Unum is a number format that is similar to IEEE 754 format (floating point numbers) that is publicly proposed by John L. Gustafson in 2013. By August 2013, he had a working unum environment to explain and justify his number system. The book "The End of Error" authored by John in 2015 elaborates his comprehensive proposal to have unums replace floating point numbers for improvement in performance and accuracy. Unum has since evolved. The original Type I provides a compact way to express interval arithmetic. Type II enables a clean mathematic design based on projective reals. The latest version, Posits and Valids, has all the advantages of the original Type I and Type II and is additionally hardware-friendly, making it a favourite among many.

NGA Team

John L. Gustafson

John L. Gustafson, the creator of unums and posits, is widely known in High Performance Computing field for his invention of Gustafson's law. He had also introduced the first commercial computer cluster and led the reconstrution of Atansoff-Berry computer. Most notably, John was a recipient of the Gorden Bell Prize in 1988, International Anasoff Award in 2006 and IEEE Computer Society Golden Core Award in 2007. John also received a prestigious internal Intel award in 2012 for Technology Strategic Long-Range Plan (TSLRP), which indicated his proposed technology, the underlying concepts of unum, possessed qualities to be a game-changer.

S.H. Leong (Cerlane)

LEONG Siew Hoon (Cerlane) received her M.Sc. degree in “Computational Science and Engineering” from Technical University of Munich (TUM) and Ph.D. in Urgent Computing on distributed HPC resources from LMU Munich. She was employed in National German HPC centre, Leibniz Supercomputing Centre, from 2007 to 2016. She participated in numerous German and European e-Infrastructure projects, including DEISA and PRACE, and led EU work- packages in VERCE and ComPAT respectively. Her main role was to serve as an ICT consultant to guide and integrate applications on distributed European HPC centres across multiple e-Infrastructures. From 2016, she joined National Supercomputing Centre, Singapore, and was seconded in July 2017 to support and conduct research together with Gustafson on the next-generation computer arithmetic (unums and posits). She acts as technical consultant to in-house and external collaborators on leveraging and implementing posit and had since contributed to the definition of posit rounding mode and quire’s (Not a Real) mode. She is the developer of the posit online widgets and the fast C library, SoftPosit. SoftPosit is the currently the fastest software library with complete support of all functionalities required in the Draft Posit Standard.

W.L. Koh (Vanessa)

Vanessa graduated with a Bachelor of Business (Events Management & Human Resource Management) from Griffith University, Brisbane Australia. She joined the team in October 2017 and has helped to coordinate the inaugural Conference of Next Generation Arithmetic (CoNGA), which was held in March 2018. Currently she supports the team administratively and also maintains the webpage of the next-generation computer arithmetic (unums and posits) and social media platforms.

NGA Working Group

Chairman: Prof. John Gustafson
A*STAR and National University of Singapore, Singapore
Dr. Peter G. Lindstorm
Lawrence Livermore National Laboratory, USA
Prof. Vassil Dimitrov
University of Calgary, Canada
Dr. Siew Hoon Leong (Cerlane)
A*STAR Singapore
Dr. Gerd Bohlender
Previously Karlsruher Institut für Technologie, Germany
Dr. Andrew Shewmaker
OpenEye Scientific Software, Inc, USA
Dr. E. Theodore L. Omtzigt
Stillwater Supercomputing, USA
Dr. Isaac Yonemoto
Sybase, USA

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