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Explicit solution of diffusion master equation under the action of linear resonance force via the thermal entangled state representation 被引量:3
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作者 姚飞 王继锁 徐天牛 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第7期98-101,共4页
Using the well-behaved features of the thermal entangled state representation, we solve the diffusion master equation under the action of a linear resonance force, and then obtain the infinitive operator-sum represent... Using the well-behaved features of the thermal entangled state representation, we solve the diffusion master equation under the action of a linear resonance force, and then obtain the infinitive operator-sum representation of the density operator. This approach may also be effective for treating other master equations. Moreover, we find that the initial pure coherent state evolves into a mixed thermal state after passing through the diffusion process under the action of the linear resonance force. 展开更多
关键词 diffusion process linear resonance force thermal state representation infinitive operator-sum representation
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Tensor-Product Representation for Switched Linear Systems
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作者 Dengyin Jiang Lisheng Hu 《Journal of Applied Mathematics and Physics》 2015年第3期322-337,共16页
This paper presents the method for the construction of tensor-product representation for multivariate switched linear systems, based on a suitable tensor-product representation of vectors and matrices. We obtain a rep... This paper presents the method for the construction of tensor-product representation for multivariate switched linear systems, based on a suitable tensor-product representation of vectors and matrices. We obtain a representation theorem for multivariate switched linear systems. The stability properties of the tensor-product representation are investigated in depth, achieving the important result that any stable switched systems can be constructed a stable tensor-product representation of finite dimension. It is shown that the tensor-product representation provides a high level framework for describing the dynamic behavior. The interpretation of expressions within the tensor-product representation framework leads to enhanced conceptual and physical understanding of switched linear systems dynamic behavior. 展开更多
关键词 SWITCHED linear Systems Tensor-Product representation STABILITY
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Real-Valued Discrete Gabor Transform of Linear Time-Varying Systems: Exact Representation and Approximation
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作者 陶亮 罗斌 《Journal of Electronic Science and Technology of China》 2005年第1期1-5,共5页
An efficient algorithm for the representation and approximation of linear time-varying systems is presented via the fast real-valued discrete Gabor transform. Compared with the existing algorithm based on the traditio... An efficient algorithm for the representation and approximation of linear time-varying systems is presented via the fast real-valued discrete Gabor transform. Compared with the existing algorithm based on the traditional complex-valued discrete Gabor transform, the proposed algorithm runs faster, can more easily be implemented in software or hardware, and leads to a more compact representation. Simulation results are given for demonstration. 展开更多
关键词 Gabor transforms real-valued discrete Gabor transforms kernel representation linear time-varying systems
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Longwall mining automation horizon control:Coal seam gradient identification using piecewise linear fitting 被引量:3
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作者 Shibo Wang Shijia Wang 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2022年第4期821-829,共9页
Horizon control,maintaining the alignment of the shearer's exploitation gradient with the coal seam gradient,is a key technique in longwall mining automation.To identify the coal seam gradient,a geological model o... Horizon control,maintaining the alignment of the shearer's exploitation gradient with the coal seam gradient,is a key technique in longwall mining automation.To identify the coal seam gradient,a geological model of the coal seam was constructed using in-seam seismic surveying technology.By synthesizing the control resolution of the range arm and the geometric characteristics of the coal seam,a gradient identification method based on piecewise linear representation(PLR)is proposed.To achieve the maximum exploitation rate within the shearer's capacity,the control resolution of the range arm is selected as the threshold parameter of PLR.The control resolution significantly influenced the number of line segments and the fitting error.With the decrease of the control resolution from 0.01 to 0.02 m,the number of line segments decreased from 65 to 15,which was beneficial to horizon control.However,the average fitting error increased from 0.055 to 0.14 m,which would induce a decrease in the exploitation rate.To avoid significant deviation between the cutting range and the coal seam,the control resolution of the range arm must be lower than 0.02 m.In a field test,the automated horizon control of the longwall face was realized by coal seam gradient identification. 展开更多
关键词 Coal seam gradient Exploitation gradient Geological model Horizon control Piecewise linear representation
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Dual optimization image repair algorithm based on linear structure and optimal texture 被引量:1
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作者 陈炳权 刘宏立 《Journal of Central South University》 SCIE EI CAS 2014年第6期2315-2323,共9页
The performances of repaired image depend on the local information in the repaired area and the consistency between the repair directions with structural content.Image repair algorithm with texture information perform... The performances of repaired image depend on the local information in the repaired area and the consistency between the repair directions with structural content.Image repair algorithm with texture information performs well in repairing seriously damaged images,but it has bad performances when the images have the abundant structure information.The dual optimization image repair algorithm based on the linear structure and the optimal texture is proposed.The algorithm uses the double-constraint sparse model to reconstruct the missed information in large area in order to improve the clarity of repaired images.After adopting the preference of Criminisi priority,the image repair algorithm of self-similarity characteristics is proposed to improve the fault and fuzzy distortion phenomena in the repaired image.The results show that the proposed algorithm has more clarity in the image texture and structure and better effectiveness,and the peak signal-to-noise ratio of the repaired images by proposed algorithm is superior to that by other algorithms. 展开更多
关键词 image restoration linear structure texture information ITERATION sparse representation
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3D Object Recognition Based on Linear Lie Algebra Model
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作者 李方兴 吴平东 +1 位作者 孙华飞 彭林玉 《Journal of Beijing Institute of Technology》 EI CAS 2009年第1期46-50,共5页
A surface model called the fibre bundle model and a 3D object model based on linear Lie algebra model are proposed. Then an algorithm of 3D object recognition using the linear Lie algebra models is presented. It is a ... A surface model called the fibre bundle model and a 3D object model based on linear Lie algebra model are proposed. Then an algorithm of 3D object recognition using the linear Lie algebra models is presented. It is a convenient recognition method for the objects which are symmetric about some axis. By using the presented algorithm, the representation matrices of the fibre or the base curve from only finite points of the linear Lie algebra model can be obtained. At last some recognition results of practicalities are given. 展开更多
关键词 linear Lie algebra RECOGNITION representation matrix
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Algebraic Techniques for Linear Equations over Quaternions and Split Quaternions: A Unified Approach in Quaternionic and Split Quaternionic Mechanics
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作者 Gang Wang Zhenwei Guo +1 位作者 Dong Zhang Tongsong Jiang 《Journal of Applied Mathematics and Physics》 2019年第8期1718-1731,共14页
This paper aims to present, in a unified manner, algebraic techniques for linear equations which are valid on both the algebras of quaternions and split quaternions. This paper, introduces a concept of v-quaternion, s... This paper aims to present, in a unified manner, algebraic techniques for linear equations which are valid on both the algebras of quaternions and split quaternions. This paper, introduces a concept of v-quaternion, studies the problem of v-quaternionic linear equations by means of a complex representation and a real representation of v-quaternion matrices, and gives two algebraic methods for solving v-quaternionic linear equations. This paper also gives a unification of algebraic techniques for quaternionic and split quaternionic linear equations in quaternionic and split quaternionic mechanics. 展开更多
关键词 V-Quaternion Complex representation Real representation linear EQUATIONS QUATERNION SPLIT QUATERNION
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The identification algorithm for commensurate order linear time-invariant fractional systems
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作者 王振滨 曹广益 朱新坚 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2005年第5期576-580,共5页
An efficient identification algorithm is given for commensurate order linear time-invariant fractional systems. This algorithm can identify not only model coefficients of the system, but also its differential order at... An efficient identification algorithm is given for commensurate order linear time-invariant fractional systems. This algorithm can identify not only model coefficients of the system, but also its differential order at the same time. The basic idea is to change the system matrix into a diagonal one through basis transformation. This makes it possible to turn the system’s input-output relationships into the summation of several simple subsystems, and after the identification of these subsystems, the whole identification system is obtained which is algebraically equivalent to the former system. Finally an identification example verifies the effectiveness of the method previously mentioned. 展开更多
关键词 fractional systems COMMENSURATE linear time-invariant state-space representation system identification
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再现与幻觉的线性图像——重塑电影影像的本体 被引量:2
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作者 李洋 《艺术传播研究》 2025年第1期4-13,共10页
电影影像的本质可以尝试从图像性的角度重新阐释,以强调再现与幻觉之间的二元张力。电影影像既源于摄影图像的再现性,又通过光学和认知机制创造出运动的幻觉。电影不是对现实的简单记录,而是要通过幻觉让观众体验运动。不同导演对再现... 电影影像的本质可以尝试从图像性的角度重新阐释,以强调再现与幻觉之间的二元张力。电影影像既源于摄影图像的再现性,又通过光学和认知机制创造出运动的幻觉。电影不是对现实的简单记录,而是要通过幻觉让观众体验运动。不同导演对再现与幻觉的不同理解,形成了对电影的不同认知。电影的特性使其成为一种“理性的魔法”,既记录现实,又创造幻觉。最终,电影影像在时间的线性编码中实现了再现与幻觉的统一。 展开更多
关键词 电影影像 再现 幻觉 线性图像 无我世界
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线性矩法在分布未知条件下的随机结构抗震可靠度分析
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作者 吴罗成 张龙文 曾梦澜 《振动工程学报》 北大核心 2025年第1期180-190,共11页
在工程结构领域,由于数据不足,结构参数的分布通常未知,这成为结构可靠性分析中常见而复杂的挑战。在结构参数分布未知的情况下,本文提出了随机结构抗震可靠度分析的线性矩法。构造了仅由两个基本随机变量描述的随机动力系统:(1)基于结... 在工程结构领域,由于数据不足,结构参数的分布通常未知,这成为结构可靠性分析中常见而复杂的挑战。在结构参数分布未知的情况下,本文提出了随机结构抗震可靠度分析的线性矩法。构造了仅由两个基本随机变量描述的随机动力系统:(1)基于结构随机参数的前四阶线性矩,借助标准正态分布随机变量的随机函数表达,将结构参数的随机变量表示为仅有一个基本随机变量的一元三次多项式;(2)利用一个基本随机变量的随机函数‐谱表示模型描述非平稳地震动过程。在此基础上,根据数论方法确定两个基本随机变量的代表点集,进行时程分析并计算结构响应极值,进而计算确定界限下功能函数的样本及其线性矩;利用功能函数的前四阶线性矩求解三次多项式转换系数;并根据一元三次方程根的求解,建立基于线性矩的结构抗震可靠指标表达式。以结构参数分布未知的非线性单自由度为例说明了本文方法的应用,同时与Monte Carlo模拟结果对比,验证了本文方法的精确性。 展开更多
关键词 抗震可靠度 随机结构 线性矩 分布未知 随机函数-谱表示
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基于动态线性分段表示的钻进参数围岩分级特征提取方法 被引量:1
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作者 何永义 王明年 +5 位作者 凌学鹏 易文豪 夏覃永 李泽星 童建军 赵思光 《中国铁道科学》 北大核心 2025年第1期96-106,共11页
依托来自宜昌—郑万高铁联络线隧道工程的1 765份钻进参数样本,在分析钻进参数时序曲线特征的基础上,结合贝叶斯置信区间检验方法、动态线性分段表示方法、卡尔曼滤波方法和线性分段均值处理方法,提出一种基于动态线性分段表示的钻进参... 依托来自宜昌—郑万高铁联络线隧道工程的1 765份钻进参数样本,在分析钻进参数时序曲线特征的基础上,结合贝叶斯置信区间检验方法、动态线性分段表示方法、卡尔曼滤波方法和线性分段均值处理方法,提出一种基于动态线性分段表示的钻进参数围岩分级特征提取方法;对比该方法处理前后掌子面钻进参数样本的离散性和差异性,以及采用该方法处理前后6种不同机器学习算法下的围岩分级模型准确性,验证该方法的应用效果。结果表明:钻进参数时序体现出明显的纵向分段、区间波动和随机离散特征;采用该方法处理后,相同围岩级别下的样本数据标准差平均降低28.72%~82.68%,不同围岩级别下的样本类间距离均值提升66.79%~77.37%,6种机器学习算法下围岩分级模型得到的分级准确率由85.3%~88.8%提高到88.1%~89.9%。作为一种基础数据处理方法,该方法能够避免各种非地质因素对围岩分级精度的影响,较好地体现了钻进参数和围岩质量间的良好响应关系,并提升了具体实践中的围岩质量评价准确性。 展开更多
关键词 隧道 围岩分级 钻进参数 时间序列 动态线性分段表示 贝叶斯置信区间检验 卡尔曼滤波
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基于连续时间表示的炼钢-连铸过程调度建模与求解
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作者 李显昱 黄德先 +1 位作者 尚超 亓鲁刚 《控制工程》 北大核心 2025年第1期148-157,共10页
面向某钢铁企业在炼钢-连铸阶段的复杂生产调度问题,提出了一种基于连续时间表示的调度建模方法。依据炼钢-连铸过程的每个浇次中各炉次的保序性,针对每一台生产设备,将每个炉次的作业开始与结束时间作为决策变量,并根据避免作业冲突的... 面向某钢铁企业在炼钢-连铸阶段的复杂生产调度问题,提出了一种基于连续时间表示的调度建模方法。依据炼钢-连铸过程的每个浇次中各炉次的保序性,针对每一台生产设备,将每个炉次的作业开始与结束时间作为决策变量,并根据避免作业冲突的原则构建约束;同时,定义离散决策变量,保证炉次在同一类生产设备中进行作业的唯一性。最终,调度模型被构建为一个混合整数规划问题,从而便于使用商业求解器高效求解。在同一生产计划中对基于不同时间表示方法的调度模型进行仿真测试,仿真结果表明,所提方法能够在要求的运行时间内得到满足工艺要求的最优决策,在工程应用中具有可行性。 展开更多
关键词 炼钢-连铸过程 连续时间表示 调度优化 混合整数规划
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Real-Time Pricing of Smart Grid Based on Piece-Wise Linear Functions 被引量:4
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作者 Zhihong XU Liangyu GUO +2 位作者 Yan GAO Muhammad HUSSAIN Panhong CHENG 《Journal of Systems Science and Information》 CSCD 2019年第4期295-316,共22页
In a power grid system, utility is a measure of the satisfaction of users’ electricity consumption;cost is a monetary value of electricity generated by the supplier. The utility and cost functions represent the satis... In a power grid system, utility is a measure of the satisfaction of users’ electricity consumption;cost is a monetary value of electricity generated by the supplier. The utility and cost functions represent the satisfaction of different users and the supplier. Quadratic utility, logarithmic utility,and quadratic cost functions are widely used in social welfare maximization models of real-time pricing. These functions are not universal;they have to be discussed in detail for individual models. To overcome this problem, a piece-wise linear utility function and a piece-wise linear cost function with general properties are proposed in this paper. By smoothing the piece-wise linear utility and cost functions, a social welfare maximization model can be transformed into a differentiable convex optimization problem. A dual optimization method is used to solve the smoothed model. Through mathematical deduction and numerical simulations, the rationality of the model and the validity of the algorithm are verified as long as the elastic and cost coefficients take appropriate values. Thus, different user types and the supplier can be determined by selecting different elastic and cost coefficients. 展开更多
关键词 smart grid real-time PRICING piece-wise linear UTILITY and COST FUNCTIONS dual optimization method
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结合多模态筛选和联合协同表示的SAR图像目标识别方法
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作者 李瑞芳 许洋洋 +1 位作者 杨若璞 郭光立 《火力与指挥控制》 北大核心 2025年第10期81-87,共7页
针对合成孔径雷达目标识别问题,为提升特征和分类器的有效性,在特征提取阶段,基于二维经验模态分解获取SAR图像多层次描述,即二维内蕴模态函数;以原始图像为参照,采用非线性相关信息熵筛选最优的BIMF子集。进入分类阶段,采用联合协同表... 针对合成孔径雷达目标识别问题,为提升特征和分类器的有效性,在特征提取阶段,基于二维经验模态分解获取SAR图像多层次描述,即二维内蕴模态函数;以原始图像为参照,采用非线性相关信息熵筛选最优的BIMF子集。进入分类阶段,采用联合协同表示对选取的BIMF子集进行编码表征,获取最优重构条件下的线性表示系数矢量。根据不同类别的编码误差,确定测试样本的目标归属。以MSTAR数据集为基础设置实验条件,经对比验证证明了提出方法的有效性。 展开更多
关键词 合成孔径雷达 目标识别 二维经验模态分解 非线性相关信息熵 联合协同表示
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基于角度关键点和转向点的时间序列趋势特征提取 被引量:2
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作者 刘冰珂 任芮彬 王溪 《计算机系统应用》 2025年第1期285-293,共9页
时间序列分段线性表示算法利用时间序列的趋势变化特征,用序列中较少点来表示整个时间序列.但是大多算法主要关注局部序列点信息,很少关注全局数据,且部分算法只关注算法在数据集上的拟合,很少应用到分类问题中.针对上述问题,本文提出... 时间序列分段线性表示算法利用时间序列的趋势变化特征,用序列中较少点来表示整个时间序列.但是大多算法主要关注局部序列点信息,很少关注全局数据,且部分算法只关注算法在数据集上的拟合,很少应用到分类问题中.针对上述问题,本文提出了基于角度关键点和转向点的时间序列趋势特征提取算法,首先,该算法根据序列数据的角度变化值来选择角度显著点,然后基于角度关键点的基础上再提取转向点,根据分段的要求,判断是否进行插值操作,从而得到符合要求的分段点序列.本文在模拟数据和40个公开数据集上进行拟合和分类实验,实验结果表明,本文算法相较于分段聚合近似PAA、自底向下TD、自顶向上BU、基于拐点FFTO、基于转折点和趋势段Trend、基于趋势转折点ITTP等算法,在模拟数据集拟合效果更好;在UCR公开数据集平均拟合误差为1.165;分类准确性同Keogh团队公布的DTW-1NN算法高出2.8%. 展开更多
关键词 角度关键点 转向点 时间序列 分段线性表示 趋势特征
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Heisenberg李代数拟型心的矩阵表示
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作者 朱悦 杨如惠 郑克礼 《哈尔滨商业大学学报(自然科学版)》 2025年第3期352-355,共4页
Heisenberg代数作为一类重要的李代数,多年来数学家们探究其各种性质,包括型心结构,自同构与拟自同构,而拟型心亦为探究李代数结构中重要的一环.讨论了(2n+1)维Heisenberg李代数的拟型心,依据拟型心的定义,将其作用在(2n+1)维Heisenber... Heisenberg代数作为一类重要的李代数,多年来数学家们探究其各种性质,包括型心结构,自同构与拟自同构,而拟型心亦为探究李代数结构中重要的一环.讨论了(2n+1)维Heisenberg李代数的拟型心,依据拟型心的定义,将其作用在(2n+1)维Heisenberg李代数的李括积运算上,结合矩阵的运算,对比矩阵各元素之间的关系,进而确定出(2n+1)维Heisenberg李代数的拟型心矩阵表示. 展开更多
关键词 复李代数 Heisenberg李代数 拟型心 矩阵表示 李括积 线性变换
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Polynomial Splitting Ring and Root Representation of Linear Recurring Sequences Over Z|(p^e)
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作者 戚文峰 周锦君 《Science China Mathematics》 SCIE 1994年第9期1047-1052,共6页
The concept of the splitting ring of the polynomial over ring Z(pe) is introduced and the factomation of polynomials and the properties df polynomial roots are discussed. By using these results and the structure of se... The concept of the splitting ring of the polynomial over ring Z(pe) is introduced and the factomation of polynomials and the properties df polynomial roots are discussed. By using these results and the structure of sequence families, it is shown that the terms of a linear recurring sequence over Z/(pe) may be represented by the roots of its characteristic polynomial and the representation is uniquely determined by the sequence. 展开更多
关键词 SPLITTING RING OVER Z|(p^e) linear recurring sequence ROOT representation of sequences.
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基于线性子空间稀疏表示的遥感图像目标检测
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作者 王君玲 《国外电子测量技术》 2025年第5期42-49,共8页
针对复杂背景下高光谱遥感图像的弱小目标检测效果不佳的问题,提出基于线性子空间稀疏表示的遥感图像目标检测方法。通过低秩分解方法构建可描述高光谱遥感图像空间-光谱信息的图像张量表示,根据高光谱遥感图像张量表示中的光谱信息构... 针对复杂背景下高光谱遥感图像的弱小目标检测效果不佳的问题,提出基于线性子空间稀疏表示的遥感图像目标检测方法。通过低秩分解方法构建可描述高光谱遥感图像空间-光谱信息的图像张量表示,根据高光谱遥感图像张量表示中的光谱信息构建线性子空间模型,使用高光谱遥感图像稀疏表示中的目标字典空间代替线性子空间模型中的子空间,实现最终的弱小目标检测。实验结果表明:所提方法在AVIRIS-NG和Pavia University数据集上,当超像素参数m=0.03 N、n=15时取得最优性能,城市场景AUC(area under curve)0.901,农田检测率95.3%;目标像元数占比达185/200,丰度估计均方根误差仅0.01,显著优于对比方法。不同信噪比测试中,所提方法在5 dB低信噪比下仍保持F1-score 0.81和AUC 0.83,20 dB时分别提升至0.95和0.97,验证了其强鲁棒性。所提方法的目标检测准确度更高,整体应用效果更好。 展开更多
关键词 高光谱遥感图像 张量表示 稀疏表示 线性子空间模型 弱小目标检测
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关于行阶梯形主元列唯一性以及行最简形唯一性的一个注记
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作者 王培颖 谭俊宇 《衡阳师范学院学报》 2025年第3期61-63,共3页
本文通过数学归纳法及反证法,利用行等价矩阵的秩相等,证明了行等价的行阶梯形矩阵的主元列的位置一致,再利用反证法简明地证得了行最简形唯一性,最后说明了行阶梯形主元列唯一性与行最简形唯一性的证明之间的逻辑关系。
关键词 行阶梯形矩阵 行最简形矩阵 线性表示 唯一性
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基于角度分段线性近似和改进密度峰值聚类的户变关系识别
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作者 赵耀 付皖皖 +1 位作者 陈冉 张涛 《电力科学与技术学报》 北大核心 2025年第1期113-125,共13页
为解决因排查效率低、数据更新不及时等因素导致低压配电网户变关系连接形式与实际不符的问题,提出一种基于角度分段线性近似(anglepiecewiselinearrepresentation,APLR)和改进密度峰值聚类(improved clustering by fast search find of... 为解决因排查效率低、数据更新不及时等因素导致低压配电网户变关系连接形式与实际不符的问题,提出一种基于角度分段线性近似(anglepiecewiselinearrepresentation,APLR)和改进密度峰值聚类(improved clustering by fast search find of density peaks,ICFSFDP)相结合的户变关系识别方法。首先,根据电压曲线中相邻线段的角度变化量提取曲线的转折点,利用APLR对曲线进行自适应降维重构;随后,使用ICFSFDP算法对降维数据组展开聚类分析,在决策图中由拟合函数与坐标轴围成面积的最小值得到最优类簇数目,进而得到聚类和非聚类中心用户;最后,使用动态时间弯曲(dynamic time warping,DTW)距离计算聚类和非聚类中心用户之间的距离相似度,进而得到户变关系。将所提方法应用于模拟和真实数据中,均可证实所提方法的有效性。算例分析结果表明:该方法能够对时间间隔不同、不等维的序列进行分析,且不需要人为设定聚类算法的参数,户变关系识别准确率高。 展开更多
关键词 配电网 户变关系 改进分段线性近似 动态时间弯曲距离 最小面积法 密度峰值聚类
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