ISSN: 1815-4816

Volume 1, Issue 1

Volume 1, Issue 1, Spring 2004, Page 7-146


Stability Analysis for Fluid Flow between Two Infinite Parallel Plates I

Mahdi F. Mosa; Abdo M. Ali

AL-Rafidain Journal of Computer Sciences and Mathematics, Volume 1, Issue 1, Pages 8-19
DOI: 10.33899/csmj.2004.164093

                A model of fluid flow with heat transfer by conduction, convection and radiation has been discussed for stability with respect to restricted parameters (k,a,r,T*) which are proportional to: wave numbers, thermal expansion coefficient, combination of many numbers (Re,Pr,Ec,Bo,W,) and the ratio of walls temperatures, respectively using numerical technique which illustrate that the stability of the system depends on the parameters T* and a.
A clear picture of the flow is shown by using an analytical method.
 

On Dual Rings

Nazar H. Shuker; Rani S. Younis

AL-Rafidain Journal of Computer Sciences and Mathematics, Volume 1, Issue 1, Pages 20-26
DOI: 10.33899/csmj.2004.164094

A ring R is called a right dual ring if rl(T) = T  for all right ideals T of R. The main  purpose of this  paper is to develop some basic properties of dual rings and to give the connection between dual rings, regular rings and strongly regular rings.
 

In Accurate CG-Algorithm for Unconstrained Optimization Problems

Nidhal Al-Assady; Maysoon M. Aziz; Ban Ahmed Mitras

AL-Rafidain Journal of Computer Sciences and Mathematics, Volume 1, Issue 1, Pages 34-53
DOI: 10.33899/csmj.2004.164096

An algorithm for unconstrained minimization is proposed which is invariant to a non-linear scaling of a strictly convex quadratic function and which generates mutually conjugate directions for extended quadratic function. It is derived for inexact line searches and is designed for general use, it compares favorably numerical tests [over eight test functions and dimensionally up to (2-100) with the H/S, DX, F/R, P/R, and A/B algorithms on which this new algorithm is based.
 

FID Fast Image Display for (.BMP & .PCX) Images

Rawaa P. Qasha; Ahmed S. Nori

AL-Rafidain Journal of Computer Sciences and Mathematics, Volume 1, Issue 1, Pages 66-87
DOI: 10.33899/csmj.2004.164098

Video display speed constitutes a very important factor in modern software performance. The best way to achieve fastest display is by accessing Video RAM and programming video card directly. In addition to the speed, this method provides flexibility and high performance video display operations. Besides that, dealing with 64K and 16.7 M color mode can be achieved only by this method.
Fast Image Display (FID) software is developed to display two popular types of images (BMP, PCX) using direct access to VRAM method with various SVGA modes differing in resolutions and number of colors. Assembly instructions and C++ language have been used to write Software parts.
 

Rings in which Every Simple Right R-Module is Flat

Raida D. Mahmood

AL-Rafidain Journal of Computer Sciences and Mathematics, Volume 1, Issue 1, Pages 88-95
DOI: 10.33899/csmj.2004.164099

The objective of this paper is to initiate the study of rings in which each simple right R-module is flat, such rings will be called right SF-rings. Some important properties of right SF-rings are obtained. Among other results we prove that: If R is a semi prime ERT right SF-ring with zero socle, then R is a strongly regular ring.
 

Fast Backpropagation Neural Network for VQ-Image Compression

Basil S. Mahmood; Omaima N. AL-Allaf

AL-Rafidain Journal of Computer Sciences and Mathematics, Volume 1, Issue 1, Pages 96-118
DOI: 10.33899/csmj.2004.164100

The problem inherent to any digital image is the large amount of bandwidth required for transmission or storage. This has driven the research area of image compression to develop algorithms that compress images to lower data rates with better quality.  Artificial neural networks are becoming very attractive in image processing where high computational performance and parallel architectures are required.
       In this work, a three layered backpropagation neural network (BPNN) is designed to compress images using vector quantization technique (VQ).The results coming out from the hidden layer represent the codebook used in vector quantization, therefore this is a new method to generate VQ-codebook. Fast algorithm for backpropagation called









 





 



(FBP) is built and tested on the designed BPNN. Results show that for the same compression ratio and signal to noise ratio as compared with the ordinary backpropagation algorithm, FBP can speed up the neural system by more than 50. This system is used for both compression/decompression  of any image. The fast backpropagation (FBP) neural network algorithm was used for  training  the designed BPNN. The efficiency of the designed BPNN comes from reducing the chance of error occurring during the compressed image transmission through analog channel (BPNN can be used for enhancing any noisy compressed image that had already been corrupted during transmission through analog channel). The simulation of the BPNN image compression system is  performed using the Borland C++ Ver 3.5 programming language. The compression system has been applied on the well known images such as Lena, Carena, and Car images, and also deals with BMP graphic format images.
 
 

A Modified Heuristic Procedure for NP-Complete Problems Supported by Genetic Algorithms

Najla Akram Al-Saati

AL-Rafidain Journal of Computer Sciences and Mathematics, Volume 1, Issue 1, Pages 120-137
DOI: 10.33899/csmj.2004.164101

This work is based on the process of modifying an intelligent heuristic rule used in solving NP-Complete problems, where a study and a modification of a Flow Shop assignment heuristic has been carried out to solve a well-known classic Artificial Intelligent problem, which is the traveling Salesman problem. For this modification to be carried out successfully, the problem’s mathematical formulation had to be studied carefully and the possibility of reformulating the problem to be more suitable for the heuristic procedure. This may require some changes in the heuristic procedure itself, these adjustments were due to the noticeable differences like the symmetric property present in the traveling salesman problem environment and some other differences.
Genetic Algorithm is added to improve the results obtained by the used heuristic, where the use of crossover and mutation procedures will provide better chances for the near optimal solution to be improved towards optimal solutions.
The test problem is made on cities that lie on the regular square grid, which simplify the calculations of distance traveled between any two cities. Programs were written using C programming language, and timers were used to measure the elapsed time of calculations in order to assess the efficiency of the program.
 

The Order of Accuracy for SOR Waveform-Relaxation Method for Solving ODEs

Ann J. H. Sawoor

AL-Rafidain Journal of Computer Sciences and Mathematics, Volume 1, Issue 1, Pages 138-146
DOI: 10.33899/csmj.2004.164102

In this paper we will discuss and find the order of accuracy for subsystems of ODE that obtained from partitioning the successive Over relaxation(SOR) method and we will show that the form of equation to
be solved after applying the waveform relaxation scheme is :
 
Where  ω ,the relaxation parameter ,should be chosen so that  the  rate of convergence is maximized .
 
 

Existence Of (47,5)- Arcs in The Projective Plane PG (2,13).

Shuaa Mahmood Aziz

AL-Rafidain Journal of Computer Sciences and Mathematics, Volume 1, Issue 1, Pages 7-15
DOI: 10.33899/csmj.2004.164103

In this work we show the existence of complete (47,5)- arcs which are unknown until now. The upper bound for the  
(k,5)- arcs is narrowed in the finite projective plane PG (2,13). The narrowing is fulfilled by finding complete (47,5)-arcs which are 372 arcs. However, only one (47,5)-complete arc out of the 372 is considered in this work. Furthermore the relation between complete (k, n)-arcs and minimal t-blocking sets is proved, in addition to between the connection of our arc and the code.
 

Data Object Modeling for Depreciation System Using UML

Asmaa Yaseen Hammo; Alaa F. Saeed

AL-Rafidain Journal of Computer Sciences and Mathematics, Volume 1, Issue 1, Pages 17-37
DOI: 10.33899/csmj.2004.164104

Data object modeling is considered the most effective style in data manipulation. This style provides the ability to decompose complex systems into parts, these parts can be manipulated simply, understanding, accuracy with easy updating reducing run time errors supporting ability of design languages such as Unified Modeling Language UML. The research implements modeling of Depreciation system using UML and its tools such as (objects, classes, link & association & aggregation, generalization, drive data, class diagram, packages, logical horizon) and obtaining the general schema for classes to be converted to an used application using data base programming language.
 

A Study on the Application of Henon with a Case Study of Ecology

Basil Y.Th. Al-Khayat; Inaam H. Abd

AL-Rafidain Journal of Computer Sciences and Mathematics, Volume 1, Issue 1, Pages 39-57
DOI: 10.33899/csmj.2004.164105

This paper deals with the well known Henon map. Its main properties are studied as well as a non deterministic form. Least squares estimates of parameters of the non deterministic model are driven and a case study from animal ecology is studied, where the population size of the Canadian lynx animal is considered as a time series. The embedding dimension of this time series is estimated and then a mathematical model of the form of suggested non deterministic (stochastic) model is fitted . The chaotic property of this series is studied throughout the fitted model.        
 

Estimation of Double Smoothing Parameters with Simulation

Fadel A. Al-Taie

AL-Rafidain Journal of Computer Sciences and Mathematics, Volume 1, Issue 1, Pages 59-74
DOI: 10.33899/csmj.2004.164106

In this paper we estimate that the equation of smoothing to the first Smoothing is the same equation of double exponentioal smoothing, and finding the equation of prediction of two state first: the variance of the original time cerise  xt ,( σ2xt )is the same as the variance of  the Ft, , (σ2Ft), ( σ2xt=, σ2Ft), and the second state the variance of xt , , (σ2xt)is not the same as the variance of Ft , σ2ft , ( σ2xt=, σ2Ft),. Ft
This results will be applied to the real data which represent the mean of relative wet of Mosul city, and also to the data obtained form simulation, with use the (χ2 , MSD) to select the best of smoothing.