Comparison of VHS video recording system with Apple Macintosh-based image analysis and modified CODA-3 systems in equine motion analysis

2002 ◽  
Vol 50 (2) ◽  
pp. 167-176 ◽  
Author(s):  
F. Szalay ◽  
W. Back ◽  
A. Barneveld ◽  
Keyword(s):  
Image Analysis ◽  
Motion Analysis ◽  
High Speed ◽  
Sampling Rate ◽  
Video Recording ◽  
Lateral View ◽  
Video Recordings ◽  
Artificial Illumination ◽  
Computer Based ◽  
Analysis System

A VHS video - computer-based image analysis combination is described as a low sampling rate motion analysis system. Video recordings were taken indoor without any artificial illumination at 25 fps sampling rate. The horse studied was running on a high-speed treadmill and observed at 1.6, 4 and 7 m/s velocities at walk, trot and canter, respectively. Left forelimb and hindlimb were recorded separately from lateral view. For comparison, parallel CODA-3 recordings were taken at the same time from the same position. Joint angles were expressed and compared in angle-time diagrams. Sampling of both systems has been synchronised by a timer device at ± 1/300 s error level. Results obtained with the two different recording systems were comparable in all joints measured with the exception of the fetlock. Inaccuracies in fetlock recordings are thought to be eliminated by measuring at controlled illumination. As a conclusion, the VHS-Macintosh setup appears to be promising as a simplified system for gait analysis.

scholarly journals The Relationship Between the Contact Force at the Ankle Hook and the Hamstring Muscle Force During the Nordic Hamstring Exercise

2021 ◽  
Vol 12 ◽  
Author(s):  
Mianfang Ruan ◽  
Li Li ◽  
Weiping Zhu ◽  
Tianchen Huang ◽  
Xie Wu
Keyword(s):  
United States ◽  
Motion Analysis ◽  
Contact Force ◽  
Sampling Rate ◽  
Contact Forces ◽  
Camera Motion ◽  
Hamstring Muscle ◽  
Novel Device ◽  
Moment Arms ◽  
Analysis System

A novel device has been developed to assess eccentric hamstring strength during the Nordic hamstring exercise (NHE) by measuring the contact force at the ankle hook (brace). The purpose of this study was to determine the correlation between the force measured at the ankle hook and the hamstring force estimated by a low extremity model. Thirteen male college sprinters were recruited to perform NHE on an instrumented device Nordbord (Vald Performance, Australia). Contact forces were measured at a sampling rate of 50 Hz at the hooks using the uniaxial load cells. 3D kinematics were measured simultaneously at a sampling rate of 200 Hz using a 16-camera motion analysis system (Vicon Motion Analysis, Oxford, United Kingdom) during the NHE. The data were processed with Visual 3D (C-Motion, Germantown, MD, United States) and OpenSim (NCSRR, Stanford, CA, United States) to calculate the knee joint center’s coordinates and hamstring moment arms during NHE. A static low extremity model was built to estimate the hamstring force during NHE. We have observed a significant but not very high correlation (r2 = 0.58) between peak hamstring force and the peak contact force at the ankle hook. The peak contact force measured at the ankle hook can only explain a little more than half of the variations in peak hamstring muscle forces during NHE. Caution must be exercised when assessing the eccentric hamstring strength using the ankle contact force during NHE.

Abstract 115: Video Review and Time-Motion Analysis of the Causes of No-Flow Intervals as Recorded by Accelerometer During Cardiopulmonary Resuscitation

Circulation ◽  
2014 ◽  
Vol 130 (suppl_2) ◽  
Author(s):  
Yi-Chia Lee ◽  
Huang-Fu Yeh ◽  
Yen-Pin Chen ◽  
Chun-Yi Chang ◽  
Wei-Ting Chen ◽  
...  
Keyword(s):  
Cardiopulmonary Resuscitation ◽  
Motion Analysis ◽  
Video Recording ◽  
Electric Activity ◽  
Flow Duration ◽  
Video Review ◽  
Video Recordings ◽  
Time Motion ◽  
Comprehensive Information

Objectives: Accelerometer (Q-CPR) has been developed and promoted to monitor the quality of cardiopulmonary resuscitation (CPR). Although the device registers the occurrence of no-flow intervals, it does not provide comprehensive information on the causes leading to these no-flow intervals. This study is aimed to analyze causes leading to CPR interruptions registered by Q-CPR by reviewing corresponding video recordings of the resuscitation sessions. Methods: Accelerometer recordings (Q-CPR, Philips) of 20 CPR episodes from December 2010 to April 2014 in a tertiary university ED were obtained. Frequency, timing, duration, and types of no-flow intervals, defined as no-flow duration >= 1.5 seconds, were reviewed. Video recordings of the corresponding CPR sessions were reviewed. Causes leading no flow intervals registered by Q-CPR were categorized and analyzed. Results: The duration of CPR reviewed for the cases averaged 8.59 minutes (range 2.23 - 19.04 minutes). No-flow intervals (pauses >= 1.5 seconds) occurred 122 times (averaged one interruption every 1.27 minutes of CPR) with an average no-flow intervals of 6.45 seconds (range 1.54 - 51.50 seconds). Through detail review of the video-recordings corresponding to the no-flow intervals registered by Q-CPR, the leading causes of no-flow intervals are associated with pulse checks for pulseless electric activity- PEA (19.5%), pre-shock pauses (13.9%), ultrasound exam (11.6%) and intubation (9.6%), as displayed in the following chart. Conclusion: Video recording and time-motion analysis provide detailed information on the causes leading to no-flow intervals registered by QCPR, and could complement information acquired by Q-CPR. Measures should be taken to address leading causes of CPR interruption, especially pulse checks for PEA and pre-shock pauses, to promote quality of CPR.

Validation of High Speed Motion Analysis System to Measure Maximal Speed

2010 ◽  
Vol 42 ◽  
pp. 686
Author(s):  
Nidhi Gupta ◽  
Govindasamy Balasekaran ◽  
Visvasuresh Victor Govindaswamy
Keyword(s):  
Motion Analysis ◽  
High Speed ◽  
Motion Analysis System ◽  
Maximal Speed ◽  
Analysis System

Differences Among an Expert and a Non Expert in the Behavior for Chucking in the Lathe

2013 ◽  
Author(s):  
Porakoch Sirisuwan ◽  
Tetsushi Koshino ◽  
Chieko Narita ◽  
Takashi Yoshikawa
Keyword(s):  
Motion Analysis ◽  
Sampling Rate ◽  
Arm Movement ◽  
Motion Analysis System ◽  
Video Cameras ◽  
Position Data ◽  
Lathe Machine ◽  
The Difference ◽  
Infrared Cameras ◽  
Analysis System

The expert worker (85 years old) has worked for 70 years and the non expert (16 years old) has worked 1 year of experience for the lathe processing. The subjects were compared the difference in the waist, the shoulder and the fore arm movement between the two worker while they were chucking on the lathe machine. Determination used the same parts and the same type of lathe machine for investigated. There were 4 main categories that related three stances position alignment and two hands position on the key chuck. Using the 6 infrared cameras and 2 video cameras captured the position of each marker. All markers position data which synchronization was taken by a motion analysis system (sampling rate: 100Hz). As a results show the balance movement both the waist and the shoulder during the chucking that had significantly greater in the expert worker than the non expert worker.

A Computer‐based image analysis system for biocide screening

Biofouling ◽  
1996 ◽  
Vol 10 (1-3) ◽  
pp. 225-237 ◽  
Author(s):  
B Wigglesworth‐Cooksey ◽  
K E Cooksey
Keyword(s):  
Image Analysis ◽  
Image Analysis System ◽  
Computer Based ◽  
Analysis System

scholarly journals Chest CT Images for COVID-19: Radiologists and Computer-based detection

2020 ◽  
Author(s):  
Qingli Dou ◽  
Jiangping Liu ◽  
Wenwu Zhang ◽  
Yanan Gu ◽  
Wan-Ting Hsu ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Image Analysis ◽  
Ct Images ◽  
Chest Ct ◽  
Image Analysis System ◽  
Ct Image ◽  
Chest Computed Tomography ◽  
Computer Based ◽  
Analysis System ◽  
Novel Coronavirus

ABSTRACTBackgroundCharacteristic chest computed tomography (CT) manifestation of 2019 novel coronavirus (COVID-19) was added as a diagnostic criterion in the Chinese National COVID-19 management guideline. Whether the characteristic findings of Chest CT could differentiate confirmed COVID-19 cases from other positive nucleic acid test (NAT)-negative patients has not been rigorously evaluated.PurposeWe aim to test whether chest computed tomography (CT) manifestation of 2019 novel coronavirus (COVID-19) can be differentiated by a radiologist or a computer-based CT image analysis system.MethodsWe conducted a retrospective case-control study that included 52 laboratory-confirmed COVID-19 patients and 80 non-COVID-19 viral pneumonia patients between 20 December, 2019 and 10 February, 2020. The chest CT images were evaluated by radiologists in a double blind fashion. A computer-based image analysis system (uAI system, Lianying Inc., Shanghai, China) detected the lesions in 18 lung segments defined by Boyden classification system and calculated the infected volume in each segment. The number and volume of lesions detected by radiologist and computer system was compared with Chi-square test or Mann-Whitney U test as appropriate.ResultsThe main CT manifestations of COVID-19 were multi-lobar/segmental peripheral ground-glass opacities and patchy air space infiltrates. The case and control groups were similar in demographics, comorbidity, and clinical manifestations. There was no significant difference in eight radiologist identified CT image features between the two groups of patients. There was also no difference in the absolute and relative volume of infected regions in each lung segment.ConclusionsWe documented the non-differentiating nature of initial chest CT image between COVID-19 and other viral pneumonia with suspected symptoms. Our results do not support CT findings replacing microbiological diagnosis as a critical criterion for COVID-19 diagnosis. Our findings may prompt re-evaluation of isolated patients without laboratory confirmation.

Use of sonomicrometry demonstrates the link between prey capture kinematics and suction pressure in largemouth bass

2002 ◽  
Vol 205 (22) ◽  
pp. 3445-3457 ◽  
Author(s):  
Christopher P. J. Sanford ◽  
Peter C. Wainwright
Keyword(s):  
Largemouth Bass ◽  
High Speed ◽  
Prey Capture ◽  
Buccal Cavity ◽  
Micropterus Salmoides ◽  
Sampling Rate ◽  
Great Promise ◽  
Suction Pressure ◽  
Video Recordings ◽  
Explosive Expansion

SUMMARYSuction feeding in fishes is the result of a highly coordinated explosive expansion of the buccal cavity that results in a rapid drop in pressure. Prey are drawn into the mouth by a flow of water that is generated by this expansion. At a gross level it is clear that the expansion of the buccal cavity is responsible for the drop in pressure. However, attempts using high-speed video recordings to demonstrate a tight link between prey capture kinematics and suction pressure have met with limited success. In a study with largemouth bass Micropterus salmoides, we adopted a new technique for studying kinematics, sonomicrometry, to transduce the movement of skeletal elements of the head during feeding, and synchronized pressure recordings at a sampling rate of 500 Hz. From the positional relationships of six piezoelectric crystals we monitored the internal movements of the buccal cavity and mouth in both mid-sagittal and transverse planes. We found that peak subambient pressure was reached very early in the kinematic expansion of the buccal cavity, occurring at the time when the rate of percentage change in buccal volume was at its peak. Using multiple regression analyses we were consistently able to account for over 90%, and in the best model 99%, of the variation in buccal pressure among strikes using kinematic variables. Sonomicrometry shows great promise as a method for documenting movements of biological structures that are not clearly visible in the external view provided by film and video recordings.

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