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The purpose of this paper is to present the development of a Matlab/Simulink‐based simulation environment for the design and testing of indirect and direct adaptive flight control laws with fault tolerant capabilities to deal with the occurrence of actuator and sensor failures.

The simulation environment features a modular architecture and a detailed graphical user interface for simulation scenario set‐up. Indirect adaptive flight control laws are implemented based on an optimal control design and frequency domain‐based online parameter estimation. Direct adaptive flight control laws consist of non‐linear dynamic inversion performed at a reference nominal flight condition augmented with artificial neural networks (NNs) to compensate for inversion errors and abnormal flight conditions following the occurrence of actuator or sensor failures. Failure detection, identification, and accommodation schemes relying on neural estimators are developed and implemented.

The simulation environment provides a valuable platform for the evaluation and validation of fault‐tolerant flight control laws.

The modularity of the simulation package allows rapid reconfiguration of control laws, aircraft model, and detection schemes. This flexibility allows the investigation of various design issues such as: the selection of control laws architecture (including the type of the neural augmentation), the tuning of NN parameters, the selection of parameter identification techniques, the effects of anti‐control saturation techniques, the selection and the tuning of the control allocation scheme, as well as the selection and tuning of the failure detection and identification schemes.

The novelty of this research efforts resides in the development and the integration of a comprehensive simulation environment allowing a very detailed validation of a number of control laws for the purpose of verifying the performance of actuator and sensor failure detection, identification, and accommodation schemes.

The purpose of the paper is to present an approach to detect and isolate the aircraft sensor and control surface/actuator failures affecting the mean of the Kalman filter innovation sequence.

The extended Kalman filter (EKF) is developed for nonlinear flight dynamic estimation of an F‐16 fighter and the effects of the sensor and control surface/actuator failures in the innovation sequence of the designed EKF are investigated. A robust Kalman filter (RKF) is very useful to isolate the control surface/actuator failures and sensor failures. The technique for control surface detection and identification is applied to an unstable multi‐input multi‐output model of a nonlinear AFTI/F‐16 fighter. The fighter is stabilized by means of a linear quadratic optimal controller. The control gain brings all the eigenvalues that are outside the unit circle, inside the unit circle. It also keeps the mechanical limits on the deflections of control surfaces. The fighter has nine state variables and six control inputs.

In the simulations, the longitudinal and lateral dynamics of an F‐16 aircraft dynamic model are considered, and the sensor and control surface/actuator failures are detected and isolated.

A real‐time detection of sensor and control surface/actuator failures affecting the mean of the innovation process applied to the linearized F‐16 fighter flight dynamic is examined and an effective approach to isolate the sensor and control surface/actuator failures is proposed. The nonlinear F‐16 model is linearized. Failures affecting the covariance of the innovation sequence is not considered in the paper.

An approach has been proposed to detect and isolate the aircraft sensor and control surface/actuator failures occurred in the aircraft control system. An extended Kalman filter has been developed for the nonlinear flight dynamic estimation of an F‐16 fighter. Failures in the sensors and control surfaces/actuators affect the characteristics of the innovation sequence of the EKF. The failures that affect the mean of the innovation sequence have been considered. When the EKF is used, the decision statistics changes regardless the fault is in the sensors or in the control surfaces/actuators, while a RKF is used, it is easy to distinguish the sensor and control surface/actuator faults.

Customer participation (CP) in service recovery is one of the ways to co-create value with the service provider. Most existing studies assume that customers are willing to participate in service recovery, provided the firm offers them the opportunity. In this study, the authors propose the construct named customer intention to participate in service recovery (CIPSR), develop a scale for it and argue that it is not always implicit but rather is dependent on the consumer's perceived control.

A multi-method approach was used with a combination of qualitative interviews, literature review, unaided dimension identification, correspondence analysis, exploratory factor analysis (EFA), confirmatory factor analysis (CFA) and structural equation modelling to develop the CIPSR scale. The authors used structural equation modelling to test the proposed effect of perceived control on CIPSR.

The study proposes a four-dimensional scale for CIPSR. The authors also found support for the effect of perceived control on CIPSR, with anxiety and failure controllability attribution as intermediate variables.

This study develops a comprehensive scale to measure CIPSR using a rigorous multi-method technique, as well as establishes its importance in the existing literature.

A novel fault-tolerant control (FTC) method is proposed to assure the stability of the remote-operated vehicle (ROV) by considering the thruster failure-induced model perturbations. The stability of the ROV with failures is guaranteed and optimized with the determined model perturbation set. The effectiveness of the double-boundary interval fault-tolerant control (DBIFTC) is verified through the experiments and proves that the stability is well maintained, which demonstrates a decent performance.

This paper studies a control problem for a multi-vector propulsion ROV by using the DBIFTC method in the presence of thruster failure and external disturbances. The ROV kinematics and dynamical models with multi-vector-arranged thruster failure are investigated and formulated for control system design.

In this paper, the authors address the FTC problem of ROV with multi-vector thrusters and propose a DBIFTC scheme. The advantage is that as the kinematic system model of ROV is preanalyzed and identified, the DBIFTC becomes more effective. The mathematical stability of the system under the proposed control scheme can be guaranteed.

The ROV model used in this paper is based on the system identification of experimental data. Although this model has real experimental value and physical significance, the accuracy can be further improved.

Cable-controlled underwater ROVs are widely used in military missions and scientific research because of their flexibility, sufficient load capacity and real-time information transmission characteristics. The DBIFTC method proposed in this paper can effectively reduce the problem of underwater vehicle under propeller failure or external disturbance and save unnecessary cost.

The DBIFTC method proposed in this paper can ensure the attitude stability of ROV or other underwater equipment operating in the event of propeller failure or external disturbance. In this way, the robot can better perform undersea work and tasks.

The kinematics and failure mechanisms of the ROV with multi-vector propulsion system are investigated and established. An optimized DBIFTC scheme is investigated to stabilize ROV yaw attitude under the thruster failure condition. The feasibility and effectiveness of the DBIFTC is experimentally validated.

This study tests a research model for promoting understanding of the responsibility attribution process.

A between-subjects experiment was conducted to test the hypotheses.

The results reveal that counterfactual thinking about how a system failure could have been prevented moderates the effect of cause of misstatement on perceived control. Counterfactual thinking about how an audit failure could have been avoided also moderates the effect of perceived control on causal account. Additionally, causal account mediates the effect of perceived control on responsibility judgment of an audit firm. Inclusion of audit firm size and auditor systems competency as control variables in the hypothesis tests and as grouping variables in the invariance tests does not alter the model results.

Research can guide the audit profession on development of innovative strategies for detecting fraud to protect the interests of decision-makers. Strategies can also be devised to prompt users to consider relevant factors to enhance their ability to arrive at an accurate assessment of an audit firm’s responsibility for an audit failure.

Regulators may need to address whether availability of advanced data analytic tools increases the audit firms’ responsibility for presenting convincing evidence suggesting due diligence in the audit work in the event of an audit failure.

This study examines the process variables influencing responsibility judgment of an audit firm. Elicitation of counterfactual thoughts before the participants responded to the questions measuring the process and dependent variables facilitates discernment of the intensity of counterfactual thinking on the variables examined in the research model.

Discusses the implementation of failure mode and effects analysis (FMEA) for both product design and process control. FMEA is implemented in two ways to ensure that the reliability requirements are met for the production of an airbag inflator. Design FMEA is performed to generate a process control plan, visual aids, and a process verification list. Design FMEA and process FMEA are integrated through reliability prediction and supplier PPM reports. The supplier PPM reports contain the information that can be employed to update the probabilities used in design FMEA. The results of reliability predictions are fed back to eliminate the design weakness. Demonstrates the integrated procedure of the FMEA approach and discusses the relationships among useful tools.

DOWTY ROTOL has recent experience in the design, manufacture and testing of two different electronically controlled wing trailing edge flap high lift actuation systems — one for the British Aerospace B.Ae.146 aircraft and the other for the Construcciones Aeronatuicas/Nurtania CN.235 aircraft. This paper discusses the application of electronics to control and monitor these systems. The resulting equipment is described and the two systems are compared for complexity, type of electronic architecture and reliability.

The research work presented in this paper deals with the design of a reconfigurable flight control system (RFCS) based on the control distribution concept (CDC). The work presented here is concerned with the reconfiguration in response to single and multiple control surface failures. A model of a generic fighter aircraft possessing a relatively large number of control surfaces was selected as a test model for the reconfiguration algorithm. The failure in the form of a control surface stuck at a non‐neutral position is one of the most performances degrading and challenging to recover from by a process of reconfiguration. An algorithm was developed to reconfigure the overall FCS by way of redistributing the control effort to the remaining healthy control surfaces, while at the same time cancelling the effects of control surface deflection locked at a non‐neutral position by the generation of another compensating signal feeding to the FCS.

The purpose of this paper is to present the research into fault detection and isolation (FDI) and evaluation of the reduction of performance after failures occurred in the flight control system (FCS) during its mission operation.

The FDI is accomplished via using the multiple models scheme which is developed based on the Extend Kalman Filter (EKF) algorithm. Towards this objective, the healthy mode of the FCS under different type of failures, including the control surfaces and structural, should be considered. It developed a bank of extended multiple models adaptive estimation (EMMAE) to detect and isolate the above mentioned failures in the FCS. In addition, the performances including the flight envelope, the voyage and endurance in cruising are proposed to reference and evaluate the process of mission, especially for UAV under failure conditions.

The contribution of this paper is to provide the information not only about the failures, but also considering whether the UAV can accomplish the task for the ground station.

The main contribution of this paper is in the areas of the structural and control surface faults researching, which are occurred in the mission procedures and emphasized the identification of those failures' magnitudes. The FDI scheme includes the performance evaluation, while the evaluation obtained through the extensive numerical simulations and saved in the offline database. As a consequence, it is more accurate and less computationally demanding while evaluating the performance.