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Found 6273 publications

Development of atomic beam probe for tokamaks

M. Berta G. Anda I. G. Kiss J. Havlicek Sz Tulipán P. Hacek M. Aradi Cs Buday G. Veres S. Zoletnik A. Bencze

Publication Name: Fusion Engineering and Design

Publication Date: 2013-11-01

Volume: 88

Issue: 11

Page Range: 2875-2880

Description:

The concept and development of a new detection method for light alkali ions stemming from diagnostic beams installed on medium size tokamak is described. The method allows us the simultaneous measurement of plasma density fluctuations and fast variations in poloidal magnetic field, therefore one can infer the fast changes in edge plasma current. The concept has been worked out and the whole design process has been done at Wigner RCP. The test detector with appropriate mechanics and electronics is already installed on COMPASS tokamak. General ion trajectory calculation code (ABPIons) has also been developed. Detailed calculations show the possibility of reconstruction of edge plasma current density profile changes with high temporal resolution, and the possibility of density profile reconstruction with better spatial resolution compared to standard Li-BES measurement, this is important for pedestal studies. © 2013 Elsevier B.V.

Open Access: Yes

DOI: 10.1016/j.fusengdes.2013.05.064

Combustion and Emission Analyses of a Diesel Engine Running on Blends with Methanol

Justas Žaglinskis Kristóf Lukács György Szabados Ákos Bereczky

Publication Name: Energy Environment and Sustainability

Publication Date: 2021-01-01

Volume: Unknown

Issue: Unknown

Page Range: 141-172

Description:

The ambient air around us is continuously and increasingly loaded and polluted through emission that comes from different sectors, especially from the transportation sector. This fact is due to the growing energy consumption in the transport sector which is forecasted worldwide in the nearer and far future. Bio-based energy may be consumed in an increasing way in the sector until 2050. Methanol, and if it is produced on bio-basis, called bio-methanol, is the simplest alcohol. Methanol costs less than other automotive alternative alcohols, for example, ethanol or butanol, so it may be among the cheapest technical alcohols. As for methanol’s structure, it contains 30% more inherent oxygen on a molecular base than fossil diesel. The aim of this research is to give comprehensive overview about the methanol’s effect on the combustion and emission properties of a diesel engine. During the analyses of combustion and emission characteristics the most relevant parameters have been included. The study also contains calculations regarding theoretical combustion (oxidation process) of the different hydrogen-carbons. A rarely investigated parameter, O2 consumption or demand is also in focus, besides CO2 emission and intensity throughout the calculations. For our experimental test series, diesel fuel was the base fuel and it has been mixed with biodiesel first, and this mixture has been further blended with methanol. Methanol’s theoretical contribution to the diesel–biodiesel blend’s O2 consumption and CO2 emission is a small amount. Engine’s external parameters have not changed significantly if it is running on blend with methanol. Methanol has rather affected the combustion and emission properties of the engine more significantly.

Open Access: Yes

DOI: 10.1007/978-981-16-1280-0_6

Assembly Line Overall Equipment Effectiveness (OEE) Prediction from Human Estimation to Supervised Machine Learning

János Jósvai Péter Dobra

Publication Name: Journal of Manufacturing and Materials Processing

Publication Date: 2022-06-01

Volume: 6

Issue: 3

Page Range: Unknown

Description:

Nowadays, in the domain of production logistics, one of the most complex planning processes is the accurate forecasting of production and assembly efficiency. In industrial companies, Overall Equipment Effectiveness (OEE) is one of the most common used efficiency measures at semi-automatic assembly lines. Proper estimation supports the right use of resources and more accurate and cost-effective delivery to the customers. This paper presents the prediction of OEE by comparing human prediction with one of the techniques of supervised machine learning through a real-life example. In addition to descriptive statistics, takt time-based decision trees are applied and the target-oriented OEE prediction model is presented. This concept takes into account recent data and assembly line targets with different weights. Using the model, the value of OEE can be predicted with an accuracy of within 1% on a weekly basis, four weeks in advance.

Open Access: Yes

DOI: 10.3390/jmmp6030059

Modelling OCB and CWB by combined Fuzzy Signature model

Dalia Susniene Daiva Žostautienė Ojaras Purvinis László T. Kóczy

Publication Name: Economic Research Ekonomska Istrazivanja

Publication Date: 2021-01-01

Volume: 34

Issue: 1

Page Range: 1546-1565

Description:

Globalization and its challenges for organizations led to the understanding that employees can be a critical factor contributing to the organization’s performance. Therefore, various studies sought to understand employee’s behaviour that in itself encompasses various forms of engagement. One of the constructs defining engagement is citizenship behaviour (OCB) and counterproductive work behaviour (CWB). Based on previous researches, the study aims to contribute to the knowledge on the correlation between OCB and CWB considered as a behavioural engagement, from one side, and interplay of these constructs with the related constructs such as a trait engagement, perception of organization, state engagement, from another side. Since the empirical studies typically tend to concentrate on one or several factors separately, it is difficult to get a better understanding of relationship of all forms of engagement in corpore. To address this gap, we create a complex model of investigation developed to describe the linkage of the factors - OCB, CWB and related constructs under one umbrella and, by employing a combined statistical and Fuzzy Signature (FSig) model, we investigated the link with behavioural engagement. The present study covered one region of the northern part of Lithuania. It is based on 144 completed questionnaires from 35 companies. Findings support the assumption of the relationships of behavioural engagement (i.e. OCB and CWB) and the remaining multifaceted factors, and make a step forward by offering a new model for investigation the multifaceted phenomenon of employee engagement.

Open Access: Yes

DOI: 10.1080/1331677X.2020.1844581

Comprehensive Efficiency Analysis of Ethanol–Gasoline Blends in Spark Ignition Engines

I. Szabó Gábor Nagy Zaid Tharwat Mursi Anna Wégerer

Publication Name: Eng

Publication Date: 2025-10-01

Volume: 6

Issue: 10

Page Range: Unknown

Description:

This paper investigates the effects of using 10% v/v (E10) and 30% v/v (E30) ethanol–gasoline blends on spark ignition (SI) engine fuel consumption, brake-specific fuel consumption, brake thermal efficiency, combustion parameters and exhaust gas temperature. The 30% v/v ethanol–gasoline blend was designed not to exceed the octane number (RON and MON) of the regular commercially available reference fuel (E10); therefore, the knock resistance of the reference and research fuel does not differ significantly. The tests were conducted on an AVL internal combustion engine test cell using a four-stroke, four-cylinder, turbocharged SI engine with direct injection and a compression ratio of 12.2:1. The engine was manufactured in 2022, and it is the latest commercially available version currently in production. Engine tests were conducted under stoichiometric conditions (when possible) at loads ranging from 2–20 bar brake mean effective pressure and engine speeds ranging from 1000–6000 rpm, and the fuel consumption, brake-specific fuel consumption, combustion parameters, exhaust gas temperature and brake thermal efficiency were measured using the two different ethanol–gasoline blends. Test results showed that the higher concentration ethanol–gasoline blend—due to its lower density, lower heating value and higher latent heat of vaporization—had increased fuel consumption, brake-specific fuel consumption and decreased brake thermal efficiency, while exhaust gas temperature also decreased (at 2500 rpm 12 bar BMEP, the differences were 11%, 6.6%, −0.78% and −3.7%, respectively). Peak combustion pressures were identical under the same operating conditions, but the peak combustion temperature of E30 was on average 3% lower.

Open Access: Yes

DOI: 10.3390/eng6100256

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

János Hollósi 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

Chinese and Indian transnational corporations’ investments in Hungary

Katalin Völgyi

Publication Name: Statisztikai Szemle

Publication Date: 2021-01-01

Volume: 99

Issue: 3

Page Range: 266-287

Description:

The aim of this paper is to assess the main features of Chinese and Indian investments in Hungary and the role of the Hungarian Government’s Eastern Opening policy in the attraction of investments from these two Asian giants. This paper covers the sectoral distribution, modes of market entry and motivations of Chinese and Indian foreign direct investments. The automotive sector is the most attractive sector for investors from both countries. ICT manufacturing (electronics) and services and the renewable energy sector are also very attractive for Chinese companies. The same is true for IT/BPO services and the chemical sector in the case of Indian companies. Chinese and Indian companies enter the Hungarian economy mainly through green-field investments or acquisitions. Market-seeking and strategic asset-seeking motives are dominant in the case of investors from both countries. In the last decade, the Eastern Opening policy has positively influenced the investment decision (location choice) of several new Chinese and Indian investors and the further expansion of investments by Chinese and Indian companies located in Hungary.

Open Access: Yes

DOI: 10.20311/stat2021.3.hu0266

A meshless polyharmonic-type boundary interpolation method for solving boundary integral equations

Csaba Gáspár

Publication Name: Engineering Analysis with Boundary Elements

Publication Date: 2004-01-01

Volume: 28

Issue: 10 SPEC. ISS.

Page Range: 1207-1216

Description:

A boundary interpolation technique is introduced based on multi-elliptic partial differential equations. The interpolation problem is converted to a special higher order partial differential equation which is completely independent of the geometry of the original problem. Based on this interpolation method, meshless methods are constructed for the 2D Laplace-Poisson equation. The presented approach makes it possible to avoid solving large and dense interpolation equations. The auxiliary higher order partial differential equation is solved by robust, quadtree-based multi-level methods. The results can be easily generalized to 3D problems as well. © 2004 Elsevier Ltd. All rights reserved.

Open Access: Yes

DOI: 10.1016/j.enganabound.2003.04.001

Replacing Traditional Transmission Models with Artificial Intelligence †

Cs Tóth-Nagy Tamás Koller

Publication Name: Engineering Proceedings

Publication Date: 2025-01-01

Volume: 113

Issue: 1

Page Range: Unknown

Description:

The development of vehicle simulation models is becoming increasingly important, especially for the virtual validation of new automotive features. New methods are emerging that need to be tested and validated to ensure their proper functioning. The use of artificial intelligence methods can accelerate product development processes, so it is essential for companies to examine the applicability of these solutions. This article compares the results of a traditional rule-based transmission model and an artificial intelligence-based transmission model against real vehicle measurements. Creating a transmission model using the new artificial intelligence-based method requires less time and effort than developing a rule-based model. However, experimental data is required to train the model. This paper addresses the challenges of artificial intelligence-based transmission modeling and highlights the new advantages of artificial intelligence-based solutions.

Open Access: Yes

DOI: 10.3390/engproc2025113061