Mimi Ramli - Academia.edu (original) (raw)

Papers by Mimi Ramli

Research paper thumbnail of Determination of OCS Mast Offset in Johore Bahru Sentral for Gemas-Johor Electrified Double Track Project

Journal of Advanced Research in Applied Sciences and Engineering Technology, May 7, 2024

Research paper thumbnail of The Optimal Span Length of the Overhead Catenary System for the Gemas-Johor Bahru Electrified Double Track Project

Journal of Advanced Research in Applied Sciences and Engineering Technology, Apr 17, 2024

Research paper thumbnail of Antenna Array Performance in Microwave Imaging Technique for Brain Tumor Detection

International Journal of Emerging Technology and Advanced Engineering

Recent advancements in microwave tomography (MT) imaging studies have stimulated interest in ante... more Recent advancements in microwave tomography (MT) imaging studies have stimulated interest in antenna array development for medical imaging. An antenna and a model of the human head are required for the medical MT system, particularly in detecting brain tumors. Previous studies have shown that antenna arrays are more reliable as compared to a single element of patch antenna in detecting brain tumors. In this study, a single patch antenna is first designed to work at 3.2GHz using CST Studio software. To evaluate the effectiveness of antenna arrays in microwave imaging systems, the patch antenna is then improved into a 2x1 and 4x1 array. The gain, directivity, return loss (S11), Voltage Standing Wave Ratio (VSWR), and bandwidth are compared between single and arrays of antenna models. It has been proved that 2x1 and 4x1 antenna arrays resulted in higher performance. With a maximum gain of 7.11 dB, the 4x1 rectangle patch antenna has 11.3 dBi directivity, -13.88 dB return loss, and 91.1...

Research paper thumbnail of Visual Performance and Motorcycle Safety-Related Impacts of Various High Beam Headlight Intensities

Journal of the Society of Automotive Engineers Malaysia

In Malaysia, the three main types of motorcycle accidents include collision with passenger cars, ... more In Malaysia, the three main types of motorcycle accidents include collision with passenger cars, collision with other motorcycles and single-motorcycle accidents. An accident may occur due to the lack of road design consistency and visibility where most drivers make more errors in the absence of geometric features. One of the most important barriers to the more frequent use of high beam headlight is the length of visibility of the headlight beam in relation to the stopping distance of a vehicle. Furthermore, it is crucial to evaluate the current limits on the luminous intensity of high beam headlights that is considered visible for a driver to come to a stop. Therefore, this first stage study summarizes and investigates the stopping sight distances, braking distances that allow for the evaluation of the vehicle's performance to increase the capability of both the driver and vehicle with regard to safety. A total of ten experiments were carried out with a passenger car, the Perod...

Research paper thumbnail of A Preliminary Result on Electrical capacitance tomography for Gas-solid flow in pneumatic conveyor system

ELEKTRIKA- Journal of Electrical Engineering, Oct 15, 2021

Research paper thumbnail of Investigation of relaxation factor in landweber iterative algorithm for electrical capacitance tomography

2017 IEEE International Conference on Imaging Systems and Techniques (IST), 2017

It is crucial to select a suitable relaxation factor in iterative image reconstruction algorithms... more It is crucial to select a suitable relaxation factor in iterative image reconstruction algorithms (e.g. Landweber iterative algorithm) for electrical capacitance tomography (ECT) because it affects the convergence. By simulation, it is found notably that the relaxation factor should be selected adaptively according to the sensor structure (e.g. the number of electrodes) and the permittivity distribution in capacitance measurements. With different number of electrodes and four typical permittivity distributions, the relaxation factor and the related convergence are investigated in consideration of the change in relative image error. It is shown that the relaxation factor can be chosen based on the upper boundary of all relaxation factors. The conclusions in this paper can be used for practical industrial processes, regarding the adaptive selection of relaxation factor and the number of iterations needed.

Research paper thumbnail of Image reconstruction with different sensitivity maps generated with different background

2016 IEEE International Conference on Imaging Systems and Techniques (IST), 2016

Most researchers working on electrical capacitance tomography (ECT) use a set of generic sensitiv... more Most researchers working on electrical capacitance tomography (ECT) use a set of generic sensitivity maps, based on empty background. The aim of this study is to investigate whether or not different sensitivity maps should be used for imaging different dielectric materials. For this purpose, different sensitivity maps are generated by dot multiplication of electric fields with different permittivity backgrounds. To see the effect of different sensitivity maps on image reconstruction, stratified and annular distributions are chosen for simulation with a 12-electrode ECT sensor. The reconstructed images are evaluated by the image error. To verify the simulation results, experiments are carried out. Preliminary results show that the generic sensitivity maps based on empty background are suitable for image reconstruction in most cases.

Research paper thumbnail of Accident prediction model by relating integrated design consistency model

International Journal of Integrated Engineering, 2020

The number road accident kept rising in every year in Malaysia. In early 2016, Johor has been men... more The number road accident kept rising in every year in Malaysia. In early 2016, Johor has been mentioned as the among highest-ranking road accident at hazard road locations. The main accidents occur are a road accident with passenger cars, road accident with other motorcycles and single-motorcycle road accidents. Furthermore, the problem road accident on hazard road location are still unsolved, especially for main road accident types of vehicle; motorcycles and cars. The study location segments were selected at Johor Federal Route 50; KM1-KM5. Therefore, this study using an accident prediction model by relating integrated design consistency model, through a comprehensive speed characteristic using a global positioning system and based on an operating profile to develop a continuous speed profile between motorcycles and cars and to determine design consistency models. Poisson model is used to relate road design consistency models and accident rates to evaluate the impact of design consistency with road safety.

Research paper thumbnail of Effect of electrode-to-gap ratio on electrical capacitance tomography images

2016 IEEE International Conference on Imaging Systems and Techniques (IST), 2016

In electrical capacitance tomography (ECT), the electrode-to-gap ratio (EGR) of a sensor is one o... more In electrical capacitance tomography (ECT), the electrode-to-gap ratio (EGR) of a sensor is one of the design parameters. It is commonly believed that a larger EGR would result in higher quality of tomographic images. However, no quantitative study has been reported. In this paper, the effect of EGR on ECT imaging is investigated quantitatively. ECT sensors with different EGR of 1:1, 2:1, 3:1, 4:1, 5:1, 6:1, 7:1, 8:1, 9:1 and 10:1 are simulated and images are reconstructed using linear back projection (LBP) and Landweber iteration algorithms for two typical permittivity distributions. The relative image errors are calculated against the real permittivity distributions. The sensitivity distributions of the ECT sensors with different EGR are analyzed and compared. The results show that the effect of ECR on ECT imaging can be neglected when it is larger than 6:1.

Research paper thumbnail of Microwave tomography sensing for potential agarwood trees imaging

Computers and Electronics in Agriculture, 2019

Research paper thumbnail of An Electrical Capacitance Tomography Sensor With Variable Diameter

IEEE Sensors Journal, 2017

Research paper thumbnail of Adaptive Selection of Relaxation Factor in Landweber Iterative Algorithm

IEEE Sensors Journal, 2017

Research paper thumbnail of Imaging wet granules with different flow patterns by electrical capacitance tomography and microwave tomography

Measurement Science and Technology, 2016

The moisture content of granules in fluidised bed drying, granulation and coating processes can t... more The moisture content of granules in fluidised bed drying, granulation and coating processes can typically be between 1%~25%, resulting in the change of permittivity and conductivity during the processes. Electrical capacitance tomography (ECT) has been used for this purpose, but has a limit because too much water can cause a problem in capacitance measurement. Considering that microwave tomography (MWT) has a wide range of frequency (1~2.5 GHz) and can be used to measure materials with high permittivity and conductivity, the objective of this research is to combine ECT and MWT together to investigate the solids concentration with different moisture content and different flow patterns. The measurement results show that both ECT and MWT are functions of moisture content as well as flow patterns, and their measurements are complementary to each other. This is the first time that these two tomography modalities have been combined together and applied to image the complex solids distribution. The obtained information may be used for the process control of fluidised bed drying, granulation and coating to improve operation efficiency.

Research paper thumbnail of Smart Data Recognition System For Seven Segment LED Display

International Journal of Human and Technology Interaction (IJHaTI), Oct 31, 2020

Research paper thumbnail of An Investigation of Microwave Tomography Technique to Detect Brain Tumour Through Cross-Section Imaging at Frequency 0.5 GHz to 1.5 GHz

Journal of Advanced Industrial Technology and Application, 2021

The growing significance of cancerous tissue including brain tumour requires a fast and efficient... more The growing significance of cancerous tissue including brain tumour requires a fast and efficient technology detection. The most current technologies being applied for brain imaging system are Computed Tomography (CT) scan and Magnetic Resonance Imaging (MRI). Whilst these two detection applications are very well established, both systems are expensive, time and space consuming, and raise safety issues to patients due to the radiation and strong magnetic effects. This research aims to assess the feasibility and potential performance of microwave tomography (MWT) for brain imaging with a particular focus on brain tumour detection. The study was conducted using Finite Element Model software, COMSOL Multiphysics to develop a 2D modelling of an antenna array and measure the scattered electric field by solving forward problem. MATLAB software will be used as an inverse problem solver to reconstruct 2D images of the tumour by using Linear Back Projection (LBP) algorithm.

Research paper thumbnail of Multiphase flow measurement by electrical capacitance tomography

2011 IEEE International Conference on Imaging Systems and Techniques, 2011

Abstract Currently, almost all gas-oil-water multiphase flow meters used in the oil industry, for... more Abstract Currently, almost all gas-oil-water multiphase flow meters used in the oil industry, for production monitoring and/or well testing, rely on radioactive source emitting gamma rays. These meters are, however, expensive and sometimes have logistic issues in ...

Research paper thumbnail of Determination of OCS Mast Offset in Johore Bahru Sentral for Gemas-Johor Electrified Double Track Project

Journal of Advanced Research in Applied Sciences and Engineering Technology, May 7, 2024

Research paper thumbnail of The Optimal Span Length of the Overhead Catenary System for the Gemas-Johor Bahru Electrified Double Track Project

Journal of Advanced Research in Applied Sciences and Engineering Technology, Apr 17, 2024

Research paper thumbnail of Antenna Array Performance in Microwave Imaging Technique for Brain Tumor Detection

International Journal of Emerging Technology and Advanced Engineering

Recent advancements in microwave tomography (MT) imaging studies have stimulated interest in ante... more Recent advancements in microwave tomography (MT) imaging studies have stimulated interest in antenna array development for medical imaging. An antenna and a model of the human head are required for the medical MT system, particularly in detecting brain tumors. Previous studies have shown that antenna arrays are more reliable as compared to a single element of patch antenna in detecting brain tumors. In this study, a single patch antenna is first designed to work at 3.2GHz using CST Studio software. To evaluate the effectiveness of antenna arrays in microwave imaging systems, the patch antenna is then improved into a 2x1 and 4x1 array. The gain, directivity, return loss (S11), Voltage Standing Wave Ratio (VSWR), and bandwidth are compared between single and arrays of antenna models. It has been proved that 2x1 and 4x1 antenna arrays resulted in higher performance. With a maximum gain of 7.11 dB, the 4x1 rectangle patch antenna has 11.3 dBi directivity, -13.88 dB return loss, and 91.1...

Research paper thumbnail of Visual Performance and Motorcycle Safety-Related Impacts of Various High Beam Headlight Intensities

Journal of the Society of Automotive Engineers Malaysia

In Malaysia, the three main types of motorcycle accidents include collision with passenger cars, ... more In Malaysia, the three main types of motorcycle accidents include collision with passenger cars, collision with other motorcycles and single-motorcycle accidents. An accident may occur due to the lack of road design consistency and visibility where most drivers make more errors in the absence of geometric features. One of the most important barriers to the more frequent use of high beam headlight is the length of visibility of the headlight beam in relation to the stopping distance of a vehicle. Furthermore, it is crucial to evaluate the current limits on the luminous intensity of high beam headlights that is considered visible for a driver to come to a stop. Therefore, this first stage study summarizes and investigates the stopping sight distances, braking distances that allow for the evaluation of the vehicle's performance to increase the capability of both the driver and vehicle with regard to safety. A total of ten experiments were carried out with a passenger car, the Perod...

Research paper thumbnail of A Preliminary Result on Electrical capacitance tomography for Gas-solid flow in pneumatic conveyor system

ELEKTRIKA- Journal of Electrical Engineering, Oct 15, 2021

Research paper thumbnail of Investigation of relaxation factor in landweber iterative algorithm for electrical capacitance tomography

2017 IEEE International Conference on Imaging Systems and Techniques (IST), 2017

It is crucial to select a suitable relaxation factor in iterative image reconstruction algorithms... more It is crucial to select a suitable relaxation factor in iterative image reconstruction algorithms (e.g. Landweber iterative algorithm) for electrical capacitance tomography (ECT) because it affects the convergence. By simulation, it is found notably that the relaxation factor should be selected adaptively according to the sensor structure (e.g. the number of electrodes) and the permittivity distribution in capacitance measurements. With different number of electrodes and four typical permittivity distributions, the relaxation factor and the related convergence are investigated in consideration of the change in relative image error. It is shown that the relaxation factor can be chosen based on the upper boundary of all relaxation factors. The conclusions in this paper can be used for practical industrial processes, regarding the adaptive selection of relaxation factor and the number of iterations needed.

Research paper thumbnail of Image reconstruction with different sensitivity maps generated with different background

2016 IEEE International Conference on Imaging Systems and Techniques (IST), 2016

Most researchers working on electrical capacitance tomography (ECT) use a set of generic sensitiv... more Most researchers working on electrical capacitance tomography (ECT) use a set of generic sensitivity maps, based on empty background. The aim of this study is to investigate whether or not different sensitivity maps should be used for imaging different dielectric materials. For this purpose, different sensitivity maps are generated by dot multiplication of electric fields with different permittivity backgrounds. To see the effect of different sensitivity maps on image reconstruction, stratified and annular distributions are chosen for simulation with a 12-electrode ECT sensor. The reconstructed images are evaluated by the image error. To verify the simulation results, experiments are carried out. Preliminary results show that the generic sensitivity maps based on empty background are suitable for image reconstruction in most cases.

Research paper thumbnail of Accident prediction model by relating integrated design consistency model

International Journal of Integrated Engineering, 2020

The number road accident kept rising in every year in Malaysia. In early 2016, Johor has been men... more The number road accident kept rising in every year in Malaysia. In early 2016, Johor has been mentioned as the among highest-ranking road accident at hazard road locations. The main accidents occur are a road accident with passenger cars, road accident with other motorcycles and single-motorcycle road accidents. Furthermore, the problem road accident on hazard road location are still unsolved, especially for main road accident types of vehicle; motorcycles and cars. The study location segments were selected at Johor Federal Route 50; KM1-KM5. Therefore, this study using an accident prediction model by relating integrated design consistency model, through a comprehensive speed characteristic using a global positioning system and based on an operating profile to develop a continuous speed profile between motorcycles and cars and to determine design consistency models. Poisson model is used to relate road design consistency models and accident rates to evaluate the impact of design consistency with road safety.

Research paper thumbnail of Effect of electrode-to-gap ratio on electrical capacitance tomography images

2016 IEEE International Conference on Imaging Systems and Techniques (IST), 2016

In electrical capacitance tomography (ECT), the electrode-to-gap ratio (EGR) of a sensor is one o... more In electrical capacitance tomography (ECT), the electrode-to-gap ratio (EGR) of a sensor is one of the design parameters. It is commonly believed that a larger EGR would result in higher quality of tomographic images. However, no quantitative study has been reported. In this paper, the effect of EGR on ECT imaging is investigated quantitatively. ECT sensors with different EGR of 1:1, 2:1, 3:1, 4:1, 5:1, 6:1, 7:1, 8:1, 9:1 and 10:1 are simulated and images are reconstructed using linear back projection (LBP) and Landweber iteration algorithms for two typical permittivity distributions. The relative image errors are calculated against the real permittivity distributions. The sensitivity distributions of the ECT sensors with different EGR are analyzed and compared. The results show that the effect of ECR on ECT imaging can be neglected when it is larger than 6:1.

Research paper thumbnail of Microwave tomography sensing for potential agarwood trees imaging

Computers and Electronics in Agriculture, 2019

Research paper thumbnail of An Electrical Capacitance Tomography Sensor With Variable Diameter

IEEE Sensors Journal, 2017

Research paper thumbnail of Adaptive Selection of Relaxation Factor in Landweber Iterative Algorithm

IEEE Sensors Journal, 2017

Research paper thumbnail of Imaging wet granules with different flow patterns by electrical capacitance tomography and microwave tomography

Measurement Science and Technology, 2016

The moisture content of granules in fluidised bed drying, granulation and coating processes can t... more The moisture content of granules in fluidised bed drying, granulation and coating processes can typically be between 1%~25%, resulting in the change of permittivity and conductivity during the processes. Electrical capacitance tomography (ECT) has been used for this purpose, but has a limit because too much water can cause a problem in capacitance measurement. Considering that microwave tomography (MWT) has a wide range of frequency (1~2.5 GHz) and can be used to measure materials with high permittivity and conductivity, the objective of this research is to combine ECT and MWT together to investigate the solids concentration with different moisture content and different flow patterns. The measurement results show that both ECT and MWT are functions of moisture content as well as flow patterns, and their measurements are complementary to each other. This is the first time that these two tomography modalities have been combined together and applied to image the complex solids distribution. The obtained information may be used for the process control of fluidised bed drying, granulation and coating to improve operation efficiency.

Research paper thumbnail of Smart Data Recognition System For Seven Segment LED Display

International Journal of Human and Technology Interaction (IJHaTI), Oct 31, 2020

Research paper thumbnail of An Investigation of Microwave Tomography Technique to Detect Brain Tumour Through Cross-Section Imaging at Frequency 0.5 GHz to 1.5 GHz

Journal of Advanced Industrial Technology and Application, 2021

The growing significance of cancerous tissue including brain tumour requires a fast and efficient... more The growing significance of cancerous tissue including brain tumour requires a fast and efficient technology detection. The most current technologies being applied for brain imaging system are Computed Tomography (CT) scan and Magnetic Resonance Imaging (MRI). Whilst these two detection applications are very well established, both systems are expensive, time and space consuming, and raise safety issues to patients due to the radiation and strong magnetic effects. This research aims to assess the feasibility and potential performance of microwave tomography (MWT) for brain imaging with a particular focus on brain tumour detection. The study was conducted using Finite Element Model software, COMSOL Multiphysics to develop a 2D modelling of an antenna array and measure the scattered electric field by solving forward problem. MATLAB software will be used as an inverse problem solver to reconstruct 2D images of the tumour by using Linear Back Projection (LBP) algorithm.

Research paper thumbnail of Multiphase flow measurement by electrical capacitance tomography

2011 IEEE International Conference on Imaging Systems and Techniques, 2011

Abstract Currently, almost all gas-oil-water multiphase flow meters used in the oil industry, for... more Abstract Currently, almost all gas-oil-water multiphase flow meters used in the oil industry, for production monitoring and/or well testing, rely on radioactive source emitting gamma rays. These meters are, however, expensive and sometimes have logistic issues in ...