the nonlinear static procedures (nsps) proposed by design codes do not lead to reliable results especially for tall buildings. they generally provide inconsistent estimates of inelastic seismic demands, especially for the top floors due to their inabilities in considering the higher modes effects. in this paper, a new enhanced pushover procedure is proposed which is based on the envelope of the...

We present a simple mathematical model giving a possible description of a partially coherent light beam exhibiting a flat-topped transverse intensity profile. Such a model allows us to deduce the modal distribution inside a multimode stable optical cavity, assuming that the modes are of the Hermite-Gauss type. The analytical expression used to represent flat-topped profiles is of the flattened ...

A procedure for the optimal modal design of a beam made of a composite material was developed. The two components considered for the composite are a light concrete as the matrix and a polyester fiber as the filler. The fibers inside of the matrix tend to aggregate and to take this into account in the modeling, a subroutine that generates random finite elements corresponding to the fiber cluster...

When a cantilever beam rotates about an axis perpendicular to its neutral axis, its modal characteristics often vary significantly. If the geometric shape and the material property of the beam are given, the modal characteristic variations can be accurately estimated following a well-established analysis procedure employing assumed mode method or finite element method. In many practical design ...

The damage identification study presented in this article leveraged a full-scale sub-component experiment conducted in the Charles Lee P owell Structural Research Laboratories at the University of California, San Diego. As a payload project attached to a quasi-static test of a full-scale composite beam, a high-quality set of lowamplitude vibration response data was acquired from the beam at var...

A new solution for the acoustic field produced by a point source in a wedge-shaped ocean channel with pressure-release boundaries is presented. The solution is in the form of a sum of normal modes, which reduces in the immediate vicinity of the source point to the free-field solution for a point source. The radiation field associated with each mode forms a well-defined beam which diverges as th...

Modal analysis of an optical beam refers to analyzing the beam into its constituent modes. In this paper, a new compressive approach for modal analysis of sparse beams using generalized interferometry in arbitrary degrees of freedom (DoFs) is proposed. It is shown that the modal content can be recovered by solving a sparse recovery problem based on random interferometric measurements obtained b...

In this paper, the dynamic response of an axially moving viscoelastic beam with simple supports is calculated analytically based on Timoshenko theory. The beam material property is separated to shear and bulk effects. It is assumed that the beam is incompressible in bulk and viscoelastic in shear, which obeys the standard linear model with the material time derivative. The axial speed is charac...

This thesis is devoted to the study of transverse modes in large-mode-area (LMA) fibers. It highlights the importance of transverse spatial-hole burning (TSHB) effect in LMA multimode fibers through experiments and simulations. The measured beam-quality factor decreases until the gain becomes saturated in an amplified spontaneous emission (ASE) source based on an Yb-doped LMA multimode fiber. A...