The use of Pulsed Electric Fields (PEF) has been successfully implemented in the potato industry, but its application in the vegetable industry remains restricted due to limited knowledge on the behaviour of various plant tissue types in subsequent processing steps. This study investigates the heterogeneous effects of PEF across various plant tissues with differing structural complexities, including mostly homogeneous tissues (sweet potato), tissues with layers of different conductivity (red beetroot), tissues containing lignified areas (broccoli), and materials exhibiting structural heterogeneity (carrot, parsnip). PEF treatments were applied at electric field strengths ranging from 0.4 to 3.0 kV/cm, with specific energy inputs from 0.01 to 6.30 kJ/kg. Electrical impedance measurements were conducted before and after treatment, as well as after a 10-min holding time to monitor the effects of water redistribution. Additionally, texture analysis was performed using compression measurements to assess the mechanical response of PEF-treated tissues. The results indicate that plant tissue complexity strongly influences the apparent uniformity of PEF treatment due to factors such differences in conductivity, as air pockets, and variations in water distribution. Additionally, tissue orientation relative to the electric field has a strong influence on treatment efficacy, especially for structurally inhomogeneous materials. The assessment methods show different sensitivities to changes in the tissue, depending on the applied treatment intensity.
This study investigates the response of a parent tunnel (PT) lining to volume loss and cross-passage (CP) shape and how it affects the stress redistribution and deformation of the PT lining around the opening for shallow tunnels in cohesionless soils. Three-dimensional finite-element parametric analyses were carried out using the Hardening Soil with Small Strain constitutive model simulated varying soil densities, CP/PT size ratios (0.25-0.90), PT volume-loss values (0.25-1.0%) and four CP geometries (circular, square, modified horseshoe, inverted-D). Results show that increasing PT volume loss generally reduces residual hoop stresses at CP springlines and crown/invert while producing higher longitudinal stresses at the springlines. CP shape controls stress arching: circular openings concentrate hoop stresses at the springlines, whereas square, inverted-D and modified-horseshoe shapes transfer higher stresses to crown/invert regions. CP deformations decrease with increasing PT volume loss. Among the shapes considered, square openings exhibit the largest vertical deformations, while circular openings show the least. Normalised force-moment plots are developed to guide lining reinforcement around CPs and to inform shape-specific reinforcement detailing aimed at miti-gating localised stress concentrations.
Wind power is widely recognized as a key component of future net-zero energy systems. However, substantial variability among current wind resource and power simulations used for wind farm deployment limits the reliability of siting and system integration decisions. Therefore, we present a transparent, open source, validated and evaluated, global wind power simulation workflow for the renewable energy simulation tool ETHOS.RESKit. As the first wind simulation workflow using the new Global Wind Atlas 4 and the fifth iteration of the European Center for Medium-Range Weather Forecasts Reanalysis, it is capable of simulating time-resolved energy output of wind turbines with high spatial resolution and customizable designs for both onshore and offshore wind turbines. The tool has undergone an extensive validation and calibration process using over 18 million global measurements from meteorological masts for wind speed bias correction and 8 million measurements from wind turbine sites across 6 countries during 2002 to 2021. In comparison with measured energy yield from wind turbine sites, we achieve a global average capacity factor mean error of 5.6% and Pearson correlation of 0.844. In addition, we evaluate its performance against annually aggregated energy production data from operational wind farms and country-level wind power generation statistics reported by energy agencies, demonstrating its accuracy across multiple spatial and temporal scales with a mean error of only 0.6%. Additionally, a final calibration step ensures alignment of the simulation with real world statistics. The release of ETHOS.RESKit is a step towards a fully open source and open data approach to accurate wind power modeling by incorporating comprehensive simulation advances in one model.
Rising concentrations of atmospheric CO2 (ca) increase plant photosynthesis (An) and reduce stomatal conductance (gs). This increases the intrinsic water-use efficiency (iWUE = An / gs), a major proxy of tree adaptation to climate change. However, whether an increase in iWUE leads to a concomitant increase in tree growth remains in dispute, prompting interest in theoretical links between iWUE and tree productivity. Here using an optimality theory for kinetics of stomatal aperture, we establish an envelope delineating maximal relative increases in tree productivity that can be inferred/expected from relative increases in iWUE. The resulting expressions are used to interpret relations between iWUE (an observable proxy) and tree growth (the target variable), using available experimental data from manipulation experiments and tree-ring isotopes. While rising ca increases iWUE, proportional increases in tree growth are unlikely given ameliorating environmental (for example, rising atmospheric dryness) and anatomical/physiological (for example, tree height) influences.
Root-reinforced soils are increasingly used in ecological slope protection, yet their mechanical behavior remains insufficiently described in current numerical modelling approaches. In this study, a hypoplastic constitutive model for root-reinforced soil is proposed. The mechanical reinforcement effect of plant root is incorporated by modifying both the critical state stress ratio and the critical void ratio as functions of root content. The proposed model is implemented within a finite element framework using an explicit integration scheme combined with a stress-correction procedure to ensure numerical stability. A series of benchmark simulations, including triaxial and direct shear tests on root-reinforced soil, are performed to validate the model performance. The applicability of the model is further evaluated through numerical simulations of rainfall-induced instability in vegetated slopes. The results indicate that the proposed approach provides a practical framework and an effective computational tool for analyzing and designing vegetated slopes.
