This paper presents a complete analysis of the positional errors of terrestrial laser scanning (TLS) data based on spherical statistics and 3D graphs. Spherical statistics are preferred because of the 3D vectorial nature of the spatial error. Error vectors have three metric elements (one module and two angles) that were analyzed by spherical statistics. A study case has been presented and discussed in detail. Errors were calculating using 53 check points (CP) and CP coordinates were measured by a digitizer with submillimetre accuracy. The positional accuracy was analyzed by both the conventional method (modular errors analysis) and the proposed method (angular errors analysis) by 3D graphics and numerical spherical statistics. Two packages in R programming language were performed to obtain graphics automatically. The results indicated that the proposed method is advantageous as it offers a more complete analysis of the positional accuracy, such as angular error component, uniformity of the vector distribution, error isotropy, and error, in addition the modular error component by linear statistics.
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http://dx.doi.org/10.3390/s101110128 | DOI Listing |
Front Med (Lausanne)
December 2024
The Department of Ophthalmology of the First Affiliated Hospital, Gannan Medical University, Ganzhou, Jiangxi, China.
Aim: To quantitatively analyze the relationship between spherical equivalent refraction (SER) and retinal vascular changes in school-age children with refractive error by applying fundus photography combined with artificial intelligence (AI) technology and explore the structural changes in retinal vasculature in these children.
Methods: We conducted a retrospective case-control study, collecting data on 113 cases involving 226 eyes of schoolchildren aged 6-12 years who attended outpatient clinics in our hospital between October 2021 and May 2022. Based on the refractive spherical equivalent refraction, we categorized the participants into four groups: 66 eyes in the low myopia group, 60 eyes in the intermediate myopia group, 50 eyes in the high myopia group, and 50 eyes in the control group.
J Appl Stat
July 2024
Department of Biostatistics and Data Science, School of Public Health, Houston, TX, USA.
The principle of independence is a fundamental yet often disregarded assumption in statistical inference. It is observed that the implications of correlations, if not considered, can lead to a conservative estimation of Type I error in the presence of positive linear correlations when utilizing the Kolmogorov-Smirnov (KS) test. Conversely, negative linear correlations may engender a liberal estimation of Type I error.
View Article and Find Full Text PDFHeliyon
January 2025
Transmission Electronic Microscopy Laboratory, Electronic Microscopy Unit, Department of Biology, University of Cauca, Popayán, 190002, Colombia.
A green methodology for the synthesis of carbon quantum dots (CQDs) from coffee husk without the use of any toxic solvents is proposed in this work. Sonochemical exfoliation of biochar, obtained from the thermal carbonization of coffee husk (from a certified coffee seeds) at low temperature in an air-restricted atmosphere, is described as an alternative procedure for the sustainable production of CQDs. The synthesized CQDs exhibited blue fluorescence with a strong maximum emission band at 410 nm when excited at a maximum absorption wavelength of 330 nm.
View Article and Find Full Text PDFJ Clin Med
December 2024
Faculty of Physics, University of Warsaw, Pasteura 5, 02-093 Warszawa, Poland.
: As Repeated Low-Level Red Light (RLRL) therapy is becoming increasingly prevalent in clinical practice, mainly in the Far East, largely due to its child-friendly nature and the feasibility of home use, this study aims to conduct a systematic review and meta-analysis to evaluate the efficacy of RLRL therapy in managing childhood myopia, specifically in relation to axial length (AL) and spherical equivalent refraction (SER), across a larger group of children aged from 6 to 16 years. : A systematic literature search was performed using PubMed, Scopus, and Web of Science to access relevant databases and to locate outcome studies. Eligibility criteria included publication type, participant characteristics, and outcomes report.
View Article and Find Full Text PDFDiagnostics (Basel)
January 2025
Nobel Eye Institute, Taipei 10041, Taiwan.
: To evaluate the effectiveness of astigmatism correction between topographic- and manifest-based methods in individuals who underwent second-generation keratorefractive lenticule extraction (KLEx) surgery. : This study was conducted with participants who underwent second-generation KLEx surgery. After exclusion, there were 46 and 43 participants in the manifest and topographic groups, respectively.
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