Among other things, passive methods based on the processing of images of feature points or beacons captured by an image sensor are used to measure the relative position of objects. At least two cameras usually have to be used to obtain the required information, or the cameras are combined with other sensors working on different physical principles. This paper describes the principle of passively measuring three position coordinates of an optical beacon using a simultaneous method and presents the results of corresponding experimental tests. The beacon is represented by an artificial geometric structure, consisting of several semiconductor light sources. The sources are suitably arranged to allow, all from one camera, passive measurement of the distance, two position angles, the azimuth, and the beacon elevation. The mathematical model of this method consists of working equations containing measured coordinates, geometric parameters of the beacon, and geometric parameters of the beacon image captured by the camera. All the results of these experimental tests are presented.
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http://dx.doi.org/10.3390/s21155235 | DOI Listing |
J Affect Disord
January 2025
Center for Technology and Behavioral Health, Geisel School of Medicine, Dartmouth College, Lebanon, NH, United States; Department of Biomedical Data Science, Geisel School of Medicine, Dartmouth College, Lebanon, NH, United States; Quantitative Biomedical Sciences Program, Dartmouth College, Lebanon, NH, United States; Department of Psychiatry, Geisel School of Medicine, Dartmouth College, Lebanon, NH, United States.
Background: Major Depressive Disorder (MDD) is characterized by negative recall biases, which may impact how individuals with depressive symptoms report physical activity (PA), sedentary, and sleep behaviors. Additionally, there are discrepancies between subjective and objective behaviors in MDD. Thus, the current study investigated whether individuals with depressive symptoms differ in their subjective and objective PA, sedentary, and sleep behaviors, and whether the magnitude of these discrepancies differ from those in individuals without depressive symptoms.
View Article and Find Full Text PDFArch Phys Med Rehabil
January 2025
Exercise Intervention for Health Research Group (EXINH-RG), Department of Physiotherapy, University of Valencia, 46010 Valencia, Spain; National Research Centre for the Working Environment, Copenhagen, Denmark.
Objective: To examine the effects on strength, pain intensity, range of motion (ROM), and functionality of a 12-week dual-task resistance exercise program in patients undergoing rehabilitation from elbow fractures.
Design: Randomized Controlled Trial SETTING: Rehabilitation hospital.
Participants: Individuals undergoing elbow fracture rehabilitation.
PLoS One
January 2025
Department of Mechanical and Mechatronics Engineering, University of Waterloo, Waterloo, ON, Canada.
Lower-limb exoskeletons have demonstrated great potential for gait rehabilitation in individuals with motor impairments; however, maintaining human-exoskeleton coordination remains a challenge. The coordination problem, referred to as any mismatch or asynchrony between the user's intended trajectories and exoskeleton desired trajectories, leads to sub-optimal gait performance, particularly for individuals with residual motor ability. Here, we investigate the virtual energy regulator (VER)'s ability to generate coordinated locomotion in lower limb exoskeleton.
View Article and Find Full Text PDFLasers Med Sci
January 2025
Department of Endodontics, Faculty of Dentistry, Gülhane Faculty of Dentistry, University of Health Sciences, Ankara, Turkey.
Objective: This study aims to quantitatively compare the effects of standard needle irrigation (SNI), passive ultrasonic irrigation (PUI), EDDY, photon-initiated photoacoustic streaming (PIPS), and shock wave-enhanced emission photoacoustic streaming (SWEEPS) on the apical extrusion of irrigation solutions in teeth with severe canal curvature.
Materials And Methods: Seventy-five teeth with a single root and canal, and curvature angles ranging from 20° to 40°, were selected for this study. Root canal curvatures were measured from buccolingual and mesiodistal radiographs using ImageJ software (version 1.
Pediatr Radiol
January 2025
Department of Radiology, Children's Hospital of Philadelphia, 3401 Civic Center Blvd, Philadelphia, PA, 19104, USA.
Background: Splenic stiffness is a potential imaging marker of portal hypertension. Normative spleen stiffness values are needed to define diagnostic thresholds.
Objective: To report stiffness measurements of the spleen in healthy children undergoing liver magnetic resonance (MR) elastography across MRI vendors and field strengths.
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