Preprints
Search for science and technology (81 results)
Assessment of global variations in the velocity–porosity relationship of marine sediments and rocks using the legacy data of scientific ocean drilling programs
Published: 2026-09-11
Subjects: Earth Sciences
The physical properties of sediments and rocks are routinely measured during scientific ocean drilling programs, as such data enable the recovered materials to be linked to geophysical observations and provide constraints on subseafloor lithology. However, lithological descriptions are not consistently linked to physical properties datasets for older drilling expeditions, thereby limiting global [...]
Linear geophysical inversion with seismic image-guided kriging
Published: 2026-09-07
Subjects: Geophysics and Seismology
Linear geophysical inversions, such as the mapping of surface gravity anomaly to subsurface density anomaly, are a cornerstone of geophysical practice. However, the high degree of ill-posedness of such problems makes interpretation of the resulting subsurface models challenging. I develop a methodology to combine surface potential field measurements, direct subsurface sampling through scout [...]
Hydroclimatic Regime Shifts and Compound Heat–Dry Events in Rajshahi Division, Bangladesh: Integrating Thermal Gradients, Change-Point Detection, and Heat-Driven Dryness Dynamics (1992–2022)
Published: 2026-08-08
Subjects: Climate, Environmental Indicators and Impact Assessment, Environmental Monitoring, Hydrology, Meteorology, Other Earth Sciences, Other Oceanography and Atmospheric Sciences and Meteorology, Statistical Models
Hydroclimatic variability and compound climate extremes are increasingly affecting monsoon-dominated regions of South Asia, particularly drought-prone northwestern Bangladesh. However, integrated assessments of thermal dynamics, atmospheric moisture, land–atmosphere coupling, and compound heat–dry events remain limited in the regional context. Therefore, this study investigated long-term [...]
Lead contamination in cassava-based food and tubers (Manihot esculenta Crantz) in French Guiana: evidence for soil-to-plant transfer as the primary source
Published: 2026-07-30
Subjects: Environmental Sciences
This study investigates lead (Pb) contamination in cassava in French Guiana, focusing on its sources, accumulation processes, and. Previous studies in the area have shown that cassava-based products could be a source of lead in diets, raising concern about human exposure. The results show that cassava tubers often contain lead concentrations and 72% of the analysed samples (n=81) exceed [...]
Machine-learning-based classification of shear-band particles in a discrete-element reverse-fault model
Published: 2026-07-25
Subjects: Earth Sciences, Engineering
Discrete element method (DEM) simulations provide time-resolved particle-scale information on particle motion, contact forces, rotation, and local deformation. However, these outputs are high-dimensional, making it difficult to directly interpret which particle-level descriptors characterize localized deformation. This study develops a machine-learning workflow for classifying shear-band [...]
Ground Motion Model Incorporating Azimuthal Dependence on Topographic Effects in Japan
Published: 2026-07-02
Subjects: Engineering
Conventional topographic terms in ground motion models (GMMs) typically characterize topographic effects using site-specific parameters such as relative elevation, curvature, or slope. This study demonstrates that topographic response is influenced by source-to-site geometry, specifically the incidence direction with respect to the slope aspect. Utilizing 15,189 records from 641 Kiban–Kyoshin [...]
Clay Characterization of Tiller Flotten Quick Clay
Published: 2026-07-02
Subjects: Earth Sciences, Geology, Mineral Physics, Other Earth Sciences, Soil Science
In this study, we investigate the mineralogical and physicochemical properties of the Tiller–Flotten quick clay formation in Trondheim, Norway. The objective is to enhance our understanding of particle interactions within this quick clay system, thereby contributing to the development of more environmentally friendly stabilization strategies. A comprehensive suite of analytical techniques was [...]
Socio-Demographic Predictors of Earthquake Preparedness Among University Students: Evidence from a Public University in Bangladesh
Published: 2026-06-21
Subjects: Geography
Bangladesh is exceptionally prone to recurring hydrological and meteorological disasters, which have traditionally dominated the national policy and disaster management discourse. Consequently, seismic risk remains heavily underemphasized, leaving major urban centers like Dhaka highly vulnerable to catastrophic human and structural losses from potential earthquakes. While structural mitigation [...]
Analyzing The Capabilities Of Frugal Digital Twins For Sustainable Smart City Infrastructure Development In Africa: An ESGS Perspective From Ghana.
Published: 2026-06-19
Subjects: Civil and Environmental Engineering
Digital twins, virtual replicas that mirror physical infrastructure through real-time data, have emerged as a pivotal technology for smart city development globally. However, their deployment in developing countries remains constrained by high costs, limited digital infrastructure, and insufficient local expertise. This paper analyses the capabilities of frugal digital twins as enablers of [...]
Metabolic retraction and virulence expansion in a tropical urban river microbiome under dry-season stress
Published: 2026-06-11
Subjects: Microbiology
Anthropogenic pollution and seasonal flow reduction concentrate untreated organic waste in tropical rivers, yet the coupled response of microbial metabolism and virulence gene repertoires remains poorly understood. We applied shotgun metagenomics to the Shitalakshya River (Bangladesh) from early (December 2024) to peak (February 2025) dry season. Dissolved oxygen fell to near-hypoxic levels, [...]
Fluid Flow Induced by Seismic Waves in Fractures
Published: 2026-05-29
Subjects: Physics
A theoretical and numerical analysis is presented on the squeezed film of an incompressible fluid between two parallel fracture walls induced by seismic waves at normal incidence. In the frame of small oscillations, a closed form of the fluid pressure changes along with the fracture, and the fluid velocity field distribution is proposed. The developed analytical solutions are valid for any [...]
Simulation-Based Sensitivity Analysis of Check-Dam Height Effects on Downstream Debris-Flow Depth for Structural Countermeasure Scenarios
Published: 2026-05-21
Subjects: Earth Sciences, Engineering, Other Engineering, Risk Analysis
Check dams can influence debris-flow propagation, but their effects may depend on location, height, and local topographic conditions. This study evaluates the sensitivity of downstream debris-flow depth to check-dam height scenarios using numerical simulations of a mountainous catchment in Atami, Japan. Six hypothetical check-dam locations were placed along the torrent, and 4,877 valid cases were [...]
DHAFGan: A Dense Hybrid Attention Fusion Generative Adversarial Network for Infrared and Visible Image Fusion
Published: 2026-03-22
Subjects: Computer Engineering
Aiming at the problems existing in the current infrared and visible light image fusion algorithms, such as insufficient perception of typical features, poor visual representation of the fusion results, and insufficient utilization of important secondary information, this paper proposes an infrared and visible light image fusion algorithm based on shallow-deep feature extraction and dual-channel [...]
Dynamic estuarine Chlorophyll-a estimation-based time series harmonized Landsat- Sentinel images
Published: 2025-12-12
Subjects: Environmental Studies
This research develops a vigorous approach to estimate Chlorophyll-a (Chl-a) concentration in the dynamic, optically complex waters (or Case 2 water including coastal waters, estuaries and inland water bodies) of Ganh Rai Bay, Vietnam by leveraging time series harmonized Landsat and Sentinel-2 (TM-HLS) imagery. One of the fundamental challenges while conducting this method to compute Chl-a signal [...]
Associations between Climate Change and Infectious Diseases: A Systematic Review
Published: 2025-12-04
Subjects: Public Health
Climate change is increasingly recognized as a major driver of infectious disease dynamics, influencing disease distribution, seasonality, and outbreak intensity. This systematic review synthesizes evidence on how climate variability affects infectious diseases and evaluates predictive modeling approaches. Following PRISMA guidelines, we searched Web of Science, PubMed, Embase, and Scopus for [...]