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The discrete-time uncertain nonlinear models are considered in a Takagi-Sugeno form and their stabilization is studied through a nonquadratic Lyapunov function. The classical conditions consider a onesample variation, here, the main results are obtained considering k samples variation, i.e., [[DELTA].sub.[kappa]] V(x(t)) = V(x(t + k)) - V(x(t)). The results are shown to always include the classical cases, and several examples illustrate the effectiveness of the approach. Index Terms--Linear matrix inequality (LMI), nonlinear discrete models, nonquadratic Lyapunov function, uncertain Takagi-Sugeno fuzzy model.

Interspecies hybrids between distinct species of the genus Xiphophorus are often used in varied research investigations to identify genomic regions associated with the inheritance of complex traits. There are 24 described Xiphophorus species and a greater number of pedigreed strains; thus, the number of potential interspecies hybrid cross combinations is quite large. Previously, select Xiphophorus experimental crosses have been shown to exhibit differing characteristics between parental species and among the hybrid fishes derived from crossing them, such as widely differing susceptibilities to chemical or physical agents. For instance, genomic regions harboring tumor suppressor and oncogenes have been identified via linkage association of these loci with a small set of established genetic markers. The power of this experimental strategy' is related to the number of genetic markers available in the Xiphophorus interspecies cross of interest. Thus, we have undertaken the task of expanding the suite of easily scored markers by characterization of Xiphophorus microsatellite sequences. Using a cross between Xiphophorus maculatus and X. andersi, we report a linkage map predominantly composed of microsatellite markers. All 24 acrocentric chromosome sets of Xiphophorus are represented in the assembled linkage map with an average intergenomic distance of 7.5 cM. Since both male and female [F.sub.1] hybrids were used to produce backcross progeny, these recombination rates were compared between 'male' and 'female' maps. Although several genomic regions exhibit differences in map length, male- and female-derived maps are similar. Thus Xiphophorus, in contrast to zebrafish, Danio rerio, and several other vertebrate species, does not show sex-specific differences in recombination. The microsatellite markers we report can be easily adapted to any Xiphophorus interspecies and some intraspecies crosses, and thus provide a means to directly compare results derived from independent experiments.

Byline: D. Khiar, J. Lauber, T.M. Guerra, T. Floquet, G. Colin, Y. Chamaillard This paper deals with the non-linear modelling and control of a turbocharged spark ignition engine. In the automotive industry, downsizing-based turbocharging is considered as a powerful technique to improve engine performances as fuel economy, pumping loss reduction to increase engine efficiency or driveability optimisation. This method is largely used for diesel engines. For gasoline engines, it is more complex in terms of control. In this work, a simplified control-oriented model is presented and validated using a Smart MCC three cylinders engine data. Then, based on this model, a fuzzy non-linear control law is calculated to achieve the fuel consumption and pumping losses reduction by setting the engine states to a given profile.

This paper deals with the admissibilisation with guaranteedH∞performance of linear parameter-varying (LPV) discrete-time singular systems under gain-scheduled (GS) state-feedback control. In particular, we focus on systems with descriptor matrix of LPV form and unknown/unmeasurable disturbance input. To our best knowledge and despite its practical interest, this problem has not been fully investigated and still poses relevant issues, which motivates our study. By means of a proposed descriptor redundancy approach, in combination with the bounded real lemma and Finsler's Lemma, a method based on linear matrix inequalities is proposed to design a GS state-feedback control with maximumH∞performance. Finally, a numerical example is given to illustrate the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

This paper considers the stabilisation of switching nonlinear models by switching between the subsystems. We assume that arbitrary switching between two subsystems is possible once a subsystem has been active for a predefined number of samples. We use a Takagi–Sugeno representation of the models and a switching Lyapunov function is employed to develop sufficient stability conditions. If the conditions are satisfied, we construct a switching law that stabilises the system. The application of the conditions is illustrated in several examples. [ABSTRACT FROM AUTHOR]

This paper presents a discrete-time control design methodology for input-saturating systems using a Lyapunov function with dependence on present and past states. The approach is used to bypass the usual difficulty with full polynomial Lyapunov functions of expressing the problem in a convex way. Also polynomial controllers are allowed to depend on both present and past states. Furthermore, by considering saturation limits on the control action, the information about the relationship between the present and past states is introduced via Positivstellensatz multipliers. Sum-of-squares techniques and available semi-definite programming (SDP) software are used in order to find the controller. [ABSTRACT FROM PUBLISHER]