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101.
Paulo JP Coelho JL Figueiredo MA 《The Journal of the Acoustical Society of America》2010,128(4):1747-1754
Low noise surfaces have been increasingly considered as a viable and cost-effective alternative to acoustical barriers. However, road planners and administrators frequently lack information on the correlation between the type of road surface and the resulting noise emission profile. To address this problem, a method to identify and classify different types of road pavements was developed, whereby near field road noise is analyzed using statistical learning methods. The vehicle rolling sound signal near the tires and close to the road surface was acquired by two microphones in a special arrangement which implements the Close-Proximity method. A set of features, characterizing the properties of the road pavement, was extracted from the corresponding sound profiles. A feature selection method was used to automatically select those that are most relevant in predicting the type of pavement, while reducing the computational cost. A set of different types of road pavement segments were tested and the performance of the classifier was evaluated. Results of pavement classification performed during a road journey are presented on a map, together with geographical data. This procedure leads to a considerable improvement in the quality of road pavement noise data, thereby increasing the accuracy of road traffic noise prediction models. 相似文献
102.
Trigueiro João Paulo C. Figueiredo Rute C. Rojo Javier Viana Renato M. R. Schnitzler Mariane C. Silva Glaura G. 《Journal of Solid State Electrochemistry》2016,20(7):1991-2000
Journal of Solid State Electrochemistry - Carbon nanotubes (CNTs) were surface-modified by a glycodendrimer with four glucose units (4-Gl). Electrodes for supercapacitors based on CNT/4-Gl hybrids... 相似文献
103.
All-silica nanofluidic devices for DNA-analysis fabricated by imprint of sol-gel silica with silicon stamp 总被引:1,自引:0,他引:1
Mikkelsen MB Letailleur AA Søndergård E Barthel E Teisseire J Marie R Kristensen A 《Lab on a chip》2012,12(2):262-267
We present a simple and cheap method for fabrication of silica nanofluidic devices for single-molecule studies. By imprinting sol-gel materials with a multi-level stamp comprising micro- and nanofeatures, channels of different depth are produced in a single process step. Calcination of the imprinted hybrid sol-gel material produces purely inorganic silica, which has very low autofluorescence and can be fusion bonded to a glass lid. Compared to top-down processing of fused silica or silicon substrates, imprint of sol-gel silica enables fabrication of high-quality nanofluidic devices without expensive high-vacuum lithography and etching techniques. The applicability of the fabricated device for single-molecule studies is demonstrated by measuring the extension of DNA molecules of different lengths confined in the nanochannels. 相似文献
104.
Rubens Figueiredo Camargo Edmundo Capelas de Oliveira Jayme Vaz Jr. 《Mathematical Physics, Analysis and Geometry》2012,15(1):1-16
The classical Mittag-Leffler functions, involving one- and two-parameter, play an important role in the study of fractional-order
differential (and integral) equations. The so-called generalized Mittag-Leffler function, a function with three-parameter
which generalizes the classical ones, appear in the fractional telegraph equation. Here we introduce some integral transforms
associated with this generalized Mittag-Leffler function. As particular cases some recent results are recovered. 相似文献
105.
Hidalgo C Silva C Carreras BA van Milligen B Figueiredo H García L Pedrosa MA Gonçalves B Alonso A 《Physical review letters》2012,108(6):065001
The dynamical coupling between density gradients and particle transport has been investigated using similar experimental tools in the plasma boundary of different tokamak (JET, ISTTOK) and stellarator (TJ-II) devices, showing that the size of turbulent events is minimum in the proximity of the most probable density gradient. Experimental results were found to be consistent with results from two very different models of plasma turbulence and transport. The present findings, common to several plasma devices, suggest the importance of self-regulation mechanisms between plasma transport and gradients in fusion devices. 相似文献
106.
Stochastic derivations of the Schrödinger equation are always developed on very general and abstract grounds. Thus, one is never enlightened which specific stochastic process corresponds to some particular quantum mechanical system, that is, given the physical system—expressed by the potential function, which fluctuation structure one should impose on a Langevin equation in order to arrive at results identical to those comming from the solutions of the Schrödinger equation. We show, from first principles, how to write the Langevin stochastic equations for any particular quantum system. We also show the relation between these Langevin equations and those proposed by Bohm in 1952. We present numerical simulations of the Langevin equations for some quantum mechanical problems and compare them with the usual analytic solutions to show the adequacy of our approach. The model also allows us to address important topics on the interpretation of quantum mechanics. 相似文献
107.
108.
We prove the generalized $$L^p$$ -Poincaré inequalities and Sobolev type inequalities on graphs with polynomial volume growth. They are optimal on Vicsek graphs. 相似文献
109.
Claudianor O. Alves Daniel C. de Morais Filho Giovany M. Figueiredo 《Mathematical Methods in the Applied Sciences》2019,42(14):4862-4875
In this work, we prove the existence of positive solution for the following class of problems where λ>0 and is a potential satisfying some conditions. Using the variational method developed by Szulkin for functionals, which are the sum of a C1 functional with a convex lower semicontinuous functional, we prove that for each large enough λ>0, there exists a positive solution for the problem, and that, as λ→+∞, such solutions converge to a positive solution of the limit problem defined on the domain Ω=int(V?1({0})). 相似文献
110.