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Publications - 6374

Fuzzy based hierarchical performance evaluation in telecommunications access networks

Ferenc Lilik Ĺaszĺo T. Ḱoczy

Publication Name: 2014 International Conference on Humanoid Nanotechnology Information Technology Communication and Control Environment and Management Hnicem 2014 7th Hnicem 2014 Joint with 6th International Symposium on Computational Intelligence and Intelligent Informatics Co Located with 10th Erdt Conference

Publication Date: 2014-01-01

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

Performance evaluation of wire pairs of telecommunications access networks is a great challenge for telecommunications service providers. Although there are existing methods and systems for it, these are expensive or unpunctual. This paper presents a novel, hierarchical fuzzy inference based performance evaluation method for wire pairs of access networks, which is based on measurements of the pairs. The set of antecedent (input) parameters and their role in the evaluation, the consequent (output) states and the type of the used fuzzy rule bases are presented. In addition, the behavior and the role of the noise that can be measured in the wire pairs are detailed.

Open Access: Yes

DOI: 10.1109/HNICEM.2014.7016242

Adaptation of Life Form Categorisation of Ellenberg and Mueller-Dombois to the Hungarian Flora

D. Bartha B. A. Lukács I. Dancza G. Pinke Z. Botta-Dukát

Publication Name: Acta Botanica Hungarica

Publication Date: 2023-04-25

Volume: 65

Issue: 1-2

Page Range: 1-34

Description:

The categorisation of plant species according to their life form has a long history in plant ecology. The most popular system worldwide and also in Hungary is Raunkiaer's categorisation according to the position of buds (meristems) surviving the adverse season. The original system contains only seven categories, resulting in high diversity within each category. Therefore, different refinements are suggested. This paper aims to apply an internationally accepted refinement of Raunkiaer's categorisation, the Ellenberg and Mueller-Dombois system, to the Hungarian flora.

Open Access: Yes

DOI: 10.1556/034.65.2023.1-2.1

Method of fundamental solutions formulations for biharmonic problems

Andreas Karageorghis Csaba Gáspár

Publication Name: Engineering Analysis with Boundary Elements

Publication Date: 2025-06-01

Volume: 175

Issue: Unknown

Page Range: Unknown

Description:

We consider various method of fundamental solution (MFS) formulations for the numerical solution of two-dimensional boundary value problems (BVPs) governed by the homogeneous biharmonic equation. The motivation for employing the proposed techniques comes from the corresponding boundary integral representations. These are carefully analyzed in the case the domain of the BVP under consideration is a disk. The results of this analysis detect a potentially troublesome case in one of the proposed MFS approaches. Numerical results confirm the analytical findings for more general domains.

Open Access: Yes

DOI: 10.1016/j.enganabound.2025.106180

Simulations of poroelastic materials in a complex acoustic system using frequency-dependent parameters in the mid-frequency range

Dániel Feszty Janos Kun

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:

Efficiency requirements prompt manufacturers to develop ever lighter acoustic packages in vehicles. Poroelastic materials are essential to achieve the desired interior noise level targets and thus the simulation of their effects is of utmost importance in NVH analyses. However, it is challenging to achieve good validation between finite element method (FEM) based simulation results and measurements in the mid-frequency range (400-1000 Hz). One possible reason could be the lack of using frequency-dependent Biot-paremeters describing the poroelastic materials (PEM) characteristics of trims. The present research aims to employ frequency-dependent Biot-parameters for the PEM materials to investigate the acoustic response of a scaled car-like steel structure composed of flat plates and U-section stiffeners enclosing an air cavity. Porous acoustic material is applied to the walls of the cavity. The focus of the study is to understand the effect of applying frequency-dependent Young's modulus and damping values for the PEM parameters in the 100-1000 Hz range. Simulation results obtained from ESI VPS FEM solver are compared with measurements, with particular focus on the interior sound pressure levels. The simulation methodology, including discretization techniques, structural damping and fluid damping applications are described in detail.

Open Access: Yes

DOI: 10.3397/IN-2021-2869

Optically controlled microstrip transmission line for slow wave propagation

Renu Sharma Raghbendra Singh Tomar Ruchika Mehta Hijaz Ahmad

Publication Name: International Journal of Modern Physics C

Publication Date: 2026-01-01

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

This paper investigates the utilization of optical control in diverse planar devices, focusing on the Metal-Insulator-Semiconductor (MIS) microstrip transmission line on a semiconductor substrate as a specific example. Optical illumination induces intriguing e®ects in this structure, wherein the metal layer can serve as a transparent conductive oxide when illuminated. The MIS interconnect, crucial in modern high-speed Very Large-Scale Integration (VLSI) circuits, has undergone extensive scrutiny regarding Electromagnetic (EM) wave behavior using various analytical approaches. Controlling wave propagation and manipulating MIS-type planar transmission lines enable the design of delay lines, phase shifters, filters, etc. Energy dissipation in MIS-layer-type transmission lines is also explored due to its significant impact on interconnect design. This paper employs theoretical and experimental models to analyze MIS line characteristics and performance. Optical control presents opportunities to enhance planar device functionality and e±ciency, particularly in MIS microstrip transmission lines, driving advancements in high-speed VLSI circuits and fostering innovative applications across industries.

Open Access: Yes

DOI: 10.1142/S0129183127500422

Benchmark Analysis of Plastic Strain-Based Lifetime Estimation Fatigue Models in Aspect of SMD Component Standoff Height

Ambrus Zelei Antal Bakonyi

Publication Name: Advances in Transdisciplinary Engineering

Publication Date: 2024-01-01

Volume: 59

Issue: Unknown

Page Range: 128-134

Description:

Thermomechanical fatigue is one of the most common cause of the failure in microelectronic technology in the solder joints. The lifetime prediction for microelectronic components is a very important area in nowadays automotive industry, because the lifetime estimation fatigue models in the literature differ in their results by orders of magnitude. However, developing an accurate lifetime estimation methodology for microelectronic components is not straightforward, because the failure mechanism of the solder joints under cyclic thermomechanical load is not fully understood. In addition, there are numerous tolerances and uncertainties during the designing and manufacturing processes, such as component size, copper pad area, solder material volume or the formed standoff height of the component from the copper pad. These parameters can hugely affect the lifetime of the solder joint. In this paper a benchmark analysis based on finite element method were carried out with four plastic strain-based fatigue models to understand the impact of the standoff height to the estimated lifetimes. Three CAD models were created with identical parameters, except the standoff height of the components. Creating the solder geometries for the 3D models, Surface Evolver software were used. The result shows that the fatigue models give the same tendencies varying the standoff height values. However, changing the standoff height increases the differences between models, even if they are tuned so that the estimated lifetime matches for a certain standoff height.

Open Access: Yes

DOI: 10.3233/ATDE240536

The effect of reduced bee pollination period to the fruit set of apricots

I. Skóla L. Szalay P. Benedek Z. Erdos J. Nyéki

Publication Name: Acta Horticulturae

Publication Date: 2006-01-01

Volume: 701 II

Issue: Unknown

Page Range: 723-726

Description:

The duration of effective bee pollination period was limited by caging flowering branches for shorter or longer time. In the case of self-fertile apricots even a partial limitation of the effective duration of bee pollination period significantly reduced the fruit set and the yield. This is because pollen dehiscence of anthers and the receptive period of stigmas do not overlap in time within the individual flowers. Accordingly, additional bee pollination (moving bee colonies to the orchards at blooming period) is needed to get a profitable yield when bee visitation of plantations is not abundant enough for some reasons.

Open Access: Yes

DOI: 10.17660/ActaHortic.2006.701.129

Bibliometric mapping of brand activism: trends, themes, and trajectories

Anees Ahmad Anil Kumar Md Billal Hossain

Publication Name: International Review on Public and Nonprofit Marketing

Publication Date: 2026-06-01

Volume: 23

Issue: 2

Page Range: 449-477

Description:

The concept of brand activism has recently emerged as a distinct phenomenon, garnering increasing scholarly interest. However, research in this area is still in its infancy, characterized by fragmented studies and a lack of cohesive theoretical frameworks. This review aims to analyze the prevailing research patterns in brand activism by classifying the essential attributes of publications. Using specified search criteria, the Scopus database was used to find, extract, select, and review relevant publications from 1984 to 2025. In the search, 259 publications were selected for this study after application of the exclusion and inclusion criteria. This bibliometric analysis is based on performance analysis and science mapping. The results reveal the most influential papers, authors, journals, and nations in this study area. The findings suggest that brand activism research is multidisciplinary, encompassing business ethics, psychology, public policy, management, and marketing. The study identified six thematic clusters: Corporate Political Advocacy and Institutional Change; Consumer Ethical Responses and Brand-Directed Activism; Societal Impact of Brand Activism; Market–Society Tensions in Brand Activism; Moral Emotional Responses to Brand Activism; Authenticity, Credibility, and Competitive Outcomes of Brand Advocacy. These themes highlight their applications, ranging from directing corporate political advocacy and stakeholder alignment on socio-political issues to enhancing authenticity, credibility, and the competitive outcomes of brand activism. The implications of this research emphasize brand activism as a strategic approach that links corporate values to societal requirements to create social change in an increasingly polarized marketplace. This study is novel in presenting a comprehensive bibliometric and science-mapping of brand activism research to date, providing key takeaways, outlining future research directions, and motivating scholars to explore this phenomenon further.

Open Access: Yes

DOI: 10.1007/s12208-026-00473-0

Laboratory Investigation on Seams between Rails and Hardened Fine-grained, as well as Hadfield Steel Plates with Manual Arc Welding

Szabolcs Fischer Szabolcs Szalai András Brautigam Nikoletta Légmán

Publication Name: Acta Polytechnica Hungarica

Publication Date: 2025-01-01

Volume: 22

Issue: 4

Page Range: 83-102

Description:

In the last decade, hardened fine-grained plate components have been used in turnouts and crossings on Western European urban rail networks, as well as in Hungary, in place of traditional rail or Hadfield steel components. The first crossing was built in Hungary in 2016. These components have many advantages, such as the ease with which they can be machined in the factory; they are less prone to cracking than rails due to their block design (high load-bearing cross-section); however, their weldability to rails and lifetime repairability present numerous challenges for railway turnout manufacturers and operators. There have been numerous studies on joint and repair welding of rails and hardened finegrained materials, but there is little or no information available on joint welding with manual arc welding of these two different materials. The current study aims to investigate the welds of coated electrode manual arc welding of rails (R260 and R400 HT) and hardened finegrained plates (in this case, Hardox 500) under non-laboratory conditions while strictly adhering to technological specifications, in comparison to manual arc welding of rails and Hadfield steels. Laboratory tests included raw material chemical composition, macroscopic tests, micro-hardness measurements, tensile, shear, and bending tests.

Open Access: Yes

DOI: 10.12700/APH.22.4.2025.4.6