A numerical investigation is adopted for two dimensional thermal analysis of rocket thrust chamber wall (RL10), employing finite difference model with iterative scheme (implemented under relaxation factor of 0.9 for convergence) to compute temperature distribution within thrust chamber wall (which is composed of Nickel and Copper layers). The analysis is conducted for different boundary conditions: only convection boundary conditions then combined radiation, convection boundary conditions also for different aspect ratio (AR) of cooling channel. The results show that Utilizing cooling channels of high aspect ratio leads to decrease in temperature variation across thrust chamber wall, while no effects on heat transferred to the coolant is indicated. The radiation has a considerable effect on the computed wall temperature values.
Research includes three axes, the first is the average estimate time of achievement (day) to work oversight, to five supervisory departments in the Office of Financial Supervision Federal and then choose the three control outputs and at the level of each of the five departments above, and after analyzing the data statistically back to us that the distribution of the times of achievement It is the exponential distribution (Exponential Distribution) a parameter (q), and the distribution of normal (Normal Distribution) with two parameters (μ, σ2), and introduced four methods of parameter estimation (q) as well as four modalities parameter to estimate (
... Show MoreObjecte The study aims to test the effect of using the appropriate quantitative method of demand forecasting in improving the performance of supply chain of the aviation fuel product ( The study sample), One of the products of the Doura refinery (The study site), By testing a set of quantitative methods of demand forecasting using forecasting error measurements, and choosing the least faulty, most accurate and reliable method and adept it in the building chain.
Is the study of problem through a starting with the fol
... Show MoreBackground: This in vitro study compares a self-etch primer (SEP) to an etch-and-rinse (EaR) for bonding sapphire brackets by evaluation of the enamel etch-pattern, shear bond strength, amount of remnant adhesive and enamel surface damage following thermal and fatigue cyclic loading. Material and Methods: Ceramic (sapphire) brackets were bonded to 80 extracted human premolars using two enamel etching protocols: conventional EaR using 37% phosphoric acid (PA) gel (control), and a SEP (Transbond Plus). Each group was subdivided into two subgroups (n=20 teeth) according to the time of bracket debonding: after 24 h water storage or following 5000 thermo-cycles plus 5000 cycles fatigue loading, to determine the shear bond strength (SBS), adhesiv
... Show MoreThe main idea of this research is that the researcher believes that media research remains useless unless its goals and results are achieved by using the correct scientific tools. The researcher chooses 100 research papers of about 35% of the published ones, 10 of them are excluded because they are outside media. We use a simple and randomized sample including the three departments of media: journalism, television and radio journalism and public relations. The researcher adopts statistical methods such as Fay coefficient, correlation coefficient, Pearson correlation coefficient and straight line equation.
The researcher uses an analytical form followed by analysis of content, them the scale. The results are found in 58 researches, w
The study included the collection of samples of raw cow milk to isolate Leuconostoc bacteria, samples were sub cultured on De-Man Rogosa Sharpe-Vancomycin medium, the pure colonies were selected and subjected to the cultural and microscopically tests, according to that 25 cocci bacterial isolates were obtained, then isolates were subjected to biochemical tests. Result of tests showed that 12 isolates belong to the genus Leuconostoc out of 25 cocci bacterial isolates, Vitek2 system was used as a supplementary step. Results of final identification showed that 3 sub species were obtained included Leuconostoc mesenteroides ssp. cremoris 9 out of 12 isolates, while it was 2 isolates of Leuconostoc mesenteroides ssp. mesenteroides and one isol
... Show MoreIn this study, ultraviolet (UV), ozone techniques with hydrogen peroxide oxidant were used to treat the wastewater which is produced from South Baghdad Power Station using lab-scale system. From UV-H2O2 experiments, it was shown that the optimum exposure time was 80 min. At this time, the highest removal percentages of oil, COD, and TOC were 84.69 %, 56.33 % and 50 % respectively. Effect of pH on the contaminants removing was studied in the range of (2-12). The best oil, COD, and TOC removal percentages (69.38 %, 70 % and 52 %) using H2O2/UV were at pH=12. H2O2/ozone experiments exhibited better performance compared to
... Show MoreService companies always working to increase their competitiveness and efficiency of the survival, growth and development in the present and the future, including insurance companies, so as to increase competition, especially after the emergence of the civil companies dramatically after 2003, has become the goal of recent studies carried out by the organizations is the human capital, because its success and excellence and achievement its objectives depends on the human, and this does not mean that the other components are not important, but also rely on the rights which has increased interest in the search for the way in which they can guide the behaviors and values and their own language in line with the organization's strategy an
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This research addresses: Sharh Usul Al-Bazdawi "Explanation of the Fundamentals for Al-Bazdawi", by studying and investigating, from the beginning of prohibition chapter to its end. The researcher conducted a study about this book stating its significance and introducing the compiler and the commentator. The researcher as well mentioned that the prohibition has a special formula and requires repetition, and he went on explaining that prohibition according to Hanafis does not require absolute corruption of the prohibited matter unless based on an evidence, and that what is condemned as wrong act for itself is considered void and what is condemned as wrong act for external reasons is considered corrupt accor
... Show MoreObjective(s): To evaluate primary health care services at primary health care centers in Baghdad City and to compare between these primary health care centers relative to such quality. Methodology: A descriptive design, using the evaluation approach, is study to Evaluation of quality of primary care services at primary health care centers in Baghdad City. A multistage probability sample of (36) health care centers was selected. The sample consists of (12) model centers, (12) urban centers, and (12) rural centers.A constructedquestionnaire is composed of (23) items. It consisted of (5) parts that include inta
The research focuses on determining the role of customer relationship management in improving financial performance by surveying the opinions of a number of employees of a number of Iraqi private banks. The customer has become the focus of attention and the most important factors of success and profitability and competition. Therefore, decisions related to the customer are important decisions that support the process of making, And follow-up of administrative decisions, including financial decisions aimed at improving the financial performance of banks and distinguish them from competitors. Thus, the techniques used in customer relations management programs to collect, analyze and use data and information have beco
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