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16 pages, 265 KB  
Entry
Wage-Setting Institutions and Wage
by Georgios Giotis
Encyclopedia 2025, 5(4), 191; https://doi.org/10.3390/encyclopedia5040191 (registering DOI) - 7 Nov 2025
Definition
This entry examines how wage-setting institutions (WSIs) shape wages across advanced economies. It focuses on four core mechanisms—minimum wages, collective bargaining, wage coordination, and wage centralization—drawing on theoretical insights, empirical evidence, and cross-country comparisons. The analysis shows that minimum wages safeguard low-paid workers [...] Read more.
This entry examines how wage-setting institutions (WSIs) shape wages across advanced economies. It focuses on four core mechanisms—minimum wages, collective bargaining, wage coordination, and wage centralization—drawing on theoretical insights, empirical evidence, and cross-country comparisons. The analysis shows that minimum wages safeguard low-paid workers but have heterogeneous employment effects depending on their level and enforcement. Collective bargaining raises average wages and compresses wage inequality, though it can reduce flexibility and create insider–outsider dynamics. Wage coordination stabilizes wage growth, prevents inflationary spirals, and fosters equity, while wage centralization promotes solidarity wages and macroeconomic discipline but may limit adaptability. Using The Organization for Economic Co-operation and Development (OECD) and Institutional Characteristics of Trade Unions, Wage Setting, State Intervention and Social Pacts (ICTWSS) data, the study highlights institutional diversity, ranging from coordinated Nordic models to fragmented liberal systems, and identifies trends toward “organized decentralization.” Policy implications suggest that WSIs should be viewed not as rigidities but as adaptable frameworks that can balance efficiency, equity, and stability when carefully designed. The conclusion emphasizes that the future of wage-setting lies in leveraging institutional complementarities to respond to globalization, technological change, and shifting labor market conditions. Full article
(This article belongs to the Section Social Sciences)
14 pages, 581 KB  
Article
Entrepreneurial Literacy and Financial Behavior Among Indonesian Mompreneurs: Insights from a Knowledge-Based Innovation Perspective
by Fajriani Azis, Thamrin Tahir, Masnawaty S, Muhammad Azis and Muhammad Hasan
J. Risk Financial Manag. 2025, 18(11), 622; https://doi.org/10.3390/jrfm18110622 - 7 Nov 2025
Abstract
This study aims to develop an entrepreneurial literacy model for mompreneurs that contributes to Sustainable Development Goal (SDG) 1 (poverty reduction) and Sustainable Development Goal (SDG) 8 (decent work and economic growth), focusing on how entrepreneurial literacy transforms into financial behavior and fosters [...] Read more.
This study aims to develop an entrepreneurial literacy model for mompreneurs that contributes to Sustainable Development Goal (SDG) 1 (poverty reduction) and Sustainable Development Goal (SDG) 8 (decent work and economic growth), focusing on how entrepreneurial literacy transforms into financial behavior and fosters innovation in micro-business management. A qualitative case study was conducted in several districts of Makassar City, Indonesia. Participants were selected based on their status as mompreneurs and their type of business. Data were collected through in-depth interviews, observations, and documentation, then analyzed using a thematic spiral model. Entrepreneurial literacy, obtained through formal and informal education, translates into financial behaviors such as basic planning, financial management, and reporting. Innovation emerges through improved creativity, marketing, customer relationships, product development, and service enhancement. This study proposes a conceptual model linking entrepreneurial literacy, financial behavior, and innovation, offering insights for developing training programs that empower women in entrepreneurship. The scope of this study is limited to mompreneurs operating micro-scale businesses in Makassar City; therefore, the findings cannot be generalized to different socio-economic contexts. Nevertheless, the results provide theoretical implications for enriching entrepreneurial literacy models from an accounting perspective and practical implications for policymakers to design gender-responsive entrepreneurship and financial literacy programs. Full article
(This article belongs to the Special Issue Behavioral Finance and Financial Management)
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17 pages, 4113 KB  
Article
Influence of Random Corrosion on the Surface of Rock Bolts on the Propagation Characteristics of Ultrasonic Guided Waves: Taking Corrosion Depth and Area Ratio as Variables
by Manman Wang, Qianjin Zou, Haigang Li and Wen He
Buildings 2025, 15(21), 4009; https://doi.org/10.3390/buildings15214009 - 6 Nov 2025
Abstract
Corrosion of rock bolts in engineering exhibits random spatial distribution characteristics. To elucidate the influence mechanism of stochastic corrosion on the surface of rock bolts on the propagation behavior of ultrasonic guided waves, this study establishes a finite element model of rock bolts [...] Read more.
Corrosion of rock bolts in engineering exhibits random spatial distribution characteristics. To elucidate the influence mechanism of stochastic corrosion on the surface of rock bolts on the propagation behavior of ultrasonic guided waves, this study establishes a finite element model of rock bolts that incorporates stochastic corrosion characteristics. The coupled effects of corrosion depth and area ratio on guided wave propagation characteristics, time-domain response, energy distribution, and wave velocity variation are systematically investigated. Results indicate that corrosion depth and area ratio synergistically deteriorate guided wave morphology, transforming the stress field from symmetric and uniform to asymmetric and spiral. Reflections, scattering, and mode conversion induced by defects lead to a significant increase in the attenuation rate of pulse amplitude, with the two parameters governing the vertical interaction intensity and horizontal interference scope, respectively. Analysis of the Hilbert curve reveals that corrosion characteristics disrupt energy concentration. Under constant corrosion depth, an increase in area ratio disperses energy toward delayed scattered waves, while under constant area ratio, greater corrosion depth reduces the peak amplitude of the envelope curve. Overall, the energy integral exhibits an increasing trend with the degree of corrosion, whereas the peak-to-peak wave velocity shows a declining trend. The established multivariate nonlinear model accurately describes the coupled influence of corrosion parameters on wave velocity. This stochastic corrosion model overcomes the limitations of traditional simplified models and provides critical theoretical support for parameter calibration and engineering application of ultrasonic guided wave technology in the quantitative assessment of rock bolt corrosion. Full article
(This article belongs to the Section Building Structures)
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16 pages, 3938 KB  
Article
Comparative Study of Water Absorption and Dimensional Stability Between Bamboo Nodes and Internodes
by Na Su, Zonglin Li, Qingqing Yan, Yiwen Chen and Haocheng Xu
Forests 2025, 16(11), 1685; https://doi.org/10.3390/f16111685 - 5 Nov 2025
Abstract
Bamboo often suffers from moisture-induced cracking, in which the structural and dimensional differences between nodes and internodes may be key contributing factors. Taking Phyllostachys edulis (Carrière) J. Houz. as an example, this study systematically examined the water absorption behavior and dimensional stability of [...] Read more.
Bamboo often suffers from moisture-induced cracking, in which the structural and dimensional differences between nodes and internodes may be key contributing factors. Taking Phyllostachys edulis (Carrière) J. Houz. as an example, this study systematically examined the water absorption behavior and dimensional stability of bamboo nodes and internodes, and further analyzed their pore structure and chemical composition to provide a comprehensive understanding of their moisture response. This study systematically compared nodes and internodes of Phyllostachys edulis in water absorption behavior, dimensional stability, pore architecture, and vascular structure. Results showed that internodes exhibited higher water absorption rates and capacities in both short- and long-term tests, whereas nodes displayed lower water uptake and were prone to cracking during drying, indicating reduced dimensional stability. Anatomical and infrared analyses revealed that diaphragms, transverse vascular bundles, and spiral networks in nodes increased fluid path tortuosity, reducing longitudinal permeability. Pore structure analysis further indicated that internodes contained abundant pores facilitating rapid liquid transport, while node pores were mainly medium to large, favoring liquid retention but limiting permeability. Higher cellulose crystallinity and lignin content in nodes enhanced hydrophobicity, further restricting water penetration. Additionally, the complex fiber orientation in nodes induced anisotropic swelling and internal stress, increasing the risk of twisting and cracking. This multi-scale investigation elucidates the structural and compositional mechanisms underlying the observed differences in water absorption behavior and dimensional stability between nodes and internodes. These findings offer valuable insights for improving the moisture resistance, dimensional stability, and overall performance of bamboo materials in engineered applications, and provide a solid foundation for their targeted modification and optimization. Full article
(This article belongs to the Section Forest Ecophysiology and Biology)
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17 pages, 1413 KB  
Article
Secondhand Smoke Exposure Timing Triggers Distinct Placental Responses in Mouse Pregnancy
by Archarlie Chou, Ethan Frank, Matt Reall, Olivia Hiatt, Logan Beck, Paul R. Reynolds, Brett E. Pickett and Juan A. Arroyo
Cells 2025, 14(21), 1735; https://doi.org/10.3390/cells14211735 - 5 Nov 2025
Viewed by 41
Abstract
Secondhand smoke (SHS), found in about 57.6% of global public areas as a widespread environmental hazard, has been associated with negative effects during pregnancy, such as preeclampsia (PE) and intrauterine growth restriction (IUGR). Our research investigated the impact of SHS on placental issues [...] Read more.
Secondhand smoke (SHS), found in about 57.6% of global public areas as a widespread environmental hazard, has been associated with negative effects during pregnancy, such as preeclampsia (PE) and intrauterine growth restriction (IUGR). Our research investigated the impact of SHS on placental issues in a C57BL/6 model that simulates PE and IUGR in mice. We administered SHS to pregnant mice through a nose-only delivery method, beginning either on embryonic day 12.5 (prior to spiral artery (SA) invasion; labeled SHS-6D) or day 14.5 (following SA invasion; labeled SHS-4D), continuing up to E18.5. Control animals received only ambient air. We employed bulk RNA sequencing to assess and describe changes in placental gene expression patterns. For the SHS-4D group, which mimicked IUGR, compared to untreated controls, results showed elevated levels of inflammation-related genes (IL11RA, CHI3L1) alongside likely interference in pathways for antibody-triggered complement activation, marked by reduced expression of C1QA, C1QB, and C1QC. Immune profiling also indicated decreased macrophage activity in the placentas of the SHS-4D group relative to those from normal pregnancies at term. In contrast, the SHS-6D versus control analysis revealed lowered expression of collagen-related genes (COL1A1, COL4A5, COL4A6, COL17A1). Additionally, SHS-6D exhibited higher levels of genes associated with cell-based lysis processes compared to SHS-4D. An evaluation of the existing literature revealed that nearly every differentially expressed gene (DEG) identified in our work has been reported in studies associated with SHS exposure. Yet, few of these DEGs are discussed alongside PE or IUGR in prior reports, highlighting gaps in knowledge about how SHS triggers these conditions. Overall, we determined that the timing of SHS exposure in pregnant mice results in unique patterns of gene regulation and involvement in biological pathways. Full article
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25 pages, 4039 KB  
Article
A Deep Learning Framework for Early Parkinson’s Disease Detection: Leveraging Spiral and Wave Handwriting Tasks with EfficientNetV2-S
by Ayesha Razaq, Shabana Ramzan, Sohail Jabbar, Muhammad Munwar Iqbal, Muhammad Asif Habib and Umar Raza
Diagnostics 2025, 15(21), 2795; https://doi.org/10.3390/diagnostics15212795 - 4 Nov 2025
Viewed by 92
Abstract
Background: Early detection of Parkinson’s disease (PD) is vital for improving patient outcomes, yet traditional diagnostic methods often depend on subjective clinical evaluations. Methods: This study proposes a novel deep learning framework for PD detection based on spiral and wave handwriting patterns from [...] Read more.
Background: Early detection of Parkinson’s disease (PD) is vital for improving patient outcomes, yet traditional diagnostic methods often depend on subjective clinical evaluations. Methods: This study proposes a novel deep learning framework for PD detection based on spiral and wave handwriting patterns from the PaHaW dataset. A comprehensive preprocessing pipeline is implemented, integrating histogram equalization and Canny edge detection. The processed spiral and wave images are evaluated independently using a fine-tuned EfficientNetV2-S architecture for binary classification. In addition to the EfficientNetV2-S experiments, a baseline Convolutional Neural Network (CNN) model is implemented separately for the spiral and wave handwriting images. The proposed model is further assessed using a 5-fold cross-validation strategy to ensure robustness and generalizability. Results: The models achieved validation accuracies of 98.68% on the spiral dataset and 98.10% on the wave dataset, with high Receiver Operating Characteristic–Area Under the Curve (ROC–AUC) scores, indicating robust discrimination between healthy and PD subjects. Analysis of the confusion matrix and classification results confirmed consistent sensitivity and specificity across the dataset. The 5-fold cross-validation yielded a standard deviation of ±0.0109. Conclusions: These results highlight the strong potential of handwriting analysis for early PD detection. Full article
(This article belongs to the Section Machine Learning and Artificial Intelligence in Diagnostics)
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18 pages, 5007 KB  
Article
Response and Flow Characteristics of an Angular Momentum Flowmeter
by Hao Zan, Qiusheng Jia, Chengli Liu, Jiabao Liu, Fuji Huang and Shenmei Zhou
Sensors 2025, 25(21), 6728; https://doi.org/10.3390/s25216728 - 3 Nov 2025
Viewed by 220
Abstract
The angular momentum flowmeter addresses critical challenges in aviation fuel flow measurement during commercial flight operations. This study designed a visualization platform to observe the dynamic responses of internal components under varying flow conditions. By employing the sliding mesh method coupled with an [...] Read more.
The angular momentum flowmeter addresses critical challenges in aviation fuel flow measurement during commercial flight operations. This study designed a visualization platform to observe the dynamic responses of internal components under varying flow conditions. By employing the sliding mesh method coupled with an angular momentum algorithm, it enabled the dynamic rotation simulation of the upstream straight-bladed rotor and provided calculation of the deflection angle in the downstream straight-bladed rotor of an angular momentum flowmeter. Experimental results categorize the flow process into three distinct regimes based on flat and spiral spring response states: pre-spring, single-spring, and dual-spring regimes. Under a flow condition of 0.091 kg/s, the upstream straight-bladed rotor maintained stable rotation at a speed of 1.1 rad/s. At a flow rate of 0.20 kg/s, the flat spring initiated outward expansion, and with further increase in flow rate, the rotational speed of the upstream straight-bladed rotor remained within the range of 25.34–26.21 rad/s. Mathematical analysis demonstrates that the flat spring configuration extends the lower measurement limit and promotes dissipation of the secondary vortex through dominant kinetic energy of the primary vortex during dual-spring operation, thereby improving high-pressure zone stability. This work elucidates the operational mechanism of angular momentum flowmeters and provides a theoretical basis for structural optimization. Full article
(This article belongs to the Collection Instrument and Measurement)
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30 pages, 19955 KB  
Article
Adaptive Sampling of Marine Submesoscale Features Using Gaussian Process Regression with Unmanned Platforms
by Wenbo Wang, Haibo Tang, Wei Song, Shuangshuang Fan and Dongxiao Wang
J. Mar. Sci. Eng. 2025, 13(11), 2088; https://doi.org/10.3390/jmse13112088 - 3 Nov 2025
Viewed by 208
Abstract
Submesoscale processes, characterized by strong vertical velocities that generate sea surface temperature (SST) fronts as well as O(1) Rossby number (Ro), are critical to ocean mixing and biogeochemical transport, yet their observation is hampered by cost and spatial limitations. Hence, this study [...] Read more.
Submesoscale processes, characterized by strong vertical velocities that generate sea surface temperature (SST) fronts as well as O(1) Rossby number (Ro), are critical to ocean mixing and biogeochemical transport, yet their observation is hampered by cost and spatial limitations. Hence, this study proposes an adaptive sampling framework for unmanned surface vehicles (USVs) that integrates Gaussian process regression (GPR) with submesoscale physical characteristics for efficient, targeted sampling. Three composite-kernel GPR models are developed to predict SST, zonal velocity U, and meridional velocity V, providing predictive fields to support adaptive path planning. A robust coupled gradient indicator (CGI) is further introduced to identify SST frontal zones, where the maximum CGI values are used to select candidate waypoints. Connecting these waypoints yields adaptive paths aligned with frontal structures, while a Ro threshold (0.5–2) automatically triggers spiral-intensive sampling to collect more useful data. Simulation results show that the planned paths effectively capture SST gradient and submesoscale dynamics. The final environment reconstruction achieved the desired accuracy after model retraining, and deployment analysis informs optimal platform deployment. Overall, the proposed framework couples environmental prediction, adaptive path planning, and intelligent sampling, offering an effective strategy for advancing the observation of submesoscale ocean processes. Full article
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10 pages, 3539 KB  
Article
Cordyceps biarmica sp. nov., an Entomopathogenic Fungus from Boreal Forests of North European Russia
by Igor Kazartsev, Maria Gomzhina, Maxim Levchenko and Georgy Lednev
Diversity 2025, 17(11), 762; https://doi.org/10.3390/d17110762 - 1 Nov 2025
Viewed by 151
Abstract
The European part of Russia has been characterized by a remarkably low documented diversity of entomopathogenic fungi, particularly when compared to the high species richness recorded in the Russian Far East. This pattern has persisted through decades of primarily morphology-based studies, which require [...] Read more.
The European part of Russia has been characterized by a remarkably low documented diversity of entomopathogenic fungi, particularly when compared to the high species richness recorded in the Russian Far East. This pattern has persisted through decades of primarily morphology-based studies, which require critical reassessment using modern molecular methods. Here, we introduce a new species, Cordyceps biarmica, described from its asexual stage collected in the taiga of Arkhangelsk Oblast, representing a notable addition to the known diversity of the genus Cordyceps in the region. The fungus was isolated from a poorly preserved lepidopteran cocoon with pulvinate, unbranched conidiomata. Morphological features of its pure culture revealed an Isaria-like asexual morph characterized by solitary or verticillate phialides on a subspherical to subcylindrical base, bearing conidia in imbricate chains twisted in spirals. Multilocus phylogenetic analysis of a five-locus dataset (ITS, nrLSU, rpb1, rpb2, and tef1-α) was conducted using Maximum Likelihood and Bayesian Inference. The isolate was robustly placed within Cordyceps s.s., forming a distinct monophyletic lineage separate from other closely related well-supported taxa, including Cordyceps cateniannulata, C. exasperata, C. locastrae, C. polyarthra, C. sandindaengensis, and C. spegazzinii. Full article
(This article belongs to the Special Issue Fungal Diversity)
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18 pages, 2895 KB  
Article
Design and Simulation of NEPTUNE-R: A Solar-Powered Autonomous Hydro-Robot for Aquatic Purification and Oxygenation
by Mihaela Constantin, Mihnea Gîrbăcică, Andrei Mitran and Cătălina Dobre
Sustainability 2025, 17(21), 9711; https://doi.org/10.3390/su17219711 - 31 Oct 2025
Viewed by 224
Abstract
This study presents the design, modeling, and multi-platform simulation of NEPTUNE-R, a solar-powered autonomous hydro-robot developed for sustainable water purification and oxygenation. Mechanical design was performed in Fusion 360, trajectory optimization in MATLAB R2024a, and dynamic motion analysis in Roblox Studio, creating a [...] Read more.
This study presents the design, modeling, and multi-platform simulation of NEPTUNE-R, a solar-powered autonomous hydro-robot developed for sustainable water purification and oxygenation. Mechanical design was performed in Fusion 360, trajectory optimization in MATLAB R2024a, and dynamic motion analysis in Roblox Studio, creating a reproducible digital twin environment. The proposed path-planning strategies—Boustrophedon and Archimedean spiral—achieved full surface coverage across various lake geometries, with an average efficiency of 97.4% ± 1.2% and a 12% reduction in energy consumption compared to conventional linear patterns. The integrated Euler-based force model ensured stability and maneuverability under ideal hydrodynamic conditions. The modular architecture of NEPTUNE-R enables scalable implementation of photovoltaic panels and microbubble-based oxygenation systems. The results confirm the feasibility of an accessible, zero-emission platform for aquatic ecosystem restoration and contribute directly to Sustainable Development Goals (SDGs) 6, 7, and 14 by promoting clean water, renewable energy, and life below water. Future work will involve prototype testing and experimental calibration to validate the numerical findings under real environmental conditions. Full article
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12 pages, 3747 KB  
Article
Design of a Sub-6 GHz CMOS Power Amplifier with a High-Q Glass Transformer for Off-Chip Output-Matching Networks
by Jaeyong Lee, Jong-Min Yook, Jinho Yoo and Changkun Park
Electronics 2025, 14(21), 4261; https://doi.org/10.3390/electronics14214261 - 30 Oct 2025
Viewed by 163
Abstract
This paper investigates and evaluates a compact, high-Q glass transformer with a 3D spiral structure that offers low loss and high area efficiency. Furthermore, we designed a CMOS power amplifier (PA) with an output-matching network implemented using an off-chip high-Q glass transformer to [...] Read more.
This paper investigates and evaluates a compact, high-Q glass transformer with a 3D spiral structure that offers low loss and high area efficiency. Furthermore, we designed a CMOS power amplifier (PA) with an output-matching network implemented using an off-chip high-Q glass transformer to validate its operation. Two transformer types were developed: a five-port transformer with a center-tap and a four-port transformer without a center tap. The high-Q property of the transformer leads to low loss and tight coupling, as evidenced by an increase in maximum available gain (MAG). Compared with an integrated CMOS transformer, the high-Q transformer exhibits significantly lower loss while maintaining similar area and inductance, despite being an external component. A test PA comprising the CMOS PA and the off-chip transformer was evaluated with simulations and measurements, and it was also compared with a fully integrated PA at the simulation level to verify performance improvements. The proposed PA achieved a saturation power of 29.8 dBm, which was 1.7 dB higher than that of the fully integrated PA. The PAE also improved by 11 percentage points, from 32.1% to 43.1% in simulation. The results show substantial performance gains in simulation, while the total area increases only slightly. Measurements show the same trend as the simulations; with shorter bond-wire lengths, the measured results are expected to approach the simulated performance. These findings demonstrate the feasibility of an ultra-compact CMOS–off-chip hybrid PA that delivers high performance while maintaining a footprint comparable to that of a fully integrated PA, enabling applications in compact devices including mobile products. Full article
(This article belongs to the Special Issue Advances in Analog and RF Circuit Design)
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18 pages, 2682 KB  
Article
Spirally Coiled Tube Flocculators: A New Hydrodynamic Design for Water Treatment
by Danieli Soares de Oliveira, Maurício Sartori and Clainer Bravin Donadel
Modelling 2025, 6(4), 139; https://doi.org/10.3390/modelling6040139 - 30 Oct 2025
Viewed by 153
Abstract
The design of tubular flocculators has advanced in the pursuit of more efficient and compact water treatment systems. Helically coiled tube flocculators (HCTFs) are known for generating stable secondary flows and uniform hydrodynamic patterns after the development length. However, their constant geometry restricts [...] Read more.
The design of tubular flocculators has advanced in the pursuit of more efficient and compact water treatment systems. Helically coiled tube flocculators (HCTFs) are known for generating stable secondary flows and uniform hydrodynamic patterns after the development length. However, their constant geometry restricts the hydrodynamic variability required for optimized flocculation. This study introduces the spirally coiled tube flocculator (SCTF), characterized by a winding diameter that varies along its length. CFD simulations and laboratory-scale experiments compared HCTFs and SCTFs in terms of turbidity removal capacity, axial velocity profiles, secondary flows, streamlines, and global velocity gradients. The SCTF outperformed the HCTFs under all evaluated configurations, achieving up to 98.2% turbidity removal. The results emphasize the potential of spiral geometries to enhance process efficiency and highlight the need to reconsider hydrodynamic strategies in the design of tubular flocculators. Full article
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20 pages, 8413 KB  
Article
An Analytical and Numerical Study of Wear Distribution on the Combine Harvester Header Platform: Model Development, Comparison, and Experimental Validation
by Honglei Zhang, Zhong Tang, Liquan Tian, Tiantian Jing and Biao Zhang
Lubricants 2025, 13(11), 482; https://doi.org/10.3390/lubricants13110482 - 30 Oct 2025
Viewed by 321
Abstract
The header platform of a combine harvester is subjected to severe abrasive and corrosive wear from rice stalks and environmental factors, which significantly limits its service life and operational efficiency. Accurately predicting the complex distribution of this wear over time and across the [...] Read more.
The header platform of a combine harvester is subjected to severe abrasive and corrosive wear from rice stalks and environmental factors, which significantly limits its service life and operational efficiency. Accurately predicting the complex distribution of this wear over time and across the platform’s surface, however, remains a significant challenge. This paper, for the first time, systematically establishes a quantitative mapping relationship from “material motion trajectory” to “component wear profile” and introduces a novel method for time-sequence wear validation based on corrosion color gradients, providing a complete research paradigm to address this challenge. To this end, an analytical model based on rigid-body dynamics was first developed to predict the motion trajectory of a single rice stalk. Subsequently, a full-scale Discrete Element (DEM) model of the header platform–flexible rice stalk system was constructed. This model simulated the complex flow process of the rice population with high fidelity and was used to analyze the influence of key operating parameters (spiral auger rotational speed, cutting width) on wear distribution. Finally, real-world wear data were obtained through in situ mapping of a header platform after long-term service (1300 h) and multi-period (0–1600 h) image analysis. Through a three-way quantitative comparison among the theoretical trajectory, simulated trajectory, and the actual wear profile, the results indicate that the simulated and theoretical trajectories are in good agreement in terms of their macroscopic trends (Mean Squared Error, MSE, ranging from 0.4 to 6.2); the simulated and actual wear profiles exhibit an extremely high degree of geometric similarity, with the simulated wear area showing a 95.1% match to the actual measured area (Edit Distance: 0.14; Hamming Distance: 1). This research not only confirms that the flow trajectory of rice is the determining factor for the wear distribution on the header platform but, more importantly, the developed analytical and numerical methods offer a robust theoretical basis and effective predictive tools for optimizing the wear resistance and predicting the service life of the header platform, thereby demonstrating significant engineering value. Full article
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22 pages, 2601 KB  
Article
A Hybrid Modeling Approach for Performance Prediction of Fouled Spiral Fin-Tube Heat Exchanger
by Ying Yang, Tingting Jiang, Jiayi Liu, De Tang, Hongyang Tian, Jianguo Miao and Congying Deng
Modelling 2025, 6(4), 138; https://doi.org/10.3390/modelling6040138 - 30 Oct 2025
Viewed by 277
Abstract
Spiral finned tube heat exchangers are extensively used in petrochemical, power electronics, and metallurgical industries due to their high efficiency and compact design. However, fouling accumulation during operation significantly reduces heat transfer efficiency and increases pressure loss. This study develops a hybrid approach [...] Read more.
Spiral finned tube heat exchangers are extensively used in petrochemical, power electronics, and metallurgical industries due to their high efficiency and compact design. However, fouling accumulation during operation significantly reduces heat transfer efficiency and increases pressure loss. This study develops a hybrid approach integrating discrete element method (DEM), finite element analysis (FEA), and HTRI Xchanger Suite 7 software to correlate fouling thickness with thermal performance and establish a prediction model for tube-side outlet temperature under varying conditions. DEM simulations analyze dust deposition patterns and determine equivalent fouling thickness distribution. A fouling-integrated FE model then evaluates how fouling thickness affects both heat transfer and flow resistance coefficients. Through orthogonal experimental design considering fouling thickness, ambient temperature, and inlet air velocity, thermal resistance values calculated from FEA are imported into HTRI to predict outlet temperature. A random forest algorithm is subsequently employed to develop a multivariable prediction model. Validation conducted on a spiral finned tube heat exchanger at Chongqing Xiangguosi Underground Gas Storage Co., Ltd. (Chongqing, China) confirmed close agreement between simulated and actual fouling patterns. The maximum relative error of the predicted outlet temperatures on the testing dataset was 0.1869%, demonstrating the proposed method’s potential to support performance evaluation and operational optimization of fouled heat exchangers. Full article
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16 pages, 923 KB  
Article
Transcervical, Transabdominal and Transvaginal Chorionic Villus Sampling for Prenatal Diagnosis in Zagreb, Croatia: A Prospective Single-Operator Study on 5500 Cases
by Petra Podobnik, Tomislav Meštrović, Mario Podobnik, Ivan Bertović-Žunec, Igor Lončar, Kristian Kurdija, Dženis Jelčić, Zlata Srebreniković and Slava Podobnik-Šarkanji
Diagnostics 2025, 15(21), 2750; https://doi.org/10.3390/diagnostics15212750 - 30 Oct 2025
Viewed by 346
Abstract
Background/Objectives: Chorionic villus sampling (CVS) is a pivotal diagnostic tool for early prenatal detection of chromosomal and genetic abnormalities; however, the safety and diagnostic efficacy of different CVS approaches remain a subject of clinical interest. This monocentric study compares transcervical (TC-CVS), transabdominal [...] Read more.
Background/Objectives: Chorionic villus sampling (CVS) is a pivotal diagnostic tool for early prenatal detection of chromosomal and genetic abnormalities; however, the safety and diagnostic efficacy of different CVS approaches remain a subject of clinical interest. This monocentric study compares transcervical (TC-CVS), transabdominal (TA-CVS) and transvaginal (TV-CVS) techniques, focusing on procedure-related fetal loss and diagnostic yield. Methods: In this 15-year, single-operator prospective study, a total of 5500 women underwent CVS between 10 and 14 weeks of gestation at a single center. Sampling was performed via TA-CVS (n = 4500), TC-CVS (n = 850), or TV-CVS (n = 150). Outcomes assessed included fetal loss rates, sample adequacy, early complications and hemodynamic changes measured by Doppler ultrasound. A p-value < 0.05 (two-tailed) was considered statistically significant. Results: Spontaneous abortion rates were significantly lower following TA-CVS (0.18%; 8/4500) compared to TC-CVS (0.6%; 5/850) and TV-CVS (1.3%; 2/150) (χ2 = 24.56, p < 0.001). Post hoc pairwise analysis showed significantly lower fetal loss in TA-CVS compared to TC-CVS, but not between TA-CVS and TV-CVS. Cytogenetic abnormalities were detected in 220 cases (4.0%), and clinically significant copy number variants (CNVs) were confirmed in fetuses with major structural malformations. Five-year follow-up showed no diagnosed intellectual disability among assessed children. Optimal tissue weight (10–20 mg) was more frequent with TA-CVS (66.7%) than TC-CVS (35.3%) or TV-CVS (36.7%) (χ2 = 350.92, p < 0.001). In a Doppler subset (n = 400), uterine, spiral, and interplacental artery PI changes were non-significant; the umbilical (p = 0.032) and middle cerebral arteries (p < 0.001) showed transient PI reductions after sampling. Conclusions: Transabdominal CVS demonstrated the most favorable balance of safety and diagnostic quality, suggesting it should be the preferred first-line technique in early prenatal diagnosis. Standardized technique and operator training remain critical to optimize outcomes. Full article
(This article belongs to the Special Issue Diagnosis and Prognosis of Gynecological and Obstetric Diseases)
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