Search results for "Inequality"

Anterior teeth root inclination prediction derived from digital models: A comparative study of plaster study casts and CBCT images

2018

Background To assess the accuracy of digital models generated using commercially available software to predict anterior teeth root inclination characteristics and compare the results to relevant data obtained from CBCT images. Material and Methods Following sample size calculation and after application of inclusion and exclusion criteria, pre-treatment maxillary and mandibular plaster models and the corresponding CBCT scans of 31 patients attending a private orthodontic clinic were selected. The subjects were 10 males and 21 females with age range 12 to 40 years. Plaster models were scanned using the high resolution mode of an Ortho Insight 3D scanner and CBCT scans were taken using a Kodak…

Static output-feedback control under information structure constraints

2013

An important challenge in the static output-feedback control context is to provide an isolated gain matrix possessing a zero-nonzero structure, mainly in problems presenting information structure constraints. Although some previous works have contributed some relevant results to this issue, a fully satisfactory solution has not yet been achieved up to now. In this note, by using a Linear Matrix Inequality approach and based on previous results given in the literature, we present an e cient methodology which permits to obtain an isolated static output-feedback gain matrix having, simultaneously, a zero-nonzero structure imposed a priori. Peer Reviewed

Static output-feedback controller design for vehicle suspensions: an effective two-step computational approach

2014

In this study, a novel two-step methodology is applied in designing static output-feedback controllers for a class of vehicle suspension systems. Following this approach, an effective synthesis of static output-feedback controllers can be carried out by solving two consecutive linear matrix inequality optimisation problems. To illustrate the main features of the proposed design strategy, two different static output-feedback H 8 controllers are designed for a quarter-car suspension system. The first of those controllers uses the suspension deflection and the sprung mass velocity as feedback information, whereas the second one only requires the sprung mass velocity to compute the control acti…

Static output-feedback control for vehicle suspensions: a single-step linear matrix inequality approach

2013

In this paper, a new strategy to design static output-feedback controllers for a class of vehicle suspension systems is presented. A theoretical background on recent advances in output-feedback control is first provided, which makes possible an effective synthesis of static output-feedback controllers by solving a single linear matrix inequality optimization problem. Next, a simplified model of a quarter-car suspension system is proposed, taking the ride comfort, suspension stroke, road holding ability, and control effort as the main performance criteria in the vehicle suspension design. The new approach is then used to design a static output-feedbackH∞controller that only uses the suspensi…

An Output Feedback Control Design for $$ {\rm H}_\infty $$ Synchronization of Master-Slave Markovian Jump Systems with Time-Varying Delays

2012

In this chapter, an output feedback control proach is proposed for exponential synchronization problem of master slave systems with both discrete and distributed time-varying delays and Markovian switching parameters. Using an appropriate Lyapunov Krasovskii functional, some delay-dependent sufficient conditions and a synchronization law which include the master slave parameters are established for designing a mode-dependent output feedback control law in terms of linear matrix inequalities. The controller guarantees the \( {\rm{H}}_\infty \) synchronization of the two coupled master and slave systems regardless of their initial states. A numerical example is given to show the effectiveness…

2014

This paper is concerned with the problem of general output feedback stabilization for fractional order linear time-invariant (FO-LTI) systems with the fractional commensurate order0<α<2. The objective is to design suitable output feedback controllers that guarantee the stability of the resulting closed-loop systems. Based on the slack variable method and our previous stability criteria, some new results in the form of linear matrix inequality (LMI) are developed to the static and dynamic output feedback controllers synthesis for the FO-LTI system with0<α<1. Furthermore, the results are extended to stabilize the FO-LTI systems with1≤α<2. Finally, robust output feedback control…

The school careers of immigrant's children in France: success and disillusions

2006

06056; This paper will describe the school careers of immigrant children and analyze the patterns of educational inequality in France. It will provide an analysis of immigrant's educational expectations viewed in relation with their children's school careers, taking into account the impact of social, ethnic and geographical origin. In this perspective, we use a rich longitudinal dataset (Ministry of Education 1995 Panel). We point out higher educational expectations among immigrant parents, as compared with native parents of similar social background. High expectations and consistent efforts turn out to be important elements of educational achievement. However some discrepancy appears betwe…

An algorithmic construction of entropies in higher-order nonlinear PDEs

2006

A new approach to the construction of entropies and entropy productions for a large class of nonlinear evolutionary PDEs of even order in one space dimension is presented. The task of proving entropy dissipation is reformulated as a decision problem for polynomial systems. The method is successfully applied to the porous medium equation, the thin film equation and the quantum drift–diffusion model. In all cases, an infinite number of entropy functionals together with the associated entropy productions is derived. Our technique can be extended to higher-order entropies, containing derivatives of the solution, and to several space dimensions. Furthermore, logarithmic Sobolev inequalities can …

Solutions of elliptic equations with a level surface parallel to the boundary: stability of the radial configuration

2016

A positive solution of a homogeneous Dirichlet boundary value problem or initial-value problems for certain elliptic or parabolic equations must be radially symmetric and monotone in the radial direction if just one of its level surfaces is parallel to the boundary of the domain. Here, for the elliptic case, we prove the stability counterpart of that result. We show that if the solution is almost constant on a surface at a fixed distance from the boundary, then the domain is almost radially symmetric, in the sense that is contained in and contains two concentric balls $${B_{{r_e}}}$$ and $${B_{{r_i}}}$$ , with the difference r e -r i (linearly) controlled by a suitable norm of the deviation…

Transportation-cost inequality on path spaces with uniform distance

2008

Abstract Let M be a complete Riemannian manifold and μ the distribution of the diffusion process generated by 1 2 ( Δ + Z ) where Z is a C 1 -vector field. When Ric − ∇ Z is bounded below and Z has, for instance, linear growth, the transportation-cost inequality with respect to the uniform distance is established for μ on the path space over M . A simple example is given to show the optimality of the condition.