Asyraf Hakimi Abu Bakar
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Preferred name
Asyraf Hakimi Abu Bakar
Official Name
Asyraf Hakimi, Abu Bakar
Alternative Name
Abu Bakar, Asyraf Hakimi
Abu Bakar, A. H.
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Scopus Author ID
57212349544
Researcher ID
HOH-0993-2023

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Development of Real Time Arsenic Heavy Metal Concentration Monitoring System

2021-11-25 , Asyraf Hakimi Abu Bakar , Hilmi W.N.W.Q.W. , Muhammad Nur Aiman Uda , Nor Azizah Parmin , Anas Mohd Noor , Zulkarnay Zakaria , Ahmad Nasrul Norali , Fook C.Y. , Rosly S.

This paper focuses on the ongoing development of real-time monitoring system with implementing the Internet of Things (IoT) element for arsenic heavy metal concentration in paddy field using pH sensor for data collection. The pH sensor will detect the hydrogen ion concentration from the prepared soil put in pot contained with various arsenic concentration. The developed system is then compared with the pH sensor in the market to verify its accuracy and sensitivity. The collected data will be transferred wirelessly into data cloud so that it can store the previous and current reading data. Besides, the system’s function is also to ensure the safeness of paddy plant to be planted with knowing the right amount of arsenic concentration can be passed.

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Lower extremity joint reaction forces and plantar fascia strain responses due to incline and decline walking

2021-01-01 , Noor Arifah Azwani Abdul Yamin , Khairul Salleh Basaruddin , Shahriman Abu Bakar , Ahmad Faizal Salleh , Mohd Hanafi Mat Som , Asyraf Hakimi Abu Bakar

Purpose: The present study aims to investigate the effect of incline and decline walking on ground and joint reaction forces (JRF) of lower extremity and plantar fascia strain (PFS) under certain surface inclination angles. Methods: Twenty-three male subjects walked on a customized platform with four different surface inclinations (i.e., 0°, 5°,7.5° and 10°) with inclined and declined directions. The motion of the ten reflective markers was captured using Qualysis motion capture system (Qualysis, Gothenburg, Sweden) and exported to a visual three-dimensional (3D) software (C-motion, Germantown, USA) in order to analyze the GRF, JRF and PFS. Results: The results found that the peak vertical GRF is almost consistent for 0° and 5° inclination slope but started to decrease at 7.5° onwards during decline walking. The most affected JRF was found on knee at medial-lateral direction even as low as 5°, to 10° inclination for both walking conditions. Furthermore, the findings also show that the JRF of lower extremity was more affected during declined walking compared to inclined walking based on the number of significant differences observed in each inclination angle. The PFS was found increased with the increase of surface inclination. Conclusions: The findings could provide a new insight on the relationship of joint reaction forces and strain parameter in response to the incline and decline walking. It would benefit in providing a better precaution that should be considered during hiking activity, especially in medial-lateral direction in order to prevent injury or fall risk.

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Home automation system for security and temperature control using microcontroller based with smartphone applications

2021-05-03 , Muhammad Aizat Abu Bakar , Fazreen Mohd Yusoff , Aminudin Anuar , Muhammad Nur Aiman Uda , Asyraf Hakimi Abu Bakar , Muhammad Nur Afnan Uda , Mohamed K. Sulaiman

In Malaysia, the El-Nino phenomenon happen in 2016 was caused the used of home appliances increasing including air-conditioner, fan and air cooler which are used frequently compared to other appliances. This report presents prototype development System for Security and Temperature Control using Microcontroller Based with Smartphone Application. The system has beneficial to reduce human labour besides energy saving and designed for special purposes which can easily maintain the temperature in sorrounding home. The system used several sensors for input parts including LM35 for temperature sensor and Passive Infra-Red (PIR) sensor for motion detector. For security system, the Radio-frequency Identification (RFID) has been used as security input user identification. A microcontroller arduino uno type is used as the system brain in the process part. In outputs part, servo motor has been used as door application while Light-Emitting Diode (LED) and buzzer as indicators when RFID is in use. A smartphone application is implemented in the system which allows the user to control a device remotely including home appliances through Bluetooth module. All data will display in Liquid Crystal Display (LCD) as user reference.

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Transient stability for IEEE 14 bus power system using power world simulator

2020-01-07 , Aminudin Anuar , Wahab M.A.A. , Syahrun Nizam Md Arshad @ Hashim , Muhammad Izuan Fahmi Romli , Asyraf Hakimi Abu Bakar , Muhammad Aizat Abu Bakar

Nowadays, demand for electricity is increasing every single day. This is due to the deep requirements in current economy. Generating electricity is an important element to ensuring a system operates in good condition and not being affected. At the same time, some problems have arisen as a phenomenon of transient stability. Hence, analysis needs to be done to control energy stability in rivalling current demand. Power system stability can be further divided into 3 sub-analysis starting with rotor angle stability which is the ability of synchronous machines of an interconnected power system to remain in synchronism after being subjected to a disturbance, voltage stability which is the ability of a power system to maintain steady voltages at all buses in the system after being subjected to a disturbance and also frequency stability which the ability of a power system to maintain steady frequency following a severe system disturbance resulting in a significant imbalance between generation and load. This analysis is used the IEEE Bus System 14 and analyzed using Power World Simulator (PWS) software. The variations in power angle, bus voltage and system frequency were studied with the help of three-phase balanced fault. Fast fault clearing times were analysed for a three-phase balanced fault in order to re-establish the stability of the system. Furthermore, impact of fault location on system was also computed to observe whether it affected the stability of the systems.

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Electromyography Signal Pattern Recognition for Movement of Shoulder

2021-11-25 , Ahmad Nasrul Norali , Anas Mohd Noor , Zulkarnay Zakaria , Muhammad Asymawi Mohd Reffin , Asyraf Hakimi Abu Bakar , Chong Yen Fook

Pectoralis major and deltoid are two muscles that are associated with the movement of the shoulder. Electromyography (EMG) signal acquired from these two muscles can be used to classify the movement of the shoulder based on pattern recognition. In this paper, an experiment for EMG data collection involves eight healthy male subjects who perform four shoulder movements which are flexion, extension, internal rotation and external rotation. Feature extraction of EMG data is done using root mean square (RMS), variance (VAR) and zero crossing (ZC). For pattern recognition, the classifiers that are used are Support Vector Machine (SVM), K-Nearest Neighbour (KNN), Linear Discriminant Analysis (LDA) and Quadratic Discriminant Analysis (QDA). Classification results shows highest accuracy on ZC feature using an SVM classifier with cubic kernel. The study on shoulder movement using EMG of pectoralis and deltoid muscles could be extended on arm amputees based on hypothesis that the EMG signal could be utilized for control of robotic prosthetic arm.

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Publication

Development of Real Time Arsenic Heavy Metal Concentration Monitoring System

2021-11-25 , Asyraf Hakimi Abu Bakar , Hilmi W.N.W.Q.W. , Muhammad Nur Aiman Uda , Nor Azizah Parmin , Anas Mohd Noor , Zulkarnay Zakaria , Ahmad Nasrul Norali , Chong Yen Fook , Rosly S.

This paper focuses on the ongoing development of real-time monitoring system with implementing the Internet of Things (IoT) element for arsenic heavy metal concentration in paddy field using pH sensor for data collection. The pH sensor will detect the hydrogen ion concentration from the prepared soil put in pot contained with various arsenic concentration. The developed system is then compared with the pH sensor in the market to verify its accuracy and sensitivity. The collected data will be transferred wirelessly into data cloud so that it can store the previous and current reading data. Besides, the system’s function is also to ensure the safeness of paddy plant to be planted with knowing the right amount of arsenic concentration can be passed.

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Publication

The effects of interactional justice and OCB on burnout: Empirical evidences among housemen in Malaysia public hospital

2021-05-03 , Sulaiman M.K. , Ummi Naiemah Saraih , Sakdan M.F. , Aminudin Anuar , Muhammad Aizat Abu Bakar , Muhammad Nur Aiman Uda , Asyraf Hakimi Abu Bakar

This study investigates the effect of interactional justice (IJ) and organizational citizenship behaviour (OCB) on burnout (BO) among housemen in Malaysia Public Hospital. This study involve 15 urban hospital in Malaysia. Quantitative method was used in the study to analyse the questionnaire. The questionnaire will distribute to the 800 housemen in 15 urban public hospital in Malaysia. The questionnaire will analyze by using PLS-SEM statistical tool. From the analyze the hypothesis are accepted and significant. The IJ and OCB can reduce the value of BO among housemen in public hospital. The information based on this study will be a valuable guide to the Ministry of Health (MoH) in and decrease the level of burnout among housemen in Malaysia. The hospital management also can use the information based on the study to upgrade the policy and standard operating procedure (SOP) towards the management of the housemen. Also, this study can be the basis to help the Malaysian housemen to identify the causes of burnout and improve their perspectives upon this issue. Not only that, knowing the dimensions of burnout and its causes can create a positive vibe in the medical environment, particularly among the ministry, hospital management, housemen, and patients.

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Classification of Electromyography Signal from Residual Limb of Hand Amputees

2022-01-01 , Ahmad Nasrul Norali , Anas Mohd Noor , Zulkarnay Zakaria , Al-Mahdi Y.S.M. , Fook Chong Yen , Asyraf Hakimi Abu Bakar

Several researchers had worked on collecting electromyography (EMG) signal from amputees and come out with dataset that could be utilized for study in EMG signal processing and classification for decoding of amputee movement intention. This paper presents the work on classification of EMG signal based on the residual limb of amputees with intuitive hand movement based on interactive exercises. Dataset is obtained from NINAPRO public database website where 11 amputee subjects performed intuitive exercise of 17 hand gestures and EMG signal is acquired from the residual arm. Eight feature extraction methods are performed to obtain the EMG feature which are Mean, Minimum, Median, Skewness, Kurtosis, Approximate Entropy, Fuzzy Entropy and Kolmogorov Complexity. Two classifiers are used for EMG classification which are k-Nearest Neighbour and Ensemble classifier. Results shows average accuracy of 87.65% with Ensemble classifier for classification of movement exercise with all features of EMG is used as input to classifier.

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