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All Journal International Journal of Electrical and Computer Engineering IAES International Journal of Robotics and Automation (IJRA) Bulletin of Electrical Engineering and Informatics Indonesian Journal of Electrical Engineering and Computer Science
Siti Halma Johari
Universiti Teknikal Malaysia Melaka
Automotive Engineering Computer Science & IT Electrical & Electronics Engineering

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CMOS ring oscillator delay cell performance: a comparative study D. A. Hadi; A. Z. Jidin; N. Ab Wahab; Madiha Z.; Nurliyana Abd Mutalib; Siti Halma Johari; Suziana Ahmad; M. Nuzaimah
International Journal of Electrical and Computer Engineering (IJECE) Vol 9, No 3: June 2019
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (529.147 KB) | DOI: 10.11591/ijece.v9i3.pp1757-1764

Abstract

A common voltage-controlled oscillator (VCO) architecture used in the phase locked loop (PLL) is the ring oscillator (RO). RO consist of number of inverters cascaded together as the input of the first stage connected to the output of the last stage. It is important to design the RO to be work at desired frequency depend on application with low power consumption. This paper presents a review the performance evaluation of different delay cell topologies the implemented in the ring oscillator. The various topologies analyzed includes current starved delay cell, differential delay cell and current follower cell. Performance evaluation includes frequency range, frequency stability, phase noise and power consumption had been reviewed and comparison of different topologies has been discussed. It is observed that starved current delay cell have lower power consumption and the different of the frequency range is small as compared to other type of delay cell.
Fuzzy Takagi-Sugeno Method in Microcontroller Based Water Tank System Nur Maisarah Mohd Sobran; Munirah Mohd Salmi; Mohd Bazli Bahar; Md Nazri Othman; Siti Halma Johari
IAES International Journal of Robotics and Automation (IJRA) Vol 7, No 1: March 2018
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (506.022 KB) | DOI: 10.11591/ijra.v7i1.pp1-7

Abstract

This paper present the performance of Fuzzy logic controller in maintain level of water in water tank system. The mathematical modelling was developed to get the initial idea of the system performance. Later, the prototype of water tank system were constructed and tested to get the real time results. The Takagi-Sugeno “on” and “off” interference technique method was implemented due to the control limitation of the pump motor that being used in the experimental setup. The fuzzy logic controller was realized by embedded the algorithm in microcontroller of the water tank system. The experimental results show acceptable level of water within the range of 18cm to 20.5cm and settling time 59 seconds with 20 cm set point.
Development of mobile robot for measuring distance using optical quadrature encoder Madiha Zahari; NurliyanaAbd Mutalib; Nurnadia Natasya Affendi; N. Hashim; D. A. Hadi; Siti Halma Johari; N. Ab Wahab; Suziana Ahmad
Indonesian Journal of Electrical Engineering and Computer Science Vol 18, No 2: May 2020
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.11591/ijeecs.v18.i2.pp745-749

Abstract

This paper describes the design and development of a measuring tool using a mobile robot. At present, contractors are measuring distances using measuring tape which has few limitations. This includes using of another manpower or a marking flag. The Robot Measuring System is designed to measure distances at multiple conditions such as smooth and rough surface. An optical quadrature encoder is used as a sensor to measure the distances while a program is installed in Arduino Uno for reading and data collection. Graphical User Interface (GUI) was created using Android software so that the movement of the robot can be controlled using a smartphone within a Bluetooth range. An experiment was conducted to test the reliability in terms of accuracy and precision. The best accuracy and precision were obtained when the robot speed is at 90 cm/s on the plain tiles, 80 cm/s on the tar road and 90 cm/s on the grass surface. The robot speed needs to be adjusted accordingly based on the surfaces in order to get an accurate result. This paper proved that the robot measuring system was successfully designed, implemented and analyzed.
A novel examination of limonene detection using plastic fiber optic sensors and the tapered approach Thanigai Anbalagan; Hazura Haroon; Hazli Rafis Abdul Rahim; Siti Halma Johari; Siti Khadijah Idris@ Othman; Hanim Abdul Razak; Maisara Othman
Bulletin of Electrical Engineering and Informatics Vol 12, No 2: April 2023
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.11591/eei.v12i2.4379

Abstract

A novel tapered plastic optic fiber (POF) biosensor is proposed and demonstrated for monitoring limonene in different concentrations. The mechanism of this device is based on an increase in the light transmission of a sensor submerged in a higher-concentration limonene solution, which also reflects an increase in the refractive index of the sensor. The tapered POF was fabricated using the chemical etching method to accomplish different waist diameters of 0.6 mm, 0.55 mm, and 0.5 mm, with a fiber length of 10 cm and a 2 cm sensing region. An Arduino integrated development environment (IDE) program was used to drive the voltage values from the photodetectors to obtain the measurements. As the limonene concentration solution varied from 20% to 100%, the output voltage of the sensor increased linearly, showing a sensitivity of 0.295 V/%, 0.33 V/%, and 0.46 V/% for tapered waist diameters of 0.6 mm, 0.55 mm, and 0.5 mm, respectively. The proposed sensor is a low-cost solution measurement option with high sensitivity, while it also involves a simple and easy fabrication technique.
Co-Authors A. Z. Jidin D. A. Hadi Hanim Abdul Razak Hazli Rafis Abdul Rahim Hazura Haroon M. Nuzaimah Madiha Z. Madiha Zahari Maisara Othman Md Nazri Othman Mohd Bazli Bahar Munirah Mohd Salmi N. Ab Wahab N. Hashim Nur Maisarah Mohd Sobran Nurliyana Abd Mutalib NurliyanaAbd Mutalib Nurnadia Natasya Affendi Siti Khadijah Idris@ Othman Suziana Ahmad Thanigai Anbalagan