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.
This work presents the study of the dark current density and the capacitance for porous silicon prepared by photo-electrochemical etching for n-type silicon with laser power density of 10mw/cm2 and wavelength (650nm) under different anodization time (30,40,50,60) minute. The results obtained from this study shows different chara that different characteristic of porous diffecteristics for the different porous Silicon layers.
The researcher was interested in studying a crucial aspect of the systematic world music culture. He highlights the analysis of the harmonic construction in the musical compositions of the artist Khalil Ismail, where harmony is a significant Western musical science, a pillar of the structure of instrumental and vocal music.
It depends on the compositions of vertical sounds performed simultaneously, as tones coincide and are sometimes dissonant to give sound resonance that enriches musical work and attracts recipients. Hence, the researcher has many questions, including: Can the composition of the writings of the artist Khalil Ismail determine in an objective research framework? Is there a study on this subject in some detail? whic
In this research, we attempt to show the extent of harmony in an aspect of the text according to the stylistics for the Knowing of the stylistic value of the title threshold, and the pathways of titles that suggest and support the meaning when the recipient reads the literary text, in addition to the interpretations that reflect the purposes of the poet who contributed to the drawing of his poetic achievement. The research presented a brief about the poet and his most important works, because they are the text which will be studied according to the stylistics. The research also explained the concept of style and the stylistics in the preface , because of the stylistic is the method adopted by the research to study the title thresholds in
... Show MoreThe current research aims to identify (the effect of CORT program on creative thinking for middle school students in the art education history of ancient art subject).
The research society continue of the5th of scientific students in ALsadreen secondary school of excellence which related of the Directorate of Education al-sader city, for the academic year (2015/2016), The sample was (35) students for each of the two groups (experimental and control). The equivalence between the research groups was carried out in the IQ variable, the age and the level of the father and mother.
The researcher used the experimental method of partial control and the post-test. If the course of
... Show MoreThe research aims to form a clear theoretical philosophy and perceptions about strategic Entrepreneurship through the relationship between high Involvement management practices, the basis in creating that leadership and high-performance work systems as a support tool in achieving them according to the proposals (Hitt et al, 2011), in an attempt to generalize theoretical philosophy and put forward how to apply it within The Iraqi environment, and on this basis the problem of the current research was launched to bridge the knowledge gap between the previous proposals and the possibility of their application, aiming to identify the practices of high Involvement management and the possibility of high-performance work systems and thei
... Show MoreIntroduction and Aim: Diabetes mellitus patients almost always struggle with a metabolic condition known as chronic hyperglycemia. According to the World Health Organization, osteoporosis is a progressive systemic skeletal disorder that is characterized by decreasing bone mass and microstructural breakdown of bone tissue that increases susceptibility to fracture and increased risk of breaking a bone. Here, we aimed to compare the levels of CatK and total oxidative state in patients with diabetes and osteoporosis among the female Iraqi population and study the possible relationship between them. Materials and Methods: This study included 40 females with diabetes (Group G1), 40 with diabetes and osteoporosis (Group G2) and 40 normal healthy f
... Show MoreThe current research dealt with a vital subject contributing In success Iraqi Industrial Companies general and Iraqi Cement state company A market knowledge, It is one of the most important industrial companies that Which serve to fill the local market need Of cement without resorting to import, The problem of research was limited understanding of the importance of the role played market knowledge of the tendencies and desires of competitors, This in turn affects the company's ability to achieve competitive advantages,The research aims to know the extent of adoption Iraqi Cement state company Concept market knowledge And employment achieving Competitive advantage By removing them (Cost, and quality, and del
... Show MoreThe research aims at benefiting from the technological development and the technical progress. This development necessitated that the educational process take advantage of this progress, and the development of special computer software, especially the design programs, made the two researchers think about how to benefit from these design programs in teaching students the skills of theatrical design.
The current search aims at:
Identifying the effect of 3Ds Max in developing the skill of theatrical decoration design among the students of the Department of Art Education "Third stage / Department of Art Education / Faculty of Fine Arts / University of Diyala for the academic year 2014-2015.
The researchers used the ex
... Show MoreThis study included nine patients with inactive carrier states of HBV and 14 healthy control groups. The number and the percentage of T-lymphocyte (CD3+ Cells) in the peripheral blood of these groups showed no significant difference. Similar trend was observed when number and percentages of T helper cells (CD4+ cells) and T cytotoxic lymphocytes (CD8+ cells). Moreover, no significant difference in CD4+ /CD8+ cells ratio (P > 0.05) in peripheral blood of patients with inactive carrier state of HBV as compared with healthy control group. The levels of total serum bilirubin (TSB) concentration and alanine aminotransferase (ALT) activity were similar to control group. The levels of immunoglobulin concentration (IgG and IgM) in patients g
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