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Publications - 6383

Dynamic Analysis of Geosynthetic-reinforced Pile-supported Embankment for a High-Speed Rail

Edina Koch Rashad Alsirawan

Publication Name: Acta Polytechnica Hungarica

Publication Date: 2024-01-01

Volume: 21

Issue: 1

Page Range: 31-50

Description:

Geosynthetic-Reinforced-Pile-Supported (GRPS) embankments are a trustworthy option ideal to support the railways over soft soils. They are widely used for the time-bound infrastructure projects. The majority of earlier research concentrated on the analysis of the GRPS embankments under static loads while the studies on the behavior of these constructions under dynamic loads are scarce. The fundamental purpose of this study has been to better comprehend the dynamic behavior of GRPS embankments in terms of stresses and settlements distribution via 3D modeling employing the finite element method (FEM). The advanced constitutive model of Hardening soil with small-strain stiffness was utilized to simulate the behavior of the soils under dynamic loads and the train load was modeled according to the recommendations of LM71 Eurocode. The results indicate to the contribution of the piles and geosynthetic reinforcement in the decrease of the settlements. The behavior of settlements and stresses under static and dynamic loads is similar. The load efficiency of the piles decreases during the passage of the train remarkably. The train speed affects obviously on the behavior of the GRPS embankment.

Open Access: Yes

DOI: 10.12700/APH.21.1.2024.1.3

Prediction of fullerene stability using topological descriptors

Eniko Bitay Tamás Réti

Publication Name: Materials Science Forum

Publication Date: 2007-01-01

Volume: 537-538

Issue: Unknown

Page Range: 439-448

Description:

In recent years, several attempts have been made to characterize the geometric structure of fullerenes by means of topological shape factors in order to predict their physical properties and stability. In this paper, we present a simple method to estimate the stability of fullerenes on the basis of quantitative topological criteria. This approach is based on the concept of the generalized combinatorial curvatures defined on the set of simple graphs embedded on a closed surface without boundary (sphere, torus, projective plane, Klein bottle). It is shown that starting with the computed generalized combinatorial curvatures several novel topological indices can be generated. From computations performed on a set of C40 and C60 fullerenes, we concluded that the four topological shape factors tested (Λ(-1), Ω(-1), Λ(1) and Ω(1)) could be successfully used to preselect the most stable fullerene isomers.

Open Access: Yes

DOI: 10.4028/0-87849-426-x.439

A CROSS-COUNTRY STUDY ON THE DETERMINANTS OF WORKING CAPITAL MANAGEMENT: GMM APPROACH

Laszlo Vasa Simona Andreea Apostu Ploypailin Kijkasiwat Anwar Hussain

Publication Name: Transformations in Business and Economics

Publication Date: 2022-01-01

Volume: 21

Issue: 3

Page Range: 288-305

Description:

The paper analyzed the determinants of Working Capital Management (WCM) of listed manufacturing firms across South Asian Association of Regional Corporation (SAARC) countries from 2000 to 2020. Employing a Generalized Method of Moments, we found that operational risk and market risk are key hurdles to efficient working capital management. Our results are providing an important managerial implication for the use of operational risk and market risk in selected countries. Firms in selected countries can manage an optimal level of WCM through controlling operational risk and market risk, therefore should develop a ranking system about WCM activities to boost up their firm value.

Open Access: Yes

DOI: DOI not available

A Fuzzy Driven Framework for the Cognitive Modeling and Quantitative Analysis of Aggregated Avatars

Adam Csapo György Persa

Publication Name: IEEE Joint 22nd International Symposium on Computational Intelligence and Informatics and 8th International Conference on Recent Achievements in Mechatronics Automation Computer Science and Robotics Cinti Macro 2022 Proceedings

Publication Date: 2022-01-01

Volume: Unknown

Issue: Unknown

Page Range: 143-150

Description:

In this paper, our goal is to motivate the structured design and quantitative analysis of a class of avatars which we refer to as (fuzzy) aggregated avatars. Following a brief overview of the different avatar types based on the literature, we formulate a newly proposed definition of aggregated avatars, and also extend this concept with the more specialized class of fuzzy aggregated avatars. Further, we propose a framework to facilitate the design and experimental analysis of fuzzy aggregated avatars, and describe a use-case example in which user interaction patterns within a 3D virtual reality space are mapped onto dynamic avatar behaviors.

Open Access: Yes

DOI: 10.1109/CINTI-MACRo57952.2022.10029574

Effect of Non-conventional Seating Position on Driver Injuries in the Case of a Self-driving Car

I. Lakatos Laszlo Porkolab

Publication Name: Lecture Notes in Mechanical Engineering

Publication Date: 2023-01-01

Volume: Unknown

Issue: Unknown

Page Range: 35-49

Description:

Today the automotive industry is making great strides toward driverless driving. Vehicle manufacturers, as well as well-known development service providers, have already developed a large number of concepts and design studies for fully automatic vehicles. In the future, there will be no more limits to driverless driving. However, a fully autonomous vehicle must also protect its occupants in the event of an accident. The driver becomes a passenger, no longer having to take part in driving the vehicle. The big challenge for the future is how the seat that can be rotated in the front row of a car will have an impact on the future passenger safety system. The aim of the research is to build a simulation model that will allow us to study the area. It is absolutely necessary to use a real test to validate the simulations. To investigate the influence of swivel seats on the restraint systems, the seat positions to be analyzed must first be narrowed down. The area examined extends from 0˚, which corresponds to the current driver’s seat position, to the 180˚ position, in which the driver’s view is directed towards the rear. In order to limit the number of variants that are examined, the angle steps are limited. As part of this research, the 0˚, 30˚, 60˚, 90˚, 135˚, 180˚ positions of the seat are examined in more detail and examinations are carried out on the basis of these variants.

Open Access: Yes

DOI: 10.1007/978-3-031-15211-5_4

Probabilistic occupancy grid map building for Neobotix MP500 robot

Claudiu Radu Pozna Erno Horváth

Publication Name: Proceedings of the 2016 13th Workshop on Positioning Navigation and Communication Wpnc 2016

Publication Date: 2017-01-17

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

In vehicle and robot navigation low-level tasks such as path planning, obstacle avoidance and autonomous operation are extensively studied nowadays. Most of these task require map building. In this paper a map representation is discussed with the focus for the singular domain of our Neobotix MP500 mobile robot. Among others the state of the art map building techniques will be introduced such as topological map, line map, landmark-based map and of course in more detail the occupancy grid based map. The probabilistic representation of the occupancy grid will be examined as a map building problem for the given mobile robot.

Open Access: Yes

DOI: 10.1109/WPNC.2016.7822843

Structured learning for extraction of daily life log measured by smart phone sensors

János Botzheim Naoyuki Kubota

Publication Name: Smart Innovation Systems and Technologies

Publication Date: 2015-01-01

Volume: 30

Issue: Unknown

Page Range: 277-293

Description:

This chapter deals with producing information using structured learning to extract daily life log measured by smart phone sensors. Acceleration, angular velocity, and movement distance are measured by smart phone sensors and stored as the entries of the daily life log together with the activity information and timestamp.First, this chapter introduces the concept of Informationally Structured Space (ISS) and explains how smart phones can be used for collecting data for the daily life log. Then, structured learning is proposed for estimating the human activities based on the time series of the measured data. The method applies growing neural gas for performing clustering on the data, and spiking neural network for estimating the activity. A modified simple spike response model is applied to reduce the computational cost. The external input values of the spiking neurons depend on the growing neurons, and various metrics are investigated in the input calculation.Experiments are performed for verifying the effectiveness of the proposed method. Finally, the future direction on this research is discussed.

Open Access: Yes

DOI: 10.1007/978-3-319-13545-8_16

The Political Elite's Thematic Framing of China in Recent Central European Elections

László Csicsmann Jan Hornat Joanna Starzyk-Sulejewska

Publication Name: Issues and Studies

Publication Date: 2023-03-01

Volume: 59

Issue: 1

Page Range: Unknown

Description:

China is geographically distant from Central European states, but cultural, economic and political exchanges between the regions are increasing. As such, the perception of China in these societies is susceptible to frames and narratives that are either instrumentally or organically created by local political elites. This paper aims to scrutinize the narratives and frames employed in the Czech Republic, Hungary and Poland during their most recent election cycles. It identifies five basic types of frames employed in the selected countries: sovereignty, opportunity, the balance of trade, debt-traps and human rights. This paper then concludes by evaluating these thematic frames and summarizes the key similarities in public discourses concerning relations with China.

Open Access: Yes

DOI: 10.1142/S1013251123500029

Examination and development of a radio frequency inductor

Miklós Kuczmann Zoltán Pólik

Publication Name: Przeglad Elektrotechniczny

Publication Date: 2008-12-01

Volume: 84

Issue: 12

Page Range: 230-233

Description:

Nowadays, inductors can be found in almost every electrical and electronic product. These key components are needed to store electrical energy, select frequencies, and protect againist overvoltage and overcurrent. In the case of the inductors, which usually work in the range of radio frequency, the one of the most important attributes is the quality factor. The aim of the project is to increase the Q-factor of an RF SMT inductor and to favour the industrial research and development about inductors by using the finite element method.

Open Access: Yes

DOI: DOI not available