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Found 6334 publications

Sustainability implications of lateral wander modes for autonomous trucks

Csaba Koren Richárd Nagy Mohammad Fahad

Publication Name: Discover Applied Sciences

Publication Date: 2024-03-01

Volume: 6

Issue: 3

Page Range: Unknown

Description:

Autonomous trucks can bring changes in transport infrastructure in terms of sustainability based on the type of lateral wander mode used. In this research, two lateral wander modes, a zero wander and uniform wander mode are analyzed based on their applicability for sustainability by analyzing the CO2 emissions occurred during pavements life cycle. Both lateral wander modes have been analyzed in terms of occurrence of fatigue damage by using finite element analysis in ABAQUS. The fatigue damage predictions have then been used for planning the maintenance interventions for both lateral wander modes. Life cycle analysis has been performed for the analysis period of 30 years for the pavement section of 10 km. Results show that zero wander mode generates more emissions as a result of premature fatigue damage under channelized loading. The uniform wander mode leads to 20% less emissions when compared to zero wander mode. Moreover, the use of full depth reclamation during pavement’s life cycle improves the CO2 emissions by 15% when compared to traditional removal and reconstruction methods. Therefore, the uniform wander mode is favorable for improvement of pavement sustainability in terms of CO2 emissions.

Open Access: Yes

DOI: 10.1007/s42452-024-05732-5

International Trade in Food and Agro-Based Products in the Time of COVID-19

Katalin Mezei Nóra Gombköto

Publication Name: Quaestiones Geographicae

Publication Date: 2024-03-01

Volume: 43

Issue: 2

Page Range: 5-16

Description:

The aim of the study is to examine the regional impact of the COVID-19 pandemic and its individual waves on foreign trade in food and agro-based products in the world's largest trading countries. The study was based on the statistical database of the International Trade Centre (ITC). In addition to the basic analysis, use was made of the auto-correlation method to detect special relationships between foreign food trade of different countries. The results show that the pandemic has had the greatest impact on agricultural and food trade in the United States, but it has spilled over to other countries as well, especially its two major trading partners, the European Union and China. Food trade stagnated in the initial period of the pandemic, but later recovered relatively well. The six examined regions can be divided into three groups based on the typical features of their autocorrelation.

Open Access: Yes

DOI: 10.14746/quageo-2024-0016

Navigating Inflation Challenges: AI-Based Portfolio Management Insights

Tibor Bareith László Vancsura Tatay Tibor

Publication Name: Risks

Publication Date: 2024-03-01

Volume: 12

Issue: 3

Page Range: Unknown

Description:

After 2010, the consumer price index fell to a low level in the EU. In the euro area, it remained low between 2010 and 2020. The European Central Bank has even had to take action against the emergence of deflation. The situation changed significantly in 2021. Inflation jumped to levels not seen for 40 years in the EU. Our study aims to use artificial intelligence to forecast inflation. We also use artificial intelligence to forecast stock index changes. Based on the forecasts, we propose portfolio reallocation decisions to protect against inflation. The forecasting literature does not address the importance of structural breaks in the time series, which, among other things, can affect both the pattern recognition and prediction capabilities of various machine learning models. The novelty of our study is that we used the Zivot–Andrews unit root test to determine the breakpoints and partitioned the time series into training and testing datasets along these points. We then examined which database partition gives the most accurate prediction. This information can be used to re-balance the portfolio. Two different AI-based prediction algorithms were used (GRU and LSTM), and a hybrid model (LSTM–GRU) was also included to investigate the predictability of inflation. Our results suggest that the average error of the inflation forecast is a quarter of that of the stock market index forecast. Inflation developments have a fundamental impact on equity and government bond returns. If we obtain a reliable estimate of the inflation forecast, we have time to rebalance the portfolio until the inflation shock is incorporated into government bond returns. Our results not only support investment decisions at the national economy level but are also useful in the process of rebalancing international portfolios.

Open Access: Yes

DOI: 10.3390/risks12030046

Improving Flash Flood Hydrodynamic Simulations by Integrating Leaf Litter and Interception Processes in Steep-Sloped Natural Watersheds

Péter Kalicz Zoltán Gribovszki Katalin Bene Gergely Ámon R. P. Ray

Publication Name: Water Switzerland

Publication Date: 2024-03-01

Volume: 16

Issue: 5

Page Range: Unknown

Description:

More frequent high-intensity, short-duration rainfall events increase the risk of flash floods on steeply sloped watersheds. Where measured data are unavailable, numerical models emerge as valuable tools for predicting flash floods. Recent applications of various hydrological and hydrodynamic models to predict overland flow have highlighted the need for improved representations of the complex flow processes that are inherent in flash floods. This study aimed to identify an optimal modeling approach for characterizing leaf litter losses during flash floods. At a gauged watershed in the Hidegvíz Valley in Hungary, a physical-based model was calibrated using two distinct rainfall–runoff events. Two modeling methodologies were implemented, integrating canopy interception and leaf litter storage, to understand their contributions during flash flood events. The results from the model’s calibration demonstrated this approach’s effectiveness in determining the impact of leaf litter on steep-sloped watersheds. Soil parameters can estimate the behavior of leaf litter during flash flood events. In this study, hydraulic conductivity and initial water content emerged as critical factors for effective parametrization. The findings underscore the potential of a hydrodynamic model to explore the relationship between leaf litter and flash flood events, providing a framework for future studies in watershed management and risk-mitigation strategies.

Open Access: Yes

DOI: 10.3390/w16050750

Recent Changes in Hungarian Criminal Legislation to Address Irregular Migration

Robert Bartko

Publication Name: Iza Journal of Development and Migration

Publication Date: 2024-03-01

Volume: 15

Issue: 1

Page Range: 31-41

Description:

The last two decades have seen a dramatic increase in international migration, with Europe experiencing a significant influx of individuals from developing countries, especially the Near-East. This phenomenon has led to a spike in irregular migration into the European Union, reaching peak levels in the past four years, profoundly affecting both the EU and its individual member states. Hungary, facing a considerable influx of migrants in 2015, took a decisive political step by adopting specific criminal measures aimed at mitigating this irregular migration. This move resulted in notable modifications to the Hungarian legal framework, especially concerning criminal law and procedures. The Hungarian Criminal Code was expanded to include three novel offenses: the destruction of the border fence, illegal crossing of the border fence, and interference with the construction of the border fence. Furthermore, the general part of the Criminal Code underwent revisions to thoroughly address the issue of irregular migration. This study seeks to explore the adjustments made to Hungarian criminal law in response to irregular migration, focusing on the introduction of new legal definitions and examining criminal statistics from 2015 to 2017. It is important to note that the analysis is based solely on official criminal data from 2015 to 2017, as figures for 2018 were not available at the time due to ongoing consolidation by the Unified Hungarian Criminal Statistics of Investigation Authorities and Prosecution.

Open Access: Yes

DOI: 10.62693/415ebh62

Effects of Lip Length and Inside Radius-to-Thickness Ratio on Buckling Behavior of Cold-Formed Steel C-Sections

Ardalan B. Hussein Diyari B. Hussein

Publication Name: Buildings

Publication Date: 2024-03-01

Volume: 14

Issue: 3

Page Range: Unknown

Description:

Cold-formed steel (CFS) sections constructed with high-strength steel have gained prominence in construction owing to their advantages, including a high strength-to-weight ratio, shape flexibility, availability in long spans, portability, cost-effectiveness, and design versatility. However, the thin thickness of CFS members makes them susceptible to various forms of buckling. This study focuses on addressing and mitigating different types of buckling in columns and beams by manipulating the lip length (d) and the ratio of inside radius to thickness (Ri/t) in CFS C-sections. To achieve this objective, a comprehensive analysis involving 176 models was conducted through the Finite Element Method (FEM). The findings reveal that an increase in lip length leads to a corresponding increase in critical elastic buckling load and moment ((Formula presented.), (Formula presented.), (Formula presented.), (Formula presented.), (Formula presented.), and (Formula presented.)). It is recommended to utilize a lip length greater than or equal to 15 mm for both columns and beams to mitigate various buckling types effectively. Conversely, an increase in the ratio of inside radius to thickness (Ri/t) results in an increase in critical elastic local buckling load ((Formula presented.)) and moment ((Formula presented.)). Thus, lip length (d) significantly influences column and beam buckling, whereas Ri/t exhibits a relatively impactful effect. Subsequently, the experimental test results were used to verify finite element models. These insights contribute significant knowledge for optimizing the design and performance of CFS C-sections in structural applications.

Open Access: Yes

DOI: 10.3390/buildings14030587

CEO narcissism and firm's cash conversion cycle: The moderating role of CEO's gender

Gilberto Marquez-Illescas Heba F. Zaher

Publication Name: Accounting and Finance

Publication Date: 2024-03-01

Volume: 64

Issue: 1

Page Range: 783-810

Description:

This study investigates the effect of CEO narcissism on firm's cash conversion cycle (CCC), and how this influence is moderated by CEO gender. Based on a sample of 354 CEOs in 229 S&P 500 firms, our results indicate that firms led by more narcissistic CEOs tend to have a shorter CCC and this effect is weaker in companies led by a female CEO. Our additional analyses show that the effect of CEO narcissism on the CCC may improve or damage firm performance depending on the firm's CCC level.

Open Access: Yes

DOI: 10.1111/acfi.13161

A MILP approach combined with clustering to solve a special petrol station replenishment problem

Tamás Hajba Bálint Psenák Dániel Heitz Zoltán Horváth

Publication Name: Central European Journal of Operations Research

Publication Date: 2024-03-01

Volume: 32

Issue: 1

Page Range: 95-107

Description:

Vehicle routing problem is a well-known optimization problem in the logistics area. A special case of the vehicle routing problem is the station replenishment problem in which different types of fuel types have to be transported from the depots to the customers. In this paper we study the replenishment problem of a European petrol company. The problem contains several additional constraints such as time windows, different sized compartment vehicles, and restrictions on the vehicles that can serve a customer. We introduce a mixed integer linear programming model of the problem. To reduce the size complexity of the MILP model the customers are clustered and, based on the clusters, additional constraints are added to the MILP model. The resulting MILP model is tested on real problems of the company. The results show that combining the MILP model with clustering improves the effectiveness of the model.

Open Access: Yes

DOI: 10.1007/s10100-023-00849-1

Assessing Future Hydrological Variability in a Semi-Arid Mediterranean Basin: Soil and Water Assessment Tool Model Projections under Shared Socioeconomic Pathways Climate Scenarios

Aliakbar Nazari Samani Arash Zare Garizi Majid Movahedi Rad Vahid Shafaie Marziyeh Haji Mohammadi

Publication Name: Water Switzerland

Publication Date: 2024-03-01

Volume: 16

Issue: 6

Page Range: Unknown

Description:

Climate is one of the main drivers of hydrological processes, and climate change has caused worldwide effects such as water scarcity, frequent floods and intense droughts. The purpose of this study was to analyze the effects of climate change on the water balance components, high flow and low flow stream conditions in a semi-arid basin in Iran. For this reason, the climate outputs of the CanESM5 model under Shared Socioeconomic Pathways (SSP) scenarios SSP126, SSP245, and SSP585 were spatially downscaled by the Statistical Downscaling Model (SDSM). The hydrological process was simulated by the Soil and Water Assessment Tool (SWAT) model. Key findings include a 74% increase in evapotranspiration, a reduction by up to 9.6% in surface runoff, and variations in discharge by up to 53.6%. The temporal analysis of snow melting changes revealed an increase in the volume of snow melting during winter months and a reduction in the volume during spring. The projected climate change is expected to cause notable variations in high and low flow events, particularly under the SSP585 scenario, which anticipates significant peaks in flow rates. This comprehensive analysis underscores the pressing need for adaptive strategies in water resource management to mitigate the anticipated impacts of climate variability.

Open Access: Yes

DOI: 10.3390/w16060805