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The purpose of this paper is to provide an overview of the computational progress in the development of hydrogen-fired gas turbines. This review aims to identify suitable combustion models, appropriate NO_x chemistry mechanisms and NO_x emission levels for effective utilization of hydrogen as an alternative fuel in gas turbines.

Hydrogen is recognized as a potential alternative fuel for achieving exceptionally low emissions in gas turbines. The developments in conventional, trapped vortex combustor and micromix combustors are discussed, along with various computational models aimed at accurately predicting combustion and emission characteristics. The results of numerical simulations were then discussed with emphasis on their role in optimizing the combustor geometry.

Computational studies that were used to optimize the combustor geometry to reduce NO_x emissions and the flashback phenomenon are discussed. To retrofit existing gas turbines for hydrogen fuel, minor modifications that are required were discussed by analyzing extensive literature. The influence of key design and geometrical parameters on NO_x emissions and the appropriate selection of combustion models for numerical simulations in optimizing various combustion systems are elaborated.

The review emphasizes the computational studies in the progress of hydrogen-fired gas turbine developments. The previous reviews were primarily focused on the combustion technologies for hydrogen-fired gas turbines. This comprehensive review focuses on the key design parameters, flame structure, selection of combustion models, combustion efficiency improvement and impact of parametric studies on NO_x formation of various combustion systems, in particular hydrogen combustion for gas turbine applications.

The purpose of this paper is to evaluate the impact of beneficial externality generated by the World Heritage List (WHL) on residential property values in order to offer new insights into heritage discourses.

The study uses the hedonic price model to estimate empirically the difference in prices for residential properties located in the Old Rauma World Heritage. The study uses residential sales transaction data from the City of Rauma from January 2005 to September 2012 drawn from an online database called KVKL Hintaseurantapalvelu managed by the Central Federation of Finnish Real Estate Agencies.

The research results indicate a positive, but insignificant, relationship between the property sale prices (euros/sqm) and heritage designation. However, the total sale prices are higher in Old Rauma as the properties are significantly larger in Old Rauma compared to other properties in Rauma.

Studies in heritage economics have assessed the influence of the property market on heritage listing and designation at either the national level, the local level or a mix of national/local levels. This paper contributes to the literature by analysing the impact of a United Nations Educational, Scientific and Cultural Organisation (UNESCO) world heritage designation on residential property values. UNESCO is the leading global institution which deals with the protection of heritage sites that transcend national and local boundaries.

The World Heritage Convention has reached a milestone, and this year, in 2022, it is celebrating its 50th anniversary. The aim of this article is to review whether and how the goals of the strategic action plan (SAP) for the Implementation of the World Heritage Convention (2012–2022) have been reached.

This article starts by considering the outcomes for three of the SAP goals, dealing with protection and management; the credibility of the World Heritage List and sustainable development, using additional information from the final implementation report of the SAP (UNESCO, 2021a), which provides key performance indicators and the implementation status for each goal and associated outcomes. This article then compares and contrasts available data, trends and examples to provide more in-depth analyses of the implementation of the three goals. Data have been gathered from my own research and from the work of other academics and practitioners.

The article finds several key positive changes, including the recent revisions of the Operational Guidelines to include provisions from the 2015 UNESCO Policy on World Heritage and Sustainable Development. However, a number of concerning or worsening trends relating to the protection and management of the World Heritage List, its increasing lack of credibility and sustainable development make it difficult to conclude that the implementation of the goals has been positive. The article concludes with suggestions for addressing these issues.

This paper fills a gap, as not much has yet been published on the state of implementation of the Convention at 50 years old.

The purpose of this study is to propose a new magnetic gearing device and the proposed transmission model can be applied in the field of wind power and wave energy generation gearboxes.

A novel radial differential field-modulated two-stage magnetic gear is introduced, using a unique radial differential linkage to integrate two single-stage magnetic gears. This design incorporates a magnetic isolation ring to enhance transmission efficiency by minimizing magnetic interference and preventing power circulation. The two-stage modulating ring rotor operates synchronously via a connecting bridge, ensuring system stability and efficiency. This configuration not only boosts the gear ratio but also maintains a compact structure, improving power density and efficiency. Leveraging the magnetic field modulation and differential transmission, a finite element model of this gear is developed and its electromagnetic performance is analyzed.

The torque density of the new radial differential field-modulated two-stage magnetic gear has increased by 44.97% compared to the traditional tandem two-stage magnetic gear. It achieves a high transmission ratio of 64 and maintains comparable power density, indicating strong torque transfer capabilities suitable for low-speed, high-torque applications. During steady-state operation, the torque pulsation difference between the two stages is minimal, ensuring stable working torque.

This research not only propels the forefront of magnetic gear technology through heightened efficiency and streamlined design but also bears profound societal significance in fostering sustainable energy paradigms. By facilitating superior energy conversion efficiencies in wind turbines and wave energy converters, it plays a pivotal role in mitigating carbon emissions and accelerating the global pivot towards cleaner, renewable energy landscapes.

A magnetic gear transmission device is proposed, which can achieve high power density and large transmission ratio at the same time, and this study provides a useful reference for the design optimization of new high-performance multistage magnetic gears.

This paper examines how board structure influences real earnings management and the interaction effect of CEO narcissism on board structure-real earnings management relationship.

The authors used panel data derived from secondary sources from publicly listed firms in Kenya during 2002–2017. Hierarchical regression analysis was used to test the hypotheses.

The results indicate that board independence, board tenure and size have significant negative effect on real earnings management, while CEO duality positively affects real earnings management. Further, the interaction results show that CEO narcissism moderates the relationship between CEO duality and real earnings management.

The results suggest that real earnings management reduces when boards are independent, large and comprising of long-tenured members. However, when the CEO plays dual role of a chairman, real earnings management increases. The authors also find that when CEOs are narcissists, the monitoring role of the board is compromised.

The study adds value to the understanding of how board structure and CEO narcissism influence the monitoring role of the board among firms listed at Nairobi Securities Exchange.