In this work an approach has been developed to investigate the influence of surface roughness on thermohydrodynamic performance in aligned and misaligned journal bearings by considering an average flow model and deriving the shear flow factor for various roughness configurations, similar to the pressure flow factor. An average Reynolds equation for rough surfaces is defined in term of pressure and shear flow factors, which can be obtained by numerical flow simulation, though the use of measured or numerically generated rough surfaces. Reynolds, heat conduction and energy equations are solved simultaneously by using a suitable numerical technique (Finite Difference Method) to obtain the pressure and temperature distribution through the oil film thickness of the journal bearing. These equations are obtained for isotropic surfaces and for surfaces with directional patterns. The flow factors for these surfaces are expressed as empirical relations in term of normalized oil film thickness (h/σ) and surface characteristic (γ) defined as the ratio of x and z correlation lengths . The results of this approach showed increase in load carrying capacity and maximum pressure and decrease in maximum temperature in the case of stationary surface roughness (rough bearing and smooth journal) with transverse pattern. The results obtained through this work have been compared with that published by other works and found to be in a good agreement.
The current study aims to investigate the effect of the interaction between the use of the improve strategy in teaching mathematics and the level of academic achievement on the acquisition of algebraic concepts and habits of mind among tenth-grade students in Oman. The study adopted the experimental method, based on a quasi-experimental design with two groups: experimental and control groups and pre-post-measurement. The study sample consisted of (28) 10th-grade students as an experimental group and 26 of 10th-grade students as a control group in Al-Tufail bin Amr School in South Al Batinah. The differences in the pretest and posttest gains were analyzed using mean, standard deviation, ANCOVA, t-test, effect size (eta-square), and two-wa
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The research aims to determine the role of the efficiency of Human Resources Information System in the effectiveness of Employees Performance Appraisal System in the Ministry of Higher Education and Scientific Research / Center for the ministry, it was touching the researchers need the ministry to devise methods that employ outputs Human Resources Information System in the organization surveyed for the development of methods and levels of process evaluate the performance of its employees, in order to identify the extent of the role played by human resources information system in the process of assessing the performance of employees, we raised the question of the President as follows:
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The objective of the research is to shed light on the nature of the impact of the activities of the national strategy for poverty alleviation in achieving the goals of sustainable development, and the research problem was represented by Is there an effect of the activities of the national strategy for poverty reduction in achieving the goals of sustainable development? and represents the field of research in the Ministry of Labor and Social Affairs For the years (2012-2016) and the results of the sustainable development goals indicators for the years (2012-2016), the ready-made statistical program (SPSS ver.10) was used to calculate the percentages, multiple linear regression equation, the F test and the R2 coefficient, and the research
... Show Morecharge transfer complex formed by interaction between the p- aminodiphenylamine (PADPA) as electron donor with iodine as electron acceptor in ethanol at 250C as evidenced by color change and absorption. The spectrum obtained from complex PADPA – Iodine shows absorptions bands at 586 nm. All the variables which affected on the stability of complex were studies such as temperature, pH, time and concentration of acceptor. The linearity of the method was observed within a concentration rang (10–165) mg.L-1 and with a correlation coefficient (0.9996), while the molar absorbitivity and sandell sensitivity were (4643.32) L.mol-1.cm-1 and (0.0943) μg.cm-2, respectively. The adsorption of complex PADPA–I2 was studied using adsorbent surfaces
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The Video Assistant Referee (VAR) is a technology designed to review on- eld decisions through video footage in order to correct clear and critical refereeing errors. It enables the replay of key moments in slow motion to determine the correct naldecision,withcommunicationbetweenthevideoof cialsandtherefereeconductedviaheadset.Thesystem operates under the principle of "minimal interference, maximum bene t," intervening only in essential situations. This study aimedtoassessthecurrent implementationofVARintheIraqStarsFootballLeagueduringthe2023–2024season. To achieve this objective, the researchers employed a descriptive survey method involving a sample of 220 participants, including referees, coaches, players, assessors, academics, a
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The current research aims to demonstrate the relationship of correlation and influence between the independent variable strategic control through its dimensions represented by (organizational structure, human resources management, commitment to specialization, defining powers and responsibilities, values and integrity) and the dependent variable the performance of the insurance company, and the degree of arrangement of these dimensions according to their importance, as well as Detection of significant differences in the sample's response to the questionnaire paragraphs in the researched company, and the research problem
... Show MoreThis study was carried out at the Poultry Research Station belong to state Board of Agricultural Research, Ministry of Agriculture, Abu Ghraib. The duration of this study was from 28 November 2013 to 15 May 2014 to evaluate the effect of supplementation different levels of organic selenium(Se-yeast) and inorganic selenium (Selenium selenite) on some productive performances of broiler breeder and selenium levels in plasma ,egg (yolk,albumin). The study included 336 female broiler breeder and 28 males (Ross 308 and arbor acres), 42 weeks old were randomly distributed to 7 dietary treatments experiment with 2 replicates / treatment (24 females and 2 male birds /replicate). The duration of the experiment was 24 weeks, and treatments were as the
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Abstract
The goal of current research to describe and diagnose the level of attention of doctors to design and regulatory dimensions, (strategic vision, organizational structure, organizational processes, business systems, personnel), and the performance of hospitals and dimensions, in six hospitals in medicine and selected a sample for research, as well as identify organizational design effect in the performance of hospitals and dimensions (efficiency, the development of human resources, patient satisfaction, achieve financial results, quality of health care).
Research has focused in part theoretical on key variables to look organizational des
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A field experiment is conducted to study the effect of different levels of peat (0, 25, 50, 75, and 100 Mg ha-1 to uncropped and cropped soil to wheat. Soil samples are taken in different period of time (0, 3, 30, 60, 90, 120, and 180 days after cultivation to determine (NaHCO3-Exteractable P at 3 different depths (0-10, 10-20, and 20-30 cm). Field Experiment is conducted in a randomized complete block design (RCBD) with four replicates. Wheat, Al-Rasheed variety, is cultivated as a testing crop. The entire field is equally dived in two divisions. One of the two divisions is cultivated to wheat and the second is left uncropped. The effect of five levels of peat namely 0, 25, 50, 75, 100 Mg ha-1 is investigated. Soils are fully analyzed
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