Search Results (1,051)

Dairy cattle are particularly susceptible to welfare challenges that can negatively impact their behaviour, physiological responses, milk yield, and overall health. These challenges include rough handling by unfamiliar people, extreme climatic conditions, inconsistent feeding, regrouping, and transportation. This pilot study investigated the interrelationships between behavioural and physiological responses and milk production of dairy cows reared in a smallholder stall housing system, restricting cow movement to standing and lying down in the Rajshahi district of Bangladesh. Fifty cows were observed, with all cows assessed over two days. Video recordings were made using a smartphone during the morning milking routine, focusing on specific behaviours: ear position (upright, forward, backward, downward), sniffing, stepping, and tail movement. Observations were conducted during the first two minutes after the start of the milking process manually. Physiological responses recorded included rectal temperature, vaginal temperature, and heart rate. Productivity outcomes include body condition score (BCS), milk yield per milking, daily milk yield, and milking frequency. Environmental data were collected to calculate the Temperature-Humidity Index (THI), which averaged 84.5 (±1.78 SD), exceeding the thermal comfort zone for dairy cattle (THI < 72). Statistical analyses comprised principal component analysis (PCA) to determine the most descriptive variables. Pearson correlation assesses the direction and strength of relationships between variables, and simple linear regression to evaluate milk production variables using all other variables as predictors. Results showed that cows displaying an upright ear position during milking had a positive relation with average daily milk yields (r = 0.456, p = 0.001). Milk yield was negatively correlated with THI (r = −0.331, p = 0.02), forward ear position (r = −0.356, p = 0.01), kicking (r = −0.531, p < 0.001), and sniffing behaviour during milking (r = −0.511, p < 0.001). The daily milk yields were positively correlated with body condition scores of milking cows (r = 0.661, p < 0.001). Rectal and vaginal temperatures were positively associated with each other (r = 0.777, p < 0.001). Similarly, rectal temperature and heart rate were positively associated with each other (r = 0.511, p < 0.001). Therefore, ear position, kicking, and sniffing behaviour during milking were used to assess emotional states, with forward ears associated with signs of stress. Healthy cows with higher body condition scores (BCS) produced more milk, requiring farmers to milk them more than twice a day. This pilot study highlights key behaviour and physiological responses relevant to stress and milk production, and thus overall welfare. For greater generalisability, future research should incorporate larger sample sizes and repeated environmental assessments over extended periods. Full article

In this study, a liquid-cooled Battery Thermal Management System (BTMS) incorporating aluminum heat-conducting blocks was numerically investigated to enhance the thermal performance of lithium-ion battery modules used in electric vehicles. The proposed system was designed for a battery module consisting of cylindrical lithium-ion cells, and the effects of different geometric configurations on thermal behavior were analyzed using the Computational Fluid Dynamics (CFD) method. To efficiently evaluate the multi-parameter design space with reduced computational cost, a Taguchi L9 orthogonal experimental design was employed. The cooling channel configuration, aluminum heat-conducting block height, and battery pack geometry were considered as the primary design variables. The performance of each design configuration was assessed based on maximum temperature (T_max) and temperature uniformity (ΔT). Furthermore, an Analysis of Variance (ANOVA) was conducted to quantify the influence of the design parameters on the thermal performance of the system. The results revealed that the configuration comprising eight cooling channels, a 65 mm aluminum block height, and a 1 + 8 cylindrical battery arrangement exhibited the best thermal performance, achieving a maximum temperature of 303.45 K and a temperature difference of 1.25 K. The optimal design configuration provided a more uniform temperature distribution within the battery module, thereby enhancing thermal safety and operational reliability. Overall, the integration of CFD and the Taguchi method offers a systematic and efficient optimization framework for BTMS design, enabling effective evaluation of design alternatives with a reduced number of simulations and shorter computational time. Full article

Snow depth and persistence strongly influence ground–atmosphere energy exchange, meltwater input, and the thermal regime of rock glacier systems, yet high-resolution snow monitoring remains scarce in the Southern Carpathians. This study uses multi-temporal Unmanned Aerial Vehicle (UAV) Structure-from-Motion (SfM) photogrammetry to map snow-depth variability and microtopographic controls on the Galeșu Rock Glacier, Retezat Mountains. Eight UAV surveys were conducted between 2023 and 2025, including seven snow-covered acquisitions and one snow-free reference survey in August 2025. Snow depth was derived by DEM differencing and analyzed against morphometric indices, mainly profile curvature and relative topographic position. Results reveal strong spatial heterogeneity, with recurrent snow accumulation in furrowed, concave, and depressional sectors and reduced snow depth on local topographic highs. The 2024 surveys showed substantially deeper snow than 2025, with mean snow depths of 1.82 m in February and 1.62 m in March 2024, compared with 0.72 m and 0.83 m in February and March 2025. April 2023 displayed the deepest snowpack, with a mean snow depth of 2.27 m. Class-based analysis showed median contrasts of 2.30 m in 2024 and 1.20 m in 2025 between strong negative and strong positive curvature classes. These findings demonstrate that rock glacier microtopography exerts a first-order control on snow accumulation and persistence, providing a basis for future studies linking snow redistribution to ground thermal regimes, meltwater pathways, and ground-ice preservation in marginal periglacial environments. Full article

In the current work, pulsating airflow and an external heat source are proposed to improve the evaporation performance of falling films. A volume of fluid (VOF) multiphase flow model is established based on the commercial software ANSYS Fluent 2023 R1 (ANSYS, Inc., Canonsburg, PA, USA) to simulate the falling film evaporation process. Numerical simulations are conducted under combined working conditions with variable average inlet velocity (u₀), relative pulsating amplitude (A), and wall heat flux (q_w). The spatial and temporal distributions of physical fields are visualized via numerical contours and characteristic curves, and the heat and mass transfer enhancement mechanism is revealed from three aspects, namely, the promotion of driving potential difference by wall heat flux, the increase in heat and mass transfer gradients induced by pulsating airflow, and the synergistic effect of the above two factors. The results indicate that the evaporation ratio (Ψ) increases monotonically with the rise of u₀, with a maximum growth rate of 83.8%. By contrast, under the condition of fixed A₀ = 1 m/s while varying u₀, the evaporation ratio exhibits a convex variation with the relative amplitude A = A₀/u₀, and the global optimal value is achieved at A = 1/6, corresponding to u₀ = 6 m/s and A₀ = 1 m/s. Comparative analysis demonstrates that wall heat flux exerts a more significant influence on evaporation performance than pulsating airflow. Specifically, the evaporation ratio at q_w = 10,000 W/m² is 3~4 times higher than that under the adiabatic wall condition. The reliability of the numerical model is first confirmed by comparing the predictions with published experimental data for vertical falling film evaporation. Based on this validated model, the quantified parametric effects and optimal operating conditions provide practical design references for falling film evaporators in seawater desalination and related thermal separation applications. Full article

This qualitative study develops morphological design principles for thermally formed passive adaptive grippers within an accessible 4D-printing approach. A practice-based morphological exploration was conducted through 18 PLA+ prototypes fabricated by Fused Deposition Modeling and thermally formed through controlled hot-water immersion. The study treats the two-dimensional pre-forming sheet geometry as the central design variable and examines how variations in flat-pattern organization affect the activated three-dimensional gripper. This shifts attention from optimizing a single predefined gripper toward understanding how form variations generate design knowledge. The prototypes were organized into two morphological families: a convergence-based radial gripping family and a guided cylindrical wrapping family. Functional and morphological readings of the catalogue showed that flat-pattern decisions shape grasp typology, functional role distribution, approach geometry, structural continuity, and the behavioral envelope of the activated form. The study proposes seven morphological design principles linking flat-pattern operations to three-dimensional gripping consequences, while also showing that the two families form a continuum of morphological possibilities rather than discrete categories. Across the prototype lineage, design knowledge accumulates through comparison and can be recombined into more resolved configurations. This paper offers a planning vocabulary for developing passive adaptive gripping structures before performance optimization or application-specific engineering begins. Full article

Laser Powder Bed Fusion (LPBF) is widely employed for manufacturing complex metallic components; however, process-induced distortion, residual stress, and thermal accumulation remain major challenges affecting dimensional accuracy and structural integrity. In the present study, a three-dimensional thermo-structural finite element model was developed to investigate the combined influence of component orientation and base plate material on the thermo-mechanical behavior of LPBF-fabricated Inconel 718 components. In addition, an integrated optimization methodology combining response normalization, a weighted sum performance index, and radar chart analysis was adopted to realize the optimal combination of the process variables by a simultaneous consideration of distortion, residual stress, and temperature. Accordingly, five part orientations and five different base plate materials were examined under identical processing conditions through 25 simulation cases. The obtained results revealed that component orientation represents the dominant factor controlling distortion and residual stress development, whereas both orientation and base plate material significantly affect component temperature. The inclined orientations generated the highest distortion levels, while the vertical configuration exhibited the highest residual stresses. In contrast, the horizontal orientation along the X-direction demonstrated the most balanced thermo-mechanical performance. Furthermore, AlSi10Mg base plate material provided the lowest thermal accumulation due to its high thermal conductivity. The integrated optimization analysis based on radar chart assessment and performance index evaluation identified the Horizontal-X/Ti-6Al-4V and Horizontal-X/AlSi10Mg configurations as the most favorable LPBF conditions. These findings provide practical guidelines for selecting build orientation and base plate material to reduce thermo-mechanical defects, thereby improving the dimensional accuracy and manufacturing reliability of LPBF-fabricated Inconel 718 components. Full article

This work presents the design evolution, fabrication, and characterisation of an additively manufactured ring-type thermal airflow sensor for in-pipe flow monitoring, developed employing exclusively Fused Deposition Modelling (FDM) additive manufacturing technology and a commercially available Carbon Nanotube (CNT)-enriched Biopolymer Polylactic Acid (PLA) composite filament. The design evolution proceeds through three progressive stages. In the first stage, a flat heater element is characterised through Constant-Current (CC) Joule heating experiments in order to derive the corresponding Temperature Coefficient of Resistance (TCR) and Thermal Resistance from the obtained experimental data. Consequently, a Finite Element Method (FEM) model implemented in COMSOL Multiphysics^® and calibrated with the extracted material parameters validates the experimental temperature–power relationship and predicts the convective cooling behaviour at various airflow velocities. In the second stage, the geometry is optimised by introducing a conductive trace with a reduced-cross-section central region; as a result, an equivalent thermal localisation is achieved at approximately 26% lower supplied power with respect to the initial heating element, enabled by the design freedom inherent in the FDM process. We should note that the specific sensing geometry can also be directly embedded into any 3D-printed structural component (e.g., a bracket or housing), enabling simultaneous local thermal heating and/or thermal monitoring together with structural functionality within a single printed part. In the third and final stage—the target device—a fully monolithic ring-type airflow sensor is directly integrated into a 3D-printed pipe segment during the printing process. Under constant-current excitation at 40 mA, the device exhibits a monotonically decreasing resistance with increasing airflow (ΔR ≈ 117 Ω over 0–4 m/s) due to convective cooling, while in a single flow-interruption cycle, approximately 79% of the flow-induced resistance change was recovered upon flow removal, with a residual offset of approximately 3% of the heated baseline. A coupled electrothermal FEM model of the device further supports the experimental response by comparing the simulated temperature rise with the values inferred from resistance measurements, while also clarifying the role of the effective internal convective cooling conditions imposed by the pipe geometry. Key features of the proposed device are low raw-consumables cost, fast on-site manufacturing employing a commercially available desktop 3D printer, monolithic construction free of wire-bonded interconnections, and simplicity, indicating its potential for flow monitoring and condition-based maintenance systems aboard vessels as well as in a wide range of industrial sectors. We should note that the present characterisation was performed under laboratory conditions employing a single prototype per design stage; the effects of humidity, salt exposure, vibration, temperature cycling, and material-batch variability remain to be assessed prior to shipboard deployment. Full article

Wellbore fluid flow and heat transfer are strongly coupled during drilling and well construction, where temperature, pressure, rheology, gas behavior, transient operations, and cementing displacement jointly affect pressure-window control and wellbore safety. This review synthesizes advances in coupled wellbore thermal–hydraulic numerical simulation, emphasizing governing equations, discretization strategies, coupling algorithms, rheology and turbulence closures, verification and validation, computational efficiency, uncertainty quantification, and AI-assisted deployment. A bibliometric-guided critical review was conducted using an 841-record Web of Science corpus, 79 screened technical records, 86 screened OnePetro field-facing records, and representative prior reviews. CiteSpace was used to identify knowledge structure and thematic evolution, while screened records were coded by governing physics, numerical method, closure assumption, model output, validation evidence, and deployment relevance. The literature is organized into five model families: wellbore temperature and heat transfer; annular non-Newtonian flow, rheology, turbulence, and CFD; pressure-window and transient hydraulics; cementing displacement and well-construction flow; and AI-assisted calibration and deployment. The synthesis shows that field-deployable simulation requires consistent state variables, transparent closure hierarchies, benchmark validation, uncertainty reporting, CFD-to-well-scale transfer, reduced-order implementation, and physics-constrained AI updating. Full article

Silicon carbide (SiC) has high thermal conductivity and thermal stability; however, its high hardness and brittleness make the fabrication of three-dimensional (3D) SiC microstructures—particularly those intended for thermal management of power devices—highly challenging. Because SiC exhibits strong absorption in the ultraviolet (UV) spectral range, this study conducted UV nanosecond laser irradiation to perform dry, direct-write processing on SiC, with material removal achieved through vaporization. It established an optimization workflow covering processes from the selection of planar processing parameters to the fabrication of 3D micropillar arrays with high surface quality and geometric fidelity. The key process variables were the pulse repetition frequency, nominal laser power, number of repeated scans per layer, and number of Z-direction focal shifts between layers. The micropillar arrays fabricated using the proposed approach were characterized in terms of their total material removal depth, sidewall verticality, and top-surface roughness. The results indicated that processing with a high repetition frequency resulted in favorable sidewall verticality; however, the pillar top surfaces were susceptible to high roughness resulting from spatter and melt backfilling. To address this problem, a strategy involving the fabrication of fewer shifting layers and the use of more scan repetitions per layer was employed. This strategy mitigated cumulative defocus errors, increased the total material removal depth, and achieved a suitable balance among removal depth, sidewall verticality, and top-surface roughness. Overall, this study provides practical guidelines for the direct-write 3D microstructuring of hard materials such as SiC. These guidelines have potential applications in the rapid fabrication of chip-level heat dissipation microstructures. They can reduce process complexity and manufacturing cost while improving design flexibility for 3D thermal architectures. 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

This study develops a MATLAB-based (MathWorks, Natick, MA, USA; version R2024b) first-order probabilistic screening framework for the Shenhu gas hydrate production area, northern South China Sea, to separate the roles of bottom-water warming, geothermal and fluid perturbation, hydrate saturation, excess pore pressure, and slope geometry. The framework integrates methane hydrate phase equilibrium, geothermal profiles, transient heat diffusion, base of gas hydrate stability zone (BGHSZ) migration, conceptual reservoir phase layering, and infinite-slope factor-of-safety (FoS) analysis. The modeled present-day BGHSZ (~271 mbsf) is broadly consistent with reported bottom-simulating-reflector depths. At the baseline thermal diffusivity, conductive potential dissociation thickness stays below 4 m even for +3.0 °C over 1000 years; across the full tested diffusivity–warming–time matrix it ranges 0–19.5 m; geological tests, reported as equilibrium BGHSZ offsets, give larger responses. Monte Carlo analysis under three parallel slope-angle assumptions shows that absolute FoS depends strongly on the slope distribution. Conductive warming reduces the median FoS by about 5.5%, with about 9% of realizations exceeding a 10% reduction, yet low-FoS outcomes remain absent within the tested ranges. Within the adopted parameterization, modeled FoS variability is controlled primarily by slope angle, friction angle, and the prescribed excess pore-pressure ratio, while conductive thermal forcing produces a comparatively modest reduction in relative stability margin. Full article

Inorganic thermal-insulation mortars can effectively reduce the energy consumption and carbon emissions of both existing and new buildings while maintaining the thermal stability of building envelopes. Compared with conventional mortars, these materials exhibit more pronounced multiscale coupling during curing, and their microstructural evolution and macroscopic properties are highly sensitive to environmental variables, particularly temperature, humidity, and ionic concentration. This review systematically summarizes the effects of high-temperature curing, high-humidity curing, artificially introduced ions, and special curing regimes on the mechanical properties, durability, thermal conductivity, and fire resistance of inorganic thermal-insulation mortars. The reviewed studies indicate that hydration, geopolymerization, and CO₂-curing reactions can all promote microstructural densification and thus enhance mechanical performance and durability. Elevated temperature and humidity generally accelerate reaction kinetics, intensify internal hydration, and facilitate the generation and deposition of gel products, thereby refining the pore structure and improving strength development. However, the same densification process may also increase the continuity of the solid phase and form more effective heat-transfer pathways, which is unfavorable for thermal-insulation performance. Mildly alkaline curing environments can further stimulate binder reactions and improve matrix compactness, although excessive ionic activity may negatively affect pore stability and long-term performance. Among the coupled curing conditions, wet–dry cycling appears to provide a more favorable balance between mechanical-property development and pore-structure preservation, because periodic humidity gradients can enhance strength formation, stabilize the interfacial transition zone, and reduce cracking sensitivity. Overall, the effect of curing on inorganic thermal-insulation mortars is governed by the competition and balance between reaction enhancement, pore-structure evolution, and interfacial stabilization. Future curing design should therefore focus on system-dependent optimization to achieve a rational balance among mechanical performance, thermal insulation, and fire resistance. Full article

Biomass torrefaction represents a highly promising thermochemical pathway for upgrading low-density agricultural residues into high-value solid biofuels. However, optimizing reactor operations requires resolving the conflict between product energy enrichment and mass loss under transient heat transfer limitations. In this work, a transient kinetics-coupled Pareto optimization and techno-economic framework is developed for the torrefaction of rice husk residues (Oryza sativa), with pine wood (Pinus sp.) as a validation reference. The framework connects a transient 1D radial finite-difference heat transfer model in a cylindrical particle to a two-stage sequential chemical kinetics scheme, which was successfully calibrated against experimental thermogravimetric analysis (TGA) data. The physical model outputs (instantaneous species concentrations, temperature profiles, and process thermal demand) are dynamically coupled to an economic module to calculate the Levelized Cost of Torrefaction (LCOT). A grid sweep with Pareto non-dominance filtering is conducted on the active torrefaction design space (using a product quality constraint $Y_{BT}\le 0.96$ to avoid degenerate zero-conversion limits) to identify the Pareto frontier that minimizes LCOT while maximizing the efficiency index ($\eta$). To evaluate the financial and technical stability of the Pareto operating point for rice husk (523 K, 30 min), a global sensitivity and uncertainty analysis (GSA) is executed using 250 Latin Hypercube Sampling (LHS) Monte Carlo simulations coupled with Standardized Regression Coefficients (SRCs). The results show a baseline LCOT of 6.49 USD/GJ for rice husk at its 1 dry t/h pilot Pareto knee point (523 K, 30 min), which is projected to decrease to 4.12 USD/GJ under an industrial-scale techno-economic scenario (50 dry t/h). Under uncertainty, LCOT displays a mean value of $6.486\pm 0.565$ USD/GJ (95% CI: $5.517$–$7.644$ USD/GJ), which is heavily dominated by the raw feedstock acquisition cost ($\beta =0.7430$, $p<0.001$) and CAPEX contingency multiplier ($\beta =0.6129$). The efficiency index exhibited limited variability (mean $91.40\%\pm 0.96\%$, 95% CI: $89.80\%$–$93.26\%$), governed primarily by the particle diameter $d_p$ ($\beta =0.7828$) and secondary convective heat transfer coefficient h ($\beta =-0.5929$, $p<0.001$). This work successfully demonstrates that coupling transient transport phenomena to a techno-economic cash-flow layer provides a physics-informed framework for techno-economic evaluation and scale-up of thermochemical bioreactors. Full article

Bio-based packaging is receiving increasing attention due to the environmental impact of fossil-based plastics. However, its practical implementation requires further evidence on material processing and functional performance. This study evaluated the thermal properties of expanded polylactic acid (E-PLA) prototypes blended with raw, minimally processed agroforestry residues. Specifically, spruce bark and grape stalks were used as waste wood fibers. This study focused primarily on the thermal characterization of the materials by measuring thermal conductivity and resistance. To evaluate the distribution of the two fractions (polymer and fibrous), samples were created with various volumetric ratios between the parts. Simultaneous pressure and microwave heating of the sample were used to stabilize the material. To characterize the raw materials used in this study, bulk density and moisture content were measured. To characterize the mixed materials samples, thermal conductivity and resistance, bulk density, and pressure were measured. To investigate the variables that influence thermal characteristics, statistical analyses such as regression models, ANCOVA, and Spearman correlation were applied. These analyses showed that increasing the biofiber content significantly reduced thermal resistance and increased thermal conductivity. However, negligible effects were observed for the type of fiber used and the duration of the heat treatment. These results describe the thermal properties of blends containing E-PLA and agroforestry residues. The results also show a marked effect of the biofiber content on thermal performance. This study does not provide a comprehensive characterization of the new materials, as it focuses on the prototyping methodology and the laboratory-scale production feasibility of E-PLA/agroforestry-residue prototypes. Full article

Film mulching can promote maize canopy development by altering soil thermal conditions. However, commonly used air-temperature-based growing degree days (GDDs_air) may not adequately reflect mulch-induced soil warming or the effects of biodegradable film degradation on leaf area index (LAI) dynamics. To improve unified simulation of maize LAI under different film mulching conditions, field experiments were conducted in 2023 and 2024. Five treatments were established: 0.006, 0.008 and 0.010 mm biodegradable films (DM1, DM2 and DM3, respectively), a 0.010 mm conventional plastic film (PM), and a no-mulching control (CK). The compensation of increased soil temperature for air-temperature-based thermal accumulation during early maize growth was quantified. Modified Logistic LAI models were then developed using days after emergence (DAEs), GDDs_air, soil-temperature-compensated growing degree days (GDDs_stc), and normalized GDDs_stc (NGDDs_stc) as driving variables. The models were calibrated with observations from 2023 and independently validated with observations from 2024. The compensation effect acted through mulch-induced increases in 0–10 cm soil temperature during early maize growth and was stronger at the seedling stage than at the jointing stage. Compared with DM1 and DM2, daily compensation values were higher by 0.25–0.78 °C under DM3 and by 0.26–0.76 °C under PM. Independent validation showed that the GDDs_stc-driven model had lower prediction error than the DAEs- and GDDs_air-driven models. The NGDDs_stc-driven model performed best; its RMSE values were 17.61%, 15.17% and 10.91% lower than those of the DAEs-, GDDs_air- and GDDs_stc-driven models, respectively. These results indicate that incorporating mulch-induced soil temperature compensation into the thermal time scale can more accurately represent maize canopy development under film mulching conditions. Full article