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81.
A non-uniformity correction (NUC) method for an infrared focal plane array imaging system was proposed. The algorithm, based on compressive sensing (CS) of single image, overcame the disadvantages of “ghost artifacts” and bulk calculating costs in traditional NUC algorithms. A point-sampling matrix was designed to validate the measurements of CS on the time domain. The measurements were corrected using the midway infrared equalization algorithm, and the missing pixels were solved with the regularized orthogonal matching pursuit algorithm. Experimental results showed that the proposed method can reconstruct the entire image with only 25% pixels. A small difference was found between the correction results using 100% pixels and the reconstruction results using 40% pixels. Evaluation of the proposed method on the basis of the root-mean-square error, peak signal-to-noise ratio, and roughness index (ρ) proved the method to be robust and highly applicable. 相似文献
82.
In this paper, the effects of atmospheric turbulence on the intensity distribution of a tilted Rectangular Partially Coherent Flat-Topped (RPCFT) beam were studied. An analytical formula for the intensity distribution was derived. POWER In Bucket (PIB) value is calculated numerically. The effects of source parameters – such as correlation length, order of flatness and tilt coefficient – on the intensity were analyzed. Detailed analysis demonstrates that these parameters have an influence on beam propagation properties. The analyses are illustrated by numerical examples and graphs. 相似文献
83.
详细地介绍了辉光放电质谱分析中的质谱干扰如同量异位素、多原子离子和多电荷离子干扰。从同位素选择、高分辨率仪器、碰撞诱导解离、离子源冷却、数学方法校正、放电气体更换和放电气体纯度提高等方面对辉光放电质谱的质谱干扰校正方法的现状进行了评述(引用文献共68篇)。 相似文献
84.
Boundedness and convergence of perturbed corrections for helium-like ions in ground states 下载免费PDF全文
Applying the improved Rayleigh SchrSdinger perturbation theory based on an integral equation to helium-like ions in ground states and treating electron correlations as perturbations, we obtain the second-order corrections to wavefunctions consisting of a few terms and the third-order corrections to energicity. It is demonstrated that the corrected wavefunctions are bounded and quadratically integrable, and the corresponding perturbation series is convergent. The results clear off the previous distrust for the convergence in the quantum perturbation theory and show a reciprocal development on the quantum perturbation problem of the ground state helium-like systems. 相似文献
85.
P. J. Salas 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2008,46(2):365-373
The decoherence effect on Grover algorithm has been studied numerically
through a noise modelled by a depolarizing channel. Two types of error are
introduced characterizing the qubit time evolution and gate application, so
the noise is directly related to the quantum network construction. The
numerical simulation concludes an exponential damping law for the successive
probability of the maxima as time increases. We have obtained an
allowed-error law for the algorithm: the error threshold for the allowed
noise behaves as εth(N) ∼1/N1.1 (N being the
size of the data set). As the power of N is almost one, we consider the
Grover algorithm as robust to a certain extent against decoherence. This law
also provides an absolute threshold: if the free evolution error is greater
than 0.043, Grover algorithm does not work for any number of qubits affected
by the present error model. The improvement in the probability of success,
in the case of two qubits has been illustrated by using a fault-tolerant
encoding of the initial state by means of the [[7,1,3]] quantum code. 相似文献
86.
The procedure of microphase adsorption–spectral correction is applied to the interaction of eosine Y (EO) to the micelles of cetyl trimethyl ammonium bromide (CTAB). The Langmuir aggregation of EO on CTAB occurs owing to microelectrostatic attraction. The results have shown that at pH 3.8, monomeric and micellar aggregates have the structure EO5·CTAB2 and (EO5·CTAB2)39. The adsorption constant of an aggregate is 7.01·105, its molar absorption coefficient is = 8.8·104 liters·mole–1·cm–1 at 550 nm. Application of the aggregation of EO on CTAB gives satisfactory results for quantitative determination of cation surfaceactive agents (surfactants). 相似文献
87.
梯度折射率棒透镜的色差模型 总被引:1,自引:0,他引:1
本文提出一个梯度折射率棒透镜(GRIN-RodLens)的色差模型,并运用本模型合理地解释了在色差测量过程发现的各类色差现象. 相似文献
88.
A relativistic model of independent quarks based on Dirac equation with an equally mixed scalar-vector square root confining
potential is used to compute the quark core contributions to the static properties like magnetic moments, charge radii and
axial vector coupling constant ratios of the baryon octet. The results obtained with appropriate corrections due to centre-of-mass
motion agree fairly well with experimental values. The model is also extended to the study of magnetic moments of the quark
core of baryons in the charmed andb-flavoured sectors and the overall predictions so obtained compare well with other model predictions. 相似文献
89.
Huo R Wehrens R Buydens LM 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2004,169(2):2972-269
The quality of DOSY NMR data can be improved by careful pre-processing techniques. Baseline drift, peak shift, and phase shift commonly exist in real-world DOSY NMR data. These phenomena seriously hinder the data analysis and should be removed as much as possible. In this paper, a series of preprocessing operations are proposed so that the subsequent multivariate curve resolution can yield optimal results. First, the baseline is corrected according to a method by Golotvin and Williams. Next, frequency and phase shift are removed by a new combination of reference deconvolution (FIDDLE), and a method presented by Witjes et al. that can correct several spectra simultaneously. The corrected data are analysed by the combination of multivariate curve resolution with non-linear least square regression (MCR-NLR). The MCR-NLR method turns out to be more robust and leads to better resolution of the pure components than classic MCR. 相似文献
90.
Reactions between Fe(II) and dibromo-o-nitrophenylfluorone (DBNPF) and also between Zn(II) and DBNPF are sensitive at pH 9 in the presence of Triton X-100. The simultaneous determination of the Fe and Zn content by the spectral correction technique is shown. For analysis of water, plant, and hair samples, the reaction is selective in the presence of triethanolamine and thiourea. The recovery of Fe and Zn is between 88 and 108% and between 90.5 and 107%, and their relative standard deviation is less than 10 and 5.9%, respectively. The method makes it possible to carry out analysis of the solutions of two complexes and easily determine their characteristic constants such as the composition ratio, molar extinction ratio (), and stepwise stability constant (K). 相似文献