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Publications - 6383

Reliability based bi-directional evolutionary topology optimization of geometric and material nonlinear analysis with imperfections

Publication Name: Computers and Structures

Publication Date: 2023-10-15

Volume: 287

Issue: Unknown

Page Range: Unknown

Description:

This paper aims to present a novel computational technique for using reliability-based design while taking into account the effect of geometrically and materially nonlinear imperfect analysis. Consequently, a new bi-directional evolutionary structural optimization scheme is developed. A comparison is made between perfect geometrically and materially nonlinear analysis and imperfect geometrically and materially nonlinear analysis topology optimization designs for both deterministic and probabilistic analysis. In the case of probabilistic analysis, relevant parameters such as volume fraction (including manufacturing imprecisions), material properties, and geometrical imperfections (for stability calculations) are assumed to be random variables that follow a normal distribution to represent the uncertainties. The considered numerical examples have successfully illustrated that the proposed method can find the optimal topology for a reliability-based design using perfect geometrically and materially nonlinear analysis and imperfect geometrically and materially nonlinear analysis. Additionally, the results of the topology optimization according to the mean stress and the final optimized shapes have been influenced by introducing a reliability-based design, considering the reliability index as a bound governing the process.

Open Access: Yes

DOI: 10.1016/j.compstruc.2023.107120

Feedback linearization with integrator of DCDC buck converter taking into account parasitic elements

Publication Name: Proceedings 2021 IEEE 19th International Power Electronics and Motion Control Conference Pemc 2021

Publication Date: 2021-04-25

Volume: Unknown

Issue: Unknown

Page Range: 97-101

Description:

This paper presents the feedback linearization based control of DC/DC buck converter, the output voltage controlled. Also, the presence of parasitic elements are not studied in detail in a previous article, therefore the applied state space model are taking into account of those. The high slew rate of the controller cause inrush current during start-up, which have been examined and reduced. The linearized system has been investigated with linear quadratic regulator (LQR) through an example and simulated via Matlab.

Open Access: Yes

DOI: 10.1109/PEMC48073.2021.9432632

Hygrothermal behavior of ultralightweight polystyrene concrete

Publication Name: Pollack Periodica

Publication Date: 2017-08-01

Volume: 12

Issue: 2

Page Range: 53-66

Description:

The aim of the paper is to investigate the hygrothermal properties of a newly developed ultra-lightweight polystyrene concrete, based on laboratory measurements. It describes the measuring process of thermal conductivities, and determines the declared thermal conductivity. The temperature and moisture conversion coefficients are determined, and new approximate functions are introduced. The paper describes the sorption and desorption isotherms, and gives polynomial approximate functions. The paper also investigates the temperature dependency of sorption curves. It determines the water absorption coefficient and the free water saturation. Furthermore, it describes the measuring process of the water vapor permeability. The water vapor resistance factor and water vapor diffusion-equivalent air layer thickness are calculated.

Open Access: Yes

DOI: 10.1556/606.2017.12.2.5

The nexus between environmental diplomacy, policy stringency and renewable energy in advancing sustainability management across G20 countries

Publication Name: Discover Environment

Publication Date: 2026-12-01

Volume: 4

Issue: 1

Page Range: Unknown

Description:

The growing pace of environmental crisis around the world has aggravated the necessity of more vigorous environmental diplomacy and stringency in policy to develop renewable energy and promote sustainable growth in leading economies. This research study examines the relationship between financial globalization (FG), environmental diplomacy (ED), economic growth (GDP), environmental policy stringency (EPS), urbanization (URB), and renewable energy (RE) and ecological sustainability in G20 countries between 1995 and 2023. Based on the CS-ARDL, FMOLS, and DOLS tests, we use the Load Capacity Factor (LCF) as a holistic sustainability measure and analyze the short- as well as longer-term dynamics. Prolonged outcomes reveal that FG, ED, GDP, and URB adversely affect LCF, which suggests an increase in ecological stress. Nonetheless, RE enhances LCF and EPS moderates the negative consequences of globalization. The positive effect of ED is small in the short-run, whereas EPS will have a high contribution to ecological benefits. The ED-GDP relation indicates a long-term worsening of the environment, which underscores the inefficiencies of diplomatic enforcement. These results confirm the modulating effect of stringent environmental policies and the necessity to develop policy frameworks that would harmonize economic integration and sustainability. Urbanization is a threat to the environment unless controlled with sustainable planning, and renewable energy continues to be a major contributor to ecological health in the long run. The study provides practical recommendations to policymakers to incorporate strict regulation, green investment and environmental diplomacy in the strategies of sustainable development.

Open Access: Yes

DOI: 10.1007/s44274-026-00673-9

Biological and therapeutic implications of sex hormone-related gene clustering in testicular cancer

Publication Name: Basic and Clinical Andrology

Publication Date: 2025-12-01

Volume: 35

Issue: 1

Page Range: Unknown

Description:

Background: Gonadotropin dysregulation seems to play a potential role in the carcinogenesis of testicular germ cell tumor (TGCT). The aim of this study was to explore the expression of specific genes related to sex hormone regulation, synthesis, and metabolism in TGCT and to define specific hormonal clusters. Two publicly available databases were used for this analysis (TCGA and GSE99420). By means of hard-threshold regularized KMEANS clustering, we assigned TGCT samples into four clusters defined in respect to different expression of the sex hormone-related genes. We analysed clinical data, protein and gene expression, signaling regarding hormonal clusters. Based on whole-transcriptome gene expression, prediction of anti-cancer drug response was made by RIDGE models. Results: Cluster #1 (12–16%) consisted primarily of non-seminomatous germ cell tumor (NSGCT), characterized by high expression of PRL, GNRH1, HSD17B2 and SRD5A1. Cluster #2 (42–50%) included predominantly seminomas with high expression of SRD5A3, being highly infiltrated by T and B cells. Cluster #3 (8.3–18%) comprised of NSGCT with high expression of CGA, CYP19A1, HSD17B12, HSD17B1, SHBG. Cluster #4 (23–30%), which consisted primarily of NSGCT with a small fraction of seminomas, was outlined by increased expression of STAR, POMC, CYP11A1, CYP17A1, HSD3B2 and HSD17B3. Elevated fibroblast levels and increased extracellular matrix- and growth factor signaling-related gene signature scores were described in cluster #1 and #3. In the combined model of progression-free survival, S2/S3 tumor marker status, hormonal cluster #1 or #3 and teratoma histology, were independently associated with 25–30% increase of progression risk. Based on the increased receptor tyrosine kinase and growth factor signaling, cluster #1, #3 and #4 were predicted to be sensitive to tyrosine kinase inhibitors, FGFR inhibitors or EGFR/ERBB inhibitors. Cluster #2 and #4 were responsive to compounds interfering with DNA synthesis, cytoskeleton, cell cycle and epigenetics. Response to apoptosis modulators was predicted only for cluster #2. Conclusions: Hormonal cluster #1 or #3 is an independent prognostic factor regarding poor progression-free survival. Hormonal cluster assignment also affects the predicted drug response with cluster-dependent susceptibility to specific novel therapeutic compounds.

Open Access: Yes

DOI: 10.1186/s12610-025-00254-5

Unveiling temporal and frequency spillovers: Climate-risk indices and energy futures markets

Publication Name: Journal of Environmental Management

Publication Date: 2025-12-01

Volume: 395

Issue: Unknown

Page Range: Unknown

Description:

This study investigates the time- and frequency-domain spillover dynamics between climate-risk indices, namely the Transition Risk Index (TRI), Physical Risk Index (PRI), Global Climate Policy Uncertainty (GCPU))and major energy futures markets, including ICE Europe Brent crude oil futures (continuation), the global crude benchmark (Brent), ICE Europe Low Sulphur Gasoil futures, a European middle-distillate benchmark (Gasoil), Intercontinental Exchange (ICE) Abu Dhabi Murban crude oil futures (continuation), a Middle Eastern light-sweet benchmark (Murban), Shanghai Crude, New York Harbor Ultra-Low Sulphur Diesel futures (NYMEX) continuation (ULSD), and West Texas Intermediate crude oil futures (NYMEX Light Sweet Crude Oil futures continuation) (WTI). Employing a flexible econometric framework based on TVP-VAR and quantile connectedness, the analysis uncovers non-linear, asymmetric, and time-varying spillovers, with markedly stronger linkages during extreme market conditions and in the short term. Energy commodities, particularly Gasoil and WTI, emerge as significant net transmitters of transition risks, amplifying volatility during periods of stress, while long-term spillovers remain relatively weak, reflecting gradual decarbonization trends. The unique contribution of this paper lies in extending the Arbitrage Pricing Theory (APT) by integrating climate risks as dynamic, state-dependent, and non-diversifiable factors, thereby demonstrating how energy asset sensitivities fluctuate across regimes and quantiles. This approach advances the asset pricing and climate finance literature beyond static models by embedding dynamic connectedness into risk transmission analysis. The findings highlight the systemic nature of climate risks and underscore the importance of adaptive financial regulation, forward-looking climate policy, and flexible risk management practices to mitigate volatility and support the global energy transition. These insights provide actionable guidance for policymakers, regulators, and investors navigating the evolving interplay between climate risks and energy markets.

Open Access: Yes

DOI: 10.1016/j.jenvman.2025.127847

Theoretical Study of the Effect of Weather Conditions on Vehicle Aerodynamic Properties †

Publication Name: Engineering Proceedings

Publication Date: 2024-01-01

Volume: 79

Issue: 1

Page Range: Unknown

Description:

One of the most widely researched fields within the automotive industry is the effect vehicles place on the environment. To achieve a sustainable transport system, reducing the pollution of vehicles is an essential issue. The aim of this paper is to examine how weather conditions influence a vehicle’s operation. The study examines potential methods to evaluate the effect of different weather conditions on the aerodynamic parameters of a vehicle. Aerodynamic properties can be measured with the help of computational fluid dynamics (CFD), a wind tunnel and test-track measurements. On-board diagnostics are also examined to collect data on aerodynamics. These methods can monitor several parameters to measure and visualize the effects of weather conditions. The theoretical background to the related aerodynamic parameters is summarized.

Open Access: Yes

DOI: 10.3390/engproc2024079083

Evaluating the role of blue-green infrastructures in mitigating climate change: a case study of the Hungarian “Green City” program

Publication Name: Clean Technologies and Environmental Policy

Publication Date: 2026-05-01

Volume: 28

Issue: 5

Page Range: Unknown

Description:

Urban environments are increasingly vulnerable to climate change, with extreme weather events expected to become more frequent and severe. This paper addresses sustainable urban development and the importance of stormwater retention, integrating adaptation and mitigation strategies. It evaluates the publicly funded Hungarian “Green City” program’s water management, focusing on blue-green infrastructures. The 198 implemented projects in the program were assessed for green credentials, vegetation concepts, and rainwater retention using public databases of real municipal data and Google Earth spatial analyses rather than hypothetical scenarios. A lifetime climate change impact assessment with sensitivity analysis was conducted using two case studies from the “Green City” program, highlighting the benefits of prioritizing rainwater over tap water for irrigation. The study proposes a three-pillar—environmental as operational carbon footprint, economic as extended net present value (NPV), and social as accessibility and recreational benefit—evaluation method for urban blue-green developments. It found that many projects rely on tap water irrigation, thus resulting in higher lifetime carbon emissions. The financial assessment of carbon footprint within the extended NPV method emphasizes the need for improved green area irrigation strategies. By modernizing irrigation practices and implementing effective rainwater retention measures, blue-green infrastructures can significantly reduce carbon dioxide emissions while improving long-term economic performance and social benefits through improved usability. The research offers valuable insights into the role of blue-green infrastructures in urban development to combat climate change. The combined three-pillar framework integrating LCA to assess green projects is a transferable decision-support tool that can be adapted to locally available data, advocating the use of rainwater over tap water to achieve environmental, social, and economic benefits. Unlike earlier studies that used hypothetical scenarios, this research relies on the implemented projects of the “Green City” development program with their observed designs and available real data, thus providing a framework for urban blue-green implementations to integrate sustainable practices and effectively address the challenges posed by climate change.

Open Access: Yes

DOI: 10.1007/s10098-026-03501-z

Evaluation Of hardening performance of cooling media by using inverse heat conduction methods and property prediction

Publication Name: Strojniski Vestnik Journal of Mechanical Engineering

Publication Date: 2010-04-28

Volume: 56

Issue: 2

Page Range: 77-83

Description:

A sequential numerical method for characterization of hardening performance of quenchants applied for steel quenching is outlined here. This novel method is based on the specific processing of measured time-temperature samples performed as a result of cooling curve tests. As a function of surface temperature the heat transfer coefficient, characterises the heat transfer during cooling and is calculated using an iterative inverse algorithm. The heat transfer coefficient is used for the calculation of the microstructural constituents and the hardness profile of cylindrical samples of arbitrary diameters. The hardening performance of the media is evaluated by the estimated hardness of the specimen obtained by heat treatment. © 2010 Journal of Mechanical Engineering. All rights reserved.

Open Access: Yes

DOI: DOI not available