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Abstract The classification of Alzheimer's disease (AD) using deep learning models is hindered by the limited availability of data. Medical image datasets are scarce due to stringent regulations on patient privacy, preventing their widespread use in research. Moreover, although open-access databases such as the Open Access Series of Imaging Studies (OASIS) are available publicly for providing medical image data for research, they often suffer from imbalanced classes. Thus, to address the issue of insufficient data, this study proposes the integration of a generative adversarial network (GAN) that can achieve comparable accuracy with a reduced data requirement. GANs are unsupervised deep learning networks commonly used for data augmentation that generate high-quality synthetic data to overcome data scarcity. Experimental data from the OASIS database are used in this research to train the GAN model in generating synthetic MRI data before being included in a pretrained convolutional neural network (CNN) model for multistage AD classification. As a result, this study has demonstrated that a multistage AD classification accuracy above 80% can be achieved even with a reduced dataset. The exceptional performance of GANs positions them as a solution for overcoming the challenge of insufficient data in AD classification.

Amphibian spherical robots are an appealing and practical alternative that can move around on different surfaces and function in aquatic environments. Spherical robots boast remarkable mobility and robustness, enabling them to navigate and perform exploration and reconnaissance tasks even in challenging or harsh environments. This paper explores assessing the terrestrial travel capabilities of a proposed amphibian spherical robot. A rapid Prototyping machine (RPM) was used to print the prototype’s main shell, yoke, and circuit holders. One main circuit was built on the yoke, while the other was positioned in the bottom shell. The driving principle used the barycentre offset notion, in which a pendulum mass is used to vary the location of the mass to generate a motion. Additional mass is added to the pendulum to determine the robot’s performance when mass is altered. The results reveal that the robot can travel on land with a maximum velocity of 40.75 degrees per second while carrying 600 grams of weight and a turning angle of 22.8 degrees. The robot can only move when the additional mass exceeds 400 grams. ABSTRAK: Robot sfera amfibia ialah satu alternatif menarik dan praktikal yang dapat bergerak di atas permukaan berbeza dan berfungsi dalam persekitaran akuatik. Robot sfera mempunyai mobiliti yang luar biasa dan tahan lasak. Ciri ini membolehkannya bergerak dan menjalankan tugas penerokaan dan peninjauan dalam persekitaran merbahaya atau buruk. Kajian ini adalah bagi menganalisis prestasi robot sfera amfibia ketika bergerak di darat. Mesin Pemprototaip Pantas (RPM) digunakan bagi mencetak badan utama prototaip, yok, dan pemegang litar. Satu litar utama dibina pada yok, manakala satu lagi diletakkan di bahagian bawah. Prinsip pemanduan adalah dengan menggunakan konsep penentuan kedudukan pusat jisim, di mana jisim pendulum digunakan bagi menentukan lokasi jisim sambil menghasilkan gerakan. Berat tambahan pada jisim pendulum ditambah bagi mendapatkan prestasi robot apabila jisim diubah. Dapatan kajian menunjukkan robot dapat bergerak atas darat dengan halaju maksimum 40.75 darjah sesaat sambil membawa 600 gram berat dengan sudut pusingan sebanyak 22.8 darjah. Robot hanya boleh bergerak apabila tambahan jisim melebihi 400 gram.

This article presents an adaptive logarithm-based sliding mode control (ALSMC) for an active suspension system to enhance ride comfort while maintaining the road holding and suspension space limits. The main objective of the control design is to devise a controller that does not require precise and accurate model parameters while ensuring resilience to model uncertainty and external disturbance. To achieve this objective, a natural logarithm sliding mode control (lnSMC) approach is adopted. Unlike the conventional sliding mode control that utilizes a linear sliding surface, the lnSMC is designed based on a natural logarithmic function, which creates the boundary layer of the controlled states. Thus, the selection of the controller parameter will be more practical as its value is dependent on the desired amplitude of the controlled state. This prevents trial and error when determining the controller parameter. In this study, the system’s dynamics are represented by a nonlinear quarter-car suspension model (e.g., nonlinear springs and piecewise dampers) with unknown model parameters. An adaptive law is incorporated to estimate all unknown model parameters, which is subsequently used for updating the control law. A simulation study is carried out to illustrate the effectiveness of the proposed control law under various types of disturbances, including sinusoidal road profile, bump road profile, and random road profile disturbance.

Unmanned aerial vehicles UAVs have been developed and refined for decades. Using an integrated software system, autonomous unmanned aerial vehicles (UAVs) perform missions automatically and return to a pre-programmed point. Malaysia has a lot of unoccupied airspace, yet autonomous UAV applications and research are still rare. In critical conditions, autonomous UAVs must deal with a variety of environmental and flight issues. This project involves a decentralized 3D collision avoidance system for an autonomous UAV. Ultrasonic, infrared, and laser rangefinders were chosen for the 3D collision avoidance system. The UAV's obstacle recognition and collision avoidance performance are also tested in four experiments. In various flight conditions, the 3D collision avoidance system can identify several material types and opacities by integrating selected rangefinders. Finally, the 3D collision avoidance system quickly reacts to obstacles in the X, Y, and Z axes. ABSTRAK: Kenderaan udara tanpa pemandu (UAV) telah dibangunkan dan diperhalusi selama beberapa dekad. Menggunakan sistem perisian bersepadu, kenderaan udara tanpa pemandu (UAV) autonomi melaksanakan misi secara automatik dan kembali ke titik pra-diprogramkan. Malaysia mempunyai banyak ruang udara yang tidak berpenghuni, namun aplikasi dan penyelidikan UAV autonomi masih jarang berlaku. Dalam keadaan kritikal, UAV autonomi mesti menangani pelbagai isu alam sekitar dan penerbangan. Projek ini melibatkan sistem pengelakan perlanggaran 3D terpencar untuk UAV autonomi. Pencari jarak ultrasonik, inframerah dan laser telah dipilih untuk sistem pengelakan perlanggaran 3D. Prestasi pengecaman halangan dan pengelakan perlanggaran UAV juga diuji dalam empat eksperimen. Dalam pelbagai keadaan penerbangan, sistem pengelakan perlanggaran 3D boleh mengenal pasti beberapa jenis bahan dan kelegapan dengan menyepadukan pencari jarak terpilih. Akhir sekali, sistem pengelakan perlanggaran 3D bertindak balas dengan cepat terhadap halangan dalam paksi X, Y dan Z.

The present study proposes a numerical method to solve the time-fractional Allen–Cahn equation. The Grunwald–Letnikov formula is employed for discretizing the time-fractional derivative, whereas the finite difference scheme is used for spatial approximation. Theoretical analysis indicates that the proposed method is stable in the discrete $ L_{2} $ L2-norm and the numerical results satisfy the energy dissipation property. Numerical simulations are conducted for validation of the proposed method. It has been observed that the solution profile approaches equilibrium for various fractional-order values in the range of $ (0,1) $ (0,1). Moreover, the fractional order values have a significant effect on the solution stabilization rate which is faster for larger values and slower for the smaller values. [ABSTRACT FROM AUTHOR]

The current work aims to study a new analytical solution method for a family of Kuramoto–Sivashinsky equation (KSE). For this purpose, we implement the q‐homotopy analysis method (q‐HAM), a method extensively used due to its easy implementation, fast convergence, and presence of convergence‐controlling parameters. This method does not require any transformation, linearization, or discretization. The applied method offers a well‐convergent series solution. Results are obtained for some fixed values of physically significant parameters involved in the mathematical model. The computed results are compared with the travelling wave solutions and are illustrated graphically and in tabulated form for absolute error estimation. The comparison reveals the q‐HAM provides better results than the existing methods. [ABSTRACT FROM AUTHOR]

Membrane application is widespread in water filtration to remove natural organic matter (NOM), especially humic acid. However, there is a significant concern in membrane filtration, which is fouling, which will cause a reduction in the membrane life span, a high energy requirement, and a loss in product quality. Therefore, the effect of a TiO2/PES mixed matrix membrane on different concentrations of TiO2 photocatalyst and different durations of UV irradiation was studied in removing humic acid to determine the anti-fouling and self-cleaning effects. The TiO2 photocatalyst and TiO2/PES mixed matrix membrane synthesised were characterised using attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy, X-ray powder diffraction (XRD), scanning electron microscope (SEM), contact angle, and porosity. The performances of TiO2/PES membranes of 0 wt.%, 1 wt.%, 3 wt.%, and 5 wt.% were evaluated via a cross-flow filtration system regarding anti-fouling and self-cleaning effects. After that, all the membranes were irradiated under UV for either 2, 10, or 20 min. A TiO2/PES mixed matrix membrane of 3 wt.% was proved to have the best anti-fouling and self-cleaning effect with improved hydrophilicity. The optimum duration for UV irradiation of the TiO2/PES mixed matrix membrane was 20 min. Furthermore, the fouling behaviour of mixed matrix membranes was fitted to the intermediate blocking model. Adding TiO2 photocatalyst into the PES membrane enhanced the anti-fouling and self-cleaning properties.

Study Design: A 2-year follow-up study. Purpose: To evaluate the effectiveness of modified halo-pelvic Ilizarov distraction assembly in the management of patients with severe kyphoscoliosis. Overview of Literature: Severe and rigid scoliosis curves are always a challenge for operating surgeons. Preoperative correction through halo-pelvic devices successfully minimizes the severity of the curve; however, cumbersome complications are also reported with its use. Modified assembly could be safe for these cases. Methods: Patients with severe kyphoscoliosis having coronal Cobb angle >90° were applied with modified halo-pelvic Ilizarov distraction assembly preoperatively. The modified assembly consisted of a pelvic component and halo ring, and distraction was given at the rate of 2–3 mm/day for 6–12 weeks. Complete clinical assessments along with pulmonary function tests were performed, and scoliosis series X-ray images were assessed for coronal and sagittal Cobb angle and other spinopelvic parameters before applying the assembly and during 2 years of follow-up. Results: Thirty-four patients (age, 9–27 years; male/female ratio of 18:16) were included. The coronal and sagittal Cobb angles were 116°±16.2° and 84°±28.3°, respectively. Correction rates obtained through modified halo-pelvic assembly were nearly 52% (p<0.001) in coronal and 40% (p<0.001) in sagittal Cobb angles, with improvement in height (p<0.001). Apical vertebral translation and coronal balance were also improved significantly (p<0.001). Further improvements in all the parameters were obtained after definitive surgery, with improvements in the forced expiratory volume in 1 second (p=0.002) and forced vital capacity (p=0.001). Conclusions: Our modified halo-pelvic Ilizarov distraction assembly can achieve good correction in severe spinal deformities without significant risk to neurology, has fewer complications, and promotes good patient compliance. [ABSTRACT FROM AUTHOR]

The integration of e-learning platforms in the higher education system has been around for a long time and is seen in line with the changes in Industrial Revolution 4.0 (IR4.0). Realizing this, Sultan Idris University of Education (UPSI), Malaysia has developed a Learning Management System (LMS) platform based on Technology Acceptance Model for its members to streamline learning and facilitating processes, namely MYGURU. The purpose of this study was to determine the applicability and attitude of the lecturers towards the used of MYGURU during the teaching, learning and facilitating process. Using a survey method, the study involved 734 and 248 lecturers who were selected using simple random sampling. The questionnaire was distributed by email in 2 months period. The results of this study found the mean score for MYGURU perceived usefulness and mean scores of lecturers' attitude to be at moderate level. The study of attitudes toward MYGURU used was modest, whereas the correlation test showed that there was a significant positive and moderate relationship between perceived usefulness and lecturers’ attitude. This study implies that developing a Learning Management System such as MYGURU requires continuous improvement in order to provide a better quality of higher education.

The focus of this study is the fabrication of innovative and sustainable ceramic-based geopolymer with improved low temperatures performances. Kaolin was mixed with liquid sodium silicate (Na2SiO3) and 12M of sodium hydroxide (NaOH) solution using alkali activator ratio of 0.24 and solid-to-liquid ratio of 1:1 to synthesize kaolin geopolymer. The effect of the sintering profile on the microstructure, pore evolution and flexural strength were investigated. The heating exposure aided consolidation and created a fairly uniform microstructure, resulting in a smooth surface texture. In comparison to the unheated geopolymer, 3D pore distribution showed a significant increase in the range size of ~30 µm with the appearance of isolated and intergranular pores. The flexural strength at 1200 °C with a heating rate of 5 °C/min and was increased by 146.4% to 85.4 MPa, as compared to the heating rate of 2 °C/min. The sintering process has an impact on the final microstructure formation thus improving the characteristic of geopolymer-based nepheline ceramic.

Titanium and its alloys are commonly preferred materials used for biomedical implants. However, these alloys have issues related to corrosion resistance as a result of the aggressive attack of human body fluids. Several researchers have attempted to produce a ceramic coating via physical vapour deposition (PVD). A PVD layer consists of pores, pinholes, and columnar growth that attack the substrate as an aggressive medium. The aim of this research is to evaluate the influence of ultrasonic vibration parameters on a TiN-coated biomedical Ti-13Zr-13Nb alloy. This study used TiN to formulate and coat disk-type samples in a fixed condition. Ultrasonic vibration at fixed frequencies was applied to TiN-coated samples for three sets of exposure times. The findings revealed that all TiN-coated samples exposed to ultrasonic vibration had improved corrosion resistance compared to untreated samples. Field emission scanning electron microscopy (FESEM) was employed to analyse sample’s microstructures. The top parameter (16 kHz and 11 min) yielded the most compact coating. Ultrasonic vibration’s hammering effect decreased the size of microchannels in the lining and reduced the rate of corrosion attack. The nanoindentation test showed that coated ultrasonic treated samples had a higher hardness/elasticity (H/E) ratio than untreated samples.

This study was conducted to identify the pathways by which bamboo sawdust (BSD) degrades into sugar (predominantly glucose) and the resultant glucose degrades into an organic acid during Mn leaching. Synthetic Mn ore (SMO) and low-grade Mn ore (LGMO) were leached with BSD as a reductant in sulfuric acid. Mn was determined by complexometric titration with ethylenediaminetetraacetic acid. Sugar derivatives and organic acids were determined by high-performance liquid chromatography. The samples were leach liquor treated in 4.0 M H2SO4 at 100 °C and sampled every 15 min until 360 min. BSD, which contained cellulose (56.11%) and hemicellulose (28.6%), and cellulose was degraded into glucose as the major sugar. The highest glucose concentration produced in the SMO and LGMO leaching system were 28.54 ppm and 19.45 ppm, respectively. The produced glucose reduced the Mn ores and was also degraded into organic acids, predominantly formic acid. The highest concentration of extracted Mn was 0.15 ppm for SMO and 0.06 ppm for LGMO. The highest formic acid concentration was less than 0.005 ppm for both ores. The results indicate that the formed glucose preferentially participated in Mn reduction rather than undergoing degradation. Thus, complete extraction of Mn could not be achieved because O2 competed with Mn to degrade glucose into an organic acid.

Allen Cahn (AC) equation is highly nonlinear due to the presence of cubic term and also very stiff; therefore, it is not easy to find its exact analytical solution in the closed form. In the present work, an approximate analytical solution of the AC equation has been investigated. Here, we used the variational iteration method (VIM) to find approximate analytical solution for AC equation. The obtained results are compared with the hyperbolic function solution and traveling wave solution. Results are also compared with the numerical solution obtained by using the finite difference method (FDM). Absolute error analysis tables are used to validate the series solution. A convergent series solution obtained by VIM is found to be in a good agreement with the analytical and numerical solutions. [ABSTRACT FROM AUTHOR]

Consensus problems in multi agent systems (MAS) are theoretical aspect convergence of doubly stochastic quadratic operators. This work has presented the dynamic classifications of extreme doubly stochastic quadratic operators (EDSQOs) on finite-dimensional simplex (FDS) based on the limit behaviour of the trajectories. The limit behaviour of the trajectories of EDSQOs, on FDS is either in state of convergence, or fixed or periodic. This paper aimed at examining the behaviour of these states. The paper modelled the states and proves theoretically the characteristics of each state. The results indicate that convergence operators converge to the centre $\left( {\frac{1}{m}} \right) $, and EDSQOs point are fixed with two or more points whereas periodic states exhibit sinusoidal behaviour. This work has contributed in understanding the limit of EDSQOs of the exterior initial points as fixed and periodic points developed spread attribute toward a fixed point.

Many different Artificial Neural Networks (ANN) models of flood have been developed for forecast updating. However, the model performance, and error prediction in which forecast outputs are adjusted directly based on models calibrated to the time series of differences between observed and forecast values, are very interesting and challenging task. This paper presents an improved lead time flood forecasting using Non-linear Auto Regressive Exogenous Neural Network (NARXNN), which shows better performance in term of forecast precision and produces minimum error compared to neural network method using Radial Basis Function (RBF) in examined 12-hour ahead of time. First, RBF forecasting model was employed to predict the flood water level of Kelantan River at Kuala Krai, Kelantan, Malaysia. The model is tested for 1-hour and 7-hour ahead of time water level at flood location. The same analysis has also been taken by NARXNN method. Then, a non-linear neural network model with exogenous input promoted with enhancing a forecast lead time to 12-hour. Both about the performance comparison has briefly been analyzed. The result verified the precision of error prediction of the presented flood forecasting model.

As a solution to the distributed multi-agent coordination, the problems of consensus or agreement have been widely explored and studied in the literature. This document provides an overview of consensus problems in multi-agent cooperative control with the goal of exposing the related literature and promote the research in this area. The document presents the theoretical results concerning the search for consensus in the involved topologies with information exchange that is invariant in time and change dynamically. Applications related to consensus protocols are studied for the cooperation of multi-agent systems. The presentation includes as well open problems and offers future research direction.

Nowadays, interfirm collaboration has become an increasingly popular strategy among many organizations in various industries, in order to remain competitive. Based on the contingency theory, this paper examines the moderating effect of interfirm collaboration on the relationship between Human Resource Management (HRM) practices and organizational performance. Interfirm collaboration refers to the collaboration strategies undertaken by R&D companies, with other companies in similar or diverse functional areas, including R&D, marketing, or manufacturing, to enhance performance. Using data from 64 R&D companies, the hierarchical regression analyses showed that only collaboration in R&D and functional collaboration in manufacturing significantly moderated the relationship between HRM practices and organizational performance. Overall, the results provided partial support in the domain of the contingency theory. These results, however, are limited by the small sample size, which might have produced non-significant findings. Therefore, the generalization should be taken cautiously. Future research with a larger sample size is needed to confirm the findings.