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Since the dispersive interferometry (DPI) based on optical frequency combs (OFCs) was proposed, it has been widely used in absolute distance measurements with long-distance and high precision. However, it has a serious problem for the traditional DPI based on the mode-locked OFC. The error of measurements caused by using the fast Fourier transform (FFT) algorithm to process signals cannot be overcome, which is due to the non-uniform sampling intervals in the frequency domain of spectrometers. Therefore, in this paper, we propose a new mathematical model with a simple form of OFC to simulate and analyze various properties of the OFC and the principle of DPI. Moreover, we carry out an experimental verification, in which we adopt the Lomb-Scargle algorithm to improve the accuracy of measurements of DPI. The results show that the Lomb-Scargle algorithm can effectively reduce the error caused by the resolution, and the error of absolute distance measurement is less than 12 μm in the distance of 70 m based on the mode-locked OFC.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9318693 | PMC |
http://dx.doi.org/10.3390/s22145403 | DOI Listing |
Arch Public Health
September 2025
Centre for Clinical Research, Region Värmland, Karlstad, 651 85, Sweden.
Background: Physical inactivity, impaired physical mobility and poor mental health are common in the older population and increasing as the population ages. We examined the relationships between physical activity, physical mobility, and mental health in the general population of older adults.
Methods: The study is based on 12 959 men and women aged 70 years or older answering a survey questionnaire sent to a random population sample in Mid-Sweden in 2022 (response rate 66%).
BMC Health Serv Res
September 2025
Institute of General Practice, Rostock University Medical Center, Doberaner Str. 142, Rostock, 18057, Germany.
Background: Post-viral syndromes, including long- and post-COVID, often lead to persistent symptoms such as fatigue and dyspnoea, affecting patients' daily lives and ability to work. The COVI-Care M-V trial examines whether interprofessional, patient-centred teleconsultations, initiated by general practitioners in cooperation with specialists, can help reduce symptom burden and improve care for patients.
Methods: To evaluate the effectiveness of the intervention under routine care conditions, a cluster-randomised controlled trial is being conducted.
Spinal Cord Ser Cases
September 2025
Rehabilitation Sciences Institute, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada.
Study Design: Concurrent mixed methods case series.
Objectives: To examine the feasibility and effect of a peer-facilitated, remote handcycling sport program on physical, psychological, and social health of individuals with spinal cord injury or disease (SCI/D) aged ≥50 years.
Setting: Participants' homes.
Ophthalmic Plast Reconstr Surg
September 2025
Department of Oculoplastic, Orbital & Lacrimal Surgery, Aichi Medical University Hospital. Nagakute, Aichi, Japan.
Purpose: To examine the position of the lower marginal arterial arcade (LMA) along the lower tarsal plate in microscopic specimens, particularly its relationship to anatomical landmarks.
Methods: Central sagittal sections of 27 lower eyelids (12 right, 10 left) from 15 Japanese cadavers (8 males, 7 females; aged 38-88 years, mean 70.5 years) were histologically examined.
Anesth Prog
September 2025
Objective: We aimed to investigate the differences in the lengths and shapes of several preformed nasotracheal tubes (NTTs) among different manufacturers and compare our findings with a previous report.
Methods: Using reference points at the tube tip, the proximal edge of the cuff, and the flexion point, we measured tube lengths for NTTs with inner diameters of 6.5, 7.