The design, construction and investigation of experimental study of two compound parabolic concentrators (CPCs) with tubular absorber have been presented. The performance of CPCs have been evaluated by using outdoor experimental measurements including the instantaneous thermal efficiency. The two CPCs are tested instantly by holding them on a common structure. Many tests are conducted in the present work by truncating one of them in three different levels. For each truncation the acceptance half angle (θc) was changed. Geometrically, the acceptance half angle for standard CPC is (26o). For the truncation levels for the other CPC 1, 2 and 3 the acceptance half angle were 20o, 26o and 59o, consequently. A significant difference between the instantaneous thermal efficiency of 3.86× CPC (θc=20o) and 2.32× CPC (θc=26o), and between that for 3.61× CPC (θc=26o) and 2.32× CPC (θc=26o). It's noticed that the difference between the instantaneous thermal efficiency of 2.32× CPC (θc=59o) and 2.32× CPC (θc=26o) is small compared with the difference of the first and second cases, the instantaneous thermal efficiency of 2.32× CPC (26o) was higher than those for other three CPCs. The experimental results show that the maximum thermal efficiency of the full 2.32×CPC (26o) is 0.708, the maximum thermal efficiency of the 3.93×CPC (15o), when it's truncated to 3.84× CPC (20o), 3.61× CPC (26o) and 2.32× CPC (59o) are 0.51, 0.52 and 0.66, respectively. As the concentration ratio decreases from (3.93× to 1×), the thermal efficiency, energy losses and optical efficiency increase from (0.47 to 63), (1.58 to 7.2 K.m2/W) and (0.494 to 0.797), respectively.
Among the commentators who contributed greatly to explaining the basic rules of civilizations in general and Islamic civilization in particular, Sheikh Muhammad Rashid Rida in his interpretation called (Interpretation of the Wise Qur’an), known as (Al-Manar); Whoever reads the tafsir will notice that it was concerned with explaining the civilized aspects in terms of foundations, methodology, factors of demolition and destruction, and ways to avoid them.
بينت النظريات والمناهج النقدية الحديثة بعد تفعيلها لوسائل قراءة النص وتحليل عناصره وبيان وسائل تماسكه وروابطه فضلا عن تمثيله لمضامين مركزية ودلالات فرعية ان النصوص التراثية بوصفها نصوصا كاملة لسمات النص المؤثر قابلة للحضور في مجال المعرفة وفق تصور حديث يختلف عن تصور منتجهامنهجيا كما اتضح مدى عمق هذه النظريات والاسس التي ارساها بلاغيو العرب التي كانت ولاتزال محط انظار كبار النقاد وباحثي البلاغة.
Abstract The Kenyan policy towards Somalia was influenced by a set of interrelated factors between the two countries and stemmed from the internal environment and most prominent: the geographical factor, ethnic, cultural, religious, political, economic and security, has been dominated by this policy since independence from the British colonial administration in the sixties of the last century and so far the nature of instability and tension, As the two countries are geographically contiguous and as security risks escalate, Kenya in 2011 rushed military action against Somalia, the first military action by Kenya outside its borders since independence.
اتضح لنا ما تقدم ان ما يسمى بالتنمية البشرية المستدامة لا تعدو تكون غير سياسة لتحشيد واستقطاب القوى المضادة للتقدم وتحويلها الى جيش موغل في منافعه بعد تشريكه بجرائم الامبريالية وتوظيفه ضد شعبه بإسم التنمية، وبإسم قلب لسلم الاولاويات، وتحريف تاريخ التقدم والتطور الذي لم يبني عرشه لا بتقديم الرعاية الانتاجية، الاقتصادية على الرعاية الاجتماعية، طيلة حقبة زمنية تجاوزت الاربعة قرون. ولما كان عصياً قلب ال
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Abstract
This study dealt with " The Strategic analysis of Operating Income". The study Concerned with two main variables, they are: Strategic analysis and operating income and used one of the total strategic analysis tools, it is "resources analysis method" through analysing the change in operating income in the years that taken in comparing in three components: growth, price recovery and productivity.
To achieve the goal of the research, the study depended upon a hypothesis, "The strategic analysis of operating income leads to supply the appropriate information for the management to make sure of executing its definite strategies".
There is agroup o
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The term of ability (Al qoudra) is of the common terms which used by speech scientists to relate to one of the important verbal issues which called “Fate and destiny”. the issues of fate and destiny has been raised by Muslims since the dawn of Islam and It was researched among speech scientists, there are many opinions about this issues as the man can do or leave anything or he forced to do something that mean he hasn’t ability.
Also the term was used by jurists and they mention to the ability conditions (Assigning the Divine) and when this conditions are not available that means the man is not commissioning, the conditions are Mind, puberty and other conditions which mentioned in the books of jurisp
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التنظيم القانوني للمهني – دراسة مقارنة في نطاق الاعمال التجارية
The Holy Koran is the highest text in the eloquence, It is one of the
important sources of the linguistic syntactic and eloquent study; it impacts
upon these sciences Avery intense impact through advancing its verses as an
argument in the confirmation of the significance of the term
The holy Koran was and still the fountain of the linguistic studies, as
they tend towards it since the second century of the hegira. So this research is
a study of the expressive terms concerning the rain in the holly Koran, a
linguistic study; it aims to study the term concerning its linguistic and
conjugate significance and its expression concerning the rain through reality
and metaphor.