Zulkarnay Zakaria
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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

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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.

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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.

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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.

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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.

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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.

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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.

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Modelling of ultrasound tomography technique for Glass Fibre Reinforced Epoxy (GFRE) composites liquid transportation pipeline

2017-03-13 , Lean Thiam Siow , Mohd Hafiz Fazalul Rahiman , Mohd Shukry Abdul Majid , Ruzairi Abdul Rahim , Zulkarnay Zakaria , Thomas W.K.T. , Vernoon Ang Wei Neng

The purpose of this paper is to model the ultrasonic tomography on the E-glass fibre reinforced epoxy composite pipe for process monitoring and control. Finite element software and mathematical estimation were applied to model and study the ultrasound wave propagation, especially the reflection and transmission coefficient. While there is a significant result achieved between mathematical estimation and finite element analysis with maximum percentage distinctly in 2.33.

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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.

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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.

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Non-invasive breast cancer assessment using magnetic induction spectroscopy technique

2017-01-01 , Hang Jo Ann , Lynn Sim Su-Shi , Zulkarnay Zakaria

Breast cancer has become one of the main concern for all human being especially women. Most breast cancer happen in women because women have denser breast tissues than men and breast cells of women are always exposed to changes in hormones, including oestrogen, which increase the risk for women to get breast cancer. The common breast cancer imaging modalities have their own limitations which could be one of the reason for increasing number of breast cancer reported beside unawareness for the disease from the patients themselves. Therefore, early detection and treatment which involve non-invasive technique is more encouraging for its lesser physical and mental harm to patients. This paper describes single channel magnetic induction technique as an alternative method for breast cancer assessment. The simulation was done to investigate the most feasible shape of sensor coil and best range of frequency value to detect breast cancer. The study has found that the circular coil performs better than square coil and the applied frequency range must be high for detecting the conductivity property distribution of breast tissues. The study has proven that magnetic induction spectroscopy technique can be used for breast cancer assessment.

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