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Found 6423 publications

On the temperature rate dependent transformation processes

Lino Costa Imre Czinege Imre Felde Tamás Réti Rafael Colas

Publication Name: Materials Science Forum

Publication Date: 2007-01-01

Volume: 537-538

Issue: Unknown

Page Range: 571-578

Description:

Kinetic models of new types are suggested which are designated primarily to predict the progress of non-isothermal transformations occurring during rapid heating and cooling in alloys. A common feature of each model outlined is that it takes into account not only the varying temperature but also the rate of temperature change on the transformation rate of the process. The two models represented by differential equations are generated by using the concept of virtual kinetic parameters, which can be determined from non-isothermal experiments only. A key property of the virtual parameter "p" involved in the transformation rate equations is that it quantitatively characterizes the temperature rate dependence of the non-isothermal reaction.

Open Access: Yes

DOI: 10.4028/0-87849-426-x.571

Application of the localized method of fundamental solutions to heat transfer problems

Csaba Gáspár

Publication Name: Journal of Physics Conference Series

Publication Date: 2024-01-01

Volume: 2766

Issue: 1

Page Range: Unknown

Description:

A localized version of the Method of Fundamental Solutions is applied to the 2D steady heat transfer equation with spatially varying thermal conductivity. Though the corresponding fundamental solution cannot be computed in general, the localization splits the original problem into several subproblems defined on small subdomains; in these subdomains, the subproblems are approximately converted to certain convection-diffusion equations with constant coefficients, so that the Method of Fundamental Solutions is applicable. In each subdomain, the corresponding subproblem is solved separately. This results in an iterative method, which mimics the overlapping (alternating) Schwarz method. Due to its advantageous numerical properties, the technique seems a useful generalization of the Method of Fundamental Solutions. The method is illustrated through numerical examples.

Open Access: Yes

DOI: 10.1088/1742-6596/2766/1/012157

Burnout syndrome among healthcare professionals of neonatal intensive care units

Mihály Dió Ibolya Lipienné Krémer Ágnes Harmath Zsuzsanna Soósné Kiss

Publication Name: Orvosi Hetilap

Publication Date: 2022-08-07

Volume: 163

Issue: 32

Page Range: 1268-1274

Description:

Introduction: Burnout syndrome among healthcare workers is a well-known problem. Its occurrence and the roots have been addressed in several studies. The daily work of the specialist employees in the neonatal intensive care units is extremely stressful physically and mentally. Objective: The study assessed the frequency and intensity of burnout phenomenon among healthcare professionals working in neonatal intensive care units and examined the relations between institutional levels, occupation, and work experience. Method: Data were collected in 2019 using the Maslach Burnout Inventory (MBI) questionnaire compiled by Maslach and Jackson. Results: In the field of examined dimensions of burnout syndrome, the most characteristic was emotional exhaustion, which has occurred with a frequency of nearly 30% and with typically high intensity among professionals working in neonatal intensive care units (N = 278). In addition, one-fifth were characterized by a high frequency and intensity of depersonalization. At the same time, nearly a third of them experienced a decrease in personal effectiveness. Work¬place and time spent in healthcare did not show a significant connection with the incidence of burnout syndrome, however, burnout syndrome occurred with a higher frequency and intensity among those working in level III. neo¬natal intensive care unit. Conclusion: This is the first comprehensive burnout survey among premature and new born intensive care units in Hungary. Knowing the consequences of burnout syndrome, it is important to prevent and recognize symptoms as early as possible.

Open Access: Yes

DOI: 10.1556/650.2022.32539

Rapid fleet condition analysis through correlating basic vehicle tracking data with engine oil ft-ir spectra

Charlotte Besser Péter Raffai András Lajos Nagy Bettina Ronai Adam Agocs J. Rohde-Brandenburger Nicole Dörr

Publication Name: Lubricants

Publication Date: 2021-12-01

Volume: 9

Issue: 12

Page Range: Unknown

Description:

Engine oil condition and tribological performance are strongly interrelated. Accordingly, oil condition monitoring is common in various applications. This is especially important, as oil condition depends on the fueling and utilization profile of an internal combustion engine. Common practice involves the measurement of various parameters, such as the total acid number and total base number, oxidation, nitration, viscosity, and elemental composition; thus, it can be time-consuming and resource-intensive. This study provides a methodology for rapid analysis for large vehicle fleets or sample sizes, using only Fourier-transformed infrared spectroscopy and the subsequent multivariate data analysis offers a rapid alternative to commonly available methods. The described method provides a rapid, cost-efficient, and intuitive approach to uncovering differences in the oil condition. Furthermore, understanding the underlying reasons in engine construction and the resulting chemical degradation is also possible.

Open Access: Yes

DOI: 10.3390/lubricants9120114

Realization of the Jiles-Atherton hysteresis model applying the LabVIEW and MATLAB software package

Miklós Kuczmann Eszter Sárospataki

Publication Name: Journal of Electrical Engineering

Publication Date: 2006-12-01

Volume: 57

Issue: 8 SUPPL

Page Range: 40-43

Description:

In this paper we will show a procedure developed under MATLAB and LabVIEW software package which is able to simulate the scalar ferromagnetic hysteresis applying the Jiles-Atherton model. The MATLAB realization has been developed to analyze the behaviour of model, the LabVIEW realization has been applied to simulate a toroidal shape core. The measurement system containing the core will be the basis of a controlling algorithm to realize sinusoidal form of the magnetic flux density. © 2006 FEI STU.

Open Access: Yes

DOI: DOI not available

A new planning instrument for urban development in Hungary: The modern cities program

Dávid Fekete

Publication Name: Regional Science Policy and Practice

Publication Date: 2022-08-01

Volume: 14

Issue: 4

Page Range: 740-758

Description:

Urban development has gained increasing momentum in governmental development policies of the past few decades throughout the Central and Eastern European region. Analyzing a new instrument of Hungarian spatial policy (Modern Cities Program), the paper shows a new initiative of a Central and Eastern European country in the field of urban development. The analysis shows the role of the program in European and domestic regional development policy, its impact on financing infrastructural developments in Hungarian urban areas, and the structure of the projects of the Modern Cities Program. Due to its sizable budget and philosophy, the Modern Cities Program is clearly unrivaled by development programs of the past century of Hungarian regional development. The program with its philosophical grounding in the still not defunct French étatist, dirigiste tradition typical of the 1960s shows a number of similarities to the latter in terms of its applied tools and methods, such as the system of planning contracts, centralized financing, and decision-making. Conversely, there is no evidence to support the interpretation of the program as a novel urban development regime, as underlined by the absence of widespread social involvement in the conceptualization of development objectives. Economic development is at the forefront of the program, with industrial and economic development-related measures affecting each participating city.

Open Access: Yes

DOI: 10.1111/rsp3.12422

Extended Measurement Methods for Onboard Detection of Brake Disc Deformation †

István Lakatos Péter Ori

Publication Name: Engineering Proceedings

Publication Date: 2025-01-01

Volume: 113

Issue: 1

Page Range: Unknown

Description:

Runout is a common failure of brake discs. The detection of this fault usually depends on the driver, as there is a vibration in the car and on the brake pedal. As Advanced Driver Assistant Systems are implemented and autonomous driving modes are available, braking is carried out by the car instead. Brake disc runout can cause longer braking distance, so it is essential to recognize and repair it. NVH measurements have been validated to be one of the solutions to detect the fault immediately without disassembling the brake unit. In this article, the previous vibration measurements are extended with other methods that can also be used for fault detection. Brake fluid pressure measurement and integration of the disc rotation angle sensor enable the detection of faults without additional sensors. The aim of the research is to design a measurement method that can be compared with previously validated measurements.

Open Access: Yes

DOI: 10.3390/engproc2025113078

Capacitive and hybrid energy storages for metro railcars

Istvan Szenasy

Publication Name: 2013 IEEE International Electric Vehicle Conference Ievc 2013

Publication Date: 2013-12-01

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

In this paper the simulation models by Matlab for an urban-metro railcar and some newer methods for reducing the need value of capacitance for energy storage are presented. The achievable decreasing ratio of the needed energy storage at SCAP is 25 to 40 % with this improved energy control method. It was been investigated the supercapacitor and the Li-ion battery as hybrid energy storage system and its effectiveness under operation of a suitable energy control system. Mass reduction of our hybrid storage system is significant. © 2013 IEEE.

Open Access: Yes

DOI: 10.1109/IEVC.2013.6681139

On the accuracy of general method adapted in EN 1993-1-1

G. Hajdú F. Papp

Publication Name: Journal of Constructional Steel Research

Publication Date: 2022-08-01

Volume: 195

Issue: Unknown

Page Range: Unknown

Description:

In this paper, a safety assessment of the General Method (GM) in Eurocode 1993–1-1:2005 is carried out. The GM covers the stability verification of steel structures subjected to compression and/or bending even in cases where the structures have irregular shape, complex load and support conditions. Several research papers dealt with the accuracy of the GM, but within the method, all of them used the Ayrton–Perry formula type standard reduction factors calibrated for the fundamental (flexural and lateral-torsional) buckling modes. These studies compared the results of the GM to the results of the geometrically and materially nonlinear analysis with imperfections (GMNIA) applying characteristic numerical models. In this paper, firstly the exact imperfection factors of fundamental buckling modes are calculated with GMNIA, after that these factors are used within the GM. This way the effect of the inaccuracy of the standard calibrations is excluded, and the real accuracy of the GM will be reflected in the results. This study covers the fundamental case of coupled flexural and lateral-torsional buckling modes in case of hot-rolled IPE and H-type cross-sections.

Open Access: Yes

DOI: 10.1016/j.jcsr.2022.107354