China
Africa
Explore chapters and articles related to this topic
Introduction to Systems of ODEs
Published in Vladimir A. Dobrushkin, Applied Differential Equations, 2022
Torque or moment is a measure of how much a force acting on an object causes that object to rotate. Suppose that a force F acts on a wrench pivoted on the axis through the origin. Then torque is defined as M=r×F⇒M=def|M|=rFsinϕ=Ftanr,
Introduction
Published in Vladimir A. Dobrushkin, Applied Differential Equations, 2018
Torque or moment is a measure of how much a force acting on an object causes that object to rotate. Suppose that a force F acts on a wrench pivoted on the axis through the origin. Then torque is defined as M=r×F⟹ M=def|M|=rFsinϕ=Ftanr,
Probability and Distribution Theory for Radar Detection
Published in Graham V. Weinberg, Radar Detection Theory of Sliding Window Processes, 2017
Moments of a random variable provide a measure of its central location, or average value in some senses, but extended in definition to continuous random variables. The mean of a continuous random variable X with density fX is defined to be E(X)=∫0∞tfX(t)dt, $$ E(X) = \mathop \smallint \limits_{0}^{\infty } tf_{X} (t)dt , $$
Feedback Control to a Static Target Angle in the Middle Finger Metacarpophalangeal Joint Using Functional Electrical Stimulation
Published in International Journal of Human–Computer Interaction, 2020
Kyosuke Watanabe, Makoto Oka, Hirohiko Mori
The moment arm is the shortest distance between the force across a joint and its center of rotation (Zajac, 1992). The moment arm of the flexor digitorum tendon has been shown to vary with the joint angle (An et al., 1983), and so, Hausdorff and Durfee (1991) controlled knee joint to the target joint angle by incorporating that the moment arm and the joint torque differ depending on the knee joint angle into the model. Therefore, it is assumed that the relationship between the electrical stimulation intensity and the joint angle change greatly changes depending on the state of the finger joint angle. Therefore, if a single control parameter is set regardless of the state of the finger joint angle, it is expected that the control accuracy will vary greatly depending on the joint angle.
A finite deformation, finite strain nonclassical internal polar continuum theory for solids
Published in Mechanics of Advanced Materials and Structures, 2019
K. S. Surana, A. D. Joy, J. N. Reddy
Using the equilibrium consideration for a single material particle encased in a volume element as a basis, Yang et al. [58] established the equilibrium of rotations for a system of material particles to account for the equilibrium of the moments of couples (or moments) of a body. When a system of forces are applied to a system of multiple particles the equilibrium relations are derived from a resultant force and a resultant couple of forces applied to an arbitrary point. The couple or moment of forces is a free vector in classical mechanics, which means that the effect of the couple applied on an arbitrary point in the space of the system of material particles is independent of the position of the point. In other words, the couple can translate to any point in the space freely and the resulting effects are unchanged. As a result, only the conventional force equilibrium and the moment equilibrium (balance of linear and angular momenta) are involved in the equilibrium relations [12], [65]–[67]. Equivalence of a couple resulting from the rotations that is not a free vector but a driving force that rotates the material particles requires considerations (see [58] for derivation) that eventually result into balance of moment of moments or couples for static equilibrium. This balance law is an extension of balance of angular momenta in classical mechanics to nonclassical mechanics in which moments due to rotations are independent quantities.