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Analysis of the Heating of Steel Structures During Fire Load

Dániel Balázs Merczel Éva Lublóy Zoltán Major János Szép László Bodnár

Publication Name: Emerging Science Journal

Publication Date: 2024-02-01

Volume: 8

Issue: 1

Page Range: 1-16

Description:

During the preparation of our article, we present in detail the changes in the thermotechnical parameters of carbon steel and corrosion resistance during fire. After that, we present in detail the calculation of the heating of steel structures without fire protection. We feel this is important because it is not possible to provide stainless steel with fire protection for aesthetic reasons, and it is also not typical for thin-walled galvanized structures. We also present the calculation of structures with fire protection in detail and present the background for editing commonly used nomograms. Such a nomogram is also available in the literature, but it can be considered true with significant simplifications. During the practical planning, the applied fire protection regulations were highly standardized. Realizing that there is no design nomogram for these types of solutions, we created and published them in our article. The advantage of these is that the applicable design can also be found as the optimum of the designs considered to be potentially good. With this solution, we can save time during planning, and we can also get a more cost-effective solution for the fire protection cover. The advantage of the presented method is that, if required, the editing of the nomograms can be extended to other designs by knowing the material characteristics and the layer thickness. Another option of the presented method is that the solution can also be applied to special fire loads, and nomograms can be produced for them as well (e.g., hydrocarbon fires).

Open Access: Yes

DOI: 10.28991/ESJ-2024-08-01-01

Innovation-Driven E-Commerce Growth in the EU: An Empirical Study of the Propensity for Online Purchases and Sustainable Consumption

Gagan Deep Sharma Maria M. Grzelak Elżbieta Roszko-Wójtowicz Barbara Dańska-Borsiak

Publication Name: Sustainability Switzerland

Publication Date: 2024-02-01

Volume: 16

Issue: 4

Page Range: Unknown

Description:

The e-commerce sector has experienced significant growth in the past two decades, outpacing other economic sectors and contributing to sustainable consumption, increased labour productivity, competitiveness, consumer incomes, and GDP growth. This trend is expected to continue, making e-commerce a key driver of sustainable economic growth in Europe. This study aims to explore the relationship between a nation’s innovation level and its population’s inclination towards online shopping in various EU member states. It hypothesizes that higher innovation levels within a country lead to a greater tendency for online purchases. This study conducts a thorough analysis of the interplay between European economies’ innovation levels and the e-commerce market’s evolution. A composite innovation index was created using the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) methodology, and panel data models were utilized to examine the dependencies, with data from Eurostat and the Global Innovation Index. The focus is on the period from 2019 to 2021, which was marked by unique market dynamics and the impact of the COVID-19 pandemic. The findings confirm the significant role of innovation in driving e-commerce expansion within the context of sustainable consumption, supporting the main hypothesis. This research also highlights the pandemic’s positive effect on the e-commerce sector. The pandemic-induced changes in consumer behaviour, particularly due to social isolation and crises in certain economic sectors, have emphasized the importance of online shopping. Notably, the most active online shoppers are identified in the 25 to 54 age group, revealing a key demographic trend.

Open Access: Yes

DOI: 10.3390/su16041563

First Report of Saffron Latent Virus in Crocus sativus from Hungary

László Palkovics Réka Sáray János Ágoston Dóra Pinczés Asztéria Almási Katalin Salánki

Publication Name: Plant Disease

Publication Date: 2024-02-01

Volume: 108

Issue: 2

Page Range: 540

Description:

No description provided

Open Access: Yes

DOI: 10.1094/PDIS-09-23-1765-PDN

Hydrodynamic Modeling and Comprehensive Assessment of Pier Scour Depth and Rate Induced by Wood Debris Accumulation

Muhanad Al-Jubouri Richard P. Ray

Publication Name: Hydrology

Publication Date: 2024-04-01

Volume: 11

Issue: 4

Page Range: Unknown

Description:

This study mainly investigates the impact of debris accumulation on scour depth and scour hole characteristics around bridge piers. Through controlled experiments with uniform sand bed material, the influence of various debris shapes (high wedge, low wedge, triangle yield, rectangular, triangle bow, and half-cylinder), upstream debris length, downstream debris extension, and debris thickness on scour depth and scour hole area and volume around the cylindrical pier were analyzed. The findings revealed that the shape and location of debris in the water column upstream of piers are key factors that determine the depth of scour, with high wedge shapes inducing the deepest scour and potentially the largest scour hole, particularly when positioned close to the pier and fully submerged. Scenarios in which triangle bow debris was submerged at full depth upstream of the pier closely resembled situations devoid of debris. Conversely, debris extension downstream of the pier was found to reduce local scour depth while concurrently enlarging the dimensions of the scour hole. The existing scour prediction equations tend to overestimate scour depth in scenarios involving debris, particularly when applying effective and equivalent pier width. This discrepancy arises because these equations were originally developed to predict scour depth around piers in the absence of debris. In response, a refined model for predicting scour induced by debris was proposed, integrating factors such as upstream debris length, downstream extension, obstruction percentage, and debris shape factor. This model demonstrated strong agreement with experimental data within the scope of this study and underwent further validation using additional experimental datasets from other research endeavors. In conclusion, this experimental study advances the comprehension of scour processes around cylindrical bridge piers, providing valuable insights into the role of debris characteristics and positioning.

Open Access: Yes

DOI: 10.3390/hydrology11040052

Advanced elasto-plastic topology optimization of steel beams under elevated temperatures

Marco Domaneschi Majid Movahedi Rad Raffaele Cucuzza Muayad Habashneh

Publication Name: Advances in Engineering Software

Publication Date: 2024-04-01

Volume: 190

Issue: Unknown

Page Range: Unknown

Description:

A topology optimization algorithm of steel beams under the influence of elevated temperature, considering the geometrically nonlinear analysis of imperfect structures, is proposed in this work. The proposed methodology is developed for addressing topology optimization problems in the presence of initial geometric imperfections and thermoelastic-plastic analysis by developing the bi-directional evolutionary structural optimization (BESO) method. Two comprehensive examples of lipped channel beams and steel I-section beams are provided to demonstrate the effectiveness of the proposed approach. The considered examples explore the impact of elevated temperature on the topology optimization of imperfect steel beams, considering the interplay between thermal effects, structural imperfections, and nonlinear behavior. The results highlight the significance of integrating temperature effects in achieving optimal and robust steel beam designs. Furthermore, the openings generated by the proposed algorithm can efficiently disrupt the continuous heat flow within the material, leading to regions with reduced thermal conductivity compared to solid regions.

Open Access: Yes

DOI: 10.1016/j.advengsoft.2024.103596

Optimising Portfolio Risk by Involving Crypto Assets in a Volatile Macroeconomic Environment

Gergő Thalmeiner László Pataki Attila Bányai Tatay Tibor

Publication Name: Risks

Publication Date: 2024-04-01

Volume: 12

Issue: 4

Page Range: Unknown

Description:

Portfolio diversification is an accepted principle of risk management. When constructing an efficient portfolio, there are a number of asset classes to choose from. Financial innovation is expanding the range of instruments. In addition to traditional commodities and securities, other instruments have been added. These include cryptocurrencies. In our study, we seek to answer the question of what proportion of cryptocurrencies should be included alongside traditional instruments to optimise portfolio risk. We use VaR risk measures to optimise the process. Diversification opportunities are evaluated under normal return distributions, thick-tailed distributions, and asymmetric distributions. To answer our research questions, we have created a quantitative model in which we analysed the VaR of different portfolios, including crypto-diversified assets, using Monte Carlo simulations. The study database includes exchange rate data for two consecutive years. When selecting the periods under examination, it was important to compare favourable and less favourable periods from a macroeconomic point of view so that the study results can be interpreted as a stress test in addition to observing the diversification effect. The first period under examination is from 1 September 2020 to 31 August 2021, and the second from 1 September 2021 to 31 August 2022. Our research results ultimately confirm that including cryptoassets can reduce the risk of an investment portfolio. The two time periods examined in the simulation produced very different results. An analysis of the second period suggests that Bitcoin’s diversification ability has become significant in the unfolding market situation due to the Russian-Ukrainian war.

Open Access: Yes

DOI: 10.3390/risks12040068

Impact of Projects with Future Potential on the Global Competitiveness Index of Countries

Laszlo Vasa Jeffrey Yi Lin Forrest Satyanand Singh Akbota Akzambekkyzy Shynara Sarkambayeva

Publication Name: Emerging Science Journal

Publication Date: 2024-04-01

Volume: 8

Issue: 2

Page Range: 557-573

Description:

The concept of project success has evolved from the perspective of conforming to the project triangle to that of benefiting the environment, and then from the perspective of the following generation. Scientists increasingly assert that successful projects require a set of criteria that include such item(s) as future potential. The meaning of project success varies depending on where it is executed. The purpose of this study is to identify whether projects with future potential have a certain effect on indicators of the Global Competitiveness Index (GCI) of the Republic of Kazakhstan (RK) and what other success criteria are inherent in such projects. By using the method of descriptive analysis of data collected from 107 experts and analyzing 19 influential projects, the study revealed that projects oriented towards the future have a significant impact on the indicators of the GCI in the RK. This finding confirms the necessity of considering the long-term sustainability and social significance of projects when assessing their successes. Additionally, a specific combination of success criteria that contributes most to this impact was identified. This research provides a brand-new understanding of project success criteria in the context of their impact on the GCI and emphasizes the importance of considering future potential in project planning and evaluation.

Open Access: Yes

DOI: 10.28991/ESJ-2024-08-02-012

Effects of Local Soil Profiles on Seismic Site Response Analysis

Ayele Chala Richard P. Ray

Publication Name: Periodica Polytechnica Civil Engineering

Publication Date: 2024-03-18

Volume: 68

Issue: 2

Page Range: 403-410

Description:

Local soil conditions play a significant role in the intensity variations of seismic waves during earthquakes. These variations can be either amplified or de-amplified depending on the specific soil conditions. This study aimed to assess the impact of different soil profiles on seismic site responses. The study considered four types of site profiles: sand (Sa), clay (Cl), sand overlying clay (SaCl), and clay overlying sand (ClSa) profiles. To simulate the ground motion, we selected seven sets of strong earthquake records from the European Strong-Motion Database. These records were selected according to Eurocode-8 with a peak ground acceleration (PGA) of 0.24 g, site class A using REXEL computer program. The records were then applied to the bedrock at a depth of 30 meters. Subsequently, a series of 1-D equivalent linear (EQL) response analyses were performed using the STRATA. Amplification factors (AFs) and surface acceleration time histories provided quantitative evaluations for our analysis results. The results demonstrated that site profiles with clay overlying bedrock (SaCl and Cl profiles) exhibited higher seismic amplification and peak ground acceleration in comparison to site profiles with sand overlying bedrock (Sa and ClSa profiles). The maximum median AF is calculated from the SaCl site profile, while the minimum median AF was calculated from the ClSa profile. The relative difference between the maximum and the minimum median AFs was about 33.7%. Based on these results, we can conclude that soft local soils have a pronounced effect on the amplification of seismic waves compared to stiff local soils.

Open Access: Yes

DOI: 10.3311/PPci.22148

Application Analysis of a Novel Reduction Method for Spurious Oscillations in 2D Impact Problems

Balázs Pere Daniel Serfozo

Publication Name: Advances in Transdisciplinary Engineering

Publication Date: 2024-01-01

Volume: 59

Issue: Unknown

Page Range: 231-239

Description:

The numerical solution of impact problems are oftentimes problematic due to the presence of spurious oscillations in the resulting functions. Eliminating these oscillations is complicated and requires a damping effect to be exerted in the solution. In the proposed method, viscous damping has been applied with a special damping character. Using this scheme, the numerical solution of 2D impact problems contains significantly less oscillations compared to other widely applied methods. In quantitative terms, an improvement of 2.42% and 9.29% or more can be achieved in the time evolution of the velocity and the pressure, respectively.

Open Access: Yes

DOI: 10.3233/ATDE240550