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Full issue-- Volume 3 Issue 1, 2020
Get PDFPURSUE: Undergraduate Research Journal
Volume 3 Issue 1, 2020
Article 1 - Harvesting Electrical Energy Produced by Electrogenic Bacteria in Microbial Fuel Cells
Article 2 – The Effects of Fertilizer Rate on the Growth of Egyptian Spinach in a Greenhouse
Article 3 – Exploring the Association Between Nutrition and Mental Health in Adolescence: A Systematic Literature Review
Article 4— Biological Pathways Associated with Wild and Domestic Animal
Basins of Convergence in the Collinear Restricted Four-body Problem with a Repulsive Manev Potential
Get PDFThe Newton-Raphson basins of convergence, related to the equilibrium points, in the collinear restricted four-body problem with repulsive Manev potential are numerically investigated. We monitor the parametric evolution of the position as well as of the stability of the equilibrium points, as a function of the parameter e. The multivariate Newton-Raphson optimal method is used for revealing the basins of convergence, by classifying dense grids of initial conditions in several types of two-dimensional planes. We perform a systematic and thorough analysis in an attempt to understand how the parameter e affects the geometry as well as the basin entropy of the convergence regions. The convergence areas are related with the required number of iterations and also with the corresponding probability distributions
Stokes drag on axially symmetric body in micro polar fluid
Get PDFIn a recent paper, Srivastava et al. (2016) have tested the proposed formula based on DS-conjecture Datta and Srivastava, (1999) of Stokes drag on axially symmetric bodies placed under micropolar fluid to improve the drag value under Oseen’s limit. In the present work, proof of the proposed drag formula is given for both axial and transverse Stokes flow of micropolar fluid under certain body geometry constraints mainly of continuously turning tangent on body curve in meridional plane as assumed in DS-conjecture. The general expression of drag immediately reduces to the value of drag in classical Newtonian fluid as micro polarity parameter k approaches to zero. The proposed expressions of Stokes drag are applied to various axially symmetric bodies like sphere, spheroid, deformed sphere, cycloidal body, Cassini body, Hypocycloidal body and egg-shaped body and results are in agreement with some known values available in the literature in the limiting cases
MHD Mixed Convective Flow of Maxwell Nanofluid Past a Porous Vertical Stretching Sheet in Presence of Chemical Reaction
Get PDFIn this study, MHD mixed convective flow of Maxwell nanofluid past a porous vertical stretching sheet in the presence of chemical reaction is investigated. The governing partial differential equations with the corresponding boundary conditions are reduced to a set of ordinary differential equations via Lie group analysis. Numerical solutions of these equations are obtained by Runge-Kutta fourth order method along with shooting technique and the results obtained for different governing flow parameters are drawn graphically and their effects on velocity, temperature and concentration profiles are discussed. The values of skin-friction coefficient, Nusselt number coefficient and Sherwood number coefficient are presented in table. A comparison with previously reported data is made and an excellent agreement is noted
Modeling and Analysis of the Impact of Vocational Education on the Unemployment Rate in Nigeria
Get PDFUnemployment is a major determinant of a weak economy and a good measure of living standard in a country. Nigeria is faced with the problem of unemployment at present. By that, a mathematical model is formulated to investigate the effect of vocational education on the unemployment challenges in Nigeria. The model is tested for the basic requirements of a good mathematical model. The equilibrium analysis of the model is conducted and both the unemployment-free and the unemployment endemic equilibria are obtained. The threshold for the implementation success of the vocational education program is also derived following the approach of epidemic models. Stability analysis of the unemployment-free equilibrium is performed via the stability theory of nonlinear differential equations. Numerical simulation is carried out using parameter values from published data as well as assumption. The result of the simulation shows that the current unemployment rate in Nigeria is going to the peak unless vocational education is revived and makes to function
Generalized Fractional Calculus Operators Involving the Product Of the Jacobi Type Orthogonal Polynomials And Multivariable Polynomials
Get PDFThe objective of this paper is to establish four theorems for the Marichev-Saigo-Maeda fractional integration and differentiation formula to the product of the finite classes of the classical orthogonal polynomials with the general class of multivariable polynomials. The results are presented in terms of the Wright generalized hypergeometric function. Corresponding assertions in terms of Saigo, Erdelyi-Kober and Riemann-Liouville type of fractional integrals are also presented. Further, we point out also their relevance
Mathematical Modeling for Studying the Sustainability of Plants Subject to the Stress of Two Distinct Herbivores
Get PDFViability of plants, especially endangered species, are usually affected by multiple stressors, including insects, herbivores, environmental factors and other plant species. We present new mathematical models, based on systems of ordinary differential equations, of two distinct herbivore species feeding (two stressors) on the same plant species. The new feature is the explicit functional form modeling the simultaneous feedback interactions (synergistic or additive or antagonistic) between the three species in the ecosystem. The goal is to investigate whether the coexistence of the plant and both herbivore species is possible (a sustainable system) and under which conditions sustainability is feasible. Our theoretical analysis of the novel model without including competitions among the two herbivores reveals that the number of equilibrium states and their local stability depends on the type of interaction between the stressors: synergistic or additive or antagonistic. Our numerical results, based on value of parameters available, suggest that a sustainable system requires significant herbivore inter- or intra-species competition or both types. Additionally, our numerical findings indicate that competition and interaction of additive type promotes coexistence equilibrium states with the highest plant biomass. Furthermore, the system can exhibit periodic behavior and show the potential for multi-stability
Exploring the Convergence Properties of a New Modified Newton-Raphson Root Method
Get PDFWe examine the convergence properties of a modified Newton-Raphson root method, by using a simple complex polynomial equation, as a test example. In particular, we numerically investigate how a parameter, entering the iterative scheme, affects the efficiency and the speed of the method. Color-coded polynomiographs are deployed for presenting the regions of convergence, as well as the fractality degree of the complex plane. We demonstrate that the behavior of the modified Newton-Raphson method is correlated with the numerical value of the parameter 1. Additionally, there are cases for which the method works flawlessly, while in some other cases we encounter the phenomena of ill-convergence or even non-convergence
A uniformly charged circular disk with an anisotropic Coulomb interaction potential
No full textWe consider a uniformly charged circular disk containing elementary charges that interact with an anisotropic Coulomb interaction potential. Such an anisotropic Coulomb interaction potential has been recently considered within the framework of a two-dimensional system of electrons in the quantum Hall regime. The anisotropy of the potential is introduced by a phenomenological parameter that can be tuned continuously as to incorporate the standard isotropic Coulomb interaction potential as a special case. The energy of the uniformly charged circular disk is calculated exactly for the given anisotropic interaction potential as a function of the anisotropy parameter. The results obtained are related to electrostatic problems that involve uniformly charged flat elliptical plates and may be useful to understand finite two-dimensional systems of electrons in the quantum Hall regime in which all point charges interact with the anisotropic Coulomb interaction potential presently considered
Gender differences in the interaction effect of community resources and attitudes toward seeking professional help on posttraumatic stress, depression, and posttraumatic growth
No full textThe current study examined the gender differences in the interaction effect of community resources and attitudes toward seeking professional help in predicting posttraumatic stress, depression, and posttraumatic growth for female and male survivors of Hurricane Harvey. Participants were 413 adults who reported directly experiencing Hurricane Harvey, which made landfall on August 26, 2017. Purposive sampling was used to recruit participants approximately 16 months after the hurricane via an online survey. Among men, significant interaction effects of community resources and attitudes toward seeking help on posttraumatic stress, depression, and posttraumatic growth were found even after statistically controlling for age, educational attainment, income, marital status, and racial minority status. Among women, no interaction effects were found. Women with open attitudes toward seeking psychological treatment experienced higher posttraumatic stress and posttraumatic growth, and higher resources were positively associated with growth. The current study raises important implications on gender differences on community resources and attitudes toward seeking professional help after a hurricane