Nur Hafizah Ghazali
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Nur Hafizah Ghazali
Official Name
Nur Hafizah Ghazali, Ghazali
Alternative Name
Ghazali, Nur Hafizah
Ghazali, N. H.
Ghazali, N.
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Scopus Author ID
36104136600

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  • Publication
    Mobile Augmented Reality (AR) Marker-based for Indoor Library Navigation
    ( 2020-03-20)
    Rusnida Romli
    ;
    Razali A.F.
    ;
    Nur Hafizah Ghazali
    ;
    Nik Adilah Hanin Zahri
    ;
    Siti Zuraidah Ibrahim
    This paper presents the development of Augmented Reality (AR) for smart campus urbanization using library as the environment for the demonstration of the AR prototype. The main goal of the AR development is to help users to get information and direction easily using AR based mobile application when walking inside the library. In normal circumstances, users typically walk around and explore the library area before reaching their targeted destinations. Depending on the library size and number of reading corners, exploration and walking in the library can be time consuming. Therefore, an AR technology is introduced in this paper to improve the user experience inside the library in the right direction and information instantly. This application is developed using Vuforia software to set the image marker-based and process the output into Unity3D software, Android Studio for the Main Menu interface and IBM Watson for voice recognition. The final form of the application is successfully generated from the development of Augmented Reality (AR) application for the smart campus by using a library for the demonstration of the AR prototype. A series of application tests are conducted in each corner of the library to evaluate the effectiveness of developed AR.
  • Publication
    Characterization of all-optical Tofolli and Peres gates employing optimized SOA-NOLM
    ( 2020-01-08)
    Nur Hafizah Ghazali
    ;
    Mohamad Halim Abd. Wahid
    ;
    Nor Azura Malini Ahmad Hambali
    ;
    Nurjuliana Juhari
    ;
    Zahari S.M.
    ;
    Shahimin M.M.
    In this work, all-optical reversible gates namely Tofolli and Peres are studied and characterized. The gates utilize semiconductor optical amplifier (SOA) in nonlinear loop optical mirror (NOLM). The reversible gates are performed at data rate 10 Gb/s with narrow Gaussian pulses as input signals. Delay of 130 ps and injection current of 170 mA have displayed the optimum outputs in the SOA-NOLM. Extinction ratio is greatly reduced, thus less noise interferes the logic operation in this simple technique. It is observed that Peres gate has shown a higher output power compare to Toffoli gate. This could be due to multiple amplification that are experienced by the signals. Other than the gain, injection current and delay are shown to give major effect in producing the correct bits at the outputs. The SOA-NOLM also can be cascaded for other arithmetic signal processing operation at high frequency. It is also recorded that the design consumes low power especially in small signal gain process. Thus, the design indicates its versatility to be executed in photonic integrated circuits for ultrafast signal control through fiber networks.
  • Publication
    A new optimization strategy for wind/diesel/battery hybrid energy system
    ( 2022-01-15)
    Aziz A.S.
    ;
    Mohammad Faridun Naim Tajuddin
    ;
    Hussain M.K.
    ;
    Mohd Rafi Adzman
    ;
    Nur Hafizah Ghazali
    ;
    Ramli M.A.M.
    ;
    Khalil Zidane T.E.
    HOMER software is a powerful tool for modeling and optimization of hybrid energy system (HES). The main two default control strategies in HOMER are load following (LF) and cycle charging (CC) strategies. In these strategies, the decision to use the generator or battery at each time step is made based on the lowest-cost choice. Therefore, these strategies are difficult to be implemented in practice especially in countries with continuous fuel price fluctuations. In this study, a new dispatch strategy based on HOMER-MATLAB Link Controller for an isolated wind/diesel/battery HES is proposed to overcome the limitations of the default HOMER strategies. A detailed technical, economic, and greenhouse gas emission analysis is presented for the system under LF, CC, and the proposed dispatch strategies. Besides offering more realistic optimization, the results show that the proposed strategy offers the best economic and environmental performance with a net present cost of $56473 and annual CO2 emissions of 6838 kg. Furthermore, the sensitivity analysis reveals that the proposed strategy is not affected by the fuel price variation, in opposite to LF, and CC strategies which is affected dramatically by this variation. The findings are of paramount importance towards more realistic and efficient energy management strategies.
  • Publication
    An Effective Salp Swarm Based MPPT for Photovoltaic Systems under Dynamic and Partial Shading Conditions
    ( 2021-01-01)
    Jamaludin M.N.I.
    ;
    Mohammad Faridun Naim Tajuddin
    ;
    Ahmed J.
    ;
    Azralmukmin Azmi
    ;
    Syahrul Ashikin Azmi
    ;
    Nur Hafizah Ghazali
    ;
    Babu T.S.
    ;
    Alhelou H.H.
    This study proposes a duty cycle-based direct search method that capitalizes on a bioinspired optimization algorithm known as the salp swarm algorithm (SSA). The goal is to improve the tracking capability of the maximum power point (MPP) controller for optimum power extraction from a photovoltaic system under dynamic environmental conditions. The performance of the proposed SSA is tested under a transition between uniform irradiances and a transition between partial shading (PS) conditions with a focus on convergence speed, fast and accurate tracking, reduce high initial exploration oscillation, and low steady-state oscillation at MPP. Simulation results demonstrate the superiority of the proposed SSA algorithm in terms of tracking performance. The performance of the SSA method is better than the conventional (hill-climbing) and among other popular metaheuristic methods. Further validation of the SSA performance is conducted via experimental studies involving a DC-DC buck-boost converter driven by TMS320F28335 DSP on the Texas Instruments Experimenter Kit platform. Hardware results show that the proposed SSA method aligns with the simulation in terms of fast-tracking, convergence speed, and satisfactory accuracy under PS and dynamic conditions. The proposed SSA method tracks maximum power with high efficiency through its superficial structures and concepts, as well as its easy implementation. Moreover, the SSA maintains a steady-state oscillation at a minimum level to improve the overall energy yield. It thus compensates for the shortcomings of other existing methods.
  • Publication
    Design and analysis of small scale oyster mushroom cultivation
    ( 2024-02-08)
    Zahereel Ishwar Abdul Khalib
    ;
    Nur Hafizah Ghazali
    ;
    Mohamed Elshaikh Elobaid Said Ahmed
    ;
    Tai W.J.
    ;
    Letchumanan N.
    ;
    Azman N.F.F.
    ;
    Rodhi M.N.Q.
    Cultivators that grow oyster mushrooms keep failing due to a of lack control in temperature, humidity, soil moisture, and concentration of carbon dioxide. In order to grow great oyster mushrooms and avoid crop failure, the temperature must be between 22°C to 28°C and the relative humidity must be between 85% to 90%. The concentration of carbon dioxide (CO2) needs to be controlled below 800 during its growth phase. Failure to meet those parameters will result in the mushroom drying out, slowing growth, or stopping. As a result, oyster mushroom cultivators will require a system that can control the surrounding temperature and humidity, soil moisture, and concentration of CO2 conditions in order to produce good-quality oyster mushrooms. An automated environmental control system is constructed to handle the problem. In this system, by means of a feedback control loop system that monitors and activates the actuators when necessary, promising results of the oyster mushroom cultivation system are produced and analyzed.
      1
  • Publication
    Design of smart assist device for the visually impaired
    ( 2024-02-08)
    Zahereel Ishwar Abdul Khalib
    ;
    Nur Hafizah Ghazali
    ;
    Mohamed Elshaikh Elobaid Said Ahmed
    ;
    Salimin H.A.M.
    Vision impaired individuals suffer from the lack of surrounding information which makes moving around very hard for them. In this work, a smart belt is designed to assist the blind in detecting obstacles and holes in front of them. Upon detection, the smart belt will notify the user by means of a textual audio message. The device utilizes a Raspberry Pie single-board computer as well as two ultrasonic sensors as the main component. Test results indicate that the system manages to provide accurate measurement of the distance to the obstacles with +- 1cm error. The system has been designed to cater gait movement as well as the variability of flat surface. This is important to avoid false positive and false negative alarm to the user. Using the belt is very convenient as compared to the white stick. It is easy to wear on the waist and once activated the device shall auto-calibrate its distance to the ground before obstacle/hole detection mode is activated automatically a few seconds later.
      1