检索结果-内蒙古大学图书馆

arXiv 2022年

作者： Wang, Yancong Yu, Linfeng Zhang, Fa Chen, Qiang Zhan, Yuqi Zheng, Xiong Wang, Huimin Qin, Zhenzhen Qin, Guangzhao State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body College of Mechanical and Vehicle Engineering Hunan University Changsha410082 China State Key Laboratory of Robotics and System Harbin Institute of Technology Harbin150001 China Hunan Key Laboratory for Micro-Nano Energy Materials & Device School of Physics and Optoelectronics Xiangtan University Hunan Xiangtan411105 China School of Physics and Microelectronics Zhengzhou University Zhengzhou450001 China

Negative Poisson's ratio (NPR) is of great interest due to the novel applications in lots of fields. Films are the most commonly used form in practical applications, which involves multiple layers. However, the effect of interlayer interactions on the NPR is still unclear. In this study, based on first principles calculations, we systematically investigate the effect of interlayer interactions on the NPR by comparably studying single-layer graphene, few-layer graphene, h-BN, and graphene-BN heterostructure. It is found that they almost have the same geometry-strain response. Consequently, the NPR in bilayer graphene, triple-layer graphene, and graphene-BN heterostructure are consistent with that in single-layer graphene and h-BN. The fundamental mechanism lies in that the response to strain of the orbital coupling are consistent under the effect of interlayer interactions. The deep understanding of the NPR with the effect of interlayer interactions as achieved in this study is beneficial for the future design and development of micro-/nanoscale electromechanical devices with novel functions based on nanostructures. © 2022, CC BY-NC-SA.

关键词： Graphene

来源：评论

学校读者我要写书评

暂无评论

Study on mechanical Properties of Dual-Channel Cryogenic 3d Printing Scaffold for Mandibular Defect Repair

SSRN

引用

SSRN 2023年

作者： Gao, Lilan Sun, Mengchao Liu, Jie Meng, Lulu Liu, Han Zheng, Xiongfei Liu, Hao Li, Ruixin Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control School of Mechanical Engineering Tianjin University of Technology Tianjin300382 China Tianjin300382 China Beijing Friendship Hospital Capital Medical University 100050 China State Key Laboratory of Robotics Institutes for Robotics and Intelligent Manufacturing Shenyang Institute of Automation Chinese Academy of Sciences Shenyang110017 China Tianjin Key Laboratory of Oral and Maxillofacial Function Reconstruction Tianjin Stomatological Hospital The Affiliated Stomatological Hospital of Nankai University Tianjin300041 China

Mandibular defect repair has always been a clinical challenge, facing technical bottleneck. The new materials directly affect technological breakthroughs in mandibular defect repair field. Our aim is to fabricate a scaffold for mandibular defect repairing with advanced biomaterials. Therefore, a novel dual-channel printed scaffold consisting of silk fibroin/collagen type I /hydroxyapatite (SCH) and polycaprolactone/hydroxyapatite (PCL/HA) was fabricated by 3D printing technology with double nozzles. The mechanical properties and behaviors of dual-channel printed scaffold were investigated by performing uniaxial compression, creep, stress relaxation and ratcheting experiments respectively. The experiments indicated the Young modulus of dual-channel printed scaffold was 60.1 kPa and dual-channel printed scaffold was typical nolinear viscoelastic consistent with bone tissue. Finite Element Analysis (FEA) was employed performing a numerical simulation to evaluate the implantation effect in mandible. The stress distribution of the contact area between scaffold and defect was uniform, the maximum Mises stress of cortical bone and cancellous bone in defect area were 54.52MPa and 3.196MPa, and the maximum displacement of cortical bone and cancellous bone in defect area were 0.1575mm and 0.1555mm, which were distributed in the incisor region. The peak value of the maximum Mises stress for the scaffold implanted was 3.128× MPa and the maximum displacement was 6.453×mm distributed near incisor area. The displacement distribution of the scaffold was consistent with that of cortical and cancellous bone. The scaffold recovered well when the force applied on it disappeared. Above all, dual-channel printed scaffold had excellent bio-mechanical properties in implanting mandible, which provides a new idea for the reconstruction of irregular bone defects in the mandible and has good clinical development prospects. © 2023, The Authors. All rights reserved.

关键词： 3D printing

来源：评论

学校读者我要写书评

暂无评论

Overcoming Van der Waals Forces in reconfigurable nanostructures

arXiv

引用

arXiv 2022年

作者： Zhang, Wang Wang, Hao Tan, Alvin T.L. Ranganath, Anupama Sargur Zhang, Biao Wang, Hongtao Chan, John You En Ruan, Qifeng Liu, Hailong Ha, Son Tung Wang, Dong Ravikumar, Venkat K. Low, Hong Yee Yang, Joel K.W. Engineering Product Development Singapore University of Technology and Design Singapore487372 Singapore Northwestern Polytechnical University 127 West Youyi Road Xi'An710072 China Institute of Materials Research and Engineering Singapore138634 Singapore Robotics Institute State Key Laboratory of Mechanical System and Vibration School of Mechanical Engineering Shanghai Jiao Tong University Shanghai200240 China Advanced Micro Devices Singapore Pte Ltd Singapore Singapore

Reconfigurable metamaterials1-3 require constituent nanostructures to demonstrate switching of shapes with external stimuli. For generality, such nanostructures would touch and stick to other surfaces in one of its configurations. Yet, a longstanding challenge is in overcoming this stiction caused by Van der Waals forces, which impedes shape recovery. Here, we introduce a stiff yet self-recovering material system based on acrylic acid, and tested it in high-aspect ratio structures, where recovery is weak. This designer material has a storage modulus of ~5.2 GPa at room temperature and ~90 MPa in the rubbery state at 150 ℃, an order of magnitude higher than previous reports. A high-resolution resin for two-photon lithography was developed based on this polymer system, enabling 3D printing of nanopillars with diameters of ~400 nm and aspect ratio as high as ~10. Experimentally, we observed self-recovery as collapsed and touching structures overcome stiction to stand back up. We developed a theoretical model to explain the recoverability of these sub-micron structures. Reconfigurable structural colour prints and holograms were demonstrated, indicating potential applications of the material system as a shape memory polymer suitable for sub-micron reconfigurable metamaterials. Copyright © 2022, The Authors. All rights reserved.

关键词： Van der Waals forces

来源：评论

学校读者我要写书评

暂无评论

Bio-robotics research for non-invasive myoelectric neural interfaces for upper-limb prosthetic control: a 10-year perspective review

引用

National Science Review 2023年第5期 38-58页

作者：江宁陈晨何家源孟建军潘立志苏世勇朱向阳 National Clinical Research Center for Geriatrics West China Hospitaland Med-X Center for ManufacturingSichuan University State Key Laboratory of Mechanical System and Vibration and Institute of RoboticsShanghai Jiao Tong University Key Laboratory of Mechanism Theory and Equipment Design of Ministry of Education School of Mechanical EngineeringTianjin University Institute of Neuroscience Université Catholique Louvain

A decade ago,a group of researchers from academia and industry identified a dichotomy between the industrial and academic state-of-the-art in upper-limb prosthesis control,a widely used bio-robotics *** proposed that four key technical challenges,if addressed,could bridge this gap and translate academic research into clinically and commercially viable *** challenges are unintuitive control schemes,lack of sensory feedback,poor robustness and single sensor ***,we provide a perspective review on the research effort that occurred in the last decade,aiming at addressing these *** addition,we discuss three research areas essential to the recent development in upper-limb prosthetic control research but were not envisioned in the review 10 years ago:deep learning methods,surface electromyogram decomposition and open-source *** conclude the review,we provide an outlook into the near future of the research and development in upper-limb prosthetic control and beyond.

关键词：

来源：评论

学校读者我要写书评

暂无评论

BAN: A Universal Paradigm for Cross-Scene Classification Under Noisy Annotations From RGB and Hyperspectral Remote Sensing Images

引用

IEEE Transactions on Geoscience and Remote Sensing 2025年 63卷

作者： Chen, Wentang Wen, Yibin Zheng, Juepeng Huang, Jianxi Fu, Haohuan Sun Yat-sen University School of Artificial Intelligence Zhuhai519082 China Zhejiang University State Key Laboratory of Fluid Power and Mechatronic Systems Engineering Research Center for Design Engineering and Digital Twin of Zhejiang Province School of Mechanical Engineering Robotics Institute Hangzhou310027 China Southwest Jiaotong University Faculty of Geosciences and Engineering Chengdu610032 China China Agricultural University College of Land Science and Technology Beijing100107 China Ministry of Agriculture and Rural Affairs Key Laboratory of Remote Sensing for Agri-Hazards Beijing100125 China Tsinghua University Tsinghua Shenzhen International Graduate School Shenzhen518071 China Tsinghua University Ministry of Education Key Laboratory for Earth System Modeling Department of Earth System Science Beijing100190 China National Supercomputer Center in Shenzhen Shenzhen518071 China

While domain adaptation (DA) methods have made significant strides in remote sensing community, most current works assume that the source domain labels are accurate. However, limited emphasis has been placed on the scenario where source data are mislabeled with noisy annotations, which is more common in real applications and referred to as noisy DA (NDA). This article formulates remote sensing cross-scene classification on NDA scenarios and proposes a novel network called bilateral adaptation network (BAN), which consists of two parts: 1) forward learning (FL), which utilizes a model learning from the noisy source domain and transfers knowledge to target domain;and 2) backward learning (BL), which utilizes a dual model to acquire knowledge from the target domain and transfer it to source domain. We conduct two parts alternately and adopt a symmetrical Kullback-Leibler (KL) loss to align predictions of the model and its dual model in the same domain. This interactive strategy is able to explore bilateral relationships between domains, implicitly reducing label noise in the source domain. In addition, BAN could serve as a universal paradigm to not only improve the existing NDA methods but also enhance recent DA approaches. Comprehensive evaluations on three publicly available RGB-band remote sensing datasets and two hyperspectral datasets validate the superior effectiveness of our proposed BAN. BAN improves the average accuracy by 6.70%-15.70% on RGB datasets and overall accuracy (OA) by 1.36%-3.14% on hyperspectral datasets with flip-20% noise compared to other state-of-the-art DA and NDA approaches. Promising results indicate the potential of our approach in tackling more general and practical problems with noisy source domain. © 2025 IEEE.

关键词： Contrastive Learning

来源：评论

学校读者我要写书评

暂无评论

Anisotropy of thermal transport in phosphorene: A comparative first-principles study using different exchange-correlation functional

arXiv

引用

arXiv 2021年

作者： Zhang, Fa Zheng, Xiong Wang, Huimin Ding, Liang Qin, Guangzhao State Key Laboratory of Robotics and System Harbin Institute of Technology Harbin150001 China State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body College of Mechanical and Vehicle Engineering Hunan University Changsha410082 China Hunan Key Laboratory for Micro-Nano Energy Materials & Device School of Physics and Optoelectronics Xiangtan University Hunan Xiangtan411105 China

Phosphorene, as a new type of two-dimensional (2D) semiconductor material, possesses unique physical and chemical properties, and thus has attracted widespread attention in recent years. With its increasing applications in nano/optoelectronics and thermoelectrics, a comprehensive study on its thermal transport properties is necessary. It has been concluded from previous studies that there exist vast difference and uncertainty in the theoretically predicted thermal conductivity, which is generally attributed to the selection of XC functional. However, there is no comprehensive investigation on this issue. In this paper, based on first-principles calculations using 12 different exchange-correlation (XC) functionals, the phonon transport properties of phosphorene are systematically studied by solving the Boltzmann transport equation (BTE). The results show noticeable differences in the phonon transport properties of phosphorene under different XC functionals. For instance, the thermal conductivity of phosphorene along the zigzag direction ranges from 0.51 to 30.48 Wm−1K-1, and that along the armchair direction ranges from 0.15 to 5.24 Wm−1K−1. Moreover, the anisotropy of thermal conductivity is between 3.4 and 6.9, which is fundamentally originated from the special hinge-like structure. This study conducts an in-depth analysis of phonon transport to reveal the effect and mechanism of different XC functionals for predicting thermal transport properties, which would provide a reference for future research on phosphorene and other novel materials. © 2021, CC BY.

关键词： Anisotropy

来源：评论

学校读者我要写书评

暂无评论

Anisotropic tensile properties and high-cycle fatigue behavior of Ti6Al4V fabricated by single and dual laser-powder bed fusion

引用

Materials Science and Engineering: A 2025年 941卷

作者： Guotai Li Peichen Hu Yuzhan Fan Ming Wu Mingjun Chen Tianyu Yu State Key Laboratory of Robotics and System Harbin Institute of Technology Harbin Heilongjiang 150001 China Key Laboratory of Micro-systems and Micro-structures Manufacturing Ministry of Education Harbin Heilongjiang 150001 China Department of Computer Science KU Leuven 3001 Leuven Belgium Department of Mechanical Engineering KU Leuven 3001 Leuven Belgium

The development of multi laser-powder bed fusion (PBF) technology has significantly reduced the production time for large engine components. However, the impact of thermal effects and microstructural characteristics in the laser beam overlap region on the anisotropic mechanical behavior of metallic materials remains unclear. This study investigated the anisotropic tensile properties and high-cycle fatigue behavior of Ti6Al4V produced by both single laser-PBF (SL-PBF) and dual laser-PBF (DL-PBF). As-built DL-PBF samples exhibited high strength (1404 MPa) but low ductility (3.6 %). After heat treatment, the samples achieved a strength-ductility balance, with an ultimate tensile strength of 1089 MPa, and an elongation of 17.1 %. The mechanical properties of Ti6Al4V produced by DL-PBF were influenced by the α lath thickness, dislocation density and texture. The precipitation of small-angle grain boundaries during DL-PBF process was found to contribute to the strong anisotropy. Due to the influence of internal pore forming, the fatigue strength of the DL-PBF samples was lower than that of the SL-PBF samples. Pores in the dual-laser beam overlap region accelerated the fatigue crack propagation, resulting in a venation-like pattern. In contrast, cracks in the SL-PBF samples propagated in a circular pattern around internal pore. A high-speed camera was employed to capture the dual-laser beams dynamics during pore formation. This study provides a comprehensive analysis of the mechanical properties and pore formation mechanisms in the DL-PBF process.

关键词：

来源：评论

学校读者我要写书评

暂无评论

design and Experimental Evaluation of a Hexapod Mobile Robot with C-Shaped Legs

Design and Experimental Evaluation of a Hexapod Mobile Robot...

引用

International Conference on Advanced robotics and Mechatronics (ICARM)

作者： Yujie Wu Dangchao Li Xia Dong Xin Wang Chunli Zheng Aibin Zhu Zheng Zhang Xu Zhou Yulin Zhang Shaanxi Key Laboratory of Intelligent Robots Institute of Robotics & Intelligent Systems Xi'an Jiaotong University Xi'an China Key Laboratory of Education Ministry for Modern Design and Rotor-Bearing System Xi'an China School of Construction Machinery Chang'an University Xi'an China Xi'an Jiaotong University Xi'an China School of Energy and Power Engineering Xi'an Jiaotong University Xi'an China School of Mechanical Engineering Northwestern Polytechnical University Xi'an Taiyuan Research Institute of China Coal Technology & Engineering Group Co. Ltd Taiyuan China

Drawing on extant literature on hexapod robots, we present a novel obstacle-crossing hexapod robot that can adapt to multiple terrains. We designed the robot's entire mechanical structure, established a mathematical model for the robot leg, deduced the kinematic equation of the leg, and determined the relationship between the robot's motion speed and the motor angle. Through force analysis of the C-shaped leg, we obtained the function between motor output torque and motion phase. Subsequently, we constructed the physical hexapod robot and conducted performance testing. Our experimental results demonstrate that the hexapod robot can move at a speed of 0.5 m/s and successfully cross a 10 cm obstacle. The robot exhibits excellent movement performance and satisfies the functional requirements. Overall, our design offers a promising approach for developing hexapod robots that can navigate a variety of terrains.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Advanced Centroid State Estimation and Instability Detection Framework Leveraging UKF and AdvSAE-LSTM

引用

IEEE Sensors Journal 2025年

作者： Mao, Han Zhu, Aibin Tu, Yao Song, Jiyuan Zheng, Chunli Li, Meng Xu, Peng Shi, Lei Liu, Yang Li, Xiao Guan, Zhenpeng Xi'an Jiaotong University Institute of Robotics and Intelligent Systems Shaanxi Key Laboratory of Intelligent Robots Xi'an710049 China Key Laboratory of Education Ministry for Modern Design and Rotor-Bearing System Xi'an710049 China Xi'an Jiaotong University School of Energy and Power Engineering Xi'an710049 China Xi'an Jiaotong University School of Mechanical Engineering Xi'an710049 China Xi'an Jiaotong University Honghui Hospital Xi'an710000 China Xi'an Jiaotong University Department of Sports Xi'an710049 China Xi'an Jiaotong University Second Affiliated Hospital Department of General Surgery Xi'an710004 China Fourth Medical Center of PLA General Hospital Department of Rehabilitation Senior Department of Orthopedics Beijing100048 China Sports Medicine and Rehabilitation National Clinical Research Center for Orthopedics Beijing100048 China Peking University Shougang Hospital Orthopedics Department Beijing100144 China

With the growing aging population, fall detection has become a significant research focus in recent years. However, most existing studies have not effectively improved the accuracy of centroid state estimation in human instability, particularly in terms of multi-source information fusion. To address this, we propose a centroid state estimation method based on the Unscented Kalman Filter (UKF), integrating data from the five-link model and trunk IMU sensors, significantly enhancing both the accuracy and robustness of centroid state estimation. Experimental results demonstrate that the proposed method achieves estimation errors of 0.0099 m and 0.0226 m/s for centroid displacement and velocity in the x-direction, and 0.0006 m and 0.0099 m/s in the y-direction, indicating high accuracy. To overcome the reliance of traditional supervised learning methods on large amounts of labeled data for instability state estimation, we propose an unsupervised learning-based instability state estimation method, featuring the AdvSAE-LSTM model. Data from different sensors are preprocessed and independent training datasets are constructed, after which the feature maps from each sensor are concatenated to form a global feature map. Compared to baseline methods, the proposed approach significantly improves instability state detection performance. Specifically, when the SAS threshold is set to 0.02, both the False Positive Rate (FPR) and False Negative Rate (FNR) are 0%, with a detection delay of only 77.16 ms, achieving highly efficient and accurate estimation of human instability states. © 2025 IEEE.

关键词： Kalman filters

来源：评论

学校读者我要写书评

暂无评论

R-SIEL: a physics-informed learning algorithm for discovering dynamics of serial manipulators

引用

Expert systems with Applications 2025年 287卷

作者： Omar, Mohamed Li, Ruifeng Wang, Ke Asker, Ahmed State Key Laboratory of Robotics and System Harbin Institute of Technology Harbin150001 China Production and Mechanical Design Engineering Department Faculty of Engineering Mansoura University Mansoura35516 Egypt Zhengzhou Research Institute Harbin Institute of Technology Zhengzhou450000 China School of Engineering and Applied Sciences Nile University Giza12573 Egypt

Dynamic modeling is essential for serial manipulators’ design and control. Multi-body dynamics simulators, such as SIMULINK and Adams, can precisely replicate a robot's dynamic behavior but are incapable of determining its nonlinear dynamic model. This work aims to identify serial manipulators’ dynamics from simulation data, which extends the capability of using an algorithm that combines the Euler-Lagrange method and sparse identification of nonlinear dynamics (SINDy) with physics-based constraints and Akaike Information Criterion (AICc). The algorithm is called Recursive SINDy Euler-Lagrange (R-SIEL). The Euler-Lagrange method is used to construct a preliminary library of symbolic functions. The physics-informed constraints, which utilize the similarities between the symbolic coefficients of the dynamic equations, are employed to decrease the number of functions in the library to get a constrained library. SINDy is equipped with three kinds of constraints: the constrained library, the dataset, and similarities between links’ dynamic equations. The generation of the three distinct datasets—training, constraints, and testing data—uses simulated data from the MATLAB® SIMULINK environment. The algorithms of sequential threshold least-squares and L0-minimization are coded with the convex optimization package CVX to determine the best dynamic model. The resulting models are tested with the testing dataset, and based on the lowest AICc, the best model is chosen. The proposed algorithm is applied to different serial manipulators: 2DOF robot, Stanford, PRR robot, ABB SCARA, UR5, and KUKA KR4 AGILUS robots. The resulting model is validated with the dynamic model derived using the conventional Euler-Lagrange method. For the considered manipulators, the R-SIEL algorithm shows a high capability to identify the dynamic model compared to the one identified compared to the previous algorithm. © 2025 Elsevier Ltd

关键词： Lagrange multipliers

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：