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.
Products’ quality inspection is an important stage in every production route, in which the quality of the produced goods is estimated and compared with the desired specifications. With traditional inspection, the process rely on manual methods that generates various costs and large time consumption. On the contrary, today’s inspection systems that use modern techniques like computer vision, are more accurate and efficient. However, the amount of work needed to build a computer vision system based on classic techniques is relatively large, due to the issue of manually selecting and extracting features from digital images, which also produces labor costs for the system engineers.
 
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A hand gesture recognition system provides a robust and innovative solution to nonverbal communication through human–computer interaction. Deep learning models have excellent potential for usage in recognition applications. To overcome related issues, most previous studies have proposed new model architectures or have fine-tuned pre-trained models. Furthermore, these studies relied on one standard dataset for both training and testing. Thus, the accuracy of these studies is reasonable. Unlike these works, the current study investigates two deep learning models with intermediate layers to recognize static hand gesture images. Both models were tested on different datasets, adjusted to suit the dataset, and then trained under different m
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مشكلة البحث:
يبقى الفن ولا زال في جميع حالات التعاقب البشري ومراحل التطور الانساني الاكثر انطلاقة وتميزاً في التعبير عن واقع الانسان وعن مشاعره وانفعالاته وافكاره ذات الصلة بتأثيرات البيئة المحيطة به.
والفن ولاسيما (الرسم) يمثل وسيلة من وسائل التعبير الفني بل يكاد يكون الرسم وسيلة الانسان الاولى التي عبر فيها بخطوط مرئية عن مجالات حياته وعلاقته بالبيئة التي عاش فيها، ويقينا
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المنزل هو الشغل الشاغل لكل انسان لانه المكان الذي يجد فيه راحته ويعبر عن ذوقه ويعكس شخصيته وهو بمن فيه يشكل وحدة عمل وانتاج يتطور بمرور الزمن .
من خلال ملاحظة الباحثة لكثير من النساء في مدينة المكلا انهن يقعن في اخطاء مختلفة عند تأثيث منازلهن بسبب جهلهن اساليب التخطيط السليم لشراء الاثاث او تنسيقه في فراغات المنزل المختلفة . ولكي تصل الباحثة الى هدف البحث كان لا
... Show MoreIn multivariate survival analysis, estimating the multivariate distribution functions and then measuring the association between survival times are of great interest. Copula functions, such as Archimedean Copulas, are commonly used to estimate the unknown bivariate distributions based on known marginal functions. In this paper the feasibility of using the idea of local dependence to identify the most efficient copula model, which is used to construct a bivariate Weibull distribution for bivariate Survival times, among some Archimedean copulas is explored. Furthermore, to evaluate the efficiency of the proposed procedure, a simulation study is implemented. It is shown that this approach is useful for practical situations and applicable fo
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ان الهدف من البحث الحالي هو تقويم كتاب الفيزياء للصف الرابع العلمي وفق معايير تصميم وانتاج الانفوجرافيك ومن اجل تحقيق هذا الهدف تم اختيار المنهج الوصفي(تحليل المحتوى) وحدد مجتمع البحث بكتاب الفيزياء للمرحلة الاعدادية الرابع العلمي, المقررة للعام الدراسي 2020-2019 ـ اما عينة البحث فكانت جميع الرسوم والاشكال والمخططات المتضمنة في هذا الكتاب. تم اعداد اداة التحليل المتمثلة بقائمة معايير تصميم وانتاج الانفوجرافيك
... Show Moreيحتل النفط مكانة هامة وجوهرية ضمن اقتصاديات العالم، حيث إنه يمثل سلعة استراتيجية عالمية ومادة أولية أساسية في الصناعات الكيميائية والبتروكيميائية، كما أنه متعدد الاستعمالات، سواء في الصناعة أو الزراعة، بالإضافة إلى استعمالاته في الحياة اليومية للإنسان، مما جعله ذا مكانة مهمة ضمن أطر التجارة الدولية وموقع خاص في تشكيل الخريطة الاقتصادية للعالم. وقد جاء هذا البحث ليسلط الضوء على استراتيجيات منظمة الأوبك لض
... Show MoreThe Indian costus plasma properties are investigated including electron temperature (Te), "electron density (ne)", "plasma frequency (fp)", " Debye sphere length", and amount of Debye(Nd), using the spectrum of optical emission technique. There are several energies used, with ranging from 300 to 600 mJ. The Boltzmann Plot is used to calculate the temperature; where as Stark's Line Broadening is used to calculate the electron density. The Indian costus was spectroscopically examined in the air with the laser at 10 cm away from the target and the optical fiber at 0.5 cm away. The results were obtained for an electron temperature range of (1.8-2.2) electron volts (ev) and a wavelength range of (300-600) nm. The XRF analysis reveals th
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ملخص البحث بالعربي
عنوان البحث : أجـــــوبة الحافظ محمد البرزالي على سؤالات العز ابن الحاجب في الجرح والتعديل
يهدف البحث : إلى جمع أجوبة الحافظ أبي عبدالله محمد البرزالي في الجرح والتعديل، ودراستها.
يتكون البحث من : مقدمة، وتمهيد، نص السؤالات، وخاتمة، وفهارس.
المقدمة : تسمية الموضوع، وسبب اختياره، وأهميته .
والتميهد : ترجمة مختصرة للحافظ أبي عبدالله البرزالي، والتعريف بأجوبة الحافظ الب
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Disease diagnosis with computer-aided methods has been extensively studied and applied in diagnosing and monitoring of several chronic diseases. Early detection and risk assessment of breast diseases based on clinical data is helpful for doctors to make early diagnosis and monitor the disease progression. The purpose of this study is to exploit the Convolutional Neural Network (CNN) in discriminating breast MRI scans into pathological and healthy. In this study, a fully automated and efficient deep features extraction algorithm that exploits the spatial information obtained from both T2W-TSE and STIR MRI sequences to discriminate between pathological and healthy breast MRI scans. The breast MRI scans are preprocessed prior to the feature
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