Azizi Harun
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Preferred name
Azizi Harun
Official Name
Azizi, Harun
Alternative Name
Harun, Azizi
Harun, A.
Bin Harun, Azizi
Main Affiliation
Scopus Author ID
15063856600
Researcher ID
V-6892-2019

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  • 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
    Modeling on impact of metal object obstruction in urban environment for internet of things application in vehicular communication
    ( 2020-01-08)
    Turner J.S.C.
    ;
    Azizi Harun
    ;
    Mohd Najib Mohd Yasin
    ;
    Norshamsuri Ali @ Hasim
    ;
    Shahriman Abu Bakar
    ;
    Fadzilla M.A.
    ;
    Sohiful Anuar Zainol Murad
    ;
    Nor Azura Malini Ahmad Hambali
    ;
    Razlan Z.M.
    ;
    Mohd Sani Mohamad Hashim
    ;
    Wan Khairunizam Wan Ahmad
    ;
    Phoon C.Y.
    Objects such as vehicles are considered one of challenging obstruction on the road and very little attention has been made to address its significance on the wireless signal. As such, this paper validates the impact of vehicle obstruction on signal propagation using received signal strength indicator (RSSI) based on the wireless channel measurements of realistic environmental obstruction at 2.4 GHz frequency band. Low mobility IEEE 802.15.4 XBee S2C compliant device which is designed to collect received signal power was used and these devices were deployed at area congested with cars. The channel measurements were conducted on LOS car parking area with two scenarios; single-sided and double-sided vehicle obstruction which mimics the obstruction of metal objects. The effect of existing vehicle on the signal propagation is demonstrated based on RSSI and RMSE. The attenuation profile of vehicular obstruction on wireless signal is modeled and compared with large-scale propagation models. Results show that metal object significantly reduce transmission range and signal power. The findings may incite for future implementation of cooperative deployment program and internet of things (IoT) applications in vehicle-to-infrastructure (V2I) and vehicle-to-vehicle (V2V) communication.
      1  31
  • Publication
    Signal propagation modelling for vehicle-to-infrastructure communication under the influence of metal obstruction
    ( 2021-12)
    Jamie Siregar Cynthia Turner
    ;
    Shahriman Abu Bakar
    ;
    Azizi Harun
    ;
    Mohd Sani Mohamad Hashim
    ;
    Zuradzman Mohamad Razlan
    ;
    D L Ndzi
    ;
    Rizalafande Che Ismail
    ;
    Sohiful Anuar Zainol Murad
    ;
    Mohd Nazrin Md Isa
    ;
    Shaiful Nizam Mohyar
    ;
    Mohammad Fadzli Ramli
    ;
    M K N Zulkifli
    Connected car has become one of emerging technology in the automotive industries today. This development preludes a rise in vehicular communication studies that primarily targets radio channel modelling on vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) communication mode. Considering vehicular obstruction, vast channel propagation studies have focused more on V2V mode while others consider the typical urban scenarios consisting of high traffic volumes of moving vehicles. Due to challenging propagation mechanisms and high complexity in such areas, radio propagation models applied in simulators assume an obstacle-free environment rather than considering the least effect imposed by metal obstruction on communication signal. Besides, there are limited studies pertaining to metal obstruction that considers several under-explored environments such as actual parking lots, junctions and other road infrastructure support. As such, this paper demonstrates signal attenuation analysis caused by the presence of metal objects in low density over obstacle-free environment on actual parking lot via V2I mode. Two scenarios such as LOS and NLOS conditions consisting of obstacle-free, cars and buses as static metal objects are evaluated. The aim of this research is to characterize signal strength caused by metal blockage on radio wave propagation predicated on the presence of vehicles as a subject of obstruction in comparison to obstacle-free vehicular environment. The validity of data is shown through received signal strength indicator (RSSI) and approximation analysis (RMSE) to demonstrate the efficiency of obtained measurements. The results demonstrated that Log-normal shadowing model yields the best fit to low-density metal obstruction scenario with smallest RMSE of 4.78 under bus obstruction whereas 5.72 under car obstruction.
      5  22
  • 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
    Determination of blind spot zone for motorcycles
    ( 2019-12-02)
    Mohd Sani Mohamad Hashim
    ;
    Hamati A.A.A.
    ;
    Mohd Hafzi M.I.
    ;
    Shahriman Abu Bakar
    ;
    Abdul Halim Ismail
    ;
    Muhamad Safwan Muhamad Azmi
    ;
    Azizi Harun
    ;
    Zuradzman Mohamad Razlan
    ;
    Nur Saifullah Kamarrudin
    ;
    Ishak Ibrahim
    ;
    Mohd Khairul Faizi Abd Rahman
    ;
    Mohd Asrul Md Saad
    ;
    Mohd Afendi Rojan
    The problem of the blind spot zone (BSZ) for motorcycles is common, as it causes many accidents that occur between motorcycles and cars, or motorcycles with other vehicles. The problem of BSZ is occurring for many reasons, such as if the motorcyclist wants to change the lane or manoeuvre or turn without realizing the presence of other vehicle which may cause a terrible collision and leads to casualties, either because of darkness, the full dependence on side mirrors that give a limited scope of vision, or due to a malfunction in the front lights of the car that prevented the motorcyclists from recognizing it. However there were limited research on identifation of BSZ for motorcycle, even though most vehicle accidents in Malaysia involved motorcycles. This paper discusses the initial works on the identification of BSZ for motorcyles. Three types of motorcycles were used to determine the BSZ using grid-based technique. From the data collected, the BSZ was identified for the motorcycles.
      2
  • Publication
    Investigating and improving Boeing aircraft composite panel industrial painting issues by designing smart robotic precision painting system
    ( 2021-10-25)
    Mohamad Aniq Syazwan Mohamed Hassan
    ;
    Shahriman Abu Bakar
    ;
    Zuradzman Mohamad Razlan
    ;
    Nur Saifullah Kamarrudin
    ;
    Mohd Sani Mohamad Hashim
    ;
    Wan Khairunizam Wan Ahmad
    ;
    Azizi Harun
    ;
    Ishak Ibrahim
    ;
    Mohd Khairul Faizi Abd Rahman
    ;
    Fadzilla M.A.
    ;
    Rahman M.F.A.
    ;
    Hamid N.M.F.N.A.
    ;
    Manaf A.A.
    ;
    Rani M.F.H.
    Aerospace Composites Malaysia (ACM) Sdn Bhd produces one of the aircraft components, which is an aircraft composite panel. Currently, the painting of the composite aircraft panel is manually conducted by the high skilled human operator. However, there are several issues of manual painting, which are the precision of the thickness specifications, uneven spray, dust-free, microbubble, colour appearance, and contour of the aircraft composite panel. Consequently, these issues contribute to the aircraft aerodynamic performances, productivity, and index time of the aircraft composite panel's production. Thus, the main objectives are to investigate the human painting mimicking robot incorporated with the existing painting environment. The proposed environment becomes smart precision painting systems. In conclusion, the proposed prototype will overcome the quality issue of aircraft composite panel painting faced by Boeing worldwide aircraft industries. Furthermore, the proposed prototype will increase productivity and contribute to the maintaining of the aircraft's aerodynamic performance.
      2  2
  • Publication
    Investigating the thermal characteristic of copper alloys valve seat towards engine performance enhancement of MODENAS CT115 through steady-state analysis
    ( 2021-10-25)
    Zainol M.A.A.
    ;
    Mohamad Aniq Syazwan Mohamed Hassan
    ;
    Shahriman Abu Bakar
    ;
    Zuradzman Mohamad Razlan
    ;
    Anas Abdul Rahman
    ;
    Mohd Sani Mohamad Hashim
    ;
    Nur Saifullah Kamarrudin
    ;
    Wan Khairunizam Wan Ahmad
    ;
    Azizi Harun
    ;
    Ishak Ibrahim
    ;
    Mohd Khairul Faizi Abd Rahman
    ;
    Muhammad Faiz Hilmi Rani
    MODENAS CT115 engine is a single overhead camshaft (SOHC) engine, with a rated power of 8.8 horsepower at 9000 rpm. One of the main concerns of engine research is the overheating of engines. Overheating can affects the performance of an engine by leading to a loss of strength and thermal strain. To prevent failure, thermal analysis is used to determine the flow of heat with precision to optimise temperature distribution. The investigation is done using ANSYS Thermal simulation on the CAD model of the engine cylinder head, intake and exhaust valve, and intake and exhaust valve seat insert. The comparison to the existing valve seat insert is made using three different valve seat insert materials: Beryllium-copper C17200, Bronze-copper C61300, and Brass C36000. The research results proved that Brass C36000 provides the best thermal reduction and heat transfer increment compared to the existing valve seat insert material.
      2  35
  • Publication
    Engine performance enhancement by improving heat transfer in between exhaust valve and valve seat through CFD (transient thermal) simulation
    ( 2021-05-03)
    Mohamad Aniq Syazwan Mohamed Hassan
    ;
    Shahriman Abu Bakar
    ;
    Zuradzman Mohamad Razlan
    ;
    Nur Saifullah Kamarrudin
    ;
    Aziz I.A.
    ;
    Wan Khairunizam Wan Ahmad
    ;
    Mohd Sani Mohamad Hashim
    ;
    Azizi Harun
    ;
    Ishak Ibrahim
    ;
    Ibrahim Z.
    ;
    Mohd Khairul Faizi Abd Rahman
    ;
    Muhammad Faiz Hilmi Rani
    ;
    Rishan Murali
    The combustion of the internal combustion engine results in high heat and pressure produce as exhaust gas. The high-temperature exhaust gas will transfer the heat to surrounding via convection, conduction, and radiation. In the combustion chamber, the exhaust valve and its seat will reach high temperatures due to hot gases exit through the engine exhaust port. This high temperature must be reduced to avoid damaging the engine. In this project, the existing material of the valve seat is tested using computational fluid dynamics simulation for heat analysis. Simulation of transient thermal is conducted to study the detailed behavior of heat transfer of the valve and valve seat in the engine. Four copper-based material of the valve seat is selected which is beryllium copper, chromium copper, brass, bronze are simulated. In the simulation, the brass valve seat has the highest heat absorbance rate which averagely 30% higher than cast iron valve seat in terms of temperature differences. Most of the copper-based valve seat can absorb averagely 10% to 30% more heat than cast iron valve seat depends on the material's thermal conductivity.
      4  30
  • Publication
    Effect of roadways plantation on signal propagation analysis in connected autonomous vehicle communication
    ( 2019)
    J S C Turner
    ;
    Shahriman Abu Bakar
    ;
    Azizi Harun
    ;
    Mohd Sani Mohamad Hashim
    ;
    Zuradzman Mohamad Razlan
    ;
    Wan Khairunizam Wan Ahmad
    ;
    Zunaidi Ibrahim
    ;
    Abu Hassan Abdullah
    ;
    M A Fadzilla
    ;
    K A A Kassim
    ;
    M S A Khalid
    ;
    Z Jawi
    ;
    M H M Isa
    ;
    S A Z Murad
    ;
    Rizalafande Che Ismail
    At present, the development of autonomous vehicle has altered the outlook of modern transportation worldwide. The state-of-the-art vehicular communication for transportation system is advancing, especially in vehicle to infrastructure (V2I) communication. An effective communication between vehicle and infrastructure has become a significant part of autonomous transportation criteria. The necessity for high quality of service communication inspire for good planning and preparation in communication process. Per se, this paper proposes vegetation attenuation models for advance planning of communication process between vehicle to infrastructure, defined mainly by plants, trees and vegetation along the roadways in Malaysia. The channel measurement performed in Universiti Malaysia Perlis test-bed having large tall trees and low shrubs along the routes resulted in several interesting results which would shape the planning of CAV communication. It is observed that communication close to low plantation or shrub requires high power consumption as the range is significantly reduced. It is also learned that certain types of plantations allows for different level of signal attenuation depending on the antenna heights. The research also found out that the attenuation profile follows strictly the log normal distribution and as such certain planning could be made to reshape the communication process to cater for this.
      2  39