870 research outputs found
Egyptian electronic government: The university enrolment case study
E-government projects have potential for greaterefficiency and effectiveness of
government operations. For thisreason, many developing countries governments
have investedheavily in this agenda and an increasing number of e-
governmentprojects are being implemented. However, there is a lack of clearcase
material, which describes the potentialities and consequenceexperienced by
organizations trying to manage with this change. TheMinistry of State for
Administrative Development (MSAD) is theorganization responsible for the e-
Government program in Egyptsince early 2004. This paper presents a case study of
the process ofadmission to public universities and institutions in Egypt which
is ledby MSAD. Underlining the key benefits resulting from the
initiative,explaining the strategies and the development steps used toimplement
it, and highlighting the main obstacles encountered andhow they were overcome
will help repeat the experience in otheruseful e-government
projects.Keywords—Case studies, Egypt, Electro
Random Walk Model on a Hyper-Spherical Lattice
We use a one-dimensional random walk on -dimensional hyper-spheres to
determine the critical behavior of statistical systems in hyper-spherical
geometries. First, we demonstrate the properties of such walk by studying the
phase diagram of a percolation problem. We find a line of second and first
order phase transitions separated by a tricritical point. Then, we analyze the
adsorption-desorption transition for a polymer growing near the attractive
boundary of a cylindrical cell membrane. We find that the fraction of adsorbed
monomers on the boundary vanishes exponentially when the adsorption energy
decreases towards its critical value. We observe a crossover phenomenon to an
area of linear growth at energies of the order of the inverse cell radius.Comment: to appear in NPB Proc. Suppl. of LATTICE'94, 3 pages, ps-file
uuencoded, 2 figures included, NO-NUM-
Phase diagram of a dilute ferromagnet model with antiferromagnetic next-nearest-neighbor interactions
We have studied the spin ordering of a dilute classical Heisenberg model with
spin concentration , and with ferromagnetic nearest-neighbor interaction
and antiferromagnetic next-nearest-neighbor interaction . Magnetic
phases at absolute zero temperature are determined examining the
stiffness of the ground state, and those at finite temperatures are
determined calculating the Binder parameter and the spin correlation
length . Three ordered phases appear in the phase diagram: (i) the
ferromagnetic (FM) phase; (ii) the spin glass (SG) phase; and (iii) the mixed
(M) phase of the FM and the SG. Near below the ferromagnetic threshold , a reentrant SG transition occurs. That is, as the temperature is decreased
from a high temperature, the FM phase, the M phase and the SG phase appear
successively. The magnetization which grows in the FM phase disappears in the
SG phase. The SG phase is suggested to be characterized by ferromagnetic
clusters. We conclude, hence, that this model could reproduce experimental
phase diagrams of dilute ferromagnets FeAu and EuSrS.Comment: 9 pages, 23 figure
Simple Asymmetric Exclusion Model and Lattice Paths: Bijections and Involutions
We study the combinatorics of the change of basis of three representations of
the stationary state algebra of the two parameter simple asymmetric exclusion
process. Each of the representations considered correspond to a different set
of weighted lattice paths which, when summed over, give the stationary state
probability distribution. We show that all three sets of paths are
combinatorially related via sequences of bijections and sign reversing
involutions.Comment: 28 page
Critical frontier of the Potts and percolation models in triangular-type and kagome-type lattices I: Closed-form expressions
We consider the Potts model and the related bond, site, and mixed site-bond
percolation problems on triangular-type and kagome-type lattices, and derive
closed-form expressions for the critical frontier. For triangular-type lattices
the critical frontier is known, usually derived from a duality consideration in
conjunction with the assumption of a unique transition. Our analysis, however,
is rigorous and based on an established result without the need of a uniqueness
assumption, thus firmly establishing all derived results. For kagome-type
lattices the exact critical frontier is not known. We derive a closed-form
expression for the Potts critical frontier by making use of a homogeneity
assumption. The closed-form expression is new, and we apply it to a host of
problems including site, bond, and mixed site-bond percolation on various
lattices. It yields exact thresholds for site percolation on kagome, martini,
and other lattices, and is highly accurate numerically in other applications
when compared to numerical determination.Comment: 22 pages, 13 figure
Precise calculation of the threshold of various directed percolation models on a square lattice
Using Monte Carlo simulations on different system sizes we determine with
high precision the critical thresholds of two families of directed percolation
models on a square lattice. The thresholds decrease exponentially with the
degree of connectivity. We conjecture that decays exactly as the
inverse of the coodination number.Comment: 2 pages, 2 figures and 1 tabl
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