Search Results (1,796)

Reliable perception of small floating objects is critical for the management of aquatic environments and supports key applications, including the autonomous navigation of Unmanned Surface Vehicles (USVs), waterborne debris monitoring, and Search and Rescue (SAR) operations. However, accurate detection in dynamic water-surface environments remains a significant challenge, as targets are frequently obscured by high-frequency wave clutter, and feature distributions are destabilized by covariate shifts caused by illumination. To address these limitations, this study proposes YOLO11-MCN, a real-time detection framework that integrates two architectural components specifically designed for water-surface monitoring. The Multi-Scale Contextual Attention (MSCA) module distinguishes target signatures from background noise by aggregating contextual information across heterogeneous receptive fields, thereby suppressing false positives generated by waves. The Channel Normalization Attention Mechanism (CNAM) addresses illumination instability through feature statistic calibration based on Group Normalization, effectively mitigating covariate shifts induced by extreme lighting variations. Furthermore, these components are complemented by a high-resolution P2 detection head, which recovers the geometric details of small-scale targets typically lost during downsampling. Extensive experiments conducted on a dataset of 5812 images demonstrate that YOLO11-MCN achieves an mAP@0.5 of 92.7%, outperforming the YOLO11n baseline by 5.9 percentage points. Robustness evaluations confirm that MSCA and CNAM significantly reduce missed detections under severe wave clutter and backlighting conditions. With a recall of 90.5%, an inference speed of 94 FPS on desktop hardware, and a compact footprint of 3.89M parameters and 14.8 GFLOPs, the proposed framework offers a robust and efficient solution for intelligent water-surface surveillance systems within the single-class detection paradigm evaluated in this study, with strong potential for edge-device deployment following platform-specific optimization. Full article

Ensuring the sustainability of ageing water-storage infrastructure is an increasingly urgent challenge under climate-driven hydrological extremes. In the Republic of Korea, approximately 18,000 small and medium-sized agricultural reservoirs—many several decades old—pose escalating risks to downstream communities and threaten progress toward SDGs 6, 11, and 13. This study presents a 0.5 m airborne LiDAR-based, GPU-accelerated two-dimensional shallow-water simulation of a hypothetical breach of the Geumosan Reservoir, South Korea, using a MUSCL + HLL solver verified against the Ritter (1892) and Stoker (1957) analytical dam-break solutions. Two scenarios are compared: Run A with a uniform Manning coefficient (n = 0.035) and Run B with spatially variable roughness derived from the Korean Ministry of Environment land-cover map (mean n = 0.0711). Mass conservation is preserved to within 0.01% during the closed-domain phase. Spatially variable roughness expands the total inundated area by 8.5% (3.05 → 3.31 km²) while reducing the Extreme-hazard zone, defined by the DEFRA hazard rating HR = h(v + 0.5), by 24% (1.49 → 1.14 km²); arrival times in the downstream urban corridor are delayed by up to 30 min. Uniform Manning assumptions therefore systematically overestimate extreme-hazard extents while underestimating the broader shallow-inundation footprint—biases comparable in magnitude to breach-parameter uncertainty. By delivering reproducible, georeferenced hazard, arrival-time, and damage-class maps for emergency action planning, the proposed framework supports risk-informed and sustainable management of ageing reservoir infrastructure and community-level disaster resilience aligned with the Sendai Framework and SDGs 6, 11, and 13. Full article

In the context of increasing water scarcity, the new paradigm in efficient water management relies on the digitalisation of water infrastructure to optimise resource use. One of the key factors in addressing the new challenges facing urban water cycle companies is the shortage of qualified technical staff. This context highlights the new training needs of technical personnel required by companies in the urban water cycle sector due to the increasing digitalisation of tools and the new technological requirements of jobs which are not yet sufficiently reflected in the existing training offer. Companies express their dissatisfaction with how poorly existing training programs meet their current needs. Vocational training has a fundamental role to play in providing high-quality, technically up-to-date training that is aligned with the needs of water management companies. This mission involves the adoption of innovative teaching strategies and methods and the development of innovative teaching resources. This paper presents the design of a bench-scale plant specifically designed as a teaching resource at a Spanish vocational training centre that offers intermediate-level training in water networks and treatment plants and advanced-level training in water management. The plant, occupying a footprint of 4 × 5 m, simulates a drinking water distribution network, from the intake to the distribution network via a pumping station with two pumps (1 + 1) of 0.75 kW each that provide a flow range of 4–12 m³/h with a range of 22–10 m water column and a regulating reservoir of 1 m³ located above the water network. The plant is equipped with sensors that allow operational data to be monitored: pressures, flow rates, consumption and levels, enabling multiple operational scenarios to be simulated: leaks, sectorisation, pressure and flow management, etc. Its design has focused on facilitating the acquisition by students of the skills and learning outcomes required in the curricula of the different professional modules that make up the aforementioned studies, through learning based on multidisciplinary collaborative projects. Full article

This study presents a comprehensive assessment of high-temperature performance, economic viability, and environmental sustainability of alkali-activated slag paste (AASB) incorporating municipal solid waste incineration bottom ash (MSWI-BA). The research systematically evaluates the effects of MSWI-BA content (0–12%), alkali content (2–6% Na₂O equivalent), water glass modulus (Ms = 0.75–1.75), and activator type on key performance metrics, both resource recovery and carbon reduction goals. Results show that the optimized formulation (6% MSWI-BA, 4% Na₂O, Ms = 1.5) achieves superior high-temperature resilience, retaining 76% of its initial compressive strength after 800 °C exposure—a stark contrast to OPC, which undergoes near-complete strength loss. Economic analysis reveals that while MSWI-BA offers an 88% reduction in raw precursor cost, the optimized AASB incurs a modest 3.7% total material cost premium over OPC, which is offset by its long-term sustainability benefits. Furthermore, a life-cycle assessment demonstrates that AASB has a 66.95% lower carbon footprint than OPC. Full article

Intensive agricultural production contributes significantly to greenhouse gas (GHG) emissions, accounting for between 10 and 12% of global anthropogenic emissions, at a time when the agricultural sector is facing increasing pressure to adapt to ever-stricter environmental regulations. This study develops and applies a multi-objective Goal Programming model to identify the optimal mix of crops and management practices that simultaneously minimize the carbon footprint and maximize productivity, at the level of a 300-hectare (ha) model agricultural system in Romania. The life cycle assessment (LCA) methodology, in accordance with ISO 14040/14044 standards and Ecoinvent 3.8 emission factors, was applied to nine crops distributed across three soil types, within four management scenarios, over an annual planning horizon. The unit of measurement used is a ton of CO₂ equivalent per agricultural system. The results show that the optimized configuration achieves near-zero total carbon emissions (0.33 t CO₂eq for the entire farm), reduces synthetic nitrogen inputs to 35.7% of the limit set by the EU Nitrates Directive, and generates water savings of 48%. However, these environmental gains entail a 52.9% production trade-off relative to the maximum target of 3000 tons, highlighting a Pareto-optimal structural conflict between climate and food security objectives. The sensitivity analysis identifies the nitrogen emission factor and crop yield as the most influential parameters. The results confirm the technical feasibility of the European Green Deal targets through systematic mathematical optimization, while also demonstrating that achieving economic parity requires policy support of 110–165 EUR/ha/year. Full article

In 2023, Tropical Cyclone Freddy caused severe damage in southern Malawi, flooding much of the lowland area near Lake Chilwa and displacing many residents. This study evaluates long-term, region-specific mitigation strategies to lessen future risks, using a novel approach that combines drone and satellite data, building footprints, and 3D simulations to analyze how building elevation affects flood damage and assess Property-Level Flood Risk Adaptation measures. Results show a significant difference in ground elevation between affected and unaffected buildings, with damaged structures generally at lower levels. The 3D simulation confirmed a water-level rise of approximately 3.0 m caused by Freddy. Scenario analysis indicates that elevating buildings by 2.0, 2.5, and 3.0 m could reduce direct flood exposure and 64%, 76%, and 91% of damage, respectively. These insights can inform the development of targeted regional risk-mitigation strategies through Property-Level Flood Risk Adaptation in high-risk areas. Full article

Recycled aggregates (RAs) from construction and demolition waste (CDW) provide substantial circular-economy benefits, yet their elevated porosity, adhered mortar, and heterogeneity typically impair the mechanical performance and durability of recycled aggregate concrete (RAC). This PRISMA 2020-compliant systematic review synthesises 2180 records (2015–2026) to evaluate advanced strategies for enhancing RA quality prior to structural use. This paper critically compares removal-based treatments (mechanical, thermal, acid cleaning) with strengthening and densification approaches, including accelerated carbonation, pozzolanic and nano-silica coatings, polymer impregnation, microbial-induced calcium carbonate precipitation (MICP), and modified mixing methods such as triple-stage mixing (TSMA). Evidence shows that while all RA types (including recycled fine aggregate (RFA), recycled coarse aggregate (RCA), and their combination (RFCA)) can slightly reduce compressive strength and 30% replacement serves as a critical threshold, beyond this, strength loss accelerates, particularly in RCA and RFCA mixes. However, accelerated carbonation and TSMA consistently refine the interfacial transition zone, reduce water absorption by 17–30%, and recover 85–94% of natural aggregate concrete strength. Bio-deposition reduces water absorption by 13–21%, while acid/silica fume treatments improve late-age strength but carry environmental trade-offs. This review formulates a practice-oriented implementation framework for structural-grade RAC. Sustainability analyses indicate that carbonated RA can achieve net-positive CO₂ abatement when under low-carbon energy supply. A mechanistic schematic is presented to synthesise treatment-to-pore-structure/durability pathways across the four principal treatment routes, and a quantitative synthesis plot compares water absorption reductions across all treatment types using 13 data points drawn from included studies. A structured treatment comparison evaluates the energy intensity, industrial scalability, CO₂ footprint, and technology readiness level for each strategy. The remaining challenges include a lack of hybrid treatment studies, limited real-scale durability data, and insufficient mechanistic models linking treatment to pore structure evolution. This review recommends harmonised durability-based criteria and updates to standards (e.g., BS 8500, EN 12620) to support the scalable deployment of treated RA. Full article

Drying is a critical stage in the postharvest chain, shaping product stability, quality, and economic value. Freshly harvested beans contain high moisture, and inadequate drying can lead to microbial growth, physical deterioration, and loss of key sensory attributes. In recent decades, diverse technologies have been developed to enhance drying efficiency while preserving flavor, improving consistency, and reducing environmental impacts. This review adopts a systematic and comparative approach, synthesizing peer-reviewed literature on conventional practices, advanced solar dryers, mechanical systems, hybrid configurations, and emerging techniques such as microwave, infrared, and desiccant-assisted drying. Emphasis is placed on heat and mass transfer mechanisms, the influence of environmental and operational parameters, and the role of varietal and processing differences. Comparative analyses reveal trade-offs between energy consumption, drying kinetics, and impacts on physical and chemical quality. Sustainability aspects are also examined, including energy use, carbon footprint, water consumption, and scalability for smallholders. Finally, key research gaps are identified, particularly in multiscale modeling, real-time monitoring, and integration with renewable energy and smart control systems. The review highlights pathways for achieving greater consistency, lower environmental burdens, and stronger value chains in producing regions worldwide. Full article

AlGaN-based deep ultraviolet light-emitting diodes (DUV LEDs) have been widely deployed in water treatment, sterilization, and optical communication owing to their intrinsic merits of mercury-free operation, compact footprint, and fast turn-on capability. However, poor reliability and short operating lifetime, mainly caused by electrical degradation and poor heat dissipation, have severely limited their commercial applications. In this work, the degradation mechanism of 270 nm DUV LEDs was systematically studied via multi-condition accelerated aging tests. Results confirm that electrical stress is the dominant factor inducing device degradation, while thermal stress plays a secondary role. Electrical stress generates internal defects, increases leakage current and thermal resistance, enhances non-radiative recombination, and causes a sharp drop in light output power. Based on test data, the L70 lifetimes predicted by the inverse power law and the Arrhenius models are 5832 h and 5724 h, with relative errors of 8.59% and 10.28% compared with the measured 6380 h. This work provides reliable experimental support for the performance evaluation and lifetime prediction of DUV LEDs. Full article

Food security forms a vital foundation of national security. As core elements in food production, water and land resources play an irreplaceable role in ensuring the food supply. This study analyzes the water and land resources demand for food consumption by residents in nine Yellow River provinces from 2000 to 2023. We define the Baseline (S1), Dietary guideline (S2), Policy-oriented (S3), and Projection (S4) dietary structures and assess future resource gaps under these diets and propose optimized allocation. The results show that both urban and rural diets have shifted from predominantly plant-based to more diverse patterns. From 2000 to 2023, the cropland needed for plant-based foods decreased by 29.87%, while that for animal-source foods increased by 132.84%. The green water and blue water footprints of food consumption rose by 1.46 billion m³ and 17.73 billion m³, respectively. Considering potential land availability, by 2030, cropland requirements under dietary scenarios S2 and S3 can largely be met. The production water footprint gaps for S1, S2, S3, and S4 are 106.30, 29.73, 32.60, and 140.87 billion m³, respectively. S2 and S3 better support coordinated development of dietary needs and water–land resources, while S4 aligns more with rising demand for animal-based foods. Full article

The high environmental toll of terrestrial data centers described by their high land and water footprint has motivated new data center solutions. An important solution that has emerged from this motive is the space-based data center (SBDC). An SBDC is a space asset capable of processing the increased amount of data arising from space-based applications. Being in a non-geostationary earth orbit, it is important for important high-capacity hyper-scale space-based data centers to be capable of transmitting data to ground stations where valuable applications are hosted. This challenge necessitates addressing the maximum use of communication windows for non-geostationary space assets requiring further research attention. The research presented proposes an algorithm enabling the scheduling of power for optimal communication window functioning, to achieve high quality of service and make the best use of a communication window opportunity. This is achieved by increasing the power available to the SBDC communication subsystem. The evaluation shows that using the proposed approach enhances communication window utilization readiness and the communication window by 82.8% and 55.9% on average, respectively. Full article

In the Kingdom of Saudi Arabia (KSA) and other arid regions, higher education institutions account for a significant share of energy consumption and greenhouse gas (GHG) emissions. Improving the environmental performance of higher education institutions is important to achieving nationwide impact reduction. This study evaluates the water, energy, and carbon (WEC) footprint of higher education campuses in arid environments. Qassim University (QU), KSA, is a leading public institution of higher education and research in Buraydah City and was selected for this study. A comprehensive assessment based on the GHG Protocol was conducted for the period 2022–2025, covering Scope I, II, and III emissions. This study analyzed institutional data on water use, wastewater, electricity consumption, transportation, waste generation, and air travel. The results show that total water consumption increased from 354,747 m³ in 2022 to 547,268 m³ in 2025, with per capita use rising from 46.2 to 61.7 L/c/day. Net water demand, including irrigation, reached 877,456 m³ in 2025. The declining trend in energy consumption between 2022 and 2025 reflects significant (33%) energy savings with the use of sensors and the overall tendency towards sustainability. Correspondingly, Scope II emissions decreased significantly from 147.2 million kg CO₂/year to 99.1 million kg CO₂/year and were the dominant CO₂ contributor (60–75% of total emissions). In contrast, Scope III emissions from commuting staff and students increased, with transport-related emissions rising from 36.4 million kg CO₂/year in 2022 to 52.2 million kg CO₂/year in 2025. This study also evaluated current and potential CO₂ emission reduction scenarios targeting energy and transportation systems on the QU campus. The findings indicate that the deployment of a 5.1 MW solar energy system can generate approximately 8.6 million kWh annually, resulting in a reduction of around 4000 tCO₂ and contributing to nearly 43% of the 2030 emission reduction target. In addition, transportation-focused strategies—including modal shift, vehicle electrification, and hybrid learning approaches—demonstrate significant mitigation potential, with total reductions reaching up to 18,700 tCO₂ by 2030. Overall, this study contributes to the limited body of knowledge on WEC footprint assessments on university campuses in arid regions and provides a baseline for future sustainability planning. Full article

Biogas production through anaerobic digestion is increasingly recognised as a strategic renewable energy pathway capable of addressing South Africa’s energy insecurity, organic waste management challenges, and climate mitigation goals. However, the water-intensive nature of anaerobic digestion raises critical sustainability concerns in water-scarce regions. This systematic review critically examines the water footprint of biogas-based bioenergy systems, with a specific focus on South Africa’s water-stressed context, to understand how water availability, feedstock selection, digester configuration, and governance frameworks influence system viability and scalability. This study adopts a systematic literature review (SLR) approach guided by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) methodology; peer-reviewed literature published between 2010 and 2025 was retrieved from Scopus and Web of Science and synthesised through descriptive analysis and qualitative meta-synthesis. The review integrates blue, green, and greywater footprint concepts to assess water use across diverse biogas pathways, including livestock manure, agricultural residues, food waste, wastewater sludge, and aquatic biomass. Findings indicate that wet digestion systems, dominant in South Africa, are highly sensitive to freshwater availability, particularly where slurry dilution relies on blue water. In contrast, wastewater-integrated, semi-wet, and co-digestion systems substantially reduce freshwater demand while enhancing methane yields and process stability. The reuse of greywater, industrial effluents, and digestate emerges as a key strategy for lowering water footprints and strengthening circular water–energy linkages. Despite strong technical potential, the adoption of water-efficient anaerobic digestion systems remains constrained by fragmented governance, infrastructure deficits, and limited empirical data on dry and low-water digestion technologies. The review concludes that embedding water footprint considerations into bioenergy planning, policy, and system design is essential for the sustainable expansion of biogas in South Africa. Integrated water–energy–waste governance, coupled with targeted technological innovation, is critical to ensuring that biogas development enhances both energy security and water sustainability in water-scarce regions. Full article

Under high-intensity agricultural development, understanding the spatial allocation and scarcity pressure of agricultural water and land resources is critical for regional sustainability. Using water footprint and remote sensing data in Aksu, this study applies the spatial mismatch index, Gini coefficient, and scarcity indices to assess water–land matching and pressure dynamics and traces the migration of pressure center of gravity using the standard deviation ellipse model. The results show: (1) Water footprint and irrigated area increased over 2000–2020, with matching Gini coefficient fluctuating upward and severe mismatches in the northeast and southwest. (2) Resource scarcity indices fluctuated significantly; relative water scarcity peaked in 2015, and both pressure centers shifted eastward. (3) Economic factors are the primary drivers of water footprint and irrigated area changes, while water–land pressure correlates strongly with economic and production conditions. We conclude that Aksu’s water–land matching underwent a phased transition from relative balance to significant imbalance and then to gradual improvement, with 2015 as the critical turning point; the pressure centers migrated eastward (but at different distances); and economic factors dominate this evolution. These findings provide a scientific basis for differentiated waterland regulation in arid oasis agriculture. Full article

This investigation aims to experimentally evaluate the thermal performance of plasters reinforced with bio-based materials and to assess their contribution to sustainable construction and the reduction in the environmental footprint of building materials by simulating their impact on the thermal behavior of a building in different Moroccan climates using TRNSYS software. Three types of samples were investigated: pure plaster and two others strengthened by 4% of alfa fibers and 6% of coffee grounds. Each model was produced with the following different water-to-plaster ratios (W/P): 0.5, 0.6, and 0.7. The results demonstrated that the inclusion of aggregates and the increase in water content improved the thermal qualities of the composites. A combination of 4% alfa fibers and a W/P ratio of 0.7 significantly reduced thermal conductivity by 32.24%, decreased density by 26.82%, and lowered the decrement factor by 21.67%. Additionally, a composite containing 6% coffee grounds and a W/P ratio of 0.7 demonstrated a reduction in thermal amplitude by 15.61% and decreases in both thermal conductivity and density by 26.05% and 22.23%, respectively. Dynamic simulation indicated that these designs reduced greenhouse gas emissions and energy loads. However, energy gains using optimal configurations were considerable and similar in the following locations: Agadir (16.3%), Tangier (14%), Meknes (13.5%), Ifrane (13.42%), Marrakech (13.6%), and Er-rachidia (12.5%). Full article