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Landscape Space Construction Based on Motion Vision——A Case Study of Landscape Design of Sichuan Olympic Sports School in China
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作者 冯美文 孙大江 杨铱 《Journal of Landscape Research》 2011年第9期1-6,共6页
After the analysis of the beauty contained in motion vision, the paper had pointed out that motion vision was the link for spectators relating and communicating with aesthetic objects and decided landscape space const... After the analysis of the beauty contained in motion vision, the paper had pointed out that motion vision was the link for spectators relating and communicating with aesthetic objects and decided landscape space construction sequence. It further analyzed the relations between architectural space and visual perception which could be divided into inner experience and external experience. By taking landscape space construction of Sichuan Olympic Sports School for example, based on the analysis of design principles and objective of landscape space, the paper had focused on the discussion of landscape concept in terms of motion vision. In the perspective of two-dimensional vision, landscape effects of White Pigeon Square and Bright Eyes Square had been introduced. In the perspective of three-dimensional vision, landscape effects of the Olympic Rings waterscape and the Olympic Rings gallery had been illustrated. Finally, based on the integration between landscapes and architectures under visual perception, the coordination between campus architectures and landscape construction in Olympic Sports School had been analyzed. 展开更多
关键词 motion VISION LANDSCAPE space OLYMPIC SPORTS SCHOOL LANDSCAPE design
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Restoration of space-variant blurred image based on motion-blurred target segmentation 被引量:4
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作者 Yuye Zhang Xuewei Wang Chunxin Wang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第2期191-196,共6页
In imaging on moving target, it is easy to get space- variant blurred image. In order to recover the image and gain recognizable target, an approach to recover the space-variant blurred image is presented based on ima... In imaging on moving target, it is easy to get space- variant blurred image. In order to recover the image and gain recognizable target, an approach to recover the space-variant blurred image is presented based on image segmentation. Be- cause of motion blur's convolution process, the pixels of observed image's target and background will be displaced and piled up to produce two superposition regions. As a result, the neighbor- ing pixels in the superposition regions will have similar grey level change. According to the pixel's motion-blur character, the target's blurred edge of superposition region could be detected. Canny operator can be recurred to detect the target edge which parallels the motion blur direction. Then in the segmentation process, the whole target image which has the character of integral convolution between motion blur and real target image can be obtained. At last, the target image is restored by deconvolution algorithms with adding zeros. The restoration result indicates that the approach can effectively solve the kind of problem of space-variant motion blurred image restoration. 展开更多
关键词 image restoration space-variant blur image segmen- tation motion-blur.
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BASED ON WAVELET ANALYSIS TO OPTIMAL CONTROL OF MOTION PLANNING OF SPACE MANIPULATOR
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作者 戈新生 张奇志 刘延柱 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2000年第10期1161-1168,共8页
The optimal control problem of nonholonomic motion planning of space manipulator was discussed. Utilizing the method of wavelet analysis, the discrete orthogonal wavelets were introduced to solve the optimal control p... The optimal control problem of nonholonomic motion planning of space manipulator was discussed. Utilizing the method of wavelet analysis, the discrete orthogonal wavelets were introduced to solve the optimal control problem, the classical Fourier basic functions were replaced by the wavelet expansion approximation. A numerical algorithm of optimal control was proposed based an wavelet analysis. The numerical simulation shows, the method is effective for nonholonomic motion planning of space manipulator. 展开更多
关键词 space manipulator motion planning optimal control wavelet analysis
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THE HOMOTHETIC MOTIONS IN THE LORENTZ 3-SPACE
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作者 M.Tosun A.Kucuk M.A.Gungor 《Acta Mathematica Scientia》 SCIE CSCD 2006年第4期711-719,共9页
In this article, the properties of the homothetic motions in three-dimensional Lorentz space are investigated. Also, some geometric results between velocity and acceleration vectors of a point in a spatial motion are ... In this article, the properties of the homothetic motions in three-dimensional Lorentz space are investigated. Also, some geometric results between velocity and acceleration vectors of a point in a spatial motion are obtained. 展开更多
关键词 Homothetic motion space kinematics Lorentzian geometry
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Far-field analysis of effects of unilateral rupturing fault on the space correlation of strong ground motion
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作者 金星 陈超 +1 位作者 张明宇 高孟潭 《Acta Seismologica Sinica(English Edition)》 EI CSCD 2000年第5期544-551,共8页
On the assumption that seismic source is simplified as linear rupture fault with finite length, this paper qualitatively studies the seismic source effects on space correlation of strong ground motion. Based on expand... On the assumption that seismic source is simplified as linear rupture fault with finite length, this paper qualitatively studies the seismic source effects on space correlation of strong ground motion. Based on expanding expression of Fourier spectrum of strong ground motion with space coordinate variables, this paper also gives a expression of describing correlation of strong ground motion field. According to far-field condition, the theoretical formula of the expression can be obtained. Furthermore, this paper presents a theoretical formula of estimation the radius of strong ground motion field, which depends on expansion condition of Fourier spectrum of strong ground motion, with space variables. At last, taking one earthquake as an example, this paper gives three-dimension patterns of radius of the field with epicenter distance and azimuth as well as frequency. 展开更多
关键词 one-direction rupture fault strong ground motion space correlation FAR-FIELD
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Measurement of the secular motion frequency and the space charge density in the linear ion trap
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作者 周飞 谢艺 +2 位作者 徐酉阳 黄学人 冯芒 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第11期294-300,共7页
This paper reports that a cloud of laser-cooled ^40Ca^+ is successfully trapped and manipulated in the home-built linear ion trap constructed for quantum information processing (QIP). The frequency of the secular m... This paper reports that a cloud of laser-cooled ^40Ca^+ is successfully trapped and manipulated in the home-built linear ion trap constructed for quantum information processing (QIP). The frequency of the secular motion and the space charge density of the ion cloud are measured, which help knowing the characteristic of the trapping potential and are the prerequisite of QIP with the trapped ions. 展开更多
关键词 trapped ions secular motion frequency space charge
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Extension of Motion Space for Double-Screw-Drive Bending Mechanism
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作者 Chiharu Ishii 《通讯和计算机(中英文版)》 2012年第5期507-515,共9页
关键词 运动空间 双螺杆 驱动器 机制 弯曲 方程推导 运动学问题 软件分析
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Motion of a Nonrelativistic Quantum Particle in Non-commutative Phase Space
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作者 FATEME Hoseini 马凯 HASSAN Hassanabadi 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第10期5-8,共4页
The equation governing the motion of a quantum particle is considered in nonrelativistic non-commutative phase space. For this aim, we first study new Poisson brackets in non-commutative phase space and obtain the mod... The equation governing the motion of a quantum particle is considered in nonrelativistic non-commutative phase space. For this aim, we first study new Poisson brackets in non-commutative phase space and obtain the modified equations of motion. Next, using novel transformations, we solve the equation of motion and report the exact analytical solutions. 展开更多
关键词 motion of a Nonrelativistic Quantum Particle in Non-commutative Phase space NCS
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RELATIVE MOTION AND DEFORMATION OF PACIFIC PLATE FROM SPACE GEODESY
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作者 Jin Shuanggen and Zhu Wenyao (Shanghai Astronomical Observatory, CAS, Shanghai 200030, China) 《大地测量与地球动力学》 CSCD 2003年第B12期50-53,61,共5页
The circum Pacific tectonic system that contains of convergent, divergent and transform boundaries, is the most active region of volcanoes and earthquakes in the world, and involves many important theoretical question... The circum Pacific tectonic system that contains of convergent, divergent and transform boundaries, is the most active region of volcanoes and earthquakes in the world, and involves many important theoretical questions in geosciences. The relative motion and deformation of Pacific plate is still an active subject of research. In this note, we analyze the deformation of Pacific plate and obtain reliable results of the relative motion rates at the circum Pacific boundaries based on space geodetic data, which reveals the present day motion characteristics of Pacific plate. 展开更多
关键词 空间地球测量 欧拉矢量 太平洋板块 相对运动 环太平洋的边缘
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Terminal sliding mode control for coordinated motion of a space rigid manipulator with external disturbance 被引量:3
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作者 郭益深 陈力 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2008年第5期583-590,共8页
The control problem of coordinated motion of a free-floating space rigid manipulator with external disturbance is discussed. By combining linear momentum conversion and the Lagrangian approach, the full-control dynami... The control problem of coordinated motion of a free-floating space rigid manipulator with external disturbance is discussed. By combining linear momentum conversion and the Lagrangian approach, the full-control dynamic equation and the Jacobian relation of a free-floating space rigid manipulator are established and then inverted to the state equation for control design. Based on the terminal sliding mode control (SMC) technique, a mathematical expression of the terminal sliding surface is proposed. The terminal SMC scheme is then developed for coordinated motion between the base's attitude and the end-effector of the free-floating space manipulator with external disturbance. This proposed control scheme not only guarantees the existence of the sliding phase of the closed-loop system, but also ensures that the output tracking error converges to zero in finite time. In addition, because the initial system state is always at the terminal sliding surface, the control scheme can eliminate reaching phase of the SMC and guarantee global robustness and stability of the closed-loop system. A planar free-floating space rigid manipulator is simulated to verify the feasibility of the proposed control scheme. 展开更多
关键词 free-floating space rigid manipulator external disturbance terminal slidingsurface coordinated motion terminal sliding mode control
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Motion Planning for Minimizing Base Disturbance of Space Manipulators
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作者 纪路 周东生 张强 《Journal of Donghua University(English Edition)》 EI CAS 2015年第2期252-256,共5页
A simulated annealing particle swarm optimization(PSO)algorithm is utilized in this paper to plan the motion of space manipulators with minimized base disturbance,not only its attitude but also its position.Since spac... A simulated annealing particle swarm optimization(PSO)algorithm is utilized in this paper to plan the motion of space manipulators with minimized base disturbance,not only its attitude but also its position.Since space manipulators must meet the Law of Momentum Conservation,any motion of manipulators will disturb the spacecraft which is free-float in the space environment.This paper tries to limit this effect to the minimum.First,this paper establishes the mathematical model for space manipulators by generalized Jacobian matrix(GJM) and analyzes its inverse kinematics by Theory of Screws.Second,a polynomial function of seventh degree is used to parameterize the joint motion and quaternion representation is also used to represent attitude of spacecraft.Moreover,this paper designs a proper objective function and depicts this algorithm detailedly and clearly.Finally,the results of numerical simulation are verified by the proposed algorithm. 展开更多
关键词 utilized kinematics verified disturbance inverse annealing attitude polynomial effector spacecraft
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环形桁架式空间薄膜展开机构运动精度可靠性建模与分析 被引量:1
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作者 尹大勇 胡明 +2 位作者 孟少华 高云 吴梅 《航天器环境工程》 CSCD 2024年第1期34-42,共9页
空间薄膜展开机构的姿态和位置精度会对薄膜索网的工作形态产生影响。文章首先构建环形桁架式空间薄膜展开机构运动精度可靠性理论模型,然后基于ADAMS建立考虑展开机构杆长误差的参数化仿真模型,并采用蒙特卡罗法对展开机构进行运动精... 空间薄膜展开机构的姿态和位置精度会对薄膜索网的工作形态产生影响。文章首先构建环形桁架式空间薄膜展开机构运动精度可靠性理论模型,然后基于ADAMS建立考虑展开机构杆长误差的参数化仿真模型,并采用蒙特卡罗法对展开机构进行运动精度可靠性仿真分析,求解运动精度可靠度。结果表明,以机构展开到位时折展杆支撑点所拟合的空间圆心坐标位置误差及半径误差作为其运动精度可靠性量化评价指标是正确的。该研究可为空间薄膜展开机构的可靠性设计提供参考。 展开更多
关键词 环形桁架 空间薄膜展开机构 运动精度可靠性 可靠性建模 可靠性仿真
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基于映射空间编码的高速运动轨道图像去模糊研究 被引量:1
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作者 鄢化彪 刘词波 +1 位作者 黄绿娥 赵恒 《铁道科学与工程学报》 EI CAS CSCD 北大核心 2024年第2期812-825,共14页
针对轨道缺陷检测系统因镜头抖动或相机快速移动而导致所采集图像较为模糊的问题,提出一种基于最大后验概率估计思想的映射空间编码的高速运动轨道图像去模糊算法。首先,该算法使用深度编解码器和残差网络分别对数据集中清晰图像到模糊... 针对轨道缺陷检测系统因镜头抖动或相机快速移动而导致所采集图像较为模糊的问题,提出一种基于最大后验概率估计思想的映射空间编码的高速运动轨道图像去模糊算法。首先,该算法使用深度编解码器和残差网络分别对数据集中清晰图像到模糊图像的映射关系和模糊核进行编码,为了保证编码时频率信息的完整性,算法在传统的残差模块上引入快速傅里叶变换通道构成双通道残差网络,以补偿多次特征提取带来的频率损失;其次,算法采用深度图像先验(Deep Image Prior,DIP)将潜在的清晰图像和模糊核进行参数化,再利用先验得到的模糊核和清晰图像来调用编码空间中的映射关系;最后,通过交替优化潜在的清晰图像和模糊核,从而去逼近一个真实未知的映射,进而实现真实场景下高速运动轨道图像的去模糊。实验结果表明,双通道残差模块提取的特征图频率信息分量强度普遍高于传统的残差模块,相较于使用传统残差模块实现该算法,采用双通道残差模块可使峰值信噪比(Peak Signal-to-Noise Ratio,PSNR)提升0.84 dB,结构相似性(Structural Similarity,SSIM)提高0.025 1。与现有的深度学习去模糊算法相比,提出的去模糊算法对高速轨道检测系统所采集图像的去模糊效果更佳,在性能方面相较于最好的去模糊算法,PSNR提高了1.84 dB,SSIM提升了0.017 3,显著提升了采集图像的质量。研究结果可为下一步识别轨道部件是否存在缺陷提供清晰图像。 展开更多
关键词 运动去模糊 编码-解码器 映射空间 深度图像先验 残差网络
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Talmy认知语义学的理论、实践和发展——体认语义学刍议(之二)
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作者 王寅 《天津外国语大学学报》 2024年第1期44-52,111-112,共11页
Talmy的两卷本《认知语义学》对该学科作出了重要贡献,旨在动态性建构人类的概念体系,但书中论述的五大图式系统存在不合理之处。文章分析了空间和运动图式系统及其具体应用,包括英语空间介词的直观性体认教学方法,基于体认观简析三个... Talmy的两卷本《认知语义学》对该学科作出了重要贡献,旨在动态性建构人类的概念体系,但书中论述的五大图式系统存在不合理之处。文章分析了空间和运动图式系统及其具体应用,包括英语空间介词的直观性体认教学方法,基于体认观简析三个最基本介词at,on,in的原型意义和用法,以及介词如何用于开启运动事件的焦点窗,指出英语中表示方向、路径的前缀可与动作词根融合成词。因此,运动动词可有两类不同的路径卫星,是对Talmy区分卫星框架语和动词框架语的一个补充。 展开更多
关键词 认知语义学 空间与运动 体认语义学
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Coordinated motion planning algorithm for multi-arm free flying space robot system
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作者 何光彩 洪炳熔 柳长安 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1999年第4期42-45,共4页
The motion planning problem of a free flying space robot (FFSR) is investigated and from the attitude disturbance characteristics of a multi arm FFSR, a new method based on the fixed attitude restricted (FAR) Gene... The motion planning problem of a free flying space robot (FFSR) is investigated and from the attitude disturbance characteristics of a multi arm FFSR, a new method based on the fixed attitude restricted (FAR) Generalized Jacobian Matrix of a multi arm FFSR is proposed to enable the coordinated motion of all the other arms while one arm is tracing a given path so that there is no disturbance on the body, and the problem of attitude disturbance with an operating multi arm FFSR is thereby better resolved. The simulation run with a dual arm FFSR system verifies the effectiveness of this algorithm. 展开更多
关键词 free FLYING space robot fixed ATTITUDE restricted (FAR) Generalized JACOBIAN Matrix motionS planning ATTITUDE control
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侧面爆破粉尘时空分布模拟分析
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作者 石零 姚芮 +4 位作者 严佳宁 罗开阳 常玉锋 安良 胡明华 《工业安全与环保》 2024年第7期90-93,共4页
从开放性细颗粒物污染治理角度出发,建立建筑物拆除爆破产尘的几何计算模型,运用计算流体力学(CFD)工具,对给定环境风速下的建筑物周围压力场和速度场进行了模拟分析,并对侧面折叠爆破粉尘按R-R(Rosin-Rammler)分布,使用气流-粒子双向... 从开放性细颗粒物污染治理角度出发,建立建筑物拆除爆破产尘的几何计算模型,运用计算流体力学(CFD)工具,对给定环境风速下的建筑物周围压力场和速度场进行了模拟分析,并对侧面折叠爆破粉尘按R-R(Rosin-Rammler)分布,使用气流-粒子双向耦合的DPM模型研究了爆炸粉尘的时空分布。结果表明,下风侧因建筑物存在导致风速、压力急剧变化而产生涡流,涡流是影响爆破粉尘时空分布的关键因素之一。在时间上,爆破粉尘有气流拖曳运动状态和扩散态;在空间上,因重力作用致下部空间的粉尘浓度较大。 展开更多
关键词 爆破粉尘时空分布 运动分析 开放性爆尘 空气污染治理
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一种联合TDCM和PFA的空间目标大转角ISAR成像方法 被引量:1
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作者 胡国伟 汪玲 朱岱寅 《雷达科学与技术》 北大核心 2024年第2期161-169,共9页
空间目标态势感知是当前航天技术领域的研究热点,逆合成孔径雷达(Inverse Synthetic Aperture Radar, ISAR)是空间目标感知的一种有效手段。为了得到利于目标鉴别的高分辨二维ISAR图像,需要通过增大积累转角来提高方位向分辨率。但是,... 空间目标态势感知是当前航天技术领域的研究热点,逆合成孔径雷达(Inverse Synthetic Aperture Radar, ISAR)是空间目标感知的一种有效手段。为了得到利于目标鉴别的高分辨二维ISAR图像,需要通过增大积累转角来提高方位向分辨率。但是,随着转角的增大,平动与转动之间的耦合增大,使得传统的先平动补偿、后利用转动成像的两步式成像方法不再适用。本文提出了一种结合时域信号共轭相乘(Time Domain Conjugate Multiplication, TDCM)处理与极坐标格式算法(Polar Format Algorithm, PFA)的成像算法,首先利用雷达回波的二维相干性,通过TDCM处理进行平动粗补偿,然后借助PFA的插值操作校正大转角引起的散射点越分辨单元走动(Motion Through Resolution Cell, MTRC)并估计目标相对转动参数。通过迭代处理,持续对平动和转动参数进行优化,提升运动补偿效果。仿真验证了所提成像算法的有效性,与传统算法相比,成像聚焦性更好。 展开更多
关键词 逆合成孔径雷达 空间目标 大转角 运动补偿
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多参数MRI联合临床危险因素术前预测直肠癌淋巴血管间隙侵犯的应用价值
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作者 章锦伟 朱浩雨 +2 位作者 刘啸峰 黄述斌 董江宁 《安徽医学》 2024年第6期694-700,共7页
目的探讨多参数MRI联合临床危险因素术前预测直肠癌淋巴血管间隙侵犯(LSVI)的价值。方法回顾性分析池州市人民医院2022年4月至2023年11月经术后病理证实的38例直肠癌患者的临床及影像学资料,所有患者均行常规MRI、合成MRI及IVIM-DWI序... 目的探讨多参数MRI联合临床危险因素术前预测直肠癌淋巴血管间隙侵犯(LSVI)的价值。方法回顾性分析池州市人民医院2022年4月至2023年11月经术后病理证实的38例直肠癌患者的临床及影像学资料,所有患者均行常规MRI、合成MRI及IVIM-DWI序列扫描。依据术后病理结果分为LVSI阳性组(n=14)和LVSI阴性组(n=24)。采用单因素和多因素logistic回归分析LVSI阳性组和LVSI阴性组的临床资料,分析LVSI的临床危险因素;比较两组患者合成MRI(T1值、T2值、PD值)及IVIM-DWI参数(D值、D*值、f值),采用受试者工作特征(ROC)曲线评价各定量参数预测模型及联合临床危险因素预测模型的诊断效能。结果合成MRI的T2值及IVIM-DWI的D值、f值在直肠癌LVSI阳性组和阴性组中比较差异具有统计学意义(P<0.05)。术前CEA(OR=10.818,95%CI:1.391~84.124)及临床N分期(OR=11.852,95%CI:1.534~91.552)是直肠癌LVSI的独立危险因素(P<0.05)。单独的T2值、D值、f值及三者联合的曲线下面积(AUC)分别为0.801、0.747、0.766、0.807,联合临床危险因素的预测模型效能最高(AUC=0.845),灵敏度为78.58%,特异度为100%。结论多参数MRI术前可有效预测直肠癌LVSI的状态,结合临床危险因素的联合预测模型可进一步提升预测效能,有助于临床医师制定个性化直肠癌治疗方案。 展开更多
关键词 直肠癌 淋巴血管间隙侵犯 合成磁共振成像 体素内不相干运动扩散加权成像
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Adaptive neural network control for coordinated motion of a dual-arm space robot system with uncertain parameters
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作者 郭益深 陈力 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2008年第9期1131-1140,共10页
Control of coordinated motion between the base attitude and the arm joints of a free-floating dual-arm space robot with uncertain parameters is discussed. By combining the relation of system linear momentum conversati... Control of coordinated motion between the base attitude and the arm joints of a free-floating dual-arm space robot with uncertain parameters is discussed. By combining the relation of system linear momentum conversation with the Lagrangian approach, the dynamic equation of a robot is established. Based on the above results, the free-floating dual-arm space robot system is modeled with RBF neural networks, the GL matrix and its product operator. With all uncertain inertial system parameters, an adaptive RBF neural network control scheme is developed for coordinated motion between the base attitude and the arm joints. The proposed scheme does not need linear parameterization of the dynamic equation of the system and any accurate prior-knowledge of the actual inertial parameters. Also it does not need to train the neural network offline so that it would present real-time and online applications. A planar free-floating dual-arm space robot is simulated to show feasibility of the proposed scheme. 展开更多
关键词 flee-floating dual-arm space robot RBF neural network GL matrix andits product operator coordinated motion adaptive control
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空间运动刚体加速度瞬轴位置的分析
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作者 樊薇 卢其宜 《科学技术创新》 2024年第16期50-53,共4页
针对空间运动刚体的加速度分析,本文提出了在各种情况下确定空间运动刚体加速度瞬轴(或动轴)位置的方法。研究结果表明,对于空间运动的刚体,当角速度矢与角加速度矢平行时,存在加速度瞬轴(或动轴),此时,刚体可视为绕加速度瞬轴(或动轴)... 针对空间运动刚体的加速度分析,本文提出了在各种情况下确定空间运动刚体加速度瞬轴(或动轴)位置的方法。研究结果表明,对于空间运动的刚体,当角速度矢与角加速度矢平行时,存在加速度瞬轴(或动轴),此时,刚体可视为绕加速度瞬轴(或动轴)作转动,即用加速度瞬轴(或动轴)法求解刚体上任一点的加速度。用这种方法分析空间运动刚体上各点加速度的时候更加方便快捷。 展开更多
关键词 空间运动 加速度瞬轴 加速度动轴 轴向加速度投影定理
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