Colloquiam: Documents published in 2025

Crossflow Turbine Wakes and Simulation Speed-up Using Wake Initialisation

Scipedia content — Fri, 14 Nov 2025 10:44:24 +0100

On the Merits of a Lifting Line Model for Simulating Hydrofoil Hydrodynamics

Scipedia content — Fri, 14 Nov 2025 10:42:39 +0100

Actuator Line Simulations of a Field Scale Cross Flow Tidal Turbine

Scipedia content — Fri, 14 Nov 2025 10:40:59 +0100

Numerical modelling of cross-flow turbines: 2D blade-resolved against 2D actuator line method simulations

Scipedia content — Fri, 14 Nov 2025 10:39:41 +0100

Development and Validation of an Actuator Line Method for Floating Turbines

Scipedia content — Fri, 14 Nov 2025 10:38:17 +0100

Comparing actuator line and disc models for the hydrodynamic design of tidal stream turbine rotors

Scipedia content — Fri, 14 Nov 2025 10:36:51 +0100

Analysis of Wind Turbine Wake Meandering Using the Actuator Disc Model

Scipedia content — Fri, 14 Nov 2025 10:35:36 +0100

Predicting the Hydrodynamic Performance of Inland Waterway Ships in Extreme Shallow Waters Using State-of-the-Art CFD

Scipedia content — Fri, 14 Nov 2025 10:28:01 +0100

Computational Fluid Dynamics Analysis of Ship Entry to Locks

Scipedia content — Fri, 14 Nov 2025 10:26:48 +0100

Detailed Numerical Modelling of Inland Navigation's Impact on Sediment Suspension

Scipedia content — Fri, 14 Nov 2025 10:25:20 +0100

Numerical simulation of naval hydrodynamics by the LBM-IBM coupling

Scipedia content — Fri, 14 Nov 2025 10:24:07 +0100

Cavitation prediction in high performance sailing, one year later.

Scipedia content — Fri, 14 Nov 2025 10:20:00 +0100

Experimental Investigation of two Typical Hydrofoil Sections with Cavitation

Scipedia content — Fri, 14 Nov 2025 10:18:31 +0100

Computational Fluid Dynamics as a performance aid tool in rowing: utopia or reality

Scipedia content — Fri, 14 Nov 2025 10:17:07 +0100

Experimental investigation of IQFoil Lift and Drag in a towing tank

Scipedia content — Fri, 14 Nov 2025 10:15:54 +0100

High Efficiency Swimming using Hydrodynamic Eigenmode Decomposition

Scipedia content — Fri, 14 Nov 2025 10:14:30 +0100

NACRA17 real time dynamic simulation

Scipedia content — Fri, 14 Nov 2025 10:13:05 +0100

Experimental study of ventilation inception on Olympic serie Kitefoil shaft

Scipedia content — Fri, 14 Nov 2025 10:11:42 +0100

Geometric Awareness in High-Order Numerical Modelling of Hydrofoils

Scipedia content — Fri, 14 Nov 2025 10:10:16 +0100

Time-Dependent Forces on an Accelerating Flat Plate

Scipedia content — Fri, 14 Nov 2025 10:08:53 +0100

Comparative Study of Aerodynamic Load Modeling Techniques for Aeroelastic Analysis of Hard Wingsails

Scipedia content — Fri, 14 Nov 2025 10:07:38 +0100

Simultaneous Optimization of Hydrofoil Design and Control Strategies: Application to a Pumping Foiler

Scipedia content — Fri, 14 Nov 2025 10:06:09 +0100

Experimental and Numerical Study of an Oscillating Foil Near the Free Surface

Scipedia content — Fri, 14 Nov 2025 10:04:30 +0100

Coupling athlete force profiles to rowing oar and boat loads simulated using rowing ergometry

Scipedia content — Fri, 14 Nov 2025 10:03:08 +0100

Computational Simulation of a Moored Floating Aquaculture Cage

Scipedia content — Fri, 14 Nov 2025 09:56:33 +0100

Design of Movable Aquaculture Net Cage at Multi Sea Site Based on Joint Probability Distribution of Environmental Loads

Scipedia content — Fri, 14 Nov 2025 09:55:16 +0100

Hydrodynamic Analysis of the Fishery-Photovoltaic Complementary Structure in Marine Conditions

Scipedia content — Fri, 14 Nov 2025 09:53:50 +0100

Numerical study on wave field around an offshore pile-net enclosure structure

Scipedia content — Fri, 14 Nov 2025 09:52:26 +0100

Advancing Computational Frameworks for Dynamic Towing Stability: A Review and Perspective

Scipedia content — Thu, 13 Nov 2025 12:24:04 +0100

Study on the hydrodynamic performance of propellers in stratified environments with temperature and salinity gradients

Scipedia content — Thu, 13 Nov 2025 12:22:39 +0100

Evolution of wall pressure fluctuations in flow over the DARPA SUBOFF model

Scipedia content — Thu, 13 Nov 2025 12:21:15 +0100

Ship hydroelastic responses and slamming loads of an ultra-large containership in different conditions

Scipedia content — Thu, 13 Nov 2025 12:19:51 +0100

Hydroelastic response of tubular structures to water impact: Theory and Experiments

Scipedia content — Thu, 13 Nov 2025 12:18:32 +0100

Implementing VOF-PLIC Methods into REEF3D::CFD for Detailed Modelling of Breaking Waves

Scipedia content — Thu, 13 Nov 2025 12:17:07 +0100

A Quasi-Simultaneous FSI Method for Deformable Offshore Structures

Scipedia content — Thu, 13 Nov 2025 12:15:43 +0100

Numerical Wave Generation and Propagation with High Order Spectral Method in OpenFOAM

Scipedia content — Thu, 13 Nov 2025 11:41:53 +0100

Modeling the submarine landslides and tsunamis triggered by the Tagoro eruption

Scipedia content — Thu, 13 Nov 2025 11:40:23 +0100

Application and Validation of IHFOAM for Modelling Wave Interaction with Rubble-Mound Breakwaters: A Case Study from Bilbao Port (Spain) Supporting Predictive Maintenance Strategies

Scipedia content — Thu, 13 Nov 2025 11:38:59 +0100

FloatStepper: A robust rigid body-fluid coupling algorithm for OpenFOAM

Scipedia content — Thu, 13 Nov 2025 11:37:36 +0100

RANS-VOF simulations of breaking waves

Scipedia content — Thu, 13 Nov 2025 11:36:14 +0100

OpenFOAM-based hybrid CPU/GPU coupled solver on Navier-Stokes equations and shallow water equations

Scipedia content — Thu, 13 Nov 2025 11:35:01 +0100

Covering submarine pipelines: numerical analysis of the influence of subsea currents in falling granular material

Scipedia content — Thu, 13 Nov 2025 11:33:45 +0100

A 3D-CFD Analysis of Gas Direct Injection for a Dual-Fuel Medium Speed Marine Engine

Scipedia content — Thu, 13 Nov 2025 11:22:11 +0100

Reliability constraints in the topology generation of ship architecture

Scipedia content — Thu, 13 Nov 2025 11:20:44 +0100

Generative Ship Hull Form Optimisation with ShipHullGAN

Scipedia content — Thu, 13 Nov 2025 11:19:17 +0100

Elastic local buckling behaviour of ultra-long wind turbine blades with flexible core supports

Scipedia content — Thu, 13 Nov 2025 11:17:49 +0100

Integrated Design of Propeller and Multiple Energy Saving Devices with Consideration of Their Interaction

Scipedia content — Thu, 13 Nov 2025 11:16:29 +0100

The Influence of Seaway Parameters on the Generalizability of a Force-Correcting Machine Learning Method

Scipedia content — Thu, 13 Nov 2025 11:14:58 +0100

Improving Multi-fidelity Surrogate Modelling by Updating the Uncertainty Estimation

Scipedia content — Thu, 13 Nov 2025 11:13:32 +0100

Thermomechanical Loading Induced Buckling and Failure Analysis of Thermoplastic Composite Pipes

Scipedia content — Thu, 13 Nov 2025 11:12:04 +0100

Statoric Blades Effect on the Efficiency of a RANS-Optimized Rim-Driven Thruster

Scipedia content — Thu, 13 Nov 2025 11:10:49 +0100

Comparison of Polynomial Chaos Expansion and Polynomial Chaos Kriging for Uncertainty Quantification of NACA66(MOD) Hydrofoil

Scipedia content — Thu, 13 Nov 2025 11:09:14 +0100

Using CFD To Develop a Fully Electric Motor Driven Contra-Rotating Propulsion System for Marine Vessels

Scipedia content — Thu, 13 Nov 2025 11:07:44 +0100

Simulation-base Optimization of a Propeller for a Navy Ship

Scipedia content — Thu, 13 Nov 2025 11:06:19 +0100

A Comparative Investigation of a new Multi-fidelity Bayesian Optimization Framework for Surrogate-Based Design Optimization

Scipedia content — Thu, 13 Nov 2025 11:04:58 +0100

Preliminary Design Optimization for Internal Arrangement and Hull Geometry of a Bio-Inspired Autonomous Underwater Glider through Machine Learning

Scipedia content — Thu, 13 Nov 2025 11:03:32 +0100

Multi-Fidelity Hydro-Structural MDO for High-Speed Small Craft via Multi-Loop Digital Design

Scipedia content — Thu, 13 Nov 2025 11:02:02 +0100

Robust Parametric Models for Simulation- and Data-driven Design

Scipedia content — Thu, 13 Nov 2025 11:00:36 +0100

Where Are We and Where Are We Going? Analyzing Simulation-Driven Design Optimization Trends in Marine Engineering by Scoping Review

Scipedia content — Thu, 13 Nov 2025 10:59:12 +0100

Enhancing Ship Propeller Design via Physics-Informed Parametric Model Embedding

Scipedia content — Thu, 13 Nov 2025 10:57:47 +0100

Systems Elements Analysis: Integrating Model-Based Systems Engineering with Early-Stage Ship Design Tools

Scipedia content — Thu, 13 Nov 2025 10:56:22 +0100

Development and Mesh Guidelines of the Acoustics Overlapping Mesh Technique

Scipedia content — Thu, 13 Nov 2025 10:26:10 +0100

Underwater Radiated Noise prediction of a navy vessel using a hybrid method

Scipedia content — Thu, 13 Nov 2025 10:24:45 +0100

Hydroacoustic Pattern of Twin Propellers with Hull Interaction

Scipedia content — Thu, 13 Nov 2025 10:23:22 +0100

Study on Effects of Wake Distribution for Underwater Radiated Noise

Scipedia content — Thu, 13 Nov 2025 10:21:47 +0100

Numerical Modelling of Underwater Radiated Noise from a Rigid Foil

Scipedia content — Thu, 13 Nov 2025 10:20:18 +0100

Bow thruster unsteady effects reduction, a numerical study

Scipedia content — Thu, 13 Nov 2025 10:18:50 +0100

Predicting Underwater Radiated Noise with AI-Driven Virtual Sensor Technology

Scipedia content — Thu, 13 Nov 2025 10:14:29 +0100

Investigation of Turbulence Models and Blockage Effects on Numerical Hydro-Acoustics Studies

Scipedia content — Thu, 13 Nov 2025 10:13:08 +0100

High-fidelity simulations of sound propagation in the oceans

Scipedia content — Thu, 13 Nov 2025 10:11:42 +0100

Underwater Radiated Noise Comparison between Low and High Fidelity Methods

Scipedia content — Thu, 13 Nov 2025 10:10:15 +0100

Computational Modelling of Underwater Ocean Acoustic Propagation with Acoustic Perturbation Equations

Scipedia content — Thu, 13 Nov 2025 10:08:51 +0100

The Acoustic Signature of a Contra-Rotating Propeller in Wetted Conditions

Scipedia content — Thu, 13 Nov 2025 10:07:25 +0100

Efficient Propeller Noise Prediction Using the Stochastic Noise Generation and Radiation Model with U-RANS Simulations

Scipedia content — Thu, 13 Nov 2025 10:05:58 +0100

Innovación y Gobernanza para un Agroturismo Rural Sostenible: Claves para la Resiliencia Territorial

Claudia Patricia De Aguas Gonzáles — Tue, 11 Nov 2025 19:32:13 +0100

El presente estudio examina la importancia de la innovación y la gobernanza como ejes estratégicos para consolidar un agroturismo rural sostenible y aportar a la resiliencia territorial. El objetivo central consistió en determinar cómo estas dimensiones inciden en la diversificación económica, la competitividad local y la cohesión social. La investigación se sustentó en una revisión documental de artículos científicos publicados entre 2020 y 2024, lo que permitió integrar aportes recientes vinculados con la innovación tecnológica, la gobernanza inclusiva y la sostenibilidad en el marco del agroturismo. Los resultados ponen de manifiesto que la implementación de tecnologías, acompañada de modelos de gobernanza participativa, promueve la conformación de redes colaborativas transparentes, optimiza la gestión de los recursos y fortalece los procesos de decisión colectiva. De igual forma, se observa que la innovación aplicada al agroturismo favorece la diversificación productiva, además de resguardar el patrimonio cultural y ambiental de los territorios. No obstante, persisten retos asociados a la apropiación tecnológica por parte de las comunidades rurales y su traducción en prácticas efectivas de gobernanza. Estas limitaciones abren la posibilidad de nuevas investigaciones encaminadas a explorar los alcances y restricciones de la integración entre innovación, gobernanza y resiliencia territorial en contextos de agroturismo.

Tierra Viva: La Fuerza del Agro y el Encanto del Turismo en Sucre

MARIA JOSE LARA VILORIA — Tue, 11 Nov 2025 19:31:23 +0100

El presente artículo revisorio analiza la evolución y el potencial de la agroindustria y el agroturismo en el departamento de Sucre (Colombia), con especial atención en los municipios de Chalán, Colosó, Santiago de Tolú y Toluviejo. A partir de fuentes oficiales, informes institucionales y experiencias locales, se examina la articulación entre el sector agrícola, las prácticas turísticas rurales y las oportunidades de desarrollo sostenible. Se evidencian las sinergias entre tradición y modernidad, y se plantean estrategias para impulsar la identidad territorial, la economía circular y la gobernanza comunitaria.

Foundation-model governance pathways: from preference models to operative rules

Agustin V. Startari — Tue, 11 Nov 2025 13:59:43 +0100

Current research on foundation model alignment concentrates on preference optimization and reward model design, yet it does not explain how these mechanisms become enforceable linguistic structures in model outputs. This paper introduces a formal bridge between training choices and governance-level effects by defining the operative rule as a compiled constraint that determines which clause types a model may produce. The framework maps policy inputs such as statutes, institutional directives, and redline restrictions into a preference graph over clause types, then compiles those directives into executable constraints that control decoding. It proposes measurable clause-level metrics including coverage, leakage, authority-bearing density, and constraint satisfaction, together with an auditable chain of custody that links governance inputs to observable textual outcomes. Cross-domain simulations in healthcare, securities disclosure, and administrative reporting demonstrate how governance parameters can be enforced without access to proprietary weights. The result is a verifiable clause calculus that operationalizes accountability and replaces abstract alignment narratives with testable governance artifacts connecting preference models to the operative law embedded in generated text.

DOI

Primary archive: https://doi.org/10.5281/zenodo.17533075
Secondary archive: https://doi.org/10.6084/m9.figshare.30589940
SSRN: Pending assignment (ETA: Q4 2025)

Anti-Erosion Behavior and Mechanism of Novel Graphene-Modified WC Coatings under High-Velocity Solid-Liquid Impingement

Jiangshuai Wang — Sun, 09 Nov 2025 08:49:33 +0100

''':This study investigates the anti-erosion mechanisms of a novel graphene-modified tungsten carbide coating under high-speed solid-liquid two-phase flow conditions. A liquid-solid two-phase flow erosion simulation device was employed, and fluid dynamics simulations were conducted using FLUENT software to determine the maximum experimental flow velocity. The influence of flow velocity, sand particle diameter, sand concentration, and fluid temperature on the erosion rate of the coating was systematically analyzed using the control variable method. Experimental results reveal that the erosion rate follows a power-law exponential relationship with flow velocity. When the sand particle diameter is below 0.5 mm, the erosion rate remains relatively stable; however, when the diameter exceeds 0.5 mm, the erosion rate increases significantly with particle size. Furthermore, the erosion rate exhibits a slight increase with higher sand concentrations, while a notable rise in fluid temperature leads to a substantial increase in the erosion rate, with the difference in erosion rates between the 150°C and 200°C coatings becoming more pronounced at elevated temperatures. Scanning electron microscopy (SEM) and numerical simulations were utilized to further elucidate the anti-erosion mechanisms of the coating. The incorporation of tungsten carbide significantly enhances the coating's hardness, while the addition of graphene results in a denser microstructure, effectively reducing porosity and improving the coating's resistance to impact and erosion. The findings demonstrate that the novel graphene-modified tungsten carbide coating exhibits superior erosion resistance, making it highly suitable for enhancing the durability and performance of rigid PDC drill bits in complex downhole environments.

Function-calling Schemas as De Facto Governance: Measuring Agency Reallocation through a Compiled Rule

Agustin V. Startari — Wed, 05 Nov 2025 14:31:23 +0100

Function-calling schemas, presented in practitioner guides as mechanisms for structured output, operate as de facto governance instruments within model–tool ecosystems. While most documentation focuses on syntactic validity and schema adherence, little attention has been paid to how parameter defaults, validators, and enforced signatures redistribute agency among the operator, the model, and the external tool. This paper introduces the Agency Reallocation Index (ARI), a quantitative measure that captures this redistribution through entropy reduction and Shapley attribution across three control dimensions: operator, model, and tool. Treating the schema as a regla compilada (a compiled rule that pre-structures permissible actions), the study demonstrates how defaults and validation layers govern results as effectively as explicit human instruction. A factorial experiment over controlled tool-calling tasks isolates the effects of validator strictness, default intensity, and signature breadth on agency allocation. The findings show that higher validator rigidity or hard defaults consistently increase tool agency while compressing model autonomy, exposing a governance gradient encoded in interface design. The paper concludes that schema architecture not only constrains model behavior but also formalize a programmable distribution of authority that should be audited alongside conventional metrics of accuracy and reliability.

DOI

Primary archive: https://doi.org/10.5281/zenodo.17533080
Secondary archive: https://doi.org/10.6084/m9.figshare.30541049
SSRN: Pending assignment (ETA: Q4 2025)

The Effect of Salvia miltiorrhiza on the Memory of Dugesia dorotocephala

Vicky Lin — Fri, 31 Oct 2025 19:36:33 +0100

In this experiment, the ability of sage, Salvia miltiorrhiza on memory retention and the organism population was assessed. Sage shows effects by aromatherapy, with active chemical properties to improve cognitive and neurological performance. This experiment used planarians as a neurological template to show the effects of the properties of sage. The planarians were separated into groups A, B, C, D, and E, each with ten individuals. Group A was the control, B was 0.001g/mL, C was 0.002g/mL, D was 0.003g/mL, and E was 0.004g/mL. It was predicted that the higher the concentration, the better the memory retention performance. This experiment compared the after-treatment results of the memory retention examination and to the before-treatment values through Excel, ANOVA with Tukey HSD, and t-tests. Results from trial 1 demonstrated that the sage solution improved the planarians' ability to retain information. Groups B and C performed better when compared to control group A and pre-treatment values. In trial 2, almost all the experimental groups outperformed the control group equally. After trial 3, group E showed the most significant results after treatment. In conclusion, sage was able to improve the memory retention of the planarians. Group A has the least change in memory retention; groups C and D showed effect after two days from treatment; groups B and E showed the most immediate effect. However, future research should be conducted to address more specific patterns between sage solution concentrations and memory retention of the planarians.

Successive approximation method for solving (1+1)-dimensional dispersive long wave equations

bewar ali — Wed, 29 Oct 2025 21:07:34 +0100

In this paper, we study the (1+1)-dimensional dispersive long wave equations which describe the evolution of horizontal velocity component u(

On Observer-Based Control of One-Sided Lipschitz ω-Tempered Fractional-Order Systems under Input Saturation

Jesús Sánchez Pinedo — Wed, 29 Oct 2025 10:32:33 +0100

This paper addresses the critical challenge of observer-based control for one-sided Lipschitz (OSL) nonlinear systems governed by tempered fractional-order dynamics under input saturation constraints. We introduce a novel stability framework combining ω-tempered Caputo derivatives with Mittag-Leffler stability theory, enabling significantly faster exponential error decay compared to classical fractional operators. The proposed methodology features three key innovations: (1) a tempered Mittag-Leffler stability theorem incorporating sector-bounded saturation nonlinearities, (2) linear matrix inequality (LMI) conditions accommodating arbitrary OSL constants (ρ∈ R), and (3) a Cone Complementary Linearization (CCL) algorithm resolving gain synthesis challenges in tempered fractional systems. Numerical validation demonstrates 62% faster convergence than classical fractional approaches while maintaining saturation constraints. The CCL algorithm provides guaranteed convergence with computational efficiency, overcoming initialization sensitivity through regularization techniques.OPEN ACCESS Received: 05/06/2025 Accepted: 15/08/2025 Published: 27/10/2025

Numerical Simulation, Physical Modeling and Plant Trial on the Slag Entrapment Behavior in a Four-Strand Tundish

Jesús Sánchez Pinedo — Wed, 29 Oct 2025 10:31:24 +0100

The continuous casting process yields more than 96% crude steel worldwide. Numerical simulation and physical modeling were employed to investigate the slag entrainment behavior during the final casting stage in a four-strand continuous casting tundish. It is demonstrated that the numerical and physical modelling results agree well. Vortex formation in the final casting stage can be divided into four distinct stages: surface rotation, vortex generation, vortex development, and vortex penetration, with significant variations in critical slag entrainment depths observed among different outlets. Increasing casting speed increases slag entrainment risks, while employing vortex inhibitors could reduce the critical slag entrainment height by up to 29%. Through optimized casting termination procedures in a plant trial, the tundish residual depth decreased from 400 to 200 mm; The tail-end billet cleanliness significantly improved to reach a normal billet quality level in the end billet range of 2–3 m. This study provides theoretical and technical support for reducing slag entrainment defects and improving steel cleanliness in continuous casting.OPEN ACCESS Received: 15/05/2025 Accepted: 10/07/2025 Published: 27/10/2025

A Comparative Analysis of the Boundary Condition Schemes for an Immersed Cylinder in a Water Stream with the Lattice Boltzmann Method

Jesús Sánchez Pinedo — Wed, 29 Oct 2025 10:29:34 +0100

In this paper, we investigate the performance of different boundary condition (BC) schemes for curved walls within the framework of the Lattice Boltzmann Method (LBM). A canonical benchmark problem—the flow past a circular cylinder in a channel—is considered, with Reynolds numbers ranging from 50 to 300. While prior studies have examined similar configurations, this work provides a novel comparative analysis under realistic conditions—using dimensional LBM simulations with actual fluid properties and consumer-grade hardware, rather than idealized lattice units. Additionally, we introduce an in-house GPU-accelerated solver, enabling efficient high-fidelity simulations without reliance on specialized computational resources. Four wall boundary conditions—the standard bounce-back scheme, the non-equilibrium extrapolation scheme, the fictitious equilibrium scheme and a one-point scheme—are implemented and analyzed through their influence on the time-averaged drag coefficient of the cylinder. The results are compared against both experimental and Navier-Stokes-based numerical data to assess accuracy. Additionally, the study evaluates the relative impact of outlet BC selection on simulation fidelity. The findings show that all tested solid wall boundary schemes can produce reasonable predictions under suitable conditions. Furthermore, based on our results, the accuracy of LBM simulations is notably more sensitive to the choice of the outlet boundary condition when compared to the choice of the ones used at the immersed body.OPEN ACCESS Received: 08/05/2025 Accepted: 24/06/2025 Published: 27/10/2025

Effects of Fetal Development on Umbilical Artery Hemodynamics: A Computational Fluid Dynamics Study with Doppler Ultrasound

Jesús Sánchez Pinedo — Wed, 29 Oct 2025 10:28:24 +0100

The umbilical artery (UA) plays a vital role in the exchange of substances between the mother and fetus through fetal circulation. In silico computational fluid dynamics (CFD) has emerged as an effective tool for simulating and analyzing UA blood flow, especially when combined with clinical Doppler ultrasound data. However, most existing studies have applied CFD to investigate UA hemodynamics only at isolated stages of gestation. In reality, UA hemodynamics undergoes continuous changes throughout fetal morphogenesis and physiological development during the entire gestational period. To address this gap, the present study employs CFD to investigate the evolution of UA hemodynamics across eight consecutive gestational age groups: 19, 23, 25, 27, 30, 33, 36, and 39 weeks. The simulations are based on Doppler ultrasound data acquired from clinical examinations of fetuses. The results demonstrate that UA blood flow velocity, secondary helical flow intensity, pressure drop, and wall shear stress generally increase with advancing gestational age. Furthermore, statistical analysis of clinical data across different gestational weeks reveals that the ratio of the Dean number to the Reynolds number (i.e., square root of the dimensionless curvature) remains basically stable during fetal development, with a value of 0.57 ± 0.06. This finding offers new insight into the scaling behavior of UA flow dynamics and may serve as a useful reference for clinical assessments. Overall, this CFD-based investigation provides a comprehensive characterization of UA hemodynamic development and may assist clinicians in gaining a deeper understanding of fetal circulatory adaptation throughout gestation.

Dynamic and Control in a Three-Variable Chemical Reaction Model

Jesús Sánchez Pinedo — Wed, 29 Oct 2025 10:27:33 +0100

Chaotic behavior in nonlinear chemical systems presents significant challenges for stability and control, particularly in practical applications. This study investigates the suppression of chaos in a three-variable reaction system through an optimal linear feedback strategy, formulated via the solution of an algebraic Riccati equation. The proposed control approach effectively eliminates chaotic oscillations, guiding the system to equilibrium even under parameter uncertainties of up to 20%. Numerical simulations confirm that the control action maintains high robustness, ensuring convergence with minimal effort. The stabilization time for x

Optimum Analysis and Parameter Inference of a New Improved Adaptive Progressive Unit-Weibull Model Censoring with Two Physical Applications

Jesús Sánchez Pinedo — Wed, 29 Oct 2025 10:26:18 +0100

Recently, a new bounded version of the Weibull lifetime has been introduced, retaining the flexibility of the standard Weibull model while restricting it to the unit interval, making it particularly useful for betalike modeling in various fields. This paper investigates the improved adaptive Type-II progressively censored plan by applying it to the bounded unit Weibull distribution. From a frequentist perspective, both maximum likelihood and maximum product of spacings methods are used, along with appropriate approximate confidence intervals. Bayesian point estimates, along with Bayesian credible intervals, are obtained using classical procedures that involve Markov-Chain Monte Carlo sampling, with two separate posterior distributions based on the squared error loss. The proposed estimation frameworks encompass both distribution parameters and key reliability metrics, notably the reliability and failure rate functions. Extensive simulations are conducted to evaluate the accuracy and efficiency of the estimators under various censoring levels, sample sizes, and thresholds. To determine the optimal removal strategy under both frequentist estimation paradigms, several metrics are proposed. Additionally, the model is applied to two real-world datasets from engineering reliability; one contains core samples from petroleum reservoirs collected across four cross-sections, and the other pertains to the tensile strength of polyester fibers, illustrating its practical utility and flexibility in modeling. The novelty of this study lies in integrating the bounded support of the unit-Weibull model with an improved adaptive censoring scheme, providing enhanced robustness and adaptability in reliability analysis across different fields.OPEN ACCESS Received: 21/06/2025 Accepted: 19/08/2025 Published: 27/10/2025

Approximate Calculation of the Generalized Erdélyi-Kober Operator Using a Cubic Spline

Jesús Sánchez Pinedo — Wed, 29 Oct 2025 10:24:24 +0100

This article investigates the problem of approximating the generalized Erdélyi-Kober fractional operator (often referred to as the Lowndes operator) using cubic splines. A method based on cubic spline interpolation is proposed for approximating the operator on a non-uniform grid. The convergence rate of the proposed method is proven, and its stability is analyzed. Error bounds are established for functions in the class C4[0; b], providing a mathematical justification for the accuracy of the approximation. The efficiency of the method is validated through practical examples using test functions such as f (x)= x4.7and f (x)= cos x, with results presented in graphical and numerical forms. This approach ensures high accuracy and flexibility in computing fractional integrals, which is of significant importance for solving fractional models used in physics, engineering, and other sciences. The article also provides an overview of the role of the generalized Erdélyi-Kober operator in modern fractional calculus and its applications.OPEN ACCESS Received: 06/06/2025 Accepted: 08/09/2025 Published: 27/10/2025

Fundamental Mechanics and Precision Control of Optical Axis Stability and Parallelism in Multi-Sensor Electro-Optical Pods

Jesús Sánchez Pinedo — Wed, 29 Oct 2025 10:23:45 +0100

Modern electro-optical pods incorporatemulti-spectral sensors for reconnaissance,

target acquisition, and laser designation, where sub-milliradian

optical axis stability and inter-sensor parallelism are critical for mission

success. This paper establishes a unified theoretical framework combining

rigid-body kinematics and deformable body mechanics to develop a

physics-based stability metric through screw theory formulation, expressing

the optical axis dynamics as ˙O = [ω]×O+v, with thermo-mechanical

constraints [ω]×O < ω, v < v for engineering implementation. A

novel computational geometry method evaluates multi-sensor alignment

errors by solving Ei = si − (si · ˆO)

ˆO

+ JTT + Jgg, where JT and Jg

represent thermal and gravitational Jacobians. The rigid-flexible coupling

model with multi-point constraints (MPC) reveals thermal dominance

(0.49 mrad IR sensor pitch displacement at 60◦C, 272× gravitational

effect), material sensitivity (CTE mismatch contributing 68% of TV sensor’s

azimuthal error), and cross-axis coupling (19% LD error amplification

under thermal gradients). However, due to the limitations of current

experimental conditions, the experimental validation ismainly carried out

in controlled environments. The current experimental validation shows

<5% deviation between predicted andmeasured parallelismerrors across

−20◦C to 60◦C. In the future, we will supplement the evaluation of the

robustness of the control method through existing simulation verifications

(such as adding vibration and temperature disturbance models) in the

“experimental discussion” or “prospect” section, and clarify the research

plan for actual environment testing. The framework provides design

guidelines for optimal sensor placement minimizing JT

F, temperaturedependent

calibration protocols, and 0.1 mrad allocable margin for manufacturing

tolerances. This methodology advances electro-optical system

engineering fromempirical tuning tomodel-driven optimization, demonstrating

0.12 mrad (3σ) stability in field tests under ISO 9022 environmental

stress profiles, with key innovations including the first integration

of Lie algebra kinematics with FEM-based deformation analysis for

optical systems and physics-informed error budgeting separating thermal,

mechanical, and alignment components.

On Nonlinear Monge-Ampère Equations and Their Symmetry Classifications

Jesús Sánchez Pinedo — Wed, 29 Oct 2025 10:20:24 +0100

The Monge-Ampère equation (MAE) plays a pivotal role across a broad spectrum of theoretical and applied sciences, with its solutions being essential for advancing various fields. This study explores all forms of the fully nonlinear MAE using Lie group transformations to reduce the equation into solvable forms. Analytical solutions are derived using ansatzbased methods, yielding novel and generalized results that enhance the existing body of knowledge. In particular, solutions for cases with diverse source functions and boundary conditions are obtained, addressing gaps in the literature. Stability of the solutions is studied through both analytical and numerical approaches. Comparisons with existing solutions demonstrate the efficiency and generality of the proposed methods. The results presented in this work are poised to impact numerous applications, providing a robust framework for further research on MAEs.OPEN ACCESS Received: 24/05/2025 Accepted: 07/08/2025 Published: 27/10/2025

RCS Simulation of Double S-Shaped Inlet with Radar Absorbing Materials Shedding Using Iterative Physical Optics with Impedance Boundary Condition

Jesús Sánchez Pinedo — Wed, 29 Oct 2025 10:18:54 +0100

The inlet of an aircraft engine is a primary contributor to the aircraft’s forward electromagnetic scattering. S-shaped inlet and radar absorbing materials (RAM) coatings have been widely adopted as effective measures to reduce forward radar cross section (RCS). To investigate the influence of RAM shedding on the RCS reduction efficiency, the electromagnetic scattering characteristics of the inlet under five different shedding probabilities were calculated using the iterative physical optics (IPO) combined with impedance boundary condition (IBC). Numerical simulation results demonstrate that the forward RCS of the S-shaped inlets increases monotonically with shedding probability. In the yaw plane, intact non-magnetic RAM exhibits better RCS reduction efficiency (RRE) than that in the pitch plane across all scenarios. Specifically, at a shedding probability of 0.7, the remaining non-magnetic RAM maintains an RRE exceeding 40% in the pitch plane. Collectively, these results suggest that recoating the nonmagnetic RAM is recommended when the shedding probability exceeds 0.7 in either detection plane to sustain critical stealth performance.OPEN ACCESS Received: 20/05/2025 Accepted: 13/08/2025 Published: 27/10/2025

Deep Learning Approaches for Hydrological Forecasting: A Systematic Review

Jesús Sánchez Pinedo — Wed, 29 Oct 2025 10:14:09 +0100

Machine learning (ML) techniques, especially Deep Learning (DL) techniques, have been applied for flood risk analysis and prediction on spatial historical data to minimize the risk of the loss of lives and properties associated with floods. In recent years, various studies have established DL as an effective approach for building potential flood prediction models. However, a thorough, systematic integration of recent advancements in DL for hydrological forecasting, their reported performance, and challenges is essential for guiding future work effectively. This paper presents a systematic survey of various DL models applied to flood prediction. This systematic review integrates studies published between 2018 and 2025 that used DL models in hydrological forecasting, such as flood prediction, streamflow forecasting, and runoff modeling. A systematic search of major electronic databases was performed using pre-defined inclusion and exclusion criteria. The overall search provided 647 records, which were narrowed down to a final collection of 45 studies after screening and full-text examination based on factors like study design, hydrological forecasting relevance, and application of DL. The review quantitatively summarizes the reported performances of various DL models, including RNN variants (LSTM, GRU), CNN, GAN, and hybrid architectures, across different hydrological forecasting tasks and datasets. Findings indicate that DL models consistently achieve high performance metrics such as NSE of (0.99), RMSE of (24.61) and MAPE of (1.73) for certain applications. Despite these advancements, significant research gaps remain, particularly concerning the scarcity of high-quality, publicly available datasets with detailed spatial information, the need for more robust real-time prediction systems with minimized false alarms, and the development of more generalized models applicable across diverse geographical regions. this review highlights the significant potential of DL in hydrological prediction as well as clearly stating the fundamental challenges that need to be overcome in order to achieve more robust and generalizable flood prediction systems.OPEN ACCESS Received: 25/04/2025 Accepted: 22/07/2025 Published: 27/10/2025

Inference of the Exponentiated Rayleigh Distribution on Step-Stress Accelerated Life Testing under Type-I Hybrid Censored Data with Physical Application

Jesús Sánchez Pinedo — Wed, 29 Oct 2025 10:12:34 +0100

This paper aims to estimate the unknown parameters for the exponentiated Rayleigh distribution using Type-I hybrid censored data under a step-stress model. The maximum likelihood and Bayes methods estimate the parameters and acceleration factor. The parameters’ approximate confidence intervals are created. The Bayes estimates of the parameters for the squared error and linear exponential loss functions are computed using the Markov Chain Monte Carlo (MCMC) method. Finally, we perform a simulation study to evaluate the effectiveness of the proposed estimators. We provide a real-life data example (Strength data measurement in GPA, for single and impregnated carbon fibers) to explain the obtained results.OPEN ACCESS Received: 15/04/2025 Accepted: 21/08/2025 Published: 27/10/2025

Effects of the Trapezoidal Embedded Loading Berm on the Stability of Soft-Soil Foundation Embankment

Jesús Sánchez Pinedo — Wed, 29 Oct 2025 10:11:34 +0100

The traditional loading berm is effective in reinforcing soft-soil foundation embankments, however, it is found that its large footprint limits its application in some narrow construction sites in recent years. Therefore, to address this limitation, the trapezoidal embedded loading berm (TELB) has been introduced, and its feasibility was examined in this paper. Firstly, an analytical model was developed to investigate the mechanical behavior of the TELB. Then, a numerical approach was employed to assess the TELB’s efficacy in enhancing the stability of soft-soil foundation embankments. The study elucidates the impact of various TELB parameters— such as slope angle, lower edge width, height, density, internal friction angle, and cohesion—on the embankment stability coefficient. Finally, an orthogonal test was conducted to evaluate the sensitivity of each parameter concerning embankment stability. The results demonstrate that the TELB substantially improves the stability of soft-soil foundation embankments, with stability coefficients increasing as the geometric and physicalmechanical parameters of the loading berm are enhanced. Among the parameters, height and density exert a more pronounced effect on the stability coefficient compared to cohesion and internal friction angle. This research provides valuable insights for the design and construction of TELBs and contributes to mitigating the environmental impact of road construction in soft soil regions.OPEN ACCESS Received: 23/03/2025 Accepted: 10/06/2025 Published: 27/10/2025

Optimizing peridynamic microparameters for accurate representation of elasticity, plasticity, and shear localization in geomaterials

Scipedia content — Wed, 29 Oct 2025 09:59:35 +0100

Geomaterials exhibit complex failure mechanisms characterized by strain localization and discontinuities (such as micro-crack formation and propagation), posing substantial challenges in their numerical modelling using the continuum-based methods. These limitations are typically addressed through algorithmic interventions or by using a non-local formulation. Peridynamic is one such method that inherently overcomes these limitations by replacing the partial differentials with non-local integral equations, enabling material points to interact with neighbouring points within a defined horizon. Similar to other numerical approaches, the application of peridynamic in geomechanics necessitates precise calibration of elastic parameters, as they play a crucial role in governing the plastic behavior of geomaterials. In this context, the present investigation studied the optimization of non-ordinary state-based peridynamic formulations using a geomaterial test specimen with a 1:2 aspect ratio under compression to evaluate the influence of critical numerical parameters, namely horizon size and material points discretization, on the accuracy of predicted elastic modulus. The results highlighted the necessity of selecting optimal combinations of mesh density and horizon size to achieve convergence toward input elastic properties. Furthermore, the obtained optimized parameters were used to simulate a series of plane strain compression tests on geomaterials to gain insight into plastic deformation and shear band formation. The study affirmed that parameter calibration is fundamental for accurately capturing both elastic and plastic behaviors of geomaterials. This calibrated model can offer significant potential for modelling failure surfaces below foundations, behind a retaining wall, and on a slope.

Diversidad florística y factores agroclimáticos en los Montes de María en Colombia: una revisión de la literatura. Floristic diversity and agroclimatic factors in the Montes de María, Colombia: a literature review

Julio Olaya — Wed, 29 Oct 2025 01:47:33 +0100

The tropical dry forest (Bs-T) is one of the most fragile habitats in Colombia, threatened by deforestation, the expansion of poor agricultural and livestock practices, and the fragmentation of the ecosystem. In the Montes de María, which spans territories of the departments of Bolívar and Sucre, a remnant of Bs-T of great relevance is preserved due to its biological and sociocultural value. This article provides a review of the current knowledge of floristic diversity and the agroclimatic factors that condition its composition and distribution. Several studies are analyzed that expose the role of climatic seasonality, the richness of plant species, as well as the main warnings facing this ecosystem. On the other hand, advancements in conservation, restoration, and participation are examined, highlighting the need to combine science with local knowledge to strengthen the planning of its territorial viability. The collected information provides an important resource to verify the execution of existing environmental policies and allows for the search for elements that contribute to the protection of biodiversity in the context of climate change, and the weight that human activities impose on ecosystems and natural resources.

IberGIS v1. User’s start guide and tutorial. Iber-SWMM calculation module

Marcos Sanz-Ramos — Tue, 28 Oct 2025 17:12:34 +0100

Urban drainage systems are facing increasing challenges due to climate change, urban growth, and the need for more sustainable water management. To address these issues, the Digital DRAIN project has developed an open-source tool that integrates different models within a GIS environment to analyse the performance of drainage systems. The tool helps assess both water flows and pollution, while also supporting the design of sustainable solutions and adaptation strategies. Delivered as the QGIS plugin IberGIS, it provides an accessible framework to improve urban water management and enhance resilience against floods and environmental impacts.

Real-Time Detection of Authority-Bearing Constructions Under Strict Causal Masking

Agustin V. Startari — Tue, 28 Oct 2025 13:46:33 +0100

This datasheet defines a benchmark for real-time detection of authority-bearing constructions under strict causal masking, where models access only left context. It measures how accurately and quickly a system identifies linguistic signals of authority without future tokens. Authority-bearing constructions are treated as Type-0 productions within a regla compilada, binding syntactic and operational constraints to decisions. Three hypotheses guide the study: a compact causal detector with an authority lexicon can achieve reliable precision at low latency; performance depends on construction family and register rather than sentiment; limited buffers can improve stability without breaking causality. Multilingual datasets (English, Spanish, optional French, German, Portuguese) include transcripts, hearings, and policy texts segmented into token streams. Tasks involve streaming span detection and stance classification, evaluated at multiple latency checkpoints and causal budgets (b ∈ {32, 64, 128}). Metrics cover streaming F1, AUCL, and stability index.Baselines (oracle, lexicon-only, sentiment) and strict no-lookahead validation ensure isolation of causal effects. The benchmark shows how form, not intent, governs real-time authority recognition, enabling evaluation of models for compliance and human-in-the-loop systems without right-context access. Acknowledgment / Editorial Note This article is published with editorial permission from LeFortune Academic Imprint, under whose license the text will also appear as part of the upcoming book AI Syntactic Power and Legitimacy. The present version is an autonomous preprint, structurally complete and formally self-contained. No substantive modifications are expected between this edition and the print edition. LeFortune holds non-exclusive editorial rights for collective publication within the Grammars of Power series. Open access deposit on SSRN is authorized under that framework, if citation integrity and canonical links to related works (SSRN: 10.2139/ssrn.4841065, 10.2139/ssrn.4862741, 10.2139/ssrn.4877266) are maintained.

Study the Wear Resistance and Corrosion of Ni-P/ PTFE Composite Coatings Prepared by Electrodeposition Method

Zainab Wetwet — Mon, 27 Oct 2025 17:30:33 +0100

Coating is one of the effective ways to increase the corrosion resistance and wear of metallic substrates. Additionally, the composite coatings using nanoparticles can also further protect the substrate. In this study, using electrodeposition process and polytetrafluoroethylene (PTFE) particles (with concentrations of 10, 20 or 30 g /L), NiPTFE coatings were prepared and their corrosion and wear properties were investigated and compared with Ni-P coating. Using scanning electron microscopy (SEM) and X-ray diffraction (EDS) method, the surface morphology and elemental composition of the coatings were analyzed and finally, by using open circuit potential (OCP) techniques, electrochemical impedance spectroscopy (EIS) and TAFEL polarization techniques, the corrosion resistance of the resulting coatings in 3/5 wt.% NaCl solution were evaluated. Microhardness and pin on disk tests were also utilized to investigate the effect of PTFE concentration on the tribological properties of the coatings. The results of SEM and EDS studies confirmed the formation of nanocomposites. Electrochemical studies also showed that Ni-PTFE coatings, at a concentration of 20 g/L PTFE, had the highest electrochemical corrosion resistance. Microhardness also decreased with increasing PTFE particles in the coating and reached its lowest value. By using the wear test, the lowest coefficient of friction obtained in composite coatings with concentration of 20 g/L, which shows the applicability of PTFE particles as a solid lubricant in Ni-P coatings.

Level of Compliance of School Buildings on DepEd Order No. 6, S. 2021: A Basis for Policy Formulation

Emer T. Quezon — Sat, 25 Oct 2025 14:23:34 +0200

In developing educational infrastructure, adherence to regulatory standards is vital to ensuring safe, conducive learning environments. This study evaluated the compliance of public-school buildings in the DepEd Division of Tuguegarao with DepEd Order No. 6, s. 2021. Using both quantitative and qualitative approaches, researchers conducted actual observations with a structured tool patterned after the DepEd Order. They surveyed school physical facilities coordinators and school heads to measure awareness levels. Findings revealed varied levels of compliance across five building groups. Groups 1 and 3 recorded weighted means of 1.54 and 1.65, respectively, indicating non-compliance, whereas Groups 2 and 4 showed partial compliance, with weighted means of 1.68 and 1.83, respectively. Group 5 achieved better compliance with a mean of 2.57. Meanwhile, awareness levels among coordinators and school heads were high, ranging from 2.63 to 2.97. Interestingly, the study found significant negative correlations between compliance and awareness for non-donated buildings, particularly in stairways (-0.72871) and corridor railings (-0.68859). For donated buildings, however, little to no significant correlations were observed in classroom size, architectural features, plumbing, and structural components. Overall, the study highlights critical areas of non-compliance and the need for targeted improvements in school infrastructure.