Fahisal Abdullah
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Preferred name
Fahisal Abdullah
Official Name
Fahisal, Abdullah
Alternative Name
Abdullah, Fahisal
Abdullah, F.
Main Affiliation
Scopus Author ID
47061221100
Researcher ID
CAK-3858-2022

Research Output
Now showing 1 - 2 of 2
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Publication

Analysis on silica and graphene nanomaterials obtained from rice straw for antimicrobial potential

2024-06 , Muhammad Nur Aiman Uda , N. H. A Jalil , Muhammad Firdaus Abdul Muttalib , Fahisal Abdullah , Uda Hashim , Subash Chandra Bose Gopinath , Shahidah Arina Shamsuddin , Nursakinah Abdul Karim , Ahmad Radi Wan Yaakub , Nur Hulwani Ibrahim , Tijjani Adam , Nor Azizah Parmin , Nadiya Akmal Baharum

This study focuses on the encapsulation of silica and graphene nanoparticles and their potential applications. The encapsulation enhances the properties and effectiveness of these nanoparticles, with silica providing stability and graphene contributing to high surface area and electrical conductivity. Characterization of silica-graphene nanoparticles was conducted using various techniques including High Power Microscope (HPM), Scanning Electron Microscope (SEM), Energy-dispersive X-ray spectroscopy (EDS), and 3D Nano Profiler. The antimicrobial activity of silica, graphene, and silica-graphene nanoparticles was evaluated using a disc diffusion assay against E. coli and B. subtilis at varying concentrations. Results showed significant antimicrobial activity, with the inhibition zone being directly proportional to the concentration. Silica-graphene nanoparticles demonstrated higher efficacy against E. coli compared to B. subtilis, attributed to differences in cell wall structure. Statistical analysis using ANOVA confirmed significant differences in antimicrobial activity among the tested components.

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Publication

Kinematic design and analysis of a 2RPS-1PRS parallel manipulator for hospital bed repositioning system

2023 , Fahisal Abdullah

Hospital Bed Repositioning System (HBRS) has become one of the most important studies to reduce physical injuries among caregivers during patient handling activities. However, hospital bed features, such as adjustable height, boosting, laterally repositioning and turning based on standalone mechanisms are generally ineffective since caregiver needs to frequently adjust the bed to get into the desired position. These frequent repetitions may increase the risk of physical injury of stress among caregiver. In terms of the structured design for the HBRS, the configuration of a parallel manipulator could be an effective approach to integrate these features into one hospital bed design. However, employing the parallel manipulator as a structured design with the ability to integrate specific features into a hospital bed can be a challenging issue due to the limitation of workspace. Hence, the objectives of this study were to develop a kinematics model and to analyse the performance of a parallel manipulator in the HBRS by considering the Trendelenburg, anti-Trendelenburg, repositioning, and height adjustable features. The design and development of the kinematics model based on the Denavit & Hartenberg method for the proposed parallel mechanism of 2RPS (revolute joint-prismatic joint-spherical joint)-1PRS (prismatic joint-revolute joint-spherical joint) was required to examine the functional requirements of the HBRS mechanism. Based on this kinematics model, workspaces and the singularity of the proposed 2RPS-1PRS parallel manipulator were analysed to determine the behaviour of the mechanism. Then, a numerical simulation that was designed using the MATLAB software and the prototype of the hardware mechanism were used to verify the performance of the proposed 2RPS-1PRS parallel manipulator. On specific geometry, the simulation and experimental results, considering the limitations of assembly errors and range of spherical angles, showed a similar trend within 5% error for active and passive joints. This finding highlighted the capability of the integrated features in the HBRS based on the mechanism of the 2RPS-1PRS parallel manipulator, which performed better than the standalone features. The integration of the HBRS features with the novelty of 2RPS-1PRS parallel manipulator offered a simple mechanism that could provide various motions, such as rolling, tilting, and shifting that represent the functional motions of existing hospital beds.

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