Optical Fiber Sensors
Mostrando 1-12 de 32 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. Monitoring structures with optical fibers: infiltration detection
ABSTRACT The use of sensors and optical fibers for monitoring structures is continuously growing. Strains, displacements, accelerations, temperatures are just a few of the monitoring possibilities. In the case of dam structures, concrete face rockfill dams constitute a type of structures where the monitoring of water infiltrations is of particular interest.
An. Acad. Bras. Ciênc.. Publicado em: 2018-04
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3. 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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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. Thermal Monitoring of Photovoltaic module using Optical Fiber Sensors
Abstract This paper proposes the use of fiber Bragg gratings (FBG) in thermal monitoring of photovoltaic (PV) modules. Results acquired from FBG sensors were compared with two commonly used temperature sensing techniques in PV modules: PT100 sensors and infrared cameras. The experiments were performed using a PV module in actual operating conditions (varying
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2016-12
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6. 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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7. 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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8. 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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9. 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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10. Estudo da viabilidade para fabricação de fibra óptica polimérica (FOP) por extrusão vertical / Study of the feasibility on manufacturing polymeric optical fiber (POF) by vertical extrusion
Polymeric optical fibers (POF) presents some advantages compared to the glass optical fibers as flexibility, higher numerical aperture (NA), ease in handling and connecting due to their larger diameter and lower cost manufacturing and installation. However, due to their larger transmission losses compared to the main applications of glass fibers, POF are lim
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 15/08/2011
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11. Interferômetros recuperadores de baixa tensão de meia onda para sistemas interferométricos de luz branca utilizando moduladores eletro-ópticos. / Low half wave voltage recovery interferometers for white light interferometry systems using electrooptic modulators.
O trabalho tem por objetivo o estudo e o desenvolvimento de interferômetros recuperadores com baixa tensão de meia onda utilizando moduladores eletro-ópticos para serem aplicados em sistemas Interferométricos de luz branca. Ele dá continuidade às pesquisas do autor em seu mestrado, em que foi desenvolvido e testado um sistema de sensoriamento eletro-ó
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 01/08/2011
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12. MONITORING FLEXIBLE RISERS WITH OPTICAL FIBER SENSORS / MONITORAMENTO DE RISERS FLEXÍVEIS COM SENSORES A FIBRA ÓPTICA
The interest in structural health monitoring of flexible risers has grown significantly in recent years. For ducts that are already reaching their design life, monitoring systems can provide early warnings of potential failures and also assist the operator in scheduling downtime. Different techniques are being tested by operators of flexible pipes such as au
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 07/04/2011