Publications

  1. Gocheva-Ilieva, S., Ivanov, A., Kulina, H., Stoimenova-Minova, M. Multi-Step Ahead Ex-Ante Forecasting of Air Pollutants Using Machine Learning, Mathematics, vol. 11, No. 7:1566, ISSN 2227-7390, 2023. DOI: 10.3390/math11071566, IF 2021 = 2.592, Q1, Scopus.

    https://www.mdpi.com/2227-7390/11/7/1566

  2. Boyoukliev, I., Kulina, H., Gocheva-Ilieva, S., Modelling and Forecasting of EUR/USD Exchange Rate Using Ensemble Learning Approach, Cybernetics and information technologies, Vol. 22, No 4, pp. 142-151, Print ISSN: 1311-9702; Online ISSN: 1314-4081, Sofia, 2022. DOI: 10.2478/cait-2022-0044, SJR 2021 = 0.42, Q2, Scopus.

    https://sciendo.com/es/article/10.2478/cait-2022-0044


  3. Gocheva-Ilieva, S., Yordanova, A., Kulina, H., Predicting the 305-day milk yield of Holstein-Friesian cows depending on the conformation traits and farm using simplified selective ensembles, Mathematics, vol. 10 (8): 1254, ISSN: 2227-7390, 2022. DOI:10.3390/math10081254. IF 2.592 (2021), Q1, Scopus.

    https://www.mdpi.com/2227-7390/10/8/1254

  4. Gocheva-Ilieva, S., Kulina, H., Yordanova, A., Stacking machine learning models using factor analysis to predict the output laser power, Proceedings of the International Conference on Electrical, Computer, Communications and Mechatronics Engineering (ICECCME), 16-18 November 2022, Maldives, ISBN: 978-1-6654-7095-7, 2022. DOI: 10.1109/ICECCME55909.2022.9988552. Publisher: IEEE, Scopus.

    https://ieeexplore.ieee.org/document/9988552

  5. Kulina, H., Koleva-Petrova, M., Gocheva-Ilieva, S., Ensemble learning for predicting the tensile strength of alloy steels from chemical composition and processing parameters, Proceedings of the International Conference on Electrical, Computer, Communications and Mechatronics Engineering (ICECCME), 16-18 November 2022, Maldives, ISBN: 978-1-6654-7095-7, 2022.DOI: 10.1109/ICECCME55909.2022.9988668. Publisher: IEEE, Scopus.

    https://ieeexplore.ieee.org/document/9988668

  6. Madamlieva, E., Kiskinov, H., Petkova, M., Zahariev, A., On the preservation with respect to nonlinear perturbations of the stability property for nonautonomous linear neutral fractional systems with distributed delays. Mathematics, vol. 10, No. 15: 2642, ISSN 2227-7390, 2022. DOI: 10.3390/math10152642, IF 2021 = 2.592, Q1, Scopus.

    https://www.mdpi.com/2227-7390/10/15/2642

  7. Kiskinov, H., Milev, M., Zahariev, A., About the resolvent kernel of neutral linear fractional system with distributed delays, Mathematics, vol. 10, No. 23: 4573, ISSN 2227-7390, 2022. DOI: 10.3390/math10234573, IF 2021 = 2.592, Q1, Scopus.

    https://www.mdpi.com/2227-7390/10/23/4573

  8. Kiskinov, H., Madamlieva, E., Veselinova, M., Zahariev, A., Integral representation of the solutions for neutral linear fractional system with distributed delays, Fractal and Fractional, Vol. 5, No. 4: 222, ISSN 2504-3110, 2021. DOI: 10.3390/fractalfract5040222, IF 2021 = 3.577, Q1, Scopus.

    https://www.mdpi.com/2504-3110/5/4/222

  9. Koleva-Petrova, M., Kulina, H., Dobrev, G., Gocheva-Ilieva, S., Ensemble models for predicting the hardness of alloy steels. AIP Conf. Proc. Vol. 2953, 040007, 2023. Published by AIP Publishing. ISBN: 978-0-7354-4720-2. SJR 0.152 /2023, Scopus.

    https://doi.org/10.1063/5.0178920

  10. Gocheva-Ilieva, S., Kulina, H., Koleva-Petrova, M., Machinability Study of AISI Low Alloy Steels Using Classification and Machine Learning Approaches, International conference on mathematical applications ICMATAP, 27.04.2023, Tokyo. Telematique, Vol. 22, No. 01, pp. 2207–2218, 2023. ISSN: 1856-4194, WoS (Clarivate Analytics, Emerging Sources citation index)

    https://www.provinciajournal.com/index.php/telematique/article/view/1453

  11. Kulina, H., Gocheva-Ilieva, S., Yaneva, P. CART Ensemble and Bagging Algorithm for Estimating of Factors Influencing the Furniture Market, International conference on mathematical applications ICMATAP, Telematique, Vol. 22, No. 01, pp. 1652–1663, 2023. ISSN: 1856-4194,WoS (Clarivate Analytics, Emerging Sources citation index)

    https://www.provinciajournal.com/index.php/telematique/issue/view/45

  12. Boyoukliev, I., Kulina, H., Gocheva-Ilieva, S. Forecasting volatility of bank deposits of individuals using hybrid Arcing -ARIMA approach, ACM ICoMS '23: Proceedings of the 2023 6th International Conference on Mathematics and Statistics, ACM International Conference Proceeding Series (ACM ICPS), pp. 56–62, 2023.

    https://doi.org/10.1145/3613347.3613356 , ISBN: 979-8-4007-0018-7. SJR 0.253/2023, Scopus.

  13. Boyoukliev, I., Gocheva-Ilieva, S. Statistical modeling and forecasting bank deposit data using Random Forests. Sciences of Europe, vol. 129, pp. 124-130, 2023. ISSN: 3162-2364.

    https://doi.org/10.5281/zenodo.10209391

  14. Koleva, S., Gocheva-Ilieva, S., Kulina H., Stochastic modelling of daily air pollution in Burgas, Bulgaria, 15th Conference of the Euro-American Consortium for Promoting the Application of Mathematics in Technical and Natural Sciences (AMiTaNS 2023) 21/06/2023 - 26/06/2023 Black-Sea resort of Albena, Bulgaria, J. Phys.: Conf. Ser., Vol. 2675, 012003, IOP Publishing.

    https://doi.org/10.1088/1742-6596/2675/1/012003 Open Access, SJR 0.180 /2023, Scopus.

  15. Yaneva, P., Kulina H. Furniture market demand forecasting using machine learning approaches, 2023, 15th Conference of the Euro-American Consortium for Promoting the Application of Mathematics in Technical and Natural Sciences (AMiTaNS 2023) 21/06/2023 - 26/06/2023 Black-Sea resort of Albena, Bulgaria, J. Phys.: Conf. Ser., Vol. 2675 (1), 012008, ISSN 17426588, https://iopscience.iop.org/article/10.1088/1742-6596/2675/1/012008, Open Access, SJR 0.180 /2023, Scopus.

  16. Valkova E., Atanasov V., Marinova M.H., Yordanova A., Yakimov K., Kutsarov Y. Application of Crustaceans as Ecological Markers for the Assessment of Pollution of Brackish Lakes of Bulgaria Based on Their Ability to Accumulate the Heavy Metals Cd, Zn and Ni, Limnological Review. 2024; 24(3):282-300.

    https://doi.org/10.3390/limnolrev24030017 Open Access, SJR 0.22 /2023, Scopus, WoS Q3

  17. Kiskinov, H., Madamlieva, E., Zahariev, A. Hyers-Ulam and Hyers-Ulam-Rassias stability for linear fractional systems with Riemann-Liouville derivatives and distributed delays. Axioms, Vol. 12 (2023), No. 7, 637, ISSN 2075-1680, https://doi.org/10.3390/axioms12070637 (registering DOI) - 27 Jun 2023, (Web of Science, IF 2023 = 1.900 – Q1), (SCOPUS, SJR 2022 = 0.388).

  18. Kiskinov, H., Milev, M., Veselinova, M., Zahariev, A. Continuous dependence on the initial functions and stability properties in Hyers-Ulam-Rassias sense for neutral fractional systems with distributed delays. Fractal Fract., Vol. 7 (2023), No. 10, 742, ISSN 2504-3110, https://doi.org/10.3390/fractalfract7100742, (Web of Science, IF 2023 = 3.600 – Q1), (SJR 2022 = 0.627).

  19. Kiskinov H., Madamlieva E., Veselinova M., Zahariev A., On variation of constant formulae for linear fractional delayed system with Lebesgue integrable initial conditions, AIP Conference Proceedings 2939, 040001 (2023), https://doi.org/10.1063/5.0178529, ISSN 1551-7616, ISSN 0094-243X, ISSN 0000-1984, ISSN 0000-2005, ISSN 0000-1983,(WoS), (SCOPUS, SJR 2022 = 0.164).

  20. Kiskinov, H., Milev, M., Petkova, M., Zahariev, A. Variable-order fractional linear systems with distributed delays—existence, uniqueness and integral representation of the solutions. Fractal Fract. 2024, 8, 156. ISSN 2504-3110, https://doi.org/10.3390/fractalfract8030156, (Web of Science, IF 2023 = 3.600 – Q1), (SJR 2022 = 0.627).

  21. Kiskinov, H., Milev, M., Cholakov, S., Zahariev, A. Fundamental matrix, integral representation and stability analysis of the solutions of neutral fractional sistems with derivatives in Riemann-Liouville sense. Fractal Fract. 2024, 8, 195. ISSN 2504-3110, https://doi.org/10.3390/fractalfract8040195 , (Web of Science, IF 2023 = 3.600 – Q1), (SJR 2022 = 0.627).

  22. Kulina, H., Yaneva, P., Gocheva-Ilieva, S. (2024). Modeling the Beer Market in a Competitive Environment with Principal Component Analysis and Machine Learning Techniques: A Case Study. In Proceedings of the 2024 7th International Conference on Mathematics and Statistics (pp. 114-120). ACM International Conference Proceeding Series, ISBN: 979-8-4007-0722-3 https://doi.org/10.1145/3686592.3686612, WoS, Scopus

  23. Kiskinov, H., Milev, M., Petkova, M., Zahariev, A. (2025). Boundedness and different types of stability of the solutions of linear fractional systems with distributed delays. In AIP Conference Proceedings (Vol. 3182, No. 1, p. 030006). AIP Publishing LLC. Proceedings of the 49th international conference “applications of mathematics in engineering and economics”, ISSN: 0094-243X (print), ISSN: 1551-7616 (online) https://doi.org/10.1063/5.0245995, Scopus SJR 0.152 (2023)

  24. Boyoukliev, I. (2024). Modeling and research of foreign exchange financial markets https://procedures.uni-plovdiv.bg/docs/procedure/2945/1926268361252900230.pdf

  25. Boyoukliev, I., Ivanova, V., Kulina, H., & Zlatanov, B. (2025). Integrating Economic Indicators and Machine Learning for Exchange Rate Forecasting. Computer Science and Interdisciplinary Research Journal, 2(2). https://doi.org/10.70862/CSIR.2025.0202-16