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The purpose of this study is to develop an active controller of both leading-edge (LE) and trailing-edge (TE) control surfaces for an unmanned air vehicle (UAV) with a composite morphing wing.

Instead of conventional hinged control surfaces, both LE and TE seamless control surfaces were integrated with the wing. Based on the longitudinal state space equation, the root locus plot of the morphing wing aircraft, with a stability augmented system, was constructed. Using the pole placement, the feedback gain matrix for an active control was obtained.

The aerodynamic benefits of a morphing wing section are compared with a wing of a rigid control surface. However, the 3D morphing wing with a large sweptback angle produces a washout negative aeroelastic effect, which causes a significant reduction of the control effectiveness. The results show that the stability augmentation system can significantly improve the longitudinal controllability of an aircraft with a morphing wing.

This study is necessary to analyse the effect of a morphing wing on an UAV and perform a comparison with the rigid model.

The control surfaces assignment plan for trim, pitch and roll control was obtained. An active control algorism for the morphing wing was created to satisfy the required stability and control effectiveness by operating the LE and TE control surfaces according to flight conditions. The aeroelastic effect of control derivatives on the morphing aircraft was considered.

The purpose of the present study is to investigate the community’s view of power outages and their effect on sustainable community development. This research has three aims. This project will first investigate how a blackout affects a community’s ability to live sustainably.

A survey questionnaire was developed that included 22 factors from the literature. The questionnaire was distributed to diversified segments of society from different regions of Pakistan and examined critical factors affecting sustainable community development. A total of 349 (77%) responses were received.

The study results confirm that power failure negatively affects the sustainable life of a community. This study found that the reduced production of large manufacturing, decrease leisure and comfort, reduced public administrative efficiency, loss of educational opportunities and increased use of traditional energy sources are the most important factors for sustainable community development. Findings also suggest that policymakers and practitioners in public organizations need to ensure that projects are completed in a timely manner to meet growing community needs.

The purpose of this research is to address knowledge gaps related to power outages and sustainable community development. The major impact of power disruptions on communities was previously disregarded in development discourse. Participants in these discussions recognize communities as genuine stakeholders and acknowledge that power outages can have a substantial impact on their economic and social development. However, previous studies have neglected to address this phenomenon.

Social ties may either help chief executive officers (CEOs) supervise chief financial officers' (CFOs) behaviors effectively and improve financial reporting quality or lead to collusion and undermine financial reporting quality. Therefore, this paper examines the impact of social ties between CEOs and CFOs on financial reporting quality.

This paper constructs the CEO–CFO social ties through their mutual alma mater or birthplace. Based on 6,787 Chinese non-financial firm-year observations from 2003 to 2020, the paper conducts an empirical test using the multiple regression method.

The main finding is that firms with CEO–CFO social ties are more likely to exhibit higher financial reporting quality. CEOs with social ties to CFOs can obtain a high level of information and exert a better supervisory and monitoring role. Further, CEO–CFO social ties are more effective when the CEO does not have a financial background and when the institutional environment is weak.

This paper mainly contributes to the literature exploring the impact of executive characteristics on financial reporting quality and the literature examining the relation between social ties and corporate behaviors. Meanwhile, the paper emphasizes the important role of social ties as an informal monitoring mechanism in practice.

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.