Open Access Short communication

The Acorn Adjustments of Australian Temperatures are in the Wrong Direction

A. Parker

Physical Science International Journal, Page 245-252
DOI: 10.9734/PSIJ/2015/17270

We previously discussed as the warming of Australia evidenced by the Australian Climate Observations Reference Network (ACORN) data set is artificially created by the arbitrary correction of the truly measured temperatures making cooler the temperatures of the past [1-4]. Gillham [5] has freshly brought to the attention of the scientific community two old data sets that further support our claim, proving once more how the ACORN corrections are wrongly set up to magnify the warming trend where actually they should rather cancel the urban heat island effect reducing the trend.

 

Open Access Original Research Article

Estimation of Wind Power Potential of Six Sites in Eastern Cape Province of South Africa

Chipo Shonhiwa, Golden Makaka, Kudakwashe Munjeri

Physical Science International Journal, Page 209-218
DOI: 10.9734/PSIJ/2015/16699

Aims: To use the five year wind speed measurements to assess the wind power potential of six sites of part of the Eastern Cape Province.

Study Design: The potential for generating electricity from wind was assessed for six sites of the western part of the Eastern Cape Province (Bisho, Fort Beaufort, Graaff – Reinet, Grahamstown, Port Elizabeth and Queenstown)

Place and Duration of Study: The study was carried out at University of Fort Hare, South Africa between June and December 2014.

Methodology: The five-year-long, hourly average wind speed series between January 2009 and December 2013 for the six Eastern Cape weather stations were obtained from South African Weather Services (SAWS). The data was statistically analysed using the Weibull distribution function in MATLAB.

Results: The dimensionless Weibull shape parameter, k, varied from 1.7 to 2.2, while the scale parameter, c, varied between 3.5 and 6.3 connected power generation while an average of 3 ms-1 to 4 ms-1. The most probable wind speed, vmp, expected in the province ranged from 2.1 to 4.1 connected power generation while an average of 3 ms-1 to 4 ms-1. The wind power densities ranged from 34.7 to 207.8 Wm-2. The annual Weibull probability density frequency curves vary from site to site, in both its shape and maximum value and are all skewed towards lower wind velocities except for Port Elizabeth

Conclusion: Basing on the American Wind Energy Association (AWEA) classification, Fort Beaufort, Graaff– Reinet and Queenstown correspond to wind power class 1 while Bisho and Grahamstown correspond to class 2. Consequently they are not suitable for installation of large turbines for grid connection. Nevertheless, they are suitable for stand-alone systems. Port Elizabeth corresponds to class 4 and hence is suitable for grid connected applications. It is thus recommended to install large turbines for grid connected applications in Port Elizabeth and small scale wind turbines for stand-alone applications such as supplying power to individual houses and irrigation in Bisho, Fort Beaufort, Graaff – Reinet, Grahamstown and Queenstown.

 

Open Access Original Research Article

Investigation of Disordered State in the Distribution of Diluted Interaction Coupling Using Ising Spin Model in Two Dimension

Habte Dulla Berry

Physical Science International Journal, Page 219-224
DOI: 10.9734/PSIJ/2015/16087

In this study long range interaction coupling Ising spin-glass systems with () are considered. Monte Carlo approach of the critical behavior is presented and also in presence of diverging thermodynamical fluctuations at the critical point the behavior of the model is shown to be of the Replica Symmetry Breaking type. The parallel tempering algorithm has been used to simulate the dynamical approach to equilibrium of such systems. The author has obtained phase transition temperatures for different linear lattice sizes (L=10, 20, 30, 40 &  ) but for    and larger sizes there is no phase transition.

 

Open Access Original Research Article

Geochemical and Geotechnical Characteristics of Soil within Oke-diya Dumpsite in Sagamu South Western Nigeria

A. M. Odukoya, A. Sama

Physical Science International Journal, Page 225-235
DOI: 10.9734/PSIJ/2015/14261

This research was to determine geotechnical and geochemical characteristics of soil around Oke diya dumpsite in Sagamu Southwestern Nigeria. Five soil samples were collected within dumpsite at depth of 0-20 cm to determine their engineering properties in accordance with the British Standards. Another eight (8) soil samples were collected vertically at the depth of 1m interval for geochemical analysis using Inductively Coupled Plasma-Mass Spectrophotometer method (ICP MS).

The specific gravity value ranges between 2.78–3.00 which fall within moderate degree of laterization and dehydration. The soil generally can be classified as silty sand of intermediate to high plasticity or compressibility based on the percentage grain size distribution and Casagrande Plasticity Chart. Permeability tests showed low permeability within the range of 1.8 x 10-6 cm/s – 2.12 x 10-6 cm/s. Therefore the soil has capacity to provide long term protection of groundwater by natural attenuation as a result of the thickness of the unsaturated zone, high silt content and low permeability.

Thirty one elements were determined in the soil samples. The relative abundance of the major and significant trace elements followed the order Al > Fe > K > Mg > Ca > Ti > Na > S > P and V > Mn > Cr > Ba > Sr > Cu > Zn > Pb > Zr > Ni > Sc > Y > Co > Mo respectively. There was a general trend of decrease in metals concentration as the depth of sampling increases.

Result of geo-accumulation index showed that the soil samples were practically uncontaminated with Mn, Ni, Zn, Ba, Cr, Sc, Co, Sr, Cu, Zr and Y, practically to moderately contaminated with Pb and V and was moderately contaminated with Mo. Other contamination assessment showed that the soil fall within low contamination factor with all the trace elements except with Pb which falls within moderately contamination.

 

Open Access Original Research Article

Nonplanar Solitary Waves and Shock Waves in a Nonextensive Plasma

S. Ashraf, G. Mandal, A. A. Mamun

Physical Science International Journal, Page 236-244
DOI: 10.9734/PSIJ/2015/13086

Aims/ Objectives: We have studied the nonlinear wave propagation in an unmagnetized plasma system containing initialy cold viscous ion fluids and nonextensive electron fluids with nonplanar geometry.
Place and Duration of Study: Department of Electronics and Communications Engineering, East West University and Department of Physics, Jahangirnagar University.
Methodology: We have used reductive perturbation method to derive K-dV and Burgers’ equations and numerically obtained their solutions to study the basic characteristics of ion-acoustic (IA) solitary waves (SWs) and shock waves (ShWs) in nonplanar geometry.
Results: It has been shown that the combined effects of nonextensive electron distribution and coefficient of ion viscosity significantly modify the behavior of Sws and ShWs. It has been also found to exist for positive and negative potential with cylindrical and spherical geometry in our this assumed plasma model.
Conclusion: The present analysis may be useful to understand and demonstrate the dynamical properties of nonlinear waves in different astrophysical and cosmological objects.

Open Access Review Article

A Method for Computing Initial Approximations for a 3-parameter Exponential Function

C. R. Kikawa, M. Y. Shatalov, P. H. Kloppers

Physical Science International Journal, Page 203-208
DOI: 10.9734/PSIJ/2015/16503

This paper proposes a modified method (MM) for computing initial guess values (IGVs) of a single exponential class of transcendental least square problems. The proposed method is an improvement of the already published multiple goal function (MGF) method. Current approaches like the Gauss-Newton, Maximum likelihood, Levenberg-Marquardt etc. methods for computing parameters of  transcendental least squares models use iteration routines that require IGVs to start the iteration process. According to reviewed literature, there is no known documented methodological procedure for computing the IGVs. It is more of an art than a science to provide a “good” guess that will guarantee convergence and reduce computation time.

To evaluate the accuracy of the MM method against the existing Levenberg-Marquardt (LM) and the MGF methods, numerical studies are examined on the basis of two problems that’s; the growth and decay processes. The mean absolute percentage error (MAPE) is used as the measure of accuracy among the methods. Results show that the modified method achieves higher accuracy than the LM and MGF methods and is computationally attractive. However, the LM method will always converge to the required solution given “good” initial values.

The MM method can be used to compute estimates for IGVs, for a wider range of existing methods of solution that use iterative techniques to converge to the required solutions.