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An Integration of Meaning-Focused and Form-Focused Approach in EFL Reading and Writing——a Conceptual Inquiry and Experiment
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作者 王智杰 《海外英语》 2017年第22期247-248,250,共3页
Whether to adopt the meaning-oriented or form-oriented approach in EFL teaching has been in hot academic debate in the past decades. This paper investigates the literature contribution on these two methods, attempts a... Whether to adopt the meaning-oriented or form-oriented approach in EFL teaching has been in hot academic debate in the past decades. This paper investigates the literature contribution on these two methods, attempts an integration of the two,and introduces a teaching experiment of EFL reading and writing at China Agricultural University. 展开更多
关键词 integrATION meanING FORM College English Reading and Writing
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INTEGRABLE SYSTEM AND SPACELIKE SURFACES WITH PRESCRIBED MEAN CURVATURE IN MINKOWSKI 3-SPACE 被引量:1
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作者 曹锡芳 田畴 《Acta Mathematica Scientia》 SCIE CSCD 1999年第1期91-96,共6页
Authors discover that a spacelike surface in Minkowski 3-space is related to a integrable system. They obtain a representation formula for spacelike surfaces with prescribed mean curvature. This representation formula... Authors discover that a spacelike surface in Minkowski 3-space is related to a integrable system. They obtain a representation formula for spacelike surfaces with prescribed mean curvature. This representation formula is equivalent to that obtained ly Akutagawa and Nishikawa. 展开更多
关键词 integrable system spacelike surfaces mean curvature
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Wavelet Density Estimation of Censoring Data and Evaluate of Mean Integral Square Error with Convergence Ratio and Empirical Distribution of Given Estimator 被引量:1
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作者 Mahmoud Afshari 《Applied Mathematics》 2014年第13期2062-2072,共11页
Wavelet has rapid development in the current mathematics new areas. It also has a double meaning of theory and application. In signal and image compression, signal analysis, engineering technology has a wide range of ... Wavelet has rapid development in the current mathematics new areas. It also has a double meaning of theory and application. In signal and image compression, signal analysis, engineering technology has a wide range of applications. In this paper, we use wavelet method, for estimating the density function for censoring data. We evaluate the mean integrated squared error, convergence ratio of given estimator. Also, we obtain empirical distribution of given estimator and verify the conclusion by two simulation examples. 展开更多
关键词 WAVELET Estimation CENSORING mean integrAL ERROR CONVERGENCE
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Integral Mean Estimates for Polynomials Whose Zeros are within a Circle
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作者 Yash Paul Wali Mohammad Shah Gulshan Singh 《Applied Mathematics》 2011年第1期141-144,共4页
Let be a polynomial of degree n having all its zeros in , then for each , , with , Aziz and Ahemad (1996) proved that In this paper, we extend the above inequality to the class of polynomials , having all its zeros in... Let be a polynomial of degree n having all its zeros in , then for each , , with , Aziz and Ahemad (1996) proved that In this paper, we extend the above inequality to the class of polynomials , having all its zeros in , and obtain a generalization as well as refinement of the above result. 展开更多
关键词 Derivative of a POLYNOMIAL integral mean ESTIMATES Complex Domain INEQUALITIES
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Integral Means of Univalent Solution for Fractional Differential Equation
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作者 Rabha W. Ibrahim Maslina Darus 《Applied Mathematics》 2012年第6期590-593,共4页
By employing the Srivastava-Owa fractional operators, we consider a class of fractional differential equation in the unit disk. The existence of the univalent solution is founded by using the Schauder fixed point theo... By employing the Srivastava-Owa fractional operators, we consider a class of fractional differential equation in the unit disk. The existence of the univalent solution is founded by using the Schauder fixed point theorem while the uniqueness is obtained by using the Banach fixed point theorem. Moreover, the integral mean of these solutions is studied by applying the concept of the subordination. 展开更多
关键词 FRACTIONAL CALCULUS SUBORDINATION SUPERORDINATION UNIVALENT SOLUTION FRACTIONAL Differential Equation integral mean
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EXISTENCE OF AREA MINIMIZING TANGENT CONES OF INTEGRAL CURRENTS WITH PRESCRIBED MEAN CURVATURE
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作者 Frank Duzaar(Institut fur Augewandte Mathematik der Universitat Bonn,Beringstr.4.D-53115 Bonn)Martin Fuchs(Universitat des Saarlandes,Fachbereich Mathematik,D-66123 Saarbrucken) 《Acta Mathematica Scientia》 SCIE CSCD 1995年第1期95-102,共8页
Given an integral M-currrent To in Rm+k and a tensor H of type(m.l)on Rn+k with values orthogonal to each of its arguments we proved in a previous peper[3]the sxistence of anintegral m-current T =γ(M,θ.ζ)with bound... Given an integral M-currrent To in Rm+k and a tensor H of type(m.l)on Rn+k with values orthogonal to each of its arguments we proved in a previous peper[3]the sxistence of anintegral m-current T =γ(M,θ.ζ)with boundary T0 and mean curvature vector H by minimizing an appropriate functional on suitable subclasses of the set of all integral currents.In thes paperwe discuss the existence and structure of oriented tangent cones C of T at points x∈spt(T) spt(T),especially we show that C is locally mass minimizing. 展开更多
关键词 integral currents generalized mean curvature tangent cones
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Sharp power-type Heronian and Lehmer means inequalities for the complete elliptic integrals
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作者 ZHAO Tie-hong CHU Yu-ming 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2023年第3期467-474,共8页
In the article,we prove that the inequalities H_(p)(K(r);E(r))>π/2;L_(q)(K(r);E(r))>π/2 hold for all r 2(0;1)if and only if p≥3=4 and q≥3=4,where Hp(a;b)and Lq(a;b)are respectively the p-th power-type Heroni... In the article,we prove that the inequalities H_(p)(K(r);E(r))>π/2;L_(q)(K(r);E(r))>π/2 hold for all r 2(0;1)if and only if p≥3=4 and q≥3=4,where Hp(a;b)and Lq(a;b)are respectively the p-th power-type Heronian mean and q-th Lehmer mean of a and b,and K(r)and E(r)are respectively the complete elliptic integrals of the first and second kinds. 展开更多
关键词 power-type Heronian mean Lehmer means complete elliptic integrals
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Failure Mode and Effects Analysis Based on Z-Numbers and the Graded Mean Integration Representation
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作者 Hanhan Zhang Zhihui Xu +1 位作者 Hong Qian Xiaoyan Su 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第2期1005-1019,共15页
Failuremode and effects analysis(FMEA)is a widely used safety assessmentmethod inmany fields.Z-number was previously applied in FMEA since it can take both possibility and reliability of information into consideration... Failuremode and effects analysis(FMEA)is a widely used safety assessmentmethod inmany fields.Z-number was previously applied in FMEA since it can take both possibility and reliability of information into consideration.However,the use of fuzzy weighted mean to integrate Z-valuations may have some drawbacks and is not suitable for some situations.In this paper,an improved method is proposed based on Z-numbers and the graded mean integration representation(GMIR)to deal with the uncertain information in FMEA.First,Z-numbers are constructed based on the evaluations of risk factors O,S,D for each failure mode by different experts.Second,weights of the three risk factors and experts are determined.Third,the integration representations of Z-numbers are obtained by a newmethod based on the GMIRmethod.Finally,risk priorities of the failure modes are derived considering the weights of experts and risk factors.Two examples and a case study are given to show the use of the proposed method and comparison with other methods.The results show that the proposed method is more reasonable,universal and simple in calculation. 展开更多
关键词 Safety assessment FMEA risk priority number Z-number the graded mean integration representation
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Integrated classification method of tight sandstone reservoir based on principal component analysise simulated annealing genetic algorithmefuzzy cluster means
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作者 Bo-Han Wu Ran-Hong Xie +3 位作者 Li-Zhi Xiao Jiang-Feng Guo Guo-Wen Jin Jian-Wei Fu 《Petroleum Science》 SCIE EI CSCD 2023年第5期2747-2758,共12页
In this research,an integrated classification method based on principal component analysis-simulated annealing genetic algorithm-fuzzy cluster means(PCA-SAGA-FCM)was proposed for the unsupervised classification of tig... In this research,an integrated classification method based on principal component analysis-simulated annealing genetic algorithm-fuzzy cluster means(PCA-SAGA-FCM)was proposed for the unsupervised classification of tight sandstone reservoirs which lack the prior information and core experiments.A variety of evaluation parameters were selected,including lithology characteristic parameters,poro-permeability quality characteristic parameters,engineering quality characteristic parameters,and pore structure characteristic parameters.The PCA was used to reduce the dimension of the evaluation pa-rameters,and the low-dimensional data was used as input.The unsupervised reservoir classification of tight sandstone reservoir was carried out by the SAGA-FCM,the characteristics of reservoir at different categories were analyzed and compared with the lithological profiles.The analysis results of numerical simulation and actual logging data show that:1)compared with FCM algorithm,SAGA-FCM has stronger stability and higher accuracy;2)the proposed method can cluster the reservoir flexibly and effectively according to the degree of membership;3)the results of reservoir integrated classification match well with the lithologic profle,which demonstrates the reliability of the classification method. 展开更多
关键词 Tight sandstone integrated reservoir classification Principal component analysis Simulated annealing genetic algorithm Fuzzy cluster means
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APPROXIMATION OF SPHERICAL MEANS OF MULTIPLE FOURIER INTEGRALS AND FOURIER SERIES ON SET OF FULL MEASURE
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作者 Wang Shiming Zhejiang Institute of Technology, China Math. Section Dept. of Basic Courses Zhejiang Institute of Technology, Hangzhou, 310014, China 《Analysis in Theory and Applications》 1994年第2期17-23,共7页
In this paper we consider the approximation for functions in some subspaces of L^2 by spherical means of their Fourier integrals and Fourier series on set of full measure. Two main theorems are obtained.
关键词 SET Th Pro APPROXIMATION OF SPHERICAL meanS OF MULTIPLE FOURIER integrALS AND FOURIER SERIES ON SET OF FULL MEASURE WANG
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ON THE LOCALIZATION AND CONVERGENCE OF MULTIPLE FOURIER INTEGRAL BY BOCHNER-RIESZ MEANS
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作者 Yu Maohe Kunming Hydropower Scientific Research Institute, China 《Analysis in Theory and Applications》 1993年第2期37-49,共13页
In this paper we consider lim _(R-) B_R^(f,x_0), in one case that f_x_0 (t) is a ABMV function on [0, ∞], and in another case that f∈L_(m-1)~1(R~) and x^k/~kf∈BV(R) when |k| = m-1 and f(x) = 0 when |x -x_0|<δ f... In this paper we consider lim _(R-) B_R^(f,x_0), in one case that f_x_0 (t) is a ABMV function on [0, ∞], and in another case that f∈L_(m-1)~1(R~) and x^k/~kf∈BV(R) when |k| = m-1 and f(x) = 0 when |x -x_0|<δ for some δ>0. Our theormes improve the results of Pan Wenjie ([1]). 展开更多
关键词 LIM ON THE LOCALIZATION AND CONVERGENCE OF MULTIPLE FOURIER integrAL BY BOCHNER-RIESZ meanS
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Numerical Solution of Mean-Square Approximation Problem of Real Nonnegative Function by the Modulus of Double Fourier Integral 被引量:1
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作者 Petro Savenko Myroslava Tkach 《Applied Mathematics》 2011年第9期1076-1090,共15页
A nonlinear problem of mean-square approximation of a real nonnegative continuous function with respect to two variables by the modulus of double Fourier integral dependent on two real parameters with use of the smoot... A nonlinear problem of mean-square approximation of a real nonnegative continuous function with respect to two variables by the modulus of double Fourier integral dependent on two real parameters with use of the smoothing functional is studied. Finding the optimal solutions of this problem is reduced to solution of the Hammerstein type two-dimensional nonlinear integral equation. The numerical algorithms to find the branching lines and branching-off solutions of this equation are constructed and justified. Numerical examples are presented. 展开更多
关键词 mean-Square Approximation Discrete FOURIER Transform TWO-DIMENSIONAL NONLINEAR integral Equation NONUNIQUENESS and Branching of Solutions TWO-DIMENSIONAL NONLINEAR Spectral Problem
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A Study on Internet Buzzwords in the Last Four Years Based on Conceptual Integration Theory
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作者 SUN Yuan-ting GAO Wen-cheng 《Journal of Literature and Art Studies》 2024年第8期711-717,共7页
Internet buzzwords,as distinct forms of language,consist of short sentences yet carry rich meanings and spread rapidly.To better study this intriguing and unique linguistic phenomenon,this paper employed conceptual in... Internet buzzwords,as distinct forms of language,consist of short sentences yet carry rich meanings and spread rapidly.To better study this intriguing and unique linguistic phenomenon,this paper employed conceptual integration theory for its powerful explanatory capabilities to analyze the origins,composition,and emergence of meanings of internet buzzwords over the past four years.These 40 internet buzzwords can be categorized into five types:semantic derivation,generalization,abbreviation,metonymy,and compounding.Furthermore,this paper conducted cognitive analysis from different conceptual integration network perspectives,elucidating specific cognitive operations involved in the construction of meanings and revealing the emergence process of layered meanings in recent internet buzzwords over the past four years. 展开更多
关键词 conceptual integration theory internet buzzwords meaning construction mental space
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基于K-means的水下控制系统集成测试风险分析 被引量:1
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作者 陈泽峰 李华山 +2 位作者 张宪阵 孙广斌 李海寿 《中国海洋平台》 2024年第1期45-50,共6页
采用危险源辨识分析(HAZID)工具对南海某水下控制系统集成测试进行风险识别,研究水下电力和通信设备的联合测试等过程存在的风险,针对HAZID技术识别的测试风险,定义风险的3个指标,包括风险发生可能性、风险后果严重程度和风险预防控制能... 采用危险源辨识分析(HAZID)工具对南海某水下控制系统集成测试进行风险识别,研究水下电力和通信设备的联合测试等过程存在的风险,针对HAZID技术识别的测试风险,定义风险的3个指标,包括风险发生可能性、风险后果严重程度和风险预防控制能力,将风险进行K-means聚类分析,采用SPSS软件将风险分为重大风险、高风险、中风险、低风险等4个聚类等级,识别4类共21个测试风险。在实际运用中,该方法可为水下控制系统集成测试风险制定有针对性的措施,可高效、科学和系统地指导水下控制系统集成测试工作开展。 展开更多
关键词 水下控制系统 集成测试 风险分析 HAZID K-meanS 聚类 轮廓系数
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光储充检放智能电站K-means聚类能效计量检测方法
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作者 张杰梁 《电工技术》 2024年第18期80-82,共3页
光伏出力具有较强的不确定性和随机性,降低了光储充检放一体化能效计量检测性能。为此,在随机采样模式下,提出光储充检放智能电站能效计量检测方法。首先分析光储充检放智能电站的拓扑结构;其次采用K-means聚类算法聚类处理光伏出力数据... 光伏出力具有较强的不确定性和随机性,降低了光储充检放一体化能效计量检测性能。为此,在随机采样模式下,提出光储充检放智能电站能效计量检测方法。首先分析光储充检放智能电站的拓扑结构;其次采用K-means聚类算法聚类处理光伏出力数据,通过Beta分布根据电站拓扑结构生成光伏出力场景,为能效计量检测提供相关数据;最后构建电站能效检测模型,完成光储充检放智能电站能效的计量检测。实验结果表明,所提方法可精准检测光储充检放智能电站的供电功率和充放电功率,能效检测相对偏差小。 展开更多
关键词 光储充检放智能电站 K-meanS聚类算法 BETA分布 光伏出力 能效计量
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基于K-means聚类算法的草莓灌溉策略研究 被引量:13
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作者 李莉 王宏康 +3 位作者 吴勇 陈士旺 王海华 SIGRIMIS N A 《农业机械学报》 EI CAS CSCD 北大核心 2020年第1期295-302,共8页
为进一步提高日光温室封闭式栽培下草莓灌溉水肥利用率,研究了基质含水率和温度影响下的草莓灌溉策略优化方法。采用土壤水分传感器对草莓果期基质含水率进行实时监测,通过对基质含水率随时间变化的规律分析,并结合日平均温度进行K-mean... 为进一步提高日光温室封闭式栽培下草莓灌溉水肥利用率,研究了基质含水率和温度影响下的草莓灌溉策略优化方法。采用土壤水分传感器对草莓果期基质含水率进行实时监测,通过对基质含水率随时间变化的规律分析,并结合日平均温度进行K-means聚类分析,提出一种草莓优化灌溉策略。试验结果表明,灌溉第1阶段基质含水率快速上升,在灌溉结束时达到峰值,每次灌溉基质含水率平均提高21.5个百分点;第2阶段快速下降,在20 min内基质含水率平均下降3.5个百分点;第3阶段变化趋于平稳,在30 min内基质含水率平均下降1.2个百分点。在每个灌溉周期内,含水率呈线性下降趋势,在整个果期内,其斜率随日平均温度的升高逐渐增加,由0.0114增加至0.0365。研究结果表明,根据基质含水率变化和日平均温度区间进行定量灌溉,理论上果期每株草莓仅需要4.51 L水,可节水15.4%,该方法能有效提高水肥利用率,实现节水节肥。 展开更多
关键词 草莓 灌溉策略 K-meanS聚类算法 基质含水率 日平均温度 水肥一体化
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基于多特征信息和直方图相交的改进Meanshift算法
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作者 李晖宙 《舰船电子工程》 2012年第10期38-41,46,共5页
针对Mean-Shift算法仅利用颜色信息并以Bhattacharya系数为相似性度量导致算法准确率较低的问题,提出一种结合颜色和纹理信息并以直方图交集为相似性度量的跟踪算法。首先用局部二元模式算子提取纹理信息,再以对数比加权直方图取代传统... 针对Mean-Shift算法仅利用颜色信息并以Bhattacharya系数为相似性度量导致算法准确率较低的问题,提出一种结合颜色和纹理信息并以直方图交集为相似性度量的跟踪算法。首先用局部二元模式算子提取纹理信息,再以对数比加权直方图取代传统直方图构建目标和候选目标模型,然后根据场景自适应地综合两类特征并通过Mean-Shift算法获得目标的初略位置,最后以直方图交集作为相似性度量并用Powell方法求其极值作为目标在当前帧中位置的估计。实验表明,该算法不仅能增强跟踪的准确性,而且对光照弱、目标与背景颜色近似等情况也有较好的鲁棒性。 展开更多
关键词 目标跟踪 mean-SHIFT算法 多特征融合 直方图交集 Powell方法
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一种改进BP神经网络的K-means算法 被引量:4
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作者 王伟 储泽楠 +1 位作者 张修太 韩毅 《电子器件》 CAS 北大核心 2020年第2期380-385,共6页
针对聚类算法K-means在聚类的过程中,出现数据的属性缺失造成聚类的精确度下降等问题,提出了一种改进BP神经网络的BPK-means算法。该算法首先根据BP神经网络对缺失的属性值进行预测,补全缺失的数据,极大的提高了数据的完整性和可靠性;... 针对聚类算法K-means在聚类的过程中,出现数据的属性缺失造成聚类的精确度下降等问题,提出了一种改进BP神经网络的BPK-means算法。该算法首先根据BP神经网络对缺失的属性值进行预测,补全缺失的数据,极大的提高了数据的完整性和可靠性;然后对异常的数据进行去噪处理;最后通过K-means算法对修复后的数据进行聚类。通过理论验证和实验结果都表明所提出的方法比原始的算法精确度有很大提高。 展开更多
关键词 BP神经网络 属性缺失 K-meanS 降噪处理 数据完整性
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基于K-means聚类技术改进的多线性蒙特卡洛概率能流算法 被引量:18
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作者 靳康萌 张沛 +1 位作者 邓晓洋 谢桦 《电网技术》 EI CSCD 北大核心 2019年第1期65-73,共9页
可再生能源的间歇性出力以及负荷的波动给综合能源系统(integrated energy systems,IES)引入了大量不确定性因素。提出了一种基于K-means聚类技术改进的多线性蒙特卡洛概率能流计算方法。首先,引入输入随机变量整体灵敏度系数概念,并以... 可再生能源的间歇性出力以及负荷的波动给综合能源系统(integrated energy systems,IES)引入了大量不确定性因素。提出了一种基于K-means聚类技术改进的多线性蒙特卡洛概率能流计算方法。首先,引入输入随机变量整体灵敏度系数概念,并以权重系数的形式修正输入随机变量样本,改进K-means聚类效果,确保各聚类簇均具有较小的波动范围。然后,采用多线性化求解思路进行概率能流计算,即对聚类中心进行确定性能流计算,而各聚类簇中输入随机变量样本利用同一簇聚类中心处得到的状态变量和雅可比矩阵进行线性化能流求解,从而减少了迭代过程,提高计算效率。以IEEE57节点电力系统和14节点天然气网络构成的IES为算例,验证了所提方法比传统蒙特卡洛法具有更高的计算效率,相比现有多线性蒙特卡洛算法具有更高的准确性和计算效率。 展开更多
关键词 综合能源系统 概率能流 K-meanS聚类算法 多线性蒙特卡洛模拟
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基于Mean Shift模型的多粗差探测RAIM算法 被引量:3
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作者 刘一 周威 +2 位作者 金际航 边少锋 谷守周 《系统工程与电子技术》 EI CSCD 北大核心 2022年第2期644-650,共7页
针对当前接收机自主完备性监测(receiver autonomous integrity monitoring,RAIM)算法中存在多粗差探测识别能力较弱、计算效率不足等问题,提出一种基于Mean Shift(MS)模型的多粗差探测RAIM算法。首先利用QR奇偶检校法构建样本数据集和Q... 针对当前接收机自主完备性监测(receiver autonomous integrity monitoring,RAIM)算法中存在多粗差探测识别能力较弱、计算效率不足等问题,提出一种基于Mean Shift(MS)模型的多粗差探测RAIM算法。首先利用QR奇偶检校法构建样本数据集和QR检验向量;其次基于MS模型估计样本密度中心,并以此作为MS检校向量,使用观测向量与MS检校向量的距离来评价观测值可靠程度,从而确定异常观测卫星;最后联合观测向量、MS和QR检校向量构建基于距离关系的权系数函数,对多个异常观测进行处理。实验结果表明,基于MS检校向量的粗差判别方法在多粗差存在的情况下,具有更灵敏的粗差识别能力;相比最小二乘残差法,新型RAIM算法改善了多粗差探测识别能力和计算效率,可有效提高多系统融合单点定位的可靠性。 展开更多
关键词 接收机自主完好性监测 多粗差 均值漂移 多全球导航卫星系统 单点定位
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