@article{MTMT:34822769,
	title = {Generalizing the concept of bounded variation},
	url = {https://m2.mtmt.hu/api/publication/34822769},
	author = {Goswami, Angshuman Robin},
	doi = {10.1007/s00010-024-01050-8},
	journal-iso = {AEQUATIONES MATH},
	journal = {AEQUATIONES MATHEMATICAE},
	volume = {2024},
	unique-id = {34822769},
	issn = {0001-9054},
	abstract = {Let [a,b]\subseteq \mathbb {R} [ a , b ] ⊆ R be a non-empty and non singleton closed interval and P=\{a=x_0<\cdots <x_n=b\} P = { a = x 0 < ⋯ < x n = b } is a partition of it. Then f:I\rightarrow \mathbb {R} f : I → R is said to be a function of r -bounded variation, if the expression \sum \nolimits ^{n}_{i=1}|f(x_i)-f(x_{i-1})|^{r} ∑ i = 1 n | f ( x i ) - f ( x i - 1 ) | r is bounded for all possible partitions like P . One of the main results of the paper deals with the generalization of the classical Jordan decomposition theorem. We establish that for r\in ]0,1] r ∈ ] 0 , 1 ] , a function of r -bounded variation can be written as the difference of two monotone functions. While for r>1 r > 1 , under minimal assumptions such a function can be treated as an approximately monotone function which can be closely approximated by a nondecreasing majorant. We also prove that for 0<r_1<r_2 0 < r 1 < r 2 , the function class of r_1 r 1 -bounded variation is contained in the class of functions satisfying r_2 r 2 -bounded variations. We go through approximately monotone functions and present a possible decomposition for f:I(\subseteq \mathbb {R}_+)\rightarrow \mathbb {R} f : I ( ⊆ R + ) → R satisfying the functional inequality f(x)\le f(x)+(y-x)^{p}\quad (x,y\in I \text{ with } x<y \text{ and } p\in ]0,1[ ). f ( x ) ≤ f ( x ) + ( y - x ) p ( x , y ∈ I with x < y and p ∈ ] 0 , 1 [ ) . A generalized structural study has also been done in that specific section. On the other hand, for \ell [a,b]\ge d ℓ [ a , b ] ≥ d , a function satisfying the following monotonic condition under the given assumption will be termed as d -periodically increasing f(x)\le f(y)\quad \text{ for } \text{ all }\quad x,y\in I\quad \text{ with }\quad y-x\ge d. f ( x ) ≤ f ( y ) for all x , y ∈ I with y - x ≥ d . We establish that in a compact interval any function satisfying d -bounded variation can be decomposed as the difference of a monotone and a d -periodically increasing function. The core details related to past results, motivation, structure of each and every section are thoroughly discussed below.},
	year = {2024},
	eissn = {1420-8903}
}

@article{MTMT:34820138,
	title = {Optimal strategies in fractional games: vertex cover and domination},
	url = {https://m2.mtmt.hu/api/publication/34820138},
	author = {Bujtás, Csilla and Rote, Günter and Tuza, Zsolt},
	doi = {10.26493/1855-3974.2771.4df},
	journal-iso = {ARS MATH CONTEMPOR},
	journal = {ARS MATHEMATICA CONTEMPORANEA},
	volume = {2024},
	unique-id = {34820138},
	issn = {1855-3966},
	year = {2024},
	eissn = {1855-3974},
	orcid-numbers = {Bujtás, Csilla/0000-0002-0511-5291}
}

@article{MTMT:34798546,
	title = {Examination of Accurate Exocentric Distance Estimates in a Virtual Environment Using a Desktop Display and the Gear VR},
	url = {https://m2.mtmt.hu/api/publication/34798546},
	author = {Guzsvinecz, Tibor and Szűcs, Judit and Perge, Erika},
	doi = {10.3390/electronics13081536},
	journal = {ELECTRONICS (SWITZ)},
	volume = {13},
	unique-id = {34798546},
	abstract = {Spatial perception plays a critical role in virtual worlds and real environments, as it can impact navigation abilities. To understand this influence, the conducted study investigated the effects of human characteristics and immersion levels on the exocentric distance estimation process in virtual environments. As the first step, a virtual environment was implemented for both desktop and Gear VR head-mounted displays. Afterward, the exocentric distance estimation skills of 229 university students were examined. Out of these students, 157 used the desktop display, and 72 used the Gear VR. Using logistic regression analysis and linear regression analysis methods, their effects on the probabilities of accurate estimates and their estimation times were investigated. According to the results, gender, video game playtime per week, height, and display device had significant effects on the former, whereas dominant hand, video game playtime per week, height, and display device had significant effects on the latter. The results also show that by using the head-mounted display, the likelihood of the students estimating exocentric distances accurately significantly decreased; however, they were significantly faster with it. These findings can influence the development of more accessible and effective virtual environments in the future.},
	keywords = {Virtual reality; Distance measurement; Mérési módszerek; virtuális valóság; Human in the loop; Ember-Számítógép Interakció; immersive experience},
	year = {2024},
	eissn = {2079-9292},
	pages = {1-23},
	orcid-numbers = {Guzsvinecz, Tibor/0000-0003-3273-313X; Szűcs, Judit/0000-0002-9828-3322; Perge, Erika/0000-0003-1285-1374}
}

@inbook{MTMT:34797365,
	title = {Massively Parallel EEG Algorithms for Pre-exascale Architectures},
	url = {https://m2.mtmt.hu/api/publication/34797365},
	author = {Wang, Zeyu and Juhász, Zoltán},
	booktitle = {Euro-Par 2023: Parallel Processing Workshops},
	doi = {10.1007/978-3-031-48803-0_34},
	unique-id = {34797365},
	year = {2024},
	pages = {290-295},
	orcid-numbers = {Juhász, Zoltán/0000-0003-0677-8588}
}

@article{MTMT:34780182,
	title = {Characterization of shadowing for linear autonomous delay differential equations},
	url = {https://m2.mtmt.hu/api/publication/34780182},
	author = {Pituk, Mihály and Stavroulakis, John Ioannis},
	doi = {10.21136/CMJ.2024.0191-23},
	journal-iso = {CZECH MATH J},
	journal = {CZECHOSLOVAK MATHEMATICAL JOURNAL},
	volume = {2024},
	unique-id = {34780182},
	issn = {0011-4642},
	year = {2024},
	eissn = {1572-9141},
	pages = {1-8}
}

@{MTMT:34777123,
	title = {Measurements in a roundabout},
	url = {https://m2.mtmt.hu/api/publication/34777123},
	author = {Medgyes, Krisztián and Kovács, Tamás},
	booktitle = {10th Winter School for PhD Students in Informatics and Mathematics},
	unique-id = {34777123},
	year = {2024},
	pages = {26}
}

@{MTMT:34777110,
	title = {Transportation and delivery optimization. the role of information technology in enhancing efficiency and sustainability},
	url = {https://m2.mtmt.hu/api/publication/34777110},
	author = {Medgyes, Ádám István and Medgyes, Krisztián},
	booktitle = {10th Winter School for PhD Students in Informatics and Mathematics},
	unique-id = {34777110},
	year = {2024},
	pages = {24-25}
}

@article{MTMT:34765170,
	title = {Shadowing, Hyers–Ulam stability and hyperbolicity for nonautonomous linear delay differential equations},
	url = {https://m2.mtmt.hu/api/publication/34765170},
	author = {Backes, Lucas and Dragičević, Davor and Pituk, Mihály},
	doi = {10.1142/S0219199724500123},
	journal-iso = {COMMUN CONTEMP MATH},
	journal = {COMMUNICATIONS IN CONTEMPORARY MATHEMATICS},
	volume = {2024},
	unique-id = {34765170},
	issn = {0219-1997},
	abstract = {It is known that hyperbolic nonautonomous linear delay differential equations in a finite dimensional space are Hyers–Ulam stable and hence shadowable. The converse result is available only in the special case of autonomous and periodic linear delay differential equations with a simple spectrum. In this paper, we prove the converse and hence the equivalence of all three notions in the title for a general class of nonautonomous linear delay differential equations with uniformly bounded coefficients. The importance of the boundedness assumption is shown by an example.},
	year = {2024},
	eissn = {1793-6683},
	orcid-numbers = {Backes, Lucas/0000-0003-3275-1311; Dragičević, Davor/0000-0002-1979-4344}
}

@article{MTMT:34765160,
	title = {Short-term system imbalance forecast using linear and non-linear methods},
	url = {https://m2.mtmt.hu/api/publication/34765160},
	author = {Balázs, István and Fodor, Attila and Magyar, Attila},
	doi = {10.1007/s12667-024-00667-7},
	journal-iso = {ENERGY SYSTEMS},
	journal = {ENERGY SYSTEMS: OPTIMIZATION MODELING SIMULATION AND ECONOMIC ASPECTS},
	volume = {2024},
	unique-id = {34765160},
	issn = {1868-3967},
	abstract = {The imbalance between supply and demand is a critical factor in the operation of the power system, as it leads to a change in the system frequency. Therefore, it is essential to be able to predict its value from historical, measured and forecast data. Based on the assumption that system imbalance is correlated with measured values of system variables as well as predictions of exogenous variables, this work proposes a multi-step version of the autoregressive distributed lag model for the short-term forecast of system imbalance. The proposed forecasting model has been compared with a long short-term memory network-based procedure as well as with an extratree regression model using real data. The results show that the proposed multi-step autoregressive forecasting model outperforms the others in all three evaluation metrics. Since, in many cases, it is sufficient to specify the sign of the imbalance, this paper introduces the concept of sign accuracy as a function of the predicted imbalance and evaluates it for the investigated solutions.},
	year = {2024},
	eissn = {1868-3975},
	orcid-numbers = {Magyar, Attila/0000-0003-0196-7646}
}

@article{MTMT:34762966,
	title = {Generally Applicable Q-Table Compression Method and Its Application for Constrained Stochastic Graph Traversal Optimization Problems},
	url = {https://m2.mtmt.hu/api/publication/34762966},
	author = {Kegyes, Tamás and Kummer, Alex and Süle, Zoltán and Abonyi, János},
	doi = {10.3390/info15040193},
	journal-iso = {INFORMATION-BASEL},
	journal = {INFORMATION (BASEL)},
	volume = {15},
	unique-id = {34762966},
	abstract = {We analyzed a special class of graph traversal problems, where the distances are stochastic, and the agent is restricted to take a limited range in one go. We showed that both constrained shortest Hamiltonian pathfinding problems and disassembly line balancing problems belong to the class of constrained shortest pathfinding problems, which can be represented as mixed-integer optimization problems. Reinforcement learning (RL) methods have proven their efficiency in multiple complex problems. However, researchers concluded that the learning time increases radically by growing the state- and action spaces. In continuous cases, approximation techniques are used, but these methods have several limitations in mixed-integer searching spaces. We present the Q-table compression method as a multistep method with dimension reduction, state fusion, and space compression techniques that project a mixed-integer optimization problem into a discrete one. The RL agent is then trained using an extended Q-value-based method to deliver a human-interpretable model for optimal action selection. Our approach was tested in selected constrained stochastic graph traversal use cases, and comparative results are shown to the simple grid-based discretization method.},
	year = {2024},
	eissn = {2078-2489},
	pages = {193},
	orcid-numbers = {Kegyes, Tamás/0000-0002-9003-7776; Kummer, Alex/0000-0002-6550-5101; Süle, Zoltán/0000-0002-5589-2355; Abonyi, János/0000-0001-8593-1493}
}