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ECSS in the eXtreme [article]

William O'Mullane, John Hoar, Uwe Lammers
2007 arXiv   pre-print
The right figure appears later in the same paper. last ADASS (O'Mullane et al. 2007 ).  ...  The author conducted a survey over one year of many large science developments O'Mullane 2005.  ... 
arXiv:0712.0249v1 fatcat:qb2p3csey5dmrfbowpytzbzroq

It Challenges Of Gaia'S Astrometric Global Iterative Solution

Jose Luis Hernandez-Munoz, William O'Mullane
2015 Zenodo  
IT | William O'Mullane | 25/11/2015 | 13/20European Space Agency Gaia AGIS IT | William O'Mullane | 25/11/2015 | 15/20European Space Agency Gaia AGIS IT | William O'Mullane | 25/11/2015 | 17/  ...  O'Mullane | 25/11/2015 | 5/20European Space Agency t obs n t obs 1 Gaia AGIS IT | William O'Mullane | 25/11/2015 | 6/20 European Space Agency Gaia AGIS IT | William O'Mullane | 25/11/2015 |  ... 
doi:10.5281/zenodo.34577 fatcat:7klykuijdbc5zhfqcapitj2qu4

When Database Systems Meet the Grid [article]

Maria A. Nieto-Santisteban, Alexander S. Szalay, Aniruddha R. Thakar, William J. O'Mullane, Jim Gray, James Annis
2005 arXiv   pre-print
(http://casjobs.sdss.org/casjobs), substitute MySkyServerDr1.dbo for your target database (e.g: dr1, dr2, or dr3) If you have MyDB or Interface problems please contact Nolan Li <nli@pha.jhu.edu>, Wil O'Mullane  ... 
arXiv:cs/0502018v1 fatcat:52xi4nfh3rf2ri33ubutnnosey

COTS software in science operations, is it worth it? [article]

William O'Mullane and Nana Bach and Jose Hernandez and Alexander Hutton and Rosario Messineo
2016 arXiv   pre-print
O'Mullane, Bach GTS Cost For Aspera we have a mix of licenses and development: • Aspera licenses and support to date e158K • DTSTool, customisation, automation etc. .. effort ≈ 3.5 person years incl.  ... 
arXiv:1701.06484v1 fatcat:jv52rkb6d5c7vl5t7fygys4nlq

The Past, Present and Future of Astronomical Data Formats [article]

Jessica Mink, Robert G. Mann, Robert Hanisch, Arnold Rots, Rob Seaman, Tim Jenness, Brian Thomas, William O'Mullane
2014 arXiv   pre-print
Thanks to Will O'Mullane for keeping us all on time so that everyone who wanted to got to contribute and to Bob Mann for taking very good notes on the discussion.  ... 
arXiv:1411.0996v1 fatcat:zgc2p2p6gne3bb6r5uhhi7ipwm

Astronomy and Computing: a New Journal for the Astronomical Computing Community [article]

Alberto Accomazzi, Tamás Budavári, Christopher Fluke, Norman Gray, Robert G Mann, William O'Mullane, Andreas Wicenec, Michael Wise
2012 arXiv   pre-print
O'Mullane), andreas.wicenec@uwa.edu.au (Andreas Wicenec), wise@astron.nl (Michael Wise) The range of topics to appear will be mirrored by the range of people writing and reading the papers.  ...  Alberto Accomazzi), tamas.budavari@jhu.edu (Tamás Budavári), cfluke@astro.swin.edu.au (Christopher Fluke), norman@astro.gla.ac.uk (Norman Gray), rgm@roe.ac.uk (Robert G Mann), womullan@sciops.esa.int (William  ... 
arXiv:1210.8030v1 fatcat:p4zjm2sqwbbl5h6gbsinqipw4i

A Need for Dedicated Outreach Expertise and Online Programming: Astro2020 Science White Paper [article]

Amanda E Bauer, Britt Lundgren, William O'Mullane, Lauren Corlies, Megan E Schwamb, Brian Nord, Dara J Norman
2019 arXiv   pre-print
Maximizing the public impact of astronomy projects in the next decade requires NSF-funded centers to support the development of online, mobile-friendly outreach and education activities. EPO teams with astronomy, education, and web development expertise should be in place to build accessible programs at scale and support astronomers doing outreach.
arXiv:1910.14088v1 fatcat:mueillch25cobiwrpef7dnnavi

Optimising the Gaia scanning law for relativity experiments

Jos de Bruijne, Hassan Siddiqui, Uwe Lammers, John Hoar, William O'Mullane, Timo Prusti
2009 Proceedings of the International Astronomical Union  
AbstractGaia is ESA's upcoming astrometry mission, building on the heritage of its predecessor, Hipparcos. The Gaia nominal scanning law (NSL) prescribes the ideal attitude of the spacecraft over the operational phase of the mission. As such, it precisely determines when certain areas of the sky are observed. From theoretical considerations on sky-sampling uniformity, it is easy to show that the optimum scanning law for a space astrometry experiment like Gaia is a revolving scan with uniform
more » ... ation around the instrument symmetry axis. Since thermal stability requirements for Gaia's payload require the solar aspect angle to be fixed, the optimum parallax resolving power is obtained by letting the spin axis precess around the solar direction. The precession speed has been selected as compromise, limiting the across-scan smearing of images when they transit the focal plane, providing sufficient overlap between successive "great-circle" scans of the fields of view, and guaranteeing overlap of successive precession loops. With this scanning law, with fixed solar-aspect angle, spin rate, and precession speed, only two free parameters remain: the initial spin phase and the initial precession angle, at the start of science operations. Both angles, and in particular the initial precession angle, can be initialized following various (programmatic) criteria. Examples are optimization/fine-tuning of the Earth-pointing angle, of the number and total duration of Galactic-plane scans, or of the ground-station scheduling. This paper explores various criteria, with particular emphasis on the opportunity to optimise the scanning-law initial conditions to "observe" the most favorable passages of bright stars very close to Jupiter's limb. This would allow a unique determination of the light deflection due to the quadrupole component of the gravitational field of this planet.
doi:10.1017/s1743921309990597 fatcat:ht4cm563lnagljnf2m3wvrhv4y

GAVIP: A Platform for Gaia Data Analysis [article]

Daniel Vagg, Derek O'Callaghan, Fionn Ó hÓgáin, Sheila McBreen, Lorraine Hanlon, David Lynn, William O'Mullane
2016 arXiv   pre-print
Gaia is a major European Space Agency (ESA) astrophysics mission designed to map and analyse 10^9 stars, ultimately generating more than 1 PetaByte of data products. As Gaia data becomes publicly available and reaches a wider audience, there is an increasing need to facilitate the further use of Gaia products without needing to download large datasets. The Gaia Added Value Interface Platform (GAVIP) is designed to address this challenge by providing an innovative platform within which
more » ... can submit and deploy code, packaged as "Added Value Interfaces" (AVIs), which will be executed close to the data. Deployed AVIs and associated outputs may also be made available to other GAVIP platform users, thus providing a mechanism for scientific experiment reproducibility. This paper describes the capabilities and features of GAVIP.
arXiv:1605.09287v1 fatcat:qhwqooav4rcw5apdjrarj3juji

There Goes the Neighborhood: Relational Algebra for Spatial Data Search [article]

Jim Gray, Alexander S. Szalay, Aniruddha R. Thakar, Gyorgy Fekete, William O'Mullane, Maria A. Nieto-Santisteban, Gerd Heber, Arnold H. Rots
2004 arXiv   pre-print
We explored ways of doing spatial search within a relational database: (1) hierarchical triangular mesh (a tessellation of the sphere), (2) a zoned bucketing system, and (3) representing areas as disjunctive-normal form constraints. Each of these approaches has merits. They all allow efficient point-in-region queries. A relational representation for regions allows Boolean operations among them and allows quick tests for point-in-region, regions-containing-point, and region-overlap. The speed of
more » ... these algorithms is much improved by a zone and multi-scale zone-pyramid scheme. The approach has the virtue that the zone mechanism works well on B-Trees native to all SQL systems and integrates naturally with current query optimizers - rather than requiring a new spatial access method and concomitant query optimizer extensions. Over the last 5 years, we have used these techniques extensively in our work on SkyServer.sdss.org, and SkyQuery.net.
arXiv:cs/0408031v1 fatcat:dwodaxl6u5dxjprafds4t2kygq

Extending the SDSS Batch Query System to the National Virtual Observatory Grid [article]

Maria A. Nieto-Santisteban, William O'Mullane, Jim Gray, Nolan Li, Tamas Budavari, Alexander S. Szalay, Aniruddha R. Thakar
2004 arXiv   pre-print
The Sloan Digital Sky Survey science database is approaching 2TB. While the vast majority of queries normally execute in seconds or minutes, this interactive execution time can be disproportionately increased by a small fraction of queries that take hours or days to run; either because they require non-index scans of the largest tables or because they request very large result sets. In response to this, we added a multi-queue job submission and tracking system. The transfer of very large result
more » ... sets from queries over the network is another serious problem. Statistics suggested that much of this data transfer is unnecessary; users would prefer to store results locally in order to allow further cross matching and filtering. To allow local analysis, we implemented a system that gives users their own personal database (MyDB) at the portal site. Users may transfer data to their MyDB, and then perform further analysis before extracting it to their own machine. We intend to extend the MyDB and asynchronous query ideas to multiple NVO nodes. This implies development, in a distributed manner, of several features, which have been demonstrated for a single node in the SDSS Batch Query System (CasJobs). The generalization of asynchronous queries necessitates some form of MyDB storage as well as workflow tracking services on each node and coordination strategies among nodes.
arXiv:cs/0403017v1 fatcat:cfv4x7opufacdcqypvjlprjdwm

The demise of the filesystem and multi level service architecture [article]

William O'Mullane, Niall Gaffney, Frossie Economou, Arfon M. Smith, J. Ross Thomson, Tim Jenness
2019 arXiv   pre-print
Many astronomy data centres still work on filesystems. Industry has moved on; current practice in computing infrastructure is to achieve Big Data scalability using object stores rather than POSIX file systems. This presents us with opportunities for portability and reuse of software underlying processing and archive systems but it also causes problems for legacy implementations in current data centers.
arXiv:1907.13060v2 fatcat:44idxf3i7jc6bl2vdrawppm2ry

Astronomy and Computing: A new journal for the astronomical computing community

Alberto Accomazzi, Tamás Budavári, Christopher Fluke, Norman Gray, Robert G. Mann, William O'Mullane, Andreas Wicenec, Michael Wise
2013 Astronomy and Computing  
O'Mullane), andreas.wicenec@uwa.edu.au (A. Wicenec), wise@astron.nl (M.  ... 
doi:10.1016/j.ascom.2012.10.001 fatcat:yxx7tz747zdgdmvr7l264ymmly

IVOA Recommendation: IVOA Astronomical Data Query Language Version 2.00 [article]

Inaki Ortiz, Jeff Lusted, Pat Dowler, Alexander Szalay, Yuji Shirasaki, Maria A. Nieto-Santisteban, Masatoshi Ohishi, William O'Mullane, Pedro Osuna, the VOQL-TEG Working Group, the VOQL Working Group
2011 arXiv   pre-print
This document describes the Astronomical Data Query Language (ADQL). ADQL has been developed based on SQL92. This document describes the subset of the SQL grammar supported by ADQL. Special restrictions and extensions to SQL92 have been defined in order to support generic and astronomy specific operations.
arXiv:1110.0503v1 fatcat:dzvuz63pfvddrlgovlrnmjrrbe

Implementing the Gaia Astrometric Global Iterative Solution (AGIS) in Java

William O'Mullane, Uwe Lammers, Lennart Lindegren, Jose Hernandez, David Hobbs
2011 Experimental astronomy (Print)  
This paper provides a description of the Java software framework which has been constructed to run the Astrometric Global Iterative Solution for the Gaia mission. This is the mathematical framework to provide the rigid reference frame for Gaia observations from the Gaia data itself. This process makes Gaia a self calibrated, and input catalogue independent, mission. The framework is highly distributed typically running on a cluster of machines with a database back end. All code is written in
more » ... Java language. We describe the overall architecture and some of the details of the implementation.
doi:10.1007/s10686-011-9248-z fatcat:qsozpaiyezb27a36npu7ikb4ny
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