International Journal of Mathematical Research

Published by: Conscientia Beam
Online ISSN: 2306-2223
Print ISSN: 2311-7427
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No. 2

Seasonal Time Series Analysis on Export Performance of Hawassa Green Wood Flower Production (SARIMA Model)

Pages: 60-68
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Seasonal Time Series Analysis on Export Performance of Hawassa Green Wood Flower Production (SARIMA Model)

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DOI: 10.18488/journal.24.2017.62.60.68

Mulugeta Aklilu Zewdie , Yohannes Yibabe

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Mulugeta Aklilu Zewdie , Yohannes Yibabe (2017). Seasonal Time Series Analysis on Export Performance of Hawassa Green Wood Flower Production (SARIMA Model). International Journal of Mathematical Research, 6(2): 60-68. DOI: 10.18488/journal.24.2017.62.60.68
This study focuses in determining the trend and seasonality export performance of stem rose flower at Hawassa Green Wood based on five year monthly data. The data was obtained from secondary and primary source and includes from January 2006/7 to December 2010/11. Both descriptive and inferential Statistical methods of analysis are used to analyses the data. The analysis is done by using Minitab statistical soft ware. The methods of interests are trend analysis and Box-Jenkins SARIMA models. The trend for this data shows an increasing trend however seasonal fluctuation occurs. SARIMA (0, 1, 2) (0, 1, 1) are the selected Box-Jenkins potential model for this data and by using this model forecasted two years ahead.

Contribution/ Originality
This study shows the application of Stochastic Mathematical Model to Real Problems

Lobatto-Runge-Kutta Collocation and Adomian Decomposition Methods on Stiff Differential Equations

Pages: 53-59
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Lobatto-Runge-Kutta Collocation and Adomian Decomposition Methods on Stiff Differential Equations

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DOI: 10.18488/journal.24.2017.62.53.59

Citation: 2

E. U. Agom , F. O. Ogunfiditimi , Edet Valentine Bassey

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E. U. Agom , F. O. Ogunfiditimi , Edet Valentine Bassey (2017). Lobatto-Runge-Kutta Collocation and Adomian Decomposition Methods on Stiff Differential Equations. International Journal of Mathematical Research, 6(2): 53-59. DOI: 10.18488/journal.24.2017.62.53.59
In this paper, we show the parallel of Adomian Decomposition Method (ADM) and Lobatto-Runge-Kutta Collocation Method (LRKCM) on first order initial value stiff differential equations. The former method provided closed form solutions while the latter gave approximate solutions. We illustrated these findings in two numerical examples. ADM solutions were in series form while those of LRKCM gave sizeable absolute error. We further visualized our findings in respective plots to show the great potentials of ADM over LRKCM in providing analytical solutions to stiff differential equations.

Contribution/ Originality
This study contributes in showing the originality of ADM in obtaining exact solution to Stiff differential equations, while LRKCM provided approximate solution whose accuracy depended on step size.

Period Monotonicity for Weight-Homogeneous Differential Systems

Pages: 46-52
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Period Monotonicity for Weight-Homogeneous Differential Systems

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DOI: 10.18488/journal.24.2017.62.46.52

Khalil I.T. Al-Dosary , Hishyar Kh. Abdullah

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Khalil I.T. Al-Dosary , Hishyar Kh. Abdullah (2017). Period Monotonicity for Weight-Homogeneous Differential Systems. International Journal of Mathematical Research, 6(2): 46-52. DOI: 10.18488/journal.24.2017.62.46.52
In this article, integrability, center, and monotonicity of associated period function for  -quasi-homogeneous vector fields are investigated. We are concerned with family of vector field given by sum, finite or infinite number of quasi-homogeneous polynomials not necessarily to be sharing the same weights. The investigation is done by utilizing method of computing focal values. As an application of the result, a particular family of (p, q)-quasi-homogeneous vector field is studied to find conditions for center, monotonicity and consequently an explicit form for the associated period function.

Contribution/ Originality