ar X iv : m at h / 99 06 04 3 v 3 [ m at h . R A ] 2 7 Ju l 1 99 9 GENERALIZED SELECTIVE MODAL ANALYSIS

ar X iv : m at h / 99 06 04 3 v 2 [ m at h . R A ] 1 8 Ju n 19 99 GENERALIZED SELECTIVE MODAL ANALYSIS

1. Review of SMA. Selective Modal Analysis (SMA) is a physically motivated framework for understanding, simplifying and analyzing complex linear time invariant models of dynamic systems. SMA can focus on selected portions of the structure and behaviour of the system [1, 2]. In many physical systems, it can be readily recognized that some set of modes is asociated to a certain set of variables. ...

ar X iv : m at h / 99 07 08 5 v 1 [ m at h . G R ] 1 3 Ju l 1 99 9 LOOPS AND SEMIDIRECT PRODUCTS

ar X iv : m at h / 99 06 19 7 v 1 [ m at h . G T ] 2 8 Ju n 19 99 The size of spanning disks for polygonal knots .

For each integer n ≥ 1 we construct a closed unknotted Piecewise Linear curve Kn in R 3 having less than 11n edges with the property that any Piecewise Linear triangluated disk spanning the curve contains at least 2 triangles.

ar X iv : m at h / 99 07 13 7 v 1 [ m at h . L O ] 2 2 Ju l 1 99 9 STRONGLY MEAGER AND STRONG MEASURE ZERO SETS

In this paper we present two consistency results concerning the existence of large strong measure zero and strongly meager sets.

ar X iv : m at h / 99 07 18 5 v 1 [ m at h . M G ] 2 9 Ju l 1 99 9 Higher dimensional flexible polyhedra ∗

It is show that sphere homeomorphic flexible polyhedra (with self intersections) do really exist in n-dimensional Euclidean, Lobachevskij and spherical spaces for each n ≥ 3. 1991 Mathematics Subject Classification: 52C25, 52B11.