Results 261 to 270 of about 7,404 (306)

Noether's theory of mechanical systems with unilateral constraints

Applied Mathematics and Mechanics, 2000
In the last twenty years, the study of Noether's theory has become a popular topic by mechanicians, and a lot of remarkable generalizations have been made. However, all these researches were limited to systems with bilateral constraints, but, in practice, the problems with unilateral constraints are more interesting.
Zhang, Yi, Mei, Fengxiang
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POINTWISE BOUNDS FOR THE SOLUTION OF UNILATERAL CONSTRAINT PROBLEMS

The Quarterly Journal of Mechanics and Applied Mathematics, 1987
Upper and lower bounds to the solution at an interior point of a unilateral constraint problem for Laplace's equation in two dimensions are obtained and applied to the problem of a circular elastic membrane in contact with a rigid ellipsoid.
Collins, W. D., Harley, P. J., Sissaoui, H.   +2 more
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Buckling under unilateral constraints

International Journal of Solids and Structures, 1979
Abstract The classic variational theory for eigenvalue problems is extended so as to define the Euler critical load of a unilaterally constrained beam. The Euler load is obtained by minimising a Rayleigh quotient on a convex subset of a Hilbert space. The variational formulation also provides a method of bounding the buckling load by comparison.
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Multibody systems with unilateral constraints

Journal of Applied Mathematics and Mechanics, 2001
The author presents a brief survey of papers which incorporate the complementarity principle [see \textit{J. J. Moreau}, in Trends in applications of pure mathematics to mechanics. Vol. 2, 263--280 (1979; Zbl 0433.73096); \textit{P. D. Panagiotopoulos}, Hemivariantional inequalities. Applications in mechanics and engineering.
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Relaxation for a Class of Control Systems with Unilateral Constraints

Acta Applicandae Mathematicae, 2019
The paper is concerned with a nonlinear feedback control system of type \[ \left\{\begin{array}{ll}-x' \in A(x(t))+f(t,x(t))u(t)\\ x(0)=x_0, \quad u(t) \in U(t,x(t))\end{array}\right. \] in a time interval \(T=[0,b]\). Here, \(A:D(A)\subset \mathbb{R}^N \to 2^{\mathbb{R}^N}\) is a maximal monotone mapping and the control constraint multifunction \(U:T ...
Nikolaos S. Papageorgiou, Calogero Vetro, Francesca Vetro   +2 more
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Continuous control law from unilateral constraints

2008 IEEE International Conference on Robotics and Automation, 2008
The control approaches based on tasks, and particularly based on a hierarchy of tasks, enable to build complex behaviors with some nice properties of robustness and portability. However it is difficult to consider directly unilateral constraints in such a framework.
Nicolas Mansard, Oussama Khatib
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AN EXISTENCE RESULT FOR VIBRATIONS WITH UNILATERAL CONSTRAINTS

Mathematical Models and Methods in Applied Sciences, 2000
We are motivated by the study of dynamical systems with a finite number of degrees of freedom, subject to unilateral convex constraints without loss of energy at impacts. If we denote the set of constraints by K, the motion is described by [Formula: see text], where ψK is the indicatrix function of K.
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Control of a simple mechanism subject to unilateral constraints

42nd IEEE International Conference on Decision and Control (IEEE Cat. No.03CH37475), 2004
This paper studies statically admissible configurations for a mechanism standing on a horizontal plane (under the action of gravity) subject to mere inequality constraints, which do not inhibit its detachment from the plane and, possibly, its overturn. For a simple case, a strategy to design an admissible control law that drives the mechanism from one ...
GALEANI, SERGIO, MENINI, LAURA, TORNAMBE', ANTONIO   +2 more
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Context and Constraint in Presidential Unilateralism

SSRN Electronic Journal, 2011
How should we assess unilateral tactics and their contribution to presidential power in a less-than-unitary executive branch? To explore this question this paper examines the provenance of nearly 300 executive orders from 1947 through 1987. Archival data show that executive orders are frequently a less-than-perfect representation of presidential ...
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A Unified Approach to Integrate Unilateral Constraints in the Stack of Tasks

IEEE Transactions on Robotics, 2009
The control approaches based on the task function formalism, and particularly those structured as a prioritized hierarchy of tasks, enable complex behaviors with elegant properties of robustness and portability to be built. However, it is difficult to consider a straightforward integration of tasks described by unilateral constraints in such frameworks.
Mansard, Nicolas, Khatib, Oussama, Kheddar, Abderrahmane   +2 more
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