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991.
Real-time two-dimensional wavelet compression and its application to real-time modeling of ion mobility data 总被引:1,自引:0,他引:1
Real-time data analysis is important in many applications. However, many chemometric algorithms have difficulty processing data in real-time. A novel real-time two-dimensional wavelet compression (WC2) has been developed to compress data as it is acquired from analytical instrumentation. The WC algorithm was enhanced so that data with an arbitrary number of points were compressed, and truncation or padding to a dyadic number was avoided. After compression, the noise level is reduced while useful chemical information is retained. A modified simple-to-use interactive self-modeling mixture analysis (SIMPLISMA) algorithm was applied to the wavelet-compressed data and the model was transformed back to the original representation while leaving the data compressed. The reduced size of the wavelet-compressed data furnished a faster implementation of SIMPLISMA that facilitates real-time acquisition.
This real-time WC2-SIMPLISMA algorithm was applied to the rapid identification of explosives by ion mobility spectrometry (IMS). SIMPLISMA resolved concentration profiles and component spectra were displayed simultaneously while the data was acquired from an ion mobility spectrometer with a LabVIEW virtual instrument (VI). 相似文献
992.
XU Dachuan~ HAN Jiye~ & DU Dongle~ . College of Applied Sciences Beijing University of Technology Beijing China . Institute of Applied Mathematics Academy of Mathematics Systems Science Chinese Academy of Sciences Beijing China . Faculty of Administration University of New Brunswick P.O.Box Fredericton NB EB A Canada 《中国科学A辑(英文版)》2005,48(9)
We develop improved approximation algorithms for two NP-hard problems: the dense-n/2-subgraph and table compression.Based on SDP relaxation and advanced rounding techniques,we first propose 0. 5982 and 0. 5970-approximation algorithms respec- tively for the dense-n/2-subgraph problem (DSP) and the table compression problem (TCP). Then we improve these bounds to 0. 6243 and 0. 6708 respectively for DSP and TCP by adding triangle inequalities to strengthen the SDP relaxation.The results for TCP beat the 0. 5 bound of a simple greedy algorithm on this problem,and hence answer an open question of Anderson in an affirmative way. 相似文献
993.
This paper concerns a new Lagrangian Discontinuous Galerkin‐type method to solve 2D fluid flows on unstructured meshes. By using a basis of Bernstein polynomials of degree m in each triangle, we define a diffusion process which ensures positivity and stability of the scheme. The discontinuities of the physical variables at the interfaces between cells are solved with an acoustic Riemann solver. A remeshing/remapping process is performed with a particle method: the remapping is locally conservative and its accuracy can be adapted to the accuracy of the numerical method. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
994.
堆积颗粒系统中颗粒级配的优化 总被引:3,自引:0,他引:3
堆积颗粒系统中的颗粒级配在许多产品的生产中起着重要的作用,它不仅对产品的最终性质有很大影响,而且对许多工艺性质起决定作用.此文首先以不定型耐火材料生产中如何选取合理颗粒级配为背景,把紧密堆积理论与实际生产条件及工艺要求相结合,建立了堆积颗粒系统中颗粒级配的优化模型.然后证明了模型的合理性,并结合模型的特征、针对实际情况构造出了求解该优化模型的算法.计算结果表明所给的优化模型及算法对于堆积颗粒系统中颗粒级配的优化是可行的. 相似文献
995.
The previously proposed procedure for the determination of heats of thermal gas-phase reversible reactions using kinetic spectroscopy
was extended for the case of the formation of two intermediate species with overlapping UV spectra. The model problem was
solved, and the error of the method was estimated. Applicability of the method was shown for the reversible formation of trimethylenemethane
(TMM) and but-1-ene-2,4-diyl from methylene-cyclopropane.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 28–34, January, 1998. 相似文献
996.
高阶p-Laplacian算子的边值问题正解的存在性 总被引:4,自引:0,他引:4
本文主要用锥拉伸锥压缩方法讨论了有关p-Laplacian算子的高阶微分方程 边值问题正解的存在性. 相似文献
997.
998.
分形图像压缩技术的数学基础 总被引:11,自引:0,他引:11
分形图像压缩技术是近年来产生的新的黑种人压缩技术,它以分形几何为数学基础。本文综述了这一技术的基本原理、数学基础及最新进展,包括迭代函数系统理论,迭代函数系统反问题,图像生成算法,基本思想与实现技术等等,同时也提出了一些有待深入研究的方向。 相似文献
999.
1000.
This report is virtually the appendix part of the author‘s previous paper which ineludes the proofs for the theorems and lemmas. 相似文献