Wan Khairunizam Wan Ahmad
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Preferred name
Wan Khairunizam Wan Ahmad
Official Name
Wan Khairunizam, Wan Ahmad
Alternative Name
Wan, Khairunizam
Ahmad, Wan Khairunizam Wan
Khairunizam, W. A. N.
Main Affiliation
Scopus Author ID
57200576499
Researcher ID
E-6072-2011

Research Output

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  • Publication
    A 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.
    ;
    Shahriman Abu Bakar
    ;
    Zuradzman Mohamad Razlan
    ;
    Wan Khairunizam Wan Ahmad
    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.
  • Publication
    Tensile characterizations of oil palm empty fruit bunch (Opefb) fibres reinforced composites in various epoxy/fibre fractions
    ( 2022-10-15)
    Mohd Khairul Faizi Abd Rahman
    ;
    Shahriman Abu Bakar
    ;
    Mohd Shukry Abdul Majid
    ;
    Tamrin S.B.M.
    ;
    Israr H.A.
    ;
    Anas Abdul Rahman
    ;
    Guan N.Y.
    ;
    Zuradzman Mohamad Razlan
    ;
    Kamis N.A.
    ;
    Wan Khairunizam Wan Ahmad
    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.
  • Publication
    Improvement of Dissolved Oxygen in Perlis River based on Various Aeration Systems
    ( 2021-12-14)
    Muhammad Faiz Hilmi Rani
    ;
    Nur Saifullah Kamarrudin
    ;
    Shahriman Abu Bakar
    ;
    Zuradzman Mohamad Razlan
    ;
    Wan Khairunizam Wan Ahmad
    ;
    Mohd Sani Mohamad Hashim
    ;
    Ishak Ibrahim
    ;
    Anas Abdul Rahman
    ;
    Ibrahim Z.
    ;
    Mohd Khairul Faizi Abd Rahman
    ;
    Mohamad Aniq Syazwan Mohamed Hassan
    ;
    Abd Manap A.A.
    ;
    Zainuddin I.F.
    Water pollution is closely related to the Water Quality Index (WQI). One of the parameters in classifying WQI is dissolved oxygen (DO) that can be improved by introducing the surface and subsurface aerations. Herein, the Perlis River's water quality was investigated by evaluating the DO's improvement based on various aeration systems. The changes of DO (mg/L) and DO improvement (%) were evaluated during both low and high tide conditions. A total of 9 sets of data collection had been studied by comparing base DO (without running of aeration) and measured DO (with running of aeration) of river. The DO sensor was used to measure the changes of DO in the aeration measurement system. Results found that the DO improvement managed to achieve 74.89%, 10.18%, 35.58%, and 52.45% for water jet, air compressor, commercial venturi, and DIY venturi, respectively. Besides, different behaviour of DO's improvement was observed during low and high tide conditions.
      5  42
  • Publication
    Modelling on Impact of Building Obstruction for V2I Communication Link in Micro Cellular Environment
    ( 2021-03-01)
    Turner J.S.C.
    ;
    Shahriman Abu Bakar
    ;
    Azizi Harun
    ;
    Sohiful Anuar Zainol Murad
    ;
    Isa M.N.
    ;
    Ismail R.C.
    ;
    Ndzi D.L.
    ;
    Hashim M.S.M.
    ;
    Zuradzman Mohamad Razlan
    ;
    Wan Khairunizam Wan Ahmad
    ;
    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
  • Publication
    Development of Driving Simulation Experiment Protocol for the Study of Drivers’ Emotions by using EEG Signal
    ( 2024-06-01)
    Abdul Hafiz Abd Halin
    ;
    Wan Khairunizam Wan Ahmad
    ;
    Wan Azani Wan Mustafa
    ;
    Muhajir Ab. Rahim
    ;
    Zuradzman Mohamad Razlan
    ;
    Shahriman Abu Bakar
    ;
    Saidatul Ardeenawatie Awang
    The 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.
      1  32
  • Publication
    An Experimental Framework for Assessing Emotions of Stroke Patients using Electroencephalogram (EEG)
    ( 2020-06-17)
    Wan Khairunizam Wan Ahmad
    ;
    Yean C.W.
    ;
    Murugappan M.
    ;
    Ahmad Kadri Junoh
    ;
    Zuradzman Mohamad Razlan
    ;
    Wan Azani Wan Mustafa
    ;
    Shahriman Abu Bakar
    ;
    Ibrahim Z.
    ;
    Nurhafizah S.
    This research aims to assess the emotional experiences of stroke patients using Electroencephalogram (EEG) signals. Since emotion and health are interrelated, thus it is important to analyse the emotional states of stroke patients for neurofeedback treatment. Moreover, the conventional methods for emotional assessment in stroke patients are based on observational approaches where the results can be fraud easily. The observational-based approaches are conducted by filling up the international standard questionnaires or face to face interview for symptom recognition from psychological reactions of patients and do not involve experimental study. This paper introduces an experimental framework for assessing emotions of the stroke patient. The experimental protocol is designed to induce six emotional states of the stroke patient in the form of video-audio clips. In the experiments, EEG data are collected from 3 groups of subjects, namely the stroke patients with left brain damage (LBD), the stroke patients with right brain damage (RBD), and the normal control (NC). The EEG signals exhibit nonlinear properties, hence the non-linear methods such as the Higher Order Spectra (HOS) could give more information on EEG in the signal's analysis. Furthermore, the EEG classification works with a large amount of complex data, a simple mathematical concept is almost impossible to classify the EEG signal. From the investigation, the proposed experimental framework able to induce the emotions of stroke patient and could be acquired through EEG.
      1  17
  • Publication
    Derivation and validation of heat transfer model for Spark-Ignition engine cylinder head
    ( 2023-05-05)
    Hassan M.A.S.M.
    ;
    Zuradzman Mohamad Razlan
    ;
    Shahriman Abu Bakar
    ;
    Anas Abdul Rahman
    ;
    Mohd Afendi Rojan
    ;
    Wan Khairunizam Wan Ahmad
    ;
    Ibrahim Z.
    ;
    Ishak A.A.
    ;
    Mohd Ridzuan Mohd Jamir
    The valve train is located in the engine cylinder head, which has various operational heat transfer mechanisms to accommodate the combustion process. Most heat transfer studies in this area have only addressed medium-to high-power vehicles at a single running speed. In this study, a model of an air-cooled underbone motorcycle valve, valve seat, and engine cylinder head was tested to determine the thermal characteristics using actual engine operating conditions at low, medium, and high engine speeds. One-dimensional thermal simulation analyses were conducted to obtain the instantaneous heat-transfer coefficients of an actual engine. The average thermal value was determined as the boundary condition in the three-dimensional thermal analysis. A three-dimensional model was prepared using the ANSYS commercial computational fluid dynamics software package. The results show that as the engine speed increases, so does the thermal load toward the component in the engine cylinder head. The strongest temperature regions were concentrated around the combustion face. The exhaust valve held most of the heat, with the valve neck recording the highest temperature. For the intake valve, the combustion face registered the majority of the heat. The heat flux intensity was gathered in the contact surface area between the valve and its seat, between the valve stem and guide, and between the stem guide and tip section. A thermal survey was used to validate the three modelling results for two separate engine datasets. The cumulative relative errors for intake and exhaust valve seats for low engine speeds were 3.73% and 0.17%, respectively. The intake and exhaust valve seats had cumulative relative errors of 4.12% and 0.70%, respectively, at intermediate speeds. This methodology provides valuable information for analysing the heat characterisation of air-cooled engines. It can also be a useful blueprint for the automotive industry and other researchers involved in thermal measurements.
      32  2
  • Publication
    Engine Performance Analysis by Studying Heat Transfer in the Valve Seat through Steady-State Thermal Simulation
    ( 2021-12-14)
    Mohamad Aniq Syazwan Mohamed Hassan
    ;
    Shahriman Abu Bakar
    ;
    Zuradzman Mohamad Razlan
    ;
    Nur Saifullah Kamarrudin
    ;
    Wan Khairunizam Wan Ahmad
    ;
    Mohd Sani Mohamad Hashim
    ;
    Azizi Harun
    ;
    Ishak Ibrahim
    ;
    Azizul Aziz I.
    ;
    Zunaidi Ibrahim
    ;
    Mohd Khairul Faizi Abd Rahman
    ;
    Muhammad Faiz Hilmi Rani
    ;
    Anas Abdul Rahman
    ;
    Mohd Afendi Rojan
    ;
    Rishan Murali
    As the engine reached high speed, the exhaust valve temperature increased exponentially due to the exhaust gas produced by the combustion process between the mixture of air and fuel within the combustion chamber of the internal combustion engine. The valve is subjected to thermal loading due to high temperature and pressure within the cylinder, which must withstand a material temperature for sustainable and optimal operation. To avoid this loss, a perfect medium must be prepared to ensure that the heat is extracted smoothly. This can be done when the valve is in contact with the seat and there is a periodic heat transfer contact. Therefore, it is imperative to research the correlation between valve and valve seat to understand the two sections' heat transfer mechanism. In this study, thermal contact analysis was used to identify heat transfer between the valve and the valve seat as both parts are interconnected. This research also has an interest in studying the two surface conduction mechanisms as the exhaust valve closed in steady-state conditions. Thus, this study portrays a significant method, particularly for the determining the distribution of temperature, heat flux, and heat flux direction between the valve and its seat using ANSYS Workbench.
      2
  • Publication
    Integration of asset tracking system through trilateration method as detection mechanism
    ( 2019)
    M A Fadzilla
    ;
    Shahriman Abu Bakar
    ;
    Azizi Harun
    ;
    Mohd Sani Mohamad Hashim
    ;
    Zuradzman Mohamad Razlan
    ;
    Wan Khairunizam Wan Ahmad
    ;
    Z. Ibrahim
    ;
    Abu Hassan Abdullah
    ;
    J.S.C Turner
    ;
    K.A.A Kassim
    ;
    M.S.A Khalid
    ;
    Z. Jawi
    ;
    M.H.M Isa
    ;
    Rizalafande Che Ismail
    Demands for localization system has been growing rapidly in the last several years both for an outdoor and indoor area. In conjunction with this, the capability and reliability of this system to precisely locate and track objects of interest for the indoor area has catered researchers and study on how to do so. One of the major ideas on making it more advance is by incorporating the use of wireless devices into the system. There are numbers of issues that could interrupt the efficiency and success of the system. One of the main problems is the signal loss mainly caused by the attenuation of the signal as they propagate through from the transmitter to the receiver. These attenuations are mostly due to the surface types the signal are traveling on and the objects that are in the Line of Sight in between the transmitter and receiver. In order to ensure the most reliable and efficient wireless connection between transmitter and receiver, a propagation study on the signal is needed for us to analyze and find the best way to trade off the signal attenuation based on the environment surrounding the system. By doing so, a thorough system that has models that can work efficiently even if we are to consider the attenuation factors. The system consists of nodes installed inside the research institute that acts as both transmitter and receivers. The transmitter and receiver will then process the signal that will then determine their location. The receiver is connected to the laptop in order to get a real-time reading so that we will be able to locate the transmitter. A networked of nodes are installed inside the research institute for experiment and the layout of the research is conferred for future references. Data from the experiment are then analyzed and a model for the signal propagation alongside the research institute is created. This model will be able to apprehend the signal attenuation despite the surrounding environment such as furniture and walls. A completed asset tracking system with models of signal attenuation will be built in the future for a more efficient signal transmission.
      41  2
  • Publication
    CFD Simulation on Improving Water Quality based on Various Aerator Models to Demonstrate Cost Performance Analysis
    ( 2021-12-14)
    Nazrul Najmi Norbashah
    ;
    Muhammad Faiz Hilmi Rani
    ;
    Nur Saifullah Kamarrudin
    ;
    Shahriman Abu Bakar
    ;
    Zuradzman Mohamad Razlan
    ;
    Wan Khairunizam Wan Ahmad
    ;
    Mohd Sani Mohamad Hashim
    ;
    Ishak Ibrahim
    ;
    Anas Abdul Rahman
    ;
    Ibrahim Z.
    ;
    Mohd Khairul Faizi Abd Rahman
    ;
    Mohamad Aniq Syazwan Mohamed Hassan
    ;
    Abd Manap A.A.
    ;
    Zainuddin I.F.
    There are many types of aerator that can be used to perform a water treatment process either from air to water or from water to air approaches. Other than focusing on the performance itself, the usage cost of aerator should be forecasted in detail too to have a sustainable and economical method in remediating the polluted water. Therein, the cost performance analysis was demonstrated by performing a computational fluid dynamics (CFD) simulation on improving water quality based on various aerator models. The simulation was focused in a small-scale aeration tank that consists of a mixing chamber, air duct, and a few of bubble diffusers. The improvement of water quality was assessed by calculating the number of gas bubble particles produced by 4 different configurations of aerator model, namely aerator model A, B, C and D, respectively. Results found that the aerator model D (5 bubble diffuser at 620 L/min) produces the highest number of gas particles up to 72.2%. However, the aerator model C (5 bubble diffuser at 300 L/min) was found to achieve the most efficient and sustainable approach based on energy consuming and cost of aerator configuration when compared to the other aerator models.
      3  37