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Found 6334 publications

Heat Characteristics and Emission Effect of a Fuel-operated Auxiliary Air Heater Fed with Fuel E10, E30 and E100

Ibolya Zsoldos György Szabados Péter Nagy

Publication Name: Periodica Polytechnica Mechanical Engineering

Publication Date: 2024-01-01

Volume: 68

Issue: 2

Page Range: 181-186

Description:

In order to increase the comfort of vehicle passengers in specific vehicle categories, the heating of the passenger compartment is not provided by the heat from the engine driving the vehicle but by an additional heating device. The study examines the effect of auxiliary heaters that use liquid fuels to heat the passenger compartment of vehicles. The device was operated during the test with two different mixtures containing bioethanol (E30, E100) and the original motor gasoline (E10). It aimed to understand the effects of different fuels, particularly heating performance, operating time and emissions. Based on the results, as the ethanol content increases, the temperature of the device’s flame and heating air decreases. The experiments showed that in the case of E100 bioethanol, the average temperature measured in stable operating conditions was significantly lower than in the case of E10 motor gasoline. That suggests that an increase in the ethanol content reduces the heating performance. Another significant result of the study was that in the case of mixtures containing ethanol, a longer operating time is required to achieve the same amount of heat, which leads to additional fuel consumption. In addition, when using E100 bioethanol, the amount of harmful gases that are emitted increases significantly during the longer operating time. This observation can be important for evaluating the environmental impact and efficiency of vehicles.

Open Access: Yes

DOI: 10.3311/PPme.36911

Position sensorless extended and unscented Kalman filters with permanent magnet flux linkage and load torque estimation for surface-mounted PMSM

Krisztian Horvath

Publication Name: Automatika

Publication Date: 2024-01-01

Volume: 65

Issue: 3

Page Range: 1201-1212

Description:

In this paper, novel position sensorless state estimators with improved robustness to permanent magnet (PM) flux linkage variations in permanent magnet synchronous machines (PMSMs) are presented. Unlike state estimators using conventional infinite inertia or electromechanical models, the estimators presented here can also estimate the PM flux linkage, so they are not sensitive to its uncertainty. For each models used for state estimation, a detailed observability study is presented. Due to the nonlinear models, extended and unscented Kalman filter algorithms are used for the implementation. To compare the sensitivity of conventional and proposed state estimators to uncertainty in electrical parameters, numerical simulations are carried out. In addition, the computational burden of the estimators is compared by real-time execution.

Open Access: Yes

DOI: 10.1080/00051144.2024.2354643

Health labor force exodus: A systematic review of drivers influencing nurses’ migration intentions from source countries

Koltai Judit Petra Esther Amofa-Adade

Publication Name: Journal of Infrastructure Policy and Development

Publication Date: 2024-01-01

Volume: 8

Issue: 11

Page Range: Unknown

Description:

The global shortage of nurses has resulted in the demand for their services across different jurisdictions causing migration from developing to developed regions. This study aimed to review the literature on drivers of nurses’ migration intentions from source countries and offer future research directions. A search strategy was applied to ScienceDirect, Web of Science, and Scopus academic databases to find literature. The search was limited to peer-reviewed, empirical studies published in English from 2013–2023 resulting in 841 papers. The study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines to conduct a systematic review of 35 studies after thorough inclusion and exclusion criteria. In addition, the VOSviewer software was utilized to map network visualization of keywords, geographic and author cooperation for bibliometric understanding. The findings revealed various socio-economic, organizational, and national factors driving nurses’ migration intentions. However, limited studies have been conducted on family income, organizational culture, leadership style, infrastructure development, social benefits, emergency service delivery, specialized training, and bilateral agreements as potential drivers for informing nurses’ migration intentions. Moreover, a few studies were examined from a theoretical perspective, mainly the push and pull theory of migration. This paper contributes to the health human resources literature and shows the need for future studies to consider the gaps identified in the management and policy direction of nurse labor migration.

Open Access: Yes

DOI: 10.24294/jipd.v8i11.8400

Driving Strategy Optimization in Experimental Electric Vehicles: A Study on Optimization Algorithms †

Zoltan Pusztai Ferenc Szauter Ferenc Friedler

Publication Name: Engineering Proceedings

Publication Date: 2024-01-01

Volume: 79

Issue: 1

Page Range: Unknown

Description:

In this paper, the driving strategy simulations for a single-seat, lightweight, energy-efficient experimental electric vehicle are introduced. The vehicle’s operation is simulated using a developed measurement-based vehicle model in the simulation environment. The optimization was performed for the UniTrack platform at the ZalaZone proving ground using the algorithms Particle Swarm Optimization (PSO) and Genetic Algorithm (GA), with different optimization settings corresponding to varying iterations and initial population/swarm sizes. A 2.95% difference was observed between the least effective and the best PSO results, where both the number of iterations and swarm size were doubled. This demonstrates the effectiveness of PSO in solving the presented driving strategy problem, even when using fewer iterations and a smaller swarm size.

Open Access: Yes

DOI: 10.3390/engproc2024079042

Companies Local Embeddedness and Culture: A Review

Zsuzsanna Pálffy

Publication Name: Economic Research Guardian

Publication Date: 2024-01-01

Volume: 14

Issue: 2

Page Range: 73-87

Description:

The criticism of neoclassical economic behaviour, the changing company-space dynamics, the effects of globalization, and the cultural turn have stimulated new trends in social sciences. In recent decades, the concept of embeddedness has evolved significantly and now holds a solid place in regional economics and economic geography; however, interdisciplinary studies remain common. This review article examines the interaction between corporate embeddedness and culture, aiming to demonstrate how previous research has interpreted culture's role in embeddedness. A comprehensive literature analysis, the primary question addressed is how corporate practices and cultural norms develop in a specific socio-cultural context. The review's novelty lies in its dual approach to culture's role in embeddedness. On one hand, it explores the value and norm system of embeddedness, focusing on culture's role in limiting social practices. On the other hand, it discusses culture's role in the interactions of the embedding process at all levels of embeddedness and culture. The literature indicates that the culture of both the company and the receiving space – including trust levels, openness, willingness to settle, and receptiveness – determines the success of embeddedness.

Open Access: Yes

DOI: DOI not available

Investigation of the spatial concentration of companies in the agglomeration settlements of Győr, 2022

Petra Kecskés Anikó Tompos Patrícia Horváth

Publication Name: Teruleti Statisztika

Publication Date: 2024-01-01

Volume: 64

Issue: 4

Page Range: 515-540

Description:

When making installation decisions, companies take into account a complex system of criteria, which includes the agglomeration area, as well as the presence of companies performing the same or similar activities. The purpose of this research is to examine the spatial distribution of companies established in the agglomeration settlements of Győr. In the course of the analysis, map tests were carried out and a quadratic analysis was prepared. The results of the research show that there is a high degree of spatial concentration of companies in the Győr agglomeration area, and territorial densification can also be seen based on settlement-level indicators.

Open Access: Yes

DOI: 10.15196/TS640405

Assisting the passage of heavy vehicles, increasing traffic safety designing traffic lights and urban lighting in a smart city

Nikolett Fecser

Publication Name: International Journal of Heavy Vehicle Systems

Publication Date: 2024-01-01

Volume: 31

Issue: 4

Page Range: 562-578

Description:

Congestions caused by traffic bottlenecks or accidents have become commonplace. The consequences are delays, as well as environmental, health and economic damage. One of the solutions to the problem is to expand transport infrastructures and to apply and develop advanced control systems, as well as to create a public lighting network for new traffic routes and pavements. The capacity of the road section examined in this study is inadequate during peak hours, and significant queues are formed. Turning in a wide angle from the secondary direction to the left, especially with heavy vehicles is difficult and involves a risk of accidents. Due to heavy traffic, the intersection is to be controlled by traffic lights. In this study, the implementation of a traffic-engineering plan of a junction situated in Győr is presented with phase-timing plans. In the second part of the study, the results of measurements are described.

Open Access: Yes

DOI: 10.1504/IJHVS.2024.139695

OWA operators in the insurance industry

István A. Harmati David Fulep Koppány Krisztián Norbert Kovács

Publication Name: Journal of Infrastructure Policy and Development

Publication Date: 2024-01-01

Volume: 8

Issue: 13

Page Range: Unknown

Description:

In this paper, we examine a possible application of ordered weighted average (OWA for short) aggregation operators in the insurance industry. Aggregation operators are essential tools in decision-making when a single value is needed instead of a couple of features. Information aggregation necessarily leads to information loss, at least to a specific extent. Whether we concentrate on extreme values or middle terms, there can be cases when the most important piece of the puzzle is missing. Although the simple or weighted mean considers all the values there is a drawback: the values get the same weight regardless of their magnitude. One possible solution to this issue is the application of the so-called Ordered Weighted Averaging (OWA) operators. This is a broad class of aggregation methods, including the previously mentioned average as a special case. Moreover, using a proper parameter (the so-called orness) one can express the risk awareness of the decision-maker. Using real-life statistical data, we provide a simple model of the decision-making process of insurance companies. The model offers a decision-supporting tool for companies.

Open Access: Yes

DOI: 10.24294/jipd8015

Opportunities of VR for Teaching History

Attila Pongracz Balint Lampert Csaba Sándor Horváth

Publication Name: Acta Polytechnica Hungarica

Publication Date: 2024-01-01

Volume: 21

Issue: 3

Page Range: 143-162

Description:

The present study examines the opportunities of VR in the context of humanities and arts and – within their frameworks – in that, of history. Its novelty clearly lies in the fact that in this fields’ cyberspace is not used either by public or by higher education. The inclusion of info-communication tools for history teaching, does not really follow the current trajectory of development. Educators usually work according to methods that have become the most common and familiar. This research clearly revealed that students, who regularly use the VR space, in a History course of teacher training, consider it experiential, user-friendly, simple, problem-oriented and thus, easier to visualize historical facts. The regular and widespread use of VR software could greatly and easily help to progress the historical curriculum space.

Open Access: Yes

DOI: 10.12700/APH.21.3.2024.3.10