4.45 Pflops Astrophysical N-Body Simulation on K computer -- The Gravitational Trillion-Body Problem

As an entry for the 2012 Gordon-Bell performance prize, we report performance results of astrophysical N-body simulations of one trillion particles performed on the full system of K computer. This is the first gravitational trillion-body simulation in the world. We describe the scientific motivation, the numerical algorithm, the parallelization strategy, and the performance analysis. Unlike many previous Gordon-Bell prize winners that used the tree algorithm for astrophysical N-body simulations, we used the hybrid TreePM method, for similar level of accuracy in which the short-range force is calculated by the tree algorithm, and the long-range force is solved by the particle-mesh algorithm. We developed a highly-tuned gravity kernel for short-range forces, and a novel communication algorithm for long-range forces. The average performance on 24576 and 82944 nodes of K computer are 1.53 and 4.45 Pflops, which correspond to 49% and 42% of the peak speed.Comment: 10 pages, 6 figures, Proceedings of Supercomputing 2012 (http://sc12.supercomputing.org/), Gordon Bell Prize Winner. Additional information is http://www.ccs.tsukuba.ac.jp/CCS/eng/gbp201

Progress Towards Petascale Applications in Biology: Status in 2006

Petascale computing is currently a common topic of discussion in the high performance computing community. Biological applications, particularly protein folding, are often given as examples of the need for petascale computing. There are at present biological applications that scale to execution rates of approximately 55 teraflops on a special-purpose supercomputer and 2.2 teraflops on a general-purpose supercomputer. In comparison, Qbox, a molecular dynamics code used to model metals, has an achieved performance of 207.3 teraflops. It may be useful to increase the extent to which operation rates and total calculations are reported in discussion of biological applications, and use total operations (integer and floating point combined) rather than (or in addition to) floating point operations as the unit of measure. Increased reporting of such metrics will enable better tracking of progress as the research community strives for the insights that will be enabled by petascale computing.This research was supported in part by the Indiana Genomics Initiative and the Indiana Metabolomics and Cytomics Initiative. The Indiana Genomics Initiative of Indiana University and the Indiana Metabolomics and Cytomics Initiative of Indiana University are supported in part by Lilly Endowment, Inc. The authors also wish to thank IBM, Inc. for support via Shared University Research Grants and partnerships via IU’s relationship as an IBM Life Sciences Institute of Innovation. Indiana University also thanks the TeraGrid partners; IU’s participation in the TeraGrid is funded by National Science Foundation grant numbers 0338618, 0504075, and 0451237. The early development of this paper was supported by a Fulbright Senior Scholars award from the Council for International Exchange of Scholars (CIES) and the United States Department of State to Dr. Craig A. Stewart; Matthias Mueller and the Technische Universität Dresden were hosts. Many reviewers contributed to the improvement of the ideas expressed in this paper and are gratefully appreciated; Thom Dunning, Robert Germain, Chris Mueller, Jim Phillips, Richard Repasky, Ralph Roskies, and Allan Snavely are thanked particularly for their insights

Dynamic contests

Considering several main types of dynamic contests (the race, the tug-of-war, elimination contests and iterated incumbency fights) we identify a common pattern: the discouragement effect. This effect explains why the sum of rentseeking efforts often falls considerably short of the prize that is at stake. It may cause violent conflict in early rounds, but may also lead to long periods of peaceful interaction. -- Unter Berücksichtigung verschiedener Haupttypen dynamischer Wettbewerbe (das Wettrennen, das Tauziehen, Ausscheidungskämpfe und wiederholte Kämpfe um Amtszeiten) identifizieren die Autoren ein gemeinsames Muster: den Entmutigungseffekt. Dieser Effekt erklärt, wieso die Rent-seeking-Bemühungen in Summe oft deutlich nicht an den auf dem Spiel stehenden Preis heranreichen. Der Effekt kann heftige Kämpfe in den ersten Runden des Wettbewerbs auslösen, aber auch zu langen Perioden friedlichen Zusammenspiels führen.

Where do Innovations Come From? Transformations in the U.S. Economy, 1970-2006

This article brings to bear new data on the issue of structuring national innovation systems. Drawing on a unique data set of prize winning innovations between 1971 and 2006, we document three key changes in the U.S. economy. The first is an expanding role of interorganizational collaborations in producing award winning innovations. The second is the diminishing role of the largest corporations as sources of innovation. The third is the expanded role of public institutions and public funding in the innovation process. This leads us to the surprising conclusion that the U.S. increasingly resembles a Developmental Network State in which government initiatives are critical in overcoming network failures and in providing critical funding for the innovation process. The paper concludes by addressing the implications of these finding for debates over the appropriate regime for intellectual property rights.

The Equivalence of Contests

We use a Tullock-type contest model to show that intuitively and structurally different contests can be strategically and revenue equivalent to each other. We consider a two-player contest, where outcome-contingent payoffs are linear functions of prizes, own effort, and the effort of the rival. We identify strategically equivalent contests that generate the same family of best response functions and, as a result, the same revenue. However, two strategically equivalent contests may yield different equilibrium payoffs. Finally, we discuss possible contest design applications and avenues for future theoretical and empirical research.rent-seeking, contest, spillover, equivalence, revenue equivalence, contest design

The 30th Anniversary of the Supercomputing Conference: Bringing the Future Closer - Supercomputing History and the Immortality of Now

A panel of experts discusses historical reflections on the past 30 years of the Supercomputing (SC) conference, its leading role for the professional community and some exciting future challenges

King of the Hill Positional Dynamics in Contests

In a contest with positional dynamics between an incumbent and a challenger i) inequality of power may magnify conflicts, ii) more severe conflicts can go together with lower turnover of incumbents, and iii) power can be self defeating as cost advantages can reduce pay-offs. These three propositions of our paper are contrary to the implications of static conflict models. They follow from incorporating positional dynamics into the standard static approach. Such positional dynamics are relevant for competition in battlefields, politics, and market places.Contests;political stability;war;incumbency advantage

KSU Wind Ensemble

Enjoy a performance by the KSU Wind Ensemble under the direction of Dr. David Kehler from the comfort of your own home, via ArtsKSU Virtual.https://digitalcommons.kennesaw.edu/musicprograms/2375/thumbnail.jp

Kennesaw State University Wind Ensemble

The KSU Wind Ensemble, under the direction of Dr. David Kehler, presents a virtual concert of chamber and solo works, featuring students of the ensemble. Presented virtually from Morgan Concert Hall of the Bailey Performance Center.https://digitalcommons.kennesaw.edu/musicprograms/2320/thumbnail.jp

Kennesaw State University Wind Ensemble

The KSU Wind Ensemble presents a concert featuring student chamber groups and soloists from the Tuba/Euphonium, Percussion, Saxophone, Clarinet, and Horn studios. Presented virtually from Morgan Concert Hall of the Bailey Performance Center.https://digitalcommons.kennesaw.edu/musicprograms/2340/thumbnail.jp