# Some uniqueness and observability problems arising in the control of vibrations

Journées équations aux dérivées partielles (1999)

- page 1-8
- ISSN: 0752-0360

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topZuazua, Enrique. "Some uniqueness and observability problems arising in the control of vibrations." Journées équations aux dérivées partielles (1999): 1-8. <http://eudml.org/doc/93376>.

@article{Zuazua1999,

abstract = {We discuss a control problem for the Lamé system which naturally leads to the following uniqueness problem: Given a bounded domain of $\mathbf \{R\}^3$, are there non-trivial solutions of the evolution Lamé system with homogeneous Dirichlet boundary conditions for which the first two components vanish? We show that such solutions do not exist when the domain is Lipschitz. However, in two space dimensions one can build easily polygonal domains in which there are eigenvibrations with the first component being identically zero. These uniqueness problems do not feet in the context of the classical Cauchy problem. They are of global nature and, therefore, the geometry of the domain under consideration plays a key role. We also present a list of related open problems.},

author = {Zuazua, Enrique},

journal = {Journées équations aux dérivées partielles},

keywords = {observability; 1-D wave equation; rapidly oscillating coefficients; finite-difference approximations; microstructure; heterogeneous medium; high frequencies},

language = {eng},

pages = {1-8},

publisher = {Université de Nantes},

title = {Some uniqueness and observability problems arising in the control of vibrations},

url = {http://eudml.org/doc/93376},

year = {1999},

}

TY - JOUR

AU - Zuazua, Enrique

TI - Some uniqueness and observability problems arising in the control of vibrations

JO - Journées équations aux dérivées partielles

PY - 1999

PB - Université de Nantes

SP - 1

EP - 8

AB - We discuss a control problem for the Lamé system which naturally leads to the following uniqueness problem: Given a bounded domain of $\mathbf {R}^3$, are there non-trivial solutions of the evolution Lamé system with homogeneous Dirichlet boundary conditions for which the first two components vanish? We show that such solutions do not exist when the domain is Lipschitz. However, in two space dimensions one can build easily polygonal domains in which there are eigenvibrations with the first component being identically zero. These uniqueness problems do not feet in the context of the classical Cauchy problem. They are of global nature and, therefore, the geometry of the domain under consideration plays a key role. We also present a list of related open problems.

LA - eng

KW - observability; 1-D wave equation; rapidly oscillating coefficients; finite-difference approximations; microstructure; heterogeneous medium; high frequencies

UR - http://eudml.org/doc/93376

ER -

## References

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