A hyperboloid solar concentrator (HSC) was designed with a truncation angle side to the entrance aperture by simulation in the Zemax Optical Design software. The (HSC) has a wide exposure range to solar radiation due to the relatively large entrance aperture. The design consists of an entrance aperture facing the sun to obtain the largest possible amount of solar radiation, and a small exit aperture compared to the entrance aperture whose mission is to receive solar radiation after it enters the entrance aperture and reflects it from the inner reflective walls of the (HSC). In the exit aperture, there is a detector to measure the number of rays incident on it, which is a measure of the optical efficiency of the s
... Show MoreWater is crucial for all known forms of life without providing any calories or organic nutrients, while many people, especially in developing countries, may not be able to access pure and safe drinking water. They could lose their lives or become sick because waterborne diseases could contaminate the water, and when the chemical and/or physical properties of the water are not within the national and international standards. Thus, the present study aimed to evaluate water quality of the Halabja drinking water and Sirwan river. Halabja city is located to north of Iraq, north-east of the capital Baghdad. Every week of the year 2019, apart from official holidays, water samples were collected from each of river and several areas (4-10 section
... Show MoreMost countries in the world particularly developing countries, including Iraq, facing extremely dangerous problem with social and political dimensions, which is the emergence of the food crisis problem ,the decrease in domestic food production in Iraq isn't meet the needs of its population food, due to the fact that the agricultural sector suffers from multiple natural ,economic and human problems .It is still below the level required to meet the needs of the population of food ,since food at the forefront of priorities needed by the human . This represents indispensable basic necessity , so the responsibility of its availability permanently in appropriate&nb
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The research aims to investigate the private sector attitudes toward operational contracting in special education schools. The research adopted the qualitative approach by using personal interviews with a sample of (45) private school owners and managers in Oman. The results of the research revealed that there is an agreement among the majority of respondents on the ability of the private sector to manage special education schools, the advantages of the partnership, as well as the need for guarantees to support this partnership. The government should fully assume it. The role of the private sector remains to raise the operational efficiency of schools. Opinions vary about the level of powers granted to t
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The aim of the research is to develop specific skills of 21 century, one schedule, renewable: (sex, years of experience, academic degree) from the viewpoint of the research sample. The descriptive tool was used to collect information for research purposes. It was applied to a sample of (339) male and female teachers in Al-Ardhah governorate schools to teach Jazan. The application was carried out in the second semester of the year 1442 AH. The research concluded with a set of results, the most important of which are: the approval of the sample members to a large extent on the expressions of the role of school leaders in the practice of developing male and female teachers in acquiring these three skills fr
... Show MoreIn the name of of Allah the Merciful
Introduction:
Praise be to Allah, Lord of the Worlds, and prayers and peace be upon our master Muhammad and his family and companions.
After
I have looked at a part of the jurisprudence of Hajj jurisprudence, which is needed now, especially after it facilitated travel to perform Hajj and Umrah, so the need was an advocate and a list for writing in it, which is beneficial to Hajj, Umrah and the guide.
And this important part is the things that contravene the woman's man in the Hajj and after the search and tracking found that there are ten things that get the violati
... Show MoreReceipt date:2/17/2021 acceptance date:3/16/2021 Publishing date:12/31/2021
This work is licensed under a Creative Commons Attribution 4.0 International License.
Objective: This paper investigates the contradictions in the decision-making process of the United States, which historically proven to be successful policies in the short term, but in the long term proven to be wanting and failure. Methodology: The paper uses descriptive, historical, comparative method. A
... Show MoreThe role of relaxation program for reducing anxiety of patients in dental clinic