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Found 6289 publications

Artificial aging experiments of neat and contaminated engine oil samples

Ibolya Zsoldos András Lajos Nagy J. Rohde-Brandenburger

Publication Name: Lubricants

Publication Date: 2021-06-01

Volume: 9

Issue: 6

Page Range: Unknown

Description:

This study highlights how the results from an artificial engine oil aging method compare to used engine oil samples collected from a vehicle fleet. Additionally, this paper presents the effect of contaminating the oil during aging with synthetic fuel alternatives on the physical and chemical properties of artificially aged engine oil samples. A laboratory-scale artificial thermo-oxidative aging experiment was conducted on multiple samples of commercially available formulated fully-synthetic SAE 0W-30 engine oil. The goal of the experiment was to establish the validity of the artificially aged samples as well as the validity of the underlying process in reproducibly fabricating small batches of aged engine oil with comparable chemical and physical properties to real-life used oils. Eight samples were subjected to distinct load cases (temperature, air flow rate, sample volume and aging time). Six additional samples were subjected to an intermediate load case, with five of them contaminated with selected conventional fuels and novel automotive fuel candidates. Conventional oil analysis was conducted on each sample to determine oxidation, residual additive content, kinematic viscosity and total base number. Additionally, analysis results were compared to in-use engine oil samples through PCA. The resulting oil condition after aging is in accordance with independently published results in terms of zinc dialkyldithiophosphate content and kinematic viscosity. Contaminated aging with OME3-5 resulted in a drop in antioxidant content and elevated kinematic viscosity. Based on the comparison with in-use samples, artificial aging of 200 mL engine oil at 180◦ C with 1 L/min air flow for 96 h can produce similar oil conditions as mixed vehicle use for 7000 km.

Open Access: Yes

DOI: 10.3390/lubricants9060063

Study of the antifungal effect of a copper-containing foliar fertilizer

Balázs Ásványi Renato Kalocsai E. Lakatos Viktoria Vona Tamás Szakál Zsolt Giczi

Publication Name: Cereal Research Communications

Publication Date: 2021-06-01

Volume: 49

Issue: 2

Page Range: 337-341

Description:

Winter wheat (Triticum aestivum L.) is one of the most important arable crops. Copper-containing fertilizers are used in crop production to treat or reduce the negative effects of copper deficiency. Various copper compounds are also widely used as effective fungicide agents. The influence of a copper-containing foliar fertilizer prepared from a copper solution and sucrose had been tested on the yield and raw protein content of winter wheat in previous field experiments. In this work, we studied the antifungal effect of this particular foliar fertilizer in an in vitro trial, wherein the fungicide effect on growth and reproduction of specific plant pathogens, i.e., Fusarium graminearum and Drechslera sorokiniana, was evaluated with the agar well diffusion method. The results showed that doses of the foliar fertilizer corresponding to field applications of at least 1 kg ha−1 had antifungal effects, which were significant (P < 0.01) above the concentration level of 3337 mg L−1, corresponding to 2 kg ha−1 application, against both fungal pathogens. A linear correlation (r2 > 0.95) was found between copper concentration and fungicide efficiency in the concentration range studied. The fungicide efficiency of the foliar fertilizer was lower than that of the commercially available copper-oxychloride fungicide. The sole use of the foliar nutrient tested probably cannot replace fungicide treatments. However, in addition to its plant nutrition effect, its antifungal properties should also be taken into consideration.

Open Access: Yes

DOI: 10.1007/s42976-020-00108-y

Current use and future perspectives of spatial audio technologies in electronic travel aids

Runar Unnthorsson Michal Bujacz Alin Moldoveanu Simone Spagnol Marcelo Herrera Martinez Oana Bslan György Wersényi

Publication Name: Wireless Communications and Mobile Computing

Publication Date: 2018-01-01

Volume: 2018

Issue: Unknown

Page Range: Unknown

Description:

Electronic travel aids (ETAs) have been in focus since technology allowed designing relatively small, light, and mobile devices for assisting the visually impaired. Since visually impaired persons rely on spatial audio cues as their primary sense of orientation, providing an accurate virtual auditory representation of the environment is essential. This paper gives an overview of the current state of spatial audio technologies that can be incorporated in ETAs, with a focus on user requirements. Most currently available ETAs either fail to address user requirements or underestimate the potential of spatial sound itself, which may explain, among other reasons, why no single ETA has gained a widespread acceptance in the blind community.We believe there is ample space for applying the technologies presented in this paper, with the aim of progressively bridging the gap between accessibility and accuracy of spatial audio in ETAs.

Open Access: Yes

DOI: 10.1155/2018/3918284

Fractal and structural entropy calculations on the epitaxially grown fulleren structures with the help of image processing

Péter Turmezei Ákos Nemcsics Imre Mojzes Szilvia Nagy

Publication Name: Sisy 2009 7th International Symposium on Intelligent Systems and Informatics

Publication Date: 2009-12-01

Volume: Unknown

Issue: Unknown

Page Range: 65-67

Description:

Molecular beam epitaxially grown fullerene layers are investigated with the help of image processing. The layered structures are studied in morphological respect. The individual layer morphologies are derived from the atomic force microscopy picture of the surface. The pattern morphology of the certain layers is analysed by box counting method. The surface morphology shows fractal behaviour. The pattern of each layer shows different dimension. The actual dimension depends on the actual distance of the layer from the substrate. The change of the dimension is attributed to the change of the binding behaviour. The topology of the surface is also studied using participation ratio and structural entropy calculations. © 2009 IEEE.

Open Access: Yes

DOI: 10.1109/SISY.2009.5291194

The protection of genetic resources in the intersection of biological diversity and intellectual property rights

Barna Arnold Keserű

Publication Name: Rechtskultur

Publication Date: 2024-01-01

Volume: Unknown

Issue: Unknown

Page Range: 339-351

Description:

Diversity is a key component of sustainable development. This stems from the systems theory approach, as a diverse system adapts best to environmental change. From this perspective, diversity is a guarantee of survival, and it serves as a tool of fighting for food security. The complexity and diversity must therefore be protected. One endpoint of diversity is biological and genetic diversity, while the other endpoint is cultural diversity. The protection of biological diversity is linked to the protection of genetic resources. The issues of the protectability of genetic resources is a new direction in intellectual property law, with the declared aim of promoting aspects of sustainable development. There are new, emerging legal institutions at international level which are not yet part of the universal system of intellectual property rights and it is up to international legislation to make them so. A key step was the adoption of the WIPO Treaty in this field in May of 2024. The purpose of this paper is to analyze the current and future possibilities for protection.

Open Access: Yes

DOI: DOI not available

Effect of ethical leadership on emotional labor: evidence from Nigerian fast-food restaurant sector

Adel Ahmed Esther Ugo Alum Mohammad Fakhrul Islam Friday Ogbu Edeh Muhamad Mustafa Mundu

Publication Name: Journal of Human Resources in Hospitality and Tourism

Publication Date: 2025-01-01

Volume: 24

Issue: 4

Page Range: 721-741

Description:

The enthronement of ethical leadership typology to enhance employee positive work behavior in the fast-food restaurant sector has generated serious debate amongst scholars and practitioners. To provide answers to the above, this research adopted a cross-sectional survey design with a population of one hundred and ninety-eight participants drawn from twenty selected fast-food restaurants sector, in south-eastern Nigeria. Social learning theory and social exchange theory were employed as the underpinning theories of the study. The study’s results demonstrated that ethical leadership dimensionalities predicted the measures of emotional labor. The research concludes that ethical leadership enhances employees’ positive emotional work behavior in the fast-food restaurant sector. One of the practical implications of this study is the prioritization of ethical leadership as an instrument to boost performance in the workplace through emotional labor by HR managers and the owners of fast-food businesses.

Open Access: Yes

DOI: 10.1080/15332845.2025.2531598

Opinion of the hungarian population on the reform of beverage packaging deposit-refund system

Zoltán Pál Lukács Attila Sarkady Anita Boros Zsuzsanna Banász Róbert Kurdi

Publication Name: Sustainability Switzerland

Publication Date: 2021-06-01

Volume: 13

Issue: 11

Page Range: Unknown

Description:

The research subject is the deposit-refund system of beverage packaging (PET, glass and aluminium) in Hungary, which is under development. For the success of the planned system, it is important to consider the population’s opinion. Therefore, data from a primary questionnaire survey were used for the analyses. This questionnaire was conducted in 2020 and resulted in an evaluable sample of 20, 430 people. The study aims to answer the following research questions (Q). Q1. Does the reform of the beverage packaging deposit-refund system in Hungary have a raison d’être? Q2. What are the demographic characteristics (gender, type of residence, qualification) of those who would redeem beverage packaging in their households if the state paid for it? Q3. Do the demographic characteristics and/or the environmental attitudes of individuals significantly influence their perceptions of the planned new system, and how strong is the relationship between them? As for the method for answering the research questions, descriptive statistics and relationship analyses (Cramer’s V and Kendall’s tau) were applied to the closed answers. The results show that the analysis of the primary research provides well-determined directions for legislators and decision makers who develop the detailed operating rules of the new system.

Open Access: Yes

DOI: 10.3390/su13116373

Comprehensive investigation of the corrosion state of the heat exchanger tubes of steam generators

Krisztián Radó Gábor Patek Bernadett Baja N. A. Szabó Varga Kálmán Zoltán Németh Schunk János Z. Homonnay E. Kuzmann

Publication Name: European Corrosion Congress 2009 Eurocorr 2009

Publication Date: 2009-12-01

Volume: 2

Issue: Unknown

Page Range: 1212-1220

Description:

Evaluating the water chemistry in the primary circuit and the effect of chemical decontamination of the heat exchanger tubes performed by the AP-CITROX procedure at Paks NPP (Hungary), a project dealing with the comprehensive investigation of the general corrosion state of the steam generators (SGs) has been initiated. Owing to the fact that there is no investigation method available for the in-situ monitoring of the inner surfaces of heat exchanger tubes, a research program based on sampling as well as on ex-situ electrochemical and surface analytical measurements were developed and elaborated. In the time period of 2000-2008 - within the frame of the above project - 45 stainless steel specimens, cut out from various locations of the steam generators of the Paks NPP were investigated. Besides to the corrosion characteristics (corrosion rate, thickness and chemical composition of the protective oxide-layer) surface properties (morphology, chemical and phase compositions) of the passive layer formed on the inner surface of above heat exchanger tubes were studied, too. The passivity of the inside surface of the stainless steel specimens was measured by voltammetry, the morphology, chemical and phase compositions of the oxide layer formed on the surface were analyzed by SEM-EDX, XRD and CEMS methods. The great number of experimental results allowed us to develop an electronic database which involves the results of the above corrosion experiments, and also some special characteristics of the tubes (e.g. location in the SGs, surface pretreatment by decontamination, if any, etc). Evaluating the main relations among these parameters may contribute to the identification of important processes affecting the corrosion state of steam generators, and highly decisive concerning a life time prolongation project of VVER-type nuclear reactors. In the present work we provide a brief overview on these experiments, some characteristic results, the database developed, as well as some novel findings.

Open Access: Yes

DOI: DOI not available

Machine learning models for the elastic-critical buckling moment of sinusoidal corrugated web beam

Andreas Müller Nurullah Bektaş G. Hajdú

Publication Name: Results in Engineering

Publication Date: 2024-09-01

Volume: 23

Issue: Unknown

Page Range: Unknown

Description:

The torsional stiffness of I-beams with sinusoidal corrugated web is higher than that of flat web beams and the accuracy of the available hand-calculation methods to determine the elastic critical lateral-torsional buckling moment depends on the geometrical parameters of the beam and the web corrugation. This study proposes different machine learning models to determine the elastic lateral-torsional buckling moments of corrugated web beams. Various machine-learning algorithms such as Decision Tree, Random Forests, Gradient Boosting, Support Vector Regression, Catboost, and Deep Neural Network were employed to develop and train for predicting the elastic-critical lateral-torsional buckling moments of I-beams with corrugated web. An extensive dataset with 2250 pieces was constructed using linear buckling analyses on full-shell finite element models to determine the elastic-critical buckling moment of simply supported beams with sinusoidal web corrugation. Based on the statistical parameters of the predicted and test data, the accuracy and safety assessment of the different machine learning models are examined. The accuracy of the available hand-calculation methods is also investigated. The results of the parametric study showed that the overall performance of the different machine learning models is promising, although, not all are directly suited for the described problem.

Open Access: Yes

DOI: 10.1016/j.rineng.2024.102371