The purpose of this study is designate quenching and tempering heat treatment by using Taguchi technique to determine optimal factors of heat treatment (austenitizing temperature, percentage of nanoparticles, type of base media, nanoparticles type and soaking time) for increasing hardness, wear rate and impact energy properties of 420 martensitic stainless steel. An (L₁₈) orthogonal array was chosen for the design of experiment. The optimum process parameters were determined by using signal-to-noise ratio (larger is better) criterion for hardness and impact energy while (Smaller is better) criterion was for the wear rate. The importance levels of process parameters that effect on hardness, wear rate and impact energy propertie

It is out of question that USA foreign policy has a great superiority and
influence all over the world.
This study deals with all dimensions; aims; and challenges of the American
foreign policy. It aims to answer the following question: within the current changes in
the world, how can the aims of the American foreign policy be realized?

The study examines the root causes of delays that the project manager is unable to resolve or how the decision-maker can identify the best opportunities to get over these obstacles by considering the project constraints defined as the project triangle (cost, time, and quality) in post-disaster reconstruction projects to review the real challenges to overcome these obstacles. The methodology relied on the exploratory description and qualitative data examined. 43 valid questionnaires were distributed to qualified experienced engineers. A list of 49 factors causes was collected from previous international and local studies. A Relative Important Index (RII) is adapted to determine the level of importance of each sub-criterion in the fou

The research creativity this is to discuss theoretical singled offer literature Multi creativity philosophical and psychological has included chapters on four things: The first chapter discusses the concept of creativity language and idiomatically and complement to achieve a broader understanding of the subject of creativity was addressed to a group orientations psychological theory consider creativity as a mental process or a production process or he set of features.

The second chapter has offered the theoretical frameworks that dealt with creativity and included early views on creativity and interpretations based on the basis of personal and creative interpretations based on the basis o

يعد موضوع العنف من اهم المواضيع التي بحثت لكونه اخطر اشكال التهديد لامن المجتمع الانساني واستقراره .. والملاحظ أن جميع المجتمعات على اختلاف ثقافاتها تعاني من العنف والجريمة واثارها بوجه من الوجوه وبدرجات متفاوتة، فكل مجتمع في هذا العالم الواسع يدفع ثمناً باهظاً لما تسببه من اضرار بشرية ومادية ولما تبذله السلطات من جهود من اجل منع وقوع الجريمة. واذا كان من الصعب تقدير قيمة الضرر المادي للجريمة فانه من ال

To observe the effect of media of the internal pressure on the equivalent stress distribution in the tube, an experimental study is done by constructing a testing rig to apply the hydraulic pressure and three dies are manufactured with different bulging configurations (square, cosine, and conical). In the other part, ANSYS APDL is generated to analyze the bulging process with hydraulic and rubber (natural and industrial) media. It was found that when the media is a rubber, the stress is decreased about 9.068% in case of cosine die and 5.4439% in case of conical die and 2.8544% in case of square die. So, it can be concluded that the internal pressure in the rubber media is much better than in hydraulic media. Also, the force needed for fo

      The research aims at showing the media awareness for Students, especially for the students of the preparatory schools through their following the mass media in forming the cultural, educational and political database. It also aims at building a content and prospectives that make them a wide awake stratum that safeguard the society which has faced huge effects of terrorist actions.

                 Furthermore, it aims at knowing to what extent that students have been acquainted with the printed and electronic newspapers. Finally, it aims at knowing to what extent that they are content with the mass media in covering and

The paper include study the effect thickness of the polymeric sample which is manufactured by thermo press way. The sample was used as an active tunable R6G laser media. The remarks show that, when the thickness of the samples is increased, with the same concentration, the spectrum will shift towards the short wavelength, & the quantum fluorescence yield will increased. The best result we obtained for the quantum fluorescence yield is (0.68) at the sample, with thickness (0.304mm) in Ethanol solvent, while when we used the Pure Water as a solvent, we found that the best quantum fluorescence yield is (0.63) at (0.18mm) thickness of the sample.

The paper include studies the effect of solvent of dye doped in polymeric laser sample which manufactured in primo press way, which is used as an active (R6G) tunable dye lasers. The remarks show that, when the viscosity of the solvent (from Pure Water to Ethanol), for the same concentration and thickness of the performance polymeric sample is increased, the absorption spectrum is shifts towards the long wave length (red shift), & towards short wave length (blue shift) for fluorescence spectrum, also increased the quantum fluorescence yield. The best result we obtained for the quantum fluorescence yield is (0.882) with thickness (0.25mm) in Ethanol solvent in concentration (2*10-3mole/liter), while when we used the Pure Water as a solvent,

The study aims to build a proposed training program for school leaders in the Sultanate of Oman on the planning practices of the Kaufman model in light of the needs and challenges of reality. It also aims to identify the challenges facing school leaders in practicing the stages of strategic planning. To achieve these objectives, the study adopted the descriptive approach due to its suitability to the nature of the study. A questionnaire was used to collect the needed data. The study sample included (225) individuals from school principals, their assistants and senior teachers in post-basic education in the Sultanate of Oman. After processing the data statistically, the study concluded that the reality of planning practices for school lea