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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
Fri Mar 22 2019
Journal Name
Journal Of Pharmaceutical Sciences And Research
Evaluation of the efficacy of caries removal using papain gel (Brix 3000) and smart preparation bur (in vivo comparative study)‏
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Publication Date
Tue Jan 01 2008
Journal Name
Journal Of Engineering
USING FUZZY LOGIC CONTROLLER FOR A TWO- TANK LEVEL CONTROL SYSTEM
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This paper presents a fuzzy logic controller for a two-tank level control system, which is a process with a dead time. The fuzzy controller is a proportional-integral (PI-like) fuzzy controller which is suitable for steady state behavior of the system. Transient behavior of the system was improved without the need for a derivative action by suitable change in the rule base of the controller. Simulation results showed the step response of the two-tank level control system when this controller was used to control this plant and the effect of the dead time on the response of the system.

Publication Date
Thu May 28 2020
Journal Name
Iraqi Journal Of Science
Comparison between Horizontal and Vertical OFETs by Using Poly (3-Hexylthiophene) (P3HT) as an Active Semiconductor Layer
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In this paper, a comparison between horizontal and vertical OFET of Poly (3-Hexylthiophene) (P3HT) as an active semiconductor layer (p-type) was studied by using two different gate insulators (ZrO2 and PVA). The electrical performance output (Id-Vd) and transfer (Id-Vg) characteristics were investigated using the gradual-channel approximation model. The device shows a typical output curve of a field-effect transistor (FET). The analysis of electrical characterization was performed in order to investigate the source-drain voltage (Vd) dependent current and the effects of gate dielectric on the electrical performance of the OFET. This work also considered the effects of the capacitance semiconductor on the performance OFETs. The value

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Publication Date
Wed Mar 15 2023
Journal Name
Al-academy
Active design and its principles in industrial product design
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 The problem of the research came through the following question (what is the effectiveness of active design in contemporary industrial products), and it emphasized the importance of research to make society with its members in a positive state of activity, and what can help the industrial product design to achieve this, but the goal of the study is (determining the characteristics and principles of design Active and its effectiveness in the industrial product), and the study was determined by industrial products related to daily, recreational and sports activity, The researcher relied on a form to determine the axes of analysis for the sample models, in order to reach the results of the research, the most important of which are: Realiz

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Publication Date
Tue Jun 11 2019
Journal Name
Iraqi Journal Of Pharmaceutical Sciences ( P-issn 1683 - 3597 E-issn 2521 - 3512)
Evaluating Health-Related Quality of Life (HRQoL) in Iraqi Adult and Pediatric Patients with Beta-Thalassemia Major Using Two Different Iron Chelation Therapies
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Publication Date
Sun Dec 12 2010
Journal Name
Alustath Journal For Human And Social Sciences
Suggested Approach to deal with Multicollinearity Problem – with Application –
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This research introduce a study with application on Principal Component Regression obtained from some of the explainatory variables to limitate Multicollinearity problem among these variables and gain staibilty in their estimations more than those which yield from Ordinary Least Squares. But the cost that we pay in the other hand losing a little power of the estimation of the predictive regression function in explaining the essential variations. A suggested numerical formula has been proposed and applied by the researchers as optimal solution, and vererifing the its efficiency by a program written by the researchers themselves for this porpuse through some creterions: Cumulative Percentage Variance, Coefficient of Determination, Variance

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Publication Date
Mon Dec 18 2017
Journal Name
Al-khwarizmi Engineering Journal
Conversion of Lignocellulosic Material Into Fermentable Sugars
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Enzymatic hydrolysis process of lignocellulosic biomass materials is difficult because of inherent structural features of biomass, which represents barriers that prevent complete hydrolysis; therefore, pretreatment techniques are necessary to render biomass highly digestible in enzymatic hydrolysis process. In this research, (non?) oxidative short-term lime pretreatment of willow wood was used. A weight of  11.40 g of willow wood was mixed with an excess of calcium hydroxide (0.4 g Ca(OH)2/g raw biomass) and water loading (15 g/g raw biomass). Lime pretreatment was carried out for various periods of time including 1, 2, 3.5, 5 and 6 h, with temperatures at 100, 113, 130, 147 and 1600C, and oxygen pressures as o

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Publication Date
Wed Feb 01 2017
Journal Name
Journal Of Economics And Administrative Sciences
The added value of the knowledge assets using a scale (VAIC) in a sample of the industrial sector companies
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The sustainable competitive advantage for organizations is one of the requirements for value creation, which centered on the possession of scarce resources that achieve maximum flows to invest in intellectual capital, if what has been interest in them, measured and employed the way properly and style, so I figured the need for new technologies to enable organizations to measure the intellectual and physical assets and to assess its performance accordingly, so it sheds search light on the measurement of the added value of existing knowledge using the standard value-added factor is the intellectual (value added intellectual coefficient) (VAIC) and to develop a set of assumptions about the extent of the difference between the sample

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Publication Date
Wed Jun 20 2018
Journal Name
Al-academy
Form and content in book covers designs
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   Despite the development in the fields of communication and informatics, the book remains its distinguished presence and popular popularity as it is the oldest means to obtain knowledge, addressing the vast majority of society in different levels and levels of knowledge and culture. The design of the cover book portal and the structure of semolina semantic including the elements of construction and typography contribute to the activation of the relationship between form and content, and here lies the importance of this relativity and its role in enhancing the communicative dimension of the design of the book cover, and cast a shadow on the promotional and marketing effectiveness. Hence the importance of research, but the prob

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Publication Date
Thu Jul 21 2022
Journal Name
Al-academy
خصائص الشكل في منحوتات مرتضى حداد
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يهتم البحث بدراسة الشكل في منحوتات الفنان مرتضى حداد ، والبحث عن خصائصه الفنية، وعلى وفق ذلك تمت صياغة عنوان البحث بالصيغة آلاتية: خصائص الشكل في منحوتات الفنان مرتضى حداد. شيد البحث على أربعِ مباحث؛ وتتقدمها مقدمة ثُبتت فيها مشكلة البحث التي قام على أساسها هذا البحث ، وكذلك أهمية البحث وبيان مدى الحاجة إليه ، وكذلك تحديد هدف البحث وهو الكشف عن خصائص الشكل في منحوتات الفنان مرتضى حداد ، فضلاً عن ح
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