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统计递归集中的鞅性质
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作者 胡迪鹤 《武汉大学学报(自然科学版)》 CSCD 1999年第3期257-260,共4页
主要研究了统计递归集中一些相关的随机过程是否具有鞅性质,给出了一些充分条件以保证:生成统计递归集的统计压缩算子的 Lipschitz 系数和所构成的随机过程具有鞅性质
关键词 统计递归集 统计压缩算子 随机过程
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变压器超高频局部放电自动识别系统 被引量:17
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作者 王国利 袁鹏 +3 位作者 单平 郑毅 郝艳捧 李彦明 《电工电能新技术》 CSCD 2003年第1期9-13,F004,共6页
本文研制了一套变压器超高频局部放电自动识别系统,详细介绍了系统的硬件和软件实现。硬件主要包括超高频天线和频谱分析仪,软件由信号采集、统计谱图生成、统计算子(指纹)计算、用基于遗传算法的神经网络进行模式识别四部分组成。在实... 本文研制了一套变压器超高频局部放电自动识别系统,详细介绍了系统的硬件和软件实现。硬件主要包括超高频天线和频谱分析仪,软件由信号采集、统计谱图生成、统计算子(指纹)计算、用基于遗传算法的神经网络进行模式识别四部分组成。在实验室中对变压器典型局放模型进行实验,结果表明,该系统可以很好地用于提取高频(中心频率在500~1000MHz之间可调)窄带(带宽5MHz)时域放电信号,并且具有强大的数据处理、显示、分析、识别等功能,从而为变压器超高频局部放电检测以及绝缘状态评估提供了丰富的信息。 展开更多
关键词 变压器 超高频局部放电 自动识别系统 放电谱图 统计算子 模式识别 故障诊断 神经网络
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基于直流局部放电的高压储能电容器缺陷的模糊识别 被引量:10
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作者 王鹏 吴广宁 +1 位作者 张依强 张血琴 《高压电器》 CAS CSCD 北大核心 2011年第3期64-68,共5页
为提高脉冲功率系统中高压储能电容器的可靠性,笔者利用直流下局部放电对电容器进行缺陷检测,得到直流局部放电测量数据的统计谱图,提出基于模糊数学理论识别电容器缺陷类型的方法。首先从22个统计算子中挑选出12个具有典型特征的统计... 为提高脉冲功率系统中高压储能电容器的可靠性,笔者利用直流下局部放电对电容器进行缺陷检测,得到直流局部放电测量数据的统计谱图,提出基于模糊数学理论识别电容器缺陷类型的方法。首先从22个统计算子中挑选出12个具有典型特征的统计算子组成特征向量,然后通过内部缺陷、接触缺陷、重叠缺陷、油质缺陷4种典型缺陷的测量,计算出每种缺陷特征向量的正态分布隶属函数。最后对未知缺陷类型的电容器进行了模糊检测和解剖验证,对含有可视气泡已知缺陷的电容器进行了检测和模糊识别,证明了系统的实用性,系统可用于脉冲功率系统组装前电容器的可靠性检测。 展开更多
关键词 绝缘缺陷 模糊数学 直流局部放电 模式识别 统计算子
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基于ARM的电力变压器UHF局部放电监测系统 被引量:3
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作者 邓本再 代凤龙 邓丰 《高压电器》 CAS CSCD 北大核心 2008年第5期477-479,共3页
为了无失真地采集超高频检测中所需的有用信号,笔者介绍了一种利用混频原理将电力变压器UHF局部放电信号进行降频变换,较好地采用ARM微处理器设计了一款现场信号调理与采集系统,在μC/OS-Ⅱ操作系统基础上编写用户软件对信号进行处理和... 为了无失真地采集超高频检测中所需的有用信号,笔者介绍了一种利用混频原理将电力变压器UHF局部放电信号进行降频变换,较好地采用ARM微处理器设计了一款现场信号调理与采集系统,在μC/OS-Ⅱ操作系统基础上编写用户软件对信号进行处理和运算,提取了局部放电信号的各类相位分布谱图和统计算子。实验结果表明,笔者设计的基于混频技术的信号调理单元,很好地达到了UHF窄带时域信号的降频变换作用,为局部放电模式识别提供了各种可靠真实的特征参数。 展开更多
关键词 局部放电 UHF ARM 数据采集 统计算子
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一种新的二维非线性提升小波变换方法 被引量:1
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作者 李宏亮 刘贵忠 +2 位作者 侯兴松 李永利 张宗平 《电子学报》 EI CAS CSCD 北大核心 2003年第1期21-24,共4页
根据图像的统计信息 ,本文构造了一种新的非线性算子即统计算子 ,提出了基于该算子的一种新的非线性提升小波分析方法 .使图像经过该方法变换以后 ,在无量化失真的前提下 ,以较大概率取得零高频系数 .本文将该方法与现存文献中所提出的... 根据图像的统计信息 ,本文构造了一种新的非线性算子即统计算子 ,提出了基于该算子的一种新的非线性提升小波分析方法 .使图像经过该方法变换以后 ,在无量化失真的前提下 ,以较大概率取得零高频系数 .本文将该方法与现存文献中所提出的非线性形态学小波等分析方法 ,进行了标准图像的测试分析 ,实验结果显示 ,利用本文所提出的基于统计算子的提升小波分析的方法所得到的高频子带的熵都低于其它几种非线性小波变换 ,取得了很好的分析结果 . 展开更多
关键词 非线性小波变换 统计算子 无失真图像编码 形态学小波
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基于MRF的统计预测提升算子的构造与应用研究
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作者 李宏亮 刘贵忠 +1 位作者 李永利 侯兴松 《中国科学(E辑)》 CSCD 北大核心 2003年第12期1107-1114,共8页
根据图像的统计信息,在Markov随机场(MRF)的理论基础上,构造了一种新的非线性算子即统计算子,提出了基于该算子的一种非线性提升小波分析方法.并根据MRF的条件概率分布,在理论上证明了采用基于统计算子的非线性提升小波变换可使图像变换... 根据图像的统计信息,在Markov随机场(MRF)的理论基础上,构造了一种新的非线性算子即统计算子,提出了基于该算子的一种非线性提升小波分析方法.并根据MRF的条件概率分布,在理论上证明了采用基于统计算子的非线性提升小波变换可使图像变换后,在无量化失真的前提下,提高高频子带的零高频系数.将该方法与现有的几种非线性形态学小波分析方法以及S+P变换和JPEG2000采用的5/3和9/7线性提升小波变换进行了不同图像的测试分析,实验结果显示,利用这种基于统计算子的提升小波分析方法对医学图像和混合文档图像变换后可取得较低的加权熵. 展开更多
关键词 MRF 统计预测提升算子 非线性小波变换 无失真图像编码 MARKOV随机场 统计算子 图像压缩编码
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一种新的空谱联合探测高光谱影像目标探测算法 被引量:8
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作者 王彩玲 王洪伟 +3 位作者 胡炳樑 温佳 徐君 李湘眷 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2016年第4期1163-1169,共7页
高光谱遥感影像不但具有高分辨率的空间信息还包含连续的光谱信息,因此在目标探测领域具有独特的应用优势。传统的高光谱遥感影像目标探测侧重于光谱信息的应用,形成了确定性算法和统计学算法。确定性算法通过计算目标光谱与待检测光谱... 高光谱遥感影像不但具有高分辨率的空间信息还包含连续的光谱信息,因此在目标探测领域具有独特的应用优势。传统的高光谱遥感影像目标探测侧重于光谱信息的应用,形成了确定性算法和统计学算法。确定性算法通过计算目标光谱与待检测光谱之间的距离来查找目标,不能检测亚像素目标,而且容易受到噪声的影响;统计学目标检测计算背景统计特性,通过探测异常点来检测目标,可以检测亚像素目标和小目标,但容易受到目标尺寸的影响,不能很好的检测大目标。随着高光谱遥感影像的空间分辨率的增加,探测目标已有亚像素目标逐步转换为单像素及多像素目标,此时,在高光谱图像中,相同类别的地物在空间分布上呈现聚类特性,因此,在利用高光谱遥感影像进行目标探测时,需要将其空间信息融入算法中。将空间特征引入传统目标探测算法。提出了一种新的空谱结合的高光谱目标探测算法,将传统的基于统计的目标探测算子与空域邻域聚类算法相结合,首先利用目标探测算子将影像划分为潜在目标区域与背景区域;通过计算潜在目标区域的质心,以质心为中心进行邻域聚类,剔除潜在目标区域中的背景区域,通过迭代计算获取最终目标探测结果。传统的基于统计的目标探测算子,将整个探测区域定义为背景区域,实现对背景区域的统计特征提取,而该方法将背景区域与潜在目标区域分离,剔除了目标区域对背景区域的统计干扰。将本算子与传统的约束能量最小化算子和自适应余弦探测算子进行分析比较可知,该算子的大目标探测性能优于传统的统计算子。 展开更多
关键词 目标探测 空谱联合算子 高光谱影像处理 邻域聚类 统计算子
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随机次自相似集的表示 被引量:2
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作者 胡迪鹤 《数学杂志》 CSCD 北大核心 2001年第4期361-367,共7页
本文引进了随机次自相似集与随机推移集的概念 ,讨论了随机次自相似集的结构 ,并证明了任一随机集是随机次自相似集的充分必要条件是
关键词 次自相似集 随机次自相似集 随机推移集 统计压缩算子 统计相似压缩算子 分形理论 充要条件
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Bhattacharyya不等式在Hilbert空间的推广
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作者 陈萍 《南京理工大学学报》 CAS CSCD 1995年第5期421-424,共4页
该文在Hilbert空间算子统计模型中,导出了用算子迹表示的Bhat-tacharyya不等式,并通过算子方程给出了达到Bh下界的算子值估计量所应满足的条件。
关键词 参数估计 希尔伯特空间 B不等式 算子统计模型
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人工神经网络在局部放电模式识别中的应用
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作者 代超 《机电信息》 2009年第24期141-142,共2页
探讨了放电模型的神经网络识别,研究了以统计算子为输入量的发电机局部放电信号的神经网络模式识别,通过神经网络模型的建立及学习,分析如何识别几种典型局部放电模型信号,为发电机绝缘故障类型的判别提供了理论基础。
关键词 人工神经网络 局部放电 统计算子
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General Quantum Interference Principle and Duality Computer 被引量:33
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作者 LONG Gui-Lu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第5期825-844,共20页
In this article, we propose a general principle of quantum interference for quantum system, and based on this we propose a new type of computing machine, the duality computer, that may outperform in principle both cla... In this article, we propose a general principle of quantum interference for quantum system, and based on this we propose a new type of computing machine, the duality computer, that may outperform in principle both classical computer and the quantum computer. According to the general principle of quantum interference, the very essence of quantum interference is the interference of the sub-waves of the quantum system itself A quantum system considered here can be any quantum system: a single microscopic particle, a composite quantum system such as an atom or a molecule, or a loose collection of a few quantum objects such as two independent photons. In the duality computer, the wave of the duality computer is split into several sub-waves and they pass through different routes, where different computing gate operations are performed. These sub-waves are then re-combined to interfere to give the computational results. The quantum computer, however, has only used the particle nature of quantum object. In a duality computer, it may be possible to find a marked item from an unsorted database using only a single query, and all NP-complete problems may have polynomial algorithms. Two proof-of-the-principle designs of the duality computer are presented: the giant molecule scheme and the nonlinear quantum optics scheme. We also propose thought experiment to check the related fundamental issues, the measurement efficiency of a partial wave function. 展开更多
关键词 quantum interference duality computer NP-complete = P
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Statistical Average of Spin Operators for Calculation of Three-Component Magnetization (II): Solution of Equation 被引量:1
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作者 WANG Huai-Yu LONG Yao CHEN Nan-Xian 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第1期175-179,共5页
In this paper, the solution of Chebyshev equation with its argument being greater than 1 is obtained. The initial value of the derivative of the solution is the expression of magnetization, which is valid for any spin... In this paper, the solution of Chebyshev equation with its argument being greater than 1 is obtained. The initial value of the derivative of the solution is the expression of magnetization, which is valid for any spin quantum number S. The Chebyshev equation is transformed from an ordinary differential equation obtained when we dealt with Heisenberg model, in order to calculate all three components of magnetization, by many-body Green's function under random phase approximation. The Chebyshev functions with argument being greater than 1 are discussed. This paper shows that the Chebyshev polynomials with their argument being greater than 1 have their physical application. 展开更多
关键词 three-component magnetization Heisenberg model many-body Green's function method ordinary differential equation Chebyshev functions
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Computation of the Simplest Normal Forms for Resonant Double Hopf Bifurcations System Based on Lie Transform 被引量:2
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作者 张琪昌 何学军 郝淑英 《Transactions of Tianjin University》 EI CAS 2006年第3期180-185,共6页
The simplest normal form of resonant double Hopf bifurcation was studied based on Lie operator. The coefficients of the simplest normal forms of resonant double Hopf bifurcation and the nonlinear transformations in te... The simplest normal form of resonant double Hopf bifurcation was studied based on Lie operator. The coefficients of the simplest normal forms of resonant double Hopf bifurcation and the nonlinear transformations in terms of the original system coefficients were given explicitly. The nonlinear transformations were used for reducing the lower- and higher-order normal forms, and the rank of system matrix was used to determine the coefficient of normal form which could be reduced. These make the gained normal form simpler than the traditional one. A general program was compiled with Mathematica. This program can compute the simplest normal form of resonant double Hopf bifurcation and the non-resonant form up to the 7th order. 展开更多
关键词 nonlinear systems normal form bifurcation mathematical transformations Lie operator computer program
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Effects of Thermal Lattice Vibration on the Effective Potential of Weak-Coupling Bipolaron in a Quantum Dot 被引量:2
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作者 Eerdunchaolu Wuyunqimuge +2 位作者 XIAO Xin HAN Chao XIN Wei 《Communications in Theoretical Physics》 SCIE CAS CSCD 2012年第1期157-160,共4页
Based on the Huybrechts' linear-combination operator,effects of thermal lattice vibration on the effective potential of weak-coupling bipolaron in semiconductor quantum dots are studied by using the LLP variationa... Based on the Huybrechts' linear-combination operator,effects of thermal lattice vibration on the effective potential of weak-coupling bipolaron in semiconductor quantum dots are studied by using the LLP variational method and quantum statistical theory.The results show that the absolute value of the induced potential of the bipolaron increases with increasing the electron-phonon coupling strength,but decreases with increasing the temperature and the distance of electrons,respectively;the absolute value of the effective potential increases with increasing the radius of the quantum dot,electron-phonon coupling strength and the distance of electrons,respectively,but decreases with increasing the temperature;the temperature and electron-phonon interaction have the important influence on the formation and state properties of the bipolaron:the bipolarons in the bound state are closer and more stable when the electron-phonon coupling strength is larger or the temperature is lower;the confinement potential and coulomb repulsive potential between electrons are unfavorable to the formation of bipolarons in the bound state. 展开更多
关键词 quantum dot BIPOLARON induced potential effective potential thermal lattice vibration polaroneffects
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Quantum Properties of Two-Mode Squeezed Even and Odd Coherent States 被引量:1
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作者 ZHANG Jing WU Wei MENG Shao-Ying 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第2期317-324,共8页
Two new types of quantum states are constructed by applying the operator s(ξ) = exp(ξ* ab - ξa+b+) on the two-mode even and odd coherent states. The mathematical and quantum statistical properties of such st... Two new types of quantum states are constructed by applying the operator s(ξ) = exp(ξ* ab - ξa+b+) on the two-mode even and odd coherent states. The mathematical and quantum statistical properties of such states are investigated. Various nonclassical features of these states, such as squeezing properties, the inter-mode photon bunching, and the violation of Cauchy-Schwarz inequality, are discussed. The Wigner function in these states are studied in detail. 展开更多
关键词 two-mode squeezed even/odd coherent states quantum statistical properties
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The analysis of application of data mining technology in the system of intrusion detection 被引量:2
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作者 Liu Zhijun Pu Xiaowei 《International Journal of Technology Management》 2014年第6期4-5,共2页
With the economic development and the popularity of application of electronic computer, electronic commerce has rapid development. More and more commerce and key business has been carried on the lnternet because Inter... With the economic development and the popularity of application of electronic computer, electronic commerce has rapid development. More and more commerce and key business has been carried on the lnternet because Internet has the features of interaction, openness, sharing and so on. However, during the daily commerce, people worry about the security of the network system. So a new technology which can detect the unusual behavior in time has been invented in order to protect the security of network system. The system of intrusion detection needs a lot of new technology to protect the data of the network system. The application of data mining technology in the system of intrusion detection can provide a better assistant to the users to analyze the data and improve the accuracy of the checking system. 展开更多
关键词 The system of intrusion detection data mining technology APPLICATION
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Parallelization and performance tuning of molecular dynamics code with OpenMP 被引量:3
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作者 白树仁 冉丽萍 鲁奎麟 《Journal of Central South University of Technology》 2006年第3期260-264,共5页
An OpenMP approach was proposed to parallelize the sequential molecular dynamics(MD) code on shared memory machines. When a code is converted from the sequential form to the parallel form, data dependence is a main pr... An OpenMP approach was proposed to parallelize the sequential molecular dynamics(MD) code on shared memory machines. When a code is converted from the sequential form to the parallel form, data dependence is a main problem. A traditional sequential molecular dynamics code is anatomized to find the data dependence segments in it, and the two different methods, i.e., recover method and backward mapping method were used to eliminate those data dependencies in order to realize the parallelization of this sequential MD code. The performance of the parallelized MD code was analyzed by using some performance analysis tools. The results of the test show that the computing size of this code increases sharply form 1 million atoms before parallelization to 20 million atoms after parallelization, and the wall clock during computing is reduced largely. Some hot-spots in this code are found and optimized by improved algorithm. The efficiency of parallel computing is 30% higher than that of before, and the calculation time is saved and larger scale calculation problems are solved. 展开更多
关键词 system analysis molecular dynamics parallel computing performance tuning OPENMP
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Applications of Weyl Ordered Two-Mode Wigner Operator for Quantum MechanicalEntangled System
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作者 FANHong-Yi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第2期205-208,共4页
Based on the technique of integral within a Weyl ordered product of operators, we present applications of the Weyl ordered two-mode Wigner operator for quantum mechanical entangled system, e.g., we derive the complex ... Based on the technique of integral within a Weyl ordered product of operators, we present applications of the Weyl ordered two-mode Wigner operator for quantum mechanical entangled system, e.g., we derive the complex Wigner transform and its relation to the complex fractional Fourier transform, as well as the entangled Radon transform. 展开更多
关键词 Weyl ordering two-mode Wigner operator entangled system
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Modified Projective Synchronization of a New Hyperchaotic System via Nonlinear Control 被引量:1
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作者 LI Xin 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第8期274-278,共5页
In this paper, a nonlinear control scheme of two identical hyperchaotic Chert systems is developed to realize their modified projective synchronization. We achieve modified projective synchronization between the two i... In this paper, a nonlinear control scheme of two identical hyperchaotic Chert systems is developed to realize their modified projective synchronization. We achieve modified projective synchronization between the two identical hyperchaotic systems by directing the scaling factor onto the desired value. With symbolic computation system Maple and Lyapunov stability theory, numerical simulations are given to perform the process of the synchronization. 展开更多
关键词 modified projective synchronization nonlinear control method hyperchaotic Chen system
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Fault diagnosis method for switch control circuit based on SVM-AdaBoost 被引量:5
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作者 WANG Deng-fei CHEN Guang-wu +1 位作者 XING Dong-feng LIANG Dou-dou 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2020年第3期251-257,共7页
In order to realize the fault diagnosis of the control circuit of all-electronic computer interlocking system(ACIS)for railway signals,taking a five-wire switch electronic control module as an research object,we propo... In order to realize the fault diagnosis of the control circuit of all-electronic computer interlocking system(ACIS)for railway signals,taking a five-wire switch electronic control module as an research object,we propose a method of selecting the sample set of the basic classifier by roulette method and realizing fault diagnosis by using SVM-AdaBoost.The experimental results show that the proportion of basic classifier samples affects classification accuracy,which reaches the highest when the proportion is 85%.When selecting the sample set of basic classifier by roulette method,the fault diagnosis accuracy is generally higher than that of the maximum weight priority method.When the optimal proportion 85%is taken,the accuracy is highest up to 96.3%.More importantly,this way can better adapt to the critical data and improve the anti-interference ability of the algorithm,and therefore it provides a basis for fault diagnosis of ACIS. 展开更多
关键词 all-electronic computer interlocking system(ACIS) switch control circuit support vector machine(SVM) ADABOOST fault diagnosis
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