6 research outputs found

    Design of an Interval Fuzzy Type-2- PID Controller for a Gas Turbine Power Plant

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    In this paper, an interval fuzzy type-2 PID controllers are designed for speed and Exhaust temperature in a heavy duty Gas Turbine (HDGT) power plant and the model selected is Rowen’s model to present the mechanical behavior of the gas turbine, the work is aimed to improve the system dynamic performance of speed and Exhaust temperature for a 56.6 MW, 50 HZ, simple cycle, single shaft heavy duty gas turbine, all gains for conventional  PID and interval fuzzy type-2 PID are tuned using Social Spider Optimization(SSO) technique, we show the performance improvement for interval fuzzy type -2 PID controller in comparison with conventional PID via simulation

    Design and implementation of an interval Type-2 Fuzzy Logic and type-1 fuzzy logic controls for Magnetic Levitation System

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    The aim of this paper is the synthesis of an interval type-2 fuzzy logic PID and type-1 fuzzy logic controllers for magnetic levitation system to keep a metal ball suspended in mid-air by changing the field strength of an electromagnet coil, Performances of the suggestion controller are estimated and compared that controller with those of type-1 fuzzy logic PID controller by using the same structure and under similar operating conditions. Simulation results showed that the interval type-2 fuzzy logic PID controller has better performances than those of type-1fuzzy logic PID controller. The parameters of PID controller have been modifying through particle swarm optimization (PSO).The simulation of magnetic levitation system based on its Mathematical model is carried out in MATLAB

    Experimental Investigation on the Thermophysical and Rheological Behavior of Aqueous Dual Hybrid Nanofluid in Flat Plate Solar Collectors

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    This work investigates the thermal–physical and rheological properties of hexagonal boron nitride/carbon nanotubes (hBN/CNTs) applied to reinforce water-based working fluid in a flat plate solar collector (FPSC). The hybrid nanoadditives of hBN and the chemically functionalized CNTs (CF-CNTs) were suspended in distilled water (DW) with a nonionic surfactant. The hybridization ratio between CF-CNTs and hBN was optimized to be 40:60. The thermal efficiency tests on the solar collector were carried out using different volumetric flow rates (2, 3, and 4 L/min) under the ASHRAE-93-2010 standard. The morphological characteristics of the hybrid nanoadditives were evaluated using X-ray diffraction (XRD), ultraviolet–visible spectroscopy (UV–vis), field emission scanning electron microscopy (FESEM), and transmission electron microscopy (TEM). Different concentrations of hBN/CF-CNTs were added to the water-based working fluid to record the optimal wt.% for maximum enhancement in the FPSC’s efficiency. The results revealed that using only 0.1 wt.% of hBN/CF-CNTs with a flow rate of 4 L/min remarkably improved the collector efficiency by up to 87% when compared to the conventional working fluid used in FPSC

    Emphysematous Gastritis in the Setting of Chronic Abdominal Pain

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    Emphysematous gastritis is a rare but fatal variant of gastritis. It is caused by gastric wall invasion by gas-forming organisms. It follows disruption of gastric mucosal integrity by a variety of factors, most commonly caustic ingestion and alcohol abuse. Patients typically present with abdominal symptoms with features of septic shock. Emphysematous gastritis carries a high mortality rate warranting early intervention with supportive measures and broad-spectrum antibiotics. It is essential to consider this rare entity in the differential diagnosis of a patient presenting with abdominal pain as timely intervention is crucial for survival

    Adaptive Synergetic Motion Control for Wearable Knee-Assistive System: A Rehabilitation of Disabled Patients

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    In this study, synergetic-based adaptive control design is developed for trajectory tracking control of joint position in knee-rehabilitation system. This system is often utilized for rehabilitation of patients with lower-limb disabilities. However, this knee-assistive system is subject to uncertainties when applied to different persons undertaking exercises. This is due to the different masses and inertias of different persons. In order to cope with these uncertainties, an adaptive scheme has been proposed. In this study, an adaptive synergetic control scheme is established, and control laws are developed to ensure stable knee exoskeleton system subjected to uncertainties in parameters. Based on Lyapunov stability analysis, the developed adaptive synergetic laws are used to estimate the potential uncertainties in the coefficients of the knee-assistive system. These developed control laws guarantee the stability of the knee rehabilitation system controlled by the adaptive synergetic controller. In this study, particle swarm optimization (PSO) algorithm is introduced to tune the design parameters of adaptive and non-adaptive synergetic controllers, in order to optimize their tracking performances by minimizing an error-cost function. Numerical simulations are conducted to show the effectiveness of the proposed synergetic controllers for tracking control of the exoskeleton knee system. The results show that compared to classical synergetic controllers, the adaptive synergetic controller can guarantee the boundedness of the estimated parameters and hence avoid drifting, which in turn ensures the stability of the controlled system in the presence of parameter uncertainties
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