Information Communication Technology and its Influence on Business Education Students Academic Performance in Delta State Tertiary Institutions

This study examined Information and Communication Technology and its influence on Business Education students’ performance among Delta State tertiary institutions. The study was guided by three research questions and three null hypotheses. The study adopted the descriptive survey on a population comprising of nine hundred and thirty-seven (937) respondents from the 2022/2023 academic session of the four (4) public tertiary institutions offering Business Education programme in the state. The sample size for the study was two hundred and ninety-six (296) undergraduate Business Education students. The instrument for data collection was the questionnaire. Data generated were analyzed using the Mean, Standard Deviation and the Pearson Product Moment Correlation Coefficient (PPMCC) for the research questions and formulated null hypotheses. Findings revealed amongst others that ICT facilities are available and at the disposal of Business Education students in Delta State tertiary institutions; that ICT facilities are being utilized by Business Education students in Delta State tertiary institutions; there is a significant correlation between the availability of ICT to Business Education student and its influence on their performance in Delta State tertiary institutions. The study concluded that if ICT is well embraced and sustained across all four Delta State public tertiary institutions sampled for this investigation, it will bring about better learning and enhanced performance; which by extension will facilitate the production of quality Business Education graduates who can be successful in the world of work. The study recommended amongst others that government should consistently make available information and communication technologies in Delta State tertiary institutions and revamp on a regular basis, the already existing ICT infrastructures, as this will help in the consistent use of the facilities for teaching and learning

Asymmetric Squares as Standing Waves in Rayleigh-Benard Convection

Possibility of asymmetric square convection is investigated numerically using a few mode Lorenz-like model for thermal convection in Boussinesq fluids confined between two stress free and conducting flat boundaries. For relatively large value of Rayleigh number, the stationary rolls become unstable and asymmetric squares appear as standing waves at the onset of secondary instability. Asymmetric squares, two dimensional rolls and again asymmetric squares with their corners shifted by half a wavelength form a stable limit cycle.Comment: 8 pages, 7 figure

Wavy stripes and squares in zero P number convection

A simple model to explain numerically observed behaviour of chaotically varying stripes and square patterns in zero Prandtl number convection in Boussinesq fluid is presented. The nonlinear interaction of mutually perpendicular sets of wavy rolls, via higher mode, may lead to a competition between the two sets of wavy rolls. The appearance of square patterns is due to the secondary forward Hopf bifurcation of a set of wavy rolls.Comment: 8 pages and 3 figures, late

Fractal Stability Border in Plane Couette Flow

We study the dynamics of localised perturbations in plane Couette flow with periodic lateral boundary conditions. For small Reynolds number and small amplitude of the initial state the perturbation decays on a viscous time scale $t \propto Re$. For Reynolds number larger than about 200, chaotic transients appear with life times longer than the viscous one. Depending on the type of the perturbation isolated initial conditions with infinite life time appear for Reynolds numbers larger than about 270--320. In this third regime, the life time as a function of Reynolds number and amplitude is fractal. These results suggest that in the transition region the turbulent dynamics is characterised by a chaotic repeller rather than an attractor.Comment: 4 pages, Latex, 4 eps-figures, submitted to Phys. Rev. Le

Convection in colloidal suspensions with particle-concentration-dependent viscosity

The onset of thermal convection in a horizontal layer of a colloidal suspension is investigated in terms of a continuum model for binary-fluid mixtures where the viscosity depends on the local concentration of colloidal particles. With an increasing difference between the viscosity at the warmer and the colder boundary the threshold of convection is reduced in the range of positive values of the separation ratio psi with the onset of stationary convection as well as in the range of negative values of psi with an oscillatory Hopf bifurcation. Additionally the convection rolls are shifted downwards with respect to the center of the horizontal layer for stationary convection (psi>0) and upwards for the Hopf bifurcation (psi<0).Comment: 8 pages, 6 figures, submitted to European Physical Journal

Fault location technique in transmission lines using the minimum square method.

A investiga??o de diferentes tipos de faltas em linhas de transmiss?o ? uma tarefa complexa e de extrema import?ncia para o Sistema El?trico de Pot?ncia (SEP). A modelagem da linha de transmiss?o deve ser estabelecida da forma mais rigorosa poss?vel, visando ? precis?o das dist?ncias de faltas simuladas a partir dos modelos levantados. Neste trabalho ser? modelada uma linha de transmiss?o em circuito simples usando o programa de c?lculo de transit?rios eletromagn?ticos ATPDraw? e, posteriormente, o algoritmo de localiza??o de falta baseado no emprego do m?todo dos m?nimos quadrados ser? implementado no MATLAB?. O desempenho do m?todo ser? discutido em termos de precis?o e robustez dos resultados.The investigation of different types of faults in transmission lines is a complex and extremely important task for the Electric Power System (EPS). The modeling of the transmission line should be established as rigorously as possible, aiming at the accuracy of simulated fault distances from the models surveyed.. In this work, a simple circuit transmission line will be modeled using the ATPDraw? electromagnetic transient program, and later the fault localization algorithm based on the use of the least squares method will be implemented in MATLAB?. The performance of the method will be discussed in terms of accuracy and robustness of the results

Quasiperiodic waves at the onset of zero Prandtl number convection with rotation

We show the possibility of quasiperiodic waves at the onset of thermal convection in a thin horizontal layer of slowly rotating zero-Prandtl number Boussinesq fluid confined between stress-free conducting boundaries. Two independent frequencies emerge due to an interaction between a stationary instability and a self-tuned wavy instability in presence of coriolis force, if Taylor number is raised above a critical value. Constructing a dynamical system for the hydrodynamical problem, the competition between the interacting instabilities is analyzed. The forward bifurcation from the conductive state is self-tuned.Comment: 9 pages of text (LaTex), 5 figures (Jpeg format

Order-of-magnitude speedup for steady states and traveling waves via Stokes preconditioning in Channelflow and Openpipeflow

Steady states and traveling waves play a fundamental role in understanding hydrodynamic problems. Even when unstable, these states provide the bifurcation-theoretic explanation for the origin of the observed states. In turbulent wall-bounded shear flows, these states have been hypothesized to be saddle points organizing the trajectories within a chaotic attractor. These states must be computed with Newton's method or one of its generalizations, since time-integration cannot converge to unstable equilibria. The bottleneck is the solution of linear systems involving the Jacobian of the Navier-Stokes or Boussinesq equations. Originally such computations were carried out by constructing and directly inverting the Jacobian, but this is unfeasible for the matrices arising from three-dimensional hydrodynamic configurations in large domains. A popular method is to seek states that are invariant under numerical time integration. Surprisingly, equilibria may also be found by seeking flows that are invariant under a single very large Backwards-Euler Forwards-Euler timestep. We show that this method, called Stokes preconditioning, is 10 to 50 times faster at computing steady states in plane Couette flow and traveling waves in pipe flow. Moreover, it can be carried out using Channelflow (by Gibson) and Openpipeflow (by Willis) without any changes to these popular spectral codes. We explain the convergence rate as a function of the integration period and Reynolds number by computing the full spectra of the operators corresponding to the Jacobians of both methods.Comment: in Computational Modelling of Bifurcations and Instabilities in Fluid Dynamics, ed. Alexander Gelfgat (Springer, 2018

Trypanosoma cruzi in the chicken model : Chagas-like heart disease in the absence of parasitism

Background: The administration of anti-trypanosome nitroderivatives curtails Trypanosoma cruzi infection in Chagas disease patients, but does not prevent destructive lesions in the heart. This observation suggests that an effective treatment for the disease requires understanding its pathogenesis. Methodology/Principal Findings: To understand the origin of clinical manifestations of the heart disease we used a chicken model system in which infection can be initiated in the egg, but parasite persistence is precluded. T. cruzi inoculation into the air chamber of embryonated chicken eggs generated chicks that retained only the parasite mitochondrial kinetoplast DNA minicircle in their genome after eight days of gestation. Crossbreeding showed that minicircles were transferred vertically via the germ line to chicken progeny. Minicircle integration in coding regions was shown by targeted-primer thermal asymmetric interlaced PCR, and detected by direct genomic analysis. The kDNA-mutated chickens died with arrhythmias, shortness of breath, cyanosis and heart failure. These chickens with cardiomyopathy had rupture of the dystrophin and other genes that regulate cell growth and differentiation. Tissue pathology revealed inflammatory dilated cardiomegaly whereby immune system mononuclear cells lyse parasite-free target heart fibers. The heart cell destruction implicated a thymus-dependent, autoimmune; self-tissue rejection carried out by CD45+, CD8cd+, and CD8a lymphocytes. Conclusions/Significance: These results suggest that genetic alterations resulting from kDNA integration in the host genome lead to autoimmune-mediated destruction of heart tissue in the absence of T. cruzi parasites