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Experimental and numerical investigation on the evolution of Taylor-Quinney coefficient in 42CrMo steel 认领 引用
1
作者 Wei Qi Longkang Li +4 位作者 Shengxin Zhu Jianguo Li Manxi Chen Qinglei Zeng Hao-Sen Chen 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2026年第5期239-254,共16页
42CrMo steel was studied in this paper on its thermomechanical behavior when subjected to dynamic compression,utilizing in-situ dynamic tests and crystal plasticity finite element method(CPFEM)simulations.A split Hopk... 42CrMo steel was studied in this paper on its thermomechanical behavior when subjected to dynamic compression,utilizing in-situ dynamic tests and crystal plasticity finite element method(CPFEM)simulations.A split Hopkinson pressure bar,combined with high-speed infrared thermography,was employed to simultaneously record the mechanical response and corresponding temperature evolution,enabling the derivation of the Taylor-Quinney coefficient(TQC).To explore the impact of texture orientation on thermomechanical behavior,a dislocation density-based CPFEM model was applied to analyze the plastic deformation process.The findings demonstrate a satisfactory consistency between numerical predictions and experimental results achieved by the dislocation density-based CPFEM.Simulations of four typical textures demonstrated that texture,through changes in the activated slip systems,significantly influences the evolution of the TQC.These findings contribute valuable insights to the TQC database,enhancing our understanding of material behavior under dynamic loading conditions. 展开更多
关键词 42CrMo Taylor-Quinney coefficient Crystal plasticity Texture effect
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A predictive modeling for the variation of orifice throttling coefficient of hydraulic spool valve caused by erosion behavior 认领 引用
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作者 Xiaochao Liu Dingbo Li +4 位作者 Honghui Liao Peiyao Hou Rui Nie Pengyuan Qi Zongxia Jiao 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2026年第2期323-332,共10页
Hydraulic spool valves are crucial components of hydraulic systems.Solid pollution particles mixed in hydraulic oil could result erosion wear of the valve orifice,then lead to a decrease in the performance of valves.M... Hydraulic spool valves are crucial components of hydraulic systems.Solid pollution particles mixed in hydraulic oil could result erosion wear of the valve orifice,then lead to a decrease in the performance of valves.Most studies focused on analyzing the influencing factors and mechanism of erosion wear,while a few considered its evolution,which is the basis for predicting orifice throttling coefficient.According to the variation of orifice throttling coefficient,compensating control could be applied to the hydraulic valves to improve its control performance,and the service life of the spool could also be predicted.In this study,an orifice erosion rate model using finite element analysis(FEA) simulation was firstly established based on the E/CRC erosion model,which mainly consisted of two easily obtainable parameters in hydraulic systems:spool opening and pressure difference.The orifice throttling coefficient prediction model was further established by combining orifice erosion rate model and worn profile model,which model could predict the throttling coefficient and output flow of hydraulic spool valves in real time.The erosion experiments were carried out,and the worn morphologies of orifice positions were also characterized and analyzed,the results showed that the model could accurately predict the orifice erosion rate and the orifice throttling coefficient,the maximum relative error between the prediction model and the experimental measurements is 9.11%.The findings of this study ensure the accurate prediction of the impact of erosion wear and provide guidance for improving the control performance of hydraulic valves. 展开更多
关键词 Erosion wear Valve orifice Orifice throttling coefficient Finite element analysis
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Experimental investigation of discharge coefficient of a converging nozzle for supercritical kerosene 认领 引用
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作者 Zhisheng WANG Yuguang JIANG +3 位作者 Xudong LONG Rongxiao DONG Jintao JIANG Wei FAN 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2026年第7期313-330,共18页
In advanced aeroengines,hydrocarbon fuel is used as coolant in the thermal management system,which may turn to supercritical before injected into the combustor.Inside the inj ecting nozzle,supercritical hydrocarbon fu... In advanced aeroengines,hydrocarbon fuel is used as coolant in the thermal management system,which may turn to supercritical before injected into the combustor.Inside the inj ecting nozzle,supercritical hydrocarbon fuel may experience phase transition because of the sharp expansion,which triggers violent variations in fuel thermal properties.Thus,conventional nozzle design is faced with serious challenges.In this work,the discharge coefficient(Ca)of a converging nozzle for the supercritical RP-3 aviation kerosene is experimentally investigated,focusing specifically on the effects of violent phase transition on the flow characteristics in advanced aeroengine fuel systems.A high-temperature,high-pressure experimental platform was developed,enabling precise control of the inj ection pressure(1.0-6.6 MPa),temperature(600-740 K),and mass flux(0.40-1.59 kg·cm-2·s-1).Experimental results demonstrate that Cd firstly increases then decreases in the liquid-two phase-supercritical transition,instead of keeping constant.It is noticed part of Cd values with two-phase outflow even exceeds 1,which proves the limitations of conventional isentropic assumptions.Further thermodynamic analysis reveals that fluid density and isentropic compressibility at the nozzle exit are two critical parameters influencing the discharge coefficient.Particularly,isentropic compressibility shows the strongest correlation and is identified as the dominant factor.Finally,a predictive model of Cd is proposed based on the real-fluid thermophysical data and a modified ideal gas framework,the precision of which has been validated in the following conditions:The reduced injection temperature ranges from 1.02 to 1.22,and the reduced injection pressure ranges from 1.0 to 2.92.It reveals deeper understanding of the flow behavior in the liquid-two phase-supercritical transition and provides enhanced guidance for the nozzle design with supercritical kerosene. 展开更多
关键词 Discharge coefficient Isentropic flow Nozzle design RP-3 aviation kerosene Supercritical state
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High-precision color crosstalk coefficient calibration method based on phase error estimation 认领 引用
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作者 FENG Lu-yuan LIANG Jian +3 位作者 WANG Xiang-jun ZHAO Zong-yang CHEN Yi-fan WU Bin 《中国光学（中英文）》 EI CAS CSCD 北大核心 2026年第3期745-753,共9页
Color-coded fringe patterns have emerged as a key technique for enabling real-time three-dimen-sional(3D)shape measurement in fringe projection profilometry(FPP).However,color crosstalk inherent in color cameras remai... Color-coded fringe patterns have emerged as a key technique for enabling real-time three-dimen-sional(3D)shape measurement in fringe projection profilometry(FPP).However,color crosstalk inherent in color cameras remains a significant factor limiting measurement accuracy.To mitigate this issue,a high-pre-cision calibration method for color crosstalk coefficients is proposed to enable effective correction in this pa-per.Specifically,a crosstalk coefficient estimator is developed based on orthogonal phase-shifted fringe pat-terns,and the theoretical relationship between the crosstalk coefficients and phase error is derived.The color orthogonal fringes are then designed to project onto a standard planar target to acquire separated R,G,and B channel patterns.Finally,a particle swarm optimization(PSO)algorithm is introduced to optimize the crosstalk-induced phase errors and calibrate the crosstalk coefficients with high precision.Experimental val-idation based on a standard dual-sphere calibration plate shows that the diameter fitting errors of the two spheres are 0.0191 mm and 0.0160 mm,respectively,and the error in the calculated center-to-center distance is as low as 0.0120 mm,which demonstrate that the proposed method can effectively enhance the measure-ment accuracy and applicability of color cameras in fringe projection technology. 展开更多
关键词 fringe projection profilometry color crosstalk coefficient phase error orthogonal fringe pattern
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Experimental investigation of contour blasting in anisotropic rocks under different lateral stress coefficients 认领 引用
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作者 PENG Si-yu LI Xi-bing +2 位作者 LIU Hui-lin WANG Zhao-wei LIANG Li-sha 《Journal of Central South University》 SCIE EI CAS CSCD 2026年第3期1242-1259,共18页
This study aims to analyze the influence of lateral stress coefficient k and anisotropy on the dynamic response and failure characteristics of deep jointed rock masses under contour blasting.Using phyllite as the test... This study aims to analyze the influence of lateral stress coefficient k and anisotropy on the dynamic response and failure characteristics of deep jointed rock masses under contour blasting.Using phyllite as the test material,local contour blasting-unloading experiments are conducted under biaxial conditions.The analysis focuses on the failure characteristics of the tunnel surrounding rock under different k and joint orientations.Results indicate that when k=1,blasting-induced fractures preferentially propagate along the joint direction.As k decreases,these fractures can deviate from the joint direction and extend toward zones of higher local stress.This tendency is particularly evident when the high-stress direction aligns with the tunnel contour,enabling fracture penetration through closely spaced contour blastholes.During the unloading,blasting-induced circumferential fractures undergo further shear failure,while radial fractures are compacted and closed.The failure of tunnel sidewalls is primarily controlled by circumferential stress concentration and anisotropic compressive strength,whereas failure at the tunnel crown is mainly governed by blasting stresses and the anisotropic tensile strength of the rock mass.This study proposes conditions for the initiation and coalescence of blasting-induced fractures,providing a theoretical basis for contour blasting and support design in anisotropic rock masses. 展开更多
关键词 laboratory experiment contour blasting excavation unloading failure characteristics lateral stress coefficient anisotropic rocks
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The Asymptotics of Fourier Coefficients Associated to Automorphic Representations over a Certain Sparse Sequence 认领 引用
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作者 Guodong HUA 《Journal of Mathematical Research with Applications》 CSCD 2026年第3期313-332,共20页
In the present paper,we investigate the asymptotics of Fourier coefficients associated to automorphic representations on a specific sparse sequence.For any fixed integer k≥2,we establish the asymptotic distribution o... In the present paper,we investigate the asymptotics of Fourier coefficients associated to automorphic representations on a specific sparse sequence.For any fixed integer k≥2,we establish the asymptotic distribution of absolute values of Fourier coefficients arising from the automorphic representations on the sequence of k-free integers.These results refine and generalize the previous work in this direction. 展开更多
关键词 automorphic representations automorphic L-functions Fourier coefficients functo-riality
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Bridging machine learning and CosMo-SAC for accurate prediction of infinite dilute activity coefficients of binary mixtures 认领 引用 被引量：1
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作者 Yuxin Qiu Guzhong Chen +3 位作者 Qian Liu Zhiwen Qi Kake Zhu Zhen Song 《ENGINEERING Chemical Engineering》 SCIE EI CAS CSCD 2026年第1期55-65,共11页
Infinite dilution activity coefficient(γ∞)is a key thermodynamic parameter in solvent design for chemical processes.Although conductor-like screening model for segment activity coefficient(COSMO-SAC)exhibits stro... Infinite dilution activity coefficient(γ∞)is a key thermodynamic parameter in solvent design for chemical processes.Although conductor-like screening model for segment activity coefficient(COSMO-SAC)exhibits strong prior predictive capabilities,its estimations are sometimes only qualitative rather than quantitative.Another limitation of COSMO-SAC arises from the reliance on time-intensive quantum chemistry calculations,which restricts its scalability for large-scale solvent screening.To overcome these issues,this study integrates COSMO-SAC with machine learning for accurate γ∞ prediction of binary mixtures.By bypassing the necessity for quantum chemistry calculations,the multi-task machine learning model could rapidly predict the surface charge density distribution(o-profiles)and molecular cavity volume(Vcosmo)of molecules and ions,while accurately distinguishing isomers.Four adjustable parameters of COSMO-SAC are optimized using more than 20000 experimental data points of γ,and residual systematic errors are further corrected with the boosting ensemble strategy to improve the model performance.The resulting hybrid model reduces the mean absolute error from 0.944 to 0.102(R2=0.969),representing an 89%improvement,while preserving the physicochemical interpretability of model.This accurate and efficient approach broadens the practical applicability of o-profiles and Vcosmo prediction,as well as γ∞ calculations based on COSMO-SAC,facilitating the high-throughput solvent screening for diverse chemical engineering applications. 展开更多
关键词 infinite dilution activity coefficient COSMO-SAC machine learning solvent design multitask learning
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Prediction of pressure coefficient distributions for basic aerodynamic configurations via point cloud characterization 认领 引用 被引量：1
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作者 Qiming Guan Weiwei Zhang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2026年第7期19-35,共17页
Data-driven approaches have shown great advantage in rapidly and accurately predicting pressure coefficient distributions,which is of crucial importance to efficient aircraft design.Nevertheless,most data-driven appro... Data-driven approaches have shown great advantage in rapidly and accurately predicting pressure coefficient distributions,which is of crucial importance to efficient aircraft design.Nevertheless,most data-driven approaches still encounter limitations in characterizing diverse aerodynamic configurations and adapting to varying grid densities,which have hindered their engineering applicability.In response to these challenges,this work adopts point clouds,a specific type of geometric data structure that is inherently suitable for uniformly characterizing diverse 2D/3D geometric shapes as the input for deep learning-based prediction of pressure coefficient distribution.By augmenting the dimensions of point cloud coordinates for local feature enhancement and utilizing the symmetric function“max pooling”to extract global features,the proposed aerodynamic model establishes the mapping between point cloud coordinates and pressure coefficients.Basic aerodynamic configurations like airfoils and wings are employed as test cases,the results demonstrate that the proposed model achieves both high accuracy and robust generalizability across variable geometries.For class-shape transformation-perturbed airfoils,the prediction error can be reduced to one-third of that of the conventional parameterization-based model.For airfoils selected in the University of Illinois Urbana-Champaign airfoil dataset,among which airfoil profiles are widely distributed,the average error of the proposed approach remains approximately 1.5%,whereas the parameterization-based model may fail.For wings,the prediction error still stays below 2.5%.Finally,the model exhibits strong robustness and generalizability across different point cloud densities.In conclusion,this work makes a breakthrough in predicting pressure coefficient distribution for variable geometric configurations,establishing the foundational framework for designing a large model capable of predicting distributed aerodynamic loads in aerospace applications. 展开更多
关键词 Data-driven Deep learning Pressure coefficient distribution prediction Point cloud Point cloud-based machine learning
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Effect of key parameters on the refueling reactivity coefficient in a pebble-bed high-temperature gas-cooled reactor 认领 引用
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作者 Zhong‑Kai Sheng Bing Xia +3 位作者 Hong‑Wei Wu Ding She Fu Li Zuo‑Yi Zhang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2026年第8期308-318,共11页
Online continuous refueling is one of the main features of a pebble-bed high-temperature gas-cooled reactor(PB-HTR).During the normal operation of a PB-HTR,positive reactivity is mainly introduced through refueling,wh... Online continuous refueling is one of the main features of a pebble-bed high-temperature gas-cooled reactor(PB-HTR).During the normal operation of a PB-HTR,positive reactivity is mainly introduced through refueling,whereas negative reactivity is introduced through depletion.Therefore,evaluating the refueling reactivity coefficient is crucial for the safe and stable operation of PB-HTRs.In this study,the perturbation theory is used to calculate the refueling reactivity coefficient,and the effect of key parameters on the refueling reactivity coefficient is examined based on the HTR-PM equilibrium core.The refueling reactivity introduced into the reactor core is driven by the gradient of the nuclide atomic density,particularly235U.The neutron flux modulates the spatial distribution of the refueling reactivity.The loading fraction of the fresh fuel directly and positively influences the refueling reactivity coefficient.This study provides comprehensive insights into the effect of these parameters on the refueling of PB-HTRs,paving the way for efficient fuel management. 展开更多
关键词 Refueling reactivity coefficient PB-HTR Perturbation theory
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A mesoscale stress-damage-seepage coupling model of hydraulic asphalt concrete incorporating the damage-dependent permeability coefficient of asphalt mortar 认领 引用
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作者 Nanxuan Qian Wei Luo +3 位作者 Bingyu Mei Desheng Yin Yixin Feng Hui Peng 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2026年第1期192-208,共17页
Hydraulic asphalt concrete(HAC)has been increasingly employed as an appropriate impervious structure in hydraulic and hydropower engineering.However,asphalt mortar,usually seen as the matrix of HAC composite,is partic... Hydraulic asphalt concrete(HAC)has been increasingly employed as an appropriate impervious structure in hydraulic and hydropower engineering.However,asphalt mortar,usually seen as the matrix of HAC composite,is particularly prone to damage under combined stress and seepage interactions,and the mesoscale investigations on the damage-seepage coupling behavior of HAC under complex stress states remain limited.This research develops a numerical three-dimensional mesoscale model composed of asphalt mortar and polyhedral aggregate to investigate the stress-damage-seepage coupling behavior in HAC.In this model,asphalt mortar yields the viscoelastic continuum damage law and aggregate obeys the Mazars’elastic-brittle damage law;simultaneously,the effective permeability coefficient of asphalt mortar is assumed to follow an exponential function of damage.The predicted deviatoric stress-strain and hydraulic gradient-seepage curves both are in good agreement with the reported experimental results,which shows the proposed model is valid and reasonable.The simulated results indicate that the damaged asphalt mortar can induce localized areas of high permeability,which in turn affects the overall impervious performance of HAC. 展开更多
关键词 Effective permeability coefficient Viscoelastic continuum damage Stress-seepage coupling
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Facile Construction of Hierarchical Polymeric Positive Temperature Coefficient Composites for Improved Reproducibility 认领 引用
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作者 Bao-Yu Wang Heng-Yu Zhao +7 位作者 Xin Ji Wei Hu Yu-Ru Duan Jian-Ze Li Zi-Hao Zhang Ying Liang Bin Fang Zhen Zhang 《Chinese Journal of Polymer Science》 SCIE EI CAS CSCD 2026年第8期2681-2690,I0017,共10页
Adopting composite matrices has great significance for improving the performance of polymeric positive temperature coefficient(PPTC)materials.However,the uncontrollable selective distribution of fillers in different m... Adopting composite matrices has great significance for improving the performance of polymeric positive temperature coefficient(PPTC)materials.However,the uncontrollable selective distribution of fillers in different matrices induced by the differences in compatibility severely limits the flexible design and regulation of conductive networks.A solution-mixing strategy based on the solubility difference of polymer matrices in different solvents was employed to flexibly fabricate hierarchical PPTC composites,achieving the precise localization of conductive fillers.In the hierarchical structure,PVDF/TiC served as the first-level PTC material,whereas the PA1010/TiC particles acted as the other-level PTC material.The PA1010/TiC particles serving as relay stations also participated in the construction of the PVDF/TiC conductive network.Benefiting from the restriction effect of the PA1010/TiC particles for the PVDF chains and TiC fillers,the negative temperature coefficient(NTC)effect was effectively suppressed,and a maximum IPTC of 8.9 was obtained.Moreover,in cyclic testing,the PVDF phase crystallized posterior to the PA1010phase,generating compression and releasing latent heat for the PA1010 phase,which synergistically reinforced the crystallization of the PA1010phase,enabling rapid reconstruction of long-range conductive networks in the entire system.Therefore,the reproducibility and Ihold of the hierarchical PPTC thermistor were significantly improved.This strategy not only breaks the bottleneck of the selective distribution of fillers in the multi-matrix of PPTC materials,but also achieves dynamic control of hierarchical conductive networks,suggesting a new pathway toward the overall improvement of the performance of PPTC thermistors. 展开更多
关键词 Polymeric positive temperature coefficient thermistor Solution mixing method Hierarchical conductive networks Reproducibility
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Adaptive implementation of multi-branch convolution with fusion coefficients based on reconfigurable array 认领 引用
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作者 Liu Dongyue Jiang Lin +2 位作者 Wang Mei Li Yuancheng Hao Juan 《High Technology Letters》 EI CAS 2026年第1期39-48,共10页
Reconfigurable array architecture has become an important hardware platform for edge-side deployment of convolutional neural networks due to their high parallelism and flexible programmability.However,traditional mult... Reconfigurable array architecture has become an important hardware platform for edge-side deployment of convolutional neural networks due to their high parallelism and flexible programmability.However,traditional multi-branch convolutional networks suffer from computational redundancy,high memory access overhead,and inefficient branch fusion.Therefore,this paper proposes an adaptive multi-branch convolutional module(AMBC)that integrates software-hardware co-optimization.During training,the learnable fusion coefficients are introduced to enable adaptive fusion of multi-scale features,while in the inference phase,the multiple branches and their normalization parameters are merged with the fusion coefficients into a single 3×3 convolutional kernel through operator fusion.On the SIREA-288 reconfigurable platform,compared with unoptimized multi-branch networks,the proposed AMBC reduces external memory accesses by 47.91%and inference latency by 47.20%,achieving a 1.90×speedup.This approach maximizes the utilization of the reconfigurable logic while minimizing both reconfiguration and data-movement overheads in edge inference. 展开更多
关键词 reconfigurable array processor structural re-parameterization model compression fusion coefficients edge-side inference acceleration hardware-software co-optimization
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Gain-Based Neural Secure Protection Control for Feedforward Nonlinear Systems With Unknown Control Coefficients and Impulsive FDI Attacks 认领 引用
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作者 Debao Fan Qingrong Liu +2 位作者 Rong Su Xianfu Zhang Wenjie Zhang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2026年第5期1068-1081,共14页
This paper proposes a gain-based neural secure protection(GBNSP)control scheme for feedforward nonlinear systems subject to unknown control coefficients and impulsive false data injection(FDI)attacks.Notably,the nonli... This paper proposes a gain-based neural secure protection(GBNSP)control scheme for feedforward nonlinear systems subject to unknown control coefficients and impulsive false data injection(FDI)attacks.Notably,the nonlinear functions of the systems are relaxed to any continuous functions and the control coefficients are permitted to be constants with both unknown sizes and signs,a scenario not covered in existing works.Furthermore,the uncertain abrupt changes in system states caused by impulsive FDI attacks inevitably exacerbate the challenges in control design.To this end,this paper integrates the neural network technique and the gain control method to propose a novel GBNSP control scheme.Specifically,the neural network technique effectively compensates for strong nonlinearities and uncertainties,while the gain control method quantifies the tolerable frequency of impulsive FDI attacks and avoids the tedious design procedures.It is shown that,under the designed GBNSP controller,all closed-loop signals remain bounded and the system states eventually converge to an adjustable neighborhood near the origin.Moreover,an enhanced GBNSP control scheme incorporates an improved gain scaling mechanism to withstand unknown external disturbances.In the end,the effectiveness and practicality of the proposed scheme are validated by a theoretical example and a practical example. 展开更多
关键词 Feedforward nonlinear systems gain scaling control impulsive FDI attacks neural secure protection control unknown control coefficients
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Neutron‑gamma density measurement method using the mass attenuation coefficient function 认领 引用
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作者 Jun‑Yan Chen Qiong Zhang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2026年第1期180-192,共13页
Although traditional gamma-gamma density(GGD)logging technology is widely utilized,its potential environmental risks have prompted the development of more environmentally friendly neutron-gamma density(NGD)logging tec... Although traditional gamma-gamma density(GGD)logging technology is widely utilized,its potential environmental risks have prompted the development of more environmentally friendly neutron-gamma density(NGD)logging technology.However,NGD measurements are influenced by both neutron and gamma radiations.In the logging environment,variations in the formation composition indicate different elemental compositions,which affect the neutron-gamma reaction cross-sections and gamma generation.Compared to traditional gamma sources such as Cs-137,these changes significantly affect the generation and transport of neutron-induced inelastic gamma rays and hinder accurate measurements.To address this,a novel method is proposed that incorporates the mass attenuation coefficient function to account for the effects of various lithologies and pore contents on gamma-ray attenuation,thereby achieving more accurate density measurements by clarifying the transport processes of inelastic gamma rays with varying energies and spatial distributions in varied logging environments.The proposed method avoids the complex correction of neutron transport and is verified through Monte Carlo simulations for its applicability across various lithologies and pore contents,demonstrating absolute density errors that are less than 0.02 g/cm3in clean formations and indicating good accuracy.This study clarifies the NGD mechanism and provides theoretical guidance for the application of NGD logging methods.Further studies will be conducted on extreme environmental conditions and tool calibration. 展开更多
关键词 Neutron-gamma density Mass attenuation coefficient Monte Carlo simulation
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Predicting permeability coefficients of earth-rock material using an improved generative adversarial network and explainable ensemble learning under small sample conditions 认领 引用
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作者 Chengyu YU Hongling YU +4 位作者 Xiaofeng QU Baoxi LIU Liangsi XU Xinyu LIU Xiangyu CHEN 《Journal of Zhejiang University-SCIENCE A》 SCIE EI CAS CSCD 2026年第3期215-230,共16页
Accurate prediction of the permeability coefficient is crucial for evaluating the compaction quality of earthworks.However,during the compaction process,on-site testing is often time-consuming and expensive,leading to... Accurate prediction of the permeability coefficient is crucial for evaluating the compaction quality of earthworks.However,during the compaction process,on-site testing is often time-consuming and expensive,leading to fewer samples,which affects prediction accuracy.Moreover,most current predictive models have limited capabilities and tend to be black-box models with poor explainability.To overcome these issues,in this study,we proposed a new method to predict the permeability coefficient of earth-rock material based on an improved generative adversarial network(GAN)and explainable osprey optimization algorithm–Huber loss–light gradient boosting machine(OOA–HL–LightGBM).Firstly,by introducing the Wasserstein distance as the loss function into the conditional generative adversarial network(CGAN),the Wasserstein conditional generative adversarial network(WCGAN)was proposed to generate high-quality data,addressing the issue of insufficient information caused by small samples.Furthermore,by incorporating material and compaction parameters as inputs,a high-accuracy permeability coefficient prediction model was developed using LightGBM with the Huber loss function and the OOA.Finally,the Shapley additive explanation(SHAP)method was introduced into OOA–HL–LightGBM to analyze the specific roles of different features within the dataset to enhance the credibility of the prediction results.The proposed method was applied to a large-scale high-core rockfill dam in southwestern China to thoroughly verify its effectiveness and superiority. 展开更多
关键词 Permeability coefficient prediction Light gradient boosting machine(LightGBM) Wasserstein conditional generative adversarial network(WCGAN) Shapley additive explanation(SHAP)
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Role of diffusion-weighted magnetic resonance imaging and apparent diffusion coefficient in subtyping renal cell carcinoma 认领 引用
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作者 Hira Lal Pinky Jowel +9 位作者 Pragati Verma Athar Shamim Raghunandan Prasad Anuradha Singh Uday P Singh Sanjoy K Sureka Farhana Siddiqui Manoj Jain Aneesh Srivastava Priyank Yadav 《World Journal of Radiology》 2026年第5期67-76,共10页
BACKGROUND Diffusion-weighted magnetic resonance imaging(DWI)has emerged as a noncontrast functional imaging technique for renal mass characterization.Its role in differentiating histopathological subtypes of renal ce... BACKGROUND Diffusion-weighted magnetic resonance imaging(DWI)has emerged as a noncontrast functional imaging technique for renal mass characterization.Its role in differentiating histopathological subtypes of renal cell carcinoma(RCC)remains an area of active investigation.AIM To evaluate the role of DWI and apparent diffusion coefficient(ADC)values in differentiating histopathological subtypes of RCC.METHODS In this prospective observational study,127 patients with histopathologically proven RCC who underwent preoperative magnetic resonance imaging(MRI)including DWI were analyzed.Diffusion-weighted imaging was performed using b values of 0 second/mm2 and 1000 seconds/mm2,and ADC maps were generated.ADC values were measured from solid tumor components and compared among RCC subtypes.Statistical analysis included subgroup comparisons and receiver operating characteristic curve analysis to assess the ability of ADC values to differentiate clear cell RCC(ccRCC)from non-ccRCC.RESULTS Of the 127 RCCs,97(76.4%)were ccRCC,24(18.9%)papillary RCC,and 6(4.7%)chromophobe RCC.The mean ADC value of ccRCC[(1.391±0.271)×10-3mm2/second]was significantly higher than that of papillary RCC[(0.876±0.293)×10-3mm2/second;P<0.001]and chromophobe RCC[(1.059±0.369)×10-3mm2/second;P=0.04].No significant difference was observed between papillary and chromophobe RCC(P=0.396).When grouped,ccRCC demonstrated a significantly higher mean ADC value compared with non-ccRCC[(1.391±0.271)×10-3mm2/second vs(0.915±0.312)×10-3mm2/second;P<0.001].Receiver operating characteristic analysis yielded an area under the curve of 0.889(95%confidence interval:0.804-0.975).An ADC threshold of 1.08×10-3mm2/second achieved 90%sensitivity and 83%specificity for identifying ccRCC.CONCLUSION DWI with quantitative ADC analysis reliably differentiates clear cell from non-ccRCC and demonstrates significant correlation with RCC subtype and tumor grade.DWI serves as a valuable adjunct to conventional MRI,particularly in patients with contraindications to contrast administration. 展开更多
关键词 Renal cell carcinoma Diffusion-weighted imaging Apparent diffusion coefficient Magnetic resonance imaging Tumor subtyping
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A variable coefficient second-degree Abel equation method for the complex Ginzburg-Landau equation with anti-cubic nonlinearity 认领 引用
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作者 Harun Biçer 《Communications in Theoretical Physics》 SCIE CAS CSCD 2026年第6期39-51,共13页
This paper introduces a novel analytical technique called the "Variable Coefficient Second Degree Generalized Abel equation Method"(VCSDGAE),designed to tackle the complex Ginzburg-Landau equation.Unlike con... This paper introduces a novel analytical technique called the "Variable Coefficient Second Degree Generalized Abel equation Method"(VCSDGAE),designed to tackle the complex Ginzburg-Landau equation.Unlike conventional methods that depend on constant coefficient ordinary differential equations(ODEs) and auxiliary ODEs,our approach employs variable coefficient ODEs within a sub-equation framework.We demonstrate the versatility of this method by successfully applying it to the complex Ginzburg-Landau equation.Through the presentation of analytical solutions,we showcase the method's effectiveness and efficiency,positioning it as a valuable resource for addressing complex nonlinear partial differential equations in fields such as fluid dynamics and wave propagation.The stability of the obtained soliton solutions is established through a linear stability analysis,confirming their robustness against small perturbations.This research not only broadens the spectrum of available analytical techniques but also contributes significantly to the advancement of solutions for various mathematical physics models. 展开更多
关键词 complex Ginzburg-Landau equation variable coefficient second degree generalized Abel equation method analytical solutions nonlinear partial differential equations stability analysis
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Apparent diffusion coefficient of kidneys with non-contrast magnetic resonance angiography for functional and anatomical assessment in renal artery stenosis 认领 引用
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作者 Hira Lal Surabhi Agarwal +7 位作者 Kaushik Ponmalai Raghunandan Prasad Dharmendra S Bhadauria Sanjay Gambhir Swagata Mandal Sandeep Kumar Priyank Yadav Pinky Jowel 《World Journal of Methodology》 2026年第1期198-210,共13页
BACKGROUND Renal artery stenosis(RAS)is a vascular disorder linked to secondary hypertension,chronic kidney disease,and renal failure due to interstitial fibrosis.Early diagnosis is crucial as RAS-induced hypertension... BACKGROUND Renal artery stenosis(RAS)is a vascular disorder linked to secondary hypertension,chronic kidney disease,and renal failure due to interstitial fibrosis.Early diagnosis is crucial as RAS-induced hypertension responds well to angioplasty.Non-invasive imaging techniques,including non-contrast magnetic resonance angiography(NC-MRA),help assess RAS without contrast-related risks.Diffusion-weighted MR imaging(DW-MRI)has emerged as a promising method for evaluating kidney function by measuring the apparent diffusion coefficient(ADC),which correlates with renal pathology.AIM To compare ADC values in hypertensive,RAS,and healthy kidneys,assess the correlation between ADC and stenosis severity,and evaluate its relationship with split glomerular filtration rate(GFR).METHODS This prospective observational study which included 86 patients with suspected RAS and twenty normal healthy controls underwent NC-MRA on a 3T-MR-Scanner followed by DW-MRI at b values of 0 and 1000 seconds/mm2 in the transverse plane.ADC maps were created using Functool.ADC values were measured in the cortex and medulla of each kidney's upper,middle,and lower pole,and the average ADC(ADCavg)for cortex and medulla calculated.In patients with RAS,degree of stenosis(DOS)was calculated on NC-MRA.The ADC of 212 kidneys was compared,and the relationship between DOS and ADC was established.In addition,split GFR was calculated in 30 kidneys using 99mTc-DTPA,and correlated with ADC value.The ADC values of kidneys with and without RAS were compared using the Student’s t-test.The correlation between ADC and stenosis severity was assessed by Spearman’s test,while the relationship between ADC and split GFR was evaluated using Pearson’s test.A P value<0.05 was considered statistically significant.RESULTS RAS was detected in 58 of 86(67.44%)hypertensive patients(81 of 172 kidneys),and the ADCavg(P=0.044)was significantly lower in RAS kidneys than in kidneys with normal arteries and essential hypertension and healthy controls.CONCLUSION DW-MRI can be a useful non-invasive technique to estimate the kidney’s functional status in RAS patients.It can be used as a complementary assessment tool with NC-MRA to triage patients in need of interventional management. 展开更多
关键词 Renal artery stenosis Diffusion weighted imaging Apparent diffusion coefficient Magnetic resonance imaging Non-contrast renal magnetic resonance angiography Hypertension
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Study on Static Three-Component Aerodynamic Force Coefficients of a Streamlined Box Girder Based on CFD 认领 引用
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作者 Shijie Guan Xu Wang Dajiang Chen 《Journal of Architectural Research and Development》 2026年第1期23-27,共5页
A systematic investigation on the static three-component aerodynamic force coefficients of a streamlined box girder cross-section is conducted using the Computational Fluid Dynamics (CFD) approach. The Reynolds-Averag... A systematic investigation on the static three-component aerodynamic force coefficients of a streamlined box girder cross-section is conducted using the Computational Fluid Dynamics (CFD) approach. The Reynolds-Averaged Navier–Stokes (RANS) equations coupled with an appropriate turbulence model are employed to establish numerical simulation models of the bridge girder under various angles of attack. The flow field structures and aerodynamic characteristics around the main girder are simulated and analyzed in detail. By comparing the variations of lift, drag, and moment responses under different angles of attack, the characteristic curves of the three-component force coefficients are obtained. Furthermore, the locations of key flow separation points, the evolution of wake vortex structures, and their influences on aerodynamic force variations are examined to elucidate the underlying flow mechanisms governing the changes in aerodynamic coefficients. The results provide theoretical insights and technical support for wind-resistant design, aerodynamic optimization of streamlined box girders, and the selection of wind tunnel test parameters. 展开更多
关键词 Streamlined box girder Computational fluid dynamics(CFD) Static aerodynamic force coefficients
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Absorption-Reflection-Transmission Power Coefficient Guiding Gradient Distribution of Magnetic MXene in Layered Composites for Electromagnetic Wave Absorption 认领 引用 被引量：11
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作者 Yang Zhou Wen Zhang +7 位作者 Dong Pan Zhaoyang Li Bing Zhou Ming Huang Liwei Mi Chuntai Liu Yuezhan Feng Changyu Shen 《Nano-Micro Letters》 SCIE EI CAS CSCD 2025年第6期466-481,共16页
The morphological distribution of absorbent in composites is equally important with absorbents for the overall electromagnetic properties,but it is often ignored.Herein,a comprehensive consideration including electrom... The morphological distribution of absorbent in composites is equally important with absorbents for the overall electromagnetic properties,but it is often ignored.Herein,a comprehensive consideration including electromagnetic component regulation,layered arrangement structure,and gradient concentration distribution was used to optimize impedance matching and enhance electromagnetic loss.On the microscale,the incorporation of magnetic Ni nanoparticles into MXene nanosheets(Ni@MXene)endows suitable intrinsic permittivity and permeability.On the macroscale,the layered arrangement of Ni@MXene increases the effective interaction area with electromagnetic waves,inducing multiple reflection/scattering effects.On this basis,according to the analysis of absorption,reflection,and transmission(A-R-T)power coefficients of layered composites,the gradient concentration distribution was constructed to realize the impedance matching at low-concentration surface layer,electromagnetic loss at middle concentration interlayer and microwave reflection at high-concentration bottom layer.Consequently,the layered gradient composite(LG5-10-15)achieves complete absorption coverage of X-band at thickness of 2.00-2.20 mm with RLmin of-68.67 dB at 9.85 GHz in 2.05 mm,which is 199.0%,12.6%,and 50.6%higher than non-layered,layered and layered descending gradient composites,respectively.Therefore,this work confirms the importance of layered gradient structure in improving absorption performance and broadens the design of high-performance microwave absorption materials. 展开更多
关键词 Magnetic MXene Layered and gradient structure Power coefficient Electromagnetic wave absorption
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