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The purpose of this paper is to improve autonomous flight performance of a fixed-wing unmanned aerial vehicle (UAV) via simultaneous morphing wingtip and control system design conducted with optimization, computational fluid dynamics (CFD) and machine learning approaches.

The main wing of the UAV is redesigned with morphing wingtips capable of dihedral angle alteration by means of folding. Aircraft dynamic model is derived as equations depending only on wingtip dihedral angle via Nonlinear Least Squares regression machine learning algorithm. Data for the regression analyses are obtained by numerical (i.e. CFD) and analytical approaches. Simultaneous perturbation stochastic approximation (SPSA) is incorporated into the design process to determine the optimal wingtip dihedral angle and proportional-integral-derivative (PID) coefficients of the control system that maximizes autonomous flight performance. The performance is defined in terms of trajectory tracking quality parameters of rise time, settling time and overshoot. Obtained optimal design parameters are applied in flight simulations to test both longitudinal and lateral reference trajectory tracking.

Longitudinal and lateral autonomous flight performances of the UAV are improved by redesigning the main wing with morphing wingtips and simultaneous estimation of PID coefficients and wingtip dihedral angle with SPSA optimization.

This paper originally discusses the simultaneous design of innovative morphing wingtip and UAV flight control system for autonomous flight performance improvement. The proposed simultaneous design idea is conducted with the SPSA optimization and a machine learning algorithm as a novel approach.

Integrating person-job fit theory with the stressor-emotion model of counterproductive work behavior (CWB), the current study aims to examine which behavioral pattern (fight: CWB vs flight: withdrawal) employees are more likely to adopt when they experience perceived overqualification (POQ). We further investigate anger as the underlying emotional mechanism for these relations because anger can be expressed and thus reflected in CWB, or constrained and thus reflected in withdrawal behavior. Furthermore, different stressor-attenuating strategies including relaxation during work breaks and mastery experiences at work are examined as mitigating factors of these relations.

Time-lagged data were collected from 176 full-time employees in China using a field survey research design.

We found that employees who experience POQ are more likely to engage in withdrawal than in CWB. Anger mediated the relations of POQ with both CWB and withdrawal. Relaxation moderated the relation between POQ and anger, as well as the indirect relations of POQ with CWB and withdrawal through anger.

This study enhances understanding of employees’ affective and behavioral reactions to POQ. However, the survey design was not longitudinal and causality cannot be established.

POQ is associated with undesirable employee behaviors and should therefore be avoided by organizations. If POQ is unavoidable, organizations can use job design and offer training to foster relaxation in between tasks among employees.

In the framework of person-job fit theory, our study provides insight about employees’ “fight” or “flight” responses to POQ, and further illustrates the mechanism and the attenuating factors in this processes.

In March 2020, the Australian Government restricted the entry of travelers into Australia by closing its international borders in an effort to contain the spread of the coronavirus (COVID-19). While Australian citizens who were resident overseas could return to Australia under certain conditions, the border closures significantly affected their ability to return to Australia and as a consequence had a dramatic impact on their lives and the lives of their families. This chapter explores the effects of the Australian government’s decision to close the national border by presenting the lived experiences of Australian citizens adversely affected by the government’s decision. The research is based on an online survey conducted in late 2021 and early 2022. Based on the findings, this chapter explores notions of Australian citizenship rights and privileges in the context of the pandemic, and the profound impacts the national lockout had on Australians as individuals, family members and on their sense of national identity. A central finding of this research reveals how citizens’ separation from family during the lockout placed considerable stress on the family as a social institution and caused significant impacts on Australians’ physical and mental health.

This study aims to investigate the potential impact and passenger perceptions of integrating multimedia books within airline services, aiming to elucidate the evolving landscape of in-flight entertainment and reading experiences.

A quantitative research methodology was used, using a structured questionnaire distributed to presenters at the International Federation of Library Associations.

Analysis revealed varying passenger interest in multimedia books, with approximately 57.7% displaying engagement, while 40.4% demonstrated limited interest or none. However, a notable majority (60.6%) preferred multimedia books over traditional print books during flights. Furthermore, 90.4% perceived a positive impact of multimedia books on flight reading experiences, leading to increased satisfaction (81.7%) and a high likelihood of recommending airlines offering such content (91.3%).

The study's limitations include a specific focus on International Federation of Library Associations and Institutions (IFLA) World Library and Information Congress (WLIC) presenters, potentially limiting broader generalisations. Further research might explore the preferences of a wider demographic range and incorporate qualitative aspects to deepen understanding. Airlines could leverage multimedia books to enhance passenger satisfaction, attract diverse audiences and foster cultural inclusivity within in-flight entertainment.

This study contributes insights into the evolving landscape of in-flight entertainment, emphasising the significant potential and positive impact of integrating multimedia books within airline services. It underscores the importance of catering to diverse passenger preferences and enhancing overall satisfaction during air travel.

This study aims to provide an empirical investigation into rising capital flight and the role of institutional quality to mitigate its effect on the real sector in sub-Saharan Africa (SSA).

The study uses the system generalized method of moments and uses data spanning from 1989 to 2020 from 26 SSA countries.

The findings show that capital flight has no direct impact on the real sector while institutional quality adversely impacted the agricultural and industrial sectors. The study also found that institutional quality is unable to mitigate the effect of capital flight on the industrial sector.

This study investigates if institutional quality mitigates the impact of capital flight on the real sector proxied by industrial value-added and agriculture value-added.

The paper aims to investigate the relationship between institutions and economic growth in developing countries, considering the role of financial inclusion, education spending and military spending.

The study employs dynamic panel analysis, specifically two-step system generalized method of moments (GMM), on a sample of 61 developing countries over the period 2009–2020.

The results confirm that weak institutional quality, weak financial inclusion and increased military spending are barriers to economic growth, conversely, increased spending on education and gross capital formation contribute to economic growth in developing countries. Regarding the specific institutional factor, we find that corruption, ineffective government, voice and accountability and weak rule of law contribute negatively to growth.

The study calls for strengthening institutions so that the financial system supports economic growth and suggests increasing spending on education to improve access to and the quality of human capital, which is an important determinant of economic growth.

The study contributes to scarce literature by empirically analyzing the relationship between institutions and economic growth by considering the role of financial inclusion, public spending on education and military spending, factors that have been ignored in previous studies. In addition, the study identifies the institutional dimension that contributes to reduced economic growth in developing countries.

The authors examine whether or not applicants and recipients of federal disability insurance (DI) inflate their self-assessed health (SAH) problems relative to others. To do this, the authors employ a technique which uses anchoring vignettes. This approach allows them to examine how various cohorts of the population interpret survey questions associated with subjective self-assessments of health. The results of the analysis suggest that DI participants do inflate the severity of a given health problem, but by a small but significant degree. This tendency to exaggerate the severity of disability problems is much more apparent among those with more education (especially those with a college degree). In contrast, racial minorities tend to underestimate severity ratings for a given disability vignette when compared to their white peers.

This study aims to develop a measurement scale for employee aesthetic labor (AL) in hospitality from the perspectives of frontline employees of international tourist hotels and airlines.

The authors utilized both qualitative and quantitative methods to develop the AL scale. Participants were frontline employees of international tourist hotels and airlines in Taiwan. The authors’ analysis incorporated both exploratory and confirmatory factor analyses to examine the results.

A four-factor, 21-item hospitality AL scale with satisfactory validity and reliability was created. The four AL factors are appropriate voice and response, pleasant appearance, corporate aesthetic image delivery and polite and elegant demeanor.

The developed AL scale can serve as a useful tool for the hospitality industry in terms of employee recruitment and training to align with the corporation's aesthetic image and reduce the potential burden of AL on employees.

Based on dramaturgical theory, this study focuses on the AL practices that are performed during service encounters with customers. It is potentially the first AL scale to be constructed using rigorous scale development procedures.