The two-dimensional transient heat conduction through a thermal insulation of temperature dependent thermal properties is investigated numerically using the FVM. It is assumed that this insulating material is initially at a uniform temperature. Then, it is suddenly subjected at its inner surface with a step change in temperature and subjected at its outer surface with a natural convection boundary condition associated with a periodic change in ambient temperature and heat flux of solar radiation. Two thermal insulation materials were selected. The fully implicit time scheme is selected to represent the time discretization. The arithmetic mean thermal conductivity is chosen to be the value of the approximated thermal conductivity at the interface between adjacent control volumes. A temperature dependent specific heat capacity proposed by a 4th Degree polynomial is fitted. A good agreement is obtained when the predicted results are compared with those obtained from the analytical solution.
إن التغيرات السريعة والبعيدة المدى في تكنولوجيا المعلومات القائمة على أساس الالكترونيات الدقيقة تساعد في حدوث تحول في صورة الاقتصاد العالمي، وكذلك تساعد في تغيير المزايا التنافسية للبلدان، وربط المؤسسات البعيدة ببعضها البعض، ونشر الخدمات المالية على نطاق عالمي، وكذلك إثارة مشكلات جديدة او العكس فتح فرص جديدة أمام تنمية ونمو أفقر البلدان .
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The principal components analysis is used in analyzing many economic and social phenomena; and one of them is related to a large group in our society who are the university instructors. This phenomenon is the delay occurred in getting university instructor to his next scientific title. And as the determination of the principal components number inside the principal components depends on using many methods, we have compared between three of these methods that are: (BARTLETT, SCREE DIAGRAM, JOLLIFFE).
We concluded that JOLLIFFE method was the best one in analyzing the studying phenomenon data among these three methods, we found the most distinguishing factors effecting on t
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يهدف البحث إلى تحقيق عدد من الأهداف: الكشف عن مدى تفاعلية الجمهور إزاء استخدام التطبيقات الإعلانية في الفضائيات عبر أجهزة الهاتف المحمول. التعرف على تفضيلات الجمهور بين التطبيقات. الوقوف على أهم الموضوعات التي يفضل الجمهور التفاعل معها في التطبيقات الإعلانية. الكشف عن أبرز المعوقات التي تواجه مستخدمي التطبيقات الإعلانية في الفضائيات عبر الهاتف المحمول. الوقوف على مدى مساهمة التطبيقات الإعلانية في الفضائي
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Research summarized in applying the model of fuzzy goal programming for aggregate production planning , in General Company for hydraulic industries / plastic factory to get an optimal production plan trying to cope with the impact that fluctuations in demand and employs all available resources using two strategies where they are available inventories strategy and the strategy of change in the level of the workforce, these strategies costs are usually imprecise/fuzzy. The plant administration trying to minimize total production costs, minimize carrying costs and minimize changes in labour levels. depending on the gained data from th
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The researcher studied transportation problem because it's great importance in the country's economy. This paper which ware studied several ways to find a solution closely to the optimization, has applied these methods to the practical reality by taking one oil derivatives which is benzene product, where the first purpose of this study is, how we can reduce the total costs of transportation for product of petrol from warehouses in the province of Baghdad, to some stations in the Karsh district and Rusafa in the same province. Secondly, how can we address the Domandes of each station by required quantity which is depending on absorptive capacity of the warehouses (quantities supply), And through r
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كثيرة هي البحوث والدراسات التي نراجعها في السلوك التنظيمي، بحكم عملنا كأستاذ دراسات عليا بتخصص ادارة الموارد البشرية ونظرية المنظمة، ووقع بيننا بحثاً نظرياً متميزاً للباحثين
(Karin Sanders & Birgit Schyns)([1])، نشر في مجلة اصيلة هي (Personnel Review)، في عام (2006)، بمجلدها (35) وبالعدد (5)، تحت عنوان (Trust, Conflict and Cooperative Beha
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Abstract
Bivariate time series modeling and forecasting have become a promising field of applied studies in recent times. For this purpose, the Linear Autoregressive Moving Average with exogenous variable ARMAX model is the most widely used technique over the past few years in modeling and forecasting this type of data. The most important assumptions of this model are linearity and homogenous for random error variance of the appropriate model. In practice, these two assumptions are often violated, so the Generalized Autoregressive Conditional Heteroscedasticity (ARCH) and (GARCH) with exogenous varia
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Abstract
The study aims to identify the degree of citizenship values practiced by Bisha University students and identify the impact of gender, college, and academic level, on the degree of the practice of University students for citizenship values. The researcher used the descriptive-analytical method including a questionnaire of (44) items. To process the data, the researcher applied the computational averages, standard deviations, percentages, and T-test. The questionnaire was implemented on a sample of (600) of the 2 and 8 levels during the second semester of the academic year (2020-2019) at Bisha University. The study findings revealed that the degree of the pra
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