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This paper investigates the problem of delay-dependent H <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">∞</sub> memory filtering for continuous-time semi-Markovian jump linear systems (MJLSs) with time-varying delay in an input-output framework. Differing from the constant transition rates (TRs) in the conventional MJLSs, the TRs of the semi-MJLSs depend on the random sojourn-time and are thus with time-varying characteristics. By utilizing a two-term approximation for the terms with time-varying delay, it is first shown that the filtering error system (FES) can be reformulated into a feedback interconnection form and the stability and performance analysis problem of the FES can be recast as the scaled small gain (SSG) problem of an interconnected system. Then, based on a semi-Markovian Lyapunov-Krasovskii formulation of SSG condition combined with projection lemma, the H <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">∞</sub> filter synthesis for the underlying semi-MJLSs is formulated in terms of linear matrix inequalities. Finally, simulation studies are provided to evaluate the effectiveness and superiority of the proposed design method.

In this paper, we propose a method of modeling for vehicle crash systems based on viscous and elastic properties of the materials. This paper covers an influence of different arrangement of spring and damper on the models' response. Differences in simulating vehicle - to - rigid barrier collision and vehicle - to - pole collision are explained. Comparison of the models obtained from wideband (unfiltered) acceleration and filtered acceleration is done. At the end we propose a model which is suitable for localized collisions simulation.

This paper is concerned with the stabilization problem for a class of uncertain discrete impulsive switched delay systems under asynchronous switching. The so-called asynchronous switching means that the switches between the candidate controllers and system modes are asynchronous. By using the average dwell time (ADT) approach, sufficient conditions for the existence of an asynchronously switched controller is derived such that the resulting closed-loop system is exponentially stable. The desired controller gains and the admissible switching signals are obtained in terms of a set of matrix inequalities. A numerical example is given to illustrate the effectiveness of the proposed method.

Object Oriented Programming (OOP) is a programming paradigm which be highlighted using the 800xa system. This work will investigate the use of OOP programming for designing industrial application control based on a soft controller. The different types of objects which can be defined in different classes, declaration and implementation using the 800xa will be explored, thus highlighting the use of static, dynamic and embedded objects. In the next phase, an illustration on how to map and use these objects in ABB 800xA for efficient control, hence, providing a systematic approach for accessing any of the plant aspects using a unique plant object.

This paper deals with the problem of mixed H 2 /H ∞ control for an offshore floating wind turbine system. Firstly, we consider the modeling of a wind turbine system with collective pitch control scheme and the interaction with drive train dynamics and tower motions. The scenario is for the above rated wind speed conditions, where the goal is to keep the rotor rotational speed at its rated value while mitigating oscillations in the drive train and tower. Secondly, we present an effective technique to design a dynamic output-feedback mixed H 2 /H ∞ controller with pole placement constraints using a linear matrix inequality (LMI) approach. Pole placement constraints are implemented in order to improve the closed loop system response. Finally, a model obtained from the wind turbine simulation software FAST is used to illustrate the effectiveness of the proposed design technique.

In this paper by applying the Quantized space and time theory, the speed limit of protons has been determined and consequently the Lorentz factor has been calculated with a high degree of accuracy. Eventually the mass equivalent to energy of Higgs boson which is created by collision of two proton beams (This experiment has been performed in LHC) has been calculated precisely to .

In this article, a computational method based on Haar wavelet in time-domain for solving the problem of optimal control of the linear time invariant systems for any finite time interval is proposed. Haar wavelet integral operational matrix and the properties of Kronecker product are utilized to find the approximated optimal trajectory and optimal control law of the linear systems with respect to a quadratic cost function by solving only the linear algebraic equations. It is shown that parameter estimation of linear system can be done easily using the idea proposed. On the basis of Haar function properties, the results of the article, which include the time information, are illustrated in two examples.

The problems of stability analysis and control synthesis for a class of neural systems with time-varying delays and nonlinear uncertainties are addressed. The dynamical system under consideration consists of different time-varying neutral and discrete delays without any restriction on upper bounds of derivatives of both delays. Based on the Lyapunov–Krasovskii functional theory, delay-dependent sufficient linear matrix inequalities (LMIs) conditions are established for the stability and stabilization of the considered system using some free matrices and the Leibniz–Newton formula. Control synthesis is to design a delayed state-feedback scheme based on a convex optimization method such that the resulting closed-loop system is asymptotically stable and satisfies a prescribed level of H ∞ performance. The simulation results illustrate the effectiveness of the proposed methodology.

In this paper, the problem of passivity-based sliding mode control (SMC) for uncertain delayed stochastic systems (DSS) within state-observer framework is under consideration. A novel linear sliding surface is first presented with the aid of the provided observer and output information, and a new sufficient condition on the passivity and mean square exponential stability of the underlying closed-loop system during the sliding mode is then derived by employing the stochastic stability theory and linear matrix inequality approach. Further, an associated SMC law is designed to guarantee the arrival of the sliding surface almost surely via the adaptive methodology. Finally, two illustrative examples concerning the desirable performance of the system are conducted to confirm the effectiveness and superiority of the proposed method.

This paper deals with the robust delay-dependent H <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">⋡</inf> filtering problem for a class of LPV systems with multiple constant time-delays in the state vector. It is shown that, by using the Hamiltonian-Jacoby-Isaac (HJI) function and the polynomially parameter-dependent quadratic functions and a suitable change of variables, the required sufficient conditions with high precision are established in terms of parameter-independent linear matrix inequalities (LMIs) for the existence of the desired H <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">⋡</inf> filters. However, the explicit expression of the robust delay-dependent H <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">⋡</inf> filters is derived to satisfy both asymptotic stability and H <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">⋡</inf> performance. A numerical example is provided to demonstrate the validity of the proposed design approach.

In this paper, a non-fragile fuzzy control design is proposed for a class of nonlinear systems with mixed discrete and distributed time delays. The Takagi and Sugeno (T-S) fuzzy set approach is applied to the modelling of the nonlinear dynamics, and a T-S fuzzy model is constructed, which can represent the nonlinear system. Then, based on the fuzzy linear model, a fuzzy linear controller is developed to stabilize the nonlinear system. The control law is obtained to ensure stochastically exponentially stability in the mean square. The sufficient conditions for the existence of such a control are proposed in terms of certain linear matrix inequalities.

This report considers attempts to develop dummy motorcyclists with breakable legs. Material characteristics are discussed. The variation in the scatter fracture load of different materials is compared using the Weibull modulus. The materials used in the different dummy legs have been calibrated statically and uni-axially whereas in crash tests multi-axial dynamic loads are sustained. The Independent Action criterion is used to show that: (1) compressive and torsion loads have only a small effect on bending; and (2) differences in results from different laboratories is the result of scatter in the material characteristics. The effect that leg fracture has on dummy trajectory is described using previously published experimental pedestrian impacts, motorcycle crash tests and pedestrian and car occupant computer simulation studies. Head trajectory is shown to be largely unaffected by leg fracture. For the covering abstract of the conference see IRRD 864606.

This paper investigates the problems of delay-dependent stability analysis and memory ℋ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">∞</sub> controller synthesis for a class of continuous-time Markovian jump linear systems (MJLSs) via an input-output (IO) approach. The generality lies in that the exactly known, partially unknown and uncertain transition rates are simultaneously incorporated into the defective mode information. It is first shown that the original system with time-varying delay can be reformulated by a new IO model through a process of two-term approximation and the stability problem of the original system can be transformed into the scaled small gain (SSG) problem of the IO model. Then, based on a Markovian Lyapunov-Krasovskii formulation of SSG condition together with some convexification techniques, the stability analysis and state-feedbackℋ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">∞</sub> controller synthesis conditions for the underlying MJLSs are formulated in terms of linear matrix inequalities. Simulation studies are provided to illustrate the effectiveness and superiority of the proposed analysis and design methods.

This paper deals with the controller synthesis for a class of positive two-dimensional (2D) switched delay systems described by the Roesser model. This kind of systems has the property that the states take nonnegative values whenever the initial boundaries are nonnegative, some delay-dependent sufficient conditions for the exponential stability of positive 2D switched systems with state delays are given. Furthermore, the design of positive state feedback controller under which the resulting closed-loop system meets the requirements of positivity and exponential stability is presented in terms of linear matrix inequalities (LMIs). An example is included to illustrate the effectiveness of the proposed approach.

Published post-print of an article in the journal: Proceedings of the Institution of Mechanical Engineers, Part I: Journal of Systems and Control Engineering Available from the publisher at: http://dx.doi.org/10.1243/09596518jsce730