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- ItemPhishing detection on webpages in European non-English languages based on machine learning(2025-10-27) Komosný, DanMachine learning-based phishing detection is crucial for preventing zero-day attacks. State-of-the-art phishing detection performs well on English webpages. However, it is not adequately accurate for webpages in minor languages. This work significantly improves phishing detection in European countries where minor languages are predominantly spoken. The proposed language-based phishing detection outperforms state-of-the-art methods for webpages in minor languages, achieving 99% accuracy on local webpages in the following countries: the Czech Republic, Denmark, Estonia, Croatia, Hungary, Lithuania, Latvia, Poland, Romania, Serbia, Slovakia, and Slovenia. The main improvement lies in reducing the false positive rate, where local benign webpages are incorrectly identified as phishing. The proposed method reduces the false positive rate by up to a factor of 10 for webpages in minor languages. The results are statistically robust across different webpage sets, scaled for real-world use. The Shapiro-Wilk test confirms a normal distribution of the results in each tested country, with p-values consistently above 0.05. Paired T-tests yield p-values consistently below 0.05, indicating statistically significant improvements in each country. The low variability in the results further demonstrates the robustness of the proposed method. To foster reproducibility, the source code, datasets, and raw results are made publicly available, including approximately two million local webpages from 16 countries. Reference data from English-speaking and major-language-speaking countries are also included. This work advances phishing detection for webpages in minor languages and contributes to more inclusive global cybersecurity.
- ItemParkinson Disease Detection from Speech Articulation Neuromechanics(Frontiers, 2017-08-25) Gomez-Vilda, Pedro; Mekyska, Jiří; Manuel Ferrandez, Jose; Palacios-Alonso, Daniel; Gómez-Rodellar, Andrés; Rodellar Biarge, María Victoria; Galáž, Zoltán; Smékal, Zdeněk; Eliášová, Ilona; Košťálová, Milena; Rektorová, IrenaAim: The research described is intended to give a description of articulation dynamics as a correlate of the kinematic behavior of the jaw-tongue biomechanical system, encoded as a probability distribution of an absolute joint velocity. This distribution may be used in detecting and grading speech from patients affected by neurodegenerative illnesses, as Parkinson Disease. Hypothesis: The work hypothesis is that the probability density function of the absolute joint velocity includes information on the stability of phonation when applied to sustained vowels, as well as on fluency if applied to connected speech. Methods: A dataset of sustained vowels recorded from Parkinson Disease patients is contrasted with similar recordings from normative subjects. The probability distribution of the absolute kinematic velocity of the jaw-tongue system is extracted from each utterance. A Random Least Squares Feed-Forward Network (RLSFN) has been used as a binary classifier working on the pathological and normative datasets in a leave-one-out strategy. Monte Carlo simulations have been conducted to estimate the influence of the stochastic nature of the classifier. Two datasets for each gender were tested (males and females) including 26 normative and 53 pathological subjects in the male set, and 25 normative and 38 pathological in the female set. Results: Male and female data subsets were tested in single runs, yielding equal error rates under 0.6% (Accuracy over 99.4%). Due to the stochastic nature of each experiment, Monte Carlo runs were conducted to test the reliability of the methodology. The average detection results after 200 Montecarlo runs of a 200 hyperplane hidden layer RLSFN are given in terms of Sensitivity (males: 0.9946, females: 0.9942), Specificity (males: 0.9944, females: 0.9941) and Accuracy (males: 0.9945, females: 0.9942). The area under the ROC curve is 0.9947 (males) and 0.9945 (females). The equal error rate is 0.0054 (males) and 0.0057 (females). Conclusions: The proposed methodology avails that the use of highly normalized descriptors as the probability distribution of kinematic variables of vowel articulation stability, which has some interesting properties in terms of information theory, boosts the potential of simple yet powerful classifiers in producing quite acceptable detection results in Parkinson Disease.
- ItemSeries-, Parallel-, and Inter-Connection of Solid-State Arbitrary Fractional-Order Capacitors: Theoretical Study and Experimental Verification(IEEE, 2018-02-27) Kartci, Aslihan; Agambayev, Agamyrat; Herencsár, Norbert; Salama, Khaled NabilIn the paper, general analytical formulas are introduced for the determination of equivalent impedance, magnitude, and phase, i.e. order, for n arbitrary fractional-order capacitors (FoCs) connected in series, parallel, and their interconnection. The approach presented helps to evaluate these relevant quantities in the fractional domain since the order of each element has a significant effect on the impedance of each FoC and their equivalent capacitance cannot be considered. Three types of solid-state fractional-order passive capacitors of different orders, using ferroelectric polymer and reduced Graphene Oxide-percolated P(VDF-TrFE-CFE) composite structures, are fabricated and characterized. Using an impedance analyzer, the behavior of the devices was found to be stable in the frequency range 0.2MHz–20MHz, with a phase angle deviation of ±4 degrees. Multiple numerical and experimental case studies are given, in particular for two and three connected FoCs. The fundamental issues of the measurement units of the FoCs connected in series and parallel are derived. A MATLAB open access source code is given in Appendix for easy calculation of the equivalent FoC magnitude and phase. The experimental results are in good agreement with the theoretical assumptions.
- ItemPerformance Analysis of Oustaloup Approximation for the Design of Fractional-Order Analogue Circuits(IEEE, 2018-11-05) Koton, Jaroslav; Stavnesli, Jorgen Hagset; Freeborn, ToddThe description and definition of various systems using fractional-order calculus continues to gain attention in a variety of field of engineering. This is especially true for the design of analogue function blocks, where the factional-order Laplace operator s , whereas 0 < < 1, is frequently used to design the fractional to design the transfer functions of these blocks. In this paper we focus on analysing the Oustaloup approximation of s to provide a tool that can support selecting the appropriate approximation to obtain a response that satisfies the designers’ requirements of approximation error in magnitude and/or phase in a specific frequency range for the minimal possible order N of the approximation
- ItemNew Compact VM Four-Phase Oscillator Employing Only Single Z-Copy VDTA And All Grounded Passive Elements(Kaunas University of Technology, 2013-12-16) Herencsár, Norbert; Šotner, Roman; Koton, Jaroslav; Mišurec, Jiří; Vrba, KamilIn this paper, a new compact voltage-mode four-phase oscillator employing single z-copy voltage differencing transconductance amplifier (ZC-VDTA) and only grounded passive elements is introduced. The use of only grounded capacitors and resistors makes the proposed circuit ideal for integrated circuit implementation. The condition of oscillation and the frequency of oscillation are independently adjustable. The passive and active sensitivities of the proposed circuit configuration are low. Experimental measurement results using readily available Maxim Integrated ICs MAX435 are given to prove the theory.