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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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电力环保型混合绝缘气体配气方法优化
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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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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 polynomialfitting results and its error analysis are given. Because it’s difficult generally to get a propell... A Chebyshev fitting way for a propeller atlas across four quadrants is discussed. As an example, Chebyshev polynomialfitting results and its error analysis are given. Because it’s difficult generally to get a propeller atlas across four quadrants,a wayis used to construct an alternative with higher accuracy based on the properties. As an application example, an alternative forthe propeller property of a Deep Submergence Vebicle across four quadrants is given practically and a simulation model of 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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基于目标分解的逐次迭代逼近混合预编码算法
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作者 刘雯雯 吴君钦 谢子宣 《计算机工程与设计》 北大核心 2023年第10期2888-2893,共6页
为改善大规模毫米波多输入多输出的性能,提出一种基于目标分解的逐次迭代逼近混合预编码算法。基于目标分解,通过采用逐次迭代逼近、交替优化的求解方法和加入中继设备扩大传输范围的模型设计方法,研究混合预编码矩阵设计的问题。仿真... 为改善大规模毫米波多输入多输出的性能,提出一种基于目标分解的逐次迭代逼近混合预编码算法。基于目标分解,通过采用逐次迭代逼近、交替优化的求解方法和加入中继设备扩大传输范围的模型设计方法,研究混合预编码矩阵设计的问题。仿真结果表明,所提算法可以获得更加理想的系统均方误差和总和速率,其性能逼近理想预编码性能,具有有效性和可靠性。 展开更多
关键词 毫米波 混合预编码 目标分解 逐次迭代逼近 交替优化 均方误差 总和速率
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基于CFEM的D-N交替算法的一类凹角区域各向异性外问题求解
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作者 涂明玥 《吉首大学学报(自然科学版)》 CAS 2023年第4期31-38,共8页
基于曲边有限元(CFEM)的自然边界元理论,设计出带CFEM的D-N交替算法,来解决无穷凹角区域上的各向异性外问题,并给出了近似解与真解之间的误差估计和收敛性.
关键词 各向异性外问题 曲边有限元 D-N交替算法 误差估计
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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:9
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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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编码器换向误码输出原因探讨及鉴相电路改进 被引量:13
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作者 孙祥明 齐明侠 沈蓉 《石油大学学报(自然科学版)》 EI CSCD 北大核心 2005年第4期91-94,共4页
从编码器的结构特点出发,探讨了编码器频繁换向时输出信号中存在误码脉冲的原因。根据编码器输出信号不能同时跳变的特点,设计了一种更简单有效的双向触发鉴相电路。该电路通过标记两相输出信号跳变时刻的状态,经过一定的逻辑与运算,有... 从编码器的结构特点出发,探讨了编码器频繁换向时输出信号中存在误码脉冲的原因。根据编码器输出信号不能同时跳变的特点,设计了一种更简单有效的双向触发鉴相电路。该电路通过标记两相输出信号跳变时刻的状态,经过一定的逻辑与运算,有效地滤除了输出信号中存在的误码脉冲。经实验室应用证明,该电路具有较好的误码滤除效果,为编码器内部电路的改进及其输出信号的数字处理提供了一种新思路。 展开更多
关键词 光电编码器 误码滤除 换向 鉴相电路 改进
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交变光场时空耦合型位移测量系统的研制 被引量:7
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作者 朱革 张超 +2 位作者 付敏 潘帅嘉 雷川 《光学精密工程》 EI CAS CSCD 北大核心 2017年第8期2011-2022,共12页
针对现有光栅精密刻划加工难度大制约测量精度的问题,设计了一种以交变光场为测量媒介的时空耦合线性位移测量系统。该测量系统利用四路正交的交变光场与四组正交的正弦透光面调制耦合形成电行波信号实现高精度位移测量。在对测量系统... 针对现有光栅精密刻划加工难度大制约测量精度的问题,设计了一种以交变光场为测量媒介的时空耦合线性位移测量系统。该测量系统利用四路正交的交变光场与四组正交的正弦透光面调制耦合形成电行波信号实现高精度位移测量。在对测量系统测量原理分析的基础上,建立了该系统的理论模型和误差模型,通过仿真详细分析了该系统在时间相位不正交、空间相位不正交以及结构安装不平行时的误差规律。开展实验验证了一次、二次和四次谐波的产生原因,根据误差来源改进了测量装置的结构,优化了相应的参数。实验结果表明:在180mm测量范围内,用栅距0.6mm的测量系统实现了±0.4μm的测量精度。该测量系统规避了现有光栅精密刻划的问题,结构简单、安装方便,为光学位移测量提供了新思路。 展开更多
关键词 位移测量 交变光场 时空耦合 行波合成 误差分析
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