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Search Results (156)

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Keywords = nonlinear site response

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30 pages, 3923 KiB  
Article
Exploring the Key Factors Influencing the Plays’ Continuous Intention of Ancient Architectural Cultural Heritage Serious Games: An SEM–ANN–NCA Approach
by Qian Bao, Siqin Wang, Ken Nah and Wei Guo
Buildings 2025, 15(15), 2648; https://doi.org/10.3390/buildings15152648 - 27 Jul 2025
Viewed by 294
Abstract
Serious games (SGs) have been widely employed in the digital preservation and transmission of architectural heritage. However, the key determinants and underlying mechanisms driving users’ continuance intentions toward ancient-architecture cultural heritage serious games (CH-SGs) have not been thoroughly investigated. Accordingly, a conceptual model [...] Read more.
Serious games (SGs) have been widely employed in the digital preservation and transmission of architectural heritage. However, the key determinants and underlying mechanisms driving users’ continuance intentions toward ancient-architecture cultural heritage serious games (CH-SGs) have not been thoroughly investigated. Accordingly, a conceptual model grounded in the stimulus–organism–response (S–O–R) framework was developed to elucidate the affective and behavioral effects experienced by CH-SG users. Partial least squares structural equation modeling (PLS-SEM) and artificial neural networks (ANNs) were employed to capture both the linear and nonlinear relationships among model constructs. By integrating sufficiency logic (PLS-SEM) and necessity logic (necessary condition analysis, NCA), “must-have” and “should-have” factors were identified. Empirical results indicate that cultural authenticity, knowledge acquisition, perceived enjoyment, and design aesthetics each exert a positive influence—of varying magnitude—on perceived value, cultural identification, and perceived pleasure, thereby shaping users’ continuance intentions. Moreover, cultural authenticity and perceived enjoyment were found to be necessary and sufficient conditions, respectively, for enhancing perceived pleasure and perceived value, which in turn indirectly bolster CH-SG users’ sustained use intentions. By creating an immersive, narratively rich, and engaging cognitive experience, CH-SGs set against ancient architectural backdrops not only stimulate users’ willingness to visit and protect heritage sites but also provide designers and developers with critical insights for optimizing future CH-SG design, development, and dissemination. Full article
(This article belongs to the Section Architectural Design, Urban Science, and Real Estate)
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21 pages, 13986 KiB  
Article
Seismic Response Analysis of Nuclear Island Structures Considering Complex Soil–Pile–Structure Dynamic Interaction
by Xunqiang Yin, Junkai Zhang, Min Zhao and Weilong Yang
Buildings 2025, 15(15), 2620; https://doi.org/10.3390/buildings15152620 - 24 Jul 2025
Viewed by 290
Abstract
Seismic responses of Nuclear Island (NI) structures have great significance in the foundation adaptability analysis and the seismic design of equipment. However, with the increasing complexity of nuclear power site conditions, establishing a reasonable and effective soil–pile–structure dynamic interaction model has become the [...] Read more.
Seismic responses of Nuclear Island (NI) structures have great significance in the foundation adaptability analysis and the seismic design of equipment. However, with the increasing complexity of nuclear power site conditions, establishing a reasonable and effective soil–pile–structure dynamic interaction model has become the key technical problem that needs to be solved. In this study, a pseudo three-dimensional soil–pile–structure dynamic interaction model considering soil nonlinearity and heterogeneity is developed for seismic response analysis of NI structures. Specifically, the nonlinearity of the near-field soil is described via the equivalent linear method, the radiation damping effect of half space is simulated through viscous boundary, and the displacement/stress conditions at lateral boundaries of the heterogeneous site are derived from free-field response analysis. Meanwhile, an equivalent stiffness–mass principle is established to simplify NI superstructures, while pile group effects are incorporated via a node-coupling scheme within the finite-element framework. Two validation examples are presented to demonstrate the accuracy and efficiency of the proposed model. Finally, seismic response analysis of two typical NI structure of reactor types (CPR1000 and AP1000) based on the actual complex site conditions in China is also presented to study the effect of radiation damping, soil conditions, and pile foundation. Key findings demonstrate the necessity of integrating SSI effects and nonlinear characteristics of non-rock foundations. While the rock-socketed pile exhibits superior performance compared to the CFG pile alternative; this advantage is offset by higher costs and construction complexity. The research findings can serve as a valuable reference for the foundation adaptability analysis and optimizing the design of equipment under the similar complex condition of the soil site. Full article
(This article belongs to the Special Issue Dynamic Response of Civil Engineering Structures under Seismic Loads)
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17 pages, 3127 KiB  
Article
The Impact of Pile Diameter on the Performance of Single Piles: A Kinematic Analysis Based on the TBEC 2018 Guidelines
by Mehmet Hayrullah Akyıldız, Mehmet Salih Keskin, Senem Yılmaz Çetin, Sabahattin Kaplan and Gültekin Aktaş
Buildings 2025, 15(14), 2540; https://doi.org/10.3390/buildings15142540 - 19 Jul 2025
Viewed by 236
Abstract
This study investigates the effect of pile diameter on the seismic performance of single piles using the kinematic interaction framework outlined in Method III of the Turkish Building Earthquake Code TBEC-2018. Pile diameters of 65 cm, 80 cm, and 100 cm were analyzed [...] Read more.
This study investigates the effect of pile diameter on the seismic performance of single piles using the kinematic interaction framework outlined in Method III of the Turkish Building Earthquake Code TBEC-2018. Pile diameters of 65 cm, 80 cm, and 100 cm were analyzed under four different soil profiles—soft clay, stiff clay, very loose sand-A, and very loose sand-B. The methodology integrated nonlinear spring modeling (P-y, T-z, Q-z) for soil behavior, one-dimensional site response analysis using DEEPSOIL, and structural analysis with SAP2000. The simulation results showed that increasing the pile diameter led to a significant rise in internal forces: the maximum bending moment increased up to 4.0 times, and the maximum shear force increased 4.5 times from the smallest to the largest pile diameter. Horizontal displacements remained nearly constant, whereas vertical displacements decreased by almost 50%, indicating improved pile–soil stiffness interaction. The depth of the maximum moment shifted according to the soil stiffness, and stress concentrations were observed at the interfaces of stratified layers. The findings underline the importance of considering pile geometry and soil layering in seismic design. This study provides quantitative insights into the trade-off between displacement control and force demand in seismic pile design, contributing to safer foundation strategies in earthquake-prone regions. Full article
(This article belongs to the Section Building Structures)
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17 pages, 278 KiB  
Essay
Educational Leadership: Enabling Positive Planetary Action Through Regenerative Practices and Complexity Leadership Theory
by Marie Beresford-Dey
Challenges 2025, 16(3), 32; https://doi.org/10.3390/challe16030032 - 15 Jul 2025
Viewed by 396
Abstract
Uniquely rooted in regenerative leadership and complemented by Complexity Leadership Theory (CLT), this conceptual essay offers a theoretical exploration of how educational institutions can act as dynamic systems that catalyze adaptive, community-led responses to anthropocentric socio-environmental crises. Rather than sustaining existing structures, educational [...] Read more.
Uniquely rooted in regenerative leadership and complemented by Complexity Leadership Theory (CLT), this conceptual essay offers a theoretical exploration of how educational institutions can act as dynamic systems that catalyze adaptive, community-led responses to anthropocentric socio-environmental crises. Rather than sustaining existing structures, educational leadership for regeneration seeks to restore ecological balance and nurture emergent capacities for long-term resilience. Positioned as key sites of influence, educational institutions are explored as engines of innovation capable of mobilizing students, educators, and communities toward collective environmental action. CLT offers a valuable lens for understanding how leadership emerges from nonlinear, adaptive processes within schools, enabling the development of innovative, collaborative, and responsive strategies required for navigating complexity and leading planetary-positive change. Drawing on a synthesis of the recent global literature, this paper begins by outlining the need to go beyond sustainability in envisioning regenerative futures, followed by an introduction to regenerative principles. It then examines the current and evolving role of educational leadership, the relevance in enabling whole-institution transformation, and how this relates to regenerative practices. The theoretical frameworks of systems thinking and CLT are introduced before noting their application within regenerative educational leadership. The final sections identify implementation challenges and offer practical recommendations, including curriculum innovation, professional development, and youth-led advocacy, before concluding with a call for education as a vehicle for cultivating planetary-conscious citizens and systemic change. This work contributes a timely and theoretically grounded model for reimagining educational leadership in an era of global turbulence. Full article
(This article belongs to the Section Planetary Health Education and Communication)
21 pages, 10296 KiB  
Article
Spatiotemporal Mechanical Effects of Framework–Slope Systems Under Frost Heave Conditions
by Wendong Li, Xiaoqiang Hou, Jixian Ren and Chaoyang Wu
Appl. Sci. 2025, 15(14), 7877; https://doi.org/10.3390/app15147877 - 15 Jul 2025
Viewed by 263
Abstract
To investigate the slope instability caused by differential frost heaving mechanisms from the slope crest to the toe during frost heave processes, this study takes a typical silty clay slope in Xinjiang, China, as the research object. Through indoor triaxial consolidated undrained shear [...] Read more.
To investigate the slope instability caused by differential frost heaving mechanisms from the slope crest to the toe during frost heave processes, this study takes a typical silty clay slope in Xinjiang, China, as the research object. Through indoor triaxial consolidated undrained shear tests, eight sets of natural and frost-heaved specimens were prepared under confining pressure conditions ranging from 100 to 400 kPa. The geotechnical parameters of the soil in both natural and frost-heaved states were obtained, and a spatiotemporal thermo-hydro-mechanical coupled numerical model was established to reveal the dynamic evolution law of anchor rod axial forces and the frost heave response mechanism between the frame and slope soil. The analytical results indicate that (1) the frost heave process is influenced by slope boundaries, resulting in distinct spatial variations in the temperature field response across the slope surface—namely pronounced responses at the crest and toe but a weaker response in the mid-slope. (2) Under the coupled drive of the water potential gradient and gravitational potential gradient, the ice content in the toe area increases significantly, and the horizontal frost heave force exhibits exponential growth, reaching its peak value of 92 kPa at the toe in February. (3) During soil freezing, the reverse stress field generated by soil arching shows consistent temporal variation trends with the temperature field. Along the height of the soil arch, the intensity of the reverse frost heave force field displays a nonlinear distribution characteristic of initial strengthening followed by attenuation. (4) By analyzing the changes in anchor rod axial forces during frost heaving, it was found that axial forces during the frost heave period are approximately 1.3 times those under natural conditions, confirming the frost heave period as the most critical condition for frame anchor design. Furthermore, through comparative analysis with 12 months of on-site anchor rod axial force monitoring data, the reliability and accuracy of the numerical simulation model were validated. These research outcomes provide a theoretical basis for the design of frame anchor support systems in seasonally frozen regions. Full article
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19 pages, 4717 KiB  
Article
Seismic Response Characteristics of High-Speed Railway Hub Station Considering Pile-Soil Interactions
by Ning Zhang and Ziwei Chen
Buildings 2025, 15(14), 2466; https://doi.org/10.3390/buildings15142466 - 14 Jul 2025
Viewed by 189
Abstract
As a key transportation infrastructure, it is of great significance to ensure the seismic safety of the high-speed railway hub station. Taking Changde high-speed railway hub station as background, a comprehensive 3D numerical model of the high-speed railway station structure is proposed to [...] Read more.
As a key transportation infrastructure, it is of great significance to ensure the seismic safety of the high-speed railway hub station. Taking Changde high-speed railway hub station as background, a comprehensive 3D numerical model of the high-speed railway station structure is proposed to consider the engineering geological characteristics of the site, soil nonlinearity, and pile-soil interactions. The results show that the hub station structural system, considering pile-soil interaction, presents the ‘soft-upper-rigid-down’ characteristics as a whole, and the natural vibration is lower than that of the station structure with a rigid foundation assumption. Under the action of three strong seismic motions, the nonlinear site seismic effect is significant, the surface acceleration is significantly enlarged, and decreases with the buried depth. The interaction between pile and soil is related to the nonlinear seismic effect of the site, which deforms together to resist the foundation deformation caused by the strong earthquake motions, and the depth range affected by the interaction between the two increases with the increase of the intensity of earthquake motion. Among the three kinds of input earthquake motions, the predominant frequency of the Kobe earthquake is the closest to the natural vibration of the station structure system, followed by the El Centro earthquake. Moreover, the structures above the foundation of the high-speed railway hub station structural system are more sensitive to the spectral characteristics of Taft waves and El Centro waves compared to the site soil. This is also the main innovation point of this study. The existence of the roof leads to the gradual amplification of the seismic response of the station frame structure with height, and the seismic response amplification at the connection between the roof and the frame structure is the largest. The maximum story drift angle at the top floor of the station structure is also greater than that at the bottom floor. Full article
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16 pages, 5423 KiB  
Article
Effect of Nonlinear Constitutive Models on Seismic Site Response of Soft Reclaimed Soil Deposits
by Sadiq Shamsher, Myoung-Soo Won, Young-Chul Park, Yoon-Ho Park and Mohamed A. Sayed
J. Mar. Sci. Eng. 2025, 13(7), 1333; https://doi.org/10.3390/jmse13071333 - 11 Jul 2025
Viewed by 244
Abstract
This study investigates the impact of nonlinear constitutive models on one-dimensional seismic site response analysis (SRA) for soft, reclaimed soil deposits in Saemangeum, South Korea. Two widely used models, MKZ and GQ/H, were applied to three representative soil profiles using the DEEPSOIL program. [...] Read more.
This study investigates the impact of nonlinear constitutive models on one-dimensional seismic site response analysis (SRA) for soft, reclaimed soil deposits in Saemangeum, South Korea. Two widely used models, MKZ and GQ/H, were applied to three representative soil profiles using the DEEPSOIL program. Ground motions were scaled to bedrock peak ground accelerations (PGAs) corresponding to annual return periods (ARPs) of 1000, 2400, and 4800 years. Seismic response metrics include the ratio of GQ/H to MKZ shear strain, effective PGA (EPGA), and short- and long-term amplification factors (Fa and Fv). The results highlight the critical role of the site-to-motion period ratio (Tg/Tm) in controlling seismic behavior. Compared to the MKZ, the GQ/H model, which features strength correction and improved stiffness retention, predicts lower shear strains and higher surface spectral accelerations, particularly under strong shaking and shallow conditions. Model differences are most pronounced at low Tg/Tm values, where MKZ tends to underestimate amplification and overestimate strain due to its limited ability to reflect site-specific shear strength. Relative to code-based amplification factors, the GQ/H model yields lower short-term estimates, reflecting the disparity between stiff inland reference sites and the soft reclaimed conditions at Saemangeum. These findings emphasize the need for strength-calibrated constitutive models to improve the accuracy of site-specific seismic hazard assessments. Full article
(This article belongs to the Section Marine Hazards)
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21 pages, 2655 KiB  
Article
Integrative Modeling of Urinary Metabolomics and Metal Exposure Reveals Systemic Impacts of Electronic Waste in Exposed Populations
by Fiona Hui, Zhiqiang Pang, Charles Viau, Gerd U. Balcke, Julius N. Fobil, Niladri Basu and Jianguo Xia
Metabolites 2025, 15(7), 456; https://doi.org/10.3390/metabo15070456 - 5 Jul 2025
Viewed by 667
Abstract
Background: Informal electronic waste (e-waste) recycling practices release a complex mixture of pollutants, particularly heavy metals, into the environment. Chronic exposure to these contaminants has been linked to a range of health risks, but the molecular underpinnings remain poorly understood. In this [...] Read more.
Background: Informal electronic waste (e-waste) recycling practices release a complex mixture of pollutants, particularly heavy metals, into the environment. Chronic exposure to these contaminants has been linked to a range of health risks, but the molecular underpinnings remain poorly understood. In this study, we investigated the alterations in metabolic profiles due to e-waste exposure and linked these metabolites to systemic biological effects. Methods: We applied untargeted high-resolution metabolomics using dual-column LC-MS/MS and a multi-step analysis workflow combining MS1 feature detection, MS2 annotation, and chemical ontology classification, to characterize urinary metabolic alterations in 91 e-waste workers and 51 community controls associated with the Agbogbloshie site (Accra, Ghana). The impacts of heavy metal exposure in e-waste workers were assessed by establishing linear regression and four-parameter logistic (4PL) models between heavy metal levels and metabolite concentrations. Results: Significant metal-associated metabolomic changes were identified. Both linear and nonlinear models revealed distinct sets of exposure-responsive compounds, highlighting diverse biological responses. Ontology-informed annotation revealed systemic effects on lipid metabolism, oxidative stress pathways, and xenobiotic biotransformation. This study demonstrates how integrating chemical ontology and nonlinear modeling facilitates exposome interpretation in complex environments and provides a scalable template for environmental biomarker discovery. Conclusions: Integrating dose–response modeling and chemical ontology analysis enables robust interpretation of exposomics datasets when direct compound identification is limited. Our findings indicate that e-waste exposure induces systemic metabolic alterations that can underlie health risks and diseases. Full article
(This article belongs to the Special Issue Method Development in Metabolomics and Exposomics)
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19 pages, 6337 KiB  
Article
Responses of Fish Zeta Diversity (ζ) to Human Pressure and Cumulative Effects: A Feasibility Study of Fishing Ban Measures in the Pearl River Basin, China
by Jiayang He, Hao Liu, Xianda Bi and Zhiqiang Wu
Biology 2025, 14(7), 796; https://doi.org/10.3390/biology14070796 - 30 Jun 2025
Viewed by 289
Abstract
Amid declining fish diversity and human pressures in freshwater ecosystems, robust basin-scale assessments are vital for effective fisheries management. This study collated nearly four decades of fishery yields from the Pearl and Yangtze Rivers to identify conservation priorities in the Pearl River Basin. [...] Read more.
Amid declining fish diversity and human pressures in freshwater ecosystems, robust basin-scale assessments are vital for effective fisheries management. This study collated nearly four decades of fishery yields from the Pearl and Yangtze Rivers to identify conservation priorities in the Pearl River Basin. It introduced a novel cumulative effect indicator based on zeta diversity—a biodiversity pattern metric—integrated with cumulative effects analysis for management decision-making. The research employed a multi-site generalized dissimilarity model to examine the non-linear relationships between fish species composition (ζn) and human pressures, environmental factors, and geospatial variations across elevation gradients. The cumulative effect indicator, reflecting responses to anthropogenic stress when assessing ζ2 (related to β diversity), helped evaluate basins for conservation or restoration needs based on their unique or homogenized biotic communities. The results suggest that ζ diversity in low-elevation sub-basins has a stronger filtering effect on ζ by human pressures than in mid- to high-elevation sub-basins, where community aggregation is more random. The impact varied with diversity aspects (nestedness vs. turnover) and zeta order. A negative correlation between cumulative effects and community uniqueness validated the novel cumulative effect indicator’s effectiveness for guiding restoration in the Pearl River Delta, potential fishing bans, and karst conservation. This approach offers a theoretical basis for prioritizing areas for freshwater fish diversity conservation and fishing restrictions in the Pearl River Basin. Full article
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19 pages, 3956 KiB  
Article
Production Prediction Method for Deep Coalbed Fractured Wells Based on Multi-Task Machine Learning Model with Attention Mechanism
by Heng Wen, Jianshu Wu, Ying Zhu, Xuesong Xing, Guangai Wu, Shicheng Zhang, Chengang Xian, Na Li, Cong Xiao, Ying Zhou and Lei Zou
Processes 2025, 13(6), 1787; https://doi.org/10.3390/pr13061787 - 5 Jun 2025
Viewed by 456
Abstract
Deep coalbed methane (CBM) is rich in resources and is an important replacement resource for tight gas in China. Accurate prediction of post-fracture production and dynamic change characteristics of fractured wells of partial CBM is of great significance in predicting the final recovery [...] Read more.
Deep coalbed methane (CBM) is rich in resources and is an important replacement resource for tight gas in China. Accurate prediction of post-fracture production and dynamic change characteristics of fractured wells of partial CBM is of great significance in predicting the final recovery rate. In terms of predicting time-series production, the problem one encounters is low prediction accuracy and poor generalisation ability under limited sample conditions. In this paper, we propose a hybrid deep neural network (AT-GRU-MTL) production prediction model based on the combination of an attention mechanism gated recurrent neural network (GRU) and multi-task learning (MTL), where the AT-GRU is responsible for capturing the nonlinear pattern of the production change, while introducing an MTL method that includes a cross-stitch network (CSN) and a weighted loss using homoskedasticity uncertainty to automatically determine the degree of sharing between multiple tasks and the weighting ratio of the total loss function. The model is applied to several typical deep CBM fracturing wells in China, and the accuracy of gas production prediction reaches 90%, while the accuracy of water production prediction is 68%. The experimental results show that, for the blocks with a very large difference in the order of magnitude of the gas and water production, it is very easy for a certain small order of magnitude to be suppressed from learning during the two-way multi-task learning process, which leads to deterioration of its prediction effect; at the same time, the adaptability of the model is evaluated, and it is found that the model is more advantageous for the wells that have been produced for approximately one year. Meanwhile, the evaluation of the model adaptability shows that the model is more dominant in the prediction of wells with production of about one and a half years. Based on the two test wells with shorter (380 days) and longer (709 days) spans, the results indicate that the model may have insufficient sensitivity to the sudden change of the ratio of gas to water and the failure of the dynamic generalisation of the matrix shrinkage–desorption coupling, and the introduction of physical constraints (such as bottomhole flow pressure, etc.) or the division of the data into the production stages may be attempted to deal with the case subsequently. The research results in this paper provide a theoretical basis for dynamic production prediction and analysis in oil and gas field sites. Full article
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16 pages, 790 KiB  
Article
Fire and Drought Affect Multiple Aspects of Diversity in a Migratory Bird Stopover Community
by Jenna E. Stanek, Chauncey R. Gadek, Sarah E. Milligan, Brent E. Thompson, Keegan A. Tranquillo, Laura L. Trader, Charles D. Hathcock and Stephen M. Fettig
Biology 2025, 14(6), 597; https://doi.org/10.3390/biology14060597 - 24 May 2025
Viewed by 506
Abstract
Drought and high-severity, stand-replacing wildfires can have substantial impacts on the composition of avian communities, including stop-over communities during migration. An inextricable link exists between drought and wildfire, each operating and impacting across different timescales. Many studies have found nonlinear avian abundance trends [...] Read more.
Drought and high-severity, stand-replacing wildfires can have substantial impacts on the composition of avian communities, including stop-over communities during migration. An inextricable link exists between drought and wildfire, each operating and impacting across different timescales. Many studies have found nonlinear avian abundance trends in breeding community time series data that include pre- and post-fire observations, describing an initial decrease in abundance followed by rapid increases that can attenuate over time. Here, we use a fall bird-banding dataset to evaluate shifts in a drought-impacted avian community following wildfire from taxonomic, functional, and phylogenetic perspectives. We looked at the community as a whole and also categorized birds as residents, migrants, and breeders to assess potential varying responses at the study site. We observed post-fire shifts in functional and phylogenetic diversity that corresponded to changes in vegetation. An influx of migratory insectivores post-fire drove much of the variation between pre- and post-fire avian communities and toward a more related, less phylogenetically dispersed community. A concurrent monsoon season drought was also associated with functional and phylogenetic diversity, highlighting the intertwined pulse press effects on avian communities. Overall, our results suggest that, although bird communities are immediately impacted by fire-driven resource changes, they can rebound over time, it is unclear how long-term drought may continue to shape the composition of these avian communities. Full article
(This article belongs to the Special Issue Bird Biology and Conservation)
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16 pages, 525 KiB  
Article
The Impacts of Power Take-Off Surviving Strategies on the Extreme Load Estimations of Wave Energy Converters
by Jian Tan, Yufeng Zhang, Avni Jain and George Lavidas
J. Mar. Sci. Eng. 2025, 13(5), 994; https://doi.org/10.3390/jmse13050994 - 21 May 2025
Viewed by 537
Abstract
The proper design of wave energy converters (WECs) is crucial for ensuring robustness in harsh wave climates without incurring the additional expense of unnecessary overdesign. The power take-off (PTO) mechanism, serving as a vital link between the moving body and the electric generator, [...] Read more.
The proper design of wave energy converters (WECs) is crucial for ensuring robustness in harsh wave climates without incurring the additional expense of unnecessary overdesign. The power take-off (PTO) mechanism, serving as a vital link between the moving body and the electric generator, is a key component in the design load analysis of WECs. However, the setting of PTO system parameters significantly impacts the dynamic behavior of the entire WEC system, leading to alterations in estimated loads. This work is dedicated to studying the influence of PTO control strategies on the identification of extreme loads of a heaving point absorber WEC. A nonlinear time-domain model is established to estimate the dynamic responses and loads of the WEC. Both PTO loads and end-stop loads under extreme conditions are examined, considering the wave climate of a realistic sea site. The results suggest that the PTO setting strategies significantly impact the extreme load exerted on both the PTO system and the end-stop system. Varying the PTO damping within a certain range could lead to a difference of 57% and 63% in short-term extreme loads for the PTO system and the end-stop system, respectively. Furthermore, the impacts of the PTO control strategy appear to be specific to each WEC component. The PTO parameters selected for reducing the extreme PTO loads might increase the extreme end-stop loads. A holistic examination is therefore recommended for estimating the extreme loads of WECs. Full article
(This article belongs to the Section Ocean Engineering)
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20 pages, 1691 KiB  
Article
MEMS-Based Micropacked Thermal Desorption GC/PID for In-Field Volatile Organic Compound Profiling from Hot Mix Asphalt
by Stefano Dugheri, Giovanni Cappelli, Riccardo Gori, Stefano Zampolli, Niccolò Fanfani, Ettore Guerriero, Donato Squillaci, Ilaria Rapi, Lorenzo Venturini, Alexander Pittella, Chiara Vita, Fabio Cioni, Domenico Cipriano, Mieczyslaw Sajewicz, Ivan Elmi, Luca Masini, Simone De Sio, Antonio Baldassarre, Veronica Traversini and Nicola Mucci
Separations 2025, 12(5), 133; https://doi.org/10.3390/separations12050133 - 19 May 2025
Viewed by 2385
Abstract
Background: In response to the growing demand for the real-time, in-field characterization of odorous anthropogenic emissions, this study develops and uses a MEMS-based micropacked thermal desorption Gas Chromatography system coupled with a PhotoIonization Detector (GC/PID) for Hot Mix Asphalt (HMA) plant emissions. Methods: [...] Read more.
Background: In response to the growing demand for the real-time, in-field characterization of odorous anthropogenic emissions, this study develops and uses a MEMS-based micropacked thermal desorption Gas Chromatography system coupled with a PhotoIonization Detector (GC/PID) for Hot Mix Asphalt (HMA) plant emissions. Methods: The innovative portable device, Pyxis GC, enables the high-sensitivity profiling of Volatile Organic Compounds (VOCs), particularly aldehydes and ketones, with sub-ppb detection limits using ambient air as the carrier gas. A comprehensive experimental design optimized the preconcentration parameters, resulting in an efficient, green analytical method evaluated via the Green Analytical Procedure Index (GAPI). Sorbent comparison showed quinoxaline-bridged cavitands outperform the conventional materials. Results and conclusions: The method was successfully deployed on site for source-specific sampling at an HMA plant, generating robust emission fingerprints. To assess environmental impact, a Generalized Additive Model (GAM) was developed, incorporating the process temperature and Sum of Odour Activity Values (SOAV) to predict odour concentrations. The model revealed a significant non-linear influence of temperature on emissions and validated its predictive capability despite the limited sample size. This integrated analytical–statistical approach demonstrates the utility of MEMS technology for real-time air quality assessment and odour dispersion modelling, offering a powerful tool for environmental monitoring and regulatory compliance. Full article
(This article belongs to the Special Issue Separation Techniques on a Miniaturized Scale)
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34 pages, 19699 KiB  
Article
Comprehensive Material Characterization and Seismic Performance Evaluation of a Traditional Masonry Residential Building with Reinforced Concrete Slabs
by Basak Boduroglu Yazici and Oguz Uzdil
Buildings 2025, 15(10), 1710; https://doi.org/10.3390/buildings15101710 - 18 May 2025
Cited by 1 | Viewed by 1023
Abstract
Reinforced concrete began replacing traditional masonry construction in the early 20th century, yet hybrid buildings combining unreinforced masonry (URM) walls with concrete slabs remain prevalent in Istanbul. Understanding their seismic behavior is critical for risk mitigation and heritage preservation. This study investigates a [...] Read more.
Reinforced concrete began replacing traditional masonry construction in the early 20th century, yet hybrid buildings combining unreinforced masonry (URM) walls with concrete slabs remain prevalent in Istanbul. Understanding their seismic behavior is critical for risk mitigation and heritage preservation. This study investigates a seven-story masonry residential building with cast-in-place reinforced concrete slabs constructed in 1953. The assessment involved non-destructive inspections, double flat-jack and shear tests, and geophysical site surveys. A finite element model was developed using Midas Gen software v2020 and analyzed through linear response spectrum and nonlinear pushover analyses based on TBSC-18 and SRMGHS-17. The modulus of elasticity ranged from 200.2 MPa to 1062.2 MPa, and bed joint shear strength varied between 0.50 MPa and 0.79 MPa. The building satisfied inter-story drift criteria for limited damage (SL-3), controlled damage (SL-2), and pre-collapse (SL-1). However, it failed to meet the shear force requirements at all levels. Pushover analysis revealed ultimate lateral capacities of 11,997 kN in the x-direction and 16,209 kN in the y-direction. The findings highlight the shear vulnerability of such hybrid systems and underscore the importance of combining experimental characterization with numerical modeling to develop effective retrofitting strategies. Full article
(This article belongs to the Section Building Structures)
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23 pages, 4072 KiB  
Article
An Explainable Machine Learning Model for Predicting Macroseismic Intensity for Emergency Management
by Federico Mori and Giuseppe Naso
Remote Sens. 2025, 17(10), 1754; https://doi.org/10.3390/rs17101754 - 17 May 2025
Viewed by 424
Abstract
Predicting macroseismic intensity from instrumental ground motion parameters remains a complex task due to the nonlinear relationship with observed damage patterns. An explainable machine learning model based on the XGBoost algorithm was developed to address the challenge. The model is trained on data [...] Read more.
Predicting macroseismic intensity from instrumental ground motion parameters remains a complex task due to the nonlinear relationship with observed damage patterns. An explainable machine learning model based on the XGBoost algorithm was developed to address the challenge. The model is trained on data from Italian earthquakes recorded between 1972 and 2016, linking ground motion recordings to MCS observations located within 3 km. The dataset has been enhanced with site-specific correction factors to better capture local amplification effects. Key input features include Arias Intensity, spectral accelerations at four representative periods (0.15 s, 0.4 s, 0.6 s, and 2 s), and site condition proxies, such as slope and Vs30. The model achieves strong predictive performance (RMSE = 0.73, R2 = 0.76), corresponding to a 33% reduction in residual standard deviation compared to traditional GMICE-based regression methods. To ensure transparency, Shapley Additive Explanations (SHAPs) are used to quantify the contribution of each feature. Arias Intensity emerges as the dominant predictor, followed by spectral ordinates in line with structural response mechanics. As damage severity increases, feature importance shifts from PGA to PGV, while site-specific variables (slope, Vs30) act as refiners rather than amplifiers of shaking. The proposed approach enables near real-time prediction of local damage scenarios and supports data-driven decision-making in seismic emergency management. Full article
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