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Timothy J. Blattner, Walid Keyrouz, Milton Halem, Shuvra S. Bhattacharyya, Mary C. Brady
The scalability of applications is a key requirement to improving performance in hybrid and cluster computing. Scheduling code to utilize parallelism is difficult, particularly when dealing with dependencies, memory management, data motion, and processor
Jose Gomez-Ballesteros, Juan Burgos, Pin A. Lin, Renu Sharma, Perla Balbuena
The dynamic evolution of nanocatalyst particle shape and carbon composition is examined through the initial stages of the single walled-carbon nanotubes chemical vapor deposition synthesis via classical reactive and ab initio molecular dynamics simulations
We consider the unique issues related to software sustainability that accompany scientific codes that employ stochastic algorithms. These are codes that often implement Monte Carlo methods (MCMs). We will focus our attention on ZENO, a code of interest at
Experimental reproducibility is a cornerstone of the scientific method. The ease of achieving its counterpart in computing, numerical reproducibility, was one of the core assumptions underpinning the growth of scientific computing over the past several
Jeffrey T. Fong, Nathanael A. Heckert, James J. Filliben, Pedro V. Marcal, Robert Rainsberger
Uncertainty in COMSOL finite element simulations due to (a) mesh-induced truncation errors, and (b) model parameter uncertainties, is estimated using a nonlinear least squares logistic distribution fit method, and a design-of-experiments approach
Nathan A. Hotaling, Kapil Bharti, Haydn Kriel, Carl G. Simon Jr.
Despite the growing use of nanofiber scaffolds for tissue engineering applications, there is not a validated, readily available (commercial or open source) solution for rapid, automated analysis of nanofiber diameter from scanning electron microscope (SEM)
Antonio Cardone, Aaron Bornstein, Harish C. Pant, Mary C. Brady, Ram D. Sriram, Sergio Hassan
A method is proposed to study protein-ligand binding in a system governed by specific and non-specific interactions. Strong associations lead to narrow conformational distributions in the proteins configuration space; weak and ultra-weak associations lead
Parastoo Delgoshaei, Mark Austin, Amanda Pertzborn
This paper describes a new semantic platform infrastructure for model-based systems engineering, requirements traceability, and system simulation and assessment of cyberphysical systems (CPSs). When fully developed this environment will support the
Timothy Blattner, Walid Keyrouz, Joe Chalfoun, Bertrand C. Stivalet, Mary C. Brady, Shujia Zhou
Researchers in various fields are using optical microscopy to acquire very large images, 10K--200K of pixels per side. Optical microscopes acquire these images as grids of overlapping partial images (thousands of pixels per side) that are then stitched
The method of Sinkhorn balancing that starts with a non-negative square matrix and iterates to produce a related doubly stochastic matrix has been used with some success to estimate the values of the permanent in some cases of physical interest, However it
Isabel M. Beichl, Amanda A. Streib, Noah S. Streib, Francis Sullivan
A large portion of the complexity inherent to the Ising model can be captures with a trivial amount of computation. in this work, we support this claim by defining an approximation to the partition function and other thermodynamic quantities of the Ising
Diverse measurement contexts require estimates of time varying quantities. Ideally the measurement device responds to signal variations significantly more rapidly than the modulation of the signal itself. If so, then well-developed techniques may be used
The vast majority of points collected with coordinate measuring machines are not used in isolation; rather, collections of these points are associated with geometric features through fitting routines. In manufacturing applications, there are two
DLMF was released to the public in May 2010 and is now completing its 3rd year online. As a somewhat early adopter of large-scale MathML content online, and exposing a math-aware search engine to the public, the project encountered situations distinct from
Jeffrey Fong, Carlos A. Cimini, Jose D. Melo, N. Alan Heckert, James J. Filliben
Composite material property databases are important information to guide designers. Aeronautical companies spend a great deal of effort in terms of money and labor to build such databases, which are considered confidential. The development of a single
Amanda A. Streib, Noah S. Streib, Isabel M. Beichl, Francis Sullivan
We present a new approach to a classical problem in statistical physics: estimating the partition function and other thermodynamic quantities of the ferromagnetic Ising model. Markov chain Monte Carlo methods for this problem have been well-studied
Walid Keyrouz, Timothy J. Blattner, Bertrand C. Stivalet, Joe Chalfoun, Mary C. Brady, Shujia Zhou
We present a hybrid CPU-GPU approach for the Fourier-based stitching of optical microscopy images. This system achieves sub-minute stitching rates with large grids; it stitches a grid of 59x42 tiles in 26 seconds on a two-CPU (8 physical cores) & two-GPU
Jeffrey T. Fong, William F. Guthrie, James J. Filliben, Nathanael A. Heckert
In this paper, we use a Bayesian quantitative nondestructive evaluation (QNDE) approach to estimating the remaining life of aging structures and components. Our approach depends on in-situ NDE measurements of detectable crack lengths and crack growth rates
Jeffrey T. Fong, Nathanael A. Heckert, James J. Filliben
We begin with a review of the fatigue design methodology for new pressure vessels and piping, based on both deterministic and stochastic approaches. We will then prove that the same methodology for estimating the remaining life of aging pressure vessels
Peter Bajcsy, Antoine Vandecreme, Benjamin J. Long, Paul Khouri Saba, Joe Chalfoun, Luigi Marini, Rob Kooper, Michal Ondrejcek, Kenton McHenry, Smruti Padhy
Versus is a framework for the execution and dissemination of customizable content-based file comparison methods. Given digital objects such as files, database entries, or in-memory data structures, we are interested in establishing their proximity (i.e
Cell measurements are derived frequently from the results of pixel classification and contiguous region segmentation of microscopy images. Image segmentation is accomplished by classifying image pixels based on high dimensional image features computed from