CONTACT INFORMATION 


      
    Phone: (505) 667-5797
    Fax: (505) 665-4939
    Email: ahrens@lanl.gov 
 
 
 
 
 
 
 
 
 

PROFESSIONAL EXPERIENCE

    •    1997-present, Los Alamos National Laboratory
    •    Summer 1993-1994, Los Alamos National Laboratory
    •    Summer 1991, Thinking Machines Corporation
    •    Summer 1987-1989, General DataComm Incorporated

RESEARCH AREAS/EXPERTISE

    •    Technical expertise in the areas of visualization and parallel systems.
    •    Management experience as visualization R&D program manager and visualization team leader.

 EDUCATION

    •    Ph.D. Computer Science, University of Washington, Seattle, 1996.
    •    M.S. Computer Science, University of Washington, Seattle, 1992.
    •    B.S. Computer Science, University of Massachusetts, Amherst, 1989. 

CONTRIBUTIONS TO OPEN-SOURCE SOFTWARE

    •    ParaView - ParaView is an open-source visualization tool designed to handle extremely large datasets. I started the ParaView project and continue to play a significant role in its development.
    •   Parallel VTK - I developed parallel VTK - a parallel visualization software infrastructure. ParaView is built upon parallel VTK. 
    •    CMake

PUBLICATIONS

Book Chapters and Journal Articles

  • M. Graf, J. Ahrens, J. Patchett, H. Dahai, A. Balatsky, D. Modl, L. Monroe, N. Brown, E. Akhadov, "Integrated Nanotechnologies: To See is to Know: Visualization", SciDAC Review, Issue 10, Winter 2008. [PDF]

 • E. Anderson, J. Ahrens, K. Heitmann, S. Habib, C. SIlva, "Provenance in Comparative Analysis: A Study in Cosmology", Computing in Science and Engineering, Volume 10, Issue 3, pgs. 30-37, May-June 2008. [PDF]

 
•  K. Heitmann, Z. Lukic, P. Fasel, S. Habib, M. Warren, M. White, J. Ahrens, L. Ankeny, R. Armstrong, B. O'Shea, P.M. Ricker, V. Springel, J. Stadel, and H. Trac, "The Cosmic Code Comparison Project", Computational Science and Discovery, Volume 1, Issue 1, 2008. [PDF]

 • P. McCormick, J. Inman, J. Ahrens, J. Mohd-Yusof, G. Roth, S. Cummings, "Scout: A Data Parallel Programming Environment for Graphics Processors", Parallel Computing, 33(10-11), pgs. 648-662, 2007. 
 
 •  J. Ahrens, K. Heitmann, S. Habib, L. Ankeny, P. McCormick, J. Inman, R. Armstrong and K.L. Ma, "Quantitative and comparative visualization applied to cosmological simulations", Journal of Physics: Conference Series - Scientific Discovery Through Advanced Computing, Volume 46, 2006. [PDF]
 
 •  J. Ahrens, B. Geveci, C. Law, "ParaView: An End User Tool for Large Data Visualization", Visualization Handbook, Academic Press, 2005. [PDF]
 
 •  P. McCormick, J.Ahrens, "Large Data Visualization and Rendering: A Problem Driven Approach", Visualization Handbook, Academic Press, 2005.
 
 • J. Ahrens, K. Brislawn, K. Martin, B. Geveci, C. Law, M. Papka, "Large Scale Data Visualization Using Parallel Data Streaming", IEEE Computer Graphics and Applications, July-August 2001. [Abstract]
 
 • J. Kniss, P. McCormick, A. McPherson, J. Ahrens, J. Painter, A. Keahey, C. Hansen, "TRex: Interactive Texture Based Volume Rendering for Extremely Large Datasets", IEEE Computer Graphics and Applications, July-August 2001. [PDF]
 
 •  K. Keahey, P. Beckman and J. Ahrens, "Ligature: Component Architecture for High-Performance Applications",International Journal of High-Performance Computing Applications—Special Issue on Performance Modeling, Vol 14. No. 4, Winter 2000. [PDF]
 
 • P. McCormick and J. Ahrens, "Visualization of Wildfire Simulations", IEEE Computer Graphics 
and Applications, March-April 1998. [Abstract] [VIDEO]
 
 • R. Jakobovits, L. Lewis, J. Ahrens, L. Shapiro, S. Tanimoto and J. Brinkley, "A Visual Database Environment for Scientific Research",Journal of Visual Languages and Computing, Vol. 7, pp. 361-375, 1996. [Abstract]
  
Conference and Workshop Publications

 • J. Ahrens, L. Lo, B. Nouanesengsy, J. Patchett, and A. McPherson, "Petascale Visualization: Approaches and Initial Results", Ultrascale VIsualization Workshop, November 2008. [PDF of Presentation]
  
 • Emanuele Santos, Lauro Lins, James P. Ahrens, Juliana Freire and Claudio Silva, " A First Study on Clustering Collections of Workflow Graphs", International Provenance and Annotation Workshop, 2008. [PDF]
 
 • James Ahrens, Nehal Desai, Patrick McCormick, Ken Martin, Jonathan Woodring, "A Modular Extensible Visualization System Architecture For Culled Prioritized Data Streaming", Visualization and Data Analysis 2007, Proceedings of the SPIE - The International Society for Optical Engineering, Volume 6495, Jan. 2007. [PDF]
 
 • Andy Cedilnik, Berk Geveci, Kenneth Moreland, James Ahrens, and Jean Favre, "Remote Large Data Visualization in the ParaView Framework", Eurographics Symposium on Parallel Graphics and Visualization, pg. 163-170, May 2006. [PDF]
 
 • N. Fout, K-L. Ma, and J. Ahrens, "Time-Varying Multivariate Volume Data Reduction", ACM SAC 2005, March 2005. [PDF]
 
 • P. McCormick, J. Inman, J. Ahrens, G. Roth and C. Hansen, "Scout: A Hardware-Accelerated System for Quantitatively Driven Visualization and Analysis" Proceedings of the IEEE Visualization 2004 Conference , October 2004. [PDF]
 
 • A. Stompel, K-L. Ma, E. Lum, J. Ahrens, J. Patchett, "Scheduled Linear Image Compositing for Parallel Volume Rendering", IEEE Symposium on Parallel and Large-Data Visualization and Graphics, October 2003. [PDF]
 
 • C.C. Law, A. Henderson, J. Ahrens, "An Application Architecture for Large Data Visualization: A Case Study", IEEE Symposium on Parallel and Large-Data Visualization and Graphics, October 2001. [Abstract][PDF]
 
 • T.A. Keahey, P. McCormick, J. Ahrens, K. Keahey, "Qviz: a Framework for Querying and Visualizing Data", Proceedings of SPIE Vol. 4302 - Visual Data and Exploration and Analysis VIII, January 2001. [PDF]
 
 • K. Keahey, P. Beckman and J. Ahrens, "Ligature: Component Architecture for High-Performance Applications", 1st NASA Workshop on Performance-Engineered Information Systems, September 1998. [PDF]
 
 • J. Ahrens and J. Painter, "Efficient Sort-Last Rendering Using Compression-Based Image Compositing", Second Eurographics Workshop on Parallel Graphics and Visualization, September 1998. [PDF]
 
 • J. Ahrens, P. McCormick, J. Bossert, J. Reisner, J. Winterkamp, "Case Study: Wildfire Visualization", Proceedings of IEEE Visualization 1997, pp. 451-454, October 1997. [PDF]
 
 • J. Ahrens and C. Hansen, "Cost-Effective Data-Parallel Load Balancing", International Conference on Parallel Processing, Vol. 2, pp. 218-21, August 1995. [PDF]
 
 • L. Shapiro, S. Tanimoto, J. Brinkley, J. Ahrens, R. Jakobovits and L. Lewis, "A Visual Database System for Data and Experiment Management in Model-Based Computer Vision", Second CAD-Based Vision Workshop, pp. 64-72, February 1994.
 
 • F. Ortega, C. Hansen and J. Ahrens, "Fast Data Parallel Polygon Rendering", IEEE Supercomputing, pp. 709-18, November 1993. [PDF]
 
Invited Articles, Panels, Tutorials and Presentations
 
• Roadrunner Technical Seminars, Panel on Future Platforms,"Data Intensive Architectures", June 2008. [Video - Panel Discussion: Future Platforms, Ken Koch, Adolfy Hoisie, CCS-1 - Forward to 27:30 minutes]
 
 • Tutorial, CEA/EDF/INRIA summer school, "Methodes Avancees en Visualisation Scientifique", ParaView, 18-21 June 2007, Saint-Lambert-des-Bois, France. [Web]
 
 • Invited Presentation, LANL Earth and Environmental Sciences Division, Frontiers in Geoscience Colloquium, "Scientific Visualization from Desktops to Petaflops", November 2006.
 
 • Invited Presentation, SC06 Workshop on Ultra-Scale Visualization, "Quantitative and Comparative Visualization Applied to Cosmological Simulations", November 2006. [Web]
 
 • Invited Presentation, Office of Science - Scientific Discovery Through Advanced Computing Conference, "Quantitative and Comparative Visualization Applied to Cosmological Simulations", June 2006. [PDF][Video]
 
 • Member of panel on "Interoperability of Visualization Software and Data Models is Not an Achievable Goal", at IEEE Visualization 2003. [PDF]
 
 • K. Martin, G. Abram, J. Ahrens, R. Frank, P. Moran, "Tutorial on Large Scale Data Visualization and Rendering", IEEE Visualization, October 2001.
 
 • Member of panel on "Next-Generation Visualization Displays" at IEEE Visualization 2000. [PDF]
 
 • Invited presentation, "Using Linux Clusters for Parallel Visualization and Rendering", Extreme Linux Workshop, USENIX, June 1999.
 
 • Invited presentation, "An Evolving Infrastructure to Support Accelerated Strategic Computing Initiative (ASCI) Multi-Source Visualization and Data Analysis Needs", Ninth SIAM Conference on Parallel Processing for Scientific Computing, March 1999.
 
 • Invited article, A. McPherson, J. Painter, P. McCormick, J. Ahrens, C. Ragsdale, "Visualizations of Earth Processes for the American Museum of Natural History", Vol. 33, No. 1, Computer Graphics, February 1999. [PDF]
 
 • Member of panel on "Multi-Source Data Analysis Challenges" at IEEE Visualization 1998.

 CONNECTIONS