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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
Wed Jun 14 2023
Journal Name
Al-academy
The Written Text in Conceptual Art (An Analytical Study)
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The tagged research problem (the outputs of the written text in conceptual art) dealt with a comparative analytical study in the concept of conceptual art trends (land art - body art - art - language).

The study consisted of four chapters. The first chapter dealt with the theoretical framework, which was represented in presenting (the research problem), which raised the following question: What is the role of the written text in the transformations of the conceptual arts?

The first chapter included (the importance of research) and (research objectives) seeking to conduct comparative research in the written text within the trends of conceptual art as a moving phenomenon in art, and to reveal the variable written text in the

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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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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
Fri Mar 01 2013
Journal Name
Journal Of Economics And Administrative Sciences
Measure and evaluate the return and risk formulas of Islamic Finance: Empirical study of the state of Jordan Islamic Bank and Islamic Arab International Bank
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    The study aims to measure and evaluate the return and the risk formulas of Islamic finance of Jordan during the period (2000 – 2009) according of increasing  importance of these banks in recent and coming years to face challenges to maximize returns and minimize risks through financing with  Islamic formula to investigate of existence statistical significant  relationship between returns and risking Islamic bank , has been use of financial other statistical  measurement. Measuring return and risk of Islamic banks have not been widely considered ,except in few descriptive studies . The controversy among academic and professionals about hot to measure and evaluate a comprehe

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Publication Date
Sun Jul 03 2016
Journal Name
Journal Of Educational And Psychological Researches
The exploratory and Confirmatory Factorial structure for Riso-Hadson enneagram test indicator
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This  investigation was conducted to recognize the structure for (RHETI version 2.5  1999) by using exploratory and confirmatory factor analysis. Sample of (620) student of Al-Mustansrya University were administered the (RHETI).

The data of their responses was analyzed by using (PAF) and oblique rotating .

The findings explored (9) factors as one factor for each type and (184) items were loaded by the factors: (60) item for feeling center, (61) items for instinctive center and (63) items for thinking center.

Results of confirmatory factorial analysis supported a model designed by the researcher depended upon a theoretical views of Riso and Hudson

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Publication Date
Sun Mar 02 2008
Journal Name
Baghdad Science Journal
Study the Band Energy Structure and Absorption Coefficient for PbSe Thin Films
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The PbSe alloy was prepared in evacuated quarts tubs by the method of melt quenching from element, the PbSe thin films prepared by thermal evaporation method and deposited at different substrate temperature (Ts) =R.T ,373 and 473K . The thin films that deposited at room temperature (R.T=303)K was annealed at temperature, Ta= R.T, 373 and 473K . By depended on D.C conductivity measurements calculated the density of state (DOS), The density of extended state N(Eext) increases with increasing the Ts and Ta, while the density of localized state N(Eloc) is decreased . We investigated the absorption coefficient (?) that measurement from reflection and transmission spectrum result, and the effect of Ts and Ta on it , also we calculated the tai

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Publication Date
Thu Feb 28 2019
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Evaluating the Observing Internal System in the General State of Taxes and its Role in Increasing the Taxes Revenue
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The internal observing system is considered a cornerstone for the high management in all the systems. It aims at defending the things for waste and increasing efficient and application the rules and regulations and constrictions. To easier for the high management activity in the internal observing system which in presented and practiced and to what extent can depend on it. Thus it goes to evaluate the internal observing system periodically to check the weak points in that system so as the find out the mistake, in the construction of the system or mistake, by indication of the workers. The importance of this study is represented in the need of increasing the coactivity in the internal observing system so as to be in touch with the new tre

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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
Fri Dec 01 2017
Journal Name
Journal Of Computational And Theoretical Nanoscience
Three-Dimensional Seismic Response Analysis for a Rockfill Dam
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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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