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Sliding Mode Vibration Suppression Control Design for a Smart Beam
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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.

 

 

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Publication Date
Mon Dec 22 2025
Journal Name
Sport Culture
Some bio-motor abilities and their relationship to the skill of standing on the hands followed by the forward roll on the mat of floor movements in artistic gymnastics for women
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The research consists of five chapters, and in the first chapter, it addresses the introduction and importance of the research, where the researcher explained the importance of bio-motor abilities and their role in achieving a high level through their connection to the skill performance of standing on the hands followed by the forward roll, and the research problem: Do these bio-motor abilities have an impact on the level of skill performance? Handstand followed by forward roll.

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Publication Date
Tue Jan 02 2018
Journal Name
Journal Of Educational And Psychological Researches
Psychological social conflict and its relation with family parental style for adolescences from the intermediate stage student at governmental Hail school, in the light of economical levels and sex variables .KSA
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The current research attempts to examine the relationship between social-psychological conflict and their relation to family upbringing approaches among the adolescents of intermediate stage according to sex and economical level. To do this, the researcher prepared a questionnaire to measure social-psychological conflict that consisted of (32) item divided on four dimensions, and also she prepared a questionnaire to measure family upbringing approaches which composed of (28) item divided on four dimensions. The sample was (260) male and female student from intermediate stage chosen randomly. The results revealed that there were significant differences between social-psychological conflict which went to male, there was a negative correlat

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Publication Date
Sat Jun 01 2024
Journal Name
Baghdad Science Journal
Synthesis, Characterization, Thermal Analysis Study and Antioxidant Activity for Some Metal Ions Cr (III), Fe (III), Mn (II) and Pd(II) Complexes with Azo Dye Derived from p-methyl-2-hydroxybenzaldehyde
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ليكاند ازو جديد. 4-((3-formyl-2-hydroxyphenyl)diazenyl)-N-(5-methylisoxazol-3-yl)benzenesulfonamide, الليكاند المحضر استعمل لتحضير معقدات من ايونات معادن مختلفة مثل الكروم الثلاثي والمنغنيز الثنائي والحديد الثلاثي  والبلاديوم الثنائي بنسب مولية (1:1) ( ليكاند : فلز) نتائج التشخيص للمركبات يتقنيات مطيافية الاشعة فوق البنفسجية الاشعة تحت الحمراء الرنين النووي المغناطيسي البروتوني والكربوني وطيف الكتلة والتحليل الدقيق للعناصر ومحتوى الفلز وال

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Scopus (3)
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Publication Date
Tue Feb 12 2019
Journal Name
Iraqi Journal Of Physics
Calculated the diffuse and direct parts of global solar radiation in Baghdad city for the period (1983-2005) depending on clearness index by applying the two world models of Liu -Jordan
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In this paper solar radiation was studied over a region of Baghdad (Latitude 33.3o and longitude 44.4o). The two parts of global solar radiation: diffuse and direct solar radiation were estimated depending on the clearance index of measured data (Average Monthly mean global solar radiation). Metrological data of measured (average monthly mean diffuse and direct solar radiation) were used to comparison the results and show the agreement between them. Results are determined by applying Liu and Jordan two models (1960). Excel 2007program is used in calculation, graphics and comparison the results.

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Crossref
Publication Date
Thu May 31 2012
Journal Name
Al-khwarizmi Engineering Journal
Restrained Edges Effect on the Dynamics of Thermoelastic Plates under Different End Conditions
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Frequency equations for rectangular plate model with and without the thermoelastic effect for the cases are: all edges are simply supported, all edges are clamped and two opposite edges are clamped others are simply supported.   These were obtained through direct method for simply supported ends using Hamilton’s principle with minimizing Ritz method to total energy (strain and kinetic) for the rest of the boundary conditions. The effect of restraining edges on the frequency and mode shape has been considered. Distributions temperatures have been considered as a uniform temperature the effect of developed thermal stresses due to restrictions of ends conditions on vibration characteristics   of a plate with different

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Publication Date
Tue Jan 23 2018
Journal Name
Suleyman Demİrel University
ANALYZING POSTGRADUATE STUDENTS' USE OF PRAGMATIC FEATURES AND ARGUMENTATION IN THESIS WRITING: A CORPUS-BASED STUDY تحليل استخدام طلبة الدراسات العليا للسمات التداولية و الحجج في كتابة الرسائل العلمية : دراسة تعتمد تحليل البيانات المحوسبة
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This study addresses the issue of academic writing in English by comparing pragmatic argumentation in the writing of 40 graduate students studying at Iraqi universities (SSIU) with the writing of 40 graduate students studying at American universities (SSAU). In these 80 theses, six selected aspects of academic writing were analyzed: (a) paragraph structure, (b) length and construction of sentences, (c) organization of information in sentences, (d) vocabulary, (e) topic sentences, and (f) discourse markers. This study seeks to go beyond the traditional and often onedimensional analysis of pragmatics of argumentation in English academic writing to distinguish and describe different aspects of academic writing and their results when used by EF

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Publication Date
Mon Dec 22 2025
Journal Name
Journal Of Business Economics For Applied Research
The Relationship between Authentic leadership and Knowledge Sharing through the mediating Role of Creative work Behaviors: An applied study on a sample of managers in the Ministry of Labor and Social Affairs in Baghdad
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Publication Date
Wed May 10 2017
Journal Name
Journal Of The College Of Languages (jcl)
РОЛЬ СРЕДСТВ НАГЛЯДНОСТИ В ПРОЦЕССЕ ОБУЧЕНИЯ РУССКОМУ ЯЗЫКУ КАК ИНОСТРАННОМУ В ИРАСКОЙ АУДИТОРИИ The Role of the Use of Visual Aids in the Process Of Learning Russian Language in Lraq as a Foreign Language
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В статье рассматриваются понятие наглядности и ее классификация, эффективное применение принципа наглядности, возможность и преимущество использования наглядности и современные инструменты ее реализации в ираке.

 

Вследствие глобальных изменений во всем мире изменилась и роль иностранного языка в системе образования. Современный человек, шагающий в ногу со временем, не мыслит себя без зна

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Publication Date
Mon Jan 01 2018
Journal Name
Al–bahith Al–a'alami
Using Social Media sites by the Iraqi women and the Achieved The Use of Iraqi Women of Social Networking Sites and the Satisfactions Generated from Them.: A Survey Study of the City of Baghdad
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The problem of this research lies in the fact that there is a lack of accurate scientific perceptions about the size of the use of Iraqi women’s social networking sites and the motives behind this use and the expectations generated by them.
The goals of the research are as follows:
1- Determine the extent of Iraqi women’s use of social networking sites (Facebook, YouTube, twitter, and Instagram).
2- Investigative the motives behind the use of social networking sites by Iraqi women.
3- Detecting the repercussions of Iraqi women’s use of social networking sites (Facebook, you tube, twitter, and Instagram).
The research is classified as a descriptive one. The researchers use the survey methodology. The research commu

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Publication Date
Sun Jan 12 2025
Journal Name
Journal Of The Iraqia University
Conflict of Identities Among Immigrants: A Study of Jamaica Kincaid’s Lucy and Hassan Blasim’s Nightmares of Carlos Fuentes صراع الهويات بين المهاجرين: دراسة في قصة لوسي لجامايكا كينكايد وقصة حسن بلاسم كوابيس كارلوس فوينتس
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The struggle between two identities is a crucial subject everywhere. Some people travel abroad in quest of a new identity after struggling at home. People migrate and embrace a new identity for different reasons. They find themselves in a state of internal conflict as they navigate the tension between their newly adopted identities and their old ones. The individual is haunted and overwhelmed by their previous experiences. This research explores the universality of the subject matter by examining the motivations underlying the adoption of a new identity in a distinct geographical and temporal context. This paper examines the literary works of Kincaid's Lucy (1990) and Blasim's "The Nightmares of Carlos Fuentes" (2014). Kincaid’s pro

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