Optical frequency domain reflectometry (OFDR) is a research hotspot in fiber optic sensing technology. This technology can be used for strain, vibration and temperature sensing and has great application prospects in fields such as deformation analysis of aerospace components and bridge monitoring. This article analyzes the reasons for strain demodulation errors under large strains.
View Article and Find Full Text PDFWe present a continuous dynamic frequency scanning interferometry (DFSI) measurement method based on motion phase synchronization compensation and calibration. By introducing heterodyne interferometry (HI) synchronization measurement and frequency scanning interferometry (FSI) motion phase compensation, dynamic continuous measurement is achieved and effectively suppresses the distance error introduced by the Doppler effect (DE). Based on this, the influence of the initial optical frequency deviation (OFD) of the tunable laser and the OFD of the HI laser on the dynamic absolute distance measurement (DADM) is analyzed; the relationships between the error of DADM with the variation of the OFD and the target motion parameters are investigated; and the residual DE introduced by the OFD is shown as the fundamental cause of the degradation of the accuracy of DFSI.
View Article and Find Full Text PDFObjective: To study the effect, treatment course and adverse reactions of Ningmitai Capsules (NMT) in the treatment of chronic prostatitis (CP).
Methods: We searched the CNKI, Wanfang, COMDD and VIP databases, Cochrane Library, PubMed, EMBASE and Chinese academic conference papers for related articles before October 2019 on the treatment of CP with NMT, evaluated the quality of the literature with the Jadad Scale, and conducted a meta-analysis using the Stata14 software.
Results: Totally, 20 articles were included in this study, involving 3558 cases of CP, 1807 in the observation group and 1751 as controls.