District pharmacies in Malawi use a computerised IS to monitor the flow of products from a warehouse to health service delivery points and determine understocked or overstocked products at each health facility. Currently, all drug LMIS reports are in tabular forms. The GIS can help health and drug logistics officers to get additional spatial information, such as locations of health facilities a...

A new approach to robust sampled-data control is introduced. The system is modelled as a continuous-time one, where the control input has a piecewise-continuous delay. Sufficient linear matrix inequalities (LMIs) conditions for sampled-data state-feedback stabilization of such systems are derived via descriptor approach to time-delay systems. The only restriction on the sampling is that the dis...

This paper proposes a Time Delay nonlinear dynamic model of HIV-1 (Human Immunodeficiency Virus type 1), introducing the drug consumption efficiencies as the controlling input for the model. The paper also represents the fuzzy T-S representation and the corresponding Fuzzy T-S controller. The controller parameters are tuned using LMIs (Linear Matrix Inequalities). The main focus is on the stabi...

The problem of stochastic stability is investigated for a class of neural networks with both Markovian jump parameters and continuously distributed delays. The jumping parameters are modeled as a continuous-time, finite-state Markov chain. By constructing appropriate LyapunovKrasovskii functionals, some novel stability conditions are obtained in terms of linear matrix inequalities LMIs . The pr...

This paper examines the problem of designing robust H∞ controllers for for HIV/AIDS infection system with dual drug dosages described by a Takagi-Sugeno (TS) fuzzy model. Based on a linear matrix inequality (LMI) approach, we develop an H∞ controller which guarantees the L2-gain of the mapping from the exogenous input noise to the regulated output to be less than some prescribed value for the s...

Abstract: By using the Lyapunov second method, the robust control and robust optimal control for the gas tungsten arc welding dynamic process whose underlying continuous-time systems are subjected to structured uncertainties are discussed in time-domain. As results, some sufficient conditions of robust stability and the corresponding robust control laws are derived. All these results are design...

This paper deals with the problem of H1 model reduction for linear continuous time-delay systems. For a given delay system, the problem we address is the construction of a reduced-order model such that the associated model error satis® es a prescribed H1 norm bound constraint. Two alternative methods for obtaining reduced-order models are presented. Su cient conditions for the existence of des...

In this paper, the input covariance constraint (ICC) control problem is solved by convex optimization subject to linear matrix inequalities (LMIs) constraints. The ICC control problem is an optimal control problem that is concerned to obtain the best output performance subject to multiple constraints on the input covariance matrices. The contribution of this paper is the characterization of the...

This paper investigates the problem of robust output feedback control for a class of uncertain discrete-time fuzzy systems with time delays. The state–space Takagi–Sugeno fuzzy model with time delays and norm-bounded parameter uncertainties is adopted. The purpose is the design of a full-order fuzzy dynamic output feedback controller which ensures the robust asymptotic stability of the closed-l...

Static output-feedback stabilization for the nth order vector differential equations by using artificial multiple delays is considered. Under assumption of the stabilizability of the system by a static feedback that depends on the output and its derivatives up to the order n − 1, a delayed static output-feedback is found that stabilizes the system. The conditions for the stability analysis of t...