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Summary: This paper describes a new robust model predictive control (MPC) scheme to control the discrete‐time linear parameter‐varying input‐output models subject to input and output constraints. Closed‐loop asymptotic stability is guaranteed by including a quadratic terminal cost and an ellipsoidal terminal set, which are solved offline, for the underlying online MPC optimization problem. The main attractive feature of the proposed scheme in comparison with previously published results is that all offline computations are now based on the convex optimization problem, which significantly reduces conservatism and computational complexity. Moreover, the proposed scheme can handle a wider class of linear parameter‐varying input‐output models than those considered by previous schemes without increasing the complexity. For an illustration, the predictive control of a continuously stirred tank reactor is provided with the proposed method. [ABSTRACT FROM AUTHOR]

We discuss robust M-estimation of INARCH models for count time series. These models assume the observation at each point in time to follow a Poisson distribution conditionally on the past, with the conditional mean being a linear function of previous observations. This simple linear structure allows us to transfer M-estimators for autoregressive models to this situation, with some simplifications being possible because the conditional variance given the past equals the conditional mean. We investigate the performance of the resulting generalized M-estimators using simulations. The usefulness of the proposed methods is illustrated by real data examples. [ABSTRACT FROM AUTHOR]

SUMMARY This paper deals with the output stabilization of time-delay systems with sector-bounded nonlinearity and disturbance. In this paper, we will consider the problem of absolute stability for a time-delay systems class, which can be represented as a feedback connection of a linear dynamical system with unknown parameters and an uncertain nonlinearity satisfying a sector constraint. Control algorithm providing exponential stability of equilibrium position without disturbance and L ∞ -stability for disturbed systems is proposed for a class of output. Obtained results are validated with the aid of computer simulation of the two-stage chemical reactor control. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

SUMMARY In this paper, we develop a nonlinear controller to achieve output tracking for a nonminimum phase vertical take-off and landing aircraft without velocity measurements. To attenuate the effects of input disturbances and unmatched uncertainties, auxiliary control inputs are introduced in the state observer. Then by taking the aircraft lateral movement into consideration, a control law is proposed to force the vertical take-off and landing aircraft to asymptotically track the desired trajectories even in the presence of unexpected changes of the trajectories, while driving the unstable internal dynamics to follow the bounded and causal ideal internal dynamics via the stable system center method. Numerical simulation results illustrate the effectiveness and robustness of the proposed controller. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: Mutual inhibitory positive feedback (MIPF), or double-negative feedback, is a key regulatory motif of cellular memory with the capability of maintaining switched states for transient stimuli. Such MIPFs are found in various biological systems where they are interlinked in many cases despite a single MIPF can still realize such a memory effect. An intriguing question then arises about the advantage of interlinking MIPFs instead of exploiting an isolated single MIPF to realize the memory effect. We have investigated the advantages of interlinked MIPF systems through mathematical modeling and computer simulations. Our results revealed that interlinking MIPFs expands the parameter range of achieving the memory effect, or the memory region, thereby making the system more robust to parameter perturbations. Moreover, the minimal duration and amplitude of an external stimulus required for off-to-on state transition are increased and, as a result, external noises can more effectively be filtered out. Hence, interlinked MIPF systems can realize more robust cellular memories with respect to both parameter perturbations and external noises. Our study suggests that interlinked MIPF systems might be an evolutionary consequence acquired for a more reliable memory effect by enhancing robustness against noisy cellular environments. [Copyright &y& Elsevier]