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31.
We present in this paper a fuzzy clustering algorithm which can handle spatially constraint problems often encountered in pattern recognition. The proposed method is based on the notions of hyperplanes, the fuzzy c-means, and spatial constraints. By adding a spatial regularizer into the fuzzy hyperplane-based objective function, the proposed method can take into account additionally important information of inherently spatial data. Experimental results have demonstrated that the proposed algorithm achieves superior results to some other popular fuzzy clustering models, and has potential for cluster analysis in spatial domain. 相似文献
32.
Pham TD 《Computer methods and programs in biomedicine》2012,106(3):201-209
Reducing noise in medical images has been an important issue of research and development for medical diagnosis, patient treatment, and validation of biomedical hypotheses. Noise inherently exists in medical and biological images due to the acquisition and transmission in any imaging devices. Being different from image enhancement, the purpose of image restoration is the process of removing noise from a degraded image in order to recover as much as possible its original version. This paper presents a statistically supervised approach for medical image restoration using the concept of multiple-point geostatistics. Experimental results have shown the effectiveness of the proposed technique which has potential as a new methodology for medical and biological image processing. 相似文献
33.
J. Theo Kloprogge Maarten Broekmans Loc V. Duong Wayde N. Martens Liesel Hickey Ray L. Frost 《Journal of Materials Science》2006,41(11):3535-3539
Lecontite, (NH4)Na(SO4).2H2O, was synthesised at room temperature in high purity compared to earlier work with a minor impurity of mascagnite, (NH4)2SO4. Rietveld refinement of the XRD results confirmed the crystal structure and unit cell dimensions as published earlier. Raman
and Infrared spectroscopy, in conjunction with factor group analysis, resulted in a complex pattern of overlapping sulphate,
NH and OH modes. The NH modes υ1 was observed around 2880 cm−1, υ2 around 1700 cm−1 overlapping with water OH-bending modes, υ3 around 3300 cm−1 overlapping with water OH-stretching modes around 3023, 3185 and 3422 cm−1, and υ4 around 1432, 1447 and 1462 cm−1. The sulphate group in the crystal structure displays a decrease in symmetry from Td as evidenced by the activation of the ν1 mode at 982 cm−1 and the ν2 mode around 452 cm−1 in the Infrared spectrum. The υ3 mode shows clear splitting in the infrared spectra with a strong band at 1064 cm−1 accompanied by two shoulders at 1107 and 1139 cm−1. The Raman spectra show three weak bands at 1068, 1109 and 1135 cm−1 with a shoulder at 1155 cm−1. Similar splitting was observed for the υ4 mode around 611 and 632 cm−1 in the Infrared and Raman spectra, respectively. 相似文献
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37.
Jian Wang Tuan Le Vang A. A. Pyrkin S. A. Kolyubin A. A. Bobtsov 《Automation and Remote Control》2018,79(12):2159-2168
We consider the problem of identifying unknown nonstationary piecewise linear parameters for a linear regression model. A new algorithm is proposed that allows, in the case of a number of assumptions on the elements of the regressor, to provide an estimate of unknown non-stationary parameters. We analyze in detail the case with two unknown parameters, which makes it possible to understand the main idea of the proposed approach. We also consider a generalization to the case of an arbitrary number of parameters. We give an example of computer simulation that illustrates the efficiency of the proposed approach. 相似文献
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Srivaro Suthon Psztory Zoltn Le Duong Hung Anh Lim Hyungsuk Jantawee Sataporn Tomad Jaipet 《Holz als Roh- und Werkstoff》2021,79(6):1519-1529
European Journal of Wood and Wood Products - The fundamental material properties of coconut wood cross-laminated timber (CLT) were experimentally evaluated with a focus on the effect of the... 相似文献
40.
Nguyen T. H. Hanh Bui T. Nhung Le T. Hop Le T. Tuyet Duong T. A. Dao Nguyen T. T. Thu Tran Quang Binh 《Lipids》2020,55(6):683-691
Apolipoprotein A-V encoded by apolipoprotein 5 (APOA5) gene plays an important role in lipid metabolism, especially in the regulation of plasma triglycerol levels. The study aimed to evaluate the association of the APOA5-rs662799 polymorphism with dyslipidemia in Vietnamese children and the potential modification of obesity-related traits (body mass index, waist circumference, hip circumference, and waist-to-hip ratio) on this association. A case–control study was conducted with a total of 154 dyslipidemia cases and 389 controls at the age of 6 to 10 recruited at 31 primary schools in Hanoi city of Vietnam. Genotype for APOA5-rs662799 polymorphism was determined by the restriction fragment length polymorphism analysis. The association of APOA5-rs662799 polymorphism with dyslipidemia adjusting for age, sex, residence, and obesity-related traits was analyzed by binary logistic regression analysis. The results showed that in comparison with T/T and T/C carriers, the C/C carriers had a higher concentration of serum TAG in cases (p =0.049). Carriers of the C allele (C/C + T/C) had higher risk for developing dyslipidemia and hypertriglyceridemia than subjects with T/T genotype (odds ratio, OR = 1.7, p =0.0062 and OR = 1.6, p = 0.026, respectively). The association remained significant after adjusting for age, gender, residence, and obesity status (OR = 1.75, p = 0.006 and OR = 1.53, p = 0.049, respectively) or other obesity-related traits. The study suggested that the APOA5-rs662799 polymorphism may be a determinant of dyslipidemia and hypertriglyceridemia in Vietnamese children, independent of obesity-related traits. 相似文献