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PublicationDesign and characterization of a 3.5 GHz CMOS power amplifier for low-band 5G applications(Taylor and Francis Ltd., 2025)A 3.5 GHz CMOS power amplifier (PA) designed for 5G applications is presented in this study, utilizing the 0.18 µm RF CMOS process technology. The circuit architecture comprises two stages: the first stage employs a cascode topology with a negative voltage applied to the transistor body technique to achieve sufficient gain and minimize current, thereby reducing power consumption. In the second stage, to ensure high efficiency, a class-E amplifier is being used. Measurement results indicate a power gain (S21) of 17.2 dB, a power-added efficiency (PAE) of 45.6% and a saturated power (Psat) of 8.5 dBm, obtained at 3.5 GHz. These findings validate the suitability of the proposed design at low-band frequency for 5G applications. The chip area for the proposed design is 2.45 mm². The discrepancy between simulation and measurement is due to the parasitic in the layout design.
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PublicationHigh-performance data throughput analysis in wireless ad hoc networks for smart vehicle interconnection(Multidisciplinary Digital Publishing Institute (MDPI), 2025)Vehicular Ad Hoc Networks play a crucial role in enabling Smart City applications by facilitating seamless communication between vehicles and infrastructure. This study evaluates the throughput performance of different routing protocols, specifically AODV, AODV:TOM, AODV:DEM, GPSR, GPSR:TOM, and GPSR:DEM, under various city and highway scenarios in complex networks. The analysis covers key parameters including traffic generation, packet sizes, mobility speeds, and pause times. Results indicate that TOM and DEM profiles significantly improve throughput compared to traditional AODV and GPSR protocols. GPSR:TOM achieves the highest throughput across most scenarios, making it a promising solution for high-performance data transmission in Smart Cities. For instance, GPSR:TOM achieves an average throughput of 3.2 Mbps in city scenarios compared to 2.8 Mbps for GPSR, while in highway scenarios, the throughput increases to 3.6 Mbps. Additionally, AODV:DEM records a throughput of 3.4 Mbps for high traffic generation, outperforming AODV:TOM at 3.1 Mbps and baseline AODV at 2.7 Mbps. The findings highlight the importance of optimizing data throughput to ensure reliability and efficiency in complex vehicle interconnection systems, which are critical for traffic management, accident prevention, and real-time communication in smart urban environments
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PublicationScanNote: a mobile application for enhanced text recognition and digital note-taking using machine learning-driven optical character recognition(Penerbit Akademia Baru, 2025)ScanNote, a novel note-taking application designed to address limitations in current text recognition tools. Traditional OCR systems often struggle with accurately recognizing handwritten text, rotated images or text in noisy environments, creating inefficiencies for users needing reliable digital conversion of physical documents. ScanNote integrates machine learning (ML) with OCR to enhance accuracy and adaptability, offering a solution that outperforms traditional methods. The development of ScanNote responds to the demand for a more effective tool that can seamlessly convert both printed and handwritten text into editable digital notes. Evaluation results show that for printed text, ScanNote achieves 96.3% accuracy, compared to 86.7% for traditional OCR. When text is rotated 180°, ScanNote maintains 89.7% accuracy, while traditional OCR drops to 55.3%. For handwritten text, ScanNote reaches 84.1% accuracy, outperforming traditional OCR’s 54.5%. In addition to superior text recognition, ScanNote includes core note-taking functions and export capabilities, positioning it as a competitive tool in the digital note-taking market. Future research will focus on further improving accuracy for complex texts and optimizing real-time processing. ScanNote represents a significant step forward in bridging physical and digital note-taking.
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PublicationQuantification of polyphenols content and antioxidant activity of Euphorbia Tirucalli l. extracted using Maceration and Soxhlet method(Semarak Ilmu Publishing, 2025)Euphorbia tirucalli L. (E. tirucalli) has gained attention for these past few years in terms of its phytochemical studies due to the antioxidant attribution of polyphenols source as its bioactive compounds in extracts. In order to extract important plant compounds, conventional extraction methods such as maceration and Soxhlet are still widely incorporated for plant extraction techniques due to their convenient application in laboratory settings. This study focused on the two conventional techniques; maceration and Soxhlet on polyphenols extraction of E. tirucalli using various extraction solvents. In order to provide insight into its potential for polyphenols extraction, yield percentage (%) and phytochemical tests such as Total Phenolic Content (TPC), Total Flavonoid Content (TFC), and antioxidant activity (%) were assessed. In terms of yield percentage, Soxhlet methanolic extract was found to be the best. The findings also suggest that both maceration and Soxhlet techniques are effective in extracting a significant amount of phenolics and flavonoid content in which highest value recorded were 17.26 ± 0.23 mgGAE/100g and 50.08 ± 1.13 mgQE/100g for maceration while 16.17 ± 0.21 mgGAE/100g and 43.02 ± 0.01 mgQE/100g for Soxhlet. Maceration with methanol solvent appears to be more effective for TPC and TFC while Soxhlet acetonic extract is chosen as the best for antioxidant activity with 75 .79 ± 0.04 % of radical scavenging activity in E. tirucalli extract. Thus, this study indicates the noteworthy potential of both maceration and Soxhlet techniques for polyphenols extraction.
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PublicationPerformance evaluation of mobility management protocols in inter-network wireless mesh networks: a comparative study(Penerbit Akademia Baru, 2025)This study addresses the critical challenge of mobility management in Wireless Mesh Networks (WMNs), focusing on the performance comparison of various Mobility Management Protocols (MMPs). The diverse range of MMPs, including Proxy Mobile IPv6 (PMIPv6), Fast PMIPv6 (FPMIPv6), Mobile IPv6 (MIPv6), Hierarchical MIPv6 (HMIPv6), Fast MIPv6 (FMIPv6), and Fast Hierarchical MIPv6 (FHMIPv6), present distinct advantages and limitations in terms of performance, scalability, security, and flexibility. Selecting the most suitable MMP for a given WMN application is a complex task, primarily due to the lack of comprehensive evaluation metrics that accurately reflect network efficiency. Furthermore, quantitative performance comparisons among these protocols are notably scarcen in existing research. Therefore, this research aims to contribute by categorizing MMPs applicable in Inter network WMN environments, developing a simulated WMN environment using the Network Simulator (NS-2), and conducting a thorough performance evaluation of various MMPs. Based on the result, the PMIPv6 outperform and able to provide 99.99% in packet delivery ratio, highest throughput compares to other MMPs. The outcomes of this study are expected to provide valuable insights for guiding the selection of MMPs based on specific application requirements, thereby contributing to the advancement of efficient and reliable WMN deployments