Zulkarnay Zakaria
Thumbnail Image
Preferred name
Zulkarnay Zakaria
Official Name
Zulkarnay, Zakaria
Alternative Name
Zakaria, Z. N.
Zakaria, Zulkarnay
Zakaria, Z.
Main Affiliation
Scopus Author ID
24403085300
Researcher ID
F-5218-2010

Research Output

Filters

29
Reset filters

Settings
Now showing 1 - 10 of 29
  • Publication
    Development of five port reflectometer for reflection based sensing system
    ( 2017-03-13)
    Setno Baharuddin
    ;
    Cheng Ee Meng
    ;
    Lee Kim Yee
    ;
    Siti Khadijah Za'aba
    ;
    Nurul Syahirah Khalid
    ;
    Zulkifly Abbas
    ;
    Nashrul Fazli Mohd Nasir
    ;
    Mohd Afendi Rojan
    ;
    Zulkarnay Zakaria
    Five-Port Reflectometer is a microwave passivedevice where it implements the six-port algorithm to measure the complex reflection coefficient of material under test (MUT) through reflection on interface between MUT and microwave sensor. Initially, the Six-Port Reflectometer (SPR) was introduced by Engen in 1977 and major component used insix-port technique was designed in many types. When Riblet and Hanssonproposed ring junction with 5 ports only on 1981. Six ports ring junction has been reduced to five ports. In this paper, a dual frequency five ports ring junction circuit was designed, simulated and fabricated for reflection based sensing system. The fabricated five port ring junction is operating at frequencies of 0.64 GHz and 2.42 GHz. The measured result had good agreement with the simulated results for dual frequencies in terms of magnitude and phase.
  • Publication
    Dielectric spectroscopy technique for carbohydrate characterization of fragrant rice, brown rice and white rice
    ( 2017-11-20)
    Cheng Ee Meng
    ;
    Kok Yeow You
    ;
    Lee KimYee
    ;
    Abbas Z.
    ;
    Hasliza A Rahim @ Samsuddin
    ;
    Khor Shing Fhan
    ;
    Zulkarnay Zakaria
    ;
    Lee Y.S.
    This study was conducted to investigate the feasibility of microwave dielectric spectroscopic technique in characterizing commercial rice due to different level of moisture content. There are some unethical rice industry runner mixes good qualities of rice which can be sold at high price with low cost and quality of rice to maximize profit. It causes fraudulency in business and great lost in term of money to nation who take rice as staple food. It happens frequently in Asian country which is active in agricultural activities. This technique is implemented using Keysight E8362B network analyzer in conjunction with an Keysight 85070E dielectric probe ranging from 200 MHz to 10 GHz. The samples of study are commercially available at market, namely fragrant rice, white rice, and brown rice, respectively. These are the popular and favorite rice for Malaysian due its delicacy and affordable price. Nutrient level for fragrant rice, white rice, and brown rice in terms of protein, moisture, carbohydrate and fat are different and unique. It leads to various electromagnetic responses toward frequency. Dielectric and reflection measurement were conducted to characterize these rice. The presence of polar and non-polar molecules in nutrient of rice causes variation of dielectric and reflection behavior over the operating frequency range.
  • Publication
    Electromyography Signal Pattern Recognition for Movement of Shoulder
    ( 2021-11-25)
    Ahmad Nasrul Norali
    ;
    Anas Mohd Noor
    ;
    Zulkarnay Zakaria
    ;
    Muhammad Asymawi Mohd Reffin
    ;
    Asyraf Hakimi Abu Bakar
    ;
    Chong Yen Fook
    Pectoralis major and deltoid are two muscles that are associated with the movement of the shoulder. Electromyography (EMG) signal acquired from these two muscles can be used to classify the movement of the shoulder based on pattern recognition. In this paper, an experiment for EMG data collection involves eight healthy male subjects who perform four shoulder movements which are flexion, extension, internal rotation and external rotation. Feature extraction of EMG data is done using root mean square (RMS), variance (VAR) and zero crossing (ZC). For pattern recognition, the classifiers that are used are Support Vector Machine (SVM), K-Nearest Neighbour (KNN), Linear Discriminant Analysis (LDA) and Quadratic Discriminant Analysis (QDA). Classification results shows highest accuracy on ZC feature using an SVM classifier with cubic kernel. The study on shoulder movement using EMG of pectoralis and deltoid muscles could be extended on arm amputees based on hypothesis that the EMG signal could be utilized for control of robotic prosthetic arm.
      1
  • Publication
    Classification of White Blood Cells Based on Surf Feature
    ( 2021-01-01)
    Anas Mohd Noor
    ;
    Zulkarnay Zakaria
    ;
    Aishah Mohd Noor
    ;
    Ahmad Nasrul Norali
    Conventional blood analysis using blood smear image were performed manually by experts in hematology is tedious and highly depending on the level of experience. Currently, computer-assist technology is developed to reduce the time-consuming process and improved accuracy. As an example, various image processing techniques used to quantify such as white blood cells (WBCs) morphological conditions or classification in the blood smear image, which assist experts in developing confidence decision making in the analysis of cells conditions linked to the specific diseases. However, the WBCs shape features are arbitrary than the red blood cells (RBCs) because of the maturation state, cell orientations or positions, cell color variations, and the quality of the image captured influences the performance of classification accuracy. Therefore, we proposed a scale and rotation invariance feature for WBCs classification using speed up robust feature (SURF). SURF is suitable to be applied in identifying objects even though the orientation, scale, and position are varying, such as WBCs in microscopic blood smear images. We analyzed the classification performances using a support vector machine (SVM) and an artificial neural network (ANN) of WBCs types in the microscopic image based on the cell nucleus. The results show that the purposed SURF feature method has an excellent performance of accuracy for both methods and suitable to be utilized for the application of cell types classification.
      1
  • Publication
    Design and evaluation of Magnetic Induction Spectroscopy probe for pH measurement in fetal hypoxia using COMSOL Multiphysics Simulation
    ( 2022-01-01)
    Siti Fatimah Abdul Halim
    ;
    Zakaria M.H.
    ;
    Zulkarnay Zakaria
    ;
    Aiman Abdulrahman Ahmed
    ;
    Ahmad Nasrul Norali
    ;
    Anas Mohd Noor
    ;
    Jaysuman Bin Pusppanathan
    ;
    Mohd Hafiz Fazalul Rahiman
    ;
    Siti Zarina Mohd Muji
    ;
    Ruzairi Abdul Rahim
    Fetal Blood Sampling (FBS) is the term used to describe the current method of monitoring the foetal condition within the mother’s womb. FBS required the medical officer to make a small incision on the foetus’s head in order to collect blood for analysis of the blood pH level in order to prevent acidosis or foetal hypoxia. The FBS method, on the other hand, is invasive and increases the risk of infection for both mother and child. Magnetic Induction Spectroscopy (MIS) is a novel method for diagnosing the foetus’s pH level that is non-invasive and non-intrusive. A single channel MIS system is composed of a transmitter (TX), a receiver (RX), and an electrical circuit that generates and receives magnetic fields in response to the conductivity of the sample (blood) due to the presence of weak electrolytes (H+ and OH-). The purpose of this research is to develop and evaluate five different designs of TX-RX coils. The coils are designed using the Planar Zero Flow Coil (PZFC) concept, which allows for multiple coil configurations and input-output configurations. The results show that Design 2 open set model was the optimal coil design for MIS system probe, as well as some contributions to the pH evaluation process.
      7  5
  • Publication
    Study of eddy current density distribution in a contactless breast cancer detection mechanism using magnetic induction spectroscopy
    ( 2017-01-01)
    Gowry Balasena
    ;
    Shahriman Abu Bakar
    ;
    Zulkarnay Zakaria
    ;
    Ryojun Ikeura
    ;
    Zuradzman Mohamad Razlan
    ;
    Hazry Desa
    ;
    Wan Khairunizam Wan Ahmad
    ;
    Cheng Ee Meng
    ;
    Mohd Afendi Rojan
    Breast cancer is a throbbing disease that no longer needs an introduction. This is especially true among women due to their unique breast structure that naturally has more breast tissues compared to that of man’s. It is been forecasted that in 2015, a minimum of 60290 new cases of breast cancer will be reported. The goal of this study is to analytically evaluate the changes in the induced Eddy current densities as a function of di-electrical properties of the breast tissue with respect to tumor positioning as well as its size. This is achieved by running numerical simulations on the proposed mechanism of magnetic induction to detect tumors among healthy breast tissue via a 2D breast model configuration. The analytical results presented in this article, proved that the multi frequency magnetic induction principle is viable in detecting the breast lesions as small as 0.2 cm non-invasively through the distributions of the induced Eddy current density. While important pattern of the induced current were reflected when the tumors are located at the far ends of the breast diameter. The minimum results computational time with the proposed system is 10 s.
  • Publication
    Optimization on fermentation of seaweed (Gracilaria sp.) as feedstock for bioethanol production by Saccharomyces cerevisiae
    ( 2020-12-18)
    Zakaria N.Z.I.
    ;
    Zhen A.W.
    ;
    Mohd Hassan S.A.
    ;
    Zulkarnay Zakaria
    In this study, dried seaweed (Gracilaria sp.), a red algae was used as feedstock for the production of bioethanol due to its high carbohydrate content (76.67 %). Dried seaweed is hydrolysed into reducing sugar by using dilute acid hydrolysis pre-treatment at optimized conditions (0.1 M sulphuric acid (H2SO4), 121 C, 30 minutes) and able to obtain 18.438 g/L of reducing sugar. This hydrolysate is converted into bioethanol by Saccharomyces cerevisiae via fermentation. Two significant factors, namely, fermentation temperature and medium pH were screened by performing One-Factor-At-A-Time (OFAT) analysis. The first factor manipulated was the fermentation temperature (40-50 C at pH 4.5), followed by medium pH (pH 4.0-5.0 at 45 C). Ethanol with concentration of 3.4202 g/L was successfully obtained from OFAT analysis under condition of 45 C and pH 4.5. The significant factors were then statistically optimized using Central Composite Design (CCD) in Response Surface Methodology (RSM). From the data analyzed from Design of Experiment (DoE), at its optimum fermentation conditions (44.83 C and pH 4.48), the maximal ethanol production obtained is 3.8395 g/L. A validation test with triplicate was performed to validate the actual with predicted value and result in 1.49% deviation is accepted.
  • Publication
    Classifying white blood cells from a peripheral blood smear image using a histogram of oriented gradient feature of nuclei shapes
    ( 2020-06-11)
    Anas Mohd Noor
    ;
    Haniza Yazid
    ;
    Zulkarnay Zakaria
    ;
    Aishah Mohd Noor
    Researchers developed various methods and algorithms to classify white blood cells (WBCs) from blood smear images to assist hematologists and to develop an automatic system. Furthermore, the pathological and hematological conditions of WBCs are related to diseases that can be analyzed accurately in a short time. In this work, we proposed a simple technique for WBC classification from a peripheral blood smear image based on the types of cell nuclei. The developed algorithms utilized a histogram of oriented gradient (HOG) feature typically known for application in human disease detection. The segmentation of WBC nuclei utilizes a YCbCr color space and K-means clustering techniques. The HOG feature contains information about the cell nuclei shapes, which then is classified using a support vector machine (SVM) and backpropagation artificial neural network (ANN). The results show that the proposed HOG feature is useful for WBC classification based on the shapes of nuclei. We are able to categorize the type of a WBC based on its nucleus shape with more than 95% accuracy.
  • Publication
    Inhibition of Aspergillus flavus by Momordica charantia Ethanolic Leaves Extract for Mushroom Protection
    ( 2023-06-09)
    Noor Hasyierah Mohd Salleh
    ;
    Zulkarnay Zakaria
    ;
    Aziz N.H.
    ;
    Ahmad Anas Nagoor Gunny
    ;
    Alina Rahayu Mohamed
    ;
    Munusamy T.
    Pleurotus ostreatus, better known as oyster mushroom is one of the world’s widely cultivated mushroom. Infection from pathogenic fungi is one of the major reasons causing losses of mushroom during cultivation. The objective of this study is to investigate the antifungal property of Momordica charantia leaves extract against Aspergillus flavus for mushroom protection. The inhibitory effect of M. charantia leaves extract against A. flavus isolated from infected P. ostreatus mushroom bag was investigated using pour plate technique. Inhibition of A. flavus mycelial growth was the highest at extract concentration of 9.64 v/v %, temperature 26℃ and incubation time of 96 hours with inhibitory value of 70.58 ± 0.00 %, 78.4 ± 0.00 % and 63.33 ± 2.89 % respectively. Structural morphology of the mycelia grown on the treated plate also showed morphological alteration compared to the control plate. Hence, Momordica charantia leaves extract may serves as a promising fungicides alternative to chemical use for controlling invasion of A. flavus on oyster mushroom.
  • Publication
    Feasibility analysis of microwave frequency to detect wood for potential microwave application
    ( 2017-03-13)
    Thomas W.K.T.
    ;
    Mohd Hafiz Fazalul Rahiman
    ;
    Soh Ping Jack
    ;
    Ruzairi Abdul Rahim
    ;
    Zulkarnay Zakaria
    ;
    Vernoon Ang Wei Neing
    ;
    Lean Thiam Siow
    Microwave frequency has the potential to assist and improve forest product industry in terms of quality and quantity. Consequently, it has been selected to perform non-destructive inspection on wood which is defected or contains resin internally. This paper describes an experiment to determine the relationship between the attenuation of microwave signals and the different diameters of the holes in tree trunks. This analysis can be used as a reference for an optimal setup for a new microwave tomography aimed at the inspection of valuable wood trunks.