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Found 6273 publications

Hardware implementation of fuzzy flip-flops based on łukasiewicz norms

Publication Name: Proceedings of the 9th Wseas International Conference on Applied Computer and Applied Computational Science Acacos 10

Publication Date: 2010-12-01

Volume: Unknown

Issue: Unknown

Page Range: 196-201

Description:

The digital hardware implementation of various fuzzy operations furthermore of fuzzy flip-flops has been the subject of intense study and application. The fuzzy D flip-flop derived from fuzzy J-K one is a single input - single output unit with sigmoid transfer characteristics in some particular cases, proper to use as neuron in a Fuzzy Neural Networks (FNN). In this paper we propose the hardware realization of fuzzy D flip-flops based on Łukasiewicz norms.

Open Access: Yes

DOI: DOI not available

Smart economy and startup enterprises in the visegrád countries—a comparative analysis based on the crunchbase database

Publication Name: Smart Cities

Publication Date: 2020-12-01

Volume: 3

Issue: 4

Page Range: 1477-1494

Description:

The present study seeks to explore the concept of “smart economy” through the definition of the smart city. It also presents smart city subsystems and the smart city model. It focuses on smart and creative startups within the smart city model. The research examines medium-sized cities in the Visegrád countries (Czech Republic, Slovakia, Poland, Hungary) with a population ranging from 100,000 to 1 million inhabitants for startups. The research question is: Where are the medium-sized cities in the Visegrád countries that are both startup centers and smart cities? In the course of the research, the term “smart cities” was based on the definition set by the European Commission and the definition of startup centers was made using data analysis of the American Crunchbase database. As a result of the two studies, it can be concluded that there are no cities in the Visegrád countries with an above average level of both startup presence and smart cities.

Open Access: Yes

DOI: 10.3390/smartcities3040070

A Fuzzy Framework for Assessing and Prioritizing Railway Infrastructure Retrofitting against Seismic Hazards – A Case Study

Publication Name: Acta Polytechnica Hungarica

Publication Date: 2025-01-01

Volume: 22

Issue: 4

Page Range: 263-283

Description:

The railway system plays a crucial role in a nation's economy and society, extending beyond mere transportation. In earthquake-prone regions like Razavi Khorasan in Iran, railway infrastructure is highly vulnerable to natural disasters, which can severely disrupt train operations. Ensuring the safety of critical infrastructure, including stations, bridges, tunnels, and railway lines, is essential for maintaining operational integrity and public safety. This study evaluates and prioritizes seismic retrofitting measures for railway infrastructures in Razavi Khorasan. The fuzzy Delphi method is used to gather expert opinions, while the Fuzzy VIKOR method facilitates the prioritization process. Key assessment criteria include seismic intensity potential, vulnerability potential of the zone in terms of distance from the fault, the degree of criticality of the infrastructure in terms of the possibility of continuing transportation operations and the current state of the infrastructure in terms of the state of retrofitting against seismic hazards. The findings reveal critical railway segments that require immediate retrofitting interventions and highlight overall vulnerabilities within the system. This paper underscores the effective application of fuzzy logic methodologies in complex decision making scenarios, offering actionable recommendations to enhance the seismic retrofitting of railway infrastructures.

Open Access: Yes

DOI: 10.12700/APH.22.4.2025.4.16

Validation of a 1D Thermodynamic Simulation of a 4-Cylinder Turbocharged DI Engine with Testbench Measurements †

Publication Name: Engineering Proceedings

Publication Date: 2025-01-01

Volume: 113

Issue: 1

Page Range: Unknown

Description:

This paper presents a one-dimensional (1-D) thermodynamic engine simulation validated through testbench measurements. The objective was to evaluate the accuracy of the 1-D model by comparing simulated results with experimental data from a modern 2-L turbocharged gasoline direct injection (DI) internal combustion engine featuring variable valve timing. Key parameters such as engine speed, air–fuel ratio, temperature, and pressure were measured under controlled conditions. Using AVL BOOST, simulation modeled combustion, valve timing, and thermodynamic processes across intake and exhaust systems. Simulation results were compared with experimental data across various steady-state operating points. The model demonstrated strong agreement with experimental results in steady-state operation. A few differences highlight the need for further refinement of the model. The study confirms the effectiveness of 1-D simulations as a reliable and cost-efficient tool for engine analysis and optimization. Future work will focus on enhancing the accuracy of the simulation.

Open Access: Yes

DOI: 10.3390/engproc2025113023

Modelling biophoton emission kinetics based on the initial intensity value in Helianthus annuus plants exposed to different types of stress

Publication Name: Scientific Reports

Publication Date: 2022-12-01

Volume: 12

Issue: 1

Page Range: Unknown

Description:

Biophoton radiation also referred to as ultra-weak photon emission (UPE) is used to denote a spontaneous and permanent photon emission associated with oxidative processes in cells and seems to universally occur in all living systems as a result of the generation of reactive oxygen species (ROS) that are produced under stress conditions. The measurement of this biophoton emission allows for a non-invasive approach in monitoring phenological stages throughout plant development which has direct relevance in agriculture research. In this study, the emission of photons emanating from sunflower (Helianthus annuus, L.) plants exposed to biotic and abiotic stress has been investigated. In healthy plants raised under controlled growth conditions UPE was low whereas in stressed individuals it considerably increased; particularly upon water stress. The kinetics of the signal is shown to reveal an exponential decay with characteristic dynamics, which appears to reflect different physiological states concomitantly setting in upon stress. The dynamics of the signal decay is shown to vary according to the type of stress applied (biotic vs. abiotic) hence suggesting a putative relationship between the kinetic traits of change in the signal intensity-decay and stress. Intriguingly, the determination of the change in the intensity of biophoton emission that ensued in a short time course was possible by using the initial biophoton emission intensity. The predictability level of the equations demonstrated the applicability of the model in a corroborative manner when employing it in independent UPE-measurements, thus permitting to forecast the intensity change in a very accurate way over a short time course. Our findings allow the notion that albeit stress confers complex and complicated changes on oxidative metabolism in biological systems, the employment of biophoton imaging offers a feasible method making it possible to monitor oxidative processes triggered by stress in a non-invasive and label-free way which has versatile applications especially in precision agriculture.

Open Access: Yes

DOI: 10.1038/s41598-022-06323-3

Stability of Fixed-Point Values in Reduced Fuzzy Cognitive Map Models

Publication Name: Studies in Fuzziness and Soft Computing

Publication Date: 2021-01-01

Volume: 393

Issue: Unknown

Page Range: 359-372

Description:

The authors have already presented their method for reducing oversized FCM models, and also have analyzed the prediction error of the reduced models. These investigations assumed that models have a single fixed-point attractor. The novelty of this paper is that it deals with the stability behavior of the fixed-point attractor value of original-reduced model pairs and compares the number of fixed-point attractors found, the asymptotic values of the concepts, and also checks if any limit cycles or chaotic behavior occur. The method of comparison and also the first results made with two real-life and one synthetic model are presented and some conclusions are taken.

Open Access: Yes

DOI: 10.1007/978-3-030-47124-8_29

Population genetic features of calving interval of the Limousin beef cattle breed in Hungary

Publication Name: Acta Veterinaria Hungarica

Publication Date: 2022-07-06

Volume: 70

Issue: 2

Page Range: 113-120

Description:

Variance, covariance components, heritability, breeding values (BV) and genetic trends in calving interval (CI) of the Limousin population in Hungary were evaluated. A total of 3,008 CI data of 779 cows from three herds in 1996-2016 were processed. For influencing effects GLM method, for population genetic parameters and BV estimation BLUP animal model, for trend analyses linear regression was applied. The average CI obtained was 378.8 ± 3.1 days. The variance distribution components of the phenotype were as follow: age of cow at calving 34.30%, season of calving 26.09%, year of calving 23.00%, sire 7.45%, herd 3.23%, sex of calf 0.33% and type of calving 0.30%. The heritability of CI proved to be low (h2 d = 0.04 ± 0.02 and 0.03 ± 0.02; h2 m = 0.01 ± 0.02). The repeatability was low (R = 0.03 ± 0.02). Based on the phenotypic trend calculation, the CI of cows decreased by an average of 0.60 days per year (R 2 = 0.19; P < 0.05). In case of genetic trend calculation, the average BV of sires in CI increased 0.07 and 0.17 days per year (R 2 = 0.23 and 0.27; P < 0.05).

Open Access: Yes

DOI: 10.1556/004.2022.00008

Characterisation and Modelling of Ultrashort Laser-Driven Electromagnetic Pulses

Publication Name: Scientific Reports

Publication Date: 2020-12-01

Volume: 10

Issue: 1

Page Range: Unknown

Description:

Recent advances on laser technology have enabled the generation of ultrashort (fs) high power (PW) laser systems. For such large scale laser facilities there is an imperative demand for high repetition rate operation in symbiosis with beamlines or end-stations. In such extreme conditions the generation of electromagnetic pulses (EMP) during high intense laser target interaction experiments can tip the scale for the good outcome of the campaign. The EMP effects are several including interference with diagnostic devices and actuators as well as damage of electrical components. The EMP issue is quite known in the picosecond (ps) pulse laser experiments but no systematic study on EMP issues at multi-Joule fs-class lasers has been conducted thus far. In this paper we report the first experimental campaign for EMP-measurements performed at the 200 TW laser system (VEGA 2) at CLPU laser center. EMP pulse energy has been measured as a function of the laser intensity and energy together with other relevant quantities such as (i) the charge of the laser-driven protons and their maximum energy, as well as (ii) the X-ray Kα emission coming from electron interaction inside the target. Analysis of experimental results demonstrate (and confirm) a direct correlation between the measured EMP pulse energy and the laser parameters such as laser intensity and laser energy in the ultrashort pulse duration regime. Numerical FEM (Finite Element Method) simulations of the EMP generated by the target holder system have been performed and the simulations results are shown to be in good agreement with the experimental ones.

Open Access: Yes

DOI: 10.1038/s41598-020-59882-8

DOES TYPE OF CAPITAL MATTER FOR ECONOMIC GROWTH? A STUDY OF THE CHINESE ECONOMY

Publication Name: Investment Management and Financial Innovations

Publication Date: 2025-01-01

Volume: 22

Issue: 1

Page Range: 469-480

Description:

The impact of different types of capital flows on China’s economic growth has been widely studied to determine whether the type of capital significantly affects the Chinese economy. The purpose of this study is to investigate the relationship between long-term capital flows and economic growth in China, considering factors such as Foreign Direct Investment (FDI), portfolio equity, portfolio bonds, and external debt. All secondary data were collected from the World Bank database. The paper also investigates which type of capital flow has the most significant relation with the economic growth of China. A quantitative approach was chosen for the study. Moreover, to overcome the bias output of ordinary least squares, this paper deployed a Two-Stage Least Squares (2SLS) estimation method. This study has found a relatively stable positive relationship between FDI and growth, where the coefficient of 0.9699 indicates that a 1% increase in FDI is associated with a 0.97% growth in Gross Domestic Product (GDP). Similar to FDI, portfolio equity has a positive impact on GDP growth, with a coefficient of 2.1419. In contrast, portfolio bond and debts have a negative coefficient of –1.7752 and –0.2831. These findings contribute to a deeper understanding of China’s development experience, particularly regarding the role of capital flow. The paper explores two key limitations that need to be explored in the future, i.e., the causal relation between each type of long-term capital flow and economic growth, and the impact of COVID-19 on the economic growth relationship.

Open Access: Yes

DOI: 10.21511/imfi.22(1).2025.35