scholarly journals Enabling particle applications for exascale computing platforms

Author(s):  
Susan M Mniszewski ◽  
James Belak ◽  
Jean-Luc Fattebert ◽  
Christian FA Negre ◽  
Stuart R Slattery ◽  
...  

The Exascale Computing Project (ECP) is invested in co-design to assure that key applications are ready for exascale computing. Within ECP, the Co-design Center for Particle Applications (CoPA) is addressing challenges faced by particle-based applications across four “sub-motifs”: short-range particle–particle interactions (e.g., those which often dominate molecular dynamics (MD) and smoothed particle hydrodynamics (SPH) methods), long-range particle–particle interactions (e.g., electrostatic MD and gravitational N-body), particle-in-cell (PIC) methods, and linear-scaling electronic structure and quantum molecular dynamics (QMD) algorithms. Our crosscutting co-designed technologies fall into two categories: proxy applications (or “apps”) and libraries. Proxy apps are vehicles used to evaluate the viability of incorporating various types of algorithms, data structures, and architecture-specific optimizations and the associated trade-offs; examples include ExaMiniMD, CabanaMD, CabanaPIC, and ExaSP2. Libraries are modular instantiations that multiple applications can utilize or be built upon; CoPA has developed the Cabana particle library, PROGRESS/BML libraries for QMD, and the SWFFT and fftMPI parallel FFT libraries. Success is measured by identifiable “lessons learned” that are translated either directly into parent production application codes or into libraries, with demonstrated performance and/or productivity improvement. The libraries and their use in CoPA’s ECP application partner codes are also addressed.

Public Voices ◽  
2016 ◽  
Vol 14 (1) ◽  
pp. 115
Author(s):  
Mary Coleman

The author of this article argues that the two-decades-long litigation struggle was necessary to push the political actors in Mississippi into a more virtuous than vicious legal/political negotiation. The second and related argument, however, is that neither the 1992 United States Supreme Court decision in Fordice nor the negotiation provided an adequate riposte to plaintiffs’ claims. The author shows that their chief counsel for the first phase of the litigation wanted equality of opportunity for historically black colleges and universities (HBCUs), as did the plaintiffs. In the course of explicating the role of a legal grass-roots humanitarian, Coleman suggests lessons learned and trade-offs from that case/negotiation, describing the tradeoffs as part of the political vestiges of legal racism in black public higher education and the need to move HBCUs to a higher level of opportunity at a critical juncture in the life of tuition-dependent colleges and universities in the United States. Throughout the essay the following questions pose themselves: In thinking about the Road to Fordice and to political settlement, would the Justice Department lawyers and the plaintiffs’ lawyers connect at the point of their shared strength? Would the timing of the settlement benefit the plaintiffs and/or the State? Could plaintiffs’ lawyers hold together for the length of the case and move each piece of the case forward in a winning strategy? Who were plaintiffs’ opponents and what was their strategy? With these questions in mind, the author offers an analysis of how the campaign— political/legal arguments and political/legal remedies to remove the vestiges of de jure segregation in higher education—unfolded in Mississippi, with special emphasis on the initiating lawyer in Ayers v. Waller and Fordice, Isaiah Madison


BMJ Open ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. e049734
Author(s):  
Katya Galactionova ◽  
Maitreyi Sahu ◽  
Samuel Paul Gideon ◽  
Saravanakumar Puthupalayam Kaliappan ◽  
Chloe Morozoff ◽  
...  

ObjectiveTo present a costing study integrated within the DeWorm3 multi-country field trial of community-wide mass drug administration (cMDA) for elimination of soil-transmitted helminths.DesignTailored data collection instruments covering resource use, expenditure and operational details were developed for each site. These were populated alongside field activities by on-site staff. Data quality control and validation processes were established. Programmed routines were used to clean, standardise and analyse data to derive costs of cMDA and supportive activities.SettingField site and collaborating research institutions.Primary and secondary outcome measuresA strategy for costing interventions in parallel with field activities was discussed. Interim estimates of cMDA costs obtained with the strategy were presented for one of the trial sites.ResultsThe study demonstrated that it was both feasible and advantageous to collect data alongside field activities. Practical decisions on implementing the strategy and the trade-offs involved varied by site; trialists and local partners were key to tailoring data collection to the technical and operational realities in the field. The strategy capitalised on the established processes for routine financial reporting at sites, benefitted from high recall and gathered operational insight that facilitated interpretation of the estimates derived. The methodology produced granular costs that aligned with the literature and allowed exploration of relevant scenarios. In the first year of the trial, net of drugs, the incremental financial cost of extending deworming of school-aged children to the whole community in India site averaged US$1.14 (USD, 2018) per person per round. A hypothesised at-scale routine implementation scenario yielded a much lower estimate of US$0.11 per person treated per round.ConclusionsWe showed that costing interventions alongside field activities offers unique opportunities for collecting rich data to inform policy toward optimising health interventions and for facilitating transfer of economic evidence from the field to the programme.Trial registration numberNCT03014167; Pre-results.


2020 ◽  
pp. 1-24
Author(s):  
Jona Razzaque ◽  
Claire Lester

Abstract Sites of ancient woodland in the United Kingdom (UK) are diminishing rapidly and the multifunctional forest management system with its fragmented approach fails effectively to protect such woodland. In the face of reports on the destruction of ancient woodland, the HS2 High-Speed train project in the UK signifies the extent of trade-offs among the key stakeholders. Such large infrastructure projects typically come with high environmental and social costs, including deforestation, habitat fragmentation, biodiversity loss, and social disruption. This article examines the protection of ancient woodland in the UK and assesses the challenges in applying the ecosystem approach, an internationally recognized sustainability strategy, in the context of such protection. A better understanding of the ecosystem approach to manage ancient woodland is critical for promoting sustainable forestry practices in the UK and informs the discussion in this article of the importance of conserving ancient woodland globally. Lessons learned from UK woodland policies and certification schemes include the need to have in place strong regulatory frameworks, introduce clear indicators, and recognize pluralistic value systems alongside economic considerations. The article concludes that the protection of ancient woodland in the UK requires distinct and strong laws that reflect multiple values of this resource, acknowledge the trade-offs among stakeholders, and adopt an inclusive approach to reduce power asymmetries.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Hua Shu ◽  
Jiangtao Li ◽  
Yucheng Tu ◽  
Junjian Ye ◽  
Junyue Wang ◽  
...  

AbstractThe sound velocities of water in the Hugoniot states are investigated by laser shock compression of precompressed water in a diamond anvil cell. The obtained sound velocities in the off-Hugoniot region of liquid water at precompressed conditions are used to test the predictions of quantum molecular dynamics (QMD) simulations and the SESAME equation-of-state (EOS) library. It is found that the prediction of QMD simulations agrees with the experimental data while the prediction of SESAME EOS library underestimates the sound velocities probably due to its improper accounting for the ionization processes.


2016 ◽  
Vol 152 (6) ◽  
pp. 720
Author(s):  
Jaehwan Kim ◽  
Dong Joo Kim ◽  
Francesca S. Ortenzio ◽  
Lynn Dare ◽  
Christine Frank ◽  
...  

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