ABSTRACTS OF VOLUME 3 :
Journal of the Nigerian Association of Mathematical Physics(1999)
ISBN: 1116-4336

TOPICS & CONTRIBUTORS :
(please click on the hyperlinked title of each article to go to the abstract)

1) De-Sitter group approach to the Theory of Gravitation
by; Awele Maduemezia, Department of Physics, University of Ibadan ,Ibadan, Nigeria

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2) Error Estimation in the Gauss and Newton-Cotes Quadrature Schemes for Weak Solutions of Quantum Stochastic Differential Equation
by ; E. O Ayoola , Department Of Mathematics, University Of Ibadan, Ibadan, Nigeria.

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3) On Estimation of Entropy Value for an Organization
by; S. E. Omosigho, Department of Mathematics, University of Benin, Benin City, Nigeria.
and A. O. Osagiede, Institute of Education, University of Benin, Benin City, Nigeria

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4) Delay Differential Equations and Finite-Dimensional Iterated Mapping
by ; Ibiyinka A. Fuwape, Department of Physic, Federal University of Technology, Akure, Nigeria.

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5) Synchronization of Chaotic Systems
by; Ibiyinka A. Fuwape, Department of Physics, Federal University of Technology,
Akure, Nigeria

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6) An Optimization Technique for the Retarded Differential Delay Equation
by; F. M. Okoro, Department of Computeer Science and Statistics, Edo State University, Ekpoma, Nigeria
and M A. Ibiejugba, Department of Mathematics University of Ilorin, Ilorin Nigeria

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7) An Extended Conjugate Gradient Algorithm For Discrete Optimal Control Problems.
by ; Francis O. Otunta, Department of Mathematics, University of Benin, Benin City, Nigeria

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8) Mutipoint Iteration Methods For Sparse System of Linear Equations
by; M.N.O Ikhile, Department of Mathematics,University of Benin, Benin City, Nigeria

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9) On Derivation of New Numerical Integrator for Solving Linear Stiff First Order Initial Value Problem with Constant Matrix of Order 2
by ; Julian Ibezimako Mbegbu, Department of Mathematics and Computer Science University of Benin, Benin City, Nigeria

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10) Spin Density In Cu2O Plane of YBa2Cu307 Probed by CuNMR Measurements
by E.O. Aiyohuyin , Department of Physics, University of Benin, Benin City, Nigeria

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11) Unified Hamiltonian Model for Magnetism and Superconductivity in High-Tc Cuprate Systems
by ; G. C. Asomba, Department of Physics And Astronomy,University of Nigeria of Nigeria, Nsukka, Nigeria
and A. O. E Animalu, National Mathematical Center, Abuja, Nigeria

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12) Possible Electronic Energy Structure of High-Tc Cuprates
by; G. C. Asomba, Department of Physics and Astronomy, University 0f Nigeria, Nsukka, Nigeria

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13) Estimating the Stability of Some Alkalimetal Clusters Li, Li And Nana* using Local Spin Density Functional Formalism
by; J. S. Ononiwu, Department of Physics, Federal University of Technology, Owerrri, Imo State, Nigeria

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14) Implementation of Equivalent Crystal Theory within a generalized embedded-Atom Method
by ; J. O. A. Idiodi, Department of Physics,University of Benin, Benin City, Nigeria
and E. Aghemenloh, Department of Physics, Ambrose Alli University, Ekpoma, Nigeria

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15) Discrete Eigenvalues of a Modified Pöschl-Teller Potential Hole using Semi-Classical Approximation
by; K. J. Oyewumi, Department of Pure and Applied Mathematics, Ladoke Akintola Univeristy of Technology, P. M. B. Ogbomoso, Oyo State, Nigeria.
and E. A. Bangudu, Department of Mathematics, University of Ilorin, P. M. B. 1515, Ilorin, Kwara State, Nigeria.

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16) Computation of the Kernel Function by inversion of resistivity field data from Schlumberger Configuration
by; M. B. Asokhia, S.O. Azi, F. O. Onwuka and O. Ujuanbi, Department of Physics, Edo State University, Ekpoma

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17) Noise reduction and cancelling stationary sinusoidal noise in Seismic data acquisition in Atala prospect of River State
by ; J. C. Egbai, Edo State University, Ekopma, Nigeria

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18) Generalized Solutions to nonlinear parabolic equations.
by; E. O. Ifidon and E. O. Oghre, Department of Mathematics, University of Benin, Benin City, Nigeria.

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19) On the numerical simulation to Blasius’ Equation for Dimensionless Shear Stress
by; A. S. Adekola, Department of Physics, Federal University of Technology, Akure, Ondo State, Nigeria.

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20) The Dynamic Analysis of an Elastic plate with point-moving load
by; Y. M. Aiyesimi, Department of Mathematics and Computer Science, Federal University of Technology, Minna, Nigeria.

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21) Numerical solution for a non-Boussinesque radiative flow in the Annulus of concentric rotating spheres
by; Y. M. Aiyesimi, Department of Mathematics and Computer Science, Federal University of Technology, Minna, Nigeria.

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22) A steady flow of fluid in an open rectangular container
by ; P. B. Shola, Department of Mathematics, University of Ilorin, Ilorin, Nigeria.

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23) Phase plane analysis of liquid front moving through a hot porous rock
by; R. O. Ayeni, Department of Pure and Applied Mathematics, Ladoke Akintola Univeristy of Technology, Ogbomoso, Nigeria.

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24) On the Evolutions of the Ocean wave generated low frequency Seismic noise
by; E. O. Okeke, C. Adejayan, Department of Mathematics, Univeristy of Benin, Benin City, Nigeria
and V. E. Asor, The Shell Petrolleum Development Company of Nigeria Limited, Warri

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25) Criteria for unique solution of a radial porous medium combustion
by; O.K. Koriko, Department of Industrial Mathematics and Computer Science, Federal University of Technology, Akure.

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26) On a family of methods for simultaneous inclusions of zeros of polynomial and analytic functions inside a simple smooth closed contour in the complex plane.
by; S. E. Uwamusi, Department of Mathematics, Faculty of Science,University of Benin, Benin City, Nigeria.

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27) The saturation of bean-excited ionospheric lover hybrid resonance through ion acceleration
by Salihu S. Duwa, Department of Physics, Bayero University, Kano, Nigeria
and B. Chike-Obi, Department of Physics, University of Ilorin, Nigeria.

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28) Theoretical significance of field measurements of radioactive leaf and canopy temperatures
by; A. A. Olufayo, Department of Agricultural Engineering, Federal University of Technology, Akure, Ondo State.

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29) Remotely sensed crop canopy temperature, ambient relative humidity and air Temperature: Theoretical Analysis and Experimental verification
by; A. A. Olufayo, Department of Agricultlural Engineering, Federal University of Technology, Akure, Ondo State.

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30) Sensitivity and error analysis of Blaney-Morin-Nigeria evapotranspiration model
by; P. G. Oguntunde, Deparment of Agricultural Engineering, Federal University of Technology, Akure, Nigeria.
F. I. Alao, Department of Mathemtics and Compuer Science, Federal University of Technology, Akure, Nigeria.
and A. A. Olufayo, Department of Agricultural Engineering, Federal University of Technology, Akure, Nigeria.

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31) Analytical solutions of the Bloch equations for MRI flow dependent magnetization and signals with spatially varying Magnetic field
by ; O. B. Awojoyogbe, Department of Physics, Federal University of Technology Minna, Niger State, Nigeria.

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32) An expression for Ez component of spatial non-uniform Electromagnetic source fields in low latitude.
by; D. D. Abajingin and G. N. Obodi, Ondo State University, Ado Ekiti, Nigeria.

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33) Potential distribution and focusing properties of an equidiameter co-axial cylindrical electrostatic lens
by A. M. Awobode, Department of Physics, University of Ibadan, Nigeria
and O. M. Oni, Departments of Pure and Applied Physics, Ladoke Akintola University of Technology, P. M. B. 4000, Ogbomoso, Nigeria

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34) Electrostatic energy matrices for sub-configuration of ions in octahedral crystal field
by; I. M. Mejeha, Department of Physics, Federal University of Technology, Owerri, Imo State, Nigeria.

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1)

De-Sitter group approach to the Theory of Gravitation

( page 1 – 11 of Vol 3 Namp Journals )

by Awele Maduemezia
Department of Physics, University of Ibadan, Ibadan, Nigeria


Abstract
By a suitable choice of metric, curved space-time is realized as a 4- dimensional metric space of class 1, i. e., it is imbedded in (flat) (4+1) de-Sitter space. By this stratagem an alternative derivation is achieved of one of the well-known results of the theory of general relativity, namely the precession of the perihelia of the planets Mercury, Venus, the Earth, and Icarus. The results are in good agreement with experiment. The derivation leads to the emergence of a fundamental unit of length, a = c/ (8G) = 0.481856 x 10 m, where =10 Jmis a fundamental stress- energy surface density, and G is the Newtonian universal gravitational constant.

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2)

Error Estimation in the Gauss and Newton-Cotes Quadrature Schemes for Weak Solutions of Quantum Stochastic Differential Equation

( page 12 – 35 of Vol 3 Namp Journals )

by E. O Ayoola
Department Of Mathematics, University Of Ibadan, Ibadan, Nigeria.


Abstract
Gauss and Newton-Cotes Quadrature Schemes For Computing Weak Solutions Of Lipschitzian Quantum Stochastic Differential Equations (QSDE) driven by certain operator valued stochastic processes associated with creation, annihilation and gauge operators of quantum field theory in a local convex space are introduced and their error estimates are studied. The work is accomplished within the frame work of Hudson–Parthasarathy formulation of quantum stochastic calculus, results concerning the consistency and convergence of the schemes in the topology of the locally convex space are presented. This generalized analogous results for classical initial value problem to he equivalent form of noncommutative quantum stochastic differential equations involving unbounded linear operators on a Hilbert space.

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3)

On Estimation of Entropy Value for an Organization

( page 36 – 42 of Vol 3 Namp Journals )

by S. E. Omosigho
Department of Mathematics, University of Benin, Benin City, Nigeria.
and A. Q. Osagiede
Institute of Education, University of Benin, Benin City, Nigeria


Abstract
The paper considers the use of entropy to measure the stability of workforce of an organization by making use of mainly wastage data of Edo State Teaching Service to estimate the wastage probability of each length of service interval. It is found necessary to study the degree of experience present in Edo State Teaching Service due to the present economic situation and the state government embargo on employment in recent years. The study also modifies the log-normal model of Chu and Lin (1994) to calculate the wastage probabilities to tenure classes. Entropy is also calculated based on this modified log -normal wastage rates (probabilities) and a comparison is made between the two entropy values. Bowey’s stability curves are drawn for the actual wastage proportions (probabilities) of PPEB and the modified log-normal wastage proportions to authenticate the entropy results.

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4)

Delay Differential Equations and Finite-Dimensional iterated Mapping

( page 43 – 47 of Vol 3 Namp Journals )

by Ibiyinka A. Fuwape
Department of Physic, Federal University of Technology, Akure, Nigeria.

Abstract
Delay-differential Equation’s (DDE) are currently been used to model high dimensional dynamical systems, which exhibit very complex hyper-chaotic behaviour. An attempt has been made to replace the singularly perturbed differential-delay equation, which is a continuous infinite dimensional dynamical systems with finite dimensional iterated mappings

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5)

Synchronization of Chaotic Systems

( page 48 – 54 of Vol 3 Namp Journals )

by Ibiyinka A. Fuwape
Department of Physics, Federal University of Technology, Akure, Nigeria

Abstract
A new approach for constructing chaotic synchronized systems by linking them with common signals has been made. Attempts were made to synchronize the globally coupled map (GCM), which is a model for non-linear spatially extended systems. The transverse Iyapunov exponent was calculated numerically. A particular case of N =3 has been investigated and some clustering have been observed for this system

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6)

An Optimization Technique for the Retarded Differential Delay Equation

( page 55 – 74 of Vol 3 Namp Journals )

by F. M. Okoro
Department of Computeer Science and Statistics, Edo State University, Ekpoma, Nigeria
and M A. Ibiejugba
Department of Mathematics University of Ilorin, Ilorin Nigeria

Abstract
Models in natural settings sometime include the present and also the past states of the system. This is natural in application in many branches of human endeavour. In this work, the minimization of a quadratic cost functional subject to the retarded differential delay equation is presented. The elegant algorithm of the Extended Conjugate Gradient Method (ECGM) originated in [1].

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7)

An Extended Conjugate Gradient Algorithm For Discrete Optimal Control Problems.

( page 75 – 88 of Vol 3 Namp Journals )

by Francis O. Otunta
Department of Mathematics, University of Benin, Benin City, Nigeria

Abstract
Discrete optimal control problem arise in many multistage and scheduling problems. In principle also, continuous optimal control problems may be discretized appropriately and subsequently be formulated as discrete optimal control problems. Herein, we propose an algorithm, based on the conjugate gradient method for solving discrete optimal control problems with constraints on the states and controls for the dynamical system.

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8)

Mutipoint Iteration Methods For Sparse System of Linear Equations

( page 89 – 105 of Vol 3 Namp Journals )

by M.N.O Ikhile,
Department of Mathematics, University of Benin, Benin City, Nigeria

Abstract
In this report we investigate the effects of incorporating past information in the gauss-Jacobi iteration method for large sparse linear system of equations. It is considered that under certain restrictions convergence is assured, by the implementation requires extra-storage locations. This may not be a serious handicap considering the enormous storage capacity of emerging parallel computers. More consoling is the fact that the resultant algorithm possesses explicit potential for parallelism, although the exploitation of these is not our purpose herein. However, our finding raises the question as to whether there is any need pursuing multipoint iteration methods for spares linear system of equations as a separate method.

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9)

On Derivation of New Numerical Integrator for Solving Linear Stiff First Order Initial Value Problem with Constant Matrix of Order 2

( page 106 – 114 of Vol 3 Namp Journals )

by Julian Ibezimako Mbegbu
Department of Mathematics and Computer Science, University of Benin, Benin City, Nigeria

Abstract
In the light of Fatunla [1], a new numerical integrator for solving stiff first order initial value problem with constant matrix of order 2 was derived based on the interpolating function where A, B, C, are vectors with real entries and is a complex eigen value with the complex conjugate of Application of this linear integrator to stiff first order initial value problem with constant matrix of order 2 gives an encouraging approximation to the exact solution. The integrator is exponentially fitted and L-stable.

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10)

Spin Density In Cu2O Plane of YBa2Cu307 Probed by CuNMR Measurements

( page 115 – 120 of Vol 3 Namp Journals )

by E.O. Aiyohuyin
Department of Physics, University of Benin, Benin City, Nigeria

Abstract
The nuclear magnetic resonance (MMR) spin lattice relaxation time (T1) are calculated for Cu sites in Yba2 Cu307. The calculations are based on the phenomenology model of Millis et al (1990) and the random phase approximation analysis of NMR by Bullet et. al (1990). The results are compared with experiments. The antiferomagnetic length is estimated to be 2.3 lattice constant at T= 100k and the total number of spins in the two dimensional plane is found to be temperature dependent. The finding make excitions mediated superconductivity conceivable [lsihara (1993)].

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11)

Unified Hamiltonian Model for Magnetism and Superconductivity in High-Tc Cuprate Systems

( page 121 – 135 of Vol 3 Namp Journals )

by G. C. Asomba
Department of Physics And Astronomy, University of Nigeria of Nigeria, Nsukka, Nigeria
and A. O. E Animalu
National Mathematical Center, Abuja, Nigeria

Abstract
A mean-field Hamiltonian model, applicable to the high-Tc cuprate oxide system, is represented, under the name paring t-model (PtM), which unifies some known Hamiltonian models for strong electron correlation (usually leading to magnetism) and the popular Bardeen-Cooper-schrieffer (BCS) model for electron pairing (leading to superconductivity). The PtM emphasizes electron kinetics as perhaps, the most important operative factor in the high–Tc cuprates. The analysis is based on a 4 x 4 matrix Green’s function method using the generalised pseudospin matrices of the type: Ap = p (p, = 0,1,2,3… where Ap are dummies for the Pauli , Dirac Gell-mann matrices) first introduced in the mapping of the novel pairing scheme in the multiple–band cuprates, by one of us, and some of the components recently used in the hadronic mechanics (Lie-isotopic) treatment of the Cooper pair by one of us. Some of the new results obtained for the normal and superconducting excitation energy, super-conducting energy gap, transition temperature and density of states, for the cuprates, have similarities with the corresponding results from experiment and the recent interlayer Josephson tunneling model by Anderson but may have advantages over the latter.

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12)

Possible Electronic Energy Structure of High-Tc Cuprates

( page 136 – 150 of Vol 3 Namp Journals )

by G. C. Asomba
Department of Physics and Astronomy, University 0f Nigeria, Nsukka, Nigeria

Abstract
Possible electronic energy structure of the high Tc cuprates is reported within the framework of a simple algebraic Green’s function analysis. The starting point is a two-band (d-p) restricted-hopping Hamiltonian in pseudospinor representation. The analysis leads to antiferromagnetic (af) Mott-Hubbard or charge transfer (ct) normal (undoped) state, depending on bandwidth and levels separation (~U). In our so-called t-model pairing of electrons, doped cuprates present as CT-assisted superconductors with AF exchange energetically forbidden. Approximate numerical results from the analysis are consistent with experiment and corresponding results form some other theories.
Keywords: two- band model, restricted hopping energy structure, algebraic Greens function, electronic levels separation, antiferromagentic normal state, CT-assisted superconductivity

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13)

Estimating the Stability of Some Alkalimetal Clusters Li, Li And Nana* using Local Spin Density Functional Formalism

( page 151 – 166 of Vol 3 Namp Journals )

by J. S. Ononiwu
Department of Physics, Federal University of Technology, Owerrri, Imo State, Nigeria

Abstract
We present a self–consistent local spin density approximation (LSDA) used in the density functional calculation of the stability of the alkali metal clusters Li,Li*, Na, Na* in the framework of a jellium-like model. Here for the neutral Li and Na clusters, the binding energy per atom obtained is about one fifth of the dissociation energy. Also, the results for the ionization potentials for and singly charged Li* and Na+ clusters enable us to understand and account for the enhanced stability of these alkali metal clusters.

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14)

Implementation of Equivalent Crystal Theory within a generalized embedded-Atom Method

( page 167 – 178 of Vol 3 Namp Journals )

by J. O. A. Idiodi
Department of Physics, University of Benin, Benin City, Nigeria
and E. Aghemenloh,
Department of Physics, Ambrose Alli University, Ekpoma, Nigeria

Abstract
This paper employs he concept of an equivalent crystal within a Generalized Embedded-Atom Method to calculate the (III) surface energies of four fcc metals – AL, Au, Pd and Pt. The results obtained for all four metals are found to be comparable to fist principles calculations and experimental data.

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15)

Discrete Eigenvalues of a Modified Pöschl-Teller Potential Hole using Semi-Classical Approximation

( page 179 – 192 of Vol 3 Namp Journals )

by K. J. Oyewumi,
Department of Pure and Applied Mathematics, Ladoke Akintoal Univeristy of Technology,
P. M. B. Ogbomoso, Oyo State, Nigeria.
and E. A. Bangudu,
Department of Mathematics, University of Ilorin, P. M. B. 1515, Ilorin, Kwara State, Nigeria.

Abstract
The use of a modified Pöschl-Teller potential hole is addressed using both semi-classical path integral and exact methods. The exact results of eigenvalues of a modified Pöschl-Teller hole is obtained on solving the one-dimentional Schrödinger equation for this potential hole analytically, which shows the accuracy of the semi-classical method. The approximate quantization rules (the well known Bohr-Somerfeld quantization conditions) are derived from the W.K.B.J formulae (solutions). The semi-classical method is then tested by the quantization of the quantum mechanical systems of the modified Pöschl-Teller potential hole, which practically gives the some results as using exact method.

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16)

Computation of the Kernel Function by inversion of resistivity field data from Schlumberger Configuration

( page 193 – 207 of Vol 3 Namp Journals )

by M. B. Asokhia, S.O. Azi, F. O. Onwuka and O. Ujuanbi,
Department of Physics, Edo State University, Ekpoma

Abstract
A major problem in geophysical investigations using electrical methods is the interpretation of results in terms of lithological variation with depth. Interpretation is commonly found by matching practical field curves with theoretically generated curves from resistivity kernel function. The kernel function cannot be measured in the field but has to be obtained from a transformation of measured apparent resistivities. Several kernel functions have been identified. The need to formulate an optimum kernel function leads to continued research on this subject. This work reviews major previous kernel functions in literature with their peculiar problems. Apparent resistivity value is then theoretically derived as an expression involving an integral over the kernel function, which contains all needed information about the present configuration of the earth. The integral equation is solved to get the kernel function. Theoretical curves generated with the kernel function were matched with practical curves from field data obtained in Owan West Local Government Edo State, Nigeria. The interpretation based on this kernel function agreed very satisfactorily with well logs in this area of Edo State.

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17)

Noise reduction and cancelling stationary sinusoidal noise in Seismic data acquisition in Atala prospect of River State

( page 208 – 221 of Vol 3 Namp Journals )

by J. C. Egbai,
Edo State University, Ekopma, Nigeria

Abstract
The process of noise reduction in seismic method of prospecting has brought about improvement in data quality as well as operational efficiency. For his research two primary approaches were used for reducing seismic noise to enhance desired reflections. The first is based on recoding arrangement that will cancel the unwanted signals before they are recorded in the field while the other is to process the data after they are recorded by appropriate filtering. Noise from the company’s (United Geophysical) plant was used to generate stationary sinusoidal noise. The seismic monitor was highly contaminated with sinusoidal noise. When this noise is large compared to seismic signals, it adversely affects prestack seismic processing and subsequent interpretation. A digital least-square filtering algorithm for cancelling stationary sinusoidal noise in the semi data leaving the signal.

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18)

Generalized Solutions to nonlinear parabolic equations.

( page 222– 233 of Vol 3 Namp Journals )

by E. O. Ifidon and E. O. Oghre
Department of Mathematics, University of Benin, Benin City, Nigeria.

Abstract
We consider the non-linear parabolic equation

where is a distribution with compact support or more generally, a generalized function associated with such a distribution. is a bounded open set in with smooth boundary and , is a positive integer. This equation arises often in chemical flow problems, gas dynamics and other physical processes and is known to have no weak solution in the classical distributional sense [1]. We show that the algebra of generalized functions G(Q) [2] provides a suitable setting for the construction of solutions to such a problem. We obtain existence, uniqueness as well as consistence results for the solutions to the problem using non-classical methods which involves the use of classical estimates and the induction hypothesis over the order of he differential operators which defines the elements of G(Q).

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19)

On the numerical simulation to Blasius’ Equation for Dimensionless Shear Stress

( page 234 – 248 of Vol 3 Namp Journals )

by A. S. Adekola
Department of Physics, Federal University of Technology, Akure, Ondo State, Nigeria.

Abstract
The fluid flow patterns were simulated numerically using fourth-order Runge Kutta scheme attributed to Gill. The numerical simulation of Blasius’ equation is aimed at investigating the behaviour of fluid flow under steady conditions and to estimate the dimensionless Shear Stress of flow. Carnaham et al (1959), Ologunleko and Adekola (1998) used the forth-order algorithm attributed to Kutta. Comparisons with their results showed that the procedure adopted by Carnahan was approximate while that of Ologunleko and Adekola was exact but the present numerical scheme has high level of convergence, which make it more appropriate whenever Laminar-boundary layer of a fluid is to be studied.

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20)

The Dynamic Analysis of an Elastic plate with point-moving load

( page 249 – 257 of Vol 3 Namp Journals )

by Y. M. Aiyesimi
Department of Mathematics and Computer Science, Federal University of Technology, Minna, Nigeria.

Abstract
This paper gives a mathematical analysis of the deflection profiles of an elastic plate resting on an viscoelastic foundation subject to the effect of a point load whose position at any time t is defined parametrically as where R is the radius of the orbit and is the circular frequency of the load (angular velocity). Since the plate itself has a natural frequency and the moving load constitute an external vibration as observed in the defining Equation 2.2 there arise the case of resonance. In this paper therefore, the author determines mathematically the vibrating conditions that give rise to the occurrence of his phenomena, which in actual fact is a menace to structures for which the modelled plate represents.

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21)

Numerical solution for a non-Boussinesque radiative flow in the Annulus of concentric rotating spheres

( page 258 – 274 of Vol 3 Namp Journals )

by Y. M. Aiyesimi
Department of Mathematics and Computer Science, Federal University of Technology, Minna, Nigeria.

Abstract
The thermal properties like the viscosity, conductivity and difussibility of certain fluid have been shown by experiments to vary with its thermal state like its temperature and pressure. For instance in Birds et al [1] the viscosity of gasses at low density has been found to vary almost directly with the square root of its absolute temperature whereas the viscosity of a pure liquid was shown to decrease exponentially with its absolute temperature. In most of the familiar researches carried out on fluid flow the analysis are based on the invariance of this properties. The results obtained therefore from such analyses re bound to be unreliable in view of the variance of the principles on which such analyses re based with real fluid. This paper therefore carry out a numerical investigation of the flow generated by a fluid whose viscosity, conductivity and difussibility vary with its absolute temperature according to a model in the annulus of rotating sphere. The results of this analysis is compared with the results obtained from Newtonian analysis (constant properties.)

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22)

A steady flow of fluid in an open rectangular container

( page 275 – 285 of Vol 3 Namp Journals )

by P. B. Shola,
Department of Mathematics, University of Ilorin, Ilorin, Nigeria.

Abstract
A steady slow flow of a viscous liquid in an open rectangular container is considered. The flow is driven by the base of the container, which moves steadily along is plane. The topside of the container is left open with the liquid in contact with the air above it. Consequently, the upper boundary of the flow is a free boundary and part of the unknown to be determined. Considering the inertial, gravitational and surface tension forces a numerical procedure for obtaining solutions for the cases when the capillary numbers are small is provided and the curves of the free boundaries obtained here presented for some flow parameters.

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23)

Phase plane analysis of liquid front moving through a hot porous rock

( page 286 – 289 of Vol 3 Namp Journals )

by R. O. Ayeni,
Department of Pure and Applied Mathematics,
Ladoke Akintola Univeristy of Technology, Ogbomoso, Nigeria.

Abstract
It is known that not geothermal reservoirs may have temperatures as high as 200 to 300 °C and in such reservoirs the water vapour may have pressures in the range of 1 – 30 atmospheres. In this work we show analytically how pressure runaway occurs.

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24)

On the Evolutions of the Ocean wave generated low frequency Seismic noise

( page 290– 298 of Vol 3 Namp Journals )

by E. O. Okeke, C. Adejayan
Department of Mathematics, Univeristy of Benin, Benin City, Nigeria
and V. E. Asor,
The Shell Petrolleum Development Company of Nigeria Limited, Warri

Abstract
The forward problem of ocean wave-seabed interaction in the shallow continental shelf is investigated. Consequently, we have examined the multi-layer effects of the transmission of acoustic wave through the layered medium. Thus, displacement components of the medium associated with the seismic events in a homogeneous elastic medium were compared with those oscillations in a multi-layered earth’s structure. There from, it is deduced that each type of medium appears to support acoustic waves trapped near the earth’s surface. However, in the multi-layered case, the drop in the acoustic wave energy in downward direction is more apparent and thus depict the effect of the wave refraction across the layers.

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25)

Criteria for unique solution of a radial porous medium combustion

( page 299 – 312 of Vol 3 Namp Journals )

by O.K. Koriko,
Department of Industrial Mathematics and Computer Science,
Federal University of Technology, Akure.

Abstract
The problem of finding conditions for a unique solution is considered. New criteria for a unique and global existence are found. These are achieved through numerical method.

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26)

On a family of methods for simultaneous inclusions of zeros of polynomial and analytic functions inside a simple smooth closed contour in the complex plane.

( page 313 – 322 of Vol 3 Namp Journals )

by S. E. Uwamusi
Department of Mathematics, Faculty of Science,
University of Benin, Benin City, Nigeria.

Abstract
A family of methods with k + 2 R-order which possesses high speed of convergence for the simultaneous determination of zeros of polynomial and analytic functions inside a simple smooth closed contour in the complex plane is considered. Neglecting terms involving analytic function in our method leads to the well-known method previously considered in [7]

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27)

The saturation of bean-excited ionospheric lower hybrid resonance through ion acceleration

( page 323 – 329 of Vol 3 Namp Journals )

by Salihu S. Duwa,
Department of Physics, Bayero University, Kano, Nigeria
and B. Chike-Obi,
Department of Physics, University of Ilorin, Nigeria.

Abstract
Electron beams which precipitate into the aurora along the earth’s magnetic field lines are responsible for the excitation of broadband electrostatic waves at heights less than 1500km, with an intensity peak near the lower hybrid frequency. It is argued that the lower hybrid wave become saturated by transferring energy to ambient ions, to produce an ion conic, which is a distribution with the ions concentrated on a cone in velocity space. The electron and ion populations are modelled, at the outset, as displaced and ordinary Maxwellians, respectively. The relaxation time of the electron beam and he rate of energy transfer from it are estimated from the nonlinear diffusion coefficient in the limits where Vd and Ve are the drift and the thermal speeds of the electrons.

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28)

Theoretical significance of field measurements of radioactive leaf and canopy temperatures

( page 330– 340 of Vol 3 Namp Journals )

by A. A. Olufayo
Department of Agricultural Engineering, Federal University of Technology, Akure, Ondo State,

Abstract
The significance of the measurement of leaf and canopy temperatures was demonstrated analytically from energy and radiative balance equations. Theoretical leaf and canopy temperature was shown to be related to water status of the crop and the difference between canopy and air temperatures was related to the vapour pressure deficit of the air, the net radiation and the wind. Experimental work showed that up to a difference of 50C was observed between well-watered and stressed treatments, which confirmed the theoretical relationships.

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29)

Remotely sensed crop canopy temperature, ambient relative humidity and air Temperature: Theoretical Analysis and Experimental verification

( page341– 349 of Vol 3 Namp Journals )

by A. A. Olufayo
Department of Agricultlural Engineering, Federal University of Technology, Akure, Ondo State.

Abstract
Recent advancement in infrared thermometry has permitted the measurement of leaf or vegetation canopy temperature without contact. The aim of this paper is to demonstrate from theoretical background the relationship between canopy temperature, relative humidity and air temperature. Field experimental data are presented to verify the theoretical relationships.

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30)

Sensitivity and error analysis of Blaney-Morin-Nigeria evapotranspiration model

( page 350 – 359 of Vol 3 Namp Journals )

by P. G. Oguntunde
Deparment of Agricultural Engineering,
Federal University of Technology, Akure, Nigeria.
F. I. Alao,
Department of Mathemtics and Compuer Science,
Federal University of Technology, Akure, Nigeria.
and
A. A. Olufayo,
Department of Agricultural Engineering,
Federal University of Technology, Akure, Nigeria.

Abstract
The response of Blaney-Morin-Nigeria model to errors in estimation of the input parameters of temperature, relative humidity and radiation ratio is examined. Direct response approach and application of partial derivatives method were used for the purpose. The results showed that a±4°C change in temperature caused about 10% change in evapotranspiration . The response of the model to a±15% variation in Humidity was 28% and a±15% change in radiation ratio alters by 15%. Based on the uncertainty of each measuring temperature, the overall performance of BMN model was affected by 7.5% for temperature, 11.4% for relative humidity and 7.5% radiation ratio. The implications of these results are discussed.

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31)

Analytical solutions of the Bloch equations for MRI flow dependent magnetization and signals with spatially varying Magnetic field

( page360 – 369 of Vol 3 Namp Journals )

by O. B. Awojoyogbe.
Department of Physics, Federal University of Technology
Minna, Niger State, Nigeria.

Abstract
Nuclear magnetic resonance (NMR) has been established as a powerful tool to study the structure of complex molecules. Molecular motion, rate processes and molecular interactions. Despite the tremendous theoretical and technical advanced improvement of this new medical diagnostics in many research laboratories around the world, there is a common belief however, that basic NMR properties of biological materials are still far from being fully understood and a great deal of further research is needed to clarify the quantitative and qualitative information in various NMR studies. An ideal approach to extract this useful information would be to find generalized solution in the Bloch equation, but this is obviously a difficult task. In this study we present a generalized analytical solution of the Bloch equation s for magnetic resonance imaging flow dependent magnetization and signal with spatially varying magnetic field.

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32)

An expression for Ez component of spatial non-uniform Electromagnetic source fields in low latitude.

( page 370 – 378 of Vol 3 Namp Journals )

by D. D. Abajingin and G. N. Obodi
Ondo State University, Ado Ekiti, Nigeria.

Abstract
In this presentation we obtained the expression for Ez component of non- uniform source fields in low latitude. The plots obtained both in space-frequency and space- time domains give a more accurate form than our earlier expression. The non- homogenous differential equation was reduced to Cauchy initial boundary values specified by functions defined as and . These functions are specified at plane t = 0

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33)

Potential distribution and focusing properties of an equidiameter co-axial cylindrical electrostatic lens

( page 379– 392 of Vol 3 Namp Journals )

by A. M. Awobode
Department of Physics, University of Ibadan, Nigeria
and O. M. Oni
Departments of Pure and Applied Physics,
Ladoke Akintola University of Technology
P. M. B. 4000, Ogbomoso, Nigeria

Abstract
An alternative method of derivation of the results of Read et al (1970) is presented. The values were obtained using a different parameterization of the potential function, and using numerical approach. The results were used to plot the equipotential lines, trace the electron ray path and determine the cardinal points of an equidiameter co- axial cylindrical electrostatic lens over a range of voltage ratio and lens separation. The cardinal points (f1 and f2) thus measured from the electron ray path showed a close approximation to the calculated value.

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34)

Electrostatic energy matrices for sub-configuration of ions in octahedral crystal field

( page 393 – 405 of Vol 3 Namp Journals )

by I. M. Mejeha
Department of Physics, Federal University of Technology,
Owerri, Imo State, Nigeria.

Abstract
In this paper, the problem of the interaction of the and 5d electrons of divalent samarium ions in crystalline environment is discussed within the framework of the Yanase-Kasuya coupling formalism and the Racah irreducible tensor operator techniques. Accordingly the reduced matrix elements of the symmetric many-electron double tensor operators of rank (1, k), k = 1, 2, … 6, between SL-coupled wave functions of the sub-configuration are calculated and presented. In additions the block coefficient on the electronic wave functions of the sub-configuration are also computed. With these the direct Coulomb and exchange matrices re computed and their elements expressed in terms of Slater-Condon parameters

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