Search Results (162)

Hydraulic perturbations are among the earliest plant-wide consequences of drought, salinity and wounding, yet they are often treated as passive outcomes rather than as biologically interpreted inputs. This review distinguishes hydraulic state, hydraulic perturbation and hydraulic signal, and evaluates how organ-scale pressure and water-potential changes are converted into local membrane tension, wall strain, turgor and water-flux cues. We propose, as a testable model rather than an established mechanism, a distributed architecture comprising OSCA/TMEM63 and other mechanosensitive channels, cell-wall integrity pathways, aquaporin-mediated conductance control and vacuolar buffering. Evidence for the individual components is substantial, but evidence that they act together within a single physiological event is still limited. These layers are reciprocally coupled to Ca²⁺, ROS, electrical, hormonal and peptide networks. Hydraulic cues are fast, and they differ in amplitude, direction, rise time, duration, recovery and anatomical route, so they are not informationally inert. Specificity nevertheless appears to emerge from the integration of the hydraulic waveform with tissue state and coincident ionic, electrical and biochemical inputs rather than from any single variable. We compare drought, salinity and wounding; clarify the roles of roots, vasculature, bundle sheath, mesophyll and guard cells; and outline experiments that combine calibrated physical perturbations with live reporters, tissue-specific genetics and hydromechanical modeling. The key frontier is no longer to document that pressure changes occur. It is to identify the variables directly sensed, to separate instructive from permissive roles, and to test whether dynamic decoding traits improve crop resilience at acceptable carbon and growth cost. Full article

Radio frequency identification (RFID) tags are now included in the plastic wrap used to protect seed cotton formed into cylindrical or “round” modules on modern cotton harvesters. In this paper, the development of a new work tool system for handling round modules with articulated wheel loaders or telehandlers is described. The work tool system reads the module-specific identification number from the RFID tags in the wrap and associates the module’s weight, seed cotton moisture content, GPS location, cotton ownership, and load information with the module serial number. Finite element analysis of critical components indicated that the system was capable of processing modules weighing 3178 kg (7000 lb.) Module weight was determined on the loader using measurements of the hydraulic pressure in the lift arm circuit. Seed cotton moisture content was measured using a custom-designed resistance-based probe. To help reduce the potential for lint bale contamination from module wrap plastic, the work tool system was designed to rotate modules so that the wrap can be cut within the manufacturer-recommended cut zone before the wrap is removed at the gin. The total cost for the system configured for fully automated data collection and module rotation control was $28,909. Full article

Additive manufacturing (AM) has expanded the design space for actuator systems by enabling complex internal geometries, multimaterial architectures, functional gradients, embedded channels, and application-specific components that are difficult to realize using conventional fabrication alone. These capabilities are particularly relevant when actuator performance is governed by the coupling between material selection, printed architecture, stimulus response, and system-level integration. This review examines additively manufactured actuators and actuator components using a material-architecture-function-integration framework. The actuator classes considered include soft pneumatic and fluidic actuators, electroactive and piezoelectric polymer actuators, shape-memory and 4D-printed actuators, magnetic and magnetoactive actuators, and printed pneumatic, hydraulic, mechanical, and aerospace-grade actuator components. Representative applications are discussed across biomedical and rehabilitation systems, aerospace and deployable mechanisms, soft robotics, and industrial automation. Beyond summarizing printed actuator demonstrations, the review analyzes the integration barriers that determine whether AM actuators can transition from laboratory prototypes to functional systems. These barriers include material durability, leakage, fatigue, dielectric breakdown, filler dispersion, interfacial failure, dimensional variability, environmental sensitivity, auxiliary hardware requirements, sensing, control, and benchmarking. By organizing recent developments across actuator classes, application domains, and integration strategies, this review clarifies where AM provides a functional advantage over conventional fabrication and where further validation is required for reliable deployment. Full article

Wastewater treatment remains a major challenge in rural and peri-urban areas, where conventional centralized infrastructure is often unavailable or insufficient. In this context, Nature-Based Solutions (NBS) have emerged as cost-effective and energy-efficient alternatives for decentralized wastewater treatment. This review presents a comprehensive and multidimensional assessment of 15 NBS types, evaluating their technical performance, economic viability, environmental sustainability, and social dimensions. The analysis indicates that NBS can achieve pollutant removal efficiencies comparable to those of conventional treatment systems, particularly for organic matter and, in some cases, emerging contaminants. However, their performance is strongly influenced by system design and operational conditions. The main limitations of NBS include relatively low hydraulic and pollutant loading capacities, as well as substantial land requirements, ranging from 0.45 to 840 m²·PE⁻¹. These constraints limit their applicability in densely populated areas while making them particularly well suited for rural and low-density settings. From both economic and environmental perspectives, NBS offer significant advantages, including construction cost reductions of up to 66% and substantially lower energy consumption than conventional technologies. Nevertheless, their successful implementation depends not only on technical performance but also on social acceptance, stakeholder engagement, and the establishment of appropriate governance frameworks. Overall, NBS constitute a flexible and sustainable approach to wastewater treatment, whose effectiveness ultimately depends on site-specific conditions and the integration of complementary treatment components. Full article

Soil water models are increasingly required to support irrigation, drought assessment and sustainable water management, yet physical, artificial intelligence (AI)-based and hybrid approaches differ in process representation, data demand and transferability. This structured narrative review critically compared these approaches and used auxiliary publication-record mapping in Web of Science, Scopus and OpenAlex for 2015–2026; quantitative comparisons were based on the complete years 2015–2025. Aggregated annual database records increased from 21,795 to 38,899 for physical models (1.78-fold), from 203 to 4088 for AI-based models (20.14-fold), and from 61 to 669 for hybrid models (10.97-fold); because records overlapped across databases, these values indicate relative trends rather than unique publications. Physical models remained essential for mechanistic interpretation but were constrained by hydraulic parameterisation, boundary conditions, heterogeneity and scale mismatch. AI-based models enabled flexible multi-source prediction and remote-sensing integration but remained vulnerable to domain shift, weak extrapolation and limited process interpretability. Hybrid strategies provided specific benefits through parameter estimation, emulation, residual correction, data assimilation, physics-informed learning and differentiable coupling, while potentially inheriting uncertainty from both components. No model class was universally superior. Model selection should therefore be problem-oriented and supported by independent validation, uncertainty quantification, domain assessment and evaluation at root-zone and management-relevant decision thresholds. Full article

Hydraulic fracturing creates long-lasting contact between aqueous fracturing fluids and gas-bearing ultra-low permeability matrix rock, making fluid retention and dissolved-species penetration important for interpreting matrix–fracture mass exchange and post-fracturing flowback behavior. These processes are controlled by the coupled effects of capillary imbibition, fracture–matrix pressure assistance, and species diffusion, but their relative importance is difficult to distinguish through a concentration profile. This study develops a regime-adaptive pressure-assisted imbibition and species-transport framework for interpreting fracturing-fluid species movement from a hydraulic fracture into a gas-bearing porous matrix. The framework couples a pressure-assisted imbibition (PAI) model with a one-dimensional advection–diffusion equation (ADE), where the PAI-derived velocity provides the transient advective input for species transport. The same formulation continuously represents capillary-dominated, mixed pressure–capillary, and pressure-dominated behavior without switching governing equations. Three diagnostic limiting cases, Capillary-driven Advection, Pressure-driven Advection, and Diffusion-only, are introduced to compare reduced mechanism-specific responses with the Full PAI-ADE response without interpreting them as additive components of the full solution. At 100 days, the Full PAI-ADE concentration front in the Ultra-Low Matrix reached 31.9 cm at $C=0.10$, compared with 18.0 cm for Capillary-driven Advection, 9.2 cm for Pressure-driven Advection, and 21.7 cm for Diffusion-only, indicating a mixed diffusion–capillary response. For the High-Perm Matrix at 0.20 day, the Full PAI-ADE and Pressure-driven Advection fronts reached 211.6 and 210.9 cm, respectively, with a normalized profile error of 0.003, identifying a pressure-advection-dominated limiting behavior. A dimensionless mechanism-weight analysis based on the pressure–capillary ratio (${\mathsf{\Pi }}_{\mathrm{p}\mathrm{c}}$) and front-scale Péclet number (Pe) further summarizes these behaviors. The results demonstrate that the proposed framework provides a compact diagnostic tool for linking pressure–capillary driving, advective–diffusive tendency, and observable species-transport profiles in ultra-low permeability gas-reservoir applications. Full article

Pumped-storage hydropower requires pump-turbines to operate safely and efficiently under off-design conditions, where stall-induced unsteady flows can redistribute hydraulic losses and reduce operational stability. Unlike previous analyses focused mainly on spatial correlations, this study develops a spatiotemporal framework to clarify how hydraulic loss (HL) and vortex evolution (VE) co-vary under different stall states at the valley point of the pump-mode hump region in a low-specific-speed, ultra-high-head pump-turbine. Detached eddy simulations (DES) were performed for an original-runner scheme (ORI) and an optimized-runner scheme (OPT), with identical stationary components, boundary conditions, and numerical settings. The comparative cases cover four representative flow states: non-stall, fixed stall, rotating stall, and mixed stall. The local hydraulic-loss rate (LHLR) was decomposed into dissipation (DIS) and transport (TRANS) terms, and Liutex-based vorticity decomposition was used to distinguish shear- and rigid-rotation-related vortex quantities. Pearson correlation analysis was then applied in both space and time. The results show that DIS is consistently associated with shear enstrophy ${\Omega }_{\mathrm{S}}$, whereas the spatiotemporal correlation associated with TRANS and VE parameters exhibits stronger regional and stall-state dependence. These findings provide a quantitative basis for identifying loss-sensitive vortex features and support flow-control and runner-optimization strategies for improving pump-turbine efficiency and stability. Full article

To evaluate the structural safety of variable-speed pumped-storage units under extreme transient conditions, this paper focuses on a variable-speed unit at a specific pumped-storage power plant. Based on boundary conditions measured during on-site load shedding tests, a three-dimensional, unidirectional fluid–structure interaction numerical model was established, incorporating stationary components such as the volute, base ring, top cover, and bottom ring. A numerical prediction and analysis of the dynamic stresses and deformations of key components were conducted for a hazardous scenario in which all units shed load simultaneously and the volute pressure reached its peak. The results show that during the load shedding process, the maximum static stress in the stationary components was 79.5 MPa, and the maximum displacement was 0.066 mm; both occurred 46.01 s after load shedding at the junction between the guide vane outlet edge and the top cover, and this value is far below the material’s yield strength of 490 MPa. Preliminary numerical evaluations indicate that the unit’s stationary components meet strength design requirements under this extreme transient condition. Furthermore, the study revealed the time lag mechanism between the peak hydraulic load and the peak structural stress in the top cover. The numerical prediction method established in this study can provide technical support for the structural safety assessment of transient processes in variable-speed units. Full article

Currently, the study of individual parameters’ influence on the energy efficiency of hydraulic systems is one of the leading research directions for these types of drives. Determining the influence of individual components and system architectures on the energy efficiency parameter for exemplary objects and systems is a new body of knowledge that allows for the development of a basic and general method for determining the energy efficiency of hydrostatic systems. The method developed and presented in this article extends this knowledge, making it possible to determine the influence of liquid parameters and individual system components on the energy efficiencies achieved by hydrostatic systems. The method used for determining individual factors’ influence on achieved system energy efficiencies is utilitarian and allows for the determination of how changes in specific parameters affect the efficiency of operational systems based on the results of pressure and motion speed measurements. Experimental tests were conducted to determine total power variations and the quantitative relationship between volumetric and flow resistance losses as the oil temperature increased from 25 °C to 75 °C. Full article

Crack opening and reinforcement stress are two complementary indicators of the service state of reinforced concrete hydraulic structures, yet they are often predicted separately. This study develops a data-driven multi-task temporal fusion framework for joint 48 h ahead prediction of dam crack responses and rebar stress using multi-source monitoring data. The measured data comprise five crack-monitoring series, five rebar stress series, local temperature channels, reservoir water level, antecedent rainfall, and an auxiliary environmental signal over approximately four years. Target responses are aligned only at common measured timestamps; no synthetic target observations are introduced. A simplified engineering layout and plan-based crack–rebar distances are further used to examine whether an explicit spatial prior can strengthen the shared temporal representation without introducing synthetic target values. A residual multi-task temporal fusion network (MTTF-Net) is proposed with a shared Transformer encoder, attention pooling, task-specific decoders, and a response-continuity regularization term. The model is compared with persistence, Ridge regression, random forest, Extra Trees, XGBoost, and GRU baselines under a chronological train/validation/test split. For the independent test period, Ridge regression obtains the lowest overall RMSE (2.2968), whereas MTTF-Net provides the lowest crack RMSE (0.0141), the lowest overall MAE (1.0035), and the second-best overall RMSE (2.3813). Distance-informed ablation, denoted as MTTF-Net-S, remains close to MTTF-Net in macro-averaged $R^2$ but is not superior in the overall test metrics, indicating that the available horizontal distances are valuable engineering metadata but cannot replace richer three-dimensional structural connectivity. These results indicate that the monitoring data contain a strong linear autoregressive component, while multi-task temporal fusion improves nonlinear crack response prediction and remains competitive for stress forecasting. The source code is prepared as a public implementation package, whereas the measured monitoring dataset is subject to data owner restrictions. Full article

Cavitation in machine elements is often accompanied by surface degradation, material loss, and a reduction in functional performance and reliability. Despite extensive research on cavitation in hydraulic systems, its role in the behavior and durability of machine elements remains insufficiently addressed. This paper presents a critical review of cavitation and cavitation-induced erosion in machine elements, based on an analysis of relevant literature and standards. The study covers different types of components, including gears, plain and rolling bearings, and seals, with particular attention to the mechanisms of damage and the methods used for their investigation. The analysis shows that, although the fundamental mechanisms of cavitation are well understood and standardized testing methods are available, their application to machine elements is limited. Existing standards are not sufficiently adapted to specific components, while current numerical and experimental approaches rarely provide a direct link between cavitation phenomena and material degradation. The findings indicate the need for improved standardization, development of integrated modelling approaches, and a closer connection between cavitation mechanisms and the performance characteristics of machine elements. The presented analysis is relevant for design, reliability assessment, maintenance strategies, and the development of cavitation-resistant machine components in hydraulic and mechanical systems. Full article

Automating system-level nuclear thermal-hydraulic (T-H) model construction remains challenging because platform-specific API syntax, graph connectivity, parameter dependency ordering, and solver admissibility must be satisfied simultaneously. This study develops a closed-loop modeling framework on the SAFRI platform by combining supervised fine-tuning (SFT), a Plan-and-Act agent with retrieval-grounded parameter completion, and reinforcement learning based on group relative policy optimization (GRPO). The SFT stage uses a 6003-record domain corpus derived from expert-authored or expert-verified SAFRI modeling exemplars, while system-level generalization is evaluated on a held-out 50-case in-house evaluation set separated at the case-template level. At the component level, LoRA-adapted Qwen3-8B achieves 100% code accuracy, compared with 50% for zero-shot and 74% for one-shot prompting. At the system level, the SFT agent attains a 100% syntax success rate (SSR), 90% topology success rate (TSR), and 72.4% physical convergence rate (PCR), showing that local API correctness is insufficient for solver-valid model assembly. After GRPO training with schema, topology, physics, and sequence rewards, the full SAFRI-SFT-RL agent reaches a 100% SSR, 100% TSR, and 88.8% PCR on the in-house evaluation set, while an error self-healing loop resolves execution-time failures in an average of 2.3 corrective iterations. These results show that solver-grounded reinforcement learning is effective for closing the gap between syntactically correct script generation and physically convergent nuclear T-H model construction. Full article

Flood-induced scour and earthquake loading jointly govern the seismic performance of river-crossing bridges. Existing conditional fragility assessment frameworks based on static dependence structures do not fully capture the evolving correlations between component failure modes under cumulative hydraulic degradation. This study develops a probabilistic conditional fragility assessment framework for continuous bridges and quantifies the scour-dependent fragility at both the bearing and pier levels, along with the resulting system fragility under series and parallel idealisations. A three-dimensional nonlinear finite element model with scour-dependent soil–structure interaction is constructed in OpenSees, and incremental dynamic analysis is conducted using spectrally compatible ground motions. The results indicate that scour primarily affects the bearing fragility in the moderate to complete regimes, whereas it has a negligible influence on the bearing under minor damage conditions. Unlike bearings, the fragility of piers decreases systematically toward lower PGA values with increasing scour depth, accompanied by a distinct threshold-like sensitivity shift within a specific scour depth range. At the system level, the series model is influenced by the early exceedance probability of the bearings at low PGA, whereas the parallel model is primarily governed by the exceedance probability of the piers at high PGA. Overall, the results demonstrate that scour affects system reliability not only by altering the PGA of the structural components but also by modifying the exceedance probability gap between the bearing and pier. These findings suggest that linear degradation-based management approaches can lead to biases in risk assessment and provide a practical extension and scientific basis for developing bridge system assessments under multi-hazard conditions. Full article

Ni-based WC composite coatings are widely used to protect hydraulic components, yet the role of WC particle morphology in binder-phase strengthening remains unclear. In this study, two Ni40-based coatings containing 55 wt.% WC were laser-cladded on 0Cr13Ni5Mo steel under identical conditions using either rough spherical WC coating (RWC) or smooth spherical WC coating (SWC). Both coatings were mainly composed of γ-Ni, residual WC, W₂C, carbides, and borides. Although the rough WC particles showed about 38% lower intrinsic hardness than the smooth WC particles, the RWC exhibited a 25% higher binder-phase hardness and a 47% higher overall coating hardness. Accordingly, compared with the SWC, the RWC reduced the specific wear rate by about 33% under water-lubricated sliding. In slurry erosion, the RWC consistently showed lower erosion rates and less severe surface damage. The improved performance is attributed to the greater dissolution of rough WC during laser cladding, which strengthened the Ni-based binder and provided more stable support for the hard phases. These results demonstrate that tailoring WC particle morphology is an effective strategy for designing wear- and slurry erosion-resistant Ni-based laser-cladded coatings. Full article

Chinese Traditional Concrete (CTC), known as “San-he-tu,” has ensured the long-term durability of ancient coastal structures, yet its underlying material design logic remains insufficiently understood. This study investigates the Chongwu Ancient City Wall (Quanzhou, China), a Ming Dynasty granite fortification exposed to over 600 years of marine weathering, to elucidate the structure–property–function relationships of CTC across three functional layers: the horse-track surface, wall core backfill, and masonry bonding layer. A multi-technique analytical framework (XRF, XRD, TG, and SEM) was employed to characterize chemical composition, mineral phases, thermal behavior, and microstructure. Results reveal a deliberate “functional adaptability” material design. The surface layer adopts a rigid protective formulation with high quartz (76.9%) and CaO (17.06%), forming a dense, low-porosity matrix resistant to abrasion and weathering. The wall core exhibits a flexible filling strategy with high porosity (35.44%), enabling moisture dissipation and deformation accommodation. The bonding layer, enriched in kaolinite (~29.8%) and reactive Al–Fe components, promotes pozzolanic reactions that generate hydraulic gels, ensuring durable interfacial adhesion under humid coastal conditions. These findings demonstrate that ancient builders engineered zone-specific material compositions to meet distinct structural and environmental demands, forming a functionally graded system analogous to modern material design concepts. This study provides a scientific basis for adopting partitioned, differentiated restoration strategies in coastal heritage conservation. Full article