Search Results (1,648)

Intercropping systems are beneficial for resource utilization; however, the spatial proximity of companion species leads to competition for shared resources, particularly light. A walnut–potato intercropping model was established to understand the photosynthetic and physiological mechanisms underlying yield and marketability responses. Three intercropping treatments were established based on the number of potato ridges between walnut tree rows: B1 (three ridges), B2 (five ridges), and B3 (seven ridges). All intercropping and monoculture (CK) plots used an identical double-row planting pattern per ridge. Results showed that ridge density induced significant physiological changes and yield impacts. Compared to CK, B3 significantly reduced soluble protein content, net photosynthesis (Pn), and antioxidant enzyme activities (SOD, CAT), while B1 and B2 showed intermediate, non-significant reductions. Peroxidase (POD) activity increased progressively with ridge number (B3 > B2 > B1 > CK), indicating dose-dependent shade stress. Intercellular CO₂ concentration (Ci) was significantly elevated under all intercropping treatments, suggesting a predominantly non-stomatal, biochemical limitation on photosynthesis rather than water stress. Yield was highest in CK, followed by B1 and B2—which were statistically comparable to CK—while B3 yielded the least due to severe shading. Marketability declined sharply in B3, with fewer than half of tubers reaching commercial grade. Multivariate analysis showed distinct clustering of yield-associated variables (Pn, protein, marketability) separate from shade-stress indicators (POD, Ci) across treatments. These findings provide practical and scientific evidence to optimize walnut–potato intercropping configurations under the arid conditions. Full article

The increasing adoption of Plant Factories with Artificial Lighting (PFAL) has intensified the reliance on Internet of Things (IoT) technologies for real-time monitoring and control of environmental and operational variables. While IoT-based architectures enable precise resource management and productivity optimization, PFAL systems remain highly vulnerable to component failures, sensor malfunctions, communication faults, and energy disruptions, which may compromise crop integrity and system reliability. These risks are particularly critical in low-cost and small-scale PFAL implementations, where maintenance capacity and redundancy are often limited. Existing IoT-based PFAL monitoring systems typically address either hardware or software redundancy in isolation and rarely incorporate a dedicated maintenance-oriented fault detection layer validated under realistic multi-failure scenarios. This study addresses these challenges by proposing a low-cost redundant system architecture for PFAL applications that simultaneously integrates (1) hardware redundancy through multi-sensor configurations; (2) analytical redundancy based on residual generation and threshold-based fault isolation; and (3) a maintenance-oriented fault detection layer capable of identifying abnormal internal device conditions. Experimental validation was conducted using four hardware configurations—Arduino Nano with Ethernet, ESP32, STM32 with Wi-Fi, and STM32 with Ethernet—evaluated across five fault scenarios: dust accumulation, water exposure, high temperature, fire detection, and physical impact. The STM32 with Ethernet configuration consistently achieved the fastest fault detection response times across all tested scenarios. Future work will focus on the integration of machine learning-based predictive maintenance algorithms, multi-node PFAL network deployments, and long-term field validation. Full article

This study investigates the influence of organic matter properties in surface waters on the efficiency of single- and two-stage coagulation processes in drinking water treatment plants. The research was conducted at three treatment plants supplied by different surface water sources over a 15-month monitoring period. The analyzed parameters included total and dissolved organic carbon (TOC and DOC), biodegradable dissolved organic carbon (BDOC), water color, UV absorbance, zeta potential, and molecular weight distribution of organic substances. The results showed that coagulation efficiency depends strongly on both the concentration and the molecular characteristics of organic matter. The highest removal efficiency was observed for high-molecular-weight fractions (>2.0 kDa), mainly humic substances, whereas low-molecular-weight compounds were removed less effectively. The study also demonstrated that surrogate spectrophotometric parameters, particularly UV₂₅₄ absorbance and color at 410 nm, can be used to monitor and optimize the coagulation process. Given the increasing frequency of extreme climate events and rapid shifts in raw water quality, optimizing single- and two-stage coagulation configurations has become an urgent operational necessity. This work provides a novel direct linkage between simple spectrophotometric indexes and precise chromatographic molecular ranges, delivering an immediate, high-impact predictive tool for real-time dosage optimization in water treatment engineering. Full article

Students and workers spend much of their day in school and office environments, where poor indoor air quality (IAQ) can negatively affect health and comfort. Indoor vegetation is increasingly proposed as a low-cost nature-based solution (NBS) to improve IAQ. This study evaluated the effects of phytoremediation on IAQ and indoor microclimate in schools across different regions and educational levels, as well as in office environments, under real-world conditions. Several C₃ plants (e.g., Chamaedorea, Schefflera, Ficus, Epipremnum, Yucca, and Spathiphyllum) were used, with crassulacean acid metabolism (CAM) plants (Sansevieria) included in selected settings. Temperature, relative humidity, CO₂, PM_2.5, and PM₁₀ were continuously monitored using intercalibrated low-cost sensors in absence and presence of vegetation. A comparable plant configuration was implemented in offices to assess its effects on volatile organic compounds (VOC). Indoor greenery reduced particulate matter, especially PM10 (18–20%), and improved microclimatic conditions by lowering air temperature (1–2 °C) and increasing relative humidity (6–15%). However, CO₂ reductions were limited and context-dependent. In the tested office environments, plant introduction was associated with reduced total VOC concentrations (25–50%). Overall, our results further support that indoor vegetation constitutes a robust, cost-effective nature-based solution (NBS) capable of complementing conventional ventilation systems in both school and office environments. Full article

As plant-based diets catalyze a global shift toward sustainable consumption, Chinese plant-based food firms are experiencing rapid growth and seeking to expand their international footprint. This study investigates the mechanisms underlying the internationalization performance of these firms by integrating the Technology–Organization–Environment (TOE) framework with a configurational perspective. We operationalize nine antecedents across three dimensions: the technological dimension (technological maturity, supply chain resilience, and digital transformation), the organizational dimension (food safety certification intensity, strategic partnership intensity, and talent acquisition intensity), and the environmental dimension (market adaptability, compliance and risk management, and product line breadth). Utilizing fuzzy-set qualitative comparative analysis (fsQCA) on a sample of N = 29 publicly listed Chinese plant-based firms, this research identifies three distinct equifinal pathways to superior internationalization performance. The first is the Collaboration-Compliance configuration (Organization–Environment-driven), which is primarily characterized by the synergy between strategic partnerships and regulatory risk management. The second is the Supply Chain-Compliance-Product Diversification configuration (Technology-Environment-driven), where international success is predicated on the interplay among supply chain resilience, institutional compliance, and product variety. The third is the Full-Factor Synergy configuration (Technology-Organization-Environment jointly driven), which emphasizes a holistic coupling of technological innovation, organizational coordination, and external institutional adaptation. By uncovering these complex causal mechanisms, this study moves beyond traditional linear analysis to reveal how diverse capability configurations can lead to equivalent internationalization outcomes. The findings provide actionable strategic guidance for firms navigating the global plant-based market and offer theoretical insights for policy frameworks supporting sustainable dietary transitions. Full article

Postharvest seed cleaning is critical for ensuring high-quality rice seeds suitable for storage and planting. Traditional cleaning systems, which are often limited to one or two sieves, are insufficient for removing all impurities, resulting in reduced seed purity and potential germination issues. This study was designed to enhance the rice seed cleaning system by integrating a high-efficiency blower with a triple-sieving mechanism. The system utilized three sieves with progressively smaller mesh sizes to systematically separate contaminants such as dust, broken grains, husks, and other foreign particles. A controlled airflow from the blower distributes rice seeds uniformly across the sieves, optimizing separation while minimizing mechanical damage. Compared to existing conventional systems, the proposed design demonstrated significantly improved cleaning performance, resulting in higher seed purity levels and overall enhanced seed quality. The triple-sieve configuration, coupled with precise airflow control, led to more effective impurity removal and uniform seed handling. The improved seed-cleaning system offers several agronomic benefits, including reduced postharvest losses, increased seed germination rates, and improved crop establishment. By producing cleaner, higher-quality seeds, this system has the potential to support more efficient and productive rice cultivation. Full article

Healthcare facilities are among the most energy-intensive public infrastructures due to their continuous operations, complex systems, and critical service requirements. In this context, Energy Performance Contracts (EPCs) have gained increasing attention as a strategic tool for enhancing energy efficiency and sustainability in healthcare facilities. This paper investigates the potential and implementation of EPCs in the hospital sector, with a particular focus on their integration within Public–Private Partnership (PPP) frameworks. The study addresses that gap through a cross-case analysis of fourteen hospital EPC projects implemented in Italy, the United Kingdom, the Nordic countries and Central-Eastern Europe, mapping their technical scope against a three-family taxonomy (envelope, plant systems, regulation and monitoring) and benchmarking their energy and economic performance. All figures reported derive from project documentation and contractual monitoring records. The results show that envelope-led configurations deliver the deepest reductions in primary and final energy consumption (up to 50% on the baseline), while plant-side measures, and trigeneration in particular, generate the largest absolute CO₂ savings (from approximately 500 to 17,000 tCO₂eq/yr); lighting, and building management systems (BMS) retrofits, although ubiquitous, account for a 20–25% band when deployed in isolation. The findings reframe EPCs as a configurable contract for decarbonization in healthcare environments and offer practitioners a reading grid for scoping future hospital retrofits under this framework. Full article

One of the main technological challenges in plasma wakefield acceleration (PWFA) research and development is achieving stable and reproducible acceleration. In particular, for PWFA schemes based on particle-driven plasma wave excitation, beam stability and timing jitter are increasingly critical. In these configurations, magnetic or radio-frequency (RF) compression schemes are often used, and the beam time-of-arrival jitter at the end of the linear accelerator can be strongly correlated with the phase noise of RF accelerating structures operated off-crest. For this reason, since 2008, an RF phase fast-feedback system acting within each RF pulse has been successfully implemented at Laboratori Nazionali di Frascati, Istituto Nazionale di Fisica Nucleare (LNF-INFN) at the Sources for Plasma Accelerators and Radiation Compton with Laser And Beam (SPARC_LAB) facility, operating on both S-band ($2.856$ GHz) and C-band ($5.712$ GHz) klystrons. This paper presents the upgrade and optimization of the fast-feedback system for an S-band klystron powered by a pulse-forming network modulator. This technology introduces significantly higher intrinsic phase noise than, for instance, solid state-based modulators. It is therefore essential to minimize such phase fluctuations to keep the machine stability under control. Both the feedback hardware (electronic boards and RF circuitry) and the software (controller and user interface) have been upgraded. Tests performed at SPARC_LAB achieved a reduction in klystron-induced jitter of a factor of 30, reaching values below 15 fs rms on both power plants. Moreover, adding a remote control of the feedback loop enabled a straightforward optimization of the operating point, allowing the phase stability performance to be pushed close to its practical limits. A detailed analysis of RF phase noise measurements with the fast-feedback loop in operation is also presented. Full article

This study presents a comprehensive Life Cycle Assessment (LCA) of a perovskite/silicon (PVSK/Si) tandem photovoltaic technology. The study evaluates the environmental impact considering an application in a hypothetical PV plant. This analysis uses laboratory-scale data projected onto industrial-scale conditions, with a focus on a theoretical utility-scale photovoltaic plant located in Italy. Three electrode configurations, Au, Au/ITO, and MoOx/ITO, are assessed to identify environmental hotspots and optimize material and energy use. Among these options, MoOx/ITO produces lower environmental impacts, especially in terms of climate change (4.54 g CO₂-eq/cm² compared with 5.54 g CO₂-eq/cm² generated by Au electrode cell) and resource consumption (PVSK cell with MoOx/ITO electrode: 3.23 × 10^−f5 g Sb-eq/cm², and PVSK cell with Au electrode: 5.24 × 10⁻⁵ g Sb-eq/cm²), due to the absence of gold use. The study finally compares environmental impacts of a photovoltaic system employing tandem-cell modules with those of a system based on heterojunction (HJT) modules, highlighting the advantages of higher efficiency and reduced land consumption at equal installed capacity, leading to a 25% reduction in impacts in the land-use category. These findings support the strategic development of tandem modules for future large-scale deployment in the photovoltaic energy sector. Full article

Ultraviolet (UV) disinfection is widely used in municipal wastewater and reuse systems, yet its full-scale outcomes depend strongly on how fluence is delivered under real-water conditions rather than on nominal lamp output. This review consolidates the photochemical basis and plant-relevant limitations of UV disinfection, with emphasis on key factors such as matrix optics (e.g., UVT254, color, and turbidity/suspended solids) and particle shielding. Building from these constraints, UV-enhanced disinfection is examined as an engineering strategy that couples UV with oxidants or catalytic/physical processes to expand inactivation pathways and improve robustness in challenging effluents. Representative configurations have been reported (e.g., UV/free chlorine, UV/monochloramine) and are compared in terms of dominant reactive species and reaction networks, matrix dependence and scavenging effects, disinfection performance trends across microbial targets, and process-specific trade-offs including transformation products/disinfection byproducts, energy and chemical demands, and materials durability. Finally, practical considerations for implementation are summarized, including monitoring and control variables, validation approaches (e.g., biodosimetry, challenge testing), and operating windows that balance inactivation with risk and resource inputs, to support more reliable selection and operation of UV and UV-hybrid disinfection for water reuse. Full article

The transition toward smart grids and Industry 4.0 demands a fundamental shift in maintenance strategies, as manual inspection methods are increasingly being supplanted by automated monitoring systems. Among the advanced technologies for smart inspection, infrared imaging has advantages including non-contact operation, intuitive visualization, and predictive capabilities, which has become a cornerstone for autonomous inspection of critical power infrastructure. This review provides recent advancements in infrared imaging, with a specific focus on automated power system inspection. The discussion starts with an overview of the fundamental principles and system architectures, emphasizing the pivotal role of infrared detectors. A detailed analysis traces the technological evolution from traditional photon detectors to current uncooled microbolometers, and critically assesses emerging low-dimensional materials. The analysis highlights inherent performance trade-offs among sensitivity, operating temperature, and fabrication cost. Subsequently, the review explores advanced signal processing algorithms, such as real-time non-uniformity correction and adaptive noise suppression, which are typically implemented on FPGA platforms. Advanced optical configurations—encompassing computational imaging, lensless designs, and scattering suppression methods—are also discussed, demonstrating how their convergence enhances image fidelity and operational reliability in complex field environments. Representative application paradigms are surveyed, including drone-based transmission line inspections, patrol robots in substations, and fault diagnosis in photovoltaic plants; for each, operational efficacy and economic benefits are assessed. Despite considerable progress, several challenges persist, notably the performance–stability–cost trilemma in novel detector development, the substantial computational demands of end-to-end optimized systems, and a lack of standardization. Finally, the review outlines future research directions, such as high-performance uncooled arrays, AI-driven co-design of optics and algorithms, and the development of standardized, low-cost, intelligent inspection platforms. Full article

Pressurized pipelines are critical components in hydraulic engineering systems, including urban water supply networks and hydroelectric power plants. These systems are susceptible to air entrapment during operations such as filling and emptying, which can reduce the effective flow area and trigger critical pressure surges or sub-atmospheric conditions. One-dimensional approaches, namely the Rigid Water Column (RWC) and Elastic Water Column (EWC) models, are the most widely used due to their balance between physical accuracy and computational practicality. EWC models have been widely used to analyze transient phenomena in pipe filling and water hammer processes; however, their application to emptying operations is limited. For this reason, this study develops an EWC-based formulation for emptying operations and assesses pressure behavior through a dimensionless analysis for different air pocket configurations. The developed model couples the Method of Characteristics (MOC) with a polytropic air pocket model, enabling the representation of wave propagation effects that RWC-based models cannot capture. The formulation is verified against 24 experimental cases, yielding a mean absolute error of 0.35% in minimum pressure prediction. The results show that dimensionless air pocket ratios $x_0/L_T$ between 0.17 and 0.83 produce minimum pressures between 0.309 and 0.877 $p_{atm}^{*}$, confirming that smaller initial air pocket volumes generate the most severe depressurization conditions. The inclusion of an air valve in the most critical scenario effectively prevents sub-atmospheric pressure development, underscoring the protective role of air admission devices. These findings provide a dimensionless framework for characterizing transient pressure risk during pipeline emptying across different operational conditions. Full article

This work presents the thermodynamic design and performance assessment of an integrated process line for the separation, liquefaction, storage, and valorization of carbon dioxide (CO₂) and nitrogen (N₂) from flue gas streams. The proposed system aims to combine carbon capture with cryogenic energy storage by exploiting the thermophysical properties of the main flue gas constituents. A representative flue gas derived from complete methane combustion (9.5% CO₂, 71.5% N₂, and 19% H₂O by volume) is considered as the feed stream. The process is developed and simulated in DWSIM v9.0.5, adopting a steady-state mass and energy balance framework coupled with rigorous thermodynamic modeling of phase equilibria and unit operations. The plant configuration is based on sequential cooling, compression, and expansion stages, enabling the selective condensation of H₂O, CO₂, and N₂ at different temperature levels. The system integrates heat exchangers, compressors, pumps, turboexpanders, phase separators, and cryogenic storage tanks, while a portion of the liquefied CO₂ is reused as an energy carrier through vaporization and expansion in a dedicated turbine. The results demonstrate that the process achieves a CO₂ capture ratio of 81.7%, with a specific electric consumption (SEC) of 10.44 kWh/kg_CO2 and 1.71 kWh/kg_N2. The overall net electric demand is 1.29 kWh/kg of treated flue gas, while the round-trip efficiency (η_RT,CO2) is 18.6%. A significant amount of energy can further be recovered from the “waste” exhaust water stream (12.94 kg_L-H2O/kg_flue-gas, at 91 °C and 1.2 bar) up to 800 Wh/kg_flue-gas, improving the performance of the entire process (SEC_CO2: 3.86 kWh/kg_CO2, η_RT,CO2: 69.8%). The study confirms the thermodynamic feasibility of the proposed configuration and identifies nitrogen liquefaction as the dominant energy-intensive step. Future optimization efforts should therefore focus on reducing exergy destruction in the deep cryogenic section through improved heat integration, enhanced cold-energy recovery, optimized compression–expansion staging, and reduced pressure losses. Full article

Sediment management represents a key challenge for hydropower plants, as it requires balancing river continuity preservation with the mitigation of erosion-related damage. To identify admissible sediment loads that ensure acceptable wear levels, reliable numerical tools are required for the prediction of multiphase flow behavior under different sediment transport conditions. In this framework, the present study applies a steady-state inhomogeneous Eulerian approach to investigate the three-phase flow (water–air–sediment) inside a Pelton nozzle under different needle-opening conditions and high sediment volume fractions. The CFD model is first validated under clear water–air conditions by comparing the predicted discharge coefficient with the literature data for the same nozzle geometry. Subsequently, the validated framework is extended to sediment-laden configurations, and the resulting injector performance and jet characteristics are compared with the corresponding clear-water case. The results highlight that the presence of sediments leads to increased pressure losses and modifications of the jet structure, which may adversely affect the hydraulic performance of the downstream Pelton runner. Full article

In coastal residential areas, the combined effects of high temperature, high humidity, and weak wind conditions during summer intensify outdoor heat exposure and reduce pedestrian thermal comfort. To investigate the influence mechanisms of tree height and spatial layout on pedestrian-level thermal comfort, this study selected a typical residential community in Chengyang District, Qingdao, as the research site. Based on field meteorological observations, an ENVI-met model was established and validated. Using the existing composite greening scenario as the baseline, three tree layout types (row, cluster, and free layouts) and four height scenarios (4 m, 6 m, 8 m, and 10 m) were configured to quantitatively compare variations in physiological equivalent temperature (PET) under different planting schemes. The results indicate that tree configuration significantly affects summer thermal comfort. Its regulatory mechanism is governed not only by air temperature reduction but also by shortwave radiation interception, longwave radiation accumulation, and shading continuity. Although low-to-medium height trees can reduce local air temperature through transpiration, their limited canopy height and shading continuity restrict their ability to effectively attenuate direct shortwave radiation at pedestrian level, and in some cases may even increase mean radiant temperature (Tmrt) and PET. In contrast, 10 m tall trees arranged in row and cluster layouts can form continuous shaded cores, with the 10 m cluster layout demonstrating the best overall performance by significantly reducing Tmrt and PET. The free layout, characterized by dispersed canopies and fragmented shading, provides relatively limited thermal comfort improvement. The findings suggest that residential greening optimization should strengthen the coordination between tree height, canopy structure, and activity spaces. Tall trees should be prioritized in children’s play areas, elderly resting areas, residential entrances, main pedestrian pathways, and west-facing sun-exposed zones, while integrating building shadows and road orientation to create a continuous yet not overly enclosed shading network, thereby enhancing summer thermal adaptability in residential areas. Full article