Studies have shown that significant vehicle mass and cost savings are possible with the use of ballutes for aero-capture. Through NASA’s In-Space Propulsion program, a preliminary examination of ballute sensitivity to geometry and Reynolds number was conducted, and a single-pass coupling between an aero code and a finite element solver was used to assess the static aeroelastic effects. There re...

This paper presents simple analytical approaches for evaluating progressive collapse potential of lowand mid-rise buildings that could be used in routine design by design professionals. Although nonlinear time history analysis would be more realistic in representing progressive collapse phenomenon, high fidelity structural models to represent nonlinear structural behavior are required to produc...

A meshfree method for nonlinear analysis of two-dimensional reinforced concrete structures subjected to monotonic static loading is presented. The concrete model is implemented in the context of the smeared rotating crack approach. The stress-strain relationship for steel bars accounts for the surrounding concrete bonded to the bar (tension stiffening effect). The principle of virtual work (var...

The work presented herein sets out to investigate numerically, by means of nonlinear finite element analysis, the effect of un-reinforced concrete or masonry infill walls on the overall structural response of reinforced concrete frames under static monotonic and seismic loading. For this purpose, a nonlinear finite element package purpose built for the analysis of concrete structures is employe...

This paper presents a time domain analysis framework for predicting nonlinear response of long-span bridges under turbulent winds. The nonlinear unsteady aerodynamic forces are modeled based on static force coefficients, flutter derivatives, admittance functions, and their spanwise correlations at varying angles of incidence. This analysis framework incorporates frequency dependent parameters o...

electric arc furnace (eaf) is one of the largest loads in electric power systems. it is highly time varying and nonlinear. its reactive power variations cause voltage fluctuations in nearby system which is known as flicker. on the other hand the nonlinear voltage-current characteristic causes strong voltage and current harmonics in eaf. to this end flexible ac transmission systems (facts) techn...

The particle filter (PF) has emerged as a powerful tool for solving nonlinear and/or non-Gaussian filtering problems. When some of the states enter the model linearly, this can be exploited by using particles only for the “nonlinear” states and employing conditional Kalman filters for the “linear” states; this leads to the Rao-Blackwellised particle filter (RBPF). However, it is well known that...

Automatic verification by means of extended static checking (ESC) has seen some success in industry and academia due to its lightweight and easy-to-use nature. Unfortunately, ESC comes at a cost: a host of logical and practical completeness and soundness issues. Interactive verification technology, on the other hand, is usually complete and sound, but requires a large amount of mathematical and...

In this paper, static indentation and low velocity impact responses of a fully backed composite sandwich plate subjected to a rigid flat-ended cylindrical indenter/impactor are analytically investigated. The analysis is nonlinear due to nonlinear strain-displacement relation. In contrast to the existed analytical models for the indentation of composite sandwich plates, the stacking sequence of ...

Response modification factor (R-factor) is one of the seismic design parameters to consider nonlinear performance of building structures during strong earthquake. Relying on this, many seismic design codes led to reduce earthquake loads imposed to the structure. The present paper tries to evaluate the R-factors of conventional concentric braced frames (CBFs) and special moment frames (MRFs) in ...