InTheLoop | 03.10.2014
CS Staff Present Research at Year's Biggest Physics Conference
Berkeley Lab Computing Sciences researchers were well-represented at the APS March Meeting 2014. Held by the American Physical Society annually, this year's meeting took place March 3 - 7 in Denver. Andrew Canning, Alexander Kemper, and Lin Lin of the Computational Research Division (CRD) and Jack Deslippe of NERSC all presented work at the conference. Other staff coauthored papers accepted for presentation at the conference. The full list of staff and their research represented at the meeting follows.
Andrew Canning, CRD and Jack Deslippe, NERSC:
- "Plane Wave First-principles Materials Science Codes on Multicore Supercomputer Architectures"
- "Optimizing GW for Petascale HPC and Beyond."
Lin Lin and Chao Yang, CRD: "SIESTA-PEXSI: Massively parallel method for efficient and accurate ab initio materials simulation"
Alexander Kemper, CRD:
- "Ultrafast transient decoupling and multi-phonon effects in driven electron-phonon systems"
- "Interplay between accidental gap nodes and nematic order in iron-based superconductors"
- "Photo-induced topological phase transition in graphene studied by exact simulation of pump-probe photoemission spectroscopy"
Sherry Li, Slim Chourou, Abhinav Sarje, CRD: "Beyond Petascale with the HipGISAXS Software Suite"
Maciej Haranczyk: CRD, "High throughput computation of defect properties in metals."
NERSC's Sudip Dosanjh to Address IBM Zurich Research Laboratory
NERSC Director Sudip Dosanjh will give a talk at the IBM Zurich Research Laboratory on Friday, March 14. His talk will touch on the importance of extreme data science for the U.S. Department of Energy, the role of exascale computing in meeting extreme data challenges, and then explore the many ways NERSC is addressing the needs of researchers to collect, process and analyze growing data sets.
Cozzarelli Prize Goes to NERSC Planet Pipeline Scientist
Erik Petigura, who ran his Kepler planet pipeline at NERSC, was honored with a National Academy of Sciences Cozzarelli Prize for his work. Petigura and colleague Andrew Howard, now at the University of Hawaii, Manoa spent three years developing a transit search pipeline called TERRA that is optimized for finding small planets. When they used this tool on supercomputers at NERSC to analyze nearly four years of Kepler observations, the scientists determined that our galaxy could contain as many as 40 billion habitable Earth-sized planets. »Read more about Petigura's work at NERSC. »Read more about the prize.
Reminder: Upcoming SC14 Deadlines
SC14 is still months away but deadlines are already approaching:
March 31: Tutorial submissions due
April 4: Technical paper abstract submissions close
April 11: Student cluster competition proposals due
April 25: Panel submissions due
May 1: Gordon Bell Prize applications due; George Michael Memorial HPC Fellowship applications due
This Week's CS Seminars
Omnipresent Ethernet: From Concepts to Products
Wednesday, March 12, 2014, 1:00pm - 2:00pm | Bldg. 50A, Room 5132
Ashwin Gumaste, Department of Computer Science and Engineering, Indian Institute of Technology (IIT) Bombay
Omnipresent Ethernet, or OE, is a next generation carrier-class Internet architecture. OE extends Ethernet for end-to-end provisioning across the LAN, MAN and WAN, using concepts of Carrier Ethernet in conjunction with simple network architectural understanding. The advantages of OE such as low-latency, low energy, small footprint are discussed. OE working is presented especially in conjunction with some of the advances in Carrier Ethernet. Mapping OE to multiple layers of the protocol stack and some of the base problems that we have considered will also be showcased. A pragmatic 1-micro-second port-to-port supporting 96 Gbps cross-connect Carrier Ethernet Switch Router will be presented. The working, analysis and the development of this architecture is discussed. OE has led to a family of products, conceptualized, designed, prototyped at IIT Bombay and now made available through DAE's PSU the Electronics Corporation of India Ltd, ECIL (http://www.ecil.co.in/ECR/ECR.pdf). We will give an overview of these products, how these have been developed, the internal workings of the hardware and software as well as deployments in the nation's leading networks and data-centers. Some open problems will also be presented.
Multiphysics and Multiscale Modeling of Cardiac Dynamics
Friday, March 14, 2014, 11:00am - 12:00pm | Bldg. 50F, Room 1647
Boyce Griffith, Assistant Professor of Medicine and Mathematics, Leon H. Charney Division of Cardiology
The heart is a coupled electro-fluid-mechanical system. The contractions of the cardiac muscle are stimulated and coordinated by the electrophysiology of the heart; these contractions in turn affect the electrical function of the heart by altering the macroscopic conductivity of the tissue and by influencing stretch-activated transmembrane ion channels. In this talk, I will present mathematical models and adaptive numerical methods for describing cardiac mechanics, fluid dynamics, and electrophysiology, as well as applications of these models and methods to cardiac fluid-structure and electro-mechanical interaction. I will also describe novel models of cardiac electrophysiology that go beyond traditional macroscopic (tissue-scale) descriptions of cardiac electrical impulse propagation by explicitly incorporating details of the cellular microstructure into the model equations. Standard models of cardiac electrophysiology, such as the monodomain or bidomain equations, account for this cellular microstructure in only a homogenized or averaged sense, and we have demonstrated that such homogenized models yield incorrect results in certain pathophysiological parameter regimes. To obtain accurate model predictions in these parameter regimes without resorting to a fully cellular model, we have developed an adaptive multiscale model of cardiac conduction that locally deploys detailed cellular models only where needed, while employing the more efficient macroscale equations where those equations suffice.
Link of the Week: Celebrate Pi Day With a Large Pizza, or Maybe Not...
If you're celebrating Pi Day on March 14, go ahead and order that larger pizza: You've got math on your side, although the economics may not be. An NPR Planet Money report compiled 74,476 prices from 3,678 pizza places around the country and compared price vs. area to find that the larger pizza is always the better deal. "The math of why bigger pizzas are such a good deal is simple: A pizza is a circle, and the area of a circle increases with the square of the radius," the article points out (π r 2). Pizza prices rise at more restrained rates, giving you more pizza for the money. Another writer, however, counters with an economics concept: "negative marginal returns." That's the point at which more pizza makes you less happy, burdening you with carrying home leftovers, clearing fridge space, throwing out the spoiled leftovers, or, perhaps worse, making a midnight snack of them. In that context, it's a better deal to order only as much pizza as you can eat. Food for thought. Have a happy Pi Day.