Optimization of truss-structures for finding optimal cross-sectional size, topology, and configuration of 2-D and 3-D trusses to achieve minimum weight is carried out using real-coded genetic algorithms (GAs). All the above three optimization techniques have been made possible by using a novel representation scheme. Although the proposed GA uses a fixed-length vector of design variables represe...

An e cient methodology is proposed to optimize space trusses considering geometric nonlinearity. The optimization task is performed by a continuous Particle Swarm Optimization (PSO). Design variables are cross sectional areas of the trusses and their weights are also taken as the objective function. Design constraints are de ned to restrict nodal displacements and element stresses and prevent t...

When we represent real-world systems as networks, the directions of links often convey valuable information. Finding module structures that respect link directions is one of the most important tasks for analysing directed networks. Although many notions of a directed module have been proposed, no consensus has been reached. This lack of consensus results partly because there might exist distinc...

Keywords--Design automation, Neural networks, minimum weight design, Lyapunov function, optimization, trusses

The transverse compression and shear collapse mechanisms of a second order, hierarchical corrugated truss structure have been analyzed. The two competing collapse modes of a first order corrugated truss are elastic buckling or plastic yielding of the truss members. In second order trusses, elastic buckling and yielding of the larger and smaller struts, shear buckling of the larger struts, and w...

We consider semidefinite programming (SDP) formulations of certain truss topology optimization problems, where a lower bound is imposed on the fundamental frequency of vibration of the truss structure. These SDP formulations were introduced in: [M. Ohsaki, K. Fujisawa, N. Katoh and Y. Kanno, Semi-definite programming for topology optimization of trusses under multiple eigenvalue constraints, Co...

This paper discusses evaluation techniques of the robustness function of trusses, which is regarded as one of measures of structural robustness, under the uncertainties of member stiffnesses and external forces. By using quadratic embedding of the uncertainty and the S-procedure, we formulate a quasiconvex optimization problem which provides lower bounds of the robustness functions. A bisection...

In this paper, we discuss evaluation techniques of the robustness function of trusses, which is regarded as one of measures of structural robustness, under the uncertainties of member stiffnesses and external forces. By using quadratic embedding of the uncertainty and the S-procedure, we formulate a quasiconvex optimization problem which provides the lower bounds of the robustness functions. A ...

A direct computational method is presented for the evaluation of the robustness function of linear elastic trusses associated with stress constraints. Under the uncertainties of external forces based on the info-gap model, the robustness function is formulated as the optimal objective value of an optimization problem with infinitely many constraint conditions. By using the strong duality theory...