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Synergistic dynamics unveiled: Interplay between rare earth prices, clean energy innovations, and tech companies' market resilience amidst the Covid-19 pandemic and Russia-Ukraine conflict

Laszlo Vasa Grzegorz Mentel Xiaoming Yang Ashfaq Ahmad Md Monirul Islam

Publication Name: Resources Policy

Publication Date: 2024-02-01

Volume: 89

Issue: Unknown

Page Range: Unknown

Description:

Rare earth elements play a crucial role in supporting low-carbon energy generation technologies, such as electric motors in electric vehicles and the production of wind turbines. Additionally, these elements are utilized in a wide range of products manufactured by tech companies, including smartphones, aerospace components, and microelectronics. This paper aims to investigate the interplay between rare earth element prices (REMX), clean energy innovations (NEX), and the market of tech companies (PSE) from February 2018 to February 2023. To analyze the interdependencies between these markets, the study employs the cross-quantilogram (CQ) and wavelet local multiple correlation (WLMC) techniques. The findings of the investigation reveal a positive correlation between rare earth elements and the clean energy market, but only when both markets are in their respective extreme quantiles (10th and 90th). However, when the clean energy market is in a lower quantile and REMX is in a higher one for an extended period, there is either no significant interdependence or a negative relationship. Furthermore, the study identifies a positive co-movement between PSE and REMX in the short, intermediate, and extremely long-term. However, this relationship turns negative in the long run. The values of the coefficients fluctuate over time, particularly at larger scale periods of 8–16 when using the WLMC procedure. These findings have notable implications for stakeholders, including investors, managers, and policymakers, who are linked to the field of mineral resources and industries reliant on rare earth element-based technologies.

Open Access: Yes

DOI: 10.1016/j.resourpol.2023.104615

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

Remanufacturing a Synchronous Reluctance Machine with Aluminum Winding: An Open Benchmark Problem for FEM Analysis

Miklós Kuczmann Mihaly Katona Tamas Orosz Zoltan Nemeth Dávid Gábor Bányai

Publication Name: Electronics Switzerland

Publication Date: 2024-02-01

Volume: 13

Issue: 4

Page Range: Unknown

Description:

The European Union’s increasing focus on sustainable and eco-friendly product design has resulted in significant pressure on original equipment manufacturers to adopt more environmentally conscious practices. As a result, the remanufacturing of end-of-life electric machines is expected to become a promising industrial segment. Identifying the missing parameters of these types of machines will play an essential role in creating feasible and reliable redesigns and remanufacturing processes. A few case studies related to this problem have been published in the literature; however, some novel, openly accessible benchmark problems can facilitate the research and function as a basis for comparing and validating novel numerical methods. This paper presents the identification process of an experimental synchronous machine. It outlines methodologies for identifying material properties, winding schemes, and other critical parameters for the finite element analysis and modelling of electric machines with incomplete information. The machine in question is intended for remanufacturing, with the plan to replace its faulty winding with an aluminium-based alternative. It also serves as an open benchmark problem for researchers, designers, and practitioners.

Open Access: Yes

DOI: 10.3390/electronics13040727

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

A Novel Approach to Swell Mitigation: Machine-Learning-Powered Optimal Unit Weight and Stress Prediction in Expansive Soils

Ammar N. Alnmr Mounzer Omran Alzawi R. P. Ray

Publication Name: Applied Sciences Switzerland

Publication Date: 2024-02-01

Volume: 14

Issue: 4

Page Range: Unknown

Description:

Expansive soils pose significant challenges to structural integrity, primarily due to volumetric changes that can lead to detrimental consequences and substantial economic losses. This study delves into the intricate dynamics of expansive soils through loaded swelling pressure experiments conducted under diverse conditions, encompassing variations in the sand content, initial dry unit weight, and initial degree of saturation. The findings underscore the pronounced influence of these factors on soil swelling. To address these challenges, a novel method leveraging machine learning prediction models is introduced, offering an efficient and cost-effective framework to mitigate potential hazards associated with expansive soils. Employing advanced algorithms such as decision tree regression (DTR), random forest regression (RFR), gradient boosting regression (GBR), extreme gradient boosting (XGBoost), support vector regression (SVR), and artificial neural networks (ANN) in the Python software 3.11 environment, this study aims to predict the optimal applied stress and dry unit weight required for soil swelling mitigation. Results reveal that XGBoost and ANN stand out for their precision and superior metrics. While both performed well, ANN demonstrated exceptional consistency across training and testing phases, making it the preferred choice. In the tested dataset, ANN achieved the highest R-squared values (0.9917 and 0.9954), lowest RMSE (7.92 and 0.086), and lowest MAE (5.872 and 0.0488) for predicting optimal applied stress and dry unit weight, respectively.

Open Access: Yes

DOI: 10.3390/app14041411

Optimizing structural topology design through consideration of fatigue crack propagation

Majid Movahedi Rad Muayad Habashneh

Publication Name: Computer Methods in Applied Mechanics and Engineering

Publication Date: 2024-02-01

Volume: 419

Issue: Unknown

Page Range: Unknown

Description:

This paper presents an advanced approach for structural topology optimization by incorporating fatigue crack propagation analysis. The extended finite element method (X-FEM) is employed to model initial crack propagation, while the Paris model serves as the basis for simulating fatigue crack growth. The proposed methodology aims to optimize the structural design by minimizing compliance while considering volume and fatigue constraints. The proposed method employs the developed bi-directional evolutionary structural optimization (BESO) algorithm. The accuracy of the proposed technique is validated through the solution of benchmark problem and is further demonstrated in its effectiveness and robustness by examining several numerical examples. The optimization process considers various crack conditions, including the absence of cracks, horizontal and vertical cracks of different lengths. The optimized topologies obtained through the proposed algorithm clearly demonstrate the impact of crack presence, crack direction, and crack length on the material distribution. Furthermore, the convergence histories of the objective function, represented by mean compliance, highlight the influence of crack length on the stiffness and converged compliance of the structure. The results demonstrate its ability to adapt the material distribution based on fatigue cracks propagation conditions and achieve optimal topologies that balance structural integrity and performance.

Open Access: Yes

DOI: 10.1016/j.cma.2023.116629

The Role of BIM in Managing Risks in Sustainability of Bridge Projects: A Systematic Review with Meta-Analysis

Zsolt Bencze Rana Ahmad Maya Dema Munef Ahmad László Gáspár

Publication Name: Sustainability Switzerland

Publication Date: 2024-02-01

Volume: 16

Issue: 3

Page Range: Unknown

Description:

With the significant and rapid growth observed in bridge projects worldwide, the associated environmental, economic, and social concerns are on the rise. A systematic review of bridge sustainability with meta-analysis according to the PRISMA guidelines was performed, aiming to improve understanding of the importance of using building information modeling (BIM) in bridge projects by investigating the role of proper implementation of this technology to avoid and mitigate risks and improve sustainability. The relevant international literature was collected and scrutinized. The findings demonstrated that the accurate implementation of BIM significantly enhances the efficient management of risks in bridge projects. Consequently, this has a positive effect on improving the three essential (environmental, economic, and social) aspects of sustainability. The impact mentioned is especially apparent in enhancing the management of information throughout the entire lifespan of a bridge. This, in turn, facilitates precise decision-making during the design phase, aligns with assessments of environmental impact, enables real-time monitoring during execution, effectively manages the maintenance of the structure, facilitates efficient allocation and utilization of resources, and improves design practices by providing designers with accurate information. Delving into the nuances of this review has shed light on the transformative potential of BIM in shaping sustainable bridge projects, laying the groundwork for future advancements in this critical field.

Open Access: Yes

DOI: 10.3390/su16031242

Particle Number Concentration and SEM-EDX Analyses of an Auxiliary Heating Device in Operation with Different Fossil and Renewable Fuel

Ibolya Zsoldos György Szabados Péter Nagy I. Szabó

Publication Name: Inventions

Publication Date: 2024-02-01

Volume: 9

Issue: 1

Page Range: Unknown

Description:

Pollution from road vehicles enters the air environment from many sources. One such source could be if the vehicle is equipped with an auxiliary heater. They can be classified according to whether they work with diesel or gasoline and whether they heat water or air. The subject of our research series is an additional heating system that heats the air, the original fuel is gasoline. This device has been built up in a modern engine test bench, where the environmental parameters can be controlled. The length of the test cycle was chosen to be 30 min. The tested fuels were E10, E30, E100 and B7. A 30-min operating period has been chosen in the NORMAL operating mode of the device as a test cycle. The focus of the tests was particle number concentration and soot composition. The results of the particle number concentration showed that renewable fuel content significantly reduces the number concentration of the emitted particles (9.56 × 108 #/cycle for E10 vs. 1.65 × 108 #/cycle for E100), while B7 causes a significantly higher number of emissions than E10 (3.92 × 1010 #/cycle for B7). Based on the elemental analysis, most deposits are elemental carbon, but non-organic compounds are also present. Carbon (92.18 m/m% for E10), oxygen (6.34 m/m% for E10), fluorine (0.64 m/m% for E10), and zinc (0.56 m/m% for E10) have been found in the largest quantity of deposits taken form the combustion chamber.

Open Access: Yes

DOI: 10.3390/inventions9010013