Optical Fiber Sensor
Mostrando 1-12 de 38 artigos, teses e dissertações.
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1. Prospects for Developing Low-Cost Optical Fiber Sensors for Liquid-Liquid Interface Detection
Abstract This work examines the prospects of a low-cost retroreflection optical sensor system for detection of the interface between two immiscible liquids, for applications in oil separation tanks. The sensor in its simplest configuration comprises a bare fiber optic tip, cleaved at an angle of 90º relative to the longitudinal fiber axis. The device tested
Journal of Microwaves, Optoelectronics and Electromagnetic Applications. Publicado em: 2022
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2. Compensation technique for environmental and light source power variations applied in a polymer optical fiber curvature sensor for wearable devices
Abstract Introduction Polymer optical fibers (POF) are lightweight, present high elastic strain limits, fracture toughness, flexibility in bend, and are not influenced by electromagnetic fields. These characteristics enable the application of POF as curvature sensor and can overcome the limitations of the conventional technologies, especially for wearable a
Res. Biomed. Eng.. Publicado em: 05/03/2018
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3. The force magnitude of a human bite measured at the molar intercuspidation using fiber Bragg gratings
Abstract This study describes a localized method – using optical fiber Bragg gratings (FBGs) – to determine the human bite force at the very moment of occlusion, in maximum intercuspidation. The FBG was encapsulated in a silicone splint between uppers and lowers first molars and avoiding pre-contact with the other teeth in a dentition model. Gypsum denta
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2017-04
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4. Influence of temperature on the refractive index sensitivities of fiber Bragg gratings refractometers
Abstract Effect of cross-sensitivity between temperature and refractive index (RI) was studied using an optical sensor based on Bragg grating inscribed in an etched multi-mode fiber (MMF). RI sensitivities of different modes were used to obtain a linear response and temperature dependence in water:glycerin solutions. Results pointed out that the absolute ave
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2017-04
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5. Analysis of Parameters for a Distributed Temperature Sensing based on Raman Scattering
Abstract This paper presents a theoretical and computational study on the analysis of parameters for distributed temperature sensing in optical fibers, based on spontaneous Raman scattering effect. The parameters studied were the optical power level, the range of frequency modulation and the length of the sensor element, as well as the application of optical
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2017-03
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6. Experimental evaluation of the wind effects on an operating power transmission tower
Abstract Static and dynamic effects on power transmission towers can be evaluated by methodologies available in codes, which suggest the use of linear static analysis. By using numerical simulations, it is possible to observe the strong influence of the geometric nonlinear behavior of transmission cables. Dynamic effects also strongly influence this behavior
REM, Int. Eng. J.. Publicado em: 2016-09
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7. Hardware embedded fiber sensor interrogation system using intensive digital signal processing
The description of an interrogation system for fiber Bragg grating sensors is reported. The full implementation in hardware of the required signal processing is proposed and made publicly available. The hardware description is implemented in a field programmable gate array (FPGA) development kit and the processing units allow one to control an optoelectronic
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2014-12
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8. A technique to package Fiber Bragg Grating Sensors for Strain and Temperature Measurements
This paper reports an effective method of packaging a fiber Bragg grating (FBG) for the simultaneous measurement of temperature and strain. The technique consists of embedding two fiber Bragg grating sensors inside a polymeric material with different geometrical characteristics. The mechanical and thermal characterizations of the optical transducer were perf
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2013-12
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9. Theoretical and experimental comparison between power and degree of polarization based optical fiber current sensors
This paper presents a theoretical and experimental comparison of two techniques of optical fiber current sensors (OFCS) based on the Faraday Effect: the power and the degree of polarization (DOP) methods. The DOP method is shown to be insensitive to state of polarization (SOP) changes induced by environmental conditions. A maximum variation of 0.4% in the DO
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2013-12
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10. Sistema para medida simultânea de temperatura e deformação com redes de Bragg em 800 nm / Simultaneous measurement of temperature and strain using fiber Bragg gratings written at 800 nm
In recent years, fiber Bragg gratings (FBGs) have been frequently used as strain and temperature sensors. Several studies have tackled the problem of distinguishing between these two physical parameters using a dual-wavelength sensor. Although these sensors have shown good results, they have a few drawbacks, one of them being the need for two light sources w
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 01/11/2012
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11. Sistemas de sensores ópticos baseados em fibra óptica de perfil-W dopada com Érbio / Optical sensing systems based on Erbium-doped W-fiber
Depressed-cladding (often referred to as dual-clad or "W"- fiber) fibers with fundamental-mode cutoffs provide high distributed losses at long wavelengths and low losses at short wavelengths. The magnitude of the abrupt transition between low-loss at short wavelengths and high-loss at long wavelengths exceeds 200 dB/km and is found to be extremely sensitive
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 30/07/2012
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12. Sistema de sensoriamento a fibra óptica para determinação da concentração de sacarose e etanol aplicado a amostras de usinas sucroalcooleiras / Determination of sucrose and ethanol concentrations by optical fiber sensor applied to samples of sugarcane bioethanol industry
O monitoramento eficiente dos diversos estágios de uma usina sucroalcooleira é uma característica essencial para aprimoramento do processo, minimizando as perdas e garantindo a qualidade dos produtos. Nesta pesquisa, foi desenvolvido um sensor a fibra óptica baseado em refletometria para determinação da concentração de etanol e sacarose, aplicado ao
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 13/07/2012