Wyniki wyszukiwania - BazTech

1

Effects of viscoelastic and porous materials on sound transmission of multilayer systems

Felhi H., Trabelsi H., Taktak M., Chaabane M., Haddar M.

Journal of Theoretical and Applied Mechanics

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2018

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Vol. 56 nr 4

961--976

EN

Multilayer structures allow obtaining good performance in acoustic insulation to eliminate unwanted noise in the medium and high frequencies in many applications such as building and transport industry. In this paper, the sound transmission of multilayer systems is studied using the Transfer Matrix Method (TMM). The studied multi-layered panels include elastic, viscoelastic and porous materials. Several configurations of multilayer systems are studied, and their corresponding transmission loss T L is computed. Also, the effects of porous material characteristics are studied to evaluate the impact of each parameter.

2

Robust controlled positive delayed systems with interval parameter uncertainties: A delay uniform decomposition approach

Elloumi W., Mehdi D., Chaabane M.

International Journal of Applied Mathematics and Computer Science

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2018

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Vol. 28, no. 3

441--450

EN

This paper is concerned with robust stabilization of continuous linear positive time-delay systems with parametric uncertainties. The delay considered in this work is a bounded time-varying function. Previously, we have demonstrated that the equidistant delay-decomposition technique is less conservative when it is applied to linear positive time-delay systems. Thus, we use simply a delay bi-decomposition in an appropriate Lyapunov–Krasovskii functional. By using classical and partitioned control gains, the state-feedback controllers developed in our work are formulated in terms of linear matrix inequalities. The efficiency of the proposed robust control laws is illustrated with via an example.

3

A new experimental set-up for the characterisation of magneto-mechanical behaviour of materials submitted to biaxial stresses. Application to FeCo alloys

Hubert O., Chaabane M., Jumel J., Maurel V., Alves F., Bensalah A.D., Besbes M., Azoum K., Daniel L., Bouillault F.

Przegląd Elektrotechniczny

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2005

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R. 81, nr 5

19-23

EN

This paper is dealing with a new experimental set-up built to get magneto-mechanical behaviour of ferromagnetic materials under biaxial stress state. This set-up is using the more recent techniques of measurement. An uniaxial set-up is nevertheless required to get reference magneto-mechanical measurements. First results concerning the magneto-mechanical behaviour of an iron-cobalt alloy submitted to uniaxial stress are presented.

PL

Przedstawiono nowe stanowisko badawcze do określania właściwości magnetomechanicznych materiałów poddanych dwuosiowym obciążeniom. Układ wykorzystuje nowe techniki pomiaru. Jako układ odniesienia użyto układu do badania obciążeń jednoosiowych. Przedstawiono wyniki badań właściwości stopów FeCo.

4

Stability and stabilizability of a class of uncertain dynamical systems with delays

Saadni M. S., Chaabane M., Mehdi D.

International Journal of Applied Mathematics and Computer Science

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2005

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Vol. 15, no 3

321-329

EN

This paper deals with a class of uncertain systems with time-varying delays and norm-bounded uncertainty. The stability and stabilizability of this class of systems are considered. LinearMatrix Inequalities (LMI) delay-dependent sufficient conditions for both stability and stabilizability and their robustness are established.