July 2008

A robust observer design for chaos synchronization of uncertain systems using LMI criterion

In this paper, considering the effect of exoteric perturbation on system’s parameters, a robust observer, based on Lyapunov theory, is designed for the output synchronization of a class of uncertain systems when the full state vector is not available. With the help of LMI criterion and then using the MATLAB LMI Toolbox, the observer gain L is derived, which can not only make the...

Author(s): Xiaojue Ma

July 2008

Complexation of cobalt (II) with nicotinohydroxamic acid and its microbial sensitivity

Complex of cobalt (II) with nicotinohydroxamic acid (NHA) has been investigated by spectroscopic method at 25 ± 0.1oC in aqueous solution of 0.1mol dm-3 ionic strength. The results reveal the sole formation of 1:2 complex at equilibrium. Spectra and magnetic studies of the isolated complex indicate octahedral mixed coordination mode (N.O). Microbial sensitivity test on eight micro-organism (that is, four...

Author(s): Aliyu A. O. and Nwabueze J. N.

July 2008

Lamda-mu-rho technique as a viable tool for litho-fluid discrimination - The Niger-Delta example

The focus of this paper is to discriminate fluid and lithology in the tertiary Niger Delta using the Lamda-mu-rho technique. This involves the use of basic rock Physics, Amplitude Variation with Offset (AVO), and seismic amplitude inversion to show the effectiveness of this technique in an oil sand reservoir. The data used in this study include pre-stack seismic data and well log data. The result shows the effectiveness...

Author(s): Ujuanbi O, Okolie J. C and Jegede S.I