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  • richardmitnick 3:53 pm on August 1, 2014 Permalink | Reply
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    From Rutgers University: “Astrophysics Professor Creates Computer Models that Help Explain How Galaxies Formed and Evolved” 

    Rutgers Banner
    Rutgers University

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    Rachel Somerville (Photo: Miguel Acevedo)

    July 30, 2014
    Carl Blesch

    When most people think of astronomers, they envision scientists who spend time peering at stars and galaxies through telescopes on high mountain tops. Rutgers astronomer Rachel Somerville depends on colleagues who make such observations, but her primary tools for understanding how galaxies formed billions of years ago – and how they continue to evolve today – are large computers.

    The quality and significance of her work were affirmed this week when the Simons Foundation, a private foundation that sponsors research in mathematics and the basic sciences, awarded Somerville $500,000 in research support over five years. She is one of 16 theoretical scientists at American and Canadian universities who were named Simons Investigators for 2014.

    A professor of astrophysics in the Department of Physics and Astronomy, School of Arts and Sciences, Somerville creates computer models or simulations of the physical principles that underlie galaxy formation. These models help astronomers make sense of what they see when the Hubble Space Telescope and other instruments peer into the farthest reaches of space and reveal how galaxies looked as they took shape in a young universe.

    The Simons Foundation cited her contributions to the development of “semianalytic modeling methods that combine computational and pencil-and-paper theory.” According to the group, these contributions have helped scientists understand how the growth of supermassive black holes and the energy they release is linked to a galaxy’s properties and its ability to form stars.

    Somerville explains that astronomers cannot see any single galaxy evolve through a telescope.

    “We see galaxies at different points in their lifetimes and in different wavelengths,” she said, referring to images acquired with visible light, radio waves and X-rays. Models then help astronomers predict which kinds of early galaxies evolved into disks like our Milky Way while others evolved into the round balls of stars that astronomers call elliptical galaxies.

    As a theoretical astronomer, Somerville values the opportunities she gets to interact with observational astronomers at Rutgers and elsewhere who provide her with new data that make her models more comprehensive and robust.

    “It’s hard to make models that fit all the observations,” she said. “I try to go the extra distance to connect what the models predict with things that we can actually observe.”

    Somerville is a relative newcomer to Rutgers, appointed in October 2011 to the George A. and Margaret M. Downsbrough Chair in Astrophysics.

    In 2013, she received the Dannie Heineman Prize in Astrophysics from the American Astronomical Society and the American Institute of Physics. The prize recognizes exceptional work by mid-career astronomers, citing her for providing fundamental insights into galaxy formation and evolution using modeling, simulations, and observations.

    Before joining Rutgers, Somerville held a joint appointment as associate research professor at Johns Hopkins University and associate astronomer with tenure at the Space Telescope Science Institute (STScI). STScI manages selection, planning and scheduling of scientific activities for the Hubble Space Telescope.

    Before that, she held faculty appointments at the Max Planck Institute for Astronomy in Germany and the University of Michigan, and postdoctoral appointments at the Hebrew University in Jerusalem and Cambridge University in the United Kingdom.

    Somerville’s goal at Rutgers is to build more expertise in galaxy formation theory and help the department’s astronomy group pursue new areas such as the study of extrasolar planets.

    “Rutgers is a great place for galaxy formation theorists because we have opportunities to interact with the excellent observational astronomers here,” she said, noting the university’s involvement with the powerful new Southern African Large Telescope, also referred to as SALT. “I’ve benefitted from supportive colleagues and contact with graduate and undergraduate students. I’m constantly inspired by their enthusiasm.”

    South African Large Telescope
    South African Large Telescope

    Rutgers, The State University of New Jersey, is a leading national research university and the state’s preeminent, comprehensive public institution of higher education. Rutgers is dedicated to teaching that meets the highest standards of excellence; to conducting research that breaks new ground; and to providing services, solutions, and clinical care that help individuals and the local, national, and global communities where they live.

    Founded in 1766, Rutgers teaches across the full educational spectrum: preschool to precollege; undergraduate to graduate; postdoctoral fellowships to residencies; and continuing education for professional and personal advancement.

    Rutgers Seal


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  • richardmitnick 2:49 pm on February 20, 2014 Permalink | Reply
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    From Caltech: “A New Laser for a Faster Internet” 

    Caltech Logo
    Caltech

    02/19/2014
    Jessica Stoller-Conrad

    A new laser developed by a research group at Caltech holds the potential to increase by orders of magnitude the rate of data transmission in the optical-fiber network—the backbone of the Internet.

    The study was published the week of February 10–14 in the online edition of the Proceedings of the National Academy of Sciences. The work is the result of a five-year effort by researchers in the laboratory of Amnon Yariv, Martin and Eileen Summerfield Professor of Applied Physics and professor of electrical engineering; the project was led by postdoctoral scholar Christos Santis (PhD ’13) and graduate student Scott Steger.Light is capable of carrying vast amounts of information—approximately 10,000 times more bandwidth than microwaves, the earlier carrier of long-distance communications. But to utilize this potential, the laser light needs to be as spectrally pure—as close to a single frequency—as possible. The purer the tone, the more information it can carry, and for decades researchers have been trying to develop a laser that comes as close as possible to emitting just one frequency.

    laser
    No image Credit

    Today’s worldwide optical-fiber network is still powered by a laser known as the distributed-feedback semiconductor (S-DFB) laser, developed in the mid 1970s in Yariv’s research group. The S-DFB laser’s unusual longevity in optical communications stemmed from its, at the time, unparalleled spectral purity—the degree to which the light emitted matched a single frequency. The laser’s increased spectral purity directly translated into a larger information bandwidth of the laser beam and longer possible transmission distances in the optical fiber—with the result that more information could be carried farther and faster than ever before.

    At the time, this unprecedented spectral purity was a direct consequence of the incorporation of a nanoscale corrugation within the multilayered structure of the laser. The washboard-like surface acted as a sort of internal filter, discriminating against spurious “noisy” waves contaminating the ideal wave frequency. Although the old S-DFB laser had a successful 40-year run in optical communications—and was cited as the main reason for Yariv receiving the 2010 National Medal of Science—the spectral purity, or coherence, of the laser no longer satisfies the ever-increasing demand for bandwidth.

    “What became the prime motivator for our project was that the present-day laser designs—even our S-DFB laser—have an internal architecture which is unfavorable for high spectral-purity operation. This is because they allow a large and theoretically unavoidable optical noise to comingle with the coherent laser and thus degrade its spectral purity,” he says.

    The old S-DFB laser consists of continuous crystalline layers of materials called III-V semiconductors—typically gallium arsenide and indium phosphide—that convert into light the applied electrical current flowing through the structure. Once generated, the light is stored within the same material. Since III-V semiconductors are also strong light absorbers—and this absorption leads to a degradation of spectral purity—the researchers sought a different solution for the new laser.

    The high-coherence new laser still converts current to light using the III-V material, but in a fundamental departure from the S-DFB laser, it stores the light in a layer of silicon, which does not absorb light. Spatial patterning of this silicon layer—a variant of the corrugated surface of the S-DFB laser—causes the silicon to act as a light concentrator, pulling the newly generated light away from the light-absorbing III-V material and into the near absorption-free silicon.

    This newly achieved high spectral purity—a 20 times narrower range of frequencies than possible with the S-DFB laser—could be especially important for the future of fiber-optic communications. Originally, laser beams in optic fibers carried information in pulses of light; data signals were impressed on the beam by rapidly turning the laser on and off, and the resulting light pulses were carried through the optic fibers. However, to meet the increasing demand for bandwidth, communications system engineers are now adopting a new method of impressing the data on laser beams that no longer requires this “on-off” technique. This method is called coherent phase communication.

    In coherent phase communications, the data resides in small delays in the arrival time of the waves; the delays—a tiny fraction (10-16) of a second in duration—can then accurately relay the information even over thousands of miles. The digital electronic bits carrying video, data, or other information are converted at the laser into these small delays in the otherwise rock-steady light wave. But the number of possible delays, and thus the data-carrying capacity of the channel, is fundamentally limited by the degree of spectral purity of the laser beam. This purity can never be absolute—a limitation of the laws of physics—but with the new laser, Yariv and his team have tried to come as close to absolute purity as is possible.

    These findings were published in a paper titled, High-coherence semiconductor lasers based on integral high-Q resonators in hybrid Si/III-V platforms. In addition to Yariv, Santis, and Steger, other Caltech coauthors include graduate student Yaakov Vilenchik, and former graduate student Arseny Vasilyev (PhD, ’13). The work was funded by the Army Research Office, the National Science Foundation, and the Defense Advanced Research Projects Agency. The lasers were fabricated at the Kavli Nanoscience Institute at Caltech.

    See the full article here.

    The California Institute of Technology (commonly referred to as Caltech) is a private research university located in Pasadena, California, United States. Caltech has six academic divisions with strong emphases on science and engineering. Its 124-acre (50 ha) primary campus is located approximately 11 mi (18 km) northeast of downtown Los Angeles. “The mission of the California Institute of Technology is to expand human knowledge and benefit society through research integrated with education. We investigate the most challenging, fundamental problems in science and technology in a singularly collegial, interdisciplinary atmosphere, while educating outstanding students to become creative members of society.”
    Caltech buildings


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  • richardmitnick 3:13 pm on February 11, 2014 Permalink | Reply
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    From PPPL: “Solution to plasma-etching puzzle could mean more powerful microchips” 

    February 11, 2014
    John Greenwald

    Research conducted by PPPL in collaboration with the University of Alberta provides a key step toward the development of ever-more powerful computer chips. The researchers discovered the physics behind a mysterious process that gives chipmakers unprecedented control of a recent plasma-based technique for etching transistors on integrated circuits, or chips. This discovery could help to maintain Moore’s Law, which observes that the number of transistors on integrated circuits doubles nearly every two years.

    chip
    An integrated-circuit microchip with 456 million transistors
    (Photo by John Greenwald/PPPL Office of Communications)

    The recent technique utilizes electron beams to reach and harden the surface of the masks that are used for printing microchip circuits. More importantly, the beam creates a population of “suprathermal” electrons that produce the plasma chemistry necessary to protect the mask. The energy of these electrons is greater than simple thermal heating could produce — hence the name “suprathermal.” But how the beam electrons transform themselves into this suprathermal population has been a puzzle.

    The PPPL and University of Alberta researchers used a computer simulation to solve the puzzle. The simulation revealed that the electron beam generates intense plasma waves that move through the plasma like ripples in water. And these waves lead to the generation of the crucial suprathermal electrons.

    This discovery could bring still-greater control of the plasma-surface interactions and further increase the number of transistors on integrated circuits. Insights from both numerical simulations and experiments related to beam-plasma instabilities thus portend the development of new plasma sources and the increasingly advanced chips that they fabricate.

    See the full article here.

    Princeton Plasma Physics Laboratory is a U.S. Department of Energy national laboratory managed by Princeton University.


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  • richardmitnick 3:14 pm on January 15, 2014 Permalink | Reply
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    From Fermilab: “From the Scientific Computing Division – Intensity Frontier experiments develop insatiable appetite” 


    Fermilab is an enduring source of strength for the US contribution to scientific research world wide.

    rr
    Rob Roser, head of the Scientific Computing Division, wrote this column.

    The neutrino and muon experiments at Fermilab are getting more demanding! They have reached a level of sophistication and precision that the present computing resources available at Fermilab are no longer sufficient to handle. The solution: The Scientific Computing Division is now introducing grid and cloud services to satisfy those experiments’ appetite for large amounts of data and computing time.

    An insatiable appetite for computing resources is not new to Fermilab. Both Tevatron experiments as well as the CMS experiment require computing resources that far exceed our on-site capacity to successfully perform their science. As a result the scientific collaborations have been working closely with us over many years to leverage computing capabilities at the universities and other laboratories. Now, the demand from our Intensity Frontier experiments has reached this level.

    The Scientific Computing Services quadrant under the leadership of Margaret Votava has worked very hard over the past year with various computing organizations to provide experiments with the capability to run their software at remote locations, transfer data and bring the results back to Fermilab.

    See much more in the full article here.

    Fermilab Campus

    Fermi National Accelerator Laboratory (Fermilab), located just outside Batavia, Illinois, near Chicago, is a US Department of Energy national laboratory specializing in high-energy particle physics.


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  • richardmitnick 6:58 am on April 3, 2013 Permalink | Reply
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    From Symmetry: “Semiconductors” 

    Accelerator-powered ion implantation proves key to advances in integrated circuits.

    April 02, 2013
    Glenn Roberts Jr.

    Particle accelerators earned an important place on the semiconductor assembly line decades ago, and today their role in silicon wafer manufacturing processes continues to grow in complexity and scope.

    wafer
    A single silicon wafer, like the one seen here, is typically bombarded with ions of several different elements. Boron, arsenic and phosphorous are among the elements most commonly used in the semiconductor industry. Photo: Reidar Hahn, Fermilab

    As a silicon wafer makes its way down the assembly line, it may pass through dozens of particle beams produced by accelerators in a process known as ion implantation. Born out of the national labs, this process embeds fast-moving particles in the wafer at specific locations, depths and concentrations, permanently changing the semiconductor’s electrical qualities by selectively creating an abundance of electrons or electron vacancies at specific locations.

    These electron-rich or electron-depleted areas, in combination with other transistor components affixed to the regions, work like rivers of charge to guide electrons around a semiconductor in precisely controlled ways.

    Advances in ion implantation have helped manufacturers to pack more transisters into an integrated circuit, revolutionizing computing speed and power and reducing room-sized machines to pocket-sized devices.

    ‘Ion implantation is an absolutely necessary technology in the way we build devices, and its use has been growing,’ says Larry Larson, an engineering professor at Texas State University at San Marcos who previously worked for National Semiconductor, a Silicon Valley-based chip manufacturing firm acquired by Texas Instruments in 2011. ‘Every time a factory is built, they need some number of ion-implantation machines in the factory, and the number of machines per factory has grown over the years.’

    Today there are an estimated 12,000 ion-implantation accelerators operating worldwide and an average of 300 new ones are purchased each year, with the lion’s share purchased by the semiconductor industry.

    To meet manufacturing demands, the implanting processes become incrementally more exacting and elaborate each year, with researchers fine-tuning the number of particle beams a single wafer encounters and the angle at which each beam hits the wafer. The speed of the implantation process is also ramping up to meet manufacturing demand; today, the quickest implanters can process about 300 wafers an hour.

    Alexander Wu Chao, a professor at SLAC National Accelerator Laboratory and editor of the journal Reviews of Accelerator Science and Technology, says that ion-implantation accelerators are essential to today’s—and tomorrow’s—advanced electronics.”

    See the full article here.

    Symmetry is a joint Fermilab/SLAC publication.


     
  • richardmitnick 2:06 pm on March 11, 2013 Permalink | Reply
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    From Caltech: “Creating Indestructible Self-Healing Circuits” 

    Caltech Logo
    Caltech

    Caltech engineers build electronic chips that repair themselves

    03/11/2013
    Kimm Fesenmaier

    Imagine that the chips in your smart phone or computer could repair and defend themselves on the fly, recovering in microseconds from problems ranging from less-than-ideal battery power to total transistor failure. It might sound like the stuff of science fiction, but a team of engineers at the California Institute of Technology (Caltech), for the first time ever, has developed just such self-healing integrated chips.

    The team, made up of members of the High-Speed Integrated Circuits laboratory in Caltech’s Division of Engineering and Applied Science, has demonstrated this self-healing capability in tiny power amplifiers. The amplifiers are so small, in fact, that 76 of the chips—including everything they need to self-heal—could fit on a single penny. In perhaps the most dramatic of their experiments, the team destroyed various parts of their chips by zapping them multiple times with a high-power laser, and then observed as the chips automatically developed a work-around in less than a second.

    ‘It was incredible the first time the system kicked in and healed itself. It felt like we were witnessing the next step in the evolution of integrated circuits,’ says Ali Hajimiri, the Thomas G. Myers Professor of Electrical Engineering at Caltech. ‘We had literally just blasted half the amplifier and vaporized many of its components, such as transistors, and it was able to recover to nearly its ideal performance.’

    chip
    Some of the damage Caltech engineers intentionally inflicted on their self-healing power amplifier using a high-power laser. The chip was able to recover from complete transistor destruction. This image was captured with a scanning electron microscope.
    Credit: Jeff Chang and Kaushik Dasgupta

    The team’s results appear in the March issue of IEEE Transactions on Microwave Theory and Techniques.”

    See the full article here.

    The California Institute of Technology (commonly referred to as Caltech) is a private research university located in Pasadena, California, United States. Caltech has six academic divisions with strong emphases on science and engineering. Its 124-acre (50 ha) primary campus is located approximately 11 mi (18 km) northeast of downtown Los Angeles. “The mission of the California Institute of Technology is to expand human knowledge and benefit society through research integrated with education. We investigate the most challenging, fundamental problems in science and technology in a singularly collegial, interdisciplinary atmosphere, while educating outstanding students to become creative members of society.”
    Caltech buildings


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  • richardmitnick 10:14 am on February 13, 2013 Permalink | Reply
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    From ESA Technology: “Silicon brains to oversee satellites” 

    ESASpaceForEuropeBanner
    European Space Agency

    XMM Newton
    XMM-Newton

    herschelHerschel


    Planck

    13 February 2013
    No Writer Credit

    A beautiful and expensive sight: upwards of €6 million-worth of silicon wafers, crammed with the complex integrated circuits that sit at the heart of each and every ESA mission. Years of meticulous design work went into these tiny brains, empowering satellites with intelligence.

    chgips
    Silicon wafers etched with integrated circuits for space missions. No image credit.

    The image shows a collection of six silicon wafers that contain some 14 different chip designs developed by several European companies during the last eight years with ESA’s financial and technical support.

    Each of these 20 cm-diameter wafers contains between 30 and 80 replicas of each chip, each one carrying up to about 10 million transistors or basic circuit switches.

    To save money on the high cost of fabrication, various chips designed by different companies and destined for multiple ESA projects are crammed onto the same silicon wafers, etched into place at specialised semiconductor manufacturing plants or ‘fabs’, in this case LFoundry (formerly Atmel) in France.

    Once manufactured, the chips, still on the wafer, are tested. The wafers are then chopped up. They become ready for use when placed inside protective packages – just like standard terrestrial microprocessors – and undergo final quality tests.

    Through little metal pins or balls sticking out of their packages these miniature brains are then connected to other circuit elements – such as sensors, actuators, memory or power systems – used across the satellite.

    To save the time and money needed to develop complex chips like these, ESA’s Microelectronics section maintains a catalogue of chip designs, known as Intellectual Property (IP) cores, available to European industry through ESA licence.”

    See the full article here.

    The European Space Agency (ESA), established in 1975, is an intergovernmental organization dedicated to the exploration of space, currently with 19 member states. Headquartered in Paris, ESA has a staff of more than 2,000. ESA’s space flight program includes human spaceflight, mainly through the participation in the International Space Station program, the launch and operations of unmanned exploration missions to other planets and the Moon, Earth observation, science, telecommunication as well as maintaining a major spaceport, the Guiana Space Centre at Kourou, French Guiana, and designing launch vehicles. ESA science missions are based at ESTEC in Noordwijk, Netherlands, Earth Observation missions at ESRIN in Frascati, Italy, ESA Mission Control (ESOC) is in Darmstadt, Germany, the European Astronaut Centre (EAC) that trains astronauts for future missions is situated in Cologne, Germany, and the European Space Astronomy Centre is located in Villanueva de la Cañada, Spain.

    ESA Technology


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  • richardmitnick 6:12 pm on February 10, 2013 Permalink | Reply
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    From Argonne Lab: “New classes of magnetoelectric materials promise advances in computing technology” 

    News from Argonne National Laboratory

    February 7, 2013
    Jared Sagoff

    Although scientists have been aware that magnetism and electricity are two sides of the same proverbial coin for almost 150 years, researchers are still trying to find new ways to use a material’s electric behavior to influence its magnetic behavior, or vice versa.

    star
    An illustration of a titanium-europium oxide cage lattice studied in the experiment.Image by Renee Carlson.

    Thanks to new research by an international team of researchers led by the U.S. Department of Energy’s Argonne National Laboratory, physicists have developed new methods for controlling magnetic order in a particular class of materials known as “magnetoelectrics.”

    Magnetoelectrics get their name from the fact that their magnetic and electric properties are coupled to each other. Because this physical link potentially allows control of their magnetic behavior with an electrical signal or vice versa, scientists have taken a special interest in magnetoelectric materials.

    ‘Electricity and magnetism are intrinsically coupled – they’re the same entity,’ said Philip Ryan, a physicist at Argonne’s Advanced Photon Source. ‘Our research is designed to accentuate the coupling between the electric and magnetic parameters by subtly altering the structure of the material.

    This new approach to cross-coupling magnetoelectricity could prove a key step toward the development of next-generation memory storage, improved magnetic field sensors, and many other applications long dreamed about. Unfortunately, scientists still have a ways to go to translating these findings into commercial devices.’

    ‘Instead of having just a ‘0’ or a ‘1,’ you could have a broader range of different values,’ Ryan said. ‘A lot of people are looking into what that kind of logic would look like.’

    A paper based on the research, “Reversible control of magnetic interactions by electric field in a single-phase material,” was published in Nature Communications. “

    See the full article here.

    Argonne Lab Campus

    Argonne is managed by UChicago Argonne, LLC for the U.S. Department of Energy’s Office of Science


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  • richardmitnick 7:32 pm on January 29, 2013 Permalink | Reply
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    From Stanford University: “Stanford Researchers Break Million-core Supercomputer Barrier” 

    Stanford Engineering plate

    Researchers at the Center for Turbulence Research set a new record in supercomputing, harnessing a million computing cores to model supersonic jet noise. Work was performed on the newly installed Sequoia IBM Bluegene/Q system at Lawrence Livermore National Laboratories.

    Friday, January 25, 2013
    Andrew Myers

    Stanford Engineering’s Center for Turbulence Research (CTR) has set a new record in computational science by successfully using a supercomputer with more than one million computing cores to solve a complex fluid dynamics problem—the prediction of noise generated by a supersonic jet engine.

    Joseph Nichols, a research associate in the center, worked on the newly installed Sequoia IBM Bluegene/Q system at Lawrence Livermore National Laboratories (LLNL) funded by the Advanced Simulation and Computing (ASC) Program of the National Nuclear Security Administration (NNSA). Sequoia once topped list of the world’s most powerful supercomputers, boasting 1,572,864 compute cores (processors) and 1.6 petabytes of memory connected by a high-speed five-dimensional torus interconnect.

    seq
    A floor view of the newly installed Sequoia supercomputer at the Lawrence Livermore National Laboratories. (Photo: Courtesy of Lawrence Livermore National Laboratories)

    Because of Sequoia’s impressive numbers of cores, Nichols was able to show for the first time that million-core fluid dynamics simulations are possible—and also to contribute to research aimed at designing quieter aircraft engines.

    jet
    An image from the jet noise simulation. A new design for an engine nozzle is shown in gray at left. Exhaust tempertures are in red/orange. The sound field is blue/cyan. Chevrons along the nozzle rim enhance turbulent mixing to reduce noise. (Illustration: Courtesy of the Center for Turbulence Research, Stanford University)

    Andrew Myers is associate director of communications for the Stanford University School of Engineering.”

    See the full article here.

    Leland and Jane Stanford founded the University to “promote the public welfare by exercising an influence on behalf of humanity and civilization.” Stanford opened its doors in 1891, and more than a century later, it remains dedicated to finding solutions to the great challenges of the day and to preparing our students for leadership in today’s complex world. Stanford, is an American private research university located in Stanford, California on an 8,180-acre (3,310 ha) campus near Palo Alto. Since 1952, more than 54 Stanford faculty, staff, and alumni have won the Nobel Prize, including 19 current faculty members

     
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