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تحضير ودراسة جسيمات الفضة النانوية وتاثيرها المضاد للبكتيريا == Preparing and Studying Nano Silver Particles and Their Anti Bacterial Effect

اسم المؤلف: سماح صباح عبد الرزاق
اسم المشرف: ثامر عبد الجبار جمعة
الموضوع العام: علوم الفيزياء
السنة: 2017
الموضوع الدقيق: الفيزياء
الدرجة: ماجستير
الجامعة: جامعة النهرين - كلية العلوم - قسم الفيزياء
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: The target of this research is to prepare nano silver particles by laser ablation in both deionized and magnetized water. The properties of nano silver particles and their bacterial effects with different parameters’ were studied. The magnetic water was laboratory preparing by square magnets with magnetic flux of 200 mT applied on the deionized water which pass through it 10ns Q.swiched Nd - YAG laser of wave length 1064nm with different energies and different laser pulses number were used with and without applied electric field. Optical properties for the nano silver colloidal by UV - Vis technique was investigate. The absorption for the silver spectrum was found lied at 420 - 430nm, i.e. involved visible region. The absorption peaks have different height due to different both the shape and concentration of nano silver in the colloidal.TEM technique was used for investigating both size and shape of nano silver particles. The nano silver particles have different shapes such spherical, spindles, etc…. depending upon two parameters is laser energy and laser pulses number. The effect of nano silver particles on bacteria growth of three types of bacteria (staph, ps., E.coli) were studied in details under effect of applied electric field of 3000V/m. There is no inhibition zone was obtained when used different silver colloidal except the colloidal prepared under 600mJ and 1000laser pulses, where this colloidal gives an effected property and ability to determine the bacteria growth type ps. In the range of inhibition of 25nm.The results of the TEM show that the shape of nanoparticles affecting the growth of bacteria was spherical and its size ranges between32 - 50nm.

استخدام طريقة للتبع نقطة الطاقة القصوى على اساس الحرارة للسطوح الكهروضوئية باستخدام برنامج PSPICE == Maximum Power Point Tracking approach based on Temperature for PV Surfaces using PSPICE program

اسم المؤلف: حارث محمد سعيد حامد
اسم المشرف: زينب منذر يونس كبة
الموضوع العام: علوم الفيزياء
السنة: 2017
الموضوع الدقيق: الفيزياء
الدرجة: ماجستير
الجامعة: جامعة النهرين - كلية العلوم - قسم الفيزياء
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: This research study the effect of Photovoltaic surface temperature on Photovoltaic panel output characteristics. First, circuit simulator PSPICE was used to compose Photovoltaic panel model at 75 W, 4.8 A and 21 V. Then, study the behaviorof it under varying conditions (solar insolation, environmental temperature and PV panel surface temperature). ABM feature of PSPICE was used to include the above parameters in PV PSPICE model and produced temperature dependent voltage. The voltageconverted to current with galvanic insolation by element Gploy with gain 0.8. The model defined as hierarichal block in PSPICE library and could be called as individual source for any applications.After studying the effect of PV surface temperature on its (IV) curves specially the position of the maximum power point, this temperature was used to keep tracking of the optimal voltage for the PV panel at the MPP. Therefore DC - DC boost converter was used to achieve this purpose.Boost converter was raise a PV panel voltage from 17 V to 34 V for all variation of surface temperature from 300 K to 350 K at frequency 10 KHz and ΔVo = 5 V.

طريقة مهجنه لحل المعادلات التفاضلية الضبابية من الرتبة الثانية == A Hybrid Approach for Solving Fuzzy Differential Equation of Second Order

اسم المؤلف: بسمه عبد الهادي نعمة
اسم المشرف: علاء الدين نوري احمد
الموضوع العام: علوم الرياضيات
السنة: 2017
الموضوع الدقيق: الرياضيات
الدرجة: ماجستير
الجامعة: جامعة النهرين - كلية العلوم - قسم الرياضيات وتطبيقات الحاسب
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: In this thesis, a hybrid approach is presented by combining fuzzy Laplace transformation method and fuzzy variational iteration methods which is employed to obtain approximate solutions of linear and nonlinear fuzzy differential equations with fuzzy initial and boundary values. Then our approach is implemented in which two approaches have been constructed according to the formula of the Lagrange multiplier obtaining the lower, upper and center solutions. The experimental results which are obtained shows every high accuracy in comparison with the exact results with less number of iterations other numerical or approximate method.

الحلول العددية للمعادلات التكاملية - الجبرية == Numerical Solutions of Integral - Algebraic Equations

اسم المؤلف: صفاء حسن رسول
اسم المشرف: اسامة حميد محمد
الموضوع العام: علوم الرياضيات
السنة: 2017
الموضوع الدقيق: التحليل العددي
الدرجة: ماجستير
الجامعة: جامعة النهرين - كلية العلوم - قسم الرياضيات وتطبيقات الحاسب
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: In this thesis two approximate methods are implemented in order to find the approximate solutions of the linear system of Volterra integral - algebraic equations which are so - called Hat basis functions and Sample - and - Hold functions.Both methods will transform the linear system of Volterra integral - algebraic equations to a linear lower triangular system of algebraic equations using the operational matrices of integration associated with the Hat basis functions and Sample - and - Hold functions.Convergence theorem and tested examples are given in order to check the validity and efficiency of the proposed methods

حل عددي لمعادلة برجر فيشر باستخدام اسلوب مويجات هار == NUMERICAL SOLUTION VIA HAAR WAVELET APPROACH FOR BURGER'S FISHER EQUATION

اسم المؤلف: نوار حازم محمد
اسم المشرف: علي حسن ناصر الفياض
الموضوع العام: علوم الرياضيات
السنة: 2017
الموضوع الدقيق: التحليل العددي
الدرجة: ماجستير
الجامعة: جامعة النهرين - كلية العلوم - قسم الرياضيات وتطبيقات الحاسب
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: في هذه الرسالة، تم تطبيق طريقة مويجات هار بكفاءة في ايجاد الحل العددي لمعادلة برغر فيشر. اظهرت هذه الطريقة تقاربا سريعا بالنسبة الى الطرائق الاخرى. وتشير الامثلة التوضيحية الى ان استخدام طريقة المويجات تزود بطريقة قوية لايجاد الحلول العددية لمعادلة برغر فيشر. اظهرت المقارنة بين النتائج العددية والحل التام والحلول التي تم الحصول عليها باستخدام بعض الطرق التقليدية مثل طريقة التكرار التبايني (VIM), ان الطريقة المقترحة تعطي نتائج دقيقة الى حد ما لحل مسالة برجر فيشر | In this thesis, Haar wavelet method is implemented efficiently in finding the numerical solution of Burger's Fisher equation. This method shows rather rapid convergence than other existing methods. Illustrative examples are implemented to show the efficiency and the powerful of Haar wavelet approach. The comparison among the numerical results and the exact solution, and the solutions obtained by using some traditional methods such as variational iteration method (VIM) shows that the suggested scheme is fairly accurate and viable for solving Burger's Fisher problem.

الحلول العددية للمعادلات التفاضلية الخطية ذات الرتبة الكسرية المتغيرة باستخدام متعددات حدود بيرنشتاين == The Numerical Solution of Linear Variable Order Fractional Differential Equations Using Bernstein Polynomials

اسم المؤلف: الشيماء عبد الفتاح عمر
اسم المشرف: اسامه حميد محمد
الموضوع العام: علوم الرياضيات
السنة: 2017
الموضوع الدقيق: التحليل العددي
الدرجة: ماجستير
الجامعة: جامعة النهرين - كلية العلوم - قسم الرياضيات وتطبيقات الحاسب
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: The main theme of this thesis is oriented about three objects : The first objective is to study the basic concepts of fractional calculus and variable - order fractional differential equations.The second objective is about solving numerically the variable - order fractional differential equations using operational matrices of Bernstein polynomials.The proposed approach will transform the variable - order fractional differential equations into the product of some matrices which can be considered as a linear system of algebraic equations, after solving the resulting system the numerical solution can be obtained.The third objective is to find the numerical solution of multiterm variable - order fractional differential equations using operational matrices of Bernstein polynomials, also the proposed method will transform the multiterm variable - order fractional differential equations into the product of matrices in other words into a system of linear algebraic equations, and the numerical solution will be reached after solving the resulting system.

بعض نتائج طرق التحولات الرياضية وتطبيقها في ضغط الصورة == Some Results of Mathematical - Based Transformation Methods and their Application to Image Compression

اسم المؤلف: هديل ماجد رشيد العاني
اسم المشرف: علي حسن ناصر الفياض
الموضوع العام: علوم الرياضيات
السنة: 2017
الموضوع الدقيق: الرياضيات
الدرجة: ماجستير
الجامعة: جامعة النهرين
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: The main purpose of this thesis is to study and investigate the most important properties of integral transforms ( the discrete fourier transform, the discrete sine transform, and the discrete wavelet transform) and their mathematical aspects both from the theoretical point of view and for the application to image compression.As well as, we study the singular value decomposition method and its application to image representation.Two mathematical models are developed. The first model consists of a new multi - transform method that takes advantage of each of the discrete wavelet transform and the singular value decomposition method while the second model takes advantage of the discrete sine transform and the singular value decomposition method. These models are applied to compress images. Results show that this new approach yields better function representation and reconstruction in image compression application than is possible with the use of a single fixed transform. The proposed models improve the efficiency of the compressing process in the discrete wavelet transform and the discrete sine transform domains

طريقة الاتجاه التكراري المتناوب المطورة لحل المعادلات التفاضلية الجزئية مع تطبيق على الجروح المزمنة لمرضى السكر

اسم المؤلف: میلاد جمیل حمو
اسم المشرف: فاضل صبحي فاضل
الموضوع العام: علوم الرياضيات
السنة: 2017
الموضوع الدقيق: الرياضيات
الدرجة: ماجستير
الجامعة: جامعة النهرين - كلية العلوم - قسم الرياضيات وتطبيقات الحاسب
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: Alternating Direction Implicit method (ADI) was first suggested by Peaceman and Rachford in the mid - 50s of the last century for solving systems of algebraic equations in two dimension of spaces[peaceman and rachford,1955], which results from the finite difference discretization method for solving PDEs; [Peaceman and Rachford,1955]. From iterative method’s perspective, the ADI method may be considered as a special relaxation method, where a big system is simplified into a number of smaller sub - systems, such that each of them may be solved efficiently and the solution of the whole system is then obtained from the solutions of the sub - systems in an iterative method approach, [Al - Saif and Al - Kanani,2011].The main theme of this thesis may be directed toward three objective : The first objective is to explain and clarify, in details, the alternative direction iteration method in a simple way for each type of differential equations, which is produced by rearranging the Crank - Nicholson formulation and discuss the stability, convergent and consistency of the solution using normal time steps. we preposed a new alternative direction iteration method depending on another time step, a new formula derived to give alternative direction iteration method more accurate.The second objective is to derive and study the system associated with the infected equations of patients with diabetes then the effect of oxygen in the treatment of infected wounds, the obtained system of related equations was of the first dimension, also the alternative direction iteration method could be genarlized to solve the equations of the second dimension. Then we went to re - model the part of this system of equations of the second dimension as a prelude to solve. Finally, the third objective is devoted to solve a system of equations that re - modeled by using the discussed alternative direction iteration method the results that are obtaind to find out how the stability of the system output and the accuracy of the results affect on the stages of treatment.
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