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Publications - 6374

Comparative Seismic Evaluation Across Leading Software: Distinguishing Conventional and Adaptive Pushover Analysis Techniques

O. Kegyes-Brassai Kevin Karanja Kuria

Publication Name: World Conference on Earthquake Engineering Proceedings

Publication Date: 2024-01-01

Volume: 2024

Issue: Unknown

Page Range: Unknown

Description:

The research intends to validate pushover methods through the lens of the incremental dynamic analysis technique. This study will contrast conventional with enhanced pushover strategies, specifically as they are applied to a 2D steel frame, a 3D RC frame, and a reinforced concrete moment-resisting frame structure. For an exhaustive evaluation, state-of-the-art analysis software tools like SAP2000, OpenSees, Etabs, Seismostruct, and AxisVM are to be employed . The aim of the study is to offer insights into how these methodologies fare in predicting the behavior of these structural configurations under varied seismic conditions. Although traditional pushover approaches, such as the Capacity Spectrum Method, Displacement Coefficient Method, and Target Displacement (N2) Method, are appreciated for their simplicity, they also come with inherent limitations. Notably, they tend to overlook the influences of higher modes both horizontally and vertically. To bridge these gaps, the research will explore Adaptive Pushover Analysis (APA), an advanced pushover technique. Given the importance of understanding the seismic behavior of structures, our investigation will focus on how these advanced pushover techniques can be aptly applied to the structural types. We propose an innovative design approach that integrates these advanced pushover analyses with the principles of performance-based seismic design (PBSD). Furthermore, we suggest the inclusion of structural control systems within the realm of pushover analysis. Such systems, engineered to combat external disruptions like seismic events, can significantly mitigate the seismic demands on structures. By modulating the structural response to these external forces, they ensure enhanced safety. Merging these systems with pushover analysis promises a more comprehensive seismic design strategy, making structures more resilient against seismic threats. Once the research concludes, a range of case studies will be deployed to gauge the efficacy of the proposed methodology against traditional pushover tactics. The research's insights will be consolidated and presented in a detailed final report.

Open Access: Yes

DOI: DOI not available

Reversible DC-to-DC converter for a dual voltage automotive system using zero voltage switching technique

Dan V. Nicolae Petre Scortaru Z. Puklus Mihai Cernat

Publication Name: 11th International Conference on Optimization of Electrical and Electronic Equipment Optim 2008

Publication Date: 2008-01-01

Volume: Unknown

Issue: Unknown

Page Range: 251-258

Description:

A novel hysteretic controller for a bi-directional dc-dc converter with ZVS and interleaving for dual voltage systems in automobiles is presented. A variable frequency extended band hysteretic current control method is proposed. In comparison with classical fixed frequency current control PWM, the reverse polarity peak current needed for ZVS operation is kept constant Inductor current ripple decreases with load reduction. Automatic changes in operation between buck and boost modes are accomplished without transient currents. Converter simulations are carried out using Matlab/Simulink platform.

Open Access: Yes

DOI: 10.1109/OPTIM.2008.4602417

Contrasting results and effectiveness of controlled experiments with crowdsourced data in the evaluation of auditory reaction times

Adam Csapo Hunor Nagy Gyorgy Wersenyi

Publication Name: 7th IEEE International Conference on Cognitive Infocommunications Coginfocom 2016 Proceedings

Publication Date: 2017-01-03

Volume: Unknown

Issue: Unknown

Page Range: 421-425

Description:

We developed an application for the Android platform to test reaction times to auditory stimuli on mobile devices. During tests, users were asked to respond as quickly as possible to auditory events provided through headphone playback, and to also identify the directions of those events based on stereo panning. This paper presents a comparative evaluation of data (i.e. response times in seconds and error rates) collected through controlled supervised experiments as opposed to a crowdsourcing based solution. It is demonstrated that in some respects, crowdsourced data and laboratory data show similar results within their own category, but that at the same time a statistical comparison between the two measurement configurations is difficult due to the significant amount of noisy (outlier) data in the crowdsourced case.

Open Access: Yes

DOI: 10.1109/CogInfoCom.2016.7804586

Predictive Repair of Vehicle R1234yf Refrigerant Systems Based on Monitoring of Micro-Leakages

I. Lakatos Jozsef Nagy

Publication Name: Machines

Publication Date: 2026-03-01

Volume: 14

Issue: 3

Page Range: Unknown

Description:

To protect the environment, the R1234yf refrigerant was introduced into the air conditioning systems of modern vehicles. Its price is much higher than that of previous refrigerants, and the gas is slightly flammable, making the prompt detection and repair of even small leaks even more critical. This research aimed to develop a simple, dashboard-based method for serially monitoring and visualizing anomalies in cars after production and before and shortly after delivery. It is possible to infer the presence of minor leaks through online or frequent pressure monitoring after the system has been “resting” (last ignition off for at least 5 h to allow system stabilization: air conditioner vs. outer or engine coolant temperature). Using this method, it can be determined whether the given pressure losses fall within the normal operating range. The essence of the technique is to detect a possible small amount of leakage by monitoring the pressure change (Δp) of the air conditioning system, supported by dashboard(s). The results on the test fleet with 500 cars show that the procedure can be suitable for detecting defects that cause micro-leaks immediately after production. The false-negative detection rate was 0.2, and the false-positive rate was 1.2 at a threshold of ±0.5 bar. Based on a practical example, the method can also be applied to offline cars until the first factory-related claim occurs.

Open Access: Yes

DOI: 10.3390/machines14030268

Measuring of the scalar hysteresis characteristic with a controlled flux density using analog and digital integrators

Tamás Ludvig Miklós Kuczmann Zoltán Pólik

Publication Name: Journal of Electrical Engineering

Publication Date: 2007-08-03

Volume: 58

Issue: 4

Page Range: 236-239

Description:

We have managed to build up a computer controlled system using National Instruments Data Acquisition card and National Instruments LabVIEW software package. First, the specimen under test has been simulated by the Jiles-Atherton model, but simulated measurements have been performed using LabVIEW functions. Our main goal now is to control the magnetic flux density during measurement by using a toroidal core with a feedback controller. In this paper, we show the developed procedure which is suitable for measurement of the hysteresis characteristics using analogue and digital integrators, and to control the waveform of the magnetic flux density determined from the induced voltage of the secondary coil wound on a toroidal core. Our experience is that the developed controller is robust. This work is an initial step to the future work on a vector hysteresis measurement system. © 2007 FEI STU.

Open Access: Yes

DOI: DOI not available

Optical torque sensor development

A. Nagy P. Horváth

Publication Name: Recent Advances in Mechatronics 2008 2009

Publication Date: 2009-01-01

Volume: Unknown

Issue: Unknown

Page Range: 91-96

Description:

The purpose of this study is to develop a contactless torque sensor in the mNm range. The applied optical method is based on the birefringe effect of photoelastic materials. The novelty of the modified reflective photoelastic method is the application of a photoelastic tube as a coupling and measuring element between shafts. Change in intensity of polarized light is proportional to the torque to be measured. Basics of operational principle and practical considerations are also discussed.

Open Access: Yes

DOI: 10.1007/978-3-642-05022-0_16

CONTROLLABILITY OF THE TIME-VARYING FRACTIONAL DYNAMICAL SYSTEMS HAVING MULTIPLE DELYAS IN CONTROL WITH CAPUTO FRACTIONAL DERIVATIVE

Ilker Ozsahin V. Govindaraj Berna Uzun Hijaz Ahmad Taha Radwan K. S. Vishnukumar S. M. Sivalingam

Publication Name: Fractals

Publication Date: 2026-01-01

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

The objective of this study is to analyze controllability results for time-varying linear and nonlinear fractional dynamical systems with multiple control delays within the framework of the Caputo fractional derivative. This paper focuses on examining control problems within a finite time interval, aiming to identify a control function that steers the system’s solution from a specified initial state to a targeted final state. For linear systems, the study establishes necessary and sufficient conditions for controllability by utilizing the Grammian matrix techniques. For nonlinear systems, the existence of a solution is ensured through an iterative technique, with completeness of the space guaranteed. With the help of this technique, we establish the sufficient conditions for the controllability of time-varying nonlinear fractional dynamical systems. The results show that the controllability of fractional dynamical systems can be effectively analyzed with the given framework, along with numerical simulations and graphical representations to clarify the theoretical findings.

Open Access: Yes

DOI: 10.1142/S0218348X26400025

Hydrogen Policy Environment in the European Union, Current Status of Policy Uptake

András Torma Péter Németh Barna Hanula

Publication Name: Chemical Engineering Transactions

Publication Date: 2023-01-01

Volume: 107

Issue: Unknown

Page Range: 499-504

Description:

Hydrogen (H2) can become a crucial technology in building an independent and resilient energy infrastructure. The production and utilisation of green hydrogen will play a crucial role in the energy environment of the European Union in the future. Several strategies were defined, and policy actions were taken. H2 has a comparably high lower heating value and no direct harmful emission during use, so it presents a viable alternative for conventional energy carriers. Independently from the final form of usage, H2 will play a key role in integrating green electricity into the grid, as according to the state-of-the-art, large-scale, long-term energy storage is only feasible in molecules containing H2. H2-based mobility solutions could offer a viable technology for sustainable transportation. This article investigates H2 production and demand in the EU, as well as the directives and incentives of the EU to accelerate H2 production and H2 technologies in general. Based on the existing policies and applications, it reviews the up-to-date status of policy uptake within the EU and gives insights into the different preparedness for the transition to a H2-based energy system of the Member States.

Open Access: Yes

DOI: 10.3303/CET23107084

Mitigating harmful content on social media via platform regulation: The Digital Services Act and content assessment

Gergely Gosztonyi János Tamás Papp Gergely Ferenc Lendvai

Publication Name: Informacios Tarsadalom

Publication Date: 2025-01-01

Volume: 25

Issue: 2

Page Range: 59-72

Description:

The Digital Services Act (DSA) implements a legal framework for digital services, including social media platforms, to ensure that they operate in responsible, accountable ways. With an objective involving three critical theoretical pillars—transparency, accountability, and responsibility—the DSA, among other functions, (mostly) holds online platforms liable for content that they publish and also imposes requirements that they mitigate and remove harmful content. However, from a critical standpoint, the DSA begs some pivotal questions. For one, how can such a legal document, even if binding, mitigate the severe societal, psychological, emotional, and even physical dangers and detriments experienced by victims of social media abuse? For another, how can a supranational regulation combat local disinformation campaigns and political propaganda? In this article, we encourage not only introducing, analyzing, and critically examining the DSA but also propose policy recommendations to ameliorate content moderation on social media platforms.

Open Access: Yes

DOI: 10.22503/inftars.XXV.2025.2.4