Tidak Diketahui Pusat Pengajian - Tesis

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Multiband Cmos Power Amplifierwith Integrated High-Q Compact Inductor For Lora Application
(2023-05)
Arvind Singh Rawat
In the wide development of the Internet of Things (IoT), Machine-to-Machine (M2M), and biomedical applications in research and standardization, the spectrum of sub-GHz has received fresh attention. Long-range (LoRa) devices use the sub-GHz frequency bands to operate. The size of the chip becomes bigger when designed to target low frequencies and it is mainly contributed by the inductors. In this research, a high-performance CMOS power amplifier (PA) with a novel custom shape, high Qfactor compact inductor (HQCI) is fabricated in 130 nm, 6-metal layers CMOS process.
Development Of Lab On Printed Circuit Board Based Heavy Metal Detection
(2023-03)
Beh, Khi Khim
Heavy metal contamination in water sources is a significant environmental problem that poses a threat to public health. Electrochemical detection is a promising approach to detecting and quantifying heavy metals in water, due to the high sensitivity and selectivity it provides. However, traditional working electrodes, such as glassy carbon and mercury, are not ideal for detecting heavy metals due to limitations such as low sensitivity and toxicity. To address these limitations, this study aimed to improve the design and fabrication complexity of electro-analytical sensors by implementing a conventional Printed Circuit Board (PCB) fabrication technique. The fabricated sensor has achieved miniaturization of 40% compared to existing electrochemical sensors. According to cyclic voltammetry (CV) measurements, the fabricated sensor can produce a reversible peak reaction with different scan rates between 100 mV/s to 10 mV/s achieving a peak current ratio of 1. The modified Graphene Oxide (GO) of 0.2 mg/ml on the working electrode was explored as a sensing material due to its high sensitivity and selectivity in detecting heavy metals such as lead and cadmium, with an improvement of 45% in the detection of these metals. The optimum conditions for the detection of lead and cadmium were determined with a 10-minute accumulation time, -0.4 v reduction potential, 7-minute reduction time, and pH 4.0 of 0.1 M HCL buffer solution.
Piezoelectric Micro Ultrasonic Transducer (Pmut) With Fluidic Backing Layer As A Sensing Mechanism For Short Distance Underwater Microphone Application
(2022-02)
Ahmad, Khairul Azman
Piezoelectric micro ultrasonic transducer (PMUT) is vital for underwater microphone (hydrophone) applications. Hydrophone is generally used for listening or receiving any acoustic signal in underwater. Several studies have documented that PMUT served as underwater hydrophone with low receiving sensitivity and narrow operation bandwidth. The received acoustic signals with low receiving sensitivity are not accurate due to interference by unwanted signal. Acoustic transducers with narrow bandwidth were effected low resolution for underwater acoustic imaging. Narrow bandwidth transducers were captured for certain frequency only and it were difficult to catch acoustic signal at a long range frequency. In imaging, it is important the transducers can receive the signal for a long range of frequencies. The objectives of this study to increase the low receiving sensitivity transducer in the range of 300 kHz to 800 kHz and widen the narrow frequency bandwidth underwater ultrasonic transducer. Subsequently objectives are a PMUT designed using d33 mode piezoelectric structure, flexural membrane and fluidic backing layer.
Performance Of Urban Stormwater Drainage System Through Dry Detention Pond (Case Study: Kota Damansara, Selangor)
(Universiti Sains Malaysia, 2009-07)
Liew, Yuk San
Due to the rapid development, flooding occurred progressively. This scenario is worsened if improper drainage systems were implemented. The inattentiveness to all the problems occurred will generate the possibility for more severe flooding risk and creates further damages of property and loss of lives. Since the implementation of Urban Stormwater Management Manual of Malaysia (MSMA) in 2001 by Department of Irrigation and Drainage, Malaysia, the Best Management Practices (BMPs) through construction of detention ponds have been encouraged. After 8 years of implementation, there is a need to reconsider the recommendation of constructing detention pond for water quantity control by evaluating performance of the constructed dry detention ponds using computer modelling.
Extraction And Physico-Chemical Characterization Of Antioxidative Pectic-Polysaccharide From Pinto Bean (Phaseolus Vulgaris ) Pods
(Universiti Sains Malaysia, 2014-07)
Kamarudin, Fazlina
This thesis describes the extraction and characterization of pectic-polysaccharide from the pods of pinto bean. Different pH (pH 2, pH 4 and pH 6), temperature (50, 60 and 70 °C) and time (1, 3 and 5 h) were implemented in the extraction and their effects on the antioxidative and physico-chemical properties were evaluated. The maximum pectic-polysaccharide yield of 38.5 g/100 g was extracted at pH 2, for 3 h at 70 °C. The highest Total Phenolic Content was 285.5 mg GAE/100g (pH 4, T: 50 °C, t: 1 h) while the highest Diphenyl-1-picrylhydrazyl radical scavenging activity and Ferric Reducing Antioxidant Power activity was 10.7 %DPPHsc (pH 6, T: 70 °C, t: 3 h) and 4.03 mM FeSO4/g (pH 4, T: 70°C, t: 1 h), respectively. Total polysaccharide content (476.2 mg maltose/g, pH 4, T: 70 °C, t: 3 h), uronic acid content (456.7 mg Gal/g, pH 2, T: 60 °C, t: 5 h), degree of esterification (59.9 %, pH 2, T: 70 °C t: 3 h), water holding capacity (51.1 g of water held/g, pH 6, T: 70 °C, t: 3 h), oil holding capacity (33.4 g of oil held/g, pH 6, T: 50 °C, t: 5 h), emulsifying activity (43.8 %, pH 2, T: 60 °C, t: 5 h) and emulsion stability (40.5 %, pH 2, T: 60 °C, t: 3 h) were reported. Moreover, FTIR spectra showed the presence of major chemical groups of pectin at region between 1000 and 2000 cm-1 and indicated that the extracted pectic-polysaccharide is of pectin. Rheological properties of the pectic-polysaccharide were also studied. The shear thinning behaviour and viscosity of the extracts were observed. Pectic-polysaccharide extracted at pH 2, 70 °C for 5 h produces gels with highest viscosity under pH 4.5 and pH 6.5. Results suggest that pectic-polysaccharide from the pods of pinto bean has the potential to be exploited as a source of commercial pectin.

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