Search Results (794)

Pumping stations serve as critical hydraulic infrastructure for water conveyance and irrigation. Sediment deposition in forebays can deteriorate intake flow conditions, increase hydraulic losses, reduce pumping efficiency, and consequently impair the long-term operational performance of pumping systems. To accurately predict sediment deposition in complex three-dimensional flow fields, we developed a dynamics-driven boundary-responsive numerical model that integrates sediment particle dynamics with real-time bed evolution. This model adopts the near-bed vertical velocity of sediment particles as the deposition discrimination criterion and dynamically updates bed topography via a mass-conservation-based boundary response strategy. The proposed method was validated against open-channel experimental data. The simulated flow structures, deposition patterns, and temporal variations in deposition thickness agreed well with the measurements, with average deviations below 4%. Compared with conventional static-boundary numerical methods, the proposed model reproduces the coupled evolution of sediment transport, flow redistribution, and bed deformation with higher fidelity. The developed framework provides an effective numerical tool for sediment deposition prediction and offers practical support for hydraulic structure optimization, maintenance scheduling, and energy-efficient operation of pumping stations with sediment-laden flow. Full article

Recently, the Internet of Things (IoT) has evolved into the Artificial Intelligence of Things (AIoT) through its combination with artificial intelligence (AI) technology and has become capable of providing intelligent services in all industrial sectors. Globally, energy consumption within buildings is continuously increasing alongside the advancement of IT and AI technologies. Since this increase is attributed to various causes—ranging from large-scale climate change to small-scale indoor environmental factors (air quality) and health factors—research aimed at reducing indoor energy consumption is actively underway. In particular, in the home environment where people spend a significant portion of their day, maintaining indoor air quality (IAQ) is critical for health, and energy conservation in heating, ventilation, and air conditioning (HVAC) systems is essential. In Korea, the number of single-person households is increasing and was expected to reach 36.1% of all households by 2024, leading people to live in increasingly smaller homes. This study aimed to verify residents using contactless facial recognition to prevent pandemics such as COVID-19 and to provide comfortable indoor air quality. Resident facial recognition was performed by identifying residents’ faces in images captured by the Pi camera using OpenCV’s Haar feature-based cascade classifier. Indoor air quality measurements were conducted in four indoor locations, measuring various environmental factors (PM_2.5, CO₂, etc.) based on environmental sensors and the IoT. Furthermore, to manage indoor air quality, AI was utilized based on the measurement data to classify the four spaces, with a success rate of 96%. Additionally, considering the indoor area of the experimental environment (97 m²), it was confirmed that operating a 70 W air purifier only when the resident is indoors can reduce power consumption by approximately 33–75% compared to running it 24 h a day. Full article

Traditional stone-slab dwellings in Southwest Henan possess distinctive regional characteristics and inherent climate adaptability. However, previous studies have mainly focused on individual aspects of indoor environmental performance, while integrated optimization of daylighting, thermal environment, and renewable energy utilization under the constraints of heritage conservation has received limited attention. This study systematically evaluates the indoor light and thermal environment of traditional stone-slab dwellings through field measurements and validated numerical simulations, and proposes appropriate optimization technologies. The numerical model was first validated against field measurement data and subsequently employed to evaluate the proposed optimization strategies. The results indicate that the daylight factor in the main occupied rooms does not satisfy current standard requirements. In terms of thermal performance, indoor temperatures are excessively high in summer and excessively low in winter, while the relative humidity remains close to saturation. Based on psychrometric chart analysis and the conservation requirements of traditional dwellings, a series of optimization strategies are proposed and validated. The results demonstrate that the addition of skylights, the application of 60 mm polyurethane (PUR) insulation boards to the roof and exterior walls, and the installation of transparent Low-E insulating glass units for exterior windows are effective technologies for improving the indoor light and thermal environment of stone-slab dwellings in Southwest Henan. The potential for solar energy utilization is also evaluated. This study provides an integrated framework for the environmental optimization of traditional stone dwellings and offers practical guidance for their sustainable conservation, performance enhancement, and renewable energy utilization. Full article

This study develops a one-dimensional covariant Helmholtz model for a vector-valued wave field transported along a circular helical centerline and represented in the Frenet–Serret frame. For a helix with constant curvature $\kappa >0$ and torsion $\tau \ne 0$, the geometric coupling is described by a constant skew-symmetric connection matrix $\mathsf{\Omega }\in \mathfrak{so}\left(3\right)$. The covariant Helmholtz operator is shown to admit an exact gauge reduction to the flat componentwise Helmholtz operator through $u\left(s\right)=e^{-\mathsf{\Omega }s}y\left(s\right)$. Thus, within the one-dimensional centerline formulation, the helix preserves the operator spectrum while redistributing the observed Frenet components through parallel transport. The closed-form solutions show that a monochromatic input with wavenumber k is decomposed into a carrier and two geometric sidebands governed by the Darboux rotation rate $\lambda =\sqrt{{\kappa }^2+{\tau }^2}$. In the sub-geometric regime $k<\lambda$, the lower algebraic sideband is represented by the positive observable wavenumber $q_{-}=|k-\lambda |$, with associated scale $T_{\mathrm{beat}}=L_{-}=2\pi /q_{-}$. The lossless energy analysis proves conservation of the total averaged energy and its redistribution among the carrier and observable sidebands. A representative helical acoustic-channel design is then examined as a conceptual realization of the centerline model. Monte Carlo perturbations and additive-noise tests show that the predicted sideband locations, lower-sideband scale, and energy partition remain stable under prescribed fabrication tolerances and spectrally identifiable under weak and moderate measurement noise. Full article

Family-owned accommodation enterprises, including small and medium-sized enterprises (SMEs), play a critical role in tourism economies, yet their contribution to environmental sustainability transitions remains underexamined. Drawing on the Resource-Based View (RBV), this study examines the relationship between environmental sustainability practices and perceived business performance in family-owned accommodation SMEs in Greece, considering cost advantage and differentiation advantage as parallel mediators. Data were collected through a structured questionnaire completed by representatives of 136 family-owned accommodation SMEs between March and April 2026. Environmental sustainability practices were measured as the breadth of adoption of 22 operational practices related to energy efficiency and low-carbon technologies, water conservation and management, and waste reduction and circular resource management. Business performance was assessed through a broad perceptual composite, whereas cost advantage and differentiation advantage were assessed using reflective multi-item scales. The results show that environmental sustainability practices were positively related to perceived business performance, cost advantage, and differentiation advantage. In the main mediation model, the indirect association through cost advantage was statistically significant, whereas the indirect association through differentiation advantage was not statistically significant. These findings suggest that, in family-owned accommodation SMEs, operational environmental practices may be more readily connected with business outcomes through resource efficiency, cost control, and operational consistency than through a differentiation pathway. The study refines the application of the Resource-Based View by showing how established competitive mechanisms operate when sustainability is represented by the breadth of specific operational practices in the resource-constrained context of family-owned accommodation SMEs. Full article

Standard pushers for the relativistic equations of motion of a charged particle in an electromagnetic field—Boris, Vay, Higuera–Cary—do not, in general, preserve the full symplectic structure of the underlying Hamiltonian system, while high-order non-symplectic schemes such as Runge–Kutta accumulate secular error over long times. We propose a two-stage, symmetry-preserving framework (SP-PINN) for the 3+1-dimensional relativistic dynamics of a charged particle in a prescribed field, including a focused Gaussian laser pulse, that pairs a physics-informed neural network with an explicit symplectic integrator: the network learns a surrogate relativistic Hamiltonian, while the integrator—which is not itself learned—advances it. In Stage 1, an unsupervised physics-informed neural network learns the surrogate from the covariant equations of motion using a Lorentz-invariant loss that enforces the mass-shell constraint $\mathcal{H}=m{c}^2\gamma$; in Stage 2, the surrogate is advanced with an explicit symplectic map built on Tao’s extended phase space, valid for the non-separable relativistic Hamiltonian. To isolate the geometric integrator from neural-network approximation error, every benchmark figure advances the analytic relativistic Hamiltonian through Stage 2, the learned Stage-1 surrogate being assessed separately. We benchmark against the Boris pusher and Runge–Kutta on three core test problems (adding the Higuera–Cary pusher in the symplecticity diagnostic), supplemented by plane-wave, ensemble, and pulse-family studies, and we measure the first Poincaré–Cartan loop invariant directly as a quantitative diagnostic of symplecticity. The magnetic-field test illustrates the contrast between bounded and secular error growth: Runge–Kutta drifts secularly, the Boris pusher conserves the invariants to machine precision as a volume-preserving gyro-integrator, and the symplectic map keeps the error bounded for all time; on a non-integrable magnetic trap, where no exact volume-preserving rotation exists, the symplectic map alone keeps the energy error bounded. The learned surrogate is the current accuracy bottleneck—not yet competitive with the conventional pushers for the static cases—but for the demanding laser case, a vector-potential light-cone reformulation reduces this surrogate error to $(3.0\pm 0.1)\times {10}^{-4}$ (three seeds) and yields learned trajectories that remain phase-coherent over essentially the whole interaction. The framework targets laser–plasma acceleration, synchrotron-radiation modeling, and particle tracking. Full article

Agrivoltaic (AV) systems represent a promising strategy for integrating renewable energy production and agricultural activity on the same land unit, while contributing to soil water conservation under increasingly frequent drought conditions. This preliminary, single-site case study investigates the effects of a horizontal biaxial tracking AV system on soil water dynamics in a durum wheat field in the Po Valley (Borgo Virgilio, Mantua, Italy) over a full monitoring period, covering the final crop growth stages and the post-harvest bare soil phase (May–December 2024). Monitoring of soil temperature, volumetric water content (VWC), and soil water potential (SWP) was conducted at four depths (15, 30, 45, and 60 cm) at one representative monitoring station per treatment, comparing soil under AV cover (AVC) and in unshaded conditions (UC), located 10 m apart. Paired VWC and SWP measurements were used to derive site-specific soil water characteristic curves (SWCCs) and to calibrate the agro-hydrological model CRITERIA-1D, which was used to estimate available water (AW) in the first 80 cm of depth for both treatments. Measured VWC values were higher in the AVC profile than in the UC profile at all monitored depths throughout the May–September period, with differences persisting, although at lower values through October–December. Estimated AW was consistently higher under AVC than in UC during both the dry and wet periods. Despite higher VWC, the AVC profile showed more negative average SWP values at all depths during summer. This pattern is consistent with the shape of the derived SWCCs and may point to differences in water-retaining capacity between the two profiles, possibly related to structural modifications induced by 13 years of AV system operation. These preliminary findings suggest that AV systems could potentially improve soil water availability in the root zone of rainfed cereal crops and propose the hypothesis that long-term AV cover may act as a driver of changes in soil hydraulic properties, with implications for the sustainability and climate resilience of dryland farming systems. However, given the design of this case study, with only one monitoring point per treatment, the observed differences reflect the specific monitored locations and cannot fully disentangle the AV treatment effect from pre-existing spatial heterogeneity in soil properties. The preliminary results obtained in this study should therefore not be generalised beyond the specific conditions of this case study, and the interpretations proposed here should be treated as unproven hypotheses rather than established conclusions. Further studies with spatial replication and multi-year monitoring are needed to confirm these patterns. Full article

In this study, we explore the static and dynamic mechanical responses of layered cemented backfill subjected to blasting loads. Variable-rate uniaxial compression tests and Split Hopkinson Pressure Bar (SHPB) numerical simulations were performed on specimens with three different interlayer cement-to-tailings ratios. All samples were cured for 28 days before testing. The test results reveal that uniaxial compressive strength rises and then falls with increasing loading rates, and mixed tensile-shear failure dominates quasi-static loading conditions. The interlayer cement-to-tailings ratio dominates the bearing capacity of backfill. At the test loading rate of 0.02 mm/s, lowering the interlayer ratio from 1:4 to 1:8 sharply reduces peak strength from 5.595 MPa to 1.285 MPa, with a total drop of 77.0%. SHPB simulation results show obvious strain-rate hardening under dynamic impact. For samples with an interlayer ratio of 1:4, dynamic compressive strength increases from 5.38 MPa to 6.16 MPa as impact velocity rises from 4 m/s to 13 m/s, a 14.5% improvement caused by rapid compaction of internal micropores. Combining damage mechanics and energy conservation principles, we establish a dynamic damage constitutive model that couples inherent layered interfacial damage with blasting-induced dynamic disturbance. Model predictions match experimental measurements well. The peak strength error is only 1.3% at a loading rate of 0.005 mm/s, and peak deviations for all test cases are controlled within 5.0%. This work quantitatively clarifies the static and dynamic mechanical evolution of layered cemented backfill, and provides solid theoretical support for mixture proportion design and blasting stability assessment in high-stage sequential backfilling mining. Full article

High renewable penetration, distributed energy resources, and fast-varying electric loads are shifting smart-grid planning from energy-balance simulation toward quality-aware operational assessment. Full-unit benchmark models (FULL) preserve unit commitment, ramping memory, and reserve feasibility but are expensive for repeated annual studies, whereas conventional equivalent aggregation (EQ) can overstate the realizable flexibility of heterogeneous units. This paper proposes quality-aware flexibility-envelope aggregation (QFEA), which separates units by inherited boundary state, ranks them by renewable-following flexibility, constructs conservative cluster envelopes, and couples reduced optimization with feasible disaggregation and state write-back. The model coordinates renewable curtailment, reserve sufficiency, tie-line ramping, and a normalized quality-stress proxy without claiming to replace detailed power-flow, harmonic, or electromagnetic studies. In the nominal single-region case, QFEA reduces the number of commitment objects by 46.2% and computation time by 63.7%, while limiting total-cost deviation to 1.1% and renewable-curtailment deviation to 0.2 percentage points. In 20 matched 24-h stress scenarios, its mean quality-stress index is 2.56%, compared with 2.58% for FULL and 6.57% for EQ. A separate 13–104-unit simplified scaling test keeps inverse-mapping closure error below 5.2 × 10⁻⁹ MWh and disaggregation below 1.3% of measured end-to-end time. The results identify QFEA as a traceable intermediate model for renewable-integration screening when annual computational efficiency and implementable unit trajectories are both required. Full article

Continuous stream-oriented data-plane processing in 5G/6G edge nodes increases the energy and latency cost of CPU-centered execution. This paper studies this boundary on an Intel Cyclone V SoC FPGA and proposes Hardware Accountability: a partitioning discipline in which Linux performs supervisory control while high-rate payload processing remains in programmable logic. The evaluation uses the Strumok stream cipher, adopted as the Ukrainian national standard DSTU 8845:2019, as a secure fronthaul/payload workload with XOR- and shift-dominated logic. On the evaluated USB 2.0/Cortex-A9/Linux path, the software-driven stream approaches saturation near 20 MSPS. In contrast, the RTL core reaches 9.6 Gbps at 150 MHz and occupies less than 6% of the available logic. Quartus Prime vectorless power analysis estimates 24.00 mW dynamic power for the RTL computational core, corresponding to approximately 2.5 pJ/bit. Control-plane measurements show P99 orchestration jitter below 1 ms under Spatial Isolation, conservative full context reloads near 1290 per second, and more than 7200 shadow-register context/state update operations per second. A design-space exploration then projects an 83.2 Gbps multi-core data path when external DDR traffic is avoided through internal stream aggregation and elastic buffering. Full article

Background/Objectives: Glycosylation can affect vaccine antigen structure and function, making site-specific glycan characterization relevant to antigen quality and comparability. However, quantitative approaches for comparing glycan microheterogeneity remain limited. This study evaluated the utility of the glycopeptide abundance distribution spectra framework for measuring similarity among site-specific glycosylation profiles in vaccines and antigen reference reagents across manufacturing conditions. Methods: Intact N-linked glycopeptides were characterized by nanoflow liquid chromatography–tandem mass spectrometry with stepped-energy fragmentation. Products included monovalent and quadrivalent influenza antigens produced in embryonated eggs, Madin–Darby canine kidney cells, or Spodoptera frugiperda cells, together with a SARS-CoV-2 spike vaccine produced in Spodoptera frugiperda cells and a Chinese hamster ovary cell-produced varicella-zoster virus glycoprotein E vaccine. Site-specific glycan distributions were represented as distribution spectra and compared using NIST MS Search software. Dot-product scores ranging from 0 to 999 quantified similarity. Results: Across measured glycosylation sites, distributions clustered into six recurrent classes. Similarity was high for replicate analyses, conserved influenza components across annual formulations, and matched components from different suppliers within the same production platform (similarity scores = 978, 961, and 960, respectively). Similarity was lower between sites within the same protein, between influenza strains, and between production sources (similarity scores = 554, 540, and 209, respectively). Among production-source comparisons, egg- and Madin–Darby canine kidney-derived profiles were most similar, and the overall ordering of glycosylation similarity was consistent with broad phylogenetic relatedness among production hosts. Conclusions: Distribution spectra-based similarity scoring of vaccine glycoproteins provides a quantitative, reusable approach for documenting site-specific glycosylation microheterogeneity. Using this method, we can conclude that production source is the dominant contributor to variation, whereas replicates, annual formulations, and suppliers within the same production platform are highly consistent. Full article

Channel time dispersion causes inter-symbol interference (ISI) which is mitigated by the Orthogonal Frequency Division Multiplexing (OFDM) symbol cyclic prefix (CP). However, CP is an overhead which reduces spectral efficiency and increases energy per delivered bit. In Long Term Evolution (LTE), the widely deployed normal CP corresponds to a fixed overhead of about 7% (4.69 $\mathsf{\mu }$s), which is conservative for many practical environments and is equivalent to path-length variations on the order of 1.4 km. This paper address CP sizing from an energy-efficiency viewpoint for OFDM-based 4G/5G radio networks. We combine an analytical model based on delay spread statistics with link-level simulations to determine a reduced CP that remains effective for ISI mitigation across indoor-to-urban scenarios. Optimal CP intervals are derived for the LTE M-ary Quadrature Amplitude Modulation formats (4-QAM, 16-QAM, and 64-QAM) and validated using standard delay-dispersive mobile radio channels. Results indicate that CP can be reduced by 70–95% relative to the LTE normal CP in typical deployments, yielding measurable net-throughput improvements and energy savings without compromising error-rate targets, supporting greener wireless communications. Full article

Saudi Arabia is a water-stressed nation and meets much of its daily demand through desalination, an energy-intensive process with a significant carbon footprint. As a Muslim-majority country, residents perform ablution before five daily prayers, making this activity a substantial yet under-quantified component of residential water use. This study focuses on household-level ablution water savings across 13 regions for both Saudi and non-Saudi households by replacing standard taps with a flow rate of 5.7 L/min with a proposed Saudi Standards, Metrology and Quality Organization (SASO)-compliant ultra-low-flow tap (1.9 L/min). Moreover, this study evaluates this ultra-low-flow tap as an environmental technology capable of reducing ablution water consumption and found that per capita savings are identical for both demographic segments, but the total household savings differ because Saudi households are larger, supporting sustainable water management. Results show that under the stated assumptions, full national adoption of the proposed tap would reduce monthly ablution water use from 27 million m³ to 9 million m³, conserving 212.14 million m³ annually with 67% efficiency and offsetting 702,198 tonnes of desalination-related carbon emissions. This highlights the effectiveness of deploying a simple water-saving technology in a water-stressed environment. Conservation potential is concentrated in Riyadh, Makkah, and the Eastern Province due to their high household counts. A four-year phased implementation roadmap is proposed, beginning with 25% adoption in year one (53.01 million m³ annual savings), expanding to moderate-impact regions in year two, and reaching 75–100% adoption nationwide by years three and four. The findings demonstrate how simple and commercially available water-efficient technology can contribute to sustainable resource management by simultaneously reducing water demand, energy consumption associated with desalination, and related greenhouse gas emissions. This study supports Saudi Arabia’s Vision 2030 water strategy and can potentially support UN-SDGs 6, 7, and 13 by demonstrating the substantial water, carbon, and economic benefits of a simple, commercially available tap of 400 SAR. In addition, the study develops a regionally prioritized technology deployment framework that can support decision makers in planning large-scale implementation. The analysis assumes that household members perform ablution five times daily for approximately one minute, based on field measurements, and they require validation of projected gains through actual implementation. Full article

This study evaluated the individual and interactive effects of straw management, tillage systems, and wheat growth stages on surface energy balance (SEB) dynamics in a semi-arid wheat production system, with particular focus on net radiation (Rn), sensible heat flux (H), latent heat flux (LE), Bowen ratio (β), and energy partitioning (EP). A field experiment was conducted during the 2022–2023 growing season using a split–split plot design with two straw management treatments, four tillage systems, and three growth stages. Surface energy balance components were estimated through field-based micrometeorological measurements. Data were analysed using ANOVA, variance partitioning analysis, and Pearson correlation analysis. All experimental factors significantly affected SEB components, although growth stage represented the dominant source of variability, accounting for 42–58% of total variance. Flowering stage consistently promoted the highest LE values and the lowest β and EP values, indicating enhanced evaporative cooling during maximum crop development. Conservation-oriented tillage systems substantially modified thermal partitioning, with no-tillage (NT) significantly increasing LE and reducing H relative to conventional tillage (CT). The combination of straw incorporation and NT during flowering (IS + NT + S2) produced the highest LE value (129.15 W m⁻²) and one of the lowest H values (18.35 W m⁻²). Bowen ratio progressively decreased from CT (8.57) to NT (1.44), confirming a shift from sensible to latent heat exchange under conservation-oriented management. Crop phenology and conservation-oriented soil management jointly regulated thermal partitioning and evaporative cooling in semi-arid wheat systems. NT combined with straw incorporation substantially enhanced latent heat exchange while reducing sensible heating, particularly during flowering. This study provides novel field-based evidence regarding the combined influence of straw management, tillage systems, and wheat phenology on SEB dynamics under semi-arid conditions, contributing to improved understanding of land–atmosphere interactions and climate-adaptive agricultural management strategies. Full article

Field measurements undertaken in six paired primary school classrooms in Anambra State, Nigeria, previously demonstrated that interlocking compressed earth block (ICEB) classrooms maintained significantly lower occupied-hour temperatures than adjacent sandcrete block (SCB) classrooms. This study applies DesignBuilder/EnergyPlus simulation, evaluated against field measurements, to investigate the physical mechanisms underlying this observed thermal advantage and to explore seasonal performance beyond the period accessible through field monitoring. Simulation models were developed using literature-derived thermophysical properties and validated against field measurements collected at Awkuzu Primary School on 2 July 2024. Model accuracy was assessed using ASHRAE Guideline 14 metrics. The ICEB model achieved NMBE of −6.4% and CV(RMSE) of 6.8%, satisfying both recommended thresholds. The SCB model achieved CV(RMSE) of 15.6%, while NMBE of −14.0% marginally exceeded the recommended threshold because of conservative TMYx boundary conditions. Results indicate that the superior wet-season performance of ICEB classrooms is attributable to the interaction between high thermal mass (μ = 0.31; φ = 9.1 h) and continuous cross-ventilation. Parametric crossover simulations demonstrated that ventilation was the dominant cooling mechanism, while ICEB wall thermal mass provided an additional independent thermal benefit of approximately 0.31 °C. This material contribution is secondary in magnitude to the ventilation effect and is not presented as a standalone practical advantage. Dry-season simulations suggested a possible reversal of performance under near-calm harmattan conditions; however, the magnitude and direction of this effect remain uncertain because of EPW boundary-condition limitations. The findings suggest that classroom thermal performance depends on the interaction between envelope thermal mass and ventilation configuration rather than material properties alone and highlight the potential importance of controllable ventilation in naturally ventilated educational buildings in tropical climates. Full article