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The purpose of this paper is to study the control strategy of transition mode of the stopped-rotor (SR) aircraft under the condition of redundant control and complex aerodynamic characteristics.

This paper first proposes a transition strategy for the conversion between helicopter mode and fixed-wing mode. Then, aiming at the redundancy of the two control systems in the transition process, a control model is proposed, which greatly simplifies the control in conversion mode. Then, to facilitate the design of the control system, the Takagi-Sugeno model of the SR aircraft in transition mode is established. Finally, an explicit model tracking and tuning parameter stability augmentation control system is designed, so that the SR aircraft has a good stability during the transition process. Then, the outer loop control system of transition flight is designed.

The simulation results show that the control strategy proposed in this paper can realize the mode conversion well. It lays a solid foundation for the subsequent engineering flight test for the SR aircraft.

The work done in this paper provides ideas and methods for the flight control system design of SR aircraft in transition mode. The method of designing control model to solve the coordination of redundant control system is also applicable for other multimode aircraft, which provides a simple and convenient method for the multimode aircraft control.

The flexible mode transitions, multiple power sources and system uncertainty lead to challenges for mode transition control of four-wheel-drive hybrid powertrain. Therefore, the purpose of this paper is to improve dynamic performance and fuel economy in mode transition process for four-wheel-drive hybrid electric vehicles (HEVs), overcoming the influence of system uncertainty.

First, operation modes and transitions are analyzed and then dynamic models during mode transition process are established. Second, a robust mode transition controller based on radial basis function neural network (RBFNN) is proposed. RBFNN is designed as an uncertainty estimator to approximate lumped model uncertainty due to modeling error. Based on this estimator, a sliding mode controller (SMC) is proposed in clutch slipping phase to achieve clutch speed synchronization, despite disturbance of engine torque error, engine resistant torque and clutch torque. Finally, simulations are carried out on MATLAB/Cruise co-platform.

Compared with routine control and SMC, the proposed robust controller can achieve better performance in clutch slipping time, engine torque error, vehicle jerk and slipping work either in nominal system or perturbed system.

The mode transition control of four-wheel-drive HEVs is investigated, and a robust controller based on RBFNN estimation is proposed. Compared results show that the proposed controller can improve dynamic performance and fuel economy effectively in spite of the existence of uncertainty.

This paper aims to provide a mathematical modeling and design of H-infinity controller for an autonomous vertical take-off and landing (VTOL) Quad Tiltrotor hybrid unmanned aerial vehicles (UAVs). The variation in the aerodynamics and model dynamics of these aerial vehicles due to its tilting rotors are the key issues and challenges, which attracts the attention of many researchers. They carry parametric uncertainties (such as non-linear friction force, backlash, etc.), which drives the designed controller based on the nominal model to instability or performance degradation. The controller needs to take these factors into consideration and still give good stability and performance. Hence, a robust H-infinity controller is proposed that can handle these uncertainties.

A unique VTOL Quad Tiltrotor hybrid UAV, which operates in three flight modes, is mathematically modeled using Newton–Euler equations of motion. The contribution of the model is its ability to combine high-speed level flight, VTOL and transition between these two phases. The transition involves the tilting of the proprotors from 90° to 0° and vice-versa in 15° intervals. A robust H-infinity control strategy is proposed, evaluated and analyzed through simulation to control the flight dynamics for different modes of operation.

The main contribution of this research is the mathematical modeling of three flight modes (vertical takeoff–forward, transition–cruise-back, transition-vertical landing) of operation by controlling the revolutions per minute and tilt angles, which are independent of each other. An autonomous flight control system using a robust H-infinity controller to stabilize the mode of transition is designed for the Quad Tiltrotor UAV in the presence of uncertainties, noise and disturbances using MATLAB/SIMULINK. This paper focused on improving the disturbance rejection properties of the proposed UAV by designing a robust H-infinity controller for position and orientation trajectory regulation in the presence of uncertainty. The simulation results show that the Tiltrotor achieves transition successfully with disturbances, noise and uncertainties being present.

A novel VTOL Quad Tiltrotor UAV mathematical model is developed with a special tilting rotor mechanism, which combines both aircraft and helicopter flight modes with the transition taking place in between phases using robust H-infinity controller for attitude, altitude and trajectory regulation in the presence of uncertainty.

Drawing from a life course theory, this paper aims to investigate the relationship between material reliance and quality of life for consumers going through a life transition, with attention given to individual differences and transition-specific characteristics.

Study 1 uses qualitative interviews with transitioning consumers, while Study 2 tests a survey-based conditional mediation model.

For liminal consumers, perceived personal control mediates the effect of material reliance on quality of life, but having negative expectations of the transition can override this effect.

Although previous research has given attention to material reliance, personal control and quality of life in various combinations, the impact of their combined effect has not been examined. Furthermore, these constructs have not been examined within the context of life transitions.

This study aims to explore why certain firms can transition successfully to more sophisticated accounting and management control systems than others.

This study uses 20 semi-structured interviews with senior executives of former and present SMEs in the construction industry and business advisory firms to explore the factors behind making sophisticated control systems a permanent organizational feature.

Sophisticated control systems function based on the compliance of lower-level employees, whose lack of buy-in is a major hurdle for smaller firms. Foundational controls of basic human resources and systematic communication routines facilitate their buy-in through accountability, participation and information-sharing, without which firms fail to transition successfully to sophisticated control systems.

The results are based on firms in a single industry and subject to the limitations of cross-sectional research. The transition strategy to more sophisticated control systems is important. This study suggests that foundational controls are necessary to successfully transition to more sophisticated controls.

This study focuses on smaller firms seeking to transition to more sophisticated control systems. This study identifies the key roadblock of noncompliance by lower-level employees, elaborates the role of foundational controls and describes the underlying mechanism behind gaining employee buy-in.

This paper aims to design a global controller that is operational throughout all flight modes and less dependent on an accurate model.

By adopting the interconnection and damping assignment passivity-based control (IDA-PBC) technology and compensating extra inputs for handling the unknown dynamics and time-varying disturbances, a model-free control (MFC)-based global controller is proposed.

Test results indicate that the designed controllers are more suitable for actual flight as they have smaller position tracking errors and energy consumption in all flight phases than the excellent model-free controller intelligent-PID.

The designed global controller, which works in all flight modes without adjusting its structure and parameters, can realize a stable and accurate tracking control of a tail-sitter and improve the resistance to unknown disturbances and model uncertainties.

The newly-designed controller is considered as an enhanced version of the traditional MFC. It further improves the control effect by using the poorly known dynamics of the system and choosing the IDA-PBC as the control auxiliary input. This method eliminates the unnecessary dynamics to continuously stabilize the vehicle with suitable energy consumption covering its entire flight envelope.

This paper aims to examine the internal logical relationship between two intergenerational inheritance ways of passing property rights and residual control rights (RCR) and to construct a conceptual model comprising transfer elements, paths and timing of succession in this process.

Driven by the cases of Haixin, Tianyijiao and Changhe Group, this paper applies research methods of copying and expanding analysis logic, progressive deduction, content analysis and comparative research based on the perspective of HeXie theory to explore the deep interrelation of transfer elements, paths and timing during family business succession.

The findings present that the content of intergenerational inheritance of a family firm is the inheritance of property rights and RCR. First, the inheritance of property rights is a static inheritance of time-point delivery, whereas the inheritance of RCR is a dynamic inheritance process for a period of time. Second, the inheritance of property rights and RCR are not independent; only a “HeXie” succession of both rights can realize a successful inheritance of family firms.

This paper constructs the paths and timing model of intergenerational inheritance of property rights and RCR in family firms. This paper integrates the current literature studies on the family inheritance of property rights and RCR and explains their internal mechanisms. This paper also provides a theoretical foundation and empirical evidence for family business transitions in the business world.

This study aims to understand New Zealand sheep farmers’ readiness toward sustainability transition by assessing their intentions of transition and adoption of sustainability tools, with information collection considered to mediate the intention–adoption relationship.

Based on the data collected from a survey of New Zealand sheep farmers in 2021, the empirical analysis was developed to investigate farmers’ perceptions of and attitudes toward readiness to move toward a sustainability transition. Structural equation modeling associated with principal component analysis was used to empirically test the theory of planned behavior constructs.

The results show that pressure from the public and the sheep industry, and the perceived controls of transition drive the intention of sustainability transition; farmers with higher intention of sustainability transition are found to be more likely to adopt sustainability tools. However, there is an attitude–behavior gap, wherein positive attitudes toward sustainability transition may not lead to a higher likelihood of adopting sustainability tools. There is no evidence of the mediating role of information collection on the intention–adoption relationship, while a positive effect was found in information collection on the adoption of sustainability tools.

The empirical evidence indicates that policymakers need to help increase the awareness of sustainable production and help farmers overcome barriers to achieving sustainable production by finding ways to turn intentions into adoption.

Being the first attempt to empirically assess farmers’ readiness toward sustainability transition, the study fills the gap of limited understanding of the link between sustainability transition intention and sustainable tools adoption in sustainability transition.

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.

The purpose of this paper is to study the internationalization of family firms, exploring specifically if the transition from family control to non-family control (losing family managerial influence) affects a firm’s export activity.

Based on panel data for Spanish firms from 2006 to 2012, a random effect tobit and probit regression and a propensity score matching were run on a sample of 225 firms moving from family to non-family control (switchers) matched with 4,213 firms remaining under family control (non-switchers).

Although from a static viewpoint family controlled firms export less than their non-family counterparts, from a dynamic perspective family firms remaining under family control (non-switchers) are associated with a fall in export activity in comparison with family firms transitioning to non-family control (switchers). Both findings are related back to the socioemotional wealth (SEW) perspective.

The findings of this study shed light on the trade-offs that family firms experience in order to balance their desire to increase their internationalization (and the risk associated with it) and their wish to maintain SEW.

The findings should encourage family owners and managers to take long-term strategic decisions leading to internationalization which, although risky, will prevent subsequent loss of SEW in terms of family control.

This work provides evidence concerning family firms’ willingness to undertake risky activities, such as internationalization, considering the threats to their wealth.