Pusat Pengajian Sains Fizik - Tesis

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  • Publication
    Ultrasound Assisted Bismuth Coated Iron Oxide Nanoparticles For A Potential Dual-Modal Ct/Mr Imaging Contrast Media
    (2024-02)
    Braim, Farhank Saber
    In this study, ultrasound rapidly modified Fe3O4 NPs by coating their surface with Bi NPs, creating unique Fe3O4@Bi composite NPs for computed tomography (CT) scan and magnetic resonance imaging (MRI).
  • Publication
    Time Lapse (4d) Seismic Signal Detectability Improvement Using Co-Processing Technique On Carbonate Reservoirs
    (2023-11)
    Mohamed Mahgoub, Mohamed Abdelghany
    4D seismic studies are used to monitor the performance of hydrocarbon reservoirs during production or injection phases. Repeated 3D seismic surveys must be able to measure a 4D signal that can detect fluids substitution or pressure changes that may take place during reservoir production or injection of water or gas over a period of time. In practice, the seismic signal allied with such changes could be perceptible in clastic reservoirs whereas it could be negligible in heterogeneous carbonate reservoirs. Repeating 3D seismic surveys with the same acquisition geometry is usually difficult in the Middle East due to environmental changes (e.g., rough terrain, water currents, seasonal changes, and field production installations). Therefore, three oil and gas fields of offshore Abu Dhabi in the United Arab Emirates with scarce seismic acquisition repeatability have been selected for this study. In this study, the 4D seismic co-processing for the three case studies differs from the input data, whether it starts from the seismic field data or from different pre-processing and deconvolution, or whether it starts after the same deconvolution on base and monitor seismic surveys.
  • Publication
    Formulation Of A High-Fidelity Nuclear Fission Sites Convergence Detection Method In Monte Carlo Reactor Safety Assessments
    (2023-11)
    Chin, Ken Fui
    Monte Carlo (MC) neutron transport simulation is a widely used computational tool for assessing the safety of various nuclear technologies, including nuclear reactors. During the simulation, an initial guess of the neutron source distribution is required, and as several MC cycles are simulated, it converges to the true distribution. The outcomes from the initial cycles are discarded, and the outcomes from the subsequent cycles are accumulated to obtain a statistically meaningful result. Therefore, accurately identifying the convergence trend is crucial to prevent error accumulation from the initial guess. Traditional convergence diagnostic techniques rely on discretizing the problem geometry, and the selected meshing scheme heavily influences their performance and accuracy. This research formulated and refined a novel mesh-free convergence diagnostic indicator called Fourier fundamental mode coefficient (FFMC).
  • Publication
    Enhancement In Resistivity Resolution Based On Data Amalgamation Technique
    (2015-12)
    Bery, Andy Anderson
    The 2-d electrical resistivity imaging measured resistivity distribution at the subsurface. Improvement in 2-d resistivity data quality was carried out by the data levels amalgamation (dla) technique which is based on overlapping data levels with two different arrays combination. The first study objective is to develop the numerical comparative assessment for individual array and the dla technique of two different arrays. The second objective is to improve resolution using the dla technique on two different arrays. The final objective is to validate the dla technique of two different arrays. In order to achieve all three objectives, the study was carried out in three different phases. The first phase involved 2-d computerized models or namely synthetic models and a field model are presented. Five different synthetic models are created and used to investigate the imaging capabilities using four different arrays. In second phase, the numerical comparative assessment is introduced for the individual array and the dla technique. The two best and suitable arrays were determined based on the numerical comparative analysis results. In phase three, validation of the dla technique using two best and suitable arrays are applied to the actual field surveys. Based on the numerical comparative assessment for both 2-d computerized models and a field model, it shows that the dla technique of pole-dipole (p-d) and wenner- schlumberger (w-s) arrays are able to provide good data quality of image.
  • Publication
    The Effect Of Annealing On Random Lasing In Zinc Oxide Nanorods Grown By Chemical Bath Deposition
    (2019-04)
    Maad Tazri, Nur 'Izazi
    One dimensional ZnO nanostructure have been extensively studied due to its potential application in electronic and optoelectronic devices. The work presented here utilizes ZnO nanorods prepared by CBO method on pretreated glass substrate.