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Error modeling of 3-RSR parallel robot based on D-H transformation matrix 被引量:3
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作者 李瑞琴 杨斌 《Journal of Measurement Science and Instrumentation》 CAS 2014年第3期53-59,2,共7页
By selecting any one limb of 3-RSR parallel robot as a research object, the paper establishes a position and orienta- tion relationship matrix between the moving platform and the base by means of Denavit-Hartenberg (... By selecting any one limb of 3-RSR parallel robot as a research object, the paper establishes a position and orienta- tion relationship matrix between the moving platform and the base by means of Denavit-Hartenberg (D-H) transformation matrix. The error mapping model is derived from original error to the error of the platform by using matrix differential method. This model contains all geometric original errors of the robot. The nonlinear implicit function relation between po- sition and orientation error of the platform and the original geometric errors is simplified as a linear explicit function rela- tion. The results provide a basis for further studying error analysis and error compensation. 展开更多
关键词 error modeling 3-RSR parallel robot Denavit-Hartenberg (D-H) transformation matrix
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MODELING AND PERFORMANCE ANALYSIS FOR THE SERIAL AND PARALLEL PRODUCTION SYSTEM BASED ON GSPN 被引量:2
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作者 GaoJianhua HuXudong YangRuqing 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2004年第3期427-432,共6页
Differed from the existed applications of generalized stochastic Petri net(GSPN) theory in machine-tool manufacturing system, reliability computation of FMS, testabilityparameters determination and fault analysis, a n... Differed from the existed applications of generalized stochastic Petri net(GSPN) theory in machine-tool manufacturing system, reliability computation of FMS, testabilityparameters determination and fault analysis, a new idea of applying GSPN to model and performanceanalysis for the serial and parallel production system is proposed. And one typical discrete eventdynamic system (DEDS), turner-unit of palletizing system, is taken as a real case to research. Basedupon the established GSPN models, the working performances of serial and parallel layout arecompared. Furthermore, their differences of working mechanisms including feeding mechanism,coordinating mechanism and monitoring mechanism are discussed. Thus the theoretical basis which ishelpful to appraise layout plan and its reasonableness is provided. Meanwhile, the research resultsshow that parallel layout is more advantageous to greatly improve the operational speed ofproduction system than serial one. 展开更多
关键词 serial and parallel production system Generalized stochastic Petriv net Discrete event dynamic system Palletizing system
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3-PRS serial-parallel machine tool error calibration and parameter identification 被引量:2
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作者 ZHAO Jun-wei DAI Jun HUANG Jun-jie 《重庆邮电大学学报(自然科学版)》 北大核心 2009年第2期284-291,共8页
3-PRS serial-parallel machine tool consists of a 3-degree-of-freedom (DOF) implementation platform and a 2-DOF X-Y platform. The error modeling and parameter identification methods were deduced based on 3-PRS serial-p... 3-PRS serial-parallel machine tool consists of a 3-degree-of-freedom (DOF) implementation platform and a 2-DOF X-Y platform. The error modeling and parameter identification methods were deduced based on 3-PRS serial-parallel machine tool. 3-PRS serial-parallel machine tool was researched, and the mechanism of error analysis, modeling, identification of error parameters and measurement equipment for the use of agency error of measurement were conducted. In order to achieve the geometric parameters calibration and error compensation of the serial-parallel machine tool, the nominal structural parameters of the controller was adjusted by identifying the structure of the machine tool. With the establishment of a vector space size chain, we can do the error analysis, error modeling, error measurement and error compensation can be done. 展开更多
关键词 串并联机床 参数辨识 误差标定 串行 3自由度 误差建模 代理平台 结构参数
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Improved Hungarian algorithm for assignment problems of serial-parallel systems 被引量:5
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作者 Tingpeng Li Yue Li Yanling Qian 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第4期858-870,共13页
In order to overcome the shortcoming of the classical Hungarian algorithm that it can only solve the problems where the total cost is the sum of that of each job, an improved Hungarian algorithm is proposed and used t... In order to overcome the shortcoming of the classical Hungarian algorithm that it can only solve the problems where the total cost is the sum of that of each job, an improved Hungarian algorithm is proposed and used to solve the assignment problem of serial-parallel systems. First of all, by replacing parallel jobs with virtual jobs, the proposed algorithm converts the serial-parallel system into a pure serial system, where the classical Hungarian algorithm can be used to generate a temporal assignment plan via optimization. Afterwards, the assignment plan is validated by checking whether the virtual jobs can be realized by real jobs through local searching. If the assignment plan is not valid, the converted system will be adapted by adjusting the parameters of virtual jobs, and then be optimized again. Through iterative searching, the valid optimal assignment plan can eventually be obtained.To evaluate the proposed algorithm, the valid optimal assignment plan is applied to labor allocation of a manufacturing system which is a typical serial-parallel system. 展开更多
关键词 Hungarian algorithm assignment problem virtual job serial-parallel system optimization
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Research of 6-DOF Serial-Parallel Mechanism Platform for Stability Training of Legged-Walking Robot 被引量:1
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作者 Wei-Guo Wu Wen-Qian Du 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2014年第2期75-82,共8页
The concept of legged-robot stability training with a training platform is proposed and a serial-parallel mechanism platform with 6 degrees of freedom is designed for this target. The designed platform is composed of ... The concept of legged-robot stability training with a training platform is proposed and a serial-parallel mechanism platform with 6 degrees of freedom is designed for this target. The designed platform is composed of 4-DOF parallel mechanism with spherical joints and prismatic pairs,and 2-DOF serial mechanism with prismatic pairs. With this design,the platform has advantages of low platform countertop,big workspace,high carrying capacity and high stiffness. On the basis of DOF analysis and computation of space mechanism,weight supporting auxiliary mechanism and raceways-balls supporting mechanism are designed,so as to improve the stiffness of designed large platform and payload capacity of servo motors. And then the whole structure design work of the platform is done. Meanwhile,this paper derives the analytical solutions of forward kinematics, inverse kinematics and inverse dynamics. The error analysis model of position and orientation is established. And then the simulation is done in ADAMS to ensure the correctness and feasibility of this design. 展开更多
关键词 6-DOF serial-parallel mechanism forward kinematics stability training legged-walking robot
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FOPWA: An Optimized Parallel Algorithm of Watershed Transform for Image Segmentation 被引量:1
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作者 Haifang Zhou Xuejun Yang +1 位作者 Hengzhu Liu Yu rang 《通讯和计算机(中英文版)》 2006年第1期21-23,31,共4页
关键词 图像处理 信息转换 最优化预算法则 图像分割
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Parallel Computation of Fourier Transform on Distributed Memory Computer System
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作者 Yihui Yan Qingfeng Hu Xinfang He 《Wuhan University Journal of Natural Sciences》 CAS 1996年第Z1期557-560,共4页
Multicomputer systems(distributed memory computer systems) are becoming more and more popular and will be wildly used in scientific researches. In this paper, we present a parallel algorithm of Fourier Transform of a ... Multicomputer systems(distributed memory computer systems) are becoming more and more popular and will be wildly used in scientific researches. In this paper, we present a parallel algorithm of Fourier Transform of a vector of complex numbers on multicomputer system and give its computing times and its speedup in parallel environment supported by EXPRESS system on the multicomputer system which consists of four SGI workstations. Our analysis shows that the results is ideal and this scheme is suitable to multicomputer systems. 展开更多
关键词 Fourier transform Distributed Memory Computer System parallel Computing
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Experiments in Parallelizing the Type IV Discrete Cosine Transform
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《Computer Technology and Application》 2012年第4期305-314,共10页
The Fourier transform is very important to numerous applications in science and engineering. However, its usefulness is hampered by its computational expense. In this paper, in an attempt to develop a faster method fo... The Fourier transform is very important to numerous applications in science and engineering. However, its usefulness is hampered by its computational expense. In this paper, in an attempt to develop a faster method for computing Fourier transforms, the authors present parallel implementations of two new algorithms developed for the type IV Discrete Cosine Transform (DCT-IV) which support the new interleaved fast Fourier transform method. The authors discuss the realizations of their implementations using two paradigms. The first involved commodity equipment and the Message-Passing Interface (MPI) library. The second utilized the RapidMind development platform and the Cell Broadband Engine (BE) processor. These experiments indicate that the authors' rotation-based algorithm is preferable to their lifting-based algorithm on the platforms tested, with increased efficiency demonstrated by their MPI implementation for large data sets. Finally, the authors outline future work by discussing an architecture-oriented method for computing DCT-IVs which promises further optimization. The results indicate a promising fresh direction in the search for efficient ways to compute Fourier transforms. 展开更多
关键词 Discrete cosine transform parallel algorithms fast Fourier transforms ROTATION LIFTING MPI (message-passing interface) Cell BE (broadband engine).
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Optimization Parameter of Transformation of Parallel Translation for Ship Pitch Simulation
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作者 SHEN Ji-hongCollege of Science, Harbin Engineering University, Harbin 150001, China 《哈尔滨工程大学学报(英文版)》 2002年第2期33-36,共4页
The transformation of parallel translation can improve the smoothness of discrete series sometimes. In this paper, for ship pitch, a method to modify the system error is proposed via the transformation of parallel tra... The transformation of parallel translation can improve the smoothness of discrete series sometimes. In this paper, for ship pitch, a method to modify the system error is proposed via the transformation of parallel translation, which can give the optimize parameters using the Method of Minimum Squares. The series in the method can fit white exponential law better, and then be applied in GM (1,1) very well. The numerical experiments imply that the method is practical, which make the ship pitch system model more accurate than GM ( 1,1 ). 展开更多
关键词 wite EXPONENTIAL law the determination of parameters transformation of parallel TRANSLATION numerical computation SHIP PITCH simulation.
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PT-MIL:Parallel transformer based on multi-instance learning for osteoporosis detection in panoramic oral radiography
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作者 黄欣然 YANG Hongjie +2 位作者 CHEN Hu ZHANG Yi 廖培希 《中国体视学与图像分析》 2023年第4期410-418,共9页
Osteoporosis is a systemic disease characterized by low bone mass,impaired bone microstruc-ture,increased bone fragility,and a higher risk of fractures.It commonly affects postmenopausal women and the elderly.Orthopan... Osteoporosis is a systemic disease characterized by low bone mass,impaired bone microstruc-ture,increased bone fragility,and a higher risk of fractures.It commonly affects postmenopausal women and the elderly.Orthopantomography,also known as panoramic radiography,is a widely used imaging technique in dental examinations due to its low cost and easy accessibility.Previous studies have shown that the mandibular cortical index(MCI)derived from orthopantomography can serve as an important indicator of osteoporosis risk.To address this,this study proposes a parallel Transformer network based on multiple instance learning.By introducing parallel modules that alleviate optimization issues and integrating multiple-instance learning with the Transformer architecture,our model effectively extracts information from image patches.Our model achieves an accuracy of 86%and an AUC score of 0.963 on an osteoporosis dataset,which demonstrates its promising and competitive performance. 展开更多
关键词 parallel transformer multiple instance learning weakly-supervised classification
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基于改进的Swin Transformer的输油管道微小缺陷检测模型
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作者 姚睿 郎宪明 +2 位作者 袁开欣 侍殿超 张欣冉 《管道技术与设备》 CAS 2024年第3期35-42,47,共9页
针对磁漏微小缺陷检测困难、检测数据不足、检测精度低等问题,提出了去噪扩散概率模型(DDPM)-门控并行膨胀卷积的移位窗口变换器(DGPST)。文中引入了DDPM作为数据生成模型,获得高质量的数据样本。门控并行膨胀卷积的移位窗口变换器(GPST... 针对磁漏微小缺陷检测困难、检测数据不足、检测精度低等问题,提出了去噪扩散概率模型(DDPM)-门控并行膨胀卷积的移位窗口变换器(DGPST)。文中引入了DDPM作为数据生成模型,获得高质量的数据样本。门控并行膨胀卷积的移位窗口变换器(GPST)是在移位窗口变换器(Swin-Transformer)的基础上进行改进的。在GPST的主干网络中引入了门控并行膨胀卷积层,门控单元可以减少不必要的计算量,卷积提高了网络提取全局上下文信息的能力,有利于提高模型检测精度。实验结果表明:当IOU=0.5时,该算法的精确度为95.6%,推理时间(Latency)为8.2 ms。 展开更多
关键词 门控并行膨胀卷积 概率模型 移位窗口变换器 磁通量
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跨尺度跨维度的自适应Transformer网络应用于结直肠息肉分割 被引量:2
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作者 梁礼明 何安军 +1 位作者 李仁杰 吴健 《光学精密工程》 EI CAS CSCD 北大核心 2023年第18期2700-2712,共13页
针对结直肠息肉图像病灶区域尺度变化大、边界模糊、形状不规则且与正常组织对比度低等问题,导致边缘细节信息丢失和病灶区域误分割,提出一种跨尺度跨维度的自适应Transformer分割网络。该网络一是利用Transformer编码器建模输入图像的... 针对结直肠息肉图像病灶区域尺度变化大、边界模糊、形状不规则且与正常组织对比度低等问题,导致边缘细节信息丢失和病灶区域误分割,提出一种跨尺度跨维度的自适应Transformer分割网络。该网络一是利用Transformer编码器建模输入图像的全局上下文信息,多尺度分析结直肠息肉病灶区域。二是通过通道注意力桥和空间注意力桥减少通道维度冗余和增强模型空间感知能力,抑制背景噪声。三是采用多尺度密集并行解码模块来填补各层跨尺度特征信息之间的语义空白,有效聚合多尺度上下文特征。四是设计面向边缘细节的多尺度预测模块,以可学习的方式引导网络去纠正边界错误预测分类。在CVC-ClinicDB、Kvasir-SEG、CVC-ColonDB和ETIS数据集上进行实验,其Dice相似性系数分别为0.942,0.932,0.811和0.805,平均交并比分别为0.896,0.883,0.731和0.729,其分割性能优于现有方法。仿真实验表明,本文方法能有效改善结直肠息肉病灶区域误分割,具有较高的分割精度,为结直肠息肉诊断提供新窗口。 展开更多
关键词 结直肠息肉 transformER 多尺度密集并行解码模块 多尺度预测模块
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多尺度可变形Transformer纸币序列号识别
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作者 张开生 李旭洋 《计算机工程与应用》 CSCD 北大核心 2023年第18期105-118,共14页
纸币序列号识别系统在纸币流通的监管中扮演着重要角色,而纸币在实际使用的过程中会产生变形或受到污染导致纸币序列号呈现出不规则文本的特点。为满足不规则纸币序列号的识别需求,提出基于多尺度可变形Transformer的纸币序列号的识别... 纸币序列号识别系统在纸币流通的监管中扮演着重要角色,而纸币在实际使用的过程中会产生变形或受到污染导致纸币序列号呈现出不规则文本的特点。为满足不规则纸币序列号的识别需求,提出基于多尺度可变形Transformer的纸币序列号的识别方法。通过自主搭建的纸币序列号检测平台获取纸币序列号图像传输至计算机。序列号图像通过骨干网络提取特征图并传输至编码器,通过多尺度可变形注意力机制进一步提取文本的多尺度特征信息,随后采用多边形边界框检测机制,经候选框生成器提取文本的粗边界框,引导位置解码器中的多边形边界框坐标的回归训练,字符解码器在位置解码器预测文本边界框的同时进行字符预测,最终输出纸币序列号文本识别结果。实验结果表明,该方法能够满足纸币序列号在线检测与识别的需求。 展开更多
关键词 纸币序列号 深度学习 transformER 字符识别
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融合Swin-Transformer网络模型的水体高光区域提取 被引量:2
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作者 陈毅夫 何敬 +1 位作者 刘刚 毛佳琪 《遥感信息》 CSCD 北大核心 2023年第4期129-136,共8页
在强光的照射下,水体的镜面反射往往会对遥感影像产生很大影响,其主要表现就是在图像上产生大小不同、形状各异的亮斑。这些亮斑附近的地物信息基本上都被淹没,对后期的影像分析会造成不同程度的影响,因此对这些亮斑的检测识别就显得尤... 在强光的照射下,水体的镜面反射往往会对遥感影像产生很大影响,其主要表现就是在图像上产生大小不同、形状各异的亮斑。这些亮斑附近的地物信息基本上都被淹没,对后期的影像分析会造成不同程度的影响,因此对这些亮斑的检测识别就显得尤为重要。文章以DeeplabV3plus为主要网络,提出一种融合Swin-Transformer模块的网络模型。该模型将Swin-Transformer网络作为一个模块与卷积骨干网络并行提取特征。提取出的两类特征经上采样后进行特征融合,再经多次卷积等实现了水体亮斑的识别与分割。实验结果表明,该模型能够对不同类型、不同形状的水体亮斑进行识别分割,其平均交并比为93.44%。 展开更多
关键词 水体高光区域提取 Swin-transformer DeeplabV3plus 特征并行提取 特征融合
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Reconstruction method of irregular seismic data with adaptive thresholds based on different sparse transform bases 被引量:3
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作者 Zhao Hu Yang Tun +4 位作者 Ni Yu-Dong Liu Xing-Gang Xu Yin-Po Zhang Yi-Lei Zhang Guang-Rong 《Applied Geophysics》 SCIE CSCD 2021年第3期345-360,432,共17页
Oil and gas seismic exploration have to adopt irregular seismic acquisition due to the increasingly complex exploration conditions to adapt to complex geological conditions and environments.However,the irregular seism... Oil and gas seismic exploration have to adopt irregular seismic acquisition due to the increasingly complex exploration conditions to adapt to complex geological conditions and environments.However,the irregular seismic acquisition is accompanied by the lack of acquisition data,which requires high-precision regularization.The sparse signal feature in the transform domain in compressed sensing theory is used in this paper to recover the missing signal,involving sparse transform base optimization and threshold modeling.First,this paper analyzes and compares the effects of six sparse transformation bases on the reconstruction accuracy and efficiency of irregular seismic data and establishes the quantitative relationship between sparse transformation and reconstruction accuracy and efficiency.Second,an adaptive threshold modeling method based on sparse coefficient is provided to improve the reconstruction accuracy.Test results show that the method has good adaptability to different seismic data and sparse transform bases.The f-x domain reconstruction method of effective frequency samples is studied to address the problem of low computational efficiency.The parallel computing strategy of curvelet transform combined with OpenMP is further proposed,which substantially improves the computational efficiency under the premise of ensuring the reconstruction accuracy.Finally,the actual acquisition data are used to verify the proposed method.The results indicate that the proposed method strategy can solve the regularization problem of irregular seismic data in production and improve the imaging quality of the target layer economically and efficiently. 展开更多
关键词 irregular acquisition seismic data reconstruction adaptive threshold f-x domain OpenMP parallel optimization sparse transformation
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Using redundant parallel architecture to improve speaker recognition performance 被引量:1
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作者 Zhengquan QIU Junxun YIN Caiyun FAN 《控制理论与应用(英文版)》 EI 2008年第2期221-223,共3页
In this paper, we propose two kinds of modifications in speaker recognition. First, the correlations between frequency channels are of prime importance for speaker recognition. Some of these correlations are lost when... In this paper, we propose two kinds of modifications in speaker recognition. First, the correlations between frequency channels are of prime importance for speaker recognition. Some of these correlations are lost when the frequency domain is divided into sub-bands. Consequently we propose a particularly redundant parallel architecture for which most of the correlations are kept. Second, generally a log transformation used to modify the power spectrum is done after the filter-bank in the classical spectrum calculation. We will see that performing this transformation before the filter bank is more interesting in our case. In the processing of recognition, the Gaussian mixture model (GMM) recognition arithmetic is adopted. Experiments on speech corrupted by noise show a better adaptability of this approach in noisy environments, comoared with a conventional device, esoeciallv when oruning of some recognizers is performed. 展开更多
关键词 CORRELATIONS Redundant parallel architecture Log transformation GMM
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An Approach to Parallelization of SIFT Algorithm on GPUs for Real-Time Applications 被引量:4
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作者 Raghu Raj Prasanna Kumar Suresh Muknahallipatna John McInroy 《Journal of Computer and Communications》 2016年第17期18-50,共33页
Scale Invariant Feature Transform (SIFT) algorithm is a widely used computer vision algorithm that detects and extracts local feature descriptors from images. SIFT is computationally intensive, making it infeasible fo... Scale Invariant Feature Transform (SIFT) algorithm is a widely used computer vision algorithm that detects and extracts local feature descriptors from images. SIFT is computationally intensive, making it infeasible for single threaded im-plementation to extract local feature descriptors for high-resolution images in real time. In this paper, an approach to parallelization of the SIFT algorithm is demonstrated using NVIDIA’s Graphics Processing Unit (GPU). The parallel-ization design for SIFT on GPUs is divided into two stages, a) Algorithm de-sign-generic design strategies which focuses on data and b) Implementation de-sign-architecture specific design strategies which focuses on optimally using GPU resources for maximum occupancy. Increasing memory latency hiding, eliminating branches and data blocking achieve a significant decrease in aver-age computational time. Furthermore, it is observed via Paraver tools that our approach to parallelization while optimizing for maximum occupancy allows GPU to execute memory bound SIFT algorithm at optimal levels. 展开更多
关键词 Scale Invariant Feature transform (SIFT) parallel Computing GPU GPU Occupancy Portable parallel Programming CUDA
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A Matrix Formulation of Discrete Chirp Fourier Transform Algorithms 被引量:1
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作者 Juan Pablo Soto Quiros Domingo Rodriguez 《Journal of Electronic Science and Technology》 CAS 2014年第2期206-210,共5页
This work presents a computational matrix framework in terms of tensor signal algebra for the formulation of discrete chirp Fourier transform algorithms. These algorithms are used in this work to estimate the point ta... This work presents a computational matrix framework in terms of tensor signal algebra for the formulation of discrete chirp Fourier transform algorithms. These algorithms are used in this work to estimate the point target functions (impulse response functions) of multiple-input multiple-output (MIMO) synthetic aperture radar (SAR) systems. This estimation technique is being studied as an alternative to the estimation of point target functions using the discrete cross-ambiguity function for certain types of environmental surveillance applications. The tensor signal algebra is presented as a mathematics environment composed of signal spaces, finite dimensional linear operators, and special matrices where algebraic methods are used to generate these signal transforms as computational estimators. Also, the tensor signal algebra contributes to analysis, design, and implementation of parallel algorithms. An instantiation of the framework was performed by using the MATLAB Parallel Computing Toolbox, where all the algorithms presented in this paper were implemented. 展开更多
关键词 Discrete chirp Fourier transform MATLAB parallel computing tensor signal algebra
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Run-Up Flow of a Maxwell Fluid through a Parallel Plate Channel 被引量:1
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作者 Syed Yedulla Qadri M. Veera Krishna 《American Journal of Computational Mathematics》 2013年第4期297-303,共7页
We consider the flow of an incompressible viscous Maxwell fluid between two parallel plates, initially induced by a constant pressure gradient. The pressure gradient is withdrawn and the upper plate moves with a unifo... We consider the flow of an incompressible viscous Maxwell fluid between two parallel plates, initially induced by a constant pressure gradient. The pressure gradient is withdrawn and the upper plate moves with a uniform velocity while the lower plate continues to be at rest. The arising flow is referred to as run-up flow. The unsteady governing equations are solved as initial value problem using Laplace transform technique. The expression for velocity, shear stresses on both plates and discharge are obtained. The behavior of the velocity, shear stresses and mass flux has been discussed in detail with respect to variations in different governing flow parameters and is presented through graphs. 展开更多
关键词 RUN-UP FLOW Maxwell’s Fluid LAPLACE transforms REYNOLDS Number and parallel PLATE CHANNELS
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Stiffness Analysis of Spherical Parallel Mechanism U_(P+R) with 2-DOF
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作者 Yu-Lin Zhou Long Yang +2 位作者 Bo Li Da-Xing Zeng Feng Gao 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2013年第4期41-47,共7页
As one of the typical less-mobility parallel mechanisms, the spherical parallel mechanism Up.s with two degrees of freedom (2-DOF) possess high order overconstraints, and the calculation of its stiffness is partly d... As one of the typical less-mobility parallel mechanisms, the spherical parallel mechanism Up.s with two degrees of freedom (2-DOF) possess high order overconstraints, and the calculation of its stiffness is partly different with general parallel mechanisms owing to the bars in each branch are assumed to be arc-shaped. By means of small deformation superposition principle, the relationship between the angle displacement and line displacement of moving platform and the forces acted on the branches were derived out. Based on the results of static analysis, the relationship between the applied force, the line displacement and the angle displacement of the mechanism was set up. And then the stiffness matrix was obtained. The six principal stiffness of the mechanism and the corresponding directions were achieved by the orthogonal transformation. The numerical calculation was performed and the results showed that the principal stiffness and directions are varied with the pose-position of the mechanism, and the principal stiffness is gradually enlarged when it is far away from the anigin. In addition, the torsion stiffness is much greater and the line deformation stiffness is smaller, the difference between the two parts is huge. The research content of this paper supplies the theoretical foundation for the further engineering design and application of the spherical parallel mechanism. 展开更多
关键词 spherical parallel mechanism static stiffness orthogonal transformation line displacement ANGLE
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