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In this paper, a reflective semiconductor optical amplifier (RSOA) is configured to demodulate dynamic spectral shifts of a fiber Bragg grating (FBG) dynamic strain sensor. The FBG sensor and the RSOA source form an adaptive fiber cavity laser. As the reflective spectrum of the FBG sensor changes due to dynamic strains, the wavelength of the laser output shifts accordingly, which is subsequently converted into a corresponding phase shift and demodulated by an unbalanced Michelson interferometer. Due to the short transition time of the RSOA, the RSOA-FBG cavity can respond to dynamic strains at high frequencies extending to megahertz. A demodulator using a PID controller is used to compensate for low-frequency drifts induced by temperature and large quasi-static strains. As the sensitivity of the demodulator is a function of the optical path difference and the FBG spectral width, optimal parameters to obtain high sensitivity are presented. Multiplexing to demodulate multiple FBG sensors is also discussed.
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http://dx.doi.org/10.1364/AO.55.002752 | DOI Listing |
Adv Sci (Weinh)
September 2025
School of Control Science and Engineering, Shandong University, Jinan, 250061, China.
Real-time and accurate temperature monitoring has been widely recognized in both academia and industry to ensure battery operation safety. Traditional techniques are generally limited to incomplete information caused by discrete sampling points. Hence, the spiral-serpentine distributed optical fiber sensor (DOFS) layout is presented to realize in-situ full-range temperature measurement.
View Article and Find Full Text PDFInt J Radiat Oncol Biol Phys
August 2025
Department of Radiation Oncology, Mayo Clinic, Rochester, MN, USA; Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN, USA. Electronic address:
Purpose: Poly ADP ribose polymerase inhibitors (PARPi) are being combined with photon and proton radiotherapy in clinical trials. We sought to investigate mechanisms of PARPi radiosensitization at varying linear energy transfer (LET) levels after observing an extreme normal tissue response in an 18-year-old with high grade glioma without a germline alteration predictive of heightened radiosensitivity treated with veliparib and proton therapy.
Experimental Design: BRCA1/2 wild-type non-cancerous and cancerous cells were treated with PARPi plus photons or protons at the entrance (ENT, dose-averaged LET [LETd] 2.
Materials (Basel)
August 2025
Shandong Key Laboratory of Civil Engineering Disaster Prevention and Mitigation, Shandong University of Science and Technology, Qingdao 266590, China.
The increasing depth of coal mine construction has led to complex geological conditions involving high ground stress and elevated groundwater levels, presenting new challenges for water-sealing technologies in rock microfissure grouting. This study investigates ultrafine cement grouting in microfissures through systematic analysis of slurry properties and grouting simulations. Through systematic analysis of ultrafine cement grout performance across water-cement (W/C) ratios, this study establishes optimal injectable mix proportions.
View Article and Find Full Text PDFGels
July 2025
Department of Electrical Engineering, College of Science and Technology, University of Nottingham Ningbo China, Ningbo 315100, China.
To prolong the service life of asphalt pavement and reduce its maintenance cost, a fiber Bragg grating (FBG) sensor encapsulated in carboxylated carbon nanotube (CNT-COOH)-modified gel material suitable for strain monitoring of asphalt pavement was developed. Through tensile and bending tests, the effects of carboxylated carbon nanotubes on the mechanical properties of gel materials under different dosages were evaluated and the optimal dosage of carbon nanotubes was determined. Infrared spectrometer and scanning electron microscopy were used to compare and analyze the infrared spectra and microstructure of carbon nanotubes before and after carboxyl functionalization and modified gel materials.
View Article and Find Full Text PDFWe propose a shape-space coordinate prediction model for multi-core fiber Bragg grating (MCFBG) sensors, which integrates pretraining and transfer learning strategies with deep learning architectures. The model establishes an end-to-end mapping relationship from the center wavelength data of MCFBGs to their corresponding shape-space coordinates, which improves the accuracy of MCFBG-based shape sensing while reducing the amount of training data required in experiments. Results show that the best-performing model achieves a median terminal point error with a relative error as low as 0.
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