Comparison of denoising methods for digital mammographic image

We compared effects of denoising methods on digital mammographic images. The denoising methods studied were an adaptive Wiener filter and low–pass Gaussian filter. The denoising methods were applied as an image preprocessing techniques before enhancement. The performance of image denoising methods are based on Mean Squared Error (MSE) and Peak Signal To Ratio (PSNR) values

Compton scrattering study using ludlum configuration for tissue-equivalent phantom material made from soy-lignin bonded Rhizophora spp. particleboard

Rhizophora spp. particleboards were prepared at approximately (20.0 × 20.0 × 1.0) cm3 and at 1.0 g·cm-3 target density. The mass attenuation coefficient of the soy-lignin bonded Rhizophora spp. particleboard was measured by Compton scattering using Ludlum configuration utilizing the Cesium-137 (137Cs). Monte Carlo (MC) GATE code was employed to simulate the scattering by using the same set-up. Compton scattering results from both experimental and simulation methods were compared with XCOM value of water. Half value layer (HVL) and mean free path (MFP) were calculated and analyzed. For Compton scattering method in comparison to XCOM value of water, both non-coated and coated samples showed a statistically non-significant value with p-value more than 0.05. The overall results suggested that the mass attenuation coefficient, HVL and MFP of soy-lignin bonded Rhizophora spp. particleboard based on Compton scattering study is within close agreement with XCOM value for water, exhibiting its potential as phantom materials

Assessment of Ge-doped optical fibres subjected to x-ray irradiation

We have reported the thermoluminescence (TL) response of five different diameters ∼120, 241, 362, 483, and 604 μm of 6 mol percent Ge-doped optical fibres. The perfomance of the Ge-doped optical fibre are compared with commercially available TLD-100 chips (LiF:Mg,Ti) in terms of their sensitivity and minimum detectable dose (MDD). The irradiation was performed using X-ray machine (Model ISO 'Narrow Spectrum Series') provided by the Malaysian Nuclear Agency (MNA) at 60 kV X-ray irradiation in low doses ranging from 1-10 mGy. The results show the linear TL dose response from the fibres up to 10 mGy. The smallest diameter of 120 pm optical fibre shows the highest TL dose response compared to above mentioned fibres. The minimum detectable dose (MDD) is 0.82, 0.20, 0.14, 0.08, and 0.13 mGy for Ge-doped with diameters of 120, 241, 362, 483 and 604 μm. All TL materials show the MDD value within the delivered dose 0.01-1.00 mGy subjected to x-ray irradiation. The Ge-doped fibre with diameter of 483 pm was matched the MDD value of TLD-100 chips that equivalent to 0.08 mGy at the same irradiation. We have observed that among the five different diameters of optical fibre, 120 μm shows the best results and its better response than TLD-100 chips (by a factor of 5). The linear response at low dose levels makes this optical fibre most suitable for medical applicatio

Thermoluminescent response of single mode optical fibre to x-ray irradiation

We present the characteristics of the thermoluminescence (TL) response of single mode optical fibre (SMF) subjected to 30 and 70 kV x-ray irradiation. The TL responses are compared with commercially available TLD-100 (rod types). The SMF and TLD-100 were irradiated with x-ray source by using X-rays Generator model Phillips MG 165 located at Malaysian Nuclear Agency. The SMF and TLD-100 show linear dose response subjected to 30 and 70 kV x-ray irradiation. The SMF shows TL response by 10 times and 8 times greater than TLD-100 for the above-mentioned energies. The TL sensitivity characteristics of SMF show promising results to be introduced as a TL dosimeter material. The SMF could be used in several applications in the fields of medicine, industry, and research purposes