Matching Items (3)

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Comparison of Cervical Motion Restriction and Interface Pressure Between Two Cervical Collars

Description

The objective of this study was to compare the effectiveness of a newly developed DJO Global cervical collar with the previously studied Össur Americas Miami J collar in restricting cervical

The objective of this study was to compare the effectiveness of a newly developed DJO Global cervical collar with the previously studied Össur Americas Miami J collar in restricting cervical spine movement and reducing tissue interface pressure. 3D kinematic data were obtained for twelve healthy participants volunteers (6 female, 6 male) using a 10 camera infrared motion capture system (Motion Analysis Corp.). Cervical range of motion (CROM) in each plane was calculated as the angle between the head and thorax rigid-body axes. CROM was calculated using custom-written Matlab (MathWorks, Natick, MA) scripts. Tissue interface pressure (TIP) was measured between the head and the collar with three flexible pressure sensor pads over the anterior mandibles and occiput. The distribution of interface pressures was obtained in both the seated and supine positions. Both collars significantly restricted range of motion in all movement directions (p < 0.001) compared to no collar. There were no statistically significant differences in restrictiveness nor tissue interface pressures between the collars. Both collars exhibited similar CROM restriction in all planes and similar interface pressures in both positions. The newly developed DJO collar properly functioned as it markedly restricted spinal movement and produced low contact pressures. The Miami J collar has long been scientifically recognized as an effective collar; however, our data shows that the latest DJO collar was able to exhibit comparable contact pressures and decreases in cervical motion. As manufacturers produce improved collar designs, continued scientific testing should be executed in search of a collar capable of enhanced CROM restriction and the diminution of TIP.

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Date Created
  • 2020-05

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Upper body motion analysis using kinect for stroke rehabilitation at the home

Description

Motion capture using cost-effective sensing technology is challenging and the huge success of Microsoft Kinect has been attracting researchers to uncover the potential of using this technology into computer vision

Motion capture using cost-effective sensing technology is challenging and the huge success of Microsoft Kinect has been attracting researchers to uncover the potential of using this technology into computer vision applications. In this thesis, an upper-body motion analysis in a home-based system for stroke rehabilitation using novel RGB-D camera - Kinect is presented. We address this problem by first conducting a systematic analysis of the usability of Kinect for motion analysis in stroke rehabilitation. Then a hybrid upper body tracking approach is proposed which combines off-the-shelf skeleton tracking with a novel depth-fused mean shift tracking method. We proposed several kinematic features reliably extracted from the proposed inexpensive and portable motion capture system and classifiers that correlate torso movement to clinical measures of unimpaired and impaired. Experiment results show that the proposed sensing and analysis works reliably on measuring torso movement quality and is promising for end-point tracking. The system is currently being deployed for large-scale evaluations.

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Created

Date Created
  • 2012

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Semantic sparse learning in images and videos

Description

Many learning models have been proposed for various tasks in visual computing. Popular examples include hidden Markov models and support vector machines. Recently, sparse-representation-based learning methods have attracted a lot

Many learning models have been proposed for various tasks in visual computing. Popular examples include hidden Markov models and support vector machines. Recently, sparse-representation-based learning methods have attracted a lot of attention in the computer vision field, largely because of their impressive performance in many applications. In the literature, many of such sparse learning methods focus on designing or application of some learning techniques for certain feature space without much explicit consideration on possible interaction between the underlying semantics of the visual data and the employed learning technique. Rich semantic information in most visual data, if properly incorporated into algorithm design, should help achieving improved performance while delivering intuitive interpretation of the algorithmic outcomes. My study addresses the problem of how to explicitly consider the semantic information of the visual data in the sparse learning algorithms. In this work, we identify four problems which are of great importance and broad interest to the community. Specifically, a novel approach is proposed to incorporate label information to learn a dictionary which is not only reconstructive but also discriminative; considering the formation process of face images, a novel image decomposition approach for an ensemble of correlated images is proposed, where a subspace is built from the decomposition and applied to face recognition; based on the observation that, the foreground (or salient) objects are sparse in input domain and the background is sparse in frequency domain, a novel and efficient spatio-temporal saliency detection algorithm is proposed to identify the salient regions in video; and a novel hidden Markov model learning approach is proposed by utilizing a sparse set of pairwise comparisons among the data, which is easier to obtain and more meaningful, consistent than tradition labels, in many scenarios, e.g., evaluating motion skills in surgical simulations. In those four problems, different types of semantic information are modeled and incorporated in designing sparse learning algorithms for the corresponding visual computing tasks. Several real world applications are selected to demonstrate the effectiveness of the proposed methods, including, face recognition, spatio-temporal saliency detection, abnormality detection, spatio-temporal interest point detection, motion analysis and emotion recognition. In those applications, data of different modalities are involved, ranging from audio signal, image to video. Experiments on large scale real world data with comparisons to state-of-art methods confirm the proposed approaches deliver salient advantages, showing adding those semantic information dramatically improve the performances of the general sparse learning methods.

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Created

Date Created
  • 2014