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Shahriman Abu Bakar
Preferred name
Shahriman Abu Bakar
Official Name
Shahriman, Abu Bakar
Alternative Name
Bakar, Shahriman A.B.
Shariman, A. B.
Ab, Shahriman
Abu Bakar, S.
Bakar, A. S.
Bakar, S. A.
Bakar, Shahriman Abu
Bakar, Sharifah Adzila Syed Abu
Bakar, S. Abu
Main Affiliation
Scopus Author ID
57196198202
Researcher ID
ELT-0087-2022
Now showing
1 - 10 of 38
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PublicationHeat transfer improvement in simulated small battery compartment using metal oxide (CuO)/deionized water nanofluid( 2020-02-01)
;Bin-Abdun N.A. ;Ibrahim Z.Improving the heat transfer coefficient of working fluids is essential for achieving the best performance of manufacturing systems. As a replacement of conventional working fluids, nanofluids have a high potential for improving this heat transfer coefficient. However, nanofluids are seldom implemented in actual systems, and several factors should be considered before actual application. Accordingly, this study investigated the thermophysical properties and heat transfer rate of CuO/deionized water nanofluid with and without sodium dodecyl sulfate (SDS) surfactants. Three different volumetric concentrations of the nanofluid were prepared using a two-step preparation method. The experimental steps were divided into two phases: static and dynamic. In these experiments, the thermophysical properties of the prepared nanofluids and the heat transfer coefficient were measured using an apparatus designed based on an actual heat exchanger for a lithium ion polymer battery compartment. The effects of flow rate and surfactants on the heat transfer rate of the nanofluids with varying volumetric concentrations of 0.08%, 0.16%, and 0.40% were analyzed. The results indicate that the heat transfer rate increases considerably as the flow rate increases from 0.5 L/min to 1.2 L/min and with the presence of surfactants. The highest heat transfer rate was obtained at a 0.40% volumetric concentration of CuO/deionized water nanofluid with SDS surfactant. -
PublicationA review of the application and effectiveness of heat storage system using phase change materials in the built environment( 2021-05-03)
;Ibrahim Z. ;Newby S. ;Hassani V. ;Ya'akub S.R.Global warming is the most significant threat that civilization faced within the 21st century. Buildings, which account for 40% of global consumption of energy and greenhouse gas emissions, play a key role in global warming. It is estimated that their destructive impact will grow by 1.8 percent per year by 2050, indicating that future energy consumption and emissions will be more critical than they are today. Therefore, the use of a latent heat storage system using phase change materials (PCM) is one of the effective ways of storing thermal energy and has the advantages of high-energy storage density and the isothermal nature of the storage process. PCM has been widely used in latent heat thermal storage systems for heat pumps, solar engineering, and spacecraft thermal control applications. Thermal energy conservation by latent heat is an ideal way to increase the thermal inertia of building envelopes, which would minimize temperature fluctuations, contributing to increased occupants' thermal comfort. For this reason, high-density PCM can be used effectively. This paper reviews recent studies of the application and effectiveness of using PCM in the built environment. -
PublicationTensile characterizations of oil palm empty fruit bunch (Opefb) fibres reinforced composites in various epoxy/fibre fractions( 2022-10-15)
;Tamrin S.B.M. ;Israr H.A. ;Guan N.Y. ;Kamis N.A.Oil palm empty fruit bunch (OPEFB) single fibers and reinforced composites were comprehensively characterized through tensile tests to assess their performance as potential reinforcing materials in polymer composites. The performances of OPEFB single fibers and reinforced composites with untreated and treated fibers conditions were compared. The fibers were variously treated with 3% sodium hydroxide, 2% silane, 3% sodium hydroxide mixed with 2% silane, and 3% sodium hydroxide prior to 2% silane for 2 hours soaking time. The highest toughness of the single fibers test was then selected to proceed with composites fabrication. The OPEFB composites were fabricated in 90:10, 80:20, 70:30, and 60:40 epoxy-fibre fractions. The result shows that the selected treated fiber composite exhibits better performance. The selected treated fiber composite increased the highest ultimate tensile strength by 145.3% for the 90:10 fraction. The highest Young’s Modulus was increased by about 166.7% for 70:30 fraction. Next, the highest toughness was increased by 389.5% for the 30:70 fraction. The treated fibers provided a better interlocking mechanism between the matrix and fibers in reinforced composites, thus improving their interfacial bonding. -
PublicationDevelopment of Driving Simulation Experiment Protocol for the Study of Drivers’ Emotions by using EEG Signal( 2024-06-01)
;Abdul Hafiz Abd HalinThe Brain-Computer Interface (BCI) is a field of research that studies the EEG signal in order to elevate our understanding of the human brain. The applications of BCI are not limited to the study of the brain wave but also include its applications. The studies of human emotions specific to the vehicle driver are limited and not vastly explored. The EEG signal is used in this study to classify the emotions of drivers. This research aims to study the emotion classifications (surprise, relax/neutral, focus, fear, and nervousness) while driving the simulated vehicle by analyse the EEG signals. The experiments were conducted in 2 conditions, autonomous and manual drive in the simulated environment. In autonomous driving, vehicle control is disabled. While in manual drive, the subjects are able to control the steering angle, acceleration, and brake pedal. During the experiments, the EEG data of the subjects is recorded and then analyzed. -
PublicationSimulation studies of the hybrid human-fuzzy controller for path tracking of an autonomous vehicle( 2021-01-01)
;Halin H. ;Haris H. ;Zunaidi I.Human intelligence and experience help them in making a decision and recognize a pattern. This ability enables the driver to take action even in an unexpected situation. The hybrid integration between human intelligence/experience and machine controller able to improve the autonomous vehicle path tracking capability. The path tracking capability is the main concern of the autonomous vehicle. The Fuzzy developed from the experiment’s data. The experiments (human navigation experiments) used to gather the appropriate data from humans while controlling the buggy car. Data then use to develop the membership functions for inputs and output of the Fuzzy controller. The simulation uses to study the performance of the Fuzzy controller. The recorded path tracking error from the simulations for the right and left turn maneuver is 9 m and 7.5 m, respectively. -
PublicationInvestigating the Effect of Individuality Factors in Measuring Aggression induced by Human Brain( 2022-01-01)
;Xutung K. ;Lugieswaran M. ;Mustafa W.A. ;Ali H.Mokhtar N.Aggression is a behaviour of human that may cause physical or emotional harm to others. Several factors that cause aggressive behaviour such as physical health, mental health and socioeconomic. Many previous researchers reported that aggression could be measured through either questionnaire or the brain signals. This paper proposes the experimental studies to collect the brain signal of the human subject for investigating the effect of individuality in aggression. Ten subjects are selected to perform the aggression activities. The experimental protocol for inducing aggression is proposed. In general, there are four tasks which is collecting brain data in relaxing state before and after the experiments, and data collection while playing game in muted and maximum volume levels. In the experiments, the subject are required to play a popular non-violence smart phone game named “Subway Surfers” and at the same time the EEG signals are recorded from the subject’s brain. In the signal pre-processing stage, a Butterworth filter is used to remove the noises contain in the signals. A windowing technique is employed for extracting significant features. A Pearson correlation technique is used to reduce and remain the less and most significant features. In the methodologies, the aggressiveness level A, is defined to investigate the effect of individuality in inducing the aggression signals. The proposed experimental protocol and signal processing techniques are seen able to generate level of aggression. -
PublicationDesign Optimization of Exhaust Manifold's Divergence Characteristics in Enhancing High-End Power in 115cc SI Engine( 2022-01-01)
;Murali R. ;Ishak A.A. ;Ika Syahira Abdullah ;Ibrahim Z.The exhaust system especially the exhaust manifold is an essential component that affects the performance of the Spark Ignition (SI) engine. The critical factor inside the exhaust system that affects the engine's performance is backpressure. Backpressure is known as the difference between maximum pressure in the exhaust system and atmospheric pressure. Based on previous studies, it was found that an un-optimal exhaust manifold's design leads to higher backpressure that reduces the performance and the fuel efficiency of the SI engine. This research aimed at enhancing the high-end power of the 115cc SI engine by optimizing the exhaust manifold's divergence characteristics through 1D engine analysis. S/N ratio analysis was used through Taguchi's method as a tool to conduct the design optimization. From the analysis, it was found that the optimal exhaust manifold's divergence configuration improved the mean brake power by 4.67% at high-end engine speed. It is expected that the optimal exhaust manifold's divergence configuration could also improve the engine's brake torque and fuel efficiency which could directly reduce the carbon footprint to the environment. -
PublicationEffects of variable arm length on uav control systems( 2020-01-01)
;Rizon M. ;Ang C.K. ;Solihin M.I.Zunaidi I.Quadrotor is a type of unmanned aerial vehicle that has been widely used in many applications, such as, policing, surveillance, aerial photography and agriculture. Conventionally, the control of quadrotor flight direction is accomplished by varying speeds of motors or manipulating torques. In this paper, a novel mechanism is proposed. The mechanism uses stepper motors to control the arm length for changing flight directions, while maintaining motors' speed at constant. A mathematical model has been created. The analysis results have shown that varying arm length can effectively control the moment of bending of quadrotors. Increasing the length of arms can result in the increase of the moment of bending without changing speed of motors, thus saving energies. Experimental results have shown that the new mechanism is able to carry more payloads which the motor speed can be utilized fully at 100% while the flight direction is been controlled by changing of the arm length compared to conventional flight control mechanisms. -
PublicationAn emotion assessment of stroke patients by using bispectrum features of EEG Signals( 2020)
;Choong Wen Yean ;Murugappan Murugappan ;Yuvaraj Rajamanickam ;Mohammad Iqbal Omar ;Bong Siao ZhengEmotion assessment in stroke patients gives meaningful information to physiotherapists to identify the appropriate method for treatment. This study was aimed to classify the emotions of stroke patients by applying bispectrum features in electroencephalogram (EEG) signals. EEG signals from three groups of subjects, namely stroke patients with left brain damage (LBD), right brain damage (RBD), and normal control (NC), were analyzed for six different emotional states. The estimated bispectrum mapped in the contour plots show the different appearance of nonlinearity in the EEG signals for different emotional states. Bispectrum features were extracted from the alpha (8–13) Hz, beta (13–30) Hz and gamma (30–49) Hz bands, respectively. The k-nearest neighbor (KNN) and probabilistic neural network (PNN) classifiers were used to classify the six emotions in LBD, RBD and NC. The bispectrum features showed statistical significance for all three groups. The beta frequency band was the best performing EEG frequency-sub band for emotion classification. The combination of alpha to gamma bands provides the highest classification accuracy in both KNN and PNN classifiers. Sadness emotion records the highest classification, which was 65.37% in LBD, 71.48% in RBD and 75.56% in NC groups. -
PublicationModelling on Impact of Building Obstruction for V2I Communication Link in Micro Cellular Environment( 2021-03-01)
;Turner J.S.C. ;Isa M.N. ;Ismail R.C. ;Ndzi D.L. ;Hashim M.S.M.Ramli M.F.In vehicular communication, signal transmission in vehicle-to-infrastructure (V2I) mode typically takes place on highways, urban, suburban and rural environments. The presence of buildings in these environments poses a challenge to model path loss (PL) due to multiple propagation mechanisms such as diffractions and reflections. However, very little attention has been made to address building effects on the performance of V2I communication links in microcell environment. This paper investigates signal propagation characteristics caused by the impact of building under micro-cellular environment whereby the base station or road-side-unit (RSU) is usually located under the rooftop of building to allow communication between RSU and mobile station or on-board-unit (OBU) on the road. The goal of this paper is to validate and discuss available path loss models based on effect of building obstruction towards RSU-OBU links specifically in residential housing area. The channel measurements are conducted based on static line-of-sight (LOS) settings of a real-world environment at 2.4 GHz frequency band using IEEE 802.15.4 XBee S2C compliant device to measure its receive power. The results are demonstrated based on received signal strength indicator (RSSI) and root mean square error (RMSE). The attenuation profile is validated and compared with suitable path loss models to evaluate best fit and most compatible model based on our measurements data and environment. The analysis shows that several V2I path loss models and V2V channel models are applicable to be used as a reference to model in LOS microcell environment with building obstruction. The finding shows that PL Urban yields the best fit V2I path loss model in terms of RMSE when compared to our measurement campaign at 2.4 GHz.2