iosr-Jm   Volume-1 ~ Issue-3

Abstract: In this paper we discus about 'Effect of environmental pollution on the growth and existence biological populations' in terms of H-function

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Abstract: In this paper a steady three dimensional flow of a viscous – incompressible fluid through highly porous medium bounded by a vertical infinite porous plate under the influence of a transverse applied magnetic field, with periodic suction velocity is considered. Governing equations are solved by using perturbation technique and obtained the expressions for velocity and temperature. The above flow quantities are discussed through the graphs for different physical parameters. Also the expressions for shear stress and the rate of heat transfer co-efficient are derived and discussed.
Keywords: MHD, Laminar flow, porous medium, suction velocity, shear stress & Rate of heat transfer.

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[3]. Ling S.C, Nazar .R, Pop.I, (2007), "Steady mixed convection boundary-layer flow over a vertical flat surface in a porous medium filled with water at 40c variable surface Heat flux", Transport in porous Media,vol.70, No.3, pp. 307-321.
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[9]. Singh K.D and Sharma .R, (2000), "Three dimensional couette flow through a porous medium with Heat Transfer", Indian J. pure, appl. math., 32(12), pp. 1819- 1829.
[10]. Raju M. C and Varma S.V.K , Reddy P.V and Suman .S, (2008) "Soret effects due to natural convection between heat inclined plates with Magnetic field", J. of Mechanical Engineering , Vol M.E 39, PP. 43-48.

Abstract: This paper compares the performance of the former model order determination criteria with new Approach in terms of selecting the correct order of an autoregressive time series model in small and large samples. The considered criteria are the Akaike information criterion (AIC); Scwarz information criterion (SIC), the Hannan − Quinn criterion (HQ) and the three new median criteria. Our results show that the median between AIC and Scwarz (MAS) criterion performs best in terms of selecting the correct order of an Autoregressive model for small and large samples sizes. Scwarz, Hannan Quinn, the median of Akaike and Hannan Quinn (MAH) criteria and median of Scwarz and Hannan Quinn can be said to perform best in large samples. The comparison of the six model selection criteria was in terms of their percentage of number of times that they identify the "true" model. The simulation results indicate that overall, the proposed Median of Akaike and Scwarz (MAS) information criterion showed very good performance in this simulation study. So, we recommend median of Akaike & Schwarz (MAS), Median of Schwarz & Hannan Quinn (MSH), and median of Akaike &Hannan Quinn information criterion as reliable criteria to identify the "true" model.
Keywords: Information criteria, best performance, new median information criteria.

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