African air transport is expected to take off after the Single African Air Transport Market (SAATM) launch in January 2018. Unfortunately, this seems not to be the case, particularly in West Africa, where adequate direct local flight is highly difficult to find. Hence, the fundamental question is: what levers should be activated for an effective revival of this sector? This paper aims to analyze West African air transport competitiveness factors by collecting data physically through surveys in various West African airports (Abidjan, Cotonou, Accra, Lome) also by interviewing professionals in the sector (Air traffic controllers, Air Navigation Service Providers, Air transports Managers, etc.) and among others, SAATM reports to appreciate its implementation. We were able to survey 435 actors (individuals and key informants) from January to July 2023 to evaluate quality of service, airline performance, safety, customer satisfaction etc. Airline operating costs were analyzed to understand the associated bottlenecks. The results show that SAATM is not yet well implemented in all contracting states, travelers are not satisfied with the air supply (airlines, infrastructure and fares) and taxation excessively increases ticket prices. The main factors for West African air transport take-off are liberalization, taxation and infrastructure investments.

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.

This research aims to explain the management of the Cekungan Bandung Urban Area with a focus on three policy formulations, namely process, content and context in the social, environmental and economic dimensions. The research method used is a qualitative approach. Data collection techniques include observation and interviews with stakeholders, using purposive sampling techniques, including the Head of West Java Province Regional Development Planning Agency, district/city Bappeda heads, planners (Badan Perencanaan Dan Pembangunan Daerah, Bappeda), Regional People`s Representative Assembly (Dewan Perwakilan Rakyat Daerah, DPRD members), Legal Bureau and Collaboration Bureau Heads in West Java Province, and Academic Manuscript Compiler. Due to the absence of comfortable, safe, and punctual public transportation, people continue to use private vehicles, leading to unresolved traffic congestion and environmental pollution, thus resulting in economic losses. The results show the formulation of policies for managing the urban area of the Cekungan Bandung, specifically the establishment of BP Cek ban, faced challenges due to a lack of authority in managing financial and human resources. The agency couldn’t execute programs or activities and implement the development due to limitations in legal authority over state finances. Alternative policies were not effectively synchronized between government levels and lacked legislative support, hindered by regional autonomy. The contribution of the research is as reference material for the government in formulating management policies for the Cekubgan Bandung urban area.

The study examines the acceptance and sustainability of vegetarian, vegan, and flexitarian diets, focusing on the health and environmental benefits of reducing animal-derived proteins. Our objective was to investigate the level of acceptance of these dietary trends across different age groups and health statuses and understand how sustainability awareness and health consciousness impact dietary decisions. We used a mixed-method approach to achieve this, conducting eight in-depth interviews and a survey with 329 participants from various demographic backgrounds. Our qualitative analysis revealed that individual and family health consciousness, along with sustainability considerations, play a significant role in dietary choices, particularly among younger generations who are more open to sustainable eating. Quantitative results show that access to information and educational resources strongly influences dietary decisions, further supporting the spread of environmentally conscious eating habits. The practical significance of our research lies in highlighting the importance of educational campaigns and public health policies that can foster broader societal acceptance of sustainable diets. Educational institutions and community organizations can help facilitate the transfer of knowledge necessary for adopting such diets. Our findings emphasize the role of targeted communication strategies in increasing awareness of the benefits of plant-based diets. Furthermore, these insights underline the potential of policy interventions to make sustainable food choices more accessible and appealing to a wider population. Future research could focus on exploring economic incentives and examining long-term health and environmental outcomes associated with these diets.

The use of porous media to simplify the thermohydraulic of a nuclear reactor is the topic of recent research. As a case study, the rector of 200 kW installed at Missouri University of Science and Technology is modeled in this paper. To help this objective, a fundamental CFD examination was completed to supplement the neutronics investigation on the present reactor. Characteristics of thermal energy removal from a typical research reactor are modeled by numerical thermal transport in porous media. The neutron flux is modeled by the nodal expansion method. For the thermo-hydraulic part, a three-dimensional governing equation is solved by an iterative method to find the steady-state solution of fluid flow and temperature in loss of coolant condition where the heat produced in the reactor core is removed by free convection. The profiles of heat flux for various power levels are benchmarked. Pressure, temperature, and velocity contours in the power passage were assessed at 300 kW and 500 kW power levels. To reduce the computational cost, a porous media approach for the whole geometry was utilized. The numerical results agree with the experimental results. The developed model can be used for safety and reliability analysis for various loss of coolant accidents.

The carbon footprint, which measures greenhouse gas emissions, is a good environmental indicator for choosing the best sustainable mode of transportation. The available emission factors depend heavily on the calculation methodology and are hardly comparable. The minimum and maximum scenarios are one way of making the results comparable. The best sustainable passenger transport modes between Rijeka and Split were investigated and compared by calculating the minimum and maximum available emission factors. The study aims to select the best sustainable mode of transport on the chosen route and to support the decision-making process regarding the electrification of the Lika railroad, which partially connects the two cities. In the minimum scenario, ferry transport without vehicles was the best choice when the transportation time factor was not relevant, and electric rail transport when it was. In the maximum scenario, the electric train and the ferry with vehicles were equally good choices. Road transportation between cities was not competitive at all. The comparison of the carbon footprint based on minimum and maximum scenarios gives a clear insight into the ratio of greenhouse gas emissions from vehicles in passenger transport. It supports the electrification of the Lika railroad as the best sustainable transport solution on the route studied.