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Resampling methods for particle filtering: identical distribution, a new method, and comparable study

Tian-cheng LI,Gabriel VILLARRUBIA,Shu-dong SUN,Juan M. CORCHADO,Javier BAJO

《信息与电子工程前沿（英文）》 2015年第16卷第11期页码 969-984 doi: 10.1631/FITEE.1500199

摘要： Resampling is a critical procedure that is of both theoretical and practical significance for efficient implementation of the particle filter. To gain an insight of the resampling process and the filter, this paper contributes in three further respects as a sequel to the tutorial (Li et al., 2015). First, identical distribution (ID) is established as a general principle for the resampling design, which requires the distribution of particles before and after resampling to be statistically identical. Three consistent metrics including the (symmetrical) Kullback-Leibler divergence, Kolmogorov-Smirnov statistic, and the sampling variance are introduced for assessment of the ID attribute of resampling, and a corresponding, qualitative ID analysis of representative resampling methods is given. Second, a novel resampling scheme that obtains the optimal ID attribute in the sense of minimum sampling variance is proposed. Third, more than a dozen typical resampling methods are compared via simulations in terms of sample size variation, sampling variance, computing speed, and estimation accuracy. These form a more comprehensive understanding of the algorithm, providing solid guidelines for either selection of existing resampling methods or new implementations.

关键词： Particle filter Resampling Kullback-Leibler divergence Kolmogorov-Smirnov statistic

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Crystal modification of rifapentine using different solvents

Kun ZHOU, Jun LI, Jianhong LUO, Dongsheng ZHENG,

《化学科学与工程前沿（英文）》 2010年第4卷第1期页码 65-69 doi: 10.1007/s11705-009-0302-6

摘要： Rifapentine crystals with different habits were prepared by recrystallization from selected solvents, such as methanol, ethanol, chloroform, and acetic acid. Scanning electron microscopy, X-ray powder diffractometry, infrared spectrometry, and differential scanning calorimetry were used to investigate the physicochemical characteristics of the prepared crystals. The comparative dissolution behaviors of the newly developed crystals and of rifapentine without being treated were also studied. Results show that the newly developed crystals were different from each other with respect to physical properties but were identical chemically. Needle-shaped crystals were obtained from methanol, ethanol, and chloroform solvents, and the block-shaped crystals were obtained from acetic acid solvent. X-ray diffraction spectra and differential scanning calorimetry investigation on those developed crystals clearly indicate that rifapentine has different crystal structure modification. When the crystal was obtained from acetic acid, the change of crystal habit was originated from the crystal structure modification. The dissolution rate of newly developed crystals was found to be higher than that of rifapentine without being treated. However, the modified crystal obtained from acetic acid shows the lower dissolution rate than crystals obtained from other solvents.

关键词： identical scanning calorimetry different comparative dissolution structure modification

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Inverse Kinematics Analysis of General 6R Serial Robot Mechanism Based on Groebner Base

WANG Yan, HANG Lu-bin, YANG Ting-li

《机械工程前沿（英文）》 2006年第1卷第1期页码 115-124 doi: 10.1007/s11465-005-0022-7

摘要：

This study presents a solution for the inverse kinematics problem in serial 6R manipulator. Using only seven equations composed of Duffy s four kinematical equations containing three angles and three corresponding angles identical equations instead of the traditional 14 equations, the authors reduced the inverse kinematics problem in the general 6R manipulator to a univariate polynomial with a minimum degree based on the Groebner Base method. From that, they concluded that the maximum number of the solutions is 16, generally. Also, the mathematics mechanization method can be extended to solve other mechanism problems involving nonlinear equations symbolically.

关键词： identical manipulator univariate polynomial mechanism traditional

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The molecular epidemiological study of colistin-only-sensitive strains in multi-drug resistant Acinetobacter baumannii

YANG Li, HAN Lizhong, SUN Jingyong, NI Yuxing, YU Yunsong

《医学前沿（英文）》 2007年第1卷第4期页码 423-428 doi: 10.1007/s11684-007-0083-6

摘要： This paper reported the epidemiology of the colistin-only-sensitive (COS-AB) in a tertiary teaching hospital in China. We analyzed the clinical data of 136 COS-AB isolates from June 2004 to May 2005 and collected 66 . isolates in which 33 strains were COS-AB, and the rest were non-COS-AB. Random amplified polymorphic DNA (RAPD) analysis (primer ERIC2 and 272) showed that all COS-AB were identical, while pulsed-field gel electrophotesis (PFGE) analysis showed two separate genotypes of these COS-AB which were distinctly different from that of non-COS-AB. The COS-AB from burn wards showed the identical PFGE pattern which was distinguished from the genotype of COS-AB in other departments, mainly surgical systems. The cross-infection was severe and strict methods of disinfection and sterilization should be implemented. Meanwhile, the epidemiology of COS-AB in environment and patients should be closely monitored. The PFGE analysis is a reliable method of . typing.

关键词： identical different teaching hospital genotype colistin-only-sensitive