AL-Rafidain Journal of Computer Sciences and Mathematics

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.

A model of fluid flow with heat transfer by conduction, convection and radiation has been discussed for stability with respect to restricted parameters (k,,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 clear picture of the flow is shown by using an analytical method.

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.

يقال للحلقة R بأنها اثنينية يمنى إذا كان rl(T)=T لكل مثالي أيمن T في R. الهدف من هذا البحث هو تطوير بعض الخواص الأساسية للحلقات الاثنينية، وإيجاد بعض العلاقات التي تربط الحلقات الاثنينية والحلقات المنتظمة والحلقات المنتظمة بقوة.

The main purpose of this paper is to study ERT and MERT rings, in order to study the connection between such rings and II-regular rings.

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].|

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 .

In this paper a class of self-scaling VM-algorithms for unconstrained optimization is investigated. Some theoretical results are given on the scaling strategies that guarantee the global convergence of the new proposed algorithm.

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.

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. Beside 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.