المقدمة (Introduction) عند سقوط الضوء على الحد الفاصل بين وسطين مختلفين بالكثافة البصرية فان جزء من هذا الضوء ينعكس والجزء الأخر ينكسر والجزء الأخير يمتص ، معتمدا على نوع الوسطين وطبيعة السطح الفاصل بينهما . في هذا الفصل سوف نتحدث على الانعكاس والانكسار لكونه يحدث للجزء الاكبر من الضوء بالنسبة للمواد العازلة الشفافة ، ويهمل الامتصاص لكونه قليل النسبة في هذه المواد ، بينما تزيد نسبة الضوء الممتص في المعادن التي ليست

A numerical simulation is made on the thermal lensing effect in an laser diode end-pumped Nd:YAG laser rod. Based on finite element method (FEM), the laser rod temperature distribution is calculated and the focal length is deduced for a Gaussian and super-Gaussian pump beam profiles.

At the pump power of 20W, the highest temperature located at the center of end-pumped face was 345K, and the thermal lens focal length was 81.4mm along the x-z axis. 

The results indicate that the thermal lensing effect sensitively depend on the pump power, waist radius of the pump beam and the pump distribution in a laser rod geometry.

This study aimed at identity baying the difficulties which face public basic school
principals in jar ash governorate in editing formal letters and correspondence and means of
debating with these problems to collect data the researchers developed a question air were
established the population of the study which represents its sample consisted of 129 principals
65 males and 64 females
The results of the study revealed that the principals face difficulties in office and file
management in preparing plans and reports and writing formal letters and answering them
saved recommendations were presented among which were organizing training sessions and
workshops to train the principals on how to dead with there problems.<

The present study intends to trace The friendship in puple and the differences in this according to the variables of age and sex .
The study sample includes (200) puple in intermediate, and secondary schools in Baghdad in AL- Karkh .The sample is the age of whom is ranging from (13) to (15) years .
Maghly scale for measuring the development of friendship is adopted in this study after adjusting it to the Iraqi environment . The Scale consists of (40) items .
The face and construct validity of the Scale is checked as well as its reliability which is checked by test- retest
The study reveals the following :
1 – There is positive effect of the interaction between the of middle scale friendship .
2 – There is No differe

Education around the world has been negatively affected by the new coronavirus disease (COVID-19) pandemic. Many institutions had to transition to distance learning in compliance with the enforced safety measures. Distance learning might work well for settings with stable internet connections, professional technical teams, and basic implementation of technology in education. In contrast, distance learning faces serious challenges in less fortunate settings with inferior infrastructure. This report aims to shed light on the immediate action steps taken at a leading pharmacy school in Iraq to accommodate for the enforced changes in pharmacy education. The University of Baghdad College of Pharmacy went from less than minimal technology impl

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Educational services in Iraq face many problems that have reduced the efficiency of the educational process, as a result of the difficult conditions experienced by educational services in Iraq. This led to the accumulation of these problems and their exacerbation significantly over the years, as there was no fundamental solution to these problems. The study proposes a planning method for managing the educational system in Iraq, especially for the primary and secondary levels, where these negative phenomena are very prominent, especially the deficit in school buildings and the phenomenon of overcrowding in classrooms. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&am

The aim of this study is to recognize the influence of model of active thinking in achievement ofeighth grade students andtheir visual thinking in science.The finds of this research show the superiority students of the experimental group who studied the science material by using the active thinking model on the students of the control group who studied by usual method, in the achievement test. Also the finds show that the students of the experimental group are more successful than students of control group in the test of visual thinking, so the two null hypotheses have been rejected. In light of the results of the research, numbers of recommendations were made.

The current research attempts to examine the relationship between social-psychological conflict and their relation to family upbringing approaches among the adolescents of intermediate stage according to sex and economical level. To do this, the researcher prepared a questionnaire to measure social-psychological conflict that consisted of (32) item divided on four dimensions, and also she prepared a questionnaire to measure family upbringing approaches which composed of (28) item divided on four dimensions. The sample was (260) male and female student from intermediate stage chosen randomly. The results revealed that there were significant differences between social-psychological conflict which went to male, there was a negative correlat

Libraries were and still are the source of science and knowledge in schools, universities and science houses. Therefore, it is a must to briefly display Libraries’