An analysis of on-line autonomous robust tracking controller based on variable structure control is presented for an aerospace launch vehicle. Decentralized sliding-mode controller is designed to achieve the decoupled asymptotic tracking of guidance commands upon plant uncertainties and external disturbances. Development and application of the controller for an aerospace launch vehicle during a...

In recent years some multi-mode pushover procedures taking into account higher mode effects, have been proposed. The responses of considered modes are combined by the quadratic combination rules, while using the elastic modal combination rules in the inelastic phases is not valid. Here, an optimum weighted mode combination method for nonlinear static analysis is presented. Genetic algorithm is ...

An important consideration in control issues is control of nonlinear systems. Sliding control is among those nonlinear controllers that can control the system desirably in the presence of unstructured uncertainties of carelessness in specifying parameters of the system. In sliding control, also called Variable Structure Control, the main objectives of the controller &#10are achieved by introduc...

An important consideration in control issues is control of nonlinear systems. Sliding control is among those nonlinear controllers that can control the system desirably in the presence of unstructured uncertainties of carelessness in specifying parameters of the system. In sliding control, also called Variable Structure Control, the main objectives of the controller are achieved by introducin...

This paper proposes a novel method based on pulse width modulation techniques toreduce and control the common-mode voltage in three-phase multilevel inverters. Besides controllingthe common-mode voltage, this method is capable of controlling capacitors voltages and load currentswith low switching losses and harmonic contents. In fact, due to the existence of different pulsepatterns and the poss...

This paper discusses the application of the plantwide control design procedure of Skogestad [Skogestad, S. (2004a). Control structure design for complete chemical plants. Computers and Chemical Engineering, 28, 219–234] to the ammonia synthesis process. Threemodes of operation are considered: (I) given feed rate, (IIa) maximum throughput, and (IIb) “optimized” throughput. Two control structures...

results there was no significant differences between if and conventional mode regarding visibility of mic (p > 0.05). conclusion although using if caused improved visibility of mic, the difference with conventional mode was not statistically different. patients and methods in this cross-sectional study, 2580 digital panoramic images of 18 to 70-year-old patients were inspected for presence of m...

A design of a compact, easy to fabricate and applicable structure rectangular waveguide TM11 to TE10 mode converter is presented in this paper. The design procedure of the proposed structure can be divided into two parts in sequence. The beginning one is dedicated to the transformation from TM11 to TEM mode using a central conductor, while the second part is the transformation from TEM to TE10 ...

Evaporation of micro-liter drops from solid surfaces at room condition is mainly governed by diffusion. Therefore, there should be no difference between evaporation rate of sessile and pendant drops. However, some studies indicate a difference and explain the difference using buoyancy. The objective here is to reconcile the inconsistency in the literature. For that, first, by comparing two iden...

The subject of structural health monitoring and damage identification of structures at the earliest possible stage has been a noteworthy topic for researchers in the last years. Modal strain energy (MSE) based index is one of the efficient methods which are commonly used for detecting damage in structures. It is also more effective and economical to employ some methods for reducing the degrees ...