Univesity of Thi-Qar Journal

The ground-state phase diagram and phase diagrams in the temperature-anisotropy
plane of a ferrimagetic mixed spin SA
j=3/2 and spin SB
j=5/2 Ising system are investigated by
the use of the mean-field theory. Some interesting features are found in the temperature
dependences of sublattice magnetizations on a square lattice.
Keywords: Mixed-spin Ising model ;Ferrimagnet; single-ion anisotropy; second-order
phase transition.

The pseudo-random early in cryptography systems, the important of cellular
automata has properties which are considered a state machine, high periods.
two–dimensional cellular automata was used to avoid the limitation of the generated
periods in the pseudo-random binary sequences such that used in linear shift Feedback
registers (LFSR) , the binary sequences that are generated form CA generator are
characterized by their success in random tests.

Akram[2006] introduced the concept of contractible class. He proved that the classes
of Hamiltonian and 3-connected graphs as well as the class of trees are contractible classes.
Further he introduced the concept of contractibility number and characterized regular
graphs having contractibility number less equal two. In this work we characterized bipartite
graphs having contractibility number less equal two

Salt gradient solar ponds are large area, low cost devices for collection solar
energy and storing it in the water as thermal energy. High salinity is maintained in the
bottom layers of the pond and low salinity in the upper layers. The lower layers containing
uniformly distributed brine is known as the lower convective zone (LCZ) or storage zone,
and the upper layer which contains varying brine concentrations, which increases with the
depth, is known as the gradient zone, or non-convective zone(NCZ), whereas the upper
layer is thin and called the upper convective zone (UCZ). The incident solar radiation
penetrating the pond warms the bottom layer of water. Because of its high relative
density (due to its salt content), this hot water cannot rise to the low-salinity layers, thus
heat is stored at the bottom. This stored energy can be removed by means of heat
exchange system. This solar-heated water can be used to supply industrial process heat, or
to operate heat engines using low boiling point fluids which flow into turbines to generate
electrical power, also in space heating, water distillation.

The aim of this paper is to classify the different human face images in specific clusters
such that the different face images for any given person will be compiled in one cluster,
whereas the different face images of other persons will be set in other clusters. For each
person at least five different face images are taken by choosing different rotation angles.
We proposed three algorithms, the first algorithm used to determine the adaptive
neighborhood for each individual, the second one used to prepare the data of the studied
population before the implementations, and the third is an automatic clustering
algorithm. Our proposed algorithms were applied on different face images of many
persons which were taken from the Iraqi population and the ORL database of many
persons. We obtained a good classification results with small rate of error. This research
is implemented by using Pentium (4) PC and MATLAB 6.5.