Zheng L.,University of South Florida |
Weisberg R.H.,University of South Florida |
Huang Y.,University of South Florida |
Luettich R.A.,University of North Carolina at Chapel Hill |
And 5 more authors.
Journal of Geophysical Research: Oceans | Year: 2013
We apply the Finite Volume Coastal Ocean Model to simulate the Hurricane Ike storm surge using two-dimensional (2-D) and three-dimensional (3-D) formulations. The high resolution, unstructured grid extends over the Gulf of Mexico with open boundaries in the Straits of Florida and the Yucatan Channel. With the same wind and pressure forcing, the bottom drag coefficients for the baseline 2-D and 3-D simulations are determined by spatially varying Manning coefficients and constant bottom roughness, respectively. The baseline 2-D model simulates both the forerunner and the surge, whereas the baseline 3-D model simulates the surge, but underestimates the forerunner. Increasing the minimum Manning coefficient reduces the 2-D forerunner and the surge. Manning coefficient and bottom roughness parameterizations produce different bottom drag coefficients. Using the same bottom drag coefficient, the 2-D simulation yields a smaller surge than in three dimensions. This is investigated for scenarios of either constant or variable bottom roughness where the bottom roughness is determined through Manning coefficient transformation. These sensitivity studies indicate that storm surges, simulated either in two dimensions or three dimensions, depend critically upon the parameterizations and the parameter values used for specifying bottom stress (and similar may be said of surface stress). Given suitable calibration, 2-D and 3-D models may adequately simulate storm surge. However, it is unclear that a calibration for a given storm and location may apply generally. Hence additional experimental guidance is required on the parameterizations and the parameter values used for both the surface and bottom stresses under severe wind conditions. ©2013. American Geophysical Union. All Rights Reserved.
Luettich R.A.,University of North Carolina at Chapel Hill |
Wright L.D.,Southeastern Universities Research Association |
Signell R.,U.S. Geological Survey |
Friedrichs C.,Virginia Institute of Marine Science |
And 8 more authors.
Journal of Geophysical Research: Oceans | Year: 2013
Strong and strategic collaborations among experts from academia, federal operational centers, and industry have been forged to create a U.S. IOOS Coastal and Ocean Modeling Testbed (COMT). The COMT mission is to accelerate the transition of scientific and technical advances from the coastal and ocean modeling research community to improved operational ocean products and services. This is achieved via the evaluation of existing technology or the development of new technology depending on the status of technology within the research community. The initial phase of the COMT has addressed three coastal and ocean prediction challenges of great societal importance: estuarine hypoxia, shelf hypoxia, and coastal inundation. A fourth effort concentrated on providing and refining the cyberinfrastructure and cyber tools to support the modeling work and to advance interoperability and community access to the COMT archive. This paper presents an overview of the initiation of the COMT, the findings of each team and a discussion of the role of the COMT in research to operations and its interface with the coastal and ocean modeling community in general. Detailed technical results are presented in the accompanying series of 16 technical papers in this special issue. © 2013. American Geophysical Union. All Rights Reserved.
Agency: NSF | Branch: Standard Grant | Program: | Phase: | Award Amount: 42.65K | Year: 2014
This proposal from Southeastern Universities Research Association (SURA) is requesting funds for a two day workshop for faculty and administrative leaders from US Minority Serving Institutions (MSIs) who are committed to curricular reforms. The goal of this workshop is to enable MSI educators to bring computational and data-enabled science and engineering topics into undergraduate and graduate education and exchange best pedagogical practices.
Although some strides have been made in integrating the computational science competencies required in this field into the university curriculum, the pace of change has been slow resulting in a critical shortage of sufficiently qualified students at both the baccalaureate and graduate levels. The problems of integrating computational science into the curriculum are particularly acute on the campuses of minority serving institutions (MSIs). Heavy teaching loads and the lack of local resources combined with the limited number of faculty with computational science expertise significantly slows efforts to modify the curriculum. Some institutions may lack the critical mass of faculty on their campuses to support this particular curricular reform effort. This workshop will provide an opportunity for the participating institutions to tackle curriculum reform issues and planning in a focused uninterrupted environment with expert facilitation. The workshop is designed to provide the participants with the tools and information necessary to articulate a strong business case for making curriculum changes; identify the resources and services that can be leveraged; create draft plans that can be submitted to their faculty council, provost and other bodies and committees that approve curriculum; and explore implementation collaborations.
Akli L.,Southeastern Universities Research Association |
Moore S.L.,Texas Advanced Computing Center |
Rivera L.I.,University of Illinois at Urbana - Champaign |
Teller P.J.,University of Texas at El Paso
Concurrency Computation Practice and Experience | Year: 2014
To accelerate scientific discovery, the Extreme Science and Engineering Discovery Environment (XSEDE) aims to enhance researcher productivity, increase its user base, and prepare new generations of researchers to use advanced digital technologies. Accordingly, XSEDE is educating diverse populations of new users through regional workshops targeted at large populations of those traditionally underrepresented in the use of XSEDE resources. The expanded scale and scope of recent workshops provide evidence that (1) there is strong interest in leveraging advanced digital services in research and teaching at minority-serving institutions; (2) these local events are needed to reach these communities; and (3) increased collaboration is required to inculcate the use of computational methods into research and teaching at these institutions. This makes it clear that XSEDE's efforts are meaningful beyond just providing training in advanced digital services; they contribute to national goals for developing and sustaining a large and diverse STEM workforce. This paper focuses on the first of the larger workshops (held at The University of Texas at El Paso) and its impact on subsequent events. Best practices used to plan, execute, and evaluate this workshop are discussed, and the results of a professional assessment of the three workshops are presented. Copyright © 2014 John Wiley & Sons, Ltd.
Agency: NSF | Branch: Standard Grant | Program: | Phase: SPECIAL PROGRAMS IN ASTRONOMY | Award Amount: 299.38K | Year: 2011
This NSF grant will support a majority of costs not covered by program income for the 2011 Joint Annual Conference of the National Society of Black Physicists (NSBP) and the National Society of Hispanic Physicists (NSHP). Minorities are very under-represented in the sciences and particularly in the field of physics, broadly defined. The overarching goal is to increase the number of students who graduate in physics and closely related fields by providing them with an opportunity to participate in a friendly and supportive Conference environment that combines forefront research with an extensive program of professional development. We estimate six hundred participants, three hundred of whom will be students, who, because the Conference is organized by NSBP and NSHP and heavily advertised to their membership, will be predominantly minorities. The Conference will offer extensive opportunities for the attendees to network with their peers to exchange not only scientific knowledge but also the tacit knowledge needed to succeed in the profession of physics. Our target is for the Conference to take place in April 2011, in a venue that will be determined by reasonable hotel cost and proximity to a significant scientific laboratory.
Agency: NSF | Branch: Standard Grant | Program: | Phase: Accelerator Science | Award Amount: 30.00K | Year: 2015
This award will provide support for graduate and undergraduate students to participate in one of the worlds leading accelerator conferences, the 6th International Particle Accelerator Conference, to be held in Richmond VA May 3-8, 2015. This conference expects over 1300 participants from around the world, including many of the leaders in accelerator science research. There are many presentations in all major topics in accelerator science: linear and circular colliders, photon sources, electron accelerators, alternative sources, hadron accelerators, beam dynamics, instrumentation and controls, and others. In addition the conference will have sessions on technology transfer and accelerator applications applicable to a wide field of industry.
The award will be used to support, entirely or in part, approximately 35 students. They will be making presentations which will be made available on the public web page. The students will also participate in broadening representation programs: Teachers Day Program, Women in Science and the National Society of Hispanic Physicists. This program will be an excellent opportunity for young scientists to gain information and for them to interact with more experienced researchers.
Agency: NSF | Branch: Standard Grant | Program: | Phase: SPECIAL PROGRAMS IN ASTRONOMY | Award Amount: 75.00K | Year: 2012
This award supports the partnership between the National Society of Hispanic Physicists (NSHP) and the Society for the Advancement of Chicanos and Native Americans in Science (SACNAS). The aim of the partnership is to increase the presence of physics, broadly defined, at the SACNAS National Conference. This annual conference is an opportunity for a talented group of predominantly Hispanic and Native-American students to interact with students and professionals in their disciplines, to present their research results, to learn about cutting-edge research, and to attend a variety of professional development sessions. This award will support the travel of a total of approximately forty students over three years to the conference. The award will also support the attendance of four professionals per year; these will be NSHP members who participate in the NSHP sessions and judge the physics and physics-related presentations. The award is supported by the Division of Physics, the Division of Materials Research, and the Division of Astronomical Sciences.
News Article | November 17, 2016
For the third time in its history, Thomas Jefferson National Accelerator Facility is home to one of the world's 500 fastest supercomputers. The SciPhi-XVI supercomputer was just listed as a TOP500 Supercomputer Site on November 14, placing 397th on the 48th edition of the list of the world's top supercomputers. The Top500 list was announced Monday, Nov. 14, at The International Conference for High Performance Computing, Networking, Storage and Analysis, SC16, in Salt Lake City. It's announced semi-annually and is comprised of systems that are ranked according to their computation speeds as determined by the LINPACK Benchmark, which is a calculation of a linear system represented by a large double precision dense matrix. SciPhi-XVI was delivered to Jefferson Lab and installed in mid-August and was deployed on Sept. 30 with 200 nodes. An additional 64 nodes were added to the machine in late October, and the High Performance Computing group then benchmarked the machine. The SciPhi-XVI machine benchmarked at 425.8 Teraflops using 256 of its 264 nodes. The cluster's 264 nodes are comprised of the second-generation Intel® Xeon Phi™ chips, which were released in 2016 and are codenamed Knights Landing. Each node has 64 computing cores, and individual nodes within the machine are connected via the Intel® Omni-Path Architecture, which supports a 100 Gigabit/second data transfer rate between the nodes. "A special Intel distributed LINPACK benchmark software, HPL (High Performance Linpack), was used to rank the Jefferson Lab cluster, and it is based on an open source distribution with performance enhancement for Intel® Xeon Phi™ processors," said Jie Chen, a member of Jefferson Lab's High Performance Computing group. "To achieve the performance number for the SciPhi-XVI cluster, a set of HPL running parameters has to be determined through many trials. In particular, the size of the matrix representing the linear equations solved by the HPL was chosen to be 2,457,600." Jefferson Lab conducts discovery-caliber nuclear physics research in exploring the atomic nucleus and its fundamental constituents, such as protons and neutrons and these particles' building blocks: quarks and gluons. The theory of how these particles interact -- Quantum Chromodynamics, or QCD, is calculated in the form of lattice QCD, or LQCD. Scientists will use the SciPhi-XVI machine for LQCD calculations, as well as a test system for the use of the Xeon Phi™ processors for analyzing data that is generated in Jefferson Lab's experimental physics program. The Chroma code, which is used to solve LQCD on the Xeon Phi™ processor platform, will be used with an open source library of equation solvers for LQCD. The High Performance Computing group has been modernizing the freely available Chroma code, so that it will run faster and provide better results, more quickly on the new generations of hardware. "There are always challenges to bringing online state-of-the-art hardware systems. We are very proud of our staff for their hard work and dedication that made this achievement possible," said Jefferson Lab Chief Information Office, Amber Boehnlein. "This hardware achievement, together with our efforts to continually optimize the performance of our software for the newest systems, positions the laboratory to continue performing great science in high-performance computation." Jefferson Lab work on Chroma is funded through the U.S. Department of Energy Office of Science. The research is carried out in collaboration with partner institutions, such as DOE's National Energy Research Scientific Computing Center (NERSC) Exascale Science Application Program (NESAP) and the Scientific Discovery through Advanced Computing (SciDAC) program. NERSC is a DOE Office of Science User Facility at Lawrence Berkeley National Laboratory. Supercomputer computation time on SciPhi-XVI is allocated based on the recommendations of the United States Lattice Gauge Theory Computational Program (USQCD), a consortium of top LQCD theorists in the United States that spans both high-energy physics and nuclear physics. The USQCD consortium developed the QUDA code library that is used with the Chroma code. Jefferson Science Associates, LLC, a joint venture of the Southeastern Universities Research Association, Inc. and PAE, manages and operates the Thomas Jefferson National Accelerator Facility for the U.S. Department of Energy's Office of Science. DOE's Office of Science is the single largest supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time. For more information, visit science.energy.gov.
News Article | November 29, 2016
Elena Long is all spun up over the new target she's planning for research at the Thomas Jefferson National Accelerator Facility. Now, she's gotten others spun over the idea, as well, and she's been awarded the 2016 Jefferson Science Associates Postdoctoral Research Prize to make her research plans a reality. "I'm very excited: This award is going to help us build the target that we need for doing the program that I want to build," Long said. "It's a fantastic stepping stone. I'm very happy to receive this award and hopefully use it to advance our understanding of fundamental nuclear physics." "Similar to the previous eight postdoctoral prizes that have been awarded, this award will continue to help promote the career development of young researchers in our field," said Haiyan Gao, 2015-2016 chair of the Jefferson Lab Users Group Board of Directors and Henry Newson Professor at Duke University, as well as Vice Chancellor for Academic Affairs at Duke Kunshan University in China. "We were delighted with the high-quality applications we had this year, and it was never an easier job to select the final winner." Long, a postdoctoral research associate at the University of New Hampshire, was awarded $10,000 for her plans to build and test a new kind of target that will allow scientists to explore the physics of spinning nuclei. The target will be primarily composed of a special type of ammonia. The most familiar form of ammonia, found in household cleaners, is made of one atom of nitrogen for every three atoms of hydrogen, which has a single proton in its nucleus. The form of ammonia that Long will be using is deuterated ammonia, which means that the hydrogen atoms are replaced with deuterium, an isotope of hydrogen whose nucleus contains both a proton and a neutron. The nucleus of the deuterium atom is called the deuteron. "The deuteron is the simplest composite nucleus, so the simplest nucleus made up of more than one thing. We, as physicists, have spent a very long time trying to understand it, because if we can understand everything going on in the deuteron, we can build upon that for a better understanding of more complex nuclei," Long explained. For instance, one long-known fact about deuterons is that their shape changes when they have been made to spin in a certain way. Non-spinning deuterons are shaped like donuts, while spinning deuterons are shaped like peanuts. (Caveat for physicists: we're referring to "non-spinning" as the case in which the z-axis component of the spin vector is zero). This means that the deuteron's underlying structure, the proton and the neutron, changes dramatically when it's spinning. And, going a level deeper, it means that the three quarks inside the proton and the three quarks inside the neutron are interacting in different ways when the deuteron is spinning versus when it's not. Quarks and their interactions build the nuclei of all of the atoms in the universe, so by comparing the features of spinning and non-spinning deuterons, scientists can get insight into the structure of all matter. In particular, Long and her colleagues will be studying how the six quarks in the deuteron give rise to the force that binds the nucleus together (in a measurement of a quantity they refer to as b1). They will also explore the features of that force, such as how it mediates the interaction between the proton and neutron inside the deuteron. To enable the research, Long will need to build a target that can provide spinning deuterons for study. The target that she's building will feature a small sample of deuterated ammonia that will be cooled to just above absolute zero. A magnet will apply a strong magnetic field of 5-7 Tesla, about three times stronger than the magnets used for a medical MRI machine. Then, the deuterons will be zapped with microwaves and radiofrequency waves. A nuclear magnetic resonance system will measure the polarization, the number of spinning deuterons in the target, to ensure that the target reaches the goal of about 30 percent polarization. Long said the award money will be spent buying materials for the refrigerator that will be used to cool the sample and for tests confirming that the target is able to achieve 30 percent polarization. "There's so much that we can do if we can build this target," Long said. "Taking this research and moving it forward will keep me busy for quite some time to come." The JSA Postdoctoral Research Grant has been awarded annually since 2008 by the Users Group Board of Directors. In making the award, the board judged each applicant on his or her record of accomplishment in physics, proposed use of the research grant and the likelihood of further accomplishments in the Jefferson Lab research fields. The research grant is one of the funded projects of the JSA Initiatives Fund program, provided by Jefferson Science Associates to support programs, initiatives, and activities that further the scientific outreach, and promote the science, education and technology missions of Jefferson Lab and benefit the Lab user community. You can read more about the research that may be carried out with the new target in the following research proposals: Measurements of the Quasi-Elastic and Elastic Deuteron Tensor Asymmetries and The Deuteron Tensor Structure Function b1. Jefferson Science Associates, LLC, a joint venture of the Southeastern Universities Research Association, Inc. and PAE, manages and operates the Thomas Jefferson National Accelerator Facility for the U.S. Department of Energy's Office of Science. DOE's Office of Science is the single largest supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time. For more information, visit science.energy.gov.