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alkej-333
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
Tue Sep 01 2009
Journal Name
Al-nahrain Journal Of Science
Colorimetric assay of aspirin using modified method
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In this research, we did this qualitative and quantitative study in order to improve the assay of aspirin colorimetrically using visible spectrophotometer. This method depends on aqueous hydrolysis of aspirin and then treating it with the ferric chloride acidic solution to give violet colored complex with salicylic acid, as a result of aspirin hydrolysis, which has a maximum absorption at 530nm. This procedure was applied to determine the purity of aspirin powder and tablet. The results were approximately comparative so that the linearity was observed in the high value of both correlation coefficient (R= 0.998) and Determination Coefficient or Linearity (R2= 0.996) while the molar absorpitivity was 1.3× 103 mole

Publication Date
Sun Oct 01 2017
Journal Name
Journal Of Engineering
Improvement of Gypseous Soil Using Cutback Asphalt
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Gypseous soils are widely distributed and especially in Iraq where arid area of hot climatic is present. These soils are considered as problematic soils; therefore this work attends to improve the geotechnical properties of such soil and reduce the dangers of collapse due to wetting process. In this research, undisturbed soil sample of 30 % gypsum content from Karbala city is used. The Single Oedometer collapse test is used in order to investigate the collapse characteristics of natural soil and after treatment with 3%, 6%, 9%, 12% and 15% of Cutback Asphalt. Moreover, two selected additive percentages (9% and 12%) are used to evaluate the suitability of using the Cutback Asphalt for improvement of the bearing capacity o

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Publication Date
Wed Jan 01 2003
Journal Name
Tikrite Jour.of Eng.sci.
Agglomeration of zeolite type 13x using bentonite
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Publication Date
Fri Mar 01 2019
Journal Name
Spatial Statistics
Efficient Bayesian modeling of large lattice data using spectral properties of Laplacian matrix
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Spatial data observed on a group of areal units is common in scientific applications. The usual hierarchical approach for modeling this kind of dataset is to introduce a spatial random effect with an autoregressive prior. However, the usual Markov chain Monte Carlo scheme for this hierarchical framework requires the spatial effects to be sampled from their full conditional posteriors one-by-one resulting in poor mixing. More importantly, it makes the model computationally inefficient for datasets with large number of units. In this article, we propose a Bayesian approach that uses the spectral structure of the adjacency to construct a low-rank expansion for modeling spatial dependence. We propose a pair of computationally efficient estimati

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Publication Date
Wed Jun 30 2021
Journal Name
Gsc Biological And Pharmaceutical Sciences
Differences in some cranial bones between two Cyprinidae species, Common carp Cyprinus carpio (Linnaeus, 1758) and Crucian Carp Carassius carassius (Linnaeus, 1758) Collected from Tigris River, Iraq
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The present study attempts to identify some of the differences between the skull bones of two species Cyprinus carpio and Carassius carassius, which belong to the Cyprinidae family. The study is a taxonomic diagnostic study between the two species which are considered local fish abundant in the Iraqi aquatic environment

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Publication Date
Wed Mar 01 2023
Journal Name
Journal Of Engineering
Directive and Steerable Radiation Pattern using SASPA Array
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This work examines the ability of a special type of smart antenna array known as Switched Active Switched Parasitic Antenna (SASPA) to produce a directive and electronically steerable radiation pattern. The SASPA array consists of antenna elements that are switchable between active and parasitic states by using P-Intrinsic-N (PIN) diodes. The active element is the element that is supplied by the radio frequency while short-circuiting the terminals of an element in the array results in a parasitic element. Due to the strong mutual coupling between the elements, a directional radiation pattern with high gain and a small beamwidth can be produced with only one active element operating at a time. By changing the parasitic state to the active

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Publication Date
Wed Jun 01 2011
Journal Name
Political Sciences Journal
السياسة الروسية في الشرق الاوسط الكبير او (فن اقامة علاقات الصداقة مع كل دول العالم )
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السياسة الروسية في الشرق الاوسط الكبير او (فن اقامة علاقات الصداقة مع كل دول العالم)

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Publication Date
Wed Dec 01 2010
Journal Name
Journal Of Economics And Administrative Sciences
مقارنة بين طرائق تقدير معالم الانحدار عند وجود مشكلة عدم تجانس التباين مع التطبيق العملي
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In this research weights, which are used, are estimated using General Least Square Estimation to estimate simple linear regression parameters when the depended variable, which is used, consists of two classes attributes variable (for Heteroscedastic problem) depending on Sequential Bayesian Approach instead of the Classical approach used before, Bayes approach provides the mechanism of tackling observations one by one in a sequential way, i .e each new observation will add a new piece of information for estimating the parameter of probability estimation of certain phenomenon of Bernoulli trials who research the depended variable in simple regression  linear equation. in addition to the information deduced from the past exper

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Publication Date
Sun Jan 01 1995
Journal Name
كلية العلوم / جامعة بغداد
تحضير ودراسة طيفية وحرارية لمعقدات بعض العناصر الإنتقالية مع ليكانـــــد 4- (2- بريديل آزو)- ريزورسينول
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لقد حضر في هذا البحث عدد من المعقدات الجديدة لبعض ايونات العناصر الانتقالية وهي كل من Fe(II) , Fe(III) , Co(II) , Ni(II) , Cu(II) و Zn(II) مع الكاشف العضوي -4 ( -2 بريديل آزو ) ريزورسينول المعروف ب (PAR) . حيث تم التحضير بعد تثبيت الظروف المثلى من دالة حامضية وتركيز مولاري بوساطة أطياف الاشعة فوق البنفسجية – المرئية لمحاليل مزج الايونات الفلزية مع محاليل الكاشف العضوي اعلاه ولمدى واسع من الدالة الحامضية والتركيز المولارية الخاضعة لقانو

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Publication Date
Mon Nov 19 2018
Journal Name
Arab Science Heritage Journal
المجتمع المجتمع المدني في الفكر السياسي الإسلامي مقاربة فكرية مع نظريات الحكم الأساسية في الإسلام
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   This research is entitled (civil society in Islamic political thought) which is an intellectual approach with theories of governance in Islam) to be as an attempt to clarify the confusion between mandatory and governorship text basis, and the extent of the nation’s movement within the framework of guiding to translate requirements of the responding towards the civil state project through civil visions according to the Islamic perspective.

      In other words, It is the relationship of man and society in one hand and with an authority with other hand , according to an attempt vision that is to emphasize that Islamic religion can manage modern society and can prove legal philosophical reason

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