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Found 6278 publications
Investigation of Possibilities of λ = 1 Full Load Operation for Gasoline Engines in the Light of Future Emission Regulation
Publication Name: Periodica Polytechnica Transportation Engineering
Publication Date: 2022-01-01
Volume: 50
Issue: 2
Page Range: 111-127
Description:
To date, huge amounts of money have been invested in the development of internal combustion engines to reach the current level of technology. High specific power and good thermal efficiency have been achieved, thanks to which, internal combustion engines are now widely used. However, the driving force behind the developments is no longer the high performance, but the compliance with strict emission standards. Future emissions regulation, namely Euro 7, will be challenging for engine and vehicle manufacturers. One possible technical solution may be to use a stoichiometric air-fuel mixture on the entire engine map to meet the requirements of the Euro 7 emission standard. This article analyzes the change in Euro regulations in the light of Euro 7, as well as the theoretical background of the λ = 1 operation. Several technical possibilities to achieve the stoichiometric ratio, such as e.g. water injection or variable compression ratio are presented.
Open Access: Yes
DOI: 10.3311/PPtr.17433
Action and immunomodulatory mechanisms, formulations, and safety concerns of probiotics
Publication Name: Bioscience of Microbiota Food and Health
Publication Date: 2025-01-01
Volume: 44
Issue: 1
Page Range: 4-15
Description:
The global probiotics market has been continuously growing, driven by consumer demand for immune-enhancing functional foods, dietary supplements, and natural therapeutics for gastrointestinal and gut function-mediated diseases. Probiotic microorganisms represent a diverse group of strains with complex but generalized mechanistic patterns. This review describes the various immunomodulatory mechanisms by which probiotics exert their effects, including the competitive exclusion of pathogenic microbes, production of antimicrobial substances, modulation of the immune system, and improvement of gut barrier function. In addition, the various formulations and methods of delivery of probiotics and the safety concerns associated with these products are also discussed.
Open Access: Yes
E-government development, armed conflict, and government revenue: A cross-country panel analysis
Publication Name: Journal of International Studies
Publication Date: 2026-01-01
Volume: 19
Issue: 1
Page Range: 160-184
Description:
The growing digitalisation of public administration and the increasing number of countries affected by armed conflicts raise important questions about the role of e-government in sustaining government revenue mobilisation under institutional stress. This study examines how the development of digital government influences different sources of public revenue and whether armed conflict moderates this relationship across countries. The analysis uses cross-country panel data for 2003–2024, combining indicators of e-government development from the UN EGDI database, fiscal indicators from the World Bank Open Data, and conflict information from the UCDP/PRIO Armed Conflict Dataset, estimated using two-way fixed effects models with robust clustered standard errors. The results show that economic development is the strongest determinant of revenue mobilisation, with GDP per capita coefficients ranging from 0.95 to 1.22 across models. The overall EGDI does not demonstrate a statistically significant direct effect on tax revenue or revenue excluding grants, although weak interaction effects suggest that armed conflict may reduce the fiscal effectiveness of digital governance (−0.238; p ≈ 0.10). A significant negative relationship is observed for the telecommunications infrastructure component with tax revenue (−0.362; p = 0.005) and revenue excluding grants (−0.349; p = 0.011). For customs duties and social contributions, the results indicate no systematic relationship between e-government development and revenue performance, highlighting the dominant role of macroeconomic conditions in shaping fiscal capacity.
Open Access: Yes
Team efficacy and communication satisfaction as a driver of commitment among university entrepreneurship programme participants
Publication Name: Journal of Open Innovation Technology Market and Complexity
Publication Date: 2025-03-01
Volume: 11
Issue: 1
Page Range: Unknown
Description:
This research explores how perceived team efficacy and communication satisfaction within student teams influence team members’ commitment and willingness to continue in the context of university entrepreneurship programs. The results suggest that team communication and efficacy are influential from a commitment perspective. The research is based on the results of a quantitative survey among participating HSUP (Hungarian Startup University Program) students—a program available at all major Hungarian universities. The applied SEM modeling method provided an adequate instrument to understand better the impact of perceived team attributes on value and exchange-based commitment and identify some of these variables’ determinants. This research provides empirical evidence that the commitment of nascent student entrepreneurs, framed through project and profession focus, should incorporate a team perspective. The paper also formulates further research directions and implications for the design of university entrepreneurship programs. In addition to professional competencies (e.g., market research methods, business model building, MVP creation), the mentoring process should strengthen effective communication, team efficacy, and spirit within the entrepreneurial group. These elements significantly affect the commitment of group members, which in turn influences their willingness to continue on an individual level.
Open Access: Yes
DIGITALISATION IN ANGLING TOURISM: INTRODUCING NEW TECHNOLOGIES TO A TRADITIONAL TOURISM PRODUCT
Publication Name: Geojournal of Tourism and Geosites
Publication Date: 2025-01-01
Volume: 58
Issue: 1
Page Range: 42-51
Description:
In recent years, the use of digital solutions in tourism has accelerated and smart solutions are now used even in areas that are less technology-oriented, such as angling tourism. Angling itself and angling tourism seem rather traditional, definitely not tech-savvy activities, ones that can be categorised among the ecotourism or slow tourism products. It is not to say, however, that angling tourism does not evolve and is immune to the trends released in tourism. Recently there were huge changes in the regulation and organisation of angling in Hungary (and further changes are expected to come), which brought about a surge in the number of anglers in Hungary and the development of angling tourism. By now angling has become by far the hobby in Hungary done by the largest number of people; after a steady growth for decades, the number of registered anglers has by now reached almost one million persons, i.e. approximately ten per cent of the Hungarian population are anglers (and so potential target group of angling tourism), which makes the investigation of the topic of angling tourism really important – not to mention the fact that not only domestic but also inbound angling tourism is characteristic of Hungary. Among the changes, in 2019 the electronic support of angling administration was launched through the so-called HORINFO system run by MOHOSZ, the Hungarian National Angling Association. This paper summarises the changes and their consequences, explores the current digitalisation of angling tourism, its benefits, and examines the acceptance of new technologies by anglers. The results of the research show that the digitalisation and the introduction of new technologies accelerated during the Covid-19 epidemic, but their adoption by angling tourism has been slower. The study shows the importance of digitalisation in monitoring the environmental pillar of sustainability and the interventions needed. The study also provides a thorough investigation of the Hungarian and international literature of angling tourism, rather deficient to date, and gives recommendations on the further development of the HORINFO system. The significance of the issue is enhanced by the fact that Hungary now has a National Angling Development Strategy to strategically found further angling tourism developments.
Open Access: Yes
Community transport experiences, in connection with diesel-LPG mixed operation buses belonging to the category of heavy vehicles
Publication Name: International Journal of Heavy Vehicle Systems
Publication Date: 2025-01-01
Volume: 32
Issue: 2
Page Range: 137-162
Description:
Various international literature sources and papers address the issue of the theoretical implementation of using liquefied petroleum gas (LPG) gas as catalyst material injected into the carburetor system of diesel engines and its positive impact on the characteristic features of the engine and its emission. In Europe, for example, Landi-Renzo, one of the biggest Italian companies dealing with traditional gas systems, is developing a compressed natural gas (CNG)-diesel system. The present paper outlines the operational characteristics of a diesel-LPG dual operating system based on our own experiments and measurements which have been carried out on the transformed buses of the Southern Transdanubian Transportation Centre (DDKK, Hungary). In the process of evaluation two aspects were taken into consideration: the impact on emission and that on fuel consumption. Of course, the tests can be extended to wider areas, which take into account both vehicle structures and the environment (Palkovics and El-Gindy, 1993; Palkovics et al., 1996; Shokouhfar et al., 2016).
Open Access: Yes
Vibration levels of stacked automotive engine rack in truck shipments as a function of vehicle speed and road condition
Publication Name: Journal of Testing and Evaluation
Publication Date: 2020-01-29
Volume: 49
Issue: 1
Page Range: Unknown
Description:
In the past three decades, there has been a tremendous global shift in the use of returnable or reusable packaging in the automotive industry. This article focuses on the physical vibration forces that occur in a very important type of package system designed for engines and transmissions, namely the steel racks that have vertical posts on the four vertical edges that allow higher return ratios when empty. Engines and transmissions require zero damage acceptance levels today, as they are mated at the end of the assembly process, and they need to function 100 % of the time as the vehicle rolls off the finish line. They also are the most expensive components of the vehicle. This study was conducted to investigate the vibration environment of the stacked engine rack during truck transportation with various truck speeds, road conditions, and other road characteristics, such as speed bumps and railway crossings. Triaxial acceleration data were collected both on the truck floor as well as on the stacked racks themselves to determine the differences of vibration levels from truck floor to the stacked rack where vibration intensity increased. This study found that there were significant vibration severities in the stacked racks in all three orientations.
Open Access: Yes
DOI: 10.1520/JTE20180782
Advances in Standardised Battery Testing for Enhanced Safety and Innovation in Electric Vehicles: A Comprehensive Review
Publication Name: Batteries
Publication Date: 2025-04-01
Volume: 11
Issue: 4
Page Range: Unknown
Description:
Standardised battery tests are essential for evaluating the safety, reliability, and performance of modern battery technologies, especially with the rapid emergence of innovations such as solid-state and lithium–sulphur batteries. This review reveals critical shortcomings in current international standards (e.g., IEC, IEEE, SAE), which often do not keep pace with technological developments and are not harmonised across regions, limiting their effectiveness in real-world applications. The paper stresses the need for the continuous review of test protocols through collaboration between researchers, manufacturers, and regulators. A detailed case study of the BYD Dolphin battery demonstrates the practical importance of comprehensive testing in real-world conditions, spanning electrical, thermal, and mechanical ranges. The review concludes that up-to-date, harmonised, and scenario-specific test methods are needed to ensure accurate battery assessment, support global comparability, and enable the safe introduction of next-generation batteries for electric mobility and energy storage. Future work should prioritise operational monitoring, open access data sharing, and the development of sustainability-focused practices such as recycling and reclamation.
Open Access: Yes
Waste Management Policy in Four ASEAN Countries: Emerging Contemporary Issues from Research Works
Publication Name: Forum Geografi
Publication Date: 2025-01-01
Volume: 39
Issue: 2
Page Range: 274-291
Description:
Southeast Asia faced an urgent waste crisis, particularly in Indonesia, Malaysia, Thailand, and the Philip-pines, threatening severe environmental, ecosystem, and public health consequences. Without a comprehensive waste management policy, conditions deteriorated significantly. This research explored waste management policy studies with a bibliometric lens in four Southeast Asian countries: Indonesia, Thailand, Malay-sia, and the Philippines. Using the Scopus database, powered by the VOSViewer software and the biblio-metrix-R studio package, this research provided a precise visualization. The findings revealed that four countries exhibited an upward yet fluctuating trend in publication output, with Indonesia emerging as the leading contributor in recent years. Furthermore, most documents studied by scholars, the highest impact documents, and most documents in journal sources were also discussed. Two affiliates in Malaysia were the leading affiliates, followed by two affiliates from Thailand. Moreover, environmental science and social science were areas of interest for scholars. Term network trajectory mapping and thematic maps were comprehen-sively included. In sum, Indonesia fought hard against plastic waste to minimize climate change, while Malaysia focused on addressing waste emissions and household waste. The Philippines sought to raise awareness about the microplastic problem in the ocean and promote public awareness of waste management. Thailand requires attention to financing waste management equipment, implementing environmentally friendly solutions, and revising waste management rules. Its implications underlined a new complex of waste issues in Southeast Asia, requiring adapted strategies and solutions to address each country’s waste challenges and concerns. Current research contributed to the existing state-of-knowledge by providing disaggregated views of national waste management policy in those countries. It also highlighted key potential future hotspots for targeted interventions and resource allocation; thus, future policies and collaborations in waste management might have become more effective and impactful.
Open Access: Yes
