Sign in to use this feature.

Years

Between: -

Subjects

remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline

Journals

remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline

Article Types

Countries / Regions

remove_circle_outline
remove_circle_outline

Search Results (244)

Search Parameters:
Keywords = cluster and outlier analysis

Order results
Result details
Results per page
Select all
Export citation of selected articles as:
21 pages, 7802 KB  
Article
A Structure-Based Deep Learning Framework for Correcting Marine Natural Products’ Misannotations Attributed to Host–Microbe Symbiosis
by Xiaohe Tian, Chuanyu Lyu, Yiran Zhou, Liangren Zhang, Aili Fan and Zhenming Liu
Mar. Drugs 2026, 24(1), 20; https://doi.org/10.3390/md24010020 - 1 Jan 2026
Viewed by 476
Abstract
Marine natural products (MNPs) are a diverse group of bioactive compounds with varied chemical structures, but their biological origins are often misannotated due to complex host–microbe symbiosis. Propagated through public databases, such errors hinder biosynthetic studies and AI-driven drug discovery. Here, we develop [...] Read more.
Marine natural products (MNPs) are a diverse group of bioactive compounds with varied chemical structures, but their biological origins are often misannotated due to complex host–microbe symbiosis. Propagated through public databases, such errors hinder biosynthetic studies and AI-driven drug discovery. Here, we develop a structure-based workflow of origin classification and misannotation correction for marine datasets. Using CMNPD and NPAtlas compounds, we integrate a two-step cleaning strategy that detects label inconsistencies and filters structural outliers with a microbial-pretrained graph neural network. The optimized model achieves a balanced accuracy of 85.56% and identifies 3996 compounds whose predicted microbial origins contradict their Animalia labels. These putative symbiotic metabolites cluster within known high-risk taxa, and interpretability analysis reveal biologically coherent structural patterns. This framework provides a scalable quality-control approach for natural product databases and supports more accurate biosynthetic gene cluster (BGC) tracing, host selection, and AI-driven marine natural product discovery. Full article
(This article belongs to the Special Issue Chemoinformatics for Marine Drug Discovery)
Show Figures

Graphical abstract

16 pages, 2031 KB  
Article
Cooperative 4D Trajectory Prediction and Conflict Detection in Integrated Airspace
by Xin Ma, Linxin Zheng, Jiajun Zhao and Yuxin Wu
Algorithms 2026, 19(1), 32; https://doi.org/10.3390/a19010032 - 1 Jan 2026
Viewed by 237
Abstract
In order to effectively ensure the flight safety of unmanned aerial vehicles (UAVs) and effectively deal with the risk of integrated airspace operation, this study carried out a series of key technology exploration and verification. In terms of data processing, Density-based spatial clustering [...] Read more.
In order to effectively ensure the flight safety of unmanned aerial vehicles (UAVs) and effectively deal with the risk of integrated airspace operation, this study carried out a series of key technology exploration and verification. In terms of data processing, Density-based spatial clustering of applications with noise (DBSCAN) clustering method is used to preprocess the characteristics of UAV automatic dependent surveillance–broadcast (ADS-B) data, effectively purify the data from the source, eliminate the noise and outliers of track data in spatial dimension and spatial-temporal dimension, significantly improve the data quality and standardize the data characteristics, and lay a reliable and high-quality data foundation for subsequent trajectory analysis and prediction. In terms of trajectory prediction, the convolutional neural networks-bidirectional gated recurrent unit (CNN-BiGRU) trajectory prediction model is innovatively constructed, and the integrated intelligent calculation of ‘prediction-judgment’ is successfully realized. The output of the model can accurately and prospectively judge the conflict situation and conflict degree between any two trajectories, and provide core and direct technical support for trajectory conflict warning. In the aspect of conflict detection, the performance of the model and the effect of conflict detection are fully verified by simulation experiments. By comparing the predicted data of the model with the real track data, it is confirmed that the CNN-BiGRU prediction model has high accuracy and reliability in calculating the distance between aircraft. At the same time, the preset conflict detection method is used for further verification. The results show that there is no conflict risk between the UAV and the manned aircraft in integrated airspace during the full 800 s of terminal area flight. In summary, the trajectory prediction model and conflict detection method proposed in this study provide a key technical guarantee for the construction of an active and accurate integrated airspace security management and control system, and have important application value and reference significance for improving airspace management efficiency and preventing flight conflicts. Full article
Show Figures

Figure 1

20 pages, 9525 KB  
Article
Analysis of Economic Development Patterns and Driving Factors of Dianchi Lake Basin Based on Space–Time Cubes and Interpretable Machine Learning
by Shihua Li, Guoyou Zhang, Xiaoyan Wei, Heng Liu and Jisheng Xia
Land 2026, 15(1), 51; https://doi.org/10.3390/land15010051 - 27 Dec 2025
Viewed by 343
Abstract
Regional economic development serves as a crucial indicator of societal vitality and the efficiency of resource allocation. Nighttime light (NL) remote sensing data is a reliable reflection of regional economic activities, making it essential to analyze its spatiotemporal variations and influencing factors for [...] Read more.
Regional economic development serves as a crucial indicator of societal vitality and the efficiency of resource allocation. Nighttime light (NL) remote sensing data is a reliable reflection of regional economic activities, making it essential to analyze its spatiotemporal variations and influencing factors for economic growth. This study employs space–time cubes, incorporating hotspot and outlier analysis, to explore the dynamics of NL in the Dianchi Lake basin between 2000 and 2022, focusing on shifts in centroids, temporal patterns, and spatial clustering. Various machine learning models were tested, with the most effective model utilizing the SHAP algorithm to uncover the nonlinear relationships between explanatory variables and NL. The findings reveal that economic hotspots are predominantly concentrated around Dianchi Lake, exhibiting high–high spatial clustering, whereas cold spots are mainly distributed in the northern and southern regions and are characterized by low–low clustering. In addition, human activity indicators (GDP, road density, and population) and climatic factors (temperature and precipitation) are positively associated with economic development, while topographic factors (DEM and slope) show negative associations. Full article
Show Figures

Figure 1

21 pages, 3674 KB  
Article
scSelector: A Flexible Single-Cell Data Analysis Assistant for Biomedical Researchers
by Xiang Gao, Peiqi Wu, Jiani Yu, Xueying Zhu, Shengyao Zhang, Hongxiang Shao, Dan Lu, Xiaojing Hou and Yunqing Liu
Genes 2026, 17(1), 2; https://doi.org/10.3390/genes17010002 - 19 Dec 2025
Viewed by 484
Abstract
Background: Standard single-cell RNA sequencing (scRNA-seq) analysis workflows face significant limitations, particularly the rigidity of clustering-dependent methods that can obscure subtle cellular heterogeneity and the potential loss of biologically meaningful cells during stringent quality control (QC) filtering. This study aims to develop [...] Read more.
Background: Standard single-cell RNA sequencing (scRNA-seq) analysis workflows face significant limitations, particularly the rigidity of clustering-dependent methods that can obscure subtle cellular heterogeneity and the potential loss of biologically meaningful cells during stringent quality control (QC) filtering. This study aims to develop scSelector (v1.0), an interactive software toolkit designed to empower researchers to flexibly select and analyze cell populations directly from low-dimensional embeddings, guided by their expert biological knowledge. Methods: scSelector was developed using Python, relying on core dependencies such as Scanpy (v1.9.0), Matplotlib (v3.4.0), and NumPy (v1.20.0). It integrates an intuitive lasso selection tool with backend analytical modules for differential expression and functional enrichment analysis. Furthermore, it incorporates Large Language Model (LLM) assistance via API integration (DeepSeek/Gemini) to provide automated, contextually informed cell-type and state prediction reports. Results: Validation across multiple public datasets demonstrated that scSelector effectively resolves functional heterogeneity within broader cell types, such as identifying distinct alpha-cell subpopulations with unique remodeling capabilities in pancreatic tissue. It successfully characterized rare populations, including platelets in PBMCs and extremely low-abundance endothelial cells in liver tissue (as few as 53 cells). Additionally, scSelector revealed that cells discarded by standard QC can represent biologically functional subpopulations, and it accurately dissected the states of outlier cells, such as proliferative NK cells. Conclusions: scSelector provides a flexible, researcher-centric platform that moves beyond the constraints of automated pipelines. By combining interactive selection with AI-assisted interpretation, it enhances the precision of scRNA-seq analysis and facilitates the discovery of novel cell types and complex cellular behaviors. Full article
(This article belongs to the Section Bioinformatics)
Show Figures

Figure 1

22 pages, 2261 KB  
Article
Statistical and Multivariate Analysis of the IoT-23 Dataset: A Comprehensive Approach to Network Traffic Pattern Discovery
by Humera Ghani, Shahram Salekzamankhani and Bal Virdee
J. Cybersecur. Priv. 2025, 5(4), 112; https://doi.org/10.3390/jcp5040112 - 16 Dec 2025
Viewed by 875
Abstract
The rapid expansion of Internet of Things (IoT) technologies has introduced significant challenges in understanding the complexity and structure of network traffic data, which is essential for developing effective cybersecurity solutions. This research presents a comprehensive statistical and multivariate analysis of the IoT-23 [...] Read more.
The rapid expansion of Internet of Things (IoT) technologies has introduced significant challenges in understanding the complexity and structure of network traffic data, which is essential for developing effective cybersecurity solutions. This research presents a comprehensive statistical and multivariate analysis of the IoT-23 dataset to identify meaningful network traffic patterns and assess the effectiveness of various analytical methods for IoT security research. The study applies descriptive statistics, inferential analysis, and multivariate techniques, including Principal Component Analysis (PCA), DBSCAN clustering, and factor analysis (FA), to the publicly available IoT-23 dataset. Descriptive analysis reveals clear evidence of non-normal distributions: for example, the features src_bytes, dst_bytes, and src_pkts have skewness values of −4.21, −3.87, and −2.98, and kurtosis values of 38.45, 29.67, and 18.23, respectively. These values indicate highly skewed, heavy-tailed distributions with frequent outliers. Correlation analysis revealed a strong positive correlation (0.97) between orig_bytes and resp_bytes, and a strong negative correlation (−0.76) between duration and resp_bytes, while inferential statistics indicate that linear regression provides optimal modeling of data relationships. Key findings show that PCA is highly effective, capturing 99% of the dataset’s variance and enabling significant dimensionality reduction. DBSCAN clustering identifies six distinct clusters, highlighting diverse network traffic behaviors within IoT environments. In contrast, FA explains only 11.63% of the variance, indicating limited suitability for this dataset. These results establish important benchmarks for future IoT cybersecurity research and demonstrate the superior effectiveness of PCA and DBSCAN for analyzing complex IoT network traffic data. The findings offer practical guidance for researchers in selecting appropriate statistical methods for IoT dataset analysis, ultimately supporting the development of more robust cybersecurity solutions. Full article
(This article belongs to the Special Issue Intrusion/Malware Detection and Prevention in Networks—2nd Edition)
Show Figures

Figure 1

19 pages, 428 KB  
Article
Vocational Education and Training in the European Union: A Data-Driven Comparative Analysis
by Alicia Vila, Laura Calvet, Josep Prieto and Angel A. Juan
Information 2025, 16(12), 1037; https://doi.org/10.3390/info16121037 - 27 Nov 2025
Viewed by 1390
Abstract
Vocational education and training (VET) is a strategic driver of national education and skills development systems. It covers both Initial VET (IVET), which provides young people with vocational qualifications before they enter the labor market, and Continuing VET (CVET), which supports adults in [...] Read more.
Vocational education and training (VET) is a strategic driver of national education and skills development systems. It covers both Initial VET (IVET), which provides young people with vocational qualifications before they enter the labor market, and Continuing VET (CVET), which supports adults in updating or expanding their skills throughout their working lives. VET provides individuals with essential skills for employment and supports economies in adapting to technological, labor market, and social changes. Within the European Union (EU), VET plays a central role in addressing labor market transformation, the green and digital transitions, the rise of artificial intelligence, and the pursuit of social equity. This paper presents a data-driven analysis of VET in the EU countries. It reviews the relevant literature and outlines the role of Cedefop, the European Centre for the Development of Vocational Training, together with its main VET performance indicators. The analysis draws on publicly available Cedefop data on key VET indicators, filtered for reliability and systematically processed to ensure robust results. This research focuses on a selected set of key indicators covering participation in IVET at upper- and post-secondary levels, adult participation in both formal and non-formal learning, government and enterprise expenditure on training, the gender employment gap, and adult employment rates. These indicators are derived from Cedefop data spanning the period 2010–2024, with coverage varying across indicators. This study applies descriptive analysis to identify outlier countries, correlation analysis to explore relationships between indicators, and cluster analysis to group countries with similar VET profiles. It also compares the largest EU countries using common indicators. The results suggest key patterns, differences, and connections in VET performance across EU countries, offering insights for policy development and future research in VET. Full article
Show Figures

Graphical abstract

67 pages, 14448 KB  
Article
Driving Sustainable Development from Fossil to Renewable: A Space–Time Analysis of Electricity Generation Across the EU-28
by Adriana Grigorescu, Cristina Lincaru and Camelia Speranta Pirciog
Sustainability 2025, 17(23), 10620; https://doi.org/10.3390/su172310620 - 26 Nov 2025
Cited by 1 | Viewed by 575
Abstract
The transition to renewable energy is crucial in order to attain sustainable development, lower greenhouse gas emissions, and secure long-term energy security. This study examines spatial–temporal trends in electricity generation (both renewable and non-renewable) across EU-28 countries using monthly Eurostat data (2008–2025) at [...] Read more.
The transition to renewable energy is crucial in order to attain sustainable development, lower greenhouse gas emissions, and secure long-term energy security. This study examines spatial–temporal trends in electricity generation (both renewable and non-renewable) across EU-28 countries using monthly Eurostat data (2008–2025) at the NUTS0 level. Two harmonized Space–Time Cubes (STCs) were constructed for renewable and non-renewable electricity covering the fully comparable 2017–2024 interval, while 2008–2016 data were used for descriptive validation, and 2025 data were used for one-step-ahead forecasting. In this paper, the authors present a novel multi-method approach to energy transition dynamics in Europe, integrating forecasting (ESF), hot-spot detection (EHSA), and clustering (TSC) with the help of a new spatial–temporal modeling framework. The methodology is a step forward in the development of methodological literature, since it regards predictive and exploratory GIS analytics as comparative energy transition evaluation. The paper uses Exponential Smoothing Forecast (ESF) and Emerging Hot Spot Analysis (EHSA) in a GIS-based analysis to uncover the dynamics in the region and the possible production pattern. The ESF also reported strong predictive performance in the form of the mean Root Mean Square Errors (RMSE) of renewable and non-renewable electricity generation of 422.5 GWh and 438.8 GWh, respectively. Of the EU-28 countries, seasonality was statistically significant in 78.6 per cent of locations that relied on hydropower, and 35.7 per cent of locations exhibited structural outliers associated with energy-transition asymmetries. EHSA identified short-lived localized spikes in renewable electricity production in a few Western and Northern European countries: Portugal, Spain, France, Denmark, and Sweden, termed as sporadic renewable hot spots. There were no cases of persistent or increase-based hot spots in any country; therefore, renewable growth is temporally and spatially inhomogeneous in the EU-28. In the case of non-renewable sources, a hot spot was evident in France, with an intermittent hot spot in Spain and sporadic increases over time, but otherwise, there was no statistically significant activity of hot or cold spots in the rest of Europe, indicating structural stagnation in the generation of fossil-based electricity. Time Series Clustering (TSC) determined 10 temporal clusters in the generation of renewable and non-renewable electricity. All renewable clusters were statistically significantly increasing (p < 0.001), with the most substantial increase in Cluster 4 (statistic = 9.95), observed in Poland, Finland, Portugal, and the Netherlands, indicating a transregional phase acceleration of renewable electricity production in northern, western, and eastern Europe. Conversely, all non-renewable clusters showed declining trends (p < 0.001), with Cluster 5 (statistic = −8.58) showing a concerted reduction in the use of fossil-based electricity, in line with EU decarbonization policies. The results contribute to an improved understanding of the spatial dynamics of the European energy transition and its potential to support energy security, reduce fossil fuel dependency, and foster balanced regional development. These insights are crucial to harmonize policy measures with the objectives of the European Green Deal and the United Nations Sustainable Development Goals (especially Goals 7, 11, and 13). Full article
Show Figures

Figure 1

9 pages, 771 KB  
Proceeding Paper
User-Specific Load Profile Clustering for Automotive Battery Applications
by Jozsef Gabor Pazmany, Zoltan Szeli and Krisztian Enisz
Eng. Proc. 2025, 113(1), 74; https://doi.org/10.3390/engproc2025113074 - 19 Nov 2025
Viewed by 354
Abstract
In applied battery research, use-case-driven prediction is becoming increasingly important, particularly for predicting real-life load profiles. This study proposes techniques to forecast lifetime load profiles for traction batteries, comparing urban- and highway-dominated vehicular use cases. Both charging and discharging scenarios are analyzed. We [...] Read more.
In applied battery research, use-case-driven prediction is becoming increasingly important, particularly for predicting real-life load profiles. This study proposes techniques to forecast lifetime load profiles for traction batteries, comparing urban- and highway-dominated vehicular use cases. Both charging and discharging scenarios are analyzed. We examine the uncertainty in these profiles and conduct a sensitivity analysis to understand the relationship between load profiles and user behavior. In this study, we introduce a novel methodology that maps behavioral and environmental parameters to battery load clusters, enabling us to identify high-risk aging scenarios. Based on parameter studies, we perform load profile clustering to identify critical use case groups and observe key parameter interactions. We present a case study of an idealized driver under Hungarian environmental conditions to predict outlier battery usage in fleets. This novel approach enables more robust predictions of aging and performance degradation for automotive traction batteries across different user clusters. Full article
(This article belongs to the Proceedings of The Sustainable Mobility and Transportation Symposium 2025)
Show Figures

Figure 1

13 pages, 2835 KB  
Article
Sugarcane Genetic Diversity Study of Germplasm Bank and Assessment of a Core Collection
by Maria Francisca Perera, Andrea Natalia Peña Malavera, Diego Daniel Henriquez, Aldo Sergio Noguera, Josefina Racedo and Santiago Ostengo
Agronomy 2025, 15(11), 2638; https://doi.org/10.3390/agronomy15112638 - 18 Nov 2025
Viewed by 531
Abstract
Understanding the genetic diversity and population structure of sugarcane germplasm banks is essential for generating progenies with maximum variability. In this study, 350 accessions from the EEAOC germplasm bank were genotyped using DArT-seq markers. Genetic diversity, population structure, and variability were assessed through [...] Read more.
Understanding the genetic diversity and population structure of sugarcane germplasm banks is essential for generating progenies with maximum variability. In this study, 350 accessions from the EEAOC germplasm bank were genotyped using DArT-seq markers. Genetic diversity, population structure, and variability were assessed through Bayesian analysis, principal coordinate analysis (PCoA), and analysis of molecular variance (AMOVA). Additionally, different sizes of core collections were evaluated. After filtering, 74,969 high-quality SNPs were retained, and two outlier genotypes were excluded. The mean observed heterozygosity (HO) was 0.28, while the mean expected heterozygosity (HE) was 0.3. Polymorphic information content (PIC) values ranged from 0 to 0.38 (mean 0.22), and the mean discrimination power (Dj) was 0.28. Structure and PCoA analyses consistently revealed three genetic clusters. AMOVA indicated that most of the genetic variation was found within subpopulations, while 10.25% was attributable to differences among them (p < 0.0001), where ΦFST suggested moderate genetic differentiation. Core collection analysis showed that a subset of 35 genotypes (10%) captured nearly 96% of the total genetic diversity, while a 30% core captured over 98%. These results provide valuable information for the effective management and utilization of sugarcane genetic resources and support the design of breeding strategies to develop superior cultivars. Full article
(This article belongs to the Section Crop Breeding and Genetics)
Show Figures

Figure 1

19 pages, 2796 KB  
Article
Real-Time Physiological Activity and Sleep State Monitoring System Using TS2Vec Embeddings and DBSCAN Clustering for Heart Rate and Motor Response Analysis in IoMT
by Arifin Arifin, Harmiati Harbi, Andi Silvia Indriani, Ida Laila, Bualkar Abdullah, Alridho, Irfan Idris and Jalu Ahmad Prakosa
Signals 2025, 6(4), 67; https://doi.org/10.3390/signals6040067 - 17 Nov 2025
Viewed by 1053
Abstract
Monitoring physiological activity and sleep states in real time is challenging, particularly for continuous assessment in daily life settings using wearable IoMT devices. We developed a 24 h wearable system that integrates electrocardiogram (ECG) electrodes for heart rate measurement and a glove-mounted flex [...] Read more.
Monitoring physiological activity and sleep states in real time is challenging, particularly for continuous assessment in daily life settings using wearable IoMT devices. We developed a 24 h wearable system that integrates electrocardiogram (ECG) electrodes for heart rate measurement and a glove-mounted flex sensor for motor responses, connected through an Internet of Medical Things (IoMT) platform. Flex signals were combined using principal component analysis (PCA) to generate a single kinematic channel, then standardized with heart rate. Time-series windows were embedded using TS2Vec and clustered with DBSCAN, while t-SNE was applied only for visualization. The framework identified four physiologically coherent states: (i) nocturnal sleep with the lowest heart rate and minimal motion, (ii) evening pre-sleep with low movement and moderately higher heart rate, (iii) daytime activity with variable motion and mid-range heart rate, and (iv) late-day high-intensity activity with the highest heart rate and increased motor responses. A few outliers were observed during transient body movements or sensor readjustments, which were identified and excluded during preprocessing to ensure stable clustering results. Across 24 h, heart rate ranged from 52 to 96 bpm (mean 77.4), while flexion spanned 0 to 165° (mean 52.5°), showing alignment between movement intensity and cardiac response. This integrated sensing and analytics pipeline provides an interpretable, subject-specific state map that enables continuous remote monitoring of physiological activity and sleep patterns. Full article
Show Figures

Figure 1

21 pages, 2623 KB  
Article
A Cluster-Based Filtering Approach to SCADA Data Preprocessing for Wind Turbine Condition Monitoring and Fault Detection
by Krzysztof Kijanowski, Tomasz Barszcz and Phong Ba Dao
Energies 2025, 18(22), 5954; https://doi.org/10.3390/en18225954 - 12 Nov 2025
Viewed by 677
Abstract
The high cost of wind turbine maintenance has intensified the need for reliable fault detection and condition monitoring methods. While Supervisory Control and Data Acquisition (SCADA) systems provide valuable operational data, the raw signals often contain noise, outliers, and missing or redundant entries, [...] Read more.
The high cost of wind turbine maintenance has intensified the need for reliable fault detection and condition monitoring methods. While Supervisory Control and Data Acquisition (SCADA) systems provide valuable operational data, the raw signals often contain noise, outliers, and missing or redundant entries, which can compromise analysis accuracy. This study presents a novel cluster-based outlier removal approach for SCADA data preprocessing, featuring a unique flexibility to include or exclude negative power values—a factor rarely investigated but potentially critical for fault detection performance. The method applies the K-Means++ unsupervised clustering algorithm to group data points along the wind speed–power curve. The number of clusters is determined heuristically using the elbow method, while outliers are identified through Mahalanobis distance with thresholds derived from Chebyshev’s inequality theorem. The approach was validated using SCADA data from a wind farm in Portugal and further assessed with a CUSUM test-based structural change detection method to study how preprocessing choices—outlier thresholds (5% vs. 1%) and inclusion/exclusion of negative power values—affect early fault identification. Results demonstrate reliable fault detection up to 14 days before failure, retaining over 99% of the original dataset. This work provides key insights into preprocessing impacts on model reliability and offers an open-source Python implementation for reproducibility. Full article
(This article belongs to the Special Issue Machine Learning in Renewable Energy Resource Assessment)
Show Figures

Figure 1

25 pages, 5830 KB  
Article
Research on Arch Dam Deformation Safety Early Warning Method Based on Effect Separation of Regional Environmental Variables and Knowledge-Driven Approach
by Jianxue Wang, Fei Tong, Zhiwei Gao, Lin Cheng and Shuaiyin Zhao
Water 2025, 17(22), 3217; https://doi.org/10.3390/w17223217 - 11 Nov 2025
Viewed by 617
Abstract
There are significant differences in the deformation patterns of different parts of arch dams, and there is a common situation of periodic data loss. To accurately analyze the deformation behavior of arch dams, this paper proposes a safety warning and anomaly diagnosis method [...] Read more.
There are significant differences in the deformation patterns of different parts of arch dams, and there is a common situation of periodic data loss. To accurately analyze the deformation behavior of arch dams, this paper proposes a safety warning and anomaly diagnosis method for arch dam deformation based on the separation of environmental variable effects in different partitions and a knowledge-driven approach. This method combines various techniques such as an optimized ISODATA clustering method, probabilistic principal component analysis (PPCA), square prediction error (SPE) norm control chart, and contribution chart. By defining data forms and rules, existing engineering specifications and experience are transformed into “knowledge” and applied to the operation and management of arch dams, achieving accurate monitoring of arch dam deformation status and timely diagnosis of outliers. Through monitoring data verification of horizontal displacement in a certain arch dam partition, the results show that this method can accurately identify deformation anomalies in the arch dam and effectively separate the influence of environmental variables and noise interference, providing strong support for the safe operation of the arch dam. Accurate deformation monitoring of arch dams is essential for ensuring structural safety and optimizing operational management. However, conventional early warning indicators and empirical models often fail to capture the spatial heterogeneity of deformation and the complex coupling between environmental variables and structural responses. To overcome these limitations, this study proposes a knowledge-driven safety early warning and anomaly diagnosis model for arch dam deformation, based on spatiotemporal clustering and partitioned environmental variable separation. The method integrates the optimized ISODATA clustering algorithm, probabilistic principal component analysis (PPCA), squared prediction error (SPE) control chart, and contribution chart to establish a comprehensive monitoring framework. The optimized ISODATA identifies deformation zones with similar mechanical behavior, PPCA separates environmental influences such as temperature and reservoir level from structural responses, and the SPE and contribution charts quantify abnormal variations and locate potential risk regions. Application of the proposed method to long-term deformation monitoring data demonstrates that the PPCA-based framework effectively separates environmental effects, improves the interpretability of zoned deformation characteristics, and enhances the accuracy and reliability of anomaly identification compared with conventional approaches. These findings indicate that the proposed knowledge-driven model provides a robust and interpretable framework for precise deformation safety evaluation of arch dams. Full article
Show Figures

Figure 1

14 pages, 11890 KB  
Article
Spatiotemporal Analysis of Skier Versus Snowboarder Injury Patterns: A GIS-Based Comparative Study at a Large West Coast Resort
by Matt Bisenius and Ming-Chih Hung
ISPRS Int. J. Geo-Inf. 2025, 14(11), 442; https://doi.org/10.3390/ijgi14110442 - 8 Nov 2025
Viewed by 1276
Abstract
GPS tracking has made ski injury data abundant, yet few studies have mapped where incidents actually occur or how those patterns differ between skiers and snowboarders. To address this gap, we analyzed 8719 GPS-located incidents (4196 skier; 4523 snowboarder) spanning four seasons (2017–2022, [...] Read more.
GPS tracking has made ski injury data abundant, yet few studies have mapped where incidents actually occur or how those patterns differ between skiers and snowboarders. To address this gap, we analyzed 8719 GPS-located incidents (4196 skier; 4523 snowboarder) spanning four seasons (2017–2022, excluding 2019–2020 due to COVID-19) at a large West Coast resort in California. Incidents were aggregated into 45 m hexagons and analyzed using Getis–Ord Gi* hot spot analysis, Local Outlier Analysis (LOA), and a space–time cube with time-series clustering. Hot spot analysis identified both activity-specific and overlapping high-injury concentrations at the 99% confidence level (p < 0.01). The LOA revealed no spatial overlap between skier and snowboarder High-High classifications (areas with high incident counts surrounded by other high-count areas) at the 95% confidence level. Temporal analysis exposed distinct patterns by activity: Time Series Clustering revealed skier incidents concentrated at holiday-sensitive locations versus stable zones, while snowboarder incidents separated into sustained high-activity versus baseline areas. These findings indicate universal safety strategies may be insufficient; targeted, activity-specific interventions may warrant investigation. The methodology provides a reproducible framework for spatial injury surveillance applicable across the ski industry. Full article
Show Figures

Figure 1

28 pages, 4910 KB  
Article
Monitoring the Integrity and Vulnerability of Linear Urban Infrastructure in a Reclaimed Coastal City Using SAR Interferometry
by WoonSeong Jeong, Moon-Soo Song, Manik Das Adhikari and Sang-Guk Yum
Buildings 2025, 15(21), 3865; https://doi.org/10.3390/buildings15213865 - 26 Oct 2025
Cited by 2 | Viewed by 1141
Abstract
Reclaimed coastal areas are highly susceptible to uneven subsidence caused by the consolidation of soft marine deposits, which can induce differential settlement, structural deterioration, and systemic risks to urban infrastructure. Further, engineering activities, such as construction and loadings, exacerbate subsidence, impacting infrastructure stability. [...] Read more.
Reclaimed coastal areas are highly susceptible to uneven subsidence caused by the consolidation of soft marine deposits, which can induce differential settlement, structural deterioration, and systemic risks to urban infrastructure. Further, engineering activities, such as construction and loadings, exacerbate subsidence, impacting infrastructure stability. Therefore, monitoring the integrity and vulnerability of linear urban infrastructure after construction on reclaimed land is critical for understanding settlement dynamics, ensuring safe and reliable operation and minimizing cascading hazards. Subsequently, in the present study, to monitor deformation of the linear infrastructure constructed over decades-old reclaimed land in Mokpo city, South Korea (where 70% of urban and port infrastructure is built on reclaimed land), we analyzed 79 Sentinel-1A SLC ascending-orbit datasets (2017–2023) using the Persistent Scatterer Interferometry (PSInSAR) technique to quantify vertical land motion (VLM). Results reveal settlement rates ranging from −12.36 to 4.44 mm/year, with an average of −1.50 mm/year across 1869 persistent scatterers located along major roads and railways. To interpret the underlying causes of this deformation, Casagrande plasticity analysis of subsurface materials revealed that deep marine clays beneath the reclaimed zones have low permeability and high compressibility, leading to slow pore-pressure dissipation and prolonged consolidation under sustained loading. This geotechnical behavior accounts for the persistent and spatially variable subsidence observed through PSInSAR. Spatial pattern analysis using Anselin Local Moran’s I further identified statistically significant clusters and outliers of VLM, delineating critical infrastructure segments where concentrated settlement poses heightened risks to transportation stability. A hyperbolic settlement model was also applied to anticipate nonlinear consolidation trends at vulnerable sites, predicting persistent subsidence through 2030. Proxy-based validation, integrating long-term groundwater variations, lithostratigraphy, effective shear-wave velocity (Vs30), and geomorphological conditions, exhibited the reliability of the InSAR-derived deformation fields. The findings highlight that Mokpo’s decades-old reclamation fills remain geotechnically unstable, highlighting the urgent need for proactive monitoring, targeted soil improvement, structural reinforcement, and integrated InSAR-GNSS monitoring frameworks to ensure the structural integrity of road and railway infrastructure and to support sustainable urban development in reclaimed coastal cities worldwide. Full article
Show Figures

Figure 1

16 pages, 2438 KB  
Article
Data-Driven Noise-Resilient Method for Wind Farm Reactive Power Optimization
by Zhen Pan, Lijuan Huang, Kaiwen Huang, Guan Bai and Lin Zhou
Processes 2025, 13(10), 3303; https://doi.org/10.3390/pr13103303 - 15 Oct 2025
Viewed by 504
Abstract
Accurate reactive power optimization in wind farms (WFs) is critical for optimizing operations and ensuring grid stability, yet it faces challenges from noisy, nonlinear, and dynamic Supervisory Control and Data Acquisition (SCADA) data. This study proposes an innovative framework, WBS-BiGRU, integrating three novel [...] Read more.
Accurate reactive power optimization in wind farms (WFs) is critical for optimizing operations and ensuring grid stability, yet it faces challenges from noisy, nonlinear, and dynamic Supervisory Control and Data Acquisition (SCADA) data. This study proposes an innovative framework, WBS-BiGRU, integrating three novel components to address these issues. Firstly, the Wavelet-DBSCAN (WDBSCAN) method combines wavelet transform’s time–frequency analysis with density-based spatial clustering of applications with noise (DBSCAN)’s density-based clustering to effectively remove noise and outliers from complex WF datasets, leveraging multi-scale features for enhanced adaptability to non-stationary signals. Subsequently, a Boomerang Evolutionary Optimization (BAEO) with the Seasonal Decomposition Improved Process (SDIP) synergistically decomposes time series into trend, seasonal, and residual components, generating diverse candidate solutions to optimize data inputs. Finally, a Bidirectional Gated Recurrent Unit (BiGRU) network enhanced with an attention mechanism captures long-term dependencies in temporal data and dynamically focuses on key features, improving reactive power forecasting precision. The WBS-BiGRU framework significantly enhances forecasting accuracy and robustness, offering a reliable solution for WF operation optimization and equipment health management. Full article
Show Figures

Figure 1

Back to TopTop