Leow Wai Zhe
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Preferred name
Leow Wai Zhe
Official Name
Wai Zhe, Leow
Alternative Name
Leow, Wai Zhe
Leow, W. Z.
Zhe, Leow Wai
Zhe, L. W.
Main Affiliation
Scopus Author ID
56178375200
Researcher ID
DXJ-9302-2022

Research Output

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  • Publication
    MPPT charge controller using fuzzy logic for battery integrated with solar photovoltaic system
    (Semarak Ilmu Publishing, 2025-05)
    Kumuthawathe Ananda-Rao
    ;
    Afifah Shuhada Rosmi
    ;
    Steven Taniselass
    ;
    Nor Hanisah Baharudin
    ;
    Leow Wai Zhe
    In comparison to other Renewable Energy (RE) resources, solar energy has become the most prominent and prospective source for generating electricity, substituting conventional sources. However, solar Photovoltaic (PV) energy production is dependent on solar irradiance and cell temperature. By implementing the Maximum Power Point Tracking (MPPT) algorithm, it is achievable to maximize the power from solar PV. In spite of this, there is still a slower convergence rate, a significant fluctuation around Maximum Power Point (MPP), and a drift issue caused by rapid irradiance variations in solar PV. In order to prevent oscillation and attain a steady state and continuous output of the PV module, a Fuzzy Logic (FL)-based MPPT has been designed in this work. With the buck converter as the DC-DC converter and the lead acid battery as the input, the Perturb & Observe (P&O) MPPT method is selected. The overall design will be developed using Matlab Simulink, and the efficiency of the FL-MPPT charge controller will be evaluated under constant and step irradiance. Additionally, the battery's State of Charge (SOC) will be monitored to prevent overcharging and discharge. In addition, the effectiveness of the controller will be evaluated with and without the MPPT method. On the basis of simulation results obtained from constant and step irradiance levels, the FL-MPPT charge controller with the P&O algorithm and the lead acid battery as the load was able to maintain maximum system efficiency while extending battery life. The FL-MPPT charge controller obtained about 96% efficiency for both irradiance profiles, whereas the system without the FL-MPPT algorithm only achieved 42% efficiency.
  • Publication
    Understanding Domain Knowledge in Initialization Method for K-Mean Clustering Algorithm in Medical Images
    ( 2022-01-01)
    Tan X.J.
    ;
    Nazahah Mustafa
    ;
    Mohd Yusoff Mashor
    ;
    Ab Rahman K.S.
    ;
    Wan Zuki Azman Wan Muhamad
    ;
    Leow Wai Zhe
    ;
    Cheor Wai Loon
    ;
    Oung Qi Wei
    This work serves as a preliminary study to investigate and identify the applicability of domain knowledge as an initialization method for K-Mean (KM), typically in medical images. For this purpose, 20 breast histopathology images were used as data set and the evaluations are focused on the clustering of the hyperchromatic nucleus. The iteration numbers and clustering results (i.e., accuracy, over-segmentation, and under-segmentation) are benchmarked with KM++ and the conventional random initialization method. The domain knowledge initialization method is found promising by achieving lower iteration numbers (<9), higher percentage in accuracy (85.5% (±2.27)), and lower percentages in over-segmentation (8.25% (±2.23)), and under-segmentation (7.00% (±2.14)). From this study, we hypothesize that the domain knowledge initialization method has the potential to be implemented as an initialization method and is posited to overperform some established initialization methods, typically for clustering tasks in medical images.
      1  37
  • Publication
    Analysis on the Effect of DC Current Changes on the Magnetic Field of Wireless Power Transfer
    ( 2023-01-01)
    Muhammad Irwanto Misrun
    ;
    Ali M.B.
    ;
    Nugraha Y.T.
    ;
    Baharuddin Ismail
    ;
    Nisja I.
    ;
    Leow Wai Zhe
    The generation of electromagnetic radiation in a solenoid, driven by alternating current (AC) voltage, is directly influenced by the voltage and current flowing through the solenoid. Exploiting this concept, wireless power transfer (WPT) systems can be developed. These systems consist of a sending coil and a receiving coil, both equipped with solenoids. The sending coil is connected to a half bridge circuit to generate AC voltage, which is then transmitted to the receiver coil. In this study, the effects of various factors on the performance of the wireless power transfer system were investigated, with a particular focus on the impact of DC voltage and input DC current. To examine these effects, an experimental setup was employed where the transmitter and receiver coils were powered by a DC voltage source. By varying the voltage and current parameters, the study aimed to analyze their influence on the wireless power transfer process. The simulation results show that 100 V and 150 V of DC current will produce 36.54 A and 54.8 A of input DC current respectively with constant resistor 7.54×10-2 Ω. The result shows that the input DC current is directly proportional with the magnetic field, AC current at sending and receiving coil, voltage at sending and receiving coil and AC power at receiving coil. Increasing the input DC current will increase the magnetic field, AC current at sending coil and receiver coil, voltage at transmitter coil and receiving coil and AC power at receiving coil and vice versa.
      1  27
  • Publication
    Breast cancer status, grading system, etiology, and challenges in Asia: an updated review
    (De Gruyter Brill, 2023)
    Tan Xiao Jian
    ;
    Cheor Wai Loon
    ;
    Cheng Ee Meng
    ;
    Khairul Shakir Ab Rahman
    ;
    Wan Zuki Azman Wan Muhamad
    ;
    Leow Wai Zhe
    The number of breast cancer incidences reported worldwide has increased tremendously over the years. Scoping down to Asia, in 2020, the reported incidences of breast cancer are appalling, comprising 1,026,171 cases, occupying up to 45.4% of cases across the globe. Breast cancer is a non-communicable disease, that emerges in variegated forms, self-subsistent, and the etiology is observed to be multifactorial, dependent on the individual reproductive pattern, hormonal factors, diet, physical activity, lifestyle, and exposure to certain advent procedures. Given this complexity, breast cancer is expected to undergo a persistent increment in the number of incidences in near future, exacerbating the public health quality, regardless of race, ethnicity, geographical subgroups, and socioeconomic. In this review article, the authors examine breast cancer in multiple facets, comprising the updated statistics on breast cancer, typically in Asia; etiology of breast cancer; diagnosis of breast cancer; grading system; and challenges in breast cancer from the country’s income perspective. Realizing the ever-increasing demand for quality treatment, here, the article also contemplates common therapies in breast cancer, such as breast-conserving therapy, mastectomy, postmastectomy radiation therapy, neoadjuvant chemotherapy, axillary surgery, chemotherapy, adjuvant medical therapies, biological and targeted therapies, and endocrine therapy. This review article intended to provide a brief yet broad panoramic view of breast cancer, to readers, ranging from newcomers, existing researchers, and relevant stakeholders in the topic of interest.
      1  2
  • Publication
    A Potential Controller for Smart Electrical Energy Management System
    ( 2021-06-11)
    Kumuthawathe Ananda-Rao
    ;
    Mohd Alif Ismail
    ;
    Afifah Shuhada Rosmi
    ;
    Leow Wai Zhe
    ;
    Surina Mat Suboh
    ;
    Muhammad Izuan Fahmi Romli
    ;
    Abdullah A.M.
    Integrated energy utilization has been recognized as a productive way towards better energy management, besides increasing Renewable Energy (RE) penetration. Thus, the combination of RE integrated with the Battery Energy Storage System (BESS) has been recognized as the primary solution where it is necessary to have a controller to interface the system efficiently. Hence, a smart electrical energy management system controller is designed and developed based on load leveling and peak shaving applications for real-time AC power management in this work. The main function of the controller is to continuously monitor and maintain the load demand and to produce a leveled or shaved load profile that will be seen at the grid network by controlling the battery operation. The testing results concluded that the controller able to perform both the energy applications. Overall, a dual function controller based on energy applications to maintain consumer load demand usage more securely and reliably, so that the utility bill is reduced and the battery lifetime is prolonged simultaneously is achieved in this work.
      9  31
  • Publication
    Fault detection and classification in three phase series compensated transmission line using ANN
    (IOP Publishing, 2020)
    Norfadilah Rosle
    ;
    Noor Fazliana Fadzail
    ;
    M I A Halim
    ;
    Mohamad Nur Khairul Hafizi Rohani
    ;
    Muhammad Izuan Fahmi Romli
    ;
    Leow Wai Zhe
    ;
    Nur Najihah Abu Bakar
    Series compensation consists of capacitors in series is used in the transmission lines as a tool to improve the performance after disturbed by a fault. Transmission line needs a protection scheme to protect the lines from faults due to natural disturbances, short circuit and open circuit faults. The fault can happen in any location of transmission line and it is important to know which location has been affected. So that, the fault can be eliminated and can maintain the optimum performance. Therefore, in this paper Artificial Neural Network (ANN) is used to detect and classified the fault happen in single line to ground fault and three phase to ground fault. Two different tests of each types of fault have been tested in order to prove the effectiveness of ANN to detect the fault location by using different length and fault resistance. The simulation has been accomplished in MATLAB with ANN fitting tool which build and train the network before evaluated its performance using regression analysis. The analysis shows that the ANN can accurately detect the different types of faults and classified it into the respective category even the random vectors are put on the system are used.
      10  1
  • Publication
    Development A Portable Solar Energy Measurement System
    ( 2021-07-26)
    Atika Z.
    ;
    Leow Wai Zhe
    ;
    Iszaidy I.
    ;
    Mohd Irwan Yusoff
    ;
    Safwati Ibrahim
    ;
    Muhammad Irwanto Misrun
    ;
    Wafi N.M.
    ;
    Saw S.X.
    This project presents the design and development a portable measurement device for measure and monitor solar panel parameters by using Internet of Things (IoT) concept. Solar energy measurement plays a very important role in the measurement of parameter reading for the determination of output generated, but the challenge is only performed manually at the work site using a clamp meter or a multimeter. Furthermore, it was very difficult to get the value at that time, and the data recovery error occurred. There are three specific objectives have been used for the project. Firstly, the relevant circuits for this project are design and built the circuit by using software. The output of the measurement solar irradiance, ambient temperature, solar panel temperature, current and voltage value were displayed on LCD. Next, IoT concept is used for solar panel measurement and monitoring. The value of the measurement and monitoring is used ThingSpeak cloud and ThingView application on the smartphone. It can be collected the portable solar for the energy measurement system can monitor on site, anywhere and anytime using IoT platform.
      37  1
  • Publication
    Improvement of the photovoltaic output performance using hybrid active and passive cooling system
    ( 2017)
    Leow Wai Zhe
    This thesis presents the improvement of the photovoltaic (PV) output performance using hybrid active and passive cooling system. The PV technology has been used for several years and has proven successful for power generation, but the challenge is to adapt to local environment conditions, mainly caused by changes in weather conditions. Furthermore, the output power of the PV panel decreases as the operating temperature of the PV panel increases. Therefore, the main purpose of this current research is to design various types of cooling system in order to improve output power of the PV panel. This study has four specific objectives. Firstly, the effects of weather conditions on the thermal behaviour of PV panels were studied using simulation and experimental methods. In the simulation study, the effect of weather conditions in the thermal behaviour of the PV panel was simulated using CATIA and ANSYS simulation software. This study was conducted based on the weather of Centre of Excellence for Renewable Energy (CERE), UniMAP, Malaysia. It was shown that as solar irradiance and ambient temperature increased, the operating temperature of the PV panel increased. As the wind speed increased, the operating temperature of the PV panel decreased. In the experimental study, the dust appearing on the surface of the PV panel resulted in a decrease in the performance of the PV panel. However, the presence of wind on the surface of the PV panel resulted in an increase in the performance of the PV panel. Secondly, the PV panels with various types of cooling system were designed and simulated using ANSYS simulation software in order to analyse their thermal behaviour under weather conditions of CERE, Perlis. This included direct current (DC) fan cooling system, DC water pump cooling system, paraffin wax cooling system, hybrid DC water pump and paraffin wax cooling system as well as hybrid DC water pump and DC fan cooling system. The results showed that the PV panel with hybrid DC water pump and DC fan cooling system has the lowest operating temperature of 35.43 °C compared to other PV panels.
      21  13
  • Publication
    Synchronized cell balancing charging of supercapacitors using PI control
    (IOP Publishing, 2020)
    M.A Rashed
    ;
    Muhammad Izuan Fahmi Romli
    ;
    M M Azizan
    ;
    C L Wai
    ;
    Leow Wai Zhe
    ;
    N F Rosle
    This paper covers the synchronized cell balancing charging of supercapacitors using pi control. The main objective of this project is to design a balanced circuit for supercapacitor and balance the voltage for each supercapacitor in series using pi control. This project aims to introduce a switch resistor design for a supercapacitor to balance the cell. Due to its low cost, easy to implement, and charge/discharge, the switch resistor design was chosen as the balanced circuit. The switch resistor design process was accomplished taking into account all the calculation for the design parameters. Using the pi control given to the circuit the stability and balancing in the voltage. The pi control design process was accomplished with the calculation for the design parameters.
      14  1
  • Publication
    Performance power evaluation of DC fan cooling system for PV panel by using ANSYS CFX
    ( 2017-09-26)
    Nur Syafiqah Zhubir
    ;
    Nasrul Amri Mohd Amin
    ;
    Mohd Irwan Yusoff
    ;
    Muhammad Irwanto Misrun
    ;
    Leow Wai Zhe
    ;
    Amelia A.R.
    A research has been conducted to find the optimum combination for DC fan air cooling system of photovoltaic (PV) panel. During normal operation of PV panel, it is estimated that only 15 % of solar radiation is converted into electrical energy. Meanwhile, the rest of the solar radiation is converted into heat energy which affects the performance of the PV panel. Therefore, the aim of this research is to investigate the performance power evaluation of DC fan cooling system for PV panel by using ANSYS CFX. The effect of airflow configuration of DC fan has been investigated. This is to analyze whether the airflow circulation of DC fan cause a change towards the maximum temperature of PV panel. Besides, the impact of varying number of DC fans attached at the back of PV panel is evaluated. The result of airflow circulation of DC fan has been discussed. Meanwhile, with the increment number of DC fans, the PV panel temperature drops significantly. As a conclusion, the optimum number of DC fans is two with the combination of inlet airflow.
      1  36