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Found 6273 publications

Institutional factors and environmental performance: Insights from global economies

Cristian Barra Pasquale Marcello Falcone

Publication Name: Economic Systems

Publication Date: 2025-01-01

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

This study investigates how institutional quality, democratic governance, political orientation and economic policy uncertainty influence environmental performance across different economies globally. Even if there is literature that highlights the importance of strong institutions and democracy for environmental outcomes, empirical evidence remains inconsistent. Using data from 130 countries between 1996 and 2018, we apply a two-stage approach: first, estimating environmental performance via a stochastic frontier, and then analyzing institutional factors with a FEGLS regression and time lags to address endogeneity. The results reveal that strong institutional quality significantly improves environmental performance (β = 0.032), with its impact amplified in countries with medium and high levels of democracy (interaction terms: β = 0.012 and β = 0.010, respectively). While democracy alone exerts a mixed effect, the presence of robust institutions offsets the negative influence of economic policy uncertainty (β = −0.0273). This study provides new insights into the interplay between institutional quality and governance in fostering environmental sustainability. It also offers policy implications for achieving a balance between economic growth and ecological preservation.

Open Access: Yes

DOI: 10.1016/j.ecosys.2025.101364

The Holy Trinity of Patents, Biotechnology and Sustainability. Review of Biotech Patents in the Scope of US Patent Case Law

Barna Arnold Keserű Máté Frank

Publication Name: Chemical Engineering Transactions

Publication Date: 2024-01-01

Volume: 114

Issue: Unknown

Page Range: 985-990

Description:

Patent law plays a crucial role in all three pillars of sustainable development. Economically, patents serve as a highly valuable competitive tool, socially, they promote advancements that benefit public health and nutrition, and environmentally, patents facilitate the development and dissemination of environment-friendly technologies. In recent decades, biotechnology has emerged as one of the most significant patent-intensive industries. This paper examines the evolution of the patentability of biotechnological inventions from the early 1970s to the present day, with a primary focus on the case law of the United States, a predominant actor in this field. The main contributions of this paper are twofold. First, it explores the framework of patentability for biotechnological inventions, particularly focusing on different genomes. Second, the paper considers the potential future of biotechnology, particularly in light of ongoing litigation over CRISPR-Cas9 gene-editing technology. The findings suggest that recent US case law, particularly regarding CRISPR-Cas9, will shape patentability criteria and market access. Over-protection of biotechnology may hinder the fulfillment of sustainable development goals, while the lack of exclusive rights would hold back innovation, which is also harmful to these goals.

Open Access: Yes

DOI: 10.3303/CET24114165

Benchmark Analysis of Plastic Strain-Based Lifetime Estimation Fatigue Models in Aspect of SMD Component Standoff Height

Ambrus Zelei Antal Bakonyi

Publication Name: Advances in Transdisciplinary Engineering

Publication Date: 2024-01-01

Volume: 59

Issue: Unknown

Page Range: 128-134

Description:

Thermomechanical fatigue is one of the most common cause of the failure in microelectronic technology in the solder joints. The lifetime prediction for microelectronic components is a very important area in nowadays automotive industry, because the lifetime estimation fatigue models in the literature differ in their results by orders of magnitude. However, developing an accurate lifetime estimation methodology for microelectronic components is not straightforward, because the failure mechanism of the solder joints under cyclic thermomechanical load is not fully understood. In addition, there are numerous tolerances and uncertainties during the designing and manufacturing processes, such as component size, copper pad area, solder material volume or the formed standoff height of the component from the copper pad. These parameters can hugely affect the lifetime of the solder joint. In this paper a benchmark analysis based on finite element method were carried out with four plastic strain-based fatigue models to understand the impact of the standoff height to the estimated lifetimes. Three CAD models were created with identical parameters, except the standoff height of the components. Creating the solder geometries for the 3D models, Surface Evolver software were used. The result shows that the fatigue models give the same tendencies varying the standoff height values. However, changing the standoff height increases the differences between models, even if they are tuned so that the estimated lifetime matches for a certain standoff height.

Open Access: Yes

DOI: 10.3233/ATDE240536

Linear Quadratic Robust Control of Synchronous Reluctance Motor †

Zoltan Nemeth Dávid Gábor Bányai

Publication Name: Engineering Proceedings

Publication Date: 2024-01-01

Volume: 79

Issue: 1

Page Range: Unknown

Description:

Synchronous reluctance motors (SynRMs) play a key role in modern vehicles as they do not require permanent magnets and sliding brushes, reducing maintenance requirements and increasing reliability. My research focused on the development of robust torque control for SynRM. In the simulations, I compared the linear quadratic (LQ) controller with the conventional proportional–integral (PI) controller. To apply the LQ control method, I converted the nonlinear motor model into a linear one. We expect the results of this research to show that the LQ controller provides faster and more robust performance than the PI controller. LQ control can provide faster response times and a more stable operation, which are particularly important under dynamic vehicle operating conditions. Although LQ control is more computationally intensive and takes longer to fine tune, the results show that it results in a better and more stable control system. Such benefits are significant in dynamic vehicle operating conditions where fast and reliable torque control is essential. Overall, it can be concluded that advanced control techniques such as LQ can contribute to increasing the efficiency and performance of synchronous reluctance motors in the automotive industry, thus contributing to the development of sustainable and reliable vehicles.

Open Access: Yes

DOI: 10.3390/engproc2024079003

Seismic Performance and Sustainability of Reinforced Concrete Buildings: a Comprehensive Assessment

Nurullah Bektaş Samuel Alexandro Silitonga

Publication Name: Chemical Engineering Transactions

Publication Date: 2024-01-01

Volume: 114

Issue: Unknown

Page Range: 781-786

Description:

Recent earthquakes such as the 2023 Türkiye-Syria, Morocco, and Afghanistan, 2015 Gorkha Nepal, and 2009 Indonesia earthquakes have demonstrated the vulnerability of existing building stock. Throughout Europe, many existing buildings were constructed considering low or moderate standards or without considering them. This study investigates the seismic performance of reinforced concrete (RC) buildings, exemplified as a six-story RC dormitory building, focusing on various support and foundation conditions, soil characteristics, and site seismicity scenarios representing the seismicity of Europe. The research aims to assess the potential effects of exceeding anticipated site seismic intensities, potentially leading to safer communities and infrastructure in the face of impending earthquakes. Robot Structural Analysis Professional software is used for structural analysis and design throughout soil-structure interactions and site seismicity considerations. Moreover, this study investigates the environmental implications of RC buildings, which represent the future building inventory in Europe. It examines the varying material usage required to design structures compliant with Eurocode standards through a life cycle analysis. The methodology employed in this investigation aligns with the core principles of practical design encompassing economic and environmental sustainability. The study's key findings indicate that increasing member size can enhance performance at lower intensities, but this may not be a sufficient strategy at higher intensities, where shear walls may be necessary in high seismic zones. Sustainable design necessitates a balance between material use, performance, and environmental impact.

Open Access: Yes

DOI: 10.3303/CET24114131

A LiDAR-based approach to autonomous racing with model-free reinforcement learning

Gergely Bári Gergely Hajgató Máté Hell Ármin Bogár-Németh

Publication Name: IEEE Intelligent Vehicles Symposium Proceedings

Publication Date: 2024-01-01

Volume: Unknown

Issue: Unknown

Page Range: 258-263

Description:

This paper explores the use of reinforcement learning (RL) in the context of autonomous vehicle racing, specifically focusing on the F1TENTH simulation platform. While commercial autonomous driving often employs classic control algorithms, the state-of-the-art solutions, including those in the F1TENTH domain, increasingly rely on RL. Notably, RL-based approaches have shown superhuman performance in simulated environments, as seen in drone racing and the recent achievement by Sony in autonomous racing. In this paper we propose a novel LiDAR-only observation for learning vehicle dynamics, and test it with a widely accessible model-free RL method. The trained agent demonstrates the capability to transfer its driving skills to previously unseen tracks. Additionally, the paper provides recommendations for selecting hyperparameters, contributing valuable insights for newcomers to the field of autonomous racing.

Open Access: Yes

DOI: 10.1109/IV55156.2024.10588613

Energy-Based Approach on Calculating Stand-Off Height of Different Solder Joints

Ambrus Zelei Antal Bakonyi

Publication Name: 2024 IEEE 10th Electronics System Integration Technology Conference Estc 2024 Proceedings

Publication Date: 2024-01-01

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

In the lifetime prediction simulations of microelectronics solder joints, the stand-off height and misalignment parameters are founded on a variety of estimation methods from very simple to complex approaches. However, the stand-off height and misalignment play essential role in the lifetime of solder joints. Thus, a reliable lifetime simulation requires proper solder geometry model. Many researchers calculate the solder geometry with the software called Surface Evolver, which minimizes the total energy, including the surface tension energy. Some of these studies used energy-based methods for the stand-off height prediction. The first hypothesis is that by changing the predefined value of stand-off height in the Surface Evolver simulation, we gain different total energy values and by differentiating the energy with respect to the stand-off height, we can obtain the vertical force and a nonlinear spring characteristic for the molten solder. Similar results can be found in the literature for BGA. Secondly, it is hypothesized that this spring-like behaviour is observable in horizontal direction too, which is related with the misalignment of the component. The presented approach provides a simple model for the prediction of the stand-off height and misalignment.

Open Access: Yes

DOI: 10.1109/ESTC60143.2024.10712056

Combined Effect of Nano Ferrite and Nano Silica on Properties of Cement Mortar

Rasha R. Rawdhan Azhar J. Bohan Ghaed K. Salman Muhanad Al-Jubouri

Publication Name: International Journal of Integrated Engineering

Publication Date: 2024-01-01

Volume: 16

Issue: 1

Page Range: 350-360

Description:

This study investigates the effects of adding nano-ferrite (N.F.) and nano-silica (N.S.) on the mechanical and biological properties of mortar. By assessing four water-to-cement ratios (1–4%), the ideal nanoparticle doses were determined. Results indicated that both N.F. and N.S. significantly increased the mortar’s strength at ratios between 1% and 4%, while combinations of N.F. and N.S. improved strength up to 3% and 4% substitution, respectively. The mechanisms of strength enhancement were attributed to nanoparticles acting as fillers and hydration accelerators, which densify the mortar microstructure and promote the production of calcium silicate hydrate (C-S-H) gels. In terms of biological properties, the study examined the antibacterial effects of nano-silica and nano-ferrite. Nano-silica demonstrated greater antibacterial potency against all bacterial strains assessed. Both materials exhibited a stronger antibacterial impact on Gram-positive bacteria (Staphylococcus aureus) compared to Gram-negative bacteria (Escherichia coli), due to differences in cell wall structures. The study emphasizes the importance of optimal nanoparticle dosages and identifies limitations that warrant further research, such as durability and potential downsides at higher concentrations. Despite these challenges, the findings underscore the potential of nanoparticles to enhance mortar performance and suggest promising applications in construction and the development of antibacterial materials. Future research should focus on overcoming these constraints and exploring the practical applications of nanoparticle-enhanced mortar in real-world scenarios.

Open Access: Yes

DOI: 10.30880/IJIE.2024.16.01.030

Comparison of Mechanical Properties of PLA-Based Biocomposites Filled with Different Agricultural By-Products

László Lendvai Tej Singh Sándor K. Jakab

Publication Name: Advances in Transdisciplinary Engineering

Publication Date: 2024-01-01

Volume: 59

Issue: Unknown

Page Range: 486-493

Description:

In this study, biopolymer composites were developed using poly(lactic acid) (PLA) as a polymer matrix. Various agricultural by-products, including flax seed meal, rapeseed straw, and mustard seed meal, were added as a reinforcement. The research aimed to provide insight into the valorization of cheap, readily available residues generated in the agricultural industry and assess the mechanical properties of composites prepared using them. The experimental fabrication was conducted by compounding PLA with agro-waste particles in 10 and 20 wt% concentrations. These components were melt mixed with a twin-screw extruder and injection molded into standardized forms. The resulting fabricated composites were tested for tensile and flexural mechanical properties and hardness. Through scanning electron microscopy, images of the natural particles were taken to better understand their structure, geometry, and possible ways of interaction between them and the PLA matrix. The results of quasi-static mechanical tests suggest that using agricultural by-products can effectively improve Young's modulus and flexural modulus of PLA but at the cost of tensile and flexural strength, which decreased with the by-products' introduction. Of the three agro-waste options, rapeseed straw emerged as the superior choice because it only marginally reduced the mechanical strength of the PLA and enhanced its stiffness the most. Hardness was the least affected property, test results showed that the added fillers did not substantially change the polymer matrix's hardness.

Open Access: Yes

DOI: 10.3233/ATDE240584