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Digital reconstruction of three-dimensional contours and its application to microstructural evaluation of postblast rock fissure surfaces 认领 引用
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作者 Yanbing Wang Zhaoyang Wang +1 位作者 Dairui Fu Mingwei Gang 《Deep Underground Science and Engineering》 EI CAS CSCD 2025年第2期316-328,共13页
Fracture surface contour study is one of the important requirements for characterization and evaluation of the microstructure of rocks.Based on the improved cube covering method and the 3D contour digital reconstructi... Fracture surface contour study is one of the important requirements for characterization and evaluation of the microstructure of rocks.Based on the improved cube covering method and the 3D contour digital reconstruction model,this study proposes a quantitative microstructure characterization method combining the roughness evaluation index and the 3D fractal dimension to study the change rule of the fracture surface morphology after blasting.This method was applied and validated in the study of the fracture microstructure of the rock after blasting.The results show that the fracture morphology characteristics of the 3D contour digital reconstruction model have good correlation with the changes of the blasting action.The undulation rate of the three-dimensional surface profile of the rock is more prone to dramatic rise and dramatic fall morphology.In terms of tilting trend,the tilting direction also shows gradual disorder,with the tilting angle increasing correspondingly.All the roughness evaluation indexes of the rock fissure surface after blasting show a linear and gradually increasing trend as the distance to the bursting center increases;the difference between the two-dimensional roughness evaluation indexes and the three-dimensional ones of the same micro-area rock samples also becomes increasingly larger,among which the three-dimensional fissure roughness coefficient JRC and the surface roughness ratio Rs display better correlation.Compared with the linear fitting formula of the power function relationship,the three-dimensional fractal dimension of the postblast fissure surface is fitted with the values of JRC and Rs,which renders higher correlation coefficients,and the degree of linear fitting of JRC to the three-dimensional fractal dimension is higher.The fractal characteristics of the blast-affected region form a unity with the three-dimensional roughness evaluation of the fissure surface. 展开更多
关键词 cube covering method evaluation of damage characterization fractal dimension roughness three-dimensional contour scanning
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Oxygenation-driven multimodal photoacoustic/ultrasonic imaging enhances evaluation of enthesitis disease activity in psoriatic arthritis 认领 引用 被引量：1
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作者 Rui Zhang Fan Yang +8 位作者 Chenyang Zhao Ming Wang Yan Zhang Fang Yang Lei Zhu Jianchu Li Yuxin Jiang Xiaomei Leng Meng Yang 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2026年第1期126-138,共13页
Conventional ultrasound(US)evaluation of enthesitis in psoriatic arthritis(PsA)is limited by its inability to quantify metabolic alterations such as hypoxia,a key driver of disease activity.We introduce an oxygenation... Conventional ultrasound(US)evaluation of enthesitis in psoriatic arthritis(PsA)is limited by its inability to quantify metabolic alterations such as hypoxia,a key driver of disease activity.We introduce an oxygenation-integrated multimodal photoacoustic/ultrasound(PA/US)imaging framework designed to quantify entheseal oxygen saturation(SO2)for assessing entheseal disease activity in PsA.In this cross-sectional study,25 PsA patients underwent bilateral PA/US imaging of 12 entheses,where ultrasound lesions were scored using the Outcome Measures in Rheumatology scoring system,and PA-derived SO2 levels,quantified via dual-wavelength PA imaging,were classified into hyperoxia or hypoxia groups using k-means clustering.This approach provides metabolic insights complementary to conventional ultrasonic assessment.A composite score integrating hypoxia with US parameters was validated against clinical disease activity indices(Disease Activity Score 28-C-reactive protein,DAS28-CRP;Disease Activity Index for Psoriatic Arthritis,DAPSA).Among 300 entheses,103(34.3%)exhibited PA positivity,with 40(38.8%)classified as hypoxia.Hypoxia scores independently predicted DAS28-CRP(β=0.618,p=0.001)and DAPSA(β=0.612,p<0:001).The hypoxia-optimized PAUS score demonstrated superior correlation with disease activity indices compared to conventional US(DAS28-CRP:r=0.615,p=0.001 versus r=0.474,p=0.017;DAPSA:r=0.743,p<0:001 versus r=0.567,p=0.003),alongside superior diagnostic accuracy for minimal disease activity(area under the curve,AUC 0.776 versus 0.614,p=0.008)and low disease activity(AUC 0.853 versus 0.772,p=0.009).This multimodal scoring system enhances the stratification of PsA disease activity by providing unique metabolic insights,offering a potential tool for therapeutic monitoring and guiding treat-to-target strategies. 展开更多
关键词 Photoacoustic imaging oxygen saturation enthesis disease activity evaluation
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Three-dimensional cooperative guidance law with practical predefined-time approach angle and time-to-go convergence 认领 引用 被引量：1
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作者 Zihao WU Wei FENG +3 位作者 Xiaofeng ZHANG Wenxing FU Zhang REN Tuo HAN 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2026年第5期530-546,共17页
This paper presents a Three-Dimensional(3D)cooperative guidance law with Practical Predefined-Time(PPT)convergence for multiple missiles considering approach angle(terminal lineof-sight)and simultaneous arrival constr... This paper presents a Three-Dimensional(3D)cooperative guidance law with Practical Predefined-Time(PPT)convergence for multiple missiles considering approach angle(terminal lineof-sight)and simultaneous arrival constraints.To achieve a salvo attack against a maneuvering target from various directions,the guidance problem is tackled by addressing two critical factors:ensuring that the time-of-arrival is consistent and that the desired approach angles can be met.Considering the short duration of the homing guidance process,the convergence with predefined time for guidance states(especially the approach angle and time-to-go)is factored in.First,for the simultaneous arrival,a PPT guidance law is developed,which can meet the same time-to-go convergence rate in the Line-of-Sight(LOS)direction.Then,in the normal LOS direction,a 3D PPT guidance law is presented considering the approach angle constraint so that the desired approach angles can be reached within a user-designed time.The time-based generator technique is employed in the proposed PPT Cooperative Guidance Law(PPTCGL)to avoid the time-varying gain singularity issue.Notably,this technique can allow the convergence time to be preset in advance,independent of initial system conditions and tuning parameters.Additionally,to avoid excessive gain and improve the robustness of guidance law,a PPT disturbance observer is designed against uncertainties and target maneuvers so that the guidance system perturbation can be compensated in real time.It is userfriendly that the convergence of disturbance estimation can be met with a flexible pre-setting time before achieving the terminal guidance constraints.Finally,extensive numerical simulations are conducted to verify the effectiveness and robustness of the proposed PPTCGL in both the nominal cases and the Monte Carlo test. 展开更多
关键词 Approach angle constraint Cooperative guidance law Maneuvering target Practical predefined-time consensus Three-dimensional guidance model
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Multi-source errors evaluation of machine tools:from research gaps to methodologies and applications 认领 引用 被引量：1
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作者 Jingang Sun Yanbin Zhang +14 位作者 Xiao Ma Benkai Li Min Yang Liandi Xu Haiyuan Xin Qinglong An Lida Zhu Qingfeng Bie Xianxin Yin Shouhai Chen Guanqun Li Yusuf Suleiman Dambatta Rui Xue Zhenwei Yu Changhe Li 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2026年第2期44-96,共53页
Multi-source errors,as critical obstacles limiting the accuracy retention and machining performance of machine tools,hold fundamental and strategic significance for achieving high-precision,high-efficiency,and high-re... Multi-source errors,as critical obstacles limiting the accuracy retention and machining performance of machine tools,hold fundamental and strategic significance for achieving high-precision,high-efficiency,and high-reliability machining in modern manufacturing systems.However,these errors typically exhibit complex characteristics such as strong coupling,time-variance,and nonlinearity,which challenge traditional methods of error identification,modeling,and compensation in terms of adaptability,real-time capability,and integration.Therefore,it is imperative to establish a systematic and intelligent multi-source error control framework.Firstly,this work systematically reviews typical error sources and their evolution mechanisms,evaluates multi-scale detection technologies including laser interferometry,double ball-bar systems,multi-sensor fusion,and vision-based systems,and constructs an intelligent error identification and evaluation framework.Next,it reviews classical modeling methods such as homogeneous transformation matrices,screw theory,thermal equilibrium models,finite element analysis,and modal analysis,compares physical modeling,data-driven,and hybrid modeling strategies,and develops an integrated multi-source error modeling architecture centered on digital twin technology and artificial intelligence.Furthermore,key technologies,including geometric error mapping and real-time compensation,online thermal error prediction and active temperature control,dynamic error suppression,and adaptive control,are summarized.A multi-level integrated error compensation architecture is proposed by combining physical models,data models,and cyber-physical synchronization.This architecture encompasses core processes such as error traceability and decoupling,dynamic prediction,real-time compensation,and closed-loop optimization,emphasizing engineering implementation mechanisms based on cyber-physical collaboration,multi-physics coupling,and multi-scale fusion,thereby effectively enhancing accuracy stability and control robustness under complex operating conditions.Finally,frontier challenges such as constructing high-fidelity coupled models from heterogeneous multi-source data,edge-cloud collaborative control,and cross-platform interoperability are discussed.The application prospects of multi-source error evaluation are also envisioned,providing theoretical foundations and technical support for the precise management and optimization of the entire lifecycle accuracy of machine tools. 展开更多
关键词 multi-source error evaluation error coupling integrated error modeling traceability and decoupling hybrid prediction closed-loop error compensation
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Therapeutic effects of low-intensity transcranial focused ultrasound stimulation on ischemic stroke in rats:An in vivo evaluation using electrical impedance tomography 认领 引用 被引量：1
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作者 Jiecheng Guo Sixuan He +4 位作者 Li Yan Lei Wang Xuetao Shi Huijing Hu Le Li 《Neural Regeneration Research》 SCIE CAS CSCD 2026年第3期1183-1190,共8页
Although previous studies have demonstrated that transcranial focused ultrasound stimulation protects the ischemic brain,clear criteria for the stimulation time window and intensity are lacking.Electrical impedance to... Although previous studies have demonstrated that transcranial focused ultrasound stimulation protects the ischemic brain,clear criteria for the stimulation time window and intensity are lacking.Electrical impedance tomography enables real-time monitoring of changes in cerebral blood perfusion within the ischemic brain,but investigating the feasibility of using this method to assess post-stroke rehabilitation in vivo remains critical.In this study,ischemic stroke was induced in rats through middle cerebral artery occlusion surgery.Transcranial focused ultrasound stimulation was used to treat the rat model of ischemia,and electrical impedance tomography was used to measure impedance during both the acute stage of ischemia and the rehabilitation stage following the stimulation.Electrical impedance tomography results indicated that cerebral impedance increased after the onset of ischemia and decreased following transcranial focused ultrasound stimulation.Furthermore,the stimulation promoted motor function recovery,reduced cerebral infarction volume in the rat model of ischemic stroke,and induced the expression of brain-derived neurotrophic factor in the ischemic brain.Our results also revealed a significant correlation between the impedance of the ischemic brain post-intervention and improvements in behavioral scores and infarct volume.This study shows that daily administration of transcranial focused ultrasound stimulation for 20 minutes to the ischemic hemisphere 24 hours after cerebral ischemia enhanced motor recovery in a rat model of ischemia.Additionally,our findings indicate that electrical impedance tomography can serve as a valuable tool for quantitatively evaluating rehabilitation after ischemic stroke in vivo.These findings suggest the feasibility of using impedance data collected via electrical impedance tomography to clinically assess the effects of rehabilitatory interventions for patients with ischemic stroke. 展开更多
关键词 animal model brain stimulation electrical impedance tomography evaluation impedance noninvasive treatment real-time monitoring rehabilitation stroke transcranial focused ultrasound stimulation
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Mechanisms of efficient three-dimensional fracture network construction in deep shale reservoirs via methane multistage explosive fracturing 认领 引用
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作者 Yabo Chai Ning Luo +6 位作者 Jianan Zhou Yucheng Wei Hu Zhang Chen Lin Guangrui Ma Cheng Zhai Yu Wang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2026年第4期2831-2858,共28页
Methane in situ multistage explosive fracturing(MISMEF)presents a promising technique for enhancing complex fracture networks in deep,low-permeability shale reservoirs.This study employed highfidelity3D simulations,in... Methane in situ multistage explosive fracturing(MISMEF)presents a promising technique for enhancing complex fracture networks in deep,low-permeability shale reservoirs.This study employed highfidelity3D simulations,integrating a characteristic methane–oxygen explosion load model with dynamic relaxation and full-restart methods,to elucidate the coupled interactions between explosive loading and in situ stress.A damage-based zoning approach was developed to quantify fracture characteristics,leading to the proposal of a novel dimensionless evaluation index,Fmef.Results showed that in situ stress predominantly suppressed longitudinal fracture growth,while multistage loading effectively enhanced both lateral and longitudinal propagation following a"delayed initiation–accelerated propagation"pattern.Fracture volume exhibited nonlinear amplificationwith increasing stages,and the continuous increase in fractal dimension suggested improved network connectivity.Energy redistribution driven by the coupled effects of in situ stress and staged loading promoted complex network formation near the wellbore,with MISMEF progressively reducing fracture thresholds through rock mass weakening.Fmef analysis confirmedsignificantimprovement in fracture network quality across all stress conditions,particularly under medium to high in situ stress.This work provides critical mechanistic insights and a theoretical foundation for optimizing MISMEF in deep shale reservoir stimulation. 展开更多
关键词 Methane in situ multistage explosive fracturing(mismef) In situ stress Multistage explosion Three-dimensional fracture network Multidimensional evaluation index
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A condition control-based dual-reliability evaluation for structural health monitoring 认领 引用
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作者 Qiuhui XU Shenfang YUAN +1 位作者 Jian CHEN Hutao JING 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2026年第1期247-262,共16页
It is well recognized that Structural Health Monitoring(SHM)reliability evaluation is a key aspect that needs to be urgently addressed to promote the wide application of SHM methods.However,the existing studies typica... It is well recognized that Structural Health Monitoring(SHM)reliability evaluation is a key aspect that needs to be urgently addressed to promote the wide application of SHM methods.However,the existing studies typically transfer the Non-Destructive Testing/Evaluation(NDT/E)reliability metrics to SHM without a systematic analysis of where these metrics originated.Seldom attentions are paid to the evaluation conditions which are very important to apply these metrics.Aimed at this issue,a new condition control-based Dual-Reliability Evaluation(Dual-RE)method for SHM is proposed.This new method is proposed based on a systematic analysis of the whole framework of reliability evaluation from instrument to NDT,and emphasis is paid to the evaluation condition control.Based on these analyses,considering the special online application scenario of SHM,the proposed Dual-RE method contains two key components:Integrated Sensor-based SHM-RE(IS-SHM-RE)and Critical Service Condition-based SHM-RE(CSC-SHM-RE).ISSHM-RE evaluates the reliability of integrated SHM sensor and system themselves under approximate repeatability conditions,while CSC-SHM-RE assesses SHM reliability under the dominant uncertainties during service,namely intermediate conditions.To demonstrate the Dual-RE,crack monitoring by using the Guided Wave-based-SHM(GW-SHM)on aircraft lug structures is taken as a case study.Both the crack detection and sizing performance are evaluated from accuracy and uncertainty. 展开更多
关键词 Crack detection and sizing Dual-reliability evaluation Evaluation condition control Guided wave-based monitoring Reliability evaluation Structural health monitoring
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Research on dynamic three-dimensional terrain correction methods of quantitative inversion for airborne gamma-ray spectrometer 认领 引用
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作者 He-Xi Wu Wei-Cheng Li +6 位作者 Rui Qiu Chao Xiong Yi-Ming Lyu Yi-Qiang Xing De-Hao Zhang Zong-Shuo Tao Yang Wang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2026年第5期199-214,共16页
Aerial surveys are dynamic and continuous processes,and there are different height distributions of the ground in the measurement area,which leads to problems such as overlapping measurement areas and inaccurate altit... Aerial surveys are dynamic and continuous processes,and there are different height distributions of the ground in the measurement area,which leads to problems such as overlapping measurement areas and inaccurate altitude correction during the survey process.Commonly used terrain correction methods are based on the concept of finite elementization of ground surface radioactive sources,using GPS coordinates,radar altitude,and ground elevation distribution information from aerial surveys,combined with the sourceless efficiency calibration method to construct a response matrix,which is then inverted for surface nuclide content.However,most of the sourceless efficiency calibration methods used are numerical calculations that consider the body detector as a point detector and do not consider the changes in intrinsic detection efficiency under different incident directions of gamma rays.Therefore,when the altitude of the measurement area varies significantly or the flight altitude of the aerial survey is relatively low,such sourceless efficiency calibration method calculations tend to have a large bias,which affects the accuracy of the terrain correction.To address the above problems,this study employs a novel sourceless efficiency calibration method based on the Boolean operation of the ray deposition process and simplifies the traditional body source measurement model to a surface source measurement model to achieve fast and accurate efficiency calibration.Then,through the discretization of the measurement process,the static measurement process is superposed as equivalent to the dynamic measurement process,and the dynamic measurement response matrix is built and optimized based on the calibration method.Finally,the PSO-MLEM algorithm was used to solve the dynamic measurement response matrix to achieve dynamic terrain correction of aerial survey data.Analysis of the Baiyun'ebo test area revealed that,after applying dynamic terrain correction,the inverted anomalies in uranium(eU),thorium(eTh),and potassium(K)concentrations were closer to ground measurements(within 5.72%-30.79%)and exhibited clearer anomaly boundaries compared to traditional height-based corrections.However,owing to the inherent statistical fluctuations and characteristics of matrix inversion,higher measurement values tend to absorb lower ones,potentially enlarging the anomalous regions.Nevertheless,the highanomaly regions after inversion largely coincided with the ground truth validation,demonstrating that the proposed method can effectively correct airborne gamma spectrometry data. 展开更多
关键词 Airborne gamma-ray spectrum Dynamic three-dimensional Terrain correction
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Characteristics of three-dimensional oceanic eddy in the Southern Ocean from 2021 to 2023 认领 引用
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作者 Tao Jiang Weizeng Shao +3 位作者 Yuyi Hu Xingwei Jiang Qingping Zou Yongliang Wei 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2026年第4期1-16,共16页
This study explores the three-dimensional(3-D)characteristics of oceanic eddies in the Southern Ocean from 2021 to 2023.Copernicus Marine Environment Monitoring Service(CMEMS)GLORYS12V1 product,which provides daily cu... This study explores the three-dimensional(3-D)characteristics of oceanic eddies in the Southern Ocean from 2021 to 2023.Copernicus Marine Environment Monitoring Service(CMEMS)GLORYS12V1 product,which provides daily current field data at a(1/12)°grid resolution,is used to identify eddies with radii>10 km.Additionally,the daily sea level anomaly product from Haiyang-2(HY-2)altimeters is used to detect mesoscale eddies with radii>40 km.GLORYS12V1 detects over ten times more surface eddies than HY-2,likely due to its higher spatial and temporal resolution,which allows better identification of smaller-scale features.Both eddy radius and eddy kinetic energy(EKE)differences between layers decrease with depth.At 0.5 m,EKE is lower than at 300–600 m,where it stabilizes.Over 90%of eddies at these depths show center deflection angles under 3°,defined as the angular offset between eddy centers in adjacent layers relative to the vertical(0°)axis.In a 3-D eddy,the center may shift with depth due to physical processes,causing non-zero center deflection angles between layers.Below 300 m,eddy radius differences are more frequently under 20 km than in the upper 0.5–300 m,where baroclinic instability amplifies,and barotropic instability suppresses cross-layer variability.The influence of both instabilities weakens with depth.In the upper ocean(0.5–300 m),baroclinic instability increases the angular offsets between eddy centers.In contrast,barotropic instability reduces these offsets.At 300–600 m,both promote better vertical alignment,indicating greater structural stability.Overall,this study enhances the understanding of the vertical structure and dynamics of oceanic eddies in the Southern Ocean. 展开更多
关键词 three-dimensional characteristics oceanic eddy Southern Ocean
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Three-dimensional full-scale neutronics/thermal-hydraulics/mechanics coupling analysis-based structural assessment of helium-cooled ceramic breeder blanket for fusion reactor 认领 引用
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作者 Qiang Lian Kui Zhang +6 位作者 Shan-Shan Bu Liang-Ming Pan Wen-Xi Tian Sui-Zheng Qiu Guang-Hui Su Xing-Hua Wu Xiao-Yu Wang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2026年第6期178-195,共18页
To accelerate the development and utilization of fusion energy,the China Fusion Engineering Test Reactor(CFETR)has been proposed as a bridge between the International Thermonuclear Experimental Reactor and demonstrati... To accelerate the development and utilization of fusion energy,the China Fusion Engineering Test Reactor(CFETR)has been proposed as a bridge between the International Thermonuclear Experimental Reactor and demonstration fusion reactors.The primary objective of the CFETR is to achieve fusion energy transformation and tritium self-sufficiency,which is realized through the function of the blanket.In this study,a neutronicshermal-hydraulics/mechanics coupling method is developed and applied to a helium-cooled ceramic breeder(HCCB)blanket,which is one of the two blanket candidates for the CFETR.A three-dimensional full-scale model is utilized in the coupling analysis to obtain the distributions of the neutronic,thermal-hydraulic,and mechanical parameters.A structural assessment of the CFETR HCCB blanket is then conducted considering steady-state conditions and two transient scenarios.The results demonstrate that following optimization of the blanket structure,the maximum temperatures of the different components remain below the safety limit of the corresponding materials.The structural assessment indicates that the blanket maintains its structural integrity under steady-state conditions.However,immediately after an in-box loss-of-coolant accident,structural failure owing to stress concentration may occur.Additionally,in the early stage of a loss-of-flow accident,the stress at the joint point between the cooling plate and cap exceeds the allowable stress of the material,potentially leading to structural failure within 17 s if no protective response is implemented.These findings provide comprehensive insights into the performance and safety of the CFETR HCCB blanket design. 展开更多
关键词 Structural assessment Fusion blanket Three-dimensional full-scale model Coupling analysis CFETR
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Data-and knowledge-driven three-dimensional geological reconstruction method for tunnel engineering 认领 引用
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作者 Qiming Li Qian Fang +2 位作者 Jun Wang Gan Wang Peipei Shang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2026年第6期4318-4336,共19页
The creation of a three-dimensional(3D)geological model plays a crucial guiding role in engineering.However,in practice,due to the sparsity of boreholes and the invisibility of strata,accurately reconstructing a 3D ge... The creation of a three-dimensional(3D)geological model plays a crucial guiding role in engineering.However,in practice,due to the sparsity of boreholes and the invisibility of strata,accurately reconstructing a 3D geological model has always been a challenging task.In this study,a data-and knowledge-driven 3D geological reconstruction method is proposed,where the Inverse Distance Weighting(IDW)method is integrated with computer vision techniques to improve the accuracy and reliability of geological modeling.The reconstruction of the geological model is realized by the reconstruction of continuous cross-sections in one direction.The reconstruction method integrates two deep learning models:a repair model that learns stratigraphic relationships from borehole data to reconstruct cross-sections,and an interpolation model that predicts intermediate sections by capturing stratigraphic distribution and variation patterns.The comparison with the IDW method and the ordinary kriging method on the virtual data verifies that the proposed method can capture the spatial distribution characteristics of the strata.An engineering example proves that the proposed method can be successfully applied to complex stratum modeling.The proposed method enhances and facilitates intuitive observation of both the reconstructed results and their uncertainties.The proposed method can provide guidance for underground engineering construction sites and contribute to their digital transformation. 展开更多
关键词 Three-dimensional geological modeling Machine learning Borehole data Stratigraphic uncertainty Voxel model
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The three-dimensional meshfree numerical manifold method based on parallel computing 认领 引用
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作者 Keqin Zhang Wei Wu +2 位作者 Danfeng Zhang Yanfei Kang Hehua Zhu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2026年第2期360-371,共12页
The numerical manifold method,extensively utilized in numerical computations,faces significant challenges in generating complex manifold elements,particularly for three-dimensional applications.To overcome this challe... The numerical manifold method,extensively utilized in numerical computations,faces significant challenges in generating complex manifold elements,particularly for three-dimensional applications.To overcome this challenge,the meshfree numerical manifold method is developed by integrating the moving least-squares method into the numerical manifold method,effectively bypassing the need for meshing complex geometric objects.However,the implementation of the moving least-squares method introduces computational efficiency issues.To mitigate these,parallel computing methods have been incorporated,resulting in a tenfold increase in the speed of assembling the stiffness matrix with central processing unit parallelism,and a twentyfold increase with graphics processing unit parallelism.The static mechanical system equations for the meshfree numerical manifold method are derived using the Galerkin method.The method’s effectiveness and accuracy are then validated through a series of numerical experiments.The experiments demonstrated that the meshfree numerical manifold method achieves a high precision with minimal nodes and integration points.Additionally,positioning nodes outside the domain significantly improves computational accuracy at the boundaries. 展开更多
关键词 Meshfree numerical manifold method Three-dimensional computation Parallel computation Elastostatics Moving least-squares
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Comprehensive evaluation of seed iron content in peanut germplasm and identification of elite genotypes with high iron 认领 引用
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作者 Jianbin Guo Li Huang +7 位作者 Huaiyong Luo Weigang Chen Bolun Yu Xiaojing Zhou Huifang Jiang Boshou Liao Yong Lei Nian Liu 《Oil Crop Science》 CAS CSCD 2026年第1期38-44,共7页
Iron is an essential mineral element that plays important roles in plant growth,development,and human health.Peanut is a valuable source of iron for human nutrition.Improving iron content in peanut seeds can enhance b... Iron is an essential mineral element that plays important roles in plant growth,development,and human health.Peanut is a valuable source of iron for human nutrition.Improving iron content in peanut seeds can enhance both yield potential and nutritional value.In this study,the seed iron content of the 401 peanut germplasm accessions was estimated and substantial variation among these accessions was observed,ranging from 9.02 to 50.60 mg/kg.The seed iron content of valencia type accessions was significantly higher than that of Peruvian,Virginia,and Irregular types.Landraces showed the highest average iron content,followed by advanced cultivars,breeding lines and interspecific hybrid cultivars.Accessions with red seed coat exhibited significantly higher iron content compared with those with pink seed coat.Correlation analysis revealed that the seed iron content significantly negatively correlated with hundred seed weight(HSW),resveratrol and oleic acid.Eight accessions with high iron content were identified with an average iron content of 32.46 mg/kg,including two elite genotypes that Zh.h4280 showed high resveratrol levels(1057.34μg/kg)and Zh.h1976 exhibited large seeds(HSW over 90g).Association analysis identified four markers,one of which,AHGS2053 stably explained with 5.75%–5.84%phenotypic variation.Accessions containing the favorable allele AHGS2053-250bp exhibited significantly higher iron content compared to those with alternative alleles.The results provide valuable germplasm resources and associated markers for breeding programs targeting high iron content in peanuts. 展开更多
关键词 Peanut Iron content Germplasm accessions Comprehensive evaluation
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Dynamic conditions and processes of three-dimensional accumulation of Sinian-Permian natural gas in Penglai gas area,central Sichuan Basin,SW China 认领 引用
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作者 LUO Bing ZHANG Benjian +8 位作者 ZHOU Gang WU Luya YAN Wei ZHANG Baoshou ZHANG Xihua ZHONG Yuan MA Kui LUO Xiaorong LI Yishu 《Petroleum Exploration and Development》 SCIE 2026年第2期327-342,共16页
Considering the complexities of gas-water relationships in the gas reservoirs,unclear natural gas distribution and difficult exploration expansion of the Sinian–Permian natural gas in the Penglai gas area of the cent... Considering the complexities of gas-water relationships in the gas reservoirs,unclear natural gas distribution and difficult exploration expansion of the Sinian–Permian natural gas in the Penglai gas area of the central Sichuan Basin,this study investigates the gas source,charging processes and enrichment patterns of gas reservoirs based on reservoir characterization,natural gas geochemical analysis,reservoir testing,well logging-seismic data interpretation,as well as basin modeling and dynamic analysis.The results are obtained in three aspects.First,four sets of highly efficient source rocks are developed beneath the salt of the Triassic Jialingjiang Formation,dominated by the Cambrian source rocks.The reservoirs exhibit strong heterogeneity,with six sets of effective reservoirs being isolated from each other yet dynamically connected.Multi-stage strike-slip fault-related fault-fracture-cavity-unconformity systems constitute the hydrocarbon migration network.Second,overpressure generated by hydrocarbon generation in the Cambrian source rocks drove bidirectional hydrocarbon expulsion from the source kitchen.Multiple sources,including cracked gas from paleo-oil reservoirs and residual hydrocarbons within source rocks,contributed to the hydrocarbon supply.The Sinian–Permian system underwent multiple dynamic hydrocarbon accumulation processes,resulting in the formation of extensive“sweet spots”within multi-layered heterogeneous reservoirs,which were subsequently modified by late-stage gas adjustments to their current form.Third,a three-dimensional accumulation model for deep marine natural gas is established,with multi-source hydrocarbon supply,three-dimensional migration,multi-stage accumulation,dynamic adjustment and lithology-controlled distribution.Large-scale reservoirs within positive structural settings,late-stage structurally stable areas,and slope structures are identified as favorable plays for gas exploration. 展开更多
关键词 Sinian Cambrian Permian natural gas dynamic condition three-dimensional accumulation Penglai gas area Sichuan Basin
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Energy-based evaluation of sandstone brittleness under triaxial compression:Micromechanical damage approach 认领 引用
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作者 Qiaojuan Yu Shigui Du +4 位作者 Rui Yong Zhanyou Luo Changshuo Wang Yuanjun Lv Zeping Zhang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2026年第1期580-592,共13页
Rock brittleness is a critical property in geotechnical and energy engineering,as it directly influences the prediction of rock failure and stability assessment.Although numerous methods have been developed to evaluat... Rock brittleness is a critical property in geotechnical and energy engineering,as it directly influences the prediction of rock failure and stability assessment.Although numerous methods have been developed to evaluate brittleness,many fail to comprehensively account for the impacts of microstructural changes,mineralogical characteristics,and stress conditions on energy evolution during failure.This study proposes a novel approach for brittleness evaluation based on the energy evolution throughout the post-peak failure process,integrating two micromechanical mechanisms:crack propagation and frictional sliding.A new brittleness index is defined as the ratio of generated surface energy to released elastic energy,providing a unified framework for assessing both Class I and Class II mechanical behaviors.The brittleness of cyan,white,and gray sandstones was investigated under various confining pressures and moisture conditions using X-ray diffraction(XRD),scanning electron microscopy(SEM),and conventional triaxial compression(CTC)tests.The results demonstrate that brittleness decreases with increasing confining pressure,due to suppressed crack propagation,and increases under saturated conditions,as moisture enhances crack propagation.By establishing connections between mineral composition,microstructural features,and stress-induced responses,the proposed method overcame limitations of previous approaches and offered a more precise tool for evaluating rock brittleness under diverse environmental scenarios. 展开更多
关键词 Brittleness evaluation Energy evolution Micromechanics Triaxial compression Sandstone Moisture effect
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Dynamic behavior and damage evaluation of prototype caisson wharf against underwater explosion 认领 引用
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作者 Ziqi Chen Yudi Zhou +1 位作者 Yuehua Cheng Hao Wu 《Defence Technology（防务技术）》 SCIE EI CAS CSCD 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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Comprehensive quality evaluation and principal component analysis of Crassostrea gigas from North Yellow Sea,China:characterizing nutritional,flavor,and functional profiles 认领 引用
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作者 Shanqin HUO Jixing PENG +3 位作者 Xinnan ZHAO Yichen LIN Xudong LI Zhijun TAN 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2026年第1期406-418,共13页
Crassostrea gigas has good taste and high nutritional value;however,there are few assessments of comprehensive and panoramic analyses of the nutritional quality of the northern oyster.To study the nutritional characte... Crassostrea gigas has good taste and high nutritional value;however,there are few assessments of comprehensive and panoramic analyses of the nutritional quality of the northern oyster.To study the nutritional characteristics of C.gigas from different sources(ploidy,region,size,and culture mode),C.gigas from various ploidy(diploid and triploid),regions(Rushan,Off-site fattening,and Rongcheng),sizes(small,medium,and large)and culture modes(nearshore and offshore)were selected for comparative analyses.The nutritional components(moisture,protein,fat,and mineral),flavor substances(taste amino acids,nucleotides,and succinic acid),and functional indices(eicosapentaenoic acid(EPA),docosahexaenoic acid(DHA),and taurine)of C.gigas were determined.Principal component analysis(PCA)was used to comprehensively evaluate the oysters and investigate the variations in nutritional quality.The PCA results indicate that protein,essential fatty acids,selenium,zinc,taste amino acids,taurine,EPA,and DHA were core components contributing to 82.25%of the cumulative variance,providing a more comprehensive reflection of the nutrient composition of C.gigas.The extensive quality rankings for the C.gigas were as follows:diploid>triploid,Rushan>fattening>Rongcheng,medium>large>small,and offshore>nearshore.The score rank revealed that diploid oysters of medium-size from Rushan demonstrated superior nutritional quality compared to other tested samples.This is the first comprehensive and systematic investigation of C.gigas in northern China to reveal the feature of nutrients,flavor,and functional components.The study provided data support for the culture,consumption,processing,research,and nutritional quality improvement of oyster industry. 展开更多
关键词 Crassostrea gigas nutritional quality principal component analysis comprehensive evaluation
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Infiltration enhancement mechanism and surface morphology evaluation of ultrasonic-assisted microtextured tool turning Ti-6Al-4V with nanobiolubricant 认领 引用
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作者 Xiaoming Wang Yanbin Zhang +7 位作者 Mingzheng Liu Teng Gao Min Yang Liandi Xu Haiyuan Xin Rui Xue Peiming Xu Changhe Li 《ENGINEERING Mechanical Engineering》 SCIE CAS CSCD 2026年第2期105-128,共24页
Titanium alloy serves as a critical structural material for aircraft and engine components.During the manufacturing of these titanium parts,machining,particularly turning,is a fundamental process.However,continuous tu... Titanium alloy serves as a critical structural material for aircraft and engine components.During the manufacturing of these titanium parts,machining,particularly turning,is a fundamental process.However,continuous turning faces a significant bottleneck:severe tool wear caused by insufficient lubricant infiltration at the tool-workpiece interface and excessive cutting forces.The nanobiolubricant minimum quantity lubrication(NMQL)turning process of biomimetic textured cutting tools empowered by ultrasound is considered to have the potential to solve the problem of tool wear during titanium alloy cutting.Nevertheless,the lubricant infiltration dynamics mechanism and tribological properties under the new process are unclear.Based on this,the synergistic effect of ultrasonic vibration on lubricant infiltration and migration was first analyzed.Subsequently,research has been conducted on the frictional properties and surface damage characteristics of four working conditions:dry cutting,NMQL,textured tool assisted NMQL(T-NMQL),and ultrasonic vibration empowered T-NMQL(UVT-NMQL).Surface roughness,surface morphology,cutting specific energy,chip morphology,and tool wear analysis have also been carried out.Furthermore,wavelet analysis has been introduced to decompose surface roughness signals into high and low frequencies,enriching the quantitative evaluation system for surface damage of titanium alloy cutting workpieces.The average cutting specific energies under dry cutting,NMQL,T-NMQL,and UVT-NMQL conditions were determined to be 2.32,2.18,2.01,and 0.78 J/mm3,respectively.Based on the wavelet decomposition results of surface roughness signals,it was found that the surface damage energy of NMQL,T-NMQL,and UVT-NMQL conditions decreased by 28.84%,67.71%,and 82.12%,respectively,compared to dry cutting conditions.The infiltration enhancement effect of ultrasonic vibration is considered important reasons for reducing damage signal energy.These results provide novel research insights for evaluating surface properties in ultrasonic vibration-assisted machining processes. 展开更多
关键词 turning ultrasonic vibration microtexture minimum quantity lubrication titanium alloy surface evaluation
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Quantitative evaluation of coal fracability based on 3D CT reconstruction and fractal characteristics 认领 引用
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作者 Fanhui Zeng Weixin Yang +3 位作者 Jianchun Guo Ran Zhang Yu Zhang Zhangxing Chen 《Natural Gas Industry B》 2026年第1期60-76,共17页
Fracability is a critical indicator for evaluating the exploration and development potential of coalbed methane reservoirs and assessing the effectiveness of hydraulic fracturing stimulation operations.Its core functi... Fracability is a critical indicator for evaluating the exploration and development potential of coalbed methane reservoirs and assessing the effectiveness of hydraulic fracturing stimulation operations.Its core function is to characterize the complexity of the induced fracture network and the resulting effective stimulated volume.In this study,we quantified fracture area and geometric complexity using true triaxial fracturing experiments and computed tomography three-dimensional(3D)reconstruction technology,combined with the box-counting method to calculate the 3D fractal dimension of the fracture surfaces.The results revealed that the total fracture surface area per unit volume of the stimulated reservoir effectively characterized reservoir fracability;specifically,both a larger total fracture surface area and a higher fractal dimension corresponded to better reservoir fracability.Fracture complexity was enhanced by a decrease in the horizontal principal stress difference or an increase in the injection rate.Under optimal conditions of a 3 MPa stress difference and an injection rate of 60 mL/min,fracability improved by 27.6%.Furthermore,liquid carbon dioxide(CO2)improved fracability by 50.7%compared to using water as the fracturing fluid,a result attributed to its low viscosity and strong diffusion capacity,which activated a greater number of natural fractures.A fracability evaluation model integrating brittleness,fracture toughness,and dimensionless net pressure was developed using regression analysis,which demonstrated high reliability with a strong determination coefficient(R2)of 0.9019.This study clarifies the logical relationships among fracture area,complexity,and fractal dimension,providing a novel method for evaluating the fracability of coal reservoirs. 展开更多
关键词 Coal Fracability evaluation 3D reconstruction Fractal dimension Fracture area
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Comparative evaluation of single-mask and single-shot X-ray phase-contrast and dual-energy computed tomography analyses on soft-tissue phantom 认领 引用
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作者 Chang Li Xiao-Xuan Ren +6 位作者 Liang-Liang Lv Shu-Yi Sun Jian Zhang Yin-Qi Lei Xiao-Dong Pan Cui Zhang Gong-Ping Li 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2026年第5期241-251,共11页
In clinical diagnosis,conventional X-ray absorption-contrast computed tomography(XACT)technology cannot effectively differentiate diseased tissues from the healthy ones.X-ray phase-contrast CT(XPCT)and dual-energy CT(... In clinical diagnosis,conventional X-ray absorption-contrast computed tomography(XACT)technology cannot effectively differentiate diseased tissues from the healthy ones.X-ray phase-contrast CT(XPCT)and dual-energy CT(DECT),emerging X-ray imaging technologies with superior diagnostic capabilities,address this issue through different principles.While both XPCT and DECT have advantages and disadvantages in medical applications,their systematic comparison is lacking.Using GEANT4 and MATLAB,in this study,we established an X-ray phase-contrast imaging(XPCI)model based on single-mask and single-shot edge illumination for fast XPCT imaging,comparing it with DECT on soft-tissue phantom.XACT served as a reference for comparison.The study introduces an evaluation system using statistical measures including absolute error,mean absolute error,structure similarity index measure,peak signal-to-noise ratio,and contrast-to-noise ratio.Results show XPCT images are superior to DECT.The XPCI model can be improved on existing medical CT for widespread medical application. 展开更多
关键词 Comparative evaluation X-ray phase-contrast CT Edge illumination Dual-energy CT GEANT4
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