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Non-Relativistic Treatment of a Generalized Inverse Quadratic Yukawa Potential

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Chinese Physics Letters 2017年第11期34卷 1-5页

作者： Oluwatimilehin oluwadare Kayode Oyewumi Department of Physics Federal University Oye-EkitiEkiti StateNigeria Department of Physics University of IlorinKwara StateNigeria

A bound state solution is a quantum state solution of a particle subjected to a potential such that the particle＇s energy is less than the potential at both negative and positive infinity. The particle＇s energy may also be negative as the potential approaches zero at infinity. It is characterized by the discretized eigenvalues and eigenfunctions, which contain all the necessary information regarding the quantum systems under consideration. The bound state problems need to be extended using a more precise method and approximation scheme. This study focuses on the non-relativistic bound state solutions to the generalized inverse quadratic Yukawa potential. The expression for the non-relativistic energy eigenvalues and radial eigenfunctions are derived using proper quantization rule and formula method, respectively. The results reveal that both the ground and first excited energy eigenvalues depend largely on the angular momentum numbers, screening parameters, reduced mass, and the potential depth. The energy eigenvalues, angular momentum numbers, screening parameters, reduced mass, and the potential depth or potential coupling strength determine the nature of bound state of quantum particles. The explored model is also suitable for explaining both the bound and continuum states of quantum systems.

关键词： In Non-Relativistic Treatment of a Generalized Inverse Quadratic Yukawa Potential

Assessment of GNSS zenith tropospheric delay responses to atmospheric variables derived from ERA5 data over Nigeria

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Satellite Navigation 2023年第1期4卷 167-182,I0005页

作者： Ifechukwu Ugochukwu Nzelibe Herbert Tata Timothy oluwadare Idowu Department of Surveying and Geoinformatics Federal University of Technology AkureAkureNigeria

Tropospheric delay is a major error caused by atmospheric refraction in Global Navigation Satellite System(GNSS)*** study evaluates the potential of the European Centre for Medium-range Weather Forecast(ECMWF)Reanalysis 5(ERA5)atmospheric variables in estimating the Zenith Tropospheric Delay(ZTD).Linear regression models(LRM)are applied to estimate ZTD with the ERA5 atmospheric *** ZTD are also estimated using standard ZTD models based on ERA5 and Global Pressure and Temperature 3(GPT3)atmospheric *** ZTD estimates are evaluated using the data collected from the permanent GNSS continuously operating reference stations in the Nigerian *** results reveal that the Zenith Hydrostatic Delay(ZHD)from the LRM and the Saastamoinien model using ERA5 surface pressure are of identical accuracy,having a Root Mean Square(RMS)error of 2.3 mm while the GPT3-ZHD has an RMS of 3.4 *** the Zenith Wet Delay(ZWD)component,the best estimates are derived using ERA5 Precipitable Water Vapour(PWV).These include the ZWD derived by the LRM having an average RMS of 20.9 mm and Bevis equation having RMS of 21.1 mm and 21.0 mm for global and local weighted mean temperatures,*** evaluation of GPT3-ZWD estimates gives RMS of 45.8 *** study has provided a valuable insight into the application of ERA5 data for ZTD *** line with the fndings of the study,the ERA5 atmospheric variables are recommended for improving the accuracy in ZTD estimation,required for GNSS positioning.

关键词： ECMWF reanalysis 5(ERA5) Global navigation satellite systems(GNSS) Global pressure and temperature 3(GPT3) Modelling Nigeria Zenith tropospheric delay(ZTD)

Reflection and Transmission Coefficients of the Symmetric Barrier-Type Shifted Deng–Fan Potential

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Communications in Theoretical Physics 2017年第10期67卷 412-416页

作者： Oluwatimilehin Joshua oluwadare Kayode John Oyewumi Karl-Eric Thylwe Somayyeh Hassanabadi Department of Physics Federal University Oye-Ekiti Theoretical Physics Section Department of Physics University of Ilorin KTH-Mechanics Royal Institute of Technology Physics Department Semnan University

By applying continuity and boundary conditions, the reflection and transmission coefficients of one- dimensional time-independent Schr6dinger equation with a symmetric barrier-type shifted Deng-Fan potential are ob- tained and discussed. The numerical and graphical results are very sufficient, accurate and consistent with the conser- vation of probability.

关键词： SchrSdinger equation symmetric barrier-type shifted Deng-Fan potential transmission and re-flection coefficients

Semi-Relativistic Reflection and Transmission Coefficients for Two Spinless Particles Separated by a Rectangular-Shaped Potential Barrier

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Communications in Theoretical Physics 2016年第10期65卷 389-395页

作者： K.E.Thylwe O.J.oluwadare K.J.Oyewumi KTH-Mechanics Royal institute of Technology Department of Physics Federal University Oye-Ekiti Theoretical Physics Section Department of PhysicsUniversity of Ilorin

A generalized Schr¨odinger approximation,due to Ikhdair & Sever,of the semi-relativistic two-body problem with a rectangular barrier in(1+1) dimensions is compared with exact *** and approximate transmission and reflection coefficients are obtained in terms of local wave *** approximate transmission and reflection coefficients turn out to be surprisingly accurate in an energy range |∈-V0| < 2μc^2,where μ is the reduced mass,∈ the scattering energy,and V_0 the barrier top *** approximate wave numbers are less accurate.

关键词： two-body relativistic equation rectangular barrier transmission 1+1D relativistic scattering semi-relativistic approximation spinless Salpeter equation

Non-Relativistic Phase Shifts for Scattering on Generalized Radial Yukawa Potentials

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Communications in Theoretical Physics 2016年第4期65卷 434-440页

作者： O.J.oluwadare K.E.Thylwe K.J.Oyewumi Department of Physics Federal University Oye-Ekiti KTH-Mechanics Royal institute of Technology Theoretical Physics Section Department of PhysicsUniversity of Ilorin

Non-relativistic phase shifts for a generalized Yukawa potential V(r) =-V_0( e^(-αr)/r)-V_1( e^(-2αr)/r^2) are studied by the amplitude-phase method and by a frequently used analytic method based on a Pekeris-type approximation of power-law potential *** variations of V_1 seem to have marginal effects on the effective potential and on exact phase ***,as pointed out in this study,a Pekeris-type approximation in scattering applications often implies serious distortions of both effective potentials and phase *** Pekeris-type based analytic approximation in this study seems to give low-quality scattering results for this model potential at low energies.

关键词： quantum mechanics scattering partial waves resonances

Between-Tree and Within-Tree Variation in Specific Gravity and Extractive Content in the Wood of Stercufia setigera Del. Grown in Nigeria

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Journal of Agricultural Science and Technology(B) 2011年第7期1卷 1075-1085页

作者： A. O. oluwadare M. B. Ogunleye Department of Forest Resources Management University of lbadan P.O. Box 9054 U.I. Post Office lbadan 200005 Nigeria College of Forestry Forestry Research Institute of Nigeria Jericho P.M.B. 5087 Jericho Hill Ibadan 200005 Nigeria

Variations of wood specific gravity and extractive contents from pith to bark and from base to the top of tree were investigated in a 14-year-old commercial pulpwood species Sterculia setigera Del. Growing in savanna zone in Nigeria. Tree mean specific gravity averaged 0.37; wood at the base had significant higher specific gravity than those at the top while it increased from pith to bark. For extractive content mean value was 1.20% for wood and 1.72% for bark; i[t varied significantly between trees and from base of the tree to the top and from pith to the bark. Extractive content at the butt and breast height is more than double of the value at the top of the tree. The high extractive content at the base is similar to high specific gravity observed for wood samples from the base. Extractive content of the bast was significantly higher than that of the wood. The low specific gravity show possible suitability of the species for paper making in Nigerian paper mills. The wood of Sterculia setigera showed a significant variation between- and within-trees in the two properties considered, though the wood is light with low extractive content; it is however a potential raw material for large scale pulpwood production in Nigeria.

关键词： Specific gravity extractive content patterns of variation Sterculia setigera.

Exergoeconomic Evaluation and Optimization of Dual Pressure Organic Rankine Cycle (ORC) for Geothermal Heat Source Utilization

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Journal of Power and Energy Engineering 2021年第9期9卷 19-40页

作者： Dodeye Igbong Oku Nyong James Enyia Benjamin oluwadare Mafel Obhua Department of Mechanical Engineering Cross River University of Technology Calabar Nigeria Department of Mechanical Engineering Ekiti State University Ado Ekiti Nigeria Department of Mechanical Engineering Nigeria Maritime University Okerenkoko Nigeria

In the present study, a dual-pressure organic Rankine cycle (DORC) driven by geothermal hot water for electricity production is developed, investigated and optimized from the energy, exergy and exergoeconomic viewpoint. A parametric study is conducted to determine the effect of high-stage pressure and low-stage pressure variation on the system thermodynamic and exergoeconomic performance. The DORC is further optimized to obtain maximum exergy efficiency optimized design (EEOD case) and minimum product cost optimized design (PCOD case). The exergy efficiency and unit cost of power produced for the optimization of EEOD case and PCOD case are 33.03% and 3.059 cent/kWh, which are 0.3% and 17.4% improvement over base case, respectively. The PCOD case proved to be the best, with respect to minimum unit cost of power produced and net power output over the base case and EEOD case.

关键词： Geothermal Water Dual Pressure Organic Rankine Cycle Exergoeconomic Factor Optimization

Automatic Table Recognition and Extraction from Heterogeneous Documents

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Journal of Computer and Communications 2015年第12期3卷 100-110页

作者： Florence Folake Babatunde Bolanle Adefowoke Ojokoh Samuel Adebayo oluwadare Department of Computer Science Osun State College of Education Ila-Orangun Nigeria Department of Computer Science Federal University of Technology Akure Nigeria

This paper examines automatic recognition and extraction of tables from a large collection of het-erogeneous documents. The heterogeneous documents are initially pre-processed and converted to HTML codes, after which an algorithm recognises the table portion of the documents. Hidden Markov Model (HMM) is then applied to the HTML code in order to extract the tables. The model was trained and tested with five hundred and twenty six self-generated tables (three hundred and twenty-one (321) tables for training and two hundred and five (205) tables for testing). Viterbi algorithm was implemented for the testing part. The system was evaluated in terms of accuracy, precision, recall and f-measure. The overall evaluation results show 88.8% accuracy, 96.8% precision, 91.7% recall and 88.8% F-measure revealing that the method is good at solving the problem of table extraction.

关键词： Hidden Markov Model Table Recognition and Extraction Hypertext Markup Language Heterogeneous Documents

Effect of Silicon Content and Shake-Out Time on Hardness and Grain Size Properties of GL 250 Cast Iron

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Journal of Minerals and Materials Characterization and Engineering 2011年第3期10卷 257-266页

作者： P. Atanda G. oluwadare O. Oluwole Industrial Chemistry Department Bells University Nigeria. Materials Science and Engineering Dept. Obafemi Awolowo University Nigeria Mechanical Engineering Dpartment University of Ibadan Nigeria

The properties of cast iron grade GL 250 are dependent on the microstructures developed during casting. These microstructures are in turn dependent on the composition of the alloy, type of mould and other numerous casting practice variables such as shake-out time, pouring temperature, mould ambient conditions and inoculating technique. In this work, the effect of silicon content and shake-out time on the grain size (GS) and hardness properties of GL 250 cast iron was studied using a pouring temperature of 1400℃ and sand mould casting. Using charge materials consisting of pig iron and other additives, GL 250 castings containing silicon contents of 1.7, 2.1 and 2.7% were casted using a constant pouring temperature of 1400℃, molding sand of specified properties and ambient mould temperature of 32℃. Results showed that type A flake type was obtained at 30mins shakeout time for all samples for the C.I composition under study. Increasing shake-out time decreased hardness and increased carbide grain size. Increasing silicon content was observed to increase grain size and reduce free graphite but with resultant decrease in hardness. Two mathematical relationships were derived. One related grain-size to silicon content and shakeout time while the second related Brinnel Hardness to Silicon content and shake-out time. They are: Grain Size=0.40 Si+0.17Shake-out Time-0.15 and BHN=-60.53Si-7.15Shake-out Time+329.35 at 1400℃ pouring temperature in a molding sand of specified properties and sand mould ambient temperature of 32℃.

关键词： Shake-out time Silicon content Hardness Grain-Size GL 250 C.I