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A Study Regarding Solution of a Knowledge Model Based on the Containing-Type Error Matrix Equation 被引量:1
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作者 Xilin Min Kaizhong Guo Jize Huang 《Engineering(科研)》 2012年第8期484-492,共9页
An error matrix equation based on error matrix theory was presented in previous research of the error-eliminating theory. The purpose of solving the error matrix equation is to create a decision support on how to swit... An error matrix equation based on error matrix theory was presented in previous research of the error-eliminating theory. The purpose of solving the error matrix equation is to create a decision support on how to switch from bad to good status. A matrix based on error logic is used to express current status u, expectant status u1 and transformation matrix T. It is u, u1, and T that are used to build error matrix equation T (u)= u1. This allows us to find a method whereby bad status “u” changes to good status “u1” by solving the equation. The conversion method that transform from current to expectant status can be obtained from the transformation matrix T. On this basis, this paper proposes a new kind of error matrix equation named “containing-type error matrix equation”. This equation is more suitable for analyzing the realistic question. The method of solving, existence and form of solution for this type of equation have been presented in this paper. This research provides a potential useful new technique for decision analysis. 展开更多
关键词 error matrix SET EQUATION Containing-Type error matrix EQUATION KNOWLEDGE Model
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Real-Time Error Analysis of Multi-Channel Capacitive Voltage Transformer Using Co-Prediction Matrix
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作者 Jiusong Hu Ao Xiong +2 位作者 Yongqi Liu Guaxuan Xiao Yi Zhong 《Journal of Power and Energy Engineering》 2025年第1期1-17,共17页
Capacitive voltage transformers (CVTs) are essential in high-voltage systems. An accurate error assessment is crucial for precise energy metering. However, tracking real-time quantitative changes in capacitive voltage... Capacitive voltage transformers (CVTs) are essential in high-voltage systems. An accurate error assessment is crucial for precise energy metering. However, tracking real-time quantitative changes in capacitive voltage transformer errors, particularly minor variations in multi-channel setups, remains challenging. This paper proposes a method for online error tracking of multi-channel capacitive voltage transformers using a Co-Prediction Matrix. The approach leverages the strong correlation between in-phase channels, particularly the invariance of the signal proportions among them. By establishing a co-prediction matrix based on these proportional relationships, The influence of voltage changes on the primary measurements is mitigated. Analyzing the relationships between the co-prediction matrices over time allows for inferring true measurement errors. Experimental validation with real-world data confirms the effectiveness of the method, demonstrating its capability to continuously track capacitive voltage transformer measurement errors online with precision over extended durations. 展开更多
关键词 Capacitive Voltage Transformers Co-Prediction matrix HIGH-VOLTAGE Measurement error
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ADAPTIVE FLOW SOLUTION BASED ON MATRIX ERROR
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作者 欧阳绍修 刘学强 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2010年第3期199-204,共6页
An adaptive method for the solution of compressible flows is described. The idea results from the desire for an efficient grid system,and an accurate and robust solution method are used to resolve flow features of the... An adaptive method for the solution of compressible flows is described. The idea results from the desire for an efficient grid system,and an accurate and robust solution method are used to resolve flow features of the interest. The adaptation flow solution is proposed,including the detection of flow features based on the matrix error; the mesh adaptation using the mesh movement,the mesh refinement,the mesh coarsening,and their combination. The feature detection based on the matrix error can maintain the high resolution property for shock waves of the one-dimensional approximate Riemann solver and the higher order reconstruction scheme. The high grid efficiency is obtained with the anisotropically directional grid corresponding to feature directions,and the error of the flow-field is averaged. The procedure and its application to flow solutions of shock waves are described. Results validate that the method is reliable. 展开更多
关键词 grid computing adaptive algorithm matrix errors fluid dynamics
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MATRIX ALGORITHMS AND ERROR FORMULA FOR BIVARIATE THIELE-TYPE RECTANGULAR MATRIX VALUED RATIONAL INTERPOLATION 被引量:1
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作者 顾传青 朱功勤 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 1999年第2期195-208,共14页
A new method for the construction of bivariate matrix valued rational interpolants (BGIRI) on a rectangular grid is presented in [6]. The rational interpolants are of Thiele-type continued fraction form with scalar de... A new method for the construction of bivariate matrix valued rational interpolants (BGIRI) on a rectangular grid is presented in [6]. The rational interpolants are of Thiele-type continued fraction form with scalar denominator. The generalized inverse introduced by [3]is gen-eralized to rectangular matrix case in this paper. An exact error formula for interpolation is ob-tained, which is an extension in matrix form of bivariate scalar and vector valued rational interpola-tion discussed by Siemaszko[l2] and by Gu Chuangqing [7] respectively. By defining row and col-umn-transformation in the sense of the partial inverted differences for matrices, two type matrix algorithms are established to construct corresponding two different BGIRI, which hold for the vec-tor case and the scalar case. 展开更多
关键词 BIVARIATE matrix VALUED RATIONAL inter polants error FORMULA matrix algorithms.
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顾及星敏感器安装矩阵校正的GRACE-FO姿态数据处理研究
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作者 梁磊 王长青 +5 位作者 黄令勇 黄志勇 于瑶瑶 钟敏 闫易浩 穆庆禄 《测绘学报》 北大核心 2026年第2期287-300,共14页
如何获取高精度的姿态数据是重力卫星载荷数据处理的重要研究内容。GRACE-FO的每颗卫星均搭载了3颗星敏感器和1个陀螺仪,融合这两类载荷的测量数据是获得高精度姿态数据的重要途径。本文首先根据星敏感器测量噪声具有各向异性的特点,建... 如何获取高精度的姿态数据是重力卫星载荷数据处理的重要研究内容。GRACE-FO的每颗卫星均搭载了3颗星敏感器和1个陀螺仪,融合这两类载荷的测量数据是获得高精度姿态数据的重要途径。本文首先根据星敏感器测量噪声具有各向异性的特点,建立了星敏感器安装矩阵标定算法;其次,建立了星敏感器低频误差处理方法,使用滑动平均方法抑制低频误差;然后,基于Gibbs矢量建立了四元数改正量和陀螺仪偏差改正量为状态向量的间接Kalman滤波算法;最后,使用GRACE-FO Level-1A数据进行验证,并分析其对时变重力场的影响。结果表明,以其中1个星敏感器为基准,校正另外两颗星敏感器安装矩阵时,解算的卫星姿态差异较小,经过星敏感器安装矩阵校正后,可以降低姿态数据在1个轨道周期(CPR)处的低频误差。根据建立的星敏感器低频误差处理策略,可以较好地压制30 CPR频段内的星敏感器低频误差。对于星敏感器和陀螺仪融合,相较于JPL结果,本文解算的姿态数据为0.0005~0.1 Hz,具有更低的噪声,充分发挥了载荷最大性能。对时变重力场模型反演的影响,从反演的时变重力场的阶方差和等效水高差异上看,基于不同姿态数据解算的时变重力场模型精度基本一致,目前姿态数据精度的提升对时变重力场模型精度影响较小。 展开更多
关键词 GRACE-FO 卫星姿态 星敏感器低频误差 安装矩阵校正 间接Kalman滤波
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机翼气动弹性缩比模型刚度测量设备的误差建模与分析
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作者 郑科 韦磊 +1 位作者 包海涛 杨睿 《组合机床与自动化加工技术》 北大核心 2026年第2期12-16,共5页
机翼气动弹性缩比模型刚度测量设备用于测量机翼气动弹性缩比模型的刚度分布矩阵,从而验证其设计制造是否达标。该设备主要由机床机械结构和高精度传感器等组成,具有结构复杂、误差来源多样等特点。传统简单几何测量设备的误差分析方法... 机翼气动弹性缩比模型刚度测量设备用于测量机翼气动弹性缩比模型的刚度分布矩阵,从而验证其设计制造是否达标。该设备主要由机床机械结构和高精度传感器等组成,具有结构复杂、误差来源多样等特点。传统简单几何测量设备的误差分析方法针对现阶段的设备不适用。通过分析机翼弹性缩比模型刚度测量设备的测量原理与组成,提出一种以齐次误差传递模型为基础,同时引入传感器误差、刚度分布矩阵优劣因子的误差传递模型。通过定义非对称度函数,将多种误差因子统一量化,进而计算各误差因子的灵敏度。通过激光跟踪仪等高精度测量手段,确定各误差因子的实际误差值,并计算实际非对称度,将实际非对称度与理论非对称度进行实验对比分析,结果表明,理论误差传递模型的预测结果与实际测量结果的误差不超过5%,验证了模型的准确性。 展开更多
关键词 误差建模 非对称度 刚度分布矩阵 机翼刚度测量设备
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基于DSP的双倍双精度矩阵求逆技术
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作者 辛珍妮 陈颖 席国江 《电讯技术》 北大核心 2026年第2期320-326,共7页
矩阵求逆运算作为信号处理的基础运算在数字信号处理、无线通信技术等领域中得到广泛应用。然而在处理较高条件数的矩阵求逆运算时,浮点计算舍入误差的累积效应会被显著放大,传统的矩阵求逆方法难以获得可信的数值结果。为解决该问题,... 矩阵求逆运算作为信号处理的基础运算在数字信号处理、无线通信技术等领域中得到广泛应用。然而在处理较高条件数的矩阵求逆运算时,浮点计算舍入误差的累积效应会被显著放大,传统的矩阵求逆方法难以获得可信的数值结果。为解决该问题,利用无误差变换技术,在工作精度(双精度)下,实现了双倍双精度浮点运算,并基于数字信号处理器开发了双倍双精度基本运算函数库。在此基础上,设计并实现了基于QR分解的双倍双精度矩阵求逆技术。通过大量不同类型矩阵的数值实验,表明所提算法显著降低了矩阵求逆计算的误差,对条件数较大的矩阵仍能实现可靠的矩阵求逆计算。 展开更多
关键词 矩阵求逆 无误差变换 双倍双精度算法 舍入误差
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Mean Square Error Comparisons of Estimatorsin Two SUR Models
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作者 LIU Jin-shan GUI Qing-ming 《Chinese Quarterly Journal of Mathematics》 CSCD 2000年第3期63-71,共9页
For a system of two seerningly umrelated regressions.some general results of mean square er-ror matrix comparisons are presented.A class of linear estimators and a class of two-stage estimatorsbased on a generalized u... For a system of two seerningly umrelated regressions.some general results of mean square er-ror matrix comparisons are presented.A class of linear estimators and a class of two-stage estimatorsbased on a generalized unrestricted estimate of the dispersion matrix are proposed.Some exact finitesample properties of the two-stage estimators are obtained. 展开更多
关键词 seemingly unrelated regressions two-stage estimator mean square error matrix
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基于Reed-Solomon码的Data Matrix条码纠错研究 被引量:2
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作者 赖忠喜 占红武 《机电工程》 CAS 2009年第8期62-65,共4页
为了研究Data Matrix条码的纠错能力,首先介绍了Data Matrix条码的特点和Reed-Solomon码的基本概念;接着研究了Reed-Solomon码在Data Matrix二维条码中的应用,重点分析了Data Matrix二维条码中Reed-Solomon编、解码的基本原理与步骤,并... 为了研究Data Matrix条码的纠错能力,首先介绍了Data Matrix条码的特点和Reed-Solomon码的基本概念;接着研究了Reed-Solomon码在Data Matrix二维条码中的应用,重点分析了Data Matrix二维条码中Reed-Solomon编、解码的基本原理与步骤,并用C语言实现它的编、解码算法;最后对Reed-Solomon码的纠错能力进行了测试。实验结果表明,Data Matrix二维条码采用Reed-Solomon码作为纠错码,可以有效地排除干扰并进行纠错。 展开更多
关键词 数据矩阵 Reed—Solomon码 纠错码 Euclid算法
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基于Reed-Solomon算法的DataMatrix条码纠错码的研究 被引量:5
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作者 陈刚 王典洪 《现代电子技术》 2006年第5期57-58,61,共3页
DataMatrix是一种矩阵二维条码,具有信息密度大、容量高、面积小等优点,同时,其译码时受噪声干扰也较大,因此,DataMatrix二维条码采用了ReedSolomon算法作为纠错码,可以有效地排除干扰进行纠错。首先介绍DataMatrix条码的特点,然后详细... DataMatrix是一种矩阵二维条码,具有信息密度大、容量高、面积小等优点,同时,其译码时受噪声干扰也较大,因此,DataMatrix二维条码采用了ReedSolomon算法作为纠错码,可以有效地排除干扰进行纠错。首先介绍DataMatrix条码的特点,然后详细介绍了ReedSolomon算法的原理和伽罗华域的基本运算规则和构造规则,重点分析研究他在DataMatrix二维条码中的应用,构造了他的实现算法和其纠错编码的实现电路并通过实例进行了具体的说明,同时讨论了RS的译码步骤。 展开更多
关键词 DATA matrix 伽罗毕域 Reed-Solomon算法 纠错码
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防错设计在活塞点阵标识生产中的应用
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作者 王涛 黄永松 +1 位作者 宋加兵 程功 《科技创新与生产力》 2026年第1期121-122,125,共3页
防错设计是实现零缺陷的有效手段。文章介绍活塞点阵标识生产中的防错设计,基于防错设计的基本原理,进行产品自身结构防错设计和点阵标识防错装置的设计。应用于实际生产,提高了产品合格率,取得良好的效果。
关键词 零缺陷 防错设计 防错装置 点阵标识
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双摇篮五轴机床位置无关几何误差辨识
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作者 赵烨炜 孙豪 +2 位作者 陈绪兵 付中涛 朱泽润 《武汉工程大学学报》 2026年第1期95-102,共8页
装配误差是位置无关几何误差的主要来源,是影响五轴数控机床加工精度的重要因素,而最小完备误差项分析和位置无关几何误差精确辨识仍然面临巨大挑战。针对以上问题,本文提出一种位置无关几何误差辨识模型,该模型基于齐次坐标变换矩阵,... 装配误差是位置无关几何误差的主要来源,是影响五轴数控机床加工精度的重要因素,而最小完备误差项分析和位置无关几何误差精确辨识仍然面临巨大挑战。针对以上问题,本文提出一种位置无关几何误差辨识模型,该模型基于齐次坐标变换矩阵,结合微分运动学原理,建立了机床各部件的局部装配误差与末端轮廓误差之间的映射模型;进一步根据相邻坐标系位置全局误差与局部误差的映射关系,构建全局坐标系和局部坐标系的误差映射模型。针对冗余误差项影响的误差辨识精度问题,提出全局误差映射雅可比矩阵分析的方法,将42项局部误差参数优化转换为17项最小完备全局误差参数,确保误差辨识的完整性与非冗余性,相关结果与ISO 230-1:2012标准分析获得的位置无关几何误差项保持一致。在仿真验证方面,构建虚拟五轴机床模型,采用球杆仪仿真测试方案,设置测量系统误差为0.1μm,对机床各部件装配误差进行辨识;验证结果显示,位置误差辨识精确度达0.992 9,姿态误差辨识精确度达0.954 9,证实了模型的有效性,为机床精度提升与误差补偿提供了科学依据。 展开更多
关键词 位置无关几何误差 轮廓误差 参数辨识 微分运动学 五轴数控机床 雅可比矩阵
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On the Matrix and Additive Communication Channels
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作者 Vladimir Leontiev Garib Movsisyan +1 位作者 Arthur Osipyan Zhirayr Margaryan 《Journal of Information Security》 2014年第4期178-191,共14页
The notion of a communication channel is one of the key notions in information theory but like the notion “information” it has not any general mathematical definition. The existing examples of the communication chan... The notion of a communication channel is one of the key notions in information theory but like the notion “information” it has not any general mathematical definition. The existing examples of the communication channels: the Gaussian ones;the binary symmetric ones;the ones with symbol drop-out and drop-in;the ones with error packets etc., characterize the distortions which take place in information conducted through the corresponding channel. 展开更多
关键词 ADDITIVE Communication CHANNEL error matrix CHANNEL NEIGHBORHOOD CORRECTING Code ALPHABET
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Error Analysis of Assembly Linkage of Transport Jig for Large Aircraft Parts
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作者 倪雁冰 潘琪 +1 位作者 郭雯侠 白永超 《Transactions of Tianjin University》 EI CAS 2013年第6期440-447,共8页
Aiming at the assembly accuracy of a large aircraft transport jig, the effect of component error and the error of work-piece surface on the work-piece position and orientation in the 3-2-1 fixturing scheme is studied ... Aiming at the assembly accuracy of a large aircraft transport jig, the effect of component error and the error of work-piece surface on the work-piece position and orientation in the 3-2-1 fixturing scheme is studied with the object pose space description method. The error mapping model between the connecting part of the front frame rack and its support base is modeled using the homogeneous transformation matrix(HTM) method. The probabilistic error is simulated using the Monte Carlo method. The measurement experiment was conducted by the laser tracker to verify the effectiveness of the approach, and the approach has been successfully applied to the production of transport jig. 展开更多
关键词 assembly linkage error modeling homogeneous transformation matrix Monte Carlo method
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A New Algorithm of Roundness Error Separation Technique of Three-point Method
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作者 雷贤卿 李济顺 +3 位作者 薛玉君 马伟 崔凤奎 胡东方 《Defence Technology(防务技术)》 SCIE EI CAS 2008年第2期141-145,共5页
Through the analysis of roundness error separation technique of three-point method and based on the invariability and periodicity of the geometrical characteristic of measured round contour, a new matrix algorithm, wh... Through the analysis of roundness error separation technique of three-point method and based on the invariability and periodicity of the geometrical characteristic of measured round contour, a new matrix algorithm, which can be used to solve directly the roundness of the measured round contour without Fourier transform, is presented. On the basis of the research and analysis of the rotation error movement which is separated by using the three-point method, a mathematical equation is derived, which can be used to separate the eccentric motion of least square center of measured round contour and the pure rotation motion error of spindle in rotation motion. The correctness of this method is validated by means of simulation. 展开更多
关键词 信息加工 三点方法 矩阵 偏心运动
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ACCURATE COMPUTATION FOR IRREDUCIBLE NONSINGULAR M-MATRIX
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作者 薛军工 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 1995年第1期116-117,共2页
Computing the eigenvalue of smallest modulus and its corresponding eigneveclor of an irreducible nonsingular M-matrix A is considered, It is shown that if the entries of A are known with high relative accuracy, its ei... Computing the eigenvalue of smallest modulus and its corresponding eigneveclor of an irreducible nonsingular M-matrix A is considered, It is shown that if the entries of A are known with high relative accuracy, its eigenvalue of smallest modulus and each component of the corresponding eigenvector will be determined to much higher accuracy than the standard perturbation theory suggests. An algorithm is presented to compute them with a small componentwise backward error, which is consistent with the perturbation results. 展开更多
关键词 IRREDUCIBLE NONSINGULAR M-matrix BACKWARD error componentwise PERTURBATION
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ERROR ANALYSIS FOR SOLVING VANDERMONDE SYSTEM WITH SPECIAL POINTS
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作者 曲延云 蒋尔雄 薛军工 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2003年第1期111-120,共10页
The Bjorck and Pereyra algorithms used for solving Vandermonde systemof equation are modified for the case where the points are symmetricly situated aroundzero. The working operation is saved about half. A forward err... The Bjorck and Pereyra algorithms used for solving Vandermonde systemof equation are modified for the case where the points are symmetricly situated aroundzero. The working operation is saved about half. A forward error analysis is presentedfor the modified algorithms, and it's shown that if the points are situated in some order,the error bound are as good as Higham's result in 1987. 展开更多
关键词 线性控制系统 Vandermonde系统 VANDERMONDE矩阵 零点 误差分析
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Reduction of Systematic Error in Radiopharmaceutical Activity by Entropy Based Mutual Information
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作者 Palliyakarany T. K. Kumar Toshikazu Takeda 《World Journal of Nuclear Science and Technology》 2012年第1期1-5,共5页
The quality of the radiation dose depends upon the gamma count rate of the radionuclide used. Any reduction in error in the count rate is reflected in the reduction in error in the activity and consequently on the qua... The quality of the radiation dose depends upon the gamma count rate of the radionuclide used. Any reduction in error in the count rate is reflected in the reduction in error in the activity and consequently on the quality of dose. All the efforts so far have been directed only to minimize the random errors in count rate by repetition. In the absence of probability distribution for the systematic errors, we propose to minimize these errors by estimating the upper and lower limits by the technique of determinant in equalities developed by us. Using the algorithm we have developed based on the tech- nique of determinant inequalities and the concept of maximization of mutual information (MI), we show how to process element by element of the covariance matrix to minimize the correlated systematic errors in the count rate of 113 mIn. The element wise processing of covariance matrix is so unique by our technique that it gives experimentalists enough maneuverability to mitigate different factors causing systematic errors in the count rate and consequently the activity of 113 mIn. 展开更多
关键词 Random and Systematic errorS Covariance matrix Limits for Correlated Elements by DETERMINANT INEQUALITIES Mutual INFORMATION REDUCTION of Systematic errorS by Maximizing Mutual INFORMATION
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鞍形索网结构索夹安装位置误差影响分析 被引量:1
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作者 吴金志 邵玉荣 +1 位作者 薛宇 孙国军 《北京工业大学学报》 北大核心 2025年第10期1203-1210,共8页
在索网施工过程中,制作和安装误差会对结构的成形态产生影响。现有研究大多聚焦于索长误差、拉索刚度误差以及支座安装误差的影响,较少关注索夹安装位置误差影响。为了探究索夹安装位置误差对鞍形索网结构受力性能的影响,首先推导了索... 在索网施工过程中,制作和安装误差会对结构的成形态产生影响。现有研究大多聚焦于索长误差、拉索刚度误差以及支座安装误差的影响,较少关注索夹安装位置误差影响。为了探究索夹安装位置误差对鞍形索网结构受力性能的影响,首先推导了索力偏差与索夹安装位置误差的敏感度矩阵,基于敏感度矩阵分析给出最大索力偏差和索夹位置误差的最不利分布求解方法;随后,研究了不同矢跨比、网格尺寸和预应力对最大索力偏差的影响;最后,将提出的方法应用于2个鞍形索网结构工程的索夹安装位置误差影响分析。研究发现,鞍形索网结构的索夹最不利安装位置误差主要分布在靠近支座的索段;随着矢跨比增大、网格尺寸减小,索夹位置误差导致的最大索力偏差亦增大;矢跨比越大,网格尺寸的影响越显著;当网格尺寸达到4 m时,不同矢跨比索网的最大索力偏差均在1%左右;预应力对最大索力偏差影响较小;对于百米级的索网结构,由索夹位置误差引起的最大索力偏差能达到3.6%。 展开更多
关键词 鞍形索网 索夹误差 索力偏差 最不利误差分布 敏感度矩阵 影响因素分析
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基于超参数优化和误差修正的STAGN超短期风电功率预测 被引量:3
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作者 潘超 王超 +1 位作者 孙惠 孟涛 《电力系统保护与控制》 北大核心 2025年第8期117-129,共13页
针对风电功率预测模型的数据关联性与误差修正适应性问题,提出基于超参数优化和误差修正单元切换的超短期风电功率预测方法。首先,构建时空注意力门控网络预测模型,利用改进开普勒算法进行超参数优化。然后,考虑风电场数据与预测误差之... 针对风电功率预测模型的数据关联性与误差修正适应性问题,提出基于超参数优化和误差修正单元切换的超短期风电功率预测方法。首先,构建时空注意力门控网络预测模型,利用改进开普勒算法进行超参数优化。然后,考虑风电场数据与预测误差之间的非线性关联,构建误差修正自适应单元。同时挖掘风速时序变化特征,构建深度学习单元。在此基础上,提出基于风速矩阵梯度的误差修正单元切换策略。最后,将模型应用于实际风场的功率预测并与其他模型对比分析。结果表明,所提方法在预测精度上优于其他方法,且在风速复杂多变的风场仍具有较高预测精度,验证了所提方法的准确性和适用性。 展开更多
关键词 超短期风电功率预测 改进开普勒算法 误差修正 风速矩阵梯度
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