SCI Publications

2009


Y. Wan, H. Otsuna, C.-B. Chien, C.D. Hansen. “An Interactive Visualization Tool for Multi-channel Confocal Microscopy Data in Neurobiology Research,” SCI Technical Report, No. UUSCI-2009-001, SCI Institute, University of Utah, 2009.


Y. Wan, H. Otsuna, C.-B. Chien, C.D. Hansen. “An Interactive Visualization Tool for Multi-Channel Confocal Microscopy Data in Neurobiology Research,” In IEEE Transactions on Visualization and Computer Graphics, Proceedings of the 2009 IEEE Visualization Conference, Vol. 15, No. 6, pp. 1489--1496. Sept/Oct, 2009.


D.F. Wang, R.M. Kirby, C.R. Johnson. “Finite Element Discretization Strategies for the Inverse Electrocardiographic (ECG) Problem,” In Proceedings of the 11th World Congress on Medical Physics and Biomedical Engineering, Munich, Germany, Vol. 25/2, pp. 729-732. September, 2009.


D.F. Wang, R.M. Kirby, C.R. Johnson. “Finite Element Refinements for Inverse Electrocardiography: Hybrid-Shaped Elements, High-Order Element Truncation and Variational Gradient Operator,” In Proceeding of Computers in Cardiology 2009, Park City, September, 2009.


Y. Wang, A.R.C. Paiva, J.C. Principe, J.C. Sanchez. “Sequential Monte Carlo Point Process Estimation of Kinematics from Neural Spiking Activity for Brain Machine Interfaces,” In Neural Computation, Vol. 21, No. 10, pp. 2894--2930. 2009.


D. Xiu, J. Shen. “Efficient Stochastic Galerkin Methods for Random Diffusion Equations,” In Journal of Computational Physics, Vol. 228, No. 2, pp. 266--281. 2009.
DOI: 10.1016/j.jcp.2008.09.008

ABSTRACT

We discuss in this paper efficient solvers for stochastic diffusion equations in random media. We employ generalized polynomial chaos (gPC) expansion to express the solution in a convergent series and obtain a set of deterministic equations for the expansion coefficients by Galerkin projection. Although the resulting system of diffusion equations are coupled, we show that one can construct fast numerical methods to solve them in a decoupled fashion. The methods are based on separation of the diagonal terms and off-diagonal terms in the matrix of the Galerkin system. We examine properties of this matrix and show that the proposed method is unconditionally stable for unsteady problems and convergent for steady problems with a convergent rate independent of discretization parameters. Numerical examples are provided, for both steady and unsteady random diffusions, to support the analysis.

Keywords: Generalized polynomial chaos, Stochastic Galerkin, Random diffusion, Uncertainty quantification


D. Xiu. “Fast Numerical Methods for Stochastic Computations: a Review,” In Communications in Computational Physics, Vol. 5, No. 2-4, pp. 242--272. 2009.
DOI: 10.1.1.148.5499

ABSTRACT

This paper presents a review of the current state-of-the-art of numerical methods for stochastic computations. The focus is on efficient high-order methods suitable for practical applications, with a particular emphasis on those based on generalized polynomial chaos (gPC) methodology. The framework of gPC is reviewed, along with its Galerkin and collocation approaches for solving stochastic equations. Properties of these methods are summarized by using results from literature. This paper also attempts to present the gPC based methods in a unified framework based on an extension of the classical spectral methods into multi-dimensional random spaces.

Keywords: Stochastic differential equations, generalized polynomial chaos, uncertainty quantification, spectral methods


F. Zhang, E.R. Hancock, C. Goodlett, G. Gerig. “Probabilistic White Matter Fiber Tracking using, Particle Filtering and von Mises-Fisher Sampling,” In Medical Image Analysis, Vol. 13, No. 1, pp. 5--18. 2009.
PubMed ID: 18602332

2008


G. Adluru, E.V.R. DiBella, C.J. McGann. “Data Acquisition and Reconstruction of Undersampled Radial MR Myocardial Perfusion,” In Proceedings of the 11th Annual Scientific Sessions of the Society for Cardiovascular Magnetic Resonance (SCMR) 2008, pp. 215. 2008.


G. Adluru, E.V.R. DiBella. “A Comparison of L1 and L2 Norms as Temporal Constraints for Reconstruction of Undersampled Dynamic Contrast Enhanced Cardiac Scans with Respiratory Motion,” In Proceedings of the 16th Scientific Meeting and Exhibition of the International Society for Magnetic Resonance in Medicine (ISMRM) 2008, pp. 340. 2008.


G. Adluru, E.V.R. DiBella. “Data Reordering for Improved Constrained Reconstruction from Undersampled k-space Data,” In Proceedings of the 16th Scientific Meeting and Exhibition of the International Society for Magnetic Resonance in Medicine (ISMRM) 2008, pp. 3153. 2008.


A.E. Anderson, B.J. Ellis, C.L. Peters, J.A. Weiss. “Cartilage Thickness: Factors Influencing Multidetector CT Measurements in a Phantom Study,” In Radiology, Vol. 246, No. 1, pp. 133-141. 2008.
PubMed ID: 18982614


A.E. Anderson, B.J. Ellis, S.A. Maas, C.L. Peters, J.A. Weiss. “Validation of Finite Element Predictions of Cartilage Contact Pressure in the Human Hip Joint,” In ASME Journal of Biomechanical Engineering, Vol. 130, No. 3, pp. 051008-1--10. May, 2008.


E.W. Anderson, J. Ahrens, K. Heitmann, S. Habib, C.T. Silva. “Provenance in Comparative Analysis: A Study in Cosmology,” In Computing in Science and Engineering, Vol. 10, No. 3, pp. 30--37. 2008.


A.E. Anderson, B.J. Ellis, C.L. Peters, J.A. Weiss. “Factors Influencing Cartilage Thickness Measurements with Multi-Detector CT: A Phantom Study,” In Radiology, Vol. 246, No. 1, pp. 144-141. 2008.


A. Baptista, B. Howe, J. Freire, D. Maier, C.T. Silva. “Scientific Exploration in the Era of Ocean Observatories,” In Computing in Science and Engineering, Vol. 10, No. 3, pp. 53--58. 2008.


L. Bavoil, S.P. Callahan, and C.T. Silva. “Robust Soft Shadow Mapping with Depth Peeling,” In Journal of Graphics Tools, Vol. 13, No. 1, pp. 19--30. 2008.


E.W. Bethel, H. Childs, A. Mascarenhas, V. Pascucci, Prabhat. “Scientific Data Management Challenges in High Performance Visual Data Analysis,” In Scientific Data Management: Challenges, Existing Technology, and Deployment, Chapman Hall/CRC Press, 2008.


D. Brayford, M. Turner, W.T. Hewitt. “A Physical Model for the Polarized Scattering of Light,” In Proceedings of The sixth Theory and Practice of Computer Graphics 2008 Conference (TPCG08), University of Manchester, UK, Note: Best Paper Award, June, 2008.


K. Buerger, P. Kondratieva, J. Krüger, R. Westermann. “Importance-Driven Particle Techniques for Flow Visualization,” In Proceedings of IEEE VGTC PacificVis 2008, pp. 71--78. 2008.