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Publications - 6342

A coupled impact of different management and soil moisture on yield of winter wheat (Triticum aestivum L.) in dry conditions at locality Mezoföld, Hungary

G. Milics

Publication Name: Journal of Hydrology and Hydromechanics

Publication Date: 2021-03-01

Volume: 69

Issue: 1

Page Range: 76-86

Description:

Variable rate technology (VRT) in nutrient management has been developed in order to apply crop inputs according to the required amount of fertilizers. Meteorological conditions rarely differ within one field; however, differences in soil conditions responding to precipitation or evaporation results within field variations. These variations in soil properties such as moisture content, evapotranspiration ability, etc. requires site-specific treatments for the produced crops. There is an ongoing debate among experts on how to define management zones as well as how to define the required amount of fertilizers for phosphorus and nitrogen replenishment for winter wheat (Triticum aestivum L.) production. For management zone delineation, vegetation based or soil based data collection is applied, where various sensor technology or remote sensing is in help for the farmers. The objective of the study reported in this paper was to investigate the effect of soil moisture data derived from Sentinel-2 satellite images moisture index and variable rate phosphorus and nitrogen fertilizer by means of variable rate application (VRA) in winter wheat in Mezoföld, Hungary. Satellite based moisture index variance at the time of sowing has been derived, calculated and later used for data comparison. Data for selected points showed strong correlation (R2 = 0.8056; n = 6) between moisture index and yield, however generally for the whole field correlation does not appear. Vegetation monitoring has been carried out by means of NDVI data calculation. On the field level, as indicated earlier neither moisture index values at sowing nor vegetation index data was sufficient to determine yield. Winter wheat production based on VRA treatment resulted significant increase in harvested crop: 5.07 t/h in 2013 compared to 8.9 t/ha in 2018. Uniformly managed (control) areas provided similar yield as VRA treated areas (8.82 and 8.9 t/ha, respectively); however, the input fertilizer was reduced by 108 kg/ha N and increased by 37 kg/ha P.

Open Access: Yes

DOI: 10.2478/johh-2020-0039

Fast and direct screening of copper in micro-volumes of distilled alcoholic beverages by high-resolution continuum source graphite furnace atomic absorption spectrometry

Gabriella Dravecz Nikoletta Laczai Áron Marosi Bence Marlok Norbert Szoboszlai Zsolt Ajtony László Bencs Christina Streli

Publication Name: Food Chemistry

Publication Date: 2016-12-15

Volume: 213

Issue: Unknown

Page Range: 799-805

Description:

HR-CS-GFAAS methods were developed for the fast determination of Cu in domestic and commercially available Hungarian distilled alcoholic beverages (called pálinka), in order to decide if their Cu content exceeds the permissible limit, as legislated by the WHO. Some microliters of samples were directly dispensed into the atomizer. Graphite furnace heating programs, effects/amounts of the Pd modifier, alternative wavelengths (e.g., Cu I 249.2146 nm), external calibration and internal standardization methods were studied. Applying a fast graphite furnace heating program without any chemical modifier, the Cu content of a sample could be quantitated within 1.5 min. The detection limit of the method is 0.03 mg/L. Calibration curves are linear up to 10–15 mg/L Cu. Spike-recoveries ranged from 89% to 119% with an average of 100.9 ± 8.5%. Internal calibration could be applied with the assistance of Cr, Fe, and/or Rh standards. The accuracy of the GFAAS results was verified by TXRF analyses.

Open Access: Yes

DOI: 10.1016/j.foodchem.2016.06.090

Soluble factors from Aspergillus fumigatus promote NF-κB/AKT/ERK activation and pro-tumor phenotypes in lung cancer cells in vitro

D. U. Ozsahin U. Saeed Z. Z. Piracha Zengxia Ma Dilber Uzun Ozsahin Di Xu Yang Shen Xia Bian

Publication Name: Archives of Microbiology

Publication Date: 2026-06-01

Volume: 208

Issue: 6

Page Range: Unknown

Description:

Role of environmental fungi and Aspergillus fumigatus in respiratory diseases remains evident; however, its contribution to directly influencing lung cancer progression remains obscure. In this study, we investigated the effect of Aspergillus fumigatus extract (AFE) on the development of tumor-promoting characteristics in human lung cancer cell lines. The organism was distinguished based on Lactophenol Cotton Blue staining and further distinguished with protein expression patterns via SDS-PAGE and BCA analysis. A549 and H1299 lung adenocarcinoma human cell lines were challenged with AFE, and various cellular responses were monitored simultaneously for cell viability, proliferative activity, inflammatory gene expression, DNA damage expression, and migratory responses. AFE caused increased cell viability and exhibited cellular characteristics of highly proliferating cells with significant expression of Cyclin D1 and c-MYC. Highly inflammatory gene expression responses and protein expressions of AKT, ERK1/2, and NF-κB signaling pathways were noticed at both the gene and protein expression levels with NF-κB nuclear translocation verified with confocal microscopy studies. DNA damage expression markers like γ-H2AX, p-ATM, and p53 significantly contributed with observable genomic DNA cleavage. Additionally, AFE-exposed cells exhibited faster wound closure and expression of Epithelial-mesenchymal transition-associated factors contributing to cell migration and therapeutic efficacy of this combined approach needs further investigation and development into a targeting therapeutic agent against lung cancer.

Open Access: Yes

DOI: 10.1007/s00203-026-04849-y

Novel Technique for Reducing Geometrical Inaccuracies of Clamped Workpiece During Machining: A Hybrid Method

Dániel Ledenyák Tamás Rosta Hajnalka Hargitai

Publication Name: Advances in Transdisciplinary Engineering

Publication Date: 2024-01-01

Volume: 59

Issue: Unknown

Page Range: 269-276

Description:

The aim of this paper is to provide a novel technique in production technology, which ensures the adequate tightening torque of workpiece by a vise connector to minimize the effect of elastic deformation, therefore geometrical inaccuracies roughness, during machining process. This effect emerges if the clamping force is excessively high, resulting in a deformed workpiece with a slightly convex surface. Once this surface is machined and the clamping force is released, the material returns to its initial shape and the newly machined flat surface will be concaved, resulting geometrical inaccuracy. The method is based on a simple workpiece, where the elastic deformation is numerically modelled and experimentally measured as a function of different clamping heights and tightening forces. During the experiments, the workpiece is tightened by bolts, step by step, and in each step, the deformation of the surface is measured with a coordinate measuring machine equipped with a Touch Probe Measurement system. This measurement process is followed by finite element modelling, where the same system, with identical boundary conditions (load, constraints, material properties), are computationally created to compare the numerically and experimentally obtained results. As a result of evaluating various cases, a user-friendly database was established that provides recommendations for specific geometry, position, and capture height. Our model can also propose a minimum clamping height if geometry, position, and maximum force(s) are specified during machining.

Open Access: Yes

DOI: 10.3233/ATDE240555

Simulation of an active cooling system for photovoltaic modules

Lotfi Abdelhakim

Publication Name: Aip Conference Proceedings

Publication Date: 2016-06-08

Volume: 1738

Issue: Unknown

Page Range: Unknown

Description:

Photovoltaic cells are devices that convert solar radiation directly into electricity. However, solar radiation increases the photovoltaic cells temperature [1] [2]. The temperature has an influence on the degradation of the cell efficiency and the lifetime of a PV cell. This work reports on a water cooling technique for photovoltaic panel, whereby the cooling system was placed at the front surface of the cells to dissipate excess heat away and to block unwanted radiation. By using water as a cooling medium for the photovoltaic solar cells, the overheating of closed panel is greatly reduced without prejudicing luminosity. The water also acts as a filter to remove a portion of solar spectrum in the infrared band but allows transmission of the visible spectrum most useful for the PV operation. To improve the cooling system efficiency and electrical efficiency, uniform flow rate among the cooling system is required to ensure uniform distribution of the operating temperature of the PV cells. The aims of this study are to develop a 3D thermal model to simulate the cooling and heat transfer in Photovoltaic panel and to recommend a cooling technique for the PV panel. The velocity, pressure and temperature distribution of the three-dimensional flow across the cooling block were determined using the commercial package, Fluent. The second objective of this work is to study the influence of the geometrical dimensions of the panel, water mass flow rate and water inlet temperature on the flow distribution and the solar panel temperature. The results obtained by the model are compared with experimental results from testing the prototype of the cooling device.

Open Access: Yes

DOI: 10.1063/1.4952279

Biomedical Engineering Education and Related Research Activity in Hungary

B. Benyo Péter Somogyi Levente Kovács L. Szilágyi Z. Benyó Péter Várady

Publication Name: Annual International Conference of the IEEE Engineering in Medicine and Biology Proceedings

Publication Date: 2003-12-01

Volume: 4

Issue: Unknown

Page Range: 3533-3535

Description:

Biomedical Engineering is a relatively new interdisciplinary science. This paper presents the biomedical engineering activity, which is carried out at Budapest University of Technology and Economics and its partner institutes. In the first part the main goals and the curriculum of the Biomedical Engineering ducation Program (BMEEP) is presented. The second part of the paper summarizes the most important biomedical engineering researches carried out mostly in the Biomedical Engineering Laboratory of our university.

Open Access: Yes

DOI: DOI not available

Numerical simulation of boundary value radiative tri-hybrid nanofluid flow subject to exponential heat source/sink past a porous stretching surface

Muhammad Bilal Hijaz Ahmad Munawar Alam Naveed Khan Gulzar Ali Khan

Publication Name: Results in Engineering

Publication Date: 2026-06-01

Volume: 30

Issue: Unknown

Page Range: Unknown

Description:

The energy and mass transference through ternary nanofluid (TNF) over a stretching spinning sheet is estimated in the present study. The TNF has been prepared by the distribution of magnesium oxide (MgO), titanium dioxide (TiO2), and cobalt ferrite (CoFe2O4) nanoparticles (NPs) in water. The study of the TNF over a rotating stretching sheet can be directly used in optimizing the performance of solar thermal collector, high-power electronics cooling, and aerospace heat shields. Such flow has a vital role in the optimization of lubrication processes and nuclear reactor cooling in which high thermal conductivity and centrifugal flow manipulation is needed. The TNF flow has been calculated under the consequence of mixed convection, thermal radiation, constant and exponential heat source/sink, magnetic field, and porous medium. The flow scenario is mathematically stated in the form of a nonlinear system of PDEs (partial differential equations). The set of PDEs is transfigured into the non-dimensional system of ODEs (ordinary differential equations), by means of the similarity variables. The results are obtained through the bvp4c code (Matlab built-in package). The percent error between present and published study at Pr =5.0 is 0.0034541%, which ensure the accuracy of the proposed model and applied methodology. The energy transfer rate drops by up to 20.4049%, 25.5465% and 32.4766% by varying the exponential heat source/sink factor from -1.0 t0 1.0 in case of nano, hybrid and ternary nanofluid respectively. The transfer rate enhances up to 52.7911% and 51.2236% by varying heat radiation and Dufour number from 1.0 to 3.0 and 1.5 to 3.5 in case of THNF, respectively.

Open Access: Yes

DOI: 10.1016/j.rineng.2026.110591

Testing the speed-up of parallel discrete event simulation in heterogeneous execution environments

István Derka Gábor Lencse

Publication Name: 11th International Industrial Simulation Conference 2013 Isc 2013

Publication Date: 2013-01-01

Volume: Unknown

Issue: Unknown

Page Range: 101-107

Description:

This paper deals with the experimental testing and verification of the earlier proposed load balancing and coupling factor criteria for the conservative parallel discrete event simulation in heterogeneous execution environments whether they can ensure a good speed-up. The definition of the relative speed-up is extended to the heterogeneous systems in a natural way. This definition is used to measure the efficiency of the parallel simulation executed by heterogeneous systems. A closed queueing network is used as the simulation model, and it is executed on different heterogeneous test systems. Among several scenarios, it is demonstrated on the example of a heterogeneous system containing 87 CPU cores of 5 different types that a good speed-up can be achieved using the load balancing and coupling factor criteria. It is shown that the extension of the definition of the relative speed-up to the heterogeneous systems made it easy to judge the speed-up of parallel discrete event simulation in heterogeneous execution environments.

Open Access: Yes

DOI: DOI not available

The impact of the hotel industry on the competitiveness of tourism destinations in Hungary

Albert Tóth Attila

Publication Name: Journal of Competitiveness

Publication Date: 2016-12-01

Volume: 8

Issue: 4

Page Range: 85-104

Description:

This paper focuses on a complex question from the perspective of the hotel industry. It tries to draw attention to the importance of hotels, enhancing it on the basis of the tourism destination competitiveness models and introducing the role and place of the hotel industry in the most important models. The hotel industry research evaluates the most important tourism destinations of Hungary on the micro-regional level that justifies the importance and contribution of the hotels and accommodations to competitiveness and success of tourism destinations with exact results. As a result of the research, the micro-regional destinations can be ranged within three groups in Hungary. In the first group of the most developed and most competitive tourism destinations, the hotel industry plays a very important role. In these regions, the hotel industry has a significant effect not only on competitiveness of tourism but also on general development of the regions. In the second group, which can be still called tourism destination, tourism and the hotel industry both play a significant role, but only the competitiveness of tourism can be considered good, the effects of the tourism on general development of the region can be proved only to a lesser extent. In the third group, the effects of tourism and the hotel industry can only be experienced to a lesser extent. The majority of these regions are not considered to be attractive tourism destinations for tourists any more.

Open Access: Yes

DOI: 10.7441/joc.2016.04.06