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Human-Robot Interaction-Based Model Predictive Control for Exoskeleton Robots Driven by Series Elastic Actuators 认领 引用
1
作者 Changxian Xu Keping Liu Zhongbo Sun 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2026年第2期486-488,共3页
Dear Editor,This letter presents a model predictive control(MPC)scheme for human-robot interaction(HRI)in a multi-joint exoskeleton robot(ER)driven by series elastic actuator(SEA).The proposed scheme in robot-in-charg... Dear Editor,This letter presents a model predictive control(MPC)scheme for human-robot interaction(HRI)in a multi-joint exoskeleton robot(ER)driven by series elastic actuator(SEA).The proposed scheme in robot-in-charge(RIC)mode facilitates the ER driven by SEA to provide the required assistance and support for the subject. 展开更多
关键词 human robot interaction model predictive assistance support series elastic actuator model predictive control series elastic actuator sea exoskeleton robot robot charge mode
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Finite-Time Sliding-Mode Control for Semi-Markov Systems With Delayed Impulses 认领 引用 被引量：1
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作者 Fangmin Ren Xiaoping Wang +1 位作者 Yangmin Li Zhigang Zeng 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2026年第3期740-742,共3页
Dear Editor,This letter concerns the design of sliding mode control(SMC)for semi-Markov switching systems with time-varying transmission and impulse delay.The difficulties of this problem are:1)Time-varying transmissi... Dear Editor,This letter concerns the design of sliding mode control(SMC)for semi-Markov switching systems with time-varying transmission and impulse delay.The difficulties of this problem are:1)Time-varying transmission and impulse delay bring more nonlinear dynamic characteristics and lag effects;2)Semi-Markov mode switching introduces uncertainty;3)The reachable stage and sliding stage are affected by two types of impulses in the system,which increases the complexity of theoretical derivation. 展开更多
关键词 finite time sliding mode control sliding mode control smc semi Markov systems lag effects semi markov reachable stage sliding stage theoretical derivation impulse delay time varying transmission
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System reliability analysis of jointed bedding rock slopes under seismic loading:Integrating multiple failure modes 认领 引用
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作者 ZHANG Yingbin CHEN Haiping +3 位作者 FU Junwen LI Dejian LI Hekai YU Qiangshan 《Journal of Mountain Science》 SCIE CSCD 2026年第5期2074-2087,I0007-I0010,共14页
Jointed bedding rock slopes are susceptible to multiple failure modes under seismic loading,yet conventional stability assessments relying on a single mode are insufficient and may introduce significant errors,potenti... Jointed bedding rock slopes are susceptible to multiple failure modes under seismic loading,yet conventional stability assessments relying on a single mode are insufficient and may introduce significant errors,potentially underestimating slope instability risk.This study established a novel system reliability framework,integrating four key failure modes—translational(TM),rotational(RM),upper rotationallower translational(URLTM),and upper translationallower rotational(UTLRM)—for seismic stability assessment.Utilizing Monte Carlo simulation,the framework explicitly accounted for inherent randomness and uncertainty in the strength parameters of joint surfaces and rock bridges.System reliability was evaluated using the minimum safety factor(FS)to identify the dominant failure mode.The analysis reveals that using only a single failure model can introduce maximum errors in Fs exceeding 10%;with increasing cr(cohesion)andφr(internal friction angle),the dominant failure mode changes from RM(not affected by the joint surface)to UTLRM/TM(controlled by the joint surface);as Kc(cohesion weakening coefficient)and Kφ(friction coefficient(tanφr)weakening coefficient)increase,failure is more likely atδ/β(joint surface angle/slope angle)=0.40~0.65;seismic action further increases the likelihood of joint-surface-controlled failure,increasing seismic action shifts the dominant failure mode from UTLRM to TM.These results offer direct support for the efficient determination of the dominant failure mode and sliding surface position in stability assessments of jointed bedding rock slopes. 展开更多
关键词 Jointed bedding rock slopes Multiple failure modes System reliability Monte Carlo Dominant failure mode
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Distribution patterns of three Pyrus species under climate change in China based on ensemble modeling 认领 引用
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作者 LIU Chao TIAN Luming +6 位作者 DONG Xingguang ZHANG Ying QI Dan HUO Hongliang XU Jiayu YANG Xiang CAO Yufen 《Journal of Mountain Science》 SCIE CSCD 2026年第7期3058-3070,共13页
Climate change is profoundly affecting global ecosystems and biodiversity,with fruit trees being one of the plant groups relatively sensitive to climate change.China is one of the centers of diversity for the genus Py... Climate change is profoundly affecting global ecosystems and biodiversity,with fruit trees being one of the plant groups relatively sensitive to climate change.China is one of the centers of diversity for the genus Pyrus,harboring abundant wild and cultivated germplasm resources.However,systematic assessments of the responses of Pyrus species to future climate change at the national scale in China using species distribution modelling remain limited.In this study,we compiled 153 occurrence records of Pyrus betulifolia,47 of Pyrus pyrifolia,and 117 of Pyrus ussuriensis,and integrated climatic,soil,topographic,and anthropogenic variables.A biomod2-based ensemble modelling framework was used to predict potential suitable habitats under current and future climate scenarios and to identify key environmental drivers.The results showed that temperature seasonality(Bio4)was the dominant factor influencing the distributions of P.betulifolia and P.ussuriensis,whereas precipitation of the warmest quarter(Bio18)was the primary driver of P.pyrifolia.Under current climatic conditions,highly suitable habitats accounted for 4.04%,10.93%,and 13.07%of China’s land area for the three species,respectively.Under future climate scenarios,the suitable distributions of P.betulifolia and P.pyrifolia shift northward,whereas the suitable distribution of P.ussuriensis shifts westward.Meanwhile,the suitable habitat areas of all three species are projected to expand to varying degrees. 展开更多
关键词 Ensemble model Pyrus Climate change Satisfactory habitat Species distribution mode
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A precise identification-based mode decomposition and its application in mechanical fault diagnosis 认领 引用
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作者 Bi Li Zhinong Li +1 位作者 Fengtao Wang Deqiang He 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2026年第1期88-101,共14页
Current improved Empirical Mode Decomposition(EMD)methods enhance the accurate identification of peak and valley points in mechanical signals through noise-assisted filtering techniques,thereby improving the mode deco... Current improved Empirical Mode Decomposition(EMD)methods enhance the accurate identification of peak and valley points in mechanical signals through noise-assisted filtering techniques,thereby improving the mode decomposition performance,which is of great significance in extracting fault features from mechanical signals.However,noise-assisted filtering leads to the loss of critical features in mechanical signals and introduces a large amount of residual noise into Intrinsic Mode Functions(IMFs)that obscure signal features.To address these issues,a Precise Identification-based Mode Decomposition(PIMD)method is proposed.This method directly enhances the ability of EMD to precisely identify peak and valley points by using a proposed precise identifi-cation approach,which improves mode decomposition performance and avoids the negative impacts of noise-assisted filtering,thus benefiting the extraction of more mechanical fault features.Simulation results show that the proposed PIMD method can precisely identify peak and valley points of signals with noise of different signal-tonoise ratios and perform a highly rigorous high-low frequency decomposition,significantly outperforming EMD.Finally,mechanical fault diagnostic experiments on four bearing cases and two gear cases demonstrate that,compared to four mainstream methods,the PIMD method exhibits the best mode decomposition perfor-mance and can extract more and clearer mechanical fault features. 展开更多
关键词 Mechanical fault diagnosis Precise identification-based mode decomposition Peak and valley point identification Mode decomposition performance
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Failure characteristics and the energy criterion of rock with a through-going joint under true-triaxial unloading conditions:Insights from the DEM model 认领 引用
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作者 Fei Liu Changhui Liang +2 位作者 Sijia Liu Yongjun Zhang Luo Wang 《Deep Underground Science and Engineering》 EI CAS CSCD 2026年第2期465-481,共17页
Excavation unloading damages rock masses,with preferential failure along geological defects in rock engineering,which may induce catastrophe geological hazards.It is important to study the failure of jointed rock unde... Excavation unloading damages rock masses,with preferential failure along geological defects in rock engineering,which may induce catastrophe geological hazards.It is important to study the failure of jointed rock under true-triaxial unloading conditions.3D DEM true-triaxial unloading modeling tests on rock with through-going joint considering the contributing factors,that is,the joint inclination,the initial confining pressure,and the unloading point,were conducted to study the rock mechanical properties,cracking behaviors,and failure characteristics.Six typical rock failure modes were summarized based on the development of main cracks,and the associated cracking mechanisms were studied by analysis of the ratio of tensile crack to shear crack.An energy criterion determining whether unloading-induced rock failure occurs instantaneously was proposed by comparing the accumulated elastic strain energy at the unloading point in true-triaxial unloading simulations with the limit elastic strain energy stored in rocks in biaxial compression modeling tests.Furthermore,the strength characteristics and applicability of the Mogi–Coulomb failure criterion in describing the failure of specimens with through-going joint under true-triaxial unloading conditions were studied.This study provides some new insights into true-triaxial unloading-induced failure of jointed rock,which may be valuable for revealing the mechanism of rock instabilities influenced by geological defects in deep excavations. 展开更多
关键词 cracking behavior energy criterion joint rock failure mode true-triaxial unloading modeling test
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Decomposing highly multimode fibers using a physics-driven neural network 认领 引用
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作者 Qian Zhang Yuan Sui +5 位作者 Stefan Rothe Jiali Sun Dennis Pohle Nektarios Koukourakis Guohai Situ Juergen W.Czarske 《Advanced Photonics Nexus》 CSCD 2026年第3期186-195,共10页
Multimode fibers(MMFs)play an increasing role in optical communication,ultra-thin fiber endoscopy systems,and fiber lasers.The characterization of light propagation properties through active and passive MMFs attracts ... Multimode fibers(MMFs)play an increasing role in optical communication,ultra-thin fiber endoscopy systems,and fiber lasers.The characterization of light propagation properties through active and passive MMFs attracts high interest as many linear optical phenomena fundamentally depend on the interplay among multiple spatial modes.Access to the exact modal amplitudes and phase weights via mode decomposition(MD)provides a useful means of investigating the physical effects.It facilitates technological advances in telecommunications,endoscopy,sensors,and amplifiers that utilize MMFs.We present an untrained neural network assisted by a linear physical model of the multimode waveguide that carries out computational MD.For the first time,the reconstructed amplitude distribution achieves a high correlation coefficient,either for thousands of modes in a short MMF or for tens of modes in a 1-km-long MMF.We also investigate the limitations of MD based on single-shot intensity images by evaluating the relative modal errors and the effect of image resolution on the decomposition accuracy.We demonstrate our network framework and results on both passive and active multimode photonic systems.Our approach holds great promise for applications in fiber lasers,endoscopic computational imaging,and especially in fiber-based communication,where fiber crosstalk is heavy and reference-free calibration techniques are required. 展开更多
关键词 multimode fiber mode decomposition deep learning physical information phase retrieval fiber laser
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Temperature-dependent shear behavior and constitutive model of the rock–concrete interface 认领 引用
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作者 Hongbin Chen Yujing Jiang +4 位作者 Rui Pan Bin Wang Sunhao Zhang Jinge Zhang Xianzhuang Ma 《Deep Underground Science and Engineering》 EI CAS CSCD 2026年第2期350-366,共17页
Shear tests were conducted at a shear rate of 1 mm/min and a shear displacement of 10 mm to investigate the effect of temperature on the shear behavior of the rock–concrete interface,with the aim of revealing the int... Shear tests were conducted at a shear rate of 1 mm/min and a shear displacement of 10 mm to investigate the effect of temperature on the shear behavior of the rock–concrete interface,with the aim of revealing the interaction between the surrounding rock and the lining during tunnel fires.The experimental results obtained several key findings:The mechanical properties of rock and concrete deteriorated with temperature.The mass loss rate of rock was 1.28%,with a decrease in compressive strength of 22.77%.The mass loss rate of concrete was 7.79%,with a decrease in strength of 33.27%.Concrete is more sensitive to temperature than rock under the experimental conditions.As the temperature rose,the shear fracture surface gradually shifted from within the concrete to the rock–concrete interface.Simultaneously,compaction shear displacement and peak shear displacement increased,while peak shear stress,shear stiffness and interface fracture energy decreased.In particular,the increase in compaction shear displacement and the decrease in shear stiffness were characteristic of the shear behavior of the rock–concrete interface at elevated temperatures.Subsequently,a temperature-dependent shear constitutive model of the rock–concrete interface,based on damage mechanics and statistical theory,was developed to eliminate reliance on specific experimental variables and serve as a reference for similar situations beyond the experimental conditions.This study contributes to advancing our understanding of the shear behavior of the rock–concrete interface at elevated temperatures. 展开更多
关键词 failure mode rock–concrete interface shear behavior shear constitutive model temperaturedependent
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The effect of loading mode and thermal cycling on fracture characteristics in dolomite rock 认领 引用
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作者 ALNEASAN Mahmoud ALZO'UBI Abdel Kareem 《Journal of Central South University》 SCIE EI CAS CSCD 2026年第2期925-943,共19页
The impact of repeated low-temperature thermal cycles on dolomite rock's thermomechanical behavior was examined,with a focus on how loading mode and cycle number(N)affect its properties.Dolomite samples were subje... The impact of repeated low-temperature thermal cycles on dolomite rock's thermomechanical behavior was examined,with a focus on how loading mode and cycle number(N)affect its properties.Dolomite samples were subjected to 0,50,100,and 500 thermal cycles,with fluctuations between 20 and 60℃being applied.Tensile strength,fracture toughness,elastic modulus,fracture velocity,and ultrasonic wave speeds were measured before and after the thermal cycles.An initial improvement in dolomite's performance was shown,with a peak reached around 336 cycles,followed by deterioration between 336 and 500 cycles.Specifically,increases of approximately 25.11%and 32.5%in pure modes Ⅰ and Ⅱ fracture toughness,respectively,were observed at optimal cycle numbers,before a decrease was seen at 500 cycles.Higher elastic modulus,fracture velocity,and acceleration were exhibited by mode Ⅱ specimens compared to mode I.No phase changes or chemical decomposition within the rock were indicated by X-ray diffraction and chemical analysis.The influence of mineral expansion and microcrack generation on the dolomite's structure was revealed by ultrasonic wave tests.The findings highlight how temperature fluctuations affect rock masses,which is crucial for understanding dolomite's vulnerability to damage from thermal stress and loading conditions. 展开更多
关键词 thermal cycles dolomite pure modeⅠ pure modeⅡ fracture speed elastic modulus
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Temperature-insensitive micro-displacement sensor with spindle-shaped structure single mode fiber 认领 引用
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作者 Weihua Zhang Jinlin Mu +3 位作者 Hao Wang Dong Wang Haozheng Yu Yipeng Tao 《Optoelectronics Letters》 EI 2026年第1期11-15,共5页
A temperature-insensitive micro-displacement sensor based on a spindle-shaped single mode fiber(SMF)is presented and demonstrated.The SMF is bent into a balloon-shaped SMF and burned into a spindle-shaped SMF by a fla... A temperature-insensitive micro-displacement sensor based on a spindle-shaped single mode fiber(SMF)is presented and demonstrated.The SMF is bent into a balloon-shaped SMF and burned into a spindle-shaped SMF by a flame.Due to the bending of the fiber,part of the incident light leaks from the fiber core into the fiber cladding,which excites higher order cladding modes.Therefore,modal interference occurs.The experimental results show that the maximum sensitivity of the sensors is−203 pm/µm when micro-displacement varies from 0 to 80µm.The sensors are insensitive to temperature in the range of 20–70°C.In addition,the sensors have the advantages of simple structure,low cost,small volume,high sensitivity and stability,which can be widely used in numerous high-precision industrial measurements and civil engineering structure monitoring fields. 展开更多
关键词 spindle shaped micro displacement temperature insensitive sensor temperature insensitive sensitivity single mode fiber sensor higher order cladding modesthereforemodal interference
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Research on Coordinated Operation Strategies for Wind Power Hybrid Energy Storage Systems Based on Model Predictive Control 认领 引用
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作者 Jiguang Wu Qing Zhi +4 位作者 Jin Guan Ruopeng Zhang Lixia Wu Shuhui Zhang Caifeng Wen 《Energy Engineering》 EI 2026年第7期424-444,共21页
This paper proposes a hybrid energy storage control method that coordinates the minimum output of the wind-storage system and the SOC self-recovery capability,applied to stand-alone energy storage stations.Under the p... This paper proposes a hybrid energy storage control method that coordinates the minimum output of the wind-storage system and the SOC self-recovery capability,applied to stand-alone energy storage stations.Under the premise of meeting the wind power smoothing requirements,model predictive control(MPC)is employed to rapidly regulate the SOC and output of the energy storage system during the smoothing process,thereby enhancing its sustained and stable operation capability,and decomposing the original wind power into a direct grid-connected component and a hybrid energy storage smoothing component.Subsequently,the Northern Goshawk AlgorithmImproved Complete Ensemble Empirical Mode Decomposition with Adaptive Noise(NGO-ICEEMDAN)method is employed to decompose and reconstruct the hybrid energy storage power obtained from MPC rolling optimization by determining the optimal combination of white noise amplitude weight Nstd and the number of noise additions(NA),and to allocate the reconstructed power between the supercapacitor and the battery.Finally,simulation verification is conducted using actual 10o MW wind power data from a site in Inner Mongolia.The results demonstrate that the proposed strategy can coordinate the relationship among the minimum output of the hybrid energy storage system(HESS),SOC balancing,and grid-connected power fluctuations.The NGO-ICEEMDAN method enables more precise power allocation,thereby improving the rationality and efficiency of energy management in wind power hybrid energy storage systems. 展开更多
关键词 Standalone energy storage power station hybrid energy storage system model predictive control empirical mode decomposition multi-objective optimization
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Mycorrhizal communities in Orchidaceae are likely shaped by plant trophic mode and biogeography but not phylogeny 认领 引用 被引量：1
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作者 Deyi Wang Vincent S.F.T.Merckx +1 位作者 Hans Jacquemyn Sofia I.F.Gomes 《Plant Diversity》 SCIE CAS CSCD 2026年第1期117-127,共11页
Mycorrhizal symbioses are prevalent in terrestrial ecosystems and play essential roles in plant nutrition and health.However,the relative importance of plant evolutionary history,physiology,and eco-geographical factor... Mycorrhizal symbioses are prevalent in terrestrial ecosystems and play essential roles in plant nutrition and health.However,the relative importance of plant evolutionary history,physiology,and eco-geographical factors in shaping mycorrhizal fungal community assembly remains poorly understood.Here,we investigate how plant phylogeny,trophic mode,biogeographic distribution and environmental niche collectively influence the diversity and composition of mycorrhizal fungal communities across the Orchidaceae,spanning broad phylogenetic and ecological scales.By using family-wide orchid-fungal associations and global occurrence data,our analyses showed that the variation in fungal diversity and community structure can be partially explained by orchids’trophic mode,biogeographic distribution and environmental niche,but not by their overall phylogenetic relatedness.Among trophic modes,partially mycoheterotrophic orchids exhibited the highest level of fungal diversity(the lowest level of fungal specificity)in association with a broad range of phylogenetically dispersed fungal partners.Between biogeographical regions,a significantly higher level of fungal specificity was found for orchid species distributed in Australia than those in Eurasia and Africa.Furthermore,multivariate analyses showed that a small portion of the variation in fungal community structure was significantly related to broad climate,soil and vegetation variables,indicating the existence of large-scale habitat filtering on orchid mycorrhizal communities.Altogether,our findings indicate that mycorrhizal communities in the orchid family are likely shaped by multiple,intertwined factors related to orchid ecophysiology and biogeography on a global scale. 展开更多
关键词 Orchid mycorrhiza Fungal community assembly Phylogenetic relatedness Trophic mode Biogeography
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Design,Modeling,and Experiment of a Novel Wire-Driven Robotic Fish 认领 引用
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作者 Runtong Ai Bingxiong Wang +4 位作者 Guohua Yu Yang Liu Wenbo Li Yan Meng Jincun Liu 《Journal of Bionic Engineering》 SCIE EI CSCD 2026年第2期663-683,共21页
This paper proposes and develops a novel wire-driven robotic fish.Its innovation lies in achieving reciprocating caudal fin oscillation through continuous motor rotation,with adjustable oscillation amplitude.The robot... This paper proposes and develops a novel wire-driven robotic fish.Its innovation lies in achieving reciprocating caudal fin oscillation through continuous motor rotation,with adjustable oscillation amplitude.The robotic fish can swim without frequent motor reversal and dynamically adjust the caudal fin oscillation amplitude and frequency according to different environmental requirements.First,the mechanical design and working principle of the robotic fish are described in detail.Second,a comprehensive dynamic analysis is conducted.The kinematic model of the robotic fish is established using the Newton-Euler method,and the hydrodynamic parameters in the model are determined through data-driven parameter identification methods.To verify the performance of the robotic fish and the accuracy of the dynamic model,relevant experiments and simulations were carried out,and the results were compared.Simulation results show that the robotic fish exhibits good swimming performance and reveal the validity of the dynamic model.Finally,field experiments were conducted,demonstrating that the robotic fish has good swimming stability and environmental adaptability.This study provides insights into enhancing the practical value of robotic fish in real-world applications. 展开更多
关键词 Robotic fish Wire-driven mode Dynamic modeling Field experiments
Multi-dynamic torque coordination control strategy for a power-split hybrid electric vehicle during mode shift 认领 引用
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作者 Kun Huang Weida Wang +2 位作者 Jiankang Cheng Chao Yang Changle Xiang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2026年第1期486-495,共10页
Mode shift is a special mechanism for a power-split hybrid electric vehicle(HEV)to realise electrically variable transmission,but the sudden change of equivalent inertia caused by topological configuration recombinati... Mode shift is a special mechanism for a power-split hybrid electric vehicle(HEV)to realise electrically variable transmission,but the sudden change of equivalent inertia caused by topological configuration recombination during mode shift induces a significant torque shock.Therefore,a smooth transient process,among other concerns,typically associated with this category of vehicles,is of great importance.The present research aims to introduce a novel control strategy to manage the dynamic torque of multiple power sources and therefore im-prove ride comfort.To this end,a dynamic model of the objective power-split HEV is first built.To resolve the contention between vehicle jerk and clutch friction loss,a model predictive control(MPC)combined with control allocation(CA)is then designed for the clutch-engaged phase.To reduce the torque fluctuation caused by the inertia torques of multiple power sources,a dynamic compensation control strategy(DCcs)that coordinates motorgenerator torque to compensate for the transition torque is proposed for the brake-disengaged phase.Finally,the proposed control strategy is validated by simulation and bench test,and results show great potential in reducing shift duration,torque variation,vehicle jerk and friction loss(the simulation results show decreases of 22%,39%,83%and 53%,and the experimental results show decreases of 21%,74%,77%,and 59%,re-spectively),thereby improving shift quality. 展开更多
关键词 Power-split hybrid electric vehicle Mode shift Model predictive control Control allocation Dynamic compensation control
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Experimental Validation on a Real-World Truss Structure of a Damage Localization Method Based on Mode Shape Derivatives 认领 引用
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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》 EI 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 index δ was 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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Misaligned Parallel-Chamber Soft Pneumatic Network Actuator for Multi-Mode Gripping 认领 引用
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作者 ZHANG Dong LIU Sheng +2 位作者 SHI Mengyao CAI Yu WANG Dazhong 《Journal of Shanghai Jiaotong university(Science)》 EI 2026年第1期59-70,共12页
Grasping is a fundamental way that creatures interact with their environments and is also a key field of interest in soft robotics.Pneumatic network actuators are particularly promising candidates for the soft robotic... Grasping is a fundamental way that creatures interact with their environments and is also a key field of interest in soft robotics.Pneumatic network actuators are particularly promising candidates for the soft robotics community.However,most soft pneumatic grippers based on pneumatic network actuators can only realize a single grasping mode,with poor adaptability and dexterity in grasping objects.Therefore,a new misaligned parallel-chamber soft pneumatic actuator was presented,which mainly consists of soft chambers embedded in an elastomer structure.Then,theoretical models describing the bending deformation and three-dimensional trajectory curve of the proposed actuator were developed using the segmental constant curvature assumption and incorporating the Yeoh model.In addition,finite element simulations of the bending deformation were performed and verified experimentally.Finally,three soft grippers with different gripping modes,namely,winding,enveloping,and pinching,were designed,and gripping experiments were conducted.The results show that the designed soft gripper demonstrates good adaptability and flexibility to the target object,expanding the application range of pneumatic soft grippers in the field of picking objects.The proposed soft actuator provides a potential method for the design of a multifunctional soft gripper. 展开更多
关键词 pneumatic network actuator soft gripper multiple gripping modes modular design finite element simulation Yeoh model
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Model order reduction by dominance of mode sets and optimal modal span 认领 引用
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作者 Marcelo A.Oliveira Roberto Ades Paulo C.Pellanda 《Control Theory and Technology》 EI CSCD 2026年第3期462-473,共12页
This study introduces a novel model order reduction technique grounded in modal truncation,featuring the concept of optimal modal spans.It extends traditional modal dominance analysis by evaluating not only individual... This study introduces a novel model order reduction technique grounded in modal truncation,featuring the concept of optimal modal spans.It extends traditional modal dominance analysis by evaluating not only individual modes but also the collective influence of mode sets on approximation accuracy.For a specified reduced order,the method identifies the most representative subset of modes by exhaustively analyzing all feasible combinations.The reduced model is further refined through residue optimization,enabling accurate approximations at lower dimensions.The use of optimal modal spans,combined with convex residue fitting,yields reduced-order models that consistently outperform classical truncation approaches.These theoretical gains are formally established and supported by two formulations,one continuous and one discrete,along with numerical experiments that validate the approach and illustrate its practical advantages. 展开更多
关键词 Model order reduction Dominant modes Modal truncation Modal span
The0S0fundamental mode excited by Sumatra-Andaman earthquake:Parameters assessment using the maximum likelihood method 认领 引用
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作者 Mikhail Vinogradov Vadim Milyukov 《Geodesy and Geodynamics》 EI CSCD 2026年第2期259-266,共8页
This paper presents new estimations for all parameters(amplitude,frequency,quality factor,and initial phase)of the0S0Earth fundamental mode,which was triggered by the 2004 Sumatra-Andaman earthquake with a magni... This paper presents new estimations for all parameters(amplitude,frequency,quality factor,and initial phase)of the0S0Earth fundamental mode,which was triggered by the 2004 Sumatra-Andaman earthquake with a magnitude of Mw9.1.Sixteen records from the IGETS superconducting gravimeters have been analyzed.Using the maximum likelihood method algorithm,frequency,initial phase,and amplitude estimates have been acquired with remarkable accuracy.The values of frequency(814.6568±0.0002μHz)and quality factor(5455±17)obtained in this study differ slightly from those of the PREM model,and the amplitude variations qualitatively correspond to those of the SKS12WM13model.The estimated time delay between the onset of the earthquake and the excitation of the mode(290 s)is consistent with the moment tensor analysis from the USGS National Earthquake Information Center. 展开更多
关键词 Free oscillations of the Earth Normal mode Radial mode0S0 Superconducting gravimeter Sumatra-Andaman earthquake Lateral heterogeneities Maximal likelihood method
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Competition between viscous and capillary forces triggers diversity of fluid distribution and imbibition modes 认领 引用
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作者 Jin-Xin Cao Yi-Qiang Li +5 位作者 Yu-Ling Zhang Ya-Qian Zhang Zhe-Yu Liu Qi-Hang Li Xue-Chen Tang Tao Song 《Petroleum Science》 SCIE EI CAS CSCD 2026年第2期928-938,共11页
Spontaneous imbibition is the process in which the wetting phase displaces a non-wetting phase under the action of capillary forces.However,variations in interfacial properties,imbibition directions,and fractures resu... Spontaneous imbibition is the process in which the wetting phase displaces a non-wetting phase under the action of capillary forces.However,variations in interfacial properties,imbibition directions,and fractures result in different imbibition modes,posing challenges to a comprehensive understanding of the process.In this study,micro fluidic chips representing matrix and fracture-matrix systems were designed.Imbibition agents with varied interfacial properties were selected to conduct experiments under counter-current and co-current conditions.A flow factor(γ),related to fracture geometry and imbibition direction,was defined and used together with the microscopic capillary number(Camicro)to characterize the imbibition process.Three distinct imbibition modes were observed for different Camicroandγ,clearly separated byγ-Camicro boundaries.During co-current imbibition,an unusual capillarydriven displacement process was observed,leading to fingering in the fracture-matrix model and leaving a large area of macroscale remaining oil.Smaller Camicro and fracture development will facilitate this process.In addition,various forms of microscale remaining oil,caused by bypass flow snap-off and Saffman-Taylor instability/Rayleigh-Taylor instability,were also observed across different imbibition processes.This study elucidates the imbibition mechanisms under the combined influence of capillary and viscous forces,providing deeper insights into the imbibition process in porous media. 展开更多
关键词 Microfluidics Imbibition mode Instability Remaining oil Porous media
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Evolution of diamond film growth modes under varied plasma conditions:insights from optical emission spectroscopy 认领 引用
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作者 Pengfei Qu Guangdi Zhou +2 位作者 Peng Jin Xu Han Zhanguo Wang 《Journal of Semiconductors》 EI CAS CSCD 2026年第1期91-97,共7页
The synthesis of high-quality heteroepitaxial diamond films on iridium composite substrates is a critical step toward advancing diamond for electronic and optical applications.Microwave plasma chemical vapor depositio... The synthesis of high-quality heteroepitaxial diamond films on iridium composite substrates is a critical step toward advancing diamond for electronic and optical applications.Microwave plasma chemical vapor deposition,combined with in situ optical emission spectroscopy,enables precise control over growth modes through plasma parameter tuning.In this study,we examine how methane concentration,microwave power,and gas pressure influence plasma species and,consequently,the growth modes of heteroepitaxial diamond by optical emission spectroscopy and scanning electron microscope.At low nucleation densities,increased methane concentrations promote the transition from faceted polyhedral to ballas structures,driven by elevated C2 radical concentrations in the plasma.Conversely,at higher nucleation densities,gas pressure,and substrate temperature dominate growth mode determination,leading to diverse morphologies,such as planar,polycrystalline,octahedral,and step-flow growth.These findings elucidate the interplay among plasma species,growth parameters,and growth mode,offering critical insights for optimizing growth conditions and preparing heteroepitaxial diamond films in a specific growth mode. 展开更多
关键词 heteroepitaxy diamond films growth modes MPCVD OES
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