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Jon Prez Laraudogoitia 《Studies in History and Philosophy of Science Part B: Studies in History and Philosophy of Modern Physics》2007,38(4):724-731
Atkinson [2006. Losing energy in classical, relativistic and quantum mechanics. in Studies in History and Philosophy of Modern Physics, 38 To appear.] has obtained some new results on supertasks and the violation of conservation laws. I discuss these results here, extending them from a different perspective, which, by focusing on considerations of indeterminism, facilitates the natural introduction in this context of the concept of dynamical attractor. 相似文献
13.
The problem of prediction in time series using nonparametric functional techniques is considered. An extension of the local linear method to regression with functional explanatory variable is proposed. This forecasting method is compared with the functional Nadaraya–Watson method and with finite‐dimensional nonparametric predictors for several real‐time series. Prediction intervals based on the bootstrap and conditional distribution estimation for those nonparametric methods are also compared. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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Algorithm for repairing the damaged images of grain structures obtained from the cellular automata and measurement of grain size
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A. Ramírez-López M. A. Romero-Romo D. Mu oz-Negron S. L pez-Ram rez R. Escarela-P rez C. Duran-Valencia 《矿物冶金与材料学报》2012,19(10):899-907
Computational models are developed to create grain structures using mathematical algorithms based on the chaos theory such as cellular automaton, geometrical models, fractals, and stochastic methods. Because of the chaotic nature of grain structures, some of the most popular routines are based on the Monte Carlo method, statistical distributions, and random walk methods, which can be easily programmed and included in nested loops. Nevertheless, grain structures are not well defined as the results of computational errors and numerical inconsistencies on mathematical methods. Due to the finite definition of numbers or the numerical restrictions during the simulation of solidification, damaged images appear on the screen. These images must be repaired to obtain a good measurement of grain geometrical properties. Some mathematical algorithms were developed to repair, measure, and characterize grain structures obtained from cellular automata in the present work. An appropriate measurement of grain size and the corrected identification of interfaces and length are very important topics in materials science because they are the representation and validation of mathematical models with real samples. As a result, the developed algorithms are tested and proved to be appropriate and efficient to eliminate the errors and characterize the grain structures. 相似文献
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Mutations in CAV3 cause mechanical hyperirritability of skeletal muscle in rippling muscle disease. 总被引:13,自引:0,他引:13
R C Betz B G Schoser D Kasper K Ricker A Ramírez V Stein T Torbergsen Y A Lee M M N?then T F Wienker J P Malin P Propping A Reis W Mortier T J Jentsch M Vorgerd C Kubisch 《Nature genetics》2001,28(3):218-219
Hereditary rippling muscle disease (RMD) is an autosomal dominant human disorder characterized by mechanically triggered contractions of skeletal muscle. Genome-wide linkage analysis has identified an RMD locus on chromosome 3p25. We found missense mutations in positional candidate CAV3 (encoding caveolin 3; ref. 5) in all five families analyzed. Mutations in CAV3 have also been described in limb-girdle muscular dystrophy type 1C (LGMD1C; refs. 6,7), demonstrating the allelism of dystrophic and non-dystrophic muscle diseases. 相似文献
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Omar K. Matar Panagiota Angeli Geoffrey F. Hewitt E. Susana Pérez de Ortiz 《清华大学学报》2006,11(2):202-206
Introduction Liquid-liquid dispersions in agitated vessels are fre-quently used in the chemical industry for conducting operations such as solvent extraction and heterogene-ous reactions. In liquid-liquid two-phase flow systems, usually consisting of an a… 相似文献
18.
Catalina Romero-Ortiz Eduardo Flórez D. Carlos E. Sarmiento 《Journal of Natural History》2020,54(15-16):1025-1043
ABSTRACT Pseudoscorpiones is a mesodiverse order of Arachnida, with more than 3600 described species in the world. Species delimitation is sometimes difficult due to the high variability of some characters, difficulty in finding informative and useful characters for species differentiation and the subjectivity of individual specialists. The aim of this work is to explore and to evaluate the role of morphometric characters in species delimitation within the genus Apolpium (Olpiidae). Measurements of 17 structures of 57 individuals were taken and their length/width ratios calculated. Cluster analyses, principal components analyses, discriminant function analyses and non-metric multidimensional scaling were carried out. The results showed low resolution for the number of species currently recognised in the genus. These results highlight the importance of looking for other morphological characters, and also for a more rigorous assessment of previously used characters for defining species. 相似文献
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Cardona Suárez Carlos Alberto Gutiérrez Valderrama Juliana 《Archive for History of Exact Sciences》2020,74(1):45-75
Archive for History of Exact Sciences - Johannes Kepler dedicated much of his work to discover a law for the refraction of light. Unfortunately, he formulated an incorrect law. Nevertheless, it was... 相似文献
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