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Publications - 6374

Identification of a novel pathogen of the glacial relict Drosera rotundifolia and the impact of the fungus on the conservation of the plant and its habitat

László Palkovics Mátyás Szépligeti János Ágoston A. Tóth L. Szendrei

Publication Name: Fungal Biology

Publication Date: 2025-10-01

Volume: 129

Issue: 6

Page Range: Unknown

Description:

Round-leaved sundew (Drosera rotundifolia L.) is a protected glacial relict plant inhabiting Sphagnum bogs, which are endangered habitats in Hungary. In 2020 and 2021 greyish mycelium growth was observed on the hibernacula of D. rotundifolia in Czech Republic, Germany and Hungary. Samples have been collected in possession of the required permits. The fungus was isolated and identified with classical and molecular methods. Koch's postulates were fulfilled. The novel pathogen was identified as the highly polyphagous Botrytis cinerea in each sample. Simultaneously, field assessments of wild Hungarian populations were carried out. Throughout the survey of three different Hungarian collection sites, altogether 207 hibernacula were carefully examined for gray mold symptoms. Interestingly, only plants grown on milled peat substrate were affected by the pathogen. The antifungal and antimicrobial properties of Sphagnum mosses have been reported by other researchers, which could aid in the protection of D. rotundifolia hibernacula. These results indicate that live Sphagnum moss is a better substrate for this species than milled peat, both for commercial production and for in situ conservation. This information can be vital to the survival and conservation of this species. Sphagnum bogs may protect and allow the expansion and re-establishment of D. rotundifolia.

Open Access: Yes

DOI: 10.1016/j.funbio.2025.101614

Vulnerability assessment of residential buildings in Jeddah: A methodological proposal

O. Kegyes-Brassai Ahmed Al-ghamadi Md Faiz Shah Anas Ahmed Anas Ahmed R. P. Ray

Publication Name: International Journal of Geomate

Publication Date: 2018-01-01

Volume: 14

Issue: 44

Page Range: 134-141

Description:

The City of Jeddah in Saudi Arabia is expanding rapidly, in terms of new buildings and increasing population. The rapid urbanization leads to higher risk from seismic events; even in areas of moderate seismicity such as this city. The present study addresses the rapid evaluation of a large number of buildings in Jeddah involving steps to determine hazard, assessing building stock, and computing vulnerability with a scoring method from FEMA 155. Two districts were selected for investigation based on a cluster analysis applied to population and building data from the local municipality. One selected district was a contemporary developed urbanized area, and the other was a more traditional area. Such selection offered the possibility to compare vulnerability of buildings built according to different seismic codes and to make assumptions about the rest of the city based on typical structures of districts. The basic structural score was determined considering the building structure and moderate seismicity of the region using score modifiers, e.g. vertical irregularity score modifier; soil score modifier assuming sabkahs. The results of the investigation reveal a different level of vulnerability and areas where intervention is needed. The method can be applied for further analysis of the city.

Open Access: Yes

DOI: 10.21660/2018.44.85087

Transformer model identification by artap: A benchmark problem

Miklós Kuczmann Gergely Kovács Attila Szöcs

Publication Name: Periodica Polytechnica Electrical Engineering and Computer Science

Publication Date: 2021-04-27

Volume: 65

Issue: 2

Page Range: 123-130

Description:

The paper presents how Artap can be used for determining the equivalent circuit parameters of a one phase transformer as a benchmark problem. The following unknown parameters of the equivalent circuit are identified: primary resistance and primary leakage reactance, secondary resistance and secondary leakage reactance, finally magnetizing resistance, and magnetizing reactance. The known quantities from measurement are the primary voltage, primary current, power factor, secondary voltage, and the load resistance. Algorithms implemented in Artap are used for determining the transformer parameters and the results are compared with the analytical solution.

Open Access: Yes

DOI: 10.3311/PPee.17606

Maximal entropy and minimal variability OWA operator weights: A short survey of recent developments

Christer Carlsson Robert Fuller

Publication Name: Studies in Fuzziness and Soft Computing

Publication Date: 2018-01-01

Volume: 357

Issue: Unknown

Page Range: 187-199

Description:

The determination of ordered weighted averaging (OWA) operator weights is a very important issue of applying the OWA operator for decision making. One of the first approaches, suggested by O’Hagan, determines a special class of OWA operators having maximal entropy of the OWA weights for a given level of orness; algorithmically it is based on the solution of a constrained optimization problem. In 2001, using the method of Lagrange multipliers, Fullér and Majlender solved this constrained optimization problem analytically and determined the optimal weighting vector. In 2003 Fullér and Majlender computed the exact minimal variability weighting vector for any level of orness using the Karush-Kuhn-Tucker second-order sufficiency conditions for optimality. The problem of maximizing an OWA aggregation of a group of variables that are interrelated and constrained by a collection of linear inequalities was first considered by Yager in 1996, where he showed how this problem can be modeled as a mixed integer linear programming problem. In 2003 Carlsson, Fullér and Majlender derived an algorithm for solving the constrained OWA aggregation problem under a simple linear constraint: the sum of the variables is less than or equal to one. In this paper we give a short survey of numerous later works which extend and develop these models.

Open Access: Yes

DOI: 10.1007/978-3-319-60207-3_12

Parametric Analysis of Metal Matrix Syntactic Foams

Imre Fekete Imre Czinege

Publication Name: Lecture Notes in Mechanical Engineering

Publication Date: 2026-01-01

Volume: Unknown

Issue: Unknown

Page Range: 15-33

Description:

Metal matrix syntactic foams are playing an increasingly important role in different structures. Their application is primarily aimed at weight reduction and energy absorption. The present research uses sensitivity analysis, response surface methodology, and principal component analysis to quantify the effect of matrix yield strength, matrix-to-filler ratio, ceramic sphere wall strength, and wall thickness-to-diameter ratio on the critical compressive strength of metal matrix syntactic foam. It was found that the thickness-to-diameter ratio and strength of the sphere wall are the determining factors in the evolution of the compressive strength, but the matrix strength has less effect on the output.

Open Access: Yes

DOI: 10.1007/978-981-96-6452-8_2

Predictive Repair of Vehicle R1234yf Refrigerant Systems Based on Monitoring of Micro-Leakages

I. Lakatos Jozsef Nagy

Publication Name: Machines

Publication Date: 2026-03-01

Volume: 14

Issue: 3

Page Range: Unknown

Description:

To protect the environment, the R1234yf refrigerant was introduced into the air conditioning systems of modern vehicles. Its price is much higher than that of previous refrigerants, and the gas is slightly flammable, making the prompt detection and repair of even small leaks even more critical. This research aimed to develop a simple, dashboard-based method for serially monitoring and visualizing anomalies in cars after production and before and shortly after delivery. It is possible to infer the presence of minor leaks through online or frequent pressure monitoring after the system has been “resting” (last ignition off for at least 5 h to allow system stabilization: air conditioner vs. outer or engine coolant temperature). Using this method, it can be determined whether the given pressure losses fall within the normal operating range. The essence of the technique is to detect a possible small amount of leakage by monitoring the pressure change (Δp) of the air conditioning system, supported by dashboard(s). The results on the test fleet with 500 cars show that the procedure can be suitable for detecting defects that cause micro-leaks immediately after production. The false-negative detection rate was 0.2, and the false-positive rate was 1.2 at a threshold of ±0.5 bar. Based on a practical example, the method can also be applied to offline cars until the first factory-related claim occurs.

Open Access: Yes

DOI: 10.3390/machines14030268

LPV type model of deformational force in vehicle collisions

Istvan A. Harmati András Rövid Peter Varlaki

Publication Name: Iccc 2009 IEEE 7th International Conference on Computational Cybernetics

Publication Date: 2009-12-01

Volume: Unknown

Issue: Unknown

Page Range: 103-108

Description:

Modeling of the deformational force and absorbed energy plays a very important role in different fields of vehicle engineering. The usually applied FEM based methods give good approximations, but they have extremely large computational complexity. On the other hand there exist simple force models, but they not approximate well in details the real data. The aim of this paper is to introduce a force model for vehicle deformation, which is able to describe the real process and have acceptable complexity. ©2009IEEE.

Open Access: Yes

DOI: 10.1109/ICCCYB.2009.5393952

Systems Engineering Based Sustainability Improvement in Automotive Product Development

Péter Németh Tamás Kolossváry Péter Németh

Publication Name: Journal of Engineering Management and Systems Engineering

Publication Date: 2023-03-01

Volume: 2

Issue: 1

Page Range: 53-60

Description:

Affected by new trends, automobile companies have altered stakeholder requirements on their main product-the automobile. With enactment of new regulations concerning sustainability, new features appeared quickly, such as electrification, sharing services, autonomous mobility and so on. In this study, we present sustainability as a stakeholder and analyze the method of its realization in Systems Engineering (SE) based product development. Formula SAE provides a validated setting to conduct experiments on integrating sustainability into the classical product requirement architectures. By taking into consideration the use of SE or adding other methodological frameworks, findings can establish a new setting in sustainability research. The results of this study may be enlightening for scholars and practitioners and calls for further research on embedding sustainability requirements in automotive product development by using SE.

Open Access: Yes

DOI: 10.56578/jemse020103

On the non hierarchical matrix representation of the negative, non integer order sobolev norms

Béla Kiss

Publication Name: Lecture Notes in Computer Science Including Subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics

Publication Date: 2006-06-29

Volume: 3743 LNCS

Issue: Unknown

Page Range: 663-670

Description:

In this paper a new cyclic matrix representation of the Sobolev norms Ha, a ∈ (-1, 0) are presented. The matrix-vector multiplication by these matrices requires only O(N · log(N)) arithmetic operations, where N is the number of unknowns, The application of the new H-1/2 norm representation as Schur complement preconditioning matrix requires only matrix-vector multiplication. The efficiency of the construction to elliptic problems has been verified by numerical tests. © Springer-Verlag Berlin Heidelberg 2006.

Open Access: Yes

DOI: 10.1007/11666806_76