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

Orsolya 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

Combined Effect of Nano Ferrite and Nano Silica on Properties of Cement Mortar

Rasha R. Rawdhan Azhar J. Bohan Ghaed K. Salman Muhanad Al-Jubouri

Publication Name: International Journal of Integrated Engineering

Publication Date: 2024-01-01

Volume: 16

Issue: 1

Page Range: 350-360

Description:

This study investigates the effects of adding nano-ferrite (N.F.) and nano-silica (N.S.) on the mechanical and biological properties of mortar. By assessing four water-to-cement ratios (1–4%), the ideal nanoparticle doses were determined. Results indicated that both N.F. and N.S. significantly increased the mortar’s strength at ratios between 1% and 4%, while combinations of N.F. and N.S. improved strength up to 3% and 4% substitution, respectively. The mechanisms of strength enhancement were attributed to nanoparticles acting as fillers and hydration accelerators, which densify the mortar microstructure and promote the production of calcium silicate hydrate (C-S-H) gels. In terms of biological properties, the study examined the antibacterial effects of nano-silica and nano-ferrite. Nano-silica demonstrated greater antibacterial potency against all bacterial strains assessed. Both materials exhibited a stronger antibacterial impact on Gram-positive bacteria (Staphylococcus aureus) compared to Gram-negative bacteria (Escherichia coli), due to differences in cell wall structures. The study emphasizes the importance of optimal nanoparticle dosages and identifies limitations that warrant further research, such as durability and potential downsides at higher concentrations. Despite these challenges, the findings underscore the potential of nanoparticles to enhance mortar performance and suggest promising applications in construction and the development of antibacterial materials. Future research should focus on overcoming these constraints and exploring the practical applications of nanoparticle-enhanced mortar in real-world scenarios.

Open Access: Yes

DOI: 10.30880/IJIE.2024.16.01.030

Exploring parental perspectives of childhood speech and language disorders across 10 countries: A pilot qualitative study

Isabel R. Rodriguez-Ortiz Sam Harding Rena Lyons Maja Kelić Kristine M. Jensen de López Inge S. Klatte Marina O. Tomazin Julie Feilberg Sofia Baena Tina C. Mantel Thora S. Ulfsdottir Rama Novogrodsky Krisztina Zajdó

Publication Name: Journal of Speech Language and Hearing Research

Publication Date: 2021-05-01

Volume: 64

Issue: 5

Page Range: 1739-1747

Description:

Purpose: Although researchers have explored parental perspectives of childhood speech and language disorders, most studies have been conducted in English-speaking countries. Little is known about parental experiences across countries, where procedures of language screening and services for language disorders differ. The authors participated in the COST1 Action network IS1406, “Enhancing Children’s Oral Language Skills Across Europe and Beyond,” which provided an opportunity to conduct cross-country qualitative interviews with parents. The aim of this pilot study was to explore ways in which parents construed and described speech and language disorders across countries. Method: Semistructured qualitative interviews were conducted with parents from 10 families in 10 different countries. The data were analyzed using thematic analysis. Findings: The overall theme was “acknowledging parental expertise.” The parents described, in detail, ways in which their children’s speech and language (dis)abilities had an impact on the children’s everyday life. Three subthemes were identified: impairment, disability, and changes over time. Conclusions: The findings suggest that, across a range of countries, parents demonstrated contextualized understandings of their children’s speech and language (dis)abilities, along with the everyday functional implications of the disorders. Hence, despite not holding professional knowledge about language disorders, the voices, views, understandings, and personal experiences of parents in relation to their child’s disorder should be listened to when planning therapy services.

Open Access: Yes

DOI: 10.1044/2020_JSLHR-20-00415

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

Eigenshape based imperfection method for beam-columns with mono-symmetric I-sections

Achim Rubert G. Hajdú

Publication Name: Stahlbau

Publication Date: 2021-08-01

Volume: 90

Issue: 8

Page Range: 600-613

Description:

Eigenshape based imperfection method for beam-columns with mono-symmetric I-sections. This paper shows for the first time the application of the Overall Imperfection Method (OIM) for columns, beams and beam-columns with mono-symmetric I cross-section. The buckling failure mode of compressed members with mono-symmetric I-section is torsional-flexural like. The second-order effect from the rotation around the longitudinal shear axis during the loss of stability is taken into account when the amplitude of the initial imperfection is calculated for the compressed members. For beams, the buckling behaviour is also different from doubly symmetric cross-section because the shear centre and the centre of gravity of the cross-section do not meet at the same position. This paper shows the extension and the usability of the OIM for steel structures with mono-symmetric I-section. The automatic determination of the equivalent amplitudes for columns, beams and beam-columns are presented for the first time. The practicality of the proposed method is demonstrated for single and multi-span members with three examples.

Open Access: Yes

DOI: 10.1002/stab.202100017

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

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