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Influence of Dog-Bone Apex on Shape During Slab Horizontal Rolling Process
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作者 YU Hai-liang LIU Xiang-hua LI Chang-sheng WANG Guo-dong 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2007年第3期37-41,共5页
The deformation of slab with dog-bone shape during the horizontal rolling process was simulated using FEM, and the influences of apical dislocation of dog-bone on the slab spread as well as the minimum crop end loss a... The deformation of slab with dog-bone shape during the horizontal rolling process was simulated using FEM, and the influences of apical dislocation of dog-bone on the slab spread as well as the minimum crop end loss and the lost width at slab head and tail were analyzed. The results show that with the increase in the apical dislocation of dog-bone (LA), the slab spread and the minimum crop end loss at slab head and tail decrease, while the lost width at slab head and tail increases. Meanwhile, the relationships of S/LA-LA, LH/LA-LA, WH/LA-LA, L T/LA- LA, and W T/LA-LA were obtained. 展开更多
关键词 dog-bone apical dislocation horizontal rolling FEM
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Synchronized capture of 3D shape and color texture based on phase-shifting profilometry
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作者 WANG Su-zhen WU Wei +2 位作者 JI Yi-xin ZHANG Long-xiang WANG Jian-hua 《中国光学(中英文)》 北大核心 2026年第1期228-238,共11页
In recent years,the demand for synchronous acquisition of three-dimensional(3D)shape and col-or texture has surged in fields such as cultural heritage preservation and healthcare.Addressing this need,this paper propos... In recent years,the demand for synchronous acquisition of three-dimensional(3D)shape and col-or texture has surged in fields such as cultural heritage preservation and healthcare.Addressing this need,this paper proposes a novel method for simultaneous 3D shape and color texture capture.First,a linear model correlating camera exposure time with grayscale values is established.Through exposure time calibration,the projected red,green and blue(RGB)light and white-light grayscale values captured by a monochrome cam-era are aligned.Then,three sets of color fringes are projected onto the object to identify optimal pixels for 3D reconstruction.And,three pure-color patterns are projected to synthesize the color texture.Experimental res-ults show that this method effectively achieves synchronous 3D shape and color texture acquisition,offering high speed and precision,and avoids color crosstalk interference common in 3D reconstruction of colored ob-jects using a monochrome camera. 展开更多
关键词 three-dimensional shape monochrome camera RGB light projection
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Novel Statistical Shape Relation and Prediction of Personalized Female Pelvis,Pelvic Floor,and Perineal Muscle Shapes
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作者 Tan-Nhu Nguyen Trong-Pham Nguyen-Huu Tien-Tuan Dao 《Computer Modeling in Engineering & Sciences》 2026年第2期1-47,共47页
Vaginal delivery is a fascinating physiological process,but also a high-risk process.Up to 85%–90%of vaginal deliveries lead to perineal trauma,with nearly 11%of severe perineal tearing.It is a common occurrence,espe... Vaginal delivery is a fascinating physiological process,but also a high-risk process.Up to 85%–90%of vaginal deliveries lead to perineal trauma,with nearly 11%of severe perineal tearing.It is a common occurrence,especially for first-time mothers.Computational childbirth plays an essential role in the prediction and prevention of these traumas,but fast personalization of the pelvis and floor muscles is challenging due to their anatomical complexity.This study introduces a novel shape-prediction-based personalization of the pelvis and floor muscles for perineal tearing management and childbirth simulation.300 subjects were selected from public Computed Tomography(CT)databases.The pelvic bone nmjmeshes were generated using a coarse-to-fine non-rigid mesh alignment procedure.The floor muscle meshes were personalized using the bone mesh deformation information.A feature-to-pelvic structure reconstruction pipeline was proposed,incorporating various strategies.Ten-fold cross-validation helped determine the optimal reconstruction strategy,regression method,and feature sizes.The mesh-to-mesh distance metric was employed for evaluating.The statistical shape relation-based strategy,coupled with multi-output ridge regression,was the optimal approach for pelvic structure reconstruction.With a feature set ranging from 3 to 38,the mean errors were 2.672 to 1.613 mm,and 3.237 to 1.415 mm in muscle attachment regions.The best-and worst-case predictions had errors of 1.227±0.959 mm and 2.900±2.309 mm,respectively.This study provides a novel approach to achieving fast personalized childbirth modeling and simulation for perineal tearing management. 展开更多
关键词 Personalized statistical shape relation shape prediction female pelvis shape pelvic floor and perineal tissue shape
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Rapid Measurement of Elastic Modulus for Shaped Ceramic Tiles Based on Impulse Excitation Technique
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作者 SONG Yanyan FENG Zhiyuan +2 位作者 WANG Han WU Gang FAN Muxu 《China's Refractories》 2026年第1期12-16,共5页
This study addresses the challenge of directly determining the elastic modulus of complex shaped ceramic products—such as gas turbine combustor tiles—using conventional standardized methods,which are limited by spec... This study addresses the challenge of directly determining the elastic modulus of complex shaped ceramic products—such as gas turbine combustor tiles—using conventional standardized methods,which are limited by specimen geometry.A rapid,non-destructive testing method based on the impulse excitation technique(IET)and a shape factor coefficient was proposed.Three types of shaped ceramic tiles were selected.The elastic modulus of standard rectangular specimens obtained by destructive sampling was used as the reference value,and the shape factor coefficient for each tile type was calibrated by combining the mass and fundamental frequency of the whole tile.Using this coefficient,the elastic modulus of whole tiles was calculated solely from non-destructively measured mass and frequency.The results show that the deviation between the elastic modulus derived from the proposed method and that from destructive testing is less than 5%,confirming the accuracy and reliability of the approach.The method overcomes the shape restrictions inherent in traditional testing,offering a fast,non-destructive solution suitable for onsite quality assessment and process control during the production of shaped ceramic components. 展开更多
关键词 elastic modulus shape factor coefficient rapid testing shaped ceramic tiles
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Experimental Validation on a Real-World Truss Structure of a Damage Localization Method Based on Mode Shape Derivatives
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作者 Giada Faraco Andrea Vincenzo De Nunzio +1 位作者 Nicola Ivan Giannoccaro Arcangelo Messina 《Structural Durability & Health Monitoring》 2026年第2期23-38,共16页
Damage detection and localization analysis have gained increasing importance over the years,due to the growing number of catastrophic events and the associated risks that small,undetected cracks in structures may evol... Damage detection and localization analysis have gained increasing importance over the years,due to the growing number of catastrophic events and the associated risks that small,undetected cracks in structures may evolve into severe failures if not identified in time.In this context,vibration-based methods have been extensively investigated for structural damage detection.Among them,one of the most widely used approaches since its introduction is the curvature method.It has been successfully employed in numerous studies,consistently providing reliable results.However,the use of second-order or higher-order derivatives can be challenging when dealing with experimental data,as these are highly sensitive tomeasurement noise.Conversely,using the first derivative may simplify the analysis while maintaining robustness.Therefore,the present work introduces and experimentally demonstrates an extension of the curvature-based approach,focusing on the integration of the first derivative for damage localization.In particular,both methods based on the use of the second and first derivatives were applied to detect their capability in detecting and localizing the damage.This was tested on a slender truss structure,with induced damages at different locations,equal to just 1.069%of the structure volume.The results,obtained from this real-world case study,show that for certain structures,like slender ones,the use of the first derivative can achieve equal or even superior damage detection performance compared to the traditional second derivative method.Specifically,the comparison was evaluated based on the accuracy in localizing the damage with the twomethods,both froma visual and quantitative point of view,since a deviation indexδwas also introduced. 展开更多
关键词 Damage localization mode shapes mode shape derivatives curvature method structural health monitoring
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Shape polarization and coexistence of high-K three-quasiparticle states in odd-mass N=106 isotones
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作者 Run-Yan Dong Chang-Feng Jiao 《Nuclear Science and Techniques》 2026年第5期315-325,共11页
Three-quasiparticle K-isomeric states in odd-mass N=106 isotones within the A~180 mass region were systematically investigated using configuration-constrained potential energy surface calculations.The calculations suc... Three-quasiparticle K-isomeric states in odd-mass N=106 isotones within the A~180 mass region were systematically investigated using configuration-constrained potential energy surface calculations.The calculations succes sfully reproduced the excitation energies and deformations of the known high-K isomers in nuclei from 175Tm to 181Re.For the nuclei closer to the Z=82 shell closure(^(183)Ir,^(185)Au,and^(187)Tl),predictions of the configurations of the observed and yet-to-be-observed isomers are provided.The results reveal strong shape polarization,where the three-quasiparticle states are driven to larger deformations compared to the often shape-soft or spherical ground states.A particularly rich spectrum of shape coexistence is predicted in^(187)Tl,where several high-K three-quasiparticle configurations with distinct prolate,oblate,and triaxial shapes are found to coexist at similar excitation energies.Notably,the oblate-deformed K^(π)=29/2^(+)configuration at E_(x)=1839 keV was proposed to be responsible for a long-lived isomer.This study provides a comprehensive picture of shape evolution and coexistence in high-K multi-quasiparticle states,offering valuable insights for future experimental studies. 展开更多
关键词 shape polarization shape coexistence High-K isomeric state Con-guration-constrained potential energy surface
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Statistical Inference for Software Reliability Constrained by the Shape of the Mean Value Function
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作者 CHEN Kangan LIU Jian +1 位作者 HU Qingpei XIE Min 《Journal of Systems Science & Complexity》 2026年第1期334-362,共29页
While parametric Software Reliability Growth Models(SRGMs)serve as a cornerstone in software reliability assessment,their reliance on known fault-detection time distributions often presents a significant limitation in... While parametric Software Reliability Growth Models(SRGMs)serve as a cornerstone in software reliability assessment,their reliance on known fault-detection time distributions often presents a significant limitation in practical software testing.In this study,the authors develop a novel shaperestricted spline estimator for quantifying software reliability.Compared with parametric SRGMs,the proposed estimator not only shares a key characteristic with parametric SRGMs,but also obviates the need for specifying fault-detection time distributions.More importantly,it effectively utilizes the critical shape information of the mean value function(MVF)of fault-detection process,a detail seldom considered in prior work.Moreover,the authors investigate the predictive performance of the proposed methods by employing the so-called one-step look-ahead prediction method.Furthermore,the authors show that under certain conditions,the shape-restricted spline estimator will attain the point-wise convergence rate O_P(n~(-3/7)).In numerical experiment,the authors show that spline estimators under restriction demonstrate competitive performance compared to parametric and certain non-parametric models. 展开更多
关键词 Penalize regression spline shape restriction software reliability
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Rock-breaking experiments and simulations of shaped cutters in hard rock formations
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作者 Yang Guan Qingyou Liu +1 位作者 Tao Huang Zhengtong Mou 《Natural Gas Industry B》 2026年第1期93-110,共18页
To address the challenges of rapid bit failure and high drilling costs associated with hard limestone in Sichuan Basin of China,we conducted rock-breaking experiments and simulations of shaped(cylindrical,ridge,and ch... To address the challenges of rapid bit failure and high drilling costs associated with hard limestone in Sichuan Basin of China,we conducted rock-breaking experiments and simulations of shaped(cylindrical,ridge,and chopper)cutters.Rock mechanics,drillability,and acoustic emission indentation tests revealed the drilling resistance characteristics of the limestone:average uniaxial compressive strength of 202.472 MPa,tensile strength of 7.092 MPa,and drillability of 7.866.We evaluated the performance differences between the shaped cutters before introducing an efficient and innovative finite-discrete-infinite element method(FDIEM)to establish an interaction model between the shaped cutters and limestone.The simulation results indicated the following:(1)The shaped cutters demonstrated superior rock-breaking performance compared to the traditional cylindrical cutter.(2)Compared with the cylindrical cutter,the ridge cutter yielded the lowest peak indentation force and mechanical specific energy,with reductions of 8.71%and 33.83%,respectively.This confirmed that the ridge cutter had the optimal tooth profile for the target formation.Its rock-breaking mechanism relied on the convex edges to induce localized high stress in the rock,which enabled efficient rock fragmentation via a plowing mode while mitigating frictional resistance from cuttings.(3)The novel chopper cutter with its secondary step surface exerted a buffering effect on the cuttings,thereby achieving high cutting stability.This study provides theoretical and technical support for the design of personalized drill bits and the acceleration of the rate of penetration(ROP)in deep hard rock formations. 展开更多
关键词 Hard limestone shaped cutter FDIEM Rock-breaking mechanism ROP acceleration
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SNMR with short pulses:Optimizing the kernel calculation by considering the influence of pulse shape and phase
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作者 Tobias Splith Thomas Hiller +1 位作者 Stephan Costabel Mike Müller-Petke 《Magnetic Resonance Letters》 2026年第1期43-52,共10页
In the past few years,efforts have been made to extend the sensitivity of surface nuclear magnetic resonance(SNMR)to short relaxation times,typical for strongly bound water,which,for example,occurs in partially satura... In the past few years,efforts have been made to extend the sensitivity of surface nuclear magnetic resonance(SNMR)to short relaxation times,typical for strongly bound water,which,for example,occurs in partially saturated soils.The two limiting factors for the sensitivity are the dead time after the excitation pulse and the duration of the pulse itself.To enable short pulses,while also achieving proper depths of investigation,high pulse amplitudes are needed.This makes it necessary to consider the Bloch-Siegert effect,i.e.the counter-rotating component and the parallel component of the excitation field have significant influence on the excitation.If an untuned transmitter circuit is used,the pulse shape will also be non-sinusoidal.In this paper,we demonstrate that this influences SNMR measurements with short pulses in two ways:On one hand,the pulse shape influences the phase of the fundamental frequency oscillation.On the other,at very high pulse amplitudes,other frequency components of the excitation field start to influence the excitation.The behavior of the macroscopic magnetizations in the subsurface during the pulse is simulated by solving the Bloch equations,using the pulse shape as an input.Since these calculations are computational expensive,we propose a lookup scheme that allows a time efficient modeling of the obtained SNMR data. 展开更多
关键词 Surface NMR Pulse shape Numerical modeling Bloch-Siegert effect
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ES-YOLO:Edge and Shape Fusion-Based YOLO for Tra.c Sign Detection
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作者 Weiguo Pan Songjie Du +2 位作者 Bingxin Xu Bin Zhang Hongzhe Liu 《Computers, Materials & Continua》 2026年第4期2127-2145,共19页
Traffic sign detection is a critical component of driving systems.Single-stage network-based traffic sign detection algorithms,renowned for their fast detection speeds and high accuracy,have become the dominant approa... Traffic sign detection is a critical component of driving systems.Single-stage network-based traffic sign detection algorithms,renowned for their fast detection speeds and high accuracy,have become the dominant approach in current practices.However,in complex and dynamic traffic scenes,particularly with smaller traffic sign objects,challenges such as missed and false detections can lead to reduced overall detection accuracy.To address this issue,this paper proposes a detection algorithm that integrates edge and shape information.Recognizing that traffic signs have specific shapes and distinct edge contours,this paper introduces an edge feature extraction branch within the backbone network,enabling adaptive fusion with features of the same hierarchical level.Additionally,a shape prior convolution module is designed to replaces the first two convolutional modules of the backbone network,aimed at enhancing the model's perception ability for specific shape objects and reducing its sensitivity to background noise.The algorithm was evaluated on the CCTSDB and TT100k datasets,and compared to YOLOv8s,the mAP50 values increased by 3.0%and 10.4%,respectively,demonstrating the effectiveness of the proposed method in improving the accuracy of traffic sign detection. 展开更多
关键词 Traffic sign edge information shape prior feature fusion object detection
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Lignin-derived High-performance Near-infrared Light-responsive Shape Memory Polyurethanes for Biomedical Applications
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作者 Su-Yang Dai Jia-Yue Li +5 位作者 Ling-Chen Mao Dan-Hua Zhou Yu Zhang Zhi-Hua Gana Zhen-Bo Ning Yun-Feng Lu 《Chinese Journal of Polymer Science》 2026年第4期1090-1101,I0016,共13页
Near-infrared(NIR)light-responsive shape memory polymers(SMPs)show great promise for biomedical applications,but conventional photothermal agents suffer from high cost,complex preparation,or poor biocompatibility,whil... Near-infrared(NIR)light-responsive shape memory polymers(SMPs)show great promise for biomedical applications,but conventional photothermal agents suffer from high cost,complex preparation,or poor biocompatibility,while lignin-based alternatives exhibit insufficient photothermal conversion efficiency.Herein,we developed a novel strategy to enhance photothermal performance of lignin through sequential demethylation modification and Fe^(3+)complexation for constructing NIR light responsive SMPs.Dealkaline lignin(DL)was first demethylated using iodocyclohexane to produce demethylated lignin(DDL)with increased catechol content,which was then incorporated into polycaprolactone-based polyurethane synthesis followed by Fe^(3+)complexation.Results showed that DDL-Fe^(3+)complexes have significantly enhanced photothermal conversion performance,and the resulting PU-DDL+Fe^(3+)polyurethane with 0.5 wt%DDL content demonstrated a temperature increases of 39.8℃under 0.33 W·cm-2808 nm NIR irradiation.This excellent photothermal performance enables the shape-fixed PU-DDL+Fe^(3+)polyurethane to rapidly recover to its initial shape under NIR light irradiation.Additionally,PU-DDL+Fe^(3+)polyurethane exhibits good mechanical properties and biocompatibility,demonstrating significant biomedical application potential. 展开更多
关键词 LIGNIN POLYURETHANE shape memory polymers NIR light responsive POLYCAPROLACTONE
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The effects of compressibility and target strength on shaped charge jet penetration
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作者 Qiangqiang Xiao Zhengxiang Huang +2 位作者 Xudong Zu Xin Jia Bin Ma 《Defence Technology(防务技术)》 2026年第2期244-253,共10页
The penetration of shaped charge jets into targets at high velocities is significantly influenced by the compressibility effect,while at low velocities,the strength effect becomes predominant.In the latter regime,mate... The penetration of shaped charge jets into targets at high velocities is significantly influenced by the compressibility effect,while at low velocities,the strength effect becomes predominant.In the latter regime,material strength dictates the resistance to plastic deformation and flow,a contrast to the shockwave-dominated interactions where compressibility is key.This paper presents a self-consistent compressible penetration theory that considers both the axial penetration and radial crater growth of shaped charge jets into targets.An integrated approach where the axial and radial dynamics are coupled has been proposed,influencing each other through shared physical principles rather than being treated as separate,empirically linked phenomena.The presented theory is rooted in the compressible Bernoulli equation and the linear Rankine-Hugoniot relation.These foundational equations are employed to accurately model the high-pressure shock state and subsequent material flow at the jet-target interface,providing a robust physical basis for the penetration model.Notably,it considers the target material's compressibility,which elevates the pressure at the jet-target interface beyond that observed with incompressible materials.This pressure increase is directly proportional to the target's degree of compressibility.As such,this model of compressible penetration reorients the analytical approach:rather than merely estimating penetration resistance,it determines this value from the target material's specific compressibility and yield strength.This shift from empirical correlations to a physics-based derivation of penetration resistance enhances the model's predictive power,particularly for novel target materials or engagement conditions outside established experimental datasets.This investigation establishes a quantitative link between the material's yield strength and its penetration resistance.The accuracy of this penetration resistance value is paramount,as it significantly influences the predicted crater diameter;indeed,the crater diameter's sensitivity to this resistance underscores the necessity for its precise determination.Ultimately,by integrating the yield strength of the target material,this framework enables the prediction of both the penetration depth and the resultant crater diameter from a shaped charge jet.The theory's validation involved two experimental sets:the first focused on shaped charge jet penetration into 45#steel at varied stand-offs,while the second utilized targets of high-to ultrahigh-strength steel-fiber reactive powder concrete(RPC)with differing strength characteristics.These experimental campaigns were specifically chosen to test the theory against both ductile metallic alloys,where plastic flow is significant,and advanced quasi-brittle cementitious composites,presenting a broad spectrum of material responses and penetration challenges.Resulting hole profiles derived from theoretical calculations demonstrated a strong correspondence with empirical measurements for both material types. 展开更多
关键词 shaped charge jet Penetration efficiency Compressibility influence Strength impact
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Aerodynamic shape optimization of hypersonic aircraft using data-driven generative nonlinear parameterization
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作者 Yan CHEN Jichao LI Jinsheng CAI 《Chinese Journal of Aeronautics》 2026年第3期64-76,共13页
Aerodynamic shape optimization of hypersonic vehicles is critically important yet profoundly challenging.The difficulties arise from the need to manage multiple competing objectives,complex three-dimensional geometrie... Aerodynamic shape optimization of hypersonic vehicles is critically important yet profoundly challenging.The difficulties arise from the need to manage multiple competing objectives,complex three-dimensional geometries,and the extreme computational cost of high-fidelity aerodynamic simulations across subsonic,transonic,and hypersonic regimes.Despite recent advances,an effective global optimization strategy for hypersonic aircraft design remains limited,largely hindered by the curse of dimensionality.To remove this barrier,we propose a data-driven generative nonlinear shape parameterization framework for efficient aerodynamic design of hypersonic aircraft.This framework begins by constructing diverse hypersonic aircraft shapes that cover the feasible sub-domains of a high-dimensional design space.A linear dimension reduction method is used to transform the high-dimensional point-cloud database to a low-dimensional modal space.Subsequently,a nonlinear generative model is trained to learn the statistical distribution feature of the linear mode coefficients.The resulting generative latent space provides an efficient,lowdimensional,and expressive parameterization of aerodynamic shapes.The proposed method is validated in both single-point and multi-point optimization of hypersonic aircraft,demonstrating superior efficiency and effectiveness compared with conventional parameterization approaches.This study presents an efficient roadmap for aerodynamic shape parameterization and global optimization of next-generation aircraft. 展开更多
关键词 Aerodynamic shape optimization Deep-learning Dimension reduction Generative parameterization Hypersonic aircraft design
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Influence of interface shape on microstructure and mechanical properties of Mg/Al composite plates fabricated by hot-pressing
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作者 Shi-jun TAN Bo SONG +6 位作者 Hao-hua XU Ting-ting LIU Jia SHE Sheng-feng GUO Xian-hua CHEN Kai-hong ZHENG Fu-sheng PAN 《Transactions of Nonferrous Metals Society of China》 2026年第1期124-143,共20页
A new method was proposed for preparing AZ31/1060 composite plates with a corrugated interface,which involved cold-pressing a corrugated surface on the Al plate and then hot-pressing the assembled Mg/Al plate.The resu... A new method was proposed for preparing AZ31/1060 composite plates with a corrugated interface,which involved cold-pressing a corrugated surface on the Al plate and then hot-pressing the assembled Mg/Al plate.The results show that cold-pressing produces intense plastic deformation near the corrugated surface of the Al plate,which promotes dynamic recrystallization of the Al substrate near the interface during the subsequent hot-pressing.In addition,the initial corrugation on the surface of the Al plate also changes the local stress state near the interface during hot pressing,which has a large effect on the texture components of the substrates near the corrugated interface.The construction of the corrugated interface can greatly enhance the shear strength by 2−4 times due to the increased contact area and the strong“mechanical gearing”effect.Moreover,the mechanical properties are largely depended on the orientation relationship between corrugated direction and loading direction. 展开更多
关键词 Mg/Al composite plate interface shape MICROSTRUCTURE mechanical properties TEXTURE
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Effects of Temperature,Loading Frequency,Stress Amplitude,and Stress Ratio on the Low-Cycle Fatigue Behavior of FeMnSiCrNi Shape Memory Alloys
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作者 Bo Xu Beihai Huang +4 位作者 Sen Tang Xiang Xu Huabei Peng Chong Wang Qingyuan Wang 《Acta Mechanica Solida Sinica》 2026年第2期133-151,共19页
FeMnSi-based shape memory alloys(SMAs)have great applied potential to large-scale structures in civil engineering,especially as an aseismic structural material.Low-cycle fatigue performance is one of the most importan... FeMnSi-based shape memory alloys(SMAs)have great applied potential to large-scale structures in civil engineering,especially as an aseismic structural material.Low-cycle fatigue performance is one of the most important properties of FeMnSi-based SMA aseismic materials.However,the low-cycle fatigue behavior of such SMAs,especially the stress-controlled low-cycle fatigue behavior(with ratchetting effect),has not been clearly understood.In this work,the low-cycle fatigue behavior of the FeMnSiCrNi SMAs subjected to stress-controlled cyclic tension–compression loads is investigated,and the effects of temperature,loading frequency,stress amplitude,and stress ratio are addressed.By analyzing the cyclic stress–strain response,fatigue fracture surface morphology,dissipation energy,ratchetting strain,and equivalent damping ratio,the mechanisms behind the temperature-,loading frequency-,stress amplitude-,and stress ratio-dependent low-cycle fatigue behavior are discussed.The results show that the plasticity,martensitic transformation,and/or the ratchetting strain caused by their tension–compression asymmetry are the decisive factors affecting the low-cycle fatigue behavior of FeMnSiCrNi SMAs. 展开更多
关键词 FeMnSiCrNi shape memory alloy Low-cycle fatigue behavior TEMPERATURE Loading frequency Stress amplitude Stress ratio
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Au shape-controlled growth of Ga,GaAs and Ga/GaAs nanowires
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作者 Hang Wang Ying Wang +4 位作者 Zaixing Yang Qi Zhang Ning Han Shigeo Maruyama Rong Xiang 《International Journal of Minerals,Metallurgy and Materials》 2026年第3期990-998,共9页
Controllable synthesis of one-dimensional nanowires(NWs)is crucial for their large-scale applications,but it usually requires complicated catalyst designs with multiple compositions and careful tuning of synthesis par... Controllable synthesis of one-dimensional nanowires(NWs)is crucial for their large-scale applications,but it usually requires complicated catalyst designs with multiple compositions and careful tuning of synthesis parameters.In this study,we performed a systematic investigation into the impact of the shape of Au particles on the geometry and composition of the obtained NWs.We discovered that octahedral,dodecahedral,and cubic Au particles selectively catalyze the growth of Ga,GaAs,and Ga/GaAs heterojunction NWs,respectively.The mechanism stems from the difference in the solubility of Ga in Au catalysts with distinct shapes(i.e.,curvatures)due to the Gibbs-Thomson(G-T)effect:Au octahedrons(7.42 nm),featuring smaller curvature radii,enhance the solubility of Ga precursors,enabling efficient diffusion and faster growth of Ga NWs;Au dodecahedrons(11.22 nm)with larger curvature radii exhibit moderate Ga solubility,favoring the growth of GaAs NWs;Au cubes(10.51 nm)with intermediate Ga solubility,yield Ga/GaAs heterojunction NWs.Finally,we fabricated NW field effect transistors(FETs)and revealed that the Ga NWs exhibited promising electrical characteristics with a resistivity of 2.54×10^(−4)Ω·m,and GaAs NWs showed p-type characteristics.All these results illustrate the promising potential for tuning the geometry and composition of NWs by a single parameter,i.e.,merely changing the shape of a single Au particle. 展开更多
关键词 gold shape gallium nanowires gallium arsenide nanowires gallium/gallium arsenide heterojunction nanowires electricalcharacteristics
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Erratum:Bone Regeneration Eff cacy and Applicability of Defect-Fitting 4D Scaffolds Based on Shape Conformity in Three-dimensional Curved Bone Defects
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作者 Min-Soo Ghim Se-Jin Jang +3 位作者 Eun-Yong Choi Meiling Quan Young-Yul Kim Young-Sam Cho 《Journal of Bionic Engineering》 2026年第1期550-550,共1页
The original online version of this article was revised:The layout update for Article 758 has impacted the page range in the published issue,but did not affect the scholarly content.To ensure consistency with the orig... The original online version of this article was revised:The layout update for Article 758 has impacted the page range in the published issue,but did not affect the scholarly content.To ensure consistency with the originally assigned pages(2595-2614),we will need to publish an erratum to correct the article and restore the original page range.The original article has been corrected. 展开更多
关键词 defect fitting D scaffolds layout update shape conformity three dimensional curved bone defects bone regeneration
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4D printing of reprocessable thiocyanate covalent adaptable networks with reconfigurable shape memory ability
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作者 Ting Xu Kexiang Chen +7 位作者 Zhiyuan He Chuanzhen Zhang Xiaoyu Li Ziyan Zhang Wenbo Fan Zhishen Ge Chenhui Cui Yanfeng Zhang 《Chinese Chemical Letters》 2026年第2期505-511,共7页
Shape memory polymers used in 4D printing only had one permanent shape after molding,which limited their applications in requiring multiple reconstructions and multifunctional shapes.Furthermore,the inherent stability... Shape memory polymers used in 4D printing only had one permanent shape after molding,which limited their applications in requiring multiple reconstructions and multifunctional shapes.Furthermore,the inherent stability of the triazine ring structure within cyanate ester(CE)crosslinked networks after molding posed significant challenges for both recycling,repairing,and degradation of resin.To address these obstacles,dynamic thiocyanate ester(TCE)bonds and photocurable group were incorporated into CE,obtaining the recyclable and 3D printable CE covalent adaptable networks(CANs),denoted as PTCE1.5.This material exhibits a Young's modulus of 810 MPa and a tensile strength of 50.8 MPa.Notably,damaged printed PTCE1.5 objects can be readily repaired through reprinting and interface rejoining by thermal treatment.Leveraging the solid-state plasticity,PTCE1.5 also demonstrated attractive shape memory ability and permanent shape reconfigurability,enabling its reconfigurable 4D printing.The printed PTCE1.5 hinges and a main body were assembled into a deployable and retractable satellite model,validating its potential application as a controllable component in the aerospace field.Moreover,printed PTCE1.5 can be fully degraded into thiol-modified intermediate products.Overall,this material not only enriches the application range of CE resin,but also provides a reliable approach to addressing environmental issue. 展开更多
关键词 4D Printing Dynamic thiocyanate ester bonds Covalent adaptable networks Cyanate ester resin shape memory
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Neural boundary shape functions in physics-informed neural networks for discontinuous and high-frequency problems
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作者 P.T.NGUYEN K.A.LUONG J.H.LEE 《Applied Mathematics and Mechanics(English Edition)》 2026年第2期423-442,共20页
Physics-informed neural networks(PINNs)have been shown as powerful tools for solving partial differential equations(PDEs)by embedding physical laws into the network training.Despite their remarkable results,complicate... Physics-informed neural networks(PINNs)have been shown as powerful tools for solving partial differential equations(PDEs)by embedding physical laws into the network training.Despite their remarkable results,complicated problems such as irregular boundary conditions(BCs)and discontinuous or high-frequency behaviors remain persistent challenges for PINNs.For these reasons,we propose a novel two-phase framework,where a neural network is first trained to represent shape functions that can capture the irregularity of BCs in the first phase,and then these neural network-based shape functions are used to construct boundary shape functions(BSFs)that exactly satisfy both essential and natural BCs in PINNs in the second phase.This scheme is integrated into both the strong-form and energy PINN approaches,thereby improving the quality of solution prediction in the cases of irregular BCs.In addition,this study examines the benefits and limitations of these approaches in handling discontinuous and high-frequency problems.Overall,our method offers a unified and flexible solution framework that addresses key limitations of existing PINN methods with higher accuracy and stability for general PDE problems in solid mechanics. 展开更多
关键词 physics-informed neural network(PINN) boundary shape function(BSF) strong-form approach energy approach DISCONTINUITY high-frequency problem
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Laser-induced in situ reprogramming of magnetic shape memory composites for adaptive devices
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作者 Qianqian Zhang Rui Li +5 位作者 Yuan Tao Yiyu Chen Yanlei Hu Dong Wu Jiaru Chu Jiawen Li 《International Journal of Extreme Manufacturing》 2026年第1期767-779,共13页
Programmable/reprogrammable magneto-responsive composites(MRCs)are highly desirable for applications in soft robotics,morphable actuators,and biomedical devices due to their capabilities of undergoing reversible,compl... Programmable/reprogrammable magneto-responsive composites(MRCs)are highly desirable for applications in soft robotics,morphable actuators,and biomedical devices due to their capabilities of undergoing reversible,complex,untethered,and rapid deformations.However,current MRC-based devices primarily rely on soft matrices,which revert to their original shapes and cease functioning when external magnetic fields are removed.Moreover,their magnetization programming,deformations,and functioning need to alternate between encoding and actuation platforms,limiting the adaptability and efficiency.Here,we present a reprogrammable magnetic shape-memory composite(RM-SMC)integrating a shape-memory polymer(SMP)skeleton with phase-transition magnetic microcapsules.High-intensity laser melts microcapsules for magnetic realignment under programmed fields,while low-intensity laser softens SMP for structural reconfiguration without compromising integrity.This dual-laser strategy facilitates in situ magnetization programming,shape morphing,and function execution within a single material system.Our innovative approach enables unique applications,including omnidirectional multi-degree-of-freedom actuators that can activate light switches,solar trackers that optimize energy capture,and adaptive impellers that modulate fluid pumping.By eliminating platform alternation and enabling shape/function retention post-actuation,the RM-SMC platform overcomes critical limitations in conventional MRCs,establishing a paradigm for multifunctional devices requiring persistent configuration control and field-independent operation. 展开更多
关键词 magneto-responsive composites shape memory polymer in situ programming and deformation omnidirectional multi-degree of freedom actuator adjustable fluid pumping
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