Polystyrene (PS) cutlery is a persistent single-use plastic waste with limited recycling value, requiring alternative valorization pathways. This study evaluated the hydrothermal liquefaction (HTL) of PS cutlery using a water–crude glycerol medium under
lower subcritical conditions, focusing on the production and quality of the dichloromethane (DCM)-soluble liquid product. The condition parameters were temperature, residence time, and water–crude glycerol ratio at 240–270 ºC, 60–120 min, 1:1–1:5 v/v, respectively. Feedstock characterization confirmed that the feedstock was predominantly PS, with aromatic hydrocarbon functional groups, high volatile matter, negligible ash, and a calorific value of 39.592 MJ kg-1. Results showed that temperature was the primary factor affecting liquid product yield, while residence time and solvent ratio acted in a condition-dependent
manner. The highest DCM-soluble liquid product yield of 50.11% was obtained at 270 ºC, 90 min, and 1:3 ratio. In contrast, the highest calorific value of 33.303 MJ kg-1 occurred at 240 ºC, 60 min, and 1:3 ratio, retaining about 84.1% of the feedstock energy content. Fourier transform infrared (FTIR) analysis indicated aromatic, aliphatic, and oxygenated functional groups, suggesting PS-derived liquid products with solvent-related secondary reaction products. Thus, the water–crude glycerol medium supported liquid product formation under moderated HTL conditions, but its effect was not a direct yield-enhancing
main effect. The findings also highlight the need for compound-level analysis and control runs to verify solvent-specific effects on product composition and recovery within the present lower-temperature experimental scope and limitations.

Underwater imagery suffers from various degradation effects due to the physical properties of water, including light absorption, scattering, and color distortion. These challenges significantly impact applications in marine research, underwater robotics, and ecological monitoring. While generative models like GANs and VAEs achieve state-of-the-art performance in underwater image enhancement, they suffer from issues like mode collapse and vanishing gradients. Diffusion models have shown superior performance in image generation and restoration tasks, but have been computationally expensive due to the iterative nature of the method, making them unsuitable for real-time underwater vision tasks. This paper presents ClearOcean, a novel Pyramid Diffusion model for efficient underwater image enhancement. This approach combines multi-scale denoising with spatial and channel-wise attention modules, achieving state-of-the-art performance while reducing computational requirements. A smaller model, ClearOcean-S, is also proposed to balance performance and inference speed. Both models were evaluated on the LSUI and UIEB datasets, demonstrating significant improvements in both image quality and processing speed compared to existing methods. Additionally, ClearOcean-S with ~90% less parameters than its larger counterpart achieved 3x speedup during inference, making it suitable for real-time inference requirements.

Floating communities in Agusan Marsh face persistent challenges in accessing reliable and safe water due to their geographic location, dependence on variable water sources, and exposure to seasonal flooding. This study assessed the potential and feasibility of rooftop rainwater harvesting (RRWH) systems in Barangay Sabang Adgawan, Barangay Maharlika, and Barangay Sabang Gibong using drone-based mapping, GIS analysis, household surveys, representative storage simulation, household-level costing, and a Modified Analytic Hierarchy Process (MAHP). Household-level RRWH potential was estimated based on roof catchment area, roof material, runoff coefficient, and mean annual rainfall, while feasibility was evaluated using physical, technical, economic, and social criteria. Results showed a mean annual rainfall of 3,461.71 mm, with mean annual RRWH potentials of 212.57 m³/year in Sabang Adgawan, 203.54 m³/year in Maharlika, and 175.30 m³/year in Sabang Gibong. Under the combined scenario, 60 of 122 households were classified under Higher Relative Feasibility, 49 under Moderate Relative Feasibility, and 13 under Lower Relative Feasibility. Social feasibility was the strongest enabling criterion, while economic feasibility was the main limiting factor. Findings indicate that RRWH is a promising but support-dependent supplementary water source for floating communities.

This dissertation developed and demonstrated a localized, stakeholder-sensitive Reactor Technology Assessment (RTA) framework for evaluating Small Modular Reactor (SMR) technologies and supporting evidence-based policy formulation for potential deployment in the Philippines. Although Executive Order No. 164 and related policy developments have introduced nuclear power as a potential component of the Philippine energy mix, the country still lacks a localized, stakeholder-sensitive, and industry-driven framework for evaluating reactor technologies. Existing tools, such as the International Atomic Energy Agency Reactor Technology Assessment (IAEA-RTA), provide a systematic and internationally recognized basis for reactor evaluation, but they do not fully capture the deployment conditions of a deregulated and industry-driven electricity market such as that of the Philippines.

To address this gap, the study developed a modified and stakeholder-sensitive adaptation of the IAEA-RTA framework for the Philippine power-sector context. The modified framework retained the original ten Key Elements of the IAEA Reactor Technology Assessment (IAEA-RTA) as its conceptual structure. For the Philippine case study, stakeholder-derived weighting assigned a value of 0.00% to Key Element 6 (Balance of Plant Design for Purposes Other than Electricity Production); consequently, the applied industry-driven assessment used nine weighted Key Elements while preserving the complete ten-Key-Element framework. Philippine energy policies, stakeholder statements, private-sector considerations, and deployment-related factors were incorporated into the assessment process. An Input-Process-Output structure and an industry-driven evaluation matrix were developed to improve the transparency, traceability, and applicability of the assessment workflow. More than 80 SMR technologies were initially reviewed using publicly available technical and institutional references. Based on deployment maturity, availability of verifiable technical information, construction or operational experience, and relevance to the Philippine setting, five SMR technologies were shortlisted for detailed assessment: ACP100, HTR-PM, KLT-40S, CAREM, and BREST-OD-300.

Results showed that the most emphasized assessment areas for Philippine SMR deployment were Economics and Financing (33.96%), followed by Site and Environment, Nuclear Safety, and Technology Readiness (11.32% each). Nuclear Island Design and Performance, Balance of Plant Design and Grid Integration, Safeguards and Protection, and Project Delivery received equal weights (7.55% each), while Fuel Cycle received the lowest weight (1.89%). Among the shortlisted technologies, ACP100 obtained the highest overall weighted score (3.99/5.00), followed by HTR-PM (3.86/5.00), KLT-40S (3.81/5.00), BREST-OD-300 (3.44/5.00), and CAREM (3.29/5.00). The relatively strong performance of ACP100 and HTR-PM was associated with deployment maturity, balanced performance across multiple assessment areas, and greater availability of publicly accessible technical information. However, no single SMR technology performed best across all Key Elements, indicating that reactor technology assessment should consider both technical performance and deployment context.

Sensitivity analysis further demonstrated that SMR rankings and comparative performance varied under different government and industry weighting scenarios, confirming that reactor technology assessment is influenced not only by reactor characteristics but also by stakeholder priorities, regulatory considerations, financing requirements, and deployment context. Policy synthesis further demonstrated that government policies primarily establish the regulatory and institutional foundation for nuclear energy development, whereas industry stakeholders emphasize economic viability, financing mechanisms, and investment readiness.

Overall, the study demonstrates that a localized, stakeholder-sensitive, and industry-driven adaptation of the IAEA Reactor Technology Assessment (RTA) framework can serve not only as a systematic tool for evaluating SMR technologies but also as an evidence-based decision-support framework for nuclear energy planning. By integrating technology assessment, stakeholder priorities, and policy synthesis, the developed framework supports transparent and context-specific decision-making for potential SMR deployment in the Philippines and may serve as a useful reference for other newcomer countries with similar electricity market structures and stakeholder environments.

The Philippine agricultural sector has experienced a continuing decline in its contribution to national GDP since 2016, highlighting the need for improved productivity through mechanization and technological innovation. Although four-wheel tractors can enhance farm output, the country remains dependent on imported units that are often not suited to local anthropometry, terrain, and operating conditions, resulting in ergonomic and safety risks such as musculoskeletal disorders and injury. Existing tractor standards largely emphasize mechanical and operational performance while giving limited attention to operator ergonomics. To address this gap, this study developed an ergonomic risk assessment framework integrating vibration, muscle workload, posture, and discomfort ratings to evaluate the Ronnie Baugh Tractor (RBT), a low-cost four-wheel tractor from Cuba being considered for localization and mass production in the Philippines. A total of 20 healthy male tractor drivers performed plowing operations using the RBT under field conditions. Vibration was measured at the base, seat, and engine using tri-axial accelerometers; muscle activation of the sternocleidomastoid, anterior deltoid, flexor carpi ulnaris, and gastrocnemius muscles was assessed through surface electromyography; posture was evaluated using Rapid Entire Body Assessment (REBA); and subjective discomfort was measured using the 10-point Wong-Baker FACES Pain Rating Scale. A cumulative link mixed model in R showed that subjective discomfort was significantly affected by muscle activation (β = 0.616, p < 0.001), vibration exposure (β = v 0.904, p < 0.001), and anatomical area, with the lower leg (β = 1.415, p < 0.001) and neck (β = 1.096, p = 0.001) exhibiting higher discomfort relative to the reference area. Posture also showed a significant nonlinear cubic effect (β = -0.539, p = 0.014), indicating complex changes in discomfort across operating positions. The lower leg had the strongest association with discomfort, suggesting that pedal placement, floor space, and awkward lower-limb posture were major concerns. In contrast, neck discomfort was linked to limited visibility and repeated head rotation during plowing. Results further indicate the need to reduce vibration by improving seat suspension, driveline, steering, and floor plate systems; enhance posture through adjustable seating, armrests, and steering alignment; and minimize muscle strain through an optimized control layout and seating ergonomics. Overall, the framework provides evidence-based design priorities for improving tractor safety, comfort, and suitability for Filipino farmers.