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16 pages, 17057 KiB  
Article
Numerical Analysis of Cavitation Suppression on a NACA 0018 Hydrofoil Using a Surface Cavity
by Pankaj Kumar, Ebrahim Kadivar and Ould el Moctar
J. Mar. Sci. Eng. 2025, 13(8), 1517; https://doi.org/10.3390/jmse13081517 - 6 Aug 2025
Abstract
This study examines the hydrodynamic and acoustic performance of plain NACA0018 hydrofoil and modified NACA0018 hydrofoils (foil with a cavity on suction surface) at a Reynolds number (Re) of 40,000, which is indicative of small-scale turbines and [...] Read more.
This study examines the hydrodynamic and acoustic performance of plain NACA0018 hydrofoil and modified NACA0018 hydrofoils (foil with a cavity on suction surface) at a Reynolds number (Re) of 40,000, which is indicative of small-scale turbines and marine applications. A cavity was created on suction side surface at 40–50% of the chord length, which is chosen for its efficacy in cavitation control. The present analysis examines the impact of the cavity on lift-to-drag-ratio (L/D) and cavity length at three cavitation numbers (1.7, 1.2, and 0.93) for plain and modified hydrofoils. Simulations demonstrate a significant enhancement of 7% in the lift-to-drag ratio relative to traditional designed foils. Contrary to earlier observations, the cavity length increases instead of decreasing for the modified hydrofoil. Both periodic steady and turbulent inflow conditions are captured that simulate the complex cavity dynamics and flow–acoustic interactions. It is found that a reduction in RMS velocity with modified blade suggests flow stabilization. Spectral analysis using Mel-frequency techniques confirms the cavity’s potential to reduce low-frequency flow-induced noise. These findings offer new insights for designing quieter and more efficient hydrofoils and turbine blades. Full article
(This article belongs to the Section Ocean Engineering)
23 pages, 5280 KiB  
Article
Seismic Damage Pattern Analysis of Long-Span CFST Arch Bridges Based on Damper Configuration Strategies
by Bin Zhao, Longhua Zeng, Qingyun Chen, Chao Gan, Lueqin Xu and Guosi Cheng
Buildings 2025, 15(15), 2728; https://doi.org/10.3390/buildings15152728 - 2 Aug 2025
Viewed by 184
Abstract
Variations in damper configuration strategies have a direct impact on the seismic damage patterns of long-span deck-type concrete-filled steel tube (CFST) arch bridges. This study developed an analysis and evaluation framework to identify the damage category, state, and progression sequence of structural components. [...] Read more.
Variations in damper configuration strategies have a direct impact on the seismic damage patterns of long-span deck-type concrete-filled steel tube (CFST) arch bridges. This study developed an analysis and evaluation framework to identify the damage category, state, and progression sequence of structural components. The framework aims to investigate the influence of viscous dampers on the seismic response and damage patterns of long-span deck-type CFST arch bridges under near-fault pulse-like ground motions. The effects of different viscous damper configuration strategies and design parameters on seismic responses of long-span deck-type CFST arch bridges were systematically investigated, and the preferred configuration and parameter set were identified. The influence of preferred viscous damper configurations on seismic damage patterns of long-span deck-type CFST arch bridges was systematically analyzed through the established analysis and evaluation frameworks. The results indicate that a relatively optimal reduction in bridge response can be achieved when viscous dampers are simultaneously installed at both the abutments and the approach piers. Minimum seismic responses were attained at a damping exponent α = 0.2 and damping coefficient C = 6000 kN/(m/s), demonstrating stability in mitigating vibration effects on arch rings and bearings. In the absence of damper implementation, the lower chord arch foot section is most likely to experience in-plane bending failure. The piers, influenced by the coupling effect between the spandrel construction and the main arch ring, are more susceptible to damage as their height decreases. Additionally, the end bearings are more prone to failure compared to the central-span bearings. Implementation of the preferred damper configuration strategy maintains essentially consistent sequences in seismic-induced damage patterns of the bridge, but the peak ground motion intensity causing damage to the main arch and spandrel structure is significantly increased. This strategy enhances the damage-initiation peak ground acceleration (PGA) for critical sections of the main arch, while concurrently reducing transverse and longitudinal bending moments in pier column sections. The proposed integrated analysis and evaluation framework has been validated for its applicability in capturing the seismic damage patterns of long-span deck-type CFST arch bridges. Full article
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12 pages, 1018 KiB  
Article
Manufacturing Considerations in the Aerodynamic Design Process of Turbomachinery Components
by Christian Effen, Benedikt Riegel, Nicklas Gerhard, Stefan Henninger, Pascal Behrens genannt Wäcken, Peter Jeschke, Viktor Rudel and Thomas Bergs
Processes 2025, 13(8), 2363; https://doi.org/10.3390/pr13082363 - 24 Jul 2025
Viewed by 430
Abstract
This paper presents a CFD-based method for the aerodynamic design of a high-pressure compressor rotor blisk, taking into account manufacturing constraints. Focus is placed on the influence of geometric deviations caused by the dynamic constraints of the milling machine. Special attention is given [...] Read more.
This paper presents a CFD-based method for the aerodynamic design of a high-pressure compressor rotor blisk, taking into account manufacturing constraints. Focus is placed on the influence of geometric deviations caused by the dynamic constraints of the milling machine. Special attention is given to the leading edge region of the blade, where high curvature results in increased sensitivity in both aerodynamic behavior and manufacturability. The generic blisk geometry on which this study is based is characterized by an elliptical leading edge. For the optimization, the leading edge is described by Bézier curves that transition smoothly to the suction and pressure sides with continuous curvature and a non-dimensional length ratio. In steady-state RANS parameter studies, the length ratio is systematically varied while the chord length is kept constant. For the aerodynamic evaluation of the design’s key performance parameters such as blade pressure distribution, total pressure loss and compressor efficiency are considered. To evaluate the machine dynamics for a given design, compliance with the nominal feed rate and the deviation between the planned and actual tool tip positions were used as evaluation parameters. Compared to the reference geometry with an elliptical leading edge, the purely aerodynamic optimization achieved an isentropic efficiency improvement of +0.24 percentage points in the aerodynamic design point and a profile deviation improvement of 3 µm in the 99th quantile. The interdisciplinary optimization achieved an improvement of +0.20 percentage points and 30 µm, respectively. This comparative study illustrates the potential of multidisciplinary design approaches that balance aerodynamic performance goals with manufacturability via a novel approach for Design-to-Manufacture-to-Design. Full article
(This article belongs to the Section Manufacturing Processes and Systems)
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25 pages, 17002 KiB  
Article
Study on Hydrodynamic and Cavitation Characteristics of Two-Element Hydrofoil Systems for Fully Submerged Hydrofoil Craft: Influence Analysis of Key Geometric Parameters
by Meishen Yu, Hongyu Li, Yu Zhang, Qunhong Tian, Shaobo Yang, Zongsheng Wang and Weizhuang Ma
J. Mar. Sci. Eng. 2025, 13(7), 1378; https://doi.org/10.3390/jmse13071378 - 20 Jul 2025
Viewed by 295
Abstract
This study investigates the effects of key geometric parameters on the hydrodynamic and cavitation characteristics of two-element hydrofoil systems for fully submerged unmanned hydrofoil craft, aiming to solve their active stabilization problems. Using STARCCM+ software, the RANS method, and the SST k-ω turbulence [...] Read more.
This study investigates the effects of key geometric parameters on the hydrodynamic and cavitation characteristics of two-element hydrofoil systems for fully submerged unmanned hydrofoil craft, aiming to solve their active stabilization problems. Using STARCCM+ software, the RANS method, and the SST k-ω turbulence model, the research analyzes the impacts of flap deflection angle (α), main wing-to-flap chord ratio (c1/c2), and spacing (g). Results show that when the spacing is fixed, increasing the chord ratio reduces the lift and drag coefficients. When the chord ratio is fixed, increasing the spacing causes the lift and drag coefficients to first rise and then fall. With increasing flap deflection angle (α), cavitation intensifies, but it can be suppressed by increasing the chord ratio, reaching a minimum at g = 2.4%c1. The optimal configuration is c1/c2 = 1.5 and g = 2.4%c1, which can balance the lift–drag performance and anti-cavitation capability. This study provides a scientific basis for solving the active stabilization problems of fully submerged unmanned hydrofoil craft and insights for enhancing their seakeeping performance. Full article
(This article belongs to the Special Issue CFD Applications in Ship and Offshore Hydrodynamics 2nd Edition)
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17 pages, 4176 KiB  
Article
Drag Reduction and Efficiency Enhancement in Wide-Range Electric Submersible Centrifugal Pumps via Bio-Inspired Non-Smooth Surfaces: A Combined Numerical and Experimental Study
by Tao Fu, Songbo Wei, Yang Gao and Bairu Shi
Appl. Sci. 2025, 15(14), 7989; https://doi.org/10.3390/app15147989 - 17 Jul 2025
Viewed by 240
Abstract
Wide-range electric submersible centrifugal pumps (ESPs) are critical for offshore oilfields but suffer from narrow high-efficiency ranges and frictional losses under dynamic reservoir conditions. This study introduces bio-inspired dimple-type non-smooth surfaces on impeller blades to enhance hydraulic performance. A combined numerical-experimental approach was [...] Read more.
Wide-range electric submersible centrifugal pumps (ESPs) are critical for offshore oilfields but suffer from narrow high-efficiency ranges and frictional losses under dynamic reservoir conditions. This study introduces bio-inspired dimple-type non-smooth surfaces on impeller blades to enhance hydraulic performance. A combined numerical-experimental approach was employed: a 3D CFD model with the k-ω turbulence model analyzed oil–water flow (1:9 ratio) to identify optimal dimple placement, while parametric studies tested diameters (0.6–1.2 mm). Experimental validation used 3D-printed prototypes. Results revealed that dimples on the pressure surface trailing edge reduced boundary layer separation, achieving a 12.98% head gain and 8.55% efficiency improvement at 150 m3/d in simulations, with experimental tests showing an 11.5% head increase and 4.6% efficiency gain at 130 m3/d. The optimal dimple diameter (0.9 mm, 2% of blade chord) balanced performance and manufacturability, demonstrating that bio-inspired surfaces improve ESP efficiency. This work provides practical guidelines for deploying drag reduction technologies in petroleum engineering, with a future focus on wear resistance in abrasive flows. Full article
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12 pages, 1377 KiB  
Article
A Mid-Term Follow-Up in Patients with Symptomatic Moderate to Severe and Severe Degenerative Mitral Valve Regurgitation After Transapical NeoChord Implantation
by Argyro Kalompatsou, Dimitris Tousoulis, Yannis Dimitroglou, Eirini Beneki, Panagiotis Theofilis, Konstantinos Tsioufis, Constantina Aggeli and Vasilis Lozos
Biomedicines 2025, 13(7), 1751; https://doi.org/10.3390/biomedicines13071751 - 17 Jul 2025
Viewed by 257
Abstract
Background: The transapical off-pump NeoChord procedure is a recognized minimally invasive surgical approach for the treatment of severe degenerative mitral regurgitation. This study aims to report the initial Greek experience with the NeoChord procedure, presenting mid-term clinical and echocardiographic outcomes from a single [...] Read more.
Background: The transapical off-pump NeoChord procedure is a recognized minimally invasive surgical approach for the treatment of severe degenerative mitral regurgitation. This study aims to report the initial Greek experience with the NeoChord procedure, presenting mid-term clinical and echocardiographic outcomes from a single cardiothoracic surgical center, with a median follow-up duration of 20 months. Methods: In this study, 42 symptomatic patients with moderate to severe and severe primary mitral regurgitation underwent mitral valve repair with the Neochord procedure between March 2018 and December 2024. All patients were evaluated clinically and echocardiographically by the Heart team preoperatively, after 1 month, and at the last follow-up (end of 2024). The primary endpoint was established as the presence of a major clinical event (all-cause mortality, reintervention due to deterioration of MR, and cardiac-related rehospitalization). Results: The median age of patients was 69 [61.75–79.25] years, and 69% of patients were men. The median EuroScore II was 1.79 [1.32–2.48], and the STS-PROM MV repair score was 3.18 [2.28–4.66]. Regarding the preprocedural mitral valve anatomical evaluation, 35 patients had type A (83.3%),4 had type B(9.5%), whereas only two patients had type C and 1 with type D anatomy. The median of LAI was 1.2 [1.15–1.25], whereas the CI was 4 [2.15–5]. More than two neochordae were implanted in 34 patients (81%). MR severity improved at 1-month (<moderate:92.85%) and at the last follow-up (<moderate:92.1%). NYHA class decreased within 1 month (I + II: 95.23%) after the procedure and was maintained at the last follow-up (I + II: 94.73%). The median left ventricular ejection fraction (LVEF) before the procedure was 63 [58–67]%, which significantly decreased to 57 [53–61]% at the 1-month follow-up (2-sided p < 0.001). At the final follow-up, LVEF increased to 65 [60–68]%, however, this change was not statistically significant compared to the preprocedural value. During the follow-up period, four deaths were documented—three due to non-cardiac and one attributable to a cardiac cause. Two cases proceeded to reoperation for surgical valve implantation due to recurrent mitral valve regurgitation 6 months and 8 months after the NeoChord procedure. Conclusions: Transapical off-pump NeoChord implantation offers a minimally invasive alternative to conventional surgery for symptomatic patients with moderate-to-severe or severe primary mitral regurgitation. Among patients with suitable mitral valve anatomy, the procedure has demonstrated a favorable safety profile and promising mid-term outcomes, in terms of cardiac mortality, as well as freedom from reoperation and rehospitalization. Full article
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27 pages, 1734 KiB  
Article
Characterizing Wake Behavior of Adaptive Aerodynamic Structures Using Reduced-Order Models
by Kyan Sadeghilari, Aditya Atre and John Hall
Energies 2025, 18(14), 3648; https://doi.org/10.3390/en18143648 - 10 Jul 2025
Viewed by 338
Abstract
In recent times, blades that have the ability to change shape passively or actively have garnered interest due to their ability to optimize blade performance for varying flow conditions. Various versions of morphing exist, from simple chord length changes to full blade morphing [...] Read more.
In recent times, blades that have the ability to change shape passively or actively have garnered interest due to their ability to optimize blade performance for varying flow conditions. Various versions of morphing exist, from simple chord length changes to full blade morphing with multiple degrees of freedom. These blades can incorporate smart materials or mechanical actuators to modify the blade shape to suit the wind conditions. Morphing blades have shown an ability to improve performance in simulations. These simulations show increased performance in Region 2 (partial load) operating conditions. This study focuses on the effects of the wake for a flexible wind turbine with actively variable twist angle distribution (TAD) to improve the energy production capabilities of morphing structures. These wake effects influence wind farm performance for locally clustered turbines by extracting energy from the free stream. Hence, the development of better wake models is critical for better turbine design and controls. This paper provides an outline of some approaches available for wake modeling. FLORIS (FLow Redirection and Induction Steady-State) is a program used to predict steady-state wake characteristics. Alongside that, the Materials and Methods section shows different modeling environments and their possible integration into FLORIS. The Results and Discussion section analyzes the 20 kW wind turbine with previously acquired data from the National Renewable Energy Laboratory’s (NREL) AeroDyn v13 software. The study employs FLORIS to simulate steady-state non-linear wake interactions for the nine TAD shapes. These TAD shapes are evaluated across Region 2 operating conditions. The previous study used a genetic algorithm to obtain nine TAD shapes that maximized aerodynamic efficiency in Region 2. The Results and Discussion section compares these TAD shapes to the original blade design regarding the wake characteristics. The project aims to enhance the understanding of FLORIS for studying wake characteristics for morphing blades. Full article
(This article belongs to the Section A3: Wind, Wave and Tidal Energy)
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20 pages, 5814 KiB  
Article
The Effect of Inflatable Pressure on the Strain Deformation of Flexible Wing Skin Film
by Longbin Liu, Mengyang Fan and Xingfu Cui
Appl. Sci. 2025, 15(13), 7596; https://doi.org/10.3390/app15137596 - 7 Jul 2025
Viewed by 231
Abstract
Flexible inflatable film wings have many functional advantages that traditional fixed rigid wings do not possess, such as foldability, small size, light weight, convenient storage, transportation, and so on. More and more scholars and engineers are paying attention to flexible inflatable wings, which [...] Read more.
Flexible inflatable film wings have many functional advantages that traditional fixed rigid wings do not possess, such as foldability, small size, light weight, convenient storage, transportation, and so on. More and more scholars and engineers are paying attention to flexible inflatable wings, which have gradually become a new hot research topic. However, flexible wings rely on inflation pressure to maintain the shape and rigidity of the skin film, and the inflation pressure has a significant influence on the strain deformation and wing bearing characteristics of flexible wing skin film. Here, based on the flexible mechanics theory and balance principle of flexible inflatable film, a theoretical model of structural deformation and internal inflation pressure was constructed, and finite element simulation analysis under different internal inflation pressure conditions was carried out as well. The results demonstrate that the biaxial deformation of flexible wing skin film is closely related to internal inflation pressure, local size, configuration, and film material properties. However, strain deformation along the wingspan direction is quite distinguishing, skin films work under the condition of biaxial plane deformation, and the strain deformation of the spanning direction is obviously higher than that of the chord direction, which all increases with internal inflation pressure. Therefore, it is necessary to pay more attention to bearing strain deformation characteristics to meet the bearing stiffness requirements, which could effectively provide a theoretical reference for the structural optimization design and inflation scheme setting of flexible inflatable wings. Full article
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17 pages, 1279 KiB  
Article
The Impact of Adjuvant Chemotherapy on Clinical Outcomes in Locally Advanced Rectal Cancer: A CHORD Consortium Analysis
by Kaveh Farrokhi, Horia Marginean, Anas Al Ghamdi, Essa Al Mansor, Shaan Dudani, Rachel A. Goodwin, Timothy R. Asmis, Erin Powell, Patricia A. Tang, Richard Lee-Ying and Michael M. Vickers
Curr. Oncol. 2025, 32(7), 371; https://doi.org/10.3390/curroncol32070371 - 26 Jun 2025
Viewed by 461
Abstract
Background: The impact of adjuvant chemotherapy (AC) on outcomes in real-world patients with locally advanced rectal cancer (LARC) remains uncertain. Methods: Consecutive patients with LARC (stage II/III) undergoing neoadjuvant chemoradiation before curative-intent surgery from 2005 to 2013 were identified in the Canadian Health [...] Read more.
Background: The impact of adjuvant chemotherapy (AC) on outcomes in real-world patients with locally advanced rectal cancer (LARC) remains uncertain. Methods: Consecutive patients with LARC (stage II/III) undergoing neoadjuvant chemoradiation before curative-intent surgery from 2005 to 2013 were identified in the Canadian Health Outcomes Research Database. The impact of AC on clinical outcomes, including disease-free survival (DFS) and overall survival (OS), was evaluated using the Kaplan–Meier method and Cox proportional hazards modeling. Results: A total of 1448 patients had sufficient data available to be included for analysis with 1085 (74.9%) receiving AC. Of AC patients, 40.5% received oxaliplatin-based treatments. With a median follow-up of 66.43 months, the 5-year DFS rate was 67.7% (95% CI: 64.5–70.1%) vs. 58.7% (95% CI: 52.8–64.2%) in the AC group and non-AC group, respectively (p < 0.001). The 5-year OS rate of the whole cohort was 74.3% (95% CI: 71.5–76.85%) while the 5-year OS rate of the AC group was 77.8% (95% CI: 74.7–80.6%) compared with 63.8% (95% CI: 57.9–69.2%) for the non-AC group (p < 0.001). On multivariate analysis, patients who received AC had improved DFS (HR 0.6, 95% CI: 0.49–0.73, p < 0.001) and OS (HR 0.46, 95% CI: 0.36–0.58, p < 0.001). Conclusions: This large multi-institutional database analysis supports the use of AC in real-world LARC patients treated with nCRT followed by surgical resection. Full article
(This article belongs to the Section Gastrointestinal Oncology)
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23 pages, 2927 KiB  
Article
Innovative Suspension Structures: The Role of Straight Elements Under Asymmetric Loads
by Algirdas Juozapaitis and Alfonsas Daniūnas
Appl. Sci. 2025, 15(13), 7009; https://doi.org/10.3390/app15137009 - 21 Jun 2025
Cited by 1 | Viewed by 225
Abstract
Suspension structures, known for their excellent properties, have been widely used to cover medium and large spans. Their efficiency lies in their ability to primarily withstand permanent and variable loads through tension. Consequently, suspension roof structures typically adopt a parabolic shape, which remains [...] Read more.
Suspension structures, known for their excellent properties, have been widely used to cover medium and large spans. Their efficiency lies in their ability to primarily withstand permanent and variable loads through tension. Consequently, suspension roof structures typically adopt a parabolic shape, which remains in equilibrium under symmetric loads. However, when subjected to asymmetric loads, such structures experience significant kinematic displacements. To reduce these displacements, suspension systems with bending stiffness, commonly referred to as “rigid” cables, are employed. Such elements increase the sustainability of the suspension system compared with conventional spiral ropes. Although previous studies have analyzed the behavior of such systems under symmetric loads, this article examines the performance of an innovative cable–strut system composed of straight “rigid” elements under asymmetric loads. The behavior of three different types of suspension structures under asymmetric loads is analyzed. A non-linear analysis of forces and displacements is conducted in this system, assessing the impact of bending stiffness on the structural response. The results indicate that the proposed two-level suspension system performs more effectively under asymmetric loads than both conventional parabolic suspension structures and suspension systems comprising two straight “rigid” elements. It was found that the total forces and stresses in the “rigid” upper chord elements of the two-level system are the lowest among all the systems considered. Therefore, this system is particularly suitable for covering medium- and large-span roofs, especially when subjected to relatively large asymmetric loads. Full article
(This article belongs to the Special Issue Recent Advances in Sustainable Construction Materials and Structures)
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25 pages, 1224 KiB  
Article
Generative Jazz Chord Progressions: A Statistical Approach to Harmonic Creativity
by Adriano N. Raposo and Vasco N. G. J. Soares
Information 2025, 16(6), 504; https://doi.org/10.3390/info16060504 - 17 Jun 2025
Viewed by 991
Abstract
Jazz music has long been a subject of interest in the field of generative music. Traditional jazz chord progressions follow established patterns that contribute to the genre’s distinct sound. However, the demand for more innovative and diverse harmonic structures has led to the [...] Read more.
Jazz music has long been a subject of interest in the field of generative music. Traditional jazz chord progressions follow established patterns that contribute to the genre’s distinct sound. However, the demand for more innovative and diverse harmonic structures has led to the exploration of alternative approaches in music generation. This paper addresses the challenge of generating novel and engaging jazz chord sequences that go beyond traditional chord progressions. It proposes an unconventional statistical approach, leveraging a corpus of 1382 jazz standards, which includes key information, song structure, and chord sequences by section. The proposed method generates chord sequences based on statistical patterns extracted from the corpus, considering a tonal context while introducing a degree of unpredictability that enhances the results with elements of surprise and interest. The goal is to move beyond conventional and well-known jazz chord progressions, exploring new and inspiring harmonic possibilities. The evaluation of the generated dataset, which matches the size of the learning corpus, demonstrates a strong statistical alignment between distributions across multiple analysis parameters while also revealing opportunities for further exploration of novel harmonic pathways. Full article
(This article belongs to the Special Issue Feature Papers in Information in 2024–2025)
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19 pages, 3072 KiB  
Article
Ground Clearance Effects on the Aerodynamic Loading of Tilted Flat Plates in Tandem
by Dimitrios Mathioulakis, Nikolaos Vasilikos, Panagiotis Kapiris and Christina Georgantopoulou
Fluids 2025, 10(6), 155; https://doi.org/10.3390/fluids10060155 - 12 Jun 2025
Viewed by 466
Abstract
The aerodynamic loading of four as well as of six tilted flat plates-panels arranged in tandem and in close proximity to the ground is examined through force and pressure measurements. In the four-plate set up, conducted in an open-circuit wind tunnel, a movable [...] Read more.
The aerodynamic loading of four as well as of six tilted flat plates-panels arranged in tandem and in close proximity to the ground is examined through force and pressure measurements. In the four-plate set up, conducted in an open-circuit wind tunnel, a movable floor is used to vary the ground clearance, and a one-component force balance is employed to measure the drag coefficient Cd of each plate for tilt angles 10° to 90° and for two head-on wind directions, 0° and 180°. An increase in the ground clearance from 20% to 60% of the plates’ chord length, results in a Cd increase of over 40% in the downstream plates, and up to 20% in the leading one. For tilt angles below 40°, the drag on the first plate is up to 25% higher under the 180° wind direction compared to the opposite direction. Pressure distributions are also presented on a series of six much larger plates, examined in a closed-circuit wind tunnel at tilt angles ±30°. While the windward surfaces exhibit relatively uniform pressure distributions, regions of low pressure develop on their suction side, near the plates’ tips leading edge, tending to become uniform streamwise. Full article
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19 pages, 3279 KiB  
Article
Data-Driven Prediction of Crystal Size Metrics Using LSTM Networks and In Situ Microscopy in Seeded Cooling Crystallization
by Ivan Vrban, Nenad Bolf and Josip Budimir Sacher
Processes 2025, 13(6), 1860; https://doi.org/10.3390/pr13061860 - 12 Jun 2025
Viewed by 533
Abstract
This work presents a data-driven modeling framework for predicting image-derived crystal size metrics in seeded cooling crystallization using Long Short-Term Memory (LSTM) neural networks. The model leverages in situ microscopy data to predict square-weighted D10, D50, D90, and particle counts based solely on [...] Read more.
This work presents a data-driven modeling framework for predicting image-derived crystal size metrics in seeded cooling crystallization using Long Short-Term Memory (LSTM) neural networks. The model leverages in situ microscopy data to predict square-weighted D10, D50, D90, and particle counts based solely on seed loading and temperature profiles, without requiring real-time supersaturation measurements. To enhance predictive power, engineered process descriptors—including temperature derivatives and integrals—were incorporated as dynamic features. Experimental validation was performed using creatine monohydrate crystallization from aqueous solution, with LSTM models trained on a diverse dataset encompassing variable seed loadings and cooling profiles. The feature-engineered LSTM model consistently outperformed its non-engineered counterpart, particularly under nonlinear cooling conditions where crystallization dynamics were the most complex. This approach offers a practical alternative to mechanistic models and spectroscopic process analytical technology (PAT) tools by enabling accurate prediction of chord length distribution (CLD) metrics from routinely collected data. The framework is easily transferable to other crystallization systems and provides a low-complexity, high-accuracy tool for accelerating lab-scale crystallization development. Full article
(This article belongs to the Special Issue Industrial Applications of Modeling Tools)
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22 pages, 3451 KiB  
Article
LSTM-Based Music Generation Technologies
by Yi-Jen Mon
Computers 2025, 14(6), 229; https://doi.org/10.3390/computers14060229 - 11 Jun 2025
Viewed by 643
Abstract
In deep learning, Long Short-Term Memory (LSTM) is a well-established and widely used approach for music generation. Nevertheless, creating musical compositions that match the quality of those created by human composers remains a formidable challenge. The intricate nature of musical components, including pitch, [...] Read more.
In deep learning, Long Short-Term Memory (LSTM) is a well-established and widely used approach for music generation. Nevertheless, creating musical compositions that match the quality of those created by human composers remains a formidable challenge. The intricate nature of musical components, including pitch, intensity, rhythm, notes, chords, and more, necessitates the extraction of these elements from extensive datasets, making the preliminary work arduous. To address this, we employed various tools to deconstruct the musical structure, conduct step-by-step learning, and then reconstruct it. This article primarily presents the techniques for dissecting musical components in the preliminary phase. Subsequently, it introduces the use of LSTM to build a deep learning network architecture, enabling the learning of musical features and temporal coherence. Finally, through in-depth analysis and comparative studies, this paper validates the efficacy of the proposed research methodology, demonstrating its ability to capture musical coherence and generate compositions with similar styles. Full article
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10 pages, 304 KiB  
Article
On the Relation Between a Locus and Poncelet’s Closure Theorem
by Jiří Blažek
Geometry 2025, 2(2), 8; https://doi.org/10.3390/geometry2020008 - 9 Jun 2025
Viewed by 491
Abstract
This article contains a synthetic proof of the following proposition: consider a conic c1 and its variable chord AB, which subtends a right angle at a given point P. Then, the foot E of the perpendicular dropped from P [...] Read more.
This article contains a synthetic proof of the following proposition: consider a conic c1 and its variable chord AB, which subtends a right angle at a given point P. Then, the foot E of the perpendicular dropped from P onto the line AB lies on a certain circle (the line being the limiting case of the circle). To prove this proposition, we show how Poncelet’s closure theorem for quadrilaterals can be derived by elementary projective considerations only (without any computations, either in Cartesian or projective coordinates). Finally, the limiting case of the proposition, where the point P lies on the conic, is also mentioned. The problem can then be reduced to Frégier’s theorem and may represent a slightly different perspective on this theorem. Full article
(This article belongs to the Special Issue Feature Papers in Geometry)
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