This paper proposes feedback linearization control (FBLC) based on function approximation technique (FAT) to regulate the vibrational motion of a smart thin plate considering the effect of axial stretching. The FBLC includes designing a nonlinear control law for the stabilization of the target dynamic system while the closed-loop dynamics are linear with ensured stability. The objective of the FAT is to estimate the cubic nonlinear restoring force vector using the linear parameterization of weighting and orthogonal basis function matrices. Orthogonal Chebyshev polynomials are used as strong approximators for adaptive schemes. The proposed control architecture is applied to a thin plate with a large deflection that stimulates the axial loading thus, the plate behaving nonlinearly. The governing partial differential equation for the piezo-plate system is transformed into definite ordinary differential equations (ODEs) using the Galerkin approach; hence, multi-input multi-output ODEs are obtained. Simulation experiments are performed to verify the validity of the proposed control structure.
This research is considered one of the important researches in Maysan Governorate, as it focuses on the construction of helicopter airport project in the oil fields of the Maysan Oil Company, where the oil general companies in Maysan Governorate suffer from the cost of transporting the foreign engineering experts and the governing equipment of sustaining oil industry from Iraq's international airports to oil fields and vice versa. Private international transport companies transport foreign engineering from the oil fields to Iraqi airports and vice versa, and other international security companies take action to provide protection for foreign engineering experts during transportation. Hence, this process is very costly.
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... Show MoreBACKGROUND: Transverse fractures of the patella are important fractures with a wide variety of subtypes, the common incidence in the age group of 20–50 years. Surgical interference aims to achieve a perfect alignment of the joint surface, in addition to rigid fixation of the fracture for early re-habitation and early movement to retain the extensor mechanism of the knee joint. AIM: The aim of this study was to compare the radiological and functional outcomes of the displaced transverse patella fracture in adult patients treated by ORIF using tension band wiring versus cannulated screws with wiring. METHODS: A prospective analytic comparative study was conducted in Al-Kindy Teaching Hospital/Baghdad/Iraq for 18 months from Apr
... Show MoreBackground: This in vitro study compares a novel calcium-phosphate etchant paste to conventional 37% phosphoric acid gel for bonding metal and ceramic brackets by evaluating the shear bond strength, remnant adhesive and enamel damage following water storage, acid challenge and fatigue loading. Material and Methods: Metal and ceramic brackets were bonded to 240 extracted human premolars using two enamel conditioning protocols: conventional 37% phosphoric acid (PA) gel (control), and an acidic calcium-phosphate (CaP) paste. The CaP paste was prepared from β-tricalcium phosphate and monocalcium phosphate monohydrate powders mixed with 37% phosphoric acid solution, and the resulting phase was confirmed using FTIR. The bonded premolars were exp
... Show MoreBackground: Radial neck fractures in children account for 5 to 10% of all elbow fractures in children. They are extra-articular fractures of the radius proximal to the bicipital tuberosity. The physis is typically involved as a Salter-Harris I or II pattern. Alternatively, the fracture sometimes is extraphyseal, through the metaphysis. In children there is considerable potential for remodeling after these fractures. Up to 30° of radial head tilt and up to 3 mm of transverse displacement are acceptable. Many modalities of treatment are available regarding Surgical &Non-Surgical treatments. Objectives: To evaluate the functional outcome after surgical percutaneous joystick reduction therapy of severely angulated radial neck fracture i
... Show MoreThis paper provides an identification key to the species of Orthetrum Newman, 1833 (Odonata, Libellulidae), including six species that were collected from different localities in Iraq.
The species of O. anceps (Schneider, 1845) is registered as a new record in Iraq; the most important characters which are used in diagnostic key are included
Numerical investigation has been carried out on heat transfer and friction factor characteristics of copper-water nanofluid flow in a constant heat-fluxed tube with the existence of new configuration of vortex generator using Computational Fluid Dynamics (CFD) simulation. Two types of swirl flow generator: Classical twisted tape (CTT) and Parabolic-cut twisted tape (PCT) with a different twist ratio (= 2.93, 3.91 and 4.89) and different cut depth (= 0.5, 1.0 and 1.5 cm) with 2% and 4% volume concentration
... Show MoreIn this study, the first kind Bessel function was used to solve Kepler equation for an elliptical orbiting satellite. It is a classical method that gives a direct solution for calculation of the eccentric anomaly. It was solved for one period from (M=0-360)° with an eccentricity of (e=0-1) and the number of terms from (N=1-10). Also, the error in the representation of the first kind Bessel function was calculated. The results indicated that for eccentricity of (0.1-0.4) and (N = 1-10), the values of eccentric anomaly gave a good result as compared with the exact solution. Besides, the obtained eccentric anomaly values were unaffected by increasing the number of terms (N = 6-10) for eccentricities (0.8 and 0.9). The Bessel
... Show MoreThe solidification process in a multi-tube latent heat energy system is affected by the natural convection and the arrangement of heat exchanger tubes, which changes the buoyancy effect as well. In the current work, the effect of the arrangement of the tubes in a multi-tube heat exchanger was examined during the solidification process with the focus on the natural convection effects inside the phase change material (PCM). The behavior of the system was numerically analyzed using liquid fraction and energy released, as well as temperature, velocity and streamline profiles for different studied cases. The arrangement of the tubes, considering seven pipes in the symmetrical condition, are assumed at different positions in the system, i
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