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Comparison of the effects and efficiency of vertical and side tamping methods for ballasted railway tracks

Szabolcs Fischer Ulf Gerber Vitalii Kovalchuk Mykola Sysyn Michał Przybyłowicz

Publication Name: Construction and Building Materials

Publication Date: 2022-01-03

Volume: 314

Issue: Unknown

Page Range: Unknown

Description:

The relatively high maintenance costs of the ballast track are related to the short lifecycle of the ballast layer. The current vertical ballast tamping technology (e.g., Plasser & Theurer, Matisa, etc.) causes high ballast destruction and is neither applicable for unconventional sleepers’ designs nor slab tracks. The side tamping method presents an alternative, ballast saving, and sleeper form independent ballast tamping technology. This paper compares the ballast layer compaction and its resistance to permanent settlements accumulation after the vertical and the side tamping methodologies. Scaled models of ballast layer and tamping units and scaled simulation with discrete element method (DEM) were applied for the comparison. In the laboratory tests, the ballast compaction along the sleeper was estimated using the measurements of elastic wave propagation. The settlements resistance for both tamping methods was estimated under the vibration loading. The tests’ results show 5–7% higher compactness of the ballast layer under the sleeper ends for the side tamping method. The settlement intensity of the ballast layer after the vertical tamping is higher than for the side tamping method. In discrete element modeling, the performed laboratory tests were simulated. The compactness of the ballast bed, as well as the residual stresses, were determined in MATLAB. The side tamping technology provided five times higher residual stresses in the ballast layer below the sleeper than in the case of vertical tamping, which can be explained by the more stable and dense layer resulting from the side tamping ensures higher interlocking between the grains. The simulation of the wave propagation shows an influence of the residual stresses on the wave propagation velocities. The simulated wave propagation velocity was more than two times higher for the side tamping than for the vertical one.

Open Access: Yes

DOI: 10.1016/j.conbuildmat.2021.125708

Trade-offs in warehousing storage location reassignment

Péter Földesi Tamás Bódis Polina Görbe

Publication Name: International Journal of Logistics Systems and Management

Publication Date: 2025-01-01

Volume: 51

Issue: 4

Page Range: 524-538

Description:

In the low-level picker-to-parts warehouses the order picking is the most time- and cost consuming process. The performance indicator for order picking is lead time. The system can be considered efficient if these lead times can be kept low, but this is heavily influenced by the storage location assignment in the warehouse, the routing, and the warehouse layout. The objective of this research is to investigate in what cases and to what extent reassignment and repositioning tasks following efficiency deterioration as well as seek answers to how to minimise these costly tasks and maintain a near-ideal storage location assignment. To solve this problem, an intelligent system concept is presented, which aims to support the warehouse operator in making replenishment decisions, which picking storage to replenish based on the current rotation of item, and which products to repositioning, while maintaining a near ideal storage location assignment. The aim of this paper is to highlight the potential decision points and circumstances, when adaptive storage location reassignment would be necessary and how this concept can help everyday warehouse logistics.

Open Access: Yes

DOI: 10.1504/IJLSM.2025.148067

Virtual Reality in Cerebrovascular Rehabilitation: A Mini Review on Clinical Efficacy and Neurological Impacts

Tamás Haidegger József Tollár Péter Prukner Istvan Drotar Nándor Prontvai Blanka Törő Szilvia Kóra Petra Kós György Wersényi

Publication Name: Acta Polytechnica Hungarica

Publication Date: 2023-01-01

Volume: 20

Issue: 8

Page Range: 321-336

Description:

The application of virtual reality (VR) technology in both upper and lower limb rehabilitation represents a significant advancement in the field of medicine. VR-based therapies provide patients with the opportunity to engage in intensive, repetitive, and targeted exercises that promote neuroplasticity and improve the motor skills necessary for daily life. VR has long been recommended for the rehabilitation of conditions such as in case of ischemic stroke, Parkinson’s disease, and multiple sclerosis, further underscoring its versatility and therapeutic potential. In our study, we evaluated the effectiveness of VR therapy focusing on stroke rehabilitation. The reviewed VR systems provided motion analysis, tracking, feedback reinforcement, and realistic environments to facilitate the restoration of motor functions. Furthermore, we developed a VR-based therapy aimed at both upper and lower limb motor functions, combined with traditional rehabilitation. The application of VR technology not only promotes the improvement of motor functions but also offers economic advantages by reducing the burden on healthcare workers and increasing rehabilitation capacity. Further research is needed to determine the optimal conditions for applying VR therapy in clinical practice.

Open Access: Yes

DOI: 10.12700/APH.20.8.2023.8.17

A work in progress - accreditation of forensic DNA laboratories as a part of the, European Forensic Science Area 2020 (EFSA 2020)” concept

Mónika Nogel Andras Czebe Gabor Kovacs Zsolt Pádár

Publication Name: Forensic Science International Genetics Supplement Series

Publication Date: 2019-12-01

Volume: 7

Issue: 1

Page Range: 836-837

Description:

As 2020 is approaching, various stakeholders and EU Member States are currently implementing some elements of the EFSA2020 concept. EFSA2020 offers Europe the chance to raise the quality level of its forensic science and in doing so, improve the public's confidence in the administration of justice. However, there is plenty of opportunity for further progress in creating the common forensic area. The paper will focus on accreditation of forensic DNA laboratories in V4 countries.

Open Access: Yes

DOI: 10.1016/j.fsigss.2019.10.195

Municipal Household Waste Management Methodologies in the EU Countries: A Reverse Logistics Benchmarking Approach

Edit Süle László Buics Marah Almelhem

Publication Name: Lecture Notes on Multidisciplinary Industrial Engineering

Publication Date: 2025-01-01

Volume: Part F4026

Issue: Unknown

Page Range: 100-109

Description:

Through the application of a reverse logistics benchmark approach, this paper aims to investigate prevailing waste management practices in the European Union (EU) countries. In detail, it will analyze existing waste management practices, identify successful efforts, and identify areas for improvement within the EU region, in order to answer how can different collection waste management practices promote sustainability and integrate with reverse supply network? In this article, a structured literature review is carried out to examine the existing literature background, and public reports are collected and analyzed published by EU nations on waste management. The aim of the article is to understand their current state and evaluate the applicability of reverse logistics techniques in enhancing waste collection, recycling, and disposal. By answering the research question, the examination can provide valuable insights and recommendations for policymakers, as well as those involved in managing waste or stakeholders with an interest in enhancing the sustainability and efficiency of waste management practices in EU countries.

Open Access: Yes

DOI: 10.1007/978-3-031-80330-7_11

Stability of the rubbing phenomenon with the gyroscopic effect

Peter Triesz

Publication Name: Pollack Periodica

Publication Date: 2010-04-01

Volume: 5

Issue: 1

Page Range: 65-72

Description:

The rubbing, as an undesired non-linear dynamical behavior of rotors, is a widely studied topic in the field of rotor-dynamics. Standard models usually use the classic Jeffcott rotor system with several rolling and journal (bearings without rolling elements, usually filled with oil) bearings, or with magnetic ones. The present paper investigates a model that takes into consideration also the gyroscopic effect and its influence on the rubbing phenomenon. © 2010 Akadémiai Kiadó.

Open Access: Yes

DOI: 10.1556/Pollack.5.2010.1.4

Wavelet analysis and finite difference modeling of multiple reflections in transmission lines

A. Bekefi András Fehér Szilvia Nagy

Publication Name: 2nd Middle East Conference on Antennas and Propagation Mecap 2013

Publication Date: 2012-01-01

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

No description provided

Open Access: Yes

DOI: 10.1109/MECAP.2012.6618201

A Comparative Evaluation of Classical and Deep Learning-Based Visual Odometry Methods for Autonomous Vehicle Navigation †

Janos Hollosi Armand Nagy

Publication Name: Engineering Proceedings

Publication Date: 2025-01-01

Volume: 113

Issue: 1

Page Range: Unknown

Description:

This study introduces a comprehensive benchmarking framework for evaluating visual odometry (VO) methods, combining classical, learning-based, and hybrid approaches. We assess 52 configurations—spanning 19 keypoint detectors, 21 descriptors, and 4 matchers—across two widely used benchmark datasets: KITTI and EuRoC. Six key trajectory metrics, including Absolute Trajectory Error (ATE) and Final Displacement Error (FDE), provide a detailed performance comparison under various environmental conditions, such as motion blur, occlusions, and dynamic lighting. Our results highlight the critical role of feature matchers, with the LightGlue–SIFT combination consistently outperforming others across both datasets. Additionally, learning-based matchers can be integrated with classical pipelines, improving robustness without requiring end-to-end training. Hybrid configurations combining classical detectors with learned components offer a balanced trade-off between accuracy, robustness, and computational efficiency, making them suitable for real-world applications in autonomous systems and robotics.

Open Access: Yes

DOI: 10.3390/engproc2025113016

Sustainability and Energy Efficiency in Administrative Processes: A Control Theory Approach with P-graph Optimization

Boglárka Eisingerné Balassa László Buics Boglárka Eisinger

Publication Name: Chemical Engineering Transactions

Publication Date: 2025-01-01

Volume: 120

Issue: Unknown

Page Range: 415-420

Description:

As institutions seek to reduce their environmental impact, administrative processes must be optimized for energy and resource efficiency. This study integrates control theory with P-graph methodology to develop a structured framework for sustainable administrative workflows, focusing on university enrollment systems. P-graph-based optimization identifies minimum-energy pathways and optimal resource configurations, while Model Predictive Control (MPC) and nonlinear control enable real-time process adaptation under dynamic conditions. A Life Cycle Analysis (LCA) compares the carbon footprint of digital and paper-based workflows, evaluating IT infrastructure energy use versus traditional operations. Simulated control strategies support energy-efficient decision-making, highlighting best practices for emission reduction and operational flexibility. The result is a decision-support framework that embeds P-graph into a dynamic control context, guiding control strategy selection to minimize energy use and emissions. This scalable approach supports sustainability-oriented process management across public service domains.

Open Access: Yes

DOI: 10.3303/CET25120070