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Publications - 6515

Prediction of Efficiency, Performance, and Emissions Based on a Validated Simulation Model in Hydrogen–Gasoline Dual-Fuel Internal Combustion Engines

Zoltán Weltsch Krisztián Kun Bálint Szabó Attila Kiss

Publication Name: Energies

Publication Date: 2024-11-01

Volume: 17

Issue: 22

Page Range: Unknown

Description:

This study explores the performance and emissions characteristics of a dual-fuel internal combustion engine operating on a blend of hydrogen and gasoline. This research began with a baseline simulation of a conventional gasoline engine, which was subsequently validated through experimental testing on an AVL testbed. The simulation results closely matched the testbed data, confirming the accuracy of the model, with deviations within 5%. Building on this validated model, a hydrogen–gasoline dual-fuel engine simulation was developed. The predictive simulation revealed an approximately 5% increase in overall engine efficiency at the optimal operating point, primarily due to hydrogen’s combustion properties. Additionally, the injected gasoline mass and CO2 emissions were reduced by around 30% across the RPM range. However, the introduction of hydrogen also resulted in a slight reduction (~10%) in torque, attributed to the lower volumetric efficiency caused by hydrogen displacing intake air. While CO emissions were significantly reduced, NOx emissions nearly doubled due to the higher combustion temperatures associated with hydrogen. This research demonstrates the potential of hydrogen–gasoline dual-fuel systems in reducing carbon emissions, while highlighting the need for further optimization to balance performance with environmental impact.

Open Access: Yes

DOI: 10.3390/en17225680

Cyanobacteria-Fungi Co-Cultures: Which Partner Contributes to Antifungal Activity?

B. Pap Gergely Maróti Vince Ördög Wendy A. Stirk Johannes van Staden

Publication Name: Current Microbiology

Publication Date: 2024-11-01

Volume: 81

Issue: 11

Page Range: Unknown

Description:

Cyanobacteria synthesize secondary metabolites with antifungal activity, making them potential biopesticide agents for sustainable, eco-friendly agriculture. Programmes to identify Cyanobacterial strains with effective bioactivity generally screen strains maintained in culture collections. These strains are often monoclonal but non-axenic and this may potentially influence the bioactivity of the generated biomass. The present study investigated in vitro antifungal activity of Nostoc muscorum MACC-189 and N. linckia MACC-612 strains co-isolated with fungal co-partners and maintained in the Mosonmagyaróvár Algal Culture Collection (MACC). The fungal co-partners were isolated from the Cyanobacterial stock cultures and identified as Purpureocillium lilacinum and Sarocladium sp., respectively. The cultures were tested against seven phytopathogens. The phytopathogenic fungi were grown on potato dextrose agar plates and suspension cultures of the Cyanobacteria-fungi and isolated fungal co-partners were placed in the centre of the plate. Antifungal effects were assessed semi-quantitatively after 10 days of incubation. The Cyanobacteria-fungal co-cultures had antifungal activity against Monilinia fructigena and Aspergillus sp. with the N. muscorum/P. lilacinum culture being the most effective. The fungal isolates inhibited M. fructigena with P. lilacinum having a dose-dependent response but did not inhibit Aspergillus sp. This suggested that the antifungal effect of the Cyanobacterial cultures on M. fructigena was due to the fungal partner rather than the cyanobacterium while the antifungal effect on Aspergillus sp. was due to the cyanobacterium partner. As it was not possible to maintain living axenic N. muscorum and N. linckia cultures, this could not be conclusively confirmed. These results highlight the importance of either using axenic cultures or identifying the co-isolates when testing Cyanobacteria cultures for antifungal bioactivity.

Open Access: Yes

DOI: 10.1007/s00284-024-03914-3

Foreign trade relations of Hungary with China: A global value chain perspective

Magdolna Sass Krisztián Koppány Shulei Bi Gáspár Tamás

Publication Name: Society and Economy

Publication Date: 2023-09-15

Volume: 45

Issue: 3

Page Range: 229-249

Description:

Trade analysis for open economies is strategically important. Even though Hungarian trade relations are oriented towards the EU, the direct and indirect influence of Asia, mainly China, needs special attention. The paper focuses on direct bilateral relations between Hungary and China. The global value chain perspective enables the research to detect inter- and intra-industry dependencies and unfold and compare the industry focuses and dynamics of backward and forward linkages between 2000 and 2018. We used a mixed methodology, combining input-output analysis with company case studies based on a wide range of literature both from Chinese and East-Central European researchers. The findings support the significance of global value chain relations, highlight the restructuring of Hungarian trade relations with China over the past twenty years, and indicate the strong concentration of relations in terms of the number of companies.

Open Access: Yes

DOI: 10.1556/204.2023.00018

From ESG to holistic value addition: Rethinking sustainable investment from the lens of stakeholder theory

Glenn W. Muschert Gagan Deep Sharma Gaurav Talan Vijay Pareira

Publication Name: International Review of Economics and Finance

Publication Date: 2024-11-01

Volume: 96

Issue: Unknown

Page Range: Unknown

Description:

Stakeholder theory calls for effective stakeholder management in the interest of sustainable businesses. Whilst there is a need to redefine ‘stakeholders’, investors (i.e. shareholders) can play an essential role in bringing a paradigm shift in shaping current business practices. In recent times, the ‘Environment, Society and Governance’ (ESG) approach has emerged as an alternative form of investment for key investors seeking change. However, certain deficiencies have been identified when it comes to ESG strategies, which have led to disagreements among sustainable investors. To plug this gap and overcome this challenge, we propose an alternative framework based on sustainable business practices that holistically adds value that is inclusive of all stakeholders. To this end, we conducted semi-structured interviews with social entrepreneurs, academics, and experts from the financial services industry in an emerging country context, namely India. Based on our text analysis of interview data, we propose a ‘Holistic Value Addition’ (HVA) framework of sustainable investment that builds on value-addition by businesses towards its stakeholders. We envisage that adoption of this framework will help sustain the sustainable agenda.

Open Access: Yes

DOI: 10.1016/j.iref.2024.103530

The Effects of a Cyberbullying Intervention Programme Among Primary School Students

Helga Judit Feith Máté Kapitány-Fövény Johanna Takács Ágnes Lukács J András Falus Zsuzsanna Soósné Kiss

Publication Name: Child and Youth Care Forum

Publication Date: 2023-08-01

Volume: 52

Issue: 4

Page Range: 893-911

Description:

Background: With the increase of cyberbullying, several intervention programmes have been created that aim at reducing cyber-victimisation and perpetration. Objective: Our study presents the effects of the STAnD anti-cyberbullying programme with peer-education both on the short and the long run among lower and upper primary school students, with a focus on the participants’ cyberbullying roles. Method: The sample comprised of 536 students who participated in the intervention programme, involving 36% lower and 64% upper primary school students. Participants were measured by a self-reported questionnaire before and right after the programme, then six months later. Results: The main effect of the STAnD programme was a positive change in the participants’ willingness to engage in help-seeking and their active-defending reaction, although this effect decreased after six months. The changes were larger among lower primary school students compared to upper primary school participants. Conclusion: Our results imply that long-lasting and intensive health promotion programmes are necessary to reach a long-term intervention effect. Anti-cyberbullying programmes should take into consideration participants’ involvement and roles in cyberbullying. As our study was a non-randomised uncontrolled study design, thus interpretation of the effectiveness of the programme is limited.

Open Access: Yes

DOI: 10.1007/s10566-022-09714-9

Resources curse and sustainable development perspective: Fresh evidence from oil rich countries

Laszlo Vasa Wadim Strielkowski Yanwu Yang Zhun Zheng Alexander Lisovskiy

Publication Name: Resources Policy

Publication Date: 2023-08-01

Volume: 85

Issue: Unknown

Page Range: Unknown

Description:

In recent years, many regions that are rich in natural resources have fallen behind other countries that have fewer natural resources in terms of economic growth. This study examines the role of resource rents on national income of Arab world over the period of 1989–2021. We use mineral and oil rents to capture the resource rents. In order to determine the long-term effects of resource rents on the national income of the Arab world, this study employs the econometric methods of DOLS and FMOLS. In addition to that, the FMOLS approach, which is an asymptotically unbiased and effective estimator, is utilized throughout this study. These approaches can help to address some of the issues that arise in the analysis of time series data, is used in this study to control for endogeneity as well as serial correlation. We find that oil rents are harmful for economic growth, which approves the resource curse phenomena in case of Arab world. The abundance of natural resources in the Arab world could persuade its officials to spend more money on consumption and less on investments in physical capital, which would be detrimental to economic progress. Moreover, reliance on natural resources can lead to a scenario known as the Dutch Disease.

Open Access: Yes

DOI: 10.1016/j.resourpol.2023.103698

Lack of Collaboration on the CEP Market and the Underlying Reasons—A Systematic Literature Review

Edit Süle László Buics Csilla Bartucz

Publication Name: Sustainability Switzerland

Publication Date: 2023-07-01

Volume: 15

Issue: 13

Page Range: Unknown

Description:

The scientific community has been addressing the topic of last-mile delivery for years. To improve parcel delivery efficiency, a variety of different technologies have been created. Over the past 15 years, the focus has shifted from the operational efficiency of the individual organization to restoring sustainability and making cities more livable. As a result of the increased environmental burden, governments are enacting a growing number of restrictive measures, which will intensify economic challenges. To remain competitive, more cost-effective solutions are required. The goal of this article is to examine the significance of collaboration between CEP partners based on scientific interest, with the help of a systematic literature review. This examination is important since, despite the fact that working together with other service providers and competitors could be a favorable option for last mile suppliers looking to improve their efficiency, results show little interest in this approach. Although this strategy appears straightforward due to the potential financial and environmental benefits, there are only a few examples of collaboration in the field of last mile parcel delivery according to the results of the review. Since cooperation seems to be an inevitable operating model of the CEP market in the future, it is of utmost importance for scientific research to investigate the factors hindering the development of cooperation.

Open Access: Yes

DOI: 10.3390/su151310361

Damping of Dry Sand in Resonant Column-Torsional Simple Shear Device

Majd Ahmad Richard Ray

Publication Name: Sustainability Switzerland

Publication Date: 2023-07-01

Volume: 15

Issue: 14

Page Range: Unknown

Description:

The damping ratio values of three different Danube sands were measured in the Resonant Column-Torsional Simple Shear device (RC-TOSS). The distinctive configuration of the RC-TOSS device employed in this investigation enabled the performance of both tests using a single sample. This research estimates and compares the damping ratio values measured with three distinct methods (two of which are in the RC test): The Free Vibration Decay (FVD), the Steady-State Vibration (SSV) methods, and the method of calculating the damping ratio from the hysteretic loops generated in the TOSS test. Both dense and loose samples were tested up to a peak-to-peak amplitude shear strain of 1%. The device provides measurements over a wide range of shear strain amplitudes. The results support the employment of the SSV methods at low strains (below 0.005%), while the FVD method gives a better estimate at higher strains (above 0.03%). The two methods and the TOSS results are in agreement with each other between 0.005% and 0.03%. The effect of the number of cycles on the damping ratio was investigated where a significant decrease was observed in the damping ratio with an increasing number of cycles. A parameter is introduced to describe the rate of this decrease, which should be considered during the structural design to reduce maintenance and life-cycle costs and enhance sustainability.

Open Access: Yes

DOI: 10.3390/su151411060

Public perception of autonomous vehicles acceptance in Hungary

Balázs Horváth Dilshad Mohammed

Publication Name: International Review of Applied Sciences and Engineering

Publication Date: 2024-10-25

Volume: 15

Issue: 3

Page Range: 435-447

Description:

The integration of Autonomous Vehicles (AVs) into our modern society hinges on gaining widespread acceptance from potential road users. To indicate the preparedness of these road users and elucidate their perspectives regarding the use of AVs in future, it is imperative to conduct surveys gauging public acceptance and satisfaction with this emerging mode of transportation. This paper reports the results of a comprehensive questionnaire study involving 1,000 individuals in Gyor City. The survey's primary objective was to assess participants' attitudes and willingness to embrace autonomous vehicles within the city's road networks. The study delved into various socio-demographic factors, such as age, gender, and employment status, while also exploring participants' prior knowledge and opinions regarding the advantages and limitations of AVs. The findings reveal a generally favorable disposition among the public toward the inclusion of AVs in urban traffic, paving the way for the acceptance of mixed traffic patterns. Notably, respondents in younger age groups exhibit greater enthusiasm for incorporating AVs into their daily transportation, whereas individuals aged 65 and above express more reservations, displaying a conservative outlook. Furthermore, participants with prior knowledge and a deeper understanding of AVs exhibit a markedly more positive inclination toward this emerging technology compared to those lacking such familiarity.

Open Access: Yes

DOI: 10.1556/1848.2024.00769