The main part in hydraulic system is directional control valve. Directional control valve has complex construction such as moving spool to control the direction of actuator for required speed. Magneto-rheological (MR) fluid is one of controllable fluids. Utilizing the MR fluid properties, direct interface can be realized between magnetic field and fluid power without the need for moving parts like spool in directional control valves. This study proposes the design of four ways/three position MR proportional directional control valve (4/3 MR valve). The construction of valve and the principle of work are presented. Analysis for magnetic circuit and simulation for valve performance were done. The experiment was conducted to show the principle work of the valve functionally. Design and finite elements analysis using FEMM software of the MR valves were done to reach the optimal design. The valve works proportionally to control the direction and speed of hydraulic actuators. As the result, the optimal design of the valve achieved the optimum performance. The experimental result demonstrates the operation of 4/3 MR valve in 12 configurations. The 4/3 MR valve can replace many types of the spool directional control valve for controlling hydraulic actuator.
Single phase capacitor-run induction motors (IMs) are used in various applications such as home appliances and machine tools; they are affected by the sags or swells and any fault that can lead to disturb the supply and make it produce rms voltage below or above the rated motor voltage, which is 220V. A control system is designed to regulate the output voltage of the converter irrespective to the variation of the load and within a specific range of supply voltage variation. The steady-state equivalent circuit of the Buck-Boost chopper type AC voltage regulator, as well as the analysis of this circuit are presented in this paper. Switching device for the regulator is an IGBT Module. The proposed chopper uses pulse width modulation (PWM) c
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The aim of this work is to create a power control system for wind turbines based on fuzzy logic. Three power control loop was considered including: changing the pitch angle of the blade, changing the length of the blade and turning the nacelle. The stochastic law was given for changes and instant inaccurate assessment of wind conditions changes. Two different algorithms were used for fuzzy inference in the control loop, the Mamdani and Larsen algorithms. These two different algorithms are materialized and developed in this study in Matlab-Fuzzy logic toolbox which has been practically implemented using necessary intelligent control system in electrical engineerin
... Show MoreThe temperature control process of electric heating furnace (EHF) systems is a quite difficult and changeable task owing to non-linearity, time delay, time-varying parameters, and the harsh environment of the furnace. In this paper, a robust temperature control scheme for an EHF system is developed using an adaptive active disturbance rejection control (AADRC) technique with a continuous sliding-mode based component. First, a comprehensive dynamic model is established by using convection laws, in which the EHF systems can be characterized as an uncertain second order system. Second, an adaptive extended state observer (AESO) is utilized to estimate the states of the EHF system and total disturbances, in which the observer gains are updated
... Show MoreAbstract—The upper limb amputation exerts a significant burden on the amputee, limiting their ability to perform everyday activities, and degrading their quality of life. Amputee patients’ quality of life can be improved if they have natural control over their prosthetic hands. Among the biological signals, most commonly used to predict upper limb motor intentions, surface electromyography (sEMG), and axial acceleration sensor signals are essential components of shoulder-level upper limb prosthetic hand control systems. In this work, a pattern recognition system is proposed to create a plan for categorizing high-level upper limb prostheses in seven various types of shoulder girdle motions. Thus, combining seven feature groups, w
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This research presents a on-line cognitive tuning control algorithm for the nonlinear controller of path-tracking for dynamic wheeled mobile robot to stabilize and follow a continuous reference path with minimum tracking pose error. The goal of the proposed structure of a hybrid (Bees-PSO) algorithm is to find and tune the values of the control gains of the nonlinear (neural and back-stepping method) controllers as a simple on-line with fast tuning techniques in order to obtain the best torques actions of the wheels for the cart mobile robot from the proposed two controllers. Simulation results (Matlab Package 2012a) show that the nonlinear neural controller with hybrid Bees-PSO cognitive algorithm is m
... Show MoreYeasts are distributed in all environments and have been reported as potential biocontrol agents against various phytopathogenic fungi. To investigate their enzymatic and biological activities, 32 yeasts were isolated from 15 date vinegar samples. Evaluation of the antagonistic activities of isolated yeasts against the plant pathogens Fusarium oxysporium, Sclerotinia sclerotiorum, and Macrophomina phaseolina indicated that there are two yeasts had the highest inhibitory effect against plant pathogens, these yeasts identified as Kluyveromyces marxianus and Torulaspora delbrueckii using traditional and molecular methods. These yeast isolates were tested for fungal cell wall degrading enzymes (in vitro), and results indicated that the
... Show MoreIn the presence of deep submicron noise, providing reliable and energy‐efficient network on‐chip operation is becoming a challenging objective. In this study, the authors propose a hybrid automatic repeat request (HARQ)‐based coding scheme that simultaneously reduces the crosstalk induced bus delay and provides multi‐bit error protection while achieving high‐energy savings. This is achieved by calculating two‐dimensional parities and duplicating all the bits, which provide single error correction and six errors detection. The error correction reduces the performance degradation caused by retransmissions, which when combined with voltage swing reduction, due to its high error detection, high‐energy savings are achieved. The res
... Show MoreThe current study has beenconduced to evaluate the effect of extracted crude terpens at the concentrations of 6,8% of seeds of Eucalyptuscamaldulensison the 4th larval instar oftheCallosobruchusmaculates and the percentage of the cowpea seed germination.The Results showed that the terpens extract of the concentration of 8% increases the mortality rate of the fourth larval instar and it reach to 63.3%, and then decrease of to 26.6,20% at concentration of 6%and forcontrol treatment respectively The percentage of adult emergence reduces to 0% at the concentration of 8% compared with control treatment in which it reach to 66.6%. The extraction atbothconcentrations 6,8% does not affect the germination rate
Evaluating treatment effect on interferon-alpha in female patients with systemic lupus erythematosus: a case-control study