Search results for "Torque"

Comparison of conventional hamstring/quadriceps ratio between genders in level-matched soccer players

2017

Abstract Objectives: The main goal of our study is to compare the hamstring/quadriceps (H/Q) ratio at different knee angles between level-matched male and female soccer players and to determine whether differences in the H/Q ratio exist between the dominant and the non-dominant leg. Methods: A cross-sectional study design was used to compare an isometric H/Q ratio and functional isokinetic ratio (between hamstring in eccentric contraction and quadriceps in concentric contraction) between males (n = 14) and females (n = 14). These ratios were studied at two different speeds of movement (60° s−1 and 180° s−1) and in five different positions (40°, 50°, 60°, 70° and 80° degrees of knee flexion)…

Hepatitis Due to Non-A-E Viruses

2011

On damping characteristics of frictional hysteresis in pre-sliding range

2016

Frictional hysteresis at relative motion in the pre-sliding range is considered. This effect is characterized by an elasto-plastic interaction, and that on the micro-scale, between two rubbing surfaces in contact that gives rise to nonlinear friction force. The pre-sliding friction force yields hysteresis in displacement. In this study, the damping characteristics of frictional hysteresis are analyzed. It is worth noting that we exclude the viscous damping mechanisms and focus on the pure hysteresis damping to be accounted in the friction modeling. The general properties of pre-sliding friction hysteresis are demonstrated and then compared with the limit case of discontinuous Coulomb fricti…

Time course of central and peripheral fatigue differs when maintaining a constant-EMG task vs. a constant-torque task

2005

Firefly optimization used to identify hysteresis parameter on rotational MR-damper

2014

In his paper the physical properties and mathematical models of a semi-active magnetorheological (MR) damper is studied. The considered models are the Dahl model and Bouc-Wen model. The parameters for these models are found by using a firefly optimization algorithm that minimizes the difference between experimental and simulated data. The objective of his paper is to compare different mathematical MR-damper models with the experimental data. The simulation results illustrate he effectiveness of he proposed optimization algorithm.

Skyrmion-number dependence of spin-transfer torque on magnetic bubbles

2015

We theoretically study the skyrmion-number dependence of spin-transfer torque acting on magnetic bubbles. The skymrion number of magnetic bubbles can take any integer value depending on the magnetic profile on its circumference and the size of the bubble. We find that the transverse motion of a bubble with respect to the charge current is greatly suppressed as the absolute value of the skyrmion number departs from unity, whereas the longitudinal motion is less sensitive.

Torque de desinserción y propiedades fisico-químicas de implantes dentales grabados con ácidos fluorhídrico y nítrico: Estudio experimental en perros

2006

Objetivo: Estudiar la composición, características superficiales y respuesta al torque de desinserción de una superficie implantaria tratada inicialmente con ácido fluorhídrico y posterior pasivado con ácidos fluorhídrico y nítrico. Diseño del estudio: En una primera fase, se seleccionaron 12 implantes en los que se estudiaron las características fisico-químicas mediante mediciones de energía dispersa de rayos X (EDS), microscopio electrónico de barrido y análisis de XPS (espectrometría de fotoelectrones). Asimismo, se colocaron 24 implantes -doce de 8 mm y doce de 10 mm de longitud-, en seis perros beagle, en los que tras un período de reposo, se procedió a la retirada de 12 implantes a la…

Method for estimating combined controller, joint and link stiffnesses of an industrial robot

2014

In this paper a new combined local/global approach for estimating the combined stiffnesses of joints in anthropomorphic robots is presented. The stiffness of each joint is a combination of several effects: i) stiffness of the links, ii) stiffness of joint bearings and gears and iii) stiffness of the position control loops given by the individual axis controller gains in the controller software. Experimental results are presented for an ABB IRB6600 industrial robot using measurements from a FARO Xi laser tracker and an ATI Omega160 force/torque sensor. The results show that there is a significant variation in stiffness among the individual joints of the robot and that the stiffnesses of the …

Relation between bone density and primary implant stability

2010

Aims: This study aims to relate bone density in Hounsfield units (Hu) with the primary implant stability measured by insertion torque (Ncm) and resonance frequency analysis (ISQ). Materials and Methods: Ten patients were included in this study. A total of 54 implant sites were provided from 10 computerized tomography scans. The computerized tomography scan was used for the preoperative evaluation of bone density for each patient. The bone mean density around planned implants was determined with Physioplanet TM software. Bone quality according resistance to drilling, insertion torque and resonance frequency measurements were recorded. Results: A statistically significant relationship was obs…

Design characteristics, primary stability and risk of fracture of orthodontic mini-implants: Pilot scan electron microscope and mechanical studies

2013

Objectives: Orthodontic mini-implants (OMIs) are increasingly used in orthodontics but can fail for various reasons. This study investigates the effects of OMI design characteristics on the mechanical properties in artificial bone. Material and Methods: Twelve self-drilling OMIs (2 small, 6 medium, 4 large) from 8 manufacturers were tested for their primary stability in simulated medium-high cancellous bone and the risk to fracture in high-density methacrylate blocks. For the assessments of the maximum insertion torque (IT) and torsional fracture (TF) 5 of each OMI were used and for the pull-out strength (POS) 10. The OMIs were inserted with a torque screwdriver (12 sec/360°) until the bott…