Preferred Language
Articles
/
alkej-333
Active Vibration Suppression of Smart Cantilever Beam with Sliding Mode Observer Using Two Piezoelectric Patches
...Show More Authors

This paper presents a vibration suppression control design of cantilever beam using two piezoelectric ‎patches. One patch was used as ‎an actuator element, while the other was used as a sensor. The controller design was designed via the balance realization reduction method to elect the reduced order model that is most controllable and observable. ‎the sliding mode observer was designed to estimate six states from the reduced order model but three states are only used in the control law. Estimating a number of states larger than that used is in order to increase the estimation accuracy. Moreover, the state ‎estimation error is proved bounded. An ‎optimal LQR controller is designed then using the ‎estimated states with the sliding mode observer, to ‎suppress the vibration of a smart cantilever ‎beam via the piezoelectric elements. The control spillover problem was avoided, by deriving an avoidance ‎condition, to ensure the ‎asymptotic stability for the proposed vibration ‎control design. ‎The numerical simulations were achieved to ‎test the vibration attenuation ability of the ‎proposed optimal control. For 15 mm initial tip ‎displacement, the piezoelectric actuator found ‎able to reduce the tip displacement to about 0.1 ‎mm after 4s, while it was 1.5 mm in the ‎open loop case.  The current experimental results showed a good performance of the proposed LQR control law and the sliding mode observer, as well a good agreement with theoretical results.

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Thu Dec 23 2021
Journal Name
Iraqi Journal Of Science
Characterization of Cr2O3 Nanoparticles Prepared Using Cauliflower Extract by Two Methods
...Show More Authors

     Chromium oxide nanoparticles were synthesized using cauliflower extract by two methods: simple chemical method and the sol-gel method. These technologies are  new, environmentally friendly and cheap. Cauliflower contains plant materials and biomolecules (chromium, phenols, alkalis, vitamins, amino acids, quinones, etc. (that convert chromium chloride hexahydrate (CrCl3.6H2O) into chromium nanoparticles. The plant extracts also act as diluents, stabilizers and anti-caking agents. X-ray diffraction (XRD) analysis showed that the size of the crystals decreased from (36.1 to 57.8) nm  using the simple chemical method to (13.31 to 20.68) nm of Cr2O3 using sol-gel.

... Show More
View Publication Preview PDF
Scopus (1)
Crossref (1)
Scopus Crossref
Publication Date
Wed Dec 30 2009
Journal Name
Iraqi Journal Of Physics
Two-dimensional Crystallization of Silica nanospheres using Coplanar DC Electric field
...Show More Authors

Two-dimensional crystal has been achieved and controlled
with the aid of DC electric field applied between two electrodes at 5
millimeters separating distance between them. Sol-gel method has
been used to prepared nanosilica particle which used in this work as
well as TiO2 nanopaowder. The assembly of the silica particles is
due to the interaction between the electrical force, the particles
dipole, and the interaction between the particles themselves. When a
DC voltage is applied, the particles accumulated and crystallized on
the surface between the electrodes. The Light diffraction
demonstrates that the hexagonal crystal is always oriented with one
axis along the direction of the field. The particles disass

... Show More
View Publication Preview PDF
Publication Date
Tue Jan 01 2019
Journal Name
Ieee Access
Sensing Performance of Modified Single Mode Optical Fiber Coated With Nanomaterials-Based Ammonia Sensors Operated in the C-Band
...Show More Authors

View Publication
Scopus (13)
Crossref (17)
Scopus Clarivate Crossref
Publication Date
Fri Mar 18 2022
Journal Name
International Journal Of Health Sciences
Histological and Immunohistochemical Study of the Protective Effect of Virgin Coconut Oil on Cyclophosphamide-induced Immunotoxicity of the Spleen and Peyer’s Patches
...Show More Authors

Publication Date
Mon Mar 08 2021
Journal Name
Baghdad Science Journal
The structural and mechanical properties of ion beam
...Show More Authors

the structrual and mechanical properties of thin Ni films of different thicknesses deposited on coring glass substrate using lonbeam sputtering(IBS) technique under vacuum torr have been studied the TEM and electron

View Publication Preview PDF
Publication Date
Thu Feb 01 2024
Journal Name
Structures
Accelerating reliability analysis of deteriorated simply supported concrete beam with a newly developed approach: MCS, FORM and ANN
...Show More Authors

Reliability analysis methods are used to evaluate the safety of reinforced concrete structures by evaluating the limit state function 𝑔(𝑋𝑖). For implicit limit state function and nonlinear analysis , an advanced reliability analysis methods are needed. Monte Carlo simulation (MCS) can be used in this case however, as the number of input variables increases, the time required for MCS also increases, making it a time consuming method especially for complex problems with implicit performance functions. In such cases, MCS-based FORM (First Order Reliability Method) and Artificial Neural Network-based FORM (ANN FORM) have been proposed as alternatives. However, it is important to note that both MCS-FORM and ANN-FORM can also be time-con

... Show More
View Publication
Scopus (1)
Crossref (1)
Scopus Clarivate Crossref
Publication Date
Sun Jun 30 2019
Journal Name
Journal Of Engineering
Numerical Study of Fluid Flow and Heat Transfer Characteristics in Solid and Perforated Finned Heat Sinks Utilizing a Piezoelectric Fan
...Show More Authors

Numerical study is adapted to combine between piezoelectric fan as a turbulent air flow generator and perforated finned heat sinks. A single piezoelectric fan with different tip amplitudes placed eccentrically at the duct entrance. The problem of solid and perforated finned heat sinks is solved and analyzed numerically by using Ansys 17.2 fluent, and solving three dimensional energy and Navier–Stokes equations that set with RNG based k−ε scalable wall function turbulent model. Finite volume algorithm is used to solve both phases of solid and fluid. Calculations are done for three values of piezoelectric fan amplitudes 25 mm, 30 mm, and 40 mm, respectively. Results of this numerical study are compared with previous b

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Oct 02 2005
Journal Name
Journal Of The Faculty Of Medicine Baghdad
treatment of pityiasis versicolor with two weekly dose of systemic fluconazole
...Show More Authors

Background:

View Publication Preview PDF
Crossref
Publication Date
Sun Oct 02 2011
Journal Name
Journal Of The Faculty Of Medicine Baghdad
In Vitro Study of Mutagenicity and Genotoxicity of Some Bacterial Secretions associated with Bladder Tumors Tissues on Human Lymphocytes by Using Blood Tissue Culture Techniques
...Show More Authors

Background: Cytogenetic studies have been used to assess carcinogenic or mutagenic exposures and effects early in occupational, biological and environmental settings. Bacterial infection has not traditionally been considered asa major causes of cancer. Bacteria have been linked to cancer by two mechanisms: induction of chronic inflammation and production of carcinogenic bacterial metabolites.
Objective: Because of new concepts in relating infection with certain malignancies the present study is performed. Therefore this study was conducted to determine the effects of bacterial products associated with biopsies of bladder tumor on human lymphocytes tissue cultures in vitro. Moreover, if there is any relation between these products for

... Show More
View Publication Preview PDF
Crossref
Publication Date
Wed Jun 01 2022
Journal Name
Baghdad Science Journal
Kinetic, Isotherm and Thermodynamic Studies on the Ciprofloxacin Adsorption from Aqueous Solution Using Aleppo bentonite
...Show More Authors

          Aleppo bentonite was investigated to remove ciprofloxacin hydrochloride from aqueous solution. Batch adsorption experiments were conducted to study the several factors affecting the removal process, including contact time, pH of solution, bentonite dosage, ion strength, and temperature. The optimum contact time, pH of solution and bentonite dosage were determined to be 60 minutes, 6 and 0.15 g/50 ml, respectively. The bentonite efficiency in removing CIP decreased from 89.9% to 53.21% with increasing Ionic strength from 0 to 500mM, and it increased from 89% to 96.9% when the temperature increased from 298 to 318 K. Kinetic studies showed that the pseudo second-order model was the best in describing  the adsorption sys

... Show More
View Publication Preview PDF
Scopus (3)
Crossref (2)
Scopus Clarivate Crossref