Siti Khuzaimah Soid

Thermal boundary layer flow on a stretching plate with radiation effect

A steady two-dimensional laminar forced convection boundary layer flow over a stretching plate immersed in an incompressible viscous fluid is considered. The stretching velocity is assumed to vary linearly with the distance from the leading edge. The governing partial differential equations are first reduced to ordinary differential equations using a similarity transformation, before being solved numerically using MAPLE software, which based on the Runge-Kutta-Fehlberg method. Besides, the solution for the thermal field is also given in terms of Kummers function. The effects of the radiation parameter and the Prandtl number on the heat transfer characteristics are obtained and discussed. It is found that the heat transfer rate at the surface increases as the Prandtl number increases but decreases with the radiation parameter.

Magnetohydrodynamics (MHD) boundary layer flow over a stretching cylinder embedded in a porous medium

A steady axisymmetric boundary layer flow of an incompressible viscous fluid along a stretching cylinder embedded in porous medium in the presence of magnetic field is studied. The governing partial differential boundary layer equations with boundary conditions are first transformed into ordinary differential equations using similarity transformation before being solved numerically by a finite-difference method. The effects of magnetic parameter, curvature parameter, permeability parameter and Prandtl number on the characteristics of heat transfer were analyzed. It is found that the local Nusselt number decreases with increasing magnetic parameter. The velocity decreases with the increase of magnetic and permeability parameters. Both parameters present resistance to the flow, thus the flow becomes slower.

MHD stagnation point flow over a stretching/shrinking sheet

The problem of unsteady magnetohydrodynamic (MHD) stagnation point flow over a stretching/shrinking sheet is studied in this paper. By using proper variables, the partial differential equations are transformed into an ordinary (similarity) differential equation. This equation along with the corresponding boundary conditions are solved numerically using boundary value problems solver (bvp4c) in Matlab software. It is found that dual (first and second) solutions exist for the similarity equation. The results are shown in a table and four figures for several values of the governing parameters.

Project evaluation and selection using fuzzy Delphi method and zero - one goal programming

Project evaluation and selection is a factor affecting the impotence of board director in which is trying to maximize all the possible goals. Assessment of the problem occurred in organization plan is the first phase for decision making process. The company needs a group of expert to evaluate the problems. The Fuzzy Delphi Method (FDM) is a systematic procedure to evoke the groups opinion in order to get the best result to evaluate the project performance. This paper proposes an evaluation and selection of the best alternative project based on combination of FDM and Zero - One Goal Programming (ZOGP) formulation. ZOGP is used to solve the multi-criteria decision making for final decision part by using optimization software LINDO 6.1. An empirical example on an ongoing decision making project in Johor, Malaysia is implemented for case study.

Resource allocation in road infrastructure using ANP priorities with ZOGP formulation-A case study

Road Infrastructure (RI) project evaluation and selection is concern with the allocation of scarce organizational resources. In this paper, it is suggest an improved RI project selection methodology which reflects interdependencies among evaluation criteria and candidate projects. Fuzzy Delphi Method (FDM) is use to evoking expert group opinion and also to determine a degree of interdependences relationship between the alternative projects. In order to provide a systematic approach to set priorities among multi-criteria and trade-off among objectives, Analytic Network Process (ANP) is suggested to be applied prior to Zero-One Goal Programming (ZOGP) formulation. Specifically, this paper demonstrated how to combined FDM and ANP with ZOGP through a real-world RI empirical example on an ongoing decision-making project in Johor, Malaysia.

Radiation effects on laminar boundary layer flow along a stretching cylinder

A steady boundary layer flow and heat transfer over a continuously stretching cylinder in the presence of radiation is examined. By similarity transformation, the governing partial differential equations are transformed to nonlinear ordinary differential equations. Numerical solutions are obtained by employing the implicit finite difference of Keller-box scheme. The effects of radiation parameter, curvature parameter and Prandtl number on the heat transfer on the surface were discussed. It can be concluded that as the radiation parameter increases, the heat transfer decreases, while when Prandtl number or temperature exponent increases, the heat transfer at the surface increases.

Optimizing secondary school budget — A case study

Many activities are planned by an organization; however there are some constraints that must be considered. Therefore, the selection of the best activities is important to maximize the achievement of the organizations goals. Zero-One Goal Programming (ZOGP) model is used to select the best activities to be done throughout the year by considering the selected constraints. This method takes into account the weightage given by selected teachers. This investigation involved a secondary schools co-curriculum activities at Sekolah Agama Menengah Jeram (SAMJ), Selangor subject to their budgeting problems. The powerful computer software, LINDO 6.1 is used to obtain the optimal solution to generate solutions for decision variables where the variables must be equal to one or zero. From the results obtained, we can conclude that only two activities are not selected. Therefore, this ZOGP is an optimal method to be applied in solving the SAMJs co-curriculum activities selection problem.