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HERMITE—BIRKHOFF INTERPOLATION OF SCATTERED DATA BY RADIAL BASIS FUNCTIONS 被引量:5
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作者 吴宗敏 《Analysis in Theory and Applications》 1992年第2期1-10,共10页
For Hermite-Birkhoff interpolation of scattered multidumensional data by radial basis function (?),existence and characterization theorems and a variational principle are proved. Examples include (?)(r)=r^b,Duchon'... For Hermite-Birkhoff interpolation of scattered multidumensional data by radial basis function (?),existence and characterization theorems and a variational principle are proved. Examples include (?)(r)=r^b,Duchon's thin-plate splines,Hardy's multiquadrics,and inverse multiquadrics. 展开更多
关键词 HERMITE BIRKHOFF INTERPOLATION OF scatterED data BY RADIAL BASIS FUNCTIONS
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Surface Reconstruction of 3D Scattered Data with Radial Basis Functions 被引量:1
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作者 Du XIN-WEI YANG XIAO-YING LIANG XUE-ZHANG 《Communications in Mathematical Research》 CSCD 2010年第2期183-192,共10页
We use Radial Basis Functions (RBFs) to reconstruct smooth surfaces from 3D scattered data. An object's surface is defined implicitly as the zero set of an RBF fitted to the given surface data. We propose improveme... We use Radial Basis Functions (RBFs) to reconstruct smooth surfaces from 3D scattered data. An object's surface is defined implicitly as the zero set of an RBF fitted to the given surface data. We propose improvements on the methods of surface reconstruction with radial basis functions. A sparse approximation set of scattered data is constructed by reducing the number of interpolating points on the surface. We present an adaptive method for finding the off-surface normal points. The order of the equation decreases greatly as the number of the off-surface constraints reduces gradually. Experimental results are provided to illustrate that the proposed method is robust and may draw beautiful graphics. 展开更多
关键词 radial basis function scattered data implicit surface surface reconstruction
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Large Scattered Data Fitting Based on Radial Basis Functions 被引量:2
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作者 FENG Ren-zhong XU Liang 《Computer Aided Drafting,Design and Manufacturing》 2007年第1期66-72,共7页
Solving large radial basis function (RBF) interpolation problem with non-customized methods is computationally expensive and the matrices that occur are typically badly conditioned. In order to avoid these difficult... Solving large radial basis function (RBF) interpolation problem with non-customized methods is computationally expensive and the matrices that occur are typically badly conditioned. In order to avoid these difficulties, we present a fitting based on radial basis functions satisfying side conditions by least squares, although compared with interpolation the method loses some accuracy, it reduces the computational cost largely. Since the fitting accuracy and the non-singularity of coefficient matrix in normal equation are relevant to the uniformity of chosen centers of the fitted RBE we present a choice method of uniform centers. Numerical results confirm the fitting efficiency. 展开更多
关键词 scattered data radial basis functions interpolation least squares fitting uniform centers
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Mesh Generation from Dense 3D Scattered Data Using Neural Network 被引量:8
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作者 ZHANGWei JIANGXian-feng +1 位作者 CHENLi-neng MAYa-liang 《Computer Aided Drafting,Design and Manufacturing》 2004年第1期30-35,共6页
关键词 reverse engineering mesh generation neural network scattered points data extraction
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Geometric Scaling Analysis of Deep Inelastic Scattering Data Including Heavy Quarks
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作者 吴庆东 曾吉 +3 位作者 胡元元 李权波 周代翠 向文昌 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第1期31-35,共5页
An analytic massive total cross section of photon proton scattering is derived, which has geometric scaling. A geometric scaling is used to perform a global analysis of the deep inelastic scattering data on inclusive ... An analytic massive total cross section of photon proton scattering is derived, which has geometric scaling. A geometric scaling is used to perform a global analysis of the deep inelastic scattering data on inclusive structure function F2 measured in lepton-hadron scattering experiments at small values of Bjorken x. It is shown that the descriptions of the inclusive structure function F2 and longitudinal structure function FL are improved with the massive analytic structure function, which may imply the gluon saturation effect dominating the parton evolution process at HERA. The inclusion of the heavy quarks prevent the divergence of the lepton-hadron cross section, which plays a significant role in the description of the photoproduction region. 展开更多
关键词 of on in Geometric Scaling Analysis of Deep Inelastic scattering data Including Heavy Quarks that IS data been HAVE THAN from
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Analysis of the Diffractive Deep Inelastic Scattering Data with Running Coupling and Gluon Number Fluctuations
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作者 向文昌 胡志海 +2 位作者 刘万松 彭俊金 蔡绍洪 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第8期33-37,共5页
We study the effects of running coupling and gluon number fluctuations in the latest diffractive deep inelastic scattering data. It is found that the description of the data is improved once the running coupling and g... We study the effects of running coupling and gluon number fluctuations in the latest diffractive deep inelastic scattering data. It is found that the description of the data is improved once the running coupling and gluon number fluctuations are included with x2/d.o.f. = 0.867, x2/d.o.f. = 0.923 and x2/d.o.f. = 0.878 for three different groups of experimental data. The values of diffusive coefficient subtracted from the fit are smaller than the ones obtained by considering only the gluon number fluctuations in our previous studies. The smaller values of the diffusive coefficient are in agreement with the theoretical predictions, where the gluon number fluctuations are suppressed by the running coupling which leads to smaller values of the diffusive coefficient. 展开更多
关键词 of QCD Analysis of the Diffractive Deep Inelastic scattering data with Running Coupling and Gluon Number Fluctuations in is that with
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Trivariate Polynomial Natural Spline for 3D Scattered Data Hermit Interpolation
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作者 Xu YING-XIANG GUAN LU-TAI XU WEI-ZHI 《Communications in Mathematical Research》 CSCD 2012年第2期159-172,共14页
Consider a kind of Hermit interpolation for scattered data of 3D by trivariate polynomial natural spline, such that the objective energy functional (with natural boundary conditions) is minimal. By the spline functi... Consider a kind of Hermit interpolation for scattered data of 3D by trivariate polynomial natural spline, such that the objective energy functional (with natural boundary conditions) is minimal. By the spline function methods in Hilbert space and variational theory of splines, the characters of the interpolation solution and how to construct it are studied. One can easily find that the interpolation solution is a trivariate polynomial natural spline. Its expression is simple and the coefficients can be decided by a linear system. Some numerical examples are presented to demonstrate our methods. 展开更多
关键词 scattered data Hermit interpolation natural spline
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Scattered Data Interpolation Using Cubic Trigonometric Bézier
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作者 Ishak Hashim Nur Nabilah Che Draman +2 位作者 Samsul Ariffin Abdul Karim Wee Ping Yeo Dumitru Baleanu 《Computers, Materials & Continua》 SCIE EI 2021年第10期221-236,共16页
This paper discusses scattered data interpolation using cubic trigonometric Bézier triangular patches with C1 continuity everywhere.We derive the C1 condition on each adjacent triangle.On each triangular patch,we... This paper discusses scattered data interpolation using cubic trigonometric Bézier triangular patches with C1 continuity everywhere.We derive the C1 condition on each adjacent triangle.On each triangular patch,we employ convex combination method between three local schemes.The final interpolant with the rational corrected scheme is suitable for regular and irregular scattered data sets.We tested the proposed scheme with 36,65,and 100 data points for some well-known test functions.The scheme is also applied to interpolate the data for the electric potential.We compared the performance between our proposed method and existing scattered data interpolation schemes such as Powell–Sabin(PS)and Clough–Tocher(CT)by measuring the maximum error,root mean square error(RMSE)and coefficient of determination(R^(2)).From the results obtained,our proposed method is competent with cubic Bézier,cubic Ball,PS and CT triangles splitting schemes to interpolate scattered data surface.This is very significant since PS and CT requires that each triangle be splitting into several micro triangles. 展开更多
关键词 Cubic trigonometric Bézier triangular patches C1sufficient condition scattered data interpolation
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A new package:MySAS for small angle scattering data analysis 被引量:3
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作者 Huang Chaoqiang Xia Qingzhong +2 位作者 Yan Guanyun Sun Guang'ai Chen Bo 《Nuclear Science and Techniques》 SCIE CAS CSCD 2010年第6期325-329,共5页
In this paper,A MySAS package,which is verified on Windows XP,can easily convert two-dimensional data in small angle neutron and X-ray scattering analysis,operate individually and execute one particular operation as n... In this paper,A MySAS package,which is verified on Windows XP,can easily convert two-dimensional data in small angle neutron and X-ray scattering analysis,operate individually and execute one particular operation as numerical data reduction or analysis,and graphical visualization.This MySAS package can implement the input and output routines via scanning certain properties,thus recalling completely sets of repetition input and selecting the input files.On starting from the two-dimensional files,the MySAS package can correct the anisotropic or isotropic data for physical interpretation and select the relevant pixels.Over 50 model functions are fitted by the POWELL code using x^2 as the figure of merit function. 展开更多
关键词 数据分析 小角散射 WINDOWS 二维数据 重复输入 输入文件 X射线散射 数据还原
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C^1 C^2INTERPOLATION OF SCATTERED DATA POINTS 
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作者 WANG JIAYE AND ZHANG CAIMING(Department of Computer Science,Shandong University Jinan 250100) 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1994年第1期1-9,共9页
C~1C~2INTERPOLATIONOFSCATTEREDDATAPOINTS¥WANGJIAYEANDZHANGCAIMING(DepartmentofComputerScience,ShandongUnivers... C~1C~2INTERPOLATIONOFSCATTEREDDATAPOINTS¥WANGJIAYEANDZHANGCAIMING(DepartmentofComputerScience,ShandongUniversityJinan250100)Ab... 展开更多
关键词 散乱数据点 C^1 C^2 插值 多项式 计算方法 三角形 重心坐标
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Geometric Feature Extraction and Model Reconstruction Based on Scattered Data
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作者 胡鑫 习俊通 金烨 《Journal of Donghua University(English Edition)》 EI CAS 2004年第4期86-89,共4页
A method of 3D model reconstruction based on scattered point data in reverse engineering is presented here. The topological relationship of scattered points was established firstly, then the data set was triangulated ... A method of 3D model reconstruction based on scattered point data in reverse engineering is presented here. The topological relationship of scattered points was established firstly, then the data set was triangulated to reconstruct the mesh surface model. The curvatures of cloud data were calculated based on the mesh surface, and the point data were segmented by edge-based method; Every patch of data was fitted by quadric surface of freeform surface, and the type of quadric surface was decided by parameters automatically, at last the whole CAD model was created. An example of mouse model was employed to confirm the effect of the algorithm. 展开更多
关键词 数学建模 离散数据 反转工程学 特征抽出 计算机辅助设计 曲率
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Hermite interpolation of scattered data based on the assistant surface
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作者 王全为 李学艺 +1 位作者 李彬 王小椿 《Journal of Coal Science & Engineering(China)》 2006年第2期108-111,共4页
An assistant surface was constructed on the base of boundary that being auto-matically extracted from the scattered data.The parameters of every data point corre-sponding to the assistant surface and their applied fie... An assistant surface was constructed on the base of boundary that being auto-matically extracted from the scattered data.The parameters of every data point corre-sponding to the assistant surface and their applied fields were calculated respectively.Inevery applied region,a surface patch was constructed by a special Hermite interpolation.The final surface can be obtained by a piecewise bicubic Hermite interpolation in the ag-gregate of applied regions of metrical data.This method avoids the triangulation problem.Numerical results indicate that it is efficient and accurate. 展开更多
关键词 离散数据 几何表面 边界曲线 曲面构造 埃尔米特插值
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Data Processing and Acquisition System for the HT-7 Multipulse Thomson Scattering Diagnostic
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作者 陈卓天 赵君煜 +2 位作者 方自深 李亚东 杨利 《Plasma Science and Technology》 SCIE EI CAS CSCD 2003年第4期1867-1872,共6页
This article describes the data processing and acquisition system for the HT-7 mul-tipulse Thomson scattering diagnostic. An eight-pulse laser is used in the Thomson scattering system to obtain electron temperature pr... This article describes the data processing and acquisition system for the HT-7 mul-tipulse Thomson scattering diagnostic. An eight-pulse laser is used in the Thomson scattering system to obtain electron temperature profiles at eight different times throughout an entire plasma discharge. The major components of the diagnostic system consist of a multipulse Nd-glass laser, a photodetector's subsystem, a calibration set and a CAMAC data processing and acquisition system. The data processing software along with LeCroy 2250L will perform the data acquisition. In order to simplify the operation and extend the capability of its compatibility with other math softwares, the processing software has been improved by the authors. The new software based on the VC++ easily utilizes some math softwares to calculate the electron temperature. The new software is simpler and more operational than the old one. 展开更多
关键词 laser Thomson scattering diagnostic electron temperature data acquisition
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Minimum Data Sampling Method in the Inverse Scattering Problem
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作者 Yu Wenhua(Res. Inst. of EM Field and Microwave Tech.), Southwest Jiaotong University, Chengdu 610031 ,ChinaPeng Zhongqiu(Beijng Remote Sensing and Information Institute),Beijing 100011,ChinaRen Lang(Res.inst. of EM Field and Microwave Tech.), Southwest J 《Journal of Modern Transportation》 1994年第2期114-118,共5页
Fourier transform is a basis of the analysis. This paper presents a kind ofmethod of minimum sampling data determined profile of the inverted object ininverse scattering.
关键词 inverse scattering nonuniqueness sampling data
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空中目标动态电磁散射数据仿真系统设计与实现
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作者 商城 徐志明 +4 位作者 张杨 张楷煜 吴其华 朱义奇 艾小锋 《现代防御技术》 北大核心 2024年第2期163-171,共9页
电磁散射数据是目标识别研究的基础,但由于试验测量成本高、可重复性差等问题,空中目标电磁散射实测数据十分有限。基于去遮挡的N点模型和电磁计算数据插值研究了空中目标动态电磁散射数据仿真方法,设计了空中目标动态电磁数据仿真系统... 电磁散射数据是目标识别研究的基础,但由于试验测量成本高、可重复性差等问题,空中目标电磁散射实测数据十分有限。基于去遮挡的N点模型和电磁计算数据插值研究了空中目标动态电磁散射数据仿真方法,设计了空中目标动态电磁数据仿真系统,该系统将电磁散射仿真与实际飞行场景相结合,支持场景自定义和空中目标三维模型库扩展。分析了飞机和巡航导弹2类目标仿真数据及成像结果,结果验证了仿真方法正确性和系统有效性,可为研究实际场景下的空中目标识别提供支撑。 展开更多
关键词 空中目标 电磁散射数据 宽带雷达 仿真系统 自动目标识别 散射中心模型
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用于不平衡类癌症数据的非标记检测和识别的SERS分析新策略
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作者 曹大卫 徐慧英 +3 位作者 林合川 刘子洋 朱信忠 钱亚云 《浙江师范大学学报(自然科学版)》 CAS 2024年第3期257-265,共9页
SERS技术与机器学习结合的策略在检测和识别不平衡类癌症中发挥着极其重要的作用.为了解决类不平衡问题给分类精度造成的影响,设计了一种SERS技术结合APS-SMOTE-PCA-KNN(synthetic minority oversampling method with adaptive priority... SERS技术与机器学习结合的策略在检测和识别不平衡类癌症中发挥着极其重要的作用.为了解决类不平衡问题给分类精度造成的影响,设计了一种SERS技术结合APS-SMOTE-PCA-KNN(synthetic minority oversampling method with adaptive priority selection(APS-SMOTE)-principal component analysis(PCA)-k-nearest neighbors(KNN))的癌症诊断新策略,实现快速、灵敏、非标记地检测和识别癌症.结果显示:新策略能够测得健康人和癌症患者血清的特征光谱,很好地解决了类不平衡问题给分类精度造成的影响,准确率可以达到85.0%.SERS技术结合APS-SMOTE-PCA-KNN对于未来癌症诊断具有积极的借鉴意义. 展开更多
关键词 表面增强拉曼散射 癌症 不平衡类数据 特征峰 合成少数类过采样方法
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面向通感一体系统的耐弯三芯光纤
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作者 张泽霖 秦钰 +5 位作者 周慧 许维维 蒋新力 马麟 沈一春 肖力敏 《光通信技术》 北大核心 2024年第1期80-84,共5页
为了同时兼顾狭小空间下的光纤数据通信与环境感知,设计并制备了一种面向通感一体系统的耐弯三芯光纤。该光纤采用三角形纤芯排布和深掺氟折射率沟道结构,标准外径为125μm,优化了O波段(1260~1360 nm)的传输特性,具有与G.657.A1光纤相... 为了同时兼顾狭小空间下的光纤数据通信与环境感知,设计并制备了一种面向通感一体系统的耐弯三芯光纤。该光纤采用三角形纤芯排布和深掺氟折射率沟道结构,标准外径为125μm,优化了O波段(1260~1360 nm)的传输特性,具有与G.657.A1光纤相似的布里渊增益谱(BGS)分布。测试结果表明:在1310 nm波长处,芯层的平均损耗为0.58 dB/km,平均芯间串扰低于-50 dB/km;当最小弯曲半径R=10 mm且缠绕50圈时,光纤的弯曲损耗低于0.1 dB。 展开更多
关键词 三芯光纤 弯曲损耗 受激布里渊散射 快速测量 数据通信
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多采样率地震勘探技术(MrSET)探讨
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作者 倪宇东 姜福豪 +4 位作者 邹雪峰 蓝益军 柳兴刚 门哲 许银坡 《地球物理学报》 SCIE EI CAS CSCD 北大核心 2024年第3期1169-1180,共12页
时间采样以及空间采样问题是地震勘探基本问题,空间采样方式包括规则采样、非均匀(非规则)采样、随机采样等.从地震波场的带限性、空间域非均匀性、地下构造多样性出发,提出多采样率地震勘探技术(MrSET),尝试组合不同空间采样方式.多采... 时间采样以及空间采样问题是地震勘探基本问题,空间采样方式包括规则采样、非均匀(非规则)采样、随机采样等.从地震波场的带限性、空间域非均匀性、地下构造多样性出发,提出多采样率地震勘探技术(MrSET),尝试组合不同空间采样方式.多采样率地震勘探观测系统设计一般应满足5项准则,探讨了多采样率数据处理基本方法,并以合成数据和实际数据的处理效果为基础,总结了多采样率地震勘探技术的7个方面优势.在相同道密度前提下,与规则采样相比,多采样率地震勘探技术更能满足复杂地震波场、弱能量绕射波与散射波充分采样的需要,是一项能提高反射地震数据成像精度的地震勘探技术,经过进一步研究将有巨大潜力成为(陆上、海洋)节点地震勘探时代常规技术. 展开更多
关键词 规则采样 随机采样 非均匀(非规则)采样 多采样率采样 逆散射成像 数据重构
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基于分子干涉函数的光子-原子相干散射截面计算方法研究
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作者 徐宁 祖铁军 +1 位作者 曹良志 吴宏春 《原子能科学技术》 EI CAS CSCD 北大核心 2024年第3期573-580,共8页
X射线衍射在物质结构分析和材料无损检测领域有着广泛的应用,其基本物理原理为光子与物质发生的相干散射。传统的相干散射截面计算方法基于独立原子形状因子近似方法,忽略了光子动量转移较小时与原子发生相互作用时的分子干涉效应,影响... X射线衍射在物质结构分析和材料无损检测领域有着广泛的应用,其基本物理原理为光子与物质发生的相干散射。传统的相干散射截面计算方法基于独立原子形状因子近似方法,忽略了光子动量转移较小时与原子发生相互作用时的分子干涉效应,影响相干散射截面的计算精度。因此,为了获得光子动量转移较小时精确的相干散射截面,本文在核数据处理程序NECP-Atlas中对基于分子干涉函数的光子-原子相干散射截面计算方法进行研究,利用分子动力学模拟方法计算分子干涉函数,对蒙特卡罗程序使用的ACE格式数据库中的原子形状因子进行修正,并给出了模拟得到的水分子和乙醇分子的分子干涉函数,对基于独立原子形状因子近似方法和考虑分子干涉效应计算得到的水和乙醇的散射成像结果进行了对比分析。数值结果显示:基于分子动力学模拟得到的分子干涉函数计算得到的水的散射成像结果与文献结果吻合较好;同时,当光子动量转移较小时,分子干涉效应对相干散射的次级光子角度分布有着显著影响。本文建立的光子-原子相干散射截面计算方法可显著提高光子动量转移较小时的相干散射次级光子角度分布计算精度,可为X射线衍射模拟提供数据基础。 展开更多
关键词 核数据处理 光子 相干散射 原子形状因子 分子干涉效应 NECP-Atlas
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GSVM:一种支持Gather/Scatter的向量存储器
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作者 陈海燕 刘胜 吴健虢 《国防科技大学学报》 EI CAS CSCD 北大核心 2020年第3期1-8,共8页
宽单指令多数据流(Single Instruction Multiple Data,SIMD)架构数字信号处理器一般都能高效支持地址连续或等距跨步等规则应用的向量访存,但对于科学与工程计算中广泛存在的不规则应用的数据访存则带宽利用率往往较低,从而大幅降低了... 宽单指令多数据流(Single Instruction Multiple Data,SIMD)架构数字信号处理器一般都能高效支持地址连续或等距跨步等规则应用的向量访存,但对于科学与工程计算中广泛存在的不规则应用的数据访存则带宽利用率往往较低,从而大幅降低了其整体运算能效。为了提高不规则应用的向量访存性能,基于某SIMD数字信号处理器的体系结构,设计了一种支持Gather/Scatter访存的向量存储器GSVM。通过设计与SIMD宽度相匹配的向量地址计算单元和合适深度的冲突缓冲器阵列,实现了Gather/Scatter指令向量地址计算、仲裁与缓存的全流水访存操作。实验结果表明,相比以前不支持Gather/Scatter访存的存储器,GSVM在增加22%的硬件代价基础上,基于稀疏矩阵向量乘的测试程序集获得了2~8的性能加速比。 展开更多
关键词 单指令多数据流 Gather/scatter 向量随机访存 访存冲突
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