Stochastic, iterative search methods such as Evolutionary Algorithms (EAs) are proven to be efficient optimizers. However, they require evaluation of the candidate solutions which may be prohibitively expensive in many real world optimization problems. Use of approximate models or surrogates is being explored as a way to reduce the number of such evaluations. In this paper we investigated three...

Deformable joint contact models can be used to estimate loading conditions for cartilage-cartilage, implant-implant, human-orthotic, and foot-ground interactions. However, contact evaluations are often so expensive computationally that they can be prohibitive for simulations or optimizations requiring thousands or even millions of contact evaluations. To overcome this limitation, we developed a...

In surrogate pregnancies genetic parents have little opportunity for early bonding with their infants either prenatally (in utero) or during the immediate postnatal period. Procedures commonly used to induce lactation include both pharmacologic and nonpharmacologic methods often in combination. Studies reporting induced lactation are sparse due to the rarity of augmented lactation. Here we repo...

The effectiveness of surrogate based optimization of helicopter rotor blades for vibration reduction using kriging global approximations is investigated. The search for the optimal design is conducted using two methods: (1) the “one-shot” approach in which the surrogate is optimized directly and (2) a method based on the expected improvement function which seeks to find optimal designs while re...

In the present paper an adaptive Kriging surrogate model with active refinement is proposed to solve component reliability analysis problems (i.e. with a single design point) with a reasonable limit for the dimensionality of the basic random variables space. The model uses an adaptive Kriging-based trust region method to search for the design point and predict the failure probability based on t...

We propose a new majorization-minimization (MM) method for non-smooth and non-convex programs, which is general enough to include the existing MM methods. Besides the local majorization condition, we only require that the difference between the directional derivatives of the objective function and its surrogate function vanishes when the number of iterations approaches infinity, which is a very...

In mechanical and structural systems, resonance may cause large strains and stresses which can lead to the failure of the system. Since it is often not possible to change the frequency content of the external load excitation, the phenomenon can only be avoided by updating the design of the structure. In this paper, a design optimization strategy based on the integration of the Component Mode Sy...

Metamodeling has been widely used for design optimization by building surrogate models for computationally intensive engineering application problems. Among all the metamodeling methods, the kriging method has gained significant interest for its accuracy.However, in traditional krigingmethods, themean structure is constructed using a fixed set of polynomial basis functions, and the optimization...

For the design and optimization of multistage assembly processes, a computationally cheap mathematical model that links design parameters with the final product dimensional quality is highly desirable. We propose a systematic approach to building a surrogate model of simulations of multistage assembly processes. At the heart of this approach is a multiple-input-multiple-output surrogate modelin...

Title of Document: MULTIVARIATE STATISTICAL TECHNIQUES FOR ACCURATELY AND NONINVASIVELY LOCALIZING TUMORS SUBJECT TO RESPIRATIONINDUCED MOTION Kathleen T. Malinowski, Doctor of Philosophy, 2012 Directed By: Warren D. D’Souza, Associate Professor, Fischell Department of Bioengineering and Director, Department of Medical Physics Tumors in the lung, liver, and pancreas can move considerably with n...