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State-of-the Art-Powerhouse, Dam Structure, and Turbine Operation and Vibrations
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Dam and powerhouse operation sustainability is a major concern from the hydraulic engineering perspective. Powerhouse operation is one of the main sources of vibrations in the dam structure and hydropower plant; thus, the evaluation of turbine performance at different water pressures is important for determining the sustainability of the dam body. Draft tube turbines run under high pressure and suffer from connection problems, such as vibrations and pressure fluctuation. Reducing the pressure fluctuation and minimizing the principal stress caused by undesired components of water in the draft tube turbine are ongoing problems that must be resolved. Here, we conducted a comprehensive review of studies performed on dams, powerhouses, and turbine vibration, focusing on the vibration of two turbine units: Kaplan and Francis turbine units. The survey covered several aspects of dam types (e.g., rock and concrete dams), powerhouse analysis, turbine vibrations, and the relationship between dam and hydropower plant sustainability and operation. The current review covers the related research on the fluid mechanism in turbine units of hydropower plants, providing a perspective on better control of vibrations. Thus, the risks and failures can be better managed and reduced, which in turn will reduce hydropower plant operation costs and simultaneously increase the economical sustainability. Several research gaps were found, and the literature was assessed to provide more insightful details on the studies surveyed. Numerous future research directions are recommended.

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Publication Date
Tue Sep 28 2021
Journal Name
Journal Of The College Of Education For Women
An Estimated Answer of a Condition between the Interpretive Structure and Surface Structure: Al-Qurtubi’s Tafseer as a Model: عمر عقلة خليف الدعجة
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This present work is concerned with one of the syntactic issues that has been researched by many linguists, grammarians, and specialists in Islamic studies, the estimated answer to a condition. However, this topic is researched this time by examining Imam Al-Qurtbi’s opinions in interpreting related ayas from the holly Quraan in his book (Collector of Quranic Rules) or its transliteration (Al-Jami’ Li Ahkam Al-Quran). Such a step involves commenting on, tracking what Al-Qurtbi said in this regard, discussing it from the points of view of other grammarians, and judging  it accordingly, taking into account the apparent surface structures of the examples collected. To achieve this objective, the inductive analytical approach has be

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Publication Date
Wed Jul 01 2015
Journal Name
Political Sciences Journal
Article The reality of the settlements in the occupied West Bank, and its impact on the future of the Palestinian state
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الخلاصة

تتناول هذه الورقة مخططات وسياسات الاستيطان في الضفة الغربية والقدس الشرقية منذ العام 1967، عبر سياسات قادها حزب العمل وأكملها حزب الليكود وكاديما وبقية الأحزاب الإسرائيلية، تلك السياسات التي استهدفت فرض السيطرة السياسية الكاملة على الأرض، وما نتج عن ذلك من سيطرة حصرية على الأرضوتقييد استخداماتها، ومحاصرة الوجود الفلسطيني والتضييق عليه، وتحويل مراكز ال

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Publication Date
Mon Mar 25 2019
Journal Name
Al-academy
Educational -Learning Design in the Achievement and Motivation of Students in the High School towards Art Education: كنعان غضبان حبيب
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  The present study aimed at ((building an educational -learning design based on the theory of Merrill in (CDT) and measuring the effectiveness of this design in the motivation and achievement of the high school fifth grade students to art education in the subject of the history of modern art)). The research community is made of fifth grade preparatory students in the secondary school of Umm Ayman in the Directorate of Education of Baghdad / Ar-Rusafa in a simple random way. The study sample (58 students) was chosen from section (e) to study according to Merrill theory (CDT) and section (d) to study according to the traditional way.
The pilot design of the control and experimental equivalent groups that have partial control in t

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Publication Date
Mon Oct 01 2012
Journal Name
Iraqi Journal Of Physics
Effects of copper doping and annealing on the structure and optical properties of ZnxCdx-1S thin films
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Effect of copper doping and thermal annealing on the structural and optical properties of Zn0.5Cd0.5S thin films prepared by chemical spray pyrolysis have been studied. Depositions were done at 250°C on glass substrate. The structural properties and surface morphology of deposited films were studied using X-ray diffraction (XRD) and photomicroscope (PHM) techniques. XRD studies reveal that all films are crystalline tetragonal structure. The film crystallinity are increased with 1% Cu-doping concentration and also increased for the films annealed at 300°C than the other studied cases. The lattice constant 'a' and 'c' varies with doping concentrations from 5.487Å to 5.427Å and 10.871Å to 10.757Å respectively. The grain size attained

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Publication Date
Thu Oct 01 2015
Journal Name
Al-academy
When Krochh aesthetic implications and their impact in raising the artistic and aesthetic taste among the students of the Department of Art Education: صلاح رهيف أمير
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The goal of current research to:1 - Know when aesthetic implications (Korchh)2 - To form the structure of systemic indicators and results that reflect the visions of intellectual, philosophical and aesthetic art for this study.The theoretical framework for the study of the search for the meaning of beauty, definition ( Krochh) being a philosopher, his views, his own aesthetic philosophy, knowledge, art and beauty, as well as a subject of artistic and aesthetic taste and Study in Art Education.The goals have been achieved during the search of Investigation theoretical framework for the search, which tried (INT) to form a clear vision check the second goal by the indicators reached.In light of this, the researcher recommended the need for

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Publication Date
Fri Sep 30 2022
Journal Name
Industrial Engineering & Management Systems
Optimizing the Complex Systems Reliability Using Mixed Strategy in Ultra-fast Gas Turbine Protection System
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Publication Date
Thu Oct 01 2020
Journal Name
Biochemical And Cellular Archives
MORPHOLOGICAL DESCRIPTION AND HISTOLOGICAL STRUCTURE OF THE JEJUNUM IN THE IRAQI BLACK PARTRIDGE (FRANCOLINUS FRANCOLINUS)
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Publication Date
Thu Oct 01 2020
Journal Name
Biochemical And Cellular Archives
MORPHOLOGICAL DESCRIPTION AND HISTOLOGICAL STRUCTURE OF THE JEJUNUM IN THE IRAQI BLACK PARTRIDGE (FRANCOLINUS FRANCOLINUS)
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Scopus
Publication Date
Thu Jan 07 2016
Journal Name
International Journal Of Innovative Research In Science, Engineering And Technology
Effect Of thickness On The Structure And Electrical Conductivity Properties Of CuInSe2 Thin Films
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The influence of different thickness (500,750, and 1000) nm on the structure properties electrical conductivity and hall effect measurements have been investigated on the films of copper indium selenide CuInSe2 (CIS) the films were prepared by thermal evaporation technique on glass substrates at RT from compound alloy. The XRD pattern show that the film have poly crystalline structure a, the grain size increasing with as a function the thickness. Electrical conductivity (σ), the activation energies (Ea1,Ea2), hall mobility and the carrier concentration are investigated as function of thickness. All films contain two types of transport mechanisms of free carriers increase films thickness. The electrical conductivity increase with thickness

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Publication Date
Tue Jan 08 2019
Journal Name
Iraqi Journal Of Physics
Effect of thickness on the structure, morphology and A.C conductivity of Bi2S3 thin films
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Thin films samples of Bismuth sulfide Bi2S3 had deposited on
glass substrate using thermal evaporation method by chemical
method under vacuum of 10-5 Toor. XRD and AFM were used to
check the structure and morphology of the Bi2S3 thin films. The
results showed that the films with law thickness <700 nm were free
from any diffraction peaks refer to amorphous structure while films
with thickness≥700 nm was polycrystalline. The roughness decreases
while average grain size increases with the increase of thickness. The
A.C conductivity as function of frequency had studied in the
frequency range (50 to 5x106 Hz). The dielectric constant,
polarizability showed significant dependence upon the variation of
thic

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