Roy David Williams

roy at caltech dot edu
626 395 3670

My work focuses on providing people with meaningful access to scientific and technical data, as well as learning from, making decisions from, and preserving that data.

My career began with a degree in mathematics, then a PhD in nuclear physics and mathematical physics. I worked in physics a few more years, then worked with the new architecture computers, rebuilding scientific simulation codes for parallel machines, and making new codes with unstructured meshes and dynamic load balancing (1991). I was building web applications in 1996, delivering Earth remote-sensing data over the internet. I worked with the LIGO (gravitational waves) project, introducing them to databases and XML, and built science gateways for the US Teragrid project. I was with the Virtual Observatory from the start, as architect, also creating in large part the VOTable and VOEvent standards, now widely used.

The emphasis now is open data for the LIGO project. The challenge of open data is to take valuable, yet complex, science data, and make it broadly available to the general public in a way that they can use, free of restriction. Here the "public" ranges from schoolchildren to professional scientist, and the "use" of the data can range from important discoveries that were not found by the original team, down to children at play. Once data is open, new searches can be made, and unconventional theories can be tested. Weather data from NOAA was made open in the 1970's, growing a new industry; and GPS data was opened in the 1980's, changing our lives with immediate location services. In 2013, the US Office of Science and Technology mandated that "direct results of federally funded scientific research are made available to and useful for the public, industry, and the scientific community. Such results include peer-reviewed publications and digital data.


Contents

Open Data
Astronomical Events and Transients
Gravitational waves and LIGO
Virtual Observatory
Digital Data Access
Astronomy
Cyberinfrastucture and Grids and Clouds
Mathematics
Parallel Computational Fluid Dynamics
Materials science
Nuclear physics and mathematical physics

Open Data


LIGO Open Science Center: data releases from the LIGO project.
http://losc.ligo.org. 2013 - present.

LIGO Data Management Plan Stuart Anderson and Roy Williams, 2013
Click here.

Community Input for LIGO Open Data edited by Roy Williams, Christian Ott, Steve Groom, 2012
Click here.

LIGO Open Data Survey Results Roy Williams, 2011
Click here.

Scientific Data Mining Integration and Visualization
Bob Mann, Roy Williams, Malcolm Atkinson, Ken Brodlie, Amos Storkey, Chris Williams,
report of a workshop held in Edinburgh, 24-25 October 2002. PDF
Agent based data management in digital libraries
Y.Y. Yang, O.F. Rana, D. W. Walker, R. D. Williams
Parallel Computing 28 (5): 773-792 (2002)

Report of the European Union - United States Workshop on Large Scientific Databases
Roy Williams, Paul Messina, Fabrizio Gagliardi, John Darlington, and Giovanni Aloisio
October 1999
html, pdf, text.

Special issue: Interfaces to Scientific Digital Archives
ed. Roy Williams
Future Generation Computer Systems 16 (1): VII-VIII (1999)

Interfaces to Scientific Data Archives
Report of the NSF Workshop
Roy Williams, Julian Bunn, Reagan Moore and James Pool,
May 1998. PDF or HTML.

A High-Performance Active Digital Library
Roy Williams and Bruce Sears
Parallel Computing 24 (12-13): 1709-1711 (1998). PDF

The Digital Puglia Project: An active digital library of remote sensing data
G. Aloisio, M. Cafaro, R. Williams
Lecture Notes in Computer Science 1593: 563-572 (1999)


Astronomical events and transients


Responding to the Event Deluge Roy D. Williams, Scott D. Barthelmy, Robert B. Denny, Matthew J. Graham, John Swinbank
Proceedings of SPIE Observatory Operations, Amsterdam, 2012 Click here.

Skyalert: authoring, dissemination, annotating, mining, and messaging of immediate astronomical events.
http://skyalert.org. 2009 - 2013.

Skyalert: Real-time Astronomy for You and Your Robots
R. D. Williams, S. G. Djorgovski, A. J. Drake, M. J. Graham, A. Mahabal.
Proc. ADASS XVIII (2008), PASP, eds. D. Bohlender, P. Dowler and D. Durand PDF

VOEventNet: Dissemination of event packets via International Backbone R.D. Williams, A.J. Drake, M.J. Graham et al
Click here.

Transient Event Notification with VOEvent
Williams, R.D.; Seaman, R.L.
in The National Virtual Observatory: Tools and Techniques for Astronomical Research eds. Graham M.J., Fitzpatrick M.F., McGlynn T.A. ASP Conference Proceedings 382 (2007). PDF

VOEventNet: An Open Source of Transient Alerts for Astronomers
Data warehouse for Catalina Real-time Transient Survey, Palomar-Quest, NASA/GCN events. 2005 A.J. Drake and R.D. Williams. Click here.

Astronomical network event and observation notification
White R.R., Allan A., Barthelmy S., Bloom J., Graham M.J., Hessman F.V., Marka S., Rots A., Scholberg K., Seaman R., Stoughton C., Vestrand W.T., Williams R., Wozniak P.R.,
Astronomische Nachrichten, 327 (2006) 775.

Sky Event Reporting Metadata (VOEvent)
R. Seaman, R.D. Williams, A. Allan, S. Barthelmy, J. Bloom, M. Graham, F. Hessman, S. Marka, A. Rots, C. Stoughton, T. Vestrand, R. White, P. Wozniak,
A Recommendation of the International Virtual Observatory Alliance, 2006. HTML

Transient Event Reporting and Response with VOEvent
Seaman, R.; Allan, A.; Williams, R.
Astronomical Data Analysis Software and Systems ASP Conference Series, Vol. 394, Eds R.W. Argyle, P.S. Bunclark, and J.R. Lewis., p.213 (2007) PDF

Google Sky mashup
Roy Williams and Andrew Drake
Real-time display of events from multiple streams. 2007. (bring up the Google Earth/Sky client, click Current Sky Events and VOEventNet)., or click here.

Worldwide Telescope mashup
Roy Williams
Real-time display of events from multiple streams, 2009. Click here (use Safari or IE).

Exploring the Time Domain with Synoptic Sky Surveys S. G. Djorgovski, A. A. Mahabal, A. J. Drake, M. J. Graham, C. Donalek and R. Williams
Proceedings of the International Astronomical Union / Volume 7 / Symposium S285 / September 2011, pp 141-146
Click here.

Real-Time Classification of Transient Events in Synoptic Sky Surveys Ashish A. Mahabal, C. Donalek, S. G. Djorgovski, A. J. Drake, M. J. Graham, R. Williams, Y. Chen, B. Moghaddam and M. Turmon
Proceedings of the International Astronomical Union / Volume 7 / Symposium S285 / September 2011, pp 355 - 357
Click here.

Automated probabilistic classification of transients and variables
Mahabal, A., Djorgovski, S. G.; Turmon, M., Jewell, J.; Williams, R. D.; Drake, A. J.; Graham, M. G.; Donalek, C.; Glikman, E.
Astron. Nacht. 329 (2008) 288

New Approaches to Object Classification in Synoptic Sky Surveys
Donalek C., Mahabal A., Djorgovski S.G., Marney S., Drake A., Glikman E., Graham M.J., Williams R.
in Classification and Discovery in Large Astronomical Surveys. AIP Conference Proceedings, Vol. 1082, p. 252

Towards Real-time Classification of Astronomical Transients
Mahabal A., Djorgovski S.G., Williams R., Drake A., Donalek C., Graham M.J., Moghaddam B., Turmon M., Jewell J., Khosla A., Hensley B.
in Classification and Discovery in Large Astronomical Surveys. AIP Conference Proceedings, Vol. 1082, p. 287.

Palomar-QUEST: A case study in designing sky surveys in the VO era
Matthew J. Graham, Roy Williams, S. G. Djorgovski, Ashish Mahabal, Charles Baltay, Dave Rabinowitz, Anne Bauer, Jeff Snyder, Nick Morgan, Peter Andrews, Alexander S Szalay, Robert J. Brunner and Jim Musser
Astronomical Data Analysis Software & Systems XIV, 24 - 27 October, 2004, Pasadena, California. PDF

Exploring the Time Domain with the Palomar-QUEST Sky Survey
A. Mahabal, S.G. Djorgovski, M. Graham, R. Williams, B. Granett, M. Bogosavljevic, C. Baltay, D. Rabinowitz, A. Bauer, P. Andrews, N. Morgan, J. Snyder, N. Ellman, S. Duffau, J. Musser, S. Mufson, M. Gebhard, R. Brunner.
Astronomical Data Analysis Software & Systems XIV, 24 - 27 October, 2004, Pasadena, California. PDF

Time Domain Explorations With Digital Sky Surveys
Ashish A. Mahabal, S. G. Djorgovski, M. J. Graham, Priya Kollipara, Benjamin Granett, Elisabeth Krause, Roy Williams, M. Bogosavljevic, C. Baltay, D. Rabinowitz, A. Bauer, P. Andrews, N. Ellman.
Astronomical Data Analysis Software and Systems XIV. Astronomical Society of the Pacific Conference Series. Astronomical Society of the Pacific, San Francisco, CA, P2.2.7.


Gravitational waves

Observation of Gravitational Waves from a Binary Black Hole Merger LIGO Scientific Consortium
Phys. Rev. Lett. 116, 061102

Gravitational Waves and Time-Domain Astronomy Joan Centrella, Samaya Nissanke and Roy Williams
Proceedings of the International Astronomical Union / Volume 7 / Symposium S285 / September 2011, pp 191-198 Click here.

Applications of virtual data in the LIGO experiment
Ewa Deelman, Carl Kesselman, Roy Williams, et al.
Lecture Notes in Computer Science 2328: 23-34 2002

A Virtual Data Grid for LIGO
Ewa Deelman, Carl Kesselman, Roy Williams, Albert Lazzarini, Thomas A. Prince, Joe Romano and Bruce Allen
Lecture Notes in Computer Science, vol 2110 (2001) pp 3-12
PDF

Network data analysis server (NDAS) prototype development
Szabi Marka, Benoit Mours, Roy Williams
Classical and Quantum Gravity 19 (7): 1537-1540 (2002)

XSIL: Extensible Scientific Interchange Language
Kent Blackburn, Albert Lazzarini, Tom Prince and Roy Williams
Lect. Notes. Comp. Sci. 1593 (1999) 513.
PDF


Virtual Observatory


Using the VO to Study the Time Domain Rob Seaman, Roy Williams, Matthew Graham and Tara Murphy
Proceedings of the International Astronomical Union / Volume 7 / Symposium S285 / September 2011, pp 221 - 226
Click here.

VIM: Visual Integration and Mining
Integrate data from multiple positions and datasets. Click here

VIM: A Tool to Explore Your Sources
Williams, R. D.
in Astronomical Data Analysis Software and Systems ASP Conference Series, Vol. 394, eds. Robert W. Argyle, Peter S. Bunclark, and James R. Lewis., p.173

National Virtual Observatory Summer School 2008
Roy Williams, Faculty Chair
Organized the content and teaching for a two-week intensive course on the Virtual Observatory, September 2008, Santa Fe, New Mexico. Details here.

Describing Data and Data Collections in the VO
Kent, B.R.; Hanisch, R.J.; Williams, R.D.
in The National Virtual Observatory: Tools and Techniques for Astronomical Research, eds. Graham M.J., Fitzpatrick M.F., McGlynn T.A. ASP Conference Proceedings, vol. 382. PDF

VOTable Format Definition
Francois Ochsenbein, Roy Williams, Clive Davenhall, Daniel Durand, Pierre Fernique, David Giaretta, Robert Hanisch, Tom McGlynn, Alex Szalay, Mark B. Taylor, Andreas Wicenec,
A Recommendation of the International Virtual Observatory Alliance. HTML

An IVOA Standard for Unified Content Descriptors
S. Derriere, N. Gray, R. Mann, A. Preite Martinez, J. McDowell, T. Mc Glynn, F. Ochsenbein, P. Osuna, G. Rixon, R.D. Williams.
A Recommendation of the International Virtual Observatory Alliance. HTML

Virtual Observatory: From Concept to Implementation
S. G. Djorgovski and R. Williams
In: Science with Wavelengths on Human Scales, ASPCS, vol. 3xx. ASPCS PDF

Lectures on Virtual Observatory Astronomy with Large and Complex Data Sets and Trends in e-Science
Roy Williams and George Djorgovski
BRAVO Workshop, Sao Jose dos Campos, Brazil, 2007 Link

The IVOA in 2007: Assessment and Future Roadmap
Roy Williams and the IVOA Technical Coordination Group
International Virtual Observatory Alliance, PDF

The IVOA in 2006: Assessment and Future Roadmap
Roy Williams and the IVOA Technical Coordination Group
International Virtual Observatory Alliance, PDF.

The IVOA in 2005: Assessment and Future Roadmap
Roy Williams and the IVOA Technical Coordination Group
International Virtual Observatory Alliance, PDF

Virtual Observatory Architecture Overview
Roy Williams, Bob Hanisch, Tony Linde, Johnathan McDowell, Reagan Moore, François Ochsenbein, Masatoshi Ohishi, Guy Rixon, Alex Szalay, Doug Tody,
International Virtual Observatory Alliance, HTML

A Virtual Observatory Vision based on Publishing and Virtual Data
Roy Williams, Reagan Moore, Robert Hanisch. PDF

XML and Web Services for Astronomers
Roy Williams and Robert Brunner
tutorial at ADASS 2002, Baltimore, October 2002. PPT

Grids and the Virtual Observatory
Roy Williams
in Grid Computing: Making The Global Infrastructure a Reality by Fran Berman, Anthony J.G. Hey, and Geoffrey Fox, Wiley, 2003, pp 837-858. PDF

Approaches to Federation of Astronomical Data
Roy Williams
in Virtual Observatories of the Future, eds. R. J. Brunner, S. G. Djorgovski, and A. S. Szalay, Astronomical Society of the Pacific, Conference Series 225. November 2000. PDF


Astronomy


First Results from the Catalina Real-time Transient Survey
A.J. Drake, S.G. Djorgovski, A. Mahabal, E. Beshore, S. Larson, M.J. Graham, R. Williams, E. Christensen, M. Catelan, A. Boattini, A. Gibbs, R. Hill, R. Kowalski, Astrophysical J. 696 (2009) 870. PDF

Multi-Wavelength Image Space: Another Grid-Enabled Science
Roy Williams, Bruce Berriman, Ewa Deelman, John Good, Joseph Jacob, Carl Kesselman, Carol Lonsdale, Seb Oliver, Tom Prince
Concurrency & Computation, vol 15 (2003), pp 539-549. PDF,

Object detection in multi-epoch data
G. Jogesh Babu, Ashish Mahabal, S. G. Djorgovski, R. Williams
Statistical Methodology, Volume 5, Issue 4, p. 299-306. PDF

Sub-Saturation Phases of Nuclear Matter
R. D. Williams and S. E. Koonin,
Nucl. Phys. A345, 844 (1984)

Bound-State Decay of Rhenium-187
R. D. Williams, W. A. Fowler and S. E. Koonin,
Astrophys. J. 281, 363 (1984)


Cyberinfrastucture and Grids and Clouds


Astronomy with Cutting-Edge ICT: From Transients in the Sky to Data over the Continents (India-US) Ashish Mahabal, Ajit Kembhavi, Roy Williams and Sharmad Navelkar
Click here.

Django for Web Applications
Part of a Caltech seminar series, 2009. PDF

Putting your Web Application in the Cloud
Part of a Caltech seminar series, 2009. PDF

Data-Intensive Computing in the 21st Century Ian Gorton, Paul Greenfield, Alex Szalay, Roy Williams
Computer 05/2008; DOI:10.1109/MC.2008.122 Click here.

Cloudspace: virtual environments in the VO
Graham M.J., Williams R.D. in Astronomical Data Analysis Software and Systems XVII, eds. Lewis J., Argyle R., Bunclarke P., Evans D. & Gonzales-Solares E. ASP Conference Proceedings, San Francisco, p. 73

Programmatic Interfaces, Grid Computing with NESSSI
in The National Virtual Observatory: Tools and Techniques for Astronomical Research. eds. Graham M.J., Fitzpatrick M.F., McGlynn T.A. ASP Conference Proceedings, vol. 382 PDF

HotGrid: Graduated Access to Grid-Based Science Gateways
Williams, R. Steenberg, C. Bunn, J. Lect. Notes Computer Sci. 3470 (2005) 78. PDF

An Architecture for Scaling NVO Services to TeraGrid
Roy Williams, Bob Hanisch, Joe Jacob, Ray Plante and Alex Szalay
Technical Report. PDF

Web access to supercomputing
G. Aloisio, M. Cafaro, C. Kesselman, R. Williams
Computational Science and Engineering 3 (6): 66-72 (2001)

Grid computing on the web using the globus toolkit
G. Aloisio G, M. Cafaro, P. Falabella, R. Williams
Lecture Notes in Computer Science 1823: 32-40 (2000)

An XML Architecture for High-Performance Web-Based Analysis of Remote-Sensing Archives
Giovanni Aloisio, Giovanni Milillo, and Roy Williams
Future Generation Computing Systems 16 (1): 91-100 NOV 1999. PDF.

Paraflow: A dataflow distributed data-computing system
Roy Williams and Bruce Sears
Lecture Notes in Computer Science 1401: 556-565 (1998)

Metacomputing - From ideas to real implementations
Wolfgang Nagel and Roy Williams
Parallel Computing 24 (12-13): 1709-1711 (1998)

A Distributed Web-based Metacomputing Environment
G. Aloisio, M. Cafaro, P. Messina, R. D. Williams,
in HPCN97, Vienna, April 1997. PDF

Parallel Computing Works!
G. C. Fox, R. D. Williams and P. C. Messina,
Morgan-Kaufmann, San Francisco, 1994 (available from Amazon)

Benchmarking Advanced Architecture Computers
P. Messina, C. F. Baillie, E. W. Felten, P. G. Hipes, D. W. Walker, R. D. Williams, et al,
Concurrency, 2, 195 (1990)


Mathematics


Analysis of Shear Layers in a Fluid with Temperature-Dependent Viscosity
D. J. Estep, S. M. Verduyn Lunel, and R. D. Williams
J. Comp. Physics, vol 173 (2001), pp 17-60. PDF

Video: Letter R formed by evolution of non-uniform Gray-Scott model, 1999. Click here.

The Formation, Structure, and Stability of a Shear Layer in a Fluid with Temperature-Dependent Viscosity
D. J. Estep, S. M. Verduyn Lunel, and R. D. Williams
June 2000
PDF.

Estimating the Error of Numerical Solutions of Systems of Nonlinear Reaction-Diffusion Equations
D. J. Estep, M. G. Larsen, and R. D. Williams
Memoirs Amer. Math. Soc., 146 (2000) number 696, pp 1-109. PDF

Error Estimation for Numerical Differential Equations
D. J. Estep, S. M. Verduyn Lunel and R. D. Williams
IEEE Antennas and Propagation 38 (2): 71-76 (1996). PDF

Accurate Parallel Integration of Large Sparse Systems of Differential Equations
D. J. Estep and R. D. Williams
Mathematical Models and Methods in Applied Sciences 6 (4): 535-568 (1996). PDF


Parallel Computational Fluid Dynamics



These pictures show a parallel 3D adaptive unstructured mesh. The first two images show the pressure on the outside of a pipe of square cross section, that has a slot in it. Fluid moves from the top right to the bottom left; the main bow shock is reflected multiple times as the fluid moves down the pipe. The third image shows the surface of the unstructured tetrahedral mesh that was used for the computation; the mesh has self-adapted to the pressure gradient, meaning a finer mesh at the shocks. The fourth picture shows the decomposition of the mesh among 512 parallel processors: each colour represents a differentr processor. Adaptivity is evident here also, as each processor has an equal number of tetrahedral mesh cells.

A Test Suite for High-Performance Parallel Java
Jochem Hauser, Thorsten Ludewig, Roy Williams, Ralf Winkelmann, Torsten Gollnick, Sharon Brunett, Jean Muylaert
Advances in Engineering Software 31 (8-9): 687-696 (2000)

A Pure Java Parallel Flow Solver
Jochem Hauser, Thorsten Ludewig, Torsten Gollnick, Ralf Winkelmann, Roy Williams, Jean Muylaert, and Martin Spel
AIAA paper 99-0549, proceedings of 37th Aerospace Sciences Meeting, Reno NV, Jan 1999.
PDF.

Strategies for Parallel and Numerical Scalability of CFD Codes
Ralf Winkelmann, Jochem Hauser and Roy Williams
Computational Methods in Applied Mechanical Engineering. 174 (3-4): 433-456 (1999). PDF
(image shows Huygens craft, that landed on Titan Jan 2004)

A Tangled Web Strategy for Numerical and Parallel Scalability in Aerospace Simulation
J. Haeuser, R. D. Williams and R. Winkelmann
Proceedings of CFD97, University of Victoria, Canada, 25-27 May 1997. PDF.

Efficient Convergence Acceleration for Parallel CFD Codes
R.D. Williams, J. Hauser and R. Winkelmann,
Proceedings of the Parallel CFD '96 conference, Capri, Italy
July 1996. PDF

A Newton-GMRES Method for the Parallel Navier-Stokes Equations
J. Hauser, R.D. Williams, H.-G. Paap, M. Spel, J. Muylaert and R. Winkelmann
Proceedings of the Parallel CFD '95 conference, Pasadena, California
July 1995. PDF

Strategies for Parallelizing a Navier-Stokes Code on the Intel Touchstone Machines
J. Häuser and R. D. Williams,
Int. J. Num. Meth. Fluids 15 (1992) 51. PDF

Adaptive Parallel Meshes with Complex Geometry
R. D. Williams
in Numerical Grid Generation for Computational Fluid Dynamics, ed. A.-S. Arcilla et. al., Elsevier North-Holland, Amsterdam, 1991. PDF

Performance of Dynamic Load Balancing Algorithms for Unstructured Mesh Calculations
R. D. Williams,
Concurrency, 3 (1991) 457. PDF

Strategies for Parallelizing a Navier-Stokes Code on the Intel Touchstone Machines
J. Häuser and R. D. Williams,
Int. J. Numerical Methods in Fluids, 15, 51 (1992)

Voxel Databases: A Paradigm for Parallelism with Spatial Structure
R. D. Williams,
Concurrency, 4 (1992) 619. PDF

Adaptive Parallel Meshes with Complex Geometry
C. F. Baillie, R. D. Williams, S. M. Catterall and D. A. Johnston
Nucl. Phys B348, 543 (1991)

Performance of Dynamic Load Balancing Algorithms for Unstructured Mesh Calculations
R. D. Williams,
Concurrency, 3, 457 (1991)

Distributed Irregular Finite Elements
R. D. Williams
A software package for distributed parallel computing with unstructured triangular and tetrahedral meshes. PDF users manual

Supersonic Flow in Parallel with an Unstructured Mesh
R. D. Williams
Concurrency, 1, 51 (1989)

Free-Lagrange Hydrodynamics in Parallel
R. D. Williams
Parallel Computing 7, 439 (1988)


Materials science


Two Transitions in Tangentially Anchored Nematic Droplets
R. D. Williams
J. Phys. A19, 3211 (1986) PDF

Critical Spin Dynamics of Europium Oxide
S. W. Lovesey and R. D. Williams
J. Phys. C19, L253 (1986)

Scattering Response of a Phonon Damped Harmonic Oscillator
R. D. Williams, S. W. Lovesey and W. Renz,
Z. Physik B64, 129 (1986)

Neutron Scattering from a Substitutional Mass Defect
R. D. Williams and S. W. Lovesey
Z. Physik B62, 413 (1986)

The Coupling of Phonons to a Helium Atom Adsorbed on Graphite
R. D. Williams, M. W. Cole and S. E. Koonin,
Phys. Rev. B28, 1076 (1983)


Nuclear physics and mathematical physics


Crumpling Transition in Dynamically Triangulated Random Surfaces
C. F. Baillie, R. D. Williams, D. A. Johnston
Nuclear Physics B 335 (2): 469-501 (1990)

Computational Aspects of Simulating Dynamically Triangulated Random Surfaces
C. F. Baillie, R. D. Williams, D. A. Johnston
Computer Physics Communications 58 (1-2): 105-117 (1990)

Semiclassical Quantization in Many Dimensions
R. D. Williams,
Ph.D. Thesis, California Institute of Technology, 1983

Atomic Final-State Interactions in Tritium Decay
R. D. Williams and S. E. Koonin,
Phys. Rev. C27, 1815 (1983) PDF

Semiclassical Quantization of the Shell Model
R. D. Williams and S. E. Koonin,
Nucl. Phys. A391, 79 (1982)

Direct Capture Cross Sections at Low Energy
R. D. Williams and S. E. Koonin,
Phys. Rev. C23, 2773 (1981) PDF