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Discovering design implications of public housing adjustment benefits in Nigeria
No full textHeterogeneous spatial paradigm in public housing design is essentially inevitable and most avidly followed urban issue in Nigeria today. In contrast to the one time homogenous configuration provided which has proved ineffective overtime, layout patterns and benefits of transformation are less focused on. Equally, design solutions emerging from transformation benefits have limited empirical footing. In this circumstance, houses of urban public housing typology were studied after transformation. The study adopted conditional sampling of 42 public housings in five states of northern Nigeria. Social pattern analysis was used to assess the social pattern of the transformed spatial configurations, subjected to gamma analysis in establishing the spatial pattern of adjustments. The resultant graphical delineation indicated that the spatial system developed of out of the social meaning imposed upon it by the social activities of the occupants. Thus, design implication requires developers to consider future transformation initiatives of occupants at the design stage
Use of Cubic B-Spline in Approximating Solutions of Boundary Value Problems
Get PDFHere we investigate the use of cubic B-spline functions in solving boundary value problems. First, we derive the linear, quadratic, and cubic B-spline functions. Then we use the cubic B-spline functions to solve second order linear boundary value problems. We consider constant coefficient and variable coefficient cases with non-homogeneous boundary conditions for ordinary differential equations. We also use this numerical method for the space variable to obtain solutions for second order linear partial differential equations. Numerical results for various cases are presented and compared with exact solutions
Hydromagnetic Flow and Heat Transfer of Eyring-Powell Fluid over an Oscillatory Stretching Sheet with Thermal Radiation
Get PDFAn analysis is carried out to investigate the magnetohydrodynamic flow and heat transfer in an unsteady flow of Eyring-Powell fluid over an oscillatory stretching surface. The radiation effects are also considered in energy equation. The flow is induced due to infinite elastic sheet which is stretched periodically back and forth in its own plane. Finite difference scheme is used to solve dimensionless partial differential equations. The effects of emerging parameters on both velocity and temperature profiles are illustrated through graphs. The results obtained by means of finite difference scheme are compared with earlier studies and found in excellent agreement
Boundary-Layer Flow of Nanofluids over a Moving Surface in the Presence of Thermal Radiation, Viscous Dissipation and Chemical Reaction
Get PDFThe flow problem presented in the paper is boundary-layer flow of nanofluids over a moving surface in the presence of thermal radiation, viscous dissipation and chemical reaction. The plate is assumed to move in the same or opposite direction to the free stream which depends on the sign of the velocity parameter. The partial differential equations appearing in the governing equations are transformed into a couple of nonlinear ordinary differential equations using similarity transformations. The transformed equations in turn are solved numerically by the shooting method along with the fourth order Runge-Kutta integration technique. Influences of the pertinent parameters in the flow field are exhaustively studied and sequentially explained graphically and in tabular form. For selected values of the parameters involved in the governing equations like Lewis number, the velocity parameter, magnetic parameter, Eckert number Brownian motion parameter, thermophoresis parameter, thermal radiation parameter, Prandtl number, Reynolds number and chemical reaction parameter, numerical results for the velocity field, temperature distribution, concentration, skin friction coefficient, Nusselt number and Sherwood number are obtained. The results are analyzed and compared with previously published works; they are found in excellent agreement
Thermal Instability in a Horizontal Layer of Walter’s (Model B\u27) Visco-Elastic Nanofluid- A More Realistic Approach
Get PDFThermal instability in a horizontal layer of Walter’s (Model B\u27) visco-elastic nanofluid is investigated for more realistic boundary conditions. The flux of volume fraction of nanoparticles is taken to be zero on the isothermal boundaries. The model used for nanofluid incorporates the effect of Brownian diffusion and thermophoresis. Perturbation method, normal mode technique and Galerkin method are used in the solution of the eigenvalue problem. Oscillatory convection has been ruled out for the problem under consideration. The influences of the Lewis number, modified diffusivity ratio and nanoparticle Rayleigh number on the stationary convection are shown both analytically and graphically
Molybdopterin biosynthesis - Mechanistic studies on a novel MoaA catalyzed insertion of a purine carbon into the ribose of GTP
No full textAbstract The first step in the biosynthesis of the molybdopterin cofactor involves an unprecedented insertion of the purine C8 carbon between the C2′ and C3′ carbons of the ribose moiety of GTP. Here we review mechanistic studies on this remarkable transformation. This article is part of a Special Issue entitled: Cofactor-dependent proteins: evolution, chemical diversity and bio-applications
Approximate Solutions for the Flow and Heat Transfer due to a Stretching Sheet Embedded in a Porous Medium with Variable Thickness, Variable Thermal Conductivity and Thermal Radiation using Laguerre Collocation Method
Get PDFIn this article, a numerical approach is given for studying the flow of a Newtonian fluid over an impermeable stretching sheet embedded in a porous medium with a power law surface velocity and variable thickness in the presence of thermal radiation. The flow is caused by a non-linear stretching of a sheet. Thermal conductivity of the fluid is assumed to vary linearly with temperature. The governing PDEs are transformed into a system of coupled non-linear ODEs which are using appropriate boundary conditions for various physical parameters. The proposed method is based on replacement of the unknown function by truncated series of well known Laguerre expansion of functions. An approximate formula of the integer derivative is introduced. The introduced method converts the proposed equations by means of collocation points to a system of algebraic equations with Laguerre coefficients. Thus, by solving this system of equations, the Laguerre coefficients are obtained. The effects of the porous parameter, the wall thickness parameter, the radiation parameter, thermal conductivity parameter, and the Prandtl number on the flow and temperature profiles are presented. Moreover, the local skin-friction and Nusselt numbers are presented. Comparison of obtained numerical results is made with previously published results in some special cases. The results attained in this paper confirm the idea that the proposed method is powerful mathematical tool and it can be applied to a large class of nonlinear problems arising in different fields of science and engineering
Kaluza-Klein Type Cosmological Model of the Universe with Inhomogeneous Equation of State
Get PDFIn this paper we study Kaluza-Klein type cosmological model of the universe filled with an ideal fluid obeying an inhomogeneous equation of state depending on time. It is shown that there appears a quasi-periodic universe, which repeats the cycles of phantom type space acceleration