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- ItemAnalysis of radiant heat exchange and interaction with conduction(Al-Quds University, 2009-04-09) Imad Ali Hamdan Al Atrash; عماد علي حمدان الأطرشThis work deals with the three fundamental concepts of heat transfer modes (radiation, conduction and convection) with great emphasis on heat radiation and interaction with conduction. Determining radiation interchange between surface areas is needed in heat transfer, illumination engineering and applied optics. In fact, since 1960 the study of radiant interchange has been given impetus by technological advances that provides systems in which thermal radiation is very important. The geometric configuration factors derived here are an important component for analyzing radiation exchange. The computation of configuration factors involves integration, either analytically or numerically, over the solid angles by which surfaces can view each other. Some examples are given to demonstrate analytical integrations arise in radiant heat analysis. Moreover, the question of coupling heat radiation with conduction has been dealt with. To analyze this problem we consider a conductive - radiative heat transfer model containing two conducting and opaque materials which are in contact by radiation through a transparent medium bounded by diffuse - grey surfaces. Some properties of the radiative integral operator are presented. The question of existence and uniqueness of weak solutions for this problem is investigated. The existence of weak solution is proved by showing that our problem is pseudo-monotone and coercive. The uniqueness of solution is proved using some ideas from the analysis of nonlinear heat conduction.
- ItemApproximate Solutions of Einstein Field Equations(Al-Quds University, 2017-05-21) Mousa Saaed Mohammed Emter; موسى سعيد محمد مطيرEinstein eld equations (EFEs) play an important role in understanding the theory of general relativity and related phenomena such as gravitational waves. Since, in general, it is almost impossible to nd analytical solutions of EFEs, it is necessary to solve these equations numerically (approximately). In this work, we derive the Einstein eld equations (EFEs) and the standard ADM (Arnowitt, Deser and Misner) equations form of EFEs. The ADM form consists of constraint equations and evolution equations for the raw spatial metric and extrinsic curvature tensors. The corner stone in the derivation of this form is \3+1 formalism", where one splits spacetime into three-dimensional space on the one hand, and time on the other. We study the BSSN (Baumgarte, Shapiro, Shibata and Nakamura) formulation. In this formulation the ADM equations were modi ed by factoring out the conformal factor and introducing three connections. The evolution equations can then be reduced to wave equations for the conformal metric components, which are coupled to evolution equations for the connection functions. Small amplitude gravitational waves were evolved and a direct comparison of the numerical performance of the modi ed ADM equations with the standard ADM equations was made. The results demonstrate that the standard implementation of the ADM system of equations, consisting of evolution equations for the bare metric and extrinsic curvature variables, is more susceptible to numerical instabilities than the modi ed form of the equations based on a conformal decomposition as suggested by Shibata and Nakamura. Further, in this work, we consider the problem of specifying Cauchy initial data in the case 3+1 formalism. We also apply the Optimal Homotopy Asymptotic Method, OHAM, and solving the Einstein eld equations corresponding to Schwarzschild geometry, i.e. we determine the Schwarzschild solution using OHAM.
- ItemFractional Calculus in Economics(Al-Quds University, 2021-12-21) Ayed Mohammad Abdullah Alfawaqa; عائد محمد عبد الله الفواقهFractional Calculus has become used in many applications in various types of science and it has many important applications. In this thesis, we referred to the most important definitions of the subject of fractional calculus and studied some of important applications of it. In economic sciences in particular, many countries have become using fractional calculus in their economic calculations, such as calculating the gross domestic product and demand elasticity and supply elasticity. In this thesis, we focused on the uses of fractional calculus in economic and financial sciences, and we studied the application of fractional calculus in calculating the gross domestic product of Spain as a case study, and analyzed and compared the results. At the end of this thesis, we applied fractional calculus in calculating the gross domestic product of Palestine using fractional calculus. The fractional calculus, as we have shown in this thesis, can provide results characterized by high quality and accuracy if it used in many different scientific and research fields. يعتبر حساب التفاضل والتكامل الكسري من العلوم التي تم استخدامها مؤخرا في العديد من التطبيقات العلمية في مختلف المجالات الطبية والهندسية والرياضية والاقتصادية وغيرها من العلوم ، وقد كان لاستخدام حساب التفاضل والتكامل الكسري العديد من المزايا التي ساهمت في زيادة دقة التطبيقات العلمية وكفاءتها. إن استخدام حساب التفاضل والتكامل في العلوم الاقتصادية له أثر كبير في تحسين الحسابات المتعلقة بالاقتصاد في العديد من دول العالم ، وقد تميزت الحسابات الخاصة بالناتج المحلي الإجمالي للدول بالدقة والكفاءة العالية مقارنة بالحسابات التقليدية . في هذه الرسالة بحثنا استخدامات التفاضل والتكامل الكسري في العديد من العلوم ، وقد سلطنا الضوء على استخدامات التفاضل والتكامل الكسري في مجال الاقتصاد وخصوصا في حساب الناتج المحلي الاجمالي للدول ومقارنة الحسابات التي تم استخدام التفاضل والتكامل الكسري فيها بالحسابات التقليدية ، ومن خلال النتائج يمكننا القول بأن استخدام التفاضل والتكامل الكسري في الحسابات الاقتصادية سيؤدي الى زيادة الدقة والجودة في تلك الحسابات، كما أن الباب ما زال مفتوحا لاستخدامات أخرى لحساب التفاضل والتكامل الكسري في مجالات أخرى في العلوم الاقتصادية وغيرها من العلوم .
- ItemGeneralized Log-Logistic Proportional Hazard Model with Applications in Survival Analysis(Al-Quds University, 2022-08-10) Afnan Mahmoud Mustafa AL-sheikh; افنان محمود مصطفى الشيخProportional hazard (PH) models can be formulated with or without assuming a probability distribution for survival times. The former assumption leads to parametric models, whereas the latter leads to the semi-parametric Cox model which is by far the most popular in survival analysis. However, a parametric model may lead to more efficient estimates than the Cox model under certain conditions. Only a few parametric models are closed under the PH assumption, the most common of which is the Weibull that accommodates only monotone hazard functions. We study and investigate a generalization of the log-logistic distribution that belongs to the PH family. It has properties similar to those of log-logistic, and approaches the Weibull in the limit. These features enable it to handle both monotone and nonmonotone hazard functions. Application to four data sets and a simulation study revealed that the model could potentially be very useful in adequately describing different types of time-to-event data. يمكن صياغة نماذج المخاطر النسبية Proportional Hazardمع أو بدون افتراض توزيع احتمالي لأوقات البقاءSurvival Time. يؤدي الافتراض الأول إلى نماذج بارامترية Parametric، في حين أن الأخير يؤدي إلى نموذج كوكس Coxشبه البارامتي الذي يعد الأكثر شيوعًا في تحليل البقاء على قيد الحياة. ومع ذلك، قد يؤدي النموذج المعياري إلى تقديرات أكثر كفاءة من نموذج كوكس في ظل ظروف معينة.عدد قليل فقط من النماذج البارامترية في ظل افتراض PHتكون مغلقة، وأكثرها شيوعًا هو Weibull الذي يستوعب اقترانات الخطر أحادية الاتجاه فقط في هذا البحث سوف ندرس ونتوسع في تعميم التوزيع اللوجيستي الذي ينتمي إلى عائلة PH. لها خصائص مشابهة لتلك الخاصة باللوجستيات ، وتقترب من Weibull في النهاية. هذه الميزات تمكنه من التعامل مع اقترانات الخطر monotone and nonmonotone hazard function .تم تطبيق هذا النموذج على مجموعات مختلفة من البيانات وكذلك دراسة محاكاة، تبين أن النموذج يمكن أن يكون مفيداً جداً في وصف الأنواع المختلفة من بيانات الوقت إلى الحدثtime-to-event بشكل مناسب.
- ItemGeneralized Log-Logistic Proportional Hazard Model with Applications in Survival Analysis(Al-Quds University, 2022-08-10) Afnan Mahmoud Mustafa AL-sheikh; افنان محمود مصطفى الشيخيمكن صياغة نماذج المخاطر النسبية Proportional Hazard مع أو بدون افتراض توزيع احتمالي لأوقات البقاء Survival Time. يؤدي الافتراض الأول إلى نماذج بارامترية Parametric، في حين أن الأخير يؤدي إلى نموذج كوكس Cox شبه البارامتي الذي يعد الأكثر شيوعًا في تحليل البقاء على قيد الحياة. ومع ذلك، قد يؤدي النموذج المعياري إلى تقديرات أكثر كفاءة من نموذج كوكس في ظل ظروف معينة. عدد قليل فقط من النماذج البارامترية في ظل افتراض PH تكون مغلقة، وأكثرها شيوعًا هو Weibull الذي يستوعب اقترانات الخطر أحادية الاتجاه فقط في هذا البحث سوف ندرس ونتوسع في تعميم التوزيع اللوجيستي الذي ينتمي إلى عائلة PH. لها خصائص مشابهة لتلك الخاصة باللوجستيات ، وتقترب من Weibull في النهاية. هذه الميزات تمكنه من التعامل مع اقترانات الخطر monotone and nonmonotone hazard function .تم تطبيق هذا النموذج على مجموعات مختلفة من البيانات وكذلك دراسة محاكاة، تبين أن النموذج يمكن أن يكون مفيداً جداً في وصف الأنواع المختلفة من بيانات الوقت إلى الحدث time-to-event بشكل مناسب.
- ItemA Generlized Defenition of the Fractional Derivative with Application in Newtonian Mechanics(Al-Quds University, 2023-05-27) Samah Mousa Kalaf Bajali; سماح موسى خلف بجاليThis work studies the proposed new generalized fractional derivative (GD) definition, showing that the index law 𝐷𝛼𝐷𝛽𝑓(𝑡) = 𝐷𝛼+𝛽𝑓(𝑡); 0 < 𝛼,𝛽 ≤ 1 works for a differentiable function expanded by a Taylor series. (GD) is applied for some functions, the results are compared with Caputo fractional derivative. The solutions of some fractional differential equation are obtained via the (GD) operator. A comparison with the conformable derivative (CD) is also discussed. Newtonian Mechanics is discussed in the light of the fractional calculus. يدرس هذا العمل التعريف الجديد المعمم للاشتقاق الكسري (GD)، والذي يوضح أن قانون المؤشر D^α D^β f(t) = D^(α+β) f(t); 0 < α,β ≤ 1 تنطبق على جميع الاقترانات القابلة للتفاضل موسعة بواسطة سلسلة تايلور. يتم تطبيق (GD) على بعض الاقترانات ومقارنة النتائج مع مشتقة Caputo الكسرية. يتم الحصول على حلول بعض المعادلات التفاضلية الكسرية عبر عامل التشغيل (GD). كما تمت مناقشة النتائج مع تعريف (CD) للاشتقاق الكسري. كما تمت مناقشة ميكانيكا نيوتن في ضوء حساب التفاضل والتكامل الكسري.
- ItemLinear Regression Models Assuming a Stable Distribution with Applications(Al-Quds University, 2020-08-31) Layla Khaled Mahmoud Lahaleeh; ليلى خالد محمود اللهاليه
- ItemMultivariate Time Series with Application On Recurrent Neural Networks(Al-Quds University, 2020-06-12) Safa Nader Mustafa Shanaa; صفاء نادر مصطفى شناعةMultivariate time series data in practical applications, such as health care, geosciences, engineering, and biology. This thesis introduces a survey study of time series analysis to recurrent neural networks research, an analytic domain that has been essential for understanding and predicting the behavior of variables across many diverse fields, in this research the following were investigated. First, the characteristics and preliminaries of time series data are investigated and discussed, including various time series models, specially, Autoregressive Models such as, AR, MA, ARMA, and ARIMA. Frequently one wishes to fit a parametric model to time-series data and determine accurate values of the parameters and reliable estimates for the uncertainties in those parameters. It is important to gain a thorough understanding of the noise and develop appropriate methods for parameter estimation, so that various approaches of parameter estimates will be considered in this thesis, such as, yules walker method, least square method, method of moments and maximum likelihood approach. Second, different time series modeling techniques are surveyed that can address various topics of interest to artificial neural networks researchers, including describing the pattern of change in a variable, modeling seasonal effects, assessing the immediate and long-term impact of a salient event, and forecasting future values. The structure of the artificial neural networks especially the recurrent neural networks were discussed in details in this research, concerning on GRUs and LSTMs, and their properties, also some difficulties that arises in recurrent neural networks such as vanished gradient and the overfitting were discussed. To illustrate these approaches, an illustrative application based on Monte Carlo and bootstrapping methods is used throughout the research, constructing a one layer hidden recurrent neural networks and applied back-propagation, for the purpose of comparison, the variance of error in each method was estimated.
- ItemOptimal Homotopy Asymptotic Method for Solving Multidimensional First Order Systems of Partial Differential Equations(Al-Quds University, 2024-07-15) Malak Tawfiq Abdelfattah Meqbil; ملاك توفيق عبدالفتاح مقبلIn this thesis, a semi-analytic approximating method, namely Optimal Homotopy Asymptotic Method (OHAM), which is developed from the Homotopy Analysis Method (HAM), is used to find continuous approximate solutions for linear and non-linear first-order systems of partial differential equations. Within this work, the geometrical topological homotopy concept is used to construct the algorithm for solving such systems. A homotopy equation that depends on an embedding parameter belonging to interval [0, 1] is assumed. As the parameter varies from 0 to 1 the solution of the homotopy equation (which is assumed to be a power series of the embedding parameter) varies continuously from a solution, which is easy to find, to the exact solution. The approximate continuous solution is obtained by truncating the series and using a finite number of its terms. Least Squares Method is used to determine the so-called control-convergence parameters that appear in the approximate solution. The derived algorithm is applied to solve some examples and the obtained solutions are compared with exact solutions. The results confirm the validity of OHAM and reveal that OHAM is effective, simple, and explicit. Moreover, it is independent of the small parameters required in perturbation methods. Furthermore, the convergence domain of OHAM is easily modifiable, depending on the convergence-control parameters that appear in the approximated solutions, enhancing its versatility.
- Itemالاتصال ما بين اقترانات متجهات الفضاءات المترية(AL-Quds University, 2016-01-09) تهاني صبحي جبريل القادري; Tahani Sobhi Jebril Alqaderi; إبراهيم الغروز; د. يوسف زحايكة; د. احمد خمايسة
- Itemالاشتقاق الجزئي لنبلا ودلتا كبتو وحده الثنائي(AL-Quds University, 2016-01-09) دعاء عمر موسى عمرو; Duaa omar mousa amro; ابراهيم الغروز; جميل جمال; حمد خمايسة
- Itemالتراص و اللندلوف لتبولوجيا بالنسبة لآخر في التبولوجيا الثنائية(AL-Quds University, 2001-07-21) فاتن ذياب عقل تركمان; Faten Diab aqel Turkman; يوسف بدير; محمد خليل; مهيب أبو لوحة