Department Of Physics

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https://ir.unilag.edu.ng/handle/123456789/3391
The Department provides tutorial and/or research courses at undergraduate and postgraduate levels leading to the award of the degrees of Bachelor of Sciences (Honours) (B.Sc.), the Master of Science (M.Sc.), Master of Philosophy (M.Phil.) and Doctor of Philosophy (Ph.D.) in Physics respectively. Physics is one of the basic experimental physical sciences.

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Browsing Department Of Physics by Author "Adewale, Adekola"

Now showing 1 - 3 of 3
  • Item
    Open Access
    Comparison between observed ionospheric foF2 and IRI-2001 predictions over periods of severe geomagnetic activities at Grahamstown, South Africa
    (Elsevier Ltd, 2010) Adewale, Adekola; Oyeyemi, Elijah; Ofuase, U.
    The observed ionospheric F2 critical frequency (foF2) values over a South Africa mid-latitude station, Grahamstown, (geographic coordinates: 33.3 S, 26.5 E), were analysed and compared with International Reference Ionosphere (IRI) model, using the CCIR (Comite ´ Consultatif International des Radio communications) and URSI (Union Radio-Scientifique Internationale) coefficients, during four geomagnetically disturbed days in the year 2000. These days are April 5, May 23, August 10 and September 15. The data were analysed for five days around the storm day. Comparisons between the IRI-2001 predicted foF2 values, using both CCIR and URSI coefficients and the observed values are shown with their root-mean-square error (RMSE) and the relative deviation module mean (rdmm) for the various storm periods. The CCIR option performed more accurately than the URSI option. In general, the model generates good results when compared with observed foF2 values during geomagnetic storms, although some improvements are still necessary to be implemented in order to obtain better predictions.
  • Item
    Open Access
    Comparison between observed ionospheric foF2 and IRI-2001 predictions over periods of severe geomagnetic activities at Grahamstown, South Africa
    (Advances in Space Research, 2010) Adewale, Adekola; Oyeyemi, Elijah; Ofuase, Uche
    The observed ionospheric F2 critical frequency (foF2) values over a South Africa mid-latitude station, Grahamstown, (geographic coordinates: 33.3 S, 26.5 E), were analysed and compared with International Reference Ionosphere (IRI) model, using the CCIR (Comite´Consultatif International des Radio communications) and URSI (Union Radio-Scientifique Internationale) coefficients, during four geomagnetically disturbed days in the year 2000. These days are April 5, May 23, August 10 and September 15. The data were analysed for five days around the storm day. Comparisons between the IRI-2001 predicted foF2 values, using both CCIR and URSI coefficients and the observed values are shown with their root-mean-square error (RMSE) and the relative deviation module mean (rdmm) for the various storm periods. The CCIR option performed more accurately than the URSI option. In general, the model generates good results when compared with observed foF2 values during geomagnetic storms, although some improvements are still necessary to be implemented in order to obtain better predictions.
  • Item
    Open Access
    Comparisons of observed ionospheric F2 peak parameters with IRI-2001 predictions over South Africa
    (Elsevier Ltd, 2009) Adewale, Adekola; Oyeyemi, Elijah; McKinnell, Lee-Anne
    The monthly means of the ionospheric F2 peak parameters (foF2 and hmF2) over three stations in South Africa (Grahamstown,33.31S, 26.51E, Madimbo, 22.41S, 26.51E, and Louisvale, 28.51S, 21.21E) were analyzed and compared with IRI-2001, using CCIR (Comite´ Consultatif International des Radio communications)and URSI (Union Radio-Scientifique Internationale coefficients)options. The analysis covers a few selected quiet and disturbed days during various seasons represented by the months of January, April, July and October 2003. IRI-2001 generally over estimates hmF2 for both quiet and disturbed days and it over estimates and underestimates foF2 at different times for all the stations. In general, foF2 is predicted more accurately by IRI-2001 than hmF2, and on average, the CCIR option performed better than the URSI option when predicting both foF2 and hmF2. In general, the model generates good results, although some improvements are still necessary to be implemented in order to obtain better predictions. There are no significant differences in the model predictions of hmF2 and foF2 for quiet and disturbed days.