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Argues that in increasingly turbulent and complex environments, the tools of “systems thinking” may provide a valuable resource in the drive to attain integration between strategic and operational objectives. Particular examples in the domain of production control and supply‐chain management are presented as illustrations of the dynamicist’s paradigm. Hence it is suggested that familiar concepts such as JIT/Kanban and supply chains are actually special cases of generic feedback control principles, while pure MRP is a classic example of feedforward. In practice, the complexities of real world operations require combinations of these two approaches and the paper therefore assesses the implications of these theoretical concepts, for the design of practical operations systems.

To provide an approach to vibration reduction of flexible spacecraft which operates in the presence of various disturbances, model uncertainty and control input non‐linearities during attitude control for spacecraft designers, which can help them analyze and design the attitude control system.

The new approach integrates the technique of active vibration suppression and the method of variable structure control. The design process is twofold: first design of the active vibration controller by using piezoelectric materials to add damping to the structures in certain critical modes in the inner feedback loop, and then a second feedback loop designed using the variable structure output feedback control (VSOFC) to slew the spacecraft and satisfy the pointing requirements.

Numerical simulations for the flexible spacecraft show that the precise attitude control and vibration suppression can be accomplished using the derived vibration attenuator and attitude control controller.

Studies on how to control the flywheel (motor) under the action of the friction are left for future work.

An effective method is proposed for the spacecraft engineers planning to design attitude control system for actively suppressing the vibration and at the same time quickly and precisely responding to the attitude control command.

This paper fulfills a useful source of theoretical analysis for the attitude control system design and offers practical help for the spacecraft designers.

This paper aims to propose an improved direct torque control (DTC) for the induction motor’s performance enhancement using dual nonlinear techniques. The exact feedback linearization is implemented to create a linear decoupled control. Besides, the fuzzy logic control approach has been inserted to generate the auxiliary control input for the feedback linearization controller.

To improve the DTC for induction motor drive, this work suggests the incorporation of two nonlinear approaches. As the classical feedback linearization suffers while the presence of uncertainties and modeling inaccuracy, it is recommended to be associated to another robust control approach to compensate the uncertainties of the model and make a robust control versus the variations of the machine parameters. Therefore, fuzzy logic controllers will be integrated as auxiliary inputs to the feedback linearization control law.

The simulation and the experimental validation of the proposed control algorithm show that the association of dual techniques can effectively achieve high dynamic behavior and improve the robustness against parameters variation and external disturbances. Moreover, the space vector modulation is used to preserve a fixed switching frequency, reduce ripples and low switching losses.

The theoretical, simulation and experimental studies prove that the proposed control algorithm can be used on different AC machines for variable speed drive applications such as oil drilling, traction systems and wind energy conversion systems.

The proposed DTC strategy has been developed theoretically and realized through simulation and experimental implementation. Different operation conditions have been conducted to check the ability and robustness of the control strategy, such as steady state, speed reversal maneuver, low-speed operation and parameters variation test with load application.

While the use of computerized decision aids in accounting is widespread, little is known about the effects of decision aids on accounting decision making. However, prior research has often noted the difficulty in getting users to accept and rely upon decision aids (Rose, 2002). A primary area of focus in the design of decision aids that will facilitate user acceptance and reliance has been the development of user-centered interfaces that increase the user's comfort with the aid. This study contributes to this body of research by extending the findings of Ryan, Mims, and Koestner (1983) on the use of informational versus controlling rewards to the context of a decision aid and the interface design. While Ryan et al. focused on the effects of verbal feedback on intrinsic motivation, this study focuses on the impact of text-based feedback from a decision aid on decision performance for a choice task. Additionally, this study examines the effect of task-contingent versus performance-contingent rewards on the impact of the decision aid feedback. The results indicate a differential effect from that of Ryan et al. (1983) when feedback is provided through a decision aid and the focus is on decision performance rather than the precursor condition of intrinsic motivation. Additional research is needed to help explain why the findings obtained by Ryan et al. do not hold in the context of computerized decision aid use when decision performance is measured directly. There are important implications of these findings both in terms of theory development and decision aid design in professional decision-making environments such as accounting.

The examination of contextual factors that enhance or stifle employees’ creative performance is a new but rapidly growing research area. Theory and research in this area have focused on antecedents of employee creativity. In this paper, we review and discuss the major theoretical frameworks that have served as conceptual foundations for empirical studies. We then provide a review and critical appraisal of these empirical studies. Based on this review, we propose exciting possibilities for future research directions. Finally, we discuss implications of this body of work for human resource management.

This paper aims to propose output feedback-based control algorithms for the flight control system of a scaled, un-crewed helicopter in its hover flight mode.

The proposed control schemes are based on H_∞ control and composite nonlinear control. The gains of the output feedback controllers are obtained as the solution of a set of linear matrix inequalities (LMIs).

In the proposed schemes, the finite-time convergence of system states to trim condition is achieved with minimum deviation from the steady-state. As the proposed composite nonlinear output feedback design improves the transient response, it is well suited for a scaled helicopter flight. The use of measured output vector instead of the state vector or its estimate for feedback provides a simple control structure and eliminates the need for an observer in real-time application. The proposed control strategies are relevant to situations in which a simple controller is essential due to economic factors, reliability and hardware implementation constraints.

The proposed control strategies are relevant to situations in which a simple controller is essential due to economic factors, reliability and hardware implementation constraints. They also have significance in applications where the number of measurement quantities needs to be minimized such as in a fully functional rotor-craft unmanned aerial vehicle.

The developed output feedback control algorithms can be used in small-scale helicopters for numerous civilian and military applications.

This work addresses the LMI-based formulation and solution of an output feedback controller for a hovering un-crewed helicopter. The stability and robustness of the closed-loop system are proved mathematically and the performance of the proposed schemes is compared with an existing strategy via simulation studies.

The purpose of this paper is to report a study investigating the predictors of acceptance of multisource feedback (MSF) by managers. Specifically, it investigates the extent to which locus of control, cynicism and perceptions of procedural justice predicted acceptance by feedback recipients.

Quantitative data were analysed from 520 questionnaires completed by managers who participated in a multisource feedback programme as part of a leadership development process.

The study findings reveal that managers' perception of procedural justice was most significant in explaining variance in acceptance of MSF. Cynicism also explained significant variance in acceptance.

The findings highlight the importance of attending to procedural justice issues when implementing MSF. They also highlight the need to assess cynicism levels in the organisation.

The study combines variables not included in previous studies.

Presents, from a systemic perspective, an examination and discussion of performance measurement, performance indicators and associated improvement initiatives, as typically applied in public sector organisations. Such mechanisms are usually implemented as a causal loop which is established between perceived performance and resulting actions, thereby constituting a form of feedback control. Within this context a two‐dimensional matrix model is postulated in which the independent dimensions are the source of control and the nature of the resultant control‐action. The paper examines the implications revealed by this model within the context of performance management and system dynamics. The potential role of influence diagrams and dynamic simulation models is thereby introduced as a potential means of unravelling the complex behaviour which can often arise in the presence of such interactive cause‐effect loops. A number of typical examples, drawn from within the public sector, are invoked to illustrate the discussion.

This paper aims to use the Matsuoka’s neural oscillators as the basic units of central pattern generator (CPG), and to offer a new CPG architecture consisting of a dual neural CPG of circular three links responsible for oscillator phase adjustment, to which an external neural oscillator is added, which is responsible for oscillator amplitude adjustment, to control foot depth to balance itself when treading on an obstacle.

It is equipped with a triaxial accelerometer and a triaxial gyroscope to obtain a real-time robot attitude, and to disintegrate the foot tilt in each direction as feedback signals to CPG to restore the robot’ horizontal attitude on an uneven terrain. The CPG controller is a distributed control method, with each foot controller consisting of a group of reciprocally coupling neural oscillators and sensors to generate different locomotion by different coupling patterns.

The experiment results indicated that the gait design method succeeded in enabling a steady hexapod walking on a rugged terrain, the mode of response is such that adjustments can only be made when the tilt occurs.

The overall control mechanism uses individual foot tilts as the feedback signal input to the neural oscillators to change the amplitude and compare against the reference oscillators of fixed amplitude to generate the foot height reference signals that can balance the body, and then convert the control signals, through a trajectory generator, to foot trajectories from which the actual rotation angle of servo motors can be obtained through inverse kinematics to achieve the effect of restoring the balance when traveling.

The controller design based on the bionic CPG model has the ability to restore its balance when its body tilts. In addition to the model’s ability to control locomotion, from the response waveforms of this experiment, it can also be noticed that it can control the foot depth to balance itself when treading on an obstacle, and it can adapt to a changing environment. When the obstacle is removed, the robot can quickly regain its balance.

This paper aims to present a shape sensing method and feedback control strategy based on fiber Bragg grating (FBG) sensor to improve the control accuracy of the robot and ensure the safety of the cardiac interventional surgery.

To theoretically describe the shape of the catheter robot, the kinematic model is established by the geometric analysis method. And to obtain the actual shape, a large curvature assemble sensor based on FBG is adopted and a novel simple shape reconstruction model is proposed, which can provide the shape curve and distal position. In addition, the influence of external load on the bending deformation is investigated by experiments. To improve the shape accuracy of the robot, a shape feedback control method is presented to control the catheter robot, which can control the robot to bend into the pre-given desired shape.

Experiment results verify the effectiveness of the shape sensing method and the reconstruction model, and the correlation coefficients of three sets of curve in different coordinate directions are 0.9986, 0.9992 and 0.9999. Results of the shape feedback experiment show that the curvature error and direction angle error are 1.42% and 10.3%, respectively. The continuum catheter robot can be controlled to achieve the desired bending shape.

The shape reconstruction method and feedback control strategy proposed in this paper can improve the control accuracy of the robot to avoid the risk of the collision with the surrounding blood vessels, the tissues and organs.