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.
The laws of the three religions tend to extend the rules and foundations of coexistence, and this is achieved in achieving the values and principles that these laws have nourished in all societies.
Our research deals with a major problem that has broken out in our societies, namely (disturbing the balance of values and behavioral standard between people), and perhaps one of the greatest causes of the problem is to move away from the correct divine discourse and sound approach, as well as corruption of common sense and the violation of its rules and found principles in the hearts of people.
In the name of Allah, the Beneficent, the Merciful.
Praise be to Allah, Lord of the Worlds and peace and blessings on the honest and trustworthy (Muhammad) and his family and his divine good companions.
The Islamic clothing is one of the requirements of the common and original innateness to humans; the innateness that is created by God to all people, Allah says, (So set thou thy face steadily and truly to the Faith: [establish] Allah's handiwork according to the pattern on which He has made mankind: no change [let there be] in the work [wrought] by Allah: that is the standard Religion: but most among mankind understand not) (1). Islam as a natural religion has ordered the Muslims to wear decently, Allah says, ( O Children of Adam!
The study includes the relationship between the ecologia and Abbaside's community in the middle ages, and the role of Baghdad capital city to increasing the sensibility of the people to the outwardly peripheral.
The study explains the efforts between the people and Abbaside's government to cure the knowledge of ecologia, to prevent the separation of diseases and pollutions of the community.
Keywords: Ecologia, Abbasid's, diseases, pollutions.
Reading and analyzing Paula Vogel’s plays, the readers can attest that she achieves success in drama or theater because she is passionate about theater. Vogel is a modern American playwright who won the 1998 Pulitzer Prize for drama. Her success and insight in playwriting or in adapting do not come all of a sudden; she is influenced by many writers. Vogel is influenced by many American dramatists, including Eugene O’ Neill, Arthur Miller, Tennessee Williams, and Edward Albee, and by other non-American writers, including August Strindberg, Anton Chekhove, and Bertolt Brecht. Certainly, there were female playwrights who wrote preeminent plays and they influence Vogel as well. Nevertheless, dramas by female
... Show MoreThe most honorable of science was what was related to the book of God, the Almighty, the Constitution of this nation and the way of its guidance and method of advancement there is no life except for him and safety only by its application and it is no secret to the competent studies of the importance of the subjective studies in the Koranic studies to address issues of great importance enlighten the path of the nation and revive From here comes the importance of the topic covered by the research, which is "Intent in the Holy Quran meanings and semantics", and this topic features features that made it worthy of writing, including the importance of clarifying theories of Qur'anic character of a systematic nature, such as the theory of inten
... Show MoreT.V photo in modern shows has emerged with special characteristics and signs that have developed in cope with the development of medium and technique. This leads to adding a variety of aesthetic dimensions which are capable of attracting audience because of its communicative elements that have an important role in increasing of T.V show Watching. As a result, the research is limited to methodological Framework as the problem. The problem of the research deals with emerging the aesthetic dimensions of T.V photo. The major question is (what are the aesthetic and communicative dimension of T.V Photo?). The research aims at finding out the aesthetic dimensions of T.V photo in modern artworks. The significance of the research on the presented
... Show MoreA Spectroscopic study has been focused in this article to study one of the main types of active galaxies which are quasars, and to be more precise this research focuses on studying the correlation between the main engine of Quasi-Stellar Objects (QSO), the central black hole mass (SMBH) and other physical properties (e.g. the star formation rate (SFR)). Twelve objects have been randomly selected for “The Half Million Quasars (HMQ) Catalogue” published in 2015 and the data collected from Salon Digital Sky survey (SDSS) Dr. 16. The redshift range of these galaxies were between (0.05 – 0.17). The results show a clear linear proportionality between the SMBH and the SFR, as well as direct proportional between the luminosit
... Show MoreAdopting a policy of attracting investments in all countries, whether developing or developed prevailed, especially after the global crisis, and this trend is imposed by considerations of political and development (urban, economic, and social) can be formulated as a rational policy to solve many problems related to patterns of urban growth, economic, social, and including the problem of housing. As the reality of the housing sector in Iraq will require the allocation of substantial resources to promote it by the research problem is the lack of financial resources and the inability of investments to meet the various requirements including the requirements of economic sectors, particularly in the field of housing, infrastructure an
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