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Development requires new findings and innovative science to support. This research aims to study the simulation of soft ground improvement by comparing the soil strength after mixing with pozzolanic and fibrous additive such as Palm Oil Fuel Ash (POFA) and Palm Oil Fibre (POF) were chosen due to its redundancy found as industrial waste material. The soft soil sample collected was added with 0%, 5%, 10%, 15% and 20% percentage of additives by weight respectively. The soil sample used was from the soil that passed through sieve size of 0.425 mm. The data and analysis show that POF treated soil has a higher optimum moisture content and greater shear strength than the POFA treated soil.

The study presents application of an in-house software program to calculate image quality parameters of kV cone-beam CT (CBCT) system in radiotherapy. The parameters include uniformity, noise, contrast-to-noise ratio, CT number linearity, spatial resolution and geometric distortion as recommended in AAPM TG142 and TG179 quality assurance (QA) programme for image quality performance of kV CBCT. The computer algorithm packaged in the software program is developed using MATLAB (MathWorks, Natick, MA). The algorithm was optimised for two CT image quality phantoms, Catphan 600 (The Phantom Laboratory, Salem, NY) and CIRS 062QA (CIRS, Norfolk, VA). The phantoms were scanned with XVI CBCT system (Elekta AB, Stockholm, Sweden) using an optimised CT imaging protocol. The algorithm measures the image quality metrices from the corresponding image quality test patterns in the reconstructed CT images. The algorithm provides image quality parameters from both phantoms quantitatively. The software program allows the results to be exported and recorded in MS Excel for monitoring the performance trend of the image quality parameters. The software reduces measurement uncertainties from qualitative human observation of the test patterns.

The objective of this study is to quantitatively evaluate the image quality of a kV cone-beam CT-based IGRT system (Elekta, XVI) using two commercial CT image quality phantoms, Catphan-600 and CIRS-062QA. Both phantoms consist of similar image quality test modules (uniformity, CT linearity and spatial resolution) but each phantom has different diameter and test pattern design. Each test module was imaged separately using an optimised cone-beam CT imaging parameter. The quality metrics of the reconstructed images were analysed using algorithms developed with MatLab. The image uniformity and the spatial resolution measured with Catphan were of 4% and 40% greater respectively, compared to those measured with CIRS phantom. The differences were due to the beam scattering and hardening originated from the CIRS phantom holder. The contrast-to-noise ratio (CNR) values measured with CIRS phantom were at least 2% higher than that of Catphan. The diameter of CIRS phantom is smaller and resulted in lower beam attenuation. The quantitative image quality assessment algorithms developed for both phantoms provided a phantom-specific set of reference values for a cone-beam CT imaging system as recommended by AAPM TG-142. Further investigation will be performed to resolve beam hardening issue arising from the CIRS phantom holder.