Search Everything

Tip: Search using "First Name + Last Name", e.g.
János Kiss instead of Kiss János.

Publications - 6278

Fuzzy flip-flops and neural nets?

Rita Lovassy László T. Kóczy

Publication Name: IEEE International Conference on Fuzzy Systems

Publication Date: 2007-12-01

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

J-K flip-flops are elementary digital units providing sequential features/memory functions. Their definitive equation is used both in the minimal disjunctive and conjunctive forms. Fuzzy connectives do not satisfy all Boolean axioms, thus the fuzzy equivalents of these equations result in two non-equivalent definitions, "reset and set type" fuzzy flip-flops (F3) by Hirota & al. when introducing the concept of F 3. The paper gives an overview of some of the most famous F 3-s by presenting their definitions and graphs. An interesting aspect of F3-s might be that they have a certain convergent behavior when one of their inputs (e.g. J) is exited repeatedly. This is true even if the other input (K) is kept at a constant value. The behavior is more versatile if both inputs are given a series of changing values. If J is considered the equivalent of the traditional input of a neuron (with an adder unit applied before J), K might play a secondary modifier's role, or can just be set fix. The paper encourages to the investigation of such possible F3-networks as new alternative types of neural networks. © 2007 IEEE.

Open Access: Yes

DOI: 10.1109/FUZZY.2007.4295435

S-shaped fuzzy flip-flops

Rita Lovassy László T. Kóczy

Publication Name: 8th International Symposium of Hungarian Researchers on Computational Intelligence and Informatics Cinti 2007

Publication Date: 2007-12-01

Volume: Unknown

Issue: Unknown

Page Range: 383-391

Description:

The multilayer perceptron is an artificial neural network that learns nonlinear function mappings. Nonlinear functions can be represented by multilayer perceptrons with units that use nonlinear activation functions. The neurons in the multilayer perceptron networks typically employ sigmoidal activation function. The next state of the J-K fuzzy flipflops (F3) using Fodor, Yager and Dombi operators present S-shaped characteristics. An interesting aspect of F3-s might be that they have a certain convergent behavior when one of their inputs (e.g. J) is exited repeatedly. If J is considered the equivalent of the traditional input of a neuron (with an adder unit applied before J), K might play a secondary modifier's role, or can just be set fix. The paper proposes the investigation of such possible F3-networks as new alternative types of neural networks.

Open Access: Yes

DOI: DOI not available

The possible applications of Fuzzy logic for the treatment of conflicts in the dispositional tasks of railway traffic control centers

Tibor Héray Gabor Rozsa László T. Kóczy

Publication Name: IEEE AFRICON Conference

Publication Date: 2007-12-01

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

the handling of traffic conflicts of trains is rather complicated if full dynamic models are used. Often it is senseless to take into consideration all details of the motion equations and environmental parameters especially as the main parameters, like maximum speed of the trains involved are not exactly known. Also, a large number of noise type variables are always available. The paper proposes the use of the Mamdani type fuzzy rule based reasoning algorithm for handling railway traffic conflicts. The essential point is the granulation of all important parameters into a relatively small number of categories labeled by terms such as small, large, etc. This way the possible decisions for a concrete traffic conflict situation get various fuzzy weights after accumulation of all the fired rules. The final (non-fuzzy) decision is taken by choosing the option with the largest weight. A simplified example is presented for a delay and overtaking type conflict. ©2007 IEEE.

Open Access: Yes

DOI: 10.1109/AFRCON.2007.4401624

Mechanism of cross-level settlements and void accumulation of wide and conventional sleepers in railway ballast

Szabolcs Fischer Mykola Sysyn Olga Nabochenko Norman Krumnow

Publication Name: Railway Engineering Science

Publication Date: 2024-09-01

Volume: 32

Issue: 3

Page Range: 361-383

Description:

The cross-level and twist irregularities are the most dangerous irregularity types that could cause wheel unloading with the risk of derailments and additional maintenance expenses. However, the mechanism of the irregularities initiation and development is unclear. The motivation of the present study was the previous experimental studies on the application of wide sleepers in the ballasted track. The long-term track geometry measurements with wide sleepers show an enormous reduction of the vertical longitudinal irregularities compared to the conventional track. However, wide sleepers had higher twist and cross-section level irregularities. The present paper aims to explain the phenomenon by discrete element method (DEM) modeling the development process of sleeper inhomogeneous support at cross-level depending on the sleeper form. The DEM simulations show that the maximal settlement intensity is up to 3.5 times lower for a wide sleeper in comparison with the conventional one. Nevertheless, the cross-level differential settlements are almost the same for both sleepers. The particle loading distribution after all loading cycles is concentrated on the smaller area, up to the half sleeper length, with fully unloaded zones under sleeper ends. Ballast flow limitation under the central part of the sleeper could improve the resilience of wide sleepers to the development of cross-level irregularities. The mechanism of initiation of the cross-level irregularity is proposed, which assumes the loss of sleeper support under sleeper ends. The further growth of inhomogeneous settlements along the sleeper is assumed as a result of the interaction of two processes: ballast flow due to dynamic impact during void closing and on the other side high pressure due to the concentration of the pressure under the middle part of the sleeper. The DEM simulation results support the assumption of the mechanism and agree with the experimental studies.

Open Access: Yes

DOI: 10.1007/s40534-024-00329-5

Finite Element Simulation Based Analysis of Valve-sparing Aortic Root Surgery

Tamás Umenhoffer B. Benyo Péter Somogyi K. Kovacs Róbert Nagy Bernhard Laufer Anikó Kubovje Ákos Szlávecz Tamás Szerafin

Publication Name: IFAC Papersonline

Publication Date: 2020-01-01

Volume: 53

Issue: 2

Page Range: 16037-16042

Description:

The valve-sparing aortic root surgery is frequently used in the treatment of aortic root enlargement or aortic root aneurysm. The currently used common surgical practice assumes that the valve leaflets are distributed evenly around the circle defined by the aorta wall which is frequently a false assumption according to hart anatomy studies. A finite element simulation based method is proposed in this study for the analysis of the alternative surgical outcomes of the valve-sparing aortic root surgery. The simulation methods allow the definition of the aortic valve leaflet commissure positions and the diameter of the graft used to replace the aortic root. The suggested methods are able to estimate and quantitatively compare the hemodynamic functions and the robustness of the aortic valve functions. The corresponding modeling environment makes possible the easy definition of the patient specific aortic root model that is used as an input of the simulation. The initial validation of the simulation method was done by a real patient data based simulation study. These results suggest that the currently used surgical practice can be improved.

Open Access: Yes

DOI: 10.1016/j.ifacol.2020.12.409

The Extension of the Triple Fuzzy Time Dependent Travelling Salesman Problem Model, with a Discrete Bacterial Memetic Optimization Algorithm

Boldizsar Tuu-Szabo Ruba Almahasneh László T. Kóczy

Publication Name: Acta Polytechnica Hungarica

Publication Date: 2025-01-01

Volume: 22

Issue: 5

Page Range: 71-91

Description:

The Traveling Salesman Problem (TSP) is one of the most often studied NP-hard graph search problems. There have been numerous publications in the literature that applied various approaches to find the optimum or semi optimum solution. Although the problem is computationally intractable, but the Time Dependent Traveling Salesman Problem (TD TSP) is one of the most realistic extensions of the original TSP problem. In the TD TSP, the costs of edges between nodes vary, namely, they are assigned higher costs if they crossed a predefined oblong shaped area (to represent the jam region in the city center). Realizing that the jam regions and the rush hours costs on a tour are uncertain and can never be accurately represented by concrete numbers, we introduced the novel 3FTD TSP (Triple Fuzzy Time Dependent Traveling Salesman Problem); a fully fuzzified model of the original TD TSP. The 3FTD TSP utilizes fuzzy values for determining the costs between any two nodes within the traffic jam regions and during the rush hours periods more precisely. In this paper, we extend the 3FTD TSP further and apply it on the biggest universal instances in the literature in pursuit of testing the generality and applicability of the 3FTD TSP on real-life scenarios. To support the claim of the model’s efficiency, we propose the application of the DBMEA (Discrete Bacterial Memetic Evolutionary Algorithm), as a meta-heuristic and the classic GA (Genetic Algorithm) enabling the reader to compare the accuracy and the speed of (quasi-) optimum solutions convergence.

Open Access: Yes

DOI: 10.12700/aph.22.5.2025.5.4

Mediumship and its Cognitive 'Survival' in Identification of Collective Individuation Part VI. Csontváry's Vision (Picture) of the Wailing Wall and Jung's Fatehpur Dream, a Comparison

Peter Varlaki Judit Ida Steiner-Varlaki Péter Baranyi

Publication Name: 10th IEEE International Conference on Cognitive Infocommunications Coginfocom 2019 Proceedings

Publication Date: 2019-10-01

Volume: Unknown

Issue: Unknown

Page Range: 587-596

Description:

In this part of the paper we intend to show a hermeneutical comparison between Csontváry's Wailing Wall picture and Jung's famous Fatehpur dream as characteristic manifestations of the collective individuation. We discuss their mainly unconscious participation mystique with Sabbatai Zwi and his 'theology' together with their interest in the 'David-Uriah' mythologem. Afterward we analyze the mediumship of Csontváry comparing with the mediumship of C. G. Jung and W. Pauli.

Open Access: Yes

DOI: 10.1109/CogInfoCom47531.2019.9089905

A literature outlook on the impacts of corporate social responsibility on sustainable banking operation

Katalin Czakó Arben Sahiti Erleta Halimi

Publication Name: International Journal of Green Economics

Publication Date: 2025-01-01

Volume: 19

Issue: 4

Page Range: 429-447

Description:

Corporate social responsibility (CSR) has become essential in banking as stakeholders demand greater sustainability, transparency, and ethical governance. This paper provides a structured review of studies from 2014–2024, examining the relationship between CSR initiatives and banks’ financial performance. The review highlights that CSR practices such as green banking, responsible lending, ethical investment strategies, and sustainability reporting can enhance profitability, reputation, and stakeholder trust though results vary across contexts. While many studies find a positive relationship between CSR and financial performance, others report negative or neutral effects, depending on bank size, institutional stability, cultural context, and the specific CSR dimensions pursued. Guided by stakeholder, legitimacy, resource-based, and reputation theories, the review develops an integrated conceptual framework and offers policy insights for banks and regulators. It also identifies research gaps, particularly the potential of emerging technologies like blockchain and artificial intelligence to strengthen ESG risk assessment and financial inclusion. Overall, CSR remains a key but context-dependent driver of sustainable banking.

Open Access: Yes

DOI: 10.1504/IJGE.2025.151327

THE ROLE OF GEOPARKS IN SUSTAINABLE TOURISM DEVELOPMENT: A CASE STUDY APPROACH

Lóránt Dávid Botond Géza Kálmán Szilárd Malatyinszki

Publication Name: Geojournal of Tourism and Geosites

Publication Date: 2025-01-01

Volume: 59

Issue: 2

Page Range: 572-586

Description:

This study aims to explore the role of geoheritage in sustainable tourism development by integrating geosites into tourism planning and analyzing their impact on local economies, environmental conservation, and community well-being, and visitor relaxation. The study also examines how the principles of a circular society, which emphasize resource regeneration and human well-being, can be applied to enhance the sustainability and appeal of geoheritage-based tourism. A mixed-methods approach was used, incorporating both qualitative and quantitative analyses. Case studies from Azores Geopark, Jeju Island Geopark, and Marble Arch Caves Geopark were selected to evaluate the socio-economic and environmental impacts of geoheritage-based tourism. The results indicate that geoheritage-based tourism significantly contributes to economic growth and environmental conservation, particularly when supported by strong community involvement and infrastructure development. Statistical analyses revealed positive correlations between visitor numbers and economic benefits, as well as between community engagement and conservation outcomes. Additionally, the promotion of relaxation at geosites was found to reinforce both environmental stewardship and visitor satisfaction, aligning with circular society principles by creating a regenerative tourism model. Geoheritage-based tourism promotes sustainable development by balancing economic, environmental, and social dimensions. The findings suggest that successful tourism management requires careful planning, infrastructure investment, and active community participation. This study did not include a comparative analysis of areas that are underutilized in terms of both geoheritage and geosites with tourism potential, primarily due to limited resources and time constraints. Incorporating such a comparison would offer valuable insights into the key conditions required for the successful development of geoheritage-based tourism. It is anticipated that future research will address these limitations by broadening the scope of case studies to include a more diverse range of geographical contexts. Moreover, future studies should seek to integrate qualitative approaches alongside quantitative approaches in order to better understand the wider social and cultural role and impacts of geoheritage-based tourism, which can thus be an important tourism product worldwide.

Open Access: Yes

DOI: 10.30892/gtg.59206-1438