Khairul Hamimah Abas

An improved hybrid of particle swarm optimization and the gravitational search algorithm to produce a kinetic parameter estimation of aspartate biochemical pathways

Mathematical modelling is fundamental to understand the dynamic behavior and regulation of the biochemical metabolisms and pathways that are found in biological systems. Pathways are used to describe complex processes that involve many parameters. It is important to have an accurate and complete set of parameters that describe the characteristics of a given model. However, measuring these parameters is typically difficult and even impossible in some cases. Furthermore, the experimental data are often incomplete and also suffer from experimental noise. These shortcomings make it challenging to identify the best-fit parameters that can represent the actual biological processes involved in biological systems. Computational approaches are required to estimate these parameters. The estimation is converted into multimodal optimization problems that require a global optimization algorithm that can avoid local solutions. These local solutions can lead to a bad fit when calibrating with a model. Although the model itself can potentially match a set of experimental data, a high-performance estimation algorithm is required to improve the quality of the solutions. This paper describes an improved hybrid of particle swarm optimization and the gravitational search algorithm (IPSOGSA) to improve the efficiency of a global optimum (the best set of kinetic parameter values) search. The findings suggest that the proposed algorithm is capable of narrowing down the search space by exploiting the feasible solution areas. Hence, the proposed algorithm is able to achieve a near-optimal set of parameters at a fast convergence speed. The proposed algorithm was tested and evaluated based on two aspartate pathways that were obtained from the BioModels Database. The results show that the proposed algorithm outperformed other standard optimization algorithms in terms of accuracy and near-optimal kinetic parameter estimation. Nevertheless, the proposed algorithm is only expected to work well in small scale systems. In addition, the results of this study can be used to estimate kinetic parameter values in the stage of model selection for different experimental conditions.

A Kalman Filter approach to PCB drill path optimization problem

Drill path optimization problem is an important problem in holes drilling with computer numerically controlled (CNC) machine. Due to the exponential increase in the number of possible solutions when the number of holes to be drilled increase, the metaheuristic optimization algorithm seems to be a good choice in solving this type of optimization problem. This paper presents a Kalman Filter approach in solving printed circuit board (PCB) routing problem by using the Simulated Kalman Filter (SKF) algorithm. The experimental results are compared with those obtained by swarm intelligence approach, which are the Particle Swarm Optimization (PSO) variants, Ant Colony System (ACS) and Cuckoo Search (CS). The implementation proves to be effortless with good global convergence capability.

Initial Study On The Implementation Of Reflection Method In Ultrasonic Tomography

Matlamat utama projek ini adalah untuk mereka bentuk suatu sistem pengimbas ultrasonik dengan menggunakan kaedah pantulan yang dijana dan diterima oleh alatan ultrasonik yang lazim digunakan di dalam bidang perubatan. Disebabkan oleh kos yang tinggi dan konfigurasi yang rumit bagi sesetengah alat-alat perubatan yang berjenama seperti Philips dan Brauns, sistem pengimbas ultrasonik yang direkabentuk dalam projek ini adalah berhasrat untuk mengurangkan kos dan juga memudahkan konfigurasi. Pada asasnya, sistem pengimbas ultrasonik terdiri daripada dua bahagian; pemancar dan penerima. Dalam projek ini, satu mikropengawal pengimbas ultrasonik perubatan yang telah dipilih. Isyarat pantulan yang dikesan penerima pengimbas ultrasonik perubatan diperhatikan dengan menggunakan osiloskop digital. Sistem pengimbas yang direka kemudian diuji dengan mengimbas sebuah betik. Kata kunci: Tomography ultrasonik; pantulan; gambaran perubatan; pengimbas ultrasonik; pendekatan secara eksperimen The main purpose of this project is to design an ultrasonic scanner system which implements the reflection method through a medical ultrasound probe. Due to the high–cost and complex configuration of some of the well–known names in medical devices; such as Philips, and Brauns, the ultrasonic scanner system in this project is aimed to be cost effective and simple. Basically, the ultrasonic scanner system consists of two parts; the transmitter and the receiver. In this project, a PIC microcontroller was used in the transmitter circuit in order to produce a 2 MHz signal to excite the 2.25 MHz ultrasonic transmitter that exists in the medical ultrasound probe that had been selected, whereas the output or the reflected signal was obtain by tapping at the receiver of the medical ultrasound probe and was observed by using a digital oscilloscope. The ultrasonic scanner system was later tested by scanning a papaya. This project was verified by obtaining the reflected signals that resulted from the papaya scanning tests. Key words: Ultrasonic tomography; reflective; medical imaging; ultrasound probe; experimental approach