检索结果-南通市图书馆

Discrimination for ablative control mechanism in solid-propellant rocket nozzle

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2009年第10期52卷 2911-2917页

作者： huang haiming XU XiaoLiang JIANG GuiQing Institute of Engineering Mechanics Beijing Jiaotong UniversityBeijing 100044China China Academy of Aerospace Aerodynamics Beijing 100074China

The ablation in solid-propellant rocket nozzle is a coupling process resulted by chemistry, heat and mass transfer. Based on the heat and mass transfer theory, the aero-thermo-dynamic, and thermo-chemical kinetics, the thermal-chemical ablation model is established. Simulations are completed on the heat flow field and chemical ablation in the nozzle with different concentrations, frequency factors and activation energy of H2. The calculation results show that the concentration and the activation energy of H2 can provoke the transformation of control mechanism, whereas the influence brought by the frequency factor of H2 is feeble under a high-temperature and high-pressure combustion circumstance. The discrimination for ablative control mechanism is dependent on both concentration and activation energy of H2. This study will be useful in handling ablation and thermal protection problem in the design of solid-propellant rocket.

关键词： nozzle ablation control mechanism activation energy frequency factor

A novel multi-modal tactile sensor design using thermochromic material

在线全文

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2019年第11期62卷 189-191页

作者： Fuchun SUN Bin FANG Hongxiang XUE Huaping LIU haiming huang Department of Computer Science and Technology Tsinghua University Key Lab of Industrial Computer Control Engineering of Hebei Province Yanshan University College of Information Engineering Shenzhen University

Tactile sensors are important for ensuring robotic perception [1], and their performance directly affects a robot’s capability for performing dexterous operations. These sensors mimic the tactile sensing capability of human hands. This is because the skin of human hands is involved in considerably meticulous works and can provide multi-

关键词： A novel multi-modal tactile sensor design using thermochromic material

Machine Learning-Based Multi-Modal Information Perception for Soft Robotic Hands

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Tsinghua Science and Technology 2020年第2期25卷 255-269页

作者： haiming huang Junhao Lin Linyuan Wu Bin Fang Zhenkun Wen Fuchun Sun College of Electronics and Information Engineering Shenzhen UniversityShenzhen 518060China Department of Computer Science and Technology Tsinghua UniversityTsinghua UniversityBeijing 100084China College of Computer Science and Software Engineering Shenzhen UniversityShenzhen 518060China

This paper focuses on multi-modal Information Perception(IP)for Soft Robotic Hands(SRHs)using Machine Learning(ML)algorithms.A flexible Optical Fiber-based Curvature Sensor(OFCS)is fabricated,consisting of a Light-Emitting Diode(LED),photosensitive detector,and optical *** the roughened optical fiber generates lower light intensity,which reflecting the curvature of the soft *** with the curvature and pressure information,multi-modal IP is performed to improve the recognition *** of gesture,object shape,size,and weight are implemented with multiple ML approaches,including the Supervised Learning Algorithms(SLAs)of K-Nearest Neighbor(KNN),Support Vector Machine(SVM),Logistic Regression(LR),and the unSupervised Learning Algorithm(un-SLA)of K-Means Clustering(KMC).Moreover,Optical Sensor Information(OSI),Pressure Sensor Information(PSI),and Double-Sensor Information(DSI)are adopted to compare the recognition *** experiment results demonstrate that the proposed sensors and recognition approaches are feasible and *** recognition accuracies obtained using the above ML algorithms and three modes of sensor information are higer than 85 percent for almost all ***,DSI is more accurate when compared to single modal sensor information and the KNN algorithm with a DSI outperforms the other combinations in recognition accuracy.

关键词： multi-modal sensors optical fiber gesture recognition object recognition Soft Robotic Hands(SRHs) Machine Learning(ML)

Skill Learning for Human-Robot Interaction Using Wearable Device

在线全文

学校读者我要写书评

暂无评论

Tsinghua Science and Technology 2019年第6期24卷 654-662页

作者： Bin Fang Xiang Wei Fuchun Sun haiming huang Yuanlong Yu Huaping Liu Department of Computer Science and Technology Tsinghua UniversityBeijing 100084China Fuzhou University Fuzhou 350108 China College of Information Engineering Shenzhen UniversityShenzhen 518060China

With the accelerated aging of the global population and escalating labor costs, more service robots are needed to help people perform complex tasks. As such, human-robot interaction is a particularly important research topic. To effectively transfer human behavior skills to a robot, in this study, we conveyed skill-learning functions via our proposed wearable device. The robotic teleoperation system utilizes interactive demonstration via the wearable device by directly controlling the speed of the motors. We present a rotation-invariant dynamicalmovement-primitive method for learning interaction skills. We also conducted robotic teleoperation demonstrations and designed imitation learning experiments. The experimental human-robot interaction results confirm the effectiveness of the proposed method.

关键词： skill learning interaction teleoperation dynamical movement primitive

Research progress of heterogeneous structure magnesium alloys:A review

在线全文

学校读者我要写书评

暂无评论

Journal of Magnesium and Alloys 2024年第6期12卷 2147-2181页

作者： Xiang Chen Junlei Zhang Min Wang Weizhang Wang Di Zhao haiming huang Qi Zhao Xiaofei Xu Hongxia Zhang Guangsheng huang Hubei Longzhong Laboratory Wuhan University of Technology Xiangyang Demonstration ZoneXiangyang 441000China College of Materials Science and Engineering Hubei University of Automotive TechnologyShiyan 442002China College of Materials Science and Engineering Kunming University of Science and TechnologyKunming 650093China Hubei Key Laboratory of Energy Storage and Power Battery(Hubei University of Automotive Technology) Shiyan 442002China College of Materials Science and Engineering Chongqing UniversityChongqing 400044China School of Mechanical Engineering Suzhou University of Science and TechnologySuzhou 215009China

In recent years,a new class of metallic materials featuring heterogeneous structures has *** materials consist of distinct soft and hard domains with significant differences in mechanical properties,allowing them to maintain high strength while offering superior ***(Mg)alloys,renowned for their low density,high specific strength,exceptional vibration damping,and electromagnetic shielding properties,exhibit tremendous potential as lightweight and functional *** their advantageous properties,high-strength Mg alloys often suffer from limited ***,the emergence of heterogeneous materials provides a fresh perspective for the development of Mg alloys with both high strength and *** article provided a fundamental overview of heterostructured materials and systematically reviewed the recent research progress in the design of Mg alloys with strength-ductility balance based on heterostructure *** review encompassed various aspects,including preparation methods,formation mechanisms of diverse heterostructures,and mechanical properties,both within domestic and international *** this basis,the article discussed the challenges encountered in the design and fabrication of heterostructured Mg alloys,as well as the urgent issues that require attention and resolution in the future.

关键词： Mg alloys Heterogeneous structure Processing techniques Strength and ductility Hetero-deformation induced stress Strain gradient

THERMAL SHOCK OF SEMI-INFINITE BODY WITH MULTI-PULSED INTENSE LASER RADIATION

在线全文

学校读者我要写书评

暂无评论

Acta Mechanica Solida Sinica 2010年第2期23卷 175-180页

作者： haiming huang 1 Fang Su Yue Sun(Institute of Engineering Mechanics,Beijing Jiaotong University,Beijing 100044,China) [a] Institute of Engineering Mechanics Beijing Jiaotong University Beijing 100044 China

In order to investigate the thermal shock and the heat conduction property of a target under multi-pulsed laser radiation, analytic expressions of both temperature and thermal stress fields in the target are deduced on the basis of the non-Fourier conduction law and the thermo-elastic theory. Taking a stainless steel target as an example, we can solve the analytic expressions under appropriate boundary conditions by using the finite difference method and MATLAB software, and then reveal the evolution law of both surplus temperaturt, and thermal stress in the target. The results indicate that the temperature curves in the target irradiated by a multi-pulsed laser take on a delayed character in different sections away from the boundary, which is only affected by its relaxation time. The front of the stress wave is very steep in the non-Fourier numerical solutions, which presents an obvious thermal shock, so it is necessary to consider the non-Fourier effect of semi-infinite body under the high energy laser radiation.

关键词： multi-pulsed laser non-Fourier effect thermal shock

Systemic low-grade inflammation associated with specific depressive symptoms:insights from network analyses of five independent NHANES samples

在线全文

学校读者我要写书评

暂无评论

General Psychiatry 2024年第2期37卷 284-288页

作者： Jingyu Lin haiming huang Tianmei Si Lin Chen Jingxu Chen Yun-Ai Su Beijing Huilongguan Hospital BeijingChina Department of Clinical Laboratory Peking University First HospitalBeijingChina Neuropsychopharmacology Peking University Institute of Mental HealthBeijingChina National Clinical Research Center for Mental Disorders BeijingChina

To the editor:Major depressive disorder(MDD)is a heterogeneous disorder with varying symptom presentations and underlying biological mechanisms.1 The mainstream neurobiological hypotheses of depression involve monoami... 详细信息

关键词： inflammation depress pituitary

黄铜矿型CuCrS_2电子结构的第一性原理计算

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

硅酸盐学报 2014年第9期42卷 1203-1208页

作者：黄海铭张琴湖北汽车工业学院理学院湖北十堰442002

利用基于密度泛函理论的第一性原理研究了黄铜矿CuCrS2的电子结构。结果表明:CuCrS2是一种半金属铁磁体,其半金属隙为0.18eV。每个CuCrS2分子的磁矩为3.00μB,Cr原子是分子磁矩的主要贡献者。晶胞体积变化时,各原子磁矩呈现不同的变化趋... 详细信息

利用基于密度泛函理论的第一性原理研究了黄铜矿CuCrS2的电子结构。结果表明:CuCrS2是一种半金属铁磁体,其半金属隙为0.18eV。每个CuCrS2分子的磁矩为3.00μB,Cr原子是分子磁矩的主要贡献者。晶胞体积变化时,各原子磁矩呈现不同的变化趋势,但Cr原子仍为分子磁矩的主要来源,晶胞体积增大5%和10%时,CuCrS2依然能表现出良好的半金属性。

关键词：第一性原理黄铜矿半金属性电子结构态密度

在线全文

学校读者我要写书评

暂无评论

脉冲强激光辐照下材料响应的非傅里叶效应

强激光与粒子束 2009年第6期21卷 808-812页

作者：黄海明孙岳北京交通大学工程力学研究所北京100044

研究了在多脉冲强激光辐照下靶材的热传导与热冲击特性。基于非傅里叶导热定律和热弹性理论,推导出多脉冲激光辐照下靶材温度场和热应力场的解析式;结合适当的边界条件,以不锈钢靶材为例,利用有限差分法和Matlab计算得到了多脉冲强激光... 详细信息

研究了在多脉冲强激光辐照下靶材的热传导与热冲击特性。基于非傅里叶导热定律和热弹性理论,推导出多脉冲激光辐照下靶材温度场和热应力场的解析式;结合适当的边界条件,以不锈钢靶材为例,利用有限差分法和Matlab计算得到了多脉冲强激光辐照下靶材内部过余温度随时间和深度演化情况以及内部热应力的演化规律。计算结果表明:多脉冲激光辐照下靶材热响应在离边界不同截面处温度波形变化出现延迟性,其滞后性能与弛豫时间有关;非傅里叶解中应力波的波前十分陡峭,具有明显的热冲击性。

关键词：激光辐照多脉冲激光非傅里叶效应热冲击