Search results for "kinematics"

On the dynamics of the AB Doradus system

2006

We present an astrometric analysis of the binary systems ABDorA /ABDorC and ABDorBa / ABDorBb. These two systems of well-known late-type stars are gravitationally associated and they constitute the quadruple ABDoradus system. From the astrometric data available at different wavelengths, we report: (i) a determination of the orbit of ABDorC, the very low mass companion to ABDorA, which confirms the mass estimate of 0.090Msun reported in previous works; (ii) a measurement of the parallax of ABDorBa, which unambiguously confirms the long-suspected physical association between this star and ABDorA; and (iii) evidence of orbital motion of ABDorBa around ABDorA, which places an upper bound of 0.4…

Evaluación de parámetros biomecánicos del lanzamiento de jabalina en lanzadores de diferente nivel de rendimiento

2000

Mediante análisis cinemático y utilizando como muestra a lanzadores agrupados en función de
 la marca conseguida (grupo internacional: atletas con marca superior a los 80 metros; y grupo
 nacional: atletas con marca inferior a 80 metros) el objetivo del estudio se centró en determinar si
 alguno de los parámetros utilizados para evaluar la eficacia del gesto establece diferencias entre
 uno y otro grupo de lanzadores.
 Los resultados muestran que algunos de dichos parámetros cinemáticos ayudan a establecer los
 márgenes para la pertenencia a los. Del total de las 41 variables contrastadas, sólo 8 de ellas
 establecían diferencias significativas entre grupo…

Validity and Reliability of the Leomo Motion-Tracking Device Based on Inertial Measurement Unit with an Optoelectronic Camera System for Cycling Peda…

2022

Background: The use of inertial measurement sensors (IMUs), in the search for a more ecological measure, is spreading among sports professionals with the aim of improving the sports performance of cyclists. The kinematic evaluation using the Leomo system (TYPE-R, Leomo, Boulder, CO, USA) has become popular. Purpose: The present study aimed to evaluate the reliability and validity of the Leomo system by measuring the angular kinematics of the lower extremities in the sagittal plane during pedaling at different intensities compared to a gold-standard motion capture camera system (OptiTrack, Natural Point, Inc., Corvallis, OR, USA). Methods: Twenty-four elite cyclists recruited from national a…

Mēchanismu kinēmatika

1938

Teōrētiskā mēchanika, 1. sējums: Kinemātika

1940

Punkta kinēmatika: lekcijas lasītas Latvijas Universitātes Inženierzinātņu fakultātē

1932

Fizika, 1. daļa [lekciju konspekts]

1941

Lasīts Medicinas fakultātes studentiem 1940/41. māc. g.

Cross-Talk Correction Method for Knee Kinematics in Gait Analysis Using Principal Component Analysis (PCA): A New Proposal

2014

International audience; Background: In 3D gait analysis, the knee joint is usually described by the Eulerian way. It consists in breaking down the motion between the articulating bones of the knee into three rotations around three axes: flexion/extension, abduction/adduction and internal/external rotation. However, the definition of these axes is prone to error, such as the "cross-talk'' effect, due to difficult positioning of anatomical landmarks. This paper proposes a correction method, principal component analysis (PCA), based on an objective kinematic criterion for standardization, in order to improve knee joint kinematic analysis. Methods: The method was applied to the 3D gait data of …

Prolonged exposure to microgravity modifies limb endpoint kinematics during the swing phase of human walking

2002

Many neurophysiological and behavioural studies suggested that the lower limb endpoint might be a centrally represented variable within the gravity reference frame and effectively controlled during the locomotion. This investigation examines the effects of prolonged exposure to microgravity upon lower limb endpoint kinematics. Seven cosmonauts were tested before and the 2nd day after a 6 month orbital mission. The spatio-temporal patterns of the limb extremity (malleolus) were analysed during the swing phase of the walk using a motion analysis system. Paths and velocity profiles of endpoint displacements were computed and compared for both the pre- and post-flight walking sessions. The resu…

Head movements in Finnish Sign Language on the basis of Motion Capture data

2015

This paper reports a study of the forms and functions of head movements produced in the dimension of depth in Finnish Sign Language (FinSL). Specifically, the paper describes and analyzes the phonetic forms and prosodic, grammatical, communicative, and textual functions of nods, head thrusts, nodding, and head pulls occurring in FinSL data consisting of a continuous dialogue recorded with motion capture technology. The analysis yields a novel classification of the kinematic characteristics and functional properties of the four types of head movement. However, it also reveals that there is no perfect correspondence between form and function in the head movements investigated.