The expansion of road networks, taken place during the last decades, was driven by technological progress and economic growth. The most innovative products of this trend—modern motorways and international road corridors—provide an excellent level of service, traffic safety and necessary information to travelers. However, despite this undeniable progress, major impediments and respective challenges to road authorities and operators still remain. The present paper analytically presents the main current challenges in the road engineering field, namely: a) financing new projects, b) alternative energy resources, especially renewable energy, c) serviceability, including maintenance of road infrastructure, traffic congestion and quality of the network, d) climate change hazards due to greenhouse gas emissions increase, e) environmental impacts, f) safety on roads, streets and motorways, and g) economy and cost-effectiveness. In each country and over each network, challenges and concerns may vary, but, in most cases, competent authorities, engaged in road development policies, have to deal with most of these issues. The optimization of the means to achieve the best results seems to be an enduring stake. In the present paper, the origin and the main features of these challenges are outlined as well as their tendency to get amplified or diminished under the actual evolving economic conditions worldwide, where growth alternates with crisis and social hardship. Moreover, responses, meant to provide solutions to the said challenges, are suggested, including research findings of Aristotle University and innovative technological achievements, to drive the transition to a more sustainable future.

Energy systems face serious difficulties due to economic policy uncertainty, which affects consumption trends and makes the shift to sustainability more difficult. While adjusting for economic growth and carbon emissions, this study examines the dynamic relationship between economic policy uncertainty and energy consumption (including renewable and nonrenewable) in China from 1985Q1 to 2023Q4. The research reveals the frequency-specific and time-varying relationships between these variables by employing sophisticated techniques such as Wavelet Cross-Quantile Correlation (WCQC) and Partial WCQC (PWCQC). Economic policy uncertainty and energy consumption do not significantly correlate in the short term; however, over the long term, economic policy uncertainty positively correlates with renewable energy consumption at medium-to-upper quantiles, indicating that it may play a role in encouraging investments in sustainable energy. On the other hand, EPU has a negative correlation with nonrenewable energy usage at lower quantiles, indicating a slow move away from fossil fuels. These results are confirmed by robustness testing with Spearman-based WCQC techniques. The study ends with policy recommendations to maximize economic policy uncertainty’s long-term impacts on renewable energy, reduce dependency on fossil fuels, and attain environmental and energy sustainability in China.

This study investigates the impact of tourism and institutional quality on environmental preservation, utilizing principal component analysis to generate three composite indices of environmental sustainability for 134 countries from 2002 to 2020. The results reveal that environmental sustainability indices have generally improved in lower- and middle-income nations but have declined in certain high-income countries. The findings also underscore the critical role of institutional quality—particularly regulatory standards, government effectiveness, anti-corruption efforts, and adherence to legal frameworks—in promoting environmental sustainability. However, the study shows that both domestic and international tourism expenditures can have adverse effects on environmental sustainability. Notably, these negative effects are exacerbated in countries with well-developed institutions, which is an unexpected outcome. This highlights the need for careful, thoughtful policymaking to ensure that the tourism sector supports sustainable development, rather than undermining environmental objectives.

In order to study the temperature change trend of the surrounding geotechnical soil during the operation and thermal recovery of the medium-deep geothermal buried pipe and the influence of the geotechnical soil on the operational stability of the vertical buried pipe after thermal recovery. Based on the data of geological stratum in Guanzhong area and the actual engineering application of medium-deep geothermal buried pipe heating system in Xi’an New Area, the influence law of medium-deep geothermal buried pipe heat exchanger on surrounding geotechnical soil is simulated and analyzed by FLUENT software. The results show that: after four months of heating operation, in the upper layer of the geotechnical soil, the reverse heat exchange zone appears due to the higher fluid temperature; in the lower layer of the geotechnical soil, the temperature decreases more with the increase of depth and shows a linear increase in the depth direction; without considering the groundwater seepage, after eight months of thermal recovery of the geotechnical soil after heating, the maximum temperature difference after recovery is 3.02 ℃, and the average temperature difference after recovery is 1.30 ℃ The maximum temperature difference after recovery was 3.02 ℃ and the average temperature difference after recovery was 1.30 ℃. The geotechnical thermal recovery temperature difference has no significant effect on the long-term operation of the buried pipe, and it can be operated continuously and stably for a long time. Practice shows that due to the influence of various factors such as stratigraphic structure, stratigraphic pressure, radioactive decay and stratigraphic thermal conductivity, the actual stratigraphic temperature below 2000m recovers rapidly without significant temperature decay, fully reflecting the characteristics of the Earth’s constant temperature body.

This paper highlights the complex relationship between entrepreneurship, sustainable development, and economic growth in 41 European countries, using a reliable K-Means cluster analysis. The research thoroughly evaluates three key factors: the SDG Index for sustainable development, GDP per capita for economic well-being, and the New Business Density Rate for entrepreneurial activity. Our methodology reveals three distinct narratives that embody varying degrees of economic vitality and sustainability. Cluster 1 comprises the financially stable and sustainability-oriented countries of Western and Northern Europe. Cluster 2 showcases the variegated economic and sustainability initiatives in Central and Southern Europe. Cluster 3 envelopes the economic titans with noteworthy business expansion but with the potential for better sustainable practices. The analysis reveals a favourable association between economic prosperity and sustainable development within clusters, although with nonlinear intricacies. The research concludes with a series of strategic imperatives specifically crafted for each cluster, promoting economic variation, increased sustainability, invention, and worldwide collaboration. The resulting findings highlight the crucial need for policy-making that considers the specific context and the potential for combined European resilience and sustainability.

This research aims to investigate how technological innovation influences social sustainability via the mediating role of organizational innovation and digital entrepreneurship. This investigation employed a quantitative research approach and used data from survey questionnaires based on a set of suppositions evaluated using structural equation modeling. A total of 320 respondent companies from digital provider companies in Thailand. The findings of the research expose that technological innovation has a positive effect on organizational innovation and digital entrepreneurship. Both serve as mediators in the correlation between technology innovation and social sustainability. Moreover, this research will be beneficial for businesses that are implementing new technologies and innovation, considering their role in attaining both environmental and social sustainability.