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GPS网平差的多元响应—非线性最小二乘模型及其解的最优化混合算法 被引量:1
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作者 李述山 陶华学 《测绘科学》 CAS CSCD 2004年第1期20-21,共2页
在控制网中,用GPS测量,可以同时测得一个点的基线向量,在具有起算数据时可获得观测点的三维坐标等多个响应变量值,将这些响应变量包含的信息综合起来,可以得到参数的更精确的估计。本文针对GPS测量数据为多元响应数据的特点,建立了一个... 在控制网中,用GPS测量,可以同时测得一个点的基线向量,在具有起算数据时可获得观测点的三维坐标等多个响应变量值,将这些响应变量包含的信息综合起来,可以得到参数的更精确的估计。本文针对GPS测量数据为多元响应数据的特点,建立了一个GPS网平差的多元响应-非线性最小二乘模型,针对该模型,结合拟牛顿法和信赖域算法建立了一个新非线性优化的混合算法,该算法具有全局收敛性和超线性收敛性。 展开更多
关键词 GPS网 多元响应-非线性最小二乘模型 拟牛顿法 信赖域算法 混合算法
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激光诱导击穿光谱技术与偏最小二乘回归法在煤炭灰分检测中的应用 被引量:2
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作者 陆茂荣 《煤质技术》 2020年第2期71-74,共4页
为了解决激光诱导击穿光谱技术(LIBS)的自吸收效应所导致的测量精度降低问题,将LIBS与偏最小二乘回归法(PLS)结合后建立分析模型以有效应用于煤炭灰分的检测。在传统的PLS模型基础上考虑谱线自吸收的影响,根据自吸收后的谱线强度与浓度... 为了解决激光诱导击穿光谱技术(LIBS)的自吸收效应所导致的测量精度降低问题,将LIBS与偏最小二乘回归法(PLS)结合后建立分析模型以有效应用于煤炭灰分的检测。在传统的PLS模型基础上考虑谱线自吸收的影响,根据自吸收后的谱线强度与浓度之间的非线性关系,增加基于谱线强度的平方项并提出谱线自吸收效应的非线性PLS模型。经过自吸收修正后的PLS模型,预测样品的平均误差从1.696%降至1.504%,最大误差从5.780%降至3.507%,模型的预测性能和泛化能力得到了显著提升。 展开更多
关键词 激光诱导击穿光谱技术 最小二乘回归法 灰分 自吸收效应 非线性最小乘模型 谱线强度
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太阳影子定位模型的构建 被引量:7
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作者 胡毅华 杨旭龙 刘媛萍 《洛阳师范学院学报》 2015年第11期13-18,共6页
针对太阳影子定位问题,在合理假设的前提下,建立几何模型,分析影子长度关于各参数的变化规律,求得天安门广场在确定时间的直杆影长变化曲线.根据固定杆的影子顶点坐标确定地点及日期,通过建立非线性最小二乘的最优化模型,以直杆高度的... 针对太阳影子定位问题,在合理假设的前提下,建立几何模型,分析影子长度关于各参数的变化规律,求得天安门广场在确定时间的直杆影长变化曲线.根据固定杆的影子顶点坐标确定地点及日期,通过建立非线性最小二乘的最优化模型,以直杆高度的方差最小为优化目标,以纬度、时角、太阳赤纬角、经度及方位角为分析变量,将地点求解问题转化为直杆高度求解问题,运用遍历法进行求解计算,从而得到较为合理的纬度及相应时间. 展开更多
关键词 非线性最小二乘模型 优化模型 次曲线拟合 遍历法
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基于循环变量筛选非线性偏最小二乘的LIBS铁矿浆定量分析 被引量:16
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作者 尚栋 孙兰香 +2 位作者 齐立峰 谢远明 陈彤 《中国激光》 EI CAS CSCD 北大核心 2021年第21期165-173,共9页
激光诱导击穿光谱(LIBS)技术因其在线、原位、多元素同时测量等优点,在物质成分检测上得到广泛应用。但是,LIBS技术常受到自吸收及基体效应的干扰,分析的准确度较低,同时,随着光谱仪分辨率的不断提高,数据维度越来越高,其中包括大量对... 激光诱导击穿光谱(LIBS)技术因其在线、原位、多元素同时测量等优点,在物质成分检测上得到广泛应用。但是,LIBS技术常受到自吸收及基体效应的干扰,分析的准确度较低,同时,随着光谱仪分辨率的不断提高,数据维度越来越高,其中包括大量对成分分析无用的冗余信息,这就增加了建模的复杂度。为了降低建模的复杂度,减少光谱数据维度以提取最有用的光谱信息,同时减少自吸收及基体效应的非线性干扰对定量分析精度的影响,在传统偏最小二乘(PLS)方法的基础上,提出了利用循环筛选特征变量来校正自吸收及基体效应影响的非线性PLS模型。以铁精矿矿浆样本为分析对象,结果表明,与传统PLS方法相比,所提出的基于循环变量筛选的非线性PLS模型的定量分析精度显著提高,测试样品的均方根误差(RMSE)从1.15%降到0.70%,决定系数R^(2)从0.51提高到0.86。 展开更多
关键词 光谱学 激光诱导击穿光谱 非线性最小乘模型 变量筛选 自吸收效应 基体效应
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Unknown parameter’s variance-covariance propagation and calculation in generalized nonlinear least squares problem 被引量:6
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作者 陶华学 郭金运 《Journal of Coal Science & Engineering(China)》 2005年第1期52-55,共4页
The unknown parameter’s variance-covariance propagation and calculation in the generalized nonlinear least squares remain to be studied now, which didn’t appear in the internal and external referencing documents. Th... The unknown parameter’s variance-covariance propagation and calculation in the generalized nonlinear least squares remain to be studied now, which didn’t appear in the internal and external referencing documents. The unknown parameter’s vari- ance-covariance propagation formula, considering the two-power terms, was concluded used to evaluate the accuracy of unknown parameter estimators in the generalized nonlinear least squares problem. It is a new variance-covariance formula and opens up a new way to evaluate the accuracy when processing data which have the multi-source, multi-dimensional, multi-type, multi-time-state, different accuracy and nonlinearity. 展开更多
关键词 generalized nonlinear least squares problem unknown parameter vari- ance-covariance propagation
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LS-SVM model based nonlinear predictive control for MCFC system
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作者 CHEN Yue-hua CAO Guang-yi ZHU Xin-jian 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第5期748-754,共7页
This paper describes a nonlinear model predictive controller for regulating a molten carbonate fuel cell (MCFC). In order to improve MCFC’s generating performance, prolong its life and guarantee safety, it must be co... This paper describes a nonlinear model predictive controller for regulating a molten carbonate fuel cell (MCFC). In order to improve MCFC’s generating performance, prolong its life and guarantee safety, it must be controlled efficiently. First, the output voltage of an MCFC stack is identified by a least squares support vector machine (LS-SVM) method with radial basis function (RBF) kernel so as to implement nonlinear predictive control. And then, the optimal control sequences are obtained by applying genetic algorithm (GA). The model and controller have been realized in the MATLAB environment. Simulation results indicated that the proposed controller exhibits satisfying control effect. 展开更多
关键词 Molten carbonate fuel cell (MCFC) Least squares support vector machine (LS-SVM) Genetic algorithm (GA) Nonlinear predictive controller
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On minimum cavitation number of the ventilated supercavity in water tunnel 被引量:3
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作者 ZOU Wang YU KaiPing +1 位作者 ARNDTREA KAWAKAMIE 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2013年第10期1945-1951,共7页
A numerical method consisted of the cavitation number correction and the model coefficient correction algorithms is presented to simulate the supercavity in water tunnel considering blockage and gravity effects based ... A numerical method consisted of the cavitation number correction and the model coefficient correction algorithms is presented to simulate the supercavity in water tunnel considering blockage and gravity effects based on the Logvinovich model.A model of the minimum cavitation number is also proposed based on the dimensional analysis theory,and the minimum cavitation number is formulated based on the model and numerical results using the nonlinear least square method(NLLS).The formula is verified by experiment to some extent. 展开更多
关键词 supercavity minimum cavitation number Froude number blockage ratio NLLS
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Nonlinear multifunctional sensor signal reconstruction based on least squares support vector machines and total least squares algorithm 被引量:2
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作者 Xin LIU Guo WEI +1 位作者 Jin-wei SUN Dan LIU 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2009年第4期497-503,共7页
Least squares support vector machines (LS-SVMs) are modified support vector machines (SVMs) that involve equality constraints and work with a least squares cost function, which simplifies the optimization procedure. I... Least squares support vector machines (LS-SVMs) are modified support vector machines (SVMs) that involve equality constraints and work with a least squares cost function, which simplifies the optimization procedure. In this paper, a novel training algorithm based on total least squares (TLS) for an LS-SVM is presented and applied to multifunctional sensor signal reconstruction. For three different nonlinearities of a multifunctional sensor model, the reconstruction accuracies of input signals are 0.001 36%, 0.031 84% and 0.504 80%, respectively. The experimental results demonstrate the higher reliability and accuracy of the proposed method for multifunctional sensor signal reconstruction than the original LS-SVM training algorithm, and verify the feasibility and stability of the proposed method. 展开更多
关键词 Least squares support vector machine Total least squares Multifunctional sensor Signal reconstruction
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