In this research, an experimental study was conducted to high light the impact of the exterior shape of a cylindrical body on the forced and free convection heat transfer coefficients when the body is hold in the entrance of an air duct. The impact of changing the body location within the air duct and the air speed are also demonstrated. The cylinders were manufactured with circular, triangular and square sections of copper for its high thermal conductivity with appropriate dimensions, while maintaining the surface area of all shapes to be the same. Each cylinder was heated to a certain temperature and put inside the duct at certain locations. The temperature of the cylinder was then monitored. The heat transfer coefficient were then calculated for forced convection for several Reynolds number (4555-18222).The study covered free convection impact for values of Rayleigh number ranging between (1069-3321). Imperical relationships were obtained for all cases of forced and free convection and compared with equations of circular cylindrical shapes found in literature. These imperical equations were found to be in good comparison with that of other sources.
Abstract
The aim of this study was to identify the impact of the Knowledge Management Processes on organizational creativity in the Airlines Companies working in Sudan. The hypotheses formulated as:, there is a positive relationship statistically significant differences between knowledge management processes (diagnosis, the acquisition, storage, distribution and application) and organizational creativity. the measurement of the variables had been adopted from previous studies. The study used a Descriptive approach and and the analytical statistical method to construct the model and SPSS Program for data analysis .Purposive sample procedure had been chosen and structured questionnaire had been developed. Out of 215 q
... Show MoreThis research aims to analyze the impact of the United States policy of pressure and sanctions on changing Iran's conduct. Since the Islamic Revolution of Iran in 1979, the US has continuously pursued various policies towards Iran, aiming to change the regime by force or isolate it politically and economically. The main research question lies in the following: To what extent does the US pressure policy and its sanctions affect the conduct Iran?. This research discusses that the more there are economic and political alternatives to Iran, the more it will be challenging the US demands. Moreover, the more the US pursues a negotiating policy based on mutual interests, the more Iran will positively respond to American demands.
Financial markets play an important role in the economy, as it contributes to the financial and economic system of the state stability, as it reduces the adoption of the companies on the loans granted by the banks, as financial markets contribute to attracting and channeling savings to small savers who will be able to buy a number of shares proportional to their savings, It also provides them the place of exchange, and play technology and information systems an important role in facilitating exchanges and increased market activity, in this research touched on the importance of information technology in effect on the activity of the financial markets. Research is divided into three demands of the first concept of eating and the importance
... Show MoreThis research aims to identify and measure the role of TQM in the process of developing the financial performance of Diyala State Company and show the reality and obstacles, after applying the company's management to the requirements of ISO 9001: 2008 and compare it with its performance before applying this standard, The researcher measured the financial performance by conducting financial analysis of the financial statements and conducting a number of interviews at the company's headquarters, Diyala State Company (one of the Iraqi Ministry of Industry and Minerals formations) was sele
... Show MoreThe tourism industry, with its two sides (recreational and religious), is one of the important investment fields in Iraq, it is represented Iraq as the second economic source after the oil sector. So a need for serious efforts to develop the tourism sector and maintain its sustainability. This paper will be one of the important contributions in this field; the paper aims to explore the extent of the impact of the sustainable strategy on the level of overall performance in the Iraqi tourism sector. The field of research was some Iraqi tourist institutions at Iraqi tourism, Which covers the field of study on the one side, and can be studied on the other side, for the developing study methodology and organizing its main parts, the research pap
... Show MoreThis 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 problem of research was the lack of research that dealt with issue of the job design approach that is more suitable for knowledge work, therefore, the research aims to determine the impact of job enrichment, and knowledge capitalon strategic success, starting from the hypothesis that there significant impact of job enrichment and knowledge capital on strategic success, to achieve this goal the researchers from the theoretical literature and related studies conclude to the construction of the scheme shows the hypothetical relationship between the variables, which was adopted job enrichment as independent variable while knowledge capital plays two roles, the first as an independent variable and the second as an intermediate
... Show MoreEducation represents a different their areas, especially after the educational cornerstone of Staff of the community in which young person’s that can stand up and shared the overall development process.
In order for education to be effective in the community, there is a need to develop to cope with the process development of civilization and modern technology. And for that to be achieved the goal of current research to stand on the advancement of the educational process through Knowledge of educational strategies that had previously requirements put forward for the development of educational process as well as through Knowledge of the mo
... Show MoreThe structural, optical properties of cupper indium gallium selenite (CuIn1-xGaxSe) have been studied. CuIn1-xGaxSe thin films for x=0.6 have been prepared by thermal evaporation technique, of 2000±20 nm thickness, with rate of deposition 2±0.1 nm/sec, on glass substrate at room temperature. Heat treatment has been carried out in the range (373-773) K for 1 hour. It demonstrated from the XRD method that all the as-deposited and annealed films have polycrystalline structure of multiphase. The optical measurement of the CIGS thin films conformed that they have, direct allowed energy gap equal to 1.7 eV. The values of some important optical parameters of the studied films such as (absorption coefficient, refractive index, extinction coeffici
... Show MoreBackground: Polishing technique for acrylic resin material have great effect on properties of acrylic material and bacterial colonization such as staphylococcus aurous, which are responsible for many acrylic prosthetic infections such as the commonly ocular infections. Ineffective polishing technique could affect roughness and subsequently porosity of acrylic materials.So, a new effective method for polishing acrylic was used depending on the use of optiglaze coating material. So, this study aimed to evaluate the effect of optiglaze polishing on porosity of acrylic resin material and staphylococcus aurous activity in comparison to conventional polishing technique.
Materials and methods: Specimen(n=120) were prepared :20 spe
... Show More