Sazali Yaacob

Sazali Yaacob
University of Kuala Lumpur | unikl · Malaysian Spanish Institute

About

366
Publications
133,876
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4,706
Citations
Citations since 2016
26 Research Items
2945 Citations
20162017201820192020202120220100200300400
20162017201820192020202120220100200300400
20162017201820192020202120220100200300400
20162017201820192020202120220100200300400

Publications

Publications (366)
Article
This paper describes the development of Physical Modelling of Series Elastic Actuator for Active Ankle-Foot Orthosis by using Simscape Multibody Link. Active Ankle-Foot Orthosis is essential that can be used for the rehabilitation process to the patient. It is useful in medicine to help a patient who loses their walking ability, due to ankle weakne...
Article
Full-text available
Sleeping on the wheels due to drowsiness is one of the significant causes of death tolls all over the world. The primary reason for the sleepiness is due to lack of sleep and irregular sleep patterns. Several methods such as unobtrusive sensors, vehicle dynamics and obtrusive physiology sensors are used to diagnose drowsiness in drivers. However, t...
Conference Paper
Driver’s drowsiness becomes a prominent factor that causes the growing number of road accident in the past few years and turns out to be perturbing for Malaysian road safety. Driving a vehicle under drowsy circumstance will affect driving performance and alertness deficiency, which ultimately give rise to a higher chance of collision. This research...
Conference Paper
Full-text available
Driver’s drowsiness becomes a prominent factor that causes the growing number of road accident in the past few years and turns out to be perturbing for Malaysian road safety. Driving a vehicle under drowsy circumstance will affect driving performance and alertness deficiency, which ultimately give rise to a higher chance of collision. This research...
Conference Paper
Full-text available
Anticipating such catastrophic road accident is one of the main interest of Malaysian government policies, vehicle manufactures strategies, and research in automotive safety. The vital aspect that causes road accident is a human error due to the behavior of the drivers. This research presents approaches for alertness detection based on the electroe...
Article
Full-text available
Brake system in automobiles are the most importance component for the vehicle to avoid from accident occurrence. Therefore brake system needed to be in a good condition in all time. Hence detection of defect from this system must be detected in advance to avoid any failure. The signal for both good and fault conditions of brake has been simulated i...
Article
Obesity is considered as a major cause of some serious diseases such as diabetes and cardiovascular diseases and it has become epidemic. In the field of medicine and health, the usage of body mass index (BMI) is very popular. There are some limitations in using BMI in determining the repartition of body fat due to the fact that it is a skewed measu...
Article
The aim of the present study is to select a set of higher order spectral features for emotion/stress recognition system. 50 Bispectral (28 features) and Bicoherence (22 features) based higher order spectral features were extracted from speech signal and its glottal waveform. These features were combined with Inter-Speech 2010 features to further im...
Article
A new set of features and feature enhancement techniques are proposed to recognize emotion and stress from speech signal. The speech waveforms and the glottal waveforms (derived from the recorded emotional/stress speech waveforms) were processed by using third order statistics called bispectrum and 28 (14 from speech waveforms and 14 from glottal w...
Chapter
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Accent is a major cause of variability in speaker-independent automatic speech recognition (ASR) systems. Under certain circumstances, this behavioral factor introduces unsatisfactory performance of the systems. Thus, accent analyzer in the preceding stage of the ASR system becomes a promising solution. This paper proposes a multi-resolution approa...
Conference Paper
The impact of this project is two folds-the feasibility study of using 2 RPS (Revolute-Prismatic-Spherical) — 1S (Spherical) parallel robotic as solar tracking to propose for implementing at solar power plant and modelling the structural mechanisms with inverse kinematics formulate by using the Denavit-Hartenberg (DH) method to know the performance...
Conference Paper
This paper presents the analyzed on Earth Centered Inertial (ECI) of Attitude Determination System (ADS) and satellite velocity data of RazakSAT by using analysis method. ADS are one sub-system in satellite as function to control the orientation of satellite relative with inertial references frame. ECI is one of inertial references frame of RazakSA...
Conference Paper
In space, environmental torques exerts continuously on a satellite and may influence and affect the satellite’s attitude dynamics. The relative strength of the various torques will depend on both spacecraft environment and the structure of the spacecraft itself. RazakSAT is the world first remote sensing satellite launched into Near Equatorial Orbi...
Conference Paper
A new method has been implemented based on Dual Tree Complex Wavelet Packet Transform (DT-CWPT) feature extraction for infant cry signal classification. The infant cry signals were decomposed into five levels using DT-CWPT. A total of 124 energy features and 124 Shannon entropy features were extracted from each sub-band. Two classifiers Extreme Lea...
Conference Paper
Automotive industry is market sensitive. The requirements of the industry keep changing due to fluctuating market needs and customer demands. Not all the automotive manufactures maintain a robust supply chain, ensuring quality. Automotive industry is prone to change in material prices, order cancellations, excessive inventory, logistic delays, and...
Conference Paper
One of the challenges faced by automatic facial emotion recognition nowadays is the ability to deal with complicated environmental conditions such as noisy environments. In order to solve this problem, this paper aims to examine facial emotion recognition under noisy environment using empirical mode decomposition (EMD). EMD is a multiresolution tec...
Article
This paper proposes a new hybrid method named SCFE-PNN, which integrates effective subtractive clustering based features enhancement and probabilistic neural network (PNN) classifier, had been introduced for isolated Malay word recognition. The proposed method of subtractive clustering features weighting is used as a data preprocessing tool, which...
Conference Paper
Abstract—This paper highlights on the development of a Ultrasonic Sensor Bank with sixteen pieces 40 kHz ultrasonic sensor (USB-16) mounted on hexadecagonbased plate on a mobile robot to perform real time 2D and 3D mapping. The purpose of this research is to evaluate the capability of USB-16 in providing an accurate map in terms of the walls perime...
Chapter
Accent is fascinating human speech behavior that can be used to mark personal identity and social characteristics of its bearer. However, it also has potential to bias social interaction which includes prestige, job competency and ethnic discrimination. Albeit many successful methods have been deployed in the past to identify a speaker accent, the...
Chapter
Accent problem is a current issue that degrades the intelligibility and performance of speech recognition (ASR) systems. Despite English accents have been extensively researched in the United States, Britain, Australia, China, India, and Singapore, the study of Malaysian English (MalE) is still at infancy. There is till date, very limited evidence...
Article
Adiposity nowadays is one of the most important causes which are responsible for the chronic maladies such as hypertension and diabetes and in the coming years, it is predestined to be responsible for many deaths. The body mass index (BMI) is a useful tool which is common in the field of medicine and experts of the wellbeing to determine whether th...
Conference Paper
This paper describes the usage of sixteen piece 40 kHz ultrasonic sensors, known as Ultrasonic Sensor Bank (USB-16) mounted on a mobile robot platform. The Homogeneous Transformation Matrix (HTM) and trigonometric algorithm is utilized in this research as a wall mapping algorithm. The walls were designed with four types of basic shapes such as rect...
Article
This paper designs and investigates an observer system via Extended Kalman Filter algorithm to estimate the satellite’s Euler angles attitude during the absence of the attitude sensor measurement. This work contributes as a backup or an alternative system during unavailable attitude sensor measurement due to malfunction sensor or for cost reduction...
Article
Nowadays, the application of facial emotion recognition for human-computer interaction (HCI) is becoming an emerging trend. This HCI depends to a large extent on its ability to recognize the facial expression and ability to withstand with various kinds of noise. However, confidence in its ability to provide adequate recognition remains challenging...
Conference Paper
Fatness is a serious health problem worldwide because of the danger factors associated with diseases which cause permanent psychological effect. To classify normal weight, overweight, underweight and obesity, body mass index (BMI) is the most recognized and extensively used measurement. BMI measurement has its limits in some cases like overstatemen...
Article
Full-text available
Attitude determination system (ADS) is a process to control the orientation of satellite to make sure that the orientation of satellite is relative to inertial reference frame such as Earth. Earth Centered Inertial (ECI) is one of reference frame for satellite that determines the attitude in three dimensional spacecraft. Since RazakSAT orbits on ea...
Article
Full-text available
The needs of having locations identification are so important in this technological era. Locations identification has been implemented in so many areas nowadays. The challenge in this system is to identify location in real-time. Here, real-time refers to the process of capturing the location and recognize it at the same time. This research proposes...
Article
In this paper, a dynamic model equation of the RazakSAT® class satellite three flexible solar panels for three-dimensional dynamic studies is developed based on the coupling deformation field. In the model, each solar panel is flexible and attached to the satellite body via a fixed joint where the assumption of Euler-Bernoulli beam is applied for t...
Article
Full-text available
[Purpose] Computational intelligence similar to pattern recognition is frequently confronted with high-dimensional data. Therefore, the reduction of the dimensionality is critical to make the manifold features amenable. Procedures that are analytically or computationally manageable in smaller amounts of data and low-dimensional space can become imp...
Article
Full-text available
Parkinson's Disease (PD) is characterized as the commonest neurodegenerative illness that gradually degenerates the central nervous system. The goal of this review is to come out with a summary of the recent progress of numerous forms of sensors and systems that are related to diagnosis of PD in the past decades. The paper reviews the substantial r...
Article
Full-text available
The standard speech feature extractors such as Mel-Frequency Cepstral Coefficients (MFCC) and Linear Prediction Coefficients (LPC) fail to perform well under noisy conditions. In this paper two noise less-susceptible features are proposed to mitigate the deficiency of MFCC and LPC. Statistical descriptors of Mel-Bands Spectral Energy (MBSE) is appl...
Article
Full-text available
To date, Malaysian English (MalE) accents arises from different ethnics of its populace are scarcely investigated using empirical methods that give a decisive conclusion to treat MalE as either uniform or non-uniform variety. The popularly used Mel-Frequency Cepstral Coefficients (MFCC) and Linear Prediction Coefficients (LPC) as feature extractors...
Conference Paper
The accuracy of control and estimation tasks can strongly depend on the accuracy of the underlying model. In space, there are many sources that contribute to the uncertainty in the dynamics model of satellite attitude. Hence, the aim of this paper is to update the dynamical attitude model using grey modeling technique. In this paper, the residual e...
Conference Paper
The diagnostic process of facial paralysis requires qualitative assessment for the classification and treatment planning. This result is inconsistent assessment that potential affect treatment planning. We developed a facial-paralysis diagnostic system based on 3D reconstruction of RGB and depth data using a standard structured-light camera – Kinec...
Conference Paper
Full-text available
Human Motion Analysis (HMA) system has been one of the major interests among researchers in the field of computer vision, artificial intelligence and biomedical engineering and sciences. This is due to its wide and promising biomedical applications, namely, bio-instrumentation for human computer interfacing and surveillance system for monitoring hu...
Article
In the recent years, researchers are focusing to improve the accuracy of speech emotion recognition. Generally, high emotion recognition accuracies were obtained for two-class emotion recognition, but multi-class emotion recognition is still a challenging task . The main aim of this work is to propose a two-stage feature reduction using Principal C...
Conference Paper
Full-text available
Parkinson’s disease (PD) is placed as second supreme neurodegenerative sicknesses after Alzheimer’s. It is characterized by dopaminergic deficiencies in the mid brain that impair motor function. Due to rise in proportion of elderly people the number of patients with Parkinson (PWP) are expected to increase for the coming 25 years. Until now, there...
Article
In the recent years, many research works have been published using speech related features for speech emotion recognition, however, recent studies show that there is a strong correlation between emotional states and glottal features. In this work, Mel-frequency cepstralcoefficients (MFCCs), linear predictive cepstral coefficients (LPCCs), perceptua...
Data
This study examines the design of heat exchanger made of copper tube for cooling electric vehicle car battery system and the effects of base fluid and nanofluid (as coolants) channeling inside the heat exchanger to increase heat transfer between the compartment of the electric vehicle car and the heat exchanger and comparison between them. The nano...
Article
Full-text available
Recently, researchers have paid escalating attention to studying the emotional state of an individual from his/her speech signals as the speech signal is the fastest and the most natural method of communication between individuals. In this work, new feature enhancement using Gaussian mixture model (GMM) was proposed to enhance the discriminatory po...
Article
Full-text available
This study examines the design of heat exchanger made of copper tube for cooling electric vehicle car battery system and the effects of base fluid and nano-fluid (as coolants) channeling inside the heat exchanger to increase heat transfer between the compartment of the electric vehicle car and the heat exchanger and comparison between them. The nan...
Article
This paper proposes a new approach of using nonlinear technique, two-dimensional empirical mode decomposition (2DEMD) and PCA plus LDA for facial emotion recognition. The EMD is a non-parametric data-driven analysis tools which decomposes any nonlinear and non-stationary signals into a number of intrinsic mode functions (IMFs). In this work we used...
Article
In this study, we investigate critical emotion-specific posture and movement features, which typically depended only on a small number of joints. The main goal is to minimal representative of emotional display by reducing the amount of joints involved in the movement. Beside to improve the computational efficiency, we can identify the important asp...
Article
This paper presents attitude determination using a designed observer for gyroless Low Earth Orbit spacecraft using two different estimation approaches which are Extended Kalman Filter (EKF) and Particle Filter (PF) algorithms. This designed system contributes as an alternative or backup system during rate data absence resulted from the unexpected f...
Article
Visually evoked potentials (VEP) are evoked responses of the brain corresponding to a specific visual stimulus. Ophthalmologists often refer their patients to VEP test if the latter suffers any vision abnormalities that cannot be diagnosed using conventional analysis. By investigating the VEP responses, medical experts can narrow down the possible...
Article
This paper presents the behaviour of empty and foam-filled aluminium alloy (AA6061-T6) tubes under dynamic axial loading. The influence of geometrical and various densities of fillers was investigated by employing a finite element code, LS-DYNA. The critical effective point for fillers of different densities is identified in a foam-filled tube base...
Conference Paper
This paper explain the analysis of internal air flow velocity of a bladeless vertical takeoff and landing (VTOL) Micro Aerial Vehicle (MAV) hemisphere body. In mechanical design, before produce a prototype model, several analyses should be done to ensure the product's effectiveness and efficiency. There are two types of analysis method can be...
Article
Full-text available
The simple needs of an ankle rehabilitation system are valid for medical evaluation, user-friendly, and perform efficiently at low cost. However, most of the current ankle rehabilitation systems face a lot of problems, such as inconvenient face-to-face therapy, manual evaluation by the physiotherapist, the limited number of physiotherapists, and th...
Article
Full-text available
This paper highlights on the development of a nurse following robot. A Nurse following robot is a personal robot to help the nurse to do their jobs every day. This robot will follow the nurse from bed to bed while carrying belongings such patients’ medical files, medicine and other equipment. The tracking system has been designed using a high speed...
Conference Paper
Full-text available
Over the past fifteen years, quantitative monitoring of human motor control and movement disorders has been an emerging field of research. Recent studies state the fact that Malaysia has been experiencing improved health, longer life expectancy, and low mortality as well as declining fertility like other developing countries. As the population grow...
Conference Paper
Full-text available
Retinal images are obtained using a fundus camera in order to evaluate many important diseases such as Diabetic Retinopathy and Glaucoma. Sometimes, the images appear as uniformly illuminated, have luminosity and contrast variability. This problem can be severely compromised the diagnostic process and the results, especially if automated computer-b...
Article
Full-text available
This study aims to investigate the response of AA6061-T6 conical tubes under oblique impact loading, for variations in filler density and tube material by using experimentally validated model. Good correlations between the numerical and experimental results were observed. The initial peak force and dynamic force increase from AA6061-T6 to carbon st...
Conference Paper
Full-text available
This paper discusses the circuit comparison of the electrocardiogram (ECG) heart rate detector for wearable biomedical devices. In this work, the QRS complex is used to calculate heart rate, representing the main component of the ECG signal. In order to achieve a high level of accuracy by the detector, the measured ECG signal must be free of noise....
Article
In the last two decades, non-invasive methods through acoustic analysis of voice signal have been proved to be excellent and reliable tool to diagnose vocal fold pathologies. This paper proposes a new feature vector based on the wavelet packet transform and singular value decomposition for the detection of vocal fold pathology. k-means clustering b...
Article
Full-text available
Nowadays, researchers are paying more attention to recognize the human emotions from various modalities such as facial features, physiological or biological signals and speech signals. In the last decade, a number of research works have been carried out on emotion recognition using speech signals. In this work, emotion recognition system was develo...
Article
Full-text available
Electrical bio-impedance measurement has great potential in many biomedical applications including vein graft surveillance. Studies have shown that thrombosis was the major cause of the vein graft failure. The meticulous skills of the surgeon and effective postoperative surveillance of vein graft remain the cornerstones of clinical success in the c...
Article
Wavelet theory is emerging as one of the prevalent tool in signal and image processing applications. However, the most suitable mother wavelet for these applications is still a relative question mark amongst researchers. Selection of best mother wavelet through parameterization leads to better findings for the analysis in comparison to random selec...