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Active Vibration Suppression of Smart Cantilever Beam with Sliding Mode Observer Using Two Piezoelectric Patches
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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.

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Publication Date
Sat Jan 01 2022
Journal Name
Journal Of Engineering
A Review on Expansive Soils Stabilized with Different Pozzolanic Materials
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Soils that cause effective damages to engineer structures (such as pavement and foundation) are called problematic or difficult soils (include collapsible soil, expansive soil, etc.). These damages occur due to poor or unfavorited engineering properties, such as low shear strength, high compressibility, high volume changes, etc. In the case of expansive soil, the problem of the shrink-swell phenomenon, when the soil reacts with water, is more pronounced. To overcome such problems, soils can be treated or stabilized with many stabilization ways (mechanical, chemical, etc.). Such ways can amend the unfavorited soil properties. In this review, the pozzolanic materials have been selected to be presented and discussed as chem

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Publication Date
Sun Jun 30 2019
Journal Name
Journal Of The College Of Education For Women
Traumatic Symptoms and Psychological Reactions Associated with Earthquakes in Iraq
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The study aims to identify the Traumatic Symptoms (physiological, emotional, and cognitive) of earthquakes among the targeted sample; it also aims to identify the significant differences between psychological, emotional, and cognitive traumatic symptoms of earthquakes according to the gender and age of participants. The study additionally seeks to identify thepsychological positive-negative reactions associated with earthquakes according to gender and age of the participants. To measure the traumatic symptoms of earthquakes, a 4-point Likert scale questionnaire with (20) items (questions) accompanied with a 4-point Likert scale questionnaire with (18) items (questions) were used to measure the Psychological positive-n

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Publication Date
Sun Dec 07 2014
Journal Name
Baghdad Science Journal
Is serum amylase normal in women with polycystic ovarian syndrome?
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Background : Polycystic ovary syndrome (PCOS) is the most common cause of infertility in reproductive-age women , it is an important harbinger of metabolic disorders. It has been reported that hyperamylasemia can be used as marker of ovarian cancer patients . The current study was conducted to evaluate amylase activity and to estimate the correlation of this enzyme with insulin and insulin resistance in PCOS patients. Methods: This study was conducted on forty five patients with PCOS in comparison to twenty five women as control. Fasting blood sample was taken from each subject and analyzed for amylase activity , FSH,LH, Insulin , proteins, and blood sugar , meanwhile insulin resistance was determined by HOMA-IR index. Results: The result

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Publication Date
Tue Jan 16 2018
Journal Name
International Journal Of Science And Research
Some Biochemical Assays in Hemodialysis Patients with Chronic Hepatitis C
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Abstract: The present study aimed to evaluate calcium, potassium, albumin, protein, creatinine, urea, uric acid levels, and the level of total sialic acid in the sera of patients with chronic renal failure who had been infected with Hepatitis C virus and in the sera of patients with chronic renal failure, and compare them with healthy volunteers. A total of 90 subjects with age 25-55 years, were divided into three groups. G1 represents 30 patients with chronic renal failure who had treated by dialysis and infected with chronic Hepatitis C virus (positive group). G2 represents 30 patients with chronic failure who had been treated by dialysis (negative group), while G3 represents 30 healthy volunteers (control group). The results showed

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Publication Date
Sun Apr 01 2018
Journal Name
Journal Of Educational And Psychological Researches
Personal Efficacy And Its Relationship With Mindfulness Among University Students
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The study seeks to examine the level of personal efficacy and its relation to mental alertness among university students. Besides, the statistically significant differences in regard of students' gender, and the correlation between male and female. To do this, the researcher adopted two scales: one to measure the personal efficacy which was made up by (abed al-jabaar, 2010) included (26) items, and the other to measure the mental alertness that designed by (abed Allah, 2012) included (36) items. A total of (120) student were selected randomly from three-different colleges at the Al-Mustansiriyah University for the academic year 2016-2017. The findings revealed there are no significant differences among students in regard of the personal

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Publication Date
Tue Dec 01 2015
Journal Name
Chemical Engineering Science
Airlift bioreactor for biological applications with microbubble mediated transport processes
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Publication Date
Mon Jul 10 2017
Journal Name
Asian Journal Of Pharmaceutical Research And Health Care
Health Literacy among Women with Different Educational States in Baghdad
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Health literacy is an important method used by the authorities to strengthen the health system. The aim of this study is to assess the knowledge of some basic health principles among women of different educational states. This is a crosssectional study, performed from December 2014 until January 2016, Baghdad. All candidates were: females > 18 years, neither medical staff nor students. They were divided into two groups: educated and uneducated. The sample included 213 women, there were 112 educated and 101 uneducated women. Regarding educated group, accurate answers regarding route of transmission of typhoid fever was 73.2% in educated subjects vs. 49.5% in uneducated subjects. Main source of information for both groups was p

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Publication Date
Sun Dec 31 2000
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Heat Transfer in Bubble Column Contactors with immersed Coiled Heater
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Publication Date
Fri Jul 21 2023
Journal Name
Journal Of Engineering
Laminar Natural Convection in nonrectangular Enclosure with and without Fins
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In the present work, steady, laminar natural convection in nonrectangular enclosures is analyzed numerically with and without fin. Vertical walls insulated while horizontal walls maintained isothermal at different temperature and the fin was placed on horizontal surface. The length of fin was equal (B/L=0.22, 0.44 and 0.66) and thickness of fin was constant. Various parameters are studied: Rayleigh number (from 104 to 107 ), Prandtl number (0.7), number of fin change from (1-3) and aspect ratio (H/L= 0.15 to 0.5). The problem is formulated in terms of the vorticity-stream function procedure. A numerical solution based on program in Fortran 90 with Tec plot program. The finite difference method is used. Streamlines and isotherms are prese

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Publication Date
Tue Dec 01 2020
Journal Name
Periodicals Of Engineering And Natural Sciences
Constructing a new mixed probability distribution with fuzzy reliability estimation
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This paper deals with constructing mixed probability distribution from mixing exponential

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