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Resilience-oriented seismic retrofit of heritage masonry minarets using hybrid base isolation and supplemental damping

Said Elias Mustafa Ergun Zeliha Tonyali Adnan Kiral

Publication Name: Structures

Publication Date: 2026-01-01

Volume: 83

Issue: Unknown

Page Range: Unknown

Description:

Historic masonry mosques represent a highly vulnerable class of cultural heritage structures whose seismic fragility stems from their complex geometries, heterogeneous material composition, and rigid load-transfer mechanisms. This study presents a resilience-oriented seismic performance improvement of the historic masonry minaret of the Bayburt Grand Mosque, a structure with limited lateral deformation capacity that challenges the applicability of conventional strengthening measures. To address this limitation, a hybrid retrofitting strategy is introduced, integrating lead rubber bearings (LRBs) with supplemental viscous dampers (VDs) at the foundation level. This combined system—implemented for the first time in a historic masonry minaret—aims to enhance energy dissipation and displacement control through a minimally invasive and architecturally compatible approach. Finite element analyses (FEA), coupled with MATLAB-supported optimization routines, were used to calibrate isolator stiffness and damper coefficients. Three configurations were evaluated: fixed-base, LRB-isolated, and hybrid LRB–VD systems. Nonlinear time-history analyses (NTHAs) using the 1992 Erzincan (Otlukbeli) earthquake record quantified displacements, stress–strain responses, and damage progression. Results show that while base isolation mitigates seismic demand, it remains insufficient under restricted deformation capacity. The proposed hybrid system reduces peak horizontal displacements from 22 cm to 12 cm, limits drift ratios below 0.17 %, and lowers maximum tensile stresses from 4.890 MPa to 0.490 MPa—well below the masonry tensile strength of 0.880 MPa. Two iterative analytical design methodologies are additionally introduced to derive effective isolator stiffness and viscous damping coefficients, enabling systematic integration into resilience-focused evaluation frameworks. Overall, the study advances reliability-based, conservation-compatible retrofitting practices for historic masonry minarets and supports sustainable strategies for seismic risk mitigation.

Open Access: Yes

DOI: 10.1016/j.istruc.2025.110893

The role of driver's eye height in the design of crest curves of roads

Dániel Miletics Khalil Khaska

Publication Name: Pollack Periodica

Publication Date: 2023-09-25

Volume: 18

Issue: 3

Page Range: 113-118

Description:

The driver's eye height from the ground, as what drivers can see on the road, is essential for their safety and for avoiding road hazards. Using the statistical analysis of vehicles sample, the statistical parameters of the measured set of values were determined. A one-sample t-test was done to check whether the measured sample differs from the driver's eye height value specified in the Hungarian design guidelines. A new range of driver's eye height has been found, which is considered an update to the current value and might be applied in the upcoming road design. Parallel with the eye-height analysis, sight distances at vertical crest curves were modeled by AutoCAD Civil 3D. The minimum radiuses of the crest curves were defined for human eye height and for sensors of autonomous vehicles.

Open Access: Yes

DOI: 10.1556/606.2023.00808

FACTORS EFFECTING FEMALE STARTUPPERS IN HUNGARY

Márta Konczos Szombathelyi Petra Kinga Kézai

Publication Name: Economics and Sociology

Publication Date: 2021-01-01

Volume: 14

Issue: 4

Page Range: 186-203

Description:

The present paper focuses on female startup founders in Hungary. Numerous studies examine female entrepreneurship, but the topic of female startups is a less explored area. The research was carried out in two stages: at first in 2019 through an online survey and in-depth interviews, and then in May 2021 with in-depth interviews due to the delays caused by the COVID-19 pandemic. Mixed research methodology was used and comprised of an online questionnaire administered in startup-themed closed social media groups (n=113) and in-depth interviews among experts and members of the ecosystem (n=7+7). The aim was to conclude how potential female startup founders could be encouraged and what form of support should be given to them, as well as to explore the effects of the Covid-19 pandemic on female startup entrepreneurs. The results show that 70 percent of respondents have their own business, these were set up by both sexes between the ages of 24 and 35. The respondents mostly use equity when starting their businesses. Although the proportion of women among startup founders is very low, a positive entrepreneurial attitude can be observed among them. The startup ecosystem is centralised in Hungary; it is only emerging in some major university cities outside the capital. The strengthening role of startup communities and social media is unquestionable. Furthermore, the results reveal limiting factors, especially complex ones hindering female start-ups, which can typically be traced back to family and social reasons. To overcome these obstacles governments should continue facilitating startup development. The pandemic was considered as an opportunity to promote new ideas and features, concentrate on design and finetune their startup businesses.

Open Access: Yes

DOI: 10.14254/2071-789X.2021/14-4/11

Steering System Modification for Autonomous Test Vehicles and the Measurement of Steering Geometry †

Zoltan Pusztai László Illés Orova Máté Kapocsi

Publication Name: Engineering Proceedings

Publication Date: 2025-01-01

Volume: 113

Issue: 1

Page Range: Unknown

Description:

This study presents the development and implementation of an electronically actuated steering system in a Formula Student Driverless race car, aiming to support autonomous driving capability. A DC motor with a belt-drive mechanism was integrated into the original steering rack assembly without altering its core mechanical characteristics. The research also includes a validation of the steering geometry using both physical measurements and CAD simulations. The objective of this measurement is to determine the steering angle as a function of the steering wheel input angle, ensuring that the resulting data accurately informs vehicle dynamics models such as the kinematic bicycle model. These steps form the basis for closed-loop control integration in the autonomous driving platform.

Open Access: Yes

DOI: 10.3390/engproc2025113067

Welding distortion generated uncertainties in the vibrational behavior of a ladder-like structure

Dániel Feszty Marcell Treszkai David Sipos

Publication Name: Proceedings of Inter Noise 2021 2021 International Congress and Exposition of Noise Control Engineering

Publication Date: 2021-01-01

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

Recent developments in acoustic simulation methods allowed engineers to assess the vibroacoustic behavior of various type of structures within a virtual environment, thus allowing the replacement of prototype-based development with simulations. However, there are some factors, that cannot be considered in simulations in advance. In the present study, the effect of the distortions generated due to welding on a ladder-like structure equipped with flat plates was investigated. The measured acceleration frequency response functions were compared to finite element simulation results. The measured responses differed significantly from the simulation, even in the low frequency ranges, where the global modes were not expected to be altered or vanished. Investigation of the simulated results revealed that the additional modes were related to the vibration of the plates, which were assumed to be flat, instead of considering the warping caused by the welding process. After measuring the approximate deformation of the plates, an updated simulation model was made, introducing an approximate curvature in them. The results obtained with the updated simulation model performed much better in the low frequency range as well as in the third octave-averaged frequency bands up 1200 Hz. The sensitivity of the warping was also systematically evaluated.

Open Access: Yes

DOI: 10.3397/IN-2021-2844

The cognitive entity generation: Emergent properties in social cognition

László Imre Komlósi Patrick Waldbuesser

Publication Name: 6th IEEE Conference on Cognitive Infocommunications Coginfocom 2015 Proceedings

Publication Date: 2016-01-25

Volume: Unknown

Issue: Unknown

Page Range: 439-442

Description:

The paper identifies the characteristics of the post Y-Generation in relation to information processing and knowledge management in order to support the growing awareness of the digital age and the assumption that socialization and acculturation in the digital era rests on a significant paradigm change in the realm of social cognition. Digital culture is claimed to be acquired by the members of modern societies in a smooth and seamless way the result of which is the permeability between human agents and non-human agents in the contexts of information processing and communicative interaction. The fuzzy borderlines within the digital environment are deemed to result in parallel manner of knowledge management as opposed to the traditionally constituted manner of linear processing. The paper elucidates the process in which traditional cultural narratives get fragmented while the members of the community get profoundly engaged in digital social environments to provide for a cognitive net of augmented virtual realities. The paper draws attention to parallel tendencies in the study of social cognition and points at a direction that necessitates a novel perception of digital culture and digital literacy.

Open Access: Yes

DOI: 10.1109/CogInfoCom.2015.7390633

Analysis of temporal patterns of physiological parameters

Balázs Benyó

Publication Name: Neural Networks in Healthcare Potential and Challenges

Publication Date: 2006-12-01

Volume: Unknown

Issue: Unknown

Page Range: 284-316

Description:

This chapter deals with the analysis of spontaneous changes occurring in two physiological parameters: the cerebral blood flow and respiration. Oscillation of the cerebral blood flow is a common feature in several physiological or pathophysiological states and may significantly influence the metabolic state of the brain. Our goal was to characterize the temporal blood flow pattern before, during, and after the development of CBF oscillations. Investigation of this phenomenon may not only clarify the underlying regulatory mechanisms and their alterations under certain conditions but also lead to the development of novel clinical diagnostic tools for early identification of developing cerebrovascular dysfunction in pathophysiological states such as brain trauma or stroke. A disturbance in normal breathing may occur in several nervous and physical diseases. In the present study, we introduce a reliable online method which is able to recognize abnormal sections of respiration, that is, the most common breathing disorder, the sleep apnea syndrome, based on a single time signal, the nasal air flow. There are several common features of the above problems and signals under investigation that imply similar solutions. The chapter introduces the systematic way of selecting proper feature extraction method and optimal classification procedure. The introduced approach can be generalized for the analysis of similar time series featuring physiological parameters. © 2006, Idea Group Inc.

Open Access: Yes

DOI: 10.4018/978-1-59140-848-2.ch013

Effect of junction type on the vibroacoustic response of a system of plates

Dániel Feszty Marcell Treszkai

Publication Name: Proceedings of Inter Noise 2021 2021 International Congress and Exposition of Noise Control Engineering

Publication Date: 2021-01-01

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

Modelling of junctions is one of the most challenging tasks in vibroacoustics, especially for Statistical Energy Analysis (SEA), where the results heavily depend on the damping (DLF) and coupling loss factors (CLF). Also, it is an interesting question to determine that to what extent does the DLF or CLF contribute to the overall vibroacoustic characteristics of a structure? The aim of this paper is to investigate via measurements and SEA simulations the effect of the ratio of DLF and CLF on the response of a system for various junctions, such as riveting, bolting, line and point welding, between two steel plates. Loss matrices are determined experimentally by the Power Injection Method in the 200-1600 Hz frequency range. The simulation was performed in the ESI VA One software by using its analytical CLF formulations and compared to experimental data. For the reference case, a bended plate structure was considered, representing an ideal junction between two subsystems. This was equipped with damping foils to ensure the same weight and then compared to the results from other joints. Results showed that increasing the CLF could be more effective than focusing on increasing the DLF.

Open Access: Yes

DOI: 10.3397/IN-2021-2565

On the differences of the discrete weak and strong maximum principles for elliptic operators

Miklós E. Mincsovics Tamás L. Horváth

Publication Name: Lecture Notes in Computer Science Including Subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics

Publication Date: 2012-06-06

Volume: 7116 LNCS

Issue: Unknown

Page Range: 614-621

Description:

When choosing a numerical method to approximate the solution of a continuous mathematical problem, we need to consider which method results in an approximation that is not only close to the solution of the original problem, but possesses the important qualitative properties of the original problem, too. For linear elliptic problems the main qualitative properties are the various maximum principles. The preservation of the weak maximum principle was extensively investigated in the last decades, but not the strong maximum principle preservation. In this paper we focus on the latter property by giving its necessary and sufficient conditions, investigating the relation of the preservation of the strong and weak maximum principles and illustrating the differences between them with numerous examples. © 2012 Springer-Verlag.

Open Access: Yes

DOI: 10.1007/978-3-642-29843-1_70