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A simple method for analyzing electrical earthing system is presented. The idea behind this research is to furnish the general public particularly in Ghana to understand the effectiveness of using low resistive materials to provide low resistance values for their earthing frameworks to protect lives and guarantee hardware security. Right now, proficiency of materials accessible for free, to be specific, Palm Kernel Oil Cake (PKOC) and Tyre ash, as conductive inlay material for decreasing earth terminal resistance was assessed. Earth mat 20-cm length and 10cm breath were covered with each refilling material with their exhibition contrasted with reference to the earth mat additionally covered at a similar location with raw sand, specifically, sandy gravel at a specific area in Ghana. The outcomes show that tyre ash gives a steady earth resistance in both dry and wet climate conditions and improves it significantly as compared to PKOC. The main purpose of evaluating these two local materials as a backfilling agent is to reduce the earth resistivity which in this study was achieved successfully after 3 months of monitoring.

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We present numerical simulation study of super-resolution imaging of closely spaced sub-wavelength size breast tumours with low cost microwave MIMO bowtie antenna array integrating with near-field planar multi-layered sub-wavelength patch (MLSWP) scatterers by using a monopole as the excitation source. The MLSWP scatterers, serving as transforming structures for the propagation of evanescent waves for sub-wavelength breast tumours imaging with far-field time reversal technique incorporating with bowtie antenna time reversal mirror, are investigated in this paper. The use of the MLSWP scatterers has enhanced the directivity and gain of the traditional monopole resulting in the enhanced scattering amplitudes of the tumour inclusions in the breast. The scattering intensity of the tumours has been enhanced as compared to imaging without the MLSWP scatterers. We propose a tumour imaging scheme using a bowtie antenna array with far-field electromagnetic time reversal for which tumours of sub-wavelength dimensions of 2 mm, 4 mm and 6 mm at sub-wavelength inter tumour distances have been imaged from our simple breast model with super-resolution operating at 2.45 GHz. This will greatly enhance the early imaging of breast tumours in the fight against breast cancer whiles attaining a cost effective biomedical imaging system since the antennas and MLSWP scatterers are low cost microwave components.