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不完全正交的变参数H-IGMRES(m)算法 被引量:1
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作者 于春肖 杨艳芳 井丁卉 《郑州大学学报(理学版)》 CAS 北大核心 2020年第1期93-98,共6页
为了提高大型线性方程组的求解速率,在变参数H-GMRES(m)算法的基础上,利用不完全正交的Householder变换,提出了截断型的H-IGMRES(m)算法。对算法的收敛性进行了分析,用数值算例验证了算法的可行性,同时对算法的计算精度和效率进行了比... 为了提高大型线性方程组的求解速率,在变参数H-GMRES(m)算法的基础上,利用不完全正交的Householder变换,提出了截断型的H-IGMRES(m)算法。对算法的收敛性进行了分析,用数值算例验证了算法的可行性,同时对算法的计算精度和效率进行了比较。理论分析和研究结果表明,所提出的截断型算法在保证计算精度的前提下,大大减少了迭代次数,显著提高了计算效率。 展开更多
关键词 H-GmRES(m)算法 不完全正交 截断型 h-igmres(m)算法
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m-WG逆的性质和计算
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作者 韦华全 吴辉 +1 位作者 刘晓冀 靳宏伟 《数学物理学报(A辑)》 CSCD 北大核心 2024年第3期547-562,共16页
该文研究了闵可夫斯基空间中矩阵的m-WG逆的性质和计算.首先,利用值域和零空间给出了m-WG逆的刻画.其次,给出了m-WG逆与非奇异加边矩阵之间的关系,并讨论了m-WG逆的扰动界.最后,利用逐次矩阵平方算法给出了m-WG逆的计算.
关键词 m-WG逆 加边矩阵 扰动界 逐次矩阵平方算法
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阻尼改进抗差L-M匹配下全景图像拼接平滑优化
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作者 薛鸿民 《电子设计工程》 2024年第15期176-179,184,共5页
为了解决大面积视觉全景图像受拼接缝影响,拼接平滑面积较小的问题,提出阻尼改进抗差L-M匹配下全景图像拼接平滑优化方法。阻尼因子改进抗差L-M算法,计算抗差L-M迭代向量;利用改进抗差L-M算法,融合球面投影理论,对特征匹配误差目标函数... 为了解决大面积视觉全景图像受拼接缝影响,拼接平滑面积较小的问题,提出阻尼改进抗差L-M匹配下全景图像拼接平滑优化方法。阻尼因子改进抗差L-M算法,计算抗差L-M迭代向量;利用改进抗差L-M算法,融合球面投影理论,对特征匹配误差目标函数进行优化。融合拉普拉斯算法和高斯滤波金字塔对图像进行分解重构,确定图像拼接缝重叠区域后完成全景图像拼接平滑优化。实验结果表明,所提方法的拼接缝平滑面积能够达到95.8%,解决了拼接平滑面积较小的问题。 展开更多
关键词 抗差L-m算法 全景图像 图像拼接缝 拼接缝消除
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基于L-M算法的铝合金铸造过程界面换热系数的反问题模型
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作者 王一帆 温治 +1 位作者 豆瑞锋 于博 《热加工工艺》 北大核心 2024年第9期122-129,共8页
铝合金铸造过程铸件-铸模之间的界面换热系数的变化非常复杂,且预测非常困难。本文基于L-M(Levenberg-Marquardt)算法建立了铝合金铸造过程传热反问题模型,通过反问题分析获得铝合金铸造过程中铸件-铸模界面换热系数。通过将铸件-铸模... 铝合金铸造过程铸件-铸模之间的界面换热系数的变化非常复杂,且预测非常困难。本文基于L-M(Levenberg-Marquardt)算法建立了铝合金铸造过程传热反问题模型,通过反问题分析获得铝合金铸造过程中铸件-铸模界面换热系数。通过将铸件-铸模界面换热系数反演值与标准值进行比较,验证传热反问题模型的准确性。在此基础上,分析了铸模上测点位置(与铸件-铸模界面距离、相邻测点间距)和温度测量误差对铸件-铸模界面换热系数反演值的影响规律,并给出了最优的测点布置方案和温度测量误差要求。通过铝合金铸造实验,用该反问题模型能求解出铝合金凝固过程中的铸件-铸模界面换热系数。 展开更多
关键词 铸造 反传热模型 LEVENBERG-mARQUARDT算法 界面换热系数 凝固
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Bayesian Classifier Based on Robust Kernel Density Estimation and Harris Hawks Optimisation
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作者 Bi Iritie A-D Boli Chenghao Wei 《International Journal of Internet and Distributed Systems》 2024年第1期1-23,共23页
In real-world applications, datasets frequently contain outliers, which can hinder the generalization ability of machine learning models. Bayesian classifiers, a popular supervised learning method, rely on accurate pr... In real-world applications, datasets frequently contain outliers, which can hinder the generalization ability of machine learning models. Bayesian classifiers, a popular supervised learning method, rely on accurate probability density estimation for classifying continuous datasets. However, achieving precise density estimation with datasets containing outliers poses a significant challenge. This paper introduces a Bayesian classifier that utilizes optimized robust kernel density estimation to address this issue. Our proposed method enhances the accuracy of probability density distribution estimation by mitigating the impact of outliers on the training sample’s estimated distribution. Unlike the conventional kernel density estimator, our robust estimator can be seen as a weighted kernel mapping summary for each sample. This kernel mapping performs the inner product in the Hilbert space, allowing the kernel density estimation to be considered the average of the samples’ mapping in the Hilbert space using a reproducing kernel. M-estimation techniques are used to obtain accurate mean values and solve the weights. Meanwhile, complete cross-validation is used as the objective function to search for the optimal bandwidth, which impacts the estimator. The Harris Hawks Optimisation optimizes the objective function to improve the estimation accuracy. The experimental results show that it outperforms other optimization algorithms regarding convergence speed and objective function value during the bandwidth search. The optimal robust kernel density estimator achieves better fitness performance than the traditional kernel density estimator when the training data contains outliers. The Naïve Bayesian with optimal robust kernel density estimation improves the generalization in the classification with outliers. 展开更多
关键词 CLASSIFICATION Robust Kernel Density Estimation m-ESTImATION Harris Hawks Optimisation algorithm Complete Cross-Validation
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A Reduced Search Soft-Output Detection Algorithm and Its Application to Turbo-Equalization
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作者 樊祥宁 窦怀宇 毕光国 《Journal of Southeast University(English Edition)》 EI CAS 2001年第1期8-12,共5页
To decrease the complexity of MAP algorithm, reduced state or reduced search techniques can be applied. In this paper we propose a reduced search soft output detection algorithm fully based on the principle of M a... To decrease the complexity of MAP algorithm, reduced state or reduced search techniques can be applied. In this paper we propose a reduced search soft output detection algorithm fully based on the principle of M algorithm for turbo equalization, which is a suboptimum version of the Lee algorithm. This algorithm is called soft output M algorithm (denoted as SO M algorithm), which applies the M strategy to both the forward recursion and the extended forward recursion of the Lee algorithm. Computer simulation results show that, by properly selecting and adjusting the breadth parameter and depth parameter during the iteration of turbo equalization, this algorithm can obtain good performance and complexity trade off. 展开更多
关键词 mAP algorithm Lee algorithm soft output m algorithm turbo equalization
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Application of the L-M optimized algorithm to predicting blast vibration parameters 被引量:6
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作者 张艺峰 姚道平 +2 位作者 谢志招 杨江峰 叶友权 《地震学报》 CSCD 北大核心 2008年第5期540-544,554,共5页
当前,以振动峰值作为单一爆破振动安全指标的回归经验公式,在国内外爆破工程界得到广泛应用.但由于爆破机理和爆破介质环境复杂,影响因素诸多,很难用一个经验公式把这些因素都考虑进去;再加上回归分析方法固有的局限性(要求数据... 当前,以振动峰值作为单一爆破振动安全指标的回归经验公式,在国内外爆破工程界得到广泛应用.但由于爆破机理和爆破介质环境复杂,影响因素诸多,很难用一个经验公式把这些因素都考虑进去;再加上回归分析方法固有的局限性(要求数据有较好的分布规律和大样本量),经验公式方法进行振动预测的效果不甚理想(李保珍,1997;陈寿如,2001;张继春,2001). 展开更多
关键词 爆破振动 神经网络 L-m算法 预测
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Nonlinear optimal model and solving algorithms for platform planning problem in battlefield 被引量:2
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作者 WANG Xun YAO Peiyang +1 位作者 ZHANG Jieyong WAN Lujun 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第5期983-994,共12页
Platform planning is one of the important problems in the command and control(C2) field. Hereto, we analyze the platform planning problem and present nonlinear optimal model aiming at maximizing the task completion qu... Platform planning is one of the important problems in the command and control(C2) field. Hereto, we analyze the platform planning problem and present nonlinear optimal model aiming at maximizing the task completion qualities. Firstly, we take into account the relation among tasks and build the single task nonlinear optimal model with a set of platform constraints. The Lagrange relaxation method and the pruning strategy are used to solve the model. Secondly, this paper presents optimization-based planning algorithms for efficiently allocating platforms to multiple tasks. To achieve the balance of the resource assignments among tasks, the m-best assignment algorithm and the pair-wise exchange(PWE)method are used to maximize multiple tasks completion qualities.Finally, a series of experiments are designed to verify the superiority and effectiveness of the proposed model and algorithms. 展开更多
关键词 platform planning nonlinear optimal model Lagrange relaxation method m-best algorithm pair-wise exchange(PWE)
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Greedy Algorithm in m-Term Approximation for Periodic Besov Class with Mixed Smoothness
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作者 宋占杰 叶培新 《Transactions of Tianjin University》 EI CAS 2009年第1期75-78,共4页
Nonlinear m-term approximation plays an important role in machine learning, signal processing and statistical estimating. In this paper by means of a nondecreasing dominated function, a greedy adaptive compression num... Nonlinear m-term approximation plays an important role in machine learning, signal processing and statistical estimating. In this paper by means of a nondecreasing dominated function, a greedy adaptive compression numerical algorithm in the best m -term approximation with regard to tensor product wavelet-type basis is pro-posed. The algorithm provides the asymptotically optimal approximation for the class of periodic functions with mixed Besov smoothness in the L q norm. Moreover, it depends only on the expansion of function f by tensor pro-duct wavelet-type basis, but neither on q nor on any special features of f. 展开更多
关键词 greedy algorithm m -term approximation Besov space mixed smoothness
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PARTIAL ELIMINTATION ALGORITHM FOR A LINEAR RECURRENCE SYSTEM R(n, m) OF ORDER m
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作者 郑慧娆 黄传河 樊戊 《Acta Mathematica Scientia》 SCIE CSCD 1993年第3期241-250,共10页
This paper presents an algorithm for computing a linear recurrence system R(n, m) of order m for n equations on MIMD parallel system. This algorithm is not only easy to be programmed on a parallel computer system, but... This paper presents an algorithm for computing a linear recurrence system R(n, m) of order m for n equations on MIMD parallel system. This algorithm is not only easy to be programmed on a parallel computer system, but also reduces the data-waiting time due to compute-ahead strategy. The paper analyses how to achieve maximal load balancing when the algorithm is implemented on MIMD parallel system. By the end of the paper, an analysis on the speedup and parallel efficiency are given. The results indicate that the new parallel elimination algorithm has great improvement compared with the old ones. 展开更多
关键词 mImD OF ORDER m PARTIAL ELImINTATION algorithm FOR A LINEAR RECURRENCE SYSTEm R
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On Over-Relaxed Proximal Point Algorithms for Generalized Nonlinear Operator Equation with (A,η,m)-Monotonicity Framework
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作者 Fang Li 《International Journal of Modern Nonlinear Theory and Application》 2012年第3期67-72,共6页
In this paper, a new class of over-relaxed proximal point algorithms for solving nonlinear operator equations with (A,η,m)-monotonicity framework in Hilbert spaces is introduced and studied. Further, by using the gen... In this paper, a new class of over-relaxed proximal point algorithms for solving nonlinear operator equations with (A,η,m)-monotonicity framework in Hilbert spaces is introduced and studied. Further, by using the generalized resolvent operator technique associated with the (A,η,m)-monotone operators, the approximation solvability of the operator equation problems and the convergence of iterative sequences generated by the algorithm are discussed. Our results improve and generalize the corresponding results in the literature. 展开更多
关键词 New Over-Relaxed Proximal Point algorithm Nonlinear OPERATOR Equation with (A η m)-monotonicity FRAmEWORK Generalized RESOLVENT OPERATOR Technique Solvability and Convergence
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Research on Algorithm M8 Applying to TIP Prediction of China's Strong Earthquake Cases in the Past Decades
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作者 Huang Deyu and Chen YongCenter for Analysis and Prediction,SSB,Beijing 100036,China State Seismological Bureau,Beijing 100036,China 《Earthquake Research in China》 1994年第4期4-10,共7页
This paper offers a positive research result of TIP before 16 strong earthquakes in North and Southwest China and their nearby areas since 1979 by using improved algorithm M8.The result showed that 14 of them were det... This paper offers a positive research result of TIP before 16 strong earthquakes in North and Southwest China and their nearby areas since 1979 by using improved algorithm M8.The result showed that 14 of them were determined to occur within the times of increased probability.TIP precaution occupies about 37% of the total space-time domain.That means we have made quite good results of intermediate-term prediction of strong earthquakes.So the method could be used as one of the useful means of the intermediate-term prediction of strong earthquakes. 展开更多
关键词 m8 algorithm Intermediate-term earthquake PREDICTION
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LEVERRIER'S ALGORITHM FOR m-D SYSTEM
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作者 王国荣 郑兵 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2004年第1期10-23,共14页
A Leverrier-like algorithm is presented which allows the computation of the transfer function of a linear regular system from its m-D state-space description,without inverting a multivariable polynomial matrix. This a... A Leverrier-like algorithm is presented which allows the computation of the transfer function of a linear regular system from its m-D state-space description,without inverting a multivariable polynomial matrix. This algorithm is an extension of the classic Leverrier's algorithm for 1-D system and it reduces the computational cost.ra-D Cayley-Hamilton theorem is also shown by the algorithm. 展开更多
关键词 LEVERRIER算法 多维系统 凯莱-哈密顿理论 状态空间矩阵 多元多项式矩阵 控制论
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A DIRECT ALGORITHM FOR DISTINGUISHING NONSINGULAR M-MATRIX AND H-MATRIX
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作者 李耀堂 朱艳 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2005年第1期79-86,共8页
A direct algorithm is proposed by which one can distinguish whether a matrix is an M-matrix (or H-matrix) or not quickly and effectively. Numerical examples show that it is effective and convincible to distinguish M-m... A direct algorithm is proposed by which one can distinguish whether a matrix is an M-matrix (or H-matrix) or not quickly and effectively. Numerical examples show that it is effective and convincible to distinguish M-matrix (or H-matrix) by using the algorithm. 展开更多
关键词 计算方法 非奇m-矩阵 H-矩阵 线性代数
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An Algorithm for Cavity Reconstruction in Electrical Impedance Tomography
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作者 FENG TIAN-HONG MA FU-MING 《Communications in Mathematical Research》 CSCD 2011年第3期279-288,共10页
We consider the inverse problem of finding cavities within some object from electrostatic measurements on the boundary. By a cavity we understand any object with a different electrical conductivity from the background... We consider the inverse problem of finding cavities within some object from electrostatic measurements on the boundary. By a cavity we understand any object with a different electrical conductivity from the background material of the body. We give an algorithm for solving this inverse problem based on the output nonlinear least-square formulation and the regularized Newton-type iteration. In particular, we present a number of numerical results to highlight the potential and the limitations of this method. 展开更多
关键词 electrical impedance tomography CONDUCTIVITY Levenberg-marquardt (L-m algorithm
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基于L-M算法的移动载荷识别数值分析与研究 被引量:1
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作者 唐高阳 《科技资讯》 2023年第7期196-200,共5页
近几年,国内运输行业呈现出了极为迅猛的发展趋势,作为连接各地区的主体,桥梁在促进经济发展等方面起到重大作用,如何在保证桥梁性能的前提下,对其寿命进行延长已成为社会各界热议的话题。文章以移动载荷识别为切入点,首先对识别所用L-... 近几年,国内运输行业呈现出了极为迅猛的发展趋势,作为连接各地区的主体,桥梁在促进经济发展等方面起到重大作用,如何在保证桥梁性能的前提下,对其寿命进行延长已成为社会各界热议的话题。文章以移动载荷识别为切入点,首先对识别所用L-M算法进行了介绍,其次以斜拉桥、简支梁为例,围绕载荷识别、结构分析相关内容展开了讨论,最后以研究所得出结论为依据,针对不确定参数建立了相应的分析模型,创造性地引入了模糊隶属度等指标,希望能够为日后计算响应区间等工作的开展提供帮助。 展开更多
关键词 L-m算法 载荷识别 响应分析 桥梁结构
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A SIMPLIFIED QRD-M SIGNAL DETECTION ALGORITHM FOR MIMO-OFDM SYSTEMS
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作者 Jian Haifang Yao Xiaocheng Shi Yin 《Journal of Electronics(China)》 2010年第1期88-93,共6页
QR Decompositon with an M-algorithm(QRD-M) has good performance with low complexity,which is considered as a promising technique in Multiple-Input Multiple-Output(MIMO) detections.This paper presented a simplified QRD... QR Decompositon with an M-algorithm(QRD-M) has good performance with low complexity,which is considered as a promising technique in Multiple-Input Multiple-Output(MIMO) detections.This paper presented a simplified QRD-M algorithm for MIMO Orthogonal Frequency Division Multiplexing(MIMO-OFDM) systems.In the proposed scheme,each surviving path is expanded only to partial branches in order to carry out a limited tree search.The nodes are expanded on demand and sorted in a distributed manner,based on the novel expansion scheme which can pre-determine the children's ascending order by their local distances.Consequently,the proposed scheme can significantly decrease the complexity compared with conventional QRD-M algorithm.Hence,it is especially attractive to VLSI implementation of the high-throughput MIMO-OFDM systems.Simulation results prove that the proposed scheme can achieve a performance very close to the conventional QRD-M algorithm. 展开更多
关键词 multiple-Input multiple-Output(mImO) Orthogonal Frequency Division multiplexing(OFDm) QR Decompositon with an m-algorithm(QRD-m) Detection
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PARALLEL(M-N) SVD ALGORITHMS ON THE SIMD COMPUTERS
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作者 Wang Guorong Wei Yimin(Dept. of Mathematics, Shanghai Normal University Shanghai 200234, P. R. China Institute of Mathematics, Fudan University Shanghai 200133, P. R. China) 《Wuhan University Journal of Natural Sciences》 CAS 1996年第Z1期541-546,共6页
Let A be m by n matrix, M and N be positive definite matrices of order in and n respectively. This paper presents an efficient method for computing (M-N) singular value decomposition((M-N) SVD) of A on a cube connecte... Let A be m by n matrix, M and N be positive definite matrices of order in and n respectively. This paper presents an efficient method for computing (M-N) singular value decomposition((M-N) SVD) of A on a cube connected single instruction stream-multiple data stream(SIMD) parallel computer. This method is based on a one-sided orthogonalization algorithm due to Hestenes. On the cube connected SIMD parallel computer with o(n) processors, the (M -- N) SVD of a matrix A requires a computation time of o(m3 log m/n). 展开更多
关键词 Parallel algorithm cube connected SImD machine (m-N) SVD.
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A Sphere Detection Based Adaptive MIMO Detection Algorithm for LTE-A System
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作者 Xuanli Wu Lukuan Sun Mingxin Luo 《Communications and Network》 2013年第2期25-29,共5页
An adaptive MIMO detection algorithm for LTE-A system which is based on sphere detection is proposed in this paper. The proposed algorithm uses M-algorithm for reference to remove unreliable constellation candidates b... An adaptive MIMO detection algorithm for LTE-A system which is based on sphere detection is proposed in this paper. The proposed algorithm uses M-algorithm for reference to remove unreliable constellation candidates before search, and the number of constellation reservation is adaptively adjusted according to SNR. Simulations of LTE-A downlink show that the BER performance of the proposed detection algorithm is nearly the same as maximum likelihood (ML) detection algorithm. However, the complexity is reduced by about 30% compared with full constellation sphere detection. 展开更多
关键词 ADAPTIVE mImO DETECTION SPHERE DETECTION m-algorithm LTE-A System
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基于ArcGIS的30 m地表覆盖数据生产与质检软件研发与应用 被引量:2
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作者 陈适 田清丰 +2 位作者 马文涛 吴蓉蓉 陈佳 《测绘与空间地理信息》 2023年第3期87-90,共4页
基于30 m地表覆盖数据(GlobeLand30)处理相关理论、算法以及软件设计方法,并基于ArcGIS平台,研发了面向GlobeLand30数据准备、数据预处理、数据生产、项目管理和数据质检等流程的专业软件。该软件分为栅格编辑、辅助工具、检查工具、设... 基于30 m地表覆盖数据(GlobeLand30)处理相关理论、算法以及软件设计方法,并基于ArcGIS平台,研发了面向GlobeLand30数据准备、数据预处理、数据生产、项目管理和数据质检等流程的专业软件。该软件分为栅格编辑、辅助工具、检查工具、设置与注册4个模块,有工具40余个。介绍了软件的主要功能、面向对象的设计理念、创新性的算法设计。软件自主编写了栅格准备、编辑与检查的一系列算法。提出了数据准备模板化的数据更新方式,开创了基于ArcGIS的30 m地表覆盖数据实时编辑的生产模式。支持自动保存机制,回撤编辑不区分操作方式,约束是否编辑0值,保障数据安全。提供了分景数据和裁切影像的相关检查工具,可以定位、定性、定量、准确、完备地查找错误,优化了检查方式。根据使用单位反馈,软件各项指标均满足应用单位生产与质检需求。 展开更多
关键词 30 m地表覆盖数据 栅格编辑算法 数据更新 数据安全 数据检查
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