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- PublicationDesign, development and fabrication of autonomous surface vessel (ASV) shallow water mapping application(2024-07)This thesis explores the development and application of Autonomous Surface Vehi cles (ASVs) as advanced tools in marine technology, specifically addressing the critical need for accurate underwater terrain mapping. Traditional methods often fail in com plex, shallow water environments, impeding scientific, environmental, and maritime operations. By integrating ASVs with advanced sonar systems, this research aims to enhance mapping accuracy and efficiency. The methodology encompasses the devel opment of an ASV capable of wireless navigation and precise depth readings, detail ing the project flow, hardware and software integration, and iterative design processes. Field tests conducted in shallow water environments validated the system’s performance, with data analysis highlighting improvements in navigation accuracy and depth reading precision. These findings demonstrate the potential of ASVs in enhancing underwater mapping and supporting broader scientific, environmental, and navigational applications.
- PublicationDesign of UHF RFID fabric tag antenna(2024-07)Over the past few decades, there has been a growing demand for radio frequency identification (RFID) systems, which offer enhanced performance across various industrial applications and consumers such as object tracking and automatic identification. Despite these developments, the textile retail industry still uses barcodes for product tracking, a technique that relies on human scanning and results in less efficiency. Moreover, the limitations of barcode-based tracking, including vulnerability to theft, highlight the need for more effective alternatives. Implementing RFID technology in these systems enhances efficiency and performance. This project focuses on designing a fabric tag antenna compatible that works under Malaysia's UHF RFID system which is between 919 MHz and 923 MHz. The antenna uses woven conductive fabric for both the radiating patch and ground, with felt fabric as the substrate. The antenna is designed and analyzed using Computer Simulation Technology (CST) Microwave Studio. The prototype of the antenna is manually fabricated to validate its performance and findings. Measurement results show a return loss S11 of -19.17 dB at 921 MHz and a bandwidth of 17 MHz (913.5 - 930.5 MHz). The measured gain reaches 1.51 dB at the same frequency. Overall, the fabricated antenna shows good agreement between measurement and simulation results. Moreover, return loss and gain effects of fabricated antenna under wet and dry conditions were discussed.
- PublicationDesign of rope climbing robot(2024-07)In this ever-evolving field of robotics, innovative solutions are continually being developed to tackle dangerous and hazardous tasks. The climbing robot was developed to help humans reduce the risk of injuries in completing dangerous tasks such as inspections and maintenance in high-rise buildings, towers, cables, and steel bridges. By using a climbing robot, the task efficiency can increase and the cost of labour can be reduced. Some of the climbing robots have a maximum load that exceeds 50 kg, which makes the costs for development and maintenance significantly higher than another climbing robot with a lightweight load. Thus, to reduce the operational costs, the rope climbing robot was designed with a focus on lightweight structure and high efficiency in climbing the rope while functioning as a transportation carrier. For this purpose, the design of the rope climbing robot included a storage compartment that was able to hold multiple light objects, such as first aid kits, tools, and communications devices that were needed for emergency situations, maintenance tasks, and for clearer communication in areas with no signal coverage, such as mountain areas. Based on the results acquired from the experiments conducted, the rope climbing robot can climb the rope in horizontal position, moving forward and backward as well as upward and downward, with a rope at an angle of 15 degrees. By using these motions, the transportation process for carrying light objects is effectively achieved.
- PublicationDesign of ring oscillator with trimming circuit for performance tuning in CMOS 180nm technology(2024-07)Ring oscillator is an important component that used in many electronic circuits as it is able to generate clock frequency for the circuit. The output frequency that generated by the ring oscillator needs to be consistent when the ring oscillator undergo the process, voltage and temperature (PVT) variations. However, the performance of the ring oscillator is affected when undergo the process, voltage and temperature variations as the variations happen is sensitive to the ring oscillator. It will cause the frequency shifting happens in the output of the ring oscillator and degrades its clocking performance. Furthermore, the process variation will provoke uncertainty, voltage variations will cause the deviation in frequency from the ideal operating conditions and the temperature variations will cause the frequency instability. Hence, the trimming circuit is required to tune back the frequency when under PVT variations. A ring oscillator with trimming circuit for performance tuning is designed in this project. This project is constructed by using CMOS 180nm Technology and the Cadence Virtuoso Software is used to design and perform simulation for the designed circuit. An output frequency of 700MHz that obtained from ring oscillator is expected from the results of this project under Process, Variation and Temperature (PVT) variations. In the schematic design of overall circuit, there are 3 sets of capacitors are placed within the ring oscillator, each capacitor is connected to 1 nMOS switch, and each set of capacitors is connected to 1 voltage source. The capacitor and the nMOS switch in the same set have the same properties. Since there are total 3 voltage sources, Vtune1, Vtune2 and Vtune3 are used to control the ON of OFF of each set of capacitors, hence there are total of 8 arrangements of bits used for frequency correction. The simulations are then carried out for all the PVT cases. The arrangements of bits that selected for all cases in the pre- and post-layout simulation are different as the desired frequency is not obtained with the original arrangement of bits that selected in pre-layout simulation. The simulation results of frequency for all PVT cases in post-layout simulation are from 600MHz to 800MHz, all cases have an arrangement of bits able to obtain the desired frequency, 700MHz. The power consumption in pre-layout simulation is 33.1457µW, and in the post-layout simulation is 29.3857µW.
- PublicationDesign of a band gap reference voltage with trimming circuit for performance tuning in CMOS 180nm technology(2024-07)A bandgap voltage reference (BGR) circuit is used to provide a stable output for analog and digital blocks such as A/D and D/A converters. The output needs to be stable across several aspects, including temperature, power, and process variations. The BGR utilizes two quantities with opposite temperature coefficients (TC): PTAT (Proportional To Absolute Temperature) and CTAT (Complementary To Absolute Temperature). These quantities are added through multiplication with the correct weighting factors to achieve stability. However, process, voltage, and temperature (PVT) variations can affect the overall performance of the BGR. Process variation occurs due to the lithography step, while voltage variation is caused by fluctuations in the power supply. Temperature deviations can cause mismatches and functional failures. Hence, a trimming circuit is required to tune the performance of the BGR due to PVT variations. In this project, a bandgap reference voltage with a trimming circuit is designed. The overall circuit is constructed using 180nm CMOS technology. A stable BGR output of 1.2V is expected from this project. A two-stage operational amplifier with a gain higher than 60dB and a phase margin of 45° is required. The workflow of the project starts with identifying the properties of MOSFETs for ease of circuit calculation. Next, the calculation and design of the bandgap voltage reference and the two-stage operational amplifier are carried out. The trimming circuit is built to maintain the performance of the BGR. Simulations for both components are conducted to check the performance of the circuit. At the pre-layout simulation, the two-stage OPAMP achieves a DC gain of 75.2611dB and a phase margin of 77.633°. Across all corners of the pre-layout and post-layout simulations, the output reference voltage is 1.2V, with a temperature coefficient lower than 30ppm/°C.
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- ItemThe Relationship Between Perceived Authoritarian Parenting Style And Obsessive-Compulsive Personality Disorder Symptoms Among University Students : The Mediating Effect Of Type-D Personality And Resilience(Universiti Sains Malaysia, 2017-05)This study aims to investigate the occurrence of mediating effect of Type-D personality (TDP) and resilience on the effect of perceived authoritarian parenting style (PAPS) on obsessive-compulsive personality disorders (OCPD) among undergraduate students in a university in Penang, Malaysia. A survey was conducted among 122 undergraduate students in academic year 2016, where participants were asked to complete a set of questionnaire that consisted of Parental Authority Questionnaire (PAQ), Type–D Personality scale (DS14), Five-Factor Obsessive Compulsive Inventory (FFOCI), and Connor–Davidson Resilience Scale (CD-RISC-25). Quantitative approach was chosen because interrelationship among variables is the overarching aim of this study instead of the depth of the phenomenon. Tests of validity, reliability, and hypotheses were conducted by using PLS-SEM. Significant influence of PAPS have discovered on OCPD, TDP, and resilience. Mediation effect was indicated by TDP, while resilience did not show any mediation effect on the relationship between PAPS and OCPD. The results indicated that the existence of TDP among participants mediates the effect of their PAPS on their OCPD, while their resilience did not mediate the same effect. Implications of the results and recommendations for further research are discussed.
- ItemThe significance of borderline haemoglobin A₂ level among Kelantan population(Pusat Pengajian Sains Perubatan, Universiti Sains Malaysia, 2016)About 3-5% of Malaysians are thalassaemia carriers. Thalassaemia diagnosis based on haematological parameters is presumptive thus DNA analysis becomes necessary. Haemoglobin A2 (HbA2) level higher than 4.0% is a classic marker of β-thalassaemia carriers. However, when haematological parameters are suggestive of thalassaemia phenotype but not supported by HbA2 increment, this finding may put the diagnosis into dilemma. This cross sectional study was conducted to determine the proportion of borderline HbA2 level among samples taken for haemoglobin (Hb) analysis in HRPZ II from January 2015 until March 2016. HRPZ II received total of 11,790 samples for thalassaemia screening by CE from all over the state. Samples with HbA2 between 3.0% and 3.9% were selected and their haematological profiles (Hb, MCV, MCH, RBC, RDW and platelets) were analysed and then randomly selected for molecular testing (PCR) for β-gene mutation and α-gene deletion. MARMS-PCR was used for β-globin gene mutation detection while α-globin genes deletion detected by Multiplex Gap-PCR method. From 11,790 samples, 405 (3.4%) samples were found to have HbA2 between 3.0 and 3.9%. Out of that, 117 (28.9%) samples were selected by simple random sampling to proceed with PCR. From 117 samples, 45 (38.5%) showed positive molecular result in which 36 (30.8%) showed β-globin gene mutations, 8 (6.8%) showed α-globin gene deletions and 1 sample (0.9%) showed coexistence of α- and β-globin gene mutations. Out of these 37 samples with β-globin gene mutations, 32 (86.5%) had single gene defect while 5 (13.5%) had two gene mutations. The commonest of single β-gene mutation detected were Cd 19 (A-G) (45.9%), followed by IVS 1-1 (G-A) (24.3%), Poly A (13.5%) and CAP +1 (A-C) (2.7%). There was statistically significant association between HbA2 levels and positive molecular result. Interestingly, this study also showed 10 (27.0%) positive β-gene mutation even though the HbA2 level was normal at only 3.0%. There was significant number of people with borderline HbA2 and confirmed as thalassaemia carriers by PCR. This study revealed an important finding to consider revision of HbA2 range and haematological parameters that should prompt for DNA analysis in case of borderline HbA2 for the success of thalassaemia screening programme in our population.
- ItemDevelopment Of Semolina Film Reinforced With Zinc Oxide And Kaolin Nanoparticles(Universiti Sains Malaysia, 2017-12)This study was to examine the use of biopolymer-based biodegradable films as food packaging with the goal of reducing environmental pollution produced by synthetic food packaging. Plasticizer (30%, 40%, 50%), nano rod zinc oxide (1, 2, 3, 4 and 5%), nano-kaolin (1, 2, 3, 4 and 5%) and combination of nano-kaolin and ZnO-nr (1:4, 2:3, 3:2 and 4:1) were incorporated into a Semolina packaging to impact on the physico-chemical properties, microbiological features and organoleptic quality of ―Mozzarella cheese‖ throughout a storage period of 72 days. The effects of plasticizer and nanoparticles content on the water vapor permeability (WVP), oxygen permeability (OP), ultraviolet absorbance and transmittance, heat sealability, thermal, physical, morphology, mechanical and antimicrobial properties of the films were investigated.
- PublicationFactors Influencing Online Gambling Acceptance Among Thai Undergraduate Students(2023-02)This study aims to examine the factors that have impacts on Thai undergraduate students’ behaviour. Thus, the technological, psychological, and personal factors will be used to create a comprehensive model of TAM (Technology Acceptance Model) to explain why Thai undergraduate students tend to gamble online
- PublicationThe Mediating Effect Of Innovation Culture In Computerised Accounting Information System (Cais) Implementation Factors Towards Construction Companies Performance In Iraq(2023-07)The construction industry must implement new technologies, such as computerise accounting information systems (CAIS), to overcome a number of obstacles in order to adapt to the ever-changing construction environment. There is a need to investigate the effect of CAIS contexts on construction companies’ performance and the role of innovation culture as a mediator between CAIS and construction companies’ performance. A thorough evaluation of the literature was done in response to this identified research gap, focusing on the relationship between CAIS and construction companies’ performance. The finding of the literature study showed that CAIS and construction company performance are poorly understood. Empirical research is needed to close this gap and improve CAIS implementation industry practises. This study seeks to investigate the impact of CAIS contexts on the performance of construction companies and the role of innovation culture as a moderator in the relationship between CAIS and performance. The construction companies in Iraq were surveyed for this study using a structured, self-administered questionnaire. From a population of 208 businesses, a non-probability sampling technique was employed, resulting in a 73% response rate. The collected data were analysed to determine the influence of CAIS on the performance of construction companies. The results indicate that none of the three CAIS contexts had a substantial effect on the performance of construction companies.