Search Results (4,040)

This research introduces a novel methodology that combines Building Information Modelling (BIM) and Economic Multi-Criteria Decision-Making (EMCDM) with Neural Networks to optimize hybrid renewable energy systems in small communities. Its core aim is to improve sustainability, technical performance, and financial vokiability through integrated modelling and decision-making. The approach is applied to a hydropower site, evaluating five Scenarios (IDs 1–5) under a Community and Industry model. Financial benchmarks include a 10% Minimum Required Return and a 7-year payback period. ID3—hydropower, solar, and wind—proves most effective, with ANPV of €10,905 (wet) and €4501 (dry), and ROI of 155%/64%. Its ROIA/MRA Index peaks at 539%, and Payback/N ratios remain within acceptable limits (55%/96%). LCOE stays stable in average conditions (0.042–0.046 €/kWh), rising in dry years (0.07–0.10 €/kWh). Profitability differences primarily stem from demand and curtailment, rather than production costs. The NARX neural network reliably models SS% values from renewable inputs with low error across scenarios. The integrated BIM–EMCDM framework ensures transparent, sustainable, and risk-balanced energy system decisions for long-term autonomy. Full article

Against the backdrop of multi-source water transfers and increasingly frequent extreme rainfall, short-term deterioration of reservoir inflow water quality has become a key risk to intake safety, treatment operations, and urban water-supply security. Traditional assessments based on static thresholds and annual or seasonal averages often fail to identify high-risk periods at the event scale. Using continuous online monitoring data from 2021 to 2024 for the inflow of Yuqiao Reservoir, Tianjin, China, this study developed a month-specific dynamic-threshold framework and green/yellow/red risk windows and integrated a reach-wise river–reservoir routing scheme; a two-box decay model; and a three-class risk trigger into a unified analytical framework for long-term background characterization, event propagation analysis, source-contribution interpretation, and early-warning evaluation. Results show that the permanganate index (COD_Mn) exhibits an overall stable-to-declining background with pronounced wet-season pulses, whereas total nitrogen (TN) and total phosphorus (TP) remain at moderate-to-high levels, with yellow/red risk windows clustering markedly in the wet season. In typical red and yellow events, nitrogen contributions from upstream control sections progressively accumulate toward the reservoir inlet along the river–reservoir cascade system, whereas in some events the residual contribution from unmonitored near-inlet inflows becomes dominant. The COD_Mn-based three-class trigger achieves an overall accuracy of approximately 71.5% and shows comparatively strong identification of yellow-level risk, while remaining conservative for red-level alarms. These findings indicate that coupling month-specific dynamic thresholds with event-scale routing-decay analysis and trigger-based classification can support inflow monitoring, intake-risk early warning, and coordinated operation of key upstream reaches and near-reservoir control zones in water-transfer–reservoir integrated systems. Full article

The long-term durability of adhesive anchors in aggressive environments is a critical concern for infrastructure safety, with steel corrosion being one of the most detrimental phenomena. While glass fiber-reinforced polymer (GFRP) anchors offer corrosion-resistant alternatives to steel anchors in harsh marine environments, the bond performance at the anchorage interface progressively deteriorates under wetting–drying (WD) cycles, which may compromise long-term anchorage integrity. However, the bond characteristics of GFRP anchors under WD exposure, particularly the development of predictive models, remain insufficiently understood. This paper presents an experimental investigation into the impact of WD cycles on the bond of GFRP adhesive anchors in concrete. Twenty-four specimens were tested under pull-out loads, considering two key variables: bonded length (40 mm and 80 mm, corresponding to 5 and 10 times the bar diameter) and number of WD cycles (0, 30, 60, and 90). Artificial seawater was prepared via ASTM D1141-98 to simulate marine exposure conditions. The results revealed that both bond strength and bond stiffness decreased significantly with increasing WD cycles, while the failure mode progressively shifted from the bar–adhesive interface to the adhesive–concrete interface. Based on the experimental data, a cycle-dependent bond strength model was developed to predict the bond degradation of the anchor–concrete interface after WD exposure. Requiring only the undegraded concrete strength, the proposed model effectively captures the coupled effects of WD cycles and bonded length on bond strength degradation, presenting a practical tool for the durability design and service life evaluation of GFRP anchorage systems in coastal and marine environments. Full article

In response to the technical bottleneck of the Venlo greenhouse’s inability to achieve year-round production due to the high temperature and humidity in the summer in South China, this study took an existing Venlo-type greenhouse in Guangzhou as the research object and constructed a three-dimensional computational fluid dynamics (CFD) model of the greenhouse by comprehensively considering key factors such as solar radiation, thermal radiation, and crop canopy resistance. After on-site experiments, it was verified that, except for the top area of the greenhouse, the temperature deviation between the model simulation values and the measured values was less than 2 °C, and the error rate was less than 5%, confirming the model’s accurate representation of the temperature field distribution within the greenhouse. Based on the characteristics of the temperature and humidity fields revealed by the CFD simulation (canopy temperature gradient K = 0.144 °C/m, maximum temperature difference between upper and lower layers 20 °C), an optimized scheme of “wet curtain fan + salt bath dehumidification equipment” for local cooling and dehumidification of the crop canopy was proposed, and a non-uniform air duct layout was designed according to the temperature gradient characteristics. Field experiments showed that after optimization, the daytime temperature of the crop canopy was mostly controlled within 30 °C, the relative humidity was stably maintained below 80%, and the maximum temperature difference along the length of the greenhouse was reduced from 7 °C to 2 °C, effectively solving the problem of poor cooling and dehumidification effects of the traditional system. This scheme enabled the stable operation and year-round production of Venlo-type greenhouses in South China during the summer, providing technical support and engineering reference for greenhouse environmental control in high-humidity areas. Full article

Nicotiana tabacum is a classic model for studying pollination on wet stigma. Reactive oxygen species (ROS) and nitric oxide (NO) production are closely related to stigma fertility and depend on the activity of redox enzymes. This study is devoted to the comparison of two tobacco lines differing in physiological parameters and reproductive success. Samsun is a tobacco variety that is widely used in research due to its low demands; however, the reproductive potential of the variety is quite low. Based on this variety, a new line was obtained, called “Fortune”; the plants are externally similar to the Samsun plants, but are more successful in reproduction. The total production of ROS + NO on the stigmas of the Fortune plants is lower than the Samsun plants, but their ROS production is higher, and the main decrease occurs due to NO. Superoxide dismutase activity differs between the two lines at all stages of stigma development except the fertile stage, while ascorbate peroxidase activity is higher in “Fortune” at all stages. Additional isoforms of ascorbate peroxidase are detected in developing stigmas of the Fortune variety. Presumably due to differences in redox metabolism, Fortune plants produce more seeds, their fruit are larger, and their leaves and flowers are also larger compared to the Samsun plants. In this study, we investigated both redox homeostasis parameters and plant productivity using tobacco as the model plant and suggested that there is a correlation between these groups of parameters, which may be important for breeding highly productive plants. Full article

East Africa is highly vulnerable to climate change due to limited adaptive capacity and strong reliance on rain-fed agriculture. Ethiopia, in particular, experiences recurrent socio-economic losses from droughts and floods. This study presents a national-scale assessment of observed (1981–2010) and projected (2041–2100) changes in extreme seasonal precipitation across Ethiopia using ten ETCCDIs. High-resolution Enhancing National Climate Services (ENACTS) observations and bias-corrected outputs from a selected ensemble of CMIP6 models under SSP2-4.5 and SSP5-8.5 scenarios are used to assess historically trends and future extreme precipitation, respectively. Historical trends show increases in extreme precipitation during the Kiremt (JJAS) season, particularly over the northwestern, western, and southwestern highlands; however, most of these increases are not statistically significant. In contrast, the Belg (FMAM) season exhibits widespread declines, which are also largely not statistically significant. Future projections suggest increases in total precipitation (PRCPTOT), heavy (R10) and very heavy rainfall days (R20), very wet days (R95p) and extremely wet days (R95p), and rainfall intensity (SDII) over northwestern, western, southwestern, and parts of northeastern Ethiopia during JJAS. During FMAM, PRCPTOT is projected to increase in the northern and northwestern regions, while decreases are expected in the northeastern and southeastern regions. The Awash and Tekeze basins emerge as key hotspots of change, indicating potential seasonal shifts and an increased likelihood of extreme weather in these regions. Despite inter-model uncertainty, the results highlight the need for flexible, uncertainty-informed adaptation strategies to enhance climate resilience in Ethiopia. Full article

Groundwater plays an indispensable role in daily life. However, with the continuous advancement of industrialization, more attention should be paid to the quality of groundwater and the associated potential health risks in areas surrounding industrial parks. In this study, groundwater samples collected in the city of the Tibetan Plateau during the wet season (WS) and dry season (DS) were analyzed using Piper diagrams, Gibbs diagrams, and correlation analysis. The results elucidated the hydrochemical characteristics, formation mechanisms, and controlling factors of groundwater in the area. Groundwater potability was assessed using the Entropy-weighted Water Quality Index (EWQI) method. In addition, the health risk assessment model was applied to evaluate potential risks for four population groups, with NO₃⁻ and F⁻ selected as representative groundwater pollutants. The findings revealed that groundwater in the study zone was typically moderately alkaline and characterized primarily as soft–fresh and hard–fresh. The groundwater in both seasons mainly exhibited HCO₃–Ca chemical facies. Water–rock interactions involving silicate and carbonate minerals were identified as key processes controlling the hydrochemical composition in both seasons. EWQI results showed that groundwater quality for drinking purposes was excellent in the seasons. Sensitivity analysis further showed that Cl− exerted the greatest influence on the drinking water quality evaluation in both seasons. Health risk assessments revealed that the risks posed by NO₃⁻ and F⁻ to infants, children, adult females, and adult males remained within acceptable limits (with max values of 0.63, 0.39, 0.28, and 0.33 in the WS, and 0.59, 0.36, 0.26, and 0.31 in the DS, respectively). However, infants exhibited greater susceptibility than the other groups across seasons, with a risk index approximately twice that of adults. Overall, the findings contribute valuable insights for the sustainable management and planning of groundwater resources in the study zone. Future research could refine the risk assessment model with localized data and explore mitigation strategies for elevated risks in specific seasons or regions. Full article

The carbonate massifs of the southern Italian Apennines host extensive karst aquifers, which represent the principal drinking water resources. This study focuses on the Dragone Plain polje, a vast closed karst depression located in the main recharge sector of the Terminio–Tuoro carbonate massif. The polje drains a ~55 km² endorheic catchment and may be flooded during the cold and wet season, forming a temporary lake. We employed continuous hydroclimatic time series (rainfall, groundwater level, spring discharge, and river level) together with sparse Sentinel-2 true color satellite images for the period 2020–2024 to analyze the flooding process in the polje and its hydraulic connection with the saturated zone of the karst aquifer. Results indicate that lake formation depends on the balance among soil moisture, rainfall intensity, and runoff development, which were modeled on a daily scale. Daily recharge was also estimated and compared with groundwater level time series from the deep karst aquifer. The modeling was integrated with cross-correlation analysis of the time series, providing insights into the propagation of precipitation pulses through the hydrogeological system. This case study represents an important example for understanding the relationship between karst polje hydrological functioning and climate in a Mediterranean area. Full article

Quantifying moisture transport through building envelope materials is vital for durability, energy efficiency, and healthy indoor environments. Water vapour diffusion resistivity (µ-value) is a key parameter for hygrothermal modelling, moisture control, and mould risk assessment. Globally, data for solid wood species are scarce, and in Australia—despite the rising use of plantation-grown timber—critical hygrothermal properties remain undocumented. To close this gap, this study experimentally evaluated Eucalyptus nitens, a plantation-grown hardwood widely used in Australian construction. Solid-wood specimens prepared from industry-sourced boards were tested at 23 °C and 50% RH using both the wet-cup and dry-cup methods of the gravimetric technique. For wet-cup tests, µ-values ranged from 24 to 33; for dry-cup tests, µ-values ranged from 179 to 273, showing clear variability linked to differences in relative humidity. Experimental issues included surface cupping, sealing integrity, and extended equilibration time during dry-cup testing. These findings provide the first empirical µ-value dataset for E. Nitens under moderate-humidity conditions, delivering essential input parameters for hygrothermal models and supporting moisture-safe, energy-efficient design strategies for the broader construction sector. Full article

Wet path delay (WPD), required to correct sea-level measurements from satellite altimetry, is routinely estimated using observations from onboard microwave radiometers (MWR). However, when MWR retrievals are invalid or absent, WPD is generally obtained from atmospheric models, unless observations from external sources, such as scanning imaging radiometers, are available in spatial and temporal proximity to the altimeter measurements. These external observations, however, provide total column water vapor (TCWV) rather than WPD, and a reliable TCWV-to-WPD conversion is necessary. Current state-of-the-art conversions use TCWV only or TCWV and near-surface air temperature. The first approach is particularly relevant when external sources provide TCWV only. In this context, this paper presents, first, a comprehensive intercomparison of the methods available in the literature and, second, an improved TCWV-to-WPD conversion. The results show that one of the existing functions underestimates WPD by up to 1.6 cm in regions of high water vapor content, while another provides accurate WPD values only under specific atmospheric conditions. This study proposes an updated methodology that yields accurate WPD across the entire TCWV range, highlighting the importance of a reliable TCWV-to-WPD conversion for accurate sea-level estimation when valid MWR observations are unavailable. Full article

Wetlands are the largest natural source of atmospheric methane (CH₄), and their emissions are projected to increase during the 21st century in response to climate change. However, how extreme climate events such as extreme heat, extreme precipitation, and their compound occurrences modulate future wetland methane emissions, remains poorly constrained. Here, we quantify the impacts of extreme temperature, precipitation, and compound hot–wet events on global wetland methane emissions (eCH₄) using simulations from the dynamic global vegetation model LPJ-wsl driven by four CMIP5 climate models under a high-emission scenario (RCP8.5) for the period 2006–2099. Our results show that extreme heat events intensify and become substantially more frequent, with global occurrence increasing by more than 303% by the end of the century. Correspondingly, their contribution to global wetland methane emissions rises from ~26–28% in 2006 to ~73–83% by 2099, making extreme heat the dominant driver of future eCH₄ increases. Extreme precipitation events exhibit relatively modest changes in frequency and mixed intensity. In contrast, compound hot–wet events, despite their low baseline frequency, increase by more than 600% and are associated with disproportionately strong methane responses, driven by the combined effects of elevated temperatures and enhanced anaerobic conditions. Across all event types, tropical wetlands account for 75–90% of global methane emissions, while contributions from mid-latitudes increase modestly and high-latitude contributions remain comparatively small. These findings highlight the emerging importance of climate extremes—particularly extreme heat and compound hot–wet events—in shaping future wetland methane emissions. Explicit consideration of extreme-event dynamics is therefore essential for improving projections of methane–climate feedback under continued global warming. Full article

Snow density plays a crucial role in water resource estimation, runoff forecasting, and early warning of natural disasters such as avalanches and blizzards. This study uses optical satellite multispectral reflectance data to retrieve snow density, providing a novel perspective for snow density retrieval research. Supported by auxiliary data including CanSWE in situ measurements, Sentinel-2 satellite data, and ERA5-Land reanalysis data, this study constructs a hybrid model (Snow_ACMix) that integrates the strengths of the multi-head attention mechanism and convolutional neural networks, realizing direct snow density retrieval from multispectral satellite reflectance data for the first time. This research was primarily conducted in Canada and Alaska. For the Canadian region, the model achieves a mean absolute error (MAE) of 0.034 g/cm³, a root mean square error (RMSE) of 0.051 g/cm³, and a coefficient of determination (R²) of 0.547. For the Alaska region, the model yields an MAE of 0.020 g/cm³, an RMSE of 0.029 g/cm³, and an R² of 0.803. Feature and module ablation experiments are carried out, and one-shot transfer learning is adopted to perform snow density retrieval in the Alaska region. The spatial transfer prediction results show an MAE of 0.027 g/cm³, an RMSE of 0.038 g/cm³, and an R² of 0.747, which verify the model’s excellent spatial generalization ability and superior performance in data-scarce regions. The advantages and limitations of the Snow_ACMix model are investigated through comparative validation across different land cover types, regions, time periods, and against ERA5 data. The Snow_ACMix model achieves favorable retrieval performance in mountainous areas, and its practical application capability is verified by snow density retrieval in the Silver Star Mountain region. However, the model still has limitations: it is vulnerable to the effects of wet snow, resulting in large fluctuations in retrieval results in wet snow regions. Full article

Friction pairs in wet clutches operate under complex conditions, which can cause surface damage and reduce overall clutch reliability. Surface texturing is an established technique for improving the tribological performance of such mechanical interfaces. Inspired by the wet adhesion properties of tree frog foot pads, a bionic regular hexagonal micro-texture was designed on the mating steel plate. A three-dimensional transient computational fluid dynamics (CFD) numerical methodology was developed and rigorously verified via pin-on-disc friction experiments. Subsequently, this verified numerical framework was extrapolated to establish disc-on-disc CFD models. The results demonstrated that the bionic hexagonal micro-texture altered flow field characteristics, increasing the local maximum flow velocity by 7.9% compared to untextured surfaces. Furthermore, the micro-textured grooves expanded the effective area for convective heat transfer and facilitated local fluid exchange, reducing the maximum average bulk temperature by 20.5% and the maximum radial temperature by 20.7%. Adjusting the structural parameters of these micro-textures further regulated the interfacial flow and temperature fields; notably, deeper grooves induced vortices at land region edges, accelerating flow velocity and decreasing the overall radial temperature gradient. This study provides a theoretical reference for enhancing the thermo-hydrodynamic performance of wet clutch friction pairs. Full article

Layered sodium transition-metal oxides are promising cathode materials for sodium-ion batteries due to their high theoretical capacity; however, their practical application is often limited by sluggish Na⁺ diffusion kinetics and structural instability during cycling. P2/O3 phase coexistence has been proposed as an effective strategy to balance capacity and stability, yet it is typically achieved through precise Na-content tuning or complex synthesis conditions, which restrict compositional flexibility. Herein, we demonstrate a phase-engineering approach that induces stable P2/O3 phase coexistence without adjusting the overall Na stoichiometry by controlling the dopant incorporation pathway. Using Na_0.8(Ni_0.25Fe_0.33Mn_0.33Cu_0.07)O₂ (NaNFMC) as a model system, Mg doping via a wet chemical route enables homogeneous dopant distribution, which triggers local stacking rearrangement and the formation of prismatic Na⁺ diffusion channels characteristic of the P2 phase. In contrast, dry-doped samples with identical Mg content retain a predominantly O3-type structure, highlighting the decisive role of dopant incorporation in governing phase evolution. As a result of the phase-engineered P2/O3 coexisting framework, the Mg wet-doped cathode exhibits enhanced initial reversibility, superior rate capability, and improved long-term cycling stability compared to pristine and dry-doped counterparts. Voltage-resolved dQ/dV and cyclic voltammetry analyses reveal stabilized redox behavior with reduced polarization, while electrochemical impedance spectroscopy confirms suppressed impedance growth and improved Na⁺ transport kinetics after cycling. This study establishes that phase engineering through controlled dopant incorporation provides an effective alternative to conventional Na-content tuning strategies for layered sodium cathodes. The findings offer a scalable and versatile design principle for optimizing the electrochemical performance and structural durability of next-generation sodium-ion battery cathode materials. Full article

Dryland farming systems in South Dakota face rainfall variability and rising water demand, which can reduce crop productivity and threaten long-term soil health. We combined field experiments across three dryland sites in South Dakota (Roscoe, Selby, Fort Pierre) with continuous soil moisture monitoring (0–15, 15–30, 30–45 cm) and HYDRUS-1D modeling to evaluate cover crops and soil amendments (biochar, manure) on water retention. During the active cover crop growth period, plots with cover crops consistently exhibited lower soil water content than plots without cover crops, likely due to increased transpiration. Plots with no cover crop (NCC) retained more water than cover crop (CC) plots (Roscoe: 26.27% vs. 24.16% at 0–15 cm). During the primary crop growing season, biochar consistently increased soil moisture (θ) compared with manure and unamended plots. Following a 43-day dry spell (1 July–13 August 2024), soil moisture declined by approximately 0.096 m³ m⁻³ in the biochar plots, compared with 0.125 m³ m⁻³ under manure and 0.216 m³ m⁻³ in the unamended control, exhibiting differences in water retention capacity among treatments. HYDRUS inverse modeling reproduced observed soil moisture dynamics (R² ~ 0.91) and demonstrated higher water content under biochar. Scenario analysis using representative wet (2008) and dry (2012) years showed the cover crop + biochar combination maintained the highest average water content. Results support integrating biochar with cover cropping to buffer drought and improve soil water availability in dryland farming. Full article