results of its application in both tasks.
Agriculture, image recognition, larvae, LIRA, micromechanics, neural classifier
Full Paper, pp. 96-103




Issue 2, Volume 2, 2008

P2P Audio/Video Protocol with Global Positioning Data in Real Time for Mobile Devices
by Jose-Vicente Aguirre, Rafael Alvarez, Leandro Tortosa, Jose-Francisco Vicent

Abstract: In this paper, we propose an original method to geoposition an audio/video stream with multiple emitters that are at the same time receivers of the mixed signal. The obtained method is suitable when a list of positions within a known area is encoded with precision tailored to the visualization capabilities of the target device. Nevertheless, it is easily adaptable to new precision requirements, as well as parameterized data precision. This method extends a previously proposed protocol, without incurring in any performance penalty.
Codification, geodesic coordinates, Multiparty, Stream, VoIP, Videoconference, P2P, Security, Pocket PC, Smart Phone, PDA
Full Paper, pp. 37-46


Monotone Systems Approach in Inductive Learning
by Peeter Roosmann, Leo Vohandu, Rein Kuusik, Tarvo Treier, Grete Lind

Abstract: In this paper we present a new approach for machine learning (ML) task solution based on Monotone Systems Theory, an inductive learning algorithm named by the authors as MONSIL (MONotone Systems in Inductive Learning). It has some advantages compared with several ML algorithms as rules overlapping, it can use several pruning techniques etc. The algorithm MONSIL usually produces more rules than other ML algorithms and it means that it would be more work-consuming than others, but as our experiments show, MONSIL works quite effectively.
In the paper we define also main terms of monotone systems theory, describe how to create monotone system to the data table and describe main advantages of the monotone systems approach. We also prove that concept description found by MONSIL is complete and consistent, explain algorithm’s main steps on examples and discuss results of experiments comparing MONSIL effectiveness with well-known ID3.
Inductive learning, Machine learning, Machine learning algorithm, Monotone systems theory
Full Paper, pp. 47-56


A Secret Sharing Scheme Based on Exponentiation in Galois Fields
by Clara M. Gallardo, Leandro Tortosa, Jose F. Vicent, Antonio Zamora

Abstract: To provide more efficient and flexible alternatives for the applications of secret sharing schemes, this paper describes a threshold sharing scheme based on exponentiation of matrices in Galois fields. A significant characteristic of the proposed scheme is that each participant has to keep only one master secret share which can be used to reconstruct different group secrets according to the number of threshold values.
Computer security, cryptography, public-key cryptography, threshold schemes, prepositioned secret sharing
Full Paper, pp. 57-66


Issue 4, Volume 2, 2008

The Error of the Galerkin Method for a Nonhomogeneous Kirchhoff Type Wave Equation
by Jemal Peradze

Abstract: The paper deals with the boundary value problem for a nonlinear integro-differential equation describing the dynamic state of a beam. To approximate the solution with respect to a spatial variable, the Galerkin method is used, the error of which is estimated. At the end of the paper a difference-iteration technique of solving the Galerkin system is presented.
Nonlinear beam equation, approximate algorithm, Galerkin method, error estimate
Full Paper, pp. 105-113


Algorithms of Approximate Solving of Some Linear Operator Equations Containing Small Parameters
by Archil Papukashvili, Gela Manelidze

Abstract: In the paper algorithms of approximate solving of some linear operator equations containing small parameters are described. In particular, an asymptotic method and an alternative variant of the asymptotic method are used. Algorithms and program products represent a new technology of approximate solving of system of linear algebraic equations, two–point boundary value problem, some linear nonhomogeneous integro-differential equations and singular integral equations containing an immovable singularity.
Nonhomogeneous operator equation, orthogonal series, asymptotic method, alternative method
Full Paper, pp. 114-122