In this paper a novel method is proposed for construction of an exponential observer for nonlinear system. The presented method is based on direct solution of dynamic error without any linearzing of nonlinear terms. Necessary and sufficient conditions for construction of direct observer are presented. Stability of the observer is checked using Lyapunov theorem. Also the ability of this observer...

background: los angeles classification is widely adopted as a means of unifying endoscopic observation for gerd. we assessed the inter- and intra-observer variability of la classification. materials and methods: two-hundred fifty-four still images of the lower esophagus taken by an expert endoscopist (rm) were randomly selected and presented to 9 gastroenterologists (2 females, 6 experts, 3 tra...

The problem of observer design for nonlinear systems has got great attention in the recent literature. The nonlinear observer has been a topic of interest in control theory. In this research, a modified robust sliding-mode observer (SMO) is designed to accurately estimate the state variables of nonlinear systems in the presence of disturbances and model uncertainties. The observer has a simple ...

non-fragile observer design is the main problem of this paper. using continuous frequency distribution, the stability conditions based on integer order lyapunov theorem are derived for lipschitz class of nonlinear fractional order systems. the proposed observer is stable beside the existence of both gain perturbation and input disturbance. for the first time, in this paper a systematic method i...

this paper presents a new observer design methodology for a time varying actuator fault estimation. a new linear matrix inequality (lmi) design algorithm is developed to tackle the limitations (e.g. equality constraint and robustness problems) of the well known so called fast adaptive fault estimation observer (fafe). the fafe is capable of estimating a wide range of time-varying actuator fault...

the problem of observer design for nonlinear systems has got great attention in the recent literature. the nonlinear observer has been a topic of interest in control theory. in this research, a modified robust sliding-mode observer (smo) is designed to accurately estimate the state variables of nonlinear systems in the presence of disturbances and model uncertainties. the observer has a simple ...

In this paper, we propose a new chaos-based communication scheme using the observers. The novelty lies in the masking procedure that is employed to hide the confidential information using the chaotic oscillator. We use a combination of the addition and inclusion methods to mask the information. The performance of two observers, the proportional observer (P-observer) and the proportional integra...

This paper deals with state estimation of micro tunable capacitor subjected to nonlinear electrostatic force. For this end a nonlinear observer has been designed for state estimation of the structure.  Necessary and sufficient conditions for construction of the observer are presented. Stability of the observer is checked using Lyapunov theorem. Observer design is based on converting of differen...

accurate interpretation of radiographic images is dependent on viewing conditions. recently the number of radiology departments has been increased so it needs to use a workstation for reporting. the aim of this study was assess monitor performance and the effect of viewing conditions on object detection. this investigation aimed to quantify the effects of changes in box brightness and ambient l...

The state estimation of a quantized system (Q.S.) is a challenging problem for designing feedback control and model-based fault diagnosis algorithms. The core of a Q.S. is a continuous variable system whose inputs and outputs are represented by their corresponding quantized values. This paper concerns with state estimation of a Q.S. by a qualitative observer. The presented observer in this pape...