Optical Fiber
Mostrando 1-12 de 280 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. Analysis Tool for Passive Optical Access Network
Abstract Fiber optic access networks have been considered a definitive solution to the constant need for increasingly higher bandwidths. For this reason, PON (Passive Optical Network) have grown enormously in the recent years, offering different solutions to the end customer, whether it is residential or business. However, the PON project is complex and a ti
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2021-06
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3. Low-Overhead Low-Complexity Carrier Phase Recovery Technique for Coherent Multi-Band OFDM-Based Superchannel Systems Enabled by Optical Frequency Combs
Abstract In this paper, we have designed a low-overhead low-complexity carrier phase tracking scheme for OFDM-based superchannel transmission system enabled by optical frequency combs. In this scheme, taking advantage of the broadband phase coherence provided by optical frequency combs among the OFDM-bands, the carrier phase retrieved from pilot-subcarriers
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2021-03
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4. Optical Fiber Spool Acoustic Wave Resonances Employing a Mach-Zehnder Interferometer in Vacuum Chamber
Abstract The longitudinal, flexural, and torsional modes of acoustical resonances are presented for a long and small thickness cylindrical fiber spool. The fiber spool is built using a monomode optical fiber tightly wound in a helix form around a cylindrical Styropor. The acoustical resonance values are obtained using a Mach Zehnder interferometer with the f
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2020-12
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5. High-Speed Pulse Sequences through Semiconductor Optical Nonlinear Amplification and Buried Fiber Propagation
Abstract Microwave pulse bursts were obtained through optical domain intensity modulated microwave carriers, sliced by cascaded modulator technique, followed by non-linear semiconductor optical amplifier (SOA) pre-chirp. After 3 to 18 km of buried fiber propagation and photo detection, the microwave signals presented increased extinction ratio, up to 36 GHz,
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2020-09
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6. Optical Fiber Coupler Analysis Using Daubechies Wavelets
Abstract This article presents the theoretical analysis of a signal coupling between a proposed Photonic Crystal Fiber (PCF) and a Conventional Fiber with Step Index (CFSI) system. In this analysis, the Finite Element Method (FEM) and Beam Propagation Method (BPM) are applied together with Daubechies wavelets as basis function and described in the mathematic
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2020-09
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7. Assessment of intraocular pressure, macular thickness, retinal nerve fiber layer, and ganglion cell layer thicknesses: ocular parameters and optical coherence tomography findings in attention-deficit/hyperactivity disorder
Objective: To compare intraocular pressure (IOP) and macular, retinal nerve fiber layer (RNFL), and ganglion cell layer (GCL) thicknesses in treatment-naive children with attention-deficit/hyperactivity disorder (ADHD), children with ADHD on regular methylphenidate (MPH) treatment for at least 3 months, and healthy controls. Methods: A total of 58 treatmen
Braz. J. Psychiatry. Publicado em: 2020-06
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8. Implicações do Covid-19 na oftalmologia
Objective: To compare intraocular pressure (IOP) and macular, retinal nerve fiber layer (RNFL), and ganglion cell layer (GCL) thicknesses in treatment-naive children with attention-deficit/hyperactivity disorder (ADHD), children with ADHD on regular methylphenidate (MPH) treatment for at least 3 months, and healthy controls. Methods: A total of 58 treatmen
Rev. bras.oftalmol.. Publicado em: 2020-06
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9. DEVELOPING NEAR INFRARED SPECTROSCOPIC MODELS FOR PREDICTING DENSITY OF Eucalyptus WOOD BASED ON INDIRECT MEASUREMENT
ABSTRACT The objective of this study was to establish multivariate models for the prediction of wood basic density with reference to the values of average density of trees and near infrared (NIR) spectra measured in the breast height. The wood basic density of 39 Eucalyptus clones was determined in the laboratory by means of the mean longitudinal positions o
CERNE. Publicado em: 20/12/2019
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10. Optical coherence tomography findings in bipolar disorder: a preliminary receiver operating characteristic analysis on ganglion cell layer volume for diagnosis
Abstract Background Optical coherence tomography (OCT) has been recently used to investigate neuropsychiatric disorders. Objective The aim of this study was to compare the retinal nerve fiber layer thickness (RNFLT) and the ganglion cell layer (GCL) volume in patients with type 1 bipolar disorder (BPD1, diagnosed according to DSM 5) to the values in heal
Arch. Clin. Psychiatry (São Paulo). Publicado em: 25/11/2019
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11. Effect of panretinal photocoagulation on the peripapillary retinal nerve fiber layer in diabetic retinopathy patients
OBJECTIVES: To determine the effect of panretinal photocoagulation (PRP) on the peripapillary retinal nerve fiber layer (RNFL) in nonglaucomatous patients with proliferative diabetic retinopathy (PDR). METHODS: This is a prospective, single center, observational study. Thirty-eight eyes of 26 diabetic patients underwent PRP for proliferative diabetic retin
Clinics. Publicado em: 25/11/2019
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12. Reproducibility of retinal and choroidal measurements using swept-source optical coherence tomography in patients with Parkinson’s disease
RESUMO Objetivo: Avaliar a reprodutibilidade das medições da retina e da coroide nas áreas macular e peripapilar utilizando a tomografia de coerência ótica com fonte de varredura pacientes com doença de Parkinson. Métodos: Um total de 63 olhos de 63 pacientes com doença de Parkinson idiopática foram avaliados usando um protocolo 3D de tomografia d
Arq. Bras. Oftalmol.. Publicado em: 28/10/2019