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Proxy-based sliding mode vibration control with an adaptive approximation compensator for euler-bernoulli smart beams
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Proxy-based sliding mode control PSMC is an improved version of PID control that combines the features of PID and sliding mode control SMC with continuously dynamic behaviour. However, the stability of the control architecture maybe not well addressed. Consequently, this work is focused on modification of the original version of the proxy-based sliding mode control PSMC by adding an adaptive approximation compensator AAC term for vibration control of an Euler-Bernoulli beam. The role of the AAC term is to compensate for unmodelled dynamics and make the stability proof more easily. The stability of the proposed control algorithm is systematically proved using Lyapunov theory. Multi-modal equation of motion is derived using the Galerkin method. The state variables of the multi-modal equation are expressed in terms of modal amplitudes that should be regulated via the proposed control system. The proposed control structure is implemented on a simply supported beam with two piezo-patches. The simulation experiments are performed using MATLAB/SIMULINK package. The locations of piezo-transducers are optimally placed on the beam. A detailed comparison study is implemented including three scenarios. Scenario 1 includes disturbing the smart beam while no feedback loop is established (open-loop system). In scenario 2, a PD controller is applied on the vibrating beam. Whereas, scenario 3 includes implementation of the PSMC+AAC. For all previously mentioned scenarios, two types of disturbances are applied separately: 1) an impulse force of 1 N peak and 1 s pulse width, and 2) a sinusoidal disturbance with 0.5 N amplitude and 20 Hz frequency. For impulse disturbance signals, the results show the superiority of the PSMC+AAC in comparison with the conventional PD control. Whereas, both the PSMC+ACC and the PD control work well in the case of a sinusoidal disturbance signal and the superiority of the PSMC is not clear.

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Publication Date
Thu Mar 01 2012
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Predicting changes on budget expenditures using Markov chains with practical application
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The researchers have a special interest in studying  Markov  chains as one of the probability samples which has many applications in different fields. This study comes to deal with the changes issue that happen on budget expenditures by using statistical methods, and Markov chains is the best expression about that as they are regarded reliable  samples in the prediction process. A transitional matrix is built for three expenditure cases (increase ,decrease ,stability) for one of budget expenditure items (base salary) for three directorates (Baghdad ,Nineveh , Diyala) of one  of the ministries. Results are analyzed by applying  Maximum likelihood estimation  and Ordinary least squares  methods resulting

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Publication Date
Mon Mar 25 2024
Journal Name
International Journal Of Drug Delivery Technology
Solubility and Dissolution Enhancement of Candesartan Cilexetil by Complexation with Cyclodextrin
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At present, numerous novel chemical compounds face challenges related to their limited solubility in aqueous environments. These compounds are classified under the Biopharmaceutical Classification System (BCS) as either class II or class IV substances. Different carriers were used to increase their solubility. Candesartan cilexetil (CC) is one of the most widely used antihypertensive drugs, which belongs to class II drugs. The aim of this research was to enhance the solubility and dissolution rate of CC through a complexation approach involving β-cyclodextrin and its derivatives, specifically hydroxypropyl beta cyclodextrin (HP-β-CD), methyl beta cyclodextrin (M-β-CD), and sulfonyl ether beta-cyclodextrin (SBE-β-CD), serving as

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Publication Date
Mon Jan 01 2024
Journal Name
Aip Conference Proceedings
A multivariate Bayesian model using Gibbs sampler with real data application
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In many scientific fields, Bayesian models are commonly used in recent research. This research presents a new Bayesian model for estimating parameters and forecasting using the Gibbs sampler algorithm. Posterior distributions are generated using the inverse gamma distribution and the multivariate normal distribution as prior distributions. The new method was used to investigate and summaries Bayesian statistics' posterior distribution. The theory and derivation of the posterior distribution are explained in detail in this paper. The proposed approach is applied to three simulation datasets of 100, 300, and 500 sample sizes. Also, the procedure was extended to the real dataset called the rock intensity dataset. The actual dataset is collecte

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Publication Date
Wed Nov 01 2023
Journal Name
Iop Conference Series: Earth And Environmental Science
Replacing Formalin with Alcohol and its Effect on Preserved Fish Specimens
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Abstract<p>This study aims to formulate an alternative solution for Formalin for preserving fish as study specimens for long periods. The main reason for finding a solution instead of formalin is to get rid of the negative effects of this solution on those who work with it, as well as to better preserve the bodies of fish. Hence, three new solutions were proposed to replace formalin. Thus, Formalin, in turn, may enter the composition of a small part of these solutions to give better results and for long periods of keeping specimens. All solutions prepared in this study participated in being acidic as in formalin. Two solutions succeeded in compensating for the use of formalin in preserving fish </p> ... Show More
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Publication Date
Wed Oct 31 2018
Journal Name
Al-kindy College Medical Journal
Leigh Syndrome: Report of a Rare Case with Late Onset Presentation
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Leigh's syndrome, or sub acute necrotizing encephalomyelopathy, is a rare inherited neurometabolic disease of infancy and early childhood with variable course and prognosis. Rarely, it occurs in juveniles and adults. The diagnosis is difficult and still remains to challenge the clinicians on the basis of history; hence the role of imaging is very essential. It is the neuroimaging, chiefly the Magnetic Resonance Imaging showing characteristic symmetrical necrotic lesions in the basal ganglia and/or brain stem that leads to the diagnosis. Late-onset varieties are rare and only few cases were reported all over the world. Here, I report a case of late onset (juvenile) Leigh syndrome presenting with an acute polyneuropathy. Neuroimaging confi

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Publication Date
Sun Jun 04 2017
Journal Name
Baghdad Science Journal
Synthesis of Pure Nano semiconductor Oxide ZnO with Different AgNO3 Concentrations
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Zinc oxide nanoparticles sample is prepared by the precipitation method. This method involves using zinc nitrate and urea in aqueous solution, then (AgNO3) Solution with different concentrations is added. The obtained precipitated compound is structurally characterized by X-ray diffraction (XRD), Scanning electron microscopy (SEM), Atomic force microscopy (AFM) and Fourier transform infrared spectroscopy (FTIR). The average particle size of nanoparticles is around 28nm in pure, the average particle size reaches 26nm with adding AgNO3 (0.05g in100ml =0.002 M) (0.1g in100ml=0.0058M), AgNO3 (0.2g in 100ml=0.01M) was 25nm. The FTIR result shows the existence of -CO, -CO2, -OH, and -NO2- groups in sample and oxides (ZnO, Ag2O).and used an

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Publication Date
Thu Feb 01 2024
Journal Name
Iop Conference Series: Earth And Environmental Science
Survey of Insects Associated with some Species of Cucurbitaceae in Iraq
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Abstract<p>Due to the spread of insect pests that destroys the crops belonging to the Cucurbitaceae family and led to deterioration in crop productivity in Iraq due to various reasons, the most important of which is Climate fluctuation and extreme weather events have a major impact on this problem. So, this paper was proposed to identify those species pests and prevalence. Insects were collected during the period from March 1. 2022 to October 30, 2022 from the several regions of Iraq, including: Baghdad, Babylon, Basra, Karbala, Wasit, Diyala, Saladin, and Duhok Provinces. The results showed 19 important species under 17 genera with 13 families, and five orders. The most common synonyms and dist</p> ... Show More
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Publication Date
Wed Sep 02 2020
Journal Name
International Journal Of Pharmaceutical Research
Prevalence of Bacterial Species Associated With Infants Meningitis Patients in Iraq
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Publication Date
Fri Jan 01 2016
Journal Name
Applied Numerical Mathematics
Multiple time-dependent coefficient identification thermal problems with a free boundary
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Publication Date
Tue Aug 16 2016
Journal Name
International Journal Of Computer Applications
Experimental Study of CLARK-Y Smoothed Inverted Wing with Ground Effect
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