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29 pages, 5079 KB  
Article
Scaling Behavior of Sloshing Impact Pressures Based on Event Distribution and Regime Classification
by Hyung-Min Baek, Jun Kim, Yeonkang Choi, Jimin Hyun, Sung-chul Shin, Yun-ho Shin, Young-Myung Choi, Eun Jung Chae, Hongrae Park and Eun Soo Kim
J. Mar. Sci. Eng. 2026, 14(10), 915; https://doi.org/10.3390/jmse14100915 - 15 May 2026
Viewed by 254
Abstract
Sloshing in partially filled tanks generates significant impact pressures that threaten the structural integrity of LNG cargo containment systems, and accurate scaling of these impacts remains a critical issue. Although Froude-based scaling has been widely applied, its validity may be limited under conditions [...] Read more.
Sloshing in partially filled tanks generates significant impact pressures that threaten the structural integrity of LNG cargo containment systems, and accurate scaling of these impacts remains a critical issue. Although Froude-based scaling has been widely applied, its validity may be limited under conditions where multiple impact mechanisms coexist. In this study, sloshing impact pressures measured across different scales were analyzed based on individual impact events. Distribution-based representative metrics, including mean and upper-percentile values, were introduced, and scale dependency was quantified using a power-law relationship. The results show that under low filling conditions, impact responses exhibit relatively consistent distributions, and gravity-based scaling yields nearly scale-independent results. In contrast, high filling conditions lead to increased variability and a pronounced expansion of the upper tail, resulting in stronger scale dependency, particularly for high-intensity events. The increase in the power-law exponent indicates that extreme impacts are more sensitive to scale variation. These findings demonstrate that sloshing impact scaling is governed not by a uniform change in pressure magnitude, but by a redistribution of impact intensity across events. Consequently, reliable scaling requires consideration of both distribution characteristics and underlying impact mechanisms. Full article
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20 pages, 2019 KB  
Article
Study of Dangling Bond States in Magnetron-Sputtered a-Si Thin Films via Parametrization Using a Single UV–Vis–NIR Transmittance Spectrum
by Dorian Minkov, George Angelov, Dimitar Nikolov, Rostislav Rusev, Eduardo Blanco, Susana Fernandez, Manuel Ballester and Emilio Marquez
Molecules 2026, 31(9), 1469; https://doi.org/10.3390/molecules31091469 - 28 Apr 2026
Viewed by 482
Abstract
While both Urbach tails and dangling bonds are known to be present in a-Si films, the current literature lacks parametrization that simultaneously accounts for both types of defects using only transmittance spectra, reflectance spectra, or spectroscopic ellipsometry. To address this issue, we performed [...] Read more.
While both Urbach tails and dangling bonds are known to be present in a-Si films, the current literature lacks parametrization that simultaneously accounts for both types of defects using only transmittance spectra, reflectance spectra, or spectroscopic ellipsometry. To address this issue, we performed parametrizations of three magnetron-sputtered a-Si thin films deposited on glass substrates at different low pressures of argon gas, using only their measured UV–Vis–NIR transmittance spectra T(λ = [300, 2500] nm) and different dispersion models. We preprocessed T(λ) by suppressing both general and bandpass noise to yield the spectrum Td(λ). The films were parametrized from Td(λ) using two versions of the Tauc–Lorentz–Urbach dispersion model and the universal dispersion model (UDM) of Franta. The most accurate parametrization was achieved employing UDM including Urbach tail and three subgap oscillators. JDOS and the dielectric function ε(E) were computed by this UDM, and it was concluded that these three oscillators correspond to electron transitions via two bands of dangling bonds. The respective DOS is similar to the DOS previously reported for a-Si:H, but not to a-Si, indicating a relatively low density of dangling bonds in our a-Si films. Record low parametrization errors are achieved, which confirms the accuracy of these results. Full article
(This article belongs to the Section Materials Chemistry)
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18 pages, 5694 KB  
Article
Preference-Conditioned MADDPG for Risk-Aware Multi-Agent Siting of Urban EV Charging Stations Under Coupled Traffic-Distribution Constraints
by Yifei Qi and Bo Wang
Mathematics 2026, 14(9), 1464; https://doi.org/10.3390/math14091464 - 27 Apr 2026
Viewed by 386
Abstract
The public deployment of electric vehicle charging stations must simultaneously balance construction economics, user accessibility, queueing pressure, feeder security, tail risk under demand uncertainty, and spatial fairness. These criteria are strongly coupled, yet most existing studies either rely on static optimization with limited [...] Read more.
The public deployment of electric vehicle charging stations must simultaneously balance construction economics, user accessibility, queueing pressure, feeder security, tail risk under demand uncertainty, and spatial fairness. These criteria are strongly coupled, yet most existing studies either rely on static optimization with limited behavioral realism or use multi-agent reinforcement learning for short-term charging operation rather than for long-term siting. This paper proposes a preference-conditioned multi-agent deep deterministic policy gradient (PC-MADDPG) framework for the urban charging station siting problem in a coupled traffic–distribution environment. Candidate charging sites are modeled as cooperative agents under centralized training and decentralized execution. Each agent outputs a continuous pile-allocation action, which is repaired into an integer expansion plan under a budget constraint. The environment evaluates each plan through attraction-based demand assignment, queue approximation, LinDistFlow-style feeder analysis, and a six-objective performance vector, including annual net cost, travel burden, service inconvenience, grid penalty, CVaR of unmet charging demand, and equity loss. On a reproducible benchmark with 12 demand zones, 10 candidate sites, an 11-bus radial feeder, and 16 stochastic daily scenarios, the proposed framework generates a non-dominated archive with 42 unique feasible plans. A representative PC-MADDPG solution opens 5 of 10 candidate sites and installs 20 fast-charging piles, achieving 99.88% mean demand coverage with an annual profit of 2.083 M$ and a maximum line utilization of 0.999. Relative to the NoGrid ablation, the selected full model reduces grid penalty by 23.87% and equity Gini by 51.08%, with only a 0.35% profit concession. Relative to the NoRisk ablation, the CVaR of unmet demand is lowered by 69.70%. Compared with a demand-greedy baseline, the proposed method reduces grid penalty by 11.72% and equity Gini by 25.19% while preserving similar demand coverage. These results provide proof-of-concept evidence, on a reproducible coupled benchmark, that preference-conditioned multi-agent learning can serve as a practical many-objective siting engine for charging-infrastructure planning when coupled traffic and feeder constraints are explicitly modeled. Full article
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22 pages, 2220 KB  
Article
A Large Lizard in a Small Islet: Abundance, Body Growth, and Diet of Podarcis pityusensis from Es Vaixell (Balearic Islands, Spain)
by Valentín Pérez-Mellado and Ana Pérez-Cembranos
Animals 2026, 16(9), 1314; https://doi.org/10.3390/ani16091314 - 24 Apr 2026
Viewed by 359
Abstract
The islet of Vaixell, off the west coast of Ibiza (Balearic Islands, Spain), is home to a native population of the Pityusic wall lizard, Podarcis pityusensis, with the largest body size recorded for the species. These lizards live in extreme environmental conditions [...] Read more.
The islet of Vaixell, off the west coast of Ibiza (Balearic Islands, Spain), is home to a native population of the Pityusic wall lizard, Podarcis pityusensis, with the largest body size recorded for the species. These lizards live in extreme environmental conditions on an islet with a small surface area covered by very sparse vegetation. The sex ratio is balanced, and a very high incidence of missing toes and autotomized tails is observed, indicating strong intraspecific competition involving both males and females. The body growth rate, adjusted using the Gompertz model, is intense and, apparently, juvenile lizards quickly reach relatively large body sizes. This fast body growth is probably a strategy against predation pressure from conspecifics. In P. pityusensis from Vaixell, the peak growth acceleration is prenatal and practically coincides with the moment of hatching. The diet consists mainly of aggregated prey, such as ants, with the inclusion of marine subsidies, such as halophyllous and littoral isopods, and a lower consumption of plant matter compared to other insular populations of lizards from the Balearic Islands. The lizards of Vaixell are an excellent example of the adaptive response of a lacertid lizard to the extreme conditions on the small coastal islets of the Mediterranean, with very small available areas, high population density, but a small population size, of about 50 to 100 lizards, which also reach a remarkable longevity. Full article
(This article belongs to the Section Herpetology)
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22 pages, 19614 KB  
Article
Where Himalayan Forests Are More (or Less) Complex than Their Height Suggests: An Uncertainty-Aware GEDI Indicator for Monitoring and Management
by Niti B. Mishra and Gargi Chaudhuri
Remote Sens. 2026, 18(8), 1222; https://doi.org/10.3390/rs18081222 - 17 Apr 2026
Viewed by 421
Abstract
Forest structural complexity underpins habitat quality, microclimate buffering, and resilience, yet it remains poorly characterized across the Hindu Kush Himalaya (HKH) where field inventories and airborne LiDAR are difficult to scale across rugged terrain. Conservation planning and protected-area evaluation in the HKH therefore [...] Read more.
Forest structural complexity underpins habitat quality, microclimate buffering, and resilience, yet it remains poorly characterized across the Hindu Kush Himalaya (HKH) where field inventories and airborne LiDAR are difficult to scale across rugged terrain. Conservation planning and protected-area evaluation in the HKH therefore often rely on canopy height or cover proxies that do not directly represent vertical structural organization. Here we develop a repeatable, uncertainty-aware indicator of forest structural complexity from GEDI waveform LiDAR using the Waveform Structural Complexity Index (WSCI) and its prediction intervals. We first define a conservative analysis footprint (“trustable pixels”) by combining a woody-vegetation screen with minimum GEDI sampling support and canopy-stature plausibility, and by excluding the highest-uncertainty tail using a relative prediction-interval criterion. To separate complexity from canopy height, we model the HKH-wide expected WSCI–RH98 relationship and map height-normalized excess complexity (observed minus expected), identifying structural complexity hotspots and coldspots as the upper and lower tails of the excess distribution. Anomaly patterns are strongly organized along elevation and treeline-relevant belts and show coherent departures among ecoregions that persist after stratified adjustment for elevation and mean annual precipitation, indicating additional controls beyond broad environmental gradients. Protected areas exhibit systematically lower hotspot prevalence than surrounding landscapes, and within-elevation comparisons suggest this association is not explained by elevation alone, highlighting the need to interpret protected-area signals in the context of placement and land-use pressure. Overall, the anomaly atlas provides an operational indicator framework to stratify monitoring, prioritize field validation, and support the landscape-scale assessment of structural conditions beyond canopy height across one of the world’s most critical mountain forest systems. Full article
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15 pages, 4921 KB  
Article
Evaluation of Hypoxia Tolerance and Cloning-Expression Analysis of Related Genes in Hybrid Fish Derived from Megalobrama amblycephala × Xenocypris davidi Bleeker
by Zhong Tang, Xinxin Yu, Xin Chen, Junwen Liang, Yangyang Tu, Zhifeng Zhou, Faxian Yu, Chun Zhang, Siyu Fan and Min Tao
Fishes 2026, 11(4), 233; https://doi.org/10.3390/fishes11040233 - 15 Apr 2026
Viewed by 384
Abstract
The diploid distant hybrid (2nBY) derived from female blunt snout bream (Megalobrama amblycephal, BSB) × male Bleeker’s yellow tail (Xenocypris davidi Bleeker, YT). To investigate the hypoxia tolerance and the regulatory mechanisms of hypoxia-inducible factor-1α/2α (hif-1α/) [...] Read more.
The diploid distant hybrid (2nBY) derived from female blunt snout bream (Megalobrama amblycephal, BSB) × male Bleeker’s yellow tail (Xenocypris davidi Bleeker, YT). To investigate the hypoxia tolerance and the regulatory mechanisms of hypoxia-inducible factor-1α/2α (hif-1α/) in 2nBY, BSB, and YT, experiments consisting of 24 h of hypoxia treatment (DO = 2.0 ± 0.1 mg/L) followed by 6 h of reoxygenation were conducted. The loss of equilibrium critical oxygen pressure (LOEcrit), gill tissue structure, and antioxidant indices, as well as the full-length sequences and expression of hif-1α/ in 2nBY, BSB, and YT, were compared. The results showed that the LOEcrit value of 2nBY was significantly lower than that of BSB but higher than that of YT (p < 0.05). After hypoxia treatment, the changes in gill tissue structure and antioxidant indices of 2nBY were less obvious than those of BSB, and the recovery rate was faster after reoxygenation. Sequence analysis revealed high similarity of hif-1α/ between YT and 2nBY. After hypoxia treatment, hif-1α/ were upregulated in the liver but showed distinct gill expression among the three groups. Their gill expression differences may contribute to varied hypoxic tolerance. Distant hybridization between BSB and YT successfully generated hybrid offspring with enhanced hypoxia tolerance relative to BSB. These results provide theoretical and technical support for the breeding of a new hypoxia-tolerant germplasm resource of bream. Full article
(This article belongs to the Special Issue Physiological and Behavioral Studies in Aquaculture)
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29 pages, 5152 KB  
Article
Impact of Neural Network Initialisation Seed and Architecture on Accuracy, Generalisation and Generative Consistency in Data-Driven Internal Combustion Engine Modelling
by Arturas Gulevskis, Redha Benhadj-Djilali and Konstantin Volkov
Computers 2026, 15(3), 194; https://doi.org/10.3390/computers15030194 - 17 Mar 2026
Viewed by 505
Abstract
Artificial neural networks (ANNs) are widely used to approximate nonlinear mappings, yet their ability to capture thermodynamic behaviour in dynamic physical systems remains insufficiently characterised. This study investigates how representational capacity influences surrogate modelling accuracy for a crank-angle-resolved internal combustion engine (ICE) simulation [...] Read more.
Artificial neural networks (ANNs) are widely used to approximate nonlinear mappings, yet their ability to capture thermodynamic behaviour in dynamic physical systems remains insufficiently characterised. This study investigates how representational capacity influences surrogate modelling accuracy for a crank-angle-resolved internal combustion engine (ICE) simulation with a maximum dynamic state dimension of six. Two feedforward ANN configurations are evaluated: a low-capacity 5–5 architecture containing 84 trainable parameters and a high-capacity 25–25–25 architecture containing 1554 parameters (18.5× larger). Both networks approximate the nonlinear mapping from five embedded operating parameters to four peak thermodynamic outputs (maximum pressure, pressure phasing, maximum temperature, and temperature phasing). Evaluation across 53,178 operating points demonstrates that the high-capacity configuration reduces root mean squared error by factors of 30–50× relative to the low-capacity network, decreasing peak temperature error from 17.68 K to 0.36 K and peak pressure error from 0.116 MPa to 0.0025 MPa. Although both models achieve coefficients of determination exceeding 0.99, the low-capacity network exhibits heavy-tailed residual distributions and regime-dependent error amplification, whereas the high-capacity model reduces both central dispersion and extreme-case error. These results demonstrate that high correlation alone does not guarantee engineering reliability in nonlinear thermodynamic systems. Distribution-level analysis, including percentile and extreme-case characterisation, is required to evaluate engineering robustness. The findings provide a quantitative framework linking ANN capacity, nonlinear dynamic system representation, and predictive robustness. Full article
(This article belongs to the Special Issue Deep Learning and Explainable Artificial Intelligence (2nd Edition))
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19 pages, 658 KB  
Article
Cohesion as Concentration: Exclusion-Driven Fragility in Financial Organizations
by Foong Soon Cheong
J. Risk Financial Manag. 2026, 19(3), 220; https://doi.org/10.3390/jrfm19030220 - 16 Mar 2026
Viewed by 551
Abstract
Financial crises repeatedly reveal organizations that appear internally aligned while failing to recognize accumulating tail risks. This paper argues that cohesion is observationally ambiguous. It can arise from information integration, in which heterogeneous inputs are debated and synthesized, or from exclusion, in which [...] Read more.
Financial crises repeatedly reveal organizations that appear internally aligned while failing to recognize accumulating tail risks. This paper argues that cohesion is observationally ambiguous. It can arise from information integration, in which heterogeneous inputs are debated and synthesized, or from exclusion, in which variance is removed through conformity pressure, gatekeeping, and intolerance of dissent. This distinction is formalized using a signal aggregation model in which an organization maintains an anchor belief and achieves agreement through two exclusion channels: report shrinkage toward the anchor and a tolerance rule that discards reports deviating beyond a threshold. Relative to a full inclusion benchmark, exclusion based cohesion jointly produces state contingent bias that is small in normal regimes but grows sharply under displacement, illusory precision in which observed disagreement falls as tail regime estimation error rises, effective concentration of decision inputs below the nominal participant count, and, when the anchor updates from filtered aggregates, dynamic lock in with delayed regime recognition and abrupt correction. External inputs that bypass internal filtering shorten recognition delays. The model yields testable governance diagnostics linking latent fragility to observable patterns in recorded dissent, anonymous to formal voting gaps, scenario set diversity, pipeline and method concentration, and anchor lag. The central implication is that governance systems should treat low internal conflict and unanimity as potentially diagnostic of variance depletion and should monitor whether heterogeneity is integrated or excluded before stress reveals the difference. Full article
(This article belongs to the Section Risk)
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36 pages, 5029 KB  
Article
Option-C Verified Semantic Digital Twins for Decarbonized, Pressure-Reliable Central Business District Hospitals
by Zhe Wei
Buildings 2026, 16(6), 1096; https://doi.org/10.3390/buildings16061096 - 10 Mar 2026
Viewed by 499
Abstract
Central business district (CBD) hospitals must sustain reliable pressure relationships in critical rooms while reducing whole-facility carbon under tight space and disruption constraints. We developed an ontology-grounded semantic digital twin that normalizes building automation system (BAS) and building management system (BMS) telemetry into [...] Read more.
Central business district (CBD) hospitals must sustain reliable pressure relationships in critical rooms while reducing whole-facility carbon under tight space and disruption constraints. We developed an ontology-grounded semantic digital twin that normalizes building automation system (BAS) and building management system (BMS) telemetry into a unified semantic store consistent with Brick Schema, enabling portable asset discovery via query and thereby supporting forecasting, anomaly detection, and multi-objective optimization without dependence on vendor point naming conventions. Whole-facility impacts were verified using International Performance Measurement and Verification Protocol Option C–style measurement and verification with an S0-calibrated baseline model and residual-based savings attribution. Relative to the baseline (S0), the intervention (S3) produced a step increase in the critical-room pressure-compliance pass rate, tighter room-to-corridor differential-pressure (ΔP) control across airborne infection isolation and open room strata, and intent-aligned ventilation delivery (air changes per hour ratio distribution concentrated near unity; p < 0.05 where letter groups differ). Operational-state discrimination improved (AUC 0.649→0.696) and issue-resolution times shortened (left-shifted cumulative distribution function), indicating reduced service burden. Option C verification showed energy residuals shifting negative under S3, consistent with net savings versus baseline expectations. Across progressive maturity (S0→S3), time-to-value and burden fractions decreased, carbon intensity (tCO2e m−2) decreased, long-tail exposure compressed (log-scale horizon), and composite performance indices increased (p < 0.05). These results demonstrate a verifiable pathway to pressure-reliable, decarbonized hospital operations at the whole-facility boundary while making the semantic layer’s utility explicit through query-driven, ontology-grounded asset discovery. We present an IPMVP Option-C–verifiable semantic digital-twin governance framework that links audited operational evidence (telemetry → actions → verification) to whole-facility energy and carbon outcomes while maintaining critical-room pressure-relationship reliability. Optimization benchmarking (including quantum annealing) is used as supporting decision-support evaluation, rather than as the central contribution. Full article
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31 pages, 2803 KB  
Article
Kinglet in the Poultry Court of Russia: Whole-Genome Insights into Ancestry, Genetic Variability, Selection Footprints and Candidate Genes in a Unique Local Chicken Breed Relative to Other Bantam/Dwarf Breeds
by Natalia V. Dementieva, Yuri S. Shcherbakov, Anatoli B. Vakhrameev and Michael N. Romanov
Animals 2026, 16(4), 642; https://doi.org/10.3390/ani16040642 - 17 Feb 2026
Viewed by 660
Abstract
Assessing genetic diversity in various native poultry breeds, including bantam/dwarf ones, is instrumental for their conservation as genetic resources, identifying their specific genetic features, and exploring the history of their genetic divergence. Rare chicken breeds are usually carriers of peculiar phenotypic traits, including [...] Read more.
Assessing genetic diversity in various native poultry breeds, including bantam/dwarf ones, is instrumental for their conservation as genetic resources, identifying their specific genetic features, and exploring the history of their genetic divergence. Rare chicken breeds are usually carriers of peculiar phenotypic traits, including adaptations to local conditions, disease resistance, and unique performance features. Here, we report for the first time SNP-based genetic characterization of the Russian Korolyok, translated as “kinglet,” relative to five other dwarf/small breeds: Cochin Bantam, Hamburg Bantam Silver Spangled, Polish White-crested Black, Red White-tailed Dwarf and Silkie White. We estimated phenotypes, heterozygosity, inbreeding, effective population size, and runs of homozygosity (ROHs). Some breeds had higher genetic diversity and others showed elevated inbreeding rates in their genomes. With lower effective population sizes (both presently and in the past), rare breeds came from a limited number of ancestors or were under strong selection pressure over many generations. Within 22 ROHs, we identified 26 prioritized candidate genes (GRB10, RPRD1A, APOOL, EAF2, SEMA5, HACD2, GALANT1, DACH2, CHM, POF1B, HDX, SLC15A2, PDIA5, SEC22, NR2F2, ARRDC4, IGF1R, SYNM, TMEM263, etc.). Our data offer whole-genome insights into genetic variability, history, phylogeny, selective sweeps, and candidate genes of a distinct indigenous Russian chicken breed and other bantam/dwarf breeds. Full article
(This article belongs to the Special Issue Genetic Diversity and Conservation of Local Poultry Breeds)
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20 pages, 3926 KB  
Article
Hydrodynamic Performance of Cubic Artificial Reefs During Deployment Process Based on Smoothed Particle Hydrodynamics
by Wenhua Chu, Shijing Lu, Zijing Zhao, Xinyang Zhang and Yulei Huang
Fishes 2026, 11(1), 59; https://doi.org/10.3390/fishes11010059 - 16 Jan 2026
Viewed by 597
Abstract
Currently, research on the hydrodynamic characteristics of artificial reef deployment still faces challenges such as insufficient environmental coupling, but accurate simulation of the deployment process holds significant engineering importance for optimizing deployment efficiency and ensuring reef stability. This study employs the Smoothed Particle [...] Read more.
Currently, research on the hydrodynamic characteristics of artificial reef deployment still faces challenges such as insufficient environmental coupling, but accurate simulation of the deployment process holds significant engineering importance for optimizing deployment efficiency and ensuring reef stability. This study employs the Smoothed Particle Hydrodynamics (SPH) method to establish a 3D numerical model, focusing on the influence of key parameters—inflow velocity and water entry angle—on the hydrodynamic characteristics of cubic artificial reef deployment. The results indicate that under flow velocities of 0.4–0.5 m/s, pressure fluctuations are relatively minor, with peak pressure gradients below 15 kPa/m, exhibiting a gradual trend, while particle concentration remains high, and drag gradually increases. At flow velocities of 0.6–0.8 m/s, the maximum pressure at the bottom reaches up to 35 kPa, with low-pressure areas at the tail dropping to −10 kPa; particle concentration decreases compared to conditions at 0.4–0.5 m/s; settling time extends from 8.4 s to 12 s, representing a 42% increase. Under different water entry angles, drag varies nonlinearly with the angle, reaching its maximum at 20° and its minimum at 25°, with a reduction of approximately 47% compared to the maximum. The anti-sliding safety factor and anti-overturning safety factor are used to assess the stability of the cubic reef placed on the seabed. Across different inflow velocities, the anti-sliding safety factor of the cubic artificial reef significantly exceeds 1.2, whereas the anti-overturning safety factor is below 1.2 at 0.4 m/s but exceeds 1.2 at velocities of 0.5 m/s and above, indicating that the reef maintains stability under the majority of these flow conditions. Our findings provide a scientific basis for the deployment process, site selection, and geometric design of cubic artificial reefs, offering valuable insights for the precise deployment and structural optimization of artificial reefs in marine ranching construction. Full article
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17 pages, 858 KB  
Article
Integrated PSA Hydrogen Purification, Amine CO2 Capture, and Underground Storage: Mass–Energy Balance and Cost Analysis
by Ersin Üresin
Processes 2026, 14(2), 319; https://doi.org/10.3390/pr14020319 - 16 Jan 2026
Cited by 1 | Viewed by 1448
Abstract
Although technologies used in non-fossil methane and fossil resources to produce blue hydrogen are relatively mature, a system-integrated approach to reference system (RS)-based purification of H2, CO2 capture and storage, and UHS is relatively unexplored and requires research to fill [...] Read more.
Although technologies used in non-fossil methane and fossil resources to produce blue hydrogen are relatively mature, a system-integrated approach to reference system (RS)-based purification of H2, CO2 capture and storage, and UHS is relatively unexplored and requires research to fill gaps in the literature regarding balanced permutations and geological viability for net-zero requirements. This research proposes a system-integrated process for H2 production through a PSA-based purification technique coupled with amine-based CO2 capture and underground hydrogen storage (UHS). The intellectual novelty of the research is its first quantitative treatment of synergistic effects such as heat recovery and pressure-matching across units. Additionally, a site separation technique is applied, where H2 and CO2 reservoirs are selected based on the permeability of rock formations and fluids. On a research methodology front, a base case of a steam methane reforming process with the production of 99.99% pure H2 at a production rate of 5932 kg/h is modeled and simulated using Aspen Plus™ to create a balanced permutation of mass and energy across units. As per the CO2 capture requirements of this research, a capture of 90% of CO2 is accomplished from the production of 755 t/d CO2 within the model. The compressed CO2 is permanently stored at specifically identified rock strata separated from storage reservoirs of H2 to avoid empirically identified hazards of rock–fluid interaction at high temperatures and pressures. The lean amine cooling of CO2 to 60 °C and elimination of tail-gas recompression simultaneously provides 5.4 MWth of recovered heat. The integrated design achieves a net primary energy penalty of 18% of hydrogen’s LHV, down from ~25% in a standalone configuration. This corresponds to an energy saving of 8–12 MW, or approximately 15–18% of the primary energy demand. The research computes a production cost of H2 of 0.98 USD per kg of H2 within a production atmosphere of a commercialized WGS and non-fossil methane-based production of H2. Additionally, a sensitivity analysis of ±23% of the energy requirements of the reference system shows no marked sensitivity within a production atmosphere of a commercially available WGS process. Full article
(This article belongs to the Special Issue Hydrogen–Carbon Storage Technology and Optimization)
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17 pages, 3983 KB  
Article
Reference Static Pressure Effect on Fluctuating Wind Pressure on Roofs of Low-Rise Buildings in Open-Circuit Wind Tunnels
by Mengchang Yang, Enguang Wang and Il-Seung Yang
Buildings 2025, 15(23), 4208; https://doi.org/10.3390/buildings15234208 - 21 Nov 2025
Viewed by 615
Abstract
The structural characteristics of open-circuit wind tunnels result in internal static pressure instability, which can affect the accuracy of wind pressure coefficient measurements on rigid models of low-rise buildings. To address this issue, a Pitot tube and an ESP electronic pressure scanning system [...] Read more.
The structural characteristics of open-circuit wind tunnels result in internal static pressure instability, which can affect the accuracy of wind pressure coefficient measurements on rigid models of low-rise buildings. To address this issue, a Pitot tube and an ESP electronic pressure scanning system were used to collect data on reference static pressure variation and wind pressure on the roof of a low-rise building under Class B wind terrain and different temperature conditions. The results indicate that the reference static pressure decreases with increasing temperature and is significantly influenced by external airflow disturbances at the beginning of the experiment, and it tends to stabilize approximately 5 min after the wind tunnel is activated. The probability density of reference static pressure under different conditions mostly follows a Gaussian distribution, although a few samples exhibit heavy-tailed or skewed fluctuations. The sliding standard deviation and coefficient of variation of the reference static pressure are both relatively small, but occasional samples show extreme fluctuations. It is recommended to apply filtering techniques or repeated measurements to reduce experimental errors. At a wind direction angle of 0°, the fluctuating wind pressure coefficients on the roof calculated using reference static pressures from different samples exhibit good consistency. The average mean relative error of the fluctuating wind pressure coefficients across roof zones I–VIII was 3.71%, which is within an acceptable range. The research findings provide a useful reference for reducing result errors in wind pressure tests conducted in open-circuit wind tunnels. Full article
(This article belongs to the Section Building Structures)
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29 pages, 3223 KB  
Article
Injectable In Situ Thermoreversible Gel Depot System of Lidocaine Nanoemulsion for Prolonged Anesthetic Activity in Dental and Operative Procedures
by Shery Jacob, Fathima Sheik Kather, Shakta Mani Satyam, Sai H. S. Boddu, Firas Assaf, Tasnem H. Abdelfattah Allam and Anroop B. Nair
Pharmaceutics 2025, 17(10), 1355; https://doi.org/10.3390/pharmaceutics17101355 - 20 Oct 2025
Cited by 2 | Viewed by 2385
Abstract
Background/Objectives: Lidocaine hydrochloride (LD-HCl) is the most commonly used local anesthetic in dentistry, often administered with epinephrine to extend its duration and reduce systemic absorption. However, its relatively short duration of action, the need for repeated injections, and the unpleasant taste may limit [...] Read more.
Background/Objectives: Lidocaine hydrochloride (LD-HCl) is the most commonly used local anesthetic in dentistry, often administered with epinephrine to extend its duration and reduce systemic absorption. However, its relatively short duration of action, the need for repeated injections, and the unpleasant taste may limit patient compliance and procedural efficiency. This study aimed to develop and evaluate a novel injectable nanoemulsion-based in situ gel depot system of LD to provide prolonged anesthetic activity. Methods: LD-loaded nanoemulsions were formulated by high-shear homogenization followed by probe sonication, employing Miglyol 812 N (oil phase), a combination of Tween 80 and soy lecithin (surfactant–co-surfactant), glycerin, and deionized water (aqueous phase). The selected nanoemulsion (S1) was dispersed in a thermoreversible poloxamer solution to form a nanoemulgel. The preparation was evaluated for globule diameter and uniformity, zeta potential, surface morphology, pH, drug content, stability, rheological behavior, injectability, and in vitro drug release. Analgesic efficacy was assessed via tail-flick and thermal paw withdrawal latency tests in Wistar rats. Cardiovascular safety was monitored using non-invasive electrocardiography and blood pressure measurements. Results: The developed nanoemulsions demonstrated a spherical shape, nanometer size (206 nm), high zeta-potential (−66.67 mV) and uniform size distribution, with a polydispersity index of approximately 0.40, while the nanoemulgel demonstrated appropriate thixotropic properties for parenteral administration. In vitro release profiles showed steady LD release (5 h), following the Higuchi model. In vivo studies showed significantly prolonged analgesic effects lasting up to 150 min (2.5 h) compared to standard LD-HCl injection (p < 0.001), with no adverse cardiovascular effects observed. Conclusions: The developed injectable LD in situ nanoemulgel offers a promising, patient-friendly alternative for prolonged anesthetic delivery in dental and operative procedures, potentially reducing the need for repeated injections and enhancing procedural comfort. Full article
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17 pages, 3534 KB  
Article
Lift–Thrust Integrated Ducted-Grid Fusion Configuration Design for a Ducted Fan Tail-Sitter UAV
by Lei Liu and Baigang Mi
Appl. Sci. 2025, 15(14), 7687; https://doi.org/10.3390/app15147687 - 9 Jul 2025
Viewed by 2000
Abstract
A new lift enhancement scheme is designed for the cruise flight process of a tail-sitter UAV (Unmanned Aerial Vehicle), proposing a fusion configuration with embedded grid channels on the duct wall. The low pressure zone at the lip of the duct is induced [...] Read more.
A new lift enhancement scheme is designed for the cruise flight process of a tail-sitter UAV (Unmanned Aerial Vehicle), proposing a fusion configuration with embedded grid channels on the duct wall. The low pressure zone at the lip of the duct is induced to expand through the grid channels, forming a significant force component difference with the non-grid side, thereby generating significant lift effects for the propeller of the ducted fan during level flight. Taking a ducted fan system as an example, a design method for embedding grids into the ducted wall is established. By using the sliding mesh technique to simulate propeller rotation, the effects of annular distribution angle, grid channel width, circumferential and flow direction grid quantity on its aerodynamic performance are evaluated. The results indicate that the ducted fan embedded in the grid can generate a lift about 22.16% of total thrust without significantly affecting thrust and power characteristics. The increase in circumferential distribution angle increases within a reasonable range and benefits the lift of the propeller. However, the larger the grid width, the more it affects the lip and tail of the duct. Ultimately, the overall effect actually deteriorates the performance. The number of circumferential grids has a relatively small impact. As the number of flow grids increases, the aerodynamic characteristics of the entire fusion configuration significantly improves, due to its favorable induction of airflow at the lip and tail of the duct, as well as blocking the dissipation of blade-tip vortices. Full article
(This article belongs to the Special Issue Multidisciplinary Collaborative Design of Aircraft)
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