Seminars

Model discrimination parameter estimation and statistical inference require the formulation and efficient solution of nonlinear programming (NLP) problems. Frequently these problems are ill-posed due to over-parameterized models or data with incomplete information. These characteristics lead to failure of many popular NLP codes. This talk presents some basic parameter estimation methods that can also handle structured features of ill-posed parameter estimation problems. These are treated with composite step trust region methods.

We present a primal-dual interior point algorithm with a filter line search method for nonlinear programming. Local and global convergence properties of this method were analyzed in previous work. Here we provide a comprehensive description of the method including strategies for second order corrections filter restoration phase scaling and inertia correction of the KKT matrix. This method has been implemented in the IPOPT code which can be downloaded from http://www.coin-or.org. The code has been demonstrated on a broad variety of applications and engineering case studies.

Optimization formulations play a key part in many aspects of chemical process engineering. Moreover with the application of more accurate and complex process models a number of important algorithmic challenges must be addressed to deal with these optimization models efficiently. This talk presents an overview of problem classes in chemical process optimization and discusses key characteristics of these problems. In particular a hierarchy of optimization models is explored and typical problem formulations and solution strategies are presented at each level of this hierarchy.

Abstract Cells communicate with each other by sending and receiving signals that are transmitted across the cell membrane using a large number of proteins nucleotides and macromolecules. In this talk I will focus on two membrane-signaling protein systems and one RNA-mediated protein clustering system. The first protein Bin-Amphiphysin-Rvs (BAR) domain belongs to the class of "/curvature-sensing/" proteins which can cause dramatic deformations in cell membranes and is known to participate in processes such as cell fusion fission and endocytosis.

Abstract: This seminar will review recent work that has been carried out within the Polymer fluids Group developing a flexible plastic film that contains a multitude of microcapillaries. We call the material Microcapillary Film (MCF). The seminar will give the background to this unusual voided geometry and will discuss how the polymer melt extrusion process operates and how we are able to control capillary diameter in the range 0.5mm to 5 microns and how we control voidage in the range 10-70%.

The large surface area of nanoparticles can greatly increase the issolution rate of hydrophobic drugs. Moreover nanoscale carriers can inhibit the uptake of drug particles by the reticuloendothelial system during circulation permitting enough time for particles to localize in the leaky vasculature of tumors. We use impingement mixing and high supersaturating to create 100 nm particles via rapid precipitation. Particles are protected via block copolymers which co precipitate or are formed by fast coupling reaction during mixing.

Abstract: Energy integration motivated by the high cost and limited availability of energy is a key feature of modern process industries. Energy-integrated networks offer signicant cost ben- ets however are quite dicult to operate and control due to strong interactions among the individual units and network-level dynamics. Eectively controlling these integrated plants is a critical link to the economic viability and the energy and environmental sustainability of the chemical and energy supply chains.

Abstract: High performance computing (HPC) strategies can today be applied to petroleum-processing problems including those in the domain of heterogeneous catalysis. Advances in ab-initio quantum chemistry codes (i.e. Density Functional Theory) and the ability to parallelize calculations over hundreds of CPUs allow us to evaluate kinetics and thermochemistry for reaction networks of practical interest. The Minimum Energy Pathway can be elucidated and further calculations of vibrational-frequencies pre-exponential-factors and entropies can be combined into a detailed microkinetic model.

Abstract: In this talk I will present some of our recent work involving the adhesion of mosquitoes to surfaces. Specifically using AFM force measurements we are able to better understand the interactions between the hierarchical micro- and nanoscale structures on a mosquito foot and surfaces with different levels of roughness and wetting properties. We show that the origin of the surface adhesion is through van der Waals interactions however capillary forces can also contribute to the overall adhesion when the opposing surface is hydrophilic.

Recent emphasis on the release of greenhouse gases and the resulting potential for global warming has raised concerns over the emission of gases such as CO2. As the political and environmental demand increases efficient methods for the capture and sequestration of CO2 from the atmosphere will become increasingly important. The most likely options for separation and capture of CO2 from the flue gases of large combustion plants include chemical absorption physical and chemical adsorption and gas separation membranes.