Vol. 57 No. 1 (2025)

Dengue continues to pose a major public health challenge in Malaysia, with no definitive cure currently available. Although the Ministry of Health of Malaysia has implemented various measures to control outbreaks, the number of cases keeps rising and is likely to worsen due to the impacts of climate change. Hence, early detection and prediction of dengue outbreaks are vital for the implementation of risk mitigation measures. This study applied and assessed the performance of a coupled ARIMAX and SI-SIR model for forecasting dengue incidence in Penang, Malaysia. Data from 2014 to 2020,…

Weathering is often linked to economic mineral enrichment, including nickel, bauxite, and rare earth elements (REE). The exposed granitic rocks on Bintan Island, Riau Islands Province, belong to the Southeastern Asian Eastern Granite Province. This study examines the bauxitization process and REE distribution across weathered granite horizons in the Gunung Kijang area. Major oxides were analyzed using X-ray fluorescence, while trace and rare earth elements were determined by inductively coupled plasma–mass spectrometry. The trace element composition and metaluminous nature of the parent…

The periodic Fermi-Pasta-Ulam (FPU) chain is a Hamiltonian system modeling a one-dimensional chain of oscillators with a periodic boundary condition and nearest-neighbor interactions. While previous studies typically restricted the potential function in the Hamiltonian to cubic or quartic terms, this work considers a more general setting. Our aim is to demonstrate how Birkhoff-Gustavson normalization, combined with symplectic transformations, can be systematically applied to study the dynamics of Hamiltonian systems. We focus on the periodic FPU chain of four particles with alternating…

Atmospheric instability frequently influences the distribution of precipitation and is closely associated with atmospheric dynamics and thermodynamics. An increase in convective available potential energy (CAPE) has the potential to result in the development of convective clouds, which could contribute to extreme rainfall. This study used rainfall data from Asian Precipitation–Highly Resolved Observational Data Integration Towards Evaluation (APHRODITE) and CAPE data from the European Centre for Medium-Range Weather Forecasts. We defined extreme rainfall trends by applying the Expert Team on…