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Glass material is largely used for load-bearing components in buildings. For this reason, standardized calculation methods can be used in support of safe structural design in common loading and boundary conditions. Differing from earlier literature efforts, the present study elaborates on the load-bearing capacity, failure time and fire endurance of ordinary glass elements under fire exposure and sustained mechanical loads, with evidence of major trends in terms of loading condition and cross-sectional layout. Traditional verification approaches for glass in cold conditions (i.e. stress peak check) and fire endurance of load-bearing members (i.e. deflection and deflection rate limits) are assessed based on parametric numerical simulations.

The mechanical performance of structural glass elements in fire still represents an open challenge for design and vulnerability assessment. Often, special fire-resisting glass solutions are used for limited practical applications only, and ordinary soda-lime silica glass prevails in design applications for load-bearing members. Moreover, conventional recommendations and testing protocols in use for load-bearing members composed of traditional constructional materials are not already addressed for glass members. This paper elaborates on the fire endurance and failure detection methods for structural glass beams that are subjected to standard ISO time–temperature for fire exposure and in-plane bending mechanical loads. Fire endurance assessment methods are discussed with the support of Finite Element (FE) numerical analyses.

Based on extended parametric FE analyses, multiple loading, geometrical and thermo-mechanical configurations are taken into account for the analysis of simple glass elements under in-plane bending setup and fire exposure. The comparative results show that – in most of cases – thermal effects due to fire exposure have major effects on the actual load-bearing capacity of these members. Moreover, the conventional stress peak verification approach needs specific elaborations, compared to traditional calculations carried out in cold conditions.

The presented numerical results confirm that the fire endurance analysis of ordinary structural glass elements is a rather complex issue, due to combination of multiple aspects and influencing parameters. Besides, FE simulations can provide useful support for a local and global analysis of major degradation and damage phenomena, and thus support the definition of simple and realistic verification procedures for fire exposed glass members.

For a thermal protection system (TPS) of long endurance hypersonic flight vehicle (HFV), its thermal insulation property not only determines by the manufactured morphology but also changes along time. A thermal conductivity prediction model for aerogel considering heat treatment effect is carried out and applied to solve the heat conduction problem of a TPS. The aim of this study is to provide theoretical and numerical references for further development of aerogels applying to TPSs.

A thermal conductivity prediction model for aerogel is established considering treatment effect. The heat conduction problem of a TPS is derived and solved by combining the differential quadrature method and the Runge–Kutta method. The prediction results of aerogel thermal conductivities are verified by comparing with those in literature, while the calculated temperature field of TPS is verified by comparing with that by ABAQUS.

Numerical results show that when applying the current prediction model, the calculated high temperature area in the aerogel layer is narrowed due to the decrease of the thermal conductivity during heat treatment process.

This study will be beneficial to carry out the precise design of TPS for long endurance HFVs.

The purpose of this study is to examine the effects of four different sport programs on various social and subjective health outcomes among prisoners.

Four different sport programs (endurance, strength, dance-like martial arts, soccer) were provided in 2020 and 2021 in a German prison. Participants completed paper-pencil surveys before and after the sport programs (n = 134 observations), including questions about potential social health (enjoyment of physical activity, interpersonal exchange, interpersonal trust, self-efficacy) and subjective health outcomes (health status, health satisfaction, well-being). Further information such as prisoner characteristics were added to the data.

Results of regression analyses show that the endurance program had a significant positive effect on interpersonal trust, while the soccer program had a negative effect. Subjective well-being increased significantly after the strength and the soccer program. The weekly sport hours before imprisonment had a positive association with enjoyment of physical activity and interpersonal exchange while being negatively related to health status and health satisfaction. Furthermore, the number of months of imprisonment before the survey, being a young offender, the prisoners’ body mass index, educational level and migration background were significantly associated with several social and subjective health outcomes.

This study analyzed the effects of different sport programs for prisoners on various social and subjective health outcomes, revealing differences across programs and outcomes. The findings suggest that sport can be a way to enhance prisoners’ social and subjective health, ultimately facilitating their rehabilitation process.

A switching depth controller based on a variable buoyancy system (VBS) is proposed to improve the performance of small autonomous underwater vehicles (AUVs). First, the requirements of VBS for small AUVs are analyzed. Second, a modular VBS with high extensibility and easy integration is proposed based on the concepts of generality and interchangeability. Subsequently, a depth-switching controller is proposed based on the modular VBS, which combines the best features of the linear active disturbance rejection controller and the nonlinear active disturbance rejection controller.

The controller design and endurance of tiny AUVs are challenging because of their low environmental adaptation, limited energy resources and nonlinear dynamics. Traditional and single linear controllers cannot solve these problems efficiently. Although the VBS can improve the endurance of AUVs, the current VBS is not extensible for small AUVs in terms of the differences in individuals and operating environments.

The switching controller’s performance was examined using simulation with water flow and external disturbances, and the controller’s performance was compared in pool experiments. The results show that switching controllers have greater effectiveness, disturbance rejection capability and robustness even in the face of various disturbances.

A high degree of standardization and integration of VBS significantly enhances the performance of small AUVs. This will help expand the market for small AUV applications.

This solution improves the extensibility of the VBS, making it easier to integrate into different models of small AUVs. The device enhances the endurance and maneuverability of the small AUVs by adjusting buoyancy and center of gravity for low-power hovering and pitch angle control.

High Altitude Long Endurance Unmanned Aerial Vehicle (HALE UAV) driven by a hybrid power between battery and solar panel have attracted many researchers. The HALE UAV which develops at Bandung Institute of Technology has design requirements of a 63 kg MTOW with a cruise velocity of 22.1 m/s at an altitude of 60,000 ft propelled by two propellers. The main problems that arise with the propellers gained from the market are these propellers cannot operate properly at the cruise phase due to inadequate thrust and high drag value. This paper aims to design a propeller that solves those problems.

The Larrabee method is used to design this propeller geometry with an output in the form of a chord and twist distribution. The CFD approach method is used to improve the design resulting from the Larrabee method.

This study shows that the inputted thrust value of the propeller designed using the Larrabee method is always higher than the thrust value resulting from the CFD simulation with a difference of around 20% so a design improvement process using CFD is required.

The analysis of propeller implementation in various mission profiles shows that this propeller can operate fully from climbing at sea level to cruising flight at an altitude of 60,000 ft. The same procedure can be applied in other HALE UAV cases to generate a propeller design with different objectives.

During the 1990s, Italian healthcare organisations (HOs) underwent a process of corporatisation, and the most innovative HOs introduced the balanced scorecard (BSC) to address the need for broader accountability. Currently, there is a limited understanding of the dynamics and outcomes of such a process. Therefore, this study aims to explore whether the BSC is still considered an effective performance management tool and analyse the factors driving and hindering its evolution and endurance in public and non-profit HOs.

We conducted a retrospective longitudinal analysis of two pioneering cases in the adoption of the BSC: one in a public hospital and the other in a non-profit hospital. Data collection relied on accessing institutional documents and reports from the early 2000s to the present, as well as conducting semi-structured interviews with the internal sponsors of the BSC.

We found evidence of three main categories of factors that trigger or hinder the adoption and development of the BSC: (1) the role of the internal sponsor and professionals’ commitment; (2) information technology and the controller’s technological skills; and (3) the relationship between the management and professionalism logics during the implementation process. At the same time, there is no evidence to suggest that specific technical features of the BSC influence its endurance.

The paper contributes to the debate on the key factors for implementing and sustaining multidimensional control systems in professional organisations. It emphasises the importance of knowledge-based assets and distinctive internal capabilities for the success of the business. The implications of the BSC legacy are discussed, along with future developments of multidimensional control tools aimed at supporting strategy execution.

This study aims to offer a comprehensive exploration of the potential and challenges associated with sensor fusion-based virtual reality (VR) applications in the context of enhanced physical training. The main objective is to identify key advancements in sensor fusion technology, evaluate its application in VR systems and understand its impact on physical training.

The research initiates by providing context to the physical training environment in today’s technology-driven world, followed by an in-depth overview of VR. This overview includes a concise discussion on the advancements in sensor fusion technology and its application in VR systems for physical training. A systematic review of literature then follows, examining VR’s application in various facets of physical training: from exercise, skill development and technique enhancement to injury prevention, rehabilitation and psychological preparation.

Sensor fusion-based VR presents tangible advantages in the sphere of physical training, offering immersive experiences that could redefine traditional training methodologies. While the advantages are evident in domains such as exercise optimization, skill acquisition and mental preparation, challenges persist. The current research suggests there is a need for further studies to address these limitations to fully harness VR’s potential in physical training.

The integration of sensor fusion technology with VR in the domain of physical training remains a rapidly evolving field. Highlighting the advancements and challenges, this review makes a significant contribution by addressing gaps in knowledge and offering directions for future research.

This study aims to examine the role of royal family members’ board of directors, as a specific aspect of corporate governance, on the firm’s environmental, social and governance (ESG) disclosures. Many firms in the world enjoy special political connections, benefit from tax exemptions and favorable treatments that are largely responsible for their economic endurance and strong performance.

The authors collect data from Thomson Reuters database on Gulf Cooperation Council (GCC)-listed firms for 2010–2018. Royal family board directors’ data is manually collected using a systematic approach to ensure accuracy. Fixed effects’ panel regression model is used to estimate relationships. The authors interact variables to test the moderating effect of board independence and sustainability committee on the influence of royal family board directors.

This study finds that royal family directors on GCC boards negotiate fewer ESG reporting in firms. While board independence, board gender diversity, sustainability committee and governance committee increase the level of ESG-disclosures in the traditional way of reducing agency costs to stakeholders, this study finds that royal family board members convey beneficial consequences on firms without perceiving the need to disclose their ESG activities. Additionally, these firms do not show a spillover effect from the royal family members on the board’s independence or the existence of a sustainability committee; rather these members use a different channel for protecting and building the business value. These results are robust with respect to controls for company size, leverage, return on assets and growth. Instrumental variables are then introduced in the analysis to perform a sensitivity test.

The study results indicate the need to improve GCC market transparency over supplementary limitations that exist on their corporate governance condition. This may be consequential to regulators, lenders and investors. The results suggest the need to raise awareness of the importance of governance and balancing firms’ financial and social performance in the presence of royal family board directors. Policymakers and governance agencies are responsible for promoting the importance of forming sustainability committees and having a set of performance indicators that measure the effectiveness of their actions.

First developed in the 1980s, one of the most essential ideas in international business research has the been the concept of emerging markets. Since the start of the twenty-first century, empirical research has shown that there is no clear correlation between long-term real growth in gross domestic product and real equity returns in firms active in emerging markets. The purpose of this paper is to develop an explanation for both the pervasiveness and endurance of the emerging market discourse despite empirical evidence that substantially questions its very robustness.

The author offers a “weak form” critique of the emerging market discourse that identifies weaknesses and gaps in the emerging market concept and offers suggestions on how to modify it without fundamentally rejecting its conceptual and ideological core. This paper also offers a “strong form” critique of emerging markets as a discourse arguing that the discourse itself is actually propagated to maintain and reinforce global economic inequality and should, therefore, be fundamentally transformed.

Based on the strong form critique of emerging markets discourse, this paper shows how a three-phase process allows emerging market discourse to engender strategic and public policy practice. Scholars and educators play a pivotal role through their writing and discursive interactions with students and executives in their classroom. The centrality of scholars and educators is supported by the broader media ecosystem as well as being reinforced by interactions between executives and policymakers.

This paper makes the case that international business scholars and educators should play a leading role in fundamentally transforming the emerging market discourse and to launch a renewed critical, inter-subjective discussion of dependency and global inequality through three mechanisms: peer-review research; course syllabi and programs; and public intellectualism.

Through critical discourse analysis, this paper addresses for the first time how emerging markets as a concept has prospered in academic and managerial circles despite credible empirical evidence of its lack of robustness.

Dual-thrust hybrid unmanned aerial vehicle (UAV) technology offers a highly robust and efficient system that incorporates the take-off and landing capabilities of rotary-wing aircraft with the endurance capacities of fixed-wing aircraft. The purpose of this study is to model and control a hybrid UAV in three distinct flight modes: rotary-wing, fixed-wing and over-actuated model.

Model predictive control (MPC) along with linear models are applied to design controllers for the rotary-wing or vertical take-off and transition to the fixed-wing flight. The MPC algorithm is implemented with two approaches, first in its usual form and then in a new form with the help of tracking error variables as state variables.

Because the tracking error variables are more compatible with the cost function used in MPC, the results improve significantly. This is especially important for a safe and stable transition from rotary-wing to fixed-wing flight, which should be done quickly. The authors also propose a control allocation strategy with MPC algorithm to exploit the thrust and control inputs of both rotary-wing and fixed-wing systems for the transition phase. As the control system is over-actuated, the proposed algorithm distributes the control signal among the actuators better than the MPC alone. The numerical results show that the flight trajectory is also improved.

The research background is reviewed in the introduction section. The other sections are originally developed in this paper to the best of the authors’ knowledge.