1,720,960 research outputs found
A Robust Hand Pose Estimation Algorithm for Hand Rehabilitation
No full textDuring a rehabilitation session, patient activity should be continuously monitored in order to correct wrong movements and to follow patient improvements. Therefore, the application of human motion tracking techniques to rehabilitation is finding more and more consensus. The aim of this paper is to propose a novel, low-cost method for hand pose estimation by using a monocular motion sensing device and a robust marker-based pose estimation approach based on the Unscented Kalman Filter. The hand kinematics is used to enclose geometrical constraints in the estimation process. The approach is applied for evaluating some significant kinematic parameters necessary for understanding human hand motor improvements during rehabilitation. In particular, the parameters evaluated for the hand fingers are joint positions, angles, Range Of Motion and trajectory. Moreover, the position, orientation and velocity of the wrist are estimated
Pose estimation algorithm for hand assessment
No full textPatient performance assessment should be as much as possible precise and independent from the examiner subjective judgment in order to evaluate therapy efficacy in restoring impaired sensori-motor functions. In this paper, a method for continuously monitoring patient activity in order to correct wrong movements and to follow patient improvements is proposed. In particular, a novel low-cost method for hand pose estimation by using a monocular motion sensing device and a robust marker-based pose estimation approach based on the Unscented Kalman Filter is presented. The hand kinematics is used to enclose geometrical constraints in the estimation process. The approach is applied for evaluating some significant kinematic parameters necessary to understand human hand motor improvements during rehabilitation. In particular, the estimated performance indicators are joint positions, angles, Range of Motion (RoM) and trajectory for the fingers and position, orientation and velocity for the wrist
Robust pose estimation algorithm for wrist motion tracking
No full textThe wrist plays a fundamental role in reaching and grasping actions, i.e. it guides the hand to the grasp position and adjusts its orientation on the basis of the grasping type and task. This paper proposes a novel, low-cost method for wrist pose estimation by using the Asus Xtion Pro Live motion sensing device and a robust marker-based tracking approach based on Unscented Kalman Filter (UKF). The hand palm kinematic model is also considered. The applicability of the approach to evaluate some interesting kinematics parameters, such as position, orientation, Range Of Motion, angular and linear velocity and trajectory has been proved. In particular, since the nature of the paper is to present a novel approach for wrist pose estimation, only initial validation for wrist kinematic measurement will be reported
Patient performance evaluation using Kinect and Monte Carlo-based finger tracking
Full text linkThe growing use of Virtual Reality (VR) in rehabilitation is justified by a number of advantages, such as an increase of patient motivation, repetitiveness of learning trials, possibility to tailor treatment to individual subject, safety of the environment, quantitative patient improvement assessment, and remote data access. This paper proposes a novel low-cost evaluation method of patient performance in task-oriented hand rehabilitation grounded on two key elements: a Virtual Environment (VE) which the patient has to interact with, and the Microsoft Kinect motion sensing device, which is used to fully interact with the VE and to feed back patient movements in order to perform an off-line analysis. To this purpose, the VE is equipped with a virtual hand and virtual objects the patient has to interact with. In order to make the interaction between patient and VE possible, a robust marker-based finger tracking algorithm has been developed by using Bayesian estimation methods.
In the proposed framework, the hand movements involved in daily activities are performed off-line by the therapist and are tracked by using the Kinect camera. The estimated hand joint trajectories are provided in input to a virtual hand model developed with the Matlab Virtual Reality Toolbox. The virtual hand reproduces the movements performed by the therapist and the patient is asked to imitate them. User motor improvements can be monitored by the Kinect camera, superimposing the therapist finger trajectories on the patient finger trajectories. The error between the two trajectories can be used for evaluating the patient residual mobility. The proposed system can be easily applied to home-based rehabilitation
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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