Ultrasonic Pulse
Mostrando 1-12 de 32 artigos, teses e dissertações.
-
1. Simulation of Current Pulses and Sound Waves Resulting from Partial Discharges in a Needle-Plane Geometry in Air
Abstract Partial discharges can occur in different types of electric equipment and cause progressive insulation deterioration, so there is interest in monitoring partial discharges for assessing the state of the isolation of an electric system and to predict failures. Techniques to detect partial discharges, such as detecting ultrasonic emission, have been p
Journal of Microwaves, Optoelectronics and Electromagnetic Applications. Publicado em: 2022
-
2. Avaliação teórico-experimental da resistência à compressão de concretos através de ensaios não destrutivos
RESUMO Na avaliação de estruturas degradadas é comum a necessidade de se determinarem propriedades mecânicas de estruturas de concreto sem dispor dos dados de projeto. Propriedades como resistência à compressão e módulo de elasticidade, por exemplo, são importantes nessa análise. No entanto, a extração de testemunhos para avaliação laboratorial
Matéria (Rio J.). Publicado em: 25/11/2019
-
3. ULTRASOUND-ASSISTED TRANSESTERIFICATION OF SOYBEAN OIL USING COMBI-LIPASE BIOCATALYSTS
Abstract We applied ultrasonic technology for the transesterification of soybean oil catalyzed by a mixture of lipases (combi-lipase: 75 % Novozym 435; 10 % Lipozyme TL-IM; and 15 % Lipozyme RM-IM), verifying the effects of ultrasonic amplitude, pulse conditions, the ethanol:oil molar ratio, enzyme concentration, and the influence of solvent (tert-butanol on
Braz. J. Chem. Eng.. Publicado em: 30/09/2019
-
4. Aceite residual automotriz como aditivo en mezclas de hormigón: Si es factible su uso
ABSTRACT Finding a use for Automotive Residual Oil (ARO) is preponderant for society, since one liter of this liquid is capable of contaminating one million liters of drinking water, without counting the damages to agricultural soils and groundwater. The purpose of this work is to study the physical and mechanical properties of concrete by incorporating ARA
Matéria (Rio J.). Publicado em: 10/06/2019
-
5. A magneto-motive ultrasound platform designed for pre-clinical and clinical applications
Abstract Introduction Magneto-motive ultrasound (MMUS) combines magnetism and ultrasound (US) to detect magnetic nanoparticles in soft tissues. One type of MMUS called shear-wave dispersion magneto-motive ultrasound (SDMMUS) analyzes magnetically induced shear waves (SW) to quantify the elasticity and viscosity of the medium. The lack of an established pres
Res. Biomed. Eng.. Publicado em: 12/01/2017
-
6. Continuous flow phantom for the calibration of an ultrasonic transit-time flowmeter
INTRODUCTION: Ultrasound Transit-Time flowmeters are based on the fact that the time required for an ultrasound pulse to propagate through a given distance in a moving medium is a function of the vectorial sum of pulse propagation velocity and medium velocity. The most common application of this flowmeter in medicine is in the evaluation of blood flow in art
Rev. Bras. Eng. Bioméd.. Publicado em: 2014-03
-
7. Finite element simulation of laser generated ultrasound waves in aluminum plates
The Laser-Ultrasonic technique uses laser energy to generate ultrasound waves in various solids. This technique allows inspecting large structures. The generated ultrasound wave form is affected by features of laser pulse (wavelength, pulse duration, power density). The goal of this paper is to study the effects of laser parameters (rise time and beam radius
Lat. Am. j. solids struct.. Publicado em: 2014
-
8. Experimentos virtuales sobre una mosca vagabunda: más allá de la solución de Neumann
We extend the traditional problem of calculating the distance of travel of a fly that is moving with constant speed along a straight path between two trains that are approaching one another. We found two analytical solutions for the traditional problem and we propose a generalization to the accelerated motion of the trains through a simulation. With this pro
Rev. Bras. Ensino Fís.. Publicado em: 2013-06
-
9. Simulação da propagação de ondas ultrassônicas longitudinais em materiais estruturais aeroespaciais / Simulating the propagation of longitudinal ultrasonic waves in aerospace structural materials
The use of composite materials in the aerospace industry is increasing due to its low ratio between density and mechanical strength. To perform non-destructive testing using ultrasound, it is necessary to know the sound velocity in these materials. It is not always possible to manufacture physical prototypes during the development of a project because of tim
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 10/08/2012
-
10. Reconhecimento de PadrÃes AtravÃs de AnÃlises EstatÃsticas e Fractais Aplicadas a Dados de Ensaios NÃo-Destrutivos / Pattern Recognition by Statistical Fluctuation and Fractal Analyses Applied to Nondestructive Testing Data
In this work a procedure is studied for pattern classification related to different types of data, namely: (1) signals obtained from ultrasonic testing ( pulse-echo technique) and magnetic signals obtained from BarkhÃusen noise in samples of ferritic-pearlitic carbon steel tubes which, due to temperature effects, have shown microstructural changes as conseq
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 19/12/2011
-
11. Estudo sobre fatores influentes nos resultados de ensaios não destrutivos em concreto endurecido / Study on influential factors on the results of nondestructive testing in hardened concrete
O avanço tecnológico recente tem proporcionado significativas contribuições para a engenharia civil, com destaque especial para os ensaios não destrutivos utilizados nas estruturas de concreto armado. Usualmente, a propriedade mais avaliada do concreto é a resistência à compressão, porém, dentre outras características, a durabilidade exerce expres
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 15/08/2011
-
12. Ultrasonic inspection of AA6013 laser welded joints
Interest in laser beam welding for aerospace applications is continuously growing, mainly for aluminum alloys. The joints quality is usually assessed by non-destructive inspection (NDI). In this work, bead on plate laser welds on 1.6 mm thick AA6013 alloy sheets, using a 2 kW Yb-fiber laser were obtained and inspected by pulse/echo ultrasonic phased-array te
Materials Research. Publicado em: 26/08/2011