Physical Sciences and Mathematics Commons^™

Spatial Modeling Of Natural Disaster Risk By Integrating Hazard, Vulnerability, And Exposure Factors Using Geospatial Techniques : Evidence From Mueang Tak District, Thailand, Suphatphong Ruthamnong

Applied Environmental Research

This study presents a comprehensive multihazard risk assessment for Mueang Tak District, Thailand, that integrates hazard, vulnerability, and exposure (H-V-E) dimensions. By utilizing geographic information systems (GIS) and remote sensing, the analytic hierarchy process (AHP) was employed to prioritize critical risk factors. GIS analysis integrated multisource spatial data, including Landsat 9 and Sentinel-2 imagery, CHIRPS precipitation, and SRTM-derived topography, while AHP weights were established on the basis of expert judgment and socioeconomic indices such as the relative wealth index (RWI) and population statistics. The results delineate distinct spatial risk clusters: high landslide potential is concentrated in the steep terrain of …

Carbon Stock Assessment In Sonneratia Apetala Afforested Mangroves : A Case Study From Cox’S Bazar, Bangladesh, Mohammad Ismail, Sayed Abu Johany, Tanmoy Dey, Zakia Sultana Teasa, Trishna Das, Prabal Barua, Tonima Hossain, Sajib Ahmed

Applied Environmental Research

Sonneratia apetala is a key species for mangrove afforestation projects in Bangladesh and plays a crucial role in ecosystem restoration and carbon sequestration. The research on how the total carbon stock (TCS) varies across S. apetala plantations in Cox’s Bazar remains limited. Thus, in this study, the biomass and soil carbon stock were quantified across nine S. apetala afforested sites in Cox’s Bazar to assess spatial variation and influencing factors. The total biomass carbon (TBC) was calculated by summing the aboveground (AGBC) and belowground (BGBC) biomass carbon, while the soil organic carbon stock (SOCS) was determined from the 0–40 cm …

Seasonal Wastewater Monitoring And Quantitative Microbial Risk Assessment Of Escherichia Coli In A University Wastewater System, Pathum Thani, Central Thailand, Natsima Tokhun, Natagarn Tongphanpharn, Weerawat Ounsaneha, Montip Jankeaw, Wiriyabhorn Klomsungcharoen, Patsara Wongsudi, Yawanart Ngamnon, Cheerawit Rattanapan, Kwang Mo Yang

Applied Environmental Research

In this study, the physicochemical properties of wastewater were characterized, and a quantitative microbial risk assessment (QMRA) of E. coli was conducted in the wastewater treatment system of the Faculty of Science and Technology, Valaya Alongkorn Rajabhat University, under the Royal Patronage, Pathum Thani, Thailand (VRU-SciTech). This study was conducted because the current water-quality assessment does not include the QMRA or evaluate the occupa-tional and incidental public risk of infection. Over a one-year monitoring period, this study quantified wastewater generation (~6.09 L person-1 day-1; ~3.21 × 103 m3 year-1) and analyzed its physicochemical parameters and E. coli concentrations. High concentrations …

Performance And Mechanisms Of Activated Natural Coagulants For Efficient Microcystis Removal Via Coagulation–Flocculation In Thailand, Apiradee Sukmilin, Peangtawan Phonmat, Ratcha Chaichana

Applied Environmental Research

Thailand produces fruit peels and seeds rich in natural polymers, which can serve as eco-friendly coagulants to control algal blooms. In this study, banana peel (Musa spp.), orange peel (Citrus sinensis), basil seed (Ocimum basilicum) mucilage, and chia seed (Salvia hispanica) mucilage were used. These activated natural coagulants with aluminum were compared with nonactivated and commercial coagulants (ferric sulfate, ferrous sulfate, and polyaluminum chloride) for Microcystis removal. Phytochemical composition analysis, Fourier transform infrared (FTIR) spectroscopy, and oxidation–reduction potential (ORP) analysis were conducted. The results revealed that banana and orange peels contain phenolic compounds, …

Evaluation Of Soil Moisture Content, Ph, And Dominant Microorganisms In Crude Oil–Contaminated Soil Treated With Cow Dung, Indole-3-Acetic Acid (Iaa), And Simulated Microgravity, Amenze Ovenseri, Tawari-Fufeyin P.

Applied Environmental Research

Crude oil negatively affects soil physicochemical properties and microbial activity, thereby hindering plant growth and posing notable environmental and agricultural issues. The combined effects of cow dung, indole-3-acetic acid (IAA), and simulated microgravity on the recovery of soil degraded by crude oil were explored using Zea mays as the test plant. Soil was contaminated with crude oil at different concentrations (0%, 1%, 3%, and 5% v/w), with each concentration comprising eight treatments: cow dung, Zea mays seeds exposed to microgravity, and IAA alone or in combination. Changes in plant height, soil pH, soil moisture content, and soil microbial diversity were …

Evaluating Sediment Control Strategies Using Swat Based Bmp Assessment In A Tropical Highland Watershed, Northern Thailand, ฺBanchongsak Faksomboon, Wilailak Suanmali

Applied Environmental Research

Soil erosion remains a critical environmental challenge in the tropical highland watersheds of Southeast Asia, where steep terrain, intense monsoonal rainfall, and intensive land use interact to accelerate sediment generation and downstream degradation. This study aims to quantify spatial patterns of sediment yield and to systematically evaluate the effectiveness of individual and combined best management practices (BMPs) at both the watershed and subwatershed (SWW) scales using the Soil and Water Assessment Tool (SWAT) in a tropical highland watershed in northern Thailand. Baseline simulations reveal pronounced spatial heterogeneity in erosion severity, with substantial portions of the watershed exhibiting moderate to extreme …

Metal–Organic Frameworks : Opportunities And Challenges In Nutrient Recovery, Suchana Amnuaychaichana, Chi-Wang Li, Pongsak (Lek) Noophan, Sumeth Wongkiew

Applied Environmental Research

Nutrient recovery from waste streams is a critical strategy for promoting sustainable agriculture and mitigating environmental degradation. Essential nutrients commonly present in organic waste and wastewater, such as nitrogen and phosphorus, can be reclaimed and reintegrated into agricultural systems. Metal‒organic frameworks (MOFs), which are composed of metal clusters coordinated with organic ligands, have emerged as promising materials for adsorption and have the potential for nutrient recovery and pollutant removal because of their high porosity, large surface area, and tunable physicochemical properties. These attributes enable MOFs to serve in diverse applications, including heavy metal adsorption, organic pollutant degradation, and nutrient transformations. …

Exploring Consumers’ Intention And Behavior In The Circular Economy : Evidence From Vietnam, Tuan Hoang Nguyen, Vo Minh Thang Phan

Applied Environmental Research

This study aims to address the key gaps in understanding the factors influencing the intention–behavior relationship of consumers in the context of the circular economy (CE). Grounded in the theory of planned behavior (TPB), this research extends the framework by integrating social pressure, attitudes toward green consumption, and the availability of CE products as crucial components that shape intention and behavior. Data were collected from 603 Vietnamese consumers and analyzed using partial least squares structural equation modeling (PLS-SEM). The results confirm the core TPB constructs, with perceived behavioral control emerging as the most influential factor. Notably, attitude toward green consumption …

Sustainable Approach For The Removal Of Cu(Ii) From Aqueous Solutions Using Lotus Seedpod-Alginate Composite Biosorbents, Lan Tran-Nguyen, Hue Tran Nguyen-Le, Hong T Hi Anh Nguyen, Tran Nguyen-Phuong-Dung, Ly Kim-Phung, Huynh Quoc-Khanh, Nguyen Minh-Nhut, Phuong Lan Tran-Nguyen

Applied Environmental Research

Turning waste or agricultural byproducts into valuable products has recently become a concern of scientists. In this study, the facile and cost-effective synthesis of a biocomposite derived from lotus seedpod (LS) and alginate (AG) was further applied for Cu2+ ion uptake from aqueous solutions. SEM images revealed the layered structures of the composites, which were thin and irregularly stacked sheets of a complex 3D network. The abundant functional groups on the surface of the LS-based material and its negative zeta potential value of -37.50 mV also facilitated efficient Cu2+ removal. Adsorption results revealed a Cu2+ adsorption efficiency (AE) and experimental …

Tree Composition And Carbon Sequestration Potential Of A University Campus In Bangkok, Thailand, Chaiwat Boonpeng, Pawanrat Butrid Butrid, Marisa Pischom, Satatip Noikrad

Applied Environmental Research

Trees play important roles in atmospheric carbon dioxide (CO2) absorption and climate change mitigation. The objective of this study was to assess tree characteristics and carbon sequestration potential at Ramkhamhaeng University (Hua Mak Campus), Bangkok, Thailand. Tree attributes, including species composition, abundance, diameter at breast height (DBH), and tree height, were recorded. Tree biomass, carbon storage, and CO2 sequestration were estimated using appropriate allometric equations. A total of 2,149 trees were recorded in the study area, corresponding to a tree density of 45.8 trees ha-1. The tree community was dominated by the palm family (Arecaceae), while Terminalia ivorensis was the …

Development Of A Deep Neural Network Model To Predict Pm2.5 Concentrations Based On Key Factors Affecting Air Pollution In Bangkok, Natsuda Klinklan, Tanawut Poothong, Nuttiwut Areeratphitak, Viganda Varabuntoonvit

Applied Environmental Research

PM2.5 is a significant air pollution concern in Thailand, particularly in urban areas such as Bangkok, where the 24-hour average concentration frequently exceeds national ambient air quality standards during severe seasonal episodes. Road transportation is the primary source of PM2.5 in Bangkok, accounting for 73% of total emissions, according to the Pollution Control Department. In this study, a predictive modeling framework is developed to investigate the relationship between vehicle count and the mass concentration of PM2.5 from vehicular exhaust emissions. Convolutional neural networks (CNNs) and recurrent neural networks (RNNs) are employed for vehicle detection and counting, whereas a long short-term …

Weekly Spatiotemporal Dynamics Of Forest Fire Hotspots In Tak Province, Thailand : A Gis-Based Directional Analysis, Suphatphong Ruthamnong

Applied Environmental Research

Forest fires are recurrent dry-season hazards in northern and western Thailand, yet their short-term spatial dynamics remain insufficiently understood. In this study, weekly spatiotemporal dynamics of forest fire hotspots in Tak Province, Thailand, were examined using Visible Infrared Imaging Radiometer Suite (VIIRS) active-fire data and GIS-based directional analysis. Hotspots from five fire seasons (2021–2025) were grouped into 24 weekly intervals beginning on 1 December. The analysis integrated weekly hotspot counts, forest-type compositions, mean-center trajectories, standard deviational ellipses, temporal changes in topographic characteristics, and fishnet-based hotspot persistence mapping. The results revealed that fire activity was highly concentrated during the middle of …

Effects Of The Psb-To-Ow Ratio And Light Intensity On Biogas Composition During Phototrophic-Assisted Anaerobic Fermentation Of Organic Waste, Kridsana Jirasansawat, Sirilak Prasertkulsak, Nitiwist Teangthai

Applied Environmental Research

The integration of phototrophic processes into anaerobic fermentation offers a promising strategy for improving biogas quality; however, the combined effects of the photosynthetic bacteria-to-organic waste (PSB-to-OW) ratio and light intensity remain unclear. In this study, the photosynthetic bacteria (PSB)-assisted anaerobic fermentation of municipal organic waste under varying PSB-to-OW ratios and light intensities was evaluated. An optimal PSB-to-OW ratio of 1:2 resulted in significantly higher CH4 concentrations and lower CO2 and H2S concentrations than the other tested ratios did (p < 0.05). At this ratio, moderate illumination (2000 lx) resulted in the highest CH4 concentration (68.2 ± 0.3%), compared with 1000 lx (61.5 ± 0.4%) and 4000 lx (63.1 ± 0.5%). Under illumination, the CO2 and H2S concentrations were lower than those under dark conditions, indicating a more favorable biogas composition. Kinetic analysis indicated that CO2 and H2S exhibited apparent first-order behavior under illumination, with the highest rates occurring at 2000 lx (kH2S = 0.093 day-1; kCO2 = 0.059 day-1), suggesting light-dependent transformation processes. Metagenomic analysis revealed a microbial community dominated by sulfide-oxidizing (Chlorobium sp.), photoheterotrophic (Rhodopseudomonas sp.), and syntrophic bacteria, supporting coupled carbon conversion and sulfur transformation. Overall, optimization of the …

Investigating The Effects Of Pressure On Fe And Co Intercalated 2h-Tas2 Through First-Principle Calculations, Ronald E. Putnam Jr.

UNF Graduate Theses and Dissertations

Using first-principles methods, we investigate the effects of applied isotropic pressure on the electronic and magnetic properties of intercalated Fe1/3TaS2 and Co1/3TaS2. Fe1/3TaS2 has been shown to be a ferromagnet that undergoes structural and magnetic phase transitions under applied pressure. The magnetic phase transitions are observed to be linked to the structural shift, and a mixture of magnetic phase states is present between 3 GPa and 6 GPa. Co1/3TaS2 was found to be antiferromagnetic, as confirmed by experimental work. One- and two-unit-cell systems of Co1/3TaS2 are analyzed, both showing band splitting that disappears under pressure. The application of pressure forces …

Reclaiming Agency: Ai Hallucinations And Translingual Interrogations In The City Tech Writing Center,, Joseph Franklin, Anna Laura Falvey

Publications and Research

No abstract provided.

Flood-Regime Shifts Across The Lower Midwest, Usa: Identifying Patterns Through Flood Magnitude–Frequency Analysis And Clustering, Kaiser Mostafiz

Graduate Theses/Dissertations

Flood regimes describe how flood behavior changes in magnitude, recurrence, and occurrence through time. Changes in these flood characteristics can affect flood hazards, river systems, infrastructure, and floodplain management. This thesis examines flood-regime change across the Lower Midwest, focusing on Nebraska, Iowa, Kansas, and Missouri from 1961 to 2020. Records from 1,452 U.S. Geological Survey gaging stations were initially compiled, and 208 stations were retained after screening for record availability and analytical consistency. Flood-regime change was evaluated between two 30-year study periods: Period 1 (1961–1990) and Period 2 (1991–2020). The analysis combined Log-Pearson Type III flood-frequency analysis using L-moments in …

The Effects Of Financing Green And Brown Sectors: What Do Theories And Evidence Say?, Hao Liang, Maria Teresa Punzi

Research Collection Lee Kong Chian School Of Business

This paper critically examines the economic and welfare implications of financing green and brown sectors. Drawing on a comprehensive review of recent theoretical and empirical literature, we highlight that while conventional green finance—allocating capital toward environmentally friendly (“green”) sectors and away from carbon-intensive (“brown”) sectors—can promote decarbonization, it may also produce unintended externalities. In particular, it can inadvertently incentivize higher emissions from brown firms and contribute to economic disruption. Using a dynamic stochastic general equilibrium (DSGE) model, we demonstrate that lowering the cost of capital for green sectors leads to only modest reductions in emissions, whereas raising it for brown …

Fluid Agency In Ai Systems: A Case For Functional Equivalence In Copyright, Patent, And Tort, Anirban Mukherjee, Hannah H. Chang

Research Collection Lee Kong Chian School Of Business

Modern Artificial Intelligence (AI) systems exhibit fluid agency in multi-step workflows: lacking human-like consciousness or culpability, yet they display behavior that is (i) stochastic (probabilistic and path‑dependent), (ii) dynamic (co‑evolving with user interaction), and (iii) adaptive (able to reorient across contexts). These properties generate valuable outputs but collapse attribution, irreducibly entangling human and machine inputs. Doctrines that assume traceable provenance—authorship, inventorship, and liability—fracture under this unmappability, yielding ownership gaps and moral “crumple zones.”This Article argues that only functional equivalence stabilizes doctrine under unmappability: Where provenance is indeterminate, legal frameworks should treat human and AI contributions as equivalent for allocating rights …

Stormwater Best Management Practices, Kat Kelleher

UNH Cooperative Extension

No abstract provided.

Machine Learning For Predictive Energy And Emissions Modeling Of Vehicles And Power Grids In The United States, S M Tanvir Faysal Alam Chowdhoury

Dissertations

The environmental benefits of electric vehicle (EV) adoption depend on more than replacing internal combustion engine vehicles with electric powertrains. EV adoption reshapes electricity demand, interacts with regional generation mixes, and influences travel behavior and congestion, creating a coupled transportation-energy system in which vehicle and power-plant emissions must be evaluated together. This dissertation develops machine-learning frameworks for predicting energy consumption and emissions from vehicles and power grids under rising EV adoption. The first component forecasts grid emissions from EV charging. Using simulation data from NREL's Cambium database, a Prophet-based time-series framework predicts carbon dioxide, nitrous oxide, and methane emission rates …

Multivariate Quantile Autoregression-Mixed Data Sampling (Mvqar-Midas) Modeling Of Cost Of Living And Supply Chain Dynamics In Canada., Patrick Gbolonyo

Theses and Dissertations (Comprehensive)

In recent years, the rising cost of living as a result of persistent inflationary pressures, disruptions in the global supply chains, and changes in the macroeconomic landscape has become a critical topic of discussion. To address this, we move beyond a mean-based framework and employ a quantile regression approach. This allows the persistence of each series and the transmis- sion of shocks between the Consumer Price Index (CPI) (the total CPI which is a percentage change over the past 12 months), the Interest Rate (IR)(the target for the overnight rate), the New Housing Price Index (NHPI), and high-frequency supply chain …

Implementation Of A 3-Dimensional Hydrodynamic Numerical Model On A Large Northern Lake, Kirin Lorente

Theses and Dissertations (Comprehensive)

Climate change is impacting high latitude regions disproportionately more than those at a lower latitude. With polar lakes being highly sensitive to changes in the climate, shifts in lake ice dynamics and hydrodynamics are indicators of such changes in regional and global climates. These changes impact future seasons in a positive feedback loop, where changes in winter ice cover impact open water nutrients levels and lake thermal structure. This highlights the importance for long-term monitoring. Despite the abundance of lakes distributed across Northern Canada, there has been limited research conducted on these sentinels of climate change.

Specifically, Great Bear Lake …

Geovig And Purevig: Geometry-Aware Architectures For Efficient Computer Vision, Omar Ismail

Theses and Dissertations (Comprehensive)

Deploying deep learning models for medical image analysis on mobile devices requires a balance between inference latency, memory footprint, and delineating anatomical boundaries with high accuracy. While Convolutional Neural Networks (CNNs) and mobile Vision Transformers (ViTs) offer efficiency, they often struggle to model the irregular, non-local geometric structures inherent in biological tissues without incurring prohibitive computational costs. In this thesis, we introduce GeoViG (Geometric Vision Graph), an architecture that bridges the gap between efficient grid-based processing and explicit Geometric Deep Learning. GeoViG introduces a novel transition from high-resolution pixel grids to low-resolution dynamic graphs via a SpreadEdgePool operator, a geometry-aware …

Error-Driven Density Control For Compact Gaussian Splatting Under Sparse Supervision, Abdelrhman Elrawy

Theses and Dissertations (Comprehensive)

This thesis studies efficiency and stability challenges in Gaussian-splatting-based reconstruction under sparse supervision. In few-shot novel view synthesis, standard 3D Gaussian Splatting (3DGS) can overfit the limited training views and grow an unnecessarily large number of primitives due to limitations in its Adaptive Density Control (ADC) mechanism. This thesis introduces an error-driven reformulation of ADC that triggers densification using opacity gradients as a lightweight proxy for rendering error, and shows that such aggressive densification must be paired with delayed and conservative pruning to prevent destructive create--destroy cycles. When combined with depth-based geometric regularization, the resulting framework produces substantially more compact …

Assessing Dissolved Organic Matter Sources And Dynamics In Urban Stormwater: Implications For Greenhouse Gases, Harper W. Schmalz

Theses and Dissertations (Comprehensive)

Stormwater management ponds (SWMPs) are important aspects of land-use planning and increasingly recognized as active sites of biogeochemical processing that influence carbon cycling; however, little research has investigated the controls on dissolved organic and dissolved inorganic carbon (DOC and DIC) within these systems. This thesis examined the processing and transformations of dissolved carbon between three compartments to support the development of a greenhouse gas (GHG) box-model for urban stormwater ponds, including SWMP sediment, surface water, and vegetation. The objective of this thesis was to assess the biogeochemical processes that govern the rate and transformation of DOC and DIC between these …

Intelligent Electric Vehicle Routing For Goods Delivery Under Real-Time Traffic Conditions: A Comparative Framework For Modular Battery Swapping And Dynamic Wireless Charging, Ranjit Jakharabhai Odedra

Theses and Dissertations (Comprehensive)

Electric vehicles (EVs) are becoming central to sustainable and intelligent transportation systems, particularly in urban logistics, where reducing emissions, congestion, and operating inefficiencies is increasingly important. Despite their environmental advantages, the large-scale deployment of EVs in delivery operations remains constrained by limited driving range, time-consuming energy replenishment, and the difficulty of making routing decisions under dynamic traffic and load-dependent energy consumption. Addressing these challenges is essential for improving the practicality and reliability of EV-based freight transportation.

This thesis investigates optimization frameworks for EV routing in urban delivery systems by studying two complementary energy replenishment strategies: modular battery segment swapping and …

Impacts Of Burn Severity On The Hydro-Physical, Chemical And Thermal Properties Of Sub-Arctic Peat, Joshua B. Meyer Mr

Theses and Dissertations (Comprehensive)

Under current climate change, summer season in the boreal regions of Canada is becoming increasingly warmer and drier. This shift is driving increases in the frequency and intensity of naturally occurring wildfires and allowing access to areas not normally susceptible to fire such as wetlands. In peatland areas, these increasingly large fires can create complex burn scars, which contain a wide variety of different burn severities across different landcover types. This variety calls for a greater understanding of how varying fire intensity affects the hydro physical, chemical, and thermal characteristics of boreal peat. This study aims to deepen that understanding …

Investigation Of Mercury Bioaccessibility In Subsistence Fishes From The Canadian Subarctic, Kiran Mateo Sharma Mr

Theses and Dissertations (Comprehensive)

Fish consumption is the primary pathway for human exposure to methylmercury (MeHg), a global contaminant of concern known to cause adverse health effects. Fort Albany First Nation, a remote Indigenous community in northern Ontario that relies on fish for both subsistence and cultural practices, has expressed concern regarding the safety of local fish consumption. Community members and leaders have communicated several priorities for scientific research that are the foundation of this thesis. Specifically, consumers of wild-caught fish have asked how traditional cooking methods may affect mercury concentrations in fish, and how mercury concentrations in little-studied organs, such as liver and …

A Novel Federated Llm Framework For Distributed Traffic Modelling In Intelligent Transportation Systems, Seerat Kaur

Theses and Dissertations (Comprehensive)

Intelligent transportation systems (ITS) depend on accurate traffic prediction to support congestion management, infrastructure planning, and real-time operational decisions. Despite substantial progress in data-driven forecasting, several challenges continue to limit practical deployment: traffic data is distributed across independent regional authorities, making centralized aggregation infeasible, standard federated aggregation strategies ignore traffic-specific characteristics that meaningfully affect model quality, and existing models produce only numerical outputs without interpretable reasoning that urban planners can act upon. This thesis addresses these challenges through four contributions that collectively advance privacy-preserving, explainable, and scalable traffic forecasting.

The first contribution provides a systematic review of 129 peer-reviewed publications, …

Permafrost Microtopography And Active Layer Hydrology In The Western Canadian Arctic, Tobias L. Leonhard

Theses and Dissertations (Comprehensive)

The growing interest in Arctic regions will likely increase the use of nuclear energy in the Arctic. While this energy source has a high potential to improve economic opportunities in the Arctic, it also increases the release of radioactive material (radionuclides). Radionuclides are already found in the Arctic and are traced back to natural as well as anthropogenic sources. Water is one of the dominant transport vectors for solutes such as radionuclides or other contaminants. Therefore, improving our understanding of Arctic hydrology is important for assessing future environmental risks such as the release of radionuclides. Topographic and microtopographic features are …