Search Results (10,689)

This paper presents a computational study of wave–bathymetry and wave–structure interaction problems using advanced numerical techniques based on high-fidelity, two-phase Navier–Stokes (TpNS) flow and reduced-order, fully nonlinear potential flow models. For high-fidelity simulations, the TpNS equations are discretized using the finite-element method, with free-surface evolution captured through a hybrid level-set (LS) and volume-of-fluid (VOF) formulation. A monolithic, phase-conservative LS equation is introduced to mitigate mass loss and interface smearing, combined with a semi-implicit projection scheme. Hydrodynamic forces are resolved using a high-order, phase-resolving cut finite-element method (CutFEM), which enables the representation of complex solid geometries within a fixed background mesh. An equivalent polynomial of Heaviside and Dirac distributions ensures accurate evaluation of surface and volume integrals. Hence, no explicit generation of cut cell meshes, adaptive quadrature, or local refinement is required. For reduced-order modeling, a fast regularized boundary integral method (RBIM) is employed to solve the fully nonlinear potential flow. Singular and near-singular integrals are treated using a subtract-and-addition technique based on auxiliary functions derived from Stokes’ theorem, allowing direct application of high-order quadrature without conventional boundary element discretization. An arbitrary Lagrangian–Eulerian (ALE) formulation is adopted to enforce free-surface boundary conditions while avoiding excessive mesh distortion. The proposed approaches are applied to investigate highly nonlinear wave transformation over complex bathymetry and wave-induced dynamics of floating structures, including eddy-making damping effects. Numerical results are validated against experimental measurements. These two modeling approaches represent complementary levels of physical fidelity and computational efficiency, and their systematic comparison clarifies the trade-offs between computational accuracy, efficiency, and cost for practical marine problems. Full article

Decision Transformers (DTs) reformulate reinforcement learning as a conditional sequence modeling problem and have demonstrated competitive performance in offline Reinforcement Learning (RL) scenarios. However, their behavior in card games, specifically partially observable imperfect-information, trick-taking games remains underexplored. In parallel, general-purpose card-game toolkits have shown the value of unified environments and standardized evaluation protocols for accelerating research in imperfect-information games. Motivated by the goal of creating a general card-game-playing framework, we present a unified RL pipeline for trick-taking card games using DTs. While classical learning methods have demonstrated strong performance in card games, transformer-based reinforcement learning remains comparatively underexplored in this domain. This paper studies the applicability of DTs to the core play-phase of trick-taking games and evaluates whether a single, reusable pipeline can be transferred across multiple games in this class with minimal game-specific engineering. We propose a unified framework integrating offline pretraining, online selective expert iteration, and inference-time legal-action filtering. Crucially, our proposed approach demonstrates two key advantages over standard implementations. First, the model successfully internalizes complex game rules (e.g., follow-suit constraints) implicitly from the empirical data distribution, completely eliminating the need for explicit action masking during training. Second, we introduce a selective expert iteration mechanism equipped with strict acceptance filtering, which effectively prevents distribution collapse and enables safe, monotonic offline-to-online policy refinement. Ultimately, we show that this single, reusable transformer-based pipeline achieves competitive performance across multiple trick-taking domains (Hearts, Whist, and Spades) with minimal game-specific engineering. Full article

Experiential learning through simulations offers a unique but often underutilized opportunity to bridge the gap between pedagogy and empirical research. This study addresses this gap by transforming the Pemberton’s Dilemma simulation from a classroom exercise into a quantitative, empirical research project to investigate the dynamics of trust, cooperation, and opportunistic behavior. To address questions related to such trust interactions, the simulation was modified to include variable payout stakes, restricted and permitted communication phases, and an additional surprise round to measure long-term trust reputation effects. From 2017 through 2025, data was gathered from a convenience sample of 611 students from a large public university in the Northwestern United States. Results indicate that non-trusting behavior has a significantly greater mirroring effect than trusting behavior and that higher financial stakes frequently prime groups toward opportunistic hedging. While opportunistic strategies yielded greater short-term gains, longitudinal analysis revealed a significant positive correlation between consistent trust and monetary outcomes. Furthermore, the surprise round data confirmed that prior trust violations severely diminished cooperation and earnings in the future unknown round. The study supports the benefits of integrating quantitative research into pedagogical experiential tools to advance scholarly understanding (in this case of trust dynamics and the vital role of transparent communication and sustainability-compatible strategies), enhance student learning, and to provide data-driven recommendations for organizations. Full article

The growing importance of integrating renewable energy sources (RESs) into mainline railway traction networks stems from the sector’s substantial electricity demand, which is traditionally met by carbon-intensive thermal generation. This paper addresses the potential of wind power to enhance energy efficiency and reduce emissions in rail transport. It details the development of digital models for simulating DC traction power systems (TPSs) coupled with RESs, specifically wind turbines. Given the complexity of TPSs, effective integration requires digital modeling that accounts for their unique properties. The proposed methodology, based on phase coordinate algorithms, offers a universal and comprehensive framework. It enables the identification of various operational modes (normal, emergency, and special) for diverse network components, including traction networks, transmission lines, and transformers. These models were used to simulate real-world train operations, generating data on electrical parameter dynamics and transformer thermal conditions. The results confirm that wind integration can improve energy efficiency, validating the methodology’s practical applicability for RES projects in DC traction networks, including advanced high-voltage systems. Full article

The study investigates the microstructure evolution in the stir zone produced by the friction stir processing (FSP) of a heat-treated microalloyed Al-Mn-Cu alloy in the area subjected to the highest temperature, strain, and strain rate. The samples were studied using electron microscopy and atom probe tomography (APT) to obtain structural and chemical information from the macro to the nano scale. FSP refines the dendritic Al-rich solid solution grains through dynamic recrystallisation in the range of a few micrometres. The primary intermetallic phases were dispersed to the particles in the 0.5–3 µm range and transformed mainly into a more stable τ₁-Al₂₉Mn₆Cu₄ phase. The fraction of dispersed particles after FSP increased due to the precipitation from the solid solution during cooling. The nanoscale quasicrystalline precipitates in the matrix, formed upon heat treatment, dissolved entirely during FSP, while the strong coarsening of the L1₂ precipitates occurred due to high temperatures in the stir zone. After FSP, the hardness of the stir zone was nearly identical for specimens in the as-cast and heat-treated conditions. Full article

This study quantitatively evaluates the effect of solid-phase pre-reduction of chromite concentrate on the energy efficiency and techno-economic performance of high-carbon ferrochrome (HC FeCr) smelting. Laboratory pre-reduction experiments were conducted at 1200–1400 °C using Shubarkol coal, metallurgical coke, and special coke as carbonaceous reducing agents. Structural and phase transformations were characterized by X-ray diffraction (XRD) and scanning electron microscopy with energy-dispersive spectroscopy (SEM-EDS). At 1200 °C, the degree of metallization remained low (<5%), whereas at 1400 °C it increased to 41.3% under laboratory conditions and up to 65% in pilot-scale tests due to the decomposition of the spinel matrix and the formation of metallic and carbide phases. The application of pre-reduced feedstock in a submerged arc furnace reduced specific electricity consumption by up to 33.5% compared with conventional smelting and increased chromium recovery to 89.71%. Industrial-scale extrapolation indicates the potential to decrease power consumption to approximately 3190 kWh/t of alloy. Techno-economic analysis demonstrates that the use of pre-reduced feedstock reduces the production cost by approximately 10–23%, depending on the type of carbonaceous reducing agent (Shubarkol coal, metallurgical coke, or special coke). Special coke provided the highest energy efficiency, whereas Shubarkol coal ensured the greatest direct economic benefit. The integrated microstructural, energetic, and economic assessment confirms the industrial applicability of the proposed pre-reduction approach. Full article

Isosymmetric phase transitions driven by subtle hydrogen-bond rearrangements remain challenging for periodic density functional theory (DFT), particularly when energy differences between polymorphs are small. Resorcinol represents an interesting case in which the α and β polymorphs crystallize in the same space group and differ primarily in hydroxyl orientation and hydrogen-bond topology. In this work, the α–β phase transition was systematically investigated using periodic DFT calculations under ambient and elevated pressure. A broad set of exchange–correlation functionals combined with different dispersion corrections was benchmarked against experimental structural and energetic data. Dispersion-corrected methods were essential for reproducing lattice parameters and the pressure-induced inversion of stability. PBESOL with Tkatchenko–Scheffler dispersion provided the most consistent agreement with the experiment and was therefore used for phonon and ab initio molecular dynamics simulations. Phonon-derived thermodynamic analysis revealed a delicate enthalpy–entropy balance governing the transition, strongly affected by pressure. Dynamical simulations confirmed the instability of the α phase under compression, demonstrating the cooperative nature of this hydrogen-bond-driven isosymmetric transformation. Full article

Microcline is an important rock-forming mineral in the Earth’s crust, and characterizing its structural behavior under compression is essential for understanding the high-pressure response of feldspar minerals under geological conditions. In this study, the crystal structural evolution of microcline up to 12 GPa was investigated using first-principles calculations based on density functional theory. The results reveal an isosymmetric phase transition at approximately 6–7 GPa, accompanied by a ~7% volume collapse. Across this transition, the b-axis and unit-cell angles (α, β, γ) change abruptly, and the aluminum coordination transforms from fourfold to a distorted fivefold geometry intermediate between a trigonal bipyramid and a square pyramid. Analysis of bond lengths and angles indicates that compression in the low-pressure phase is primarily driven by shear deformation of tetrahedral Ring 1. Near the transition pressure, however, marked shear deformations of Ring 2 and Ring 3 induce a strong contraction of the b-axis and abrupt changes in the unit-cell angles. Comparison with the compression behavior of low albite reveals both similarities and distinct structural responses, highlighting the role of framework topology and extra-framework cations in controlling pressure-induced structural evolution in feldspar minerals. These results provide new insights into the high-pressure behavior of microcline and contribute to a better understanding of the structural stability of feldspar minerals in the Earth’s interior. Full article

This paper considers a principle for constructing transverse differential protection of two parallel 6–35 kV power transmission lines on the supply side, previously proposed by the authors and protected by a patent. Its implementation makes it possible to identify the damaged line without using current and voltage transformers, by employing signals from reed switches installed near the corresponding phases of the lines. The principle is based on monitoring the difference in magnetic field inductions produced by the currents in these phases and determining the damaged line according to the sequence of reed switch actuations. Based on experimental studies of the temporal characteristics of reed switches and on simulation of magnetic fields around the line phases, methodologies for selecting protection operating parameters and for evaluating its sensitivity, taking into account the influence of errors and currents in the phases of both lines, have been developed; the field of application of the protection, the cascade zone, and the locations for installing the reed switches have been determined. It is shown that the calculated cascade zone of the proposed protection can be up to 20% shorter than that of both the traditional protection and a similar reed-switch-based protection. At the same time, in comparison with the latter, implementation of the considered principle requires three times fewer reed switches. The elimination of current and voltage transformers, as shown by the calculations, creates prerequisites for reducing the resource intensity of the protection. Full article

This work investigates the effect of high-energy mechanical milling on the activation and phase transformation of synthetic pseudoboehmite powders. The approach aims to provide a clean, solvent-free route with potential industrial relevance for alumina production. Mechanical processing proved effective in inducing the transition from pseudoboehmite to χ-Al₂O₃ solely through milling. The process yielded nanometric particles with low levels of contamination. The subsequent conversion to α-Al₂O₃ was achieved through controlled heat treatments, while phase evolution was monitored by differential scanning calorimetry (DSC). A reduction of approximately 110 °C in the α-Al₂O₃ formation temperature was observed after 30 h of milling. This shift was accompanied by a marked decrease in the activation energy, from 526 kJ·mol⁻¹ for the raw powder to 347 kJ·mol⁻¹ for the milled sample. These results demonstrate the strong mechanochemical activation of pseudoboehmite, highlighting mechanical milling as an effective and scalable route for energy-efficient processing of alumina phases. Full article

Objective: The objective is to investigate and optimize the β-cyclodextrin inclusion process for volatile oils in Ligusticum Chuanxiong–Vinegar cyperus rotundus based on Quality by Design (QbD) principles. Methods: First, ligustilide and α-cyperone were selected as inclusion process indicator components using high-performance liquid chromatography–tandem mass spectrometry (HPLC-MS). Single-factor experiments were conducted to preselect the inclusion speed based on ligustilide and α-cyperone content as evaluation criteria. Subsequently, using the inclusion rates of ligustilide and α-cyperone as evaluation criteria, a factorial design was employed to investigate the inclusion temperature, inclusion time, and the volume ratio of β-cyclodextrin solution to essential oil, thereby optimizing the inclusion process parameters. Finally, the inclusion process parameters were validated, and the inclusion rates were determined. The obtained inclusion complexes were characterized by microscopic analysis, Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction analysis (XRD), and differential scanning calorimetry (DSC). Furthermore, phase dissolution studies and molecular docking were employed for confirmation. Results: The optimal process parameters were determined as follows: encapsulation speed of 300 rpm, β-cyclodextrin solution excess of 6, encapsulation time of 2.5~3 h, and encapsulation temperature of 30~35 °C. The encapsulation rates for ligustilide and α-cyperone in the resulting inclusion complex were 63.15~64.74% and 71.33~76.89%, respectively. Structural characterization confirmed the formation of the inclusion complex. Conclusions: This inclusion process is reliable and provides a reference for preparing β-cyclodextrin inclusion complexes of volatile oils in formulations containing the Chuanxiong–Vinegar cyperus rotundus drug pair. Full article

The endothelial protein C receptor (EPCR) is an important component of the protein C (PC) system, recognised for its diverse roles in blood coagulation, inflammation, and stem cell regulation. Wound healing is a complex physiological process that can be divided into four distinct but overlapping phases: haemostasis, inflammation, proliferation and remodelling. Recently, EPCR has emerged as a key regulator in wound repair and regeneration. During haemostasis, EPCR enhances the conversion of PC to its activated form (APC) to optimise local and systemic anticoagulation. In the inflammatory phase, EPCR modulates immune cell activity, inhibits inflammatory factors, and maintains tissue barrier integrity. As the process transitions to the proliferative phase, EPCR promotes endothelial and epithelial cell proliferation, migration, neovascularisation and re-epithelization, and mediates the expression of matrix metalloproteinases to facilitate tissue reconstruction. Finally, during the remodelling phase, EPCR exerts a potential antifibrotic effect by regulating fibroblast activation and collagen deposition via the Transforming growth factor (TGF)-β1/Smad3 pathway, ensuring functional repair. While therapeutic potential has been shown in animal models, translating EPCR-mediated therapies to clinical application faces many challenges, including wound heterogeneity, dosage control, targeted delivery, and potential bleeding risks. Studies have shown that local drug delivery strategies, non-anticoagulant APC variants, and individualised treatment based on EPCR expression will be the key directions for future development. Additionally, EPCR may serve as a potential biomarker for assessing wound severity and guiding personalised interventions. Full article

The relaxation calorimeter option in the commercial Physical Property Measurement System (PPMS) has become widely used. Since its introduction, the capabilities of this technique for specific heat measurements have been critically discussed, particularly to avoid misinterpretation of data near phase transitions. Traditional methods rely on cooling curves after sample excitation, where sharp latent heat contributions during heating lead to clear deviations from the fitting model. However, subtle but extended enthalpy contributions (e.g., strain release) may mask these effects, allowing both heating and cooling curves to be well fitted using the standard PPMS protocol. In this work, we develop a procedure that assumes a constant extra power supplied due to subtle enthalpy contributions, enabling consistent interpretation of both heating and cooling curves. This procedure allows: (1) correction of specific heat measurements; and (2) quantification of the enthalpy involved in the transition. The procedure is applied to a magnetic-field-induced transformation in MnCo(Fe)Ge(Si) alloys. Two samples were studied: a single-phase austenite without any field-induced transition, used as a reference, and a mixed austenite-martensite sample, in which apparent deviations in the conductance of the wires evidence the presence of the anomaly. Full article

Steels remain among the most widely used structural and engineering materials in modern infrastructure, energy systems, and industrial facilities. Their long-term reliability depends critically on the early detection of corrosion damage and microstructural degradation. This review surveys recent advances in two complementary families of non-destructive evaluation (NDE) methods: magnetic techniques, including magnetic Barkhausen noise (MBN), magnetic flux leakage (MFL), eddy current testing (ECT), and magnetic hysteresis analysis; and electrochemical methods including electrochemical impedance spectroscopy (EIS), linear polarization resistance (LPR), scanning vibrating electrode technique (SVET), and electrochemical noise (EN). Recent progress in sensor miniaturization, signal processing algorithms, and multi-technique integration is reviewed. Particular attention is given to the sensitivity of these methods to microstructural changes reported in the literature, including carbide dissolution, phase transformations, temper embrittlement, and sensitization in stainless steels, as well as to the conditions under which such sensitivity has been demonstrated. The potential synergy between magnetic and electrochemical monitoring is discussed as a possible pathway toward more robust, condition-based maintenance frameworks. Challenges related to field deployment, environmental interference, calibration, and data interpretation are identified, and future directions—including machine learning-assisted analysis and multi-physics sensor arrays—are outlined. Full article

Neoadjuvant strategies in head and neck squamous cell carcinoma (HNSCC) are reshaping therapeutic paradigms by shifting emphasis from anatomical staging toward biology-driven response stratification. The transition from induction chemotherapy to immune checkpoint–based and combination regimens has transformed the perioperative setting into a translational platform that enables interrogation of tumor–immune interactions and clonal selection under therapeutic pressure prior to surgery. In this context, pathological response assessment has emerged as a robust surrogate endpoint, overcoming the limitations of radiologic evaluation, which often fails to capture immune-mediated pseudoprogression and spatially heterogeneous regression. Quantification of residual viable tumor (RVT) provides a reproducible metric of therapeutic efficacy, while characterization of immune-related regression beds, tertiary lymphoid structures, macrophage polarization states, and compartment-specific nodal responses offers mechanistic insight into tumor clearance and resistance evolution. Evidence from phase II trials, single-cell sequencing, spatial transcriptomics, and multiplex immune profiling supports the prognostic relevance of pathology-driven endpoints. Integration of digital pathology and artificial intelligence–assisted image analysis further enhances reproducibility and enables high-resolution mapping of residual disease and immune architecture. Within this modern oncologic framework, the neoadjuvant-treated specimen functions as a dynamic biomarker platform guiding response-adapted surgical strategies and biomarker-driven clinical trial design. This study was designed as a narrative review. A structured literature search was performed using PubMed and major oncology journals to identify relevant studies on pathology-driven response assessment in neoadjuvant-treated head and neck squamous cell carcinoma. The review focused on publications addressing histopathological response criteria, immune microenvironment remodeling, spatial profiling technologies, and computational pathology approaches. Full article