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Rapid determination of thiabendazole in orange extract using excitation-emission matrix fluorescence and second-order calibration based on alternating trilinear decomposition/alternating normalization-weighted error algorithms 被引量:2
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作者 WANG XueMei WU HaiLong +3 位作者 NIE JinFang LI YuanNa YU YongJie YU RuQin 《Science China Chemistry》 SCIE EI CAS 2008年第8期729-735,共7页
A novel approach is proposed for direct quantitative analysis of thiabendazole in the orange extract by using excitation-emission matrix fluorescence coupled with second-order calibration methods based on the alternat... A novel approach is proposed for direct quantitative analysis of thiabendazole in the orange extract by using excitation-emission matrix fluorescence coupled with second-order calibration methods based on the alternating trilinear decomposition(ATLD) and the alternating normalization-weighted error(ANWE) algorithms,respectively. The average recoveries of thiabendazole in the orange extract by using ATLD and ANWE with an estimated component number of two were 99.7 ± 3.3% and 103.5 ± 4.1%,respectively. Furthermore,the accuracy of the two algorithms was also evaluated through elliptical joint confidence region(EJCR) tests as well as figures of merit,such as sensitivity(SEN),selectivity(SEL) and limit of detection(LOD). The experimental results demonstrate that both algorithms have been satisfactorily applied to the determination of thiabendazole in orange extract,and the perform-ance of ANWE is slightly better than that of ATLD. 展开更多
关键词 excitation-emission matrix fluorescence alternating trilinear decomposition alternating normalization-weighted error ORANGE EXTRACT THIABENDAZOLE
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ON THE ERROR-SUM FUNCTION OF ALTERNATING LüROTH SERIES
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作者 Luming Shen Chao Ma Jihong Zhang 《Analysis in Theory and Applications》 2006年第3期223-232,共10页
The error-sum function of alternating Lǖroth series is introduced, which, to some extent, discerns the superior or not of an expansion comparing to other expansions. Some elementary properties of this function are st... The error-sum function of alternating Lǖroth series is introduced, which, to some extent, discerns the superior or not of an expansion comparing to other expansions. Some elementary properties of this function are studied. Also, the Hausdorff dimension of graph of such function is determined. 展开更多
关键词 alternating Lǖroth series error-sum function Hausdorff dimension
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Some Properties on the Error-Sum Function of Alternating Sylvester Series
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作者 Huiping Jing Luming Shen 《Advances in Pure Mathematics》 2012年第6期459-463,共5页
The error-sum function of alternating Sylvester series is introduced. Some elementary properties of this function are studied. Also, the hausdorff dimension of the graph of such function is determined.
关键词 alternating SYLVESTER SERIES error-Sum Function HAUSDORFF Dimension
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Alternating Direction Finite Volume Element Methods for Three-Dimensional Parabolic Equations 被引量:1
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作者 Tongke Wang 《Numerical Mathematics(Theory,Methods and Applications)》 SCIE 2010年第4期499-522,共24页
This paper presents alternating direction finite volume element methods for three-dimensional parabolic partial differential equations and gives four computational schemes, one is analogous to Douglas finite differenc... This paper presents alternating direction finite volume element methods for three-dimensional parabolic partial differential equations and gives four computational schemes, one is analogous to Douglas finite difference scheme with second-order splitting error, the other two schemes have third-order splitting error, and the last one is an extended LOD scheme. The L2 norm and H1 semi-norm error estimates are obtained for the first scheme and second one, respectively. Finally, two numerical examples are provided to illustrate the efficiency and accuracy of the methods. 展开更多
关键词 Three-dimensional parabolic equation alternating direction method finite volume element method error estimate
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NEW ALTERNATING DIRECTION FINITE ELEMENT SCHEME FOR NONLINEAR PARABOLIC EQUATION
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作者 Cui Xia(崔霞) 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2002年第1期76-88,共13页
A new alternating direction (AD) finite element (FE) scheme for 3-dimensional nonlinear parabolic equation and parabolic integro-differential equation is studied. By using AD,the 3-dimensional problem is reduced to a ... A new alternating direction (AD) finite element (FE) scheme for 3-dimensional nonlinear parabolic equation and parabolic integro-differential equation is studied. By using AD,the 3-dimensional problem is reduced to a family of single space variable problems, calculation work is simplified; by using FE, high accuracy is kept; by using various techniques for priori estimate for differential equations such as inductive hypothesis reasoning, the difficulty arising from the nonlinearity is treated. For both FE and ADFE schemes, the convergence properties are rigorously demonstrated, the optimal H1- and L2-norm space estimates and the O((△t)2) estimate for time variable are obtained. 展开更多
关键词 nonlinear PARABOLIC equation alternating direction FINITE ELEMENT method error estimate.
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A Local Discontinuous Galerkin Method with Generalized Alternating Fluxes for 2D Nonlinear Schrödinger Equations
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作者 Hongjuan Zhang Boying Wu Xiong Meng 《Communications on Applied Mathematics and Computation》 2022年第1期84-107,共24页
In this paper,we consider the local discontinuous Galerkin method with generalized alter-nating numerical fluxes for two-dimensional nonlinear Schrödinger equations on Carte-sian meshes.The generalized fluxes not... In this paper,we consider the local discontinuous Galerkin method with generalized alter-nating numerical fluxes for two-dimensional nonlinear Schrödinger equations on Carte-sian meshes.The generalized fluxes not only lead to a smaller magnitude of the errors,but can guarantee an energy conservative property that is useful for long time simulations in resolving waves.By virtue of generalized skew-symmetry property of the discontinuous Galerkin spatial operators,two energy equations are established and stability results con-taining energy conservation of the prime variable as well as auxiliary variables are shown.To derive optimal error estimates for nonlinear Schrödinger equations,an additional energy equation is constructed and two a priori error assumptions are used.This,together with properties of some generalized Gauss-Radau projections and a suitable numerical initial condition,implies optimal order of k+1.Numerical experiments are given to demonstrate the theoretical results. 展开更多
关键词 Local discontinuous Galerkin method Two-dimensional nonlinear Schrödinger equation Generalized alternating fluxes Optimal error estimates
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Discussion about the Side Effect of Error Corrective Feedback and Possible Alternatives to Error Correction
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作者 高颐心 《海外英语》 2018年第20期248-249,共2页
Feedbacks given by teachers is possibly a common instruction in second language writing classes, to help students makeprogress in writing. At one time, feedback was almost entirely at a superficial level--identifying ... Feedbacks given by teachers is possibly a common instruction in second language writing classes, to help students makeprogress in writing. At one time, feedback was almost entirely at a superficial level--identifying the grammatical errors and givingthe correct form. However, recently, this type of feedback has begun to be challenged by some researchers(eg.,Krashen, 1984, Trus-cott, 1996),who argue that teachers should be more concerned with the content of essay instead of grammatical errors. This essaywill discuss some research surrounding feedback to students' writing and will try to find the answer to the question whether the er-ror corrective feedback should be abandoned. In order to find the answer, the essay will elaborate on two parts: some literary reviewabout the issue and some suggested solutions to the issue. 展开更多
关键词 error corrective feedback alternative approaches
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THE CHARACTERISTIC FINITE ELEMENT ALTERNATING-DIRECTION METHOD AND ANALYSIS FOR THREE-DIMENSIONAL NUMERICAL RESERVOIR SIMULATION
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作者 袁益让 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 1999年第1期21-34,共14页
Petroleum science has made remarkable progress in organic geochcmistry and in the research into the theories of petroleum origin, its transport and accumulation. In estimating the oil-gas resources of a basin, the kno... Petroleum science has made remarkable progress in organic geochcmistry and in the research into the theories of petroleum origin, its transport and accumulation. In estimating the oil-gas resources of a basin, the knowledge of its evolutionary history and especially the numerical computation of fluid flow and the history of its changes under heat is vital. The mathematical model can be described as a coupled system of nonlinear partial differentical equations with initial-boundary value problems. This thesis, from actual conditions such as the effect of fluid compressibility and the three-dimensional characteristic of large-scale science-engineering computation, we put forward a kind of characteristic finite element alternating-direction schemes and obtain optimal order estimates in L^2 norm for the error in the approximate assumption. 展开更多
关键词 THREE-DIMENSIONAL problem COMPRESSIBILITY alternating-direction characteritic FINITE element optimal order error ESTIMATES in L^2.
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ALTERNATING DIRECTIONFINITE ELEMENT METHOD FORSOME REACTION DIFFUSION MODELS
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作者 江成顺 刘蕴贤 沈永明 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2004年第2期172-182,共11页
This paper is concerned with some nonlinear reaction - diffusion models. To solve this kind of models, the modified Laplace finite element scheme and the alternating direction finite element scheme are established for... This paper is concerned with some nonlinear reaction - diffusion models. To solve this kind of models, the modified Laplace finite element scheme and the alternating direction finite element scheme are established for the system of patrical differential equations. Besides, the finite difference method is utilized for the ordinary differential equation in the models. Moreover, by the theory and technique of prior estimates for the differential equations, the convergence analyses and the optimal L2- norm error estimates are demonstrated. 展开更多
关键词 非线性反应扩散模型 Laplace有限元方法 有限差分法 L^2-标准误差估计
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求Alternant码最小距离下界
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作者 岳殿武 《大连理工大学学报》 EI CAS CSCD 北大核心 1991年第4期385-388,418,共5页
陈克非给出了Alternant码最小距离新下界,但要具体求出这个下界,需要进行有限域上求解共扼元集合的复杂运算。为了避免这个复杂运算过程,给出了循环陪集一个特性,并利用这一特性导出了这个下界新的表示定理,运用表示定理... 陈克非给出了Alternant码最小距离新下界,但要具体求出这个下界,需要进行有限域上求解共扼元集合的复杂运算。为了避免这个复杂运算过程,给出了循环陪集一个特性,并利用这一特性导出了这个下界新的表示定理,运用表示定理求解下界运算得到了很大简化。文中还给出了一定情况下求下界的统一公式。 展开更多
关键词 信息论 alternant码 最小距离
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Chebyshev Fitting Way and Error Analysis for Propeller Atlas across Four Quadrants 被引量:20
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作者 LI Dian-pu, WANG Zong-yi, CHI Hai-hong College of Automation , Harbin Engineering University, Harbin 150001, China 《Journal of Marine Science and Application》 2002年第1期52-59,共8页
A Chebyshev fitting way for a propeller atlas across four quadrants is discussed. As an example, Chebyshev polynomial fitting results and its error analysis are given. Because it’s difficult generally to get a propel... A Chebyshev fitting way for a propeller atlas across four quadrants is discussed. As an example, Chebyshev polynomial fitting results and its error analysis are given. Because it’s difficult generally to get a propeller atlas across four quadrants, a way is used to construct an alternative with higher accuracy based on the properties. As an application example, an alternative for the propeller property of a Deep Submergence Vehicle across four quadrants is given practically and a simulation model of the four quadrants propeller for dynamic condition is set up. The model lays a foundation for DSV full operating-condition movement simulation. A lot of simulation work shows that the results are very close to the practical data and, therefore, are effective. 展开更多
关键词 PROPELLER four quadrants property dynamic simulation ATLAS Chebyshev polynomial DSV alternative property error analysis
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Lowering the Error Floor of ADMM Penalized Decoder for LDPC Codes 被引量:1
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作者 Jiao Xiaopeng Mu Jianjun 《China Communications》 SCIE CSCD 2016年第8期127-135,共9页
Decoding by alternating direction method of multipliers(ADMM) is a promising linear programming decoder for low-density parity-check(LDPC) codes. In this paper, we propose a two-step scheme to lower the error floor of... Decoding by alternating direction method of multipliers(ADMM) is a promising linear programming decoder for low-density parity-check(LDPC) codes. In this paper, we propose a two-step scheme to lower the error floor of LDPC codes with ADMM penalized decoder.For the undetected errors that cannot be avoided at the decoder side, we modify the code structure slightly to eliminate low-weight code words. For the detected errors induced by small error-prone structures, we propose a post-processing method for the ADMM penalized decoder. Simulation results show that the error floor can be reduced significantly over three illustrated LDPC codes by the proposed two-step scheme. 展开更多
关键词 LDPC codes linear programming decoding alternating direction method of multipliers(ADMM) error floor
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参数化设计减小矩形花键滚刀代用圆弧的误差
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作者 陈英健 辛佳毅 +1 位作者 王时英 吕明 《机械设计与制造》 北大核心 2024年第8期105-108,113,共5页
针对矩形花键滚刀代用圆弧相对于理论法向齿形的误差进行了参数化的程序设计,根据最大误差最小法算法以及回代算法,减小了矩形花键滚刀齿形代用圆弧的误差、获得了合理的代用圆弧的圆心坐标及半径值以及缩短了设计周期。其基本方法:首... 针对矩形花键滚刀代用圆弧相对于理论法向齿形的误差进行了参数化的程序设计,根据最大误差最小法算法以及回代算法,减小了矩形花键滚刀齿形代用圆弧的误差、获得了合理的代用圆弧的圆心坐标及半径值以及缩短了设计周期。其基本方法:首先计算出矩形花键滚刀法向齿形的坐标点公式,然后用双圆弧来代替理论齿形,推导出双圆弧拟合公式。之后基于最大误差最小法算法和回代算法,最后以ObjectARX为开发工具,基于C#.NETAPI的技术,利用优化后的代用圆弧的圆心坐标和半径值以及数据库中的其他相关参数完成矩形花键滚刀法向齿形图的绘制,并且自主研发设计出一套集矩形花键滚刀参数设计、滚齿自动加工参数仿真、干涉参数验算和滚齿数据处理控制于一体的通用矩形花键滚刀参数人性化自动设计绘制平台,实现渐变和矩形状的花键法向滚刀的滚齿参数自动化绘制设计。 展开更多
关键词 矩形花键滚刀 代用圆弧 齿形误差 参数化设计
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电力环保型混合绝缘气体配气方法优化 被引量:1
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作者 董杰 杨博 +2 位作者 伊国鑫 何海川 马乐 《中国电力》 CSCD 北大核心 2024年第6期102-109,共8页
目前电力系统环保型SF_(6)/CF_(4)混合绝缘气体在GIS设备上的配气成本较高,现场选择过充SF_(6)气体以保证其绝缘和灭弧性能,不符合使用该混合气体以实现环保和防液化的目的。为此,提出了基于单一质量流量控制器的环保型SF_(6)/CF_(4)混... 目前电力系统环保型SF_(6)/CF_(4)混合绝缘气体在GIS设备上的配气成本较高,现场选择过充SF_(6)气体以保证其绝缘和灭弧性能,不符合使用该混合气体以实现环保和防液化的目的。为此,提出了基于单一质量流量控制器的环保型SF_(6)/CF_(4)混合绝缘气体分时段交替配气优化方法。通过分时段交替配气即时混匀技术,分析并优化了源于共用气路管道残余气体导致的配气误差,研究了SF_(6)气体输出时间修正技术及最末时段时间再分配方法,进一步降低了充入气体混合比误差。模拟实验表明,该方法的即时混合比与24 h后混合比相对于目标值偏差均小于±0.5个百分点,符合DL/T 2243—2021标准要求。 展开更多
关键词 SF_(6)/CF_(4)混合气体 分时段交替配气 混合比误差控制 即时混匀
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基于改进稀疏重构模型的声学层析温度分布重建
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作者 董祥虎 张立峰 《计量学报》 CSCD 北大核心 2024年第6期834-841,共8页
为进一步提高基于声学层析成像的温度分布重建精度,引入了一种偏差较小的误差函数(ERF)对稀疏重构模型进行改进,并使用迭代重加权算法对模型进一步优化,最后采用交替方向乘子算法(ADMM)对模型进行求解,从而完成温度分布重建。进行了仿... 为进一步提高基于声学层析成像的温度分布重建精度,引入了一种偏差较小的误差函数(ERF)对稀疏重构模型进行改进,并使用迭代重加权算法对模型进一步优化,最后采用交替方向乘子算法(ADMM)对模型进行求解,从而完成温度分布重建。进行了仿真与实验测试,并与LASSO、ART及Landweber算法进行比较,仿真实验中基于ERF模型的温度分布重建质量最优,其平均相对误差及均方根误差分别为0.1%和0.14%;实验测试中,其设定温度点重建温度误差绝对值的平均值最小,为0.043%,明显小于其它3种算法。 展开更多
关键词 温度测量 声学层析成像 稀疏重构 误差函数 迭代重加权算法 交替方向乘子算法
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双机频率域交替闪烁的协同相参信号处理方法
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作者 张亚男 王娜 +1 位作者 董乔龙 张劲东 《航空科学技术》 2024年第6期86-95,共10页
多机协同探测从空域方面扩展了雷达辐射波形的复杂度,频率域交替闪烁为空战场强对抗复杂电磁环境下空、时、频域高度隐蔽提供了多维手段。针对双机编队频率域交替闪烁探测模式下距离—多普勒二维相参处理,本文提出了一种交替方向乘子法(... 多机协同探测从空域方面扩展了雷达辐射波形的复杂度,频率域交替闪烁为空战场强对抗复杂电磁环境下空、时、频域高度隐蔽提供了多维手段。针对双机编队频率域交替闪烁探测模式下距离—多普勒二维相参处理,本文提出了一种交替方向乘子法(ADMM)框架下嵌套多点欠定系统聚焦求解(MFOCUSS)的相位误差估计和二维场景重构方法。仿真结果表明,该方法能够精确估计双机雷达系统频率源引入的固有相位误差,同时对大间隔的双机频率能够进行有效地相参积累和二维场景重构。通过研究,本文设计一种新的双机协同探测工作模式,解决了双机频率域闪烁探测模式下的相位校正和场景重建问题,为复杂电磁环境下协同探测提供了信号处理方法。 展开更多
关键词 双机协同探测 相参积累 稀疏重构 系统相位误差 交替方向乘子法
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变电站交直流轮换试验不间断电源装置研究
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作者 王辉煌 张俊康 +2 位作者 陈祥坚 叶华 王志春 《农村电气化》 2024年第10期81-84,共4页
变电站日常运维中,在固定的维护周期内,需要在不同电源之间切换,以确保双电源的可使用性、安全性以及完整性。虽然是双电源,但是在2种电源来回切换之间还是存在短暂的断电。文章结合现场实际进行分析,研究变电站交直流轮换试验不间断电... 变电站日常运维中,在固定的维护周期内,需要在不同电源之间切换,以确保双电源的可使用性、安全性以及完整性。虽然是双电源,但是在2种电源来回切换之间还是存在短暂的断电。文章结合现场实际进行分析,研究变电站交直流轮换试验不间断电源装置,设计供电旁路,有效避免变电站交直流系统轮换过程中出现间接性停电与设备冲击,同时设置完善电气闭锁逻辑,避免误操作导致的电源短路合环事故。 展开更多
关键词 变电站 轮换试验 不间断电源 电气防误
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An Error Recoverable Structure Based on Complementary Logic and Alternating-Retry
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作者 江建慧 《Journal of Computer Science & Technology》 SCIE EI CSCD 2005年第6期885-894,共10页
Modern VLSI circuits provide adequate on-chip resources. So that online testing and retry integrated into a chip are absolutely necessary for system-on-a-chip technology. This paper firstly proposes a general online t... Modern VLSI circuits provide adequate on-chip resources. So that online testing and retry integrated into a chip are absolutely necessary for system-on-a-chip technology. This paper firstly proposes a general online testing plus retrying structure. Obviously, although retry can mask transient or intermittent faults, it is useless for handling permanent faults generally. To solve this problem, this paper presents a novel dual modular redundancy (DMR) structure using complementary logic--alternating-complementary logic (CL-ACL) switching mode. During error-free operation, the CL-ACL structure operates by complementary logic mode. After an error is detected, it retries by alternating logic mode. If all errors belong to single or multiple temporary 0/1-error or stuck-at-error produced by one module, then these errors can be corrected effectively. The results obtained from the simulation validate the correctness of the CL-ACL structure. Analytic results show that the delay of the CL-ACL structure is dramatically less than that of a DMR structure using alternating-complementary logic mode. 展开更多
关键词 error recovery fault tolerance complementary logic alternating-retry temporary error stuck-at-error
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TDI CCD交错拼接推扫相机严格几何模型构建与优化 被引量:8
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作者 孟伟灿 朱述龙 +3 位作者 曹闻 朱永丰 高翔 曹帆之 《测绘学报》 EI CSCD 北大核心 2015年第12期1340-1350,共11页
时间延迟积分电荷耦合器件(TDI CCD)交错拼接推扫相机,是指焦平面上交错成两行排列多个TDI CCD阵列,并采用推扫成像方式的光学相机。为兼顾空间分辨率与地面覆盖宽度,当前较多的高分辨率光学遥感卫星都搭载了此类相机。本文总结了此类... 时间延迟积分电荷耦合器件(TDI CCD)交错拼接推扫相机,是指焦平面上交错成两行排列多个TDI CCD阵列,并采用推扫成像方式的光学相机。为兼顾空间分辨率与地面覆盖宽度,当前较多的高分辨率光学遥感卫星都搭载了此类相机。本文总结了此类相机的成像原理和特点,基于成像瞬间多片CCD共享一套外方位元素的特点构建了该类相机的"整体几何模型"。针对定位过程中的外部误差和内部误差,基于整体几何模型设计了相应的内外误差补偿方案,对该类相机几何模型的优化进行了研究。以8片TDI CCD交错拼接的天绘一号(TH-1)卫星高分相机原始影像为试验数据设计了多组试验对本文方法进行验证。结果表明:本文的整体几何模型可严格描述该类相机的原始几何物像关系;仅进行外部误差补偿时,影像定位精度显著提升,但各分片CCD影像残留有不同的系统误差;仅进行内部误差补偿时,影像定位精度没有显著提升,但各分片CCD影像定位精度的一致性得到明显改善;对内部、外部误差均补偿后,影像在X、Y、Z方向的定位精度皆优于2m,且各分片CCD影像定位精度具备一致性;将计算出的内部误差补偿参数应用于成像时间间隔22d的其他多景影像时仍达到了同样的定位精度。 展开更多
关键词 交错拼接 推扫式相机 严格几何模型 外部误差补偿 内部误差补偿
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三维荧光二阶校正法快速测定人尿样中奥沙普秦含量 被引量:8
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作者 于丽丽 吴海龙 +4 位作者 付海燕 于永杰 刘亚娟 卿湘东 俞汝勤 《分析化学》 SCIE EI CAS CSCD 北大核心 2011年第1期27-33,共7页
利用三维荧光光谱技术,结合分别基于自加权交替三线性分解(SWATLD)和交替归一加权残差(ANWE)算法的二阶校正方法,直接快速测定人体样液中以及萘丁美酮或萘普生干扰共存下奥沙普秦的含量。利用本方法的"二阶优势",在尿液内源... 利用三维荧光光谱技术,结合分别基于自加权交替三线性分解(SWATLD)和交替归一加权残差(ANWE)算法的二阶校正方法,直接快速测定人体样液中以及萘丁美酮或萘普生干扰共存下奥沙普秦的含量。利用本方法的"二阶优势",在尿液内源物质及萘丁美酮或萘普生干扰共存下有效地分辨出奥沙普秦的激发发射荧光光谱。采用SWATLD和ANWE的二阶校正方法得到的复杂背景下奥沙普秦的回收率令人满意,同时对本方法的精密度进行了研究。通过分析品质因子包括灵敏度(SEN)、选择性(SEL)、检出限(LOD)和检测量(LOQ),评估了这两种方法的性能,利用t-检验和椭圆置信区间(ECJR)统计方法对结果进行了校验。结果表明,解析准确可靠,方法快速简便,无需样品预处理,成本低廉,为临床及医药实时快速分析体液中奥沙普秦含量提供了新的定量分析方法。 展开更多
关键词 奥沙普秦 三维荧光光谱 二阶校正 萘丁美酮 萘普生 自加权交替三线性分解 交替归一加权残差算法
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