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تحسين خوارزميات الحل التام والبحث المحلي لحل بعض مسائل الامثلية التوافقية == Improving Exact and Local Search Algorithms for Solving Some Combinatorial Optimization Problems

Author name: فائز حسن علي
Supervisor name: طارق صالح عبد الرزاق
General topic: Mathematics
Specific topic: Numerical Optimization
Degree: Doctorate
University: Mustansiriyah University - College Of Education For Pure Sciences - Department Of Mathematics
Language: English
University location: Baghdad
First pages:
Abstract: In mathematics and computer science, an optimization problem (OP) is the problem of finding the best solution from all feasible solutions. OPs can be divided into two categories depending on whether the variables are continuous or discrete. An OP with discrete variables is known as a combinatorial optimization problem (COP). In a COP, we are looking for an object such as an integer, permutation or graph from a finite set.The aim of the research presented in this thesis is to investigate the use of various optimization exacts and heuristics to solve the COP's. This thesis presented in six chapters.In this thesis we interest in discussing three samples of COP; machine scheduling problem (MSP), transposition cipher problem (TCP) and aircraft landing problem (ALP).In the first two chapters, we discuss the main concepts of the COP, the three study cases, the basic techniques and methods for solving the COP respectively.In chapter three, we interesting in MSP, with multiple objective for the 1//(Ci,Ti) problem (P1) and 1//Ci+Ti problem (P3). We investigate the usefulness of precedence rules in solving (P1) and (P3). We found that the complete enumeration method (CEM) gives efficient (and optimal) solutions for (P1) (and (P3)) with number of jobs (n)10, and branch and bound (BAB) gives efficient solutions for (P1) with n15 and optimal solution for (P3) with n80. In addition, we use the local search methods (LSM), to solve the two problems, represented by genetic algorithm (GA) and particle swarm optimization (PSO) with n2000. In general we conclude that PSO serves better than GA. Lastly, a neural network (NN) is constructed to solve problems (P1) and (P3). Two learning algorithms are used to learn the NN; pack propagation (PB) and PSO with and without depending on successive rules (SR). We see that PSO is better than BP in learning NN to obtaining good results.In chapter four, we suggest a new direction in cryptanalysis of TCP, we suggest using the techniques of COP to solve TCP in another word, the TCP treated as one of COP. First a new mathematical formulation for TCP is introduced and proposed some new tools of TCP cryptanalysis. The CEM and modified BAB are developed by using SR to obtain the multi digits CEM (MDCEM) and MDBAB which are helpful in decreasing the CPU time. Classical bees' algorithm (CBA) and shifted key BA (SKBA) are improving the cryptanalysis results. To increase the performance of the mentioned algorithms we construct cryptanalysis system for TCP to find exact solution (as possible) for n20 in reasonable time, which is called SR keys BA (SRKBA). The main result of this thesis is suggesting a general solving system for COP specially, when the problem submits to SR.Chapter five focused in one of the important problems of COP; ALP. A new improvement in a heuristic method, called parallel improving algorithm (PIA), is introduced, the new algorithm called modified PIA (MPIA) which is serves better than PIA. The CEM is used to solve ALP using two techniques; exhaustive search method (ESM) which gives optimal solution but in unreasonable time for n>9 while MPIA gives approximation solutions for n9 in 6 seconds. Lastly, hybridization is proposed between MPIA and CBA, which is called improvement CBA (ICBA). ICBA gives optimal solutions in solving ALP for n<50 and near optimal for n=50.In chapter six, some conclusions together with some suggestions for future researches have been given.The exact and heuristics methods all were tested by programming them using version 10.0 of Delphi Language and MATLAB, and running on Processor Intel(R) Core (TM) i3 CPU, 2.53 GHz, Core(s), with Ram 1.21 GB computer.

مسالة السيطرة الامثلية التقليدية المستمرة لمعادلات تفاضلية جزئية == The Continuous Classical Optimal Control Problem of Partial Differential Equations

Author name: غفران مناتي كاظم
Supervisor name: جميل اميرعلي الهواسي
General topic: Mathematics
Specific topic: Mathematics
Degree: Master
University: Mustansiriyah University - College Of Education For Pure Sciences - Department Of Mathematics
Language: English
University location: Baghdad
First pages:
Abstract: الهدف الرئيسي لهذه الرسالة هو دراسة مسالة السيطرة الامثلية التقليدية المستمرة لزوج من المعادلات التفاضلية الجزئية الخطية واللاخطية من النوع المكافئ )stateفي برهان مبرهنة وجود ووحدانية الحل للحالة ( Galerkin حيث استخدمنا طريقة لزوج من المعادلات المذكورة اعلاه ولكن من النوع اللا خطي عندما يكون متجه السيطرة التقليدية المستمرة ثابت . قمنا ايضا ببرهان مبرهنات خاصة بوجود سيطرة (متجه السيطرة) التقليدية المستمرة لزوج من المعادلات التفاضلية الجزئية الخطية واللاخطية من النوع المكافئ. برهنا ايضا مبرهنة وجود ووحدانية الحل لزوج المعادلات التفاضلية الجزئية الخطية واللاخطية للحالة. طورت بشكل يتناسب مع المسالة Kuhn - Tucker - Lagrange’s Multipliers مبرهنات السيطرة التقليدية المستمرة المقترحة في هذه الرسالة وصيغت وبرهنت مبرهنتا الشرط الضروري لوجود السيطرة الامثلية | The main aim of this thesis is to study the continuous classical optimal control problem of a couple of linear and nonlinear parabolic partial differential equations. With a suitable assumptions, the existence and the uniqueness of solution of the state vector of couple of linear parabolic PDEs for a given continuous classical control vector are proved by using Galerkin method. The existence theorems of a continuous classical optimal control vector associated with a couple of nonlinear parabolic equations are developed and proved. The existence and the uniqueness theorem of a solution of the couple of adjoint equations associated with the considered state equations of nonlinear parabolic equations with equality and inequality constraints is also proved once again. The Kuhn - Tucker - Lagrange multipliers theorems are developed and used to prove the necessary conditions theorem and the sufficient conditions theorem of optimality of a couple of nonlinear parabolic equations with equality and inequality constraints

الحل العددي لبعض المعادلات التفاضليه باستخدام تحويل لاكير == Numerical Solution for some Differential Equations via Laguerre Transform Approach

Author name: غصون سعيد عبد محمد
Supervisor name: ايمان علي حسين
General topic: Mathematics
Specific topic: Numerical Analysis
Degree: Master
University: Mustansiriyah University - College Of Education For Pure Sciences - Department Of Mathematics
Language: English
University location: Baghdad
First pages:
Abstract: The main aim of this work is to introduce new formulae that can be used to deal with LT and to utilize them for solving different types of DEs.A new simple general formula is derived to evaluate the LT of the higher derivatives of a variable. The new formula is easily modeled by a computer program, and there is no need for tedious operations of successive integration by part, as in the conventional method.This work proposes a method utilizing LT to solve ODE's (linear and nonlinear, homogeneous or inhomogeneous, boundary or initial value problems), which is explained and implemented in different examples. The results are in a good agreement with the analytical solution.Two other new methods are proposed, utilizing LT to solve PDE's with one spatial dimension. The two methods are explained and implemented in different examples, and the results show a good agreement with the analytical solutions.Another new method, utilizing LT, is proposed to solve PDE's with two spatial dimensions. The method is implemented to solve heat equation with two spatial dimensions and the results show a good agreement with that of finite difference solution. The method is also modified to achieve image smoothing as a global smoothing technique. The new image smoothing technique is compared with a finite difference technique for image smoothing, which is a local smoothing technique. The results of the proposed new technique show better smoothing (less fogy) with an expenditure of a long execution time.Finally, it is worth to mention that all the programs used in this work have been coded by the MATLAB 7 system environment

الجدوله لمقاييس متعددة الاداء == Scheduling with Multiple Performance Measures

Author name: علي عباس نعمان المالكي
Supervisor name: طارق صالح عبد الرزاق
General topic: Mathematics
Specific topic: Mathematics
Degree: Master
University: Mustansiriyah University - College Of Education For Pure Sciences - Department Of Mathematics
Language: English
University location: Baghdad
First pages:
Abstract: في هذه الرسالة تصغير دالة لمعياريين او ثلاثة والحاصلة من جدولة n من الاعمال على ماكنة واحدة . تم التركيزفي هذه الدراسة والاخذ بنظر الاعتبار على حالة التاخير اللاسالب والعمل المتاخر ووقت الاتمام الكلي . ونوقشت المسائل التالية : 1 . تصغير الدالة (Tmax+Vmax) . 2 .تصغيرالدالة ذات ثلاث معايير والتي تاخذ الصيغة Lex(Tmax+Vmax ,Σ■(n@i)Ci) وLex(Σ■(n@i)Ci , Tmax+Vmax ) . . (■(n@i)Ti + ■(n@i)Vi) تصغير الدالة .3 للمسالة الاولى اقترحنا خوارزمية التفرع والتقييد لايجاد الحل الامثل كذلك برهنا بعض الحالات الخاصة التي تؤدي الى الحل الامثل .كذلك اقترحنا خوارزمية (A) المطورة من خوارزمية لولر لحل المسالة وهذا قادنا الى ملاحظة مشجعه وهي ان اغلب النتائج الحسابية تؤدي الى الحل الامثل. كما واجرينا تجارب حسابية لطريقة التفرع والتقييد على مجموعة كبيرة لمسائل اختبارية. .للمسالة الثانية والتي هي تعميم للمسالة الاولى قمنا باستخدمنا قاعدة (SPT) وكذلك الخوارزمية (A) المطورة لايجاد افضل الحلول . للمسالة الثالثة اقترحنا خوارزمية التفرع والتقييد مع قيدين سفلي وقيد علوي الذي هو اصغر ثلاث قيود تقريبيه مقترحة لايجاد الحل كذلك برهنا بعض الحالات الخاصة واستخدمنا قواعد الهيمنة مع خوارزمية التفرع والتقييد لتحسين النتائج الحسابية لهذه المسالة. | This thesis intends, to minimize a function of two and three cost criteria for scheduling n jobs on a single machine. The study focuses on the case where Tardiness, late work and total Completion times are considered. The following problems are discussed 1. Minimizing a function of two criteria (Tmax+Vmax). 2.Minimizing a function of three criteria of the forms Lex(Tmax+Vmax,Σ■(n@i=1)Ci) and Lex(Σ■(n@i=1)Ci , Tmax+Vmax ). 3. Minimizing a function of two criteria (■(n@i=1)Ti + ■(n@i=1)Vi). For the first problem 1// Tmax+Vmax , a branch and bound algorithm are proposed to find optimal solution . Also, we proved some special cases for this problem which lead to optimal solution. An improved algorithm (A) for Lawler algorithm has been constructed for solving this problem, which leads to an interesting observation that the algorithm (A) will yield optimal solutions in all instances of the test problems. Also computational experience for the (BAB) algorithm is presented. For the second problem which is a generalization of the first problem we use either the SPT rule or modified algorithm (A) to find the best solutions. For the third problem we proposed a (BAB) algorithm with two lower bounds and upper bound which is the minimum of three heuristic methods .We proved some special cases which lead to the optimal solution . We used dominance rules with BAB algorithm to enhance the computational results for this problem

ضغط اشارة البيانات بواسطة معكوس مصفوفة هار ومعكوس تحويل هار == Signal Data Compression by Means of Inverse Haar Matrix and Inverse Haar Transformation

Author name: ريم طالب ميري
Supervisor name: حسين علي حسين
General topic: Mathematics
Specific topic: Mathematics
Degree: Master
University: Mustansiriyah University - College Of Education For Pure Sciences - Department Of Mathematics
Language: English
University location: Baghdad
First pages:
Abstract: ضغط الصورة يتضمن تقليل حجم ملفات الصور مع الاحتفاظ بالمعلومات الضرورية. الضغط هو عملية ضرورية واساسية لتكوين ملفات الصور ذات الحجوم القابلة للنقل. يوجد العديد من طرائق الضغط لكن هذه الرسالة تستخدم ضغط الصور بالاعتماد على معكوس مصفوفة هار ومعكوس مصفوفة التحويل لهار. وفي الطريقة المقترحة يتم ضغط الصورة الرمادية ضغطا بدون ضياع البيانات وضغط الصورة الملونة ضغطا بضياع البيانات ، والهدف من هذا الضغط هو تقليل حجم الصورة وتمثيلها باصغر عدد ممكن من وحدات القياس. بالتالي يمكن ان تسهل نقل ومعالجة الصور. الصورة تحتوي على كميات كبيرة من البيانات عند تنزيلها من الانترنت، (انه يتطلب الكثير من مساحة التخزين، والوقت واتصال انترنت سريع). ويمكن تخفيض عبء العمل هذا اذا تم ضغط البيانات. على سبيل المثال، صورة رمادية من حجم 512 × 512 لديها 262144 عنصر وصورة ملونة من حجم 512 × 512 لديها 786432عنصر للتخزين. عند استخدام اساليب الضغط، يمكننا ان نضغط نقاط الشاشة ، ولكن نوعية صورة ملونة تتاثر قليلا. عندما ينقر على الصورة للتحميل، يتم استدعاء نقاط الشاشة لذاكرة الحاسوب. وقد تم قياس اداء هذه الطريقة باستخدام نسبة قمة الاشارة الى الضوضاء (PSNR)، متوسط مربع الخطا (MSE) ونسبة الضغط (CR). واستخدمنا لقياس جودة الصورة المسترجعة عاملين هما العتبة ونسبة قمة الاشارة الى الضوضاء (PSNR). وتم التطبيق على الصور الملونة والرمادية ذات ابعاد512 ×512 ومن الصور الرمادية بصمة الاصبع والاشعة السينية وجميع الحسابات اجريت باستخدام . MATLAB R2015b | Image compression involves reducing the size of image data files, while retaining necessary information. Compression is a necessary and essential method for creating image files with manageable and transmittable sizes. There have been many types of compression Technique , but this thesis exploits image compression based on inverse Haar matrix and inverse Haar transform matrix. In the proposed method , the grayscale image has been compressed lossless while RGB image has been compressed lossy, the goal of this compression is to reduce size of image and to represent it with the smallest possible number of bits. It can facilitate the transmission and processing of image. An image contains large amounts of data when downloaded from internet, (it requires much storage space, time and fast internet connection). This workload can be reduced if the data is compressed. For instance, a grayscale image of size 512 × 512 has 262144 elements and color image of size 512 × 512 has 786432 elements to store. By using the compression methods, we can compress the pixels , but the color image quality is affected a little. When someone clicks on an image to download, the computer recalls the pixels to the computer memory. The performance of this method has been measured by using Peak Signal to Noise Ratio (PSNR), Mean Square Error (MSE) and Compression Ratio (CR) .The measure of the decompressed image quality is based on two factors ; the threshold and Peak Signal to Noise Ratio (PSNR). Some illustration have been made to justify the proposed approach for gray and color images of size (512× 512) pixels (dimension of the image). Both fingerprint and X - ray have been tested. All programs have been coded using MATLAB R2015b.

محولية النظام لنموذج الاجهاد - القوة لتوزيع لوماك == The system reliability of stress - strength model for a Lomax distribution

Author name: هديل محسن علي
Supervisor name: ندى صباح كرم
General topic: Mathematics
Specific topic: Mathematics
Degree: Master
University: Mustansiriyah University - College Of Education For Pure Sciences - Department Of Mathematics
Language: English
University location: Baghdad
First pages:
Abstract: This research deals with estimations of Reliability system for one component parallel stress - strength system model, two component parallel stress - strength system model with non - identical component parallel which are subjected to a common stress and two component parallel stress - strength system model with non - identical component parallel which are subjected to a two stress, using the Lomax distribution when an unknown shape parameters and scale parameter to be common and known. The practical side was conducted using the method of simulation and comparison study among different estimation methods used in the study and the methods are maximum likelihood, percentile, moment and least squares of the system reliability function, using mean square error and mean absolute error