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Composite anti-disturbance predictive control of unmanned systems with time-delay using multi-dimensional Taylor network 被引量:1
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作者 Chenlong LI Wenshuo LI Zejun ZHANG 《Chinese Journal of Aeronautics》 2025年第7期589-600,共12页
A composite anti-disturbance predictive control strategy employing a Multi-dimensional Taylor Network(MTN)is presented for unmanned systems subject to time-delay and multi-source disturbances.First,the multi-source di... A composite anti-disturbance predictive control strategy employing a Multi-dimensional Taylor Network(MTN)is presented for unmanned systems subject to time-delay and multi-source disturbances.First,the multi-source disturbances are addressed according to their specific characteristics as follows:(A)an MTN data-driven model,which is used for uncertainty description,is designed accompanied with the mechanism model to represent the unmanned systems;(B)an adaptive MTN filter is used to remove the influence of the internal disturbance;(C)an MTN disturbance observer is constructed to estimate and compensate for the influence of the external disturbance;(D)the Extended Kalman Filter(EKF)algorithm is utilized as the learning mechanism for MTNs.Second,to address the time-delay effect,a recursiveτstep-ahead MTN predictive model is designed utilizing recursive technology,aiming to mitigate the impact of time-delay,and the EKF algorithm is employed as its learning mechanism.Then,the MTN predictive control law is designed based on the quadratic performance index.By implementing the proposed composite controller to unmanned systems,simultaneous feedforward compensation and feedback suppression to the multi-source disturbances are conducted.Finally,the convergence of the MTN and the stability of the closed-loop system are established utilizing the Lyapunov theorem.Two exemplary applications of unmanned systems involving unmanned vehicle and rigid spacecraft are presented to validate the effectiveness of the proposed approach. 展开更多
关键词 multi-dimensional Taylor network Composite anti-disturbance Predictive control Unmanned systems Multi-source disturbances TIME-DELAY
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Finding Main Causes of Elevator Accidents via Multi-Dimensional Association Rule in Edge Computing Environment 被引量:2
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作者 Hongman Wang Mengqi Zeng +1 位作者 Zijie Xiong Fangchun Yang 《China Communications》 SCIE CSCD 2017年第11期39-47,共9页
In order to discover the main causes of elevator group accidents in edge computing environment, a multi-dimensional data model of elevator accident data is established by using data cube technology, proposing and impl... In order to discover the main causes of elevator group accidents in edge computing environment, a multi-dimensional data model of elevator accident data is established by using data cube technology, proposing and implementing a method by combining classical Apriori algorithm with the model, digging out frequent items of elevator accident data to explore the main reasons for the occurrence of elevator accidents. In addition, a collaborative edge model of elevator accidents is set to achieve data sharing, making it possible to check the detail of each cause to confirm the causes of elevator accidents. Lastly the association rules are applied to find the law of elevator Accidents. 展开更多
关键词 elevator group accidents APRIORI multi-dimensional association rules data cube edge computing
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Retraced Multi-dimensional Chinese Logic System behind Chinese Medicine
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作者 Edwin C.L.Yu 《Chinese Medicine and Culture》 2025年第1期1-12,共12页
The ancient tacit knowledge behind the logic system permeated the culture and promoted numerous impactful inventions throughout the history. Traditional Chinese medicine with its effectiveness should also have stemmed... The ancient tacit knowledge behind the logic system permeated the culture and promoted numerous impactful inventions throughout the history. Traditional Chinese medicine with its effectiveness should also have stemmed out from such logic system. This article aims to rearticulate the underlying lucid multi-dimensional logic system, which faded in obscurity only because of time-out loss of the mid-right concept. Retracing this past tacit but important concept could uncover a multi-dimensional system over a point relating to all matters while capturing the central core of the matter. The seemingly unmanageable multidimensional logic was strengthened by verification processes which affirmed its further extensions, and made up the language of the people, the concepts of yin-yang(阴阳), and the development of extensions of Ba Gua(八卦) derivatives, which furthered the interpretation of the space-time properties and Chinese medicine. 展开更多
关键词 multi-dimensional logic system Traditional Chinese medicine YIN-YANG
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Effective stress dissipation by multi-dimensional architecture engineering for ultrafast and ultralong sodium storage
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作者 Man Zhang Jing Zhu +7 位作者 Qianqian Li Fenghua Zheng Sijiang Hu Youguo Huang Hongqiang Wang Xing Ou Qichang Pan Qingyu Li 《Journal of Energy Chemistry》 2025年第2期619-629,I0013,共12页
Stress accumulation is a key factor leading to sodium storage performance deterioration for NiSe_(2)-based anodes.Therefore,inhibiting the concentrated local stress during the sodiataion/desodiation process is crucial... Stress accumulation is a key factor leading to sodium storage performance deterioration for NiSe_(2)-based anodes.Therefore,inhibiting the concentrated local stress during the sodiataion/desodiation process is crucial for acquiring stable NiSe2-based materials for sodium-ion batteries(SIBs),Herein,a stress dissipation strategy driven by architecture engineering is proposed,which can achieve ultrafast and ultralong sodium storage properties.Different from the conventional sphere-like or rod-like architecture,the three-dimensional(3D)flower-like NiSe_(2)@C composite is delicately designed and assembled with onedimensional nanorods and carbon framework.More importantly,the fundamental mechanism of improved structure stability is unveiled by simulations and experimental results simultaneously.It demonstrates that this designed multidimensional flower-like architecture with dispersed nanorods can balance the structural mismatch,avoid concentrated local strain,and relax the internal stress,mainly induced by the unavoidable volume variation during the repeated conversion processes.Moreover,it can provide more Na^(+)-storage sites and multi-directional migration pathways,leading to a fast Na^(+)-migration channel with boosted reaction kinetic.As expected,it delivers superior rate performance(441 mA h g^(-1)at 5.0 A g^(-1))and long cycling stability(563 mA h g^(-1)at 1.0 A g^(-1)over 1000 cycles)for SIBs.This work provides useful insights for designing high-performance conversion-based anode materials for SIBs. 展开更多
关键词 Stress dissipation multi-dimensional architecture Structure engineering Conversion-based anodes Sodium-ion batteries
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Research on Multi-Dimensional Collaborative Strategies in Design Management,Investment Management,and Beyond from the Perspective of Whole-Process Engineering Consulting
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作者 Zexin Chen 《Journal of Architectural Research and Development》 2025年第5期21-28,共8页
This paper explores whole-process engineering consulting,including its application models in public buildings and elderly-friendly projects,such as service integration and whole lifecycle management.It also addresses ... This paper explores whole-process engineering consulting,including its application models in public buildings and elderly-friendly projects,such as service integration and whole lifecycle management.It also addresses the construction of multi-dimensional collaborative theoretical models,public space streamline organization,and other aspects,emphasizing the importance of multi-dimensional collaboration.Additionally,it highlights the role of talent cultivation and digital transformation in enhancing project efficiency. 展开更多
关键词 Whole-process engineering consulting multi-dimensional collaboration Project efficiency
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Practical Application of the Multi-Dimensional Interactive Teaching Model in College English
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作者 Bo Sun 《Journal of Contemporary Educational Research》 2025年第10期106-111,共6页
The multi-dimensional interactive teaching model significantly enhances the effectiveness of college English instruction by emphasizing dynamic engagement between teachers and students,as well as among students themse... The multi-dimensional interactive teaching model significantly enhances the effectiveness of college English instruction by emphasizing dynamic engagement between teachers and students,as well as among students themselves.This paper explores practical strategies for implementing this model,focusing on four key aspects:deepening teachers’understanding of the model through continuous learning,innovating interactive methods such as questioning techniques and practical activities,leveraging modern technology to integrate resources and track learning progress,and establishing a communication platform that centers on student participation.By adopting these approaches,the model fosters a student-centered classroom environment,improves comprehensive English application skills,and optimizes overall teaching quality. 展开更多
关键词 multi-dimensional interactive teaching model Student-centered approach Teacher-student interaction
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Construction of the Practice System of Landscape Architecture Major Based on“Multi-dimensional Integration”
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作者 LI Yinan DING Juan +4 位作者 ZHU Yan WU Jing ZHAO Zhiyan LI Jie XIANG Cheng 《Journal of Landscape Research》 2025年第3期89-92,共4页
During the critical transformation period of landscape architecture major after the adjustment of disciplinary structure and the changes in market demand,private colleges and universities,as important places for culti... During the critical transformation period of landscape architecture major after the adjustment of disciplinary structure and the changes in market demand,private colleges and universities,as important places for cultivating local talents,have pain points such as uneven quality of teachers and students and weak innovation and practice.The practice system with“multi-dimensional Integration”integrates four dimensions:interdisciplinary integration,spatial and temporal intersection,historical inheritance,and behavioral activity,deepens the disciplinary connotation,and integrates the three elements of nature,humanity,and technology,aiming to provide a new path for private colleges and universities to cultivate application-oriented and compound talents with innovative capabilities.In terms of optimizing talent cultivation and adapting to industry changes,this system provides thinking and reference for landscape architecture major,helping the major reshape its core competitiveness and promoting educational innovation and industry development. 展开更多
关键词 Landscape architecture Practice system multi-dimensional integration”model Talent cultivation Teaching reform
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Reliability of multi-dimensional network systems with nodes having stochastic connection ranges
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作者 FU Yuqiang MA Xiaoyang ZHAO Fei 《Journal of Systems Engineering and Electronics》 2025年第4期1017-1023,共7页
This paper proposes a reliability evaluation model for a multi-dimensional network system,which has potential to be applied to the internet of things or other practical networks.A multi-dimensional network system with... This paper proposes a reliability evaluation model for a multi-dimensional network system,which has potential to be applied to the internet of things or other practical networks.A multi-dimensional network system with one source element and multiple sink elements is considered first.Each element can con-nect with other elements within a stochastic connection ranges.The system is regarded as successful as long as the source ele-ment remains connected with all sink elements.An importance measure is proposed to evaluate the performance of non-source elements.Furthermore,to calculate the system reliability and the element importance measure,a multi-valued decision diagram based approach is structured and its complexity is analyzed.Finally,a numerical example about the signal transfer station system is illustrated to analyze the system reliability and the ele-ment importance measure. 展开更多
关键词 multi-dimensional network multi-valued decision diagram stochastic connection range reliability analysis impor-tance measure.
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Multi-dimensional hydrogen bonds regulated emissions of single-molecule system enabling surficial hydrophobicity/hydrophilicity mapping
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作者 Hao Gu Rui Li +6 位作者 Qiuying Li Sheng Lu Yahui Chen Xiaoning Yang Huili Ma Zhijun Xu Xiaoqiang Chen 《Chinese Chemical Letters》 2025年第5期515-520,共6页
Constructing multi-dimensional hydrogen bond(H-bond)regulated single-molecule systems with multiemission remains a challenge.Herein,we report the design of a new excited-state intramolecular proton transfer(ESIPT)feat... Constructing multi-dimensional hydrogen bond(H-bond)regulated single-molecule systems with multiemission remains a challenge.Herein,we report the design of a new excited-state intramolecular proton transfer(ESIPT)featured chromophore(HBT-DPI)that shows flexible emission tunability via the multidimensional regulation of intra-and intermolecular H-bonds.The feature of switchable intramolecular Hbonds is induced via incorporating several hydrogen bond acceptors and donors into one single HBT-DPI molecule,allowing the“turn on/off”of ESIPT process by forming isomers with distinct intramolecular Hbonds configurations.In response to different external H-bonding environments,the obtained four types of crystal/cocrystals vary in the contents of isomers and the molecular packing modes,which are mainly guided by the intermolecular H-bonds,exhibiting non-emissive features or emissions ranging from green to orange.Utilizing the feature of intermolecular H-bond guided molecular packing,we demonstrate the utility of this fluorescent material for visualizing hydrophobic/hydrophilic areas on large-scale heterogeneous surfaces of modified poly(1,1-difluoroethylene)(PVDF)membranes and quantitatively estimating the surface hydrophobicity,providing a new approach for hydrophobicity/hydrophilicity monitoring and measurement.Overall,this study represents a new design strategy for constructing multi-dimensional hydrogen bond regulated ESIPT-based fluorescent materials that enable multiple emissions and unique applications. 展开更多
关键词 multi-dimensional hydrogen bonds Emission regulation Hydrophobicity/hydrophilicity Surficial mapping Excited-state intramolecular proton transfer
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A novel multi-dimensional isolation platform for low-frequency excitations:analysis and experiment
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作者 Lingjun MENG Xiuting SUN Jian XU 《Applied Mathematics and Mechanics(English Edition)》 2025年第12期2241-2264,共24页
To break the limitations of the multi-dimensional(M-D)vibration isolation(VI)platforms with the Stewart-Gough design,such as strongly coupling motions,excessive friction in connections,heavy weight,and limited workspa... To break the limitations of the multi-dimensional(M-D)vibration isolation(VI)platforms with the Stewart-Gough design,such as strongly coupling motions,excessive friction in connections,heavy weight,and limited workspace,this study processes a novel platform integrated by a stiffness-adjustable origami spring sub-structure and a parallel mechanism.The origami-based stiffness-adjustable spring realizes low-frequency VI,and the parallel mechanism symmetry design realizes motions decoupling.In the origami-based sub-leg,the parallel-stack-assembly(PSA)design mechanism with two Miura origami configurations is proposed to generate a symmetrical negative stiffness property.Paired with a linear positive stiffness spring,the origami-based sub-leg has wide-amplitude-high-static-low-dynamic stiffness(WA-HSLDS)characteristics in one direction.Then,with construction of the parallel mechanism connected with origami-based sub-legs,an M-D VI platform is achieved,whose motions in the vertical direction and yaw direction are decoupled with the motions in the other directions.Based on the dynamic model and incremental harmonic balance(IHB)with the arc-length continuation method,appropriate structural parameters in the parallel mechanism part are figured out,and the accurate transmissibility in different directions is defined,which gives the parametric influencing investigations for realization of low-frequency VI performances.Finally,experiments are conducted to validate the accuracy and feasibility of the theoretical methods,and to demonstrate the performance of M-D low-frequency isolation with load-carrying capacity of the proposed VI platform.The integration of the origami into the parallel mechanism results in a compact,efficient,and flexible platform with nonlinear adjustability,offering new possibilities for lightweight M-D VI,and developing the practical applications in high-precision platforms in ocean and aerospace environments. 展开更多
关键词 multi-dimensional(M-D)vibration isolation(VI) wide-amplitude high-static-low-dynamic stiffness(WA-HSLDS) origami-based elastic spring parallel mechanism
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Synthesis,structural characterization,electrocatalytic proton reduction,and fungicidal activity of thiazole‑containing di‑iron complexes
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作者 JIANG Chengyu LIU Xufeng 《无机化学学报》 北大核心 2026年第2期355-364,共10页
This paper reports the preparation of three di‑iron complexes containing a thiazole moiety.Esterification of complex[Fe_(2)(CO)_(6)(μ‑SCH_(2)CH(CH_(2)OH)S)](1)with 4‑methylthiazole‑5‑carboxylic acid gave the correspo... This paper reports the preparation of three di‑iron complexes containing a thiazole moiety.Esterification of complex[Fe_(2)(CO)_(6)(μ‑SCH_(2)CH(CH_(2)OH)S)](1)with 4‑methylthiazole‑5‑carboxylic acid gave the corresponding ester[Fe_(2)(CO)_(6)(μ‑tedt)](2),where tedt=SCH_(2)CH(CH_(2)OOC(5‑C_(3)HNSCH_(3)))S.Further reactions of complex 2 with tri(ptolyl)phosphine(tp)or tris(4‑fluorophenyl)phosphine(fp)gave the phosphine‑substituted derivatives[Fe_(2)(CO)_(5)(tp)(μ‑tedt)](3)and[Fe_(2)(CO)_(5)(fp)(μ‑tedt)](4).The structures of the newly prepared complexes were elucidated by elemental analysis,NMR,IR,and X‑ray photoelectron spectroscopy.Moreover,single‑crystal X‑ray diffraction analysis confirmed their molecular structures,showing that they contain a di‑iron core ligated by a bridged dithiolate bearing a thiazole moiety and terminal carbonyls.The electrochemical and electrocatalytic proton reduction were probed by cyclic voltammetry,revealing that three complexes can catalyze the reduction of protons to H_(2) under the electrochemical conditions.For comparison,complex 4 possessed the best efficiency with a turnover frequency of 23.5 s^(-1)at 10 mmol·L^(-1)HOAc concentration.In addition,the fungicidal activity of these complexes was also investigated in this study.CCDC:2477511,2;2477512,3;2477513,4. 展开更多
关键词 THIAZOLE di‑iron complex crystal structure electrocatalytic proton reduction fungicidal activity
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The critical role of iron homeostasis in neurodegenerative diseases
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作者 Tiantian Liang Jiasen Xu +6 位作者 Yan Zhu He Zhao Xiaoyu Zhai Qi Wang Xiaohui Ma Limei Cui Yan Sun 《Neural Regeneration Research》 2026年第5期1723-1737,共15页
Neurodegenerative diseases are prevalent conditions that greatly impact human health.These diseases are primarily characterized by the progressive loss and eventual death of neuronal function,although the precise mech... Neurodegenerative diseases are prevalent conditions that greatly impact human health.These diseases are primarily characterized by the progressive loss and eventual death of neuronal function,although the precise mechanisms underlying these processes remain incompletely understood.Iron is an essential trace element in the human body,playing a crucial role in various biological processes.The maintenance of iron homeostasis relies on the body's intricate and nuanced regulatory mechanisms.In recent years,considerable attention has been directed toward the relationship between dysregulated iron homeostasis and neurodegenerative diseases.The regulation of iron homeostasis within cells is crucial for maintaining proper nervous system function.Research has already revealed that disruptions in iron homeostasis may lead to ferroptosis and oxidative stress,which,in turn,can impact neuronal health and contribute to the development of neurodegenerative diseases.This article primarily explores the intimate relationship between iron homeostasis and neurodegenerative diseases,aiming to provide novel insights and strategies for treating these debilitating conditions. 展开更多
关键词 ferroprotein neurodegenerative diseases iron homeostasis iron iron regulatory proteins
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Thermal simulation method for researching solidification process of ductile iron pipe based on heat transfer similarity of characteristic unit of ductile iron pipe
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作者 Gan-chao Zhai Gong-ao Zhu +4 位作者 Shao-dong Hu Bin Yang Jie-yu Zhang Xiang-ru Chen Qi-jie Zhai 《China Foundry》 2026年第1期62-72,共11页
Centrifugal casting of ductile iron pipe is a high-temperature,semi-continuous production process.However,conducting laboratory research on the solidification process of centrifugal casting of ductile iron pipe presen... Centrifugal casting of ductile iron pipe is a high-temperature,semi-continuous production process.However,conducting laboratory research on the solidification process of centrifugal casting of ductile iron pipe presents significant challenges.In this study,a novel research method was introduced for investigating the solidification process of ductile iron pipe,namely thermal simulation of ductile iron pipe.Comparative research was conducted on the microstructure and properties of the thermal simulation sample and the ductile iron pipe.The findings indicate that the thermal simulation sample and ductile iron pipe exhibit good heat transfer similarity and microstructure similarity.The difference of cooling rate between thermal simulation sample and ductile pipe is less than 0.24℃·s^(-1),and the difference of microstructure content of free cementite,ferrite,and pearlite is less than 5%.The tensile strength of annealed ductile iron pipe is 466 MPa,with an elongation of 16.1%and a Brinell hardness of 156.5 HBW.In comparison,the tensile strength of annealed thermal simulation sample is 482.0 MPa,with an elongation of 15.5%and a Brinell hardness of 159.0 HBW.These results suggest that the thermal simulation experimental research method is both scientific and feasible,offering an objective,reliable,and cost-effective approach to laboratory research on ductile iron pipe. 展开更多
关键词 ductile iron pipe centrifugal casting thermal simulation MICROSTRUCTURE mechanical property
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Iron dyshomeostasis links obesity and neurological diseases
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作者 Bandy Chen 《Neural Regeneration Research》 2026年第5期1985-1986,共2页
With the industrialization of agriculture and the advancement of medical care,human life expectancy has increased considerably and continues to rise steadily.This results in novel and unprecedented challenges,namely o... With the industrialization of agriculture and the advancement of medical care,human life expectancy has increased considerably and continues to rise steadily.This results in novel and unprecedented challenges,namely obesity and neurodegeneration. 展开更多
关键词 industrialization agriculture human life expectancy OBESITY medical care advancement neurological diseases iron dysregulation NEURODEGENERATION
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Magnetic resonance imaging tracing of superparamagnetic iron oxide nanoparticle-labeled mesenchymal stromal cells for repairing spinal cord injury
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作者 Xiaoli Mai Yuanyuan Xie +12 位作者 Zhichong Wu Junting Zou Jiacheng Du Yunpeng Shen Hao Liu Bo Chen Mengxia Zhu Jiong Shi Yang Chen Bing Zhang Zezhang Zhu Bin Wang Ning Gu 《Neural Regeneration Research》 2026年第5期2031-2039,共9页
Mesenchymal stromal cell transplantation is an effective and promising approach for treating various systemic and diffuse diseases.However,the biological characteristics of transplanted mesenchymal stromal cells in hu... Mesenchymal stromal cell transplantation is an effective and promising approach for treating various systemic and diffuse diseases.However,the biological characteristics of transplanted mesenchymal stromal cells in humans remain unclear,including cell viability,distribution,migration,and fate.Conventional cell tracing methods cannot be used in the clinic.The use of superparamagnetic iron oxide nanoparticles as contrast agents allows for the observation of transplanted cells using magnetic resonance imaging.In 2016,the National Medical Products Administration of China approved a new superparamagnetic iron oxide nanoparticle,Ruicun,for use as a contrast agent in clinical trials.In the present study,an acute hemi-transection spinal cord injury model was established in beagle dogs.The injury was then treated by transplantation of Ruicun-labeled mesenchymal stromal cells.The results indicated that Ruicunlabeled mesenchymal stromal cells repaired damaged spinal cord fibers and partially restored neurological function in animals with acute spinal cord injury.T2*-weighted imaging revealed low signal areas on both sides of the injured spinal cord.The results of quantitative susceptibility mapping with ultrashort echo time sequences indicated that Ruicun-labeled mesenchymal stromal cells persisted stably within the injured spinal cord for over 4 weeks.These findings suggest that magnetic resonance imaging has the potential to effectively track the migration of Ruicun-labeled mesenchymal stromal cells and assess their ability to repair spinal cord injury. 展开更多
关键词 acute spinal cord injury diffusion tensor imaging dynamic migration mesenchymal stromal cells neural function neuronal regeneration quantitative susceptibility mapping repairability ruicun superparamagnetic iron oxide nanoparticle
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The Study on College English Writing Based on Multi-dimensional Feed-back Mode
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作者 骆敏 徐敏娜 《海外英语》 2020年第12期273-274,共2页
The study constructed a multi-dimensional feedback mode integrating teacher feedback, peer feedback and network feedback, and applied it in the teaching of College English Writing. After 16 weeks of teaching, the stud... The study constructed a multi-dimensional feedback mode integrating teacher feedback, peer feedback and network feedback, and applied it in the teaching of College English Writing. After 16 weeks of teaching, the students in the multi-dimen-sional feedback class had significantly better overall writing scores than those in the teacher-feedback class. In terms of individual scores, multi-dimensional feedback played a better role in improving vocabulary and grammar than the class using teacher feed-back. However, there were no significant differences in the responses of writing tasks, coherence and cohesion. The study showed that most students were satisfied with the mode, believing that it was helpful to relieve writing anxiety, stimulate writing interest and improve their writing level. 展开更多
关键词 College English Writing multi-dimensional feedback MODE
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Structural Engineering of Hierarchical Aerogels Comprised of Multi-dimensional Gradient Carbon Nanoarchitectures for Highly Efficient Microwave Absorption 被引量:19
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作者 Yongpeng Zhao Xueqing Zuo +11 位作者 Yuan Guo Hui Huang Hao Zhang Ting Wang Ningxuan Wen Huan Chen Tianze Cong Javid Muhammad Xuan Yang Xinnan Wang Zeng Fan Lujun Pan 《Nano-Micro Letters》 SCIE EI CAS CSCD 2021年第9期344-363,共20页
Recently,multilevel structural carbon aerogels are deemed as attractive candidates for microwave absorbing materials.Nevertheless,excessive stack and agglomeration for low-dimension carbon nanomaterials inducing imped... Recently,multilevel structural carbon aerogels are deemed as attractive candidates for microwave absorbing materials.Nevertheless,excessive stack and agglomeration for low-dimension carbon nanomaterials inducing impedance mismatch are significant challenges.Herein,the delicate“3D helix-2D sheet-1D fiber-0D dot”hierarchical aerogels have been successfully synthesized,for the first time,by sequential processes of hydrothermal self-assembly and in-situ chemical vapor deposition method.Particularly,the graphene sheets are uniformly intercalated by 3D helical carbon nanocoils,which give a feasible solution to the mentioned problem and endows the as-obtained aerogel with abundant porous structures and better dielectric properties.Moreover,by adjusting the content of 0D core-shell structured particles and the parameters for growth of the 1D carbon nanofibers,tunable electromagnetic properties and excellent impedance matching are achieved,which plays a vital role in the microwave absorption performance.As expected,the optimized aerogels harvest excellent performance,including broad effective bandwidth and strong reflection loss at low filling ratio and thin thickness.This work gives valuable guidance and inspiration for the design of hierarchical materials comprised of dimensional gradient structures,which holds great application potential for electromagnetic wave attenuation. 展开更多
关键词 Hierarchical aerogels multi-dimensional gradient Carbon nanocoils Microwave absorption
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Seismic fragility analysis of highway bridges considering multi-dimensional performance limit state 被引量:17
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作者 Wang, Qi'ang Wu, Ziyan Liu, Shukui 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2012年第2期185-193,共9页
Fragility analysis for highway bridges has become increasingly important in the risk assessment of highway transportation networks exposed to seismic hazards. This study introduces a methodology to calculate fragility... Fragility analysis for highway bridges has become increasingly important in the risk assessment of highway transportation networks exposed to seismic hazards. This study introduces a methodology to calculate fragility that considers multi-dimensional performance limit state parameters and makes a first attempt to develop fragility curves for a multi-span continuous (MSC) concrete girder bridge considering two performance limit state parameters: column ductility and transverse deformation in the abutments. The main purpose of this paper is to show that the performance limit states, which are compared with the seismic response parameters in the calculation of fragility, should be properly modeled as randomly interdependent variables instead of deterministic quantities. The sensitivity of fragility curves is also investigated when the dependency between the limit states is different. The results indicate that the proposed method can be used to describe the vulnerable behavior of bridges which are sensitive to multiple response parameters and that the fragility information generated by this method will be more reliable and likely to be implemented into transportation network loss estimation. 展开更多
关键词 highway bridge seismic hazard multi-dimensional performance limit state fragility curves sensitivity
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Applications of multi-dimensional schemes on unstructured grids for high-accuracy heat flux prediction 被引量:2
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作者 Yunbo Wan Nianhua Wang +1 位作者 Laiping Zhang Yewei Gui 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2020年第1期57-71,共15页
The simulation of hypersonic flows with fully unstructured(tetrahedral)grids has severe problems with respect to the prediction of stagnation region heating,due to the random face orientation without alignment to the ... The simulation of hypersonic flows with fully unstructured(tetrahedral)grids has severe problems with respect to the prediction of stagnation region heating,due to the random face orientation without alignment to the bow shock.To improve the accuracy of aero-heating predictions,three multi-dimensional approaches on unstructured grids are coupled in our Reynolds-averaged Navier-Stokes(RANS)solver,including multi-dimensional upwind flux reconstruction(MUP),multi-dimensional limiter(MLP-u2)and multi-dimensional gradient reconstruction(MLR).The coupled multi-dimensional RANS solver is validated by several typical verification and validation(V&V)cases,including hypersonic flows over a cylinder,a blunt biconic,and a double-ellipsoid,with commonly used prism/tetrahedral hybrid grids.Finally,the coupled multi-dimensional solver is applied to simulating the heat flux distribution over a 3D engineering configuration,i.e.a Hermes-like space shuttle model.The obtained numerical results are compared with experimental data.The predicted results demonstrate that the coupled multi-dimensional approach has a good prediction capability on aerodynamic heating over a wide range of complex engineering configurations. 展开更多
关键词 Heat-flux prediction Unstructured grid multi-dimensional gradient reconstruction multi-dimensional limiter multi-dimensional upwind scheme
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Hydraulic directional valve fault diagnosis using a weighted adaptive fusion of multi-dimensional features of a multi-sensor 被引量:12
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作者 Jin-chuan SHI Yan REN +1 位作者 He-sheng TANG Jia-wei XIANG 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2022年第4期257-271,共15页
Because the hydraulic directional valve usually works in a bad working environment and is disturbed by multi-factor noise,the traditional single sensor monitoring technology is difficult to use for an accurate diagnos... Because the hydraulic directional valve usually works in a bad working environment and is disturbed by multi-factor noise,the traditional single sensor monitoring technology is difficult to use for an accurate diagnosis of it.Therefore,a fault diagnosis method based on multi-sensor information fusion is proposed in this paper to reduce the inaccuracy and uncertainty of traditional single sensor information diagnosis technology and to realize accurate monitoring for the location or diagnosis of early faults in such valves in noisy environments.Firstly,the statistical features of signals collected by the multi-sensor are extracted and the depth features are obtained by a convolutional neural network(CNN)to form a complete and stable multi-dimensional feature set.Secondly,to obtain a weighted multi-dimensional feature set,the multi-dimensional feature sets of similar sensors are combined,and the entropy weight method is used to weight these features to reduce the interference of insensitive features.Finally,the attention mechanism is introduced to improve the dual-channel CNN,which is used to adaptively fuse the weighted multi-dimensional feature sets of heterogeneous sensors,to flexibly select heterogeneous sensor information so as to achieve an accurate diagnosis.Experimental results show that the weighted multi-dimensional feature set obtained by the proposed method has a high fault-representation ability and low information redundancy.It can diagnose simultaneously internal wear faults of the hydraulic directional valve and electromagnetic faults of actuators that are difficult to diagnose by traditional methods.This proposed method can achieve high fault-diagnosis accuracy under severe working conditions. 展开更多
关键词 Hydraulic directional valve Internal fault diagnosis Weighted multi-dimensional features Multi-sensor information fusion
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