Browsing by Author "Akinyemi, M. L."
Now showing 1 - 12 of 12
- Results Per Page
- Sort Options
Item Machine Learning Projection in Performance Evaluation of Cloud Attenuation Prediction Models for Satellite Transmission Quality Improvement(2024) Adewusi, M. O.; Ometan, O. O.; Akinwumi, O. A.; Omotosho, V. T.; Akinyemi, M. L.Artificial satellite applications to information transmission remain of great importance now and in the foreseeable future. While machine learning is breaking research achievement records for good, the increase of political influence on scientific potentials needs to be managed cohesively by all for sustainability. The reliability of social and business interactions on communication infrastructure determines the technological advancement of every nation – developed or still underdeveloped. In the disclaimer notices of most financial institutions' transaction forms and mandatory customer business agreements, they declared that they are not liable for communication channel malfunction that may lead to transaction interruption, transmission blackout, and subsequent delay in their services. These prescribe effective hydrometeors attenuation margins determination periodically, from more accurate models – such as machine trained ones, to guarantee an increase in reliability of signal transmissions for every geographic location globally. Earlier research works established that required increases in transmission frequency for better efficiency are directly proportional to consequent hydrometeor attenuation on the signal, and that satellite communication unavailability in most tropical regions is above the allowed 1% outage percentage, significantly due to cloud attenuation contribution at satellite bands - which have been increasing consistently. The existence of clouds in tropical climates is almost perpetual, making cloud models all the more fundamental in tropical regions – which include Africa and not less than half of the rest of the world. The published new tropical cloud attenuation algorithm and its resulting new tropical cloud attenuation model (NTM) - derived from it, are hereby further analysed with respect to a wider frequency range. In the primary research of this work, data were collected from a spectrum analyzer, weather-link, and radiosonde equipment. The data were used to calculate values of cloud attenuation by each major existing cloud model in the signal propagation range of 12 to 50 GHz. The predicted cloud attenuation values were spectrally processed and analysed, resulting in the observation that the NTM’s predictions generally average the characteristics prediction values of existing models as shown by presented graphical outputs, though its differences in values relative to each of the other models are substantial in most cases, as either an increase or a reduction. Also, the predicted attenuation values by each of the cloud models converge increasingly direction-wise with frequency. The stated periodicity requirement above in these regards needs a machine learning approach to at least increase the periodicity of the result’s integrity and reliability by several tens of years, for every geographic location globally.Item The Influence of Some Atmospheric Phenomena on Total Ozone Concentration over the Tropics(Australian Journal of Basic and Applied Sciences) Akinyemi, M. L.Item Theoretical Study of Quantum Efficiency and Spectral Response of Solar Cells(7th International Conference on Science and Sustainable Development and Workshop, 2024) James, U. E.; Dim, C. C.; Akinyemi, M. L.; Ogunrinola, I. E.A theoretical study of Quantum Efficiency (QE) and Spectral Response (SR) of solar cells was done in order to suggest ways in which related parameters could be optimized for maximum conversion efficiency of solar cells. Secondary data for the base, emitter and total parameters of QE and SR were obtained. MATLAB was employed in plotting and analysing these data across different diffusion lengths. From the results obtained, it was observed that when the value of the Emitter Diffusion Length (EDL) was varied from 0.3µm to 0.5µm, the emitter and total values of QE increased by about 700% at wavelength 300nm – 400nm. In the case of SR, it was observed that when there was an increase in the Base Diffusion Length (BDL) from 20µm to 50µm, there was an increase of about 26% at wavelength 800nm – 900nm. A rise in the diffusion length was seen to increase both the QE and SR of the cell. Thus, it can be suggested that an increase in the emitter and base diffusion length of a solar cell leads to a decrease in the recombination charges in the cell, giving more time for the charge carriers to exit the cell.Item Total Ozone as a Stratospheric Indicator of Climate Variability Over West Africa(Academic Journals) Akinyemi, M. L.Item Wind Convolution and Ozone Distribution over NigeriaAkinyemi, M. L.