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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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Some Properties on the Error-Sum Function of Alternating Sylvester Series 被引量:1
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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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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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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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基于交替优化思想的SAR成像位置误差校正
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作者 刘方喜 贾远航 +2 位作者 杨弘毅 牛明宇 刘发林 《微波学报》 北大核心 2025年第6期47-53,共7页
压缩感知由于具有简单高效的特点,已经被广泛应用于合成孔径雷达成像领域。基于压缩感知的合成孔径雷达成像需要建立观测模型,观测模型存在误差将会导致原始场景的重构性能降低。早期的模型大都是假设观察过程的数学模型是精确的,并在... 压缩感知由于具有简单高效的特点,已经被广泛应用于合成孔径雷达成像领域。基于压缩感知的合成孔径雷达成像需要建立观测模型,观测模型存在误差将会导致原始场景的重构性能降低。早期的模型大都是假设观察过程的数学模型是精确的,并在此基础上对原始场景进行重构。但是在实践中,观测位置通常存在误差,因此,需要考虑到雷达观测位置误差带来的影响。与已有考虑位置误差的成像方法不同,文中提出的方法首先重点讨论了观测位置误差对雷达成像带来的影响,然后该方法将观测位置误差作为成像过程的一部分,直接进行误差的估计与补偿,并使用交替优化的思想,交替进行目标重建和观测位置误差的估计与补偿。仿真实验结果表明该方法可以有效地提升成像质量。 展开更多
关键词 压缩感知 观测位置误差 交替优化 合成孔径雷达
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基于ALS的改进频域均衡算法
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作者 马军 程方 +3 位作者 冯姣 张治中 李鹏 赵康 《信息技术》 2025年第12期14-22,共9页
信道仿真器中不同通道之间的幅相不一致会使系统性能恶化,通常的解决方法是在接收信道中加入校准均衡器,以校正信号传输路径中的幅度和相位失真。为了降低通道间的幅相误差、提高信道均衡效果,文中设计了一种正则化交替频域最小二乘优... 信道仿真器中不同通道之间的幅相不一致会使系统性能恶化,通常的解决方法是在接收信道中加入校准均衡器,以校正信号传输路径中的幅度和相位失真。为了降低通道间的幅相误差、提高信道均衡效果,文中设计了一种正则化交替频域最小二乘优化算法(Regularized Alternating Frequency Domain Least Squares Optimization,RA-ALO)。该算法采用正则化来确保矩阵求逆时解的正确性,并使用交替最小二乘法(Alternating Least Squares,ALS)寻找最优解来增强均衡器性能。仿真结果表明,在信道均衡方面,与正则化算法和求伪逆算法相比,该算法具有更低的幅相误差、更优的校准性能。 展开更多
关键词 信道均衡 幅相误差 正则化 交替最小二乘法 信道仿真器
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非精确广义不定邻近交替方向乘子法的收敛性分析
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作者 宋瑞 王依冉 吴中明 《运筹学学报(中英文)》 北大核心 2025年第4期175-190,共16页
交替方向乘子法(ADMM)及其变种广泛应用于求解实际问题,但其有效性极大地依赖于子问题的求解。本文提出一类求解带线性约束可分凸优化问题的非精确广义不定邻近ADMM,其中一个子问题运用基于相对误差的非精确准则近似求解,该准则只涉及... 交替方向乘子法(ADMM)及其变种广泛应用于求解实际问题,但其有效性极大地依赖于子问题的求解。本文提出一类求解带线性约束可分凸优化问题的非精确广义不定邻近ADMM,其中一个子问题运用基于相对误差的非精确准则近似求解,该准则只涉及简单的调节参数;另一个子问题引入不定邻近项。新算法继承了相对误差非精确准则和不定邻近项的优势,能有效提高适用性和求解效率。基于变分不等式框架,分析了算法的收敛性。通过求解图像恢复问题,验证了新算法的有效性。 展开更多
关键词 凸优化 广义交替方向乘子法 非精确 相对误差准则 不定邻近项
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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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基于PLC的交流伺服电机精确控制实时通信系统研究
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作者 靳家琛 王望升 《通信电源技术》 2025年第9期31-33,共3页
随着工业自动化和智能制造的不断发展,伺服电机在高精度控制和动态响应要求下的应用日益广泛。传统伺服系统存在通信延迟和控制精度受限等问题,而可编程逻辑控制器(Programmable Logic Controller,PLC)结合实时通信技术,为解决上述挑战... 随着工业自动化和智能制造的不断发展,伺服电机在高精度控制和动态响应要求下的应用日益广泛。传统伺服系统存在通信延迟和控制精度受限等问题,而可编程逻辑控制器(Programmable Logic Controller,PLC)结合实时通信技术,为解决上述挑战提供新的思路。因此,研究基于PLC的交流伺服电机精确控制实时通信系统,建立适用于PLC控制的运动控制模型,提出伺服驱动自动调整策略,设计双向通信同步集成方案,引入误差补偿与动态优化方法。经实验验证,该系统在位置精度、响应时间、负载适应度以及通信延迟等方面较传统系统均有大幅改善,为工业自动化、智能化发展贡献力量。 展开更多
关键词 可编程逻辑控制器(PLC) 交流伺服电机 运动控制 实时通信 误差补偿
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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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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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