Preferred Language
Articles
/
joe-145
Sliding Mode Vibration Suppression Control Design for a Smart Beam
...Show More Authors

Active vibration control is the main problem in different structure. Smart material like piezoelectric make a structure smart, adaptive and self-controlling so, they are effective in active vibration control. In this paper piezoelectric elements are used as sensors and actuators in flexible structures for sensing and actuating purposes, and to control the vibration of a cantilever beam by using sliding mode control. The sliding mode controller (SMC) is designed to attenuate the vibration induced by initial tip displacement which is equal to 15 mm.  It is designed based on the balance realization reduction method where three states are selected for the reduced model from the 24th states that describe the cantilever beam according to the FEM. These states are most controllable and observable. The stability and control performance for the proposed SMC are proved using candidate Lyapunov function and the equivalent control concept. The control spillover, which is the sources of instability, is completely avoided as ensured within the control performance proof.

            Numerical simulations are preformed to test the vibration attenuation ability of the proposed SMC. For 15 mm initial tip displacement, the piezoelectric actuator was found able to reduce the tip displacement to about (0.2) mm within (2.5 s), while it is equal to (3.5) mm with the open loop case. Moreover, the induced chattering in system response, due to the discontinuous control action, is removed by approximating the signum function by a continuous arctan function. As a result  a smoother response are obtained with the same control performance as can be shown in the sliding variable, the control input voltage and the tip displacement plots.

 

 

View Publication Preview PDF
Quick Preview PDF
Publication Date
Tue Jun 17 2025
Journal Name
Baghdad Science Journal
Utilizing an Atomic Force Microscopy with Continuous Flow Injection Analysis using NAG-4(sources)x3 with Three Solar Cells (NAG-4SX3-3D) Analyzer for Studying the Surface Morphology of the Precipitate of the Cyproheptadine-HCl and Loratadine
...Show More Authors

View Publication
Scopus (1)
Crossref (1)
Scopus Clarivate Crossref
Publication Date
Sat Oct 01 2022
Journal Name
Al–bahith Al–a'alami
LOCAL NEWS SOURCES IN THE IRAQI NEWSPAPERS: Local news sources in the Iraqi newspapers (An analytical study of local news sources In the newspaper Al-Zaman for the period from 1/6/2006 to 06/30/2006)
...Show More Authors

Local news is an important topic of the press because of its importance to readers. It touches their daily life in one way or another, which makes them interested in and followers of them. Hence the importance of local news, as it interests a wide segment of readers.
There are many sources of newspapers for obtaining local news, as these sources are distributed to the newspaper's own sources and external sources.

Self-sources are the newspaper's own sources, through which it is possible to obtain this news, such as the representatives of the newspaper and its correspondents and the journalists working in it. This is the example in this way.
The external sources are distributed to local and international news agencies and sa

... Show More
View Publication Preview PDF
Crossref
Publication Date
Wed Apr 30 2025
Journal Name
Journal Of Al-farabi For Humanity Sciences (jfhs)
Colonialism and Anticolonialism in English Fiction: A Study of Defoe’s Robinson Crusoe and H. G. Wells’ The Country of the Blind الاستعمار ومناهضته في الادب القصصي الإنجليزي: دراسة في رواية دانيل ديفو (روبنسون كروسو) وقصة هربرت جورج ويلز (بلد العميان)
...Show More Authors

Colonialism as a movement was very popular in Europe more than two centuries before. It aimed at controlling and exploiting several countries in Africa and Asia in addition to imposing their power and control on uninhabited islands. It received adherence and criticism as well. There also appeared activists and nations who stood against it and its practices. English novels discussed this notion greatly by pointing out the bad practices of the colonizers and how the colonized received them. This paper explores two narrative fictions that tackle the different aspects of the term. While Defoe, in Robinson Crusoe (1719), shows a colonial European figure who expresses his superiority, Wells, in “The Country of the Blind” (1904), deconstructs

... Show More
View Publication
Publication Date
Tue Mar 01 2016
Journal Name
Applied Research Journal
Response of R.C. Barriers Subjected to TNT Explosion Blast Loading
...Show More Authors

Reinforced concrete barriers have been commonly used in protecting the important building because the response of R.C. barriers subjected to blast loading is practically more acceptable than other materials used to build the barriers. In this study, the response of R.C. barriers was detected due to the blast effects caused by two charge weights (50 kg and 400 kg); ANSYS 14 was used to simulate the problem. A horizontal distance of 2 m between the explosive TNT charge and the front face of wall was taken. The pressure on the front face of the concrete barriers was measured at three levels. The R.C. barrier was entirely damaged when subjected to the blast effects caused by 400 kg TNT explosion bomb. However, the 50 kg TNT charge had

... Show More
Publication Date
Mon Jan 01 2018
Journal Name
Fme Transaction
The influence of frictional facing thickness on the contact pressure distribution of multi-disc dry clutches
...Show More Authors

Frictional heat is generated when the clutch starts to engag. As a result of this operation the surface temperature is increased rapidly due to the difference in speed between the driving and driven parts. The influence of the thickness of frictional facing on the distribution of the contact pressure of the multi-disc clutches has been investigated using a numerical approach (the finite element method). The analysis of contact problem has been carried out for a multiple disc dry clutch (piston, clutch discs, separators and pressure plate). The results present the distribution of the contact pressure on all tShe surfaces of friction discs that existed in the friction clutch system. Axisymmetric finite element models have been developed to ac

... Show More
View Publication
Scopus (9)
Crossref (9)
Scopus Clarivate Crossref
Publication Date
Sun Nov 01 2020
Journal Name
Journal Of Engineering
Nonlinear Finite Element Analysis of RCMD Beams with Large Circular Opening Strengthened with CFRP Material
...Show More Authors

This paper presents the non-linear finite element method to study the behavior of four reinforced rectangular concrete MD beams with web circular openings tested under two-point load. The numerical finite elements methods have been used in a much more practical way to achieve approximate solutions for more complex problems.  The ABAQUS /CAE is chosen to explore the behavior of MD beams. This paper also studies, the effect of both size and shape of the circular apertures of MD beams. The strengthening technique that used in this paper is externally strengthening using CFRP around the opening in the MD beams. The numerical results were compared to the experimental results in terms of ultimate load failure and displace

... Show More
View Publication Preview PDF
Crossref (3)
Crossref
Publication Date
Wed Jun 04 2025
Journal Name
Engineering, Technology & Applied Science Research
Investigating Fiber Reinforcement Effects on the Performance of Concrete Pavements under Repeated Load
...Show More Authors

Concrete pavements are essential to modern infrastructure, but their low tensile and flexural strengths can cause cracking and shrinkage. This study evaluates fiber reinforcement with steel and carbon fibers in various combinations to improve rigid pavement performance. Six concrete mixes were tested: a control mix with no fiber, a mix with 1% steel fiber (SF1%), a mix with 1% carbon fiber (CF1%), and three hybrid mixes with 1% fiber content: 0.75% steel /0.25% carbon fiber (SF0.75CF0.25), 0.25% steel /0.75% carbon fiber (SF0.25CF0.75), and 0.5% steel /0.5% carbon fiber ((SF0.5CF0.5). Laboratory experiments including compressive, flexural, and splitting tensile strength tests were conducted at 7, 28, and 90 days, while Finite Element Analys

... Show More
View Publication
Scopus Crossref
Publication Date
Sun Aug 18 2019
Journal Name
Proceedings Of Mechanical Engineering Research Day 2019,
Study of sound absorption of micro perforated panel with visco-thermal effects
...Show More Authors

Publication Date
Tue Mar 30 2021
Journal Name
Baghdad Science Journal
Experimental Evidence of Chaotic Resonance in Semiconductor Laser
...Show More Authors

In this paper, an experimental study has been conducted regarding the indication of resonance in chaotic semiconductor laser.  Resonant perturbations are effective for harnessing nonlinear oscillators for various applications such as inducing chaos and controlling chaos. Interesting results have been obtained regarding to the effect of the   chaotic resonance by adding the frequency on the systems. The frequency changes nonlinear dynamical system through a critical value, there is a transition from a periodic attractor to a strange attractor. The amplitude has a very relevant impact on the system, resulting in an optimal resonance response for appropriate values related to correlation time. The chaotic system becomes regular under

... Show More
View Publication Preview PDF
Scopus (4)
Scopus Clarivate Crossref
Publication Date
Wed Jun 30 2010
Journal Name
Al-kindy College Medical Journal
Evaluation the Effectiveness of Impregnated Net in Reducing Leishmaniasis Incidence: Diala-Iraq
...Show More Authors

Background: Leishmaniasis is important public
health problem owing to its impact on morbidity
and mortality and difficulties in application of
effective control measures.
Objective: The aim of the study is to evaluate the
using of impregnate bed nets in the control of
leishmaniasis.
Methods: The study was conducted throughout
the years 2004 and 2005, in Diala Governorate
(about 60km north-east Baghdad). This is the first
study in Iraq for evaluation of the impregnated bed
net in control of leishmaniasis. Two villages were
selected to achieve this aim. The nets were
distributed for the first village to be used by their
population. The second village was served as
control.

Results: The

... Show More
View Publication Preview PDF