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Surface and underwater target classification under limited sample sizes based on sound field elevation structure
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作者 Yixin Miao Jin Fu Xue Wang 《Chinese Physics B》 2025年第11期401-414,共14页
Surface/underwater target classification is a key topic in marine information research.However,the complex underwater environment,coupled with the diversity of target types and their variable characteristics,presents ... Surface/underwater target classification is a key topic in marine information research.However,the complex underwater environment,coupled with the diversity of target types and their variable characteristics,presents significant challenges for classifier design.For shallow-water waveguides with a negative thermocline,a residual neural network(ResNet)model based on the sound field elevation structure is constructed.This model demonstrates robust classification performance even when facing low signal-to-noise ratios and environmental mismatches.Meanwhile,to address the reduced generalization ability caused by limited labeled acoustic data,an improved ResNet model based on unsupervised domain adaptation(“proposed UDA-ResNet”)is further constructed.This model incorporates data on simulated elevation structures of the sound field to augment the training process.Adversarial training is employed to extract domain-invariant features from simulated and trial data.These strategies help reduce the negative impact caused by domain differences.Experimental results demonstrate that the proposed method shows strong surface/underwater target classification ability under limited sample sizes,thus confirming its feasibility and effectiveness. 展开更多
关键词 sound field elevation structure surface/underwater target classification limited sample size unsupervised domain adaptation
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Study on adaptive mesh method in the problem of underwater shock waves near water surface
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作者 Fang Wang Xinpeng Yuan Jianzhu An 《Chinese Physics B》 2025年第6期385-399,共15页
This paper focuses on the application of the adaptive mesh method in the study of underwater shock waves near the water surface.By integrating theoretical analysis with a five-equation model under axisymmetric coordin... This paper focuses on the application of the adaptive mesh method in the study of underwater shock waves near the water surface.By integrating theoretical analysis with a five-equation model under axisymmetric coordinates,we developed an optimized computational framework for multi-material fluid simulations.The moving mesh method(r-method)is used to accurately capture complex underwater shock wave systems.Multiple numerical experiments are conducted,including deep-water explosions,near-surface explosions for both spherical charge and cylindrical charge,and regular–irregular reflection interface calculations.The results show that compared to the fixed mesh method,the adaptive mesh method provides results closer to the theoretical values and achieves local high-resolution computation of multi-material fluids.By adjusting the adaptive function,different mesh refinement effects can be obtained.This method also has certain advantages in calculating the regular–irregular reflection interface in underwater explosions.This study establishes a validated computational framework for underwater explosion research,enhancing the predictive accuracy for underwater shock wave propagation in engineering assessments and providing new insights into the fundamental physics of multi-material explosion phenomena. 展开更多
关键词 adaptive mesh shock wave five equations underwater
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Automated Pipe Defect Identification in Underwater Robot Imagery with Deep Learning 被引量:1
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作者 Mansour Taheri Andani Farhad Ameri 《哈尔滨工程大学学报(英文版)》 2026年第1期197-215,共19页
Underwater pipeline inspection plays a vital role in the proactive maintenance and management of critical marine infrastructure and subaquatic systems.However,the inspection of underwater pipelines presents a challeng... Underwater pipeline inspection plays a vital role in the proactive maintenance and management of critical marine infrastructure and subaquatic systems.However,the inspection of underwater pipelines presents a challenge due to factors such as light scattering,absorption,restricted visibility,and ambient noise.The advancement of deep learning has introduced powerful techniques for processing large amounts of unstructured and imperfect data collected from underwater environments.This study evaluated the efficacy of the You Only Look Once(YOLO)algorithm,a real-time object detection and localization model based on convolutional neural networks,in identifying and classifying various types of pipeline defects in underwater settings.YOLOv8,the latest evolution in the YOLO family,integrates advanced capabilities,such as anchor-free detection,a cross-stage partial network backbone for efficient feature extraction,and a feature pyramid network+path aggregation network neck for robust multi-scale object detection,which make it particularly well-suited for complex underwater environments.Due to the lack of suitable open-access datasets for underwater pipeline defects,a custom dataset was captured using a remotely operated vehicle in a controlled environment.This application has the following assets available for use.Extensive experimentation demonstrated that YOLOv8 X-Large consistently outperformed other models in terms of pipe defect detection and classification and achieved a strong balance between precision and recall in identifying pipeline cracks,rust,corners,defective welds,flanges,tapes,and holes.This research establishes the baseline performance of YOLOv8 for underwater defect detection and showcases its potential to enhance the reliability and efficiency of pipeline inspection tasks in challenging underwater environments. 展开更多
关键词 YOLO8 underwater robot Object detection underwater pipelines Remotely operated vehicle Deep learning
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A review of the surface activation and modification of biochars
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作者 Zhang Yihan Chen Longyi 《新型炭材料(中英文)》 北大核心 2026年第1期67-90,共24页
Biomass-derived carbon materials are favored for their abundance and sustainability,and ease of preparation and modification.By surface activation and modification they can have a good electrical conductivity,excellen... Biomass-derived carbon materials are favored for their abundance and sustainability,and ease of preparation and modification.By surface activation and modification they can have a good electrical conductivity,excellent catalytic activity,a remarkable adsorption capacity,and different interfacial physicochemical functionalities.Surface-modified biochars have found wide applications in energy storage,environmental remediation,and catalysis.However,achieving precise and controllable modification of their active sites remains a challenge.Recent advances and future prospects for controlling their surface morphology,defect engineering,and surface coating strategies,with particular attention to their means of fabrication,are reviewed. 展开更多
关键词 Activation and modification Carbon material interface surface functionalization Metal nanoparticle deposition surface defect
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Underwater Image Enhancement Based on Depthwise Separable Convolution-Based Generative Adversarial Network
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作者 ZENG Jun-yang SI Zhan-jun 《印刷与数字媒体技术研究》 北大核心 2026年第1期60-66,共7页
The existence of absorption and reflection of light underwater leads to problems such as color distortion and blue-green bias in underwater images.In this study,a depthwise separable convolution-based generative adver... The existence of absorption and reflection of light underwater leads to problems such as color distortion and blue-green bias in underwater images.In this study,a depthwise separable convolution-based generative adversarial network(GAN)algorithm was proposed.Taking GAN as the basic framework,it combined a depthwise separable convolution module,attention mechanism,and reconstructed convolution module to realize the enhancement of underwater degraded images.Multi-scale features were captured by the depthwise separable convolution module,and the attention mechanism was utilized to enhance attention to important features.The reconstructed convolution module further extracts and fuses local and global features.Experimental results showed that the algorithm performs well in improving the color bias and blurring of underwater images,with PSNR reaching 27.835,SSIM reaching 0.883,UIQM reaching 3.205,and UCIQE reaching 0.713.The enhanced image outperforms the comparison algorithm in both subjective and objective metrics. 展开更多
关键词 underwater image enhancement Generating adversarial network Depthwise separable convolution
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A standardized dataset of CO-TPD spectra on transitionmetal single-crystal surfaces
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作者 YANG Lin WU Jianghong WANG He 《燃料化学学报(中英文)》 北大核心 2026年第4期180-190,共11页
Temperature-programmed desorption(TPD)is a fundamental technique in surface science and heterogeneous catalysis for characterizing adsorption behavior,and for extracting key parameters such as adsorption energy.Howeve... Temperature-programmed desorption(TPD)is a fundamental technique in surface science and heterogeneous catalysis for characterizing adsorption behavior,and for extracting key parameters such as adsorption energy.However,the majority of existing TPD data is accessible in the form of published images,which lacks structured and quantitative datasets.This constrains its utility for rigorous quantitative analysis and computational modelling.Using carbon monoxide(CO)which is a widely adopted probe molecule,a curated and standardized dataset of CO-TPD is constructed,encompassing 14 transition-metal single-crystal surfaces,including copper(Cu)and ruthenium(Ru).By systematically extracting numerical data points from published spectra and applying normalization,essential spectral features such as peak shape are fully preserved.The dataset also documents relevant experimental parameters,including heating rates,and was developed using a standardized protocol for data collection and quality control.This resource serves as both a reference library to support the deconvolution of TPD spectra from complex catalysts and an experimental benchmark for calibrating parameters in theoretical models.By providing a reliable and accessible data function,this work advances the microscopic understanding and the rational design of catalyst active centers. 展开更多
关键词 CO-TPD standardized dataset transition metal single-crystal surfaces
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An Efficient and Dynamic Framework for Multi-Scale Target Detection of Underwater Organisms
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作者 LI Zhuang LI Guixiang +1 位作者 SONG Xiangyang WANG Xinhua 《Journal of Ocean University of China》 2026年第1期150-160,共11页
The continuous decrease in global fishery resources has increased the importance of precise and efficient underwater fish monitoring technology.First,this study proposes an improved underwater target detection framewo... The continuous decrease in global fishery resources has increased the importance of precise and efficient underwater fish monitoring technology.First,this study proposes an improved underwater target detection framework based on YOLOv8,with the aim of enhancing detection accuracy and the ability to recognize multi-scale targets in blurry and complex underwater environments.A streamlined Vision Transformer(ViT)model is used as the feature extraction backbone,which retains global self-attention feature extraction and accelerates training efficiency.In addition,a detection head named Dynamic Head(DyHead)is introduced,which enhances the efficiency of processing various target sizes through multi-scale feature fusion and adaptive attention modules.Furthermore,a dynamic loss function adjustment method called SlideLoss is employed.This method utilizes sliding window technology to adaptively adjust parameters,which optimizes the detection of challenging targets.The experimental results on the RUOD dataset show that the proposed improved model not only significantly enhances the accuracy of target detection but also increases the efficiency of target detection. 展开更多
关键词 underwater target detection complex underwater environment YOLOv8 object detection
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Theoretical insights into the hydrogen peroxide oxidation and reduction reactions on low-index Pt surfaces
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作者 WANG Qi CHEN Lifang +1 位作者 DING Ruimin YIN Xi 《燃料化学学报(中英文)》 北大核心 2026年第1期35-45,共11页
Hydrogen peroxide(H_(2)O_(2))oxidation and reduction reactions(HPOR/HPRR)are pivotal in various innovative electrochemical energy conversion devices.A comprehensive understanding of these mechanisms is critical for ca... Hydrogen peroxide(H_(2)O_(2))oxidation and reduction reactions(HPOR/HPRR)are pivotal in various innovative electrochemical energy conversion devices.A comprehensive understanding of these mechanisms is critical for catalyst design and performance improvement in these applications.In this work,we systematically investigate the HPOR/HPRR mechanisms on low-index Pt surfaces,specifically Pt(111),Pt(100)and Pt(110),through density functional theory(DFT)calculations combined with the computational hydrogen electrode(CHE)model.For HPOR,all the low-index Pt surfaces exhibit a unified potential-determining step(PDS)involving the electrochemical oxidation of hydroperoxyl intermediates(HOO*).The binding free energy of HOO*(Δ_(GHOO*))emerges as an activity descriptor,with Pt(110)exhibiting the highest HPOR activity.The HPRR mechanism follows a chem-electrochemical(C-EC)pathway.The rate-determining step(RDS)of HPRR is either the cleavage of the HO-OH bond(chemical)or the reduction of HO(electrochemical),depending on their respective activation energies.These activation energies are functions of the HO*binding free energy,Δ_(GHO*),establishingΔ_(GHO*)as the descriptor for HPRR activity prediction.Pt(111)and Pt(100)are identified as the most active HPRR catalysts among the studied metal surfaces,although they still experience a significant overpotential.The scaling relationship betweenΔ_(GHOO*)andΔ_(GHO*)reveals a thermodynamic coupling of HPOR and HPRR,explaining their occurrence on Pt surfaces.These findings provide important insights and activity descriptors for both HPOR and HPRR,providing valuable guidance for the design of electrocatalysts in H_(2)O_(2)-related energy applications and fuel cells. 展开更多
关键词 HPOR HPRR Pt low-index surfaces density functional theory
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Enhancing Underwater Monocular Depth Estimation with Lpg-Lap Unet for Target Tracking Mission
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作者 YAO Peng WANG Yalu 《Journal of Ocean University of China》 2026年第1期161-170,共10页
Accurately estimating depth from underwater monocular images is essential for the target tracking task of unmanned underwater vehicles.This work proposes a method based on the Lpg-Lap Unet architecture.First,the Unet ... Accurately estimating depth from underwater monocular images is essential for the target tracking task of unmanned underwater vehicles.This work proposes a method based on the Lpg-Lap Unet architecture.First,the Unet architecture integrates Laplacian pyramid depth residuals and Sobel operators to improve the boundary details in depth images,which may suffer from the feature loss caused by upsampling and the blurriness of underwater images.Multiscale local planar guidance layers then fully exploit the intermediate depth features,and a comprehensive loss function ensures robustness and accuracy.Experimental results on benchmarks demonstrate the effectiveness of Lpg-Lap Unet and its superior performance over state-of-the-art models.An underwater target tracking system is then designed to further validate its real-time capabilities in the AirSim simulation platform. 展开更多
关键词 underwater monocular depth estimation Laplacian pyramid multiscale local planar guidance underwater target tracking
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Assessing Surface Roughness between Unishade and Conventional Composite Resins after Immersion in Different Staining Solutions: An In-Vitro Study
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作者 Sultan Binalrimal Abdullah M.Alshehri +3 位作者 Mohammed Mustafa Ali Robaian Alqahtani Rasha Alharthi Basil Almutairi 《Journal of Polymer Materials》 2026年第1期328-341,共14页
Composite resin restorations are routinely exposed to acidic and chromogenic beverages that may alter their surface integrity over time.This in-vitro study evaluated the surface roughness behavior of two universal sin... Composite resin restorations are routinely exposed to acidic and chromogenic beverages that may alter their surface integrity over time.This in-vitro study evaluated the surface roughness behavior of two universal single-shade(Unishade)composites and two conventionalmulti-shade composites following immersion in commonly consumed staining solutions and assessed whether repolishing could restore smoothness after degradation.A total of 120 standardized disc specimens were fabricated and allocated to fourmaterial groups,with each group subdivided into distilled water,cola,and coffee immersion subgroups.Surface roughness was recorded at baseline,after one week,after one month,and following a final repolishing step using a standardized multi-step system.The findings demonstrated that Unishade composites exhibited more stable surface characteristics across all immersion periods,with changes consistently remaining below the threshold associated with biofilm accumulation.Conventional composites showed greater variability,particularly in cola,where roughness values increased significantly compared with distilled water and coffee.Repolishing substantially reduced immersion-induced roughness in all materials,although its effectiveness varied depending on composite formulation and beverage acidity.Cola produced the greatest surface alterations across all groups,highlighting the erosive potential of low-pH beverages.These results indicate that Unishade composites possess superior resistance to surface degradation,likely due to their nano-structured filler configuration and less hydrophilic resin matrices,while conventional materials appear more susceptible to acidic challenge.Within the limitations of this study,selecting surface-stable material types and applying appropriate finishing and repolishing protocols may enhance the long-term performance and esthetics of composite restorations. 展开更多
关键词 Composite resins surface integrity surface roughness surface damage staining solutions
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Motion Planning of an Autonomous Underwater Vehicle via the Integrated Design of Detection,Communication and Control
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作者 Tianyi Guo Jing Yan +2 位作者 Xian Yang Tianyi Zhang Xinping Guan 《IEEE/CAA Journal of Automatica Sinica》 2026年第1期218-220,共3页
Dear Editor,This letter studies the motion planning issue for an autonomous underwater vehicle(AUV)in obstacle environment.We propose a novel integrated detection-communication waveform that enables simultaneous obsta... Dear Editor,This letter studies the motion planning issue for an autonomous underwater vehicle(AUV)in obstacle environment.We propose a novel integrated detection-communication waveform that enables simultaneous obstacle detection and self-localization. 展开更多
关键词 communication waveform motion planning obstacle detection autonomous underwater vehicle integrated detection simultaneous obstacle detection autonomous underwater vehicle auv obstacle environment
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Marine Shell-Inspired Laser Surface Texturing:Characterizing the Surface Properties of Co-Based Alloy
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作者 Şefika Kasman Sertan Ozan 《Journal of Bionic Engineering》 2026年第1期341-353,共13页
This study investigated surface roughness,the wettability behavior,and surface energy of Co-based alloy specimens textured using the biomimetic Laser Surface Texturing(LST)method.The surface texture was inspired by th... This study investigated surface roughness,the wettability behavior,and surface energy of Co-based alloy specimens textured using the biomimetic Laser Surface Texturing(LST)method.The surface texture was inspired by the patterns found on marine shells.The impacts of the parameters on wettability,Surface Free Energy(SFE),surface topography,and texture roughness generated by the laser beam tracking a spiral path were investigated.Reducing spiral pitch produces more complicated and chaotic surface patterns.Most surfaces are hydrophobic,and surface roughness and topography influence the Contact Angle(CA).Topography and roughness were affected by frequency and scanning speed;a decrease in scanning speed and frequency generated more chaotic and irregular surface textures.With general factorial analysis and Analysis of Variance(ANOVA),our statistical study reveals that accounting for 88%of the influence,the scanning speed is the primary factor influencing surface roughness.On the other hand,the spiral pitch is essential for defining the struc-tural features of the surface,even if it less influences roughness.The SFE of laser-textured CoCr28Mo alloy specimens was optimizable within the range of 14-32 mN/m.The relevant findings offer valuable insights into optimizing LST for the specific surface properties of the Co-based alloy. 展开更多
关键词 Bio-inspired surface CoCr28Mo alloy WETTABILITY surface roughness surface free energy
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Simplified semi-analytical solutions for dynamic responses of composite cylinders subjected to far-field underwater explosions
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作者 Ye Pyae Sone Oo Kevin Brochard HervéLe Sourne 《Defence Technology(防务技术)》 2026年第3期183-201,共19页
This paper presents a simplified design tool based on semi-analytical formulations to investigate the dynamic response of an immersed composite cylinder subjected to a far-field underwater explosion.The cylinder is si... This paper presents a simplified design tool based on semi-analytical formulations to investigate the dynamic response of an immersed composite cylinder subjected to a far-field underwater explosion.The cylinder is simply supported,fully submerged and filled with air inside.A classical shell theory using a Double Fourier series solution combined with the first-order Doubly Asymptotic Approximation(DAA1)formulation is adapted to model the fluid-structure interaction.An explicit non-standard finite difference scheme is applied to solve the coupled differential equations in time domain.The validity of DAA1 model is established by comparing the LS-DYNA/USA finite element results with existing experimental data from the literature.Then the proposed semi-analytical solutions are compared to the LS-DYNA/USA results,showing good correlation with a discrepancy of 7%for peak deflections and±9%for maximum stresses at the stand-off point for cylinders with relatively small length over radius ratios.Parametric studies examining the effect of different loading conditions,areal masses,and material configurations reveal that a large charge mass located far from the composite panel turns out to be more damaging than a small mass located nearby due to a broader pressure-time profile.Finally,the proposed model demonstrates a significant reduction in computation time,being approximately 30 times faster than its numerical counterpart,LS-DYNA/USA,making it a valuable tool for the preliminary design stages. 展开更多
关键词 Fluid-structure interaction(FSI) underwater explosion(UNDEX) underwater shock analysis(USA) Composite cylinders Doubly asymptotic approximation(DAA)
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Numerical Study on the Correlation Between Underwater Radiated Noise and Wake Evolution of a Rim-Driven Thruster
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作者 Jie Gong Zhongwan Wu 《哈尔滨工程大学学报(英文版)》 2026年第1期15-31,共17页
In this investigation,a hybrid approach integrating the IDDES turbulence model and FW-H is employed to forecast the hydroacoustic of the rim driven thruster(RDT)under non-cavitation and uniform flow conditions at vary... In this investigation,a hybrid approach integrating the IDDES turbulence model and FW-H is employed to forecast the hydroacoustic of the rim driven thruster(RDT)under non-cavitation and uniform flow conditions at varying loading conditions(J=0.3 and J=0.6).It is revealed that the quadrupole term contribution in the P-FWH method significantly affects the monopole term in the low-frequency region,while it mainly affects the dipole term in the high-frequency region.Specifically,the overall sound pressure levels(SPL)of the RDT using the P-FWH method are 2.27 dB,10.03 dB,and 16.73 dB at the receiving points from R1 to R3 under the heavy-loaded condition,while they increase by 0.67 dB at R1,and decrease by 14.93 dB at R2,and 22.20 dB at R3,for the light-loaded condition.The study also utilizes the pressure-time derivatives to visualize the numerical noise and to pinpoint the dynamics of the vortex cores,and the optimization of the grid design can significantly reduce the numerical noise.The computational accuracy of the P-FWH method can meet the noise requirements for the preliminary design of rim driven thrusters. 展开更多
关键词 Rim-driven thruster HYDRODYNAMICS underwater radiated noise Non-cavitation Numerical noise
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Spatiotemporal variations of surface water and its response to climate change in global arid regions during 2000–2020
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作者 TIAN Yanjun SUN Yongqi +2 位作者 HOU Senlei GAO Yongnian ERKIN Shireli 《Journal of Arid Land》 2026年第4期568-583,共16页
Surface water plays an essential role in the ecohydrological cycle,especially in water-scarce regions.Changes in surface water restrict social,economic,and agricultural development.However,the patterns and underlying ... Surface water plays an essential role in the ecohydrological cycle,especially in water-scarce regions.Changes in surface water restrict social,economic,and agricultural development.However,the patterns and underlying causes of surface water changes over varying frequencies in global arid regions remain unclear.Thus,this study investigated the changes in surface water and the underlying causes using the trend analysis and Spearman correlation coefficient on the basis of multi-source remote sensing and climate datasets across global arid regions during 2000–2020.The surface water was divided into temporary surface water(TSW),seasonal surface water(SSW),and permanent surface water(PSW)by calculating the surface water inundation frequency.Considering that surface water may be influenced by precipitation in the upper basins,we analyzed the response of surface water area to climatic factors at the basin scale.The area of all surface water(ASW)increased dramatically in global arid regions from 2000 to 2020,increasing from 61.88×104 to 67.40×104 km^(2);however,this increase was accompanied by a decrease in surface water inundation frequency.TSW increased by 55.46%relative to its area in 2000,with a net change rate of 3284.00 km^(2)/a.Changes in surface water were predominantly observed in the Kyzylkum Desert in Central Asia,the Thar Desert in southwestern Asia,and the deserts in Oceania.Precipitation had a significant effect on SSW and TSW at the basin scale.The correlation between precipitation and SSW area can reach 0.808 in the Indus River Basin of the Thar Desert(P<0.01).The findings provide a more comprehensive understanding of surface water variability in global arid regions,carrying significant practical implications for the scientific management of surface water at different frequencies. 展开更多
关键词 surface water area surface water inundation frequency temporary surface water climate change snow melting global arid regions
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Vortex-Induced Vibration Characteristics of an Underwater Manipulator in Pulsating Flow
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作者 Yongqi Li Xia Liu +3 位作者 Zongqiang Li Derong Duan Senliang Dai Hui Zhang 《哈尔滨工程大学学报(英文版)》 2026年第1期63-81,共19页
Vortex-induced vibration(VIV)of an underwater manipulator in pulsating flow presents a notable engineering problem in precise control due to the velocity variation in the flow.This study investigates the VIV response ... Vortex-induced vibration(VIV)of an underwater manipulator in pulsating flow presents a notable engineering problem in precise control due to the velocity variation in the flow.This study investigates the VIV response of an underwater manipulator subjected to pulsating flow,focusing on how different postures affect the behavior of the system.The effects of pulsating parameters and manipulator arrangement on the hydrodynamic coefficient,vibration response,motion trajectory,and vortex shedding behaviors were analyzed.Results indicated that the cross flow vibration displacement in pulsating flow increased by 32.14%compared to uniform flow,inducing a shift in the motion trajectory from a crescent shape to a sideward vase shape.In the absence of interference between the upper and lower arms,the lift coefficient of the manipulator substantially increased with rising pulsating frequency,reaching a maximum increment of 67.0%.This increase in the lift coefficient led to a 67.05%rise in the vibration frequency of the manipulator in the in-line direction.As the pulsating amplitude increased,the drag coefficient of the underwater manipulator rose by 36.79%,but the vibration frequency in the cross-flow direction decreased by 56.26%.Additionally,when the upper and lower arms remained in a state of mutual interference,the cross-flow vibration amplitudes of the upper and lower arms were approximately 1.84 and 4.82 times higher in a circular-elliptical arrangement compared to an elliptical-circular arrangement,respectively.Consequently,the flow field shifted from a P+S pattern to a disordered pattern,disrupting the regularity of the motion trajectory. 展开更多
关键词 underwater manipulator Pulsating flow Vortex-induced vibration TRAJECTORY Overlapping mesh method
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The surface binding and energy issues in the rational design of separators for Li||S batteries
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作者 Hongfang Du Lijing Wang +8 位作者 Shuyu Cheng Chao Wu Sheng Yang Yang Liu Yi Zhao Dandan Cui Shaowei Zhang Shixue Dou Liangxu Lin 《Journal of Energy Chemistry》 2026年第1期987-1013,I0021,共28页
Lithium-sulfur batteries(LSBs)represent a next-generation energy storage technology,but widespread applications are restricted by the shuttle of lithium polysulfides(LiPSs).The rational design of separators has been d... Lithium-sulfur batteries(LSBs)represent a next-generation energy storage technology,but widespread applications are restricted by the shuttle of lithium polysulfides(LiPSs).The rational design of separators has been demonstrated to be one of the most efficient and cost-effective strategies to curb the shuttle effect,and tremendous research progress has been achieved.The efficiency of a separator depends on its interaction with LiPSs,which is governed by the surface energy and binding strength.Despite several review works that have been reported to advance the separators,most of them primarily focus on active material innovation and construction.The most crucial issues of surface binding energy have not been systematically reviewed,limiting the precise design of efficient separators.In this review,fundamentals related to surface energy and binding interactions with LiPSs are comprehensively analyzed and discussed.With surface binding and energy main lines,the advancements in separator engineering strategies are elaborately summarized and discussed.Moreover,techniques for evaluating affinity to LiPSs are thoroughly analyzed to avoid any ambiguities in measurement.Based on the research context,valuable research directions are suggested to construct efficient separators.This work provides guidelines to regulate the surface binding and energy of separators for high-performance LSBs. 展开更多
关键词 Lithium-sulfur batteries SEPARATOR surface binding affinity surface energy Rational design
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Dynamic behavior and damage evaluation of prototype caisson wharf against underwater explosion
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作者 Ziqi Chen Yudi Zhou +1 位作者 Yuehua Cheng Hao Wu 《Defence Technology(防务技术)》 2026年第3期246-266,共21页
Gravity-caisson wharves have been widely constructed in coastal and island regions, which are threaten by potential underwater explosions. This work aims to study the dynamic behaviors and propose a damage evaluation ... Gravity-caisson wharves have been widely constructed in coastal and island regions, which are threaten by potential underwater explosions. This work aims to study the dynamic behaviors and propose a damage evaluation approach of caisson wharf against underwater explosion. Firstly, based on both the underwater explosion loading test and underwater explosion test on the reduced-scale caisson specimen, a high-fidelity finite element analysis approach for numerically reproduce the dynamic behaviors of prototype caisson wharves against underwater explosions was proposed and verified. Secondly, the underwater explosion loadings and dynamic behaviors of prototype caisson wharf (14.9 m×8.1 m×10.95 m) against sequential blast wave and bubble pulsation of typical torpedo with a charge weight of 200 kg were studied. The influences of the seabed and cabin infill materials, as well as the explosion standoff distances of 3.4–10.2 m and depths of burst between 1/4 and 3/4 of water depth, on the blast resistance of caisson wharf were further examined through deflection distributions of exterior wall, damage evolution, and overall displacement of caisson wharf. Finally, a performance evaluation approach for prototype caisson wharves against underwater explosions was proposed by comprehensively considering the bearing, storage, and berthing capabilities. The corresponding protective measures and design recommendations were further provided. It indicates that: (i) under the explosion of a typical torpedo, the damage modes of prototype caisson wharf mainly involve the overall vibration, spalling and cracking of the exterior wall, collapse of the upper operating platform and cracking of the top plate;(ii) the blast wave and cavitation zone generated between the bubble and the exterior wall are the two primary causes of damage to caisson wharf;(iii) compared to the saturated calcareous sand seabed, the assumption of rigid seabed underestimates the spalling on the exterior wall, which is not recommended for scenarios where cavitation zones may generate;(iv) rock rubble is the most effective infill material in improving the blast resistance of caisson wharf among four types of infill configurations, i.e., fully filled and half-filled saturated calcareous sand, rock rubble and pure water;(v) the standoff distance of 10.2 m is regarded as a secure protective range in the scenarios discussed currently. As the standoff distance decreases and the depth of burst increases, the spalling of the exterior wall induced by the cavitation intensifies, posing a great threat to the functionality of caisson wharf. 展开更多
关键词 Caisson wharf underwater explosion Blast resistance Performance evaluation Numerical simulation
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Effect of surface area and pore size on long-term bone regeneration:dynamic changes in geometric characteristics,mass transport,and mechanobiology
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作者 Xing Peng Guoxian Zhang +5 位作者 Jian Pu Shu Yang Wen Cui Xue Zhou Shuxin Qu Zhongmin Jin 《Bio-Design and Manufacturing》 2026年第1期137-152,I0021,共17页
The specific surface area(S S)and pore size(D)exhibit an inherent trade-off in the microscale design of bone implants:larger pores typically correlate with reduced surface area and vice versa.This relationship has att... The specific surface area(S S)and pore size(D)exhibit an inherent trade-off in the microscale design of bone implants:larger pores typically correlate with reduced surface area and vice versa.This relationship has attracted notable attention because of its critical role in the regulation of cell adhesion and osteogenesis.However,it remains largely unclear how S S and D affect the generated bone tissue and dynamically change during long-term osteogenesis.Herein,by applying rigorous geometric mapping to minimal surfaces,we constructed precisely partitioned and layer-by-layer thickened tissue models to simulate osteogenesis across different temporal scales and thereby track the dynamic evolution of geometric characteristics,permeability,and mechanobiological tissue differentiation.The high-S S samples were found to facilitate the rapid formation of new bone tissue in the early stages.However,their smaller pores tended to cause occlusions,hindering further tissue development.In contrast,low-S S samples showed slower bone regeneration,but their larger pores provided adequate physical space for tissue regeneration and mass transport,ultimately promoting bone formation in the long term.Mechanobiological regulation suggests that fibrous tissue formation inhibits additional bone formation,establishing a dynamic equilibrium between osteogenesis and pore space to sustain nutrient/waste exchange throughout the regenerative process.Overall,smaller pores are preferable in implants for minimally loaded osteoplasty procedures focused on early-stage bone consolidation,whereas larger pores are preferable in dynamically loaded implants requiring prolonged mechanical stability. 展开更多
关键词 Minimal surface Specific surface area Pore size Bone ingrowth MECHANOBIOLOGY Finite element simulation
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Path planning of unmanned surface vehicles based on improved particle swarm optimization algorithm with consideration of particle sight distance
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作者 WANG Cheng YANG Junnan +3 位作者 ZHANG Xinyang QIAN Zhong ZHU Ye LIU Hong 《上海海事大学学报》 北大核心 2026年第1期9-19,共11页
To enhance the accuracy of path planning of unmanned surface vehicles(USVs),the particle swarm optimization algorithm(PSO)is improved based on species migration strategies observed in ecology.By incorporating the conc... To enhance the accuracy of path planning of unmanned surface vehicles(USVs),the particle swarm optimization algorithm(PSO)is improved based on species migration strategies observed in ecology.By incorporating the concept of particle sight distance,an improved algorithm,called SD-IPSO,is proposed for the real-time autonomous navigation of USVs in marine environments.The algorithm refines the individual behavior pattern of particles in the population,effectively improving both local and global search capabilities while avoiding premature convergence.The effectiveness of the algorithm is validated using standard test functions from CEC-2017 function library,assessing it from multiple dimensions.Sensitivity analysis is conducted on key parameters in the algorithm,including particle sight distance and population size.Results indicate that compared with PSO,SD-IPSO demonstrates significant advantages in optimization accuracy and convergence speed.The application of SD-IPSO in path planning is further investigated through a 14-point traveling salesman problem(TSP)example and navigation autonomous tests of USVs in marine environments.Findings demonstrate that the proposed algorithm exhibits superior optimization capabilities and can effectively address the path planning challenges of USVs. 展开更多
关键词 particle swarm optimization algorithm(PSO) sight distance unmanned surface vehicle(USV)
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