Deposition of La1−x Sr x Fe1−y Co y O3−δ Coatings with Different Phase Compositions and Microstructures by Low-Pressure Plasma Spraying-Thin Film (LPPS-TF) Processes

Perovskite-type materials with the general chemical formula A(1-x) A' (x) B1-y B' (y) O3-delta have received considerable attention as candidates for oxygen separation membranes. Preparation of La1-x Sr (x) Fe1-y Co (y) O3-delta (LSFC) coatings by low-pressure plasma spraying-thin film processes using different plasma spray parameters is reported and discussed. Deposition with Ar-He plasma leads to formation of coatings containing a mixture of cubic LSFC perovskite, SrLaFeO4, FeCo, and metal oxides. Coatings deposited at higher oxygen partial pressures by pumping oxygen into the vacuum chamber contain more than 85% perovskite and only a few percent Fe3-x Co (x) O-4, and/or CoO. The microstructures of the investigated LSFC coatings depend sensitively on the oxygen partial pressure, the substrate temperature, the plasma jet velocities, and the deposition rate. Coatings deposited with Ar-rich plasma, relatively low net torch power, and with higher plasma jet velocities are most promising for applications as oxygen permeation membranes

Adaptive exponential-reaching sliding-mode control for antilock braking systems

[[abstract]]Most commercial antilock braking system (ABS) is based on a look-up table. The table is calibrated through laboratory experiments and engineering field tests under specified road conditions, but it is not adaptive. To attack this problem, this paper proposes an adaptive exponential-reaching sliding-mode control (AERSMC) system for an ABS. The proposed AERSMC system is composed of an equivalent controller and an exponential compensator. The equivalent controller uses a functional-linked wavelet neural network (FWNN) to online approximate the system uncertainties and the exponential compensator is designed to eliminate the effect of the approximation error introduced by the FWNN uncertain observer with an exponential-reaching law. In addition, the adaptive laws online-tune the controller parameters in the sense of Lyapunov function to guarantee the system stability. Finally, the simulation results verify that the proposed AERSMC system can achieve favorable slip tracking performance and is robust against parameter variations in the plant.[[notice]]補正完畢[[incitationindex]]SCI[[booktype]]紙本[[booktype]]電子