AL-Rafidain Journal of Computer Sciences and Mathematics

New hyperbolic model different from the quadratic ones is proposed for solving unconstrained optimization problems which modify the classical conjugate gradient method. This new model was compared with established methods over a variety of standard non-linear test functions. The numerical results show that the use of non-quadratic model is beneficial in most of the problems considered especially when the dimensional of the problems increases.
 

A non-linear parabolic system is derived to describe compressible nuclear waste disposal contamination in porous media . Galerkin method is applied for the pressure equation . For the concentration of the brine of the fluid, a kind of partial upwind finite element scheme is constructed. A numerical application is included to demonstrate certain aspects of the theory and illustrate the capabilities of the kind of partial upwind finite element approach.
 

A ring R is said to be right(left) sp-weakly regular if for each a Î R and a positive integer n,  aΠ aR aR (aÎ R aR a). In this paper, we continue to study sp-weakly regular rings due to R. D. Mahmood and A. M. Abdul-Jabbar [8]. We first consider properties and basic extensions of sp-weakly regular rings, and we give the connection of sp-weakly regular, semi  p-regular and p-biregular rings.
 
 

We solved φ⁴ Klein-Gordon equation numerically by using two finite difference methods: The first is the explicit method and the second is the implicit (Crank-Nicholson) method. Also, we studied the numerical stability of the two methods using Fourier (Von Neumann) method and it has been found that the first method is simpler and has faster convergence while the second method is more accurate, and the explicit method is conditionally stable while the implicit method is unconditionally stable.
 

In this Paper, we studied the stability analysis of steady state solutions of Gray-Scott Model in one-dimension using Fourier mode and we showed that the solutions are conditionally stable.
 

The generalized envelopes are studied by a given nonstandard definition of envelope of a family of lines defined in a projective homogenous coordinates PHC by: u(t)x + v(t)y + w(t)z = 0. The new nonstandard concepts of envelope are applied to conic sections. Our goal in this paper is hat for a given conic section curve f(x,y)=0, we search for the family of lines in which  f  is its envelope.
   
 

In the present paper, the problem of defining continuity and s-continuity as a galaxy of hyperreal function is discussed. Our attempt is based on the fact that monads are subsets of some galaxies. New results are obtained, with nonstandard variables, related to a new extension of the continuity notion.
 

A new restarting criterion for FR-CG method is derived and investigated in this paper. This criterion is globally convergent whenever the line search fulfills the Wolfe conditions. Our numerical tests and comparisons with the standard FR-CG method for large-scale unconstrained optimization are given, showining significantly improvements.
 

In this work a new data hiding algorithm for binary images is used. In this algorithm the pixels which can be flipped without introducing noticeable artifacts are identified at first by using some rules that examine the neighbors of the central pixels in each non-uniform block and then this central pixel only is changed in the block which matches these rules and this property allows easy detection of the embedded data without referring to the original   image. Experiments show different results for different binary images. The program is written  in MATLAB (6.5).
 

SQL Optimization is the process of choosing the most efficient way to execute SQL such  as Data manipulation language  (Select, Insert, Update, Delete). Relational model represents the object through the use of relations; on the other hand the main aim of ORDBMS model is to represent the special characteristics of OOP. The first model deals with the Relation & Correlated sub queries, while the second one uses collection types (Object type, Varrays, Nested table). Explain plane is used to examine exactly how oracle execute SQL statements “ oracle SQL analyze” provides a facility for easily generate any  explain plan . DML language (SQL) as tools for any comparison can be achieved by the statistical performance parameter (Elapsed time, CPU time, Logical block read, Physical block read …). Statistical analysis using ANOVA TABLE is used to judge between comparisons. We found that nested table was the most effective type of data, the object type was the least effective (consume lowest time of execution). We also found that increasing data size will increase any of performance data parameter until we reach size of 40% the time begins to decrease. It is found that SELECT, UPDATE and DELETE have the most influence on the performance parameter, respectively.
 

This research presents the fundamental concepts of tabu search for   optimization problem as symmetric traveling salesman problem. The purpose of this research is to solve the traveling salesman problem with tabu search method, to find an optimal solution of small search space and computational requirements. 
 

Fuzzy logic is a branch of artificial intelligence techniques, it deals with uncertainty in knowledge that simulates human reasoning in incomplete or fuzzy data. Fuzzy relational inference that was applied in medical diagnosis was used within the medical knowledge base system to deal with diagnostic activity, treatment recommendation and patient's administration.
In this research, a medical fuzzy expert system named (PedFES) has been developed for diagnosis and decision making of general pediatrics diseases.
The (PedFES) is a rule based fuzzy expert system, the results of laboratory analysis are inserted into the system. This system can define the probable diagnosis depending on these data, and later on it can pick out the most probable one for disease.
 

In this search,  we develop the nonlinear constrained optimization by investigation a new region of solution depending on extended conic model to non-conic model by using conjugate gradient method. The new method is too effective when compared with other established algorithms to solve standard constrained optimization problems it performance from evaluations were the number of function (NOF),number of iteration (NOI) and  the number of constrained (NOC).
 

Iris recognition is regarded as the most reliable and accurate biometric identification system available. The work presented in this paper involves improving iris segmentation to reduce execution time. To determine the performance of the iris system two databases of digitized grayscale eye images are used.
The segmentation process in the iris recognition system is used to localize the circular iris and pupil regions, excluding eyelids and eyelashes. New techniques are proposed and implemented for pupil detection. These techniques are mask, profile and the combined profile mask (CPM) technique. The extracted iris region is normalized into a rectangular block with constant dimensions to account for imaging inconsistencies.
The feature extraction technique is based on 2D Gabor filters. The Hamming distance is used to classify the iris templates, and the FAR, FRR and RR are calculated. 
The results of the study proved that the best technique for pupil detection is when using the combined technique. It gives about 100% success rate for pupil detection.
 

The main purpose of this paper is to study CS-rings. We give some properties of right CS-rings and the connection between such rings and reduced rings, regular rings, strongly regular rings, and S-weakly regular rings.
 

Our purpose in this research is the development of higher order Runge-Kutta methods for solving stiff systems. We have developed methods of order five, six, and seven. We studied their stability Region and applications for solving stiff systems. Then we developed the corresponding implicit forms of these methods and we analyzed their stability and implementation for solving stiff systems.
 
 

It is not easy to find the Wiener polynomials for generalized distance of  compound graphs constructed in the form and  for any two disjoint connected graphs and .Therefore, in this paper, we obtain Wiener polynomials for generalized distance of and  when and  are special graphs such as complete graphs, and stars. The Wiener index of each such graph with respect to the generalized distance is also obtained in this paper.
            The Wiener polynomial for the generalized distance of the join of any two disjoint connected graphs is also obtained in this paper.
 

The purpose of this paper is to study the crossed modules and crossed homomonphisms, and since these concepts are related to the group actions on groups we presented these types of actions.
 

The aim of the project is to develop parallel approaches for Gaussian Elimination Methods that are used in linear programming  to solve linear module  systems.
            Most of these models are time-consuming when executed and processed in the sequential microprocessor computers. During the project, we try to decrease this time and increase the efficiency of the algorithm for the Gaussian Elimination Method, through developing parallel methods appropriate to be executed on MIMD type computers.
            In this paper, three algorithms were suggested for paralleling a developed algorithm of Gaussian Elimination Method and a comparison was made between the three algorithms and the original.
            As we have been able to accelerate the three parallel methods and the speedup was one of the following:
          Speedup =  ,  no. of processor is (50)
            In general, the practical results and the suggested programs for these new algorithms proved to be better in performance than their analogues that are executed in computers of sequential processor in view of the two elements of execution time and algorithm time.
 

Clustering is a mostly unsupervised procedure and the majority of the clustering algorithms depend on certain assumptions in order to define the subgroups present in a data set. As a consequence, in most applications the resulting clustering scheme requires some sort of evaluation as regards its validity.
            In this paper, we present a clustering validity procedure, which evaluates the results of clustering algorithms on data sets. We define a validity indexes, S_Dbw & SD, based on well-defined clustering criteria enabling the selection of the optimal input parameters values for a clustering algorithm that result in the best partitioning of a data set.
            We evaluate the reliability of our indexes experimentally, considering clustering algorithm (K_Means) on real data sets.
Our approach is performed favorably in finding the correct number of clusters fitting a data set.
 

In this paper we study the stability of time series models in general, and for some non-linear time series models as a special case. Lagrange method to find the stability of non-linear models has been given.
            The Leishmaniasis time series was studied and modeled by different non-linear models such as, seasonal ARIMA model by using the logarithmic transformation, exponential model of order two and the polynomial model. The stability of all such models by the above method has been obtained. From the comparison we find that the SARIMA is the best among all such models which we used for forecasting one year ago.
 

, be the w- width ,   Let G be a k₀-connected graph, and let the distance between the two vertices  u,v  in G. The w-Wiener polynomial of the width distance of G is defined by:
 
 
                                    The w-Wiener polynomials of the Cartesian product of K₂with Complete graphK_p, Star S_p, Complete bipartite graph K_r,s and path  P_{r ,} are obtained in this paper. The diameter with respect to the width distance-w, and the Wiener index for each such graphs are also obtained.
 

Modern digital camera technology has produced huge services for the users from different ages and specifications .It made it easer to have images, but the user still needs to enhance those images, which have some problems when taken by the camera, for not applying enough light, as taking it in cloudy weather or on bright light or dark area or taking it from a far distance, all these reasons make the picture not clear having ambiguous details and colors. So, through this research we used some image contrast enhancement techniques to adjust the light for dark images, to make them have deep detail, sharp edges and better quality. Contrast problem is one of the most problems that face those who work on research field or normal users.
            The aim of this research is to improve the contrast of images that have bad contrast using both classical techniques and intelligence techniques. Among intelligence techniques we chose the fuzzy logic methods, to have images contain better colors all over the image and make the images look brighter. By studying the classical and fuzzy logic methods, we proposed a method named (Fuzzy Hyperbolic Threshold), the proposed method gave very good results. We applied the methods on gray, colored images and on a video, and used (Matlab 7) to implement those methods.
 

This research aims at designing Fuzzy model for applying the Linear Method for Enhancing the Edges of the Satellite Images. The researcher depended on some information about the satellite image like (brightness value, gray level, lines…etc) and connect them with the fuzzy logic for producing fuzzy system dealing with the contents of the satellite image.
            The fuzzy system designed by scaling the two inputs (Brightness Value) and (Gray Level) and producing single output (Result B.V.), and it is built with (4 rules) that evaluate the performance of the system. The system was programmed by (Matlab 7) and works under WindowsXP.