The hydraulic behavior of the flow can be changed by using large-scale geometric roughness elements in open channels. This change can help in controlling erosions and sedimentations along the mainstream of the channel. Roughness elements can be large stone or concrete blocks placed at the channel's bed to impose more resistance in the bed. The geometry of the roughness elements, numbers used, and configuration are parameters that can affect the flow's hydraulic characteristics. In this paper, velocity distribution along the flume was theoretically investigated using a series of tests of T-shape roughness elements, fixed height, arranged in three different configurations, differ in the number of lines of roughness element. These elements were used to find the best configuration of roughness elements that can be applied to change the flow's hydraulic characteristics. ANSYS Parametric Design Language, APDL, and Computational Fluid Dynamics, CFD, was used to simulate the flow in an open channel with roughness elements. CFD can be used to study the hydrodynamics of open channels under different conditions with inclusive details rather than relying on the costly field and time-consuming. Runs were implemented with different conditions, the discharge, and water depth in upstream and downstream of the flume. T-shape roughness elements with height equal to 3cm placed in three different configurations, two lines, four lines, and fully rough configurations were tested. The results show that the effect of roughness elements increasing with increasing the number of lines of roughness elements. Cases of four lines and fully rough configurations have almost the same hydraulic performance by having the same results of the velocity decrease percentage, which is decreased by approximately about 66% and 61% of the control case's velocity in the zone near the roughness elements consequently. But the difference is that four lines configuration is affected in a part of the test section. This behavior increases the velocity values by about 11% in the other side and by about 10% near the free surface in the case of four lines configuration and increased by about 32% above the roughness elements in a fully rough configuration.
The study aimed to reveal the obstacles of administrative creativity among the leaders of secondary schools (the curriculum system) in the northern border region, which relate to the obstacles (organizational, motivational, and psychological). In addition, to identify the most important statistical differences between the responses of the members of the study sample, which attribute to the variables (educational qualification, year’s Administrative expertise). To achieve the goal of the study, the researcher used the descriptive analytical approach, and to verify the validity of the tool, it has presented to several referees and faculty members in the educational field. The validity of the internal consistency was also calculated for t
... Show MoreTonsillitis is an infection or inflammation of the tonsils. Tonsillitis classified as acute, chronic (recurrent) and complication. Most often it is caused by a virus, but it may also be caused by the same bacteria that cause strep throat. According to numbers that data shows, the virus is more common, about 77.49% than bacterial which about 71.45% then fungal about 9.6%. The principal symptom of tonsillitis is a sore throat fever, swollen lymph nodes, nasal congestion, difficulty in swallowing and headache may also occur, according to if symptoms of tonsillitis are known or not, data show that they know about (119 of people) (79.3) this result is greater than unknown which was about 31 (20.7).
In recent years, the attention of researchers has increased of semi-parametric regression models, because it is possible to integrate the parametric and non-parametric regression models in one and then form a regression model has the potential to deal with the cruse of dimensionality in non-parametric models that occurs through the increasing of explanatory variables. Involved in the analysis and then decreasing the accuracy of the estimation. As well as the privilege of this type of model with flexibility in the application field compared to the parametric models which comply with certain conditions such as knowledge of the distribution of errors or the parametric models may
... Show MoreThe research aims to identify the administrative skills and their role in institutional performance, and used the descriptive approach in a survey style and correlational relations to suit the nature of the problem to be studied.The research community was identified with the directors of sports activity in the Iraqi universities in a deliberate manner, and their number is (134) directors, where two scales (administrative skills and institutional performance) were used and the two scales were distributed to the above-mentioned sample in order to obtain answers that meet the required and representative sample of the community on the day 3/12/2021. The answers to all the statements were completed and after processing the results statistically
... Show MoreThe study aimed to explore the school principals’ servant leadership practices for primary teachers’ perspectives in the Sultanate of Oman, furthermore to investigate the differences in those practices attributable to variables (gender, qualification, educational stage, years of experience, governorate). The study relied on the descriptive approach, by employing the survey research design using the questionnaire as a main tool for data collection, which included five dimensions of servant leadership (altruism, humility, enhancing teacher development, emotional healing, commitment to community development), Data collected from (1094) teachers in basic education schools, and they were chosen randomly. The results of the study indicated
... Show MoreThis research deals with the role of quantitative (indirect) tools of monetary policy that used by the Central Bank of Iraq in order to control and manage the size of the money supply that intermediate goal through which monetary policy is able to achieve its final goals, foremost among which is to reduce inflation and raise the value of the local currency in front of foreign currency rates. The research is based on a major hypothesis stating that quantitative tools have a direct and strong influence on the money supply, especially under the circumstances of the shift towards a market economy. There has been a branching relationship with this statistically significant relationship between the money supply and the quantitative tools used
... Show MoreIn order to have an idea about what happens in Iraqi food establishments in relation to implement quality management system ISO 9001, this study was performed to show the actual situation of Iraqi food establishments concerning quality management system (ISO 9001:2015), reasons of implementing, factors that hinder implementing and problems faced high administration for getting establishments certification ISO 9001:2015. The study demonstrated from the questionnaire some difficulties to implement ISO 9001 for both of establishments that implemented the quality system or which in implementing of this international standard. The most important problems during implementing were business culture and costs and the most important proble
... Show Morehe present work, among other previous studies done in our lab, aimed to highlight the histopathological effect of S. xylosus peptidoglycan in comparison to LPS of E. coli. Materials and methods: One hundred and fifty urine specimens were collected from urinary tract infection patients visiting Baghdad hospitals. The histopathological effects of S. xylosus S24 peptidoglycan was studied in the urinary tract of female mice by injecting 5 animal groups at the following concentrations: 1000, 2000, 3000, 4000, and 5000 µg/mL. Another 5 groups were injected with 10, 25, 50, 75, and 100 ng/mL of E. coli (serotype 0128:B12) LPS. Results: Ten isolates were confirmed to be Staphylococcus xylosus. Histopathological study showed different pathological
... Show MoreIRA Dawood, JOURNAL OF SPORT SCIENCES, 2016 - Cited by 3
Helminthiasis is a significant economic burden on grazing cattle. Increased resistance to currently available synthetic anthelmintics used to treat helminthiasis, and anthelmintic residues in meat and dairy products pose a significant worldwide health threat. These obstacles require the development of new anthelmintics capable of combating drug resistance while also exhibiting improved safety profiles. Rhynchosia cana (Fabaceae) is a herb that has historically been used as a worm expeller. To evaluate the phytochemical profile and explore the anti-oxidant and anthelmintic effects of different extracts of Rhynchosia cana (R. cana) by In silico and In vitro methods. Using standardised chemical t
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