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91.
Kalman滤波法消除光谱连续背景的研究 总被引:1,自引:0,他引:1
本文研究了Kalman滤波法消除光谱连续背景,以电感耦合等离子体原子发射光谱法测量氧化铽中La,Er,Gd,Dy,Du和Tm为例研究了不同背景情况下的结果。用新息序列的平均平方和正交自相关系数超过出信度极限以外数为评价函数,可评价所估计的背景形状,是一种不用测背景,用计算方法消除光谱连续背景的好方法,本方法不仅适用于电感耦合等离子体原子发射光谱,对分光光度,原子等原则上都可适用。 相似文献
92.
Mark J. Ablowitz Gino Biondini Sarbarish Chakravarty Rudy L. Horne 《Optics Communications》1998,150(1-6):305-318
Collision-induced timing shifts in a wavelength-division multiplexed soliton system are computed when damping, amplification, filtering and positive dispersion management following the loss profile are included. A statistical analysis is presented which takes into account the resulting effect of the large number of collisions occurring in the fiber. Analytic expressions are derived for the root mean square timing jitter and the maximum length of error-free transmission with an arbitrary number of channels. An extensive analysis of system performance corresponding to situations with and without filters and/or dispersion management is carried out. 相似文献
93.
Relationship between the fringe number of the scanning beam and the twin-image noise 总被引:1,自引:0,他引:1
A method of digital filtering for eliminating the twin-image noise of reconstructed images in optical scanning holography is proposed and demonstrated by the example of slit objects. The fringe number of the scanning beam in relation to the twin-image noise is investigated in detail. Some results of computer simulations are obtained. In the far field, the further object scanned by the scanning beam with fewer fringes has lower and flatter amplitude of the twin-image noise for reconstructed images. However, being independent of the fringe number the twin-image noise affects seriously on the reconstruction in the near field. So the twin-image noise should be considered in reconstruction in the near field. 相似文献
94.
基于统计信号处理技术的贝叶斯(Bayes)估计原理,提出一种新的滤波方法。该方法能有效减少散斑条纹图中的噪声,而且仅用一幅散区斑条纹图就能获得准确的条纹相位分布,通过实例说明了该方法的处理过程。 相似文献
95.
Nigel J. Newton 《Journal of statistical physics》2008,133(4):711-737
This paper connects non-equilibrium statistical mechanics and optimal nonlinear filtering. The latter concerns the observation-conditional
behaviour of Markov signal processes, and thus provides a tool for investigating statistical mechanics with partial observations. These allow entropy
reduction, illustrating Landauer’s Principle in a quantitative way.
The joint process comprising a signal and its nonlinear filter is irreversible in its invariant distribution, which therefore
corresponds to a non-equilibrium stationary state of the associated joint system. Macroscopic entropy and energy flows are identified for this state. Since these are driven by observations internal to the system, they do not cause entropy increase, and so the joint system makes statistical mechanical sense in reverse
time.
Time reversal yields a dual system in which the signal and filter exchange roles. Despite the structural similarity of the original and dual systems,
there is a substantial asymmetry in their complexities. This reveals the direction of time, despite the systems being in stationary
states that do not produce entropy.
This work was partially supported by Leverhulme Trust Research Fellowship 2003/0426, by MURI Grant F49620-02-1-0325 (Complex
Adaptive Networks for Co-operative Control), by ARO-MURI Grant DAAD19-00-1-0466 (Data Fusion in Large Arrays of Microsensors
(sensor web)) and by NSF-ITR Grant CCR-0325774 Collaborative Research: New Approaches to Experimental Design and Statistical
Analysis of Genomic and Structural Biological Data from Multiple Sources. 相似文献
96.
A control problem is considered where the coefficients of the linear dynamics are functions of a noisily observed Markov chain. The approximation introduced is to consider these coefficients as functions of the filtered estimate of the state of the chain; this gives rise to a finite-dimensional conditional Kalman filter. A minimum principle and a new equation for an adjoint process are obtained.This research was partially supported by NSERC under Grant A-7964, by the US Air Force Office of Scientific Research under Contract AFOSR-86-0332, and by the US Army Research Office under Contract DAAL03-87-0102.The authors obtained these results during a visit to UCSD by the first author in January 1990. This author wishes to thank Professor D. D. Sworder and his department for their hospitality. 相似文献
97.
98.
P. Cielo 《Optics & Laser Technology》1983,15(3):145-149
Some optical techniques for surface inspection applications are described. Paper texture is analyzed by a frustrated-total-internal-reflection method followed by spatial filtering of the diffracted pattern. Fibre-optics and micro-lenses are used to obtain a rugged and flexible sensor. Similar sensors are used for defect monitoring of roughly-polished surfaces. The practical aspects of sensor manufacture, speckle and vignetting considerations are discussed. 相似文献
99.
J. Casti 《Journal of Optimization Theory and Applications》1978,25(4):591-595
A new conservation law relating basic linear filtering theory quantities is derived. The physical interpretation of the law is given and discussion of its possible uses is presented. 相似文献
100.
R. Kalaba K. Spingarn L. Tesfatsion 《Journal of Optimization Theory and Applications》1981,34(4):541-559
Exact equations are presented for sequentially updating the optimal solution for a discrete-time analog of the basic Sridhar nonlinear filtering problem as the process length increases and new observations are obtained. A tabular method is described for implementing numerically the sequential filtering equations. The accuracy and efficiency of the tabular method are illustrated by means of several numerical examples.Dedicated to R. SridharThe work of R. Kalaba and L. Tesfatsion was partially supported by the National Science Foundation under Grant No. ENG-77-28432 and by the National Institutes of Health under Grant No. GM-23732-03. 相似文献