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- PublicationWater Rights Ownership In Sultanate Of Oman: A Case Study On The Aflāj Institution In Northern Oman(2024-03)Using the ancient aflāj (singular falāj) system in Sultanate of Oman as a case study, this thesis investigates the Islamic water rights ownership and institution. This was conducted by analyzing the relationship of the physical water extraction variation among the three aflāj types in Oman and the development of water right types and the Islamic equitable principles/institutions. In literature many principles concerning water management and administration have been discussed. The most used one, in most Islamic studies, is how to manage water (as a natural gift) in relation with what Allah almighty given natural resource (also known as ecosystem) and human interaction. However, the focus of this thesis to fulfil the gap in our knowledge in how to provide a legal recognition of water rights ownership and institution. In fact, a guiding tool using Oakerson operational rule/institution which is considered as soft constrain for two main reasons: 1) decision making made operative only through human knowledge, choice, and action 2) rules found in decision making exist entirely in ream language (whether written or unwritten). It is these written and unwritten rules that have been applied in describing aflāj historical institutional (which researcher called Islamic equitable principles) and confirms with revealed information found within aflāj communities in Oman. In addition, Islamic equitable principles have been used to avoid confusion with another Islamic term known as uşūl al-fiĝh or jurisprudences.
- PublicationLived Experiences Of Left-behind Children In Henan Province, China(2024-08)Since China’s reform and opening up, there has been a significant migration of surplus labourers from rural to urban areas. As a result, a growing population of children has been left behind in rural settings. These children face educational and psychological challenges that have emerged as important social issues. This study aims to explore the main challenges faced by these left-behind children, examine their coping strategies, and identify their specific needs. Additionally, the study seeks to develop an intervention model to improve their well-being. Conducted in Zhoukou City, Henan Province, the research focused on the care services provided for left-behind children. This study utilizes qualitative research methodology and employs the in-depth interview technique to gather data. Twenty-five (25) left-behind children were interviewed to understand their challenges, coping strategies, and specific needs. The study found disparities in living conditions and familial environments between left-behind children and those who were not left behind, contributing to the health vulnerabilities of left-behind children. Key findings include reduced interaction with parents, difficulties in forming interpersonal relationships, academic performance challenges, and the need for life skills acquisition. Left-behind children employ various coping mechanisms, such as recreational activities, emotional recalibration, seeking support, and taking proactive initiatives. Additionally, the study identified the needs of left-behind children, including the implementation of social work service programs, family care and support, educational engagement, community development and services, as well as national financial and policy support.
- PublicationFault detection of electrical motor based on thermal imaging and machine learning(2023-08)Faults could occur on electrical motor due to various reasons, and an early motor fault detection system helps prevent interruption in service and financial losses. However, the current practice of manual fault inspection and preventive maintenance is time consuming, and it may not be effective. Thus, motor fault diagnosis using thermal imaging technique has been on the rise in recent years. To further improve the effectiveness and to automate fault detection using thermal imaging, artificial intelligence (AI) can be employed. Hence, in this project, an electrical motor fault detection system based on thermal imaging and machine learning (ML) technique was developed. Transfer learning (TL) approach using pre-trained convolutional neural networks (CNNs) was used. The CNN was trained to learn the features extracted from the thermal images of a faulty and a healthy motor and use them to diagnose the condition of the motor. Various hyperparameters were configured for network training to obtain the best results. Furthermore, performance analysis was conducted and discussed to evaluate the credibility and reliability of the trained network. A Graphical User Interface (GUI) was then created to ease the user in using the proposed fault detection system by just supplying the thermal images of a test motor to the GUI application for fault diagnosis. The evaluation results showed that GoogLeNet gives the best detection performance with both the mini-batch and the validation accuracy achieving a 100%, and both the losses were low as well, at 0.0015 and 0.0001 respectively. Thus, the final trained network based on GoogLeNet was used in the GUI for the implementation of the proposed motor fault detection system. In conclusion, the aim for implementing a fault detection system and GUI, through the use of thermal images and machine learning was achieved.
- PublicationExplainable artificial intelligence for signature verification system(2023-10)In recent years, the use of personal identity, such as signatures, as a means of authentication has gained significant attention. There are some concerns arise due to the potential for signature forgery and leading to the development of signature verification systems to determine the authenticity of signatures. The lack of understanding behind the AI and DL can erode trust in the tools as incorrect or biased decisions made. The application of Explainable Artificial Intelligence (XAI) methods in signature verification systems can address these concerns by providing insights into the decision-making process and enhancing the trustworthiness and reliability of the system. This research aims to explore and evaluate various explanation models to improve the interpretability and performance of signature verification systems. Furthermore, this research seeks to identify the specific aspects that users and developers focus on when considering explanations generated by these models. Moreover, this research aims to develop a new explanation model by combining the strengths of two widely used methods, LIME and Grad-CAM. The experiment is conducted through MATLAB using package known as Deep Learning Toolbox. The explanation evaluates through the respond of 18 respondents in four aspects, understandability, interpretability, accuracy and usefulness. The survey is also used to identify the evaluation aspect that are focused by users and developers. In addition, a new explanation model is developed through the combination of “scoremap” of LIME and Grad-CAM. Preliminary findings indicate that the Grad-CAM method demonstrates better performance from the user's perspective, while developers tend to prefer the LIME method. By leveraging the strengths of both approaches, the new explanation model achieves an impressive increase in understandability, interpretability, accuracy, and usefulness.
- PublicationEvaluation of isolated type multilevel inverter with different DC source selection scheme(2023-07)Multilevel inverters (MLI) play a major role in various power applications in converting direct current to alternating current for a power system. The ideal output voltage waveform should be a perfect sine wave. In practical, a real inverter will produce output voltage waveform which contains harmonics that are not acceptable for high power applications. Harmonics cause current and voltage waveforms to be distorted, resulting in power system degradation. To date, reducing the total harmonics distortion (THD) is always the main objective to conduct the research regarding the multilevel inverters, especially when the inverters are applied in renewable energy application. Therefore, the simulation testing of this project will focus on the total harmonic distortion value of the system. The proposed multilevel inverter in this research is asymmetrical multilevel inverter with trinary sequence. The targeted number of output levels are 5-L, 7-L and 9-L. This research is aimed to analyze the proposed topologies from the aspects of inverter power ratio, total harmonic distortion level and power contribution of DC voltage source in different DC source scheme. The switching signals are generated using a low frequency modulation technique where the switching angles are pre-calculated using derived mathematical equations. To evaluate the performance of the topology, linear load tests are conducted to ensure proper operation of the proposed topology in reference to theoretical analysis with MATLAB Simulink software. Based on simulation result, the THD values of the 5-L waveforms are the highest, followed by the 7-L waveforms and the lowest THD are measured on the 9-L waveforms. Under RL loads, the current waveforms show much lower THD readings since they are filtered by the inductive loads. The RL filtering effect causes the current waveforms to lost the stepped pattern which explains their smoother waveforms. The results show the high power ratio is averagely achieving 95% and above, indicating the reliability of the system. From DC source power contribution aspect, it is concluded that high power source is required to produce higher number of levels in MLI inverter. In short, the research outcome shows the topology with different DC source configuration is capable of generating high number of output levels with low number of total components. The individual current harmonics are also in accordance to the IEC/EN 61000-3-2 standard. Hence, this topology has great potential to be developed for real applications since the production cost is expected to be lower than the other topologies.
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- ItemAn Investigation Of The Neuroprotective Effects Of Palm Vitamin E Tocotrienols Using White Matter Lesions As The Human Study Model(Universiti Sains Malaysia, 2014-09)A study was conducted to evaluate the neuroprotective activity of mixed tocotrienols using human volunteers with white matter lesion (WML). WMLs are regarded as manifestations of cerebral small vessel disease. Initially, the anti atherogenic effect of mixed tocotrienols was also evaluated in mildly hypercholesterolemic volunteers via imaging the carotid arteries using Magnetic Resonance Angiography (MRA). Of the first 50 consecutive volunteers who undergone the carotid artery imaging, none of them were detected having carotid artery stenosis and hence this part of the study was discontinued. In the next phase of the study, the prevalence of white matter lesion (WML) in a local hypercholesterolemic population in north –west peninsular Malaysia was determined. Of the 350 research volunteers who were imaged, 161 (46%) of them had WMLs, of which 65 (18.6%) were males and 96 (27.4%) females. The study also demonstrated that the chances of developing WMLs doubled (30.6%) in the age group of above 50 compared to 15.4% in the age group of below 50. In the neuroprotective part of the study, a randomized double-blind placebo-controlled trial was conducted. Volunteers recruited were ≥ 35 years with cardiovascular risk factors and undergo Magnetic Resonance Imaging (MRI) of the brain. They were categorized as WML positive (MRI +ve) if they were present with WML at baseline. Volunteers without WMLs at baseline were classified as (MRI -ve). In the MRI –ve cohort, 120 volunteers were randomized to receive either 200 mg mixed tocotrienols or placebo twice daily and were followed up for 1 year. Out of 113 volunteers who completed the study, 19 in the mixed tocotrienols and 9 in the placebo group developed new WMLs. However, the mean volume of the WMLs developed after 1 year was lesser in the mixed tocotrienol treated group (8%) compared to placebo (47%) with a statistical significance of p = 0.048. In the final part of the study, 121 volunteers with MRI confirmed WMLs (MRI +ve) were randomized to receive 200 mg mixed tocotrienols or placebo twice daily and were followed up for 2 years. According to per protocol (88 volunteers) and intention-to-treat (121 volunteers) analyses, the mean WML volume of the placebo group increased after 2 years, whereas that of the mixed tocotrienol supplemented group remained essentially unchanged. The mean WML volume change between the two groups was not significantly different (p = 0.150) at the end of 1 year but was significant at the end of 2 years for both per protocol and intention-to-treat analyses (p = 0.019 and p = 0.018). Thus, the present study found that mixed tocotrienols can attenuate the progression of WMLs.
- PublicationPembangunan Dan Keberkesanan Modul B-geo Untuk Topik Pembezaan Dalam Kalangan Pelajar Tingkatan Empat Di Kedah(2022-01)Kajian ini ialah kajian pembangunan dan keberkesanan Modul B-Geo bagi meningkatkan kefahaman konseptual, kebolehan penyelesaian masalah, efikasi kendiri dan mengurangkan kebimbangan belajar Matematik Tambahan dalam Topik Pembezaan dalam kalangan pelajar sekolah menengah luar bandar. Kajian ini menggunakan reka bentuk Expert Judgement Approach bagi pembangunan Modul B-Geo dan reka bentuk Kuasi Eksperimental bagi melihat keberkesanan Modul B-Geo. Seramai 118 orang pelajar dan enam orang guru Matematik Tambahan dari sekolah menengah luar bandar yang terlibat dalam sampel kajian ini. Kumpulan eksperimen (n=60) adalah kumpulan yang menerima rawatan menggunakan Pendekatan Pengajaran Berasaskan Otak dengan Integrasi Perisian GeoGebra, manakala kumpulan kawalan (n=58) adalah kumpulan yang menerima rawatan menggunakan Pendekatan Pengajaran Konvensional (P ICT). Kajian keberkesanan dimulakan dengan ujian pra dan soal selidik pra. Setelah PdP dilaksanakan terhadap kedua-dua kumpulan selama 10 minggu, ujian pasca dan soal selidik pasca diberikan kepada pelajar. Tiga jenis instrumen kajian digunakan bagi mendapatkan data kuantitatif: Ujian Kefahaman Konseptual Topik Pembezaan (UKKTP), Ujian Penyelesaian Masalah Topik Pembezaan (UPMTP) dan Soal Selidik Efikasi Kendiri dan Kebimbangan Belajar Topik Pembezaan (SSEKK).
- ItemEffects Of Operational Factors On Biodegradation Of Phenol And P-Nitrophenol By Suspended And Immobilized Activated Sludge(Universiti Sains Malaysia, 2020-05)The presence of phenolic compounds in industrial effluents give rise to serious environmental problems owing to their high toxicity and bioaccumulation rate. This study aims to investigate the efficacy and kinetics of aerobic biodegradations of phenol and p-nitrophenol (PNP), respectively, by suspended and immobilized activated sludge at different operational conditions
- PublicationFactors Influencing The Adoption Of Internet Of Things For Home Security In Dhaka Households(2023-05)Globally, burglary crimes in some countries are effectively minimized by using advanced security technology supported by the Internet of Things (IoT). However, these crimes have caused rising concerns among residents in Dhaka. Despite the implementation of appropriate rules and technology development, IoT adoption in Bangladesh remains relatively low. Therefore, it is imperative to determine the factors that influence the intention to adopt IoT for home security. Accordingly, the Protection Motivation Theory (PMT) and Attitude-Social Influence-Self-Efficacy model (ASE) are integrated along with two moderating variables, personal innovativeness, and perceived trust to address the research objectives. This research implements a quantitative approach to analyze the primary data of 348 participants. Based on the findings, perceived severity, perceived vulnerability, response efficacy, response cost, and attitude are factors that impact the intention to adopt IoT with a variance of 34.9%. Moreover, the R2 and Q2 are improved respectively, due to the inclusion of personal innovativeness and perceived trust as moderators. Personal innovativeness positively moderates the relationships between response efficacy–intention, and self-efficacy–intention, and negatively moderates the attitude–intention relationship.
- PublicationExperimental and computational study on load carrying capacity of load bearing plain walls for buildings(2021-12-01)Reinforced concrete wall is a common structural element used as load resisting element in structures. Other than load resistance, they also serve as space enclosing wallstructures. This study focuses on concrete walls with less than 0.4% of compression reinforcement, called plain walls or ordinary concrete walls (BS 8110-1:1997), which are traditionally used as non-structural member in frame buildings. The design formulas for axial capacity of plain walls in BS 8110-97 neglect the contribution from the small percentage compression reinforcement. Taking advantage of progress made in concrete technology, plain wall is believed to provide alternative load bearing structural system due to the ease of using B.R.C mesh as reinforcement and economy due to relatively lower quantity of steel needed for construction in comparison with conventional reinforced concrete walls. The later point is critical for regions or countries where steel for construction needs to be imported. This study was carried out with the aim of investigating the influence of the low ratio of reinforcement on the behavior of plain walls. The possibility of adopting structural system using plain walls for tall buildings was also explored. Experiments were carried out to examine the effect of the arrangement of reinforcement - one layer, two layers, two layers with short hooks and two layers with long hooks, on behavior of plain wall specimens. A total of 40 plain wall specimens measuring 1600 mm (height) × 540 mm (width) × 106 mm (thickness) cast with 0.3% compression reinforcement were tested under axial load with three eccentricities of 3 mm, 15 mm and 30 mm (Group A – 20 specimens) and axial load with maximum eccentricity of half wall thickness 53 mm (Group B – 20 specimens). Concrete mix design with characteristic strength less than 20 MPa (actual strengths achieved were 16 MPa and 18 MPa) was used in the casting of the wall specimens. Deformation pattern, failure load and the associated mode, load-deflection behavior and strains in concrete and steel were recorded. Comparison of failure load with prediction based on BS8110-1:1997 was also made. A modified formula for predicting the axial capacity of plain wall considering the contribution of reinforcement was proposed. Simulation of plain wall behavior under axial load was also carried out using ANSYS. The outcome from the simulation work was used to obtain information about possible capacity of actual scale plain wall in buildings. Analysis and design using ETABS on series of models of tall buildings with typical floor layout of an actual project were carried out with the aim of determining the maximum number of storey possible with appropriately arranged plain walls as the load resistance system. Aspects of length of wall, shape of wall (L-shape vs straight shape) and symmetry of layout were variables considered in the models. Three different sets of concrete strength were considered: 25 MPa, 25+40 MPa(40 MPa to lower half and 25 MPa to upper half of building) and 40 MPa. Results of experiments showed significance difference in failure load relative to the predicted axial capacity using BS 8110-1:1997 in the range of 1.78 to 3.56 for Group A specimens depending on the eccentricity of load. Comparison for Group B specimens was not possible due to limitation of the formula in BS 8110-1:1997. Effect of the two layers of reinforcement in comparison with single layer on axial capacity was found to be more significant for Group B specimens which failed due to excessive bending in the top portion of the wall specimen. However, the effect was less significant for specimens in Group A. Provision of hooks did not show any significant contribution to increase the axial capacity for both Group A and B specimens. The proposed modified formula for the prediction of axial capacity of plain wall yielded better prediction when compared to the experimental results. Simulation results using ANSYS showed good agreement with the experimental results. Outcome of analysis and design using ETABS showed that the maximum number of storey possible for tall buildings with the use of plain walls as structural system is 15 storey with 25 MPa concrete. The maximum number of storey may be increased to 25 with concrete strength (25+40) MPa and 40 MPa if plain walls of appropriate length and combination use with L-shape walls were considered.Symmetrical layout of plain walls shows the best performance with the possibility of 25storey (with 40 MPa concrete) with relatively lower wall Demand/Capacity (D/C) ratios for the walls. This study has shown that compression reinforcement in plain wall contributed to the axial capacity of the plain wall. The outcome of this study has provided important information about the potential of plain walls with reinforcement ratio less than 0.4% to be used as load bearing members. Further study using full scale plain walls should be carried out in order to take more advantage of the potential of plain walls.