Now showing 1 - 10 of 33
Thumbnail Image
Publication

Development of the Educational Tool for Optimized Algorithm Model Using MATLAB GUI

2021-01-01 , Aunkaew S. , Tantiviwat S. , Siti Zuraidah Ibrahim

Optimization algorithms are mathematical functions that are widely used to solve objective function problems through maximization or minimization. Typically, students at the beginner level face difficulties in understanding the complex mathematical solutions used in optimization algorithms. This paper presents an educational graphical user interface (GUI) for simulation of various topology optimization algorithms that users can use to explore the behavior of local search (LS), tabu search (TS) and particle swarm optimization (PSO) algorithms. The GUI is created using the MATLAB GUIDE tool, which acts as a front-end interface that can be used for teaching as well as learning. Benchmark functions such as the De Jong first function (DF), the Griewank function (GF), the Himmelblau function (HF) and the Periodic function (PF) were used to validate the investigated optimization algorithms. The developed GUI has features where the user can enter functions, define boundary limits, specify solver parameters and select the type of output display. The results of the instance HF function shown using the GUI optimization tool are in good agreement with the benchmark function.

Thumbnail Image
Publication

Development of six-port baseband processing system for short range radar based sensor

2017-01-03 , Nurul Ainun Zulkifli , Nazuhusna Khalid , Siti Zuraidah Ibrahim , Tan G.

This paper presents the development of the six-port baseband processing system for short range radar based sensor. Short range radar involved in many applications such as the used in the automotive system. The analog baseband circuit commercially exists nowadays, but it a little bit bulky and expensive. In this paper, the design of a RF power detector using microstrip technique is presented. The design of diode detector circuit is simulated using Keysight ADS software tool. The design of the diode detector includes the matching network, RF choke and the low pass matching. When the design of diode detector completed, the development of baseband processing system is accomplished using microcontroller board. The algorithm of obtaining Direction of Arrival (DOA) phase wave is executed using microcontroller board. The details of the theory, simulation and results are presented in this paper.

Thumbnail Image
Publication

Miniature microstrip bandpass filters based on quadruple-mode resonators with less via

2017-05-03 , Sugchai Tantiviwat , Mohammad Shahrazel Razalli , Siti Zuraidah Ibrahim

This article aims to design of microstrip resonators in order to reduce size of microstrip bandpass filters in wireless communication systems. Characterized by both theoritical investigation and full-wave simulation, the proposed bandpass filters are designed consist of dual-band bandpass filters and quadruple mode bandpass filters with miniaturized size. The proposed filter is found to have benefits such that the even-mode resonant frequencies can be flexibly controlled while the odd-mode resonant frequency is reserved for the fundamental frequency. Since the structure of resonators is realized using common via holes, the difficulty and complexity of the fabrication process can be shortened. In order to achieve compact size, the total number of resonators is reduced so that the implemented resonators only occupy a small area.

Thumbnail Image
Publication

Tomato Diseases Classification Using Extreme Learning Machine

2023-10-06 , Xian T.S. , Ruzelita Ngadiran , Iszaidy Ismail , Amiza Amir , Siti Zuraidah Ibrahim , Taha T.B.

Plant disease classification is essential to the agriculture industry. In this work, a tomato disease classification using Extreme Learning Machine (ELM) with image-based features. Extreme Learning Machine (ELM), a classification algorithm with a single layer feed-forward neural network where it can be combined with few activation functions. The image features as the input where the image is pre-processed via HSV colour space and extracted using Haralick textures, colour moments and HSV histogram. The features are then loaded in the ELM classifier to perform the ELM training and testing. The accuracy result of ELM classification is then analysed after the validation. The dataset used for disease detection is tomato plant leaves which is a subset of the Plant-Village dataset. The results produced from the ELM demonstrate an accuracy of around 84.94% which is comparable to classifiers such as the Support Vector Machine and Decision Tree.

Thumbnail Image
Publication

Compact multilayer wideband symmetric five-port reflectometer

2017-04-01 , Samir Salem Al-Bawri , Mohd Faizal Jamlos , Siti Zuraidah Ibrahim , Syed Alwee Aljunid Syed Junid

This article presents a new design of a wideband, compact, and low-cost symmetric five-port reflectometer (5PR). The proposed 5PR features a wide operational bandwidth of 3240 MHz (about 162% centered at 2 GHz). Five-symmetric branch-lines consist of SCURVE, STEE, SLIN, and Term were designed and optimized to achieve an equivalent value of 78 dB for S11, S22, S33, S44, and S55 at center frequency of 2 GHz. Such consistent value between those S-parameters proven a perfect matching impedance are successfully obtained by proposed symmetric 5PR even own a bandwidth as high as 162%. Moreover, the simulated and measured results show the proposed 5PR has realized magnitude of ≈ 0 dB (S11), 0.5 (S12, S13, S14, S15, S21, S23 … S54) as well as phase relative error of 120° which in parallel to theoretical values. With all capabilities mentioned, the proposed 5PR is a promising candidate to be installed in a microwave imaging system for biomedical applications in the future. © 2017 Wiley Periodicals, Inc. Microwave Opt Technol Lett 59:802–805, 2017.

Thumbnail Image
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.

Thumbnail Image
Publication

Stochastic pricing formulation for hybrid equity warrants

2022-01-01 , Roslan T.R.N. , Karim S. , Siti Zuraidah Ibrahim , Jameel A.F. , Yahya Z.R.

A warrant is a financial agreement that gives the right but not the responsibility, to buy or sell a security at a specific price prior to expiration. Many researchers inadvertently utilize call option pricing models to price equity warrants, such as the Black Scholes model which had been found to hold many shortcomings. This paper investigates the pricing of equity warrants under a hybrid model of Heston stochastic volatility together with stochastic interest rates from Cox-Ingersoll-Ross model. This work contributes to exploration of the combined effects of stochastic volatility and stochastic interest rates on pricing equity warrants which fills the gap in the current literature. Analytical pricing formulas for hybrid equity warrants are firstly derived using partial differential equation approaches. Further, to implement the pricing formula to realistic contexts, a calibration procedure is performed using local optimization method to estimate all parameters involved. We then conducted an empirical application of our pricing formula, the Black Scholes model, and the Noreen Wolfson model against the real market data. The comparison between these models is presented along with the investigation of the models’ accuracy using statistical error measurements. The outcomes revealed that our proposed model gives the best performance which highlights the crucial elements of both stochastic volatility and stochastic interest rates in valuation of equity warrants. We also examine the warrants’ moneyness and found that 96.875% of the warrants are in-the-money which gives positive returns to investors. Thus, it is beneficial for warrant holders concerned in purchasing warrants to elect the best warrant with the most profitable and more benefits at a future date.

Thumbnail Image
Publication

LaundryMama: Humanising Laundry Tasks using Laundry Management System and Laundry-On-Demand Mobile Applications

2020-03-20 , Mei L.Y. , Ku Nurul Fazira Ku Azir , Siti Zuraidah Ibrahim , Saidatul Norlyana Azemi

Laundry Management System and Laundry-On-Demand Mobile Applications are presented in this paper. Using conventional laundry service method, customer is not informed about the laundry process stage, does not have option to arrange the preferred laundry pick up time for the deliveryman to pick up the unwashed laundry from the address provided by customer and the laundry ordering paper forms are often lost in transit between customer and admin. Therefore, a laundry management system software and laundry on demand mobile application is demanded to solve the problems. The software development is performed using an open source developing platform Android Studio IDE and Firebase Real-time Database, Authentication, Cloud Messaging and Cloud Storage. The method used to develop the software is waterfall modelling and two characters are involved, which is admin and customer. The two characters functions are separated in two different applications. A Laundry Management System Software is developed for admin to manage, make order and monitor the business. A Laundry-On-Demand Mobile Application is developed for customer to make order and monitor the order. These both applications can receive notification from each other. The data can be correctly written and read from Firebase Real-time database, Firebase Authentication, Firebase Cloud Storage. The developed software and mobile application are evaluated in term of its functionality.

Thumbnail Image
Publication

Compact low pass filter with deep and wide stopband using H-shaped defected microstrip structure

2017-01-03 , Nur Baya Mohd Hashim , Mohammad Shahrazel Razalli , Siti Zuraidah Ibrahim , Farah Shazuani Mahmu , Nordiana Mohamad Saaid

A deep attenuation level and wide stopband bandwidth, sharp roll-off and low insertion loss in the passband using H-shaped defected microstrip structure (DMS) at open circuit stub resonator (OCSR) of the stepped-impedance low pass filter (SILPF) is presented in this paper. The proposed filter consists of H-shaped that is etching at the microstrip line of OCSR. The OCSR is embedded in the middle of high impedance line of the SILPF. The effect of the applying H-shaped DMS is investigated through parametric studies by comparing H-shaped with Y-shaped and U-shaped. It is observed that the comparison with conventional SILPF shows that the proposed modification filter exhibit a deep and large rejected band of 27 dB attenuation level from 8.21 GHz to 23.16 GHz up to 3 fc. The proposed filter also offers sharp roll-off at 7.31 GHz cut-off frequency and maximum ripple value in the range of DC to 6 GHz is less than 0.35 dB.

Thumbnail Image
Publication

Development of branchline coupler using parallel coupled transmission lines

2017-01-03 , Rahim N.H.A. , Rasid R. , Siti Zuraidah Ibrahim , Nazuhusna Khalid , Mohammad Shahrazel Razalli , Siang T.G.

This paper investigates the development of branchline coupler using parallel coupled transmission lines on planar microstrip using CST Studio Suite 2010 design tool. This project operates within 4 GHz to 8 GHz frequency band. Two designs are proposed in this project which are basic branch line coupler and branch line coupler with parallel line feeding technique. The main purpose of this study is to improve bandwidth while compare the performance of both designed coupler. The designs are then investigated using CST Microwave Studio simulation tool. The designs are fabricated on microstrip printed circuit board and measured using vector network analyzer. The simulated and experimental results of both developed couplers are compared and analyzed. The overall simulated percentage bandwidth of the proposed coupler is covered from 4 to 8 GHz with percentage bandwidth of 32.32%.