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.
في هذا البحث، تم استكشاف تأثير نوع المكاسب على التفاعلات التعاونية الدولية لاسيما في مجال مواجهة التحديات المناخية. إذ تبين أن المكاسب النسبية تلعب دورا حاسما في توجيه سلوك الدول فيما يتعلق بالاتفاقيات البيئية الدولية. ويعكس هذا التحليل دروسا مهمة لصياغة السياسات والجهود الدولية في هذا المجال ذاته. ان الدول عندما تتوقع مكاسب نسبية تفوق الخسائر المتوقعة من التعاون، فإنها تكون أكثر عرضة للالتزام بالاتفاقيات
... Show MorePerformance measures are a central component of management control system, making good planning and control decisions requires information about how different subunits of organizations have performed. To be effective, performance measures (both financial and nonfinancial) must also motivate managers and employees at all levels of organization to strive to achieve organization goals.
To give aclear picture about performance must be used compound measure, that was best than single measure.
Altman model can be used as a compound performance measure that measures the performance by tied a sum of variables, due to make weight for every variable to reach for performance.
اِنطلقت فِكرة إعداد هذه الدِّراسة بعد الاِطِّلاع على محاضر مجلس الأُمَّة التركي الكبير، ومعرِفة التشريعات التي تناولت مفاصل الحياة الاِجتماعيَّة في تُـركيا، وبيَّنت هذه التشريعات التي نظَّمت مُستوى العلاقة بين المواطن والدولة، وأسهمت في وضع حلول مُـشكِلاتٍ اِجتماعيَّة عديدة منها؛ ما له صِلة بإجراءات الدولة في رفع المظلوميَّة عن المواطنين الأتراك والمقيمون فيها، مع تشخص بعض الظواهر الاِجتماعيَّة السِّـ
... Show MoreThis research deals with a jurisprudential manuscript with study and investigation by Sheikh Ibrahim Al-Kurani, one of the prominent Kurdish scholars in the eleventh century. Some claim that it is heresy in the religion, and that the Prophet, may God bless him and grant him peace, did not do it.
The Sheikh responded to that, confirming its permissibility, and that it does not fall within the innovated matters, based on its permissibility on the two Eids and other religious occasions, and also that the issue of supplication with acceptance was legislated for the sake of worship without specifying it to one without the other, and it is known that prayer is one of the greatest acts of worship. supplication that fasting is accepted;
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ﺣﻘﻮق اﻻﻧﺴﺎن ﺣﻘﻮق ﻣﺮﺗﺒﻄﺔ ﺑﺤﺮﯾﺔ وﻛﺮاﻣﺔ اﻻﻧﺴﺎن واﻟﺘﻲ ﺗﻀﻤﻨﮭﺎ اﻟﺴﻠﻄﺎت اﻟﻌﺎﻣﺔ وﺟﺎءت اﻟﻤﻮاﺛﯿﻖ اﻟﺪوﻟﯿﺔ واﻻﻗﻠﯿﻤﯿﺔ واﻟﺪﺳﺎﺗﯿﺮ ﻟﻠﺘﺄﻛﯿﺪ ﻋﻠﻰ اھﻤﯿﺔ ھﺬا اﻟﻤﻮﺿﻮع وﺑﻘﺪر ﺗﻌﻠﻖ اﻟﻤﻮﺿﻮع ﻓﻲ اﻟﻤﺮأة اﻟﻌﺮﺑﯿﺔ ﻋﺎﻣﺔ اﻟﻌﺮاﻗﯿﺔ ﺑﺸﻜﻞ ﺧﺎص، ان ﺣﻘﻮﻗﮭﺎ ﺗﺸﮭﺪ ﺗﻘﺪﻣﺎً ﻣﻠﺤﻮﻇﺎً ﻓﻲ اﻟﺴﻨﻮات اﻻﺧﯿﺮة ﻧﺘﯿﺠﺔ ﺛﻮرات اﻟﻮﻋﻲ اﻟﺤﺎﺻﻠﺔ ﻓﻲ اﻟﻮﻃﻦ اﻟﻌﺮﺑﻲ، اذ ﺷ
... Show MoreAddresses research philosophy decade in significance vehicle metamorphic between the time the real is between two moments two different: the moment the last beautiful memories of parents and beloved, but the present moment harsh stand on
Hall effect measurements have been made on a-As2Te3 thin films different thickness film in the range (200-350) nm. The Hall mobility in a-As2Te3 thin films decreases with increasing annealing temperature but the carrier concentration increases. When increasing the film thickness increases the Hall mobility decreases, while the carrier concentration increases.
Background: Hyperthyroidism refers to overactive of thyroid gland leading to excessive synthesis of thyroid hormones and accelerated metabolism in the peripheral tissue. Objective: The aim of this study is to evaluate a new member of the IL-1 super family of cytokines interleukin-33(IL-33) levels in serum .in order to evaluate its utility as clinical bio marker of autoimmune disease (i.e. hyperthyroidism) Methods: The present study was conducted on 30 patients from the Iraqi female patients with hyperthyroidism attending Baghdad teaching hospital, in addition to 30 healthy controls. All subjects were (35-65) years old. Parameters measured in the sera of patients and healthy groups, were interleukin -33 (IL-33), Thyroxin (T4), Thyroxin (T3)
... Show MoreThe present study has been carried out to estimate heavy metals mobility, bioconcentration and transfer from polluted soil to roots tissues and from roots tissues to aerial parts using bioconcentration factor and translocation factor. Soil samples and the biomass of the eight vegetable species have been collected during summer season, 2019 from four different sites in Wadi Al-Arg, Taif Governorate, KSA. In general, heavy metals content of soil samples in site III and IV have recorded elevated values compared with those of site I and II. The soil from site IV has shown the highest concentration of Mn, Ni, Cr, Pb, Cu, and Cd amounted 31.63, 14.05, 13.56, 22.79, 31.02 and 2.98 mg/kg dry soil respectively, while the soil from site III has sh
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