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Displaying 301 - 325 of 446

The DEMO Quasisymmetric Stellarator

February 26, 2010
Author(s)
Paul R. Garabedian, Geoffrey B. McFadden
The NSTAB code solves differential equations in conservation form, and the TRAN test particle code tracks guiding center orbits in a fixed background, to provide simulations of equilibrium, stability, and transport in tokamaks and stellarators. These codes

Predicted Functions of MdmX in Fine Tuning the Response of p53 to DNA Damage

February 5, 2010
Author(s)
Sohyoung Kim, Mirit I. Aladjem, Geoffrey B. McFadden, Kurt W. Kohn
Tumor suppressor protein p53 is negatively regulated by two structurally homologous proteins, Mdm2 and MdmX. In contrast to Mdm2, MdmX lacks ubiquitin ligase activity. Although the essential interactions of MdmX are known, it is not clear how they function

Measuring the Utility/Path Diversity Tradeoff in Multipath Protocols

October 20, 2009
Author(s)
Fern Y. Hunt, Vladimir V. Marbukh
We derive a model of congestion control where the trade-off between utility and path diversity can be investigated. In a network where there can be multiple routes between locations, each source is assigned a route according to a random allocation scheme

Fast Iterative Solver for Convection-Diffusion Systems with Spectral Elements

October 16, 2009
Author(s)
Aaron Lott, Howard Elman
We introduce a solver and preconditioning technique based on Domain Decomposition and the Fast Diagonalization Method that can be applied to tensor product based discretizations of the steady convection-diffusion equation. The method is based on iterative

Volume Estimation of Molded Artifacts by B-Splines

October 9, 2009
Author(s)
David E. Gilsinn, Bruce R. Borchardt, Amelia Tebbe
The volumes of two industrially molded non-metallic artifacts were estimated using surface data obtained by a coordinate measuring machine. A tensor product of B-splines was used to model the probed data points on the surface and the Divergence Theorem was

A Combinatorial Approach to Building Navigation Graphs for Dynamic Web Applications

September 20, 2009
Author(s)
Raghu N. Kacker, David R. Kuhn, James F. Lawrence, Wenhua Wang, Yu Lei, Sreedevi Sampath
Modeling the navigation structure of a dynamic web application is a challenging task because of the presence of dynamic pages. In particular, there are two problems to be dealt with: (1) the page explosion problem, i.e., the number of dynamic pages may be

Modeling Microstructures with OOF2

September 1, 2009
Author(s)
Andrew C. Reid, Rhonald Lua, R E. Garcia, Valerie R. Coffman, Stephen A. Langer
OOF2 is a program for computing the properties and behavior of material microstructures, beginning with an image of the microstructural geometry. OOF2 uses finite elements, but is designed to be used by materials scientists with little or no finite element

Estimating Volumes of Simulated Lung Cancer Nodules

July 15, 2009
Author(s)
David E. Gilsinn, Bruce R. Borchardt, Amelia Tebbe
Lung cancer is a disease of uncontrolled cell growth in tissues of the lung. Computed tomography (CT) shows promise in detecting lung cancers at earlier, more operable stages, when survival is better. CT scans generate multiple 2-D slice images of the lung

Lower Bounds for Accessing Information on Pure Pointer Machines

July 13, 2009
Author(s)
Brian D. Cloteaux, Desh Ranjan
We study the complexity of representing an array on a Pure Pointer Machine (PPM) or a pointer machine without arithmetic capabilities. In particular, we show that lower bounds in access time for information retrieval on a PPM arise from two different

Design of the DEMO Fusion Reactor Following ITER

July 1, 2009
Author(s)
Geoffrey B. McFadden, Paul R. Garabedian
Runs of the NSTAB equilibrium and stability code show there are many 3D solutions of the advanced tokamak problem subject to axially symmetric boundary conditions. These numerical simulations based on mathematical equations in conservation form predict

The contribution of lipid layer movement to tear film thinning and breakup

June 15, 2009
Author(s)
Geoffrey B. McFadden, Christopher Smith, Barbara A. Fink, Jason J. Nichols, Richard J. Braun
The purpose of this study is to investigate the origin of the tear film thinning between blinks, which can lead to tear film breakup and ocular surface damage. Two mechanisms of thinning are considered: "tangential flow" of the tear film along the surface

Atmospheric Retention of Man-made CO 2 Emissions

June 8, 2009
Author(s)
Bert W. Rust
Rust and Thijsse have shown that global annual average temperature anomalies T(t i) vary linearly with atmospheric CO 2 concentrations c(t i). The c(t i) can be related to man-made CO 2 emissions F(t i) by a linear regression model whose solution vector

Extending Measurement Science to Interactive Visualization Environments

January 30, 2009
Author(s)
Judith E. Terrill, William L. George, Terence J. Griffin, John G. Hagedorn, John T. Kelso, Thomas M. Olano, Adele P. Peskin, Steven G. Satterfield, James S. Sims, Jeffrey W. Bullard, Joy P. Dunkers, Nicos Martys, Agnes A. O'Gallagher, Gillian Haemer
We describe a method for creating a visual laboratory to interactively measure and analyze scientific data. We move the normal activities that scientists perform to understand their data into the visualization environment. The visualization environment is

Local Bounds on Effective Hamiltonians for Stabilizer Codes

January 22, 2009
Author(s)
Stephen Bullock, Dianne M. O'Leary
This paper introduces various notion of k-locality of stabilizer codes inherited from the associated stabilizer groups. A choice of generators for the group leads to a Hamiltonian with the code in its groundspace, while a Hamiltonian holding the code in
Displaying 301 - 325 of 446