scholarly journals More Reliable EEG Electrode Digitizing Methods Can Reduce Source Estimation Uncertainty, But Current Methods Already Accurately Identify Brodmann Areas

2019 ◽  
Author(s):  
Seyed Yahya Shirazi ◽  
Helen J. Huang
Keyword(s):  
Motion Capture ◽  
Structured Light ◽  
Reliability And Validity ◽  
Brodmann Area ◽  
3D Scanner ◽  
Estimation Uncertainty ◽  
Source Estimation ◽  
3D Scan ◽  
Brodmann Areas ◽  
Capture Method

AbstractElectroencephalography (EEG) and source estimation can be used to identify brain areas activated during a task, which could offer greater insight on cortical dynamics. Source estimation requires knowledge of the locations of the EEG electrodes. This could be provided with a template or obtained by digitizing the EEG electrode locations. Operator skill and inherent uncertainties of a digitizing system likely produce a range of digitization reliabilities, which could affect source estimation and the interpretation of the estimated source locations. Here, we compared the reliability of five digitizing methods (ultrasound, structured-light 3D scan, infrared 3D scan, motion capture probe, and motion capture) and determined the relationship between digitization reliability and source estimation uncertainty, assuming other contributors to source estimation uncertainty were constant. We digitized a mannequin head using each method five times and quantified the reliability and validity of each method. We created five hundred sets of electrode locations based on our reliability results and applied a dipole fitting algorithm (DIPFIT) to perform source estimation. The motion capture method, which recorded the locations of markers placed directly on the electrodes had the best reliability with an average electrode variability of 0.001cm. Then, in order of decreasing reliability were the method using a digitizing probe in the motion capture system, an infrared 3D scanner, a structured-light 3D scanner, and an ultrasound digitization system. Unsurprisingly, uncertainty of the estimated source locations increased with greater variability of EEG electrode locations and less reliable digitizing systems. If EEG electrode location variability was ~ 1 cm, a single source could shift by as much as 2 cm. To help translate these distances into practical terms, we quantified Brodmann area accuracy for each digitizing method and found that the average Brodmann area accuracy for all digitizing methods was > 80%. Using a template of electrode locations reduced the Brodmann area accuracy to ~ 50%. Overall, more reliable digitizing methods can reduce source estimation uncertainty, but the significance of the source estimation uncertainty depends on the desired spatial resolution. For accurate Brodmann area identification, any of the digitizing methods tested can be used confidently.

scholarly journals Structured-light 3D scanning of exhibited historical clothing—a first-ever methodical trial and its results

2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Jerzy Montusiewicz ◽  
Marek Miłosz ◽  
Jacek Kęsik ◽  
Kamil Żyła
Keyword(s):  
Cultural Heritage ◽  
Information Technologies ◽  
Structured Light ◽  
Three Dimensional ◽  
3D Models ◽  
3D Scanning ◽  
Dimensional Representation ◽  
3D Scanner ◽  
Three Dimensional Representation ◽  
3D Scanners

AbstractHistorical costumes are part of cultural heritage. Unlike architectural monuments, they are very fragile, which exacerbates the problems of their protection and popularisation. A big help in this can be the digitisation of their appearance, preferably using modern techniques of three-dimensional representation (3D). The article presents the results of the search for examples and methodologies of implementing 3D scanning of exhibited historical clothes as well as the attendant problems. From a review of scientific literature it turns out that so far practically no one in the world has made any methodical attempts at scanning historical clothes using structured-light 3D scanners (SLS) and developing an appropriate methodology. The vast majority of methods for creating 3D models of clothes used photogrammetry and 3D modelling software. Therefore, an innovative approach was proposed to the problem of creating 3D models of exhibited historical clothes through their digitalisation by means of a 3D scanner using structural light technology. A proposal for the methodology of this process and concrete examples of its implementation and results are presented. The problems related to the scanning of 3D historical clothes are also described, as well as a proposal how to solve them or minimise their impact. The implementation of the methodology is presented on the example of scanning elements of the Emir of Bukhara's costume (Uzbekistan) from the end of the nineteenth century, consisting of the gown, turban and shoes. Moreover, the way of using 3D models and information technologies to popularise cultural heritage in the space of digital resources is also discussed.

Measuring Leaf Areas with a Structured-Light 3D Scanner.

2014 ◽  
Vol 47 (3) ◽  
pp. 232-238
Author(s):  
Kyong-Hee Nam ◽  
◽  
Eun Mi Ko ◽  
Saeromi Mun ◽  
Chang-Gi Kim
Keyword(s):  
Structured Light ◽  
3D Scanner

Measurement of Pectoralis Minor Muscle Length in Women Diagnosed With Breast Cancer: Reliability, Validity, and Clinical Application

2020 ◽  
Vol 100 (3) ◽  
pp. 429-437
Author(s):  
Shana E Harrington ◽  
Julie Hoffman ◽  
Dimitrios Katsavelis
Keyword(s):  
Breast Cancer ◽  
Motion Capture ◽  
Reliability And Validity ◽  
Muscle Length ◽  
Motion Capture System ◽  
Unaffected Side ◽  
Pectoralis Minor ◽  
Affected Side ◽  
Pectoralis Minor Muscle ◽  
Minor Muscle

Abstract Background Decreased pectoralis minor muscle length is common after primary breast cancer treatment and can result in an abnormal position of the scapula. This position can contribute to shoulder pain and pathomechanics and can lead to problems such as impingement syndrome, rotator cuff tears, and frozen shoulder. Currently, there are limited reliable methods for measuring pectoralis minor length. Objective The objective of this study was to examine the reliability and validity of measuring pectoralis minor length in women diagnosed with breast cancer. Design This was a cross-sectional reliability and validity study. Methods Bilateral pectoralis minor length (in centimeters) was assessed using a palpation meter in women (N = 29) diagnosed with breast cancer by 2 licensed physical therapists who were masked to the measures. Bilateral pectoralis minor length was also measured using a motion capture system to assess validity. Results Intratester reliability (intraclass correlation coefficient, ICC [3,k] = 0.971; 95% confidence interval [CI] = 0.939–0.986; standard error of measurement [SEM] = 0.16 cm) and intertester reliability (ICC[3,k] = 0.915; 95% CI = 0.81–0.962; SEM = 0.31 cm) were excellent for the palpation meter on the affected side and the unaffected side (intratester reliability: ICC[3,k] = 0.951; 95% CI = 0.897–0.977; SEM = 0.19 cm; intertester reliability: ICC[3,k] = 0.945; 95% CI = 0.877–0.975; SEM = 0.22 cm). Significant correlations were found between the motion capture system and the palpation meter on the affected side (r = 0.87) and the unaffected side (r = 0.81). Bland-Altman plots between the palpation meter and the motion capture system demonstrated that all the measures fell within the limits of agreement. Limitations This study encountered possible errors with the accuracy of the motion capture system tracking because of the proximity of the markers and inherent volumetric restrictions. Conclusions The palpation meter is a reliable, valid, easily administered, and cost-effective tool for assessing pectoralis minor length in women with breast cancer.

scholarly journals Semi-Automating Low Back Compression Force Estimations with an Inertial Sensor

Proceedings ◽  
2020 ◽  
Vol 49 (1) ◽  
pp. 37
Author(s):  
Sam Gleadhill ◽  
Daniel James ◽  
Raymond Leadbetter ◽  
Tomohito Wada ◽  
Ryu Nagahara ◽  
...  
Keyword(s):  
Motion Capture ◽  
Injury Risk ◽  
Inertial Sensors ◽  
Inertial Sensor ◽  
Three Dimensional ◽  
Compressive Force ◽  
Low Back ◽  
Compression Force ◽  
Injury Risk Factor ◽  
Capture Method

There are currently no evidence-based practical automated injury risk factor estimation tools to monitor low back compressive force in ambulatory or sporting environments. For this purpose, inertial sensors may potentially replace laboratory-based systems with comparable results. The objective was to investigate inertial sensor validity to monitor low back compression force. Thirty participants completed a series of lifting tasks from the floor. Back compression force was estimated using a hand calculated method, an inertial sensor method and a three-dimensional motion capture method. Results demonstrated that semi-automation with a sensor had a higher agreement with motion capture compared to the hand calculated method, with angle errors of less than six degrees and back compression force errors of less than 200 Newtons. It was concluded that inertial sensors are valid to implement for static low back compression force estimations.

A robust automatic registration method for hand-held structured light 3D scanner

2014 ◽  
Author(s):  
Guomin Zhan ◽  
Mengqi Wu ◽  
Kai Zhong ◽  
Zhongwei Li ◽  
Yusheng Shi
Keyword(s):  
Structured Light ◽  
Automatic Registration ◽  
3D Scanner ◽  
Registration Method

scholarly journals The Reliability and Validity of a Clinical Assessment Tool to Measure Scapular Motion in All Three Anatomical Planes

2020 ◽  
Author(s):  
Oliver A Silverson ◽  
Nicole G Cascia ◽  
Carolyn M Hettrich ◽  
Nicholas R Heebner ◽  
Tim L Uhl
Keyword(s):  
Motion Capture ◽  
Reliability And Validity ◽  
Motion Capture System ◽  
Rater Reliability ◽  
Optical Motion ◽  
Arm Elevation ◽  
Clinical Measurements ◽  
Optical Motion Capture ◽  
Anatomical Plane ◽  
Scapular Motion

Abstract Context: A single clinical assessment device that objectively measures scapular motion in each anatomical plane is not currently available. The development of a novel electric goniometer affords the ability to quantify scapular motion in all three anatomical planes. Objective: Investigate the reliability and validity of an electric goniometer to measure scapular motion in each anatomical plane during arm elevation. Design: Cross-sectional. Setting: Laboratory setting. Patients or Other Participants: Sixty participants (29 females, 31 males) were recruited from the general population. Intervention(s): An electric goniometer was used to record clinical measurements of scapular position at rest and total arc of motion (excursion) during active arm elevation in two testing sessions separated by several days. Measurements were recorded independently by two examiners. In one session, scapular motion was recorded simultaneously with a 14-camera three-dimensional optical motion capture system. Main Outcome Measures: Reliability analysis included examination of clinical measurements for scapular position at rest and excursion during each condition. Both the intra-rater reliability between testing sessions and the inter-rater reliability recorded within the same session were assessed using Intraclass Correlation Coefficients (ICC2,3). The criterion-validity was examined by comparing the mean excursion values of each condition recorded by the electric goniometer to the 3D optical motion capture system. Validity was assessed by evaluating the average difference and root mean square error (RMSE). Results: The between session intra-rater reliability was moderate to good (ICC2,3: 0.628–0.874). The within session inter-rater reliability was moderate to excellent (ICC2,3: 0.545–0.912). The average difference between the electric goniometer and 3D optical motion capture system ranged from −7° to 4° and the RMSE was between 7–10°. Conclusions: The reliability of scapular measurements is best when a standard operating procedure is used. The electric goniometer provides an accurate measurement of scapular excursions in all three anatomical planes during arm elevation.

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