International Journal of
Physical Sciences

  • Abbreviation: Int. J. Phys. Sci.
  • Language: English
  • ISSN: 1992-1950
  • DOI: 10.5897/IJPS
  • Start Year: 2006
  • Published Articles: 2556

Table of Content: 22 June, 2012; 7(24)

June 2012

A neural network approach for cumulative monthly rainfall time series forecasting tuned by roughness

In this work a feed-forward neural networks (NN) based nonlinear autoregressive filter (NAR) approach for forecasting cumulative monthly rainfall time series is presented. The filter parameter adjustment is performed in accordance with time series roughness. This method has concordance with the long or short term stochastic dependence of the time series and the proposal is an on-line heuristic law to set the training...

Author(s): Julián A. Pucheta, Cristian M. Rodríguez Rivero, Martín R. Herrera, Carlos A. Salas, H. Daniel Patiño and Benjamín R. Kuchen        

June 2012

Query expansion based on contextual meaning of the query terms

In this paper, a new method for query expansion is proposed which expands the original query based on the contextual meaning of it. User provides the method with an original query and a set of relevant documents. The term space extracted from the relevant documents by the vector space model is transformed to a topic space by means of latent semantic analysis. The terms’ projections in the topic space are grouped...

Author(s): Marziea Rahimi, and Morteza Zahedi      

June 2012

Synthesis, characterization, theoretical calculations and biological studies of potassium trifluorothiocyanoborate (III)

Synthesis, characterization, spectral and theoretical calculations of potassium trifluorothiocya noborate (III) (PTFTCB) has been studied. Potassium trifluorothiocyanoborate (III) was synthesized and characterized by IR, UV/VIS, 11B-NMR and mass spectrometer techniques. The structure of synthesized compound was optimized at the B3LYP/LANL2DZ level of theory and theoretical parameters such as structural data, molecular...

Author(s): Shahriar Ghammamy and Sajjad Sedaghat      

June 2012

Studies on mass attenuation coefficients, effective atomic and electron numbers for Cd1-xZnxTe alloy at photon energies of 10 to 100 keV

The physical parameters calculated using Full Potential Linear Muffin Tin Orbitales FP-LMTO method is satisfying. Using the photon mass attenuation coefficient obtained via XCOM data of Cd1-xZnxTe compound, the effective atomic number and the effective electron number were determined in the energy range of 10 to 100 keV. The effective atomic and electron numbers are linearly related and they also depend on the incoming...

Author(s): A. Saim, A. Tebboune, M. N. Belkaid, H. Berkok and A. H. Belbachir      

June 2012

East African rainfall seasonality based on modulated annual cycle (MAC)

The spatial and temporal variability of East African rainfall seasonal cycle is investigated based on modulated annual cycle (MAC). Ensemble empirical mode decomposition (EEMD) is used to extract MAC from monthly data for the period 1900 to 2008.  The MAC is given by year-to-year changes in annual and semi-annual components. Results show that MAC account for between 45 to 80% proportion of rainfall variability....

Author(s): Zablone Owiti, and Weijun Zhu      

June 2012

Synergetic performance of palm oil (Elaeis guineensis) and pine oil (Pinus sylvestris) as binders on foundry core strength

Possibilities of foundry sand core binders made with combination of Elaeis guineensis andPinus sylvestris have been evaluated and the combine effect of these oils as binder were discussed. Core specimens made with Ota silica base sand bonded with 6% of cassava starch in admixed proportion of E. guineensis and P. sylvestris were tested for tensile, compressive strength...

Author(s): Popoola, A. P. I., Abdulwahab, M. and Fayomi, O. S. I.        

June 2012

Laminar boundary layer flow along a stretching cylinder embedded in a porous medium

Laminar boundary layer flow of an incompressible viscous fluid along a stretching horizontal cylinder embedded in a porous medium is discussed. The governing system of partial differential equations is reduced to a system of ordinary differential equations. Mathematics has been used to solve such system after obtaining the missed initial conditions. The obtained results are compared with previously published results in...

Author(s): E. M. A. Elbashbeshy, T. G. Emam, M. S. El-Azab and K. M. Abdelgaber      

June 2012

Impact of frequency switching on the efficiency of a fully suspended active magnetic bearing system

Due to the rising energy (and electricity) cost it is essential that an active magnetic bearing (AMB) system is operated as efficiently as possible. Frequency switching caused by an external source can cause an AMB system to operate at a higher than expected energy level and lower than expected efficiency. The purpose of this paper is therefore to investigate the impact of frequency switching (caused by an external...

Author(s): Rupert Gouws    

June 2012

Probing relation between solar activities and seismicity

In this paper, we studied the relationship between sunspots numbers (SNs), solar 10.7 cm radio flux (SRF), solar irradiance (SI), solar proton events (SPEs) and local earthquakes. The location of the study is selected in Iran area and all earthquakes data chosen for M≥ 4 from 1970 to 2010. The study reveals the following conclusions: (i) The total number of local earthquakes in maximum years of solar activities is...

Author(s): Bijan Nikouravan,, J. J. Rawal, Rahman Sharifi and Mahmoud Nikkhah