Transformative Science for the Next Decade with the Green Bank Observatory
NASA Astrophysics Data System (ADS)
O'Neil, Karen; Frayer, David; Ghigo, Frank; Lockman, Felix; Lynch, Ryan; Maddalena, Ronald; minter, Anthony; Prestage, Richard
2018-01-01
With new instruments and improved performance, the 100m Green Bank Telescope is now demonstrating its full potential. On this 60th anniversary of the groundbreaking for the Green Bank Observatory, we can look forward to the future of the facility for the next 5, 10, and even 20 years. Here we describe the results from a recent workshop, “Transformative Science for the Next Decade with the Green Bank Observatory: Big Questions, Large Programs, and New Instruments,” and describe the scientific plans for our facility.
47 CFR 25.203 - Choice of sites and frequencies.
Code of Federal Regulations, 2014 CFR
2014-10-01
... National Radio Astronomy Observatory: In order to minimize possible harmful interference at the National Radio Astronomy Observatory site at Green Bank, Pocahontas County, W. Va., and at the Naval Radio..., simultaneously notify the Director, National Radio Astronomy Observatory, P.O. Box No. 2, Green Bank, W. Va...
New Book Recounts Exciting, Colorful History Of Radio Astronomy in Green Bank, West Virginia
NASA Astrophysics Data System (ADS)
2007-07-01
A new book published by the National Radio Astronomy Observatory (NRAO) tells the story of the founding and early years of the Observatory at Green Bank, West Virginia. But it was Fun: the first forty years of radio astronomy at Green Bank, is not a formal history, but rather a scrapbook of early memos, recollections, anecdotes and reports. But it was Fun... is liberally illustrated with archival photographs. It includes historical and scientific papers from symposia held in 1987 and 1995 to celebrate the birthdays of two of the radio telescopes at the Observatory. Book cover The National Radio Astronomy Observatory was formed in 1956 after the National Science Foundation decided to establish an observatory in the eastern United States for the study of faint radio signals from distant objects in the Universe. But it was Fun... reprints early memos from the group of scientists who searched the mountains for a suitable site -- an area free from radio transmitters and other sources of radio interference -- "in a valley surrounded by as many ranges of high mountains in as many directions as possible," which was "at least 50 miles distant from any city or other concentration of people." The committee settled on Green Bank, a small village in West Virginia, and the book documents the struggles that followed to create a world-class scientific facility in an isolated area more accustomed to cows than computers. Groundbreaking at the Observatory, then a patchwork of farms and fields, took place in October 1957, only a few days after the launch of Sputnik by the Soviet Union. A year later, Green Bank's first telescope was dedicated, and the book contains a transcription of speeches given at that ceremony, when the Cold War, the space race and America's scientific stature were issues of the hour. The centerpiece of the new Observatory was to be a highly-precise radio telescope 140 feet in diameter, but it was expected that it would soon be surpassed by dishes of much greater size. The book reprints internal memos, reports, and recollections of astronomers who were there, as the initial elation turned to frustration when the 140 Foot Telescope project became mired in technical difficulties, plans for larger dishes were put on hold, and the scientific staff of the fledgling Observatory struggled to create a National Observatory with inadequate equipment in a very remote location. Articles by David Heeschen and John Findlay tell the story of the creation of the 300 Foot Telescope, at that time the largest in the world, which went from initial concept to full operation in only 23 months, and began a rich life of research that put the NRAO on the world scientific map. The 300 Foot Telescope was originally intended to be an interim instrument, but as documented in the book, demand for its use was so high that it was kept in operation long after its initial planned retirement, with regular upgrades and new generations of electronics. The sudden collapse of the 300 Foot Telescope on a calm evening after 26 years of operation shocked the astronomical community. But it was Fun... features dramatic first-hand accounts by the people who were there that night: the telescope operator who found himself under a falling structure; the Observatory staff who at first could not believe what happened, and those who worked during the night and into the next day to secure the area, preserve information on what happened, and deal with the rush of publicity. The book includes extensive photographs and the Executive Summary Report of the panel which was commissioned to investigate the collapse and its implication for the design of other large radio telescopes. But it was Fun... will appeal to a variety of audiences. Historians of science will be interested in the articles by David Heeschen, Gerald Tape, and Hugh van Horn, on the evolution of the concept of a National Observatory, and the difficulties of putting the concepts into practice in Green Bank. Those interested in astronomical discovery will find fascinating and highly personal accounts by Peter Mezger on observations of radio recombination lines, by Lewis Snyder and Barry Turner on the early days of astrochemistry, by Don Backer and David Nice on observations of pulsars, and by David Shaffer, James Moran, Ken Kellermann and Barry Clark on aspects of the development of long baseline interferometric techniques. Today's generation of scientists will find interesting reminiscences by Patrick Palmer, Thomas Wilson, and Nobel Laureate Joseph Taylor on their experiences as graduate students doing thesis research at Green Bank, and from Sebastian von Hoerner and Jaap Baars on their work in telescope development. The volume also relates the entry of computers into radio astronomy, and reprints the one-page memo from 1960 which laid out the protocol for use of the new "single roll of magnetic tape" just acquired by the Observatory. A major portion of the book describes some singular events associated with this singular place: the first search for radio signals from extraterrestrial civilizations -- Project Ozma -- conducted by Dr. Frank Drake in 1960. But it was Fun... documents how this routine project thrust the NRAO into the national spotlight to the discomfort of its director, a distinguished astronomer of the old school. The book also recounts a few episodes in the amazing life of Grote Reber, the engineer who built the first-ever radio dish in his backyard and was a regular visitor to Green Bank. The NRAO Green Bank Observatory is an international center for research, and in two unique and frequently hilarious articles, Ken Kellermann and Barry Clark tell their stories of the first cooperative radio astronomical projects between the Soviet Union and the U.S., which involved transporting an atomic clock from Green Bank to a Soviet Observatory on the Black Sea at a time when international tensions were high, and it was impossible to make a phone call from the USSR to Green Bank. But it was Fun... includes a historical introduction which summarizes the early development of radio astronomy and events at the NRAO in Green Bank, a list of science highlights from the 300 Foot and 140 Foot Telescope research programs, chronologies of technical developments and lists of the early users. But it was Fun: the first 40 years of radio astronomy at Green Bank is a unique book which offers insight on the workings of a major scientific institution and the "overabundance of interesting people" who have populated it. The book is available from the NRAO. For information on ordering, see: http://www.gb.nrao.edu/epo/itwasfun.html The National Radio Astronomy Observatory is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc.
47 CFR 97.203 - Beacon station.
Code of Federal Regulations, 2010 CFR
2010-10-01
... Radio Astronomy Observatory, P.O. Box 2, Green Bank, WV 24944. (1) The notification must include the... Radio Astronomy Observatory at Green Bank, Pocahontas County, WV, for itself or on behalf of the Naval...
Code of Federal Regulations, 2010 CFR
2010-10-01
...) Radio Astronomy and Radio Research Installations. In order to minimize harmful interference at the National Radio Astronomy Observatory site located at Green Bank, Pocahontas County, W. Va., and at the... Astronomy Observatory, Post Office Box No. 2, Green Bank, WV 24944, in writing, of the technical particulars...
Code of Federal Regulations, 2011 CFR
2011-10-01
...) Radio Astronomy and Radio Research Installations. In order to minimize harmful interference at the National Radio Astronomy Observatory site located at Green Bank, Pocahontas County, W. Va., and at the... Astronomy Observatory, Post Office Box No. 2, Green Bank, WV 24944, in writing, of the technical particulars...
Code of Federal Regulations, 2013 CFR
2013-10-01
...) Radio Astronomy and Radio Research Installations. In order to minimize harmful interference at the National Radio Astronomy Observatory site located at Green Bank, Pocahontas County, W. Va., and at the... Astronomy Observatory, Post Office Box No. 2, Green Bank, WV 24944, in writing, of the technical particulars...
Code of Federal Regulations, 2014 CFR
2014-10-01
...) Radio Astronomy and Radio Research Installations. In order to minimize harmful interference at the National Radio Astronomy Observatory site located at Green Bank, Pocahontas County, W. Va., and at the... Astronomy Observatory, Post Office Box No. 2, Green Bank, WV 24944, in writing, of the technical particulars...
Code of Federal Regulations, 2012 CFR
2012-10-01
...) Radio Astronomy and Radio Research Installations. In order to minimize harmful interference at the National Radio Astronomy Observatory site located at Green Bank, Pocahontas County, W. Va., and at the... Astronomy Observatory, Post Office Box No. 2, Green Bank, WV 24944, in writing, of the technical particulars...
Federal Register 2010, 2011, 2012, 2013, 2014
2013-03-22
..., Notifications Concerning Interference to Radio Astronomy, Research and Receiving Installations. Form Number: N/A... Astronomy Observatory site located at Green, Pocahontas County, West Virginia, and at the Naval Radio... Interference Office, National Radio Astronomy Observatory, P.O. Box 2, Green Bank, West Virginia 24944...
A Green Robotic Observatory for Astronomy Education
NASA Astrophysics Data System (ADS)
Reddy, Vishnu; Archer, K.
2008-09-01
With the development of robotic telescopes and stable remote observing software, it is currently possible for a small institution to have an affordable astronomical facility for astronomy education. However, a faculty member has to deal with the light pollution (observatory location on campus), its nightly operations and regular maintenance apart from his day time teaching and research responsibilities. While building an observatory at a remote location is a solution, the cost of constructing and operating such a facility, not to mention the environmental impact, are beyond the reach of most institutions. In an effort to resolve these issues we have developed a robotic remote observatory that can be operated via the internet from anywhere in the world, has a zero operating carbon footprint and minimum impact on the local environment. The prototype observatory is a clam-shell design that houses an 8-inch telescope with a SBIG ST-10 CCD detector. The brain of the observatory is a low draw 12-volt harsh duty computer that runs the dome, telescope, CCD camera, focuser, and weather monitoring. All equipment runs of a 12-volt AGM-style battery that has low lead content and hence more environmental-friendly to dispose. The total power of 12-14 amp/hrs is generated from a set of solar panels that are large enough to maintain a full battery charge for several cloudy days. This completely eliminates the need for a local power grid for operations. Internet access is accomplished via a high-speed cell phone broadband connection or satellite link eliminating the need for a phone network. An independent observatory monitoring system interfaces with the observatory computer during operation. The observatory converts to a trailer for transportation to the site and is converted to a semi-permanent building without wheels and towing equipment. This ensures minimal disturbance to local environment.
47 CFR 5.91 - Notification of the National Radio Astronomy Observatory.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 47 Telecommunication 1 2012-10-01 2012-10-01 false Notification of the National Radio Astronomy... Astronomy Observatory. In order to minimize possible harmful interference at the National Radio Astronomy... Astronomy Observatory, P.O. Box NZ2, Green Bank, West Virginia, 24944, in writing, of the technical...
47 CFR 5.91 - Notification of the National Radio Astronomy Observatory.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 47 Telecommunication 1 2010-10-01 2010-10-01 false Notification of the National Radio Astronomy... Astronomy Observatory. In order to minimize possible harmful interference at the National Radio Astronomy... Astronomy Observatory, P.O. Box NZ2, Green Bank, West Virginia, 24944, in writing, of the technical...
47 CFR 5.91 - Notification of the National Radio Astronomy Observatory.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 47 Telecommunication 1 2011-10-01 2011-10-01 false Notification of the National Radio Astronomy... Astronomy Observatory. In order to minimize possible harmful interference at the National Radio Astronomy... Astronomy Observatory, P.O. Box NZ2, Green Bank, West Virginia, 24944, in writing, of the technical...
47 CFR 97.203 - Beacon station.
Code of Federal Regulations, 2013 CFR
2013-10-01
... written notification thereof to the Interference Office, National Radio Astronomy Observatory, P.O. Box 2... the proposed operation is received by the FCC from the National Radio Astronomy Observatory at Green...
47 CFR 97.203 - Beacon station.
Code of Federal Regulations, 2011 CFR
2011-10-01
... written notification thereof to the Interference Office, National Radio Astronomy Observatory, P.O. Box 2... the proposed operation is received by the FCC from the National Radio Astronomy Observatory at Green...
47 CFR 97.203 - Beacon station.
Code of Federal Regulations, 2014 CFR
2014-10-01
... written notification thereof to the Interference Office, National Radio Astronomy Observatory, P.O. Box 2... the proposed operation is received by the FCC from the National Radio Astronomy Observatory at Green...
47 CFR 97.203 - Beacon station.
Code of Federal Regulations, 2012 CFR
2012-10-01
... written notification thereof to the Interference Office, National Radio Astronomy Observatory, P.O. Box 2... the proposed operation is received by the FCC from the National Radio Astronomy Observatory at Green...
UniPOPS: Unified data reduction suite
NASA Astrophysics Data System (ADS)
Maddalena, Ronald J.; Garwood, Robert W.; Salter, Christopher J.; Stobie, Elizabeth B.; Cram, Thomas R.; Morgan, Lorrie; Vance, Bob; Hudson, Jerome
2015-03-01
UniPOPS, a suite of programs and utilities developed at the National Radio Astronomy Observatory (NRAO), reduced data from the observatory's single-dish telescopes: the Tucson 12-m, the Green Bank 140-ft, and archived data from the Green Bank 300-ft. The primary reduction programs, 'line' (for spectral-line reduction) and 'condar' (for continuum reduction), used the People-Oriented Parsing Service (POPS) as the command line interpreter. UniPOPS unified previous analysis packages and provided new capabilities; development of UniPOPS continued within the NRAO until 2004 when the 12-m was turned over to the Arizona Radio Observatory (ARO). The submitted code is version 3.5 from 2004, the last supported by the NRAO.
Code of Federal Regulations, 2014 CFR
2014-10-01
... stations in the 600 MHz downlink band in close proximity to Radio Astronomy Observatories. 27.19 Section 27... base and fixed stations in the 600 MHz downlink band in close proximity to Radio Astronomy Observatories. (a) Licensees must make reasonable efforts to protect the radio astronomy observatory at Green...
Push for Cheese: A Metaphor for Software Usability
NASA Astrophysics Data System (ADS)
Radziwill, Nicole; Shelton, Amy
2005-12-01
At the National Radio Astronomy Observatory's (NRAO) Science Center in Green Bank, W. Va., visitors curious about radio astronomy and the observatory's history and operations will discover an educational, entertaining experience. Employees also visit the science center, but their thoughts are more on afternoon snacks rather than distant galaxies. The employees of NRAO's Software Development Division in Green Bank have gained tremendous insight on the topic of software usability from many visits to the Science Center Café by pontificating upon the wisdom inherent in the design and use of the liquid cheese dispenser there.
47 CFR 25.203 - Choice of sites and frequencies.
Code of Federal Regulations, 2010 CFR
2010-10-01
... National Radio Astronomy Observatory: In order to minimize possible harmful interference at the National Radio Astronomy Observatory site located at Green Bank, Pocahontas County, W. Va., and at the Naval... such application with the Commission, simultaneously notify the Director, National Radio Astronomy...
47 CFR 25.203 - Choice of sites and frequencies.
Code of Federal Regulations, 2011 CFR
2011-10-01
... National Radio Astronomy Observatory: In order to minimize possible harmful interference at the National Radio Astronomy Observatory site located at Green Bank, Pocahontas County, W. Va., and at the Naval... such application with the Commission, simultaneously notify the Director, National Radio Astronomy...
47 CFR 25.203 - Choice of sites and frequencies.
Code of Federal Regulations, 2013 CFR
2013-10-01
... National Radio Astronomy Observatory: In order to minimize possible harmful interference at the National Radio Astronomy Observatory site located at Green Bank, Pocahontas County, W. Va., and at the Naval... such application with the Commission, simultaneously notify the Director, National Radio Astronomy...
47 CFR 25.203 - Choice of sites and frequencies.
Code of Federal Regulations, 2012 CFR
2012-10-01
... National Radio Astronomy Observatory: In order to minimize possible harmful interference at the National Radio Astronomy Observatory site located at Green Bank, Pocahontas County, W. Va., and at the Naval... such application with the Commission, simultaneously notify the Director, National Radio Astronomy...
Analysis of the red and green optical absorption spectrum of gas phase ammonia
NASA Astrophysics Data System (ADS)
Zobov, Nikolai F.; Coles, Phillip A.; Ovsyannikov, Roman I.; Kyuberis, Aleksandra A.; Hargreaves, Robert J.; Bernath, Peter F.; Tennyson, Jonathan; Yurchenko, Sergei N.; Polyansky, Oleg L.
2018-04-01
Room temperature NH3 absorption spectra recorded at the Kitt Peak National Solar Observatory in 1980 are analyzed. The spectra cover two regions in the visible: 15,200 - 15,700 cm-1 and 17,950 - 18,250 cm-1. These high overtone rotation-vibration spectra are analyzed using both combination differences and variational line lists. Two variational line lists were computed using the TROVE nuclear motion program: one is based on an ab initio potential energy surface (PES) while the other used a semi-empirical PES. Ab initio dipole moment surfaces are used in both cases. 95 energy levels with J = 1 - 7 are determined from analysis of the experimental spectrum in the 5νNH (red) region and 46 for 6νNH (green) region. These levels span four vibrational bands in each of the two regions, associated with stretching overtones.
Federal Register 2010, 2011, 2012, 2013, 2014
2010-06-14
..., Notifications Concerning Interference to Radio Astronomy, Research and Receiving Installations. Form Number: N/A... Astronomy Observatory site located at Green, Pocahontas County, West Virginia, and at the Naval Radio... the west, shall notify the Interference Office, National Radio Astronomy Observatory, P.O. Box 2...
NASA Astrophysics Data System (ADS)
Peterson, C. C.; D'Alto, N.; Frambach, A.; Gaskill, M.; Hostetler, A. J.; Johnson, R.; Novy, R.
2005-05-01
There are professional research observatories open to the public across the United States. Many of these offer public tours, star parties, classes, lectures, and educational movies about astronomy. Lick Observatory, the oldest continually operated professional observatory in the world, lies just east of San Jose, California. It is home to planet searches and offers special summer evening programs. McDonald Observatory, near Fort Davis, Texas, offers a wide variety of visitor programs year-round, including Star Parties three nights per week. Green Bank radio observatory in the mountains of West Virginia is home to the 360 foot Byrd Radio Telescope. Visitors are welcome year round and they can visit the new Science Center and exhibits. Other observatories noted are Sacramento Peak near Cloud Croft, New Mexico, the Very Large Array near Socorro, New Mexico, Palomar near San Diego, California, Cincinnati Observatory and Historic Landmark, and Arecibo Observatory in Puerto Rico.
Launching GUPPI: the Green Bank Ultimate Pulsar Processing Instrument
NASA Astrophysics Data System (ADS)
DuPlain, Ron; Ransom, Scott; Demorest, Paul; Brandt, Patrick; Ford, John; Shelton, Amy L.
2008-08-01
The National Radio Astronomy Observatory (NRAO) is launching the Green Bank Ultimate Pulsar Processing Instrument (GUPPI), a prototype flexible digital signal processor designed for pulsar observations with the Robert C. Byrd Green Bank Telescope (GBT). GUPPI uses field programmable gate array (FPGA) hardware and design tools developed by the Center for Astronomy Signal Processing and Electronics Research (CASPER) at the University of California, Berkeley. The NRAO has been concurrently developing GUPPI software and hardware using minimal software resources. The software handles instrument monitor and control, data acquisition, and hardware interfacing. GUPPI is currently an expert-only spectrometer, but supports future integration with the full GBT production system. The NRAO was able to take advantage of the unique flexibility of the CASPER FPGA hardware platform, develop hardware and software in parallel, and build a suite of software tools for monitoring, controlling, and acquiring data with a new instrument over a short timeline of just a few months. The NRAO interacts regularly with CASPER and its users, and GUPPI stands as an example of what reconfigurable computing and open-source development can do for radio astronomy. GUPPI is modular for portability, and the NRAO provides the results of development as an open-source resource.
Summary of interference measurements at selected radio observatories
NASA Technical Reports Server (NTRS)
Tarter, Jill C.
1990-01-01
Results are presented from a series of RF interference (RFI) observations conducted during 1989 and 1990 at selected radio astronomy observatories in order to choose a site for the SETI, where the local and orbital RFI would be as benign as possible for observations of weak electromagnetic signals. These observatories included the DSS13 at Goldstone (California), the Arecibo Observatory (Puerto Rico), the Algonquin Radio Observatory in Ottawa (Canada), the Ohio State University Radio Observatory in Columbus (Ohio), and the NRAO in Green Bank (West Virginia). The observations characterize the RFI environment at these sites from 1 to 10 GHz, using radio astronomy antennas, feeds, and receivers; SETI signal processors; and stand-alone equipment built specifically for this purpose. The results served as part of the basis for the selection (by the NASA SETI Microwave Observing Project) of NRAO as the site of choice for SETI observations.
Black Hole Jets Make Shock Waves
2014-07-02
A composite image of the spiral galaxy NGC 4258 showing X-ray emission observed with NASA Chandra X-ray Observatory blue and infrared emission observed with NASA Spitzer Space Telescope red and green.
NASA Astrophysics Data System (ADS)
Wilson, Robert C.
2018-01-01
This study aims to increase the sensitivity of pulsar timing arrays (PTAs) used by astronomers ofthe North American Nanohertz Observatory for Gravitational Waves (NANOGrav) to detectgravitational waves (GWs). Millisecond pulsars with many epochs of observations will be used todetermine if dispersive, frequency-dependent pulse time-of-arrival (TOA) delays caused by theinterstellar medium (ISM) can be more accurately predicted over numerous frequency channels.This project will contribute to the ongoing work to detect low-frequency GWs using PTAs. Dataused for this study will be from both the 110m telescope at the Green Bank Observatory in WestVirginia and the 305m telescope at the Arecibo Observatory in Puerto Rico.
NASA Astrophysics Data System (ADS)
Hynes, Shelly
2008-03-01
Research Experiences for Teachers (RET) is an NSF-funded program that provides high school teachers with the opportunity to do research at select institutions across the country in a wide variety of fields. I performed research at two institutions under this program; The National Radio Astronomy Observatory in Green Bank, WV in 2006 and Baylor University in Waco, TX in 2007. My work at NRAO utilized IDL programming to analyze the nonlinearities in the signal processing components of the GBT (Green Bank Telescope). My research at Baylor University required me to write a program in Mathematica to analyze the frequency of pulsation of variable white dwarfs, data that was taken at the Paul and Jane Meyer Observatory in Clifton, TX. I will explain how I have incorporated both research experiences into my courses and how each of these experiences has refocused my teaching.
NASA Astrophysics Data System (ADS)
Stevens, Jonathan
2017-07-01
Continuing advances in computational chemistry has permitted quantum mechanical calculation to assist in research in green chemistry and to contribute to the greening of chemical practice. Presented here are recent examples illustrating the contribution of computational quantum chemistry to green chemistry, including the possibility of using computation as a green alternative to experiments, but also illustrating contributions to greener catalysis and the search for greener solvents. Examples of applications of computation to ambitious projects for green synthetic chemistry using carbon dioxide are also presented.
NRAO Salutes Past, Looks to Future In 50th-Anniversary Science Meeting
NASA Astrophysics Data System (ADS)
2007-06-01
Radio telescopes now in operation or under construction will be indispensible to scientists wrestling with the big, unanswered questions of 21st-Century astrophysics. That was the conclusion of a wide-ranging scientific meeting held in Charlottesville, Virginia, June 18-21, to mark the 50th anniversary of the National Radio Astronomy Observatory (NRAO). 1957 Dedication Dedication of NRAO, 17 October 1957. Left to right: R.M. Emberson, L.V. Berkner, G.A. Nay, J.W. Findlay (seated in front of 140ft telescope model), N.L. Ashton, D.S. Heeschen, H. Hockenberry. CREDIT: NRAO/AUI/NSF Click on Image for Larger File ALMA Artist's conception of completed ALMA. CREDIT: NRAO/AUI/ESO Click on Image for Larger File (2.4 MB) Nearly 200 scientists from around the world heard presentations about the frontiers of astrophysics and how the challenges at those frontiers will be met. In specialties as disparate as seeking the nature of the mysterious Dark Energy that is speeding the Universe's expansion to unraveling the details of how stars and planets are formed, more than 70 presenters looked toward future research breakthroughs. "NRAO's telescopes have made landmark contributions to the vast explosion of astronomical knowledge of the past half- century, and we look eagerly to making even more important contributions in the coming decades," said Fred K.Y. Lo, NRAO's director. Over the four days of the meeting, discussions ranged from recollections of radio astronomy's pioneering days of vacuum-tube equipment and paper chart recorders to the design of telescopes that will produce amounts of data that will strain today's computers. Presenters pointed out that, in the coming decades, radio telescope observations will advance not only astronomy but also fields of basic physics such as gravitational radiation, particle physics, and the fundamental physical constants. "This meeting provided a great overview of where astrophysics stands today and where the challenges and opportunities of the future lie. We had a good mix of veterans from the early days of radio astronomy and the young researchers who will carry the science well into the observatory's next half-century," said NRAO astronomer Jim Condon, who organized the scientific program. In addition to the presentations, meeting participants got an in-depth tour of the NRAO Technology Center, where the observatory is developing and building state-of-the-art electronics for radio astronomy. A half-century ago, NRAO staffers were preparing to break ground for the observatory's first telescope at Green Bank, West Virginia. That telescope was dedicated the next year. It was followed by ever more capable telescopes, culminating in the Robert C. Byrd Green Bank Telescope, the largest fully-steerable dish antenna in the world. Work at Green Bank laid the technical foundation for the Very Large Array, near Socorro, New Mexico, which was dedicated in 1980. The continent-wide Very Long Baseline Array was dedicated in 1993. NRAO, along with partners in Europe and Japan, is constructing the Atacama Large Millimeter Array (ALMA) in northern Chile, a facility that will bring entirely new observing capabilities to the world's astronomers. ALMA is expected to provide the opportunity for major advances in the understanding of how stars and planets are formed, and to reveal some of the first stars and galaxies that formed in the early Universe, among other achievements. The National Radio Astronomy Observatory is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc.
Results of Spectral Corona Observations in Solar Activity Cycles 17-24
NASA Astrophysics Data System (ADS)
Aliev, A. Kh.; Guseva, S. A.; Tlatov, A. G.
2017-12-01
The results of the work of the global observation network are considered, and a comparative analysis of the data of various coronal observatories is performed. The coronal activity index has been reconstructed for the period 1939-2016 based on the data of various observatories in Kislovodsk system. For this purpose, the corona daily intensity maps from the Sacramento Peak and Lomnický Štít observatories according to the Solar-Geophysical Data journal have been digitized; they supplement the data of other observatories. The homogeneity and continuity of the corona observations at the Kislovodsk station, including activity cycle 24, is confirmed. Unfortunately, the only observatory at present that continues observation of the spectral corona in Fe XIV 5303 Å and Fe XIV 6374 Å lines is the Kislovodsk astronomical station Mountain Astronomical Station (MAS) of the Central Astronomical Observatory, Russian Academy of Sciences (Pulkovo). The data on the combined corona in 5303 Å line are analyzed. It is shown that there is a high correlation of the intensity index of green corona with solar radiation measurements in the vacuum UV region. Data on the beginning of the new 25th activity cycle in the corona at high latitudes are presented.
Code of Federal Regulations, 2012 CFR
2012-10-01
... to minimize possible impact on the operations of radio astronomy or other facilities that are highly..., radio astronomy, research, and receiving installation entity. The areas involved and procedures required... interference at the National Radio Astronomy Observatory site located at Green Bank, Pocahontas County, West...
Code of Federal Regulations, 2010 CFR
2010-10-01
... impact on the operations of radio astronomy or other facilities that are highly sensitive to interference. Consent throughout this paragraph means written consent from the quiet zone, radio astronomy, research... Radio Astronomy Observatory site located at Green Bank, Pocahontas County, West Virginia, and at the...
Code of Federal Regulations, 2011 CFR
2011-10-01
... impact on the operations of radio astronomy or other facilities that are highly sensitive to interference. Consent throughout this paragraph means written consent from the quiet zone, radio astronomy, research... Radio Astronomy Observatory site located at Green Bank, Pocahontas County, West Virginia, and at the...
Code of Federal Regulations, 2014 CFR
2014-10-01
... to minimize possible impact on the operations of radio astronomy or other facilities that are highly..., radio astronomy, research, and receiving installation entity. The areas involved and procedures required... interference at the National Radio Astronomy Observatory site located at Green Bank, Pocahontas County, West...
Code of Federal Regulations, 2013 CFR
2013-10-01
... to minimize possible impact on the operations of radio astronomy or other facilities that are highly..., radio astronomy, research, and receiving installation entity. The areas involved and procedures required... interference at the National Radio Astronomy Observatory site located at Green Bank, Pocahontas County, West...
East Peak Fire Burn Scar, Colorado [annotated
2017-12-08
On June 22, 2013, the Operational Land Imager (OLI) on Landsat 8 captured this false-color image of the East Peak fire burning in southern Colorado near Trinidad. Burned areas appear dark red, while actively burning areas look orange. Dark green areas are forests; light green areas are grasslands. Lightning ignited the blaze on June 19, 2013. By June 25, it had burned nearly 13,500 acres (5,500 hectares). NASA Earth Observatory image by Jesse Allen and Robert Simmon, using Landsat data from the U.S. Geological Survey. Caption by Adam Voiland. Instrument: Landsat 8 - OLI More images from this event: 1.usa.gov/14DesQC Credit: NASA Earth Observatory NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram
East Peak Fire Burn Scar, Colorado [high res
2017-12-08
On June 22, 2013, the Operational Land Imager (OLI) on Landsat 8 captured this false-color image of the East Peak fire burning in southern Colorado near Trinidad. Burned areas appear dark red, while actively burning areas look orange. Dark green areas are forests; light green areas are grasslands. Lightning ignited the blaze on June 19, 2013. By June 25, it had burned nearly 13,500 acres (5,500 hectares). NASA Earth Observatory image by Jesse Allen and Robert Simmon, using Landsat data from the U.S. Geological Survey. Caption by Adam Voiland. Instrument: Landsat 8 - OLI More images from this event: 1.usa.gov/14DesQC Credit: NASA Earth Observatory NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram
Kepler Supernova Remnant: A View from Chandra X-Ray Observatory
2004-10-06
The images indicate that the bubble of gas that makes up the supernova remnant appears different in various types of light. Chandra reveals the hottest gas [colored blue and colored green], which radiates in X-rays. http://photojournal.jpl.nasa.gov/catalog/PIA06908
The versatile GBT astronomical spectrometer (VEGAS): Current status and future plans
NASA Astrophysics Data System (ADS)
Prestage, Richard M.; Bloss, Marty; Brandt, Joe; Chen, Hong; Creager, Ray; Demorest, Paul; Ford, John; Jones, Glenn; Kepley, Amanda; Kobelski, Adam; Marganian, Paul; Mello, Melinda; McMahon, David; McCullough, Randy; Ray, Jason; Roshi, D. Anish; Werthimer, Dan; Whitehead, Mark
2015-07-01
The VEGAS multi-beam spectrometer (VEGAS) was built for the Green Bank Telescope (GBT) through a partnership between the National Radio Astronomy Observatory (NRAO) and the University of California at Berkeley. VEGAS is based on a Field Programmable Gate Array (FPGA) frontend and a heterogeneous computing backend comprised of Graphical Processing Units (GPUs) and CPUs. This system provides processing power to analyze up to 8 dual-polarization or 16 single-polarization inputs at bandwidths of up to 1.25 GHz per input. VEGAS was released for "shared-risk" observing in March 2014 and it became the default GBT spectral line backend in August 2014. Some of the early VEGAS observations include the Radio Ammonia Mid-Plane Survey, mapping of HCN/HCO+ in nearby galaxies, and a variety of radio-recombination line and pulsar projects. We will present some of the latest VEGAS science highlights.
Merging Galaxies Create a Binary Quasar
NASA Astrophysics Data System (ADS)
2010-02-01
Astronomers have found the first clear evidence of a binary quasar within a pair of actively merging galaxies. Quasars are the extremely bright centers of galaxies surrounding super-massive black holes, and binary quasars are pairs of quasars bound together by gravity. Binary quasars, like other quasars, are thought to be the product of galaxy mergers. Until now, however, binary quasars have not been seen in galaxies that are unambiguously in the act of merging. But images of a new binary quasar from the Carnegie Institution's Magellan telescope in Chile show two distinct galaxies with "tails" produced by tidal forces from their mutual gravitational attraction. "This is really the first case in which you see two separate galaxies, both with quasars, that are clearly interacting," says Carnegie astronomer John Mulchaey who made observations crucial to understanding the galaxy merger. Most, if not all, large galaxies, such as our galaxy the Milky Way, host super-massive black holes at their centers. Because galaxies regularly interact and merge, astronomers have assumed that binary super-massive black holes have been common in the Universe, especially during its early history. Black holes can only be detected as quasars when they are actively accreting matter, a process that releases vast amounts of energy. A leading theory is that galaxy mergers trigger accretion, creating quasars in both galaxies. Because most such mergers would have happened in the distant past, binary quasars and their associated galaxies are very far away and therefore difficult for most telescopes to resolve. The binary quasar, labeled SDSS J1254+0846, was initially detected by the Sloan Digital Sky Survey, a large scale astronomical survey of galaxies and over 120,000 quasars. Further observations by Paul Green of the Harvard-Smithsonian Center for Astrophysics and colleagues* using NASA's Chandra's X-ray Observatory and telescopes at Kitt Peak National Observatory in Arizona and Palomar Observatory in California indicated that the object was likely a binary quasar in the midst of a galaxy merger. Carnegie's Mulchaey then used the 6.5 meter Baade-Magellan telescope at the Las Campanas observatory in Chile to obtain deeper images and more detailed spectroscopy of the merging galaxies. "Just because you see two galaxies that are close to each other in the sky doesn't mean they are merging," says Mulchaey. "But from the Magellan images we can actually see tidal tails, one from each galaxy, which suggests that the galaxies are in fact interacting and are in the process of merging." Thomas Cox, now a fellow at the Carnegie Observatories, corroborated this conclusion using computer simulations of the merging galaxies. When Cox's model galaxies merged, they showed features remarkably similar to what Mulchaey observed in the Magellan images. "The model verifies the merger origin for this binary quasar system," he says. "It also hints that this kind of galaxy interaction is a key component of the growth of black holes and production of quasars throughout our universe." * The authors of the paper published in the Astrophysical Journal are Paul J. Green of the Harvard-Smithsonian Center for Astrophysics, Adam D. Myers of the University of Illinois at Urbana-Champaign, Wayne A. Barkhouse of the University of North Dakota, John S. Mulchaey of the Observatories of the Carnegie Institution for Science, Vardha N. Bennert of the Department of Physics, University of California, Santa Barbara, Thomas J. Cox of the Observatories of the Carnegie Institution for Science, Thomas L. Aldcroft of the Harvard-Smithsonian Center for Astrophysics, and Joan M. Wrobel of National Radio Astronomy Observatory, Socorro, NM. More information, including images and other multimedia, can be found at: http://chandra.harvard.edu and http://chandra.nasa.gov
The proposed NRAO millimeter array and its use for solar studies
NASA Technical Reports Server (NTRS)
Kundu, Mukul R.
1986-01-01
A brief summary is given of the proposed National Radio Astronomy Observatory (NRAO) Millimeter Array discussed at a workshop held in Green Bank, W. Va., September 30 to October 2, 1985. A brief description of the solar studies that can be made with such an array is provided.
Code of Federal Regulations, 2014 CFR
2014-01-01
..., Headquartered in Columbus, Ohio 7. Brookhaven National Laboratory, Upton, New York 8. Charles Stark Draper... 19. National Radiological Astronomy Observatory, Green Bank, West Virginia 20. National Renewable Energy Laboratory, Golden, Colorado 21. Oak Ridge Associated Universities, Oak Ridge, Tennessee 22. Rand...
Tectonic motion site survey of the National Radio Astronomy Observatory, Green Bank, West Virginia
NASA Technical Reports Server (NTRS)
Webster, W. J., Jr.; Allenby, R. J.; Hutton, L. K.; Lowman, P. D., Jr.; Tiedemann, H. A.
1979-01-01
A geological and geophysical site survey was made of the area around the National Radio Astronomy Observatory (NRAO) to determine whether there are at present local tectonic movements that could introduce significant errors to Very Long Baseline Interferometry (VLBI) geodetic measurements. The site survey consisted of a literature search, photogeologic mapping with Landsat and Skylab photographs, a field reconnaissance, and installation of a seismometer at the NRAO. It is concluded that local tectonic movement will not contribute significantly to VLBI errors. It is recommended that similar site surveys be made of all locations used for VLBI or laser ranging.
University Students' Subjective Knowledge of Green Computing and Pro-Environmental Behavior
ERIC Educational Resources Information Center
Ahmad, Tunku Badariah Tunku; Nordin, Mohamad Sahari
2014-01-01
This cross-sectional survey examined the structure of university students' subjective knowledge of green computing--hypothesized to be a multidimensional construct with three important dimensions--and its association with pro-environmental behavior (PEB). Using a previously validated green computing questionnaire, data were collected from 842…
NASA Astrophysics Data System (ADS)
Pogrebinsky, L.; Francile, C.
We report the development and the construction of an Interface to Control a robotized Astronomical Observatory (ICOA), which allows to control the operation of an observatory based on a Meade LX200 telescope. The interface operates together with a computer to control and supervise all the local variables of the observatory, and can take the control of it in risky situations. It serves as a link among the control computer and all the necessary devices for the astronomical observation such as the telescope, the dome, the weather station, the CCD camera, the calibration devices and the security devices. The computer receives orders from an operator who can be or not at the site of observation. The goal of this robotized observatory is the operation in a secure, autonomous and unattended way, with the purpose of to be used remotely by the students of the "Facultad de Ciencias Exactas, Físicas y Naturales" of the UNSJ. FULL TEXT IN SPANISH
Astronomical Research with the MicroObservatory Net
NASA Astrophysics Data System (ADS)
Brecher, K.; Sadler, P.; Gould, R.; Leiker, S.; Antonucci, P.; Deutsch, F.
1997-05-01
We have developed a fully integrated automated astronomical telescope system which combines the imaging power of a cooled CCD, with a self-contained and weatherized 15 cm reflecting optical telescope and mount. The MicroObservatory Net consists of five of these telescopes. They are currently being deployed around the world at widely distributed longitudes. Remote access to the MicroObservatories over the Internet has now been implemented. Software for computer control, pointing, focusing, filter selection as well as pattern recognition have all been developed as part of the project. The telescopes can be controlled in real time or in delay mode, from a Macintosh, PC or other computer using Web-based software. The Internet address of the telescopes is http://cfa- www.harvard.edu/cfa/sed/MicroObservatory/MicroObservatory.html. In the real-time mode, individuals have access to all of the telescope control functions without the need for an `on-site' operator. Users can sign up for a specific period of ti me. In the batch mode, users can submit requests for delayed telescope observations. After a MicroObservatory completes a job, the user is automatically notified by e-mail that the image is available for viewing and downloading from the Web site. The telescopes were designed for classroom instruction, as well as for use by students and amateur astronomers for original scientific research projects. We are currently examining a variety of technical and educational questions about the use of the telescopes including: (1) What are the best approaches to scheduling real-time versus batch mode observations? (2) What criteria should be used for allocating telescope time? (3) With deployment of more than one telescope, is it advantageous for each telescope to be used for just one type of observation, i.e., some for photometric use, others for imaging? And (4) What are the most valuable applications of the MicroObservatories in astronomical research? Support for the MicroObservatory Net has been provided by the NSF, Apple Computer, Inc. and Kodak, Inc.
Hubble Sees Stars and a Stripe in Celestial Fireworks
2017-12-08
Release date: July 1, 2008 This image is a composite of visible (or optical), radio, and X-ray data of the full shell of the supernova remnant from SN 1006. The radio data show much of the extent that the X-ray image shows. In contrast, only a small linear filament in the northwest corner of the shell is visible in the optical data. The object has an angular size of roughly 30 arcminutes (0.5 degree, or about the size of the full moon), and a physical size of 60 light-years (18 parsecs) based on its distance of nearly 7,000 light-years. The small green box along the bright filament at the top of the image corresponds to the dimensions of the Hubble release image. The optical data was obtained at the University of Michigan's 0.9-meter Curtis Schmidt telescope at the National Science Foundation's Cerro Tololo Inter-American Observatory (CTIO) near La Serena, Chile. H-alpha, continuum-subtracted data were provided by F. Winkler (Middlebury COllege) et al. The X-ray data were acquired from the Chandra X-ray Observatory's AXAF CCD Imaging Spectrometer (ACIS) at 0.5-3keV, and were provided by J. Hughes (Rutgers University) et al. The radio data, supplied by K. Dyer (NRAO, Socorro) et al., were a composite from the National Radio Astronomy Observatory's Very Large Array (NRAO/VLA) in Socorro, New Mexico, along with the Green Bank Telescope (GBT) in Green Bank, West Virginia. Data of the supernova remnant were blended on a visible-light stellar background created using the Digitized Sky Survey's Anglo-Australian Observatory (AAO2) blue and red plates. Photo Credit: NASA, ESA, and Z. Levay (STScI) Science Credit: Radio: NRAO/AUI/NSF GBT+VLA 1.4 GHz mosaic (Dyer, Maddalena and Cornwell, NRAO); X-ray: NASA/CXC/Rutgers/G. Cassam-Chenai and J. Hughes et al.; Optical: F.Winkler/Middlebury College and NOAO/AURA/NSF; and DSS To learn more about the Hubble Space Telescope go here: www.nasa.gov/mission_pages/hubble/main/index.html NASA Goddard Space Flight Center is home to the nation's largest organization of combined scientists, engineers and technologists that build spacecraft, instruments and new technology to study the Earth, the sun, our solar system, and the universe. Follow us on Twitter Join us on Facebook
AstroGrid: Taverna in the Virtual Observatory .
NASA Astrophysics Data System (ADS)
Benson, K. M.; Walton, N. A.
This paper reports on the implementation of the Taverna workbench by AstroGrid, a tool for designing and executing workflows of tasks in the Virtual Observatory. The workflow approach helps astronomers perform complex task sequences with little technical effort. Visual approach to workflow construction streamlines highly complex analysis over public and private data and uses computational resources as minimal as a desktop computer. Some integration issues and future work are discussed in this article.
2017-01-24
This image from NASA's Chandra X-ray Observatory shows spiral galaxy NGC 7331, center, in a three-color X-ray image. Red, green and blue colors are used for low, medium and high-energy X-rays, respectively. An unusual supernova called SN 2014C has been spotted in this galaxy. http://photojournal.jpl.nasa.gov/catalog/PIA21089
Division B Commission 6: Astronomical Telegrams
NASA Astrophysics Data System (ADS)
Yamaoka, H.; Green, D. W. E.; Samus, N. N.; Aksnes, K.; Gilmore, A. C.; Nakano, S.; Sphar, T.; Tichá, J.; Williams, G. V.
2016-04-01
IAU Commission 6 ``Astronomical Telegrams'' had a single business meeting during Honolulu General Assembly of the IAU. It took place on Tuesday, 11 August 2015. The meeting was attended by Hitoshi Yamaoka (President), Daniel Green (Director of the Central Bureau for Astronomical Telegrams, CBAT, via Skype), Steven Chesley (JPL), Paul Chodas (JPL), Alan Gilmore (Canterbury University), Shinjiro Kouzuma (Chukyo University), Paolo Mazzali (Co-Chair of the Supernova Working Group), Elena Pian (Scuola Normale Superiore di Pisa), Marion Schmitz (chair IAU Working Group Designations + NED), David Tholen (University of Hawaii), Jana Ticha (Klet Observatory), Milos Tichy (Klet Observatory), Giovanni Valsecchi (INAF\\slash Italy), Gareth Williams (Minor Planet Center). Apologies: Nikolai Samus (General Catalogue of Variable Stars, GCVS).
History of Chandra X-Ray Observatory
2000-12-04
Chandra X-Ray Observatory provided this composite X-ray (blue and green) and optical (red) image of the active galaxy NGC 1068 showing gas blowing away in a high-speed wind from the vicinity of a central supermassive black hole. Regions of intense star formation in the irner spiral arms of the galaxy are highlighted by both optical and x-ray emissions. A doughnut shaped cloud of cool gas and dust surrounding the black hole, known as the torus, appears as the elongated white spot . It has has a mass of about 5 million suns and is estimated to extend from within a few light years of the black hole out to about 300 light years.
Green's function methods in heavy ion shielding
NASA Technical Reports Server (NTRS)
Wilson, John W.; Costen, Robert C.; Shinn, Judy L.; Badavi, Francis F.
1993-01-01
An analytic solution to the heavy ion transport in terms of Green's function is used to generate a highly efficient computer code for space applications. The efficiency of the computer code is accomplished by a nonperturbative technique extending Green's function over the solution domain. The computer code can also be applied to accelerator boundary conditions to allow code validation in laboratory experiments.
Remote observing with the Nickel Telescope at Lick Observatory
NASA Astrophysics Data System (ADS)
Grigsby, Bryant; Chloros, Konstantinos; Gates, John; Deich, William T. S.; Gates, Elinor; Kibrick, Robert
2008-07-01
We describe a project to enable remote observing on the Nickel 1-meter Telescope at Lick Observatory. The purpose was to increase the subscription rate and create more economical means for graduate- and undergraduate students to observe with this telescope. The Nickel Telescope resides in a 125 year old dome on Mount Hamilton. Remote observers may work from any of the University of California (UC) remote observing facilities that have been created to support remote work at both Keck Observatory and Lick Observatory. The project included hardware and software upgrades to enable computer control of all equipment that must be operated by the astronomer; a remote observing architecture that is closely modeled on UCO/Lick's work to implement remote observing between UC campuses and Keck Observatory; new policies to ensure safety of Observatory staff and equipment, while ensuring that the telescope subsystems would be suitably configured for remote use; and new software to enforce the safety-related policies. The results increased the subscription rate from a few nights per month to nearly full subscription, and has spurred the installation of remote observing sites at more UC campuses. Thanks to the increased automation and computer control, local observing has also benefitted and is more efficient. Remote observing is now being implemented for the Shane 3- meter telescope.
History of Chandra X-Ray Observatory
2000-09-20
This Chandra image reveals, in detail, the turbulent debris created by a supernova explosion that was observed by the Danish Astronomer Tycho Brahe in the year 1572. The colors show different x-ray energies, with red, green, and blue representing low, medium, and high energies, respectively. Most likely caused by the destruction of a white dwarf star, a shock wave produced by the expanding debris is outlined by the sharp blue circular arcs of 20 million degree Celsius gas seen on the outer rim. The stellar debris, visible only by x-ray, has a temperature of about 10 million degrees, and shows up as mottled yellow, green, and red fingers of gas.
Deformation data modeling through numerical models: an efficient method for tracking magma transport
NASA Astrophysics Data System (ADS)
Charco, M.; Gonzalez, P. J.; Galán del Sastre, P.
2017-12-01
Nowadays, multivariate collected data and robust physical models at volcano observatories are becoming crucial for providing effective volcano monitoring. Nevertheless, the forecast of volcanic eruption is notoriously difficult. Wthin this frame one of the most promising methods to evaluate the volcano hazard is the use of surface ground deformation and in the last decades many developments in the field of deformation modeling has been achieved. In particular, numerical modeling allows realistic media features such as topography and crustal heterogeneities to be included, although it is still very time cosuming to solve the inverse problem for near-real time interpretations. Here, we present a method that can be efficiently used to estimate the location and evolution of magmatic sources base on real-time surface deformation data and Finite Element (FE) models. Generally, the search for the best-fitting magmatic (point) source(s) is conducted for an array of 3-D locations extending below a predefined volume region and the Green functions for all the array components have to be precomputed. We propose a FE model for the pre-computation of Green functions in a mechanically heterogeneous domain which eventually will lead to a better description of the status of the volcanic area. The number of Green functions is reduced here to the number of observational points by using their reciprocity relationship. We present and test this methodology with an optimization method base on a Genetic Algorithm. Following synthetic and sensitivity test to estimate the uncertainty of the model parameters, we apply the tool for magma tracking during 2007 Kilauea volcano intrusion and eruption. We show how data inversion with numerical models can speed up the source parameters estimations for a given volcano showing signs of unrest.
Code of Federal Regulations, 2012 CFR
2012-10-01
... radio astronomy service in the 1610.6-1613.8 MHz band against interference from 1.6/2.4 GHz Mobile... System. During periods of radio astronomy observations, land mobile earth stations shall not operate when... astronomy sites: Observatory Latitude (DMS) Longitude (DMS) Arecibo, PR 18 20 46 66 45 11 Green Bank...
Code of Federal Regulations, 2010 CFR
2010-10-01
... radio astronomy service in the 1610.6-1613.8 MHz band against interference from 1.6/2.4 GHz Mobile... System. During periods of radio astronomy observations, land mobile earth stations shall not operate when... astronomy sites: Observatory Latitude (DMS) Longitude (DMS) Arecibo, PR 18 20 46 66 45 11 Green Bank...
Code of Federal Regulations, 2011 CFR
2011-10-01
... radio astronomy service in the 1610.6-1613.8 MHz band against interference from 1.6/2.4 GHz Mobile... System. During periods of radio astronomy observations, land mobile earth stations shall not operate when... astronomy sites: Observatory Latitude (DMS) Longitude (DMS) Arecibo, PR 18 20 46 66 45 11 Green Bank...
Qualifying for the Green500: Experience with the newest generation of supercomputers at LANL
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yilk, Todd
The High Performance Computing Division of Los Alamos National Laboratory recently brought four new supercomputing platforms on line: Trinity with separate partitions built around the Haswell and Knights Landing CPU architectures for capability computing and Grizzly, Fire, and Ice for capacity computing applications. The power monitoring infrastructure of these machines is significantly enhanced over previous supercomputing generations at LANL and all were qualified at the highest level of the Green500 benchmark. Here, this paper discusses supercomputing at LANL, the Green500 benchmark, and notes on our experience meeting the Green500's reporting requirements.
Qualifying for the Green500: Experience with the newest generation of supercomputers at LANL
Yilk, Todd
2018-02-17
The High Performance Computing Division of Los Alamos National Laboratory recently brought four new supercomputing platforms on line: Trinity with separate partitions built around the Haswell and Knights Landing CPU architectures for capability computing and Grizzly, Fire, and Ice for capacity computing applications. The power monitoring infrastructure of these machines is significantly enhanced over previous supercomputing generations at LANL and all were qualified at the highest level of the Green500 benchmark. Here, this paper discusses supercomputing at LANL, the Green500 benchmark, and notes on our experience meeting the Green500's reporting requirements.
NASA Technical Reports Server (NTRS)
Tompkins, M. A.; Cheng, D. E. (Principal Investigator)
1981-01-01
The design and implementation of the PARPLT program are described. The program produces scatter plots of the greenness profile derived parameters alpha, beta, and t sub o computed by the CLASFYG program (alpha being the approximate greenness rise time; beta, the greenness decay time; and t sub o, the spectral crop emergence date). Statistical information concerning the parameters is also computed.
Sydney Observatory and astronomy teaching in the 90s
NASA Astrophysics Data System (ADS)
Lomb, N.
1996-05-01
Computers and the Internet have created a revolution in the way astronomy can be communicated to the public. At Sydney Observatory we make full use of these recent developments. In our lecture room a variety of sophisticated computer programs can show, with the help of a projection TV system, the appearance and motion of the sky at any place, date or time. The latest HST images obtained from the Internet can be shown, as can images taken through our own Meade 16 inch telescope. This recently installed computer-controlled telescope with its accurate pointing is an ideal instrument for a light-polluted site such as ours.
Finite-frequency structural sensitivities of short-period compressional body waves
NASA Astrophysics Data System (ADS)
Fuji, Nobuaki; Chevrot, Sébastien; Zhao, Li; Geller, Robert J.; Kawai, Kenji
2012-07-01
We present an extension of the method recently introduced by Zhao & Chevrot for calculating Fréchet kernels from a precomputed database of strain Green's tensors by normal mode summation. The extension involves two aspects: (1) we compute the strain Green's tensors using the Direct Solution Method, which allows us to go up to frequencies as high as 1 Hz; and (2) we develop a spatial interpolation scheme so that the Green's tensors can be computed with a relatively coarse grid, thus improving the efficiency in the computation of the sensitivity kernels. The only requirement is that the Green's tensors be computed with a fine enough spatial sampling rate to avoid spatial aliasing. The Green's tensors can then be interpolated to any location inside the Earth, avoiding the need to store and retrieve strain Green's tensors for a fine sampling grid. The interpolation scheme not only significantly reduces the CPU time required to calculate the Green's tensor database and the disk space to store it, but also enhances the efficiency in computing the kernels by reducing the number of I/O operations needed to retrieve the Green's tensors. Our new implementation allows us to calculate sensitivity kernels for high-frequency teleseismic body waves with very modest computational resources such as a laptop. We illustrate the potential of our approach for seismic tomography by computing traveltime and amplitude sensitivity kernels for high frequency P, PKP and Pdiff phases. A comparison of our PKP kernels with those computed by asymptotic ray theory clearly shows the limits of the latter. With ray theory, it is not possible to model waves diffracted by internal discontinuities such as the core-mantle boundary, and it is also difficult to compute amplitudes for paths close to the B-caustic of the PKP phase. We also compute waveform partial derivatives for different parts of the seismic wavefield, a key ingredient for high resolution imaging by waveform inversion. Our computations of partial derivatives in the time window where PcP precursors are commonly observed show that the distribution of sensitivity is complex and counter-intuitive, with a large contribution from the mid-mantle region. This clearly emphasizes the need to use accurate and complete partial derivatives in waveform inversion.
The great observatories for space astrophysics
NASA Technical Reports Server (NTRS)
Harwit, M.; Neal, V.
1986-01-01
Motivated by the ancient urge to observe, measure, compute, and understand the nature of the Universe, the available advanced technology is used to place entire observatories into space for investigations across the spectrum. Stellar evolution, development and nature of the Universe, planetary exploration, technology, NASA's role, and careers in asronomy are displayed.
Green Supercomputing at Argonne
Beckman, Pete
2018-02-07
Pete Beckman, head of Argonne's Leadership Computing Facility (ALCF) talks about Argonne National Laboratory's green supercomputingâeverything from designing algorithms to use fewer kilowatts per operation to using cold Chicago winter air to cool the machine more efficiently. Argonne was recognized for green computing in the 2009 HPCwire Readers Choice Awards. More at http://www.anl.gov/Media_Center/News/2009/news091117.html Read more about the Argonne Leadership Computing Facility at http://www.alcf.anl.gov/
NASA Astrophysics Data System (ADS)
Azzam, Y. A.; Ali, G. B.; Ismail, H. A.; Haroon, A.; Selim, I.
In this paper, we are going to introduce the Kottamia Astronomical Observatory, KAO, to the astronomical community. The current status of the telescope together with the available instrumentations is described. An upgrade stage including a new optical system and a computer controlling of both the telescope and dome are achieved. The specifications of a set of CCD cameras for direct imaging and spectroscopy are given. A grating spectrograph is recently gifted to KAO from Okayama Astrophysical Observatory, OAO, of the National Astronomical Observatories in Japan. This spectrograph is successfully tested and installed at the F/18 Cassegrain focus of the KAO 74" telescope.
47 CFR 15.712 - Interference protection requirements.
Code of Federal Regulations, 2014 CFR
2014-10-01
...-Less than 30 meters 11.1 1.2 30-Less than 50 meters 14.3 1.8 50-Less than 75 meters 18.0 2.0 75-Less... translator, Low Power TV (including Class A) and Multi-channel Video Programming Distributor (MVPD) receive... 04 N 121 28 24 W Arecibo Observatory 18 20 37 N 066 45 11 W Green Bank Telescope (GBT) 38 25 59 N 079...
47 CFR 15.712 - Interference protection requirements.
Code of Federal Regulations, 2012 CFR
2012-10-01
...-Less than 30 meters 11.1 1.2 30-Less than 50 meters 14.3 1.8 50-Less than 75 meters 18.0 2.0 75-Less... translator, Low Power TV (including Class A) and Multi-channel Video Programming Distributor (MVPD) receive... 04 N 121 28 24 W Arecibo Observatory 18 20 37 N 066 45 11 W Green Bank Telescope (GBT) 38 25 59 N 079...
47 CFR 15.712 - Interference protection requirements.
Code of Federal Regulations, 2013 CFR
2013-10-01
...-Less than 30 meters 11.1 1.2 30-Less than 50 meters 14.3 1.8 50-Less than 75 meters 18.0 2.0 75-Less... translator, Low Power TV (including Class A) and Multi-channel Video Programming Distributor (MVPD) receive... 04 N 121 28 24 W Arecibo Observatory 18 20 37 N 066 45 11 W Green Bank Telescope (GBT) 38 25 59 N 079...
Telescopes in Education: the Little Thompson Observatory
NASA Astrophysics Data System (ADS)
Schweitzer, A. E.; Melsheimer, T. T.
2003-12-01
The Little Thompson Observatory is the first community-built observatory that is part of a high school and accessible to other schools remotely, via the Internet. This observatory is the second member of the Telescopes in Education (TIE) project. Construction of the building was done completely by volunteer labor, and first light occurred in May 1999. The observatory is located on the grounds of Berthoud High School in northern Colorado. We are grateful to have received an IDEAS grant to provide teacher training workshops for K-12 schools to make use of the observatory, including remote observing from classrooms. Students connect to the observatory over the Internet, and then receive the images back on their local computers. A committee of teachers and administrators from the Thompson School District selected these workshops to count towards Incentive Credits (movement on the salary schedule) because the course meets the criteria: "Learning must be directly transferable to the classroom with students and relate to standards, assessment and/or technology." Our program is also accredited by Colorado State University.
A New Observatory for Eastern College: A Dream Realized
NASA Astrophysics Data System (ADS)
Bradstreet, D. H.
1996-12-01
The Eastern College Observatory began as a rooftop observing deck with one Celestron 8 telescope in 1976 as the workhorse instrument of the observational astronomy lab within the core curriculum. For 20 years the observing deck served as the crude observatory, being augmented through the years by other computerized Celestron 8's and a 17.5" diameter Dobsonian with computerized setting circles. The lab consisted primarily of visual observations and astrophotography. In 1987 plans were set into motion to raise money to build a permanent Observatory on the roof of the main classroom building. Fundraising efforts included three Jog-A-Thons (raising more than $40,000) and many donations from individuals and foundations. The fundraising was completed in 1996 and a two telescope observatory was constructed in the summer of 1996 complete with warm room, CCD cameras, computers, spectrograph, video network, and computerized single channel photometer. The telescopes are computerized 16" diameter Meade LX200 Schmidt-Cassegrains, each coupled to Gateway Pentium Pro 200 MHz computers. SBIG ST-8 CCD cameras were also secured for each telescope and an Optec SSP-7 photometer and Optomechanics Research 10C Spectrograph were also purchased. A Daystar H-alpha solar filter and Thousand Oaks visual light solar filter have expanded the Observatory's functionality to daytime observing as well. This is especially useful for the thousands of school children who frequent the Planetarium each year. The Observatory primarily serves the core astronomy lab where students must observe and photograph a prescribed number of celestial objects in a semester. Advanced students can take directed studies where they conduct photometry on eclipsing binaries or other variable stars or search for new asteroids. In addition, the Observatory and Planetarium are open to the public. Interested members of the community can reserve time on the telescopes and receive training and supervision from lab assistants. The lessons learned from building the Observatory as well as structural plans, equipment and curriculum development will be discussed in this poster.
NASA Astrophysics Data System (ADS)
Yurov, E. A.
1992-10-01
A method for the reduction of PZT plates which has been used at the Zvenigorod INASAN Observatory since 1986 is described. The formulas used for computing the coordinates of the stellar image in the focal plane at the midpoint of the exposure are correct to 0.0024 arcsec. Observations from February 1986 to October 1988 are compared with data of BIH and IERS, and the results of the comparison are used to compute the amplitudes of the annual terms of nonpolar variations in the observed latitudes and Delta(UTI).
The Little Thompson Observatory
NASA Astrophysics Data System (ADS)
Schweitzer, A.; Melsheimer, T.; Sackett, C.
1999-05-01
The Little Thompson Observatory is believed to be the first observatory built as part of a high school and accessible to other schools remotely, via the Internet. This observatory is the second member of the Telescopes in Education (TIE) project. Construction of the building and dome has been completed, and first light is planned for spring 1999. The observatory is located on the grounds of Berthoud High School in northern Colorado. Local schools and youth organizations will have prioritized access to the telescope, and there will also be opportunities for public viewing. After midnight, the telescope will be open to world-wide use by schools via the Internet following the model of the first TIE observatory, the 24" telescope on Mt. Wilson. Students remotely connect to the observatory over the Internet, and then receive the images on their local computers. The observatory grew out of grassroots support from the local community surrounding Berthoud, Colorado, a town of 3,500 residents. TIE has provided the observatory with a Tinsley 18" Cassegrain telescope on a 10-year loan. The facility has been built with tremendous support from volunteers and the local school district. We have received an IDEAS grant to provide teacher training workshops which will allow K-12 schools in northern Colorado to make use of the Little Thompson Observatory, including remote observing from classrooms.
VizieR Online Data Catalog: The MIT-Green Bank 5GHz Survey (Bennett+, 1986-91)
NASA Astrophysics Data System (ADS)
Bennett, C. L.; Lawrence, C. R.; Burke, B. F.; Hewitt, J. N.; Mahoney, J.
2003-08-01
The MIT-Green Bank 5GHz survey catalog was produced from four separate surveys with the National Radio Astronomy Observatory (NRAO) 91m transit telescope (Bennett et al., 1986ApJS...61....1B (MG1); Langston et al., 1990ApJS...72..621L (MG2); Griffith et al., 1990ApJS...74..129G (MG3); Griffith et al. 1991ApJS...75..801G (MG4)). The sky coverage of the various surveys is: 00h < RAB < 24h, -00d30'13" < DECB < +19d29'47" for MG1; 04h < RAJ < 21h, +17.0d < DECJ < +39d09' for MG2; 16h30m < RAB < 05h, +17d < DECB < +39d09' for MG3; and 15h30m < RAB < 02h30m, +37.00d < DECB < +50d58'48" for MG4; where RAB and DECB refer to B1950 coordinates, and RAJ and DECJ refer to J2000 coordinates. The catalog contains 20344 sources detected with a signal-to-noise ratio greater than 5 and 3836 possible detections (MG1) with a signal-to-noise ratio less than 5. Spectral indices are computed for MG1 sources also identified in the Texas 365MHz survey (Douglas et al. 1980), and for MG1-MG4 sources also identified in the NRAO 1400MHz Survey (Condon and Broderick 1985). (1 data file).
VizieR Online Data Catalog: The MIT-Green Bank 5GHz Survey (Bennett+, 1986-91)
NASA Astrophysics Data System (ADS)
Bennett, C. L.; Lawrence, C. R.; Burke, B. F.; Hewitt, J. N.; Mahoney, J.
1999-04-01
The MIT-Green Bank 5 GHz survey catalog was produced from four separate surveys with the National Radio Astronomy Observatory (NRAO) 91m transit telescope (Bennett et al., 1986ApJS...61....1B (MG1); Langston et al., 1990ApJS...72..621L (MG2); Griffith et al., 1990ApJS...74..129G (MG3); Griffith et al. 1991ApJS...75..801G (MG4)). The sky coverage of the various surveys is: 00h < RAB < 24h, -00d30'13" < DECB < +19d29'47" for MG1; 04h < RAJ < 21h, +17.0d < DECJ < +39d09' for MG2; 16h30m < RAB < 05h, +17d < DECB < +39d09' for MG3; and 15h30m < RAB < 02h30m, +37.00d < DECB < +50d58'48" for MG4; where RAB and DECB refer to B1950 coordinates, and RAJ and DECJ refer to J2000 coordinates. The catalog contains 20344 sources detected with a signal-to-noise ratio greater than 5 and 3836 possible detections (MG1) with a signal-to-noise ratio less than 5. Spectral indices are computed for MG1 sources also identified in the Texas 365 MHz survey (Douglas et al. 1980), and for MG1-MG4 sources also identified in the NRAO 1400 MHz Survey (Condon and Broderick 1985). (1 data file).
VizieR Online Data Catalog: MGIV (Fourth MIT-Green Bank) 5GHz Survey (Griffith+ 1991)
NASA Astrophysics Data System (ADS)
Griffith, M.; Langston, G.; Heflin, M.; Conner, S.; Burke, B.
1998-10-01
The MIT-Green Bank IV (MG IV) 5 GHz survey covers 0.504 sr of sky in the right ascension range 15.5 to 2.5 hours, between +37.00 and +50.98 degrees declination (B1950). The final MG IV catalog contains 3427 sources detected with a signal-to-noise ratio greater than 5. The catalog was produced from two separate north and south surveys with the National Radio Astronomy Observatory (NRAO) 91m transit telescope. The north survey was produced from data collected while scanning the telescope north from +39.0 to +50.98 degrees declination and the south survey from data collected from scans from +48.98 to +37.00 degrees declination. The completeness and reliability of the final source list is checked by examination of north and south source lists in a twice observed comparison region, lying between +39.15 and +48.83 degrees declination and excluding the area between +/-10 degrees Galactic latitude. The comparison region covers 0.270 sr of sky and contains 1094 sources. In this region, the MG IV catalog contains 423 sources brighter than 90 mJy and is shown to be 99.1 +/- 1.2% complete at this flux density level. Spectral indices are computed for sources identified in the NRAO 1400 MHz Survey (published by Condon and Broderick in 1985). A comparison of the spectral index distributions between +/- 10 and outside of +/- 10 degrees Galactic latitude is presented. (1 data file).
History of Chandra X-Ray Observatory
2000-11-01
This image is a color composite of the supernova remnant E0102-72: x-ray (blue), optical (green), and radio (red). E0102-72 is the remnant of a star that exploded in a nearby galaxy known as the Small Magellanic Cloud. The star exploded outward at speeds in excess of 20 million kilometers per hour (12 million mph) and collided with surrounding gas. This collision produced two shock waves, or cosmic sonic booms, one traveling outward, and the other rebounding back into the material ejected by the explosion. The radio image, shown in red, was made using the Australia Telescope Compact Array. The radio waves are due to extremely high-energy electrons spiraling around magnetic field lines in the gas and trace the outward moving shock wave. The Chandra X-ray Observatory image, shown in blue, shows gas that has been heated to millions of degrees by the rebounding, or reverse shock wave. The x-ray data show that this gas is rich in oxygen and neon. These elements were created by nuclear reactions inside the star and hurled into space by the supernova. The Hubble Space Telescope optical image, shown in green, shows dense clumps of oxygen gas that have "cooled" to about 30,000 degrees. Photo Credit: X-ray (NASA/CXC/SAO); optical (NASA/HST): radio: (ACTA)
GreenView and GreenLand Applications Development on SEE-GRID Infrastructure
NASA Astrophysics Data System (ADS)
Mihon, Danut; Bacu, Victor; Gorgan, Dorian; Mészáros, Róbert; Gelybó, Györgyi; Stefanut, Teodor
2010-05-01
The GreenView and GreenLand applications [1] have been developed through the SEE-GRID-SCI (SEE-GRID eInfrastructure for regional eScience) FP7 project co-funded by the European Commission [2]. The development of environment applications is a challenge for Grid technologies and software development methodologies. This presentation exemplifies the development of the GreenView and GreenLand applications over the SEE-GRID infrastructure by the Grid Application Development Methodology [3]. Today's environmental applications are used in vary domains of Earth Science such as meteorology, ground and atmospheric pollution, ground metal detection or weather prediction. These applications run on satellite images (e.g. Landsat, MERIS, MODIS, etc.) and the accuracy of output results depends mostly of the quality of these images. The main drawback of such environmental applications regards the need of computation power and storage power (some images are almost 1GB in size), in order to process such a large data volume. Actually, almost applications requiring high computation resources have approached the migration onto the Grid infrastructure. This infrastructure offers the computing power by running the atomic application components on different Grid nodes in sequential or parallel mode. The middleware used between the Grid infrastructure and client applications is ESIP (Environment Oriented Satellite Image Processing Platform), which is based on gProcess platform [4]. In its current format, gProcess is used for launching new processes on the Grid nodes, but also for monitoring the execution status of these processes. This presentation highlights two case studies of Grid based environmental applications, GreenView and GreenLand [5]. GreenView is used in correlation with MODIS (Moderate Resolution Imaging Spectroradiometer) satellite images and meteorological datasets, in order to produce pseudo colored temperature and vegetation maps for different geographical CEE (Central Eastern Europe) regions. On the other hand, GreenLand is used for generating maps for different vegetation indexes (e.g. NDVI, EVI, SAVI, GEMI) based on Landsat satellite images. Both applications are using interpolation and random value generation algorithms, but also specific formulas for computing vegetation index values. The GreenView and GreenLand applications have been experimented over the SEE-GRID infrastructure and the performance evaluation is reported in [6]. The improvement of the execution time (obtained through a better parallelization of jobs), the extension of geographical areas to other parts of the Earth, and new user interaction techniques on spatial data and large set of satellite images are the goals of the future work. References [1] GreenView application on Wiki, http://wiki.egee-see.org/index.php/GreenView [2] SEE-GRID-SCI Project, http://www.see-grid-sci.eu/ [3] Gorgan D., Stefanut T., Bâcu V., Mihon D., Grid based Environment Application Development Methodology, SCICOM, 7th International Conference on "Large-Scale Scientific Computations", 4-8 June, 2009, Sozopol, Bulgaria, (To be published by Springer), (2009). [4] Gorgan D., Bacu V., Stefanut T., Rodila D., Mihon D., Grid based Satellite Image Processing Platform for Earth Observation Applications Development. IDAACS'2009 - IEEE Fifth International Workshop on "Intelligent Data Acquisition and Advanced Computing Systems: Technology and Applications", 21-23 September, Cosenza, Italy, IEEE Published in Computer Press, 247-252 (2009). [5] Mihon D., Bacu V., Stefanut T., Gorgan D., "Grid Based Environment Application Development - GreenView Application". ICCP2009 - IEEE 5th International Conference on Intelligent Computer Communication and Processing, 27 Aug, 2009 Cluj-Napoca. Published by IEEE Computer Press, pp. 275-282 (2009). [6] Danut Mihon, Victor Bacu, Dorian Gorgan, Róbert Mészáros, Györgyi Gelybó, Teodor Stefanut, Practical Considerations on the GreenView Application Development and Execution over SEE-GRID. SEE-GRID-SCI User Forum, 9-10 Dec 2009, Bogazici University, Istanbul, Turkey, ISBN: 978-975-403-510-0, pp. 167-175 (2009).
Early laser operations at the Large Binocular Telescope Observatory
NASA Astrophysics Data System (ADS)
Rahmer, Gustavo; Lefebvre, Michael; Christou, Julian; Raab, Walfried; Rabien, Sebastian; Ziegleder, Julian; Borelli, José L.; Gässler, Wolfgang
2014-08-01
ARGOS is the GLAO (Ground-Layer Adaptive Optics) Rayleigh-based LGS (Laser Guide Star) facility for the Large Binocular Telescope Observatory (LBTO). It is dedicated for observations with LUCI1 and LUCI2, LBTO's pair of NIR imagers and multi-object spectrographs. The system projects three laser beams from the back of each of the two secondary mirror units, which create two constellations circumscribed on circles of 2 arcmin radius with 120 degree spacing. Each of the six Nd:YAG lasers provides a beam of green (532nm) pulses at a rate of 10kHz with a power of 14W to 18W. We achieved first on-sky propagation on the night of November 5, 2013, and commissioning of the full system will take place during 2014. We present the initial results of laser operations at the observatory, including safety procedures and the required coordination with external agencies (FAA, Space Command, and Military Airspace Manager). We also describe our operational procedures and report on our experiences with aircraft spotters. Future plans for safer and more efficient aircraft monitoring and detection are discussed.
Hurricane Isaac by Night [annotated
2017-12-08
NASA image acquired August 29, 2012 1:57 a.m EDT Hurricane Isaac lit up by moonlight as it spins over the city of New Orleans, La. at 1:57 am central daylight savings time the morning of August 29, 2012. The Suomi National Polar-orbiting Partnership (NPP) satellite captured these images with its Visible Infrared Imaging Radiometer Suite (VIIRS). The "day-night band" of VIIRS detects light in a range of wavelengths from green to near-infrared and uses light intensification to enable the detection of dim signals. Suomi NPP is the result of a partnership between NASA, the National Oceanic and Atmospheric Administration and the Department of Defense. Image Credit: NASA/NOAA, Earth Observatory NASA Earth Observatory image by Jesse Allen and Robert Simmon, using VIIRS Day Night Band data. Credit: NASA Earth Observatory NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram
2010-06-01
Woods Hole, MA 02543, USA 3 Raytheon Intelligence and Information Systems, Aurora , CO 80011, USA 4 Scripps Institution of Oceanography, La Jolla...Amazon.com, Amazon Web Services for the Amazon Elastic Compute Cloud ( Amazon EC2). http://aws.amazon.com/ec2/. [4] M. Arrott, B. Demchak, V. Ermagan, C
Computers at the Albuquerque Seismological Laboratory
Hoffman, J.
1979-01-01
The Worldwide Standardized Seismograph Network (WWSSN) is managed by the U.S Geological Survey in Albuquerque, N. Mex. It consists of a global network of seismographs housed in seismic observatories throughout the world. An important recent addition to this network are the Seismic Research Observatories (SRO) which combine a borehole seismometer with a modern digital data recording system.
The Little Thompson Observatory
NASA Astrophysics Data System (ADS)
Schweitzer, A. E.; VanLew, K.; Melsheimer, T.; Sackett, C.
1999-12-01
The Little Thompson Observatory is the second member of the Telescopes in Education (TIE) project. Construction of the dome and the remote control system has been completed, and the telescope is now on-line and operational over the Internet. The observatory is located on the grounds of Berthoud High School in northern Colorado. Local schools and youth organizations have prioritized access to the telescope, and there are monthly opportunities for public viewing. In the future, the telescope will be open after midnight to world-wide use by schools following the model of the first TIE observatory, the 24" telescope on Mt. Wilson. Students remotely connect to the observatory over the Internet, and then receive the images on their local computers. The observatory grew out of grassroots support from the local community surrounding Berthoud, Colorado, a town of 3,500 residents. TIE has provided the observatory with a Tinsley 18" Cassegrain telescope on a 10-year loan. The facility has been built with tremendous support from volunteers and the local school district. With funding from an IDEAS grant, we have begun teacher training workshops which will allow K-12 schools in northern Colorado to make use of the Little Thompson Observatory, including remote observing from classrooms.
21st Century Lightning Protection for High Altitude Observatories
NASA Astrophysics Data System (ADS)
Kithil, Richard
2013-05-01
One of the first recorded lightning insults to an observatory was in January 1890 at the Ben Nevis Observatory in Scotland. In more recent times lightning has caused equipment losses and data destruction at the US Air Force Maui Space Surveillance Complex, the Cerro Tololo observatory and the nearby La Serena scientific and technical office, the VLLA, and the Apache Point Observatory. In August 1997 NOAA's Climate Monitoring and Diagnostic Laboratory at Mauna Loa Observatory was out of commission for a month due to lightning outages to data acquisition computers and connected cabling. The University of Arizona has reported "lightning strikes have taken a heavy toll at all Steward Observatory sites." At Kitt Peak, extensive power down protocols are in place where lightning protection for personnel, electrical systems, associated electronics and data are critical. Designstage lightning protection defenses are to be incorporated at NSO's ATST Hawaii facility. For high altitude observatories lightning protection no longer is as simple as Franklin's 1752 invention of a rod in the air, one in the ground and a connecting conductor. This paper discusses selection of engineered lightning protection subsystems in a carefully planned methodology which is specific to each site.
Real-time control of the robotic lunar observatory telescope
Anderson, J.M.; Becker, K.J.; Kieffer, H.H.; Dodd, D.N.
1999-01-01
The US Geological Survey operates an automated observatory dedicated to the radiometry of the Moon with the objective of developing a multispectral, spatially resolved photometric model of the Moon to be used in the calibration of Earth-orbiting spacecraft. Interference filters are used with two imaging instruments to observe the Moon in 32 passbands from 350-2500 nm. Three computers control the telescope mount and instruments with a fourth computer acting as a master system to control all observation activities. Real-time control software has been written to operate the instrumentation and to automate the observing process. The observing software algorithms use information including the positions of objects in the sky, the phase of the Moon, and the times of evening and morning twilight to decide how to observe program objects. The observatory has been operating in a routine mode since late 1995 and is expected to continue through at least 2002 without significant modifications.
NASA Technical Reports Server (NTRS)
Atwood, Christopher A.
1993-01-01
The June 1992 to May 1993 grant NCC-2-677 provided for the continued demonstration of Computational Fluid Dynamics (CFD) as applied to the Stratospheric Observatory for Infrared Astronomy (SOFIA). While earlier grant years allowed validation of CFD through comparison against experiments, this year a new design proposal was evaluated. The new configuration would place the cavity aft of the wing, as opposed to the earlier baseline which was located immediately aft of the cockpit. This aft cavity placement allows for simplified structural and aircraft modification requirements, thus lowering the program cost of this national astronomy resource. Three appendices concerning this subject are presented.
NASA Technical Reports Server (NTRS)
1998-01-01
Why are space observatories important? The answer concerns twinkling stars in the night sky. To reach telescopes on Earth, light from distant objects has to penetrate Earth's atmosphere. Although the sky may look clear, the gases that make up our atmosphere cause problems for astronomers. These gases absorb the majority of radiation emanating from celestial bodies so that it never reaches the astronomer's telescope. Radiation that does make it to the surface is distorted by pockets of warm and cool air, causing the twinkling effect. In spite of advanced computer enhancement, the images finally seen by astronomers are incomplete. NASA, in conjunction with other countries' space agencies, commercial companies, and the international community, has built observatories such as the Hubble Space Telescope, the Compton Gamma Ray Observatory, and the Chandra X-ray Observatory to find the answers to numerous questions about the universe. With the capabilities the Space Shuttle provides, scientist now have the means for deploying these observatories from the Shuttle's cargo bay directly into orbit.
The Little Thompson Observatory
NASA Astrophysics Data System (ADS)
Schweitzer, A.; Melsheimer, T.; Rideout, C.; Vanlew, K.
1998-12-01
The Little Thompson Observatory is believed to be the first observatory built as part of a high school and accessible to other schools remotely, via the Internet. This observatory is the second member of the Telescopes in Education (TIE) project. Construction is nearly completed and first light is planned for fall 1998. The observatory is located on the grounds of Berthoud High School in northern Colorado. Local schools and youth organizations will have prioritized access to the telescope, and there will also be opportunities for public viewing. After midnight, the telescope will be open to world-wide use by schools via the Internet following the model of the first TIE observatory, the 24" telescope on Mt. Wilson. That telescope has been in use for the past four years by up to 50 schools per month. Students remotely connect to the observatory over the Internet, and then receive the images on their local computers. The observatory grew out of grassroots support from the local community surrounding Berthoud, Colorado, a town of 3,500 residents. TIE has provided the observatory with a Tinsley 18" Cassegrain telescope on a 10-year loan. The facility has been built with tremendous support from volunteers and the local school district. We have applied for an IDEAS grant to provide teacher training workshops which will allow K-12 schools in northern Colorado to make use of the Little Thompson Observatory, including remote observing from classrooms.
A real-time moment-tensor inversion system (GRiD-MT-3D) using 3-D Green's functions
NASA Astrophysics Data System (ADS)
Nagao, A.; Furumura, T.; Tsuruoka, H.
2016-12-01
We developed a real-time moment-tensor inversion system using 3-D Green's functions (GRiD-MT-3D) by improving the current system (GRiD-MT; Tsuruoka et al., 2009), which uses 1-D Green's functions for longer periods than 20 s. Our moment-tensor inversion is applied to the real-time monitoring of earthquakes occurring beneath Kanto basin area. The basin, which is constituted of thick sediment layers, lies on the complex subduction of the Philippine-Sea Plate and the Pacific Plate that can significantly affect the seismic wave propagation. We compute 3-D Green's functions using finite-difference-method (FDM) simulations considering a 3-D velocity model, which is based on the Japan Integrated Velocity Structure Model (Koketsu et al., 2012), that includes crust, mantle, and subducting plates. The 3-D FDM simulations are computed over a volume of 468 km by 432 km by 120 km in the EW, NS, and depth directions, respectively, that is discretized into 0.25 km grids. Considering that the minimum S wave velocity of the sedimentary layer is 0.5 km/s, simulations can compute seismograms up to 0.5 Hz. We calculate Green's functions between 24,700 sources, which are distributed every 0.1° in the horizontal direction and every 9 km in depth direction, and 13 F-net stations. To compute this large number of Green's functions, we used the EIC parallel computer of ERI. The reciprocity theory, which switches the source and station positions, is used to reduce total computation costs. It took 156 hours to compute all the Green's functions. Results show that at long-periods (T>15 s), only small differences are observed between the 3-D and 1-D Green's functions as indicated by high correlation coefficients of 0.9 between the waveforms. However, at shorter periods (T<10 s), the differences become larger and the correlation coefficients drop to 0.5. The effect of the 3-D heterogeneous structure especially affects the Green's functions for the ray paths that across complex geological structures, such as the sedimentary basin or the subducting plates. After incorporation of the 3-D Green's functions in the GRiD-MT-3D system, we compare the results to the former GRiD-MT system to demonstrate the effectiveness of the new system in terms of variance reduction and accuracy of the moment-tensor estimation for much smaller events than the current one.
The Virtual Watershed Observatory: Cyberinfrastructure for Model-Data Integration and Access
NASA Astrophysics Data System (ADS)
Duffy, C.; Leonard, L. N.; Giles, L.; Bhatt, G.; Yu, X.
2011-12-01
The Virtual Watershed Observatory (VWO) is a concept where scientists, water managers, educators and the general public can create a virtual observatory from integrated hydrologic model results, national databases and historical or real-time observations via web services. In this paper, we propose a prototype for automated and virtualized web services software using national data products for climate reanalysis, soils, geology, terrain and land cover. The VWO has the broad purpose of making accessible water resource simulations, real-time data assimilation, calibration and archival at the scale of HUC 12 watersheds (Hydrologic Unit Code) anywhere in the continental US. Our prototype for model-data integration focuses on creating tools for fast data storage from selected national databases, as well as the computational resources necessary for a dynamic, distributed watershed simulation. The paper will describe cyberinfrastructure tools and workflow that attempts to resolve the problem of model-data accessibility and scalability such that individuals, research teams, managers and educators can create a WVO in a desired context. Examples are given for the NSF-funded Shale Hills Critical Zone Observatory and the European Critical Zone Observatories within the SoilTrEC project. In the future implementation of WVO services will benefit from the development of a cloud cyber infrastructure as the prototype evolves to data and model intensive computation for continental scale water resource predictions.
Lessons from the MicroObservatory Net
NASA Astrophysics Data System (ADS)
Brecher, K.; Sadler, P.; Gould, R.; Leiker, S.; Antonucci, P.; Deutsch, F.
1998-12-01
Over the past several years, we have developed a fully integrated automated astronomical telescope system which combines the imaging power of a cooled CCD, with a self-contained and weatherized 15 cm reflecting optical telescope and mount. Each telescope can be pointed and focused remotely, and filters, field of view and exposure times can be changed easily. The MicroObservatory Net consists of five of these telescopes. They are being deployed around the world at widely distributed longitudes for access to distant night skies during local daytime. Remote access to the MicroObservatories over the Internet has been available to select schools since 1995. The telescopes can be controlled in real time or in delay mode, from any computer using Web-based software. Individuals have access to all of the telescope control functions without the need for an `on-site' operator. After a MicroObservatory completes a job, the user is automatically notified by e-mail that the image is available for viewing and downloading from the Web site. Images are archived at the Web site, along with sample challenges and a user bulletin board, all of which encourage collaboration between schools. The Internet address of the telescopes is http://mo-www.harvard.edu/MicroObservatory/. The telescopes were designed for classroom instruction by teachers, as well as for use by students and amateur astronomers for original scientific research projects. In this talk, we will review some of the experiences we, students and teachers have had in using the telescopes. Support for the MicroObservatory Net has been provided by the NSF, Apple Computer, Inc. and Kodak, Inc.
47 CFR 15.712 - Interference protection requirements.
Code of Federal Regulations, 2011 CFR
2011-10-01
....1 10-30 meters 14.4 0.74 (b) TV translator, Low Power TV (including Class A) and Multi-channel Video... Telescope Array 121 28 24 W 40 49 04 N Arecibo Observatory 066 45 11 W 18 20 46 N Green Bank Telescope (GBT... 07 07 W 34 18 04 N Kitt Peak, AZ 111 36 42 W 31 57 22 N Los Alamos, NM 106 14 42 W 35 46 30 N Ft...
Supernova SN 2014C Optical and X-Ray
2017-01-24
This visible-light image from the Sloan Digital Sky Survey shows spiral galaxy NGC 7331, center, where astronomers observed the unusual supernova SN 2014C . The inset images are from NASA's Chandra X-ray Observatory, showing a small region of the galaxy before the supernova explosion (left) and after it (right). Red, green and blue colors are used for low, medium and high-energy X-rays, respectively. http://photojournal.jpl.nasa.gov/catalog/PIA21088
Back to the future: virtualization of the computing environment at the W. M. Keck Observatory
NASA Astrophysics Data System (ADS)
McCann, Kevin L.; Birch, Denny A.; Holt, Jennifer M.; Randolph, William B.; Ward, Josephine A.
2014-07-01
Over its two decades of science operations, the W.M. Keck Observatory computing environment has evolved to contain a distributed hybrid mix of hundreds of servers, desktops and laptops of multiple different hardware platforms, O/S versions and vintages. Supporting the growing computing capabilities to meet the observatory's diverse, evolving computing demands within fixed budget constraints, presents many challenges. This paper describes the significant role that virtualization is playing in addressing these challenges while improving the level and quality of service as well as realizing significant savings across many cost areas. Starting in December 2012, the observatory embarked on an ambitious plan to incrementally test and deploy a migration to virtualized platforms to address a broad range of specific opportunities. Implementation to date has been surprisingly glitch free, progressing well and yielding tangible benefits much faster than many expected. We describe here the general approach, starting with the initial identification of some low hanging fruit which also provided opportunity to gain experience and build confidence among both the implementation team and the user community. We describe the range of challenges, opportunities and cost savings potential. Very significant among these was the substantial power savings which resulted in strong broad support for moving forward. We go on to describe the phasing plan, the evolving scalable architecture, some of the specific technical choices, as well as some of the individual technical issues encountered along the way. The phased implementation spans Windows and Unix servers for scientific, engineering and business operations, virtualized desktops for typical office users as well as more the more demanding graphics intensive CAD users. Other areas discussed in this paper include staff training, load balancing, redundancy, scalability, remote access, disaster readiness and recovery.
Detecting stochastic backgrounds of gravitational waves with pulsar timing arrays
NASA Astrophysics Data System (ADS)
Siemens, Xavier
2016-03-01
For the past decade the North American Nanohertz Observatory for Gravitational Waves (NANOGrav) has been using the Green Bank Telescope and the Arecibo Observatory to monitor millisecond pulsars. NANOGrav, along with two other international collaborations, the European Pulsar Timing Array and the Parkes Pulsar Timing Array in Australia, form a consortium of consortia: the International Pulsar Timing Array (IPTA). The goal of the IPTA is to directly detect low-frequency gravitational waves which cause small changes to the times of arrival of radio pulses from millisecond pulsars. In this talk I will discuss the work of NANOGrav and the IPTA, as well as our sensitivity to stochastic backgrounds of gravitational waves. I will show that a detection of the background produced by supermassive black hole binaries is possible by the end of the decade. Supported by the NANOGrav Physics Frontiers Center.
History of Chandra X-Ray Observatory
2004-08-12
NASA’s Chandra X-Ray Observatory (CXO) was launched July 22, 1999 aboard the Space Shuttle Columbia, STS-93 mission. This image was produced by combining a dozen CXO observations made of a 130 light-year region in the center of the Milky Way over the last 5 years. The colors represent low (red), medium (green) and high (blue) energy x-rays. Thanks to Chandra's unique resolving power, astronomers have now been able to identify thousands of point-like x-ray sources due to neutron stars, black holes, white dwarfs, foreground stars, and background galaxies. What remains is a diffuse x-ray glow extending from the upper left to the lower right, along the direction of the disk of the galaxy. NASA’s Marshall Space Flight Center in Huntsville, Alabama manages the Chandra program. (NASA/CXC/UCLA/M. Muno et al.)
The Pulsar Search Collaboratory: A Comprehensive Project for Students and Teachers
NASA Astrophysics Data System (ADS)
Rosen, Rachel; Heatherly, S.; McLauglin, M.; Lorimer, D.
2009-01-01
The National Radio Astronomy Observatory (NRAO) and West Virginia University (WVU) have partnered to improve the quality of science education in West Virginia high schools through the Pulsar Search Collaboratory (PSC). One of the primary goals of the PSC is to engage students in STEM (science, technology, engineering, and mathematics) and related fields by using information technology to conduct current scientific research, specifically searching for new pulsars. To this end, we also are improving rural teachers' knowledge of the nature of science, the importance of information technology to scientific discovery, and methodologies for incorporating inquiry-based education into the classroom. The PSC hopes to make school science more like the practice of science and to make science fun and interesting for high school students. In 2007, an international team of astronomers received 900 hours of time on the Green Bank Telescope (GBT) during the summer shutdown to search for new pulsars. In conjunction with this group, we applied for and received 300 hours of observing time on the GBT for the PSC students. Around the same time, we were awarded an NSF iTEST grant to fund the Pulsar Search Collaboratory (PSC) project. Over the past year, we have been working with colleagues in the WVU Department of Computer Science to develop a graphical interface through which the students will analyze pulsar search plots (see psrsearch.wvu.edu). We also initiated a robust processing pipeline on a cluster in the WVU Computer Science Department. The PSC started in earnest this summer with a three week workshop in Green Bank where the teachers attended an intensive astronomy mini-course and techniques on introducing astronomy into the classroom. The students joined their teachers for the third week and participated in various activities to teach them about radio astronomy, radio frequency interference, and pulsars.
2009-04-01
An Extensive X-ray Computed Tomography Evaluation of a Fully Penetrated Encapsulated SiC MMC Ballistic Panel by William H. Green and Robert H...Panel William H. Green and Robert H. Carter Weapons and Materials Research Directorate, ARL...PROGRAM ELEMENT NUMBER 2182040 6. AUTHOR(S) William H. Green and Robert H. Carter 5d. PROJECT NUMBER AH80 5e. TASK NUMBER 5f. WORK UNIT
NASA Astrophysics Data System (ADS)
Aktas, Mehmet; Aydin, Galip; Donnellan, Andrea; Fox, Geoffrey; Granat, Robert; Grant, Lisa; Lyzenga, Greg; McLeod, Dennis; Pallickara, Shrideep; Parker, Jay; Pierce, Marlon; Rundle, John; Sayar, Ahmet; Tullis, Terry
2006-12-01
We describe the goals and initial implementation of the International Solid Earth Virtual Observatory (iSERVO). This system is built using a Web Services approach to Grid computing infrastructure and is accessed via a component-based Web portal user interface. We describe our implementations of services used by this system, including Geographical Information System (GIS)-based data grid services for accessing remote data repositories and job management services for controlling multiple execution steps. iSERVO is an example of a larger trend to build globally scalable scientific computing infrastructures using the Service Oriented Architecture approach. Adoption of this approach raises a number of research challenges in millisecond-latency message systems suitable for internet-enabled scientific applications. We review our research in these areas.
Telescopes in Education: the Little Thompson Observatory
NASA Astrophysics Data System (ADS)
Schweitzer, A. E.; Melsheimer, T. T.; Sackett, C.
2001-12-01
The Little Thompson Observatory is believed to be the first observatory built as part of a high school and accessible to other schools remotely, via the Internet. This observatory is the second member of the Telescopes in Education (TIE) project. Construction of the building was done completely by volunteer labor, and first light occurred in May 1999. The observatory is located on the grounds of Berthoud High School in northern Colorado. We are grateful to have received an IDEAS grant to provide teacher training workshops for K-12 schools in Colorado to make use of the observatory, including remote observing from classrooms. Students connect to the observatory over the Internet, and then receive the images back on their local computers. We are honored that a committee of teachers and administrators from the Thompson School district have selected these workshops to count towards Incentive Credits (movement on the salary schedule) because the course meets the criteria: "Learning must be directly transferable to the classroom with students and relate to standards, assessment and/or technology." Also in the past year, our training materials have been shared with NASA Goddard and Howard University, which are working together to develop a similar teacher education program.
The Little Thompson Observatory
NASA Astrophysics Data System (ADS)
Schweitzer, A.; VanLew, K.; Melsheimer, T.; Sackett, C.
2000-12-01
The Little Thompson Observatory is the second member of the Telescopes in Education (TIE) project. The observatory is located on the grounds of Berthoud High School in northern Colorado. The telescope is operational over the Internet, and we are now debugging the software to enable schools to control the telescope from classroom computers and take images. Local schools and youth organizations have prioritized access to the telescope, and there are monthly opportunities for public viewing. In the future, the telescope will be open after midnight to world-wide use by schools following the model of the first TIE observatory, the 24" telescope on Mt. Wilson. The observatory grew out of grassroots support from the local community surrounding Berthoud, Colorado, a town of 3,500 residents. TIE has provided the observatory with a Tinsley 18" Cassegrain telescope on a 10-year loan. The facility has been built with tremendous support from volunteers and the local school district. With funding from an IDEAS grant, we have completed the first teacher training workshops to allow K-12 schools in northern Colorado to make use of the Little Thompson Observatory, including remote observing from classrooms. The workshops were accredited by the school district, and received very favorable reviews.
Infrared Lunar Laser Ranging at Calern : Impact on Lunar Dynamics
NASA Astrophysics Data System (ADS)
Viswanathan, Vishnu; Fienga, Agnes; Manche, Herve; Gastineau, Mickael; Courde, Clement; Torre, Jean Marie; Exertier, Pierre; Laskar, Jacques
2017-04-01
Introduction: Since 2015, in addition to the traditional green (532nm), infrared (1064nm) has been the preferred wavelength for lunar laser ranging at the Calern lunar laser ranging (LLR) site in France. Due to the better atmospheric transmission of IR with respect to Green, nearly 3 times the number of normal points have been obtained in IR than in Green [1]. Dataset: In our study, in addition to the historical data obtained from various other LLR sites, we include the recent IR normal points obtained from Calern over the 1 year time span (2015-2016), constituting about 4.2% of data spread over 46 years of LLR. Near even distribution of data provided by IR on both the spatial and temporal domain, helps us to improve constraints on the internal structure of the Moon modeled within the planetary ephemeris : INPOP [2]. Data reduction: IERS recommended models have been used in the data reduction software GINS (GRGS,CNES) [3]. Constraints provided by GRAIL [4], on the Lunar gravitational potential and Love numbers have been taken into account in the least-square fit procedure. Earth orientation parameters from KEOF series have been used as per a recent study [5]. Results: New estimates on the dynamical parameters of the lunar core will be presented. Acknowledgements: We thank the lunar laser ranging observers at Observatoire de la Côte d'Azur, France, McDonald Observatory, Texas, Haleakala Observatory, Hawaii, and Apache Point Observatory in New Mexico for providing LLR observations that made this study possible. The research described in this abstract was carried out at Geoazur-CNRS, France, as a part of a PhD thesis funded by Observatoire de Paris and French Ministry of Education and Research. References: [1] Clement C. et al. (2016) submitted to A&A [2] Fienga A. et al. (2015) Celest Mech Dyn Astr, 123: 325. doi:10.1007/s10569-015-9639-y [3] Viswanathan V. et al. (2015) EGU, Abstract 18, 13995 [4] Konopliv A. S. et al. (2013) J. Geophys. Res. Planets, 118, 1415-1434, doi:10.1002/jgre.20097 [5] Pavlov, D.A. et al. Celest Mech Dyn Astr (2016) 126: 61. doi:10.1007/s10569-016-9712-1
Astronomy Against Terrorism: an Educational Astronomical Observatory Project in Peru
NASA Astrophysics Data System (ADS)
Ishitsuka, M.; Montes, H.; Kuroda, T.; Morimoto, M.; Ishitsuka, J.
2003-05-01
The Cosmos Coronagraphic Observatory was completely destroyed by terrorists in 1988. In 1995, in coordination with the Minister of Education of Peru, a project to construct a new Educational Astronomical Observatory has been executed. The main purpose of the observatory is to promote an interest in basic space sciences in young students from school to university levels, through basic astronomical studies and observations. The planned observatory will be able to lodge 25 visitors; furthermore an auditorium, a library and a computer room will be constructed to improve the interest of people in astronomy. Two 15-cm refractor telescopes, equipped with a CCD camera and a photometer, will be available for observations. Also a 6-m dome will house a 60-cm class reflector telescope, which will be donated soon, thanks to a fund collected and organized by the Nishi-Harima Astronomical Observatory in Japan. In addition a new modern planetarium donated by the Government of Japan will be installed in Lima, the capital of Peru. These installations will be widely open to serve the requirements of people interested in science.
NASA Astrophysics Data System (ADS)
Beauducel, François; Bosson, Alexis; Randriamora, Frédéric; Anténor-Habazac, Christian; Lemarchand, Arnaud; Saurel, Jean-Marie; Nercessian, Alexandre; Bouin, Marie-Paule; de Chabalier, Jean-Bernard; Clouard, Valérie
2010-05-01
Seismological and Volcanological observatories have common needs and often common practical problems for multi disciplinary data monitoring applications. In fact, access to integrated data in real-time and estimation of measurements uncertainties are keys for an efficient interpretation, but instruments variety, heterogeneity of data sampling and acquisition systems lead to difficulties that may hinder crisis management. In Guadeloupe observatory, we have developed in the last years an operational system that attempts to answer the questions in the context of a pluri-instrumental observatory. Based on a single computer server, open source scripts (Matlab, Perl, Bash, Nagios) and a Web interface, the system proposes: an extended database for networks management, stations and sensors (maps, station file with log history, technical characteristics, meta-data, photos and associated documents); a web-form interfaces for manual data input/editing and export (like geochemical analysis, some of the deformation measurements, ...); routine data processing with dedicated automatic scripts for each technique, production of validated data outputs, static graphs on preset moving time intervals, and possible e-mail alarms; computers, acquisition processes, stations and individual sensors status automatic check with simple criteria (files update and signal quality), displayed as synthetic pages for technical control. In the special case of seismology, WebObs includes a digital stripchart multichannel continuous seismogram associated with EarthWorm acquisition chain (see companion paper Part 1), event classification database, location scripts, automatic shakemaps and regional catalog with associated hypocenter maps accessed through a user request form. This system leads to a real-time Internet access for integrated monitoring and becomes a strong support for scientists and technicians exchange, and is widely open to interdisciplinary real-time modeling. It has been set up at Martinique observatory and installation is planned this year at Montserrat Volcanological Observatory. It also in production at the geomagnetic observatory of Addis Abeba in Ethiopia.
NASA Astrophysics Data System (ADS)
Kärcher, Hans J.; Kunz, Nans; Temi, Pasquale; Krabbe, Alfred; Wagner, Jörg; Süß, Martin
2014-07-01
The original pointing accuracy requirement of the Stratospheric Observatory for Infrared Astronomy SOFIA was defined at the beginning of the program in the late 1980s as very challenging 0.2 arcsec rms. The early science flights of the observatory started in December 2010 and the observatory has reached in the mean time nearly 0.7 arcsec rms, which is sufficient for most of the SOFIA science instruments. NASA and DLR, the owners of SOFIA, are planning now a future 4 year program to bring the pointing down to the ultimate 0.2 arcsec rms. This may be the right time to recall the history of the pointing requirement and its verification and the possibility of its achievement via early computer models and wind tunnel tests, later computer aided end-to-end simulations up to the first commissioning flights some years ago. The paper recollects the tools used in the different project phases for the verification of the pointing performance, explains the achievements and may give hints for the planning of the upcoming final pointing improvement phase.
Lidar Atmospheric Observatory in the Canadian Arctic
NASA Technical Reports Server (NTRS)
Ulitsky, Arkady; Wang, Tin-Yu; Flood, Martin; Smith, Brent
1992-01-01
During the last decade there have been growing concerns about a broad variety of atmospheric properties. Among these, a depletion of the stratospheric ozone layer has attracted considerable attention from the general public, politicians and scientists due to its vital impact for the entire global biosphere. One of the major warning signs was the discovery of the 'ozone hole' in the Antarctic region where the concentration of the ozone in the stratosphere was significantly reduced. At present the stratospheric ozone layer in this region is being continuously monitored by groups of scientists from around the world and numerous observations of the ozone layer on the global scale have clearly demonstrated the process of ozone depletion. Recent observations by NASA have shown significant depletion in the Arctic region. This paper provides an initial description of two lidars that are planned to be installed in a new observatory for atmospheric studies in the Canadian Arctic. This observatory is being constructed under the supervision of the Atmospheric Environment Services (AES) of Canada as a part of Green Plan - an initiative of the Federal Government of Canada. The station is located at Eureka on Ellesmere Island at a latitude of 80 degrees N and a longitude of 86 degrees W.
2017-12-08
NASA image acquired August 29, 2012 1:57 a.m EDT Annotated view here: bit.ly/RsFT9Y Hurricane Isaac lit up by moonlight as it spins over the city of New Orleans, La. at 1:57 am central daylight savings time the morning of August 29, 2012. The Suomi National Polar-orbiting Partnership (NPP) satellite captured these images with its Visible Infrared Imaging Radiometer Suite (VIIRS). The "day-night band" of VIIRS detects light in a range of wavelengths from green to near-infrared and uses light intensification to enable the detection of dim signals. Suomi NPP is the result of a partnership between NASA, the National Oceanic and Atmospheric Administration and the Department of Defense. Image Credit: NASA/NOAA, Earth Observatory NASA Earth Observatory image by Jesse Allen and Robert Simmon, using VIIRS Day Night Band data. Credit: NASA Earth Observatory NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram
EPA and GSA Webinar: E Scrap Management, Computers for Learning and the Federal Green Challenge
EPA and the General Services Administration (GSA) are hosting a webinar on May 2, 2018. Topics will include policies and procedures on E Scrap management, a review of the Computers For Leaning Program, and benefits of joining the Federal Green Challenge.
NASA Astrophysics Data System (ADS)
Lockman, F. J.; Heatherly, S. A.
2001-05-01
Most K-12 teachers of science have never actually done research, and this creates considerable confusion and misunderstanding about the nature of science. For more than 10 years the NRAO at Green Bank has conducted programs of teacher training, funded by the NSF, which provide a research experience in radio astronomy that can be generalized and applied in the classroom. Our program is under the direction of educators from the NRAO and WVU, but uses the unique facilities of the Observatory and the active participation of its scientific staff. Evaluations have shown that the two-week programs are effective in making significant, positive changes in attitude and understanding of the participants. We are in the process of expanding our educational activities so that every student in the region and the State will be able to participate in at least one program at the Observatory before they graduate from high school.
Chandra X-Ray Observatory Image of Cassiopeia A
NASA Technical Reports Server (NTRS)
1999-01-01
This is an extraordinary first image from the Chandra X-Ray Observatory (CXO), the supernova remnant Cassiopeia A, tracing the aftermath of a gigantic stellar explosion in such sturning detail that scientists can see evidence of what may be a neutron star or black hole near the center. The red, green, and blue regions in this image of the supernova remnant Cassiopeia A show where the intensity of low, medium, and high energy X-rays, respectively, is greatest. The red material on the left outer edge is enriched in iron, whereas the bright greenish white region on the low left is enriched in silicon and sulfur. In the blue region on the right edge, low and medium energy X-rays have been filtered out by a cloud of dust and gas in the remnant . The image was made with the CXO's Advanced Charged-Coupled Device (CCD) Imaging Spectrometer (ACIS). Photo credit: NASA/CXC/SAO/Rutgers/J.Hughes
Real-Time Thermal Mapping for Heat & Cool Archipelagos of Bengaluru, India
NASA Astrophysics Data System (ADS)
Gopinath, Rajesh; Banerjee, Aditya; Sachin, S.; Tiwari, Prakhar; Wilson, Sunny
2017-12-01
Blessed with a salubrious climate, the city of Bengaluru over the past few decades has constantly witnessed thermal discomfort owing to several Urban Heat islands that have mushroomed within the city. The subsequent increase in builtup area, consequent loss of productive agricultural lands/green zones, encroachment of surface water bodies coupled with the ill-preparedness of decision makers to handle the demand for land have invariably crumbled the natural micro-climate of the city. In this present research, an attempt has been made to detect the distribution of Urban Heat Islands in Bengaluru City by conducting real-time survey at 100 observatories marked across the entire urban & rural locations; with thermohygrometers as per the W.M.O. guidelines. The study confirmed the violation of the Human Thermal Comfort Range in 9, 83, 98, 99, 98 and 80 observatories for the monitoring at 6 AM, 9 AM, 12 PM, 3 PM, 6 PM and 9 PM respectively.
History of Chandra X-Ray Observatory
1999-08-01
This is an extraordinary first image from the Chandra X-Ray Observatory (CXO), the supernova remnant Cassiopeia A, tracing the aftermath of a gigantic stellar explosion in such sturning detail that scientists can see evidence of what may be a neutron star or black hole near the center. The red, green, and blue regions in this image of the supernova remnant Cassiopeia A show where the intensity of low, medium, and high energy X-rays, respectively, is greatest. The red material on the left outer edge is enriched in iron, whereas the bright greenish white region on the low left is enriched in silicon and sulfur. In the blue region on the right edge, low and medium energy X-rays have been filtered out by a cloud of dust and gas in the remnant . The image was made with the CXO's Advanced Charged-Coupled Device (CCD) Imaging Spectrometer (ACIS). Photo credit: NASA/CXC/SAO/Rutgers/J.Hughes
Education Potential of the National Virtual Observatory
NASA Astrophysics Data System (ADS)
Christian, Carol
2006-12-01
Research in astronomy is blossoming with the availability of sophisticated instrumentation and tools aimed at breakthroughs in our understanding of the physical universe. Researchers can take advantage of the astronomical infrastructure, the National Virtual Observatory (NVO), for their investigations. . As well, data and tools available to the public are increasing through the distributed resources of observatories, academic institutions, computing facilities and educational organizations. Because Astronomy holds the public interest through engaging content and striking a cord with fundamental questions of human interest, it is a perfect context for science and technical education. Through partnerships we are cultivating, the NVO can be tuned for educational purposes.
Construction/Application of the Internet Observatories in Japan
NASA Astrophysics Data System (ADS)
Satoh, T.; Tsubota, Y.; Matsumoto, N.; Takahashi, N.
2000-05-01
We have successfully built two Internet Observatories in Japan: one at Noda campus of the Science University of Tokyo and another at Hiyoshi campus of the Keio Senior High School. Both observatories are equipped with a computerized Meade LX-200 telescope (8" tube at the SUT site and 12" at the Keio site) with a CCD video camera inside the sliding-roof type observatory. Each observatory is controlled by two personal computer: one controls almost everything, including the roof, the telescope, and the camera, while another is dedicated to encode the real-time picture from the CCD video camera into the RealVideo format for live broadcasting. A user can operate the observatory through the web-based interface and can enjoy the real-time picture of the objects via the RealPlayer software. The administrator can run a sequence of batch commands with which no human interaction is needed from the beginning to the end of an observation. Although our observatories are primarily for educational purposes, this system can easily be converted to a signal-triggered one which may be very useful to observe transient phenomena, such as afterglows of gamma-ray bursts. The most remarkable feature of our observatories is that it is very inexpensive (it costs only a few tens of grands). We'll report details of the observatories in the poster, and at the same time, will demonstrate operating the observatories using an internet-connected PC from the meeting site. This work has been supported through the funding from the Telecommunicaitons Advancement Foundation for FY 1998 and 1999.
Reexamination of the Coronal Index of Solar Activity
2005-08-25
data with measurements made at Pic du Midi and Arosa . The resultant 1939-1992 CI had the interesting property that its value at the peak of the 11-year...1939 observation of the coronal emission line at 5303 A during when Waldmeier initiated green line measurements at Arosa the total solar eclipse of 7...limitations since the values obtained at differ- and Pic du Midi and Pic du Midi and Arosa to extend ent observatories depend on: (1) the accuracy of the the
47 CFR 15.712 - Interference protection requirements.
Code of Federal Regulations, 2010 CFR
2010-10-01
...′04″ N. Arecibo Observatory 066°45′11″ W 18°20′46″ N. Green Bank Telescope (GBT) 079°50′24″ W 38°25′59... meters 14.4 0.74 (b) Translator receive sites and cable headends. For translator receive sites and cable.... (2) The Table Mountain Radio Receiving Zone (TMRZ) at 40°07′50″ N and 105°15′40″ W. (3) The following...
Astronomical virtual observatory and the place and role of Bulgarian one
NASA Astrophysics Data System (ADS)
Petrov, Georgi; Dechev, Momchil; Slavcheva-Mihova, Luba; Duchlev, Peter; Mihov, Bojko; Kochev, Valentin; Bachev, Rumen
2009-07-01
Virtual observatory could be defined as a collection of integrated astronomical data archives and software tools that utilize computer networks to create an environment in which research can be conducted. Several countries have initiated national virtual observatory programs that combine existing databases from ground-based and orbiting observatories, scientific facility especially equipped to detect and record naturally occurring scientific phenomena. As a result, data from all the world's major observatories will be available to all users and to the public. This is significant not only because of the immense volume of astronomical data but also because the data on stars and galaxies has been compiled from observations in a variety of wavelengths-optical, radio, infrared, gamma ray, X-ray and more. In a virtual observatory environment, all of this data is integrated so that it can be synthesized and used in a given study. During the autumn of the 2001 (26.09.2001) six organizations from Europe put the establishment of the Astronomical Virtual Observatory (AVO)-ESO, ESA, Astrogrid, CDS, CNRS, Jodrell Bank (Dolensky et al., 2003). Its aims have been outlined as follows: - To provide comparative analysis of large sets of multiwavelength data; - To reuse data collected by a single source; - To provide uniform access to data; - To make data available to less-advantaged communities; - To be an educational tool. The Virtual observatory includes: - Tools that make it easy to locate and retrieve data from catalogues, archives, and databases worldwide; - Tools for data analysis, simulation, and visualization; - Tools to compare observations with results obtained from models, simulations and theory; - Interoperability: services that can be used regardless of the clients computing platform, operating system and software capabilities; - Access to data in near real-time, archived data and historical data; - Additional information - documentation, user-guides, reports, publications, news and so on. This large growth of astronomical data and the necessity of an easy access to those data led to the foundation of the International Virtual Observatory Alliance (IVOA). IVOA was formed in June 2002. By January 2005, the IVOA has grown to include 15 funded VO projects from Australia, Canada, China, Europe, France, Germany, Hungary, India, Italy, Japan, Korea, Russia, Spain, the United Kingdom, and the United States. At the time being Bulgaria is not a member of European Astronomical Virtual Observatory and as the Bulgarian Virtual Observatory is not a legal entity, we are not members of IVOA. The main purpose of the project is Bulgarian Virtual Observatory to join the leading virtual astronomical institutions in the world. Initially the Bulgarian Virtual Observatory will include: - BG Galaxian virtual observatory; - BG Solar virtual observatory; - Department Star clusters of IA, BAS; - WFPDB group of IA, BAS. All available data will be integrated in the Bulgarian centers of astronomical data, conducted by the Wide Field Plate Archive data centre. For the above purpose POSTGRESQL or/and MySQL will be installed on the server of BG-VO and SAADA tools, ESO-MEX or/and DAL ToolKit to transform our FITS files in standard format for VO-tools. A part of the participants was acquainted with the principles of these products during the "Days of virtual observatory in Sofia" January, 2008.
Banzato, T; Selleri, P; Veladiano, I A; Zotti, A
2013-12-01
Contrast-enhanced computed tomographic studies of the coelomic cavity in four green iguanas, four black and white tegus and four bearded dragons were performed using a conventional CT scanner. Anatomical reference cross sections were obtained from four green iguana, four black and white tegu and six bearded dragon cadavers; the specimens were stored in a -20°C freezer for 24 h then sliced into 5-mm intervals. The frozen sections were cleaned with water and photographed on both sides. The individual anatomical structures were identified by means of the available literature; these were labelled first on the anatomical images and then matched to the corresponding computed tomography images. The results provide an atlas of the normal cross-sectional and computed tomographic anatomy of the coelomic cavity in the green iguana, the black and white tegu and the bearded dragon, which is useful in the interpretation of any imaging modality. © 2013 Blackwell Verlag GmbH.
A large-scale solar dynamics observatory image dataset for computer vision applications.
Kucuk, Ahmet; Banda, Juan M; Angryk, Rafal A
2017-01-01
The National Aeronautics Space Agency (NASA) Solar Dynamics Observatory (SDO) mission has given us unprecedented insight into the Sun's activity. By capturing approximately 70,000 images a day, this mission has created one of the richest and biggest repositories of solar image data available to mankind. With such massive amounts of information, researchers have been able to produce great advances in detecting solar events. In this resource, we compile SDO solar data into a single repository in order to provide the computer vision community with a standardized and curated large-scale dataset of several hundred thousand solar events found on high resolution solar images. This publicly available resource, along with the generation source code, will accelerate computer vision research on NASA's solar image data by reducing the amount of time spent performing data acquisition and curation from the multiple sources we have compiled. By improving the quality of the data with thorough curation, we anticipate a wider adoption and interest from the computer vision to the solar physics community.
2016-01-07
Astronomers have made the most detailed study yet of an extremely massive young galaxy cluster using three of NASA's Great Observatories. This multi-wavelength image shows this galaxy cluster, called IDCS J1426.5+3508 (IDCS 1426 for short), in X-rays recorded by the Chandra X-ray Observatory in blue, visible light observed by the Hubble Space Telescope in green, and infrared light detected by the Spitzer Space Telescope in red. This rare galaxy cluster, which is located 10 billion light-years from Earth, is almost as massive as 500 trillion suns. This object has important implications for understanding how such megastructures formed and evolved early in the universe. The light astronomers observed from IDCS 1426 began its journey to Earth when the universe was less than a third of its current age. It is the most massive galaxy cluster detected at such an early time. First discovered by the Spitzer Space Telescope in 2012, IDCS 1426 was then observed using the Hubble Space Telescope and the Keck Observatory to determine its distance. Observations from the Combined Array for Millimeter-wave Astronomy indicated it was extremely massive. New data from the Chandra X-ray Observatory confirm the galaxy cluster's mass and show that about 90 percent of this mass is in the form of dark matter -- the mysterious substance that has so far been detected only through its gravitational pull on normal matter composed of atoms. http://photojournal.jpl.nasa.gov/catalog/PIA20063
Ny-Alesund Geodetic Observatory
NASA Technical Reports Server (NTRS)
Sieber, Moritz
2013-01-01
In 2012 the 20-m telescope at Ny-Alesund, Svalbard, operated by the Norwegian Mapping Authority (NMA), took part in 163 out of 168 scheduled sessions of the IVS program. Since spring, all data was transferred by network, and the receiver monitoring computer was replaced by a bus-coupler. In autumn, the NMA received building permission for a new observatory from the Governor of Svalbard. The bidding process and first construction work for the infrastructure will start in 2013.
Utilizing Internet Technologies in Observatory Control Systems
NASA Astrophysics Data System (ADS)
Cording, Dean
2002-12-01
The 'Internet boom' of the past few years has spurred the development of a number of technologies to provide services such as secure communications, reliable messaging, information publishing and application distribution for commercial applications. Over the same period, a new generation of computer languages have also developed to provide object oriented design and development, improved reliability, and cross platform compatibility. Whilst the business models of the 'dot.com' era proved to be largely unviable, the technologies that they were based upon have survived and have matured to the point were they can now be utilized to build secure, robust and complete observatory control control systems. This paper will describe how Electro Optic Systems has utilized these technologies in the development of its third generation Robotic Observatory Control System (ROCS). ROCS provides an extremely flexible configuration capability within a control system structure to provide truly autonomous robotic observatory operation including observation scheduling. ROCS was built using Internet technologies such as Java, Java Messaging Service (JMS), Lightweight Directory Access Protocol (LDAP), Secure Sockets Layer (SSL), eXtendible Markup Language (XML), Hypertext Transport Protocol (HTTP) and Java WebStart. ROCS was designed to be capable of controlling all aspects of an observatory and be able to be reconfigured to handle changing equipment configurations or user requirements without the need for an expert computer programmer. ROCS consists of many small components, each designed to perform a specific task, with the configuration of the system specified using a simple meta language. The use of small components facilitates testing and makes it possible to prove that the system is correct.
A USB 2.0 computer interface for the UCO/Lick CCD cameras
NASA Astrophysics Data System (ADS)
Wei, Mingzhi; Stover, Richard J.
2004-09-01
The new UCO/Lick Observatory CCD camera uses a 200 MHz fiber optic cable to transmit image data and an RS232 serial line for low speed bidirectional command and control. Increasingly RS232 is a legacy interface supported on fewer computers. The fiber optic cable requires either a custom interface board that is plugged into the mainboard of the image acquisition computer to accept the fiber directly or an interface converter that translates the fiber data onto a widely used standard interface. We present here a simple USB 2.0 interface for the UCO/Lick camera. A single USB cable connects to the image acquisition computer and the camera's RS232 serial and fiber optic cables plug into the USB interface. Since most computers now support USB 2.0 the Lick interface makes it possible to use the camera on essentially any modern computer that has the supporting software. No hardware modifications or additions to the computer are needed. The necessary device driver software has been written for the Linux operating system which is now widely used at Lick Observatory. The complete data acquisition software for the Lick CCD camera is running on a variety of PC style computers as well as an HP laptop.
PAPER: The Precision Array To Probe The Epoch Of Reionization
NASA Astrophysics Data System (ADS)
Backer, Donald C.; Parsons, A.; Bradley, R.; Parashare, C.; Gugliucci, N.; Mastrantonio, E.; Herne, D.; Lynch, M.; Wright, M.; Werhimer, D.; Carilli, C.; Datta, A.; Aguirre, J.
2007-12-01
The Precision Array to Probe the Epoch of Reionization (PAPER) is an experiment that is being designed to detect the faint HI signal from the epoch of reionization. Our instrumentation goals include: the design and building of dipole elements that are optimized for operation from 120-190 MHz with a clean beam response; amplifiers and receivers with good impedance match and overall flat gain response over a large bandpass; and an FPGA correlator capable of producing full Stokes products for the array. The array is being built and evaluated in stages at the Green Bank Observatory in West Virginia with deployment of the full instrument in Western Australia. We present results from an eight-station deployment in Green Bank and four-station deployment in Western Australia, including phase and amplitude calibration, RFI mitigation and removal, full sky maps, and wide-field snapshot imaging. We have discovered new ways to improve our system's stability and sensitivity from these early experiments, and are applying these concepts to a 16-element array in Green Bank in early 2008 and a 32-element array in Western Australia later in 2008.
Development of a Compact Eleven Feed Cryostat for the Patriot 12-m Antenna System
NASA Technical Reports Server (NTRS)
Beaudoin, Christopher; Kildal, Per-Simon; Yang, Jian; Pantaleev, Miroslav
2010-01-01
The Eleven antenna has constant beam width, constant phase center location, and low spillover over a decade bandwidth. Therefore, it can feed a reflector for high aperture efficiency (also called feed efficiency). It is equally important that the feed efficiency and its subefficiencies not be degraded significantly by installing the feed in a cryostat. The MIT Haystack Observatory, with guidance from Onsala Space Observatory and Chalmers University, has been working to integrate the Eleven antenna into a compact cryostat suitable for the Patriot 12-m antenna. Since the analysis of the feed efficiencies in this presentation is purely computational, we first demonstrate the validity of the computed results by comparing them to measurements. Subsequently, we analyze the dependence of the cryostat size on the feed efficiencies, and, lastly, the Patriot 12-m subreflector is incorporated into the computational model to assess the overall broadband efficiency of the antenna system.
NASA Astrophysics Data System (ADS)
Noumaru, Junichi; Kawai, Jun A.; Schubert, Kiaina; Yagi, Masafumi; Takata, Tadafumi; Winegar, Tom; Scanlon, Tim; Nishida, Takuhiro; Fox, Camron; Hayasaka, James; Forester, Jason; Uchida, Kenji; Nakamura, Isamu; Tom, Richard; Koura, Norikazu; Yamamoto, Tadahiro; Tanoue, Toshiya; Yamada, Toru
2008-07-01
Subaru Telescope has recently replaced most equipment of Subaru Telescope Network II with the new equipment which includes 124TB of RAID system for data archive. Switching the data storage from tape to RAID enables users to access the data faster. The STN-III dropped some important components of STN-II, such as supercomputers, development & testing subsystem for Subaru Observation Control System, or data processing subsystem. On the other hand, we invested more computers to the remote operation system. Thanks to IT innovations, our LAN as well as the network between Hilo and summit were upgraded to gigabit network at the similar or even reduced cost from the previous system. As the result of the redesigning of the computer system by more focusing on the observatory operation, we greatly reduced the total cost for computer rental, purchase and maintenance.
NASA Technical Reports Server (NTRS)
Williams, Jessica L.; Bhat, Ramachandra S.; You, Tung-Han
2012-01-01
The Soil Moisture Active Passive (SMAP) mission will perform soil moisture content and freeze/thaw state observations from a low-Earth orbit. The observatory is scheduled to launch in October 2014 and will perform observations from a near-polar, frozen, and sun-synchronous Science Orbit for a 3-year data collection mission. At launch, the observatory is delivered to an Injection Orbit that is biased below the Science Orbit; the spacecraft will maneuver to the Science Orbit during the mission Commissioning Phase. The delta V needed to maneuver from the Injection Orbit to the Science Orbit is computed statistically via a Monte Carlo simulation; the 99th percentile delta V (delta V99) is carried as a line item in the mission delta V budget. This paper details the simulation and analysis performed to compute this figure and the delta V99 computed per current mission parameters.
NASA Astrophysics Data System (ADS)
Ballmer, S.; Wolfe, C. J.; Okubo, P.; Haney, M. M.; Thurber, C. H.
2011-12-01
Green's functions calculated with ambient seismic noise may aid in volcano research and monitoring. The continuous character of ambient seismic noise and hence of the reconstructed Green's functions has enabled measurements of short-term (~days) temporal perturbations in seismic velocities. Very small but clear velocity decreases prior to some volcanic eruptions have been documented and motivate our present study. We apply this method to Hawaiian volcanoes using data from the USGS Hawaiian Volcano Observatory (HVO) seismic network. In order to obtain geologically relevant and reliable results, stable Green's functions need to be recovered from the ambient noise. Station timing problems, changes in noise source directivity, as well as changes in the source's spectral content are known biases that critically affect the Green's functions' stability and hence need to be considered. Here we show that volcanic tremor is a potential additional bias. During the time period of our study (2007-present), we find that volcanic tremor is a common feature in the HVO seismic data. Pu'u O'o tremor is continuously present before a dike intrusion into Kilauea's east rift zone in June 2007 and Halema'uma'u tremor occurs before and during resumed Kilauea summit activity from early 2008 and onward. For the frequency band considered (0.1-0.9 Hz), we find that these active tremor sources can drastically modify the recovered Green's functions for station pairs on the entire island at higher (> 0.5 Hz) frequencies, although the effect of tremor appears diminished at lower frequencies. In this presentation, we perform measurements of temporal velocity changes using ambient noise Green's functions and explore how volcanic tremor affects the results. Careful quality assessment of reconstructed Green's functions appears to be essential for the desired high precision measurements.
Larson, Nels R. [Pacific Northwest Laboratory (PNNL), Richland, WA (USA); Michalsky, Joseph J. [Atmospheric Sciences Research Center, Albany, NY (USA); LeBaron, Brock A. [Utah Bureau of Air Quality, Salt Lake City, Utah (USA)
2012-01-01
Surface measurements of solar irradiance of the atmosphere were made by a multipurpose computer-controlled scanning photometer at the Rattlesnake Mountain Observatory in eastern Washington. The observatory is located at 46.4° N, 119.6° W at an elevation of 1088 m above mean sea level. The photometer measures the attenuation of direct solar radiation for different wavelengths using 12 filters. Five of these filters (i.e., at 428 nm, 486 nm, 535 nm, 785 nm, and 1010 nm, with respective half-power widths of 2, 2, 3, 18, and 28 nm) are suitable for monitoring variations in the total optical depth of the atmosphere.
Invasive European green crab (Carcinus maenus) populations have exploded with devastating losses to Maine’s intertidal resources including soft-shell clams, eelgrass beds, and salt marshes. This project quantified the green crab abundance in three different marsh locations ...
Data Processing Center of Radioastron Project: 3 years of operation.
NASA Astrophysics Data System (ADS)
Shatskaya, Marina
ASC DATA PROCESSING CENTER (DPC) of Radioastron Project is a fail-safe complex centralized system of interconnected software/ hardware components along with organizational procedures. Tasks facing of the scientific data processing center are organization of service information exchange, collection of scientific data, storage of all of scientific data, data science oriented processing. DPC takes part in the informational exchange with two tracking stations in Pushchino (Russia) and Green Bank (USA), about 30 ground telescopes, ballistic center, tracking headquarters and session scheduling center. Enormous flows of information go to Astro Space Center. For the inquiring of enormous data volumes we develop specialized network infrastructure, Internet channels and storage. The computer complex has been designed at the Astro Space Center (ASC) of Lebedev Physical Institute and includes: - 800 TB on-line storage, - 2000 TB hard drive archive, - backup system on magnetic tapes (2000 TB); - 24 TB redundant storage at Pushchino Radio Astronomy Observatory; - Web and FTP servers, - DPC management and data transmission networks. The structure and functions of ASC Data Processing Center are fully adequate to the data processing requirements of the Radioastron Mission and has been successfully confirmed during Fringe Search, Early Science Program and first year of Key Science Program.
NASA Astrophysics Data System (ADS)
McGill, P.; Neuhauser, D.; Romanowicz, B.
2008-12-01
The Monterey Ocean-Bottom Broadband (MOBB) seismic station was installed in April 2003, 40 km offshore from the central coast of California at a seafloor depth of 1000 m. It comprises a three-component broadband seismometer system (Guralp CMG-1T), installed in a hollow PVC caisson and buried under the seafloor; a current meter; and a differential pressure gauge. The station has been operating continuously since installation with no connection to the shore. Three times each year, the station is serviced with the aid of a Remotely Operated Vehicle (ROV) to change the batteries and retrieve the seismic data. In February 2009, the MOBB system will be connected to the Monterey Accelerated Research System (MARS) seafloor cabled observatory. The NSF-funded MARS observatory comprises a 52 km electro-optical cable that extends from a shore facility in Moss Landing out to a seafloor node in Monterey Bay. Once installation is completed in November 2008, the node will provide power and data to as many as eight science experiments through underwater electrical connectors. The MOBB system is located 3 km from the MARS node, and the two will be connected with an extension cable installed by an ROV with the aid of a cable-laying toolsled. The electronics module in the MOBB system is being refurbished to support the connection to the MARS observatory. The low-power autonomous data logger has been replaced with a PC/104 computer stack running embedded Linux. This new computer will run an Object Ring Buffer (ORB), which will collect data from the various MOBB sensors and forward it to another ORB running on a computer at the MARS shore station. There, the data will be archived and then forwarded to a third ORB running at the UC Berkeley Seismological Laboratory. Timing will be synchronized among MOBB's multiple acquisition systems using NTP, GPS clock emulation, and a precise timing signal from the MARS cable. The connection to the MARS observatory will provide real-time access to the MOBB data and eliminate the need for frequent servicing visits. The new system uses off-the-shelf hardware and open-source software, and will serve as a prototype for future instruments connected to seafloor cabled observatories.
NASA Astrophysics Data System (ADS)
Hanisch, R. J.
2014-11-01
The concept of the Virtual Observatory arose more-or-less simultaneously in the United States and Europe circa 2000. Ten pages of Astronomy and Astrophysics in the New Millennium: Panel Reports (National Academy Press, Washington, 2001), that is, the detailed recommendations of the Panel on Theory, Computation, and Data Exploration of the 2000 Decadal Survey in Astronomy, are dedicated to describing the motivation for, scientific value of, and major components required in implementing the National Virtual Observatory. European initiatives included the Astrophysical Virtual Observatory at the European Southern Observatory, the AstroGrid project in the United Kingdom, and the Euro-VO (sponsored by the European Union). Organizational/conceptual meetings were held in the US at the California Institute of Technology (Virtual Observatories of the Future, June 13-16, 2000) and at ESO Headquarters in Garching, Germany (Mining the Sky, July 31-August 4, 2000; Toward an International Virtual Observatory, June 10-14, 2002). The nascent US, UK, and European VO projects formed the International Virtual Observatory Alliance (IVOA) at the June 2002 meeting in Garching, with yours truly as the first chair. The IVOA has grown to a membership of twenty-one national projects and programs on six continents, and has developed a broad suite of data access protocols and standards that have been widely implemented. Astronomers can now discover, access, and compare data from hundreds of telescopes and facilities, hosted at hundreds of organizations worldwide, stored in thousands of databases, all with a single query.
curriculum for its course Physics In and Through Cosmology. The Distributed Observatory aims to become the world's largest cosmic ray telescope, using the distributed sensing and computing power of the world's cell phones. Modeled after the distributed computing efforts of SETI@Home and Folding@Home, the
NASA Technical Reports Server (NTRS)
Harman, R.; Blejer, D.
1990-01-01
The requirements and mathematical specifications for the Gamma Ray Observatory (GRO) Dynamics Simulator are presented. The complete simulator system, which consists of the profie subsystem, simulation control and input/output subsystem, truth model subsystem, onboard computer model subsystem, and postprocessor, is described. The simulator will be used to evaluate and test the attitude determination and control models to be used on board GRO under conditions that simulate the expected in-flight environment.
2015-07-08
Flaring, active regions of our sun are highlighted in this image combining observations from several telescopes. High-energy X-rays from NASA's Nuclear Spectroscopic Telescope Array (NuSTAR) are shown in blue; low-energy X-rays from Japan's Hinode spacecraft are green; and extreme ultraviolet light from NASA's Solar Dynamics Observatory (SDO) is yellow and red. All three telescopes captured their solar images around the same time on April 29, 2015. The NuSTAR image is a mosaic made from combining smaller images. The active regions across the sun's surface contain material heated to several millions of degrees. The blue-white areas showing the NuSTAR data pinpoint the most energetic spots. During the observations, microflares went off, which are smaller versions of the larger flares that also erupt from the sun's surface. The microflares rapidly release energy and heat the material in the active regions. NuSTAR typically stares deeper into the cosmos to observe X-rays from supernovas, black holes and other extreme objects. But it can also look safely at the sun and capture images of its high-energy X-rays with more sensitivity than before. Scientists plan to continue to study the sun with NuSTAR to learn more about microflares, as well as hypothesized nanoflares, which are even smaller. In this image, the NuSTAR data shows X-rays with energies between 2 and 6 kiloelectron volts; the Hinode data, which is from the X-ray Telescope instrument, has energies of 0.2 to 2.4 kiloelectron volts; and the Solar Dynamics Observatory data, taken using the Atmospheric Imaging Assembly instrument, shows extreme ultraviolet light with wavelengths of 171 and 193 Angstroms. Note the green Hinode image frame edge does not extend as far as the SDO ultraviolet image, resulting in the green portion of the image being truncated on the right and left sides. http://photojournal.jpl.nasa.gov/catalog/PIA19821
Efficient method for computing the electronic transport properties of a multiterminal system
NASA Astrophysics Data System (ADS)
Lima, Leandro R. F.; Dusko, Amintor; Lewenkopf, Caio
2018-04-01
We present a multiprobe recursive Green's function method to compute the transport properties of mesoscopic systems using the Landauer-Büttiker approach. By introducing an adaptive partition scheme, we map the multiprobe problem into the standard two-probe recursive Green's function method. We apply the method to compute the longitudinal and Hall resistances of a disordered graphene sample, a system of current interest. We show that the performance and accuracy of our method compares very well with other state-of-the-art schemes.
Telescopes in Education: the Little Thompson Observatory
NASA Astrophysics Data System (ADS)
Schweitzer, A. E.; Melsheimer, T. T.
2002-12-01
The Little Thompson Observatory is the first community-built observatory that is part of a high school and accessible to other schools remotely, via the Internet. This observatory is the second member of the Telescopes in Education (TIE) project. Construction of the building was done completely by volunteer labor, and first light occurred in May 1999. The observatory is located on the grounds of Berthoud High School in northern Colorado. We are grateful to have received an IDEAS grant to provide teacher training workshops for K-12 schools to make use of the observatory, including remote observing from classrooms. Students connect to the observatory over the Internet, and then receive the images back on their local computers. A committee of teachers and administrators from the Thompson School District have selected these workshops to count towards Incentive Credits (movement on the salary schedule) because the course meets the criteria: "Learning must be directly transferable to the classroom with students and relate to standards, assessment and/or technology." In addition, this past summer our program became an accredited course by Colorado State University. Our next project is to partner with the Discovery Center Science Museum and Colorado State University to provide additional teacher education programs. Our training materials have also been shared with TIE/Mt. Wilson, NASA Goddard and Howard University, which are working together to develop a similar teacher education program.
Telescopes in Education: the Little Thompson Observatory
NASA Astrophysics Data System (ADS)
Schweitzer, A. E.; Melsheimer, T. T.
2003-05-01
The Little Thompson Observatory is the first community-built observatory that is part of a high school and accessible to other schools remotely, via the Internet. This observatory is the second member of the Telescopes in Education (TIE) project. Construction of the building was done completely by volunteer labor, and first light occurred in May 1999. The observatory is located on the grounds of Berthoud High School in northern Colorado. We are grateful to have received an IDEAS grant to provide teacher training workshops for K-12 schools to make use of the observatory, including remote observing from classrooms. Students connect to the observatory over the Internet, and then receive the images back on their local computers. A committee of teachers and administrators from the Thompson School District have selected these workshops to count towards Incentive Credits (movement on the salary schedule) because the course meets the criteria: "Learning must be directly transferable to the classroom with students and relate to standards, assessment and/or technology." In addition, this past summer our program became an accredited course by Colorado State University. Our next project is to partner with the Discovery Center Science Museum and Colorado State University to provide additional teacher education programs. Our training materials have also been shared with TIE/Mt. Wilson, NASA Goddard and Howard University, which are working together to develop a similar teacher education program.
Telescopes in Education: the Little Thompson Observatory
NASA Astrophysics Data System (ADS)
Schweitzer, A.; Vanlew, K.; Melsheimer, T.; Melsheimer, L.; Rideout, C.; Patterson, T.
1997-12-01
A second observatory of the Telescopes in Education (TIE) project is in the planning stages, with hopes to be in use by fall 1998. The Little Thompson Observatory will be located adjacent to Berthoud High School in northern Colorado. TIE has offered the observatory a Tinsley 18" Cassegrain telescope on a 10-year loan. Local schools and youth organizations will have prioritized access to the telescope until midnight; after that, the telescope will be open to world-wide use by schools via the Internet. The first TIE observatory is a 24" telescope on Mt. Wilson, already booked through July 1998. That telescope has been in use every clear night for the past four years by up to 50 schools per month. Students remotely control the telescope over the Internet, and then receive the images on their local computers. The estimated cost of the Little Thompson Observatory is roughly \\170,000. However, donations of labor and materials have reduced the final price tag closer to \\40,000. Habitat for Humanity is organized to construct the dome, classrooms, and other facilities. Tom and Linda Melsheimer, who developed the remote telescope control system for the University of Denver's Mount Evans Observatory, are donating a similar control system. The formally-trained, all-volunteer staff will be comprised of local residents, teachers and amateur astronomers. Utilities and Internet access will be provided by the Thompson School District.
Zhang, Yong; Otani, Akihito; Maginn, Edward J
2015-08-11
Equilibrium molecular dynamics is often used in conjunction with a Green-Kubo integral of the pressure tensor autocorrelation function to compute the shear viscosity of fluids. This approach is computationally expensive and is subject to a large amount of variability because the plateau region of the Green-Kubo integral is difficult to identify unambiguously. Here, we propose a time decomposition approach for computing the shear viscosity using the Green-Kubo formalism. Instead of one long trajectory, multiple independent trajectories are run and the Green-Kubo relation is applied to each trajectory. The averaged running integral as a function of time is fit to a double-exponential function with a weighting function derived from the standard deviation of the running integrals. Such a weighting function minimizes the uncertainty of the estimated shear viscosity and provides an objective means of estimating the viscosity. While the formal Green-Kubo integral requires an integration to infinite time, we suggest an integration cutoff time tcut, which can be determined by the relative values of the running integral and the corresponding standard deviation. This approach for computing the shear viscosity can be easily automated and used in computational screening studies where human judgment and intervention in the data analysis are impractical. The method has been applied to the calculation of the shear viscosity of a relatively low-viscosity liquid, ethanol, and relatively high-viscosity ionic liquid, 1-n-butyl-3-methylimidazolium bis(trifluoromethane-sulfonyl)imide ([BMIM][Tf2N]), over a range of temperatures. These test cases show that the method is robust and yields reproducible and reliable shear viscosity values.
ERIC Educational Resources Information Center
Austin, Warren B.
Who wrote "The Groatsworth of Wit?" Was it Greene, as hitherto believed, or Chettle? To distinguish between the two writers' styles, and thereby determine the authorship of a 16th Century literary work of particular interest to Shakespearean scholars, computer-aided techniques were employed. The two authors' differing practices in word choice and…
Virtual Rewards for Driving Green
ERIC Educational Resources Information Center
Pritchard, Josh
2010-01-01
Carbon dioxide from automobiles is a major contributor to global climate change. In "Virtual Rewards for Driving Green," Josh Pritchard proposes a computer application that will enable fuel-efficient drivers to earn "green" dollars with which to buy digital merchandise on the Web. Can getting items that exist only in cyberspace actually change a…
Fire within the Antennae Galaxies
2004-09-07
This false-color image composite from NASA's Spitzer Space Telescope reveals hidden populations of newborn stars at the heart of the colliding "Antennae" galaxies. These two galaxies, known individually as NGC 4038 and 4039, are located around 68 million light-years away and have been merging together for about the last 800 million years. The latest Spitzer observations provide a snapshot of the tremendous burst of star formation triggered in the process of this collision, particularly at the site where the two galaxies overlap. The image is a composite of infrared data from Spitzer and visible-light data from Kitt Peak National Observatory, Tucson, Ariz. Visible light from stars in the galaxies (blue and green) is shown together with infrared light from warm dust clouds heated by newborn stars (red). The two nuclei, or centers, of the merging galaxies show up as yellow-white areas, one above the other. The brightest clouds of forming stars lie in the overlap region between and left of the nuclei. Throughout the sky, astronomers have identified many of these so-called "interacting" galaxies, whose spiral discs have been stretched and distorted by their mutual gravity as they pass close to one another. The distances involved are so large that the interactions evolve on timescales comparable to geologic changes on Earth. Observations of such galaxies, combined with computer models of these collisions, show that the galaxies often become forever bound to one another, eventually merging into a single, spheroidal-shaped galaxy. Wavelengths of 0.44 microns are represented in blue, .70 microns in green and 8.0 microns in red. This image was taken on Dec. 24, 2003. http://photojournal.jpl.nasa.gov/catalog/PIA06854
Lava and Snow on Klyuchevskaya Volcano [detail
2017-12-08
This false-color (shortwave infrared, near infrared, green) satellite image reveals an active lava flow on the western slopes of Klyuchevskaya Volcano. Klyuchevskaya is one of several active volcanoes on the Kamchatka Peninsula in far eastern Russia. The lava flow itself is bright red. Snow on Klyuchevskaya and nearby mountains is cyan, while bare ground and volcanic debris is gray or brown. Vegetation is green. The image was collected by Landsat 8 on September 9, 2013. NASA Earth Observatory image by Jesse Allen and Robert Simmon, using Instrument: Landsat 8 - OLI More info: 1.usa.gov/1evspH7 NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram
Model reduction of the numerical analysis of Low Impact Developments techniques
NASA Astrophysics Data System (ADS)
Brunetti, Giuseppe; Šimůnek, Jirka; Wöhling, Thomas; Piro, Patrizia
2017-04-01
Mechanistic models have proven to be accurate and reliable tools for the numerical analysis of the hydrological behavior of Low Impact Development (LIDs) techniques. However, their widespread adoption is limited by their complexity and computational cost. Recent studies have tried to address this issue by investigating the application of new techniques, such as surrogate-based modeling. However, current results are still limited and fragmented. One of such approaches, the Model Order Reduction (MOR) technique, can represent a valuable tool for reducing the computational complexity of a numerical problems by computing an approximation of the original model. While this technique has been extensively used in water-related problems, no studies have evaluated its use in LIDs modeling. Thus, the main aim of this study is to apply the MOR technique for the development of a reduced order model (ROM) for the numerical analysis of the hydrologic behavior of LIDs, in particular green roofs. The model should be able to correctly reproduce all the hydrological processes of a green roof while reducing the computational cost. The proposed model decouples the subsurface water dynamic of a green roof in a) one-dimensional (1D) vertical flow through a green roof itself and b) one-dimensional saturated lateral flow along the impervious rooftop. The green roof is horizontally discretized in N elements. Each element represents a vertical domain, which can have different properties or boundary conditions. The 1D Richards equation is used to simulate flow in the substrate and drainage layers. Simulated outflow from the vertical domain is used as a recharge term for saturated lateral flow, which is described using the kinematic wave approximation of the Boussinesq equation. The proposed model has been compared with the mechanistic model HYDRUS-2D, which numerically solves the Richards equation for the whole domain. The HYDRUS-1D code has been used for the description of vertical flow, while a Finite Volume Scheme has been adopted for lateral flow. Two scenarios involving flat and steep green roofs were analyzed. Results confirmed the accuracy of the reduced order model, which was able to reproduce both subsurface outflow and the moisture distribution in the green roof, significantly reducing the computational cost.
Anayama, Takashi; Hirohashi, Kentaro; Miyazaki, Ryohei; Okada, Hironobu; Kawamoto, Nobutaka; Yamamoto, Marino; Sato, Takayuki; Orihashi, Kazumasa
2018-01-12
Minimally invasive video-assisted thoracoscopic surgery for small-sized pulmonary nodules is challenging, and image-guided preoperative localisation is required. Near-infrared indocyanine green fluorescence is capable of deep tissue penetration and can be distinguished regardless of the background colour of the lung; thus, indocyanine green has great potential for use as a near-infrared fluorescent marker in video-assisted thoracoscopic surgery. Thirty-seven patients with small-sized pulmonary nodules, who were scheduled to undergo video-assisted thoracoscopic wedge resection, were enrolled in this study. A mixture of diluted indocyanine green and iopamidol was injected into the lung parenchyma as a marker, using either computed tomography-guided percutaneous or bronchoscopic injection techniques. Indications and limitations of the percutaneous and bronchoscopic injection techniques for marking nodules with indocyanine green fluorescence were examined and compared. In the computed tomography-guided percutaneous injection group (n = 15), indocyanine green fluorescence was detected in 15/15 (100%) patients by near-infrared thoracoscopy. A small pneumothorax occurred in 3/15 (20.0%) patients, and subsequent marking was unsuccessful after a pneumothorax occurred. In the bronchoscopic injection group (n = 22), indocyanine green fluorescence was detected in 21/22 (95.5%) patients. In 6 patients who underwent injection marking at 2 different lesion sites, 5/6 (83.3%) markers were successfully detected. Either computed tomography-guided percutaneous or bronchoscopic injection techniques can be used to mark pulmonary nodules with indocyanine green fluorescence. Indocyanine green is a safe and easily detectable fluorescent marker for video-assisted thoracoscopic surgery. Furthermore, the bronchoscopic injection approach enables surgeons to mark multiple lesion areas with less risk of causing a pneumothorax. UMIN-CTR R000027833 accepted by ICMJE. Registered 5 January 2013.
Telescopes in Education: the Little Thompson Observatory
NASA Astrophysics Data System (ADS)
Schweitzer, A. E.; Melsheimer, T. T.
2002-05-01
The Little Thompson Observatory is believed to be the first of its kind, located next to a high school and accessible to other schools remotely over the Internet. This observatory is the second member of the Telescopes in Education (TIE) project. Construction was done completely by volunteer labor, and the observatory was built on the grounds of Berthoud High School in northern Colorado. During 2001, we averaged 400-500 visitors per month. We are grateful to have received a STScI IDEAS grant to provide teacher training workshops for K-12 schools in northern Colorado to make use of the observatory, including remote observing from classrooms. Students connect to the observatory over the Internet, and then receive the images back on their local computers. We are honored that a committee of teachers and administrators from the Thompson School district have selected these workshops to count towards Incentive Credits (movement on the salary schedule) because the course meets the criteria: "Learning must be directly transferable to the classroom with students and relate to standards, assessment and/or technology." Also in the past year, our training materials have been shared with NASA Goddard and Howard University, which are working together to develop a similar teacher education program. Our next goal is to add solar observing capability! Please visit our website at www.starkids.org.
Observatory for education and public outreach controlled through the World Wide Web
NASA Astrophysics Data System (ADS)
Guzik, T. Gregory; Motl, Patrick M.; Burks, Geoffrey S.; Fisher, Paul; Giammanco, James; Landolt, Arlo U.; Stacy, J. G.; Tohline, Joel E.; Wefel, Katrina
1998-05-01
For the last two and a half years the Department of Physics and Astronomy at Louisiana State University has been engaged in a collaborative effort with the Recreation and Park Commission for the Parish of East Baton Rouge and the Baton Rouge Astronomical Society to develop a observatory that can be used for astronomy education from primary school; through graduate studies as well as for recreation and public outreach. The observatory includes a 2,300 square feet facility, a 20-inch diameter Ritchey-Chretien telescope, a black-thinned CCD camera, a computer control system and an internet T1 link. The on site public outreach and education program has been fully active since Fall, 1997 and we are currently in the process of developing a platform- independent system for remotely controlling the observatory over the internet. The initial version of the Java/World Wide Web based software is currently functioning and provides interactive control of the observatory via any Java compatible web browser. The main principles of the remote control system are presented in this paper, along with a discussion of the education and outreach goals of the observatory, details of the facility and hardware, initial measurements of system performance, and a discussion of our future development plans.
Radio Telescopes "Save the Day," Produce Data on Titan's Winds
NASA Astrophysics Data System (ADS)
2005-02-01
In what some scientists termed "a surprising, almost miraculous turnabout," radio telescopes, including major facilities of the National Science Foundation's National Radio Astronomy Observatory (NRAO), have provided data needed to measure the winds encountered by the Huygens spacecraft as it descended through the atmosphere of Saturn's moon Titan last month -- measurements feared lost because of a communication error between Huygens and its "mother ship" Cassini. The Green Bank Telescope The Robert C. Byrd Green Bank Telescope CREDIT: NRAO/AUI/NSF (Click on image for GBT gallery) A global network of radio telescopes, including the NRAO's Robert C. Byrd Green Bank Telescope (GBT) in West Virginia and eight of the ten antennas of the Very Long Baseline Array (VLBA), recorded the radio signal from Huygens during its descent on January 14. Measurements of the frequency shift caused by the craft's motion, called Doppler shift, are giving planetary scientists their first direct information about Titan's winds. "When we began working with our international partners on this project, we thought our telescopes would be adding to the wind data produced by the two spacecraft themselves. Now, with the ground-based telescopes providing the only information about Titan's winds, we are extremely proud that our facilities are making such a key contribution to our understanding of this fascinating planetary body," said Dr. Fred K.Y. Lo, Director of the National Radio Astronomy Observatory (NRAO). Early analysis of the radio-telescope data shows that Titan's wind flows from west to east, in the direction of the moon's rotation, at all altitudes. The highest wind speed, nearly 270 mph, was measured at an altitude of about 75 miles. Winds are weak near Titan's surface and increase in speed slowly up to an altitude of about 37 miles, where the spacecraft encountered highly-variable winds that scientists think indicate a region of vertical wind shear. The ground-based Doppler measurements were carried out and processed jointly by scientists from the NASA Jet Propulsion Laboratory (JPL, USA), and the Joint Institute for VLBI in Europe (JIVE, The Netherlands) working within an international Doppler Wind Experiment team. The GBT made the first detection of Huygens' radio signal during the descent, and gave flight controllers and scientists the first indication that the spacecraft's parachute had deployed and that it was "alive" after entering Titan's atmosphere. The radio-telescope measurements also indicated changes in Huygens' speed when it exchanged parachutes and when it landed on Titan's surface. The original plan for gauging Titan's winds called for measuring the Doppler shift in the probe's signal frequency both by Cassini and by ground-based radio telescopes in the U.S., Australia, Japan and China. Cassini was best positioned to gain information on the east-west component of the winds, and the ground-based telescopes were positioned to help learn about the north-south wind component. Unfortunately, the communications error lost all the wind data from Cassini. The VLBA The VLBA CREDIT: NRAO/AUI/NSF (Click on image for VLBA gallery) "I've never felt such exhilarating highs and dispiriting lows than those experienced when we first detected the signal from the GBT, indicating 'all's well,' and then discovering that we had no signal at the operations center, indicating 'all's lost.' The truth, as we have now determined, lies somewhat closer to the former than the latter." said Michael Bird of the University of Bonn. In addition to measuring the motion-generated frequency shift of Huygens' radio signal, radio telescopes also were used to make extremely precise measurements of the probe's position (to within three-quarters of a mile, or one kilometer) during its descent. This experiment used the VLBA antennas, along with others employing the technique of Very Long Baseline Interferometry (VLBI). Combination of the Doppler and VLBI data will eventually provide a three-dimensional record of motion for the Huygens Probe during its mission at Titan. Huygens was built by the European Space Agency. The radio astronomy support of the Huygens mission is coordinated by JIVE and JPL and involves the National Radio Astronomy Observatory (Green Bank, WV and Socorro, NM), the Netherlands Foundation for Research in Astronomy (ASTRON, The Netherlands), the University of Bonn (Germany), Helsinki University of Technology (Espoo, Finland), the MERLIN National Facility (Jodrell Bank, UK), the Onsala Space Observatory (Sweden), the NASA Jet Propulsion Laboratory (Pasadena, CA), the CSIRO Australia Telescope National Facility (ATNF, Sydney, Australia), the University of Tasmania (Hobart, Australia), the National Astronomical Observatories of China, the Shanghai Astronomical Observatory (Shanghai and Urumqi, China) and the National Institute of Information and Communications Technologies (Kashima Space Research Center, Japan). The Joint Institute for VLBI in Europe is hosted by ASTRON and funded by the national research councils, national facilities and institutes of The Netherlands (NOW), the United Kingdom (PPARC), Italy (CNR), Sweden (Onsala Space Observatory, National Facility), Spain (IGN) and Germany (MPIfR). The Australia Telescope is funded by the Commonwealth of Australia for operation as a National Facility managed by CSIRO. The Cassini-Huygens mission is a cooperation between NASA, ESA and ASI, the Italian space agency. The Jet Propulsion Laboratory (JPL), a division of the California Institute of Technology in Pasadena, is managing the mission for NASA's Office of Space Science, Washington DC. JPL designed, developed and assembled the Cassini orbiter while ESA operated the Huygens atmospheric probe. The National Radio Astronomy Observatory is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc.
Virtual Observatory and Colitec Software: Modules, Features, Methods
NASA Astrophysics Data System (ADS)
Pohorelov, A. V.; Khlamov, S. V.; Savanevych, V. E.; Briukhovetskyi, A. B.; Vlasenko, V. P.
In this article we described complex processing system created by the CoLiTec project. This system includes features, user-friendly tools for processing control, results reviewing, integration with online catalogs and a lot of different computational modules that are based on the developed methods. Some of them are described in the article.The main directions of the CoLiTec software development are the Virtual Observatory, software for automated asteroids and comets detection and software for brightness equalization.The CoLiTec software is widely used in a number of observatories in the CIS. It has been used in about 700 000 observations, during which 1560 asteroids, including 5 NEO, 21 Trojan asteroids of Jupiter, 1 Centaur and four comets were discovered.
Protection of Hawaii's Observatories from Light Pollution
NASA Astrophysics Data System (ADS)
Wainscoat, Richard J.
2018-01-01
Maunakea Observatory, located on the island of Hawaii, is among the world darkest sites for astronomy. Strong efforts to preserve the dark night sky over the last forty years have proven successful. Artificial light presently adds only approximately 2% to the natural night sky brightness. The techniques being used to protect Maunakea from light pollution will be described, along with the challenges that are now being faced.Haleakala Observatory, located on the island of Maui, is also an excellent observing site, and is among the best sites in the United States. Lighting restrictions in Maui County are much weaker, and consequently, the night sky above Haleakala is less well protected. Haleakala is closer to Honolulu and the island of Oahu (population approximately 1 million), and the glow from Oahu makes the northwestern sky brighter.Much of the lighting across most of the United States, including Hawaii, is presently being converted to LED lighting. This provides an opportunity to replace existing poorly shielded lights with properly shielded LED fixtures, but careful spectral management is essential. It is critically important to only use LED lighting that is deficient in blue and green light. LED lighting also is easy to dim. Dimming of lights later at night, when there is no need for brighter lighting, is an important tool for reducing light pollution.Techniques used to protect astronomical observatories from light pollution are similar to the techniques that must be used to protect animals that are affected by light at night, such as endangered birds and turtles. These same techniques are compatible with recent human health related lighting recommendations from the American Medical Association.
Observatories Combine to Crack Open the Crab Nebula
2017-12-08
Astronomers have produced a highly detailed image of the Crab Nebula, by combining data from telescopes spanning nearly the entire breadth of the electromagnetic spectrum, from radio waves seen by the Karl G. Jansky Very Large Array (VLA) to the powerful X-ray glow as seen by the orbiting Chandra X-ray Observatory. And, in between that range of wavelengths, the Hubble Space Telescope's crisp visible-light view, and the infrared perspective of the Spitzer Space Telescope. This video starts with a composite image of the Crab Nebula, a supernova remnant that was assembled by combining data from five telescopes spanning nearly the entire breadth of the electromagnetic spectrum: the Very Large Array, the Spitzer Space Telescope, the Hubble Space Telescope, the XMM-Newton Observatory, and the Chandra X-ray Observatory. The video dissolves to the red-colored radio-light view that shows how a neutron star’s fierce “wind” of charged particles from the central neutron star energized the nebula, causing it to emit the radio waves. The yellow-colored infrared image includes the glow of dust particles absorbing ultraviolet and visible light. The green-colored Hubble visible-light image offers a very sharp view of hot filamentary structures that permeate this nebula. The blue-colored ultraviolet image and the purple-colored X-ray image shows the effect of an energetic cloud of electrons driven by a rapidly rotating neutron star at the center of the nebula. Read more: go.nasa.gov/2r0s8VC Credits: NASA, ESA, J. DePasquale (STScI)
Hamiltonian lattice field theory: Computer calculations using variational methods
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zako, Robert L.
1991-12-03
I develop a variational method for systematic numerical computation of physical quantities -- bound state energies and scattering amplitudes -- in quantum field theory. An infinite-volume, continuum theory is approximated by a theory on a finite spatial lattice, which is amenable to numerical computation. I present an algorithm for computing approximate energy eigenvalues and eigenstates in the lattice theory and for bounding the resulting errors. I also show how to select basis states and choose variational parameters in order to minimize errors. The algorithm is based on the Rayleigh-Ritz principle and Kato`s generalizations of Temple`s formula. The algorithm could bemore » adapted to systems such as atoms and molecules. I show how to compute Green`s functions from energy eigenvalues and eigenstates in the lattice theory, and relate these to physical (renormalized) coupling constants, bound state energies and Green`s functions. Thus one can compute approximate physical quantities in a lattice theory that approximates a quantum field theory with specified physical coupling constants. I discuss the errors in both approximations. In principle, the errors can be made arbitrarily small by increasing the size of the lattice, decreasing the lattice spacing and computing sufficiently long. Unfortunately, I do not understand the infinite-volume and continuum limits well enough to quantify errors due to the lattice approximation. Thus the method is currently incomplete. I apply the method to real scalar field theories using a Fock basis of free particle states. All needed quantities can be calculated efficiently with this basis. The generalization to more complicated theories is straightforward. I describe a computer implementation of the method and present numerical results for simple quantum mechanical systems.« less
Distributed Computing for the Pierre Auger Observatory
NASA Astrophysics Data System (ADS)
Chudoba, J.
2015-12-01
Pierre Auger Observatory operates the largest system of detectors for ultra-high energy cosmic ray measurements. Comparison of theoretical models of interactions with recorded data requires thousands of computing cores for Monte Carlo simulations. Since 2007 distributed resources connected via EGI grid are successfully used. The first and the second versions of production system based on bash scripts and MySQL database were able to submit jobs to all reliable sites supporting Virtual Organization auger. For many years VO auger belongs to top ten of EGI users based on the total used computing time. Migration of the production system to DIRAC interware started in 2014. Pilot jobs improve efficiency of computing jobs and eliminate problems with small and less reliable sites used for the bulk production. The new system has also possibility to use available resources in clouds. Dirac File Catalog replaced LFC for new files, which are organized in datasets defined via metadata. CVMFS is used for software distribution since 2014. In the presentation we give a comparison of the old and the new production system and report the experience on migrating to the new system.
Lights, Camera, Spectroscope! The Basics of Spectroscopy Disclosed Using a Computer Screen
ERIC Educational Resources Information Center
Garrido-Gonza´lez, Jose´ J.; Trillo-Alcala´, María; Sa´nchez-Arroyo, Antonio J.
2018-01-01
The generation of secondary colors in digital devices by means of the additive red, green, and blue color model (RGB) can be a valuable way to introduce students to the basics of spectroscopy. This work has been focused on the spectral separation of secondary colors of light emitted by a computer screen into red, green, and blue bands, and how the…
The time light signals of New Zealand: yet another way of communicating time in the pre-wireless era
NASA Astrophysics Data System (ADS)
Kinns, Roger
2017-08-01
The signalling of exact time using an array of lights appears to have been unique to New Zealand. It was a simple and effective solution for calibration of marine chronometers when transmission of time signals by wireless was in its infancy. Three lights, coloured green, red and white, were arranged in a vertical array. They were switched on in a defined sequence during the evening and then extinguished together to signal exact time. Time lights were first operated at the Dominion Observatory in Wellington during February 1912 and on the Ferry Building in Auckland during October 1915. The Wellington lights were immediately adjacent to the observatory buildings, but those in Auckland were operated using telegraph signals from Wellington. The timings varied over the years, but the same physical arrangement was retained at each location. The time light service was withdrawn during 1937, when wireless signals had become almost universally available for civil and navigation purposes.
Model shape and spin direction of the asteroid 2011 UW158
NASA Astrophysics Data System (ADS)
Silva, José; Monteiro, Filipe; Tamayo, Francisco
2017-10-01
We determinate the spin direction and convex model shape of the Near Earth Asteroid 2011 UW158 using the lightcurves from the Minor Planet Center database and obtained from the San Pedro Mártir observatory (Ensenada, Baja California, Mexico) and the Observatório Astronômico do Sertão de Itaparica (Itacuruba, Pernambuco, Brazil) by mean of the light-curve inversion technique.The shape model was compared with the radar images obtained from the 230-foot-wide Deep Space Network antenna at Goldstone, California, in concert with the National Radio Astronomy Observatory's 330-foot Green Bank Telescope in July 2015 and with the spin direction published for Carbognani et. al (2016).We found that the spin direction given for Carbognani et al. does not correspond with the visual geometry observed from the radar images. Also, we try to minimize the number of lightcurves that reproduce the shape in a robust way, with the objective of to plan future observations of asteroids better and prioritize time.
Dong, Chun-wang; Zhu, Hong-kai; Zhao, Jie-wen; Jiang, Yong-wen; Yuan, Hai-bo; Chen, Quan-sheng
2017-01-01
Tea is one of the three greatest beverages in the world. In China, green tea has the largest consumption, and needle-shaped green tea, such as Maofeng tea and Sparrow Tongue tea, accounts for more than 40% of green tea (Zhu et al., 2017). The appearance of green tea is one of the important indexes during the evaluation of green tea quality. Especially in market transactions, the price of tea is usually determined by its appearance (Zhou et al., 2012). Human sensory evaluation is usually conducted by experts, and is also easily affected by various factors such as light, experience, psychological and visual factors. In the meantime, people may distinguish the slight differences between similar colors or textures, but the specific levels of the tea are hard to determine (Chen et al., 2008). As human description of color and texture is qualitative, it is hard to evaluate the sensory quality accurately, in a standard manner, and objectively. Color is an important visual property of a computer image (Xie et al., 2014; Khulal et al., 2016); texture is a visual performance of image grayscale and color changing with spatial positions, which can be used to describe the roughness and directivity of the surface of an object (Sanaeifar et al., 2016). There are already researchers who have used computer visual image technologies to identify the varieties, levels, and origins of tea (Chen et al., 2008; Xie et al., 2014; Zhu et al., 2017). Most of their research targets are crush, tear, and curl (CTC) red (green) broken tea, curly green tea (Bilochun tea), and flat-typed green tea (West Lake Dragon-well green tea) as the information sources. However, the target of the above research is to establish a qualitative evaluation method on tea quality (Fu et al., 2013). There is little literature on the sensory evaluation of the appearance quality of needle-shaped green tea, especially research on a quantitative evaluation model (Zhou et al., 2012; Zhu et al., 2017). PMID:28585431
Dong, Chun-Wang; Zhu, Hong-Kai; Zhao, Jie-Wen; Jiang, Yong-Wen; Yuan, Hai-Bo; Chen, Quan-Sheng
2017-06-01
Tea is one of the three greatest beverages in the world. In China, green tea has the largest consumption, and needle-shaped green tea, such as Maofeng tea and Sparrow Tongue tea, accounts for more than 40% of green tea (Zhu et al., 2017). The appearance of green tea is one of the important indexes during the evaluation of green tea quality. Especially in market transactions, the price of tea is usually determined by its appearance (Zhou et al., 2012). Human sensory evaluation is usually conducted by experts, and is also easily affected by various factors such as light, experience, psychological and visual factors. In the meantime, people may distinguish the slight differences between similar colors or textures, but the specific levels of the tea are hard to determine (Chen et al., 2008). As human description of color and texture is qualitative, it is hard to evaluate the sensory quality accurately, in a standard manner, and objectively. Color is an important visual property of a computer image (Xie et al., 2014; Khulal et al., 2016); texture is a visual performance of image grayscale and color changing with spatial positions, which can be used to describe the roughness and directivity of the surface of an object (Sanaeifar et al., 2016). There are already researchers who have used computer visual image technologies to identify the varieties, levels, and origins of tea (Chen et al., 2008; Xie et al., 2014; Zhu et al., 2017). Most of their research targets are crush, tear, and curl (CTC) red (green) broken tea, curly green tea (Bilochun tea), and flat-typed green tea (West Lake Dragon-well green tea) as the information sources. However, the target of the above research is to establish a qualitative evaluation method on tea quality (Fu et al., 2013). There is little literature on the sensory evaluation of the appearance quality of needle-shaped green tea, especially research on a quantitative evaluation model (Zhou et al., 2012; Zhu et al., 2017).
The National Virtual Observatory
NASA Astrophysics Data System (ADS)
Hanisch, Robert J.
2001-06-01
The National Virtual Observatory is a distributed computational facility that will provide access to the ``virtual sky''-the federation of astronomical data archives, object catalogs, and associated information services. The NVO's ``virtual telescope'' is a common framework for requesting, retrieving, and manipulating information from diverse, distributed resources. The NVO will make it possible to seamlessly integrate data from the new all-sky surveys, enabling cross-correlations between multi-Terabyte catalogs and providing transparent access to the underlying image or spectral data. Success requires high performance computational systems, high bandwidth network services, agreed upon standards for the exchange of metadata, and collaboration among astronomers, astronomical data and information service providers, information technology specialists, funding agencies, and industry. International cooperation at the onset will help to assure that the NVO simultaneously becomes a global facility. .
NASA Astrophysics Data System (ADS)
Chibani, Wael; Ren, Xinguo; Scheffler, Matthias; Rinke, Patrick
2016-04-01
We present an embedding scheme for periodic systems that facilitates the treatment of the physically important part (here a unit cell or a supercell) with advanced electronic structure methods, that are computationally too expensive for periodic systems. The rest of the periodic system is treated with computationally less demanding approaches, e.g., Kohn-Sham density-functional theory, in a self-consistent manner. Our scheme is based on the concept of dynamical mean-field theory formulated in terms of Green's functions. Our real-space dynamical mean-field embedding scheme features two nested Dyson equations, one for the embedded cluster and another for the periodic surrounding. The total energy is computed from the resulting Green's functions. The performance of our scheme is demonstrated by treating the embedded region with hybrid functionals and many-body perturbation theory in the GW approach for simple bulk systems. The total energy and the density of states converge rapidly with respect to the computational parameters and approach their bulk limit with increasing cluster (i.e., computational supercell) size.
NASA Astrophysics Data System (ADS)
Cassan, Arnaud
2017-07-01
The exoplanet detection rate from gravitational microlensing has grown significantly in recent years thanks to a great enhancement of resources and improved observational strategy. Current observatories include ground-based wide-field and/or robotic world-wide networks of telescopes, as well as space-based observatories such as satellites Spitzer or Kepler/K2. This results in a large quantity of data to be processed and analysed, which is a challenge for modelling codes because of the complexity of the parameter space to be explored and the intensive computations required to evaluate the models. In this work, I present a method that allows to compute the quadrupole and hexadecapole approximations of the finite-source magnification with more efficiency than previously available codes, with routines about six times and four times faster, respectively. The quadrupole takes just about twice the time of a point-source evaluation, which advocates for generalizing its use to large portions of the light curves. The corresponding routines are available as open-source python codes.
The Role of the Virtual Astronomical Observatory in the Era of Big Data
NASA Astrophysics Data System (ADS)
Berriman, G. B.; Hanisch, R. J.; Lazio, T. J.
2013-01-01
The Virtual Observatory (VO) is realizing global electronic integration of astronomy data. The rapid growth in the size and complexity of data sets is transforming the computing landscape in astronomy. One of the long-term goals of the U.S. VO project, the Virtual Astronomical Observatory (VAO), is development of an information backbone that responds to this growth. Such a backbone will, when complete, provide innovative mechanisms for fast discovery of, and access to, massive data sets, and services that enable distributed storage, publication processing of large datasets. All these services will be built so that new projects can incorporate them as part of their data management and processing plans. Services under development to date include a general purpose indexing scheme for fast access to data sets, a cross-comparison engine that operate on catalogs of 1 billion records or more, and an interface for managing distributed data sets and connecting them to data discovery and analysis tools. The VAO advises projects on technology solutions for their data access and processing needs, and recently advised the Sagan Workshop on using cloud computing to support hands-on data analysis sessions for 150+ participants. Acknowledgements: The Virtual Astronomical Observatory (VAO) is managed by the VAO, LLC, a non-profit company established as a partnership of the Associated Universities, Inc. and the Association of Universities for Research in Astronomy, Inc. The VAO is sponsored by the National Science Foundation and the National Aeronautics and Space Administration.
NASA Astrophysics Data System (ADS)
Farid, V. L.; Wonorahardjo, S.
2018-05-01
The implementation of Green Building criteria is relatively new in architectural practice, especially in Indonesia. Consequently, the integration of these criteria into design process has the potential to change the design process itself. The implementation of the green building criteria into the conventional design process will be discussed in this paper. The concept of this project is to design a residential unit with a natural air-conditioning system. To achieve this purpose, the Green Building criteria has been implemented since the beginning of the design process until the detailing process on the end of the project. Several studies was performed throughout the design process, such as: (1) Conceptual review, where several professionally proved theories related to Tropical Architecture and passive design are used for a reference, and (2) Computer simulations, such as Computational Fluid Dynamics (CFD) and wind tunnel simulation, used to represent the dynamic response of the surrounding environment towards the building. Hopefully this paper may become a reference for designing a green residential building.
Estimating the weight of Douglas-fir tree boles and logs with an iterative computer model.
Dale R. Waddell; Dale L Weyermann; Michael B. Lambert
1987-01-01
A computer model that estimates the green weights of standing trees was developed and validated for old-growth Douglas-fir. The model calculates the green weight for the entire bole, for the bole to any merchantable top, and for any log length within the bole. The model was validated by estimating the bias and accuracy of an independent subsample selected from the...
Local area networking in a radio quiet environment
NASA Astrophysics Data System (ADS)
Childers, Edwin L.; Hunt, Gareth; Brandt, Joseph J.
2002-11-01
The Green Bank facility of the National Radio Astronomy Observatory is spread out over 2,700 acres in the Allegheny Mountains of West Virginia. Good communication has always been needed between the radio telescopes and the control buildings. The National Radio Quiet Zone helps protect the Green Bank site from radio transmissions that interfere with the astronomical signals. Due to stringent Radio Frequency Interference (RFI) requirements, a fiber optic communication system was used for Ethernet transmissions on the site and coaxial cable within the buildings. With the need for higher speed communications, the entire network has been upgraded to use optical fiber with modern Ethernet switches. As with most modern equipment, the implementation of the control of the newly deployed Green Bank Telescope (GBT) depends heavily on TCP/IP. In order to protect the GBT from the commodity Internet, the GBT uses a non-routable network. Communication between the control building Local Area Network (LAN) and the GBT is implemented using a Virtual LAN (VLAN). This configuration will be extended to achieve isolation between trusted local user systems, the GBT, and other Internet users. Legitimate access to the site, for example by remote observers, is likely to be implemented using a virtual private network (VPN).
Computational fluid dynamic modeling of the summit of Mt. Hopkins for the MMT Observatory
NASA Astrophysics Data System (ADS)
Callahan, S.
2010-07-01
Over the past three decades, the staff of the MMT observatory used a variety of techniques to predict the summit wind characteristics including wind tunnel modeling and the release of smoke bombs. With the planned addition of a new instrument repair facility to be constructed on the summit of Mt. Hopkins, new computational fluid dynamic (CFD) models were made to determine the building's influence on the thermal environment around the telescope. The models compared the wind profiles and density contours above the telescope enclosure with and without the new building. The results show the steeply-sided Mount Hopkins dominates the summit wind profiles. In typical winds, the height of the telescope remains above the ground layer and is sufficiently separated from the new facility to insure the heat from the new building does not interfere with the telescope. The results also confirmed the observatories waste heat exhaust duct location needs to be relocated to prevent heat from being trapped in the wind shadow of the new building and lofting above the telescope. These useful models provide many insights into understanding the thermal environment of the summit.
NASA Astrophysics Data System (ADS)
Brecher, K.; Sadler, P.
1994-12-01
A group of scientists, engineers and educators based at the Harvard-Smithsonian Center for Astrophysics (CfA) has developed a prototype of a small, inexpensive and fully integrated automated astronomical telescope and image processing system. The project team is now building five second generation instruments. The MicroObservatory has been designed to be used for classroom instruction by teachers as well as for original scientific research projects by students. Probably in no other area of frontier science is it possible for a broad spectrum of students (not just the gifted) to have access to state-of-the-art technologies that would allow for original research. The MicroObservatory combines the imaging power of a cooled CCD, with a self contained and weatherized reflecting optical telescope and mount. A microcomputer points the telescope and processes the captured images. The MicroObservatory has also been designed to be used as a valuable new capture and display device for real time astronomical imaging in planetariums and science museums. When the new instruments are completed in the next few months, they will be tried with high school students and teachers, as well as with museum groups. We are now planning to make the MicroObservatories available to students, teachers and other individual users over the Internet. We plan to allow the telescope to be controlled in real time or in batch mode, from a Macintosh or PC compatible computer. In the real-time mode, we hope to give individual access to all of the telescope control functions without the need for an "on-site" operator. Users would sign up for a specific period of time. In the batch mode, users would submit jobs for the telescope. After the MicroObservatory completed a specific job, the images would be e-mailed back to the user. At present, we are interested in gaining answers to the following questions: (1) What are the best approaches to scheduling real-time observations? (2) What criteria should be used for granting telescope time? (3) What are the best approaches to scheduling batch-mode operation? (4) With deployment of more than one telescope, is it advantageous for each telescope to be used for just one type of observation, i.e., some for photometric use, others for imaging? The MicroObservatory is supported in part by grants from the NSF, Apple Computers and Eastman Kodak.
Investigation of a Sybr-Green-Based Method to Validate DNA Sequences for DNA Computing
2005-05-01
OF A SYBR-GREEN-BASED METHOD TO VALIDATE DNA SEQUENCES FOR DNA COMPUTING 6. AUTHOR(S) Wendy Pogozelski, Salvatore Priore, Matthew Bernard ...simulated annealing. Biochemistry, 35, 14077-14089. 15 Pogozelski, W.K., Bernard , M.P. and Macula, A. (2004) DNA code validation using...and Clark, B.F.C. (eds) In RNA Biochemistry and Biotechnology, NATO ASI Series, Kluwer Academic Publishers. Zucker, M. and Stiegler , P. (1981
Danel, J-F; Kazandjian, L; Zérah, G
2012-06-01
Computations of the self-diffusion coefficient and viscosity in warm dense matter are presented with an emphasis on obtaining numerical convergence and a careful evaluation of the standard deviation. The transport coefficients are computed with the Green-Kubo relation and orbital-free molecular dynamics at the Thomas-Fermi-Dirac level. The numerical parameters are varied until the Green-Kubo integral is equal to a constant in the t→+∞ limit; the transport coefficients are deduced from this constant and not by extrapolation of the Green-Kubo integral. The latter method, which gives rise to an unknown error, is tested for the computation of viscosity; it appears that it should be used with caution. In the large domain of coupling constant considered, both the self-diffusion coefficient and viscosity turn out to be well approximated by simple analytical laws using a single effective atomic number calculated in the average-atom model.
NASA Astrophysics Data System (ADS)
Danel, J.-F.; Kazandjian, L.; Zérah, G.
2012-06-01
Computations of the self-diffusion coefficient and viscosity in warm dense matter are presented with an emphasis on obtaining numerical convergence and a careful evaluation of the standard deviation. The transport coefficients are computed with the Green-Kubo relation and orbital-free molecular dynamics at the Thomas-Fermi-Dirac level. The numerical parameters are varied until the Green-Kubo integral is equal to a constant in the t→+∞ limit; the transport coefficients are deduced from this constant and not by extrapolation of the Green-Kubo integral. The latter method, which gives rise to an unknown error, is tested for the computation of viscosity; it appears that it should be used with caution. In the large domain of coupling constant considered, both the self-diffusion coefficient and viscosity turn out to be well approximated by simple analytical laws using a single effective atomic number calculated in the average-atom model.
An observatory control system for the University of Hawai'i 2.2m Telescope
NASA Astrophysics Data System (ADS)
McKay, Luke; Erickson, Christopher; Mukensnable, Donn; Stearman, Anthony; Straight, Brad
2016-07-01
The University of Hawai'i 2.2m telescope at Maunakea has operated since 1970, and has had several controls upgrades to date. The newest system will operate as a distributed hierarchy of GNU/Linux central server, networked single-board computers, microcontrollers, and a modular motion control processor for the main axes. Rather than just a telescope control system, this new effort is towards a cohesive, modular, and robust whole observatory control system, with design goals of fully robotic unattended operation, high reliability, and ease of maintenance and upgrade.
Methods for Cloud Cover Estimation
NASA Technical Reports Server (NTRS)
Glackin, D. L.; Huning, J. R.; Smith, J. H.; Logan, T. L.
1984-01-01
Several methods for cloud cover estimation are described relevant to assessing the performance of a ground-based network of solar observatories. The methods rely on ground and satellite data sources and provide meteorological or climatological information. One means of acquiring long-term observations of solar oscillations is the establishment of a ground-based network of solar observatories. Criteria for station site selection are: gross cloudiness, accurate transparency information, and seeing. Alternative methods for computing this duty cycle are discussed. The cycle, or alternatively a time history of solar visibility from the network, can then be input to a model to determine the effect of duty cycle on derived solar seismology parameters. Cloudiness from space is studied to examine various means by which the duty cycle might be computed. Cloudiness, and to some extent transparency, can potentially be estimated from satellite data.
Reduced-order surrogate models for Green's functions in black hole spacetimes
NASA Astrophysics Data System (ADS)
Galley, Chad; Wardell, Barry
2016-03-01
The fundamental nature of linear wave propagation in curved spacetime is encoded in the retarded Green's function (or propagator). Green's functions are useful tools because almost any field quantity of interest can be computed via convolution integrals with a source. In addition, perturbation theories involving nonlinear wave propagation can be expressed in terms of multiple convolutions of the Green's function. Recently, numerical solutions for propagators in black hole spacetimes have been found that are globally valid and accurate for computing physical quantities. However, the data generated is too large for practical use because the propagator depends on two spacetime points that must be sampled finely to yield accurate convolutions. I describe how to build a reduced-order model that can be evaluated as a substitute, or surrogate, for solutions of the curved spacetime Green's function equation. The resulting surrogate accurately and quickly models the original and out-of-sample data. I discuss applications of the surrogate, including self-consistent evolutions and waveforms of extreme mass ratio binaries. Green's function surrogate models provide a new and practical way to handle many old problems involving wave propagation and motion in curved spacetimes.
Green Supercomputing at Argonne
Pete Beckman
2017-12-09
Pete Beckman, head of Argonne's Leadership Computing Facility (ALCF) talks about Argonne National Laboratory's green supercomputingâeverything from designing algorithms to use fewer kilowatts per operation to using cold Chicago winter air to cool the machine more efficiently.
There's a Green Glob in Your Classroom.
ERIC Educational Resources Information Center
Dugdale, Sharon
1983-01-01
Discusses computer games (called intrinsic models) focusing on mathematics rather than on unrelated motivations (flashing lights or sounds). Games include "Green Globs," (equations/linear functions), "Darts"/"Torpedo" (fractions), "Escape" (graphing), and "Make-a-Monster" (equivalent fractions and…
Determination and uncertainty of moment tensors for microearthquakes at Okmok Volcano, Alaska
Pesicek, J.D.; Sileny, J.; Prejean, S.G.; Thurber, C.H.
2012-01-01
Efforts to determine general moment tensors (MTs) for microearthquakes in volcanic areas are often hampered by small seismic networks, which can lead to poorly constrained hypocentres and inadequate modelling of seismic velocity heterogeneity. In addition, noisy seismic signals can make it difficult to identify phase arrivals correctly for small magnitude events. However, small volcanic earthquakes can have source mechanisms that deviate from brittle double-couple shear failure due to magmatic and/or hydrothermal processes. Thus, determining reliable MTs in such conditions is a challenging but potentially rewarding pursuit. We pursued such a goal at Okmok Volcano, Alaska, which erupted recently in 1997 and in 2008. The Alaska Volcano Observatory operates a seismic network of 12 stations at Okmok and routinely catalogues recorded seismicity. Using these data, we have determined general MTs for seven microearthquakes recorded between 2004 and 2007 by inverting peak amplitude measurements of P and S phases. We computed Green's functions using precisely relocated hypocentres and a 3-D velocity model. We thoroughly assessed the quality of the solutions by computing formal uncertainty estimates, conducting a variety of synthetic and sensitivity tests, and by comparing the MTs to solutions obtained using alternative methods. The results show that MTs are sensitive to station distribution and errors in the data, velocity model and hypocentral parameters. Although each of the seven MTs contains a significant non-shear component, we judge several of the solutions to be unreliable. However, several reliable MTs are obtained for a group of previously identified repeating events, and are interpreted as compensated linear-vector dipole events.
The Breakthrough Listen Initiative and the Future of the Search for Intelligent Life
NASA Astrophysics Data System (ADS)
Enriquez, J. Emilio; Siemion, Andrew; Croft, Steve; Hellbourg, Greg; Lebofsky, Matt; MacMahon, David; Price, Danny; DeBoer, David; Werthimer, Dan
2017-05-01
Unprecedented recent results in the fields of exoplanets and astrobiology have dramatically increased the interest in the potential existence of intelligent life elsewhere in the galaxy. Additionally, the capabilities of modern Searches for Extraterrestrial Intelligence (SETI) have increased tremendously. Much of this improvement is due to the ongoing development of wide bandwidth radio instruments and the Moore's Law increase in computing power over the previous decades. Together, these instrumentation improvements allow for narrow band signal searches of billions of frequency channels at once.The Breakthrough Listen Initiative (BL) was launched on July 20, 2015 at the Royal Society in London, UK with the goal to conduct the most comprehensive and sensitive search for advanced life in humanity's history. Here we detail important milestones achieved during the first year and a half of the program. We describe the key BL SETI surveys and briefly describe current facilities, including the Green Bank Telescope, the Automated Planet Finder and the Parkes Observatory. We also mention the ongoing and potential collaborations focused on complementary sciences, these include pulse searches of pulsars and FRBs, as well as astrophysically powered radio emission from stars targeted by our program.We conclude with a brief view towards future SETI searches with upcoming next-generation radio facilities such as SKA and ngVLA.
The Five-hundred-meter Aperture Spherical Radio Telescope Project
NASA Astrophysics Data System (ADS)
Li, Di; Pan, Zhichen
2016-07-01
The Five-hundred-meter Aperture Spherical Radio Telescope (FAST) is a Chinese megascience project funded by the National Development and Reform Commission (NDRC) of the People's Republic of China. The National Astronomical Observatories of China (NAOC) is in charge of its construction and subsequent operation. Upon its expected completion in September 2016, FAST will surpass the 305 m Arecibo Telescope and the 100 m Green Bank Telescope in terms of absolute sensitivity in the 70 MHz to 3 GHz bands. In this paper, we report on the project, its current status, the key science goals, and plans for early science.
Computing the Dynamic Response of a Stratified Elastic Half Space Using Diffuse Field Theory
NASA Astrophysics Data System (ADS)
Sanchez-Sesma, F. J.; Perton, M.; Molina Villegas, J. C.
2015-12-01
The analytical solution for the dynamic response of an elastic half-space for a normal point load at the free surface is due to Lamb (1904). For a tangential force, we have Chaós (1960) formulae. For an arbitrary load at any depth within a stratified elastic half space, the resulting elastic field can be given in the same fashion, by using an integral representation in the radial wavenumber domain. Typically, computations use discrete wave number (DWN) formalism and Fourier analysis allows for solution in space and time domain. Experimentally, these elastic Greeńs functions might be retrieved from ambient vibrations correlations when assuming a diffuse field. In fact, the field could not be totally diffuse and only parts of the Green's functions, associated to surface or body waves, are retrieved. In this communication, we explore the computation of Green functions for a layered media on top of a half-space using a set of equipartitioned elastic plane waves. Our formalism includes body and surface waves (Rayleigh and Love waves). These latter waves correspond to the classical representations in terms of normal modes in the asymptotic case of large separation distance between source and receiver. This approach allows computing Green's functions faster than DWN and separating the surface and body wave contributions in order to better represent Green's function experimentally retrieved.
Verification and Validation: High Charge and Energy (HZE) Transport Codes and Future Development
NASA Technical Reports Server (NTRS)
Wilson, John W.; Tripathi, Ram K.; Mertens, Christopher J.; Blattnig, Steve R.; Clowdsley, Martha S.; Cucinotta, Francis A.; Tweed, John; Heinbockel, John H.; Walker, Steven A.; Nealy, John E.
2005-01-01
In the present paper, we give the formalism for further developing a fully three-dimensional HZETRN code using marching procedures but also development of a new Green's function code is discussed. The final Green's function code is capable of not only validation in the space environment but also in ground based laboratories with directed beams of ions of specific energy and characterized with detailed diagnostic particle spectrometer devices. Special emphasis is given to verification of the computational procedures and validation of the resultant computational model using laboratory and spaceflight measurements. Due to historical requirements, two parallel development paths for computational model implementation using marching procedures and Green s function techniques are followed. A new version of the HZETRN code capable of simulating HZE ions with either laboratory or space boundary conditions is under development. Validation of computational models at this time is particularly important for President Bush s Initiative to develop infrastructure for human exploration with first target demonstration of the Crew Exploration Vehicle (CEV) in low Earth orbit in 2008.
Computer Vision for the Solar Dynamics Observatory (SDO)
NASA Astrophysics Data System (ADS)
Martens, P. C. H.; Attrill, G. D. R.; Davey, A. R.; Engell, A.; Farid, S.; Grigis, P. C.; Kasper, J.; Korreck, K.; Saar, S. H.; Savcheva, A.; Su, Y.; Testa, P.; Wills-Davey, M.; Bernasconi, P. N.; Raouafi, N.-E.; Delouille, V. A.; Hochedez, J. F.; Cirtain, J. W.; Deforest, C. E.; Angryk, R. A.; de Moortel, I.; Wiegelmann, T.; Georgoulis, M. K.; McAteer, R. T. J.; Timmons, R. P.
2012-01-01
In Fall 2008 NASA selected a large international consortium to produce a comprehensive automated feature-recognition system for the Solar Dynamics Observatory (SDO). The SDO data that we consider are all of the Atmospheric Imaging Assembly (AIA) images plus surface magnetic-field images from the Helioseismic and Magnetic Imager (HMI). We produce robust, very efficient, professionally coded software modules that can keep up with the SDO data stream and detect, trace, and analyze numerous phenomena, including flares, sigmoids, filaments, coronal dimmings, polarity inversion lines, sunspots, X-ray bright points, active regions, coronal holes, EIT waves, coronal mass ejections (CMEs), coronal oscillations, and jets. We also track the emergence and evolution of magnetic elements down to the smallest detectable features and will provide at least four full-disk, nonlinear, force-free magnetic field extrapolations per day. The detection of CMEs and filaments is accomplished with Solar and Heliospheric Observatory (SOHO)/ Large Angle and Spectrometric Coronagraph (LASCO) and ground-based Hα data, respectively. A completely new software element is a trainable feature-detection module based on a generalized image-classification algorithm. Such a trainable module can be used to find features that have not yet been discovered (as, for example, sigmoids were in the pre- Yohkoh era). Our codes will produce entries in the Heliophysics Events Knowledgebase (HEK) as well as produce complete catalogs for results that are too numerous for inclusion in the HEK, such as the X-ray bright-point metadata. This will permit users to locate data on individual events as well as carry out statistical studies on large numbers of events, using the interface provided by the Virtual Solar Observatory. The operations concept for our computer vision system is that the data will be analyzed in near real time as soon as they arrive at the SDO Joint Science Operations Center and have undergone basic processing. This will allow the system to produce timely space-weather alerts and to guide the selection and production of quicklook images and movies, in addition to its prime mission of enabling solar science. We briefly describe the complex and unique data-processing pipeline, consisting of the hardware and control software required to handle the SDO data stream and accommodate the computer-vision modules, which has been set up at the Lockheed-Martin Space Astrophysics Laboratory (LMSAL), with an identical copy at the Smithsonian Astrophysical Observatory (SAO).
Software Computes Tape-Casting Parameters
NASA Technical Reports Server (NTRS)
deGroh, Henry C., III
2003-01-01
Tcast2 is a FORTRAN computer program that accelerates the setup of a process in which a slurry containing metal particles and a polymeric binder is cast, to a thickness regulated by a doctor blade, onto fibers wound on a rotating drum to make a green precursor of a metal-matrix/fiber composite tape. Before Tcast2, setup parameters were determined by trial and error in time-consuming multiple iterations of the process. In Tcast2, the fiber architecture in the final composite is expressed in terms of the lateral distance between fibers and the thickness-wise distance between fibers in adjacent plies. The lateral distance is controlled via the manner of winding. The interply spacing is controlled via the characteristics of the slurry and the doctor-blade height. When a new combination of fibers and slurry is first cast and dried to a green tape, the shrinkage from the wet to the green condition and a few other key parameters of the green tape are measured. These parameters are provided as input to Tcast2, which uses them to compute the doctor-blade height and fiber spacings needed to obtain the desired fiber architecture and fiber volume fraction in the final composite.
NASA Astrophysics Data System (ADS)
Areeda, J. S.; Smith, J. R.; Lundgren, A. P.; Maros, E.; Macleod, D. M.; Zweizig, J.
2017-01-01
Gravitational-wave observatories around the world, including the Laser Interferometer Gravitational-Wave Observatory (LIGO), record a large volume of gravitational-wave output data and auxiliary data about the instruments and their environments. These data are stored at the observatory sites and distributed to computing clusters for data analysis. LigoDV-web is a web-based data viewer that provides access to data recorded at the LIGO Hanford, LIGO Livingston and GEO600 observatories, and the 40 m prototype interferometer at Caltech. The challenge addressed by this project is to provide meaningful visualizations of small data sets to anyone in the collaboration in a fast, secure and reliable manner with minimal software, hardware and training required of the end users. LigoDV-web is implemented as a Java Enterprise Application, with Shibboleth Single Sign On for authentication and authorization, and a proprietary network protocol used for data access on the back end. Collaboration members with proper credentials can request data be displayed in any of several general formats from any Internet appliance that supports a modern browser with Javascript and minimal HTML5 support, including personal computers, smartphones, and tablets. Since its inception in 2012, 634 unique users have visited the LigoDV-web website in a total of 33 , 861 sessions and generated a total of 139 , 875 plots. This infrastructure has been helpful in many analyses within the collaboration including follow-up of the data surrounding the first gravitational-wave events observed by LIGO in 2015.
NASA Astrophysics Data System (ADS)
Walker, C. E.; Jensen, L.; Pompea, S. M.
2012-12-01
Research interns are using 6 Sky Quality Meters (SQM) around Tucson and 4 more on nearby observatory mountaintops to measure the night sky brightness and characterize its behavior over the entire night over the summer and during the academic school year. The "SQM" devices are inexpensive, yet reliable, computer-free devices, automatically log data, and have housing to protect them from weather. The students download the data onto a computer every few weeks. Two devices are at a central location on the roof of the National Optical Astronomy Observatory (NOAO) and the others are 9 miles N, E, S and W. Four more devices are on observatory mountaintops, namely Mount Lemmon, Mount Hopkins and 2 on Kitt Peak. For the pair of devices at NOAO and on Kitt Peak, one is in the housing unit and the other is exposed to the night sky to track the lossiness of the glass in the housing unit. The SQM is next to the sophisticated and more expensive "Night Sky Brightness Monitor" (NSBM) on Mount Lemmon, Mount Hopkins and, in the future, Kitt Peak. The student interns compare the SQM to the NSBM data on the mountaintops, weather data (temperature and humidity), internal temperature of the SQM, the all-sky camera that is up on Kitt Peak and the SQM results from Tucson. Weather stations already exist very close to all of the locations (usually within a mile or a few feet). We discuss the students' analysis of the data and conclusions as well as the challenges and successes of the program and its plans for expansion.
NASA Astrophysics Data System (ADS)
Wei, Wang; Chongchao, Pan; Yikai, Liang; Gang, Li
2017-11-01
With the rapid development of information technology, the scale of data center increases quickly, and the energy consumption of computer room also increases rapidly, among which, energy consumption of air conditioning cooling makes up a large proportion. How to apply new technology to reduce the energy consumption of the computer room becomes an important topic of energy saving in the current research. This paper study internet of things technology, and design a kind of green computer room environmental monitoring system. In the system, we can get the real-time environment data from the application of wireless sensor network technology, which will be showed in a creative way of three-dimensional effect. In the environment monitor, we can get the computer room assets view, temperature cloud view, humidity cloud view, microenvironment view and so on. Thus according to the condition of the microenvironment, we can adjust the air volume, temperature and humidity parameters of the air conditioning for the individual equipment cabinet to realize the precise air conditioning refrigeration. And this can reduce the energy consumption of air conditioning, as a result, the overall energy consumption of the green computer room will reduce greatly. At the same time, we apply this project in the computer center of Weihai, and after a year of test and running, we find that it took a good energy saving effect, which fully verified the effectiveness of this project on the energy conservation of the computer room.
The TJO-OAdM robotic observatory: OpenROCS and dome control
NASA Astrophysics Data System (ADS)
Colomé, Josep; Francisco, Xavier; Ribas, Ignasi; Casteels, Kevin; Martín, Jonatan
2010-07-01
The Telescope Joan Oró at the Montsec Astronomical Observatory (TJO - OAdM) is a small-class observatory working in completely unattended control. There are key problems to solve when a robotic control is envisaged, both on hardware and software issues. We present the OpenROCS (ROCS stands for Robotic Observatory Control System), an open source platform developed for the robotic control of the TJO - OAdM and similar astronomical observatories. It is a complex software architecture, composed of several applications for hardware control, event handling, environment monitoring, target scheduling, image reduction pipeline, etc. The code is developed in Java, C++, Python and Perl. The software infrastructure used is based on the Internet Communications Engine (Ice), an object-oriented middleware that provides object-oriented remote procedure call, grid computing, and publish/subscribe functionality. We also describe the subsystem in charge of the dome control: several hardware and software elements developed to specially protect the system at this identified single point of failure. It integrates a redundant control and a rain detector signal for alarm triggering and it responds autonomously in case communication with any of the control elements is lost (watchdog functionality). The self-developed control software suite (OpenROCS) and dome control system have proven to be highly reliable.
High Energy Astronomy Observatory (HEAO)
1980-01-01
Like the Crab Nebula, the Vela Supernova Remnant has a radio pulsar at its center. In this image taken by the High Energy Astronomy Observatory (HEAO)-2/Einstein Observatory, the pulsar appears as a point source surrounded by weak and diffused emissions of x-rays. HEAO-2's computer processing system was able to record and display the total number of x-ray photons (a tiny bundle of radiant energy used as the fundamental unit of electromagnetic radiation) on a scale along the margin of the picture. The HEAO-2, the first imaging and largest x-ray telescope built to date, was capable of producing actual photographs of x-ray objects. Shortly after launch, the HEAO-2 was nicknamed the Einstein Observatory by its scientific experimenters in honor of the centernial of the birth of Albert Einstein, whose concepts of relativity and gravitation have influenced much of modern astrophysics, particularly x-ray astronomy. The HEAO-2, designed and developed by TRW, Inc. under the project management of the Marshall Space Flight Center, was launched aboard an Atlas/Centaur launch vehicle on November 13, 1978.
Image of the Vela Supernova Remnant Taken by the High Energy Astronomy Observatory (HEAO)-2
NASA Technical Reports Server (NTRS)
1980-01-01
Like the Crab Nebula, the Vela Supernova Remnant has a radio pulsar at its center. In this image taken by the High Energy Astronomy Observatory (HEAO)-2/Einstein Observatory, the pulsar appears as a point source surrounded by weak and diffused emissions of x-rays. HEAO-2's computer processing system was able to record and display the total number of x-ray photons (a tiny bundle of radiant energy used as the fundamental unit of electromagnetic radiation) on a scale along the margin of the picture. The HEAO-2, the first imaging and largest x-ray telescope built to date, was capable of producing actual photographs of x-ray objects. Shortly after launch, the HEAO-2 was nicknamed the Einstein Observatory by its scientific experimenters in honor of the centernial of the birth of Albert Einstein, whose concepts of relativity and gravitation have influenced much of modern astrophysics, particularly x-ray astronomy. The HEAO-2, designed and developed by TRW, Inc. under the project management of the Marshall Space Flight Center, was launched aboard an Atlas/Centaur launch vehicle on November 13, 1978.
NASA Astrophysics Data System (ADS)
Pelz, M.; Hoeberechts, M.; Ewing, N.; Davidson, E.; Riddell, D. J.
2014-12-01
Schools on Canada's west coast and in the Canadian Arctic are participating in the pilot year of a novel educational program based on analyzing, understanding and sharing ocean data collected by cabled observatories. The core of the program is "local observations, global connections." First, students develop an understanding of ocean conditions at their doorstep through the analysis of community-based observatory data. Then, they connect that knowledge with the health of the global ocean by engaging with students at other schools participating in the educational program and through supplemental educational resources. Ocean Networks Canada (ONC), an initiative of the University of Victoria, operates cabled ocean observatories which supply continuous power and Internet connectivity to a broad suite of subsea instruments from the coast to the deep sea. This Internet connectivity permits researchers, students and members of the public to download freely available data on their computers anywhere around the globe, in near real-time. In addition to the large NEPTUNE and VENUS cabled observatories off the coast of Vancouver Island, British Columbia, ONC has been installing smaller, community-based cabled observatories. Currently two are installed: one in Cambridge Bay, Nunavut and one at Brentwood College School, on Mill Bay in Saanich Inlet, BC. Several more community-based observatories are scheduled for installation within the next year. The observatories support a variety of subsea instruments, such as a video camera, hydrophone and water quality monitor and shore-based equipment including a weather station and a video camera. Schools in communities hosting an observatory are invited to participate in the program, alongside schools located in other coastal and inland communities. Students and teachers access educational material and data through a web portal, and use video conferencing and social media tools to communicate their findings. A series of lesson plans introduces the teachers and students to cabled observatory technology and instrumentation, including technical aspects and their value in monitoring changing ocean conditions. This presentation will describe the program in more detail and report on our experiences in the first months of the pilot year.
Lava and Snow on Klyuchevskaya Volcano [high res
2013-09-20
IDL TIFF file This false-color (shortwave infrared, near infrared, green) satellite image reveals an active lava flow on the western slopes of Klyuchevskaya Volcano. Klyuchevskaya is one of several active volcanoes on the Kamchatka Peninsula in far eastern Russia. The lava flow itself is bright red. Snow on Klyuchevskaya and nearby mountains is cyan, while bare ground and volcanic debris is gray or brown. Vegetation is green. The image was collected by Landsat 8 on September 9, 2013. NASA Earth Observatory image by Jesse Allen and Robert Simmon, using Instrument: Landsat 8 - OLI More info: 1.usa.gov/1evspH7 NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram
Optimizing fixed observational assets in a coastal observatory
NASA Astrophysics Data System (ADS)
Frolov, Sergey; Baptista, António; Wilkin, Michael
2008-11-01
Proliferation of coastal observatories necessitates an objective approach to managing of observational assets. In this article, we used our experience in the coastal observatory for the Columbia River estuary and plume to identify and address common problems in managing of fixed observational assets, such as salinity, temperature, and water level sensors attached to pilings and moorings. Specifically, we addressed the following problems: assessing the quality of an existing array, adding stations to an existing array, removing stations from an existing array, validating an array design, and targeting of an array toward data assimilation or monitoring. Our analysis was based on a combination of methods from oceanographic and statistical literature, mainly on the statistical machinery of the best linear unbiased estimator. The key information required for our analysis was the covariance structure for a field of interest, which was computed from the output of assimilated and non-assimilated models of the Columbia River estuary and plume. The network optimization experiments in the Columbia River estuary and plume proved to be successful, largely withstanding the scrutiny of sensitivity and validation studies, and hence providing valuable insight into optimization and operation of the existing observational network. Our success in the Columbia River estuary and plume suggest that algorithms for optimal placement of sensors are reaching maturity and are likely to play a significant role in the design of emerging ocean observatories, such as the United State's ocean observation initiative (OOI) and integrated ocean observing system (IOOS) observatories, and smaller regional observatories.
NRAO Scientists on Team Receiving International Astronautics Award
NASA Astrophysics Data System (ADS)
2005-10-01
The International Academy of Astronautics (IAA) is presenting an award to a pioneering team of scientists and engineers who combined an orbiting radio-astronomy satellite with ground-based radio telescopes around the world to produce a "virtual telescope" nearly three times the size of the Earth. The team, which includes two scientists from the National Radio Astronomy Observatory (NRAO), will receive the award in a ceremony Sunday, October 16, in Fukuoka, Japan. VSOP Satellite and Ground Telescopes Artist's conception of HALCA satellite and ground observatories together making "virtual telescope" (blue) about three times the size of Earth. CREDIT: ISAS, JAXA (Click on image for larger version) The IAA chose the VLBI Space Observatory Program (VSOP), an international collaboration, to receive its 2005 Laurels for Team Achievement Award, which recognizes "extraordinary performance and achievement by a team of scientists, engineers and managers in the field of Astronautics to foster its peaceful and international use." VSOP team members named in the IAA award include NRAO astronomers Edward Fomalont, of Charlottesville, Virginia, and Jonathan Romney, of Socorro, New Mexico. "This is a well-deserved award for an international team whose hard work produced a scientific milestone that yielded impressive results and provides a foundation for more advances in the future," said Dr. Fred K.Y Lo, NRAO Director. The VSOP program used a Japanese satellite, HALCA (Highly Advanced Laboratory for Communications and Astronomy), that included an 8-meter (26-foot) radio telescope. HALCA was launched in 1997 and made astronomical observations in conjunction with ground-based radio telescopes from 14 countries. Five tracking stations, including one at NRAO's Green Bank, West Virginia, facility, received data from HALCA which later was combined with data from the ground-based telescopes to produce images more detailed than those that could have been made by ground-based systems alone. The NRAO's Very Long Baseline Array (VLBA), a continent-wide system of radio telescopes ranging from Hawaii to the Caribbean, was one of the principal ground-based networks working with HALCA. The VLBA's powerful special-purpose computer, called a correlator, was a prime workhorse for processing the data from VSOP astronomical observations. Very long baseline interferometry (VLBI) is a technique used by radio astronomers to electronically link widely separated radio telescopes together so they work as if they were a single instrument with extraordinarily sharp "vision," or resolving power. The wider the distance, or "baselines" between telescopes, the greater the resolving power. The IAA award citation notes that the VSOP team "realized the long-held dream of radio astronomers to extend those baselines into space, by observing celestial radio sources with the HALCA satellite, supported by a dedicated network of tracking stations, and arrays of ground radio telescopes from around the world." The VSOP team was able to approximately triple the resolving power available with only ground-based telescopes. The first experiment in such space-ground observation was made in 1986, using a NASA Tracking and Data Relay Satellite. The VSOP project grew as an international effort after that experiment, and provided observing time to astronomers from around the world. During the VSOP observational program, the combined space-ground system made more than 780 individual astronomical observations and also made an all-sky survey of the cores of active galaxies. The VLBA The VLBA CREDIT: NRAO/AUI/NSF In addition to providing large amounts of observing time on the VLBA and building and operating the Green Bank tracking station, NRAO staff also modified existing hardware and software and aided astronomers from around the world in analyzing VSOP data. On behalf of the entire VSOP Team, the IAA highlighted "the astronomers and engineers who made key contributions to realizing, and operating, a radio telescope bigger than the Earth." In addition to Fomalont and Romney, they are: Hisashi Hirabayashi, of the Institute of Space and Astronautical Science and Japan Aerospace Exploration Agency (ISAS/JAXA), Haruto Hirosawa (ISAS/JAXA), Peter Dewdney of Canada's Dominion Radio Astrophysical Observatory, Leonid Gurvits of the Joint Institute for VLBI in Europe (JIVE, The Netherlands), Makoto Inoue of the National Astronomical Observatory of Japan (NAOJ), David Jauncey of the Australia Telescope National Facility, Noriyuki Kawaguchi (NAOJ), Hideyuki Kobayashi (NAOJ), Kazuo Miyoshi (Mitsubishi Electric Corporation, Japan), Yasuhiro Murata (ISAS/JAXA), Takeshi Orii (NEC, Japan) Robert Preston of NASA's Jet Propulsion Laboratory (JPL), and Joel Smith (JPL). The International Academy of Astronautics was founded in August 1960 in Stockholm, Sweden, during the 11th International Astronautical Congress. The Academy aims to foster the development of astronautics for peaceful purposes; recognize individuals who have distinguished themselves in a related branch of science or technology; provide a program through which members may contribute to international endeavours; cooperation in the advancement of aerospace science. Previous recipients of the Laurels for Team Achievement Award are the Russian Mir Space Station Team (2001), the U.S. Space Shuttle Team (2002), the Solar and Heliospheric Observatory (SOHO) Team (2003), and the Hubble Space Telescope Team (2004). The National Radio Astronomy Observatory is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc.
Automation of Precise Time Reference Stations (PTRS)
NASA Astrophysics Data System (ADS)
Wheeler, P. J.
1985-04-01
The U.S. Naval Observatory is presently engaged in a program of automating precise time stations (PTS) and precise time reference stations (PTBS) by using a versatile mini-computer controlled data acquisition system (DAS). The data acquisition system is configured to monitor locally available PTTI signals such as LORAN-C, OMEGA, and/or the Global Positioning System. In addition, the DAS performs local standard intercomparison. Computer telephone communications provide automatic data transfer to the Naval Observatory. Subsequently, after analysis of the data, results and information can be sent back to the precise time reference station to provide automatic control of remote station timing. The DAS configuration is designed around state of the art standard industrial high reliability modules. The system integration and software are standardized but allow considerable flexibility to satisfy special local requirements such as stability measurements, performance evaluation and printing of messages and certificates. The DAS operates completely independently and may be queried or controlled at any time with a computer or terminal device (control is protected for use by authorized personnel only). Such DAS equipped PTS are operational in Hawaii, California, Texas and Florida.
VO-KOREL: A Fourier Disentangling Service of the Virtual Observatory
NASA Astrophysics Data System (ADS)
Škoda, Petr; Hadrava, Petr; Fuchs, Jan
2012-04-01
VO-KOREL is a web service exploiting the technology of the Virtual Observatory for providing astronomers with the intuitive graphical front-end and distributed computing back-end running the most recent version of the Fourier disentangling code KOREL. The system integrates the ideas of the e-shop basket, conserving the privacy of every user by transfer encryption and access authentication, with features of laboratory notebook, allowing the easy housekeeping of both input parameters and final results, as well as it explores a newly emerging technology of cloud computing. While the web-based front-end allows the user to submit data and parameter files, edit parameters, manage a job list, resubmit or cancel running jobs and mainly watching the text and graphical results of a disentangling process, the main part of the back-end is a simple job queue submission system executing in parallel multiple instances of the FORTRAN code KOREL. This may be easily extended for GRID-based deployment on massively parallel computing clusters. The short introduction into underlying technologies is given, briefly mentioning advantages as well as bottlenecks of the design used.
Approximate Green's function methods for HZE transport in multilayered materials
NASA Technical Reports Server (NTRS)
Wilson, John W.; Badavi, Francis F.; Shinn, Judy L.; Costen, Robert C.
1993-01-01
A nonperturbative analytic solution of the high charge and energy (HZE) Green's function is used to implement a computer code for laboratory ion beam transport in multilayered materials. The code is established to operate on the Langley nuclear fragmentation model used in engineering applications. Computational procedures are established to generate linear energy transfer (LET) distributions for a specified ion beam and target for comparison with experimental measurements. The code was found to be highly efficient and compared well with the perturbation approximation.
Exploring the Digital Universe with Europe's Astrophysical Virtual Observatory
NASA Astrophysics Data System (ADS)
2001-12-01
Vast Databanks at the Astronomers' Fingertips Summary A new European initiative called the Astrophysical Virtual Observatory (AVO) is being launched to provide astronomers with a breathtaking potential for new discoveries. It will enable them to seamlessly combine the data from both ground- and space-based telescopes which are making observations of the Universe across the whole range of wavelengths - from high-energy gamma rays through the ultraviolet and visible to the infrared and radio. The aim of the Astrophysical Virtual Observatory (AVO) project, which started on 15 November 2001, is to allow astronomers instant access to the vast databanks now being built up by the world's observatories and which are forming what is, in effect, a "digital sky" . Using the AVO, astronomers will, for example, be able to retrieve the elusive traces of the passage of an asteroid as it passes near the Earth and so enable them to predict its future path and perhaps warn of a possible impact. When a giant star comes to the end of its life in a cataclysmic explosion called a supernova, they will be able to access the digital sky and pinpoint the star shortly before it exploded so adding invaluable data to the study of the evolution of stars. Background information on the Astrophysical Virtual Observatory is available in the Appendix. PR Photo 34a/01 : The Astrophysical Virtual Observatory - an artist's impression. The rapidly accumulating database ESO PR Photo 34a/01 ESO PR Photo 34a/01 [Preview - JPEG: 400 x 345 pix - 90k] [Normal - JPEG: 800 x 689 pix - 656k] [Hi-Res - JPEG: 3000 x 2582 pix - 4.3M] ESO PR Photo 34a/01 shows an artist's impression of the Astrophysical Virtual Observatory . Modern observatories observe the sky continuously and data accumulates remorselessly in the digital archives. The growth rate is impressive and many hundreds of terabytes of data - corresponding to many thousands of billions of pixels - are already available to scientists. The real sky is being digitally reconstructed in the databanks! The richness and complexity of data and information available to the astronomers is overwhelming. This has created a major problem as to how astronomers can manage, distribute and analyse this great wealth of data . The Astrophysical Virtual Observatory (AVO) will allow astronomers to overcome the challenges and enable them to "put the Universe online". AVO is supported by the European Commission The AVO is a three-year project, funded by the European Commission under its Research and Technological Development (RTD) scheme, to design and implement a virtual observatory for the European astronomical community. The European Commission awarded a contract valued at 4 million Euro for the AVO project , starting 15 November 2001. AVO will provide software tools to enable astronomers to access the multi-wavelength data archives over the Internet and so give them the capability to resolve fundamental questions about the Universe by probing the digital sky. Equivalent searches of the 'real' sky would, in comparison, be both costly and take far too long. Towards a Global Virtual Observatory The need for virtual observatories has also been recognised by other astronomical communities. The National Science Foundation in the USA has awarded 10 million Dollar (approx. 11.4 million Euro) for a National Virtual Observatory (NVO). The AVO project team has formed a close alliance with the NVO and both teams have representatives on their respective committees. It is clear to the NVO and AVO communities that there are no intrinsic boundaries to the virtual observatory concept and that all astronomers should be working towards a truly global virtual observatory that will enable new science to be carried out on the wealth of astronomical data held in the growing number of first class international astronomical archives. The AVO involves six partner organisations led by the European Southern Observatory (ESO) in Munich (Germany). The other partner organisations are the European Space Agency (ESA) , the United Kingdom's ASTROGRID consortium, the CNRS-supported Centre de Données Astronomiques de Strasbourg (CDS) at the University Louis Pasteur in Strasbourg (France), the CNRS-supported TERAPIX astronomical data centre at the Institut d'Astrophysique in Paris and the Jodrell Bank Observatory of the Victoria University of Manchester (UK). Note [1]: This is a joint Press Release issued by the European Southern Observatory (ESO), the Hubble European Space Agency Information Centre, ASTROGRID, CDS, TERAPIX/CNRS and the University of Manchester. A 13 minute background video (broadcast PAL) is available from ESO PR and the Hubble European Space Agency Information Centre (addresses below). This will also be transmitted via satellite Wednesday 12 December 2001 from 12:00 to 12:15 CET on "ESA TV Service", cf. http://television.esa.int. An international conference, "Toward an International Virtual Observatory" will take place at ESO (Garching, Germany) on June 10 - 14, 2002. Contacts AVO Contacts Peter Quinn European Southern Observatory Garching, Germany Tel.: +4989-3200-6509 email: pjq@eso.org Piero Benvenuti Space Telescope-European Coordinating Facility Garching, Germany Tel.: +49-89-3200-6290 email: pbenvenu@eso.org Andy Lawrence (on behalf of The ASTROGRID Consortium) Institute for Astronomy University of Edinburgh United Kingdom Tel.: +44-131-668-8346/56 email: al@roe.ac.uk Francoise Genova Centre de Données Astronomiques de Strasbourg (CDS) France Tel.: +33-390-24-24-76 email: genova@astro.u-strasbg.fr Yannick Mellier CNRS, Delegation Paris A (CNRSDR01-Terapix)/IAP/INSU France Tel.: +33-1-44-32-81-40 email: mellier@iap.fr Phil Diamond University of Manchester/Jodrell Bank Observatory United Kingdom Tel.: +44-147-757-2625 email: pdiamond@jb.man.ac.uk PR Contacts Richard West European Southern Observatory Garching, Germany Tel.: +49-89-3200-6276 email: rwest@eso.org Lars Lindberg Christensen Hubble European Space Agency Information Centre Garching, Germany Tel.: +49-89-3200-6306 or +49-173-38-72-621 email: lars@eso.org Ray Footman The ASTROGRID Consortium/University of Edinburgh United Kingdom Tel.: +44-131-650-2249 email: r.footman@ed.ac.uk Philippe Chauvin Terapix/CDS CNRS, Delegation Paris A, IAP/INSU France Tel.: +33 1 44 96 43 36 email: philippe.chauvin@cnrs-dir.fr Agnes Villanueva University of Strasbourg France Tel.: +33 3 90 24 11 35 email: agnes.villanueva@adm-ulp.u-strasbg.fr Ian Morison University of Manchester/Jodrell Bank Observatory United Kingdom Tel.: +44 1477 572610 email: im@jb.man.ac.uk Appendix: Introduction to Europe's Astrophysical Virtual Observatory (AVO) The Digital Data Revolution Over the past thirty years, astronomers have moved from photographic and analogue techniques towards the use of high-speed, digital instruments connected to specialised telescopes to study the Universe. Whether these instruments are onboard spacecraft or located at terrestrial observatories, the data they produce are stored digitally on computer systems for later analysis. Two Challenges This data revolution has created two challenges for astronomers. Firstly, as the capability of digital detector systems has advanced, the volume of digital data that astronomical facilities are producing has expanded greatly. The rate of growth of the volume of stored data far exceeds the rate of increase in the performance of computer systems or storage devices. Secondly, astronomers have realised that many important insights into the deepest secrets in the Universe can come from combining information obtained at many wavelengths into a consistent and comprehensive physical picture . However, because the datasets from different parts of the spectrum come from different observatories using different instruments, the data are not easily combined. To unite data from different observatories, bridges must be built between digital archives to allow them to share data and "interoperate" - an important and challenging task. The Human Factor These challenges are not only technological. Our brains are not equipped to for instance analyse simultaneously the millions and millions of images available. Astronomers must adapt and learn to deal with such diverse and extensive sets of data. The "digital sky" has the potential to become a vital tool with novel and fascinating capabilities that are essential for astronomers to make progress in their understanding of the Cosmos. But astronomers must be able to find the relevant information quickly and efficiently. Currently the data needed by a particular research program may well be stored in the archives already, but the tools and methods have not yet been developed to extract the relevant information from the flood of images available. A new way of thinking, a new frame of mind and a new approach are needed. The Astrophysical Virtual Observatory The Astrophysical Virtual Observatory (AVO) will allow astronomers to overcome the challenges and extract data from the digital sky, thus "putting the Universe online" . Like a search engine helps us to find information on the Internet, astronomers need sophisticated "search engines" as well as other tools to find and interpret the information. "We're drowning in information and starving for knowledge", a Yale University librarian once said. Or to paraphrase a popular series on TV: "The information is out there, but you have to find it!" Using the latest in computer technology, data storage and analysis techniques, AVO will maximise the potential for new scientific insights from the stored data by making them available in a readily accessible and seamlessly unified form to professional researchers, amateur astronomers and students. Users of AVO will have immense multi-wavelength vistas of the digital Universe at their fingertips and the potential to make breathtaking new discoveries. Virtual observatories signal a new era, where data collected by a multitude of sophisticated telescopes can be used globally and repeatedly to achieve substantial progress in the quest for knowledge. The AVO project, funded by the European Commission, is a three-year study of the design and implementation of a virtual observatory for European astronomy. A virtual observatory is a collection of connected data archives and software tools that utilise the Internet to form a scientific research environment in which new multi-wavelength astronomical research programs can be conducted. In much the same way as a real observatory consists of telescopes, each with a collection of unique astronomical instruments, the virtual observatory consists of a collection of data centres each with unique collections of astronomical data, software systems and processing capabilities. The programme will implement and test a prototype virtual observatory , focussing on the key areas of scientific requirements, interoperability and new technologies such as the GRID, needed to link powerful computers to the newly formed large data repositories. The GRID and the Future of the Internet The technical problems astronomers have to solve are similar to those being worked on by particle physicists, by biologists, and by commercial companies who want to search and fill customer databases across the world. The emerging idea is that of the GRID where computers collaborate across the Internet. The World Wide Web made words and pictures available to anybody at the click of a mouse. The GRID will do the same for data, and for computer processing power. Anybody can have the power of a supercomputer sitting on their desktop. The Astrophysical Virtual Observatory, and GRID projects like the ASTROGRID project in the United Kingdom (funding 5 million UK Pounds or 8 million Euro), are closely linked to these developments.
Books: Not just computers and companions
NASA Astrophysics Data System (ADS)
2009-08-01
Mary Brück's historical survey is the second RAS Series publication, and one that gives an insight into the different roles taken by women astronomers: original thinkers, computers, educators, and entrepreneurs. In this extract from the chapter ``The Labyrinths of Heaven'', we find out how Maria Short (c1788-1869) came to own and operate an observatory open to the public in the mid-19th century.
History of Chandra X-Ray Observatory
2002-07-31
This is a photo taken by NASA's Chandra X-ray Observatory that reveals the remains of an explosion in the form of two enormous arcs of multimillion-degree gas in the galaxy Centaurus A that appear to be part of a ring 25,000 light years in diameter. The size and location of the ring suggest that it could have been an explosion that occurred about 10 million years ago. A composite image made with radio (red and green), optical (yellow-orange), and X-ray data (blue) presents a sturning tableau of a turbulent galaxy. A broad band of dust and cold gas is bisected at an angle by opposing jets of high-energy particles blasting away from the supermassive black hole in the nucleus. Lying in a plane perpendicular to the jets are the two large arcs of x-ray emitting multi-million degree gas. This discovery can help astronomers better understand the cause and effect of violent outbursts from the vicinity of supermassive black holes of active galaxies. The Chandra program is managed by the Marshall Space Flight Center in Huntsville, Alabama.
History of Chandra X-Ray Observatory
2000-10-01
This most distant x-ray cluster of galaxies yet has been found by astronomers using Chandra X-ray Observatory (CXO). Approximately 10 billion light-years from Earth, the cluster 3C294 is 40 percent farther than the next most distant x-ray galaxy cluster. The existence of such a faraway cluster is important for understanding how the universe evolved. CXO's image reveals an hourglass-shaped region of x-ray emissions centered on the previously known central radio source (seen in this image as the blue central object) that extends outward for 60,000 light- years. The vast clouds of hot gas that surround such galaxies in clusters are thought to be heated by collapse toward the center of the cluster. Until CXO, x-ray telescopes have not had the needed sensitivity to identify such distant clusters of galaxies. Galaxy clusters are the largest gravitationally bound structures in the universe. The intensity of the x-rays in this CXO image of 3C294 is shown as red for low energy x-rays, green for intermediate, and blue for the most energetic x-rays. (Photo credit: NASA/loA/A. Fabian et al)
CARMENES: management of a schedule-driven project
NASA Astrophysics Data System (ADS)
García-Vargas, M. L.; Caballero, J.; Pérez-Calpena, A.; Amado, Pedro; Seifert, Walter; Azzaro, Marco; Mandel, Holger; Quirrenbach, Andreas; Ribas, Ignasi; Reiners, Ansgar; Guenther, Eike; Gesa, Lluís.; Galadí, David; Aceituno, Jesús
2016-08-01
CARMENES (Calar Alto high-Resolution search for M dwarfs with Exoearths with Near-infrared and optical Échelle Spectrographs) is an instrument consistent in two ultra-stable high resolution (R 82,000) spectrographs covering simultaneously the visible (0.5 - 1.0μm) and near-IR (1.0 - 1.7μm) ranges to provide high-accuracy radial-velocity measurements (˜1 m/s) thanks to the long-term stability. CARMENES was the initiative of a consortium of eleven German and Spanish institutions. CARMENES has been built for the 3.5m telescope at the Centro Astronómico Hipano- Alemán (CAHA), Calar Alto Observatory (Almería, Spain) and is currently in operation. CAHA is jointly operated by the Max-Planck-Society (MPG) and the Spanish National Research Council (CSIC). The project received the green light in October 2010 and in February 2013 passed a Final Design Review. Six months later, the MPG and CSIC, the observatory's owners, made an independent evaluation concluding that CARMENES had to be ready for operations at the end of 2015. Since then, fulfilling the calendar was the driver of all project decisions. Moreover, the observatory's survival was linked to the instrument's success: should the instrument fail, the observatory would be closed. On the contrary, the instrument's success would give unique capabilities to the Observatory for Big Science. Such a challenge became to be our private Olympic Games: we had to be on time. This decision definitively impacted on the project dynamics, there was no room for a delay. The deadline, December 31st, 2015, was controlled by a strict tracking of the critical path; calendar deviations were corrected with risky decisions while fast tracking or even crashing methods were applied. The management scenario was far from optimum: most key people in the project shared their time with other duties; the observatory funding cuts; the budget was tight and distributed among the 11 partner centers with their own different rules, etc. Despite these difficulties, the close coordination among the project manager, the system engineer and the work package managers, the hard work of the whole team, and the support from the observatory were our best bets. Two frenetic years after the calendar decision, we had manufactured, integrated and tested the two spectrographs and we were commissioning the instrument. The instrument first light took place on November, 9th, 2015 and CARMENES entered in operation at the end of December 2015. This paper describes the keys to success.
Michielsen, K; De Raedt, H; Stavenga, D G
2010-05-06
We present a comparison of the computer simulation data of gyroid nanostructures with optical measurements (reflectivity spectra and scattering diagrams) of ventral wing scales of the Green Hairstreak butterfly, Callophrys rubi. We demonstrate that the omnidirectional green colour arises from the gyroid cuticular structure grown in the domains of different orientation. We also show that this three-dimensional structure, operating as a biophotonic crystal, gives rise to various polarization effects. We briefly discuss the possible biological utility of the green coloration and polarization effects.
Evolution of the SOFIA tracking control system
NASA Astrophysics Data System (ADS)
Fiebig, Norbert; Jakob, Holger; Pfüller, Enrico; Röser, Hans-Peter; Wiedemann, Manuel; Wolf, Jürgen
2014-07-01
The airborne observatory SOFIA (Stratospheric Observatory for Infrared Astronomy) is undergoing a modernization of its tracking system. This included new, highly sensitive tracking cameras, control computers, filter wheels and other equipment, as well as a major redesign of the control software. The experiences along the migration path from an aged 19" VMbus based control system to the application of modern industrial PCs, from VxWorks real-time operating system to embedded Linux and a state of the art software architecture are presented. Further, the concept is presented to operate the new camera also as a scientific instrument, in parallel to tracking.
A knowledge-based expert system for scheduling of airborne astronomical observations
NASA Technical Reports Server (NTRS)
Nachtsheim, P. R.; Gevarter, W. B.; Stutz, J. C.; Banda, C. P.
1985-01-01
The Kuiper Airborne Observatory Scheduler (KAOS) is a knowledge-based expert system developed at NASA Ames Research Center to assist in route planning of a C-141 flying astronomical observatory. This program determines a sequence of flight legs that enables sequential observations of a set of heavenly bodies derived from a list of desirable objects. The possible flight legs are constrained by problems of observability, avoiding flyovers of warning and restricted military zones, and running out of fuel. A significant contribution of the KAOS program is that it couples computational capability with a reasoning system.
Astronomy and astrophysics for the 1980's, volume 1
NASA Technical Reports Server (NTRS)
1982-01-01
The programs recommended address the most significant questions that confront contemporary astronomy and fall into three general categories: prerequisites for research initiatives, including instrumentation and detectors, theory and data analysis, computational facilities, laboratory astrophysics, and technical support at ground-based observatories; programs including an Advanced X-ray Astrophysics Facility, a Very-Long Baseline Array, a Technology Telescope and a Large Deployable Reflector; and programs for study and development, including X-ray observatories in space, instruments for the detection of gravitational waves from astronomical objects, and long duration spaceflights of infrared telescopes. Estimated costs of these programs are provided.
The development, deployment, and impact of the virtual observatory, Part II
NASA Astrophysics Data System (ADS)
Hanisch, R. J.
2015-06-01
This is the second special issue of Astronomy and Computing devoted to the Virtual Observatory, and we again see a combination of papers covering various aspects of the VO, from infrastructure to applications to programmatics. The critical role of data models is described by Louys, and the method by which applications communicate amongst each other through the Simple Applications Messaging Protocol (SAMP) is described by Taylor et al. Demleitner et al. explain the client interfaces to the VO registry, that is, how applications developers can query the registry for information about VO-compliant data collections and services.1
Astronomy and astrophysics for the 1980's, volume 1
NASA Astrophysics Data System (ADS)
The programs recommended address the most significant questions that confront contemporary astronomy and fall into three general categories: prerequisites for research initiatives, including instrumentation and detectors, theory and data analysis, computational facilities, laboratory astrophysics, and technical support at ground-based observatories; programs including an Advanced X-ray Astrophysics Facility, a Very-Long Baseline Array, a Technology Telescope and a Large Deployable Reflector; and programs for study and development, including X-ray observatories in space, instruments for the detection of gravitational waves from astronomical objects, and long duration spaceflights of infrared telescopes. Estimated costs of these programs are provided.
Multiple-etalon systems for the Advanced Technology Solar Telescope
NASA Technical Reports Server (NTRS)
Gary, G. Allen; Balasubramaniam, K. S.; Sigwarth, Michael
2003-01-01
Multiple etalon systems are discussed that meet the science requirements for a narrow-passband imaging system for the 4-meter National Solar Observatory (NSO)/Advance Technology Solar Telescope (ATST). A multiple etalon system can provide an imaging interferometer that works in four distinct modes: as a spectro-polarimeter, a filter-vector magnetograph, an intermediate-band imager, and broadband high-resolution imager. Specific dual and triple etalon configurations are described that provide a spectrographic passband of 2.0-3.5 micron and reduce parasitic light levels to 10(exp -4) as required for precise polarization measurement, e.g., Zeeman measurements of magnetic sensitive lines. A TESOS-like (Telecentric Etalon SOlar Spectrometer) triple etalon system provides a spectral purity of 10(exp -5). The triple designs have the advantage of reducing the finesse requirement on each etalon; allow the use of more stable blocking filters, and have very high spectral purity. A dual-etalon double-pass (Cavallini-like) system can provide a competing configuration. Such a dual-etalon design can provide high contrast. The selection of the final focal plane instrument will depend on a trade-off between an ideal instrument and practical reality. The trade study will include the number of etalons, their aperture sizes, complexities of the optical train, number of blocking filters, configuration of the electronic control system, computer interfaces, temperature controllers, etalon controllers, and their associated feedback electronics. The heritage of single and multiple etalon systems comes from their use in several observatories, including the Marshall Space Flight Center (MSFC) Solar Observatory, Sacramento Peak Observatory (NSO), and Kiepenheuer-Institut fur Sonnenphysik (KIS, Germany), Mees Solar Observatory (University of Hawaii), and Arcetri Astrophysical Observatory (Italy). The design of the ATST multiple etalon system will benefit from the experience gained at these observatories.
Bastrop County Complex Fire Burn Scar
2017-12-08
NASA image acquired September 12, 2011 To view more images from this event go to: earthobservatory.nasa.gov/NaturalHazards/event.php?id=52029 The Bastrop County Complex Fire in southern Texas started on September 4, 2011. By September 13, 2011, the fire was 70 percent contained, but had scorched 34,068 acres (13,787 hectares). The Advanced Land Imager (ALI) on NASA’s Earth Observing-1 (EO-1) satellite captured this image of the affected region on September 12, 2011. This false-color image shows a wide-area view of the fire. Vegetation is bright green, and sparsely vegetated or bare land is green-yellow. The burn scar appears in shades of red and orange. The burn scar is far from uniform; burned areas are separated by unburned expanses. As of September 13, a re-entry plan had been established for residents of the region, the Incident Information System reported. Residents were warned, however, that they might see vegetation still smoldering or burning. Ongoing drought set the stage for severe fires in Texas in the slate summer of 2011. In early September, Tropical Storm Lee, which drenched other parts of the United States, brought strong winds to Texas, worsening the fires. NASA Earth Observatory image created by Jesse Allen and Robert Simmon, using EO-1 ALI data provided courtesy of the NASA EO-1 team. Caption by Michon Scott. Instrument: EO-1 - ALI Credit: NASA Earth Observatory NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram
Computation of the area in the discrete plane: Green's theorem revisited
NASA Astrophysics Data System (ADS)
Chalifour, Alain; Nouboud, Fathallah; Voisin, Yvon
2017-11-01
The detection of the contour of a binary object is a common problem; however, the area of a region, and its moments, can be a significant parameter. In several metrology applications, the area of planar objects must be measured. The area is obtained by counting the pixels inside the contour or using a discrete version of Green's formula. Unfortunately, we obtain the area enclosed by the polygonal line passing through the centers of the pixels along the contour. We present a modified version of Green's theorem in the discrete plane, which allows for the computation of the exact area of a two-dimensional region in the class of polyominoes. Penalties are introduced and associated with each successive pair of Freeman displacements along the contour in an eight-connectivity system. The proposed equation is shown to be true and properties of the equation related to the topology of the regions are presented. The proposed approach is adapted for faster computation than the combinatorial approach proposed in the literature.
Integrating Data Distribution and Data Assimilation Between the OOI CI and the NOAA DIF
NASA Astrophysics Data System (ADS)
Meisinger, M.; Arrott, M.; Clemesha, A.; Farcas, C.; Farcas, E.; Im, T.; Schofield, O.; Krueger, I.; Klacansky, I.; Orcutt, J.; Peach, C.; Chave, A.; Raymer, D.; Vernon, F.
2008-12-01
The Ocean Observatories Initiative (OOI) is an NSF funded program to establish the ocean observing infrastructure of the 21st century benefiting research and education. It is currently approaching final design and promises to deliver cyber and physical observatory infrastructure components as well as substantial core instrumentation to study environmental processes of the ocean at various scales, from coastal shelf-slope exchange processes to the deep ocean. The OOI's data distribution network lies at the heart of its cyber- infrastructure, which enables a multitude of science and education applications, ranging from data analysis, to processing, visualization and ontology supported query and mediation. In addition, it fundamentally supports a class of applications exploiting the knowledge gained from analyzing observational data for objective-driven ocean observing applications, such as automatically triggered response to episodic environmental events and interactive instrument tasking and control. The U.S. Department of Commerce through NOAA operates the Integrated Ocean Observing System (IOOS) providing continuous data in various formats, rates and scales on open oceans and coastal waters to scientists, managers, businesses, governments, and the public to support research and inform decision-making. The NOAA IOOS program initiated development of the Data Integration Framework (DIF) to improve management and delivery of an initial subset of ocean observations with the expectation of achieving improvements in a select set of NOAA's decision-support tools. Both OOI and NOAA through DIF collaborate on an effort to integrate the data distribution, access and analysis needs of both programs. We present details and early findings from this collaboration; one part of it is the development of a demonstrator combining web-based user access to oceanographic data through ERDDAP, efficient science data distribution, and scalable, self-healing deployment in a cloud computing environment. ERDDAP is a web-based front-end application integrating oceanographic data sources of various formats, for instance CDF data files as aggregated through NcML or presented using a THREDDS server. The OOI-designed data distribution network provides global traffic management and computational load balancing for observatory resources; it makes use of the OpenDAP Data Access Protocol (DAP) for efficient canonical science data distribution over the network. A cloud computing strategy is the basis for scalable, self-healing organization of an observatory's computing and storage resources, independent of the physical location and technical implementation of these resources.
Application of green IT for physics data processing at INCDTIM
NASA Astrophysics Data System (ADS)
Farcas, Felix; Trusca, Radu; Albert, Stefan; Szabo, Izabella; Popeneciu, Gabriel
2012-02-01
Green IT is the next generation technology used in all datacenter around the world. Its benefit is of economic and financial interest. The new technologies are energy efficient, reduce cost and avoid potential disruptions to the existing infrastructure. The most important problem appears at the cooling systems which are the most important in the functionality of a datacenter. Green IT used in Grid Network will benefit the environment and is the next phase in computer infrastructure that will fundamentally change the way we think about and use computing power. At the National Institute for Research and Development of Isotopic and Molecular Technologies Cluj-Napoca (INCDTIM) we have implemented such kind of technology and its support helped us in processing multiple data in different domains, which brought INCDTIM on the major Grid domain with the RO-14-ITIM Grid site. In this paper we present benefits that the new technology brought us and the result obtained in the last year after the implementation of the new green technology.
NASA Astrophysics Data System (ADS)
Masetti, N.; Mason, E.; Morelli, L.; Cellone, S. A.; McBride, V. A.; Palazzi, E.; Bassani, L.; Bazzano, A.; Bird, A. J.; Charles, P. A.; Dean, A. J.; Galaz, G.; Gehrels, N.; Landi, R.; Malizia, A.; Minniti, D.; Panessa, F.; Romero, G. E.; Stephen, J. B.; Ubertini, P.; Walter, R.
2008-04-01
Using 8 telescopes in the northern and southern hemispheres, plus archival data from two on-line sky surveys, we performed a systematic optical spectroscopic study of 39 putative counterparts of unidentified or poorly studied INTEGRAL sources in order to determine or at least better assess their nature. This was implemented within the framework of our campaign to reveal the nature of newly-discovered and/or unidentified sources detected by INTEGRAL. Our results show that 29 of these objects are active galactic nuclei (13 of which are of Seyfert 1 type, 15 are Seyfert 2 galaxies and one is possibly a BL Lac object) with redshifts between 0.011 and 0.316, 7 are X-ray binaries (5 with high-mass companions and 2 with low-mass secondaries), one is a magnetic cataclysmic variable, one is a symbiotic star and one is possibly an active star. Thus, the large majority (74%) of the identifications in this sample belongs to the AGN class. When possible, the main physical parameters for these hard X-ray sources were also computed using the multiwavelength information available in the literature. These identifications further underscore the importance of INTEGRAL in studying the hard X-ray spectra of all classes of X-ray emitting objects, and the effectiveness of a strategy of multi-catalogue cross-correlation plus optical spectroscopy to securely pinpoint the actual nature of still unidentified hard X-ray sources. Based on observations collected at the following observatories: ESO (La Silla, Chile), partly under program 079.A-0171(A); Astronomical Observatory of Bologna in Loiano (Italy); Astronomical Observatory of Asiago (Italy); Cerro Tololo Interamerican Observatory (Chile); Complejo Astronómico El Leoncito (San Juan, Argentina); South African Astronomical Observatory (Sutherland, South Africa); Observatorio del Roque de los Muchachos of the Instituto de Astrofísica de Canarias (Canary Islands, Spain); Anglo-Australian Observatory (Siding Spring, Australia); Apache Point Observatory (New Mexico, USA).
NASA Astrophysics Data System (ADS)
Ali, Mufajjul
This paper proposes a Green Cloud model for mobile Cloud computing. The proposed model leverage on the current trend of IaaS (Infrastructure as a Service), PaaS (Platform as a Service) and SaaS (Software as a Service), and look at new paradigm called "Network as a Service" (NaaS). The Green Cloud model proposes various Telco's revenue generating streams and services with the CaaS (Cloud as a Service) for the near future.
Los Alamos Fires From Landsat 7
NASA Technical Reports Server (NTRS)
2002-01-01
On May 9, 2000, the Landsat 7 satellite acquired an image of the area around Los Alamos, New Mexico. The Landsat 7 satellite acquired this image from 427 miles in space through its sensor called the Enhanced Thematic Mapper Plus (ETM+). Evident within the imagery is a view of the ongoing Cerro Grande fire near the town of Los Alamos and the Los Alamos National Laboratory. Combining the high-resolution (30 meters per pixel in this scene) imaging capacity of ETM+ with its multi-spectral capabilities allows scientists to penetrate the smoke plume and see the structure of the fire on the surface. Notice the high-level of detail in the infrared image (bottom), in which burn scars are clearly distinguished from the hotter smoldering and flaming parts of the fire. Within this image pair several features are clearly visible, including the Cerro Grande fire and smoke plume, the town of Los Alamos, the Los Alamos National Laboratory and associated property, and Cerro Grande peak. Combining ETM+ channels 7, 4, and 2 (one visible and two infrared channels) results in a false color image where vegetation appears as bright to dark green (bottom image). Forested areas are generally dark green while herbaceous vegetation is light green. Rangeland or more open areas appear pink to light purple. Areas with extensive pavement or urban development appear light blue or white to purple. Less densely-developed residential areas appear light green and golf courses are very bright green. The areas recently burned appear black. Dark red to bright red patches, or linear features within the burned area, are the hottest and possibly actively burning areas of the fire. The fire is spreading downslope and the front of the fire is readily detectable about 2 kilometers to the west and south of Los Alamos. Combining ETM+ channels 3, 2, and 1 provides a true-color image of the greater Los Alamos region (top image). Vegetation is generally dark to medium green. Forested areas are very dark green while herbaceous vegetation is medium green. Rangeland or more open areas appear as tan or light brown. Areas with extensive pavement or urban development appear white to light green. Less densely-developed residential areas appear medium green and golf courses are medium green. The fires and areas recently burned are obscured by smoke plumes which are white to light blue. Landsat 7 data are archived and available from EDC. Image by Rob Simmon, Earth Observatory, NASA Goddard Space Flight Center. Data courtesy Randy McKinley, EROS Data Center (EDC)
Design and Implement of Astronomical Cloud Computing Environment In China-VO
NASA Astrophysics Data System (ADS)
Li, Changhua; Cui, Chenzhou; Mi, Linying; He, Boliang; Fan, Dongwei; Li, Shanshan; Yang, Sisi; Xu, Yunfei; Han, Jun; Chen, Junyi; Zhang, Hailong; Yu, Ce; Xiao, Jian; Wang, Chuanjun; Cao, Zihuang; Fan, Yufeng; Liu, Liang; Chen, Xiao; Song, Wenming; Du, Kangyu
2017-06-01
Astronomy cloud computing environment is a cyber-Infrastructure for Astronomy Research initiated by Chinese Virtual Observatory (China-VO) under funding support from NDRC (National Development and Reform commission) and CAS (Chinese Academy of Sciences). Based on virtualization technology, astronomy cloud computing environment was designed and implemented by China-VO team. It consists of five distributed nodes across the mainland of China. Astronomer can get compuitng and storage resource in this cloud computing environment. Through this environments, astronomer can easily search and analyze astronomical data collected by different telescopes and data centers , and avoid the large scale dataset transportation.
An EMSO data case study within the INDIGO-DC project
NASA Astrophysics Data System (ADS)
Monna, Stephen; Marcucci, Nicola M.; Marinaro, Giuditta; Fiore, Sandro; D'Anca, Alessandro; Antonacci, Marica; Beranzoli, Laura; Favali, Paolo
2017-04-01
We present our experience based on a case study within the INDIGO-DataCloud (INtegrating Distributed data Infrastructures for Global ExplOitation) project (www.indigo-datacloud.eu). The aim of INDIGO-DC is to develop a data and computing platform targeting scientific communities. Our case study is an example of activities performed by INGV using data from seafloor observatories that are nodes of the infrastructure EMSO (European Multidisciplinary Seafloor and water column Observatory)-ERIC (www.emso-eu.org). EMSO is composed of several deep-seafloor and water column observatories, deployed at key sites in the European waters, thus forming a widely distributed pan-European infrastructure. In our case study we consider data collected by the NEMO-SN1 observatory, one of the EMSO nodes used for geohazard monitoring, located in the Western Ionian Sea in proximity of Etna volcano. Starting from the case study, through an agile approach, we defined some requirements for INDIGO developers, and tested some of the proposed INDIGO solutions that are of interest for our research community. Given that EMSO is a distributed infrastructure, we are interested in INDIGO solutions that allow access to distributed data storage. Access should be both user-oriented and machine-oriented, and with the use of a common identity and access system. For this purpose, we have been testing: - ONEDATA (https://onedata.org), as global data management system. - INDIGO-IAM as Identity and Access Management system. Another aspect we are interested in is the efficient data processing, and we have focused on two types of INDIGO products: - Ophidia (http://ophidia.cmcc.it), a big data analytics framework for eScience for the analysis of multidimensional data. - A collection of INDIGO Services to run processes for scientific computing through the INDIGO Orchestrator.
NASA Astrophysics Data System (ADS)
Wray, J. D.
2003-05-01
The robotic observatory telescope must point precisely on the target object, and then track autonomously to a fraction of the FWHM of the system PSF for durations of ten to twenty minutes or more. It must retain this precision while continuing to function at rates approaching thousands of observations per night for all its years of useful life. These stringent requirements raise new challenges unique to robotic telescope systems design. Critical design considerations are driven by the applicability of the above requirements to all systems of the robotic observatory, including telescope and instrument systems, telescope-dome enclosure systems, combined electrical and electronics systems, environmental (e.g. seeing) control systems and integrated computer control software systems. Traditional telescope design considerations include the effects of differential thermal strain, elastic flexure, plastic flexure and slack or backlash with respect to focal stability, optical alignment and angular pointing and tracking precision. Robotic observatory design must holistically encapsulate these traditional considerations within the overall objective of maximized long-term sustainable precision performance. This overall objective is accomplished through combining appropriate mechanical and dynamical system characteristics with a full-time real-time telescope mount model feedback computer control system. Important design considerations include: identifying and reducing quasi-zero-backlash; increasing size to increase precision; directly encoding axis shaft rotation; pointing and tracking operation via real-time feedback between precision mount model and axis mounted encoders; use of monolithic construction whenever appropriate for sustainable mechanical integrity; accelerating dome motion to eliminate repetitive shock; ducting internal telescope air to outside dome; and the principal design criteria: maximizing elastic repeatability while minimizing slack, plastic deformation and hysteresis to facilitate long-term repeatably precise pointing and tracking performance.
Gamma Ray Observatory (GRO) OBC attitude error analysis
NASA Technical Reports Server (NTRS)
Harman, R. R.
1990-01-01
This analysis involves an in-depth look into the onboard computer (OBC) attitude determination algorithm. A review of TRW error analysis and necessary ground simulations to understand the onboard attitude determination process are performed. In addition, a plan is generated for the in-flight calibration and validation of OBC computed attitudes. Pre-mission expected accuracies are summarized and sensitivity of onboard algorithms to sensor anomalies and filter tuning parameters are addressed.
ERIC Educational Resources Information Center
Eggensperger, Martin B.
2000-01-01
Introduces the Meteor Scatter Project (MSP) in which high school students build an automated meteor observatory and learn to monitor meteor activity. Involves students in activities such as radio frequency survey, antenna design, antenna construction, manual meteor counts, and computer board configuration and installation. (YDS)
Cyberinfrastructure (CI) for Interactive Ocean Observatories: LOOKING Ahead
NASA Astrophysics Data System (ADS)
Orcutt, J.; Abbott, M.; Bellingham, J.; Chave, A.; Delaney, J.; Johnson, R.; Lazowska, E.; Moline, M.; Smarr, L.
2004-12-01
Investments in next-generation facilities to achieve a permanent, interactive telepresence throughout remote or hostile environments can empower a broad spectrum of autonomous sensornet facilities through the NSF Major Research Equipment and Facililties Construction Ocean Observatories Initiative (OOI). These systems must involve powerful suites of generic cyberinfrastructure tools designed to optimize access and benefits to a large academic and public user base. Many future research and educational efforts focused throughout the ocean basins, especially within heavily populated coastal regions, will be empowered by these new systems. Our project LOOKING (Laboratory for the Ocean Observatory Knowledge Integration Grid) is developing prototype CI for the OOI to achieve these goals. In the case of ocean observatory networks, it is essential to establish powerful network infrastructures linking the wet or subsea portion, with a host of shore station facilities. These components in turn must seamlessly communicate with an ensemble of data repositories, and relevant computer and visualization resources designed to serve a widely diverse ocean science community with real time, broadband access to all observatory system data, products, and metadata. This infrastructure must be secure, reliable, and resilient. It must meet the potentially ambitious latency, bandwidth, and performance requirements demanded by a set of evolving autonomous sensor platforms over a period of decades. This Grid environment must seamlessly interconnect all relevant national and international research and education nets accessible through high speed, next generation communication networks. The primary components of LOOKING are remote services that fulfill the CI needs of the ocean observatory community. These services arise from overarching science and education requirements: 1) Instrument Services operate at the sensor end of an ocean observatory, and are dominantly but not exclusively wet. 2) Infrastructure Services operate within the ocean observatory itself, providing data, time distribution, and power functions to instruments; 3) Data Services interface the ocean observatory to users, whether human beings or modeling programs. In an appropriately designed and functioning system, none can stand alone, nor can they be developed in isolation. These services and associated middleware layers must be designed from the outset to interact seamlessly and transparently.
Metrology measurements for large-aperture VPH gratings
NASA Astrophysics Data System (ADS)
Zheng, Jessica R.; Gers, Luke; Heijmans, Jeroen
2013-09-01
The High Efficiency and Resolution Multi Element Spectrograph (HERMES) for the Australian Astronomical Observatory (AAO) uses four large aperture, high angle of incidence volume phase holographic gratings (VPHG) for high resolution `Galactic archaeology' spectroscopy. The large clear aperture, the high diffraction efficiency, the line frequency homogeneity, and mosaic alignment made manufacturing and testing challenging. We developed new metrology systems at the AAO to verify the performance of these VPH gratings. The measured diffraction efficiencies and line frequency of the VPH gratings received so far meet the vendor's provided data. The wavefront quality for the Blue VPH grating is good but the Green and Red VPH gratings need to be post polishing.
Semi-annual Sq-variation in solar activity cycle
NASA Astrophysics Data System (ADS)
Pogrebnoy, V.; Malosiev, T.
The peculiarities of semi-annual variation in solar activity cycle have been studied. The data from observatories having long observational series and located in different latitude zones were used. The following observatories were selected: Huancayo (magnetic equator), from 1922 to 1959; Apia (low latitudes), from 1912 to 1961; Moscow (middle latitudes), from 1947 to 1965. Based on the hourly values of H-components, the average monthly diurnal amplitudes (a difference between midday and midnight values), according to five international quiet days, were computed. Obtained results were compared with R (relative sunspot numbers) in the ranges of 0-30R, 40-100R, and 140-190R. It was shown, that the amplitude of semi-annual variation increases with R, from minimum to maximum values, on average by 45%. At equatorial Huancayo observatory, the semi-annual Sq(H)-variation appears especially clearly: its maximums take place at periods of equinoxes (March-April, September-October), and minimums -- at periods of solstices (June-July, December-January). At low (Apia observatory) and middle (Moscow observatory) latitudes, the character of semi-annual variation is somewhat different: it appears during the periods of equinoxes, but considerably less than at equator. Besides, with the growth of R, semi-annual variation appears against a background of annual variation, in the form of second peaks (maximum in June). At observatories located in low and middle latitudes, second peaks become more appreciable with an increase of R (March-April and September-October). During the periods of low solar activity, they are insignificant. This work has been carried out with the support from International Scientific and Technology Center (Project #KR-214).
Solaris: a global network of autonomous observatories in the southern hemisphere
NASA Astrophysics Data System (ADS)
Kozłowski, S. K.; Sybilski, P.; Konacki, Maciej; Pawłaszek, R. K.; Ratajczak, Milena; Helminiak, K. G.
2014-07-01
We present Project Solaris, a network of four autonomous observatories in the Southern Hemisphere. The Project's primary goal is to detect and characterize circumbinary planets using the eclipse timing approach. This method requires high-cadence and long time-span photometric coverage of the binaries' eclipses, hence the observatories are located at sites having similar separation in longitude and nearly identical latitudes: South African Astronómical Observatory, Republic of South Africa (Solaris-1 and -2), Siding Spring Observatory, Australia (Solaris-3) and Complejo Astronomico El Leoncito, Argentina (Solaris-4). The headquarters coordinating and monitoring the network is based in Toruń, Poland. All four sites are operational as of December 2013. The instrument and hardware configurations are nearly identical. Each site is equipped with a 0.5-m Ritchey-Chrétien or Schmidt-Cassegrain optical tube assembly mounted on a direct-drive modified German equatorial mount along with a set of instruments. Computer, power and networking components are installed in rack cabinets. Everything is housed in sandwiched fiberglass clamshell 3.5-m diameter robotized domes. The Argentinian site is additionally equipped with a 20-ft office container. We discuss the design requirements of robotic observatories aimed to operate autonomously as a global network with concentration on efficiency, robustness and modularity. We also present a newly introduced spectroscopic mode of operation commissioned on the Solaris-1 telescope. Using a compact échelle spectrograph (20 000 resolution) mounted directly on the imaging train of the telescope, we are able to remotely acquire spectra. A fully robotic spectroscopic mode is planned for 2015.
Michielsen, K.; De Raedt, H.; Stavenga, D. G.
2010-01-01
We present a comparison of the computer simulation data of gyroid nanostructures with optical measurements (reflectivity spectra and scattering diagrams) of ventral wing scales of the Green Hairstreak butterfly, Callophrys rubi. We demonstrate that the omnidirectional green colour arises from the gyroid cuticular structure grown in the domains of different orientation. We also show that this three-dimensional structure, operating as a biophotonic crystal, gives rise to various polarization effects. We briefly discuss the possible biological utility of the green coloration and polarization effects. PMID:19828506
Green's function calculations for semi-infinite carbon nanotubes
NASA Astrophysics Data System (ADS)
John, D. L.; Pulfrey, D. L.
2006-02-01
In the modeling of nanoscale electronic devices, the non-equilibrium Green's function technique is gaining increasing popularity. One complication in this method is the need for computation of the self-energy functions that account for the interactions between the active portion of a device and its leads. In the one-dimensional case, these functions may be computed analytically. In higher dimensions, a numerical approach is required. In this work, we generalize earlier methods that were developed for tight-binding Hamiltonians, and present results for the case of a carbon nanotube.
Relativistic central-field Green's functions for the RATIP package
NASA Astrophysics Data System (ADS)
Koval, Peter; Fritzsche, Stephan
2005-11-01
From perturbation theory, Green's functions are known for providing a simple and convenient access to the (complete) spectrum of atoms and ions. Having these functions available, they may help carry out perturbation expansions to any order beyond the first one. For most realistic potentials, however, the Green's functions need to be calculated numerically since an analytic form is known only for free electrons or for their motion in a pure Coulomb field. Therefore, in order to facilitate the use of Green's functions also for atoms and ions other than the hydrogen-like ions, here we provide an extension to the RATIP program which supports the computation of relativistic (one-electron) Green's functions in an—arbitrarily given—central-field potential V(r). Different computational modes have been implemented to define these effective potentials and to generate the radial Green's functions for all bound-state energies E<0. In addition, care has been taken to provide a user-friendly component of the RATIP package by utilizing features of the Fortran 90/95 standard such as data structures, allocatable arrays, or a module-oriented design. Program summaryTitle of program:XGREENS Catalogue number: ADWM Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADWM Program obtainable from: CPC Program Library, Queen's University of Belfast, N. Ireland Licensing provisions:None Computer for which the new version has been tested: PC Pentium II, III, IV, Athlon Installations: University of Kassel (Germany) Operating systems: SuSE Linux 8.2, SuSE Linux 9.0 Program language used in the new version: ANSI standard Fortran 90/95 Memory required to execute with typical data: On a standard grid (400 nodes), one central-field Green's function requires about 50 kBytes in RAM while approximately 3 MBytes are needed if saved as two-dimensional array on some external disc space No. of bits in a word: Real variables of double- and quad-precision are used Peripheral used: Disk for input/output CPU time required to execute test data: 2 min on a 450 MHz Pentium III processor No. of lines in distributed program, including test data etc.: 82 042 No. of bytes in distributed program, including test data etc.: 814 096 Distribution format: tar.gz Nature of the physical problem: In atomic perturbation theory, Green's functions may help carry out the summation over the complete spectrum of atom and ions, including the (summation over the) bound states as well as an integration over the continuum [R.A. Swainson, G.W.F. Drake, J. Phys. A 24 (1991) 95]. Analytically, however, these functions are known only for free electrons ( V(r)≡0) and for electrons in a pure Coulomb field ( V(r)=-Z/r). For all other choices of the potential, in contrast, the Green's functions must be determined numerically. Method of solution: Relativistic Green's functions are generated for an arbitrary central-field potential V(r)=-Z(r)/r by using a piecewise linear approximation of the effective nuclear charge function Z(r) on some grid r(i=1,…,N): Z(r)=Z0i+Z1ir. Then, following McGuire's algorithm [E.J. McGuire, Phys. Rev. A 23 (1981) 186], the radial Green's functions are constructed from the (two) linear-independent solutions of the homogeneous equation [P. Morse, H. Feshbach, Methods of Theoretical Physics, McGraw-Hill, New York 1953 (Part 1, p. 825)]. In the computation of these radial functions, the Kummer and Tricomi functions [J. Spanier, B. Keith, An Atlas of Functions, Springer, New York, 1987] are used extensively. Restrictions onto the complexity of the problem: The main restrictions of the program concern the shape of the effective nuclear charge Z(r)=-rV(r), i.e. the choice of the potential, and the allowed energies. Apart from obeying the proper boundary conditions for a point-like nucleus, namely, Z(r→0)=Z>0 and Z(r→∞)=Z-N⩾0, the first derivative of the charge function Z(r) must be smaller than the (absolute value of the) energy of the Green's function, {∂Z(r)}/{∂r}<|E|. Unusual features of the program:XGREENS has been designed as a part of the RATIP package [S. Fritzsche, J. Elec. Spec. Rel. Phen. 114-116 (2001) 1155] for the calculation of relativistic atomic transition and ionization properties. In a short dialog at the beginning of the execution, the user can specify the choice of the potential as well as the energies and the symmetries of the radial Green's functions to be calculated. Apart from central-field Green's functions, of course, the Coulomb Green's function [P. Koval, S. Fritzsche, Comput. Phys. Comm. 152 (2003) 191] can also be computed by selecting a constant nuclear charge Z(r)=Z. In order to test the generated Green's functions, moreover, we compare the two lowest bound-state orbitals which are calculated from the Green's functions with those as generated separately for the given potential. Like the other components of the RATIP package, XGREENS makes careful use of the Fortran 90/95 standard.
The U.S. NSF Ocean Observatories Initiative: A Modern Virtual Observatory
NASA Astrophysics Data System (ADS)
Orcutt, John; Vernon, Frank; Peach, Cheryl; Arrott, Matthew; Graybeal, John; Farcas, Claudiu; Farcas, Emilia; Krueger, Ingolf; Meisinger, Michael; Chave, Alan
2010-05-01
The NSF Ocean Observatories Initiative (OOI) began a five-year construction period in October 2009. The Consortium on Ocean Leadership (COL) manages the overall program with Implementing Organizations for Coastal/Global Scale Nodes (CGSN) at Woods Hole, Oregon State and Scripps; the Regional Cabled Network (RCN) at U of Washington and Cyberinfrastructure (CI) at UCSD and more than ten subcontractors. The NSF has made a commitment to support the observatory operations and maintenance for a 30-year period; a minimal period of time to measure physical, chemical and biological data over a length of time possibly sufficient to measure secular changes associated with climate and geodesy. The CI component is a substantial departure from previous approaches to data distribution and management. These innovations include the availability of data in near-real-time with latencies of seconds, open access to all data, analysis of the data stream for detection and modeling, use of the derived knowledge to modify the network with minimal or no human interaction and maintenance of data provenance through time as new versions of the data are created through QA/QC processes. The network architecture is designed to be scalable so that addition of new sensors is straightforward and inexpensive with costs increasing linearly at worst. Rather than building new computer infrastructure (disk farms and computer clusters), we are presently exploiting Amazon's Extensible Computing Cloud (EC2) and Simple Storage System (S3) to reduce long-term commitments to hardware and maintenance in order to minimize operations and maintenance costs. The OOI CI is actively partnering with other organizations (e.g. NOAA's IOOS) to integrate existing data systems using many of the same technologies to improve broad access to existing and planned observing systems, including those that provide critical climate data. Because seasonal and annual variability of most measureable parameters is so large, the measurement of small secular variations requires sensors with little or no drift over many annual cycles as well as absolute timing between globally distributed sensors that exceeds current practice by orders of magnitude.
Comprehension and retrieval of failure cases in airborne observatories
NASA Technical Reports Server (NTRS)
Alvarado, Sergio J.; Mock, Kenrick J.
1995-01-01
This paper describes research dealing with the computational problem of analyzing and repairing failures of electronic and mechanical systems of telescopes in NASA's airborne observatories, such as KAO (Kuiper Airborne Observatory) and SOFIA (Stratospheric Observatory for Infrared Astronomy). The research has resulted in the development of an experimental system that acquires knowledge of failure analysis from input text, and answers questions regarding failure detection and correction. The system's design builds upon previous work on text comprehension and question answering, including: knowledge representation for conceptual analysis of failure descriptions, strategies for mapping natural language into conceptual representations, case-based reasoning strategies for memory organization and indexing, and strategies for memory search and retrieval. These techniques have been combined into a model that accounts for: (a) how to build a knowledge base of system failures and repair procedures from descriptions that appear in telescope-operators' logbooks and FMEA (failure modes and effects analysis) manuals; and (b) how to use that knowledge base to search and retrieve answers to questions about causes and effects of failures, as well as diagnosis and repair procedures. This model has been implemented in FANSYS (Failure ANalysis SYStem), a prototype text comprehension and question answering program for failure analysis.
Graphics interfaces and numerical simulations: Mexican Virtual Solar Observatory
NASA Astrophysics Data System (ADS)
Hernández, L.; González, A.; Salas, G.; Santillán, A.
2007-08-01
Preliminary results associated to the computational development and creation of the Mexican Virtual Solar Observatory (MVSO) are presented. Basically, the MVSO prototype consists of two parts: the first, related to observations that have been made during the past ten years at the Solar Observation Station (EOS) and at the Carl Sagan Observatory (OCS) of the Universidad de Sonora in Mexico. The second part is associated to the creation and manipulation of a database produced by numerical simulations related to solar phenomena, we are using the MHD ZEUS-3D code. The development of this prototype was made using mysql, apache, java and VSO 1.2. based GNU and `open source philosophy'. A graphic user interface (GUI) was created in order to make web-based, remote numerical simulations. For this purpose, Mono was used, because it is provides the necessary software to develop and run .NET client and server applications on Linux. Although this project is still under development, we hope to have access, by means of this portal, to other virtual solar observatories and to be able to count on a database created through numerical simulations or, given the case, perform simulations associated to solar phenomena.
Comprehension and retrieval of failure cases in airborne observatories
NASA Astrophysics Data System (ADS)
Alvarado, Sergio J.; Mock, Kenrick J.
1995-05-01
This paper describes research dealing with the computational problem of analyzing and repairing failures of electronic and mechanical systems of telescopes in NASA's airborne observatories, such as KAO (Kuiper Airborne Observatory) and SOFIA (Stratospheric Observatory for Infrared Astronomy). The research has resulted in the development of an experimental system that acquires knowledge of failure analysis from input text, and answers questions regarding failure detection and correction. The system's design builds upon previous work on text comprehension and question answering, including: knowledge representation for conceptual analysis of failure descriptions, strategies for mapping natural language into conceptual representations, case-based reasoning strategies for memory organization and indexing, and strategies for memory search and retrieval. These techniques have been combined into a model that accounts for: (a) how to build a knowledge base of system failures and repair procedures from descriptions that appear in telescope-operators' logbooks and FMEA (failure modes and effects analysis) manuals; and (b) how to use that knowledge base to search and retrieve answers to questions about causes and effects of failures, as well as diagnosis and repair procedures. This model has been implemented in FANSYS (Failure ANalysis SYStem), a prototype text comprehension and question answering program for failure analysis.
The Pisgah Astronomical Research Institute
NASA Astrophysics Data System (ADS)
Cline, J. Donald; Castelaz, M.
2009-01-01
Pisgah Astronomical Research Institute is a not-for-profit foundation located at a former NASA tracking station in the Pisgah National Forest in western North Carolina. PARI is celebrating its 10th year. During its ten years, PARI has developed and implemented innovative science education programs. The science education programs are hands-on experimentally based, mixing disciplines in astronomy, computer science, earth and atmospheric science, engineering, and multimedia. The basic tools for the educational programs include a 4.6-m radio telescope accessible via the Internet, a StarLab planetarium, the Astronomical Photographic Data Archive (APDA), a distributed computing online environment to classify stars called SCOPE, and remotely accessible optical telescopes. The PARI 200 acre campus has a 4.6-m, a 12-m and two 26-m radio telescopes, optical solar telescopes, a Polaris monitoring telescope, 0.4-m and 0.35-m optical research telescopes, and earth and atmospheric science instruments. PARI is also the home of APDA, a repository for astronomical photographic plate collections which will eventually be digitized and made available online. PARI has collaborated with visiting scientists who have developed their research with PARI telescopes and lab facilities. Current experiments include: the Dedicated Interferometer for Rapid Variability (Dennison et al. 2007, Astronomical and Astrophysical Transactions, 26, 557); the Plate Boundary Observatory operated by UNAVCO; the Clemson University Fabry-Perot Interferometers (Meriwether 2008, Journal of Geophysical Research, submitted) measuring high velocity winds and temperatures in the Thermosphere, and the Western Carolina University - PARI variable star program. Current status of the education and research programs and instruments will be presented. Also, development plans will be reviewed. Development plans include the greening of PARI with the installation of solar panels to power the optical telescopes, a new distance learning center, and enhancements to the atmospheric and earth science suite of instrumentation.
Pulsar discovery by global volunteer computing.
Knispel, B; Allen, B; Cordes, J M; Deneva, J S; Anderson, D; Aulbert, C; Bhat, N D R; Bock, O; Bogdanov, S; Brazier, A; Camilo, F; Champion, D J; Chatterjee, S; Crawford, F; Demorest, P B; Fehrmann, H; Freire, P C C; Gonzalez, M E; Hammer, D; Hessels, J W T; Jenet, F A; Kasian, L; Kaspi, V M; Kramer, M; Lazarus, P; van Leeuwen, J; Lorimer, D R; Lyne, A G; Machenschalk, B; McLaughlin, M A; Messenger, C; Nice, D J; Papa, M A; Pletsch, H J; Prix, R; Ransom, S M; Siemens, X; Stairs, I H; Stappers, B W; Stovall, K; Venkataraman, A
2010-09-10
Einstein@Home aggregates the computer power of hundreds of thousands of volunteers from 192 countries to mine large data sets. It has now found a 40.8-hertz isolated pulsar in radio survey data from the Arecibo Observatory taken in February 2007. Additional timing observations indicate that this pulsar is likely a disrupted recycled pulsar. PSR J2007+2722's pulse profile is remarkably wide with emission over almost the entire spin period; the pulsar likely has closely aligned magnetic and spin axes. The massive computing power provided by volunteers should enable many more such discoveries.
Have Observatory, Will Travel.
ERIC Educational Resources Information Center
White, James C., II
1996-01-01
Describes several of the labs developed by Project CLEA (Contemporary Laboratory Experiences in Astronomy). The computer labs cover simulated spectrometer use, investigating the moons of Jupiter, radar measurements, energy flow out of the sun, classifying stellar spectra, photoelectric photometry, Doppler effect, eclipsing binary stars, and lunar…
AstroCloud, a Cyber-Infrastructure for Astronomy Research: Overview
NASA Astrophysics Data System (ADS)
Cui, C.; Yu, C.; Xiao, J.; He, B.; Li, C.; Fan, D.; Wang, C.; Hong, Z.; Li, S.; Mi, L.; Wan, W.; Cao, Z.; Wang, J.; Yin, S.; Fan, Y.; Wang, J.
2015-09-01
AstroCloud is a cyber-Infrastructure for Astronomy Research initiated by Chinese Virtual Observatory (China-VO) under funding support from NDRC (National Development and Reform commission) and CAS (Chinese Academy of Sciences). Tasks such as proposal submission, proposal peer-review, data archiving, data quality control, data release and open access, Cloud based data processing and analyzing, will be all supported on the platform. It will act as a full lifecycle management system for astronomical data and telescopes. Achievements from international Virtual Observatories and Cloud Computing are adopted heavily. In this paper, backgrounds of the project, key features of the system, and latest progresses are introduced.
Images of Kilauea East Rift Zone eruption, 1983-1993
Takahashi, Taeko Jane; Abston, C.C.; Heliker, C.C.
1995-01-01
This CD-ROM disc contains 475 scanned photographs from the U.S. Geological Survey Hawaii Observatory Library. The collection represents a comprehensive range of the best photographic images of volcanic phenomena for Kilauea's East Rift eruption, which continues as of September 1995. Captions of the images present information on location, geologic feature or process, and date. Short documentations of work by the USGS Hawaiian Volcano Observatory in geology, seismology, ground deformation, geophysics, and geochemistry are also included, along with selected references. The CD-ROM was produced in accordance with the ISO 9660 standard; however, it is intended for use only on DOS-based computer systems.
Science & Technology Review: September 2016
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vogt, Ramona L.; Meissner, Caryn N.; Chinn, Ken B.
2016-09-30
This is the September issue of the Lawrence Livermore National Laboratory's Science & Technology Review, which communicates, to a broad audience, the Laboratory’s scientific and technological accomplishments in fulfilling its primary missions. This month, there are features on "Laboratory Investments Drive Computational Advances" and "Laying the Groundwork for Extreme-Scale Computing." Research highlights include "Nuclear Data Moves into the 21st Century", "Peering into the Future of Lick Observatory", and "Facility Drives Hydrogen Vehicle Innovations."
The Argus+ Project: Wide-field, high-resolution 3mm molecular imaging with the Green Bank Telescope
NASA Astrophysics Data System (ADS)
Lockman, Felix J.
2018-06-01
Argus+ is a large format radio camera system for the Green Bank Telescope (GBT) that will carry out high-fidelity spectroscopic mapping in the molecule-rich 3mm band. The project builds on the success of the prototype 16-pixel Argus 3mm receiver. Argus+ will be nine copies of Argus in a single dewer, with lower noise amplifiers, for an increase of a factor of ten in mapping speed. The Argus+ project includes a dedicated spectrometer and improvements to the GBT metrology that will more than double the amount of useful observing time at 3mm. With a footprint of 6'x6’, 144 pixels, an angular resolution of 6″ to 8″, and the sensitivity of a filled aperture, Argus+ will map fundamental transitions of important species over hundreds of square arc-min with a spatial dynamic range of 104 to 105. The Argus+ project includes two legacy surveys: a survey of molecules in the Gould Belt molecular clouds, and a survey of dense gas in nearby galaxies. These will be carried out by the scientific community and will be defined through a series of workshops. The Project has a strong educational component and will involve undergraduates at every stage. It will be incorporated into new and existing outreach programs, and will produce materials for the Green Bank Science Center. Argus+ will be operated as an open skies facility of the Green Bank Observatory, with the majority of its use being allocated through the normal proposal review process.
NASA Technical Reports Server (NTRS)
Oh, K. S.; Schutt-Aine, J.
1995-01-01
Modeling of interconnects and associated discontinuities with the recent advances high-speed digital circuits has gained a considerable interest over the last decade although the theoretical bases for analyzing these structures were well-established as early as the 1960s. Ongoing research at the present time is focused on devising methods which can be applied to more general geometries than the ones considered in earlier days and, at the same time, improving the computational efficiency and accuracy of these methods. In this thesis, numerically efficient methods to compute the transmission line parameters of a multiconductor system and the equivalent capacitances of various strip discontinuities are presented based on the quasi-static approximation. The presented techniques are applicable to conductors embedded in an arbitrary number of dielectric layers with two possible locations of ground planes at the top and bottom of the dielectric layers. The cross-sections of conductors can be arbitrary as long as they can be described with polygons. An integral equation approach in conjunction with the collocation method is used in the presented methods. A closed-form Green's function is derived based on weighted real images thus avoiding nested infinite summations in the exact Green's function; therefore, this closed-form Green's function is numerically more efficient than the exact Green's function. All elements associated with the moment matrix are computed using the closed-form formulas. Various numerical examples are considered to verify the presented methods, and a comparison of the computed results with other published results showed good agreement.
Toothguide Trainer tests with color vision deficiency simulation monitor.
Borbély, Judit; Varsányi, Balázs; Fejérdy, Pál; Hermann, Péter; Jakstat, Holger A
2010-01-01
The aim of this study was to evaluate whether simulated severe red and green color vision deficiency (CVD) influenced color matching results and to investigate whether training with Toothguide Trainer (TT) computer program enabled better color matching results. A total of 31 color normal dental students participated in the study. Every participant had to pass the Ishihara Test. Participants with a red/green color vision deficiency were excluded. A lecture on tooth color matching was given, and individual training with TT was performed. To measure the individual tooth color matching results in normal and color deficient display modes, the TT final exam was displayed on a calibrated monitor that served as a hardware-based method of simulating protanopy and deuteranopy. Data from the TT final exams were collected in normal and in severe red and green CVD-simulating monitor display modes. Color difference values for each participant in each display mode were computed (∑ΔE(ab)(*)), and the respective means and standard deviations were calculated. The Student's t-test was used in statistical evaluation. Participants made larger ΔE(ab)(*) errors in severe color vision deficient display modes than in the normal monitor mode. TT tests showed significant (p<0.05) difference in the tooth color matching results of severe green color vision deficiency simulation mode compared to normal vision mode. Students' shade matching results were significantly better after training (p=0.009). Computer-simulated severe color vision deficiency mode resulted in significantly worse color matching quality compared to normal color vision mode. Toothguide Trainer computer program improved color matching results. Copyright © 2010 Elsevier Ltd. All rights reserved.
Radar Model of Asteroid 216 Kleopatra
NASA Technical Reports Server (NTRS)
2000-01-01
These images show several views from a radar-based computer model of asteroid 216 Kleopatra. The object, located in the main asteroid belt between Mars and Jupiter, is about 217 kilometers (135 miles) long and about 94 kilometers (58 miles) wide, or about the size of New Jersey.
This dog bone-shaped asteroid is an apparent leftover from an ancient, violent cosmic collision. Kleopatra is one of several dozen asteroids whose coloring suggests they contain metal.A team of astronomers observing Kleopatra used the 305-meter (1,000-foot) telescope of the Arecibo Observatory in Puerto Rico to bounce encoded radio signals off Kleopatra. Using sophisticated computer analysis techniques, they decoded the echoes, transformed them into images, and assembled a computer model of the asteroid's shape.The images were obtained when Kleopatra was about 171 million kilometers (106 million miles) from Earth. This model is accurate to within about 15 kilometers (9 miles).The Arecibo Observatory is part of the National Astronomy and Ionosphere Center, operated by Cornell University, Ithaca, N.Y., for the National Science Foundation. The Kleopatra radar observations were supported by NASA's Office of Space Science, Washington, DC. JPL is managed for NASA by the California Institute of Technology in Pasadena.Surface Green's function of a piezoelectric half-space.
Laude, Vincent; Jerez-Hanckes, Carlos F; Ballandras, Sylvain
2006-02-01
The computation of the two-dimensional harmonic spatial-domain Green's function at the surface of a piezoelectric half-space is discussed. Starting from the known form of the Green's function expressed in the spectral domain, the singular contributions are isolated and treated separately. It is found that the surface acoustic wave contributions (i.e., poles in the spectral Green's function) give rise to an anisotropic generalization of the Hankel function H0(2), the spatial Green's function for the scalar two-dimensional wave equation. The asymptotic behavior at infinity and at the origin (for the electrostatic contribution) also are explicitly treated. The remaining nonsingular part of the spectral Green's function is obtained numerically by a combination of fast Fourier transform and quadrature. Illustrations are given in the case of a substrate of Y-cut lithium niobate.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ewsuk, K.G.; Cochran, R.J.; Blackwell, B.F.
The properties and performance of a ceramic component is determined by a combination of the materials from which it was fabricated and how it was processed. Most ceramic components are manufactured by dry pressing a powder/binder system in which the organic binder provides formability and green compact strength. A key step in this manufacturing process is the removal of the binder from the powder compact after pressing. The organic binder is typically removed by a thermal decomposition process in which heating rate, temperature, and time are the key process parameters. Empirical approaches are generally used to design the burnout time-temperaturemore » cycle, often resulting in excessive processing times and energy usage, and higher overall manufacturing costs. Ideally, binder burnout should be completed as quickly as possible without damaging the compact, while using a minimum of energy. Process and computational modeling offer one means to achieve this end. The objective of this study is to develop an experimentally validated computer model that can be used to better understand, control, and optimize binder burnout from green ceramic compacts.« less
Yang, Yiqun; Urban, Matthew W; McGough, Robert J
2018-05-15
Shear wave calculations induced by an acoustic radiation force are very time-consuming on desktop computers, and high-performance graphics processing units (GPUs) achieve dramatic reductions in the computation time for these simulations. The acoustic radiation force is calculated using the fast near field method and the angular spectrum approach, and then the shear waves are calculated in parallel with Green's functions on a GPU. This combination enables rapid evaluation of shear waves for push beams with different spatial samplings and for apertures with different f/#. Relative to shear wave simulations that evaluate the same algorithm on an Intel i7 desktop computer, a high performance nVidia GPU reduces the time required for these calculations by a factor of 45 and 700 when applied to elastic and viscoelastic shear wave simulation models, respectively. These GPU-accelerated simulations also compared to measurements in different viscoelastic phantoms, and the results are similar. For parametric evaluations and for comparisons with measured shear wave data, shear wave simulations with the Green's function approach are ideally suited for high-performance GPUs.
Hawaiian Volcano Observatory seismic data, January to March 2009
Nakata, Jennifer S.; Okubo, Paul G.
2010-01-01
Figures 11–14 are maps showing computer-located hypocenters. The maps were generated using the Generic Mapping Tools (GMT), found at http://gmt.soest.hawaii.edu/ (last accessed 01/22/2010), in place of traditional QPLOT maps.
NASA Technical Reports Server (NTRS)
Alley, C. O.; Rayner, J. D.; Steggerda, C. A.; Mullendore, J. V.; Small, L.; Wagner, S.
1983-01-01
A horizontal two-way time comparison link in air between the University of Maryland laser ranging and time transfer equipment at the Goddard Optical Research Facility (GORF) 1.2 m telescope and the Time Services Division of the U.S. Naval Observatory (USNO) was established. Flat mirrors of 25 cm and 30 cm diameter respectively were placed on top of the Washington Cathedral and on a water tower at the Beltsville Agricultural Research Center. Two optical corner reflectors at the USNO reflect the laser pulses back to the GORF. Light pulses of 100 ps duration and an energy of several hundred microjoules are sent at the rate of 10 pulses per second. The detection at the USNO is by means of an RCA C30902E avalanche photodiode and the timing is accomplished by an HP 5370A computing counter and an HP 1000 computer with respect to a 10 pps pulse train from the Master Clock.
Performance of ground attitude determination procedures for HEAO-1
NASA Technical Reports Server (NTRS)
Fallon, L., III; Sturch, C. R.
1978-01-01
Ground attitude support for HEAO 1 provided at GSFC by the HEAO 1 Attitude Ground Support System (AGSS) is described. Information telemetered from Sun sensors, gyroscopes, star trackers, and an onboard computer are used by the AGSS to compute updates to the onboard attitude reference and gyro calibration parameters. The onboard computer utilizes these updates in providing continuous attitudes (accurate to 0.25degree) for use in the observatory's attitude control procedures. The relationship between HEAO 1 onboard and ground processing, the procedures used by the AGSS in computing attitude and gyro calibration updates, and the performance of these procedures in the HEAO 1 postlaunch environment is discussed.
Newly Commissioned Green Bank Telescope Bags New Pulsars
NASA Astrophysics Data System (ADS)
2002-01-01
Astronomers using the National Science Foundation's newly commissioned Robert C. Byrd Green Bank Telescope (GBT) have discovered a windfall of three previously undetected millisecond pulsars in a dense cluster of stars in the Milky Way Galaxy. The Green Bank Telescope The Robert C. Byrd Green Bank Telescope "This globular cluster, known as Messier 62, has been very well studied, and it would have been an exciting discovery to find just one new pulsar. The fact that we were able to detect three new pulsars at one time is simply remarkable," said Bryan Jacoby, a graduate student at the California Institute of Technology who led the research team. Results of the discovery were recently announced in an International Astronomical Union Circular. Jacoby and his colleague Adam Chandler, also a graduate student at Caltech, used the GBT to search for new pulsars in addition to the three already known in this cluster. Their research was part of the GBT's Early Science Program, which allows scientific investigations during the testing and commissioning of the telescope. The researchers used the Berkeley-Caltech Pulsar Machine, a new instrument whose development was overseen by Donald Backer at the University of California at Berkeley, to process the signals from the GBT and record them for later analysis. After their data were analyzed, the researchers discovered the telltale signatures of three additional pulsars and their white dwarf companion stars. Pulsars are rapidly rotating neutron stars that emit intense beams of radio waves along their misaligned magnetic axes. When these beams intersect the Earth, we see the pulsar flash on and off. Due to their exquisitely steady rotation, pulsars allow astronomers to study the basic laws of physics and the ways in which these dense clusters and exotic stellar systems are formed. Astronomers study globular clusters because they are among the oldest building blocks of our Galaxy. With their very dense stellar populations, these clusters are breeding grounds for unusual binary star systems, like the ones detected by the researchers. All three pulsars are known as "millisecond pulsars" because they make one complete rotation in only a few thousandths of a second. One of these newly discovered pulsars spins at approximately 440 rotations per second, and the other two both spin about 300 times per second. All are orbited by white dwarfs with orbital periods ranging from 4 to 27 hours. "This discovery demonstrates the remarkable sensitivity of the Green Bank Telescope," said Phil Jewell, site director for the National Radio Astronomy Observatory in Green Bank, W.Va. "The fact that these pulsars were never before detected in this highly studied area of the Galaxy shows that the GBT has outstanding capabilities and will be an important tool for astronomers to make very precise, very sensitive observations of the Universe. The GBT is the world's largest fully steerable radio telescope. It was dedicated on August 25, 2000, after nearly 10 years of construction. Since that time, engineers and scientists at the NRAO in Green Bank have been testing the telescope and outfitting it with the sensitive receivers and electronics that will make it one of the world's premier astronomical instruments. "As a graduate student," said Jacoby "this discovery was particularly satisfying, and I feel privileged to be part of the history of the Green Bank Telescope." Shrinivas Kulkarni, the Caltech faculty advisor for this project, remarked, "it is very satisfying to see such discoveries being made by young people. GBT is poised to play a significant role in the education of young astronomers." The National Radio Astronomy Observatory is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc.
Green's function solution to radiative heat transfer between longitudinal gray fins
NASA Technical Reports Server (NTRS)
Frankel, J. I.; Silvestri, J. J.
1991-01-01
A demonstration is presented of the applicability and versatility of a pure integral formulation for radiative-conductive heat-transfer problems. Preliminary results have been obtained which indicate that this formulation allows an accurate, fast, and stable computation procedure to be implemented. Attention is given to the accessory problem defining Green's function.
TimeSet: A computer program that accesses five atomic time services on two continents
NASA Technical Reports Server (NTRS)
Petrakis, P. L.
1993-01-01
TimeSet is a shareware program for accessing digital time services by telephone. At its initial release, it was capable of capturing time signals only from the U.S. Naval Observatory to set a computer's clock. Later the ability to synchronize with the National Institute of Standards and Technology was added. Now, in Version 7.10, TimeSet is able to access three additional telephone time services in Europe - in Sweden, Austria, and Italy - making a total of five official services addressable by the program. A companion program, TimeGen, allows yet another source of telephone time data strings for callers equipped with TimeSet version 7.10. TimeGen synthesizes UTC time data strings in the Naval Observatory's format from an accurately set and maintained DOS computer clock, and transmits them to callers. This allows an unlimited number of 'freelance' time generating stations to be created. Timesetting from TimeGen is made feasible by the advent of Becker's RighTime, a shareware program that learns the drift characteristics of a computer's clock and continuously applies a correction to keep it accurate, and also brings .01 second resolution to the DOS clock. With clock regulation by RighTime and periodic update calls by the TimeGen station to an official time source via TimeSet, TimeGen offers the same degree of accuracy within the resolution of the computer clock as any official atomic time source.
Takano, Kouji; Komatsu, Tomoaki; Hata, Naoki; Nakajima, Yasoichi; Kansaku, Kenji
2009-08-01
The white/gray flicker matrix has been used as a visual stimulus for the so-called P300 brain-computer interface (BCI), but the white/gray flash stimuli might induce discomfort. In this study, we investigated the effectiveness of green/blue flicker matrices as visual stimuli. Ten able-bodied, non-trained subjects performed Alphabet Spelling (Japanese Alphabet: Hiragana) using an 8 x 10 matrix with three types of intensification/rest flicker combinations (L, luminance; C, chromatic; LC, luminance and chromatic); both online and offline performances were evaluated. The accuracy rate under the online LC condition was 80.6%. Offline analysis showed that the LC condition was associated with significantly higher accuracy than was the L or C condition (Tukey-Kramer, p < 0.05). No significant difference was observed between L and C conditions. The LC condition, which used the green/blue flicker matrix was associated with better performances in the P300 BCI. The green/blue chromatic flicker matrix can be an efficient tool for practical BCI application.
NASA Astrophysics Data System (ADS)
Wang, Futong; Tao, Xiaxin; Xie, Lili; Raj, Siddharthan
2017-04-01
This study proposes a Green's function, an essential representation of water-saturated ground under moving excitation, to simulate ground borne vibration from trains. First, general solutions to the governing equations of poroelastic medium are derived by means of integral transform. Secondly, the transmission and reflection matrix approach is used to formulate the relationship between displacement and stress of the stratified ground, which results in the matrix of the Green's function. Then the Green's function is combined into a train-track-ground model, and is verified by typical examples and a field test. Additional simulations show that the computed ground vibration attenuates faster in the immediate vicinity of the track than in the surrounding area. The wavelength of wheel-rail unevenness has a notable effect on computed displacement and pore pressure. The variation of vibration intensity with the depth of ground is significantly influenced by the layering of the strata soil. When the train speed is equal to the velocity of the Rayleigh wave, the Mach cone appears in the simulated wave field. The proposed Green's function is an appropriate representation for a layered ground with shallow ground water table, and will be helpful to understand the dynamic responses of the ground to complicated moving excitation.
Multiple Etalon Systems for the Advanced Technology Solar Telescope
NASA Technical Reports Server (NTRS)
Gary, G. Allen; Balasubramaniam, K. S.; Sigwarth, Michael; Six, N. Frank (Technical Monitor)
2002-01-01
Multiple etalons systems are discussed that meet the 4-meter NSO/Advance Technology Solar Telescope (http://www.nso.edu/ATST/index.html) instrument and science requirements for a narrow bandpass imaging system. A multiple etalon system can provide an imaging interferometer working in four distinct modes: as a spectro-polarimeter, a filter-vector magnetograph, and a wide-band and broad-band high-resolution imager. Specific dual and triple etalon configurations will be described that provides spectrographic passband of 2.0-3.5nm and reduces parasitic light levels to 1/10000 as required by precise polarization measurement, e.g., Zeeman measurements of magnetic sensitive lines. A TESOS-like triple etalon system provides for spectral purity of 100 thousandths. The triple designs have the advantage of reducing the finesse requirement on each etalon, allowing much more stable blocking filters, and can have very high spectral purity. A dual-etalon double-pass Cavallini-like configuration can provide a competing configuration. This design can provide high contrast with only a double etalon. The selection of the final focal plan instrument will depend on a trade-off of the ideal instrument versus reality, the number of etalons, the aperture of etalons, the number of blocking filters the electronic control system and computer interfaces, the temperature control and controllers for the etalons and the electronics. The use of existing experience should provide significant cost savings. The heritage of use of etalons and multiple etalon systems in solar physics come from a number of observatories, which includes MSFC Solar Observatory (NASA), Sac Peak Observatory (NSO), and Kiepenheuer Institute for Solar Physics (Germany), Mees Solar Observatory (University of Hawaii), and Arcetri Astrophysical Observatory (Italy). The design of the ATST multiple etalon system will reply on the existing experience from these observatories.
NASA Astrophysics Data System (ADS)
Munch, F. D.; Grayver, A. V.; Kuvshinov, A.; Khan, A.
2018-01-01
In this paper we estimate and invert local electromagnetic (EM) sounding data for 1-D conductivity profiles in the presence of nonuniform oceans and continents to most rigorously account for the ocean induction effect that is known to strongly influence coastal observatories. We consider a new set of high-quality time series of geomagnetic observatory data, including hitherto unused data from island observatories installed over the last decade. The EM sounding data are inverted in the period range 3-85 days using stochastic optimization and model exploration techniques to provide estimates of model range and uncertainty. The inverted conductivity profiles are best constrained in the depth range 400-1,400 km and reveal significant lateral variations between 400 km and 1,000 km depth. To interpret the inverted conductivity anomalies in terms of water content and temperature, we combine laboratory-measured electrical conductivity of mantle minerals with phase equilibrium computations. Based on this procedure, relatively low temperatures (1200-1350°C) are observed in the transition zone (TZ) underneath stations located in Southern Australia, Southern Europe, Northern Africa, and North America. In contrast, higher temperatures (1400-1500°C) are inferred beneath observatories on islands, Northeast Asia, and central Australia. TZ water content beneath European and African stations is ˜0.05-0.1 wt %, whereas higher water contents (˜0.5-1 wt %) are inferred underneath North America, Asia, and Southern Australia. Comparison of the inverted water contents with laboratory-constrained water storage capacities suggests the presence of melt in or around the TZ underneath four geomagnetic observatories in North America and Northeast Asia.
V5588 SGR = Nova Sagittarii 2011 No. 2 = Pnv J18102135-2305306
NASA Astrophysics Data System (ADS)
Waagen, Elizabeth O.
2011-04-01
Announces the discovery of Nova Sgr 2011 No. 2 = V5588 SGR = PNV J18102135-2305306 by Koichi Nishiyama (Kurume, Japan) and Fujio Kabashima (Miyaki, Japan) on ~ 2011 March 27.832 UT at unfiltered CCD magnitude mag 11.7. Spectra obtained by A. Arai, M. Nagashima, T. Kajikawa, and C. Naka (Koyama Astronomical Observatory, Kyoto Sangyo University) on Mar. 28.725 UT suggest that the object is a classical nova reddened by interstellar matter. The object was designated PNV J18102135-2305306 when posted on the Central Bureau's Transient Objects Confirmation Page (TOCP) webpage. E. Kazarovets, on behalf of the GCVS team, reports that the name V5588 Sgr has been assigned to this nova. It was nitially announced in CBET 2679 (Daniel W. E. Green, ed.) and AAVSO Special Notice #237 (Waagen). Additional information published in IAU Circular 9203 (Green, ed.). Finder charts with sequence may be created using the AAVSO Variable Star Plotter (http://www.aavso.org/vsp). Observations should be submitted to the AAVSO International Database. See full Alert Notice for more details and observations.
The Order of the Dolphin: Origins of SETI
NASA Astrophysics Data System (ADS)
Temming, Maria; Crider, Anthony
2016-01-01
In 1961, the National Academy of Sciences organized a meeting on the search for extraterrestrial intelligence (SETI) at the National Radio Astronomy Observatory in Green Bank, West Virginia. The ten scientists who attended, including future SETI icons such as Frank Drake and Carl Sagan, represented a variety of scientific fields. At the conclusion of the meeting, the attendees adopted the moniker "The Order of the Dolphin," in honor of participant John Lilly's work on interspecies communication. Since this seminal meeting, researchers in each of the attendees' fields have contributed in some way to the search for intelligent life. This study investigates the circumstances that led to each attendee's invitation to Green Bank and explores SETI as the legacy of this meeting. We will focus in this talk on the SETI connections of two attendees, astronomer Otto Struve and physicist Philip Morrison, both in regards to their personal contributions to SETI and the influence of their work on subsequent SETI research. Specifically, we will examine proposals by Otto Struve for exoplanet discovery methods, and Philip Morrison for radio searches that laid the groundwork for modern SETI.
Argus+: The Future of Wide-Field, Spectral-Line Imaging at 3-mm with the Green Bank Telescope
NASA Astrophysics Data System (ADS)
Maddalena, Ronald; Frayer, David; Lockman, Felix; O'Neil, Karen; White, Steven; Argus+ Collaboration
2018-01-01
The Robert C Byrd Green Bank Telescope has met its design goal of providing high-quality observations at 115 GHz. Observers also have access to the new, 16-pixel, 3-mm Argus receiver, which is providing high-dynamic range images over wide fields for the multitude of spectral lines between 85 and 115 GHz, including CO, 13CO, C18O, SiO, HCN, HCO+, HNC, N2H+, and CS. The small number of pixels in Argus limits its ability to map many of the most interesting objects whose extent exceeds many arc-minutes. The successful performance of Argus, and its modular design, demonstrates that receivers with many more pixels could be built for the GBT. A 12 x 12 array of the Argus design would have mapping speeds about nine times faster than Argus without suffering any degradation in performance for the outer pixels in the array. We present our plans to build the next-generation Argus instrument (Argus+) with 144-pixels, a footprint 5’x5’, and 7" resolution at 110 GHz. The project will be a collaboration between the Green Bank Observatory and university groups, who will supply key components. The key science drivers for Argus+ are studies of molecular filaments in the Milky Way, studies of molecular clouds in nearby galaxies, and the observations of rapidly evolving solar system objects.
A Remotely Operated Observatory for Minor Planet Photometry
NASA Astrophysics Data System (ADS)
Ditteon, Richard
2008-05-01
In October of 2007 Rose-Hulman Institute of Technology in Terre Haute, Indiana began operating the Oakley Southern Sky Observatory (E09) located near Siding Spring Observatory in New South Wales, Australia. The observatory houses a 0.5-m, f/8.4 Ritchey-Chretien telescope mounted on a Paramount ME, German equatorial mount. Attached to the telescope is an STL-1001E CCD camera which has 1024 by 1024, 24 µm pixels, a two-stage thermoelectric cooler, and built in color filter wheel with BVRI and clear filters. Image scale is 1.2 arcseconds per pixel. A cloud sensor is used to monitor sky conditions. The observatory has a roll-off roof with limit switches to detect when the roof is fully open and fully closed. In addition, a switch has been added to the mount to detect when the telescope is parked and that it is safe to open or close the roof. All of the hardware is controlled by a custom program which reads a simple text file containing the sequence of images and targets to be collected each night. The text file is loaded onto the control computer once each day, then the software waits until sunset to determine if the sky is clear. When conditions are favorable, power is turned on, the roof opens, twilight flats, dark and bias frames are recorded, and when it is fully dark data frames are recorded. Images are transferred via the Internet back to Rose-Hulman by another program running in the background. The observatory closes itself before dawn or if it gets cloudy. Currently we are using the observatory for photometry of minor planets. Students are responsible for selecting targets, processing the returned images, determining the period and light curve of each minor planet and writing a paper for publication. Recent results will be presented.
Progress on the Low Frequency All Sky Monitor
NASA Astrophysics Data System (ADS)
Ford, Anthony; Jenet, F.; Craig, J.; Creighton, T. D.; Dartez, L. P.; Hicks, B.; Hinojosa, J.; Jaramillo, R.; Kassim, N. E.; Lunsford, G.; Miller, R. B.; Murray, J.; Ray, P. S.; Rivera, J.; Taylor, G. B.
2013-01-01
The Low Frequency All Sky Monitor is a system of geographically separated radio arrays dedicated to the study of radio transients. LoFASM consists of four stations, each comprised of 12 cross-dipole antennas designed to operate between 5-88MHz. The antennas and front end electronics for LoFASM were designed by the Naval Research Laboratory for the Long Wavelength Array project. Over the last year, undergraduate students from the University of Texas at Brownsville’s Center for Advanced Radio Astronomy have been establishing these stations around the continental US, consisting of sites located in Port Mansfield, Texas, the LWA North Arm site of the LWA1 Radio Observatory in New Mexico, adjacent to the North Arm of the Very Large Array, the Green Bank Radio Observatory, West Virginia, and NASA’s Goldstone tracking complex in California. In combination with the establishment of these sites was the development of the analog hardware, which consists of commercial off-the-shelf RF splitter/combiners and a custom amplifier and filter chain designed by colleagues at the University of New Mexico. This poster will expound on progress in site installation and development of the analog signal chain.
Chandra X-Ray Observatory Image of the Distant Galaxy, 3C294
NASA Technical Reports Server (NTRS)
2000-01-01
This most distant x-ray cluster of galaxies yet has been found by astronomers using Chandra X-ray Observatory (CXO). Approximately 10 billion light-years from Earth, the cluster 3C294 is 40 percent farther than the next most distant x-ray galaxy cluster. The existence of such a faraway cluster is important for understanding how the universe evolved. CXO's image reveals an hourglass-shaped region of x-ray emissions centered on the previously known central radio source (seen in this image as the blue central object) that extends outward for 60,000 light- years. The vast clouds of hot gas that surround such galaxies in clusters are thought to be heated by collapse toward the center of the cluster. Until CXO, x-ray telescopes have not had the needed sensitivity to identify such distant clusters of galaxies. Galaxy clusters are the largest gravitationally bound structures in the universe. The intensity of the x-rays in this CXO image of 3C294 is shown as red for low energy x-rays, green for intermediate, and blue for the most energetic x-rays. (Photo credit: NASA/loA/A. Fabian et al)
VizieR Online Data Catalog: Water maser emission toward post-AGB and PN (Gomez+, 2015)
NASA Astrophysics Data System (ADS)
Gomez, J. F.; Rizzo, J. R.; Suarez, O.; Palau, A.; Miranda, L. F.; Guerrero, M. A.; Ramos-Larios, G.; Torrelles, J. M.
2015-09-01
The observed sources are listed in Table 1. They comprise most of the sources in Ramos-Larios et al. (2009A&A...501.1207R). They are post-AGB stars and PN candidates with the IRAS color criteria of Suarez et al. (2006A&A...458..173S) and with signs of strong optical obscuration. We have also included some optically visible post-AGB stars from Suarez et al. (2006A&A...458..173S) that were not included in our previous water maser observations of Suarez et al. (2007A&A...467.1085S, 2009A&A...505..217S) or for which those observations had poor sensitivity. We observed the 616-523 transition of H2O (rest frequency = 22235.08MHz) using three different telescopes: the DSS-63 antenna (70m diameter) at the Madrid Deep Space Communications Complex (MDSCC) near Robledo de Chavela (Spain), the 64m antenna at the Parkes Observatory of the Australia Telescope National Facility (ATNF), and the 100m Robert C. Byrd Green Bank Telescope (GBT) of the National Radio Astronomy Observatory. The observed positions, rms noise per spectral channel, and observing dates are listed in Table 1. (3 data files).
The SERENDIP piggyback SETI project
NASA Technical Reports Server (NTRS)
Lampton, M.; Bowyer, S.; Werthimer, D.; Donnelly, C.; Herrick, W.
1992-01-01
The SERENDIP project is an ongoing program of monitoring and processing broadband radio signals acquired by existing radio astronomy observatories. SERENDIP operates in a piggyback mode: it makes use of whatever observing plan (sequence of frequencies, sky coordinates, and polarizations) is under way at its host observatory. Moreover, the SERENDIP data acquisition system, once installed, operates autonomously. This approach makes it possible to obtain large amounts of high quality observing time in a manner that is economical and that does not adversely affect ongoing radio astronomy survey work. The SERENDIP II system has been installed at the NRAO 300-foot telescope at Green Bank, West Virginia, and has operated there for several thousand hours. In this report, we summarize our findings from these observations and describe the present status of the project. Two key elements of SERENDIP are the automated data acquisition system that uses adaptive thresholds and logs only statistically significant peaks in the real-time power spectra, and the subsequent off-line analysis programs that identify and reject a variety of interference signals. Several specific correlations have been identified that offer promise. At present, the development and testing of these interference rejection algorithms is the main thrust of our work.
The SERENDIP piggyback SETI project.
Lampton, M; Bowyer, S; Werthimer, D; Donnelly, C; Herrick, W
1992-01-01
The SERENDIP project is an ongoing program of monitoring and processing broadband radio signals acquired by existing radio astronomy observatories. SERENDIP operates in a piggyback mode: it makes use of whatever observing plan (sequence of frequencies, sky coordinates, and polarizations) is under way at its host observatory. Moreover, the SERENDIP data acquisition system, once installed, operates autonomously. This approach makes it possible to obtain large amounts of high quality observing time in a manner that is economical and that does not adversely affect ongoing radio astronomy survey work. The SERENDIP II system has been installed at the NRAO 300-foot telescope at Green Bank, West Virginia, and has operated there for several thousand hours. In this report, we summarize our findings from these observations and describe the present status of the project. Two key elements of SERENDIP are the automated data acquisition system that uses adaptive thresholds and logs only statistically significant peaks in the real-time power spectra, and the subsequent off-line analysis programs that identify and reject a variety of interference signals. Several specific correlations have been identified that offer promise. At present, the development and testing of these interference rejection algorithms is the main thrust of our work.
NASA Technical Reports Server (NTRS)
1991-01-01
This photograph shows the Compton Gamma-Ray Observatory being released from the Remote Manipulator System (RMS) arm aboard the Space Shuttle Atlantis during the STS-35 mission in April 1991. The GRO reentered the Earth's atmosphere and ended its successful mission in June 2000. For nearly 9 years, GRO's Burst and Transient Source Experiment (BATSE), designed and built by the Marshall Space Flight Center, kept an unblinking watch on the universe to alert scientist to the invisible, mysterious gamma-ray bursts that had puzzled them for decades. By studying gamma-rays from objects like black holes, pulsars, quasars, neutron stars, and other exotic objects, scientists could discover clues to the birth, evolution, and death of star, galaxies, and the universe. The gamma-ray instrument was one of four major science instruments aboard the Compton. It consisted of eight detectors, or modules, located at each corner of the rectangular satellite to simultaneously scan the entire universe for bursts of gamma-rays ranging in duration from fractions of a second to minutes. In January 1999, the instrument, via the Internet, cued a computer-controlled telescope at Las Alamos National Laboratory in Los Alamos, New Mexico, within 20 seconds of registering a burst. With this capability, the gamma-ray experiment came to serve as a gamma-ray burst alert for the Hubble Space Telescope, the Chandra X-Ray Observatory, and major gound-based observatories around the world. Thirty-seven universities, observatories, and NASA centers in 19 states, and 11 more institutions in Europe and Russia, participated in BATSE's science program.
NASA Marshall Space Flight Center solar observatory report, January - June 1991
NASA Technical Reports Server (NTRS)
Smith, James E.
1991-01-01
Given here is a summary of the solar vector magnetic field, H-alpha, and white-light observations made at the NASA/Marshall Space Flight Center (MSFC) Solar Observatory during its daily periods of operation. The MSFC Solar Observatory facilities consist of the Solar Magnetograph, an f/13, 30-cm Cassegrain system with a 3.5-cm image of the Sun, housed on top of a 12.8-meter tower; a 12.5-cm Razdow H-alpha telescope housed at the base of the tower; an 18-cm Questar telescope with a full aperture white-light filter mounted at the base of the tower; a 30-cm Cassegrain telescope located in a second metal dome; and a 16.5-cm H-alpha telescope mounted on side of the Solar Vector Magnetograph. A concrete block building provides office space, a darkroom for developing film and performing optical testing, a workshop, video displays, and a computer facility for data reduction.
NASA Marshall Space Flight Center Solar Observatory report, July - December 1991
NASA Technical Reports Server (NTRS)
Smith, James E.
1992-01-01
A summary is given of the solar vector magnetic field, H-alpha, and white light observations made at the NASA/Marshall Space Flight Center (MSFC) Solar Observatory during its daily periods of observation. The MSFC Solar Observatory facilities consist of the Solar Magnetograph, an f-13, 30 cm Cassegrain system with a 3.5 cm image of the Sun housed on top of a 12.8 meter tower, a 12.5 cm Razdow H-alpha telescope housed at the base of the tower, an 18 cm Questar telescope with a full aperture white-light filter mounted at the base of the tower, a 30 cm Cassegrain telescope located in a second metal dome, and a 16.5 cm H-alpha telescope mounted on the side of the Solar Vector Magnetograph. A concrete block building provides office space, a darkroom for developing film and performing optical testing, a workshop, video displays, and a computer facility for data reduction.
Computer version of astronomical ephemerides.
NASA Astrophysics Data System (ADS)
Choliy, V. Ya.
A computer version of astronomical ephemerides for bodies of the Solar System, stars, and astronomical phenomena was created at the Main Astronomical Observatory of the National Academy of Sciences of Ukraine and the Astronomy and Cosmic Physics Department of the Taras Shevchenko National University. The ephemerides will be distributed via INTERNET or in the file form. This information is accessible via the web servers space.ups.kiev.ua and alfven.ups.kiev.ua or the address choliy@astrophys.ups.kiev.ua.
Astronomers Make First Images With Space Radio Telescope
NASA Astrophysics Data System (ADS)
1997-07-01
Marking an important new milestone in radio astronomy history, scientists at the National Radio Astronomy Observatory (NRAO) in Socorro, New Mexico, have made the first images using a radio telescope antenna in space. The images, more than a million times more detailed than those produced by the human eye, used the new Japanese HALCA satellite, working in conjunction with the National Science Foundation's (NSF) Very Long Baseline Array (VLBA) and Very Large Array (VLA) ground-based radio telescopes. The landmark images are the result of a long-term NRAO effort supported by the National Aeronautics and Space Administration (NASA). "This success means that our ability to make detailed radio images of objects in the universe is no longer limited by the size of the Earth," said NRAO Director Paul Vanden Bout. "Astronomy's vision has just become much sharper." HALCA, launched on Feb. 11 by Japan's Institute of Space and Astronautical Science (ISAS), is the first satellite designed for radio astronomy imaging. It is part of an international collaboration led by ISAS and backed by NRAO; Japan's National Astronomical Observatory; NASA's Jet Propulsion Laboratory (JPL); the Canadian Space Agency; the Australia Telescope National Facility; the European VLBI Network and the Joint Institute for Very Long Baseline Interferometry in Europe. On May 22, HALCA observed a distant active galaxy called PKS 1519-273, while the VLBA and VLA also observed it. Data from the satellite was received by a tracking station at the NRAO facility in Green Bank, West Virginia. Tape-recorded data from the satellite and from the radio telescopes on the ground were sent to NRAO's Array Operations Center (AOC) in Socorro, NM. In Socorro, astronomers and computer scientists used a special-purpose computer to digitally combine the signals from the satellite and the ground telescopes to make them all work together as a single, giant radio telescope. This dedicated machine, the VLBA Correlator, built as part of the VLBA instrument, was modified over the past four years to allow it to incorporate data from the satellite. Correlation of the observational data was completed successfully on June 12, after the exact timing of the satellite recording was established. Further computer processing produced an image of PKS 1519-273 -- the first image ever produced using a radio telescope in space. For Jim Ulvestad, the NRAO astronomer who made the first image, the success ended a long quest for this new capability. Ulvestad was involved in an experiment more than a decade ago in which a NASA communications satellite, TDRSS, was used to test the idea of doing radio astronomical imaging by combining data from space and ground radio telescopes. That experiment showed that an orbiting antenna could, in fact, work in conjunction with ground-based radio observatories, and paved the way for HALCA and a planned Russian radio astronomy satellite called RadioAstron. "This first image is an important technical milestone, and demonstrates the feasibility of a much more advanced mission, ARISE, currently being considered by NASA," Ulvestad said. The first image showed no structure in the object, even at the extremely fine level of detail achievable with HALCA; it is what astronomers call a "point source." This object also appears as a point source in all-ground-based observations. In addition, the 1986 TDRSS experiment observed the object, and, while this experiment did not produce an image, it indicated that PKS 1519-273 should be a point source. "This simple point image may not appear very impressive, but its beauty to us is that it shows our entire, complex system is functioning correctly. The system includes not only the orbiting and ground-based antennas, but also the orbit determination, tracking stations, the correlator, and the image-processing software," said Jonathan Romney, the NRAO astronomer who led the development of the VLBA correlator, and its enhancement to process data from orbiting radio telescopes. "We would be skeptical of a complex image if we had not been able to obtain a good point image first," Romney added. A second observing target, the quasar 1156+295, observed on June 5, made a more interesting picture. Seen by ground-based radio observatories, this object, at a distance of 6.5 billion light years, has been known to show an elongation in its structure to the northeast of the core. However, seen with the space-ground system, it is clearly shown to have both a core and a complex "jet" emerging from the core. Such jets, consisting of subatomic particles moving near the speed of light, are seen in many quasars and active galaxies throughout the universe. In fact, 1156+295 is one of a class of objects recently found by NASA's Compton Gamma-Ray Observatory to exhibit powerful gamma-ray emission; such objects are among the most compact and energetic known in the universe. "By showing that this object actually is a core-jet system, HALCA has produced its first new scientific information, and demonstrates its imaging capabilities for a variety of astrophysical investigations," Romney said. "This image shows that the jet extends much closer to the core, or 'central engine' of the quasar than is shown by ground-only imaging," Romney added. "This is an exciting and historical achievement for radio astronomy," said Miller Goss, NRAO's VLA/VLBA Director. "At NRAO, we have seen our colleagues -- scientists, electrical engineers, computer programmers and technicians in Socorro and Green Bank -- work for years on this project. Now, they can take pride in their success." Radio astronomers, like astronomers using visible light, usually seek to make images of the objects at which they aim their telescopes. Because radio waves are much longer than light waves, a radio telescope must be much larger than an optical instrument in order to see the same amount of detail. Greater ability to see detail, called resolving power, has been a quest of radio astronomers for more than half a century. To see a level of detail equal to that revealed by optical telescopes would require a radio-telescope dish miles across. In the 1950s, British and Australian scientists developed a technique that used smaller, widely-separated antennas, and combined their signals to produce resolving power equal to that of a single dish as large as the distance between the smaller dishes. This technique, called interferometry, is used by the VLA, with 27 antennas and a maximum separation of 20 miles, and the VLBA, with 10 antennas and a maximum separation of 5,000 miles. Systems such as the VLBA, in which the antennas are so widely separated that data must be individually tape-recorded at each site and combined after the observation, are called Very Long Baseline Interferometry (VLBI) systems. VLBI was developed by American and Canadian astronomers and was first successfully demonstrated in 1967. The VLBA, working with radio telescopes in Europe, represents the largest radio telescope that can be accommodated on the surface of the Earth. With an orbit that carries it more than 13,000 miles above the Earth, HALCA, working with the ground-based telescopes, extends the "sharp vision" of radio astronomy farther than ever before. Using HALCA, radio astronomers expect to routinely produce images with more than 100 times the detail seen by the Hubble Space Telescope. Astronomers around the world are waiting to use the satellite to seek answers to questions about some of the most distant and intriging objects in the universe. As much as one-third of the VLBA's observing time will be devoted to observations in conjunction with HALCA. Over the expected five-year lifetime of HALCA, scientists hope to observe hundreds of quasars, pulsars, galaxies, and other objects. Launched from Japan's Kagoshima Space Center, HALCA orbits the Earth every six hours, ranging from 350 to 13,200 miles high. The 1,830-pound satellite has a dish antenna 26 feet in diameter. The antenna, folded like an umbrella for the launch, was unfolded under radio control from the ground on Feb. 26. The antenna was pointed toward PKS 1519-273 after a three-month checkout of the spacecraft's electronics, computers and guidance systems. HALCA observations represent a true international scientific collaboration. In addition to the HALCA spacecraft, built, launched, and operated by Japan's ISAS, the participation of a large number of ground-based radio telescopes is also essential. NRAO's VLBA and VLA instruments, including the VLBA correlator, will be a vital component of this collaboration. Other radio telescopes in the U.S., Japan, Europe, and Australia, also will participate. NRAO's facility at Green Bank, WV, is one of five tracking stations where the data collected on the spacecraft are received and recorded. Another is at an ISAS facility in Japan, and JPL operates three additional tracking stations, in California, Australia, and Spain. JPL also collects information from all tracking stations to determine the very accurate spacecraft orbit necessary to reduce these observations. The NRAO Space VLBI efforts in Socorro and Green Bank were supported by funding from the National Aeronautics and Space Administration. The National Radio Astronomy Observatory is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc.
NASA Astrophysics Data System (ADS)
Marshall, Sean E.; Howell, Ellen S.; Brozović, Marina; Taylor, Patrick A.; Campbell, Donald B.; Benner, Lance A. M.; Naidu, Shantanu P.; Giorgini, Jon D.; Jao, Joseph S.; Lee, Clement G.; Richardson, James E.; Rodriguez-Ford, Linda A.; Rivera-Valentin, Edgard G.; Ghigo, Frank; Kobelski, Adam; Busch, Michael W.; Pravec, Petr; Warner, Brian D.; Reddy, Vishnu; Hicks, Michael D.; Crowell, Jenna L.; Fernandez, Yanga R.; Vervack, Ronald J.; Nolan, Michael C.; Magri, Christopher; Sharkey, Benjamin; Bozek, Brandon
2015-11-01
We report observations of potentially hazardous asteroid (85989) 1999 JD6, which passed 0.048 AU from Earth (19 lunar distances) during its close approach on July 25, 2015. During eleven days between July 15 and August 4, 2015, we observed 1999 JD6 with the Goldstone Solar System Radar and with Arecibo Observatory's planetary radar, including bistatic reception of some Goldstone echoes at Green Bank. We obtained delay-Doppler radar images at a wide range of latitudes, with range resolutions varying from 7.5 to 150 meters per pixel, depending on the observing conditions. We acquired near-infrared spectra from the NASA InfraRed Telescope Facility (IRTF) on two nights in July 2015, at wavelengths from 0.75 to 5.0 microns, showing JD6's thermal emission. We also obtained optical lightcurves from Ondrejov Observatory (in 1999), Table Mountain Observatory (in 2000), and Palmer Divide Station (in 2015). Previous observers had suggested that 1999 JD6 was most likely an elongated object, based on its large lightcurve amplitude of 1.2 magnitudes (Szabo et al. 2001; Polishook and Brosch 2008; Warner 2014). The radar images reveal an elongated peanut-shaped object, with two lobes separated by a sharp concavity. JD6's maximum diameter is about two kilometers, and its larger lobe is approximately 50% longer than its smaller lobe. The larger lobe has a concavity on its end. We will present more details on the shape and rotation state of 1999 JD6, as well as its surface properties from optical and infrared data and thermal modeling.
Volcanic Plumes Tower over Mount Etna
2013-11-06
Twin volcanic plumes—one of ash, one of gas—rose from Sicily’ Mount Etna on the morning of October 26, 2013. L’Istituto Nazionale di Geofisica e Vulcanologia (INGV) Osservatorio Etneo (National Institute of Geophysics and Volcanology Etna Observatory) reported that Etna was experiencing its first paroxysm in six months. Multiple eruption columns are common at Etna, a result of complex plumbing within the volcano. The Northeast Crater, one of several on Etna’s summit, was emitting the ash column, while the New Southeast Crater was simultaneously venting mostly gas. This natural-color image collected by Landsat 8 shows the view from space at 11:38 a.m. local time. The towering, gas-rich plume cast a dark shadow over the lower, ash-rich plume and Etna’s northwestern flank. Relatively fresh lava flows (less than a century or so old) are dark gray; vegetation is green; and the tile-roofed buildings of Bronte and Biancavilla lend the towns an ochre hue. NASA Earth Observatory image by Jesse Allen and Robert Simmon, using Landsat data from the USGS Earth Explorer. Photograph ©2013, Boris Behncke. Caption by Robert Simmon with contributions from Boris Behncke. Instrument: Landsat 8 - OLI More info: 1.usa.gov/1cEcOFi Credit: NASA Earth Observatory NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram
Volcanic Plumes Tower over Mount Etna [annotated
2013-11-06
Twin volcanic plumes—one of ash, one of gas—rose from Sicily’ Mount Etna on the morning of October 26, 2013. L’Istituto Nazionale di Geofisica e Vulcanologia (INGV) Osservatorio Etneo (National Institute of Geophysics and Volcanology Etna Observatory) reported that Etna was experiencing its first paroxysm in six months. Multiple eruption columns are common at Etna, a result of complex plumbing within the volcano. The Northeast Crater, one of several on Etna’s summit, was emitting the ash column, while the New Southeast Crater was simultaneously venting mostly gas. This natural-color image collected by Landsat 8 shows the view from space at 11:38 a.m. local time. The towering, gas-rich plume cast a dark shadow over the lower, ash-rich plume and Etna’s northwestern flank. Relatively fresh lava flows (less than a century or so old) are dark gray; vegetation is green; and the tile-roofed buildings of Bronte and Biancavilla lend the towns an ochre hue. NASA Earth Observatory image by Jesse Allen and Robert Simmon, using Landsat data from the USGS Earth Explorer. Photograph ©2013, Boris Behncke. Caption by Robert Simmon with contributions from Boris Behncke. Instrument: Landsat 8 - OLI More info: 1.usa.gov/1cEcOFi Credit: NASA Earth Observatory NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram
NASA Astrophysics Data System (ADS)
Chen, Yajie; Tian, Hui; Su, Yingna; Qu, Zhongquan; Deng, Linhua; Jibben, Patricia R.; Yang, Zihao; Zhang, Jingwen; Samanta, Tanmoy; He, Jiansen; Wang, Linghua; Zhu, Yingjie; Zhong, Yue; Liang, Yu
2018-03-01
We present an investigation of a coronal cavity observed above the western limb in the coronal red line Fe X 6374 Å using a telescope of Peking University and in the green line Fe XIV 5303 Å using a telescope of Yunnan Observatories, Chinese Academy of Sciences, during the total solar eclipse on 2017 August 21. A series of magnetic field models is constructed based on the magnetograms taken by the Helioseismic and Magnetic Imager on board the Solar Dynamics Observatory (SDO) one week before the eclipse. The model field lines are then compared with coronal structures seen in images taken by the Atmospheric Imaging Assembly on board SDO and in our coronal red line images. The best-fit model consists of a flux rope with a twist angle of 3.1π, which is consistent with the most probable value of the total twist angle of interplanetary flux ropes observed at 1 au. Linear polarization of the Fe XIII 10747 Å line calculated from this model shows a “lagomorphic” signature that is also observed by the Coronal Multichannel Polarimeter of the High Altitude Observatory. We also find a ring-shaped structure in the line-of-sight velocity of Fe XIII 10747 Å, which implies hot plasma flows along a helical magnetic field structure, in the cavity. These results suggest that the magnetic structure of the cavity is a highly twisted flux rope, which may erupt eventually. The temperature structure of the cavity has also been investigated using the intensity ratio of Fe XIII 10747 Å and Fe X 6374 Å.
Mauna Loa Volcano: Historical eruptions, exploration, and observations (1779-1910)
NASA Astrophysics Data System (ADS)
Barnard, Walther M.
The period 1779-1910 spans the years from the first Western contact with the Island of Hawaii through the decade immediately preceding the establishment of the Hawaiian Volcano Observatory and the beginning of systematic scientific investigation of Hawaii's volcanoes. During this period Mauna Loa apparently erupted a minimum of 30 times. Many of those eruptions were visited and described by non-scientists, foremost among whom was the Reverend Titus Coon. Some highlights in the exploration of Mauna Loa include the first recorded attempt to ascend the summit, in 1779, by John Ledyard; the first recorded successful ascent, in 1794, by Archibald Menzies; the ascent in 1834 by David Douglas, whose "incredible" description provoked considerable controversy; the topographic mapping of the summit area by the U. S. Exploring Expedition under Charles Wilkes in 1840-41 and the first ascents by women in 1873. Among the many contributions made to the emerging science of volcanology were Coan's recognition of lava tubes as conduits of lava, and his recognition of the processes of formation of tumuli and lateral outbreaks of lava; Dana's precepts on a variety of topics relating to Hawaiian volcanism; W. D. Alexander's and Haskell's descriptions of pahoehoe and aa lava, and early accounts of flow morphology and structure; Dutton's recognition that the calderas of Kilauea and Mauna Loa resulted from collapse; Green's description of formation of pillow lavas; and Guppy's suggestion and justification for the establishment of an observatory that subsequently led to the founding of the Hawaiian Volcano Observatory. Many contributed insights to the continuing debate on the relationship between Mauna Loa and Kilauea.
Operation of a P300-based brain-computer interface by individuals with cervical spinal cord injury.
Ikegami, Shiro; Takano, Kouji; Saeki, Naokatsu; Kansaku, Kenji
2011-05-01
This study evaluates the efficacy of a P300-based brain-computer interface (BCI) with green/blue flicker matrices for individuals with cervical spinal cord injury (SCI). Ten individuals with cervical SCI (age 26-53, all male) and 10 age- and sex-matched able-bodied controls (age 27-52, all male) with no prior BCI experience were asked to input hiragana (Japanese alphabet) characters using the P300 BCI with two distinct types of visual stimuli, white/gray and green/blue, in an 8×10 flicker matrix. Both online and offline performance were evaluated. The mean online accuracy of the SCI subjects was 88.0% for the white/gray and 90.7% for the green/blue flicker matrices. The accuracy of the control subjects was 77.3% and 86.0% for the white/gray and green/blue, respectively. There was a significant difference in online accuracy between the two types of flicker matrix. SCI subjects performed with greater accuracy than controls, but the main effect was not significant. Individuals with cervical SCI successfully controlled the P300 BCI, and the green/blue flicker matrices were associated with significantly higher accuracy than the white/gray matrices. The P300 BCI with the green/blue flicker matrices is effective for use not only in able-bodied subjects, but also in individuals with cervical SCI. Copyright © 2010 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.
The use of conduction model in laser weld profile computation
NASA Astrophysics Data System (ADS)
Grabas, Bogusław
2007-02-01
Profiles of joints resulting from deep penetration laser beam welding of a flat workpiece of carbon steel were computed. A semi-analytical conduction model solved with Green's function method was used in computations. In the model, the moving heat source was attenuated exponentially in accordance with Beer-Lambert law. Computational results were compared with those in the experiment.
NASA Astrophysics Data System (ADS)
Bachche, Shivaji; Oka, Koichi
2013-06-01
This paper presents the comparative study of various color space models to determine the suitable color space model for detection of green sweet peppers. The images were captured by using CCD cameras and infrared cameras and processed by using Halcon image processing software. The LED ring around the camera neck was used as an artificial lighting to enhance the feature parameters. For color images, CieLab, YIQ, YUV, HSI and HSV whereas for infrared images, grayscale color space models were selected for image processing. In case of color images, HSV color space model was found more significant with high percentage of green sweet pepper detection followed by HSI color space model as both provides information in terms of hue/lightness/chroma or hue/lightness/saturation which are often more relevant to discriminate the fruit from image at specific threshold value. The overlapped fruits or fruits covered by leaves can be detected in better way by using HSV color space model as the reflection feature from fruits had higher histogram than reflection feature from leaves. The IR 80 optical filter failed to distinguish fruits from images as filter blocks useful information on features. Computation of 3D coordinates of recognized green sweet peppers was also conducted in which Halcon image processing software provides location and orientation of the fruits accurately. The depth accuracy of Z axis was examined in which 500 to 600 mm distance between cameras and fruits was found significant to compute the depth distance precisely when distance between two cameras maintained to 100 mm.
Demonstration Of A Green-blue Approach For A Strategic Management Of Urban Runoff.
NASA Astrophysics Data System (ADS)
Jonczyk, J. C.; Quinn, P. F.; Heidrich, O.; James, P.; Harris, N.; Dawson, R. J.; Pearson, D. J.
2016-12-01
With more than half of the world's population now living in cities, there is an increasing need to facilitate urban areas to be more sustainable and resilient to the impacts of extreme events such as surface water flooding. Traditionally, urban storm water is managed predominately through grey infrastructure such as sewer collection systems and flood walls, often with little consideration of the increased water utility costs or downstream flood risk. There is little collaboration between organisations and sectors on managing and mitigating the impacts of flooding at city level, with decisions made in silos. A 24-acre development zone is used as a case study to show how different sectors and organisations came to realise the multiple benefits of a blue-green, joined-up, site-wide approach to managing storm runoff. The Science Central development zone (http://www.newcastlesciencecentral.com/) is at the heart of the city and is jointly owned by Newcastle University and the Newcastle city council with an overall vision for innovation and urban sustainability. The masterplan was reviewed and agreed by the partners in 2016 to include a site-wide holistic conveyance of surface water through a series of measures across the site, and the commercial needs of the building plots were balanced with the need to manage the flood hazard. Uniquely, once constructed, the measures will be monitored to evaluate how they function and the multiple benefits they provide will also be evaluated. This will include monitoring water and air quality parameters, indicators of biodiversity and carbon capture through The Urban Observatory. The Urban Observatory (http://urbanobservatory.ac.uk/) is a research project based at Newcastle University that produces a data portal of open and scalable data from deployments of heterogeneous sensors and 3rd party data sources around the city. The site will also host a new national sustainable urban drainage research facility that will provide research infrastructure to carry out detailed experiments, with the aim of improving the evidence based for green-blue solutions. Science Central and its approach to surface runoff is to be an exemplar of a future, sustainable city with a vision to demonstrate that making space for water can provide a more liveable and thriving environment for all.
Digital control of the Kuiper Airborne Observatory telescope
NASA Technical Reports Server (NTRS)
Mccormack, Ann C.; Snyder, Philip K.
1989-01-01
The feasibility of using a digital controller to stabilize a telescope mounted in an airplane is investigated. The telescope is a 30 in. infrared telescope mounted aboard a NASA C-141 aircraft known as the Kuiper Airborne Observatory. Current efforts to refurbish the 14-year-old compensation system have led to considering a digital controller. A typical digital controller is modeled and added into the telescope system model. This model is simulated on a computer to generate the Bode plots and time responses which determine system stability and performance parameters. Important aspects of digital control system hardware are discussed. A summary of the findings shows that a digital control system would result in satisfactory telescope performance.
NASA Technical Reports Server (NTRS)
1974-01-01
The specifications and functions of the Central Data Processing (CDPF) Facility which supports the Earth Observatory Satellite (EOS) are discussed. The CDPF will receive the EOS sensor data and spacecraft data through the Spaceflight Tracking and Data Network (STDN) and the Operations Control Center (OCC). The CDPF will process the data and produce high density digital tapes, computer compatible tapes, film and paper print images, and other data products. The specific aspects of data inputs and data processing are identified. A block diagram of the CDPF to show the data flow and interfaces of the subsystems is provided.
NASA Astrophysics Data System (ADS)
Shostak, Seth
The Drake equation, a commonly-used starting point for discussions about the likelihood of finding extraterrestrial intelligence, is now nearly a halfcentury old. It dates from 1961, a year after Frank Drake made his pioneering radio search for artificial signals from other worlds. That search, dubbed Project Ozma, was a 200-hour scrutiny of two nearby, Sun-like stars for transmissions spectrally situated near the 1420 MHz line of neutral hydrogen, and was conducted with an 85-foot antenna at the National Radio Astronomy Observatory in Green Bank, West Virginia (Drake, 1960; Kellermann and Seielstad, 1986). These efforts to find easy evidence of intelligence in other star systems provoked considerable public interest, including a major article in Saturday Review (Lear, 1960).
Go Green, Save Green with ENERGY STAR[R
ERIC Educational Resources Information Center
Hatcher, Caterina
2010-01-01
Did you know that the nation's 17,450 K-12 school districts spend more on energy than on computers and textbooks combined? Energy costs represent a typical school district's second largest operating expense after salaries. Schools that have earned the ENERGY STAR--EPA's mark of superior energy performance--cost 40 cents per square foot less to…
Isolation of the ocular surface to treat dysfunctional tear syndrome associated with computer use.
Yee, Richard W; Sperling, Harry G; Kattek, Ashballa; Paukert, Martin T; Dawson, Kevin; Garcia, Marcie; Hilsenbeck, Susan
2007-10-01
Dysfunctional tear syndrome (DTS) associated with computer use is characterized by mild irritation, itching, redness, and intermittent tearing after extended staring. It frequently involves foreign body or sandy sensation, blurring of vision, and fatigue, worsening especially at the end of the day. We undertook a study to determine the effectiveness of periocular isolation using microenvironment glasses (MEGS) alone and in combination with artificial tears in alleviating the symptoms and signs of dry eye related to computer use. At the same time, we evaluated the relative ability of a battery of clinical tests for dry eye to distinguish dry eyes from normal eyes in heavy computer users. Forty adult subjects who used computers 3 hours or more per day were divided into dry eye sufferers and controls based on their scores on the Ocular Surface Disease Index (OSDI). Baseline scores were recorded and ocular surface assessments were made. On four subsequent visits, the subjects played a computer game for 30 minutes in a controlled environment, during which one of four treatment conditions were applied, in random order, to each subject: 1) no treatment, 2) artificial tears, 3) MEGS, and 4) artificial tears combined with MEGS. Immediately after each session, subjects were tested on: a subjective comfort questionnaire, tear breakup time (TBUT), fluorescein staining, lissamine green staining, and conjunctival injection. In this study, a significant correlation was found between cumulative lifetime computer use and ocular surface disorder, as measured by the standardized OSDI index. The experimental and control subjects were significantly different (P<0.05) in the meibomian gland assessment and TBUT; they were consistently different in fluorescein and lissamine green staining, but with P>0.05. Isolation of the ocular surface alone produced significant improvements in comfort scores and TBUT and a consistent trend of improvement in fluorescein staining and lissamine green staining. Isolation plus tears produced a significant improvement in lissamine green staining. The subjective comfort inventory and the TBUT test were most effective in distinguishing between the treatments used. Computer users with ocular surface complaints should have a detailed ocular surface examination and, if symptomatic, they can be effectively treated with isolation of the ocular surface, artificial tears therapy, and effective environmental manipulations.
Reexamination of the coronal index of solar activity
NASA Astrophysics Data System (ADS)
Rybanský, M.; Rušin, V.; Minarovjech, M.; Klocok, L.; Cliver, E. W.
2005-08-01
The coronal index (CI) of solar activity is the irradiance of the Sun as a star in the coronal green line (Fe XIV, 530.3 nm or 5303 Å). It is derived from ground-based observations of the green corona made by the network of coronal stations (currently Kislovodsk, Lomnický Štít, Norikura, and Sacramento Peak). The CI was introduced by Rybanský (1975) to facilitate comparison of ground-based green line measurements with satellite-based extreme ultraviolet and soft X-ray observations. The CI since 1965 is based on the Lomnický Štít photometric scale; the CI was extended to earlier years by Rybanský et al. (1994) based on cross-calibrations of Lomnický Štít data with measurements made at Pic du Midi and Arosa. The resultant 1939-1992 CI had the interesting property that its value at the peak of the 11-year cycle increased more or less monotonically from cycle 18 through cycle 22 even though the peak sunspot number of cycle 20 exhibited a significant local minimum between that of cycles 19 and 21. Rušin and Rybanský (2002) recently showed that the green line intensity and photospheric magnetic field strength were highly correlated from 1976 to 1999. Since the photospheric magnetic field strength is highly correlated with sunspot number, the lack of close correspondence between the sunspot number and the CI from 1939 to 2002 is puzzling. Here we show that the CI and sunspot number are highly correlated only after 1965, calling the previously-computed coronal index for earlier years (1939-1965) into question. We can use the correlation between the CI and sunspot number (also the 2800 MHz radio flux and the cosmic ray intensity) to recompute daily values of the CI for years before 1966. In fact, this method can be used to obtain CI values as far back as we have reliable sunspot observations (˜1850). The net result of this exercise is a CI that closely tracks the sunspot number at all times. We can use the sunspot-CI relationship (for 1966-2002) to identify which coronal stations can be used as a basis for the homogeneous coronal data set (HDS) before 1966. Thus we adopt the photometric scale of the following observatories for the indicated times: Norikura (1951-1954; the Norikura photometric scale was also used from 1939 to 1954); Pic du Midi (1955-1959); Kislovodsk (1960-1965). Finally, we revised the post-1965 HDS and made several small corrections and now include data from Kislovodsk, Norikura, and Sacramento Peak to fill gaps at Lomnický Štít.
A new numerical algorithm for the analytic continuation of Green`s functions
DOE Office of Scientific and Technical Information (OSTI.GOV)
Natoli, V.D.; Cohen, M.H.; Fornberg, B.
1996-06-01
The need to calculate the spectral properties of a Hermitian operation H frequently arises in the technical sciences. A common approach to its solution involves the construction of the Green`s function operator G(z) = [z - H]{sup -1} in the complex z plane. For example, the energy spectrum and other physical properties of condensed matter systems can often be elegantly and naturally expressed in terms of the Kohn-Sham Green`s functions. However, the nonanalyticity of resolvents on the real axis makes them difficult to compute and manipulate. The Herglotz property of a Green`s function allows one to calculate it along anmore » arc with a small but finite imaginary part, i.e., G(x + iy), and then to continue it to the real axis to determine quantities of physical interest. In the past, finite-difference techniques have been used for this continuation. We present here a fundamentally new algorithm based on the fast Fourier transform which is both simpler and more effective. 14 refs., 9 figs.« less
Multiyear Interactive Computer Almanac (MICA)
from the U.S. Naval Observatory About MICA Features System Requirements Delta T File and Software Requirements | Delta T and Software Updates | FAQ and Bug Reports | Ordering ] Features MICA can perform the , and delta T). Twilight, rise, set, and transit times for major solar system bodies, selected bright
The coude spectrograph and echelle scanner of the 2.7 m telescope at McDonald Observatory.
NASA Technical Reports Server (NTRS)
Tull, R. G.
1972-01-01
Discussion of certain design aspects of the coude spectrograph, and description of the coude scanner that uses some of the spectrograph optics. The configuration of the large echelle grating used is reviewed along with the systems of computer scanner control and data handling.
The Coude spectrograph and echelle scanner of the 2.7 m telescope at McDonald observatory
NASA Technical Reports Server (NTRS)
Tull, R. G.
1972-01-01
The design of the Coude spectrograph of the 2.7 m McDonald telescope is discussed. A description is given of the Coude scanner which uses the spectrograph optics, the configuration of the large echelle and the computer scanner control and data systems.
Project PARAS: Phased array radio astronomy from space
NASA Technical Reports Server (NTRS)
Nuss, Kenneth; Hoffmann, Christopher; Dungan, Michael; Madden, Michael; Bendakhlia, Monia
1992-01-01
An orbiting radio telescope is proposed which, when operated in a very long baseline interferometry (VLBI) scheme, would allow higher than currently available angular resolution and dynamic range in the maps and the ability to observe rapidly changing astronomical sources. Using passive phased array technology, the proposed design consists of 656 hexagonal modules forming a 150-m diameter antenna dish. Each observatory module is largely autonomous, having its own photovoltaic power supply and low-noise receiver and processor for phase shifting. The signals received by the modules are channeled via fiber optics to the central control computer in the central bus module. After processing and multiplexing, the data are transmitted to telemetry stations on the ground. The truss frame supporting each observatory panel is a novel hybrid structure consisting of a bottom graphite/epoxy tubular triangle and rigidized inflatable Kevlar tubes connecting the top observatory panel and the bottom triangle. Attitude control and station keeping functions will be performed by a system of momentum wheels in the bus and four propulsion modules located at the compass points on the periphery of the observatory dish. Each propulsion module has four monopropellant thrusters and four hydrazine arcjets, the latter supported by either a photovoltaic array or a radioisotope thermoelectric generator. The total mass of the spacecraft is about 20,500 kg.
PARAS program: Phased array radio astronomy from space
NASA Astrophysics Data System (ADS)
Jakubowski, Antoni K.; Haynes, David A.; Nuss, Ken; Hoffmann, Chris; Madden, Michael; Dungan, Michael
1992-06-01
An orbiting radio telescope is proposed which, when operated in a Very Long Baseline Interferometry (VLBLI) scheme, would allow higher (than currently available) angular resolution and dynamic range in the maps, and the ability of observing rapidly changing astronomical sources. Using a passive phases array technology, the proposed design consists of 656 hexagonal modules forming a 150 meter diameter dish. Each observatory module is largely autonomous, having its own photovoltaic power supply and low-noise receiver and processor for phase shifting. The signals received by the modules are channeled via fiber optics to the central control computer in the central bus module. After processing and multiplexing, the data is transmitted to telemetry stations on the ground. The truss frame supporting each observatory pane is a hybrid structure consisting of a bottom graphite/epoxy tubular triangle and rigidized inflatable Kevlar tubes connecting the top observatory panel and bottom triangle. Attitude control and stationkeeping functions are performed by a system of momentum wheels in the bus and four propulsion modules located at the compass points on the periphery of the observatory dish. Each propulsion module has four monopropellant thrusters and six hydrazine arcjets, the latter supported by a nuclear reactor. The total mass of the spacecraft is 22,060 kg.
PARAS program: Phased array radio astronomy from space
NASA Technical Reports Server (NTRS)
Jakubowski, Antoni K.; Haynes, David A.; Nuss, Ken; Hoffmann, Chris; Madden, Michael; Dungan, Michael
1992-01-01
An orbiting radio telescope is proposed which, when operated in a Very Long Baseline Interferometry (VLBLI) scheme, would allow higher (than currently available) angular resolution and dynamic range in the maps, and the ability of observing rapidly changing astronomical sources. Using a passive phases array technology, the proposed design consists of 656 hexagonal modules forming a 150 meter diameter dish. Each observatory module is largely autonomous, having its own photovoltaic power supply and low-noise receiver and processor for phase shifting. The signals received by the modules are channeled via fiber optics to the central control computer in the central bus module. After processing and multiplexing, the data is transmitted to telemetry stations on the ground. The truss frame supporting each observatory pane is a hybrid structure consisting of a bottom graphite/epoxy tubular triangle and rigidized inflatable Kevlar tubes connecting the top observatory panel and bottom triangle. Attitude control and stationkeeping functions are performed by a system of momentum wheels in the bus and four propulsion modules located at the compass points on the periphery of the observatory dish. Each propulsion module has four monopropellant thrusters and six hydrazine arcjets, the latter supported by a nuclear reactor. The total mass of the spacecraft is 22,060 kg.
NASA Astrophysics Data System (ADS)
Simutė, S.; Fichtner, A.
2015-12-01
We present a feasibility study for seismic source inversions using a 3-D velocity model for the Japanese Islands. The approach involves numerically calculating 3-D Green's tensors, which is made efficient by exploiting Green's reciprocity. The rationale for 3-D seismic source inversion has several aspects. For structurally complex regions, such as the Japan area, it is necessary to account for 3-D Earth heterogeneities to prevent unknown structure polluting source solutions. In addition, earthquake source characterisation can serve as a means to delineate existing faults. Source parameters obtained for more realistic Earth models can then facilitate improvements in seismic tomography and early warning systems, which are particularly important for seismically active areas, such as Japan. We have created a database of numerically computed 3-D Green's reciprocals for a 40°× 40°× 600 km size area around the Japanese Archipelago for >150 broadband stations. For this we used a regional 3-D velocity model, recently obtained from full waveform inversion. The model includes attenuation and radial anisotropy and explains seismic waveform data for periods between 10 - 80 s generally well. The aim is to perform source inversions using the database of 3-D Green's tensors. As preliminary steps, we present initial concepts to address issues that are at the basis of our approach. We first investigate to which extent Green's reciprocity works in a discrete domain. Considering substantial amounts of computed Green's tensors we address storage requirements and file formatting. We discuss the importance of the initial source model, as an intelligent choice can substantially reduce the search volume. Possibilities to perform a Bayesian inversion and ways to move to finite source inversion are also explored.
Big Computing in Astronomy: Perspectives and Challenges
NASA Astrophysics Data System (ADS)
Pankratius, Victor
2014-06-01
Hardware progress in recent years has led to astronomical instruments gathering large volumes of data. In radio astronomy for instance, the current generation of antenna arrays produces data at Tbits per second, and forthcoming instruments will expand these rates much further. As instruments are increasingly becoming software-based, astronomers will get more exposed to computer science. This talk therefore outlines key challenges that arise at the intersection of computer science and astronomy and presents perspectives on how both communities can collaborate to overcome these challenges.Major problems are emerging due to increases in data rates that are much larger than in storage and transmission capacity, as well as humans being cognitively overwhelmed when attempting to opportunistically scan through Big Data. As a consequence, the generation of scientific insight will become more dependent on automation and algorithmic instrument control. Intelligent data reduction will have to be considered across the entire acquisition pipeline. In this context, the presentation will outline the enabling role of machine learning and parallel computing.BioVictor Pankratius is a computer scientist who joined MIT Haystack Observatory following his passion for astronomy. He is currently leading efforts to advance astronomy through cutting-edge computer science and parallel computing. Victor is also involved in projects such as ALMA Phasing to enhance the ALMA Observatory with Very-Long Baseline Interferometry capabilities, the Event Horizon Telescope, as well as in the Radio Array of Portable Interferometric Detectors (RAPID) to create an analysis environment using parallel computing in the cloud. He has an extensive track record of research in parallel multicore systems and software engineering, with contributions to auto-tuning, debugging, and empirical experiments studying programmers. Victor has worked with major industry partners such as Intel, Sun Labs, and Oracle. He holds a distinguished doctorate and a Habilitation degree in Computer Science from the University of Karlsruhe. Contact him at pankrat@mit.edu, victorpankratius.com, or Twitter @vpankratius.
Potential toxicity and affinity of triphenylmethane dye malachite green to lysozyme.
Ding, Fei; Li, Xiu-Nan; Diao, Jian-Xiong; Sun, Ye; Zhang, Li; Ma, Lin; Yang, Xin-Ling; Zhang, Li; Sun, Ying
2012-04-01
Malachite green is a triphenylmethane dye that is used extensively in many industrial and aquacultural processes, generating environmental concerns and health problems to human being. In this contribution, the complexation between lysozyme and malachite green was verified by means of computer-aided molecular modeling, steady state and time-resolved fluorescence, and circular dichroism (CD) approaches. The precise binding patch of malachite green in lysozyme has been identified from molecular modeling and ANS displacement, Trp-62, Trp-63, and Trp-108 residues of lysozyme were earmarked to possess high-affinity for this dye, the principal forces in the lysozyme-malachite green adduct are hydrophobic and π-π interactions. Steady state fluorescence proclaimed the complex of malachite green with lysozyme yields quenching through static type, which substantiates time-resolved fluorescence measurements that lysozyme-malachite green conjugation formation has an affinity of 10(3)M(-1). Moreover, via molecular modeling and also CD data, we can safely arrive at a conclusion that the polypeptide chain of lysozyme partially destabilized upon complexation with malachite green. The data emerged here will help to further understand the toxicological action of malachite green in human body. Copyright © 2012 Elsevier Inc. All rights reserved.
Ambient seismic noise interferometry in Hawai'i reveals long-range observability of volcanic tremor
Ballmer, Silke; Wolfe, Cecily; Okubo, Paul G.; Haney, Matt; Thurber, Clifford H.
2013-01-01
The use of seismic noise interferometry to retrieve Green's functions and the analysis of volcanic tremor are both useful in studying volcano dynamics. Whereas seismic noise interferometry allows long-range extraction of interpretable signals from a relatively weak noise wavefield, the characterization of volcanic tremor often requires a dense seismic array close to the source. We here show that standard processing of seismic noise interferometry yields volcanic tremor signals observable over large distances exceeding 50 km. Our study comprises 2.5 yr of data from the U.S. Geological Survey Hawaiian Volcano Observatory short period seismic network. Examining more than 700 station pairs, we find anomalous and temporally coherent signals that obscure the Green's functions. The time windows and frequency bands of these anomalous signals correspond well with the characteristics of previously studied volcanic tremor sources at Pu'u 'Ō'ō and Halema'uma'u craters. We use the derived noise cross-correlation functions to perform a grid-search for source location, confirming that these signals are surface waves originating from the known tremor sources. A grid-search with only distant stations verifies that useful tremor signals can indeed be recovered far from the source. Our results suggest that the specific data processing in seismic noise interferometry—typically used for Green's function retrieval—can aid in the study of both the wavefield and source location of volcanic tremor over large distances. In view of using the derived Green's functions to image heterogeneity and study temporal velocity changes at volcanic regions, however, our results illustrate how care should be taken when contamination by tremor may be present.
Expanding Scales and Applications for 2D Spatial Mapping of CO2 using GreenLITE
NASA Astrophysics Data System (ADS)
Erxleben, W. H.; Dobler, J. T.; Zaccheo, T. S.; Blume, N.; Braun, M.
2015-12-01
The Greenhouse gas Laser Imaging Tomography Experiment (GreenLITE) system is a new measurement approach originally developed under a cooperative agreement with the Department of Energy (DOE) National Energy Technology Laboratory (NETL), Atmospheric Environmental Sciences (AER) and Exelis Inc. (now part of Harris Corp.). The original system design provides 24/7 monitoring of Ground Carbon Storage (GCS) sites, in order to help ensure worker safety and verify 99% containment. The first generation was designed to cover up to 1km2 area, and employs the Exelis Continuous Wave (CW) Intensity Modulated (IM) approach to measure differential transmission. A pair of scanning transceivers was built and combined with a series of retro reflectors, and a local weather station to provide the information required for producing estimates of the atmospheric CO2 concentration over a number of overlapping lines-of-site. The information from the transceivers, and weather station, are sent remotely to a web-based processing and storage tool, which in-turn uses the data to generate estimates of the 2D spatial distribution over the area of coverage and disseminate that information near real-time via a secure web interface. Recently, in 2015, Exelis and AER have invested in the expansion of the GreenLITE transceiver system to 5 km range, enabling areas up to 25 km2 to be evaluated with this technology, and opening new possibilities for applications such as urban scale monitoring. The 5 km system is being tested in conjunction with the National Institute of Standards and Technology at the Boulder Atmospheric Observatory in August of this year. This talk will review the initial GreenLITE system, testing and deployment of that system, and the more recent development, expansion and testing of the 5 km system.
NASA Astrophysics Data System (ADS)
Červený, Vlastislav; Pšenčík, Ivan
2017-08-01
Integral superposition of Gaussian beams is a useful generalization of the standard ray theory. It removes some of the deficiencies of the ray theory like its failure to describe properly behaviour of waves in caustic regions. It also leads to a more efficient computation of seismic wavefields since it does not require the time-consuming two-point ray tracing. We present the formula for a high-frequency elementary Green function expressed in terms of the integral superposition of Gaussian beams for inhomogeneous, isotropic or anisotropic, layered structures, based on the dynamic ray tracing (DRT) in Cartesian coordinates. For the evaluation of the superposition formula, it is sufficient to solve the DRT in Cartesian coordinates just for the point-source initial conditions. Moreover, instead of seeking 3 × 3 paraxial matrices in Cartesian coordinates, it is sufficient to seek just 3 × 2 parts of these matrices. The presented formulae can be used for the computation of the elementary Green function corresponding to an arbitrary direct, multiply reflected/transmitted, unconverted or converted, independently propagating elementary wave of any of the three modes, P, S1 and S2. Receivers distributed along or in a vicinity of a target surface may be situated at an arbitrary part of the medium, including ray-theory shadow regions. The elementary Green function formula can be used as a basis for the computation of wavefields generated by various types of point sources (explosive, moment tensor).
NASA Technical Reports Server (NTRS)
Plante, Ianik; Cucinotta, Francis A.
2011-01-01
Radiolytic species are formed approximately 1 ps after the passage of ionizing radiation through matter. After their formation, they diffuse and chemically react with other radiolytic species and neighboring biological molecules, leading to various oxidative damage. Therefore, the simulation of radiation chemistry is of considerable importance to understand how radiolytic species damage biological molecules [1]. The step-by-step simulation of chemical reactions is difficult, because the radiolytic species are distributed non-homogeneously in the medium. Consequently, computational approaches based on Green functions for diffusion-influenced reactions should be used [2]. Recently, Green functions for more complex type of reactions have been published [3-4]. We have developed exact random variate generators of these Green functions [5], which will allow us to use them in radiation chemistry codes. Moreover, simulating chemistry using the Green functions is which is computationally very demanding, because the probabilities of reactions between each pair of particles should be evaluated at each timestep [2]. This kind of problem is well adapted for General Purpose Graphic Processing Units (GPGPU), which can handle a large number of similar calculations simultaneously. These new developments will allow us to include more complex reactions in chemistry codes, and to improve the calculation time. This code should be of importance to link radiation track structure simulations and DNA damage models.
2017-12-08
1088793. 3. R. Price and P. E. Green, Jr., “Signal processing in radar astronomy – communication via fluctuating multipath media,” rept. 234, MIT...Lincoln Laboratory (October 1960). 4. P. E. Green, Jr., “Radar astronomy measurement techniques,” rept. 282, MIT Lincoln Laboratory (December 1962). 5. A
ERIC Educational Resources Information Center
Warner, Paul D.; Clearfield, Frank
The Green Thumb Project was designed to test the feasibility of operating a computerized system for disseminating weather, market, and other agricultural production and management information on a day-to-day basis; to develop a prototype software support system for the test; and to provide essential project information on conduct of the test to…
Efficient three-dimensional Poisson solvers in open rectangular conducting pipe
NASA Astrophysics Data System (ADS)
Qiang, Ji
2016-06-01
Three-dimensional (3D) Poisson solver plays an important role in the study of space-charge effects on charged particle beam dynamics in particle accelerators. In this paper, we propose three new 3D Poisson solvers for a charged particle beam in an open rectangular conducting pipe. These three solvers include a spectral integrated Green function (IGF) solver, a 3D spectral solver, and a 3D integrated Green function solver. These solvers effectively handle the longitudinal open boundary condition using a finite computational domain that contains the beam itself. This saves the computational cost of using an extra larger longitudinal domain in order to set up an appropriate finite boundary condition. Using an integrated Green function also avoids the need to resolve rapid variation of the Green function inside the beam. The numerical operational cost of the spectral IGF solver and the 3D IGF solver scales as O(N log(N)) , where N is the number of grid points. The cost of the 3D spectral solver scales as O(Nn N) , where Nn is the maximum longitudinal mode number. We compare these three solvers using several numerical examples and discuss the advantageous regime of each solver in the physical application.
New Radio Telescope Makes First Scientific Observations
NASA Astrophysics Data System (ADS)
2001-05-01
The world's two largest radio telescopes have combined to make detailed radar images of the cloud-shrouded surface of Venus and of a tiny asteroid that passed near the Earth. The images mark the first scientific contributions from the National Science Foundation's (NSF) new Robert C. Byrd Green Bank Telescope in West Virginia, which worked with the NSF's recently-upgraded Arecibo telescope in Puerto Rico. The project used the radar transmitter on the Arecibo telescope and the huge collecting areas of both telescopes to receive the echoes. GBT-Arecibo Radar Image of Maxwell Montes on Venus "These images are the first of many scientific contributions to come from the Robert C. Byrd Green Bank Telescope, and a great way for it to begin its scientific career," said Paul Vanden Bout, director of the National Radio Astronomy Observatory (NRAO). "Our congratulations go to the scientists involved in this project as well as to the hard-working staffs at Green Bank and Arecibo who made this accomplishment possible," Vanden Bout added. To the eye, Venus hides behind a veil of brilliant white clouds, but these clouds can be penetrated by radar waves, revealing the planet's surface. The combination of the Green Bank Telescope (GBT), the world's largest fully-steerable radio telescope, and the Arecibo telescope, the world's most powerful radar, makes an unmatched tool for studying Venus and other solar-system bodies. "Having a really big telescope like the new Green Bank Telescope to receive the radar echoes from small asteroids that are really close to the Earth and from very distant objects like Titan, the large moon of Saturn, will be a real boon to radar studies of the solar system." said Cornell University professor Donald Campbell, leader of the research team. Ten years ago, the radar system on NASA's Magellan spacecraft probed though the clouds of Venus to reveal in amazing detail the surface of the Earth's twin planet. These new studies using the GBT and Arecibo, the first since Magellan to cover large areas of the planet's surface, will provide images showing surface features as small as about 1 km (3,000 ft), only three times the size of the Arecibo telescope itself. Venus may be a geologically active planet similar to the Earth, and the new images will be used to look for changes on Venus due to volcanic activity, landslides and other processes that may have modified the surface since the Magellan mission. The radar echoes received by both telescopes also can be combined to form a radar interferometer capable of measuring altitudes over some of the planet's mountainous regions with considerably better detail than was achieved by Magellan. These were the first scheduled observations with the new Robert C. Byrd Green Bank Telescope, demonstrating its capabilities for solar-system studies. In addition to the observations of Venus, a tiny 150m (500 ft) asteroid, 2001 EC16, was imaged with the two telescopes working as a combined radar system on March 26 when the asteroid was only 8 times the distance of the Moon from the Earth. The image could show details on the asteroid's surface only 15 meters (50 ft) in size and shows EC16 to be an irregularly shaped object rotating about once every 200 hrs, one of the slowest rotation rates so far measured for these objects. It took about 20 seconds for the radar signal to go to EC16 and back, compared with the almost 5 minutes needed to go to Venus and back. EC16 was discovered by the NEAT asteroid survey on March 15, 11 days prior to the radar observations. Very large numbers of these near-Earth asteroids are being discovered and the combined Arecibo-GBT radar system will be needed to properly study a significant number of them. The Robert C. Byrd Green Bank Telescope The observing team led by Campbell also included Jean-Luc Margot of Caltech, Lynn Carter of Cornell, and Bruce Campbell of the Smithsonian Institution. The 100-meter (330 feet) Robert C. Byrd Green Bank Telescope was dedicated in August 2000 and now is being prepared for routine scientific operation. It is operated by the National Radio Astronomy Observatory, headquartered in Charlottesville, Virginia. It is the largest fully-steerable telescope in the world. It is a highly advanced telescope with a mechanized reflecting surface and a laser measurement system for continuous adjustments to its structure. The 305-meter (1,000 feet) Arecibo telescope recently has completed a major upgrade funded by the NSF and NASA to improve its observing capabilities, including a more powerful radar transmitter for planetary studies. It is operated by the National Astronomy and Ionosphere Center (NAIC) headquartered at Cornell University. Its reflector is fixed to the ground, and is the largest telescope of any type in the world. The radar capability of Arecibo, combined with the large reflectors of Arecibo and Green Bank, make for a uniquely powerful radar imaging capability. Both observatories are facilities of the National Science Foundation. The NRAO is operated for the NSF by Associated Universities, Inc., under a cooperative agreement. NAIC is operated by Cornell University, also under a cooperative agreement with the NSF.
Improved Weather Forecasting for the Dynamic Scheduling System of the Green Bank Telescope
NASA Astrophysics Data System (ADS)
Henry, Kari; Maddalena, Ronald
2018-01-01
The Robert C Byrd Green Bank Telescope (GBT) uses a software system that dynamically schedules observations based on models of vertical weather forecasts produced by the National Weather Service (NWS). The NWS provides hourly forecasted values for ~60 layers that extend into the stratosphere over the observatory. We use models, recommended by the Radiocommunication Sector of the International Telecommunications Union, to derive the absorption coefficient in each layer for each hour in the NWS forecasts and for all frequencies over which the GBT has receivers, 0.1 to 115 GHz. We apply radiative transfer models to derive the opacity and the atmospheric contributions to the system temperature, thereby deriving forecasts applicable to scheduling radio observations for up to 10 days into the future. Additionally, the algorithms embedded in the data processing pipeline use historical values of the forecasted opacity to calibrate observations. Until recently, we have concentrated on predictions for high frequency (> 15 GHz) observing, as these need to be scheduled carefully around bad weather. We have been using simple models for the contribution of rain and clouds since we only schedule low-frequency observations under these conditions. In this project, we wanted to improve the scheduling of the GBT and data calibration at low frequencies by deriving better algorithms for clouds and rain. To address the limitation at low frequency, the observatory acquired a Radiometrics Corporation MP-1500A radiometer, which operates in 27 channels between 22 and 30 GHz. By comparing 16 months of measurements from the radiometer against forecasted system temperatures, we have confirmed that forecasted system temperatures are indistinguishable from those measured under good weather conditions. Small miss-calibrations of the radiometer data dominate the comparison. By using recalibrated radiometer measurements, we looked at bad weather days to derive better models for forecasting the contribution of clouds to the opacity and system temperatures. We will show how these revised algorithms should help us improve both data calibration and the accuracy of scheduling low-frequency observations.
Considerations in Using Computer for Presentation.
ERIC Educational Resources Information Center
Lee, Shih-chung
1997-01-01
Addresses issues to consider in conducting computer presentations. Discusses presentation devices--television, multiscan capable monitor, LCD (liquid crystal display) panel with overhead projector, and video/RGB (red, green, blue) projector; lighting; audience size; and types of presentations--fast/short time multimedia presentations, oral and…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Arifvianto, B., E-mail: b.arifvianto@tudelft.nl; L
The present research was aimed at gaining an understanding of the porous structure changes from the green body through water leaching and sintering to titanium scaffolds. Micro-computed tomography (micro-CT) was performed to generate 3D models of titanium scaffold preforms containing carbamide space-holding particles and sintered scaffolds containing macro- and micro-pores. The porosity values and structural parameters were determined by means of image analysis. The result showed that the porosity values, macro-pore sizes, connectivity densities and specific surface areas of the titanium scaffolds sintered at 1200 °C for 3 h did not significantly deviate from those of the green structures withmore » various volume fractions of the space holder. Titanium scaffolds with a maximum specific surface area could be produced with an addition of 60–65 vol% carbamide particles to the matrix powder. The connectivity of pores inside the scaffold increased with rising volume fraction of the space holder. The shrinkage of the scaffolds prepared with > 50 vol% carbamide space holder, occurring during sintering, was caused by the reductions of macro-pore sizes and micro-pore sizes as well as the thickness of struts. In conclusion, the final porous structural characteristics of titanium scaffolds could be estimated from those of the green body. - Highlights: •Porous structures of green body and sintered titanium scaffolds was studied. •Porous structures of both samples were quantitatively characterized with micro-CT. •Porous structures of scaffolds could be controlled from the green body. •Shrinkage mechanisms of titanium scaffolds during sintering was established.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nitao, J J
The goal of the Event Reconstruction Project is to find the location and strength of atmospheric release points, both stationary and moving. Source inversion relies on observational data as input. The methodology is sufficiently general to allow various forms of data. In this report, the authors will focus primarily on concentration measurements obtained at point monitoring locations at various times. The algorithms being investigated in the Project are the MCMC (Markov Chain Monte Carlo), SMC (Sequential Monte Carlo) Methods, classical inversion methods, and hybrids of these. They refer the reader to the report by Johannesson et al. (2004) for explanationsmore » of these methods. These methods require computing the concentrations at all monitoring locations for a given ''proposed'' source characteristic (locations and strength history). It is anticipated that the largest portion of the CPU time will take place performing this computation. MCMC and SMC will require this computation to be done at least tens of thousands of times. Therefore, an efficient means of computing forward model predictions is important to making the inversion practical. In this report they show how Green's functions and reciprocal Green's functions can significantly accelerate forward model computations. First, instead of computing a plume for each possible source strength history, they can compute plumes from unit impulse sources only. By using linear superposition, they can obtain the response for any strength history. This response is given by the forward Green's function. Second, they may use the law of reciprocity. Suppose that they require the concentration at a single monitoring point x{sub m} due to a potential (unit impulse) source that is located at x{sub s}. instead of computing a plume with source location x{sub s}, they compute a ''reciprocal plume'' whose (unit impulse) source is at the monitoring locations x{sub m}. The reciprocal plume is computed using a reversed-direction wind field. The wind field and transport coefficients must also be appropriately time-reversed. Reciprocity says that the concentration of reciprocal plume at x{sub s} is related to the desired concentration at x{sub m}. Since there are many less monitoring points than potential source locations, the number of forward model computations is drastically reduced.« less
Changing Working Habits at Observatories: More Efficiency for Better Science
NASA Astrophysics Data System (ADS)
Veillet, Christian
2012-08-01
Moving away from the widely used model of astronomers going to the telescope to conduct their observations is a trend that is being adopted by an increasing number of facilities. Instead of degrading the data, staff-made observations are actually overall providing better results, as they use the conditions best suited to each program and are done by well-trained observers. The next step is to realize that a PhD is not at all needed to perform these observations: up to some extent, even the night selection of "what to do when" can be left to a well-trained AI-based computer. On the technical side, observing remotely without anybody at the telescope allows for a more relaxed observing environment, leading to better observations. As the telescope is now far from the operator, remote sensing is indispensable and allows for continuous and automatic monitoring, opening the door to automatic alerting when equipment shows signs of problems before they become a real failure. The reliability of the observatory improves and the time lost to failures is dramatically decreased, leading to a much lower level of stress for the technical staff. Using our experience at the Canada-France-Hawaii Telescope, we will explore the practical consequences of this evolution, not only on the performance of the observatory, but also on the changes it entails on the overall redistribution of the work within the observatory, and on the relationship between the staff and the astronomical community, culminating with the notion that an observatory is first and foremost a service provider.
Environment Study of AGNs at z = 0.3 to 3.0 Using the Japanese Virtual Observatory
NASA Astrophysics Data System (ADS)
Shirasaki, Y.; Ohishi, M.; Mizumoto, Y.; Takata, T.; Tanaka, M.; Yasuda, N.
2010-12-01
We present a science use case of Virtual Observatory, which was achieved to examine an environment of AGN up to redshift of 3.0. We used the Japanese Virtual Observatory (JVO) to obtain Subaru Suprime-Cam images around known AGNs. According to the hierarchical galaxy formation model, AGNs are expected to be found in an environment of higher galaxy density than that of typical galaxies. The current observations, however, indicate that AGNs do not reside in a particularly high density environment. We investigated ˜1000 AGNs, which is about ten times larger samples than the other studies covering the redshifts larger than 0.6. We successfully found significant excess of galaxies around AGNs at redshifts of 0.3 to 1.8. If this work was done in a classical manner, that is, raw data were retrieved from the archive through a form-based web interface in an interactive way, and the data were reduced on a low performance computer, it might take several years to finish it. Since the Virtual Observatory system is accessible through a standard interface, it is easy to query and retrieve data in an automatic way. We constructed a pipeline for retrieving the data and calculating the galaxy number density around a given coordinate. This procedure was executed in parallel on ˜10 quad core PCs, and it took only one day for obtaining the final result. Our result implies that the Virtual Observatory can be a powerful tool to do an astronomical research based on large amount of data.
NASA Technical Reports Server (NTRS)
1991-01-01
This photograph shows the Compton Gamma-Ray Observatory (GRO) being deployed by the Remote Manipulator System (RMS) arm aboard the Space Shuttle Atlantis during the STS-37 mission in April 1991. The GRO reentered Earth atmosphere and ended its successful mission in June 2000. For nearly 9 years, the GRO Burst and Transient Source Experiment (BATSE), designed and built by the Marshall Space Flight Center (MSFC), kept an unblinking watch on the universe to alert scientists to the invisible, mysterious gamma-ray bursts that had puzzled them for decades. By studying gamma-rays from objects like black holes, pulsars, quasars, neutron stars, and other exotic objects, scientists could discover clues to the birth, evolution, and death of stars, galaxies, and the universe. The gamma-ray instrument was one of four major science instruments aboard the Compton. It consisted of eight detectors, or modules, located at each corner of the rectangular satellite to simultaneously scan the entire universe for bursts of gamma-rays ranging in duration from fractions of a second to minutes. In January 1999, the instrument, via the Internet, cued a computer-controlled telescope at Las Alamos National Laboratory in Los Alamos, New Mexico, within 20 seconds of registering a burst. With this capability, the gamma-ray experiment came to serve as a gamma-ray burst alert for the Hubble Space Telescope, the Chandra X-Ray Observatory, and major gound-based observatories around the world. Thirty-seven universities, observatories, and NASA centers in 19 states, and 11 more institutions in Europe and Russia, participated in the BATSE science program.
History of Chandra X-Ray Observatory
1998-01-01
This is a computer rendering of the fully developed Chandra X-Ray Observatory (CXO), formerly Advanced X-Ray Astrophysics Facility (AXAF). In 1999, the AXAF was renamed the CXO in honor of the late Indian-American Novel Laureate Subrahmanyan Chandrasekhar. The CXO is the most sophisticated and the world's most powerful x-ray telescope ever built. It is designed to observe x-rays from high energy regions of the Universe, such as hot gas in the renmants of exploded stars. It produces picture-like images of x-ray emissions analogous to those made in visible light, as well as gathers data on the chemical composition of x-ray radiating objects. The CXO helps astronomers world-wide better understand the structure and evolution of the universe by studying powerful sources of x-ray such as exploding stars, matter falling into black holes, and other exotic celestial objects. The Observatory has three major parts: (1) the x-ray telescope, whose mirrors will focus x-rays from celestial objects; (2) the science instruments that record the x-rays so that x-ray images can be produced and analyzed; and (3) the spacecraft, which provides the environment necessary for the telescope and the instruments to work. TRW, Inc. was the prime contractor for the development of the CXO and NASA's Marshall Space Flight Center was responsible for its project management. The Smithsonian Astrophysical Observatory controls science and flight operations of the CXO for NASA from Cambridge, Massachusetts. The Observatory was launched July 22, 1999 aboard the Space Shuttle Columbia, STS-93 mission. (Image courtesy of TRW).
History of Chandra X-Ray Observatory
1999-01-01
This is a computer rendering of the fully developed Chandra X-ray Observatory (CXO), formerly Advanced X-Ray Astrophysics Facility (AXAF), in orbit in a star field. In 1999, the AXAF was renamed the CXO in honor of the late Indian-American Novel Laureate Subrahmanyan Chandrasekhar. The CXO is the most sophisticated and the world's most powerful x-ray telescope ever built. It is designed to observe x-rays from high energy regions of the Universe, such as hot gas in the renmants of exploded stars. It produces picture-like images of x-ray emissions analogous to those made in visible light, as well as gathers data on the chemical composition of x-ray radiating objects. The CXO helps astronomers world-wide better understand the structure and evolution of the universe by studying powerful sources of x-rays such as exploding stars, matter falling into black holes, and other exotic celestial objects. The Observatory has three major parts: (1) the x-ray telescope, whose mirrors will focus x-rays from celestial objects; (2) the science instruments that record the x-rays so that x-ray images can be produced and analyzed; and (3) the spacecraft, which provides the environment necessary for the telescope and the instruments to work. TRW, Inc. was the prime contractor for the development of the CXO and NASA's Marshall Space Flight Center was responsible for its project management. The Smithsonian Astrophysical Observatory controls science and flight operations of the CXO for NASA from Cambridge, Massachusetts. The Observatory was launched July 22, 1999 aboard the Space Shuttle Columbia, STS-93 mission. (Image courtesy of TRW).
New Computational Approach to Electron Transport in Irregular Graphene Nanostructures
NASA Astrophysics Data System (ADS)
Mason, Douglas; Heller, Eric; Prendergast, David; Neaton, Jeffrey
2009-03-01
For novel graphene devices of nanoscale-to-macroscopic scale, many aspects of their transport properties are not easily understood due to difficulties in fabricating devices with regular edges. Here we develop a framework to efficiently calculate and potentially screen electronic transport properties of arbitrary nanoscale graphene device structures. A generalization of the established recursive Green's function method is presented, providing access to arbitrary device and lead geometries with substantial computer-time savings. Using single-orbital nearest-neighbor tight-binding models and the Green's function-Landauer scattering formalism, we will explore the transmission function of irregular two-dimensional graphene-based nanostructures with arbitrary lead orientation. Prepared by LBNL under contract DE-AC02-05CH11231 and supported by the U.S. Dept. of Energy Computer Science Graduate Fellowship under grant DE-FG02-97ER25308.
Payload specialist Ronald Parise checks on ASTRO-2 payload
NASA Technical Reports Server (NTRS)
1995-01-01
Payload specialist Ronald A. Parise, a senior scientist in the Space Observatories Department of Computer Sciences Corporation (CSC), checks on the ASTRO-2 payload (out of frame in the cargo bay of the Space Shuttle Endeavour). Parise is on the aft flight deck of the Earth orbiting Endeavour during STS-67.
NASA Marshall Space Flight Center solar observatory report, January - June 1993
NASA Technical Reports Server (NTRS)
Smith, J. E.
1993-01-01
This report provides a description of the NASA Marshall Space Flight Center's Solar Vector Magnetograph Facility and gives a summary of its observations and data reduction during January-June 1993. The systems that make up the facility are a magnetograph telescope, an H-alpha telescope, a Questar telescope, and a computer code.
NASA Marshall Space Flight Center Solar Observatory report, July - October 1993
NASA Technical Reports Server (NTRS)
Smith, J. E.
1994-01-01
This report provides a description of the NASA Marshall Space Flight Center's Solar Vector Magnetograph Facility and gives a summary of its observations and data reduction during June-October 1993. The systems that make up the facility are a magnetograph telescope, an H-alpha telescope, a Questar telescope, and a computer code.
NASA Marshall Space Flight Center Solar Observatory report, March - May 1994
NASA Technical Reports Server (NTRS)
Smith, J. E.
1994-01-01
This report provides a description of the NASA Marshall Space Flight Center's Solar Vector Magnetograph Facility and gives a summary of its observations and data reduction during March-May 1994. The systems that make up the facility are a magnetograph telescope, an H-alpha telescope, a Questar telescope, and a computer code.
Astronomy Education Milestone in Hermanus
NASA Astrophysics Data System (ADS)
de Villiers, Pierre
2010-12-01
A milestone in astronomy awareness and education in South Africa was achieved during October when Hermanus Centre members, together with science teachers and learners from Hermanus High and Qhayiya Secondary School, saw "first light" on the 1,2m MONET North telescope at the McDonald Observatory, Texas via the internet from the Hermanus High School's computer room.
The Theoretical Astrophysical Observatory: Cloud-based Mock Galaxy Catalogs
NASA Astrophysics Data System (ADS)
Bernyk, Maksym; Croton, Darren J.; Tonini, Chiara; Hodkinson, Luke; Hassan, Amr H.; Garel, Thibault; Duffy, Alan R.; Mutch, Simon J.; Poole, Gregory B.; Hegarty, Sarah
2016-03-01
We introduce the Theoretical Astrophysical Observatory (TAO), an online virtual laboratory that houses mock observations of galaxy survey data. Such mocks have become an integral part of the modern analysis pipeline. However, building them requires expert knowledge of galaxy modeling and simulation techniques, significant investment in software development, and access to high performance computing. These requirements make it difficult for a small research team or individual to quickly build a mock catalog suited to their needs. To address this TAO offers access to multiple cosmological simulations and semi-analytic galaxy formation models from an intuitive and clean web interface. Results can be funnelled through science modules and sent to a dedicated supercomputer for further processing and manipulation. These modules include the ability to (1) construct custom observer light cones from the simulation data cubes; (2) generate the stellar emission from star formation histories, apply dust extinction, and compute absolute and/or apparent magnitudes; and (3) produce mock images of the sky. All of TAO’s features can be accessed without any programming requirements. The modular nature of TAO opens it up for further expansion in the future.
Astronomy research via the Internet
NASA Astrophysics Data System (ADS)
Ratnatunga, Kavan U.
Small developing countries may not have a dark site with good seeing for an astronomical observatory or be able to afford the financial commitment to set up and support such a facility. Much of astronomical research today is however done with remote observations, such as from telescopes in space, or obtained by service observing at large facilities on the ground. Cutting-edge astronomical research can now be done with low-cost computers, with a good Internet connection to get on-line access to astronomical observations, journals and most recent preprints. E-mail allows fast easy collaboration between research scientitists around the world. An international program with some short-term collaborative visits, could mine data and publish results from available astronomical observations for a fraction of the investment and cost of running even a small local observatory. Students who have been trained in the use of computers and software by such a program would also be more employable in the current job market. The Internet can reach you wherever you like to be and give you direct access to whatever you need for astronomical research.
SHARPs - A Near-Real-Time Space Weather Data Product from HMI
NASA Astrophysics Data System (ADS)
Bobra, M.; Turmon, M.; Baldner, C.; Sun, X.; Hoeksema, J. T.
2012-12-01
A data product from the Helioseismic and Magnetic Imager (HMI) on the Solar Dynamics Observatory (SDO), called Space-weather HMI Active Region Patches (SHARPs), is now available through the SDO Joint Science Operations Center (JSOC) and the Virtual Solar Observatory. SHARPs are magnetically active regions identified on the solar disk and tracked automatically in time. SHARP data are processed within a few hours of the observation time. The SHARP data series contains active region-sized disambiguated vector magnetic field data in both Lambert Cylindrical Equal-Area and CCD coordinates on a 12 minute cadence. The series also provides simultaneous HMI maps of the line-of-sight magnetic field, continuum intensity, and velocity on the same ~0.5 arc-second pixel grid. In addition, the SHARP data series provides space weather quantities computed on the inverted, disambiguated, and remapped data. The values for each tracked region are computed and updated in near real time. We present space weather results for several X-class flares; furthermore, we compare said space weather quantities with helioseismic quantities calculated using ring-diagram analysis.
Design Considerations of Polishing Lap for Computer-Controlled Cylindrical Polishing Process
NASA Technical Reports Server (NTRS)
Khan, Gufran S.; Gubarev, Mikhail; Speegle, Chet; Ramsey, Brian
2010-01-01
The future X-ray observatory missions, such as International X-ray Observatory, require grazing incidence replicated optics of extremely large collecting area (3 m2) in combination with angular resolution of less than 5 arcsec half-power diameter. The resolution of a mirror shell depends ultimately on the quality of the cylindrical mandrels from which they are being replicated. Mid-spatial-frequency axial figure error is a dominant contributor in the error budget of the mandrel. This paper presents our efforts to develop a deterministic cylindrical polishing process in order to keep the mid-spatial-frequency axial figure errors to a minimum. Simulation studies have been performed to optimize the operational parameters as well as the polishing lap configuration. Furthermore, depending upon the surface error profile, a model for localized polishing based on dwell time approach is developed. Using the inputs from the mathematical model, a mandrel, having conical approximated Wolter-1 geometry, has been polished on a newly developed computer-controlled cylindrical polishing machine. We report our first experimental results and discuss plans for further improvements in the polishing process.
A virtual reality environment for telescope operation
NASA Astrophysics Data System (ADS)
Martínez, Luis A.; Villarreal, José L.; Ángeles, Fernando; Bernal, Abel
2010-07-01
Astronomical observatories and telescopes are becoming increasingly large and complex systems, demanding to any potential user the acquirement of great amount of information previous to access them. At present, the most common way to overcome that information is through the implementation of larger graphical user interfaces and computer monitors to increase the display area. Tonantzintla Observatory has a 1-m telescope with a remote observing system. As a step forward in the improvement of the telescope software, we have designed a Virtual Reality (VR) environment that works as an extension of the remote system and allows us to operate the telescope. In this work we explore this alternative technology that is being suggested here as a software platform for the operation of the 1-m telescope.
More than a solar cycle of synoptic solar and coronal data - A video presentation
NASA Technical Reports Server (NTRS)
Hoeksema, J. T.; Scherrer, P. H.; Herant, M.; Title, A. M.
1988-01-01
Color video movies of synoptic observations of the sun and corona can now be created. Individual analog frames on laser disks can be referenced digitally and played back at any speed. We have brought together photospheric magnetic field data from the Wilcox Solar Observatory at Stanford and the National Solar Observatory, model computations of the coronal magnetic field, and coronal data from the Sacramento Peak coronagraph and the Mauna Loa K-coronameter and made a series of movies presenting the data sets individually and in comparison with one another. This paper presents a description of each of the data sets and movies developed thus far and briefly outlines some of the more interesting and obvious features observed when viewing the movies.
NASA Astrophysics Data System (ADS)
Abdulkadyrov, Magomed A.; Belousov, Sergey P.; Patrikeev, Vladimir E.; Semenov, Alexandr P.
2010-07-01
Since last years and at present days LZOS, JSC has been producing a range of primary mirrors of astronomical telescopes with diameter more than 1m under contracts with foreign companies. Simultaneous testing of an aspherical surface figure by means of a lens corrector and CGH (computer generated hologram) corrector, testing of the corrector using the CGH allow challenging the task of definite testing of the mirrors surfaces figure. The results of successful figuring of the mirrors with diameter up to 4m like VISTA Project (Southern European Observatory), TNT (Thai National telescope, Australia - Thailand), LCO telescopes (Las Cumbres Observatory, USA; Russian national projects and meeting these mirrors specifications' requirements are all considered as the sufficient evidence.
ERIC Educational Resources Information Center
Hignite, Karla
2009-01-01
Green information technology (IT) is grabbing more mainstream headlines--and for good reason. Computing, data processing, and electronic file storage collectively account for a significant and growing share of energy consumption in the business world and on higher education campuses. With greater scrutiny of all activities that contribute to an…
Green roof hydrologic performance and modeling: a review.
Li, Yanling; Babcock, Roger W
2014-01-01
Green roofs reduce runoff from impervious surfaces in urban development. This paper reviews the technical literature on green roof hydrology. Laboratory experiments and field measurements have shown that green roofs can reduce stormwater runoff volume by 30 to 86%, reduce peak flow rate by 22 to 93% and delay the peak flow by 0 to 30 min and thereby decrease pollution, flooding and erosion during precipitation events. However, the effectiveness can vary substantially due to design characteristics making performance predictions difficult. Evaluation of the most recently published study findings indicates that the major factors affecting green roof hydrology are precipitation volume, precipitation dynamics, antecedent conditions, growth medium, plant species, and roof slope. This paper also evaluates the computer models commonly used to simulate hydrologic processes for green roofs, including stormwater management model, soil water atmosphere and plant, SWMS-2D, HYDRUS, and other models that are shown to be effective for predicting precipitation response and economic benefits. The review findings indicate that green roofs are effective for reduction of runoff volume and peak flow, and delay of peak flow, however, no tool or model is available to predict expected performance for any given anticipated system based on design parameters that directly affect green roof hydrology.
The Green Bank Telescope: First Full Winter of Operation at 3mm
NASA Astrophysics Data System (ADS)
Lockman, Felix J.
2017-06-01
The winter of 2016-2017 marks the first season for the Green Bank Telescope (GBT) with full instrumentation in the 3mm band. ARGUS, a 16-pixel array, provides spectroscopic capabilities over 80-116 GHz. MUSTANG-2, a 223 pixel bolometer array, provides extremely sensitive continuum mapping capabilities over a 30 GHz band centered on 90 GHz at an angular resolution of 9”. In addition, there is a 2-pixel receiver that covers the lower part of the 3mm band, 67-93 GHz, for spectroscopy, continuum measurements, and VLBI.In March, under good night-time conditions, the GBT angular resolution at 109 GHz was measured to be 6.5”. This corresponds to 1.16 lambda/Diameter, exactly as expected from theoretical considerations and identical to the wavelength/Diameter ratio measured at much lower frequencies. Near sidelobe levels are below -20 dB.This poster will review some results that highlight the GBT’s new capabilities in the 3mm band, including new insights into the origin of the anomalous microwave emission, 13CO measurements of a cloud in the Milky Way halo that is in the process making the transition between atomic and molecular gas, HCO+ measurements of infall in a star-forming region, and measurements of dust emission and its spectrum in Orion.The Green Bank Observatory is a facility of the National Science Foundation, operated under a cooperative agreement by Associated Universities, Inc.
Optical observational programs at the Indian Institute of Astrophysics
NASA Astrophysics Data System (ADS)
Singh, Jagdev; Ravindra, B.
The Indian Institute of Astrophysics has been making optical observations of the sun for more than a century by taking images of the sun in continuum to study the photosphere, Ca-K line and H-alpha line in order to study the chromosphere by using the same instruments which are used to study the long term variations of the magnetic fields on the sun. The digitizers have been developed using uniform light sources, imaging optics without any vignetting in the required FOV and large format 4K×4K CCD cameras to digitize the data for scientific studies. At the Solar Tower Telescope we have performed very high resolution spectroscopic observations around Ca-K line to investigate the variations and delineate the contribution of various features to the solar cycle variations. Solar coronal studies have been done during the occurrence of total solar eclipses and with a coronagraph to study the coronal heating. Here we discuss the systematic temporal variations observed in the green and red emission profiles using high spectral and temporal observations during the 2006, 2009 and 2010 total solar eclipses. The TWIN telescope a new facility has been fabricated and installed at Kodaikanal observatory to continue the synoptic observations of the sun and a space-based coronagraph is also being designed and fabricated in collaboration with various laboratories of ISRO (LEOS, ISAC and SAC) and USO. In this article we present the summary of results of optical observational programs carried out at Kodaikanal Observatory and during the eclipse expeditions where authors have played a leading role. Furthermore, this review is not complete in all respects of all the observational programs carried out at the Kodaikanal observatory.
A green observatory in the Chilean Atacama desert
NASA Astrophysics Data System (ADS)
Ramolla, Michael; Westhues, Christian; Hackstein, Moritz; Haas, Martin; Hodapp, Klaus; Lemke, Roland; Barr Domínguez, Angie; Chini, Rolf; Murphy, Miguel
2016-08-01
Since 2007, the Ruhr-Universität Bochum (RUB) in Germany and Universidad Católica del Norte (UCN) in Chile jointly operate the Universitätssternwarte der Ruhr-Universität Bochum (USB), which is located in direct neighborhood of the future E-ELT of ESO. It is the only observatory powered exclusively by solar panels and wind turbines. Excess power is stored in batteries that allow uninterrupted operation even in windless nights. The scientific equipment consists of three robotic optical telescopes with apertures ranging from 15 cm (RoBoTT) over 25 cm (BESTII) to 40 cm (BMT) and one 80 cm (IRIS) infra-red telescope. The optical telescopes are equipped with Johnson and Sloan broad band filters together with a large number of narrow and intermediate bands. In the infrared, J,H and K filters are available, accompanied by several narrow bands near the K band wavelength. The second Nasmyth focus in the 80 cm telescope feeds a high resolution echelle spectrograph similar to the FEROS instrument of ESO. This variety of instruments has evolved from different collaborations, i.e. with the University of Hawaii (IfA) in the USA, which provided the near-infrared-camera of the IRIS telescope, or with the Deutsches Zentrum für Luft- und Raumfahrt (DLR) in Germany, which provided the BESTII telescope. The highly automatized processes on all telescopes enable a single person to run the whole facility, providing the high cost efficiency required for an university observatory. The excellent site conditions allow projects that require daily observations of astronomical objects over epochs of several months or years. Here we report on such studies of young stellar objects from the Bochum Galactic Disk Survey, the multiplicity of stars, quasar variability or the hunt for exo-planets.
Nonequilibrium Green's function theory for nonadiabatic effects in quantum electron transport
NASA Astrophysics Data System (ADS)
Kershaw, Vincent F.; Kosov, Daniel S.
2017-12-01
We develop nonequilibrium Green's function-based transport theory, which includes effects of nonadiabatic nuclear motion in the calculation of the electric current in molecular junctions. Our approach is based on the separation of slow and fast time scales in the equations of motion for Green's functions by means of the Wigner representation. Time derivatives with respect to central time serve as a small parameter in the perturbative expansion enabling the computation of nonadiabatic corrections to molecular Green's functions. Consequently, we produce a series of analytic expressions for non-adiabatic electronic Green's functions (up to the second order in the central time derivatives), which depend not solely on the instantaneous molecular geometry but likewise on nuclear velocities and accelerations. An extended formula for electric current is derived which accounts for the non-adiabatic corrections. This theory is concisely illustrated by the calculations on a model molecular junction.
Nonequilibrium Green's function theory for nonadiabatic effects in quantum electron transport.
Kershaw, Vincent F; Kosov, Daniel S
2017-12-14
We develop nonequilibrium Green's function-based transport theory, which includes effects of nonadiabatic nuclear motion in the calculation of the electric current in molecular junctions. Our approach is based on the separation of slow and fast time scales in the equations of motion for Green's functions by means of the Wigner representation. Time derivatives with respect to central time serve as a small parameter in the perturbative expansion enabling the computation of nonadiabatic corrections to molecular Green's functions. Consequently, we produce a series of analytic expressions for non-adiabatic electronic Green's functions (up to the second order in the central time derivatives), which depend not solely on the instantaneous molecular geometry but likewise on nuclear velocities and accelerations. An extended formula for electric current is derived which accounts for the non-adiabatic corrections. This theory is concisely illustrated by the calculations on a model molecular junction.
NASA Astrophysics Data System (ADS)
Kamnik, Rok; Grajfoner, Blanka; Butyrin, Andrey; Nekrep Perc, Matjaz
2017-10-01
The objective of this work is to use simple photogrammetry to evaluate rainwater harvesting and green area retention potential in Maribor, Slovenia city centre. Several sources of remote sensing data have been described and a field test with semi-professional drone was performed by means of computer evaluation of rainwater harvesting and green area retention potential. Some of the most important design parameters for rainwater harvesting systems as roof area and slope and available green areas were identified and evaluated. The results have shown that even semi-professional low budget drones can be successfully used for mapping areas of interest. The results of six-minute flight over twelve hectares of Maribor city centre were comparable with professional results of plane remote sensing. Image segmentation from orthomosaic together with elevation model has been used to detect roofs and green areas.
Method to manage integration error in the Green-Kubo method.
Oliveira, Laura de Sousa; Greaney, P Alex
2017-02-01
The Green-Kubo method is a commonly used approach for predicting transport properties in a system from equilibrium molecular dynamics simulations. The approach is founded on the fluctuation dissipation theorem and relates the property of interest to the lifetime of fluctuations in its thermodynamic driving potential. For heat transport, the lattice thermal conductivity is related to the integral of the autocorrelation of the instantaneous heat flux. A principal source of error in these calculations is that the autocorrelation function requires a long averaging time to reduce remnant noise. Integrating the noise in the tail of the autocorrelation function becomes conflated with physically important slow relaxation processes. In this paper we present a method to quantify the uncertainty on transport properties computed using the Green-Kubo formulation based on recognizing that the integrated noise is a random walk, with a growing envelope of uncertainty. By characterizing the noise we can choose integration conditions to best trade off systematic truncation error with unbiased integration noise, to minimize uncertainty for a given allocation of computational resources.
Method to manage integration error in the Green-Kubo method
NASA Astrophysics Data System (ADS)
Oliveira, Laura de Sousa; Greaney, P. Alex
2017-02-01
The Green-Kubo method is a commonly used approach for predicting transport properties in a system from equilibrium molecular dynamics simulations. The approach is founded on the fluctuation dissipation theorem and relates the property of interest to the lifetime of fluctuations in its thermodynamic driving potential. For heat transport, the lattice thermal conductivity is related to the integral of the autocorrelation of the instantaneous heat flux. A principal source of error in these calculations is that the autocorrelation function requires a long averaging time to reduce remnant noise. Integrating the noise in the tail of the autocorrelation function becomes conflated with physically important slow relaxation processes. In this paper we present a method to quantify the uncertainty on transport properties computed using the Green-Kubo formulation based on recognizing that the integrated noise is a random walk, with a growing envelope of uncertainty. By characterizing the noise we can choose integration conditions to best trade off systematic truncation error with unbiased integration noise, to minimize uncertainty for a given allocation of computational resources.
Astroinformatics as a New Research Field. UkrVO Astroinformation Resources: Tasks and Prospective
NASA Astrophysics Data System (ADS)
Vavilova, I. B.
The data-oriented astronomy has allowed classifying the Astroinformatics as a new academic research field, which covers various multi-disciplinary applications of the e-Astronomy. Among them are the data modeling, data mining, metadata standards development, data access, digital astronomical databases, image archives and visualization, machine learning, statistics and other computational methods and software for work with astronomical survey and catalogues with their teta- topeta-scale astroinformation resource. In this review we describe briefly the astroinformatics applications and software/services performed for different astronomical tasks in frame of the VIrtual Roentgen and Gamma Observatory (VIRGO) and Ukrainian VirtualObservatory (UkrVO). Among them there are projects based on the archival space-born data of X-ray and gamma space observatories and on the Joint Digitized Archive (JDA) database of astroplate network collections. The UkrVO JDA DR1 deals with the star catalogues (FON, Polar zone, open clusters, GRB star fields) as well as the UkrVO JDA DR2 deals with the Solar System bodies (giant and small planets, satellites, astronomical heritage images).
Framework for Informed Policy Making Using Data from National Environmental Observatories
NASA Astrophysics Data System (ADS)
Wee, B.; Taylor, J. R.; Poinsatte, J.
2012-12-01
Large-scale environmental changes pose challenges that straddle environmental, economic, and social boundaries. As we design and implement climate adaptation strategies at the Federal, state, local, and tribal levels, accessible and usable data are essential for implementing actions that are informed by the best available information. Data-intensive science has been heralded as an enabler for scientific breakthroughs powered by advanced computing capabilities and interoperable data systems. Those same capabilities can be applied to data and information systems that facilitate the transformation of data into highly processed products. At the interface of scientifically informed public policy and data intensive science lies the potential for producers of credible, integrated, multi-scalar environmental data like the National Ecological Observatory Network (NEON) and its partners to capitalize on data and informatics interoperability initiatives that enable the integration of environmental data from across credible data sources. NSF's large-scale environmental observatories such as NEON and the Ocean Observatories Initiative (OOI) are designed to provide high-quality, long-term environmental data for research. These data are also meant to be repurposed for operational needs that like risk management, vulnerability assessments, resource management, and others. The proposed USDA Agriculture Research Service (ARS) Long Term Agro-ecosystem Research (LTAR) network is another example of such an environmental observatory that will produce credible data for environmental / agricultural forecasting and informing policy. To facilitate data fusion across observatories, there is a growing call for observation systems to more closely coordinate and standardize how variables are measured. Together with observation standards, cyberinfrastructure standards enable the proliferation of an ecosystem of applications that utilize diverse, high-quality, credible data. Interoperability facilitates the integration of data from multiple credible sources of data, and enables the repurposing of data for use at different geographical scales. Metadata that captures the transformation of data into value-added products ("provenance") lends reproducability and transparency to the entire process. This way, the datasets and model code used to create any product can be examined by other parties. This talk outlines a pathway for transforming environmental data into value-added products by various stakeholders to better inform sustainable agriculture using data from environmental observatories including NEON and LTAR.;
NASA Carbon Sleuth Begins Year Two
2015-10-29
Global average carbon dioxide concentrations as seen by NASA’s Orbiting Carbon Observatory-2 mission, June 1-15, 2015. OCO-2 measures carbon dioxide from the top of Earth's atmosphere to its surface. Higher carbon dioxide concentrations are in red, with lower concentrations in yellows and greens. Scientists poring over data from OCO-2 mission are seeing patterns emerge as they seek answers to questions about atmospheric carbon dioxide. Among the most striking features visible in the first year of OCO-2 data is the increase in carbon dioxide in the northern hemisphere during winter, when trees are not removing carbon dioxide, followed by its decrease in spring, as trees start to grow and remove carbon dioxide from the atmosphere. http://photojournal.jpl.nasa.gov/catalog/PIA20039
2017-12-08
Release date Dec. 30, 2009 In the supernova remnant W49B, Suzaku found another fossil fireball. It detected X-rays produced when heavily ionized iron atoms recapture an electron. This view combines infrared images from the ground (red, green) with X-ray data from NASA's Chandra X-Ray Observatory (blue). Credit: Caltech/SSC/J. Rho and T. Jarrett and NASA/CXC/SSC/J. Keohane et al. To learn more about this image go to: www.nasa.gov/mission_pages/astro-e2/news/fossil-fireballs... NASA Goddard Space Flight Center is home to the nation's largest organization of combined scientists, engineers and technologists that build spacecraft, instruments and new technology to study the Earth, the sun, our solar system, and the universe.
Satellite Sees Holiday Lights Brighten Cities - Saudi Arabia
2017-12-08
In several cities in the Middle East, city lights brighten during the Muslim holy month of Ramadan, as seen using a new analysis of daily data from the NASA-NOAA Suomi NPP satellite. Dark green pixels are areas where the lights are 50 percent brighter, or more, during Ramadan. Credit: Jesse Allen, NASA’s Earth Observatory Read more: www.nasa.gov/content/goddard/satellite-sees-holiday-light... NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram
Sensitivity of Pulsar Timing Arrays
NASA Astrophysics Data System (ADS)
Siemens, Xavier
2015-08-01
For the better part of the last decade, the North American Nanohertz Observatory for Gravitational Waves (NANOGrav) has been using the Green Bank and Arecibo radio telescopes to monitor millisecond pulsars. NANOGrav, along with similar international collaborations, the European Pulsar Timing Array and the Parkes Pulsar Timing Array in Australia, form a consortium of consortia: the International Pulsar Timing Array (IPTA). The goal of the IPTA is to directly detect low-frequency gravitational waves which cause small changes to the times of arrival of radio pulses from millisecond pulsars. In this talk I will discuss the work of NANOGrav and the IPTA as well as our sensitivity to gravitational waves from astrophysical sources. I will show that a detection is possible by the end of the decade.
A Search for Neutrinos from Fast Radio Bursts with IceCube
NASA Astrophysics Data System (ADS)
Fahey, Samuel; Kheirandish, Ali; Vandenbroucke, Justin; Xu, Donglian
2017-08-01
We present a search for neutrinos in coincidence in time and direction with four fast radio bursts (FRBs) detected by the Parkes and Green Bank radio telescopes during the first year of operation of the complete IceCube Neutrino Observatory (2011 May through 2012 May). The neutrino sample consists of 138,322 muon neutrino candidate events, which are dominated by atmospheric neutrinos and atmospheric muons but also contain an astrophysical neutrino component. Considering only neutrinos detected on the same day as each FRB, zero IceCube events were found to be compatible with the FRB directions within the estimated 99% error radius of the neutrino directions. Based on the non-detection, we present the first upper limits on the neutrino fluence from FRBs.
NASA Astrophysics Data System (ADS)
Gibson, Steven R.; Howard, Andrew W.; Marcy, Geoffrey W.; Edelstein, Jerry; Wishnow, Edward H.; Poppett, Claire L.
2016-08-01
KPF is a fiber-fed, high-resolution, high-stability spectrometer in development at the UC Berkeley Space Sciences Laboratory for the W.M. Keck Observatory. The instrument is designed to characterize exoplanets via Doppler spectroscopy with a single measurement precision of 0.5ms-1 or better, however its resolution and stability will enable a wide variety of astrophysical pursuits. KPF will have a 200mm collimated beam diameter and a resolving power of >80,000. The design includes a green channel (440nm to 590 nm) and red channel (590nm to 850 nm). A novel design aspect of KPF is the use of a Zerodur optical bench, and Zerodur optics with integral mounts, to provide stability against thermal expansion and contraction effects.
Satellite Sees Holiday Lights Brighten Cities - Istanbul
2017-12-08
In several cities in the Middle East, city lights brighten during the Muslim holy month of Ramadan, as seen using a new analysis of daily data from the NASA-NOAA Suomi NPP satellite. Dark green pixels are areas where the lights are 50 percent brighter, or more, during Ramadan. Credit: Jesse Allen, NASA’s Earth Observatory Read more: www.nasa.gov/content/goddard/satellite-sees-holiday-light... NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram
Satellite Sees Holiday Lights Brighten Cities - Cairo
2017-12-08
In several cities in the Middle East, city lights brighten during the Muslim holy month of Ramadan, as seen using a new analysis of daily data from the NASA-NOAA Suomi NPP satellite. Dark green pixels are areas where the lights are 50 percent brighter, or more, during Ramadan. Credit: Jesse Allen, NASA’s Earth Observatory Read more: www.nasa.gov/content/goddard/satellite-sees-holiday-light... NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram
Remote monitoring of a Fire Protection System
NASA Astrophysics Data System (ADS)
Bauman, Steven; Vermeulen, Tom; Roberts, Larry; Matsushige, Grant; Gajadhar, Sarah; Taroma, Ralph; Elizares, Casey; Arruda, Tyson; Potter, Sharon; Hoffman, James
2011-03-01
Some years ago CFHT proposed developing a Remote Observing Environment aimed at producing Science Observations at their Observatory Facility on Mauna Kea from their Headquarters facility in Waimea, HI. This Remote Observing Project commonly referred to as OAP (Observatory Automation Project) was completed at the end of January 2011 and has been providing the majority of Science Data since. My poster will discuss the upgrades to the existing fire alarm protection system. With no one at the summit during nightly operations, the observatory facility required automated monitoring of the facility for safety to personnel and equipment in the case of a fire. An addressable analog fire panel was installed which utilizes digital communication protocol (DCP), intelligent communication with other devices, and an RS-232 interface which provides feedback and real-time monitoring of the system. Using the interface capabilities of the panel, it provides notifications when heat detectors, smoke sensors, manual pull stations, or the main observatory computer room fire suppression system has been activated. The notifications are sent out as alerts to staff in the form of test massages and emails and the observing control GUI interface alerts the remote telescope operator with a map showing the location of the fire occurrence and type of device that has been triggered. And all of this was accomplished without the need for an outside vendor to monitor the system and facilitate warnings or notifications regarding the system.
Higashida, Y; Moribe, N; Hirata, Y; Morita, K; Doudanuki, S; Sonoda, Y; Katsuda, N; Hiai, Y; Misumi, W; Matsumoto, M
1988-01-01
Threshold contrasts of low-contrast objects with computed radiography (CR) images were compared with those of blue and green emitting screen-film systems by employing the 18-alternative forced choice (18-AFC) procedure. The dependence of the threshold contrast on the incident X-ray exposure and also the object size was studied. The results indicated that the threshold contrasts of CR system were comparable to those of blue and green screen-film systems and decreased with increasing object size, and increased with decreasing incident X-ray exposure. The increase in threshold contrasts was small when the relative incident exposure decreased from 1 to 1/4, and was large when incident exposure was decreased further.
distributed computing, Web information systems engineering, software engineering, computer graphics, and Dashboard, NREL Energy Story visualization, Green Button data integration, as well as a large number of Web of an R&D 100 Award. Prior to joining NREL, Alex worked as a system administrator, Web developer
Effects of Convective Transport on the Budget of Amazonian Aerosol under Background Conditions
NASA Astrophysics Data System (ADS)
Wang, J.; Krejci, R.; Giangrande, S. E.; Kuang, C.; Barbosa, H. M.; Brito, J.; Carbone, S.; Chi, X.; Comstock, J. M.; Ditas, F.; Lavric, J. V.; Manninen, H. E.; Mei, F.; Moran, D.; Pöhlker, C.; Pöhlker, M. L.; Saturno, J.; Schmid, B.; Souza, R. A. F. D.; Springston, S. R.; Tomlinson, J. M.; Toto, T.; Walter, D.; Wimmer, D.; Smith, J. N.; Machado, L.; Artaxo, P.; Andreae, M. O.; Martin, S. T.
2016-12-01
Aerosol particles can strongly influence the radiative properties of clouds, and they represent one of the largest uncertainties in computer simulations of climate change. The large uncertainty is in large part due to a poor understanding of processes under natural conditions, which serves as the baseline to measure change against. Understanding the processes under natural conditions is critical for a reliable assessment and quantification of ongoing and future climate change. The Amazon rainforest is one of the few continental regions where aerosol particles and their precursors can be studied under near-natural conditions. Here we examine the aerosol number and CCN budget under background conditions in the Amazon basin using data collected during the Observations and Modeling of the Green Ocean Amazon (GoAmazon 2014/5) campaign, which took place from January 2014 to December 2015 near Manaus, Brazil. The aerosol size spectrum was observed at the Amazon Tall Tower Observatory (ATTO), 150 km upwind of Manaus, and its variation with convection and precipitation during the wet season is presented. Air masses arriving at the ATTO during the wet season are typically brought by the northeasterly trade winds and travel across at least 1000 km of undeveloped tropical rainforest, therefore are generally clean. Also shown are vertical profiles of aerosol observed onboard the DOE Gulfstream-1 research aircraft. The impact of convective transport on the budget of boundary layer aerosol and CCN under the background conditions is discussed.
Advanced technologies in the ASI MLRO towards a new generation laser ranging system
NASA Technical Reports Server (NTRS)
Varghese, Thomas; Bianco, Giuseppe
1994-01-01
Matera Laser Ranging Observatory (MLRO) is a high performance, highly automated optical and astronomical observatory currently under design and development by AlliedSignal for the Italian Space Agency (ASI). It is projected to become operational at the Centro Geodesia Spaziale in Matera, Italy, in 1997. MLRO, based on a 1.5-meter astronomical quality telescope, will perform ranging to spacecraft in earthbound orbits, lunar reflectors, and specially equipped deep space missions. The primary emphasis during design is to incorporate state-of-the-art technologies to produce an intelligent, automated, high accuracy ranging system that will mimic the characteristic features of a fifth generation laser ranging system. The telescope has multiple ports and foci to support future experiments in the areas of laser communications, lidar, astrometry, etc. The key features providing state-of-the-art ranging performance include: a diode-pumped picosecond (50 ps) laser, high speed (3-5 GHz) optoelectronic detection and signal processing, and a high accuracy (6 ps) high resolution (less than 2 ps) time measurement capability. The above combination of technologies is expected to yield millimeter laser ranging precision and accuracy on targets up to 300,000 km, surpassing the best operational instrument performance to date by a factor of five or more. Distributed processing and control using a state-of-the-art computing environment provides the framework for efficient operation, system optimization, and diagnostics. A computationally intelligent environment permits optimal planning, scheduling, tracking, and data processing. It also supports remote access, monitor, and control for joint experiments with other observatories.
Supernova 2011at = PSN J09285756-1448206 in MCG -02-24-27
NASA Astrophysics Data System (ADS)
Waagen, Elizabeth O.
2011-03-01
Announces the discovery of SN 2011at = PSN J09285756-1448206 in MCG -02-24-27 by Lou Cox, Jack Newton, and Tim Puckett (Ellijay, GA, in the course of the Puckett Observatory Supernova Search) on 2011 March 10.214 UT at unfiltered CCD magnitude 14.5. Spectra obtained March 11.81 UT with the Swift satellite (+UVOT) by F. Bufano (Istituto Nazionale di Astrofisica (INAF), Osservatorio Astronomico di Catania), S. Benetti (INAF, Osservatorio Astronomico di Padova), and A. Pastorello (Queen's University, Belfast, et al.); and on March 12 UT with the F. L. Whipple Observatory 1.5-m telescope (+FAST) by M. Calkins (reported by G. H. Marion, Harvard-Smithsonian Center for Astrophysics (CfA), on behalf of the CfA Supernova Group) show SN 2011at to be a type-Ia supernova a few days before/around maximum. The object was designated PSN J09285756-1448206 when posted on the Central Bureau's Transient Objects Confirmation Page (TOCP) webpage. Initially announced in CBET 2676 (Daniel W. ! E. Green, ed.). Finder charts with sequence may be created using the AAVSO Variable Star Plotter (http://www.aavso.org/vsp). Observations should be submitted to the AAVSO International Database. See full Alert Notice for more details.
Kepler's Supernova Remnant: A View from Chandra X-Ray Observatory
NASA Technical Reports Server (NTRS)
2004-01-01
[figure removed for brevity, see original site]
[figure removed for brevity, see original site] Figure 1 Each top panel in the composite above shows the entire remnant. Each color in the composite represents a different region of the electromagnetic spectrum, from X-rays to infrared light. The X-ray and infrared data cannot be seen with the human eye. Astronomers have color-coded those data so they can be seen in these images. The bottom panels are close-up views of the remnant. In the bottom, center image, Hubble sees fine details in the brightest, densest areas of gas. The region seen in these images is outlined in the top, center panel. The images indicate that the bubble of gas that makes up the supernova remnant appears different in various types of light. Chandra reveals the hottest gas [colored blue and colored green], which radiates in X-rays. The blue color represents the higher-energy gas; the green, the lower-energy gas. Hubble shows the brightest, densest gas [colored yellow], which appears in visible light. Spitzer unveils heated dust [colored red], which radiates in infrared light.A Computer Program for the Computation of Running Gear Temperatures Using Green's Function
NASA Technical Reports Server (NTRS)
Koshigoe, S.; Murdock, J. W.; Akin, L. S.; Townsend, D. P.
1996-01-01
A new technique has been developed to study two dimensional heat transfer problems in gears. This technique consists of transforming the heat equation into a line integral equation with the use of Green's theorem. The equation is then expressed in terms of eigenfunctions that satisfy the Helmholtz equation, and their corresponding eigenvalues for an arbitrarily shaped region of interest. The eigenfunction are obtalned by solving an intergral equation. Once the eigenfunctions are found, the temperature is expanded in terms of the eigenfunctions with unknown time dependent coefficients that can be solved by using Runge Kutta methods. The time integration is extremely efficient. Therefore, any changes in the time dependent coefficients or source terms in the boundary conditions do not impose a great computational burden on the user. The method is demonstrated by applying it to a sample gear tooth. Temperature histories at representative surface locatons are given.
Mapping urban green open space in Bontang city using QGIS and cloud computing
NASA Astrophysics Data System (ADS)
Agus, F.; Ramadiani; Silalahi, W.; Armanda, A.; Kusnandar
2018-04-01
Digital mapping techniques are available freely and openly so that map-based application development is easier, faster and cheaper. A rapid development of Cloud Computing Geographic Information System makes this system can help the needs of the community for the provision of geospatial information online. The presence of urban Green Open Space (GOS) provide great benefits as an oxygen supplier, carbon-binding agent and can contribute to providing comfort and beauty of city life. This study aims to propose a platform application of GIS Cloud Computing (CC) of Bontang City GOS mapping. The GIS-CC platform uses the basic map available that’s free and open source. The research used survey method to collect GOS data obtained from Bontang City Government, while application developing works Quantum GIS-CC. The result section describes the existence of GOS Bontang City and the design of GOS mapping application.
The University of Florida's next-generation cryogenic infrared focal plane array controller system
NASA Astrophysics Data System (ADS)
Raines, Steven N.; Boreman, Glenn D.; Eikenberry, Stephen S.; Bandyopadhyay, Reba M.; Quijano, Ismael
2008-07-01
The Infrared Instrumentation Group at the University of Florida has substantial experience building IR focal plane array (FPA) controllers and seamlessly integrating them into the instruments that it builds for 8-meter class observatories, including writing device drivers for UNIX-based computer systems. We report on a design study to investigate implementing an ASIC from Teledyne Imaging Systems (TIS) into our IR FPA controller while simultaneously replacing TIS's interface card with one that eliminates the requirement for a Windows-OS computer within the instrument's control system.
Design and Implementation of the PALM-3000 Real-Time Control System
NASA Technical Reports Server (NTRS)
Truong, Tuan N.; Bouchez, Antonin H.; Burruss, Rick S.; Dekany, Richard G.; Guiwits, Stephen R.; Roberts, Jennifer E.; Shelton, Jean C.; Troy, Mitchell
2012-01-01
This paper reflects, from a computational perspective, on the experience gathered in designing and implementing realtime control of the PALM-3000 adaptive optics system currently in operation at the Palomar Observatory. We review the algorithms that serve as functional requirements driving the architecture developed, and describe key design issues and solutions that contributed to the system's low compute-latency. Additionally, we describe an implementation of dense matrix-vector-multiplication for wavefront reconstruction that exceeds 95% of the maximum sustained achievable bandwidth on NVIDIA Geforce 8800GTX GPU.
Monitoring Start of Season in Alaska
NASA Astrophysics Data System (ADS)
Robin, J.; Dubayah, R.; Sparrow, E.; Levine, E.
2006-12-01
In biomes that have distinct winter seasons, start of spring phenological events, specifically timing of budburst and green-up of leaves, coincides with transpiration. Seasons leave annual signatures that reflect the dynamic nature of the hydrologic cycle and link the different spheres of the Earth system. This paper evaluates whether continuity between AVHRR and MODIS normalized difference vegetation index (NDVI) is achievable for monitoring land surface phenology, specifically start of season (SOS), in Alaska. Additionally, two thresholds, one based on NDVI and the other on accumulated growing degree-days (GDD), are compared to determine which most accurately predicts SOS for Fairbanks. Ratio of maximum greenness at SOS was computed from biweekly AVHRR and MODIS composites for 2001 through 2004 for Anchorage and Fairbanks regions. SOS dates were determined from annual green-up observations made by GLOBE students. Results showed that different processing as well as spectral characteristics of each sensor restrict continuity between the two datasets. MODIS values were consistently higher and had less inter-annual variability during the height of the growing season than corresponding AVHRR values. Furthermore, a threshold of 131-175 accumulated GDD was a better predictor of SOS for Fairbanks than a NDVI threshold applied to AVHRR and MODIS datasets. The NDVI threshold was developed from biweekly AVHRR composites from 1982 through 2004 and corresponding annual green-up observations at University of Alaska-Fairbanks (UAF). The GDD threshold was developed from 20+ years of historic daily mean air temperature data and the same green-up observations. SOS dates computed with the GDD threshold most closely resembled actual green-up dates observed by GLOBE students and UAF researchers. Overall, biweekly composites and effects of clouds, snow, and conifers limit the ability of NDVI to monitor phenological changes in Alaska.
NASA Astrophysics Data System (ADS)
Yan, Jiawei; Ke, Youqi
2016-07-01
Electron transport properties of nanoelectronics can be significantly influenced by the inevitable and randomly distributed impurities/defects. For theoretical simulation of disordered nanoscale electronics, one is interested in both the configurationally averaged transport property and its statistical fluctuation that tells device-to-device variability induced by disorder. However, due to the lack of an effective method to do disorder averaging under the nonequilibrium condition, the important effects of disorders on electron transport remain largely unexplored or poorly understood. In this work, we report a general formalism of Green's function based nonequilibrium effective medium theory to calculate the disordered nanoelectronics. In this method, based on a generalized coherent potential approximation for the Keldysh nonequilibrium Green's function, we developed a generalized nonequilibrium vertex correction method to calculate the average of a two-Keldysh-Green's-function correlator. We obtain nine nonequilibrium vertex correction terms, as a complete family, to express the average of any two-Green's-function correlator and find they can be solved by a set of linear equations. As an important result, the averaged nonequilibrium density matrix, averaged current, disorder-induced current fluctuation, and averaged shot noise, which involve different two-Green's-function correlators, can all be derived and computed in an effective and unified way. To test the general applicability of this method, we applied it to compute the transmission coefficient and its fluctuation with a square-lattice tight-binding model and compared with the exact results and other previously proposed approximations. Our results show very good agreement with the exact results for a wide range of disorder concentrations and energies. In addition, to incorporate with density functional theory to realize first-principles quantum transport simulation, we have also derived a general form of conditionally averaged nonequilibrium Green's function for multicomponent disorders.
[Assessment of the potential for urban facade greening in Xinjiekou District, Nanjing, China.
Shi, Bao Gang; Yin, Hai Wei; Kong, Fan Hua
2018-05-01
Green facade is an important strategy to improve the urban eco-environment and reduce the negative effects of human activities in central districts of cities which are land-scarce and lack green spaces. We first summarized the limiting factors for the construction of green facades locally and internationally. Then, we used the Xinjiekou District of Nanjing City in China as a case study area, and selected the wind environment, solar environment, and physical build environment that might impact the potential development of green facades as key factors to quantitatively analyze singlely by geographic information systems (GIS) and computational fluid dynamics (CFD). Finally, the potential area to develop green facades was assessed through a multi-factor overlay analysis. The results showed that 17726 m 2 of wall spaces in the Xinjiekou District had a high potential for facade greening, accounting for 30.8% of all exterior wall space under a height of 12 m and 17.3% of the entire study area. Sunlight was a key limiting factor in determining whether a green facade should be developed. Irrigation was identified as another important factor that might strongly affect the growth of vertical vegetation in urban environment. The spatial distribution of walls suitable for facade greening was uneven, with an "inner-high and south-high" spatial pattern. Our results would help to guide the design and development of green facades in Xinjiekou, and also provide a reference for planning and utilizing green wall space projects in other built and dense urban areas.
A new mix of power for the ESO installations in Chile: greener, more reliable, cheaper
NASA Astrophysics Data System (ADS)
Filippi, G.; Tamai, R.; Kalaitzoglou, D.; Wild, W.; Delorme, A.; Rioseco, D.
2016-07-01
The highest sky quality demands for astronomical research impose to locate observatories often in areas not easily reached by the existing power infrastructures. At the same time, availability and cost of power is a primary factor for sustainable operations. Power may also be a potential source for CO2 pollution. As part of its green initiatives, ESO is in the process of replacing the power sources for its own, La Silla and Paranal-Armazones, and shared, ALMA, installations in Chile in order to provide them with more reliable, affordable, and smaller CO2 footprint power solutions. The connectivity to the Chilean interconnected power systems (grid) which is to extensively use Non-Conventional Renewable Energy (NCRE) as well as the use of less polluting fuels wherever self-generation cannot be avoided are key building blocks for the solutions selected for every site. In addition, considerations such as the environmental impact and - if required - the partnership with other entities have also to be taken into account. After years of preparatory work to which the Chilean Authorities provided great help and support, ESO has now launched an articulated program to upgrade the existing agreements/facilities in i) the La Silla Observatory, from free to regulated grid client status due to an agreement with a Solar Farm private initiative, in ii) the Paranal-Armazones Observatory, from local generation using liquefied petroleum gas (LPG) to connection to the grid which is to extensively use NCRE, and last but not least, in iii) the ALMA Observatory where ESO participates together with North American and East Asian partners, from replacing the LPG as fuel for the turbine local generation system with the use of less polluting natural gas (NG) supplied by a pipe connection to eliminate the pollution caused by the LPG trucks (currently 1 LPG truck from the VIII region, Bio Bio, to the II region, ALMA and back every day, for a total of 3000km). The technologies used and the status of completion of the different projects, as well as the expected benefits are discussed in this paper.
NASA Astrophysics Data System (ADS)
Resdiansyah; O. K Rahmat, R. A.; Ismail, A.
2018-03-01
Green transportation refers to a sustainable transport that gives the least impact in terms of social and environmental but at the same time is able to supply energy sources globally that includes non-motorized transport strategies deployment to promote healthy lifestyles, also known as Mobility Management Scheme (MMS). As construction of road infrastructure cannot help solve the problem of congestion, past research has shown that MMS is an effective measure to mitigate congestion and to achieve green transportation. MMS consists of different strategies and policies that subdivided into categories according to how they are able to influence travel behaviour. Appropriate selection of mobility strategies will ensure its effectiveness in mitigating congestion problems. Nevertheless, determining appropriate strategies requires human expert and depends on a number of success factors. This research has successfully developed a computer clone system based on human expert, called E-MMS. The process of knowledge acquisition for MMS strategies and the next following process to selection of strategy has been encode in a knowledge-based system using a shell expert system. The newly developed computer cloning system was successfully verified, validated and evaluated (VV&E) by comparing the result output with the real transportation expert recommendation in which the findings suggested Introduction
Computer Exercises in Meteorology.
ERIC Educational Resources Information Center
Trapasso, L. Michael; Conner, Glen; Stallins, Keith
Beginning with Western Kentucky University's (Bowling Green) fall 1999 semester, exercises required for the geography and meteorology course used computers for learning. This course enrolls about 250 students per year, most of whom choose it to fulfill a general education requirement. Of the 185 geography majors, it is required for those who…
Modeling Regional Seismic Waves
1992-06-29
the computation of the Green’s functions is rather time comsuming . they arc Computed for each of the fundamental faults, at I1(H) km intervals from 21...this record was very, small. Station GEO displays similar behavior in that the overall features of the waveform are matched, but fit in detail is not
ERIC Educational Resources Information Center
Nelson, Jacqueline M.
2011-01-01
In looking at the interesting shapes and sizes of old computer parts, creating robots quickly came to the author's mind. In this article, she describes how computer parts can be used creatively. Students will surely enjoy creating their very own robots while learning about the importance of recycling in the society. (Contains 1 online resource.)
NASA Marshall Space Flight Center Solar Observatory Report, July to December 1992
NASA Technical Reports Server (NTRS)
Smith, J. E.
1993-01-01
This report provides a description of the NASA Marshall Space Flight Center's Solar Vector Magnetograph Facility and gives a summary of its observations and data reduction during July-December 1992. The systems that make up the facility are a magnetograph telescope, an H-alpha telescope, a Questar telescope, and a computer code.
NASA Marshall Space Flight Center Solar Observatory report, January - June 1992
NASA Technical Reports Server (NTRS)
Smith, James E.
1992-01-01
This report provides a description of the NASA Marshall Space Flight Center's Solar Vector Magnetograph Facility and gives a summary of its observations and data reduction during Jan. to Jun. 1992. The systems that make up the facility are a magnetograph telescope, and H-alpha telescope, a Questar telescope, and a computer code.
Science of Security Lablet - Scalability and Usability
2014-12-16
mobile computing [19]. However, the high-level infrastructure design and our own implementation (both described throughout this paper) can easily...critical and infrastructural systems demands high levels of sophistication in the technical aspects of cybersecurity, software and hardware design...Forget, S. Komanduri, Alessandro Acquisti, Nicolas Christin, Lorrie Cranor, Rahul Telang. "Security Behavior Observatory: Infrastructure for Long-term
Overcomplete compact representation of two-particle Green's functions
NASA Astrophysics Data System (ADS)
Shinaoka, Hiroshi; Otsuki, Junya; Haule, Kristjan; Wallerberger, Markus; Gull, Emanuel; Yoshimi, Kazuyoshi; Ohzeki, Masayuki
2018-05-01
Two-particle Green's functions and the vertex functions play a critical role in theoretical frameworks for describing strongly correlated electron systems. However, numerical calculations at the two-particle level often suffer from large computation time and massive memory consumption. We derive a general expansion formula for the two-particle Green's functions in terms of an overcomplete representation based on the recently proposed "intermediate representation" basis. The expansion formula is obtained by decomposing the spectral representation of the two-particle Green's function. We demonstrate that the expansion coefficients decay exponentially, while all high-frequency and long-tail structures in the Matsubara-frequency domain are retained. This representation therefore enables efficient treatment of two-particle quantities and opens a route to the application of modern many-body theories to realistic strongly correlated electron systems.
Efficiency optimization of a fast Poisson solver in beam dynamics simulation
NASA Astrophysics Data System (ADS)
Zheng, Dawei; Pöplau, Gisela; van Rienen, Ursula
2016-01-01
Calculating the solution of Poisson's equation relating to space charge force is still the major time consumption in beam dynamics simulations and calls for further improvement. In this paper, we summarize a classical fast Poisson solver in beam dynamics simulations: the integrated Green's function method. We introduce three optimization steps of the classical Poisson solver routine: using the reduced integrated Green's function instead of the integrated Green's function; using the discrete cosine transform instead of discrete Fourier transform for the Green's function; using a novel fast convolution routine instead of an explicitly zero-padded convolution. The new Poisson solver routine preserves the advantages of fast computation and high accuracy. This provides a fast routine for high performance calculation of the space charge effect in accelerators.
Banzato, Tommaso; Selleri, Paolo; Veladiano, Irene A; Martin, Andrea; Zanetti, Emanuele; Zotti, Alessandro
2012-05-11
Radiology and computed tomography are the most commonly available diagnostic tools for the diagnosis of pathologies affecting the head and skull in veterinary practice. Nevertheless, accurate interpretation of radiographic and CT studies requires a thorough knowledge of the gross and the cross-sectional anatomy. Despite the increasing success of reptiles as pets, only a few reports over their normal imaging features are currently available. The aim of this study is to describe the normal cadaveric, radiographic and computed tomographic features of the heads of the green iguana, tegu and bearded dragon. 6 adult green iguanas, 4 tegus, 3 bearded dragons, and, the adult cadavers of: 4 green iguana, 4 tegu, 4 bearded dragon were included in the study. 2 cadavers were dissected following a stratigraphic approach and 2 cadavers were cross-sectioned for each species. These latter specimens were stored in a freezer (-20°C) until completely frozen. Transversal sections at 5 mm intervals were obtained by means of an electric band-saw. Each section was cleaned and photographed on both sides. Radiographs of the head of each subject were obtained. Pre- and post- contrast computed tomographic studies of the head were performed on all the live animals. CT images were displayed in both bone and soft tissue windows. Individual anatomic structures were first recognised and labelled on the anatomic images and then matched on radiographs and CT images. Radiographic and CT images of the skull provided good detail of the bony structures in all species. In CT contrast medium injection enabled good detail of the soft tissues to be obtained in the iguana whereas only the eye was clearly distinguishable from the remaining soft tissues in both the tegu and the bearded dragon. The results provide an atlas of the normal anatomical and in vivo radiographic and computed tomographic features of the heads of lizards, and this may be useful in interpreting any imaging modality involving these species.
2012-01-01
Background Radiology and computed tomography are the most commonly available diagnostic tools for the diagnosis of pathologies affecting the head and skull in veterinary practice. Nevertheless, accurate interpretation of radiographic and CT studies requires a thorough knowledge of the gross and the cross-sectional anatomy. Despite the increasing success of reptiles as pets, only a few reports over their normal imaging features are currently available. The aim of this study is to describe the normal cadaveric, radiographic and computed tomographic features of the heads of the green iguana, tegu and bearded dragon. Results 6 adult green iguanas, 4 tegus, 3 bearded dragons, and, the adult cadavers of : 4 green iguana, 4 tegu, 4 bearded dragon were included in the study. 2 cadavers were dissected following a stratigraphic approach and 2 cadavers were cross-sectioned for each species. These latter specimens were stored in a freezer (−20°C) until completely frozen. Transversal sections at 5 mm intervals were obtained by means of an electric band-saw. Each section was cleaned and photographed on both sides. Radiographs of the head of each subject were obtained. Pre- and post- contrast computed tomographic studies of the head were performed on all the live animals. CT images were displayed in both bone and soft tissue windows. Individual anatomic structures were first recognised and labelled on the anatomic images and then matched on radiographs and CT images. Radiographic and CT images of the skull provided good detail of the bony structures in all species. In CT contrast medium injection enabled good detail of the soft tissues to be obtained in the iguana whereas only the eye was clearly distinguishable from the remaining soft tissues in both the tegu and the bearded dragon. Conclusions The results provide an atlas of the normal anatomical and in vivo radiographic and computed tomographic features of the heads of lizards, and this may be useful in interpreting any imaging modality involving these species. PMID:22578088
NASA Astrophysics Data System (ADS)
Matos, Catarina; Silveira, Graça; Custódio, Susana; Domingues, Ana; Dias, Nuno; Fonseca, João F. B.; Matias, Luís; Krueger, Frank; Carrilho, Fernando
2014-05-01
Noise cross-correlations are now widely used to extract Green functions between station pairs. But, do all the cross-correlations routinely computed produce successful Green Functions? What is the relationship between noise recorded in a couple of stations and the cross-correlation between them? During the last decade, we have been involved in the deployment of several temporary dense broadband (BB) networks within the scope of both national projects and international collaborations. From 2000 to 2002, a pool of 8 BB stations continuously operated in the Azores in the scope of the Memorandum of Understanding COSEA (COordinated Seismic Experiment in the Azores). Thanks to the Project WILAS (West Iberia Lithosphere and Astenosphere Structure, PTDC/CTE-GIX/097946/2008) we temporarily increased the number of BB deployed in mainland Portugal to more than 50 (permanent + temporary) during the period 2010 - 2012. In 2011/12 a temporary pool of 12 seismometers continuously recorded BB data in the Madeira archipelago, as part of the DOCTAR (Deep Ocean Test Array Experiment) project. Project CV-PLUME (Investigation on the geometry and deep signature of the Cape Verde mantle plume, PTDC/CTE-GIN/64330/2006) covered the archipelago of Cape Verde, North Atlantic, with 40 temporary BB stations in 2007/08. Project MOZART (Mozambique African Rift Tomography, PTDC/CTE-GIX/103249/2008), covered Mozambique, East Africa, with 30 temporary BB stations in the period 2011 - 2013. These networks, located in very distinct geographical and tectonic environments, offer an interesting opportunity to study seasonal and spatial variations of noise sources and their impact on Empirical Green functions computed from noise cross-correlation. Seismic noise recorded at different seismic stations is evaluated by computation of the probability density functions of power spectral density (PSD) of continuous data. To assess seasonal variations of ambient noise sources in frequency content, time-series of PSD at different frequency bands have been computed. The influence of the spatial and seasonal variation is evaluated by analysis of the one-day length cross-correlations, stacked with a 30-day moving window and with an overlap of 30 days. To inspect the effects of frequency content variations, 30-day cross-correlograms have also been computed at different frequency bands. This work is supported by project QuakeLoc-PT (PTDC/GEO-FIQ/3522/2012) and a contribution to project AQUAREL (PTDC/CTE-GIX/116819/2010).
The Montage architecture for grid-enabled science processing of large, distributed datasets
NASA Technical Reports Server (NTRS)
Jacob, Joseph C.; Katz, Daniel S .; Prince, Thomas; Berriman, Bruce G.; Good, John C.; Laity, Anastasia C.; Deelman, Ewa; Singh, Gurmeet; Su, Mei-Hui
2004-01-01
Montage is an Earth Science Technology Office (ESTO) Computational Technologies (CT) Round III Grand Challenge investigation to deploy a portable, compute-intensive, custom astronomical image mosaicking service for the National Virtual Observatory (NVO). Although Montage is developing a compute- and data-intensive service for the astronomy community, we are also helping to address a problem that spans both Earth and Space science, namely how to efficiently access and process multi-terabyte, distributed datasets. In both communities, the datasets are massive, and are stored in distributed archives that are, in most cases, remote from the available Computational resources. Therefore, state of the art computational grid technologies are a key element of the Montage portal architecture. This paper describes the aspects of the Montage design that are applicable to both the Earth and Space science communities.
LORAN-C data reduction at the US Naval Observatory
NASA Technical Reports Server (NTRS)
Chadsey, Harold
1992-01-01
As part of its mission and in cooperation with the U.S. Coast Guard, the U.S. Naval Observatory (USNO) monitors and reports the timing of the LORAN-C chains. The procedures for monitoring and processing the reported values have evolved with advances in monitoring equipment, computer interfaces and PCs. This paper discusses the current standardized procedures used by USNO to sort the raw data according to Group Repetition Interval (GRI) rate, to fit and smooth the data points, and, for chains remotely monitored, to tie the values to the USNO Master Clock. The results of these procedures are the LORAN time of transmission values, as references to UTC(USNO) (Universal Coordinated Time) for all LORAN chains. This information is available to users via USNO publications and the USNO Automated Data Service (ADS).
Laser Guide Star Based Astrophysics at Lick Observatory
DOE Office of Scientific and Technical Information (OSTI.GOV)
Max, C; Gavel, D.; Friedman, H.
2000-03-10
The resolution of ground-based telescopes is typically limited to {approx}1 second of arc because of the blurring effects of atmospheric turbulence. Adaptive optics (AO) technology senses and corrects for the optical distortions due to turbulence hundreds of times per second using high-speed sensors, computers, deformable mirror, and laser technology. The goal of this project is to make AO systems widely useful astronomical tools providing resolutions up to an order of magnitude better than current, ground-based telescopes. Astronomers at the University of California Lick Observatory at Mt. Hamilton now routinely use the LLNL developed AO system for high resolution imaging ofmore » astrophysical objects. We report here on the instrument development progress and on the science observations made with this system during this 3-year ERI project.« less
The Virtual Earth-Solar Observatory of the SCiESMEX
NASA Astrophysics Data System (ADS)
De la Luz, V.; Gonzalez-Esparza, A.; Cifuentes-Nava, G.
2015-12-01
The Mexican Space Weather Service (SCiESMEX, http://www.sciesmex.unam.mx) started operations in October 2014. The project includes the Virtual Earth-Solar Observatory (VESO, http://www.veso.unam.mx). The VESO is a improved project wich objetive is integrate the space weather instrumentation network from the National Autonomous University of Mexico (UNAM). The network includes the Mexican Array Radiotelescope (MEXART), the Callisto receptor (MEXART), a Neutron Telescope, a Cosmic Ray Telescope. the Schumann Antenna, the National Magnetic Service, and the mexican GPS network (TlalocNet). The VESO facility is located at the Geophysics Institute campus Michoacan (UNAM). We offer the service of data store, real-time data, and quasi real-time data. The hardware of VESO includes a High Performance Computer (HPC) dedicated specially to big data storage.
2013-01-01
This study examines the association between objectively measured access to green space, frequency of green space use, physical activity, and the probability of being overweight or obese in the city of Bristol, England. Data from the Bristol Quality of Life in your Neighbourhood survey for 6,821 adults were combined with a comprehensive GIS database of neighbourhood and green space characteristics.. A range of green space accessibility measures were computed. Associations between accessibility and the odds of respondents achieving a recommended 30 minutes or more of moderate activity five times a week, or being overweight or obese, were examined using logistic regression. Results showed that the reported frequency of green space use declined with increasing distance. The study also found that respondents living closest to the type of green space classified as a Formal park were more likely to achieve the physical activity recommendation and less likely to be overweight or obese. The association with physical activity, but not with overweight or obesity, remained after adjustment for respondent characteristics, area deprivation, and a range of characteristics of the neighbourhood environment. The findings suggest that the provision of good access to green spaces in urban areas may help promote population physical activity. PMID:20060635
The Green Bank Telescope: Transformational Science for the Next Decade.
NASA Astrophysics Data System (ADS)
Wootten, Al; GBO Staff
2018-01-01
The Robert C Byrd Green Bank Telescope has met its design goal of providing high-quality observations at 115 GHz. The accurate small beam of the telescope at high frequencies is leveraged by deployment of multi beam receivers. An overview is presented. Observers now have access to the new, 16-pixel, 3-mm Argus receiver, which is providing high-dynamic range images over wide fields for the multitude of spectral lines between 85 and 115 GHz. The successful performance of Argus, and its modular design, demonstrates that receivers with many more pixels could be built for the GBT. A 12 x 12 array of the Argus design would have mapping speeds about nine times faster than Argus without suffering any degradation in performance for the outer pixels in the array. The Observatory plans to build the next-generation Argus instrument (Argus+) with 144-pixels, a footprint 5'x5', and 7" resolution at 110 GHz. The project will be a collaboration between the Green Bank Observatory and university groups, who will supply key components. The key science drivers for Argus+ are studies of molecular filaments in the Milky Way, studies of molecular clouds in nearby galaxies, and the observations of rapidly evolving solar system objects. Observers also have access to MUSTANG-2, a 223-feedhorn bolometer camera which was commissioned on the GBT in spring 2016, and was offered for observations on a shared risk basis, in collaboration with the instrument team, in the 2018A GBO proposal call. Several features distinguish it from its predecessor, MUSTANG: A new, microstrip-coupled detector design yields higher sensitivity and less susceptibility to environmental microphonics. Detectors are feedhorn coupled, with the sum of two linear polarizations measured by a single TES per feed. The instantaneous field of view is 4 arcminutes (vs 42 arcseconds for MUSTANG) The receiver design incorporates a tilted refrigerator and receiver rotator, resulting in much lower dependence of cooling performance on telescope elevation. The detector readout is the first astronomical use of microwave resonators to multiplex TES bolometers. MUSTANG-2 has been developed by a collaboration including the University of Pennsylvania, NIST, NRAO, the University of Michigan, and Cardiff University. A 7-pixel K-band Feed Array covering 18-28 GHz with Dual polarization feeds and a noise temperature < 40-50 K has been available for several years. The array offers an instantaneous bandwidth/beam of 1.8 GHz. Future upgrade concepts under study envision increasing the number of beams by an order of magnitude.
NASA Astrophysics Data System (ADS)
Siebert, Stefan; Döll, Petra
2010-04-01
SummaryCrop production requires large amounts of green and blue water. We developed the new global crop water model GCWM to compute consumptive water use (evapotranspiration) and virtual water content (evapotranspiration per harvested biomass) of crops at a spatial resolution of 5' by 5', distinguishing 26 crop classes, and blue versus green water. GCWM is based on the global land use data set MIRCA2000 that provides monthly growing areas for 26 crop classes under rainfed and irrigated conditions for the period 1998-2002 and represents multi-cropping. By computing daily soil water balances, GCWM determines evapotranspiration of blue and green water for each crop and grid cell. Cell-specific crop production under both rainfed and irrigated conditions is computed by downscaling average crop yields reported for 402 national and sub-national statistical units, relating rainfed and irrigated crop yields reported in census statistics to simulated ratios of actual to potential crop evapotranspiration for rainfed crops. By restricting water use of irrigated crops to green water only, the potential production loss without any irrigation was computed. For the period 1998-2002, the global value of total crop water use was 6685 km 3 yr -1, of which blue water use was 1180 km 3 yr -1, green water use of irrigated crops was 919 km 3 yr -1 and green water use of rainfed crops was 4586 km 3 yr -1. Total crop water use was largest for rice (941 km 3 yr -1), wheat (858 km 3 yr -1) and maize (722 km 3 yr -1). The largest amounts of blue water were used for rice (307 km 3 yr -1) and wheat (208 km 3 yr -1). Blue water use as percentage of total crop water use was highest for date palms (85%), cotton (39%), citrus fruits (33%), rice (33%) and sugar beets (32%), while for cassava, oil palm and cocoa, almost no blue water was used. Average crop yield of irrigated cereals was 442 Mg km -2 while average yield of rainfed cereals was only 266 Mg km -2. Average virtual water content of cereal crops was 1109 m 3 Mg -1 of green water and 291 m 3 Mg -1 of blue water, while average crop water productivity of cereal crops was 714 g m -3. If currently irrigated crops were not irrigated, global production of dates, rice, cotton, citrus and sugar cane would decrease by 60%, 39%, 38%, 32% and 31%, respectively. Forty-three per cent of cereal production was on irrigated land, and without irrigation, cereal production on irrigated land would decrease by 47%, corresponding to a 20% loss of total cereal production. The largest cereal production losses would occur in Northern Africa (66%) and Southern Asia (45%) while losses would be very low for Northern Europe (0.001%), Western Europe (1.2%), Eastern Europe (1.5%) and Middle Africa (1.6%). Uncertainties and limitations are discussed in the manuscript, and a comparison of GCWM results to statistics or results of other studies shows good agreement at the regional scale, but larger differences for specific countries.
The mere green effect: An fMRI study of pro-environmental advertisements.
Vezich, I Stephanie; Gunter, Benjamin C; Lieberman, Matthew D
2017-08-01
Self-report evidence suggests that consumers prefer green products (i.e., pro-environmental) to standard products, but this is not reflected in purchase behaviors. To understand this disconnect, we exposed participants in a magnetic resonance imaging (MRI) scanner to green and standard ads. After viewing each ad, participants rated liking and perceived sustainability. Ratings were more favorable for green ads than for control ads, but the functional MRI data suggested an opposite pattern-participants showed greater activation in regions associated with personal value and reward (ventromedial prefrontal cortex and ventral striatum) in response to control ads relative to green ads. In addition, participants showed greater activity in these regions to the extent that they reported liking control ads, but there was no such trend for green ads. In line with a neuroeconomic account, we suggest that activity in these regions may be indexing a value signal computed during message exposure that may influence downstream purchase decisions, in contrast to self-reported evaluations that may reflect social desirability concerns absent at the point of purchase.
NASA X-Ray Observatory Completes Tests Under Harsh Simulated Space Conditions
NASA Astrophysics Data System (ADS)
1998-07-01
NASA's most powerful X-ray observatory has successfully completed a month-long series of tests in the extreme heat, cold, and airless conditions it will encounter in space during its five-year mission to shed new light on some of the darkest mysteries of the universe. The Advanced X-ray Astrophysics Facility was put through the rigorous testing as it was alternately heated and cooled in a special vacuum chamber at TRW Space and Electronics Group in Redondo Beach, Calif., NASA's prime contractor for the observatory. "Successful completion of thermal vacuum testing marks a significant step in readying the observatory for launch aboard the Space Shuttle in January," said Fred Wojtalik, manager of the Observatory Projects Office at NASA's Marshall Space Flight Center in Huntsville, Ala. "The observatory is a complex, highly sophisticated, precision instrument," explained Wojtalik. "We are pleased with the outcome of the testing, and are very proud of the tremendous team of NASA and contractor technicians, engineers and scientists that came together and worked hard to meet this challenging task." Testing began in May after the observatory was raised into the 60-foot thermal vacuum chamber at TRW. Testing was completed on June 20. During the tests the Advanced X-ray Astrophysics Facility was exposed to 232 degree heat and 195 degree below zero Fahrenheit cold. During four temperature cycles, all elements of the observatory - the spacecraft, telescope, and science instruments - were checked out. Computer commands directing the observatory to perform certain functions were sent from test consoles at TRW to all Advanced X-ray Astrophysics Facility components. A team of contractor and NASA engineers and scientists monitored and evaluated the results. Commands were also sent from, and test data monitored at, the Advanced X-ray Astrophysics Facility Operations Control Center in Cambridge, Mass., as part of the test series. The observatory will be managed and controlled from the Operations Control Center after launch. "As is usually the case, we identified a few issues to be resolved before launch," said Wojtalik. "Overall, however, the observatory performed exceptionally well." The observatory test team discovered a mechanical problem with one of the primary science instruments, the Imaging Spectrometer. A door protecting the instrument did not function when commanded by test controllers. "We do these tests to check and double check every aspect of satellite operation that could affect the ultimate success of the science mission," said Craig Staresinich, TRW Advanced X-ray Astrophysics Facility program manager. "Discovering a problem now is a success. Discovering a problem later, after launch, would be a failure." A team of NASA and contractor engineers are studying the mechanical problem and developing a plan to correct it. The instrument will be sent back to its builder, Lockheed-Martin Astronautics in Denver, Colo., where it will be repaired while the rest of the observatory continues other testing. This should still allow an on-time delivery of the observatory to NASA's Kennedy Space Center, Fla., in August, where it will be readied for launch in January. With a resolving power 10 times greater than previous X-ray telescopes, the new X-ray observatory will provide scientists with views of previously invisible X-ray sources, including black holes, exploding stars and interstellar gasses. The third of NASA's Great Observatories, it will join the Compton Gamma Ray Observatory and the Hubble Space Telescope in orbit. The Advanced X-ray Astrophysics Facility program is managed by the Marshall Center for the Office of Space Science, NASA Headquarters, Washington, D.C. TRW Space & Electronics Group is assembling the observatory and doing verification testing. The Advanced X-ray Astrophysics Facility Operations Control Center is operated by the Smithsonian Astrophysical Observatory. Using glass purchased from Schott Glaswerke, Mainz, Germany, the telescope's mirrors were built by Raytheon Optical Systems Inc., Danbury, Conn. The mirrors were coated by Optical Coating Laboratory, Inc., Santa Rosa, Calif., and assembled by EastmanKodak Co., Rochester, N.Y. The Advanced X-ray Astrophysics Facility Charge-Coupled Device Imaging Spectrometer was developed by Pennsylvania State University, University Park, Pa., and the Massachusetts Institute of Technology (MIT), Cambridge. One diffraction grating was developed by MIT, the other by the Space Research Organization Netherlands, Utrecht, Netherlands, in collaboration with the Max Planck Institute, Garching, Germany. The High Resolution Camera was built by the Smithsonian Astrophysical Observatory. Ball Aerospace & Technologies Corporation of Boulder, Colo., developed the aspect camera and the Science Instrument Module. Note to editors: Digital images to accompany this release are available via the World Wide Web at the following URL: http://chandra.harvard.edu/press/images.html
NASA Astrophysics Data System (ADS)
Ramirez, P.; Mattmann, C. A.; Painter, T. H.; Seidel, F. C.; Trangsrud, A.; Hart, A. F.; Goodale, C. E.; Boardman, J. W.; Heneghan, C.; Verma, R.; Khudikyan, S.; Boustani, M.; Zimdars, P. A.; Horn, J.; Neely, S.
2013-12-01
The JPL Airborne Snow Observatory (ASO) must process 100s of GB of raw data to 100s of Terabytes of derived data in 24 hour Near Real Time (NRT) latency in a geographically distributed mobile compute and data-intensive processing setting. ASO provides meaningful information to water resource managers in the Western US letting them know how much water to maintain; or release, and what the prospectus of the current snow season is in the Sierra Nevadas. Providing decision support products processed from airborne data in a 24 hour timeframe is an emergent field and required the team to develop a novel solution as this process is typically done over months. We've constructed a system that combines Apache OODT; with Apache Tika; with the Interactive Data Analysis (IDL)/ENVI programming environment to rapidly and unobtrusively generate, distribute and archive ASO data as soon as the plane lands near Mammoth Lakes, CA. Our system is flexible, underwent several redeployments and reconfigurations, and delivered this critical information to stakeholders during the recent "Snow On" campaign March 2013 - June 2013. This talk will take you through a day in the life of the compute team from data acquisition, delivery, processing, and dissemination. Within this context, we will discuss the architecture of ASO; the open source software we used; the data we stored; and how it was delivered to its users. Moreover we will discuss the logistics, system engineering, and staffing that went into the developing, deployment, and operation of the mobile compute system.
Finite-fault source inversion using adjoint methods in 3D heterogeneous media
NASA Astrophysics Data System (ADS)
Somala, Surendra Nadh; Ampuero, Jean-Paul; Lapusta, Nadia
2018-04-01
Accounting for lateral heterogeneities in the 3D velocity structure of the crust is known to improve earthquake source inversion, compared to results based on 1D velocity models which are routinely assumed to derive finite-fault slip models. The conventional approach to include known 3D heterogeneity in source inversion involves pre-computing 3D Green's functions, which requires a number of 3D wave propagation simulations proportional to the number of stations or to the number of fault cells. The computational cost of such an approach is prohibitive for the dense datasets that could be provided by future earthquake observation systems. Here, we propose an adjoint-based optimization technique to invert for the spatio-temporal evolution of slip velocity. The approach does not require pre-computed Green's functions. The adjoint method provides the gradient of the cost function, which is used to improve the model iteratively employing an iterative gradient-based minimization method. The adjoint approach is shown to be computationally more efficient than the conventional approach based on pre-computed Green's functions in a broad range of situations. We consider data up to 1 Hz from a Haskell source scenario (a steady pulse-like rupture) on a vertical strike-slip fault embedded in an elastic 3D heterogeneous velocity model. The velocity model comprises a uniform background and a 3D stochastic perturbation with the von Karman correlation function. Source inversions based on the 3D velocity model are performed for two different station configurations, a dense and a sparse network with 1 km and 20 km station spacing, respectively. These reference inversions show that our inversion scheme adequately retrieves the rise time when the velocity model is exactly known, and illustrates how dense coverage improves the inference of peak slip velocities. We investigate the effects of uncertainties in the velocity model by performing source inversions based on an incorrect, homogeneous velocity model. We find that, for velocity uncertainties that have standard deviation and correlation length typical of available 3D crustal models, the inverted sources can be severely contaminated by spurious features even if the station density is high. When data from thousand or more receivers is used in source inversions in 3D heterogeneous media, the computational cost of the method proposed in this work is at least two orders of magnitude lower than source inversion based on pre-computed Green's functions.
Finite-fault source inversion using adjoint methods in 3-D heterogeneous media
NASA Astrophysics Data System (ADS)
Somala, Surendra Nadh; Ampuero, Jean-Paul; Lapusta, Nadia
2018-07-01
Accounting for lateral heterogeneities in the 3-D velocity structure of the crust is known to improve earthquake source inversion, compared to results based on 1-D velocity models which are routinely assumed to derive finite-fault slip models. The conventional approach to include known 3-D heterogeneity in source inversion involves pre-computing 3-D Green's functions, which requires a number of 3-D wave propagation simulations proportional to the number of stations or to the number of fault cells. The computational cost of such an approach is prohibitive for the dense data sets that could be provided by future earthquake observation systems. Here, we propose an adjoint-based optimization technique to invert for the spatio-temporal evolution of slip velocity. The approach does not require pre-computed Green's functions. The adjoint method provides the gradient of the cost function, which is used to improve the model iteratively employing an iterative gradient-based minimization method. The adjoint approach is shown to be computationally more efficient than the conventional approach based on pre-computed Green's functions in a broad range of situations. We consider data up to 1 Hz from a Haskell source scenario (a steady pulse-like rupture) on a vertical strike-slip fault embedded in an elastic 3-D heterogeneous velocity model. The velocity model comprises a uniform background and a 3-D stochastic perturbation with the von Karman correlation function. Source inversions based on the 3-D velocity model are performed for two different station configurations, a dense and a sparse network with 1 and 20 km station spacing, respectively. These reference inversions show that our inversion scheme adequately retrieves the rise time when the velocity model is exactly known, and illustrates how dense coverage improves the inference of peak-slip velocities. We investigate the effects of uncertainties in the velocity model by performing source inversions based on an incorrect, homogeneous velocity model. We find that, for velocity uncertainties that have standard deviation and correlation length typical of available 3-D crustal models, the inverted sources can be severely contaminated by spurious features even if the station density is high. When data from thousand or more receivers is used in source inversions in 3-D heterogeneous media, the computational cost of the method proposed in this work is at least two orders of magnitude lower than source inversion based on pre-computed Green's functions.
Methods for Functional Connectivity Analyses
2012-12-13
motor , or hand motor function (green, red, or blue shading, respectively). Thus, this work produced the first comprehensive analysis of ECoG...Computer Engineering, University of Texas at El Paso , TX, USA 3Department of Neurology, Albany Medical College, Albany, NY, USA 4Department of Computer...Department of Health, Albany, NY, USA bDepartment of Electrical and Computer Engineering, University of Texas at El Paso , TX, USA cDepartment of Neurology
Implementing a Computer/Technology Endorsement in a Classroom Technology Master's Program.
ERIC Educational Resources Information Center
Brownell, Gregg; O'Bannon, Blanche; Brownell, Nancy
In the spring of 1998, the Master's program in Classroom Technology at Bowling Green State University (Ohio) was granted conditional approval to grant, as part of the program, the new State of Ohio Department of Education computer/technology endorsement. This paper briefly describes Ohio's change from certification to licensure, the removal of…
Green Day? An Old Mill City Leads a New Revolution in Massachusetts
ERIC Educational Resources Information Center
Brown, Robert A.
2012-01-01
The Northeast United States just experienced one of the region's worst natural disasters. Fortunately, because of the confluence of modern computing power and scientific computing methods, weather forecasting models predicted Sandy's very complicated trajectory and development with a precision that would not have been possible even a decade ago.…
Beam Dynamics Simulation Platform and Studies of Beam Breakup in Dielectric Wakefield Structures
NASA Astrophysics Data System (ADS)
Schoessow, P.; Kanareykin, A.; Jing, C.; Kustov, A.; Altmark, A.; Gai, W.
2010-11-01
A particle-Green's function beam dynamics code (BBU-3000) to study beam breakup effects is incorporated into a parallel computing framework based on the Boinc software environment, and supports both task farming on a heterogeneous cluster and local grid computing. User access to the platform is through a web browser.
It Is Worth Thoroughly Looking at the Computer Display
ERIC Educational Resources Information Center
Kraftmakher, Yaakov
2009-01-01
Two useful observations are possible when thoroughly looking at the cathode-ray display of a computer. First, the structure of a color image is seen with a moderate magnification. Second, the decay of different phosphors corresponding to the red, green, and blue primary colors is observable with a photodiode and oscilloscope.
Computer Software for Forestry Technology Curricula. Final Report.
ERIC Educational Resources Information Center
Watson, Roy C.; Scobie, Walter R.
Since microcomputers are being used more and more frequently in the forest products industry in the Pacific Northwest, Green River Community College conducted a project to search for BASIC language computer programs pertaining to forestry, and when possible, to adapt such software for use in teaching forestry technology. The search for applicable…
Using Storytelling to Hone Language Skills
ERIC Educational Resources Information Center
Snider, Michelle
2008-01-01
A first glance into the classroom where Phillip Tillery teaches may leave visitors overwhelmed due by the array of high-tech equipment wired and ready for access by his students. Some students are working independently at computers while others are immersed in teams at a green screen and motion-capture setup. Various computer programs with myriad…
NASA Technical Reports Server (NTRS)
DeBonis, James R.
2013-01-01
A computational fluid dynamics code that solves the compressible Navier-Stokes equations was applied to the Taylor-Green vortex problem to examine the code s ability to accurately simulate the vortex decay and subsequent turbulence. The code, WRLES (Wave Resolving Large-Eddy Simulation), uses explicit central-differencing to compute the spatial derivatives and explicit Low Dispersion Runge-Kutta methods for the temporal discretization. The flow was first studied and characterized using Bogey & Bailley s 13-point dispersion relation preserving (DRP) scheme. The kinetic energy dissipation rate, computed both directly and from the enstrophy field, vorticity contours, and the energy spectra are examined. Results are in excellent agreement with a reference solution obtained using a spectral method and provide insight into computations of turbulent flows. In addition the following studies were performed: a comparison of 4th-, 8th-, 12th- and DRP spatial differencing schemes, the effect of the solution filtering on the results, the effect of large-eddy simulation sub-grid scale models, and the effect of high-order discretization of the viscous terms.
Irreducible Green's functions method for a quantum dot coupled to metallic and superconducting leads
NASA Astrophysics Data System (ADS)
Górski, Grzegorz; Kucab, Krzysztof
2017-05-01
Using irreducible Green's functions (IGF) method we analyse the Coulomb interaction dependence of the spectral functions and the transport properties of a quantum dot coupled to isotropic superconductor and metallic leads (SC-QD-N). The irreducible Green's functions method is the modification of classical equation of motion technique. The IGF scheme is based on differentiation of double-time Green's functions, both over the primary and secondary times. The IGF method allows to obtain the spectral functions for equilibrium and non-equilibrium impurity Anderson model used for SC-QD-N system. By the numerical computations, we show the change of spectral and the anomalous densities under the influence of the Coulomb interactions. The observed sign change of the anomalous spectral density can be used as the criterion of the SC singlet-Kondo singlet transition.
A multi-product green supply chain under government supervision with price and demand uncertainty
NASA Astrophysics Data System (ADS)
Hafezalkotob, Ashkan; Zamani, Soma
2018-05-01
In this paper, a bi-level game-theoretic model is proposed to investigate the effects of governmental financial intervention on green supply chain. This problem is formulated as a bi-level program for a green supply chain that produces various products with different environmental pollution levels. The problem is also regard uncertainties in market demand and sale price of raw materials and products. The model is further transformed into a single-level nonlinear programming problem by replacing the lower-level optimization problem with its Karush-Kuhn-Tucker optimality conditions. Genetic algorithm is applied as a solution methodology to solve nonlinear programming model. Finally, to investigate the validity of the proposed method, the computational results obtained through genetic algorithm are compared with global optimal solution attained by enumerative method. Analytical results indicate that the proposed GA offers better solutions in large size problems. Also, we conclude that financial intervention by government consists of green taxation and subsidization is an effective method to stabilize green supply chain members' performance.
Maximum entropy formalism for the analytic continuation of matrix-valued Green's functions
NASA Astrophysics Data System (ADS)
Kraberger, Gernot J.; Triebl, Robert; Zingl, Manuel; Aichhorn, Markus
2017-10-01
We present a generalization of the maximum entropy method to the analytic continuation of matrix-valued Green's functions. To treat off-diagonal elements correctly based on Bayesian probability theory, the entropy term has to be extended for spectral functions that are possibly negative in some frequency ranges. In that way, all matrix elements of the Green's function matrix can be analytically continued; we introduce a computationally cheap element-wise method for this purpose. However, this method cannot ensure important constraints on the mathematical properties of the resulting spectral functions, namely positive semidefiniteness and Hermiticity. To improve on this, we present a full matrix formalism, where all matrix elements are treated simultaneously. We show the capabilities of these methods using insulating and metallic dynamical mean-field theory (DMFT) Green's functions as test cases. Finally, we apply the methods to realistic material calculations for LaTiO3, where off-diagonal matrix elements in the Green's function appear due to the distorted crystal structure.
NASA Marshall Space Flight Center Solar Observatory report, January - June 1990
NASA Technical Reports Server (NTRS)
Smith, James E.
1990-01-01
A description of the NASA Marshall Space Flight Center's Solar Vector Magnetograph Facility is presented and a summary of its observations and data reduction is given. The systems that make up the facility are a magnetograph telescope, an H alpha telescope, a Questar telescope, and a computer code. The data are represented by longitudinal contours with azimuth plots.
NASA Marshall Space Flight Center solar observatory
NASA Technical Reports Server (NTRS)
Smith, James E.
1988-01-01
A description is provided of the NASA Marshall Space Flight Center's Solar Vector Magnetograph Facility and a summary is given of its observations and data reduction during Jan. to Mar. 1988. The systems that make up the facility are a magnetograph telescope, an H-alpha telescope, a Questar telescope, and a computer center. The data are represented by longitudinal contours with azimuth plots.
Tagliaferri, Roberto; Longo, Giuseppe; Milano, Leopoldo; Acernese, Fausto; Barone, Fabrizio; Ciaramella, Angelo; De Rosa, Rosario; Donalek, Ciro; Eleuteri, Antonio; Raiconi, Giancarlo; Sessa, Salvatore; Staiano, Antonino; Volpicelli, Alfredo
2003-01-01
In the last decade, the use of neural networks (NN) and of other soft computing methods has begun to spread also in the astronomical community which, due to the required accuracy of the measurements, is usually reluctant to use automatic tools to perform even the most common tasks of data reduction and data mining. The federation of heterogeneous large astronomical databases which is foreseen in the framework of the astrophysical virtual observatory and national virtual observatory projects, is, however, posing unprecedented data mining and visualization problems which will find a rather natural and user friendly answer in artificial intelligence tools based on NNs, fuzzy sets or genetic algorithms. This review is aimed to both astronomers (who often have little knowledge of the methodological background) and computer scientists (who often know little about potentially interesting applications), and therefore will be structured as follows: after giving a short introduction to the subject, we shall summarize the methodological background and focus our attention on some of the most interesting fields of application, namely: object extraction and classification, time series analysis, noise identification, and data mining. Most of the original work described in the paper has been performed in the framework of the AstroNeural collaboration (Napoli-Salerno).
NASA Astrophysics Data System (ADS)
Córsico, A. H.; Benvenuto, O. G.
Recently in our Observatory we have developed a new Stellar Pulsation Code, independently of other workers. Such program computes eigenvalues (eigenfrequencies) and eigenfunctions of non-radial modes in spherical non-perturbated stellar models. To accomplish this calculations, the four order eigenvalue problem (in the linear adiabatic approach) is solved by means of the well-know technique of Henyey on the finite differences scheme wich replace to the differential equations of the problem. In order to test the Code, we have computed numerous eigenmodes in polytropic configurations for several values of index n. In this comunication we show the excelent agreement of our results and that best available in the literature. Also, we present results of oscillations in models of white dwarf stars with homogeneus chemical composition (pure Helium). This models have been obtained with the Evolution Stellar Code of our Observatory. The calculations outlined above conform a first preliminary step in a major proyect whose main purpose is the study of pulsational properties of DA, DB and DO white dwarfs stars. Detailed investigations have demonstrated that such objets pulsates in non-radial g-modes with eigenperiods in the range 100-2000 sec.
Observatories and Telescopes of Modern Times
NASA Astrophysics Data System (ADS)
Leverington, David
2016-11-01
Preface; Part I. Optical Observatories: 1. Palomar Mountain Observatory; 2. The United States Optical Observatory; 3. From the Next Generation Telescope to Gemini and SOAR; 4. Competing primary mirror designs; 5. Active optics, adaptive optics and other technical innovations; 6. European Northern Observatory and Calar Alto; 7. European Southern Observatory; 8. Mauna Kea Observatory; 9. Australian optical observatories; 10. Mount Hopkins' Whipple Observatory and the MMT; 11. Apache Point Observatory; 12. Carnegie Southern Observatory (Las Campanas); 13. Mount Graham International Optical Observatory; 14. Modern optical interferometers; 15. Solar observatories; Part II. Radio Observatories: 16. Australian radio observatories; 17. Cambridge Mullard Radio Observatory; 18. Jodrell Bank; 19. Early radio observatories away from the Australian-British axis; 20. The American National Radio Astronomy Observatory; 21. Owens Valley and Mauna Kea; 22. Further North and Central American observatories; 23. Further European and Asian radio observatories; 24. ALMA and the South Pole; Name index; Optical observatory and telescope index; Radio observatory and telescope index; General index.
Operating a wide-area remote observing system for the W. M. Keck Observatory
NASA Astrophysics Data System (ADS)
Wirth, Gregory D.; Kibrick, Robert I.; Goodrich, Robert W.; Lyke, James E.
2008-07-01
For over a decade, the W. M. Keck Observatory's two 10-meter telescopes have been operated remotely from its Waimea headquarters. Over the last 6 years, WMKO remote observing has expanded to allow teams at dedicated sites in California to observe either in collaboration with colleagues in Waimea or entirely from the U.S. mainland. Once an experimental effort, the Observatory's mainland observing capability is now fully operational, supported on all science instruments (except the interferometer) and regularly used by astronomers at eight mainland sites. Establishing a convenient and secure observing capability from those sites required careful planning to ensure that they are properly equipped and configured. It also entailed a significant investment in hardware and software, including both custom scripts to simplify launching the instrument interface at remote sites and automated routers employing ISDN backup lines to ensure continuation of observing during Internet outages. Observers often wait until shortly before their runs to request use of the mainland facilities. Scheduling these requests and ensuring proper system operation prior to observing requires close coordination between personnel at WMKO and the mainland sites. An established protocol for approving requests and carrying out pre-run checkout has proven useful in ensuring success. The Observatory anticipates enhancing and expanding its remote observing system. Future plans include deploying dedicated summit computers for running VNC server software, implementing a web-based tracking system for mainland-based observing requests, expanding the system to additional mainland sites, and converting to full-time VNC operation for all instruments.
The characteristics of seismological data from offshore observatory in the northeastern South Korea
NASA Astrophysics Data System (ADS)
Cho, H. M.; Kim, G.; Che, I. Y.; Lim, I. S.; Kim, Y.; Shin, I. C.
2017-12-01
The real-time seismic observation in the ocean is challenging but provides unprecedented data appropriate for seismological research in the ocean from local to global scale. The offshore seismic observatory in the northeastern South Korea operated by Korea Institute of Geoscience and Mineral Resources (KIGAM) integrates the seismic, hydro-acoustic, and infrasound data and transmits the integrated data with oceanographic sensing and SOH (State of Health) to KIGAM in real-time. The observatory is equipped with ocean bottom broadband seismometer (120 s - 50 Hz) laid on the sea-floor approximately 80 meters below sea level. This study focuses on the properties of the data from the sea-floor, noise level evaluation of the observatory in the shallow water, and assessing event detection threshold of the offshore site. We computes the power spectral density (PSD) to describe the background seismic noise and its variations with seasonal change and meteorological condition. The seismic noise probability density functions from the PSDs shows that broadband seismic noise is generally high compared with the Peterson's NLNM and NHNM model. The statistical analysis of the seismic noise is given. We compares the noise level with that of the nearby onshore broadband seismometer. The quality of waveform data from the local, regional, and teleseismic earthquake are evaluated and compared with corresponding onshore data. The S-wave amplification is prominent on the sea-floor observations from local earthquake. The detection threshold on the local earthquake is estimated.
1991-04-01
This photograph shows the Compton Gamma-Ray Observatory (GRO) being deployed by the Remote Manipulator System (RMS) arm aboard the Space Shuttle Atlantis during the STS-37 mission in April 1991. The GRO reentered Earth atmosphere and ended its successful mission in June 2000. For nearly 9 years, the GRO Burst and Transient Source Experiment (BATSE), designed and built by the Marshall Space Flight Center (MSFC), kept an unblinking watch on the universe to alert scientists to the invisible, mysterious gamma-ray bursts that had puzzled them for decades. By studying gamma-rays from objects like black holes, pulsars, quasars, neutron stars, and other exotic objects, scientists could discover clues to the birth, evolution, and death of stars, galaxies, and the universe. The gamma-ray instrument was one of four major science instruments aboard the Compton. It consisted of eight detectors, or modules, located at each corner of the rectangular satellite to simultaneously scan the entire universe for bursts of gamma-rays ranging in duration from fractions of a second to minutes. In January 1999, the instrument, via the Internet, cued a computer-controlled telescope at Las Alamos National Laboratory in Los Alamos, New Mexico, within 20 seconds of registering a burst. With this capability, the gamma-ray experiment came to serve as a gamma-ray burst alert for the Hubble Space Telescope, the Chandra X-Ray Observatory, and major gound-based observatories around the world. Thirty-seven universities, observatories, and NASA centers in 19 states, and 11 more institutions in Europe and Russia, participated in the BATSE science program.
1991-04-01
This photograph shows the Compton Gamma-Ray Observatory being released from the Remote Manipulator System (RMS) arm aboard the Space Shuttle Atlantis during the STS-35 mission in April 1991. The GRO reentered the Earth's atmosphere and ended its successful mission in June 2000. For nearly 9 years, GRO's Burst and Transient Source Experiment (BATSE), designed and built by the Marshall Space Flight Center, kept an unblinking watch on the universe to alert scientist to the invisible, mysterious gamma-ray bursts that had puzzled them for decades. By studying gamma-rays from objects like black holes, pulsars, quasars, neutron stars, and other exotic objects, scientists could discover clues to the birth, evolution, and death of star, galaxies, and the universe. The gamma-ray instrument was one of four major science instruments aboard the Compton. It consisted of eight detectors, or modules, located at each corner of the rectangular satellite to simultaneously scan the entire universe for bursts of gamma-rays ranging in duration from fractions of a second to minutes. In January 1999, the instrument, via the Internet, cued a computer-controlled telescope at Las Alamos National Laboratory in Los Alamos, New Mexico, within 20 seconds of registering a burst. With this capability, the gamma-ray experiment came to serve as a gamma-ray burst alert for the Hubble Space Telescope, the Chandra X-Ray Observatory, and major gound-based observatories around the world. Thirty-seven universities, observatories, and NASA centers in 19 states, and 11 more institutions in Europe and Russia, participated in BATSE's science program.
NASA Astrophysics Data System (ADS)
Saha, Ratan K.; Fadhel, Muhannad N.; Lawrence, Aamna; Karmakar, Subhajit; Adhikari, Arunabha; Kolios, Michael C.
2017-03-01
Photoacoustic (PA) field calculations using a Green's function approach is presented. The method has been applied to predict PA spectra generated by normal (discocyte) and pathological (stomatocyte) red blood cells (RBCs). The contours of normal and pathological RBCs were generated by employing a popular parametric model and accordingly, fitted with the Legendre polynomial expansions for surface parametrization. The first frequency minimum of theoretical PA spectrum approximately appears at 607 MHz for a discocyte and 410 MHz for a stomatocyte when computed from the direction of symmetry axis. The same feature occurs nearly at 247 and 331 MHz, respectively, for those particles when measured along the perpendicular direction. The average experimental spectrum for normal RBCs is found to be flat over a bandwidth of 150-500 MHz when measured along the direction of symmetry axis. For spherical RBCs, both the theoretical and experimental spectra demonstrate negative slope over a bandwidth of 250-500 MHz. Using the Green's function method discussed, it may be possible to rapidly characterize cellular morphology from single-particle PA spectra.
Shear viscosity of the quark-gluon plasma in a kinetic theory approach
DOE Office of Scientific and Technical Information (OSTI.GOV)
Puglisi, A.; Plumari, S.; Scardina, F.
2014-05-09
One of the main results of heavy ions collision (HIC) at relativistic energy experiments is the very small shear viscosity to entropy density ratio of the Quark-Gluon Plasma, close to the conjectured lower bound η/s=1/4π for systems in the infinite coupling limit. Transport coefficients like shear viscosity are responsible of non-equilibrium properties of a system: Green-Kubo relations give us an exact expression to compute these coefficients. We compute shear viscosity numerically using Green-Kubo relation in the framework of Kinetic Theory solving the relativistic transport Boltzmann equation in a finite box with periodic boundary conditions. We investigate a system of particlesmore » interacting via anisotropic and energy dependent cross-section in the range of temperature of interest for HIC. Green-Kubo results are in agreement with Chapman-Enskog approximation while Relaxation Time approximation can underestimates the viscosity of a factor 2. The correct analytic formula for shear viscosity can be used to develop a transport theory with a fixed η/s and have a comparison with physical observables like elliptic flow.« less
NASA Astrophysics Data System (ADS)
Lovell, Amy J.; Amason, Charlee; Howell, Ellen S.; Presler-Marshall, Brynn A.; Reid, Sarah E.; Cunningham, Nichol; Frayer, David T.; Lockman, Felix J.; Church, Sarah E.
2017-10-01
We obtained 18cm OH spectra of comets 41P/Tuttle-Giacobini-Kresák (TGK) in early 2017 and 45P/Honda-Mrkos-Pajdušáková (HMP) in late 2016 and early 2017, using the Green Bank Observatory 100m R. W. Byrd Green Bank Telescope (GBT). Spectra of both comets were obtained at 1667 and 1665 MHz (18cm wavelength) with a beam resolution of 7.4 arcminutes. In spite of their close approaches to Earth, we only detected OH spectral lines with the telescope beam centered on the nucleus of the comets, so we are unable to make a direct constraint on collisional quenching, but using estimated quenching, we can obtain estimates for gas production rates. Spectral line widths and derived gas outflow velocities are low compared to other comets at these heliocentric distances, particularly for HMP, with best-fit water outflow velocities of 0.7-0.8 km/s at production rates around 2 x 1028 molecules per second. Best-fit velocities for TGK in mid-March, 2017 averaged 0.84 ± 0.04 km/s with gas production rates 1-2 x 1027 molecules per second. In addition, we obtained Director's Discretionary Time to employ the ARGUS mapping spectrometer at 90 GHz (3mm) to constrain emissions from HCN and HCO+. We will present gas outflow velocities for each detection and gas production rates or upper limits, as derived from best fits of Monte Carlo simulations.
NASA Astrophysics Data System (ADS)
Urban, S. E.; Corbin, T. E.; Wycoff, G. L.; Makarov, V. V.; Høg, E.; Fabricius, C.
2001-12-01
For over 100 years, the international project known as the Astrographic Catalogue -- which involved 20 observatories tasked to photograph the sky -- has held an unfulfilled promised of yielding a wealth of astrometric information. This promise was not realized due to the inadequate reductions of the project's plates. However, in 1997 the U.S. Naval Observatory (USNO) completed the reductions of the 22,660 plates. That catalogue, named the AC 2000, contained positions and magnitudes for 4.6 million stars down to about v magnitude 12.5. Due to the early epochs of the data -- averaging 1907 -- and the positional accuracies -- between 150 and 400 milliarcseconds -- the data are extremely valuable in computing proper motions. In 1997, these positions were used to form the proper motions of the ACT Reference Catalogue. In 1999, USNO and Copenhagen University Observatory (CUO) partnered to create the Tycho-2 Catalogue. The CUO group re-analyzed the data from the Tycho experiment on the Hipparcos satellite. The USNO group re-analyzed over 140 positional catalogs which were combined with the expanded Tycho positions from the CUO group to compute the Tycho-2 proper motions. The largest contributor to these proper motions was the re-analyzed Astrographic Catalogue; the latest version being known as the AC 2000.2 Catalogue. There are two major differences between the AC 2000 and the AC 2000.2. First, the reference catalog used in AC 2000.2 was an expanded version of the Astrographic Catalogue Reference Stars that was rigorously derived on the Hipparcos Celestial Reference Frame. The second is that AC 2000.2 contains photometry from Tycho-2, where available. A description of the AC 2000.2 Catalogue, the reduction techniques used, how it compares with the 1997 version, and information on obtaining the data will be presented.
Software development for a gamma-ray burst rapid-response observatory in the US Virgin Islands.
NASA Astrophysics Data System (ADS)
Davis, K. A.; Giblin, T. W.; Neff, J. E.; Hakkila, J.; Hartmann, D.
2004-12-01
The site is situated near the crest of Crown Mountain on the island of St. Thomas in the US Virgin Islands. The observing site is strategically located 65 W longitude, placing it as the most eastern GRB-dedicated observing site in the western hemisphere. The observatory has a 0.5 m robotic telescope and a Marconi 4240 2048 by 2048 CCD with BVRI filters. The field of view is identical to that of the XRT onboard Swift, 19 by 19 arc minutes. The telescope is operated through the Talon telescope control software. The observatory is notified of a burst trigger through the GRB Coordinates Network (GCN). This GCN notification is received through a socket connection to the control computer on site. A Perl script passes this information to the Talon software, which automatically interrupts concurrent observations and inserts a new GRB observing schedule. Once the observations are made the resulting images are then analyzed in IRAF. A source extraction is necessary to identify known sources and the optical transient. The system is being calibrated for automatic GRB response and is expected to be ready to follow up Swift observations. This work has been supported by NSF and NASA-EPSCoR.
A preliminary design study for a cosmic X-ray spectrometer
NASA Technical Reports Server (NTRS)
1972-01-01
The results are described of theoretical and experimental investigations aimed at the development of a curved crystal cosmic X-ray spectrometer to be used at the focal plane of the large orbiting X-ray telescope on the third High Energy Astronomical Observatory. The effort was concentrated on the development of spectrometer concepts and their evaluation by theoretical analysis, computer simulation, and laboratory testing with breadboard arrangements of crystals and detectors. In addition, a computer-controlled facility for precision testing and evaluation of crystals in air and vacuum was constructed. A summary of research objectives and results is included.
Energy star. (Latest citations from the Computer database). Published Search
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
The bibliography contains citations concerning a collaborative effort between the Environmental Protection Agency (EPA) and private industry to reduce electrical power consumed by personal computers and related peripherals. Manufacturers complying with EPA guidelines are officially recognized by award of a special Energy Star logo, and are referred to in official documents as a vendor of green computers. (Contains a minimum of 81 citations and includes a subject term index and title list.)
Energy star. (Latest citations from the Computer database). Published Search
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
The bibliography contains citations concerning a collaborative effort between the Environmental Protection Agency (EPA) and private industry to reduce electrical power consumed by personal computers and related peripherals. Manufacturers complying with EPA guidelines are officially recognized by award of a special Energy Star logo, and are referred to in official documents as a vendor of green computers. (Contains a minimum of 234 citations and includes a subject term index and title list.)
Private Observatories in South Africa
NASA Astrophysics Data System (ADS)
Rijsdijk, C.
2016-12-01
Descriptions of private observatories in South Africa, written by their owners. Positions, equipment descriptions and observing programmes are given. Included are: Klein Karoo Observatory (B. Monard), Cederberg Observatory (various), Centurion Planetary and Lunar Observatory (C. Foster), Le Marischel Observatory (L. Ferreira), Sterkastaaing Observatory (M. Streicher), Henley on Klip (B. Fraser), Archer Observatory (B. Dumas), Overbeek Observatory (A. Overbeek), Overberg Observatory (A. van Staden), St Cyprian's School Observatory, Fisherhaven Small Telescope Observatory (J. Retief), COSPAR 0433 (G. Roberts), COSPAR 0434 (I. Roberts), Weltevreden Karoo Observatory (D. Bullis), Winobs (M. Shafer)
Image analysis and green tea color change kinetics during thin-layer drying.
Shahabi, Mohammad; Rafiee, Shahin; Mohtasebi, Seyed Saeid; Hosseinpour, Soleiman
2014-09-01
This study was conducted to investigate the effect of air temperature and air flow velocity on kinetics of color parameter changes during hot-air drying of green tea, to obtain the best model for hot-air drying of green tea, to apply a computer vision system and to study the color changes during drying. In the proposed computer vision system system, at first RGB values of the images were converted into XYZ values and then to Commission International d'Eclairage L*a*b* color coordinates. The obtained color parameters of L*, a* and b* were calibrated with Hunter-Lab colorimeter. These values were also used for calculation of the color difference, chroma, hue angle and browning index. The values of L* and b* decreased, while the values of a* and color difference (ΔE*ab ) increased during hot-air drying. Drying data were fitted to three kinetic models. Zero, first-order and fractional conversion models were utilized to describe the color changes of green tea. The suitability of fitness was determined using the coefficient of determination (R (2)) and root-mean-square error. Results showed that the fraction conversion model had more acceptable fitness than the other two models in most of color parameters. © The Author(s) 2013 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.
NASA Technical Reports Server (NTRS)
Rouse, J. W., Jr. (Principal Investigator); Haas, R. H.; Deering, D. W.; Schell, J. A.; Harlan, J. C.
1974-01-01
The author has identified the following significant results. The Great Plains Corridor rangeland project successfully utilized natural vegetation systems as phenological indicators of seasonal development and climatic effects upon regional growth conditions. An effective method was developed for quantitative measurement of vegetation conditions, including green biomass estimates, recorded in bands 5 and 6, corrected for sun angle, were used to compute a ratio parameter (TV16) which is shown to be highly correlated with green biomass and vegatation moisture content. Analyses results of ERTS-1 digital data and correlated ground data are summarized. Attention was given to analyzing weather influences and test site variables on vegetation condition measurements with ERTS-1 data.
Improved upper winds models for several astronomical observatories.
Roberts, Lewis C; Bradford, L William
2011-01-17
An understanding of wind speed and direction as a function of height are critical to the proper modeling of atmospheric turbulence. We have used radiosonde data from launch sites near significant astronomical observatories and created averaged profiles of wind speed and direction and have also computed Richardson number profiles. Using data from the last 30 years, we confirm a 1977 Greenwood wind profile, and extend it to include parameters that show seasonal variations and differences in location. The added information from our models is useful for the design of adaptive optics systems and other imaging systems. Our analysis of the Richardson number suggests that persistent turbulent layers may be inferred when low values are present in our long term averaged data. Knowledge of the presence of these layers may help with planning for adaptive optics and laser communications.
Applying Squeaky-Wheel Optimization Schedule Airborne Astronomy Observations
NASA Technical Reports Server (NTRS)
Frank, Jeremy; Kuerklue, Elif
2004-01-01
We apply the Squeaky Wheel Optimization (SWO) algorithm to the problem of scheduling astronomy observations for the Stratospheric Observatory for Infrared Astronomy, an airborne observatory. The problem contains complex constraints relating the feasibility of an astronomical observation to the position and time at which the observation begins, telescope elevation limits, special use airspace, and available fuel. Solving the problem requires making discrete choices (e.g. selection and sequencing of observations) and continuous ones (e.g. takeoff time and setting up observations by repositioning the aircraft). The problem also includes optimization criteria such as maximizing observing time while simultaneously minimizing total flight time. Previous approaches to the problem fail to scale when accounting for all constraints. We describe how to customize SWO to solve this problem, and show that it finds better flight plans, often with less computation time, than previous approaches.
NASA Technical Reports Server (NTRS)
1974-01-01
The work breakdown structure (WBS) dictionary for the Earth Observatory Satellite (EOS) is defined. The various elements of the EOS program are examined to include the aggregate of hardware, computer software, services, and data required to develop, produce, test, support, and operate the space vehicle and the companion ground data management system. A functional analysis of the EOS mission is developed. The operations for three typical EOS missions, Delta, Titan, and Shuttle launched are considered. The functions were determined for the top program elements, and the mission operations, function 2.0, was expanded to level one functions. Selection of ten level one functions for further analysis to level two and three functions were based on concern for the EOS operations and associated interfaces.
Grote Reber, Radio Astronomy Pioneer, Dies
NASA Astrophysics Data System (ADS)
2002-12-01
Grote Reber, one of the earliest pioneers of radio astronomy, died in Tasmania on December 20, just two days shy of his 91st birthday. Reber was the first person to build a radio telescope dedicated to astronomy, opening up a whole new "window" on the Universe that eventually produced such landmark discoveries as quasars, pulsars and the remnant "afterglow" of the Big Bang. His self- financed experiments laid the foundation for today's advanced radio-astronomy facilities. Grote Reber Grote Reber NRAO/AUI photo "Radio astronomy has changed profoundly our understanding of the Universe and has earned the Nobel Prize for several major contributions. All radio astronomers who have followed him owe Grote Reber a deep debt for his pioneering work," said Dr. Fred Lo, director of the National Radio Astronomy Observatory (NRAO). "Reber was the first to systematically study the sky by observing something other than visible light. This gave astronomy a whole new view of the Universe. The continuing importance of new ways of looking at the Universe is emphasized by this year's Nobel Prizes in physics, which recognized scientists who pioneered X-ray and neutrino observations," Lo added. Reber was a radio engineer and avid amateur "ham" radio operator in Wheaton, Illinois, in the 1930s when he read about Karl Jansky's 1932 discovery of natural radio emissions coming from outer space. As an amateur operator, Reber had won awards and communicated with other amateurs around the world, and later wrote that he had concluded "there were no more worlds to conquer" in radio. Learning of Jansky's discovery gave Reber a whole new challenge that he attacked with vigor. Analyzing the problem as an engineer, Reber concluded that what he needed was a parabolic-dish antenna, something quite uncommon in the 1930s. In 1937, using his own funds, he constructed a 31.4-foot-diameter dish antenna in his back yard. The strange contraption attracted curious attention from his neighbors and became something of a minor tourist attraction, he later recalled. Using electronics he designed and built that pushed the technical capabilities of the era, Reber succeeded in detecting "cosmic static" in 1939. In 1941, Reber produced the first radio map of the sky, based on a series of systematic observations. His radio-astronomy work continued over the next several years. Though not a professional scientist, his research results were published in a number of prestigious technical journals, including Nature, the Astrophysical Journal, the Proceedings of the Institute of Radio Engineers and the Journal of Geophysical Research. Reber also received a number of honors normally reserved for scientists professionally trained in astronomy, including the American Astronomical Society's Henry Norris Russell Lectureship and the Astronomical Society of the Pacific's Bruce Medal in 1962, the National Radio Astronomy Observatory's Jansky Lectureship in 1975, and the Royal Astronomical Society's Jackson-Gwilt Medal in 1983. Reber's original dish antenna now is on display at the National Radio Astronomy Observatory's site in Green Bank, West Virginia, where Reber worked in the late 1950s. All of his scientific papers and records as well as his personal and scientific correspondence are held by the NRAO, and will be exhibited in the observatory's planned new library in Charlottesville, Virginia. Reber's amateur-radio callsign, W9GFZ, is held by the NRAO Amateur Radio Club. This callsign was used on the air for the first time since the 1930s on August 25, 2000, to mark the dedication of the Robert C. Byrd Green Bank Telescope. The National Radio Astronomy Observatory is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc.
Service-Oriented Architecture for NVO and TeraGrid Computing
NASA Technical Reports Server (NTRS)
Jacob, Joseph; Miller, Craig; Williams, Roy; Steenberg, Conrad; Graham, Matthew
2008-01-01
The National Virtual Observatory (NVO) Extensible Secure Scalable Service Infrastructure (NESSSI) is a Web service architecture and software framework that enables Web-based astronomical data publishing and processing on grid computers such as the National Science Foundation's TeraGrid. Characteristics of this architecture include the following: (1) Services are created, managed, and upgraded by their developers, who are trusted users of computing platforms on which the services are deployed. (2) Service jobs can be initiated by means of Java or Python client programs run on a command line or with Web portals. (3) Access is granted within a graduated security scheme in which the size of a job that can be initiated depends on the level of authentication of the user.
Coupled RANS/LES for SOFIA Cavity Acoustic Prediction
NASA Technical Reports Server (NTRS)
Woodruff, Stephen L.
2010-01-01
A fast but accurate approach is described for the determination of the aero-acoustic properties of a large cavity at subsonic flight speeds. This approach employs a detachededdy simulation model in the free-shear layer at the cavity opening and the surrounding boundary layer, but assumes inviscid flow in the cavity and in the far field. The reduced gridding requirements in the cavity, in particular, lead to dramatic improvements in the time required for the computation. Results of these computations are validated against wind-tunnel data. This approach will permit significantly more flight test points to be evaluated computationally in support of the Stratospheric Observatory For Infrared Astronomy flight-test program being carried out at NASA s Dryden Flight Research Center.
Effects of building roof greening on air quality in street canyons
NASA Astrophysics Data System (ADS)
Baik, Jong-Jin; Kwak, Kyung-Hwan; Park, Seung-Bu; Ryu, Young-Hee
2012-12-01
Building roof greening is a successful strategy for improving urban thermal environment. It is of theoretical interest and practical importance to study the effects of building roof greening on urban air quality in a systematic and quantitative way. In this study, we examine the effects of building roof greening on air quality in street canyons using a computational fluid dynamics (CFD) model that includes the thermodynamic energy equation and the transport equation of passive, non-reactive pollutants. For simplicity, building roof greening is represented by specified cooling. Results for a simple building configuration with a street canyon aspect ratio of one show that the cool air produced due to building roof greening flows into the street canyon, giving rise to strengthened street canyon flow. The strengthened street canyon flow enhances pollutant dispersion near the road, which decreases pollutant concentration there. Thus, building roof greening improves air quality near the road. The degree of air quality improvement near the road increases as the cooling intensity increases. In the middle region of the street canyon, the air quality can worsen when the cooling intensity is not too strong. Results for a real urban morphology also show that building roof greening improves air quality near roads. The degree of air quality improvement near roads due to building roof greening depends on the ambient wind direction. These findings provide a theoretical foundation for constructing green roofs for the purpose of improving air quality near roads or at a pedestrian level as well as urban thermal environment. Further studies using a CFD model coupled with a photochemistry model and a surface energy balance model are required to evaluate the effects of building roof greening on air quality in street canyons in a more realistic framework.
KITAGAWA, HIROYUKI; NAMIKAWA, TSUTOMU; IWABU, JUN; HANAZAKI, KAZUHIRO
2017-01-01
We report a case of gastric tube reconstruction with superdrainage using indocyanine green fluorescence during esophagectomy for esophageal cancer. A 53-year-old man with a history of early esophageal cancer treated with endoscopic mucosal dissection experienced esophageal cancer recurrence. There was no evidence of lymph node involvement or distant metastasis on computed tomography; therefore, we performed thoracoscopic esophagectomy. After thoracoscopic esophagectomy, we created a gastric tube. When pulling up the gastric tube through the post-mediastinum route, a root of the right gastroepiploic vein was injured. We subsequently performed superdrainage to avoid congestion of the gastric tube with omental vein and pre-tracheal vein anastomosis at the neck, and confirmed venous flow using the indocyanine green fluorescence method. No postoperative anastomotic leakage was observed, and the patient was discharged 22 days after surgery. Thus, we recommend the indocyanine green fluorescence method in cases involving superdrainage during esophagectomy. PMID:28882975
The NANOGrav 11-year Data Set: High-precision Timing of 45 Millisecond Pulsars
NASA Astrophysics Data System (ADS)
Arzoumanian, Zaven; Brazier, Adam; Burke-Spolaor, Sarah; Chamberlin, Sydney; Chatterjee, Shami; Christy, Brian; Cordes, James M.; Cornish, Neil J.; Crawford, Fronefield; Thankful Cromartie, H.; Crowter, Kathryn; DeCesar, Megan E.; Demorest, Paul B.; Dolch, Timothy; Ellis, Justin A.; Ferdman, Robert D.; Ferrara, Elizabeth C.; Fonseca, Emmanuel; Garver-Daniels, Nathan; Gentile, Peter A.; Halmrast, Daniel; Huerta, E. A.; Jenet, Fredrick A.; Jessup, Cody; Jones, Glenn; Jones, Megan L.; Kaplan, David L.; Lam, Michael T.; Lazio, T. Joseph W.; Levin, Lina; Lommen, Andrea; Lorimer, Duncan R.; Luo, Jing; Lynch, Ryan S.; Madison, Dustin; Matthews, Allison M.; McLaughlin, Maura A.; McWilliams, Sean T.; Mingarelli, Chiara; Ng, Cherry; Nice, David J.; Pennucci, Timothy T.; Ransom, Scott M.; Ray, Paul S.; Siemens, Xavier; Simon, Joseph; Spiewak, Renée; Stairs, Ingrid H.; Stinebring, Daniel R.; Stovall, Kevin; Swiggum, Joseph K.; Taylor, Stephen R.; Vallisneri, Michele; van Haasteren, Rutger; Vigeland, Sarah J.; Zhu, Weiwei; The NANOGrav Collaboration
2018-04-01
We present high-precision timing data over time spans of up to 11 years for 45 millisecond pulsars observed as part of the North American Nanohertz Observatory for Gravitational Waves (NANOGrav) project, aimed at detecting and characterizing low-frequency gravitational waves. The pulsars were observed with the Arecibo Observatory and/or the Green Bank Telescope at frequencies ranging from 327 MHz to 2.3 GHz. Most pulsars were observed with approximately monthly cadence, and six high-timing-precision pulsars were observed weekly. All were observed at widely separated frequencies at each observing epoch in order to fit for time-variable dispersion delays. We describe our methods for data processing, time-of-arrival (TOA) calculation, and the implementation of a new, automated method for removing outlier TOAs. We fit a timing model for each pulsar that includes spin, astrometric, and (for binary pulsars) orbital parameters; time-variable dispersion delays; and parameters that quantify pulse-profile evolution with frequency. The timing solutions provide three new parallax measurements, two new Shapiro delay measurements, and two new measurements of significant orbital-period variations. We fit models that characterize sources of noise for each pulsar. We find that 11 pulsars show significant red noise, with generally smaller spectral indices than typically measured for non-recycled pulsars, possibly suggesting a different origin. A companion paper uses these data to constrain the strength of the gravitational-wave background.
Crab Nebula from Five Observatories
2017-05-10
In the summer of the year 1054 AD, Chinese astronomers saw a new "guest star," that appeared six times brighter than Venus. So bright in fact, it could be seen during the daytime for several months. This "guest star" was forgotten about until 700 years later with the advent of telescopes. Astronomers saw a tentacle-like nebula in the place of the vanished star and called it the Crab Nebula. Today we know it as the expanding gaseous remnant from a star that self-detonated as a supernova, briefly shining as brightly as 400 million suns. The explosion took place 6,500 light-years away. If the blast had instead happened 50 light-years away it would have irradiated Earth, wiping out most life forms. In the late 1960s astronomers discovered the crushed heart of the doomed star, an ultra-dense neutron star that is a dynamo of intense magnetic field and radiation energizing the nebula. Astronomers therefore need to study the Crab Nebula across a broad range of electromagnetic radiation, from X-rays to radio waves. This image combines data from five different telescopes: the VLA (radio) in red; Spitzer Space Telescope (infrared) in yellow; Hubble Space Telescope (visible) in green; XMM-Newton (ultraviolet) in blue; and Chandra X-ray Observatory (X-ray) in purple. More images and an animation are available at https://photojournal.jpl.nasa.gov/catalog/PIA21474
Range indices of geomagnetic activity
Stuart, W.F.; Green, A.W.
1988-01-01
The simplest index of geomagnetic activity is the range in nT from maximum to minimum value of the field in a given time interval. The hourly range R was recommended by IAGA for use at observatories at latitudes greater than 65??, but was superceded by AE. The most used geomagnetic index K is based on the range of activity in a 3 h interval corrected for the regular daily variation. In order to take advantage of real time data processing, now available at many observatories, it is proposed to introduce a 1 h range index and also a 3 h range index. Both will be computed hourly, i.e. each will have a series of 24 per day, the 3 h values overlapping. The new data will be available as the range (R) of activity in nT and also as a logarithmic index (I) of the range. The exponent relating index to range in nT is based closely on the scale used for computing K values. The new ranges and range indices are available, from June 1987, to users in real time and can be accessed by telephone connection or computer network. Their first year of production is regarded as a trial period during which their value to the scientific and commercial communities will be assessed, together with their potential as indicators of regional and global disturbances' and in which trials will be conducted into ways of eliminating excessive bias at quiet times due to the rate of change of the daily variation field. ?? 1988.
NASA Marshall Space Flight Center Solar Observatory report, October - December 1990
NASA Technical Reports Server (NTRS)
Smith, James E.
1991-01-01
A description of the NASA Marshall Space Flight Center's Solar Vector Magnetograph Facility is provided, and a summary of its observations and data reduction during Oct. - Dec. 1990 is presented. The systems that make up the facility are a magnetograph telescope, and H-alpha telescope, a Questar telescope, and a computer code. The data are represented by longitudinal contours with azimuth plots.
NASA Marshall Space Flight Center solar observatory report, January - December 1987
NASA Technical Reports Server (NTRS)
Smith, James E.
1989-01-01
This report provides a description of the NASA Marshall Space Flight Center's Solar Vector Magnetograph Facility and gives a summary of its observations and data reduction during January to December 1987. The systems that make up the facility are a magnetograph telescope, an H-alpha telescope, a Questar telescope, and a computer code. The data are represented by longitudinal contours with azimuth plots.
NASA Marshall Space Flight Center Solar Observatory report, July - September 1990
NASA Technical Reports Server (NTRS)
Smith, James E.
1991-01-01
A description of the NASA Marshall Space Flight C nter's Solar Vector Magnetograph Facility is provided and gives a summary of its observations and data reduction during Jul. - Sep. 1990. The systems that make up the facility are a magnetograph telescope, an H-alpha telescope, a Questar telescope, and a computer code. The data are represented by longitudinal contours with azimuth plots.
NASA Marshall Space Flight Center solar observatory report, January to December 1989
NASA Technical Reports Server (NTRS)
Smith, James E.
1990-01-01
A description is provided of the NASA-Marshall's Solar Vector Magnetograph Facility and a summary of its observations and data reduction during January to December 1989 is given. The systems that make up the facility are a magnetograph telescope, and H-alpha telescope, a Questar telescope, and a computer code. The data are represented by longitudinal contours with azimuth plots.
Astronomy in Inca Empire: a Ceque Based Calendar
NASA Astrophysics Data System (ADS)
Correa, Nathalia Silva Gomes; de Nader, R. V.
2007-08-01
This work is a brief report about different kinds of arrangements and organization of the Inca astronomical calendar, approaching archaeological vestiges in Cuzco, such as observatories aligned to celestial objects which were observed for the computation of the time. We also analyze the ceques lines that can be associated to these techniques of Inca astronomical observation, according to the chroniclers and the researches in archaeoastronomy.
NASA Astrophysics Data System (ADS)
Nghiem, A.; Thurnhoffer, B. M.; Bishop, J. K. B.; Kim, H.
2014-12-01
Particles constitute a significant portion of the flux weathered material from continents to ocean basins but little is understood about their seasonal dynamics particularly in subsurface and headwater stream environments. At the Eel River Critical Zone Observatory, located near the headwaters of the South Fork Eel River in the Angelo Coast Range Reserve (Northern California), groundwater from weathered bedrock and stream waters are sampled at a frequency of one to three days from three wells (Well 1 down-slope, Well 3 mid-slope, Well 10 upper-slope) and Elder Creek. Approximately one thousand samples collected by automated ISCO Gravity Filtration System (GFS; Kim et al. 2012, EST) since 2011 have been filtered through 0.45 μm 25 mm diameter Supor filters. Filters imaged under controlled lighting are analyzed for red, green, and blue optical density (OD) to enable rapid assessment of sample loading and color as a prelude to and selection aid for more labor-intensive ICP-MS and Scanning Electron Microscopic analysis. For example, samples with lower red OD relative to green and blue may correspond to samples high in Mn/Fe oxides. Optical imaging of the loaded filters provides a time-series over three years and color anomalies in these filters along with chemical analysis of dissolved and particulate filtrate is used to establish a method for calibrating optical data to interpret chemical composition of water and particles. Results are interpreted within a framework of environmental data such as rainfall, stream discharge and turbidity, and water table depth measured at the heavily monitored forested hillslope. Data from the four locations range up to 0.6 OD units with a typical detection limit of better than 0.01 OD units. At Well 10, wet season filter samples exhibit highest particle loading (OD ~ 0.3) with values rapidly decreasing during the dry season (OD < D.L.) water table recession. At Well 1, particle loads instantaneously reflect intense rain events. Applied at a larger scale, this method - if proven - may be used to estimate basin level particulate flux with an estimation of chemical composition in a highly efficient manner.
Color Composite Image of the Supernova Remnant
NASA Technical Reports Server (NTRS)
2000-01-01
This image is a color composite of the supernova remnant E0102-72: x-ray (blue), optical (green), and radio (red). E0102-72 is the remnant of a star that exploded in a nearby galaxy known as the Small Magellanic Cloud. The star exploded outward at speeds in excess of 20 million kilometers per hour (12 million mph) and collided with surrounding gas. This collision produced two shock waves, or cosmic sonic booms, one traveling outward, and the other rebounding back into the material ejected by the explosion. The radio image, shown in red, was made using the Australia Telescope Compact Array. The radio waves are due to extremely high-energy electrons spiraling around magnetic field lines in the gas and trace the outward moving shock wave. The Chandra X-ray Observatory image, shown in blue, shows gas that has been heated to millions of degrees by the rebounding, or reverse shock wave. The x-ray data show that this gas is rich in oxygen and neon. These elements were created by nuclear reactions inside the star and hurled into space by the supernova. The Hubble Space Telescope optical image, shown in green, shows dense clumps of oxygen gas that have 'cooled' to about 30,000 degrees. Photo Credit: X-ray (NASA/CXC/SAO); optical (NASA/HST): radio: (ACTA)
NASA Astrophysics Data System (ADS)
Jelinkova, Vladmira; Dohnal, Michal; Picek, Tomas; Sacha, Jan
2015-04-01
Understanding the performance of technogenic substrates for green roofs is a significant task in the framework of sustainable urban planning and water/energy management. The potential retention and detention of the anthropogenic, light weight soil systems and their temporal soil structure changes are of major importance. A green roof test segment was built to investigate the benefits of such anthropogenic systems. Adaptable low-cost system allows long-term monitoring of preferred characteristics. Temperature and water balance measurements complemented with meteorological observations and knowledge of physical properties of the substrates provide basis for detailed analysis of thermal and hydrological regime in green roof systems. The first results confirmed the benefits of green roof systems. The reduction of temperature fluctuations as well as rainfall runoff was significant. Depending on numerous factors such substrate material or vegetation cover the test green roof suppressed the roof temperature amplitude for the period analyzed. The ability to completely prevent (light rainfall events) or reduce and delay (medium and heavy rainfall events) the peak runoff was also analyzed. Special attention is being paid to the assessment of soil structural properties related to possible aggregation/disaggregation, root growth, weather conditions and associated structural changes using non-invasive imaging method. X-ray computed microtomography of undisturbed soil samples (taken from experimental segments) is used for description of pore space geometry, evaluation of surface to volume ratio, additionally for description of cracks and macropores as a product of soil flora and fauna activity. The information from computed tomography imaging will be used for numerical modeling of water flow in variable saturated porous media. The research was realized as a part of the University Centre for Energy Efficient Buildings supported by the EU and with financial support from the Czech Science Foundation under project number 14-10455P.
Removing the Impact of Baluns from Measurements of a Novel Antenna for Cosmological HI Measurements
NASA Astrophysics Data System (ADS)
Trung, Vincent; Ewall-Wice, Aaron Michael; Li, Jianshu; Hewitt, Jacqueline; Riley, Daniel; Bradley, Richard F.; Makhija, Krishna; Garza, Sierra; HERA Collaboration
2018-01-01
The Hydrogen Epoch of Reionization Array (HERA) is a low-frequency radio interferometer aiming to detect redshifted 21 cm emission from neutral hydrogen during the Epoch of Reionization at frequencies between 100 and 200 MHz. Extending HERA’s performance to lower frequencies will enable detection of radio waves at higher redshifts, when models predict that gas between galaxies was heated by X-rays from the first stellar-mass black holes. The isolation of foregrounds that are four orders of magnitude brighter than the faint cosmological signal presents and unprecedented set of design specifications for our antennas, including sensitivity and spectral smoothness over a large bandwidth. We are developing a broadband sinuous antenna feed for HERA, extending the bandwidth from 50 to 220 MHz, and we are verifying antenna performance with field measurements and simulations. Electromagnetic simulations compute the differential S-parameters of the antenna. We measure these S-parameters through a lossy balun attached to an unbalanced vector network analyzer. Removing the impact of this balun is critical in obtaining an accurate comparison between our simulations and measurements. I describe measurements to characterize the baluns and how they are used to remove the balun’s impact on the antenna S-parameter measurements. Field measurements of the broadband sinuous antenna dish at MIT and Green Bank Observatory are used to verify our electromagnetic simulations of the broadband sinuous antenna design. After applying our balun corrections, we find that our field measurements are in good agreement with the simulation, giving us confidence that our feeds will perform as designed.
Energy star. (Latest citations from the Computer database). Published Search
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
The bibliography contains citations concerning a collaborative effort between the Environmental Protection Agency (EPA) and private industry to reduce electrical power consumed by personal computers and related peripherals. Manufacturers complying with EPA guidelines are officially recognized by award of a special Energy Star logo, and are referred to in official documents as a vendor of green computers. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)
NASA Technical Reports Server (NTRS)
Chiu, Y. T.; Hilton, H. H.
1977-01-01
Exact closed-form solutions to the solar force-free magnetic-field boundary-value problem are obtained for constant alpha in Cartesian geometry by a Green's function approach. The uniqueness of the physical problem is discussed. Application of the exact results to practical solar magnetic-field calculations is free of series truncation errors and is at least as economical as the approximate methods currently in use. Results of some test cases are presented.
Laplace transforms of the Hulthén Green's function and their application to potential scattering
NASA Astrophysics Data System (ADS)
Laha, U.; Ray, S.; Panda, S.; Bhoi, J.
2017-10-01
We derive closed-form representations for the single and double Laplace transforms of the Hulthén Green's function of the outgoing wave multiplied by the Yamaguchi potential and write them in the maximally reduced form. We use the expression for the double transform to compute the low-energy phase shifts for the elastic scattering in the systems α-nucleon, α-He3, and α-H3. The calculation results agree well with the experimental data.
Design of a sampling plan to detect ochratoxin A in green coffee.
Vargas, E A; Whitaker, T B; Dos Santos, E A; Slate, A B; Lima, F B; Franca, R C A
2006-01-01
The establishment of maximum limits for ochratoxin A (OTA) in coffee by importing countries requires that coffee-producing countries develop scientifically based sampling plans to assess OTA contents in lots of green coffee before coffee enters the market thus reducing consumer exposure to OTA, minimizing the number of lots rejected, and reducing financial loss for producing countries. A study was carried out to design an official sampling plan to determine OTA in green coffee produced in Brazil. Twenty-five lots of green coffee (type 7 - approximately 160 defects) were sampled according to an experimental protocol where 16 test samples were taken from each lot (total of 16 kg) resulting in a total of 800 OTA analyses. The total, sampling, sample preparation, and analytical variances were 10.75 (CV = 65.6%), 7.80 (CV = 55.8%), 2.84 (CV = 33.7%), and 0.11 (CV = 6.6%), respectively, assuming a regulatory limit of 5 microg kg(-1) OTA and using a 1 kg sample, Romer RAS mill, 25 g sub-samples, and high performance liquid chromatography. The observed OTA distribution among the 16 OTA sample results was compared to several theoretical distributions. The 2 parameter-log normal distribution was selected to model OTA test results for green coffee as it gave the best fit across all 25 lot distributions. Specific computer software was developed using the variance and distribution information to predict the probability of accepting or rejecting coffee lots at specific OTA concentrations. The acceptation probability was used to compute an operating characteristic (OC) curve specific to a sampling plan design. The OC curve was used to predict the rejection of good lots (sellers' or exporters' risk) and the acceptance of bad lots (buyers' or importers' risk).
Integrated Multiscale Modeling of Molecular Computing Devices
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gregory Beylkin
2012-03-23
Significant advances were made on all objectives of the research program. We have developed fast multiresolution methods for performing electronic structure calculations with emphasis on constructing efficient representations of functions and operators. We extended our approach to problems of scattering in solids, i.e. constructing fast algorithms for computing above the Fermi energy level. Part of the work was done in collaboration with Robert Harrison and George Fann at ORNL. Specific results (in part supported by this grant) are listed here and are described in greater detail. (1) We have implemented a fast algorithm to apply the Green's function for themore » free space (oscillatory) Helmholtz kernel. The algorithm maintains its speed and accuracy when the kernel is applied to functions with singularities. (2) We have developed a fast algorithm for applying periodic and quasi-periodic, oscillatory Green's functions and those with boundary conditions on simple domains. Importantly, the algorithm maintains its speed and accuracy when applied to functions with singularities. (3) We have developed a fast algorithm for obtaining and applying multiresolution representations of periodic and quasi-periodic Green's functions and Green's functions with boundary conditions on simple domains. (4) We have implemented modifications to improve the speed of adaptive multiresolution algorithms for applying operators which are represented via a Gaussian expansion. (5) We have constructed new nearly optimal quadratures for the sphere that are invariant under the icosahedral rotation group. (6) We obtained new results on approximation of functions by exponential sums and/or rational functions, one of the key methods that allows us to construct separated representations for Green's functions. (7) We developed a new fast and accurate reduction algorithm for obtaining optimal approximation of functions by exponential sums and/or their rational representations.« less
NASA Astrophysics Data System (ADS)
2010-01-01
ESO has just released a stunning new image of the vast cloud known as the Cat's Paw Nebula or NGC 6334. This complex region of gas and dust, where numerous massive stars are born, lies near the heart of the Milky Way galaxy, and is heavily obscured by intervening dust clouds. Few objects in the sky have been as well named as the Cat's Paw Nebula, a glowing gas cloud resembling the gigantic pawprint of a celestial cat out on an errand across the Universe. British astronomer John Herschel first recorded NGC 6334 in 1837 during his stay in South Africa. Despite using one of the largest telescopes in the world at the time, Herschel seems to have only noted the brightest part of the cloud, seen here towards the lower left. NGC 6334 lies about 5500 light-years away in the direction of the constellation Scorpius (the Scorpion) and covers an area on the sky slightly larger than the full Moon. The whole gas cloud is about 50 light-years across. The nebula appears red because its blue and green light are scattered and absorbed more efficiently by material between the nebula and Earth. The red light comes predominantly from hydrogen gas glowing under the intense glare of hot young stars. NGC 6334 is one of the most active nurseries of massive stars in our galaxy and has been extensively studied by astronomers. The nebula conceals freshly minted brilliant blue stars - each nearly ten times the mass of our Sun and born in the last few million years. The region is also home to many baby stars that are buried deep in the dust, making them difficult to study. In total, the Cat's Paw Nebula could contain several tens of thousands of stars. Particularly striking is the red, intricate bubble in the lower right part of the image. This is most likely either a star expelling large amount of matter at high speed as it nears the end of its life or the remnant of a star that already has exploded. This new portrait of the Cat's Paw Nebula was created from images taken with the Wide Field Imager (WFI) instrument at the 2.2-metre MPG/ESO telescope at the La Silla Observatory in Chile, combining images taken through blue, green and red filters, as well as a special filter designed to let through the light of glowing hydrogen. More information ESO, the European Southern Observatory, is the foremost intergovernmental astronomy organisation in Europe and the world's most productive astronomical observatory. It is supported by 14 countries: Austria, Belgium, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Portugal, Spain, Sweden, Switzerland and the United Kingdom. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope, the world's most advanced visible-light astronomical observatory and VISTA, the world's largest survey telescope. ESO is the European partner of a revolutionary astronomical telescope ALMA, the largest astronomical project in existence. ESO is currently planning a 42-metre European Extremely Large optical/near-infrared Telescope, the E-ELT, which will become "the world's biggest eye on the sky".
Powering Down from the Bottom up: Greener Client Computing
ERIC Educational Resources Information Center
O'Donnell, Tom
2009-01-01
A decade ago, people wanting to practice "green computing" recycled their printer paper, turned their personal desktop systems off from time to time, and tried their best to donate old equipment to a nonprofit instead of throwing it away. A campus IT department can shave a few watts off just about any IT process--the real trick is planning and…
Computing Areas Using Green's Theorem and a Software Planimeter
ERIC Educational Resources Information Center
Davis, Paul; Raianu, Serban
2007-01-01
According to the Merriam-Webster dictionary, a planimeter is "an instrument for measuring the area of a plane figure by tracing its boundary line". Even without knowing how a planimeter works, it is clear from the definition that the idea behind it is that one can compute the area of a figure just by "walking" on the boundary. For someone who has…
Side-branch resonators modelling with Green's function methods
NASA Astrophysics Data System (ADS)
Perrey-Debain, E.; Maréchal, R.; Ville, J. M.
2014-09-01
This paper deals with strategies for computing efficiently the propagation of sound waves in ducts containing passive components. In many cases of practical interest, these components are acoustic cavities which are connected to the duct. Though standard Finite Element software could be used for the numerical prediction of sound transmission through such a system, the method is known to be extremely demanding, both in terms of data preparation and computation, especially in the mid-frequency range. To alleviate this, a numerical technique that exploits the benefit of the FEM and the BEM approach has been devised. First, a set of eigenmodes is computed in the cavity to produce a numerical impedance matrix connecting the pressure and the acoustic velocity on the duct wall interface. Then an integral representation for the acoustic pressure in the main duct is used. By choosing an appropriate Green's function for the duct, the integration procedure is limited to the duct-cavity interface only. This allows an accurate computation of the scattering matrix of such an acoustic system with a numerical complexity that grows very mildly with the frequency. Typical applications involving Helmholtz and Herschel-Quincke resonators are presented.
A coarse-grid projection method for accelerating incompressible flow computations
NASA Astrophysics Data System (ADS)
San, Omer; Staples, Anne
2011-11-01
We present a coarse-grid projection (CGP) algorithm for accelerating incompressible flow computations, which is applicable to methods involving Poisson equations as incompressibility constraints. CGP methodology is a modular approach that facilitates data transfer with simple interpolations and uses black-box solvers for the Poisson and advection-diffusion equations in the flow solver. Here, we investigate a particular CGP method for the vorticity-stream function formulation that uses the full weighting operation for mapping from fine to coarse grids, the third-order Runge-Kutta method for time stepping, and finite differences for the spatial discretization. After solving the Poisson equation on a coarsened grid, bilinear interpolation is used to obtain the fine data for consequent time stepping on the full grid. We compute several benchmark flows: the Taylor-Green vortex, a vortex pair merging, a double shear layer, decaying turbulence and the Taylor-Green vortex on a distorted grid. In all cases we use either FFT-based or V-cycle multigrid linear-cost Poisson solvers. Reducing the number of degrees of freedom of the Poisson solver by powers of two accelerates these computations while, for the first level of coarsening, retaining the same level of accuracy in the fine resolution vorticity field.
Calculating the carbon emissions associated with San Jose's Green Vision goals
NASA Astrophysics Data System (ADS)
Cordero, E. C.; Prada, L.
2010-12-01
In 2007, the City of San Jose adopted a Green Vision that includes 10 measurable goals, which aim to promote job growth in clean tech and preserve the environment. The goals include a 50% reduction of per capita energy use, a 100% diversion of waste from landfill, a 100% recycling or reuse of wastewater, and the building or retro fitting of 50 million square feet of green buildings. While there are clear benefits from these initiatives, it is unclear how these changes will affect emissions of greenhouse gases and what contribution the Green Vision will have on the total carbon emissions of the city. Using San Jose as a case study this work will first estimate citywide baseline carbon emissions using data from the last decade. We then will describe efforts to compute the change in carbon emissions associated with each of the city’s green vision goals. The intention of this work is to develop a set of metrics that other cities and institutions can use to better quantify the carbon emissions associated with their current and future ‘green’ initiatives.
Education and Public Outreach Programs at Columbus State University's Mead Observatory
NASA Astrophysics Data System (ADS)
Cruzen, S.; Rutland, C.; Carr, D.; Seckinger, M.
2003-12-01
Columbus State University (CSU) has made a substantial commitment to community education in astronomy and space science. Through the programs of the Mead Observatory at CSU's Coca-Cola Space Science Center, students, staff and faculty have been providing public outreach programs in astronomy for more than seven years. Recently, a generous grant from a private foundation has facilitated an astounding growth in the observatory's astronomy outreach activities. The grant made possible the purchase of a van, a portable planetarium, and additional telescope and computer equipment. It also funded a two-year scholarship that has supported a pair of CSU's science education majors who have staffed the program and made it a success. NASA, through the Georgia Space Grant Consortium, has provided additional funding for scholarships for 2003-2004. Prior to receiving these funds, the observatory program consisted of monthly open houses, occasional public observing nights at remote locations and approximately 6 to 8 school visits per year. Annually, these programs served approximately 3500 people. Since beginning the new phase of this program in October of 2001, the number of people served has soared to more than 23,000 in only 24 months. Over 60 schools have been visited, increasing our previous annual rate by nearly five times. Additional groups served include boys and girls scouting groups, state parks and other community organizations. School presentations have been designed to assist K-12 teachers in meeting science education standards. More than 200 teachers were asked to assess the program, and their responses were quite positive. More information about the program is available at our website (http://www.ccssc.org).
2006-06-05
Space shuttle STS-121 FIT (Fly Immunity and Tumors) payload. Using Drosophila (fruit fly) to complete the experiments. Computer screen showing green fluorescent protein used to visualize blood cells in Drosophila (fruit fly).
A global analysis of the 1991 geomagnetic jerk
NASA Astrophysics Data System (ADS)
De Michelis, Paola; Cafarella, Lili; Meloni, Antonio
2000-12-01
A recent examination of the geomagnetic annual mean values for the European magnetic observatories has shown the existence of a sudden change in the secular acceleration in about 1991 (Cafarella & Meloni 1995; Macmillan 1996). Using first differences of the Y (east geomagnetic field component) mean values from 74 observatories, the worldwide character of the 1991 impulse has been determined (De Michelis et al. 1998). Using data from 109 observatories widely distributed all over the world, the structure of the secular variation for the X (north) and Z (vertical) magnetic field intensities around 1990 was investigated, and evidence of this most recent jerk was found. External effects were removed from the annual mean data by comparing the long-term variations of the geomagnetic field components at individual observatories with the long-term variations of two geomagnetic indices, aa and Dst, and of a solar index, the Wolf number R. A careful analysis has been carried out on the amplitude of the external disturbance, on its dependence on latitude, and on the weights of the geomagnetic indices in the evaluation of the resulting external field. The secular variation has been evaluated from the corrected annual means. Around 1990, the secular variation can be fitted at many observatories by two straight lines with a sudden and marked change in slope. In this manner the jerk occurrence time and the intensity of the step in the second time derivative (ΔX'', ΔY'' and ΔZ'') were computed. Maps of ΔX'', ΔY'' and ΔZ'' provide information on the worldwide intensity distribution of the examined event. Maps of the jerk occurrence-time distributions are also given. The mean jerk occurrence time is 1990.1+/-0.6. Finally, a spherical harmonic analysis was used to complete the quantitative description of this phenomenon in order to study the trend of the energy density spectrum as a function of the harmonic degree n.
Kinematics of AWM and MKW Poor Clusters
NASA Astrophysics Data System (ADS)
Koranyi, Daniel M.; Geller, Margaret J.
2002-01-01
We have measured 1365 redshifts to a limiting magnitude of R~15.5 in 15 AWM/MKW clusters and have collected another 203 from the literature in MKW 4s, MKW 2, and MKW 2s. In AWM 7 we have extended the redshift sample to R~18 in the cluster center. We have identified 704 cluster members in 17 clusters; 201 are newly identified. We summarize the kinematics and distributions of the cluster galaxies and provide an initial discussion of substructure, mass and luminosity segregation, spectral segregation, velocity-dispersion profiles, and the relation of the central galaxy to global cluster properties. We compute optical mass estimates, which we compare with X-ray mass determinations from the literature. The clusters are in a variety of dynamical states, reflected in the three classes of behavior of the velocity-dispersion profile in the core: rising, falling, or flat/ambiguous. The velocity dispersion of the emission-line galaxy population significantly exceeds that of the absorption-line galaxies in almost all of the clusters, and the presence of emission-line galaxies at small projected radii suggests continuing infall of galaxies onto the clusters. The presence of a cD galaxy does not constrain the global cluster properties; these clusters are similar to other poor clusters that contain no cD. We use the similarity of the velocity-dispersion profiles at small radii and the cD-like galaxies' internal velocity dispersions to argue that cD formation is a local phenomenon. Our sample establishes an empirical observational baseline of poor clusters for comparison with simulations of similar systems. Observations reported in this paper were obtained at the Multiple Mirror Telescope Observatory, a facility operated jointly by the University of Arizona and the Smithsonian Institution; at the Whipple Observatory, a facility operated jointly by the Smithsonian Astrophysical Observatory and Harvard University; and at the WIYN Observatory, a joint facility of the University of Wisconsin-Madison, Indiana University, Yale University, and the National Optical Astronomy Observatories.
NASA Astrophysics Data System (ADS)
Bashardanesh, Zahedeh; Lötstedt, Per
2018-03-01
In diffusion controlled reversible bimolecular reactions in three dimensions, a dissociation step is typically followed by multiple, rapid re-association steps slowing down the simulations of such systems. In order to improve the efficiency, we first derive an exact Green's function describing the rate at which an isolated pair of particles undergoing reversible bimolecular reactions and unimolecular decay separates beyond an arbitrarily chosen distance. Then the Green's function is used in an algorithm for particle-based stochastic reaction-diffusion simulations for prediction of the dynamics of biochemical networks. The accuracy and efficiency of the algorithm are evaluated using a reversible reaction and a push-pull chemical network. The computational work is independent of the rates of the re-associations.
NASA Astrophysics Data System (ADS)
Romanovsky, V. E.; Cable, W.; Walker, D. A.; Yoshikawa, K.; Marchenko, S. S.
2013-12-01
The impact of climate warming on permafrost and the potential of climate feedbacks resulting from permafrost thawing have recently received a great deal of attention. Most of the permafrost observatories in the Northern Hemisphere show substantial warming of permafrost since circa 1980-1990. The magnitude of warming has varied with location, but was typically from 0.5 to 2°C. Permafrost is already thawing within the southern part of the permafrost domain. However, recent observations documented propagation of this process northward into the continuous permafrost zone. The close proximity of the exceptionally icy soil horizons to the ground surface, which is typical for the arctic tundra biome, makes tundra surfaces extremely sensitive to the natural and human-made changes that may resulted in development of processes such as thermokarst, thermal erosion, and retrogressive thaw slumps that strongly affect the stability of ecosystems and infrastructure. In 2003-2005, three Ecological Permafrost Observatories where established in the High Canadian Arctic (Green Cabin on the Banks Island, Mould Bay on the Prince Patrick Island, and Isachsen on the Ellef Ringnes Island) as a part of the University of Alaska Fairbanks NSF funded Biocomplexity Project. These observatories represent the northern part of the North American Arctic Transect (NAAT) established as a result of this project. The climatic and ground temperature data collected at these observatories show a general warming trend similar to what has been observed at the other locations in the North American Arctic. An important result of this resent warming is a significant increase in the active layer thickness (ALT) during the last decade. For example, ALT at the Isachsen observatory increased from 0.4-0.42 m in 2005 to 0.54 m in 2012. The maximum ALT of 0.58 m was recorded in 2008. In a shallow excavation across an ice wedge at the Isachsen site, we estimated that the top of the ice wedge ice was located at 42-45 cm from the ground surface in 2005. Increase in the active layer beyond this depth triggered the melting of the upper part of the ice wedges and widespread ground settlement at this location. In our presentation we will report on the observed changes in local topography in relation to changes in ground temperature and ALT at all three mentioned sites. In 2001, a Permafrost Observatory was also established within the Barrow Environmental Observatory in Barrow, Alaska under the auspices of the International Arctic Research Center of the University of Alaska Fairbanks. Since 2001, permafrost temperature at this depth increased by 0.5°C. Most of this increase happened after 2005. A site-specific numerical model for the Barrow permafrost temperature regime was developed in the GI Permafrost Lab. The daily air temperatures and snow cover thickness during the entire period of measurements (1924-2013) at the Barrow meteorological station were used as input data. Analysis of the resulting time series will be used in this presentation to reveal the effect of changes in air temperature and in snow depth on permafrost temperature and on the active layer thickness. This will help to put our decade-long observations along NAAT into a longer time perspective.
First Results of the Near Real-Time Imaging Reconstruction System at Big Bear Solar Observatory
NASA Astrophysics Data System (ADS)
Yang, G.; Denker, C.; Wang, H.
2003-05-01
The Near Real-Time Imaging Reconstruction system (RTIR) at Big Bear Solar Observatory (BBSO) is designed to obtain high spatial resolution solar images at a cadence of 1 minute utilizing the power of parallel processing. With this system, we can compute near diffraction-limited images without saving huge amounts of data that are involved in the speckle masking reconstruction algorithm. It enables us to monitor active regions and give fast response to the solar activity. In this poster we present the first results of our new 32-CPU Beowulf cluster system. The images are 1024 x 1024 and the field of view (FOV) is 80'' x 80''. Our target is an active region with complex magnetic configuration. We focus on pores and small spots in the active region with the goal of better understanding the formation of penumbra structure. In addition we expect to study evolution of active regions during solar flares.
Infrared Astrophysics in the SOFIA Era - An Overview
NASA Astrophysics Data System (ADS)
Yorke, Harold W.
2018-06-01
The Stratospheric Observatory for Infrared Astronomy (SOFIA) provides the international astronomical community access to a broad range of instrumentation that covers wavelengths spanning the near to far infrared. The high spectral resolution of many of these instruments in several wavelength bands is unmatched by any existing or near future planned facility. The far infrared polarization capabilities of one of its instruments, HAWC+, is also unique. Moreover, SOFIA allows for additional instrument augmentations, as new state-of-the-art photometric, spectrometric, and polarimetric capabilities have been added and are being further improved. The fact that SOFIA provides ample mass, power, computing capabilities as well as 4K cooling eases the constraints on future instrument design, technical readiness, and the instrument build to an extent not possible for space-borne missions. We will review SOFIA's current and future planned capabilities and highlight specific science areas for which the stratospheric observatory will be able to significantly advance Origins science topics.
The TAROT Suspected Variable Star Catalog
NASA Astrophysics Data System (ADS)
Damerdji, Y.; Klotz, A.; Boër, M.
2007-04-01
TAROT (Télescope à Action Rapide pour les Objets Transitoires) is a robotic observatory designed to observe very early optical transients of gamma-ray bursts (GRBs). As GRBs do not often occur, we use TAROT for various other celestial targets spread over the sky. For every field observed by TAROT, we computed the magnitudes of every star. From this work, we found 1175 new variable stars brighter than 17 mag. We selected the best variable star candidates and compiled them in the TSVSC1 (TAROT Suspected Variable Star Catalog, ver. 1), which also contains Fourier-series coefficients that fit the light curves. Based on observations collected with the TAROT instrument at the Calern Observatory, France. Complementary observations were carried out with the T80 telescope at the Observatoire de Haute-Provence, France. Additional material described in § 5 is available in electronic format at the CDS at http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/AJ/.
NASA Astrophysics Data System (ADS)
Pierre Auger Collaboration; Abreu, P.; Aglietta, M.; Ahn, E. J.; Albuquerque, I. F. M.; Allard, D.; Allekotte, I.; Allen, J.; Allison, P.; Alvarez Castillo, J.; Alvarez-Muñiz, J.; Ambrosio, M.; Aminaei, A.; Anchordoqui, L.; Andringa, S.; Antičić, T.; Anzalone, A.; Aramo, C.; Arganda, E.; Arqueros, F.; Asorey, H.; Assis, P.; Aublin, J.; Ave, M.; Avenier, M.; Avila, G.; Bäcker, T.; Balzer, M.; Barber, K. B.; Barbosa, A. F.; Bardenet, R.; Barroso, S. L. C.; Baughman, B.; Bäuml, J.; Beatty, J. J.; Becker, B. R.; Becker, K. H.; Bellétoile, A.; Bellido, J. A.; Benzvi, S.; Berat, C.; Bertou, X.; Biermann, P. L.; Billoir, P.; Blanco, F.; Blanco, M.; Bleve, C.; Blümer, H.; Boháčová, M.; Boncioli, D.; Bonifazi, C.; Bonino, R.; Borodai, N.; Brack, J.; Brogueira, P.; Brown, W. C.; Bruijn, R.; Buchholz, P.; Bueno, A.; Burton, R. E.; Caballero-Mora, K. S.; Caramete, L.; Caruso, R.; Castellina, A.; Catalano, O.; Cataldi, G.; Cazon, L.; Cester, R.; Chauvin, J.; Cheng, S. H.; Chiavassa, A.; Chinellato, J. A.; Chou, A.; Chudoba, J.; Clay, R. W.; Coluccia, M. R.; Conceição, R.; Contreras, F.; Cook, H.; Cooper, M. J.; Coppens, J.; Cordier, A.; Coutu, S.; Covault, C. E.; Creusot, A.; Criss, A.; Cronin, J.; Curutiu, A.; Dagoret-Campagne, S.; Dallier, R.; Dasso, S.; Daumiller, K.; Dawson, B. R.; de Almeida, R. M.; de Domenico, M.; de Donato, C.; de Jong, S. J.; de La Vega, G.; de Mello Junior, W. J. M.; de Mello Neto, J. R. T.; de Mitri, I.; de Souza, V.; de Vries, K. D.; Decerprit, G.; Del Peral, L.; Del Río, M.; Deligny, O.; Dembinski, H.; Dhital, N.; di Giulio, C.; Diaz, J. C.; Díaz Castro, M. L.; Diep, P. N.; Dobrigkeit, C.; Docters, W.; D'Olivo, J. C.; Dong, P. N.; Dorofeev, A.; Dos Anjos, J. C.; Dova, M. T.; D'Urso, D.; Dutan, I.; Ebr, J.; Engel, R.; Erdmann, M.; Escobar, C. O.; Espadanal, J.; Etchegoyen, A.; Facal San Luis, P.; Fajardo Tapia, I.; Falcke, H.; Farrar, G.; Fauth, A. C.; Fazzini, N.; Ferguson, A. P.; Ferrero, A.; Fick, B.; Filevich, A.; Filipčič, A.; Fliescher, S.; Fracchiolla, C. E.; Fraenkel, E. D.; Fröhlich, U.; Fuchs, B.; Gaior, R.; Gamarra, R. F.; Gambetta, S.; García, B.; García Gámez, D.; Garcia-Pinto, D.; Gascon, A.; Gemmeke, H.; Gesterling, K.; Ghia, P. L.; Giaccari, U.; Giller, M.; Glass, H.; Gold, M. S.; Golup, G.; Gomez Albarracin, F.; Gómez Berisso, M.; Gonçalves, P.; Gonzalez, D.; Gonzalez, J. G.; Gookin, B.; Góra, D.; Gorgi, A.; Gouffon, P.; Gozzini, S. R.; Grashorn, E.; Grebe, S.; Griffith, N.; Grigat, M.; Grillo, A. F.; Guardincerri, Y.; Guarino, F.; Guedes, G. P.; Guzman, A.; Hague, J. D.; Hansen, P.; Harari, D.; Harmsma, S.; Harton, J. L.; Haungs, A.; Hebbeker, T.; Heck, D.; Herve, A. E.; Hojvat, C.; Hollon, N.; Holmes, V. C.; Homola, P.; Hörandel, J. R.; Horneffer, A.; Hrabovský, M.; Huege, T.; Insolia, A.; Ionita, F.; Italiano, A.; Jarne, C.; Jiraskova, S.; Josebachuili, M.; Kadija, K.; Kampert, K. H.; Karhan, P.; Kasper, P.; Kégl, B.; Keilhauer, B.; Keivani, A.; Kelley, J. L.; Kemp, E.; Kieckhafer, R. M.; Klages, H. O.; Kleifges, M.; Kleinfeller, J.; Knapp, J.; Koang, D.-H.; Kotera, K.; Krohm, N.; Krömer, O.; Kruppke-Hansen, D.; Kuehn, F.; Kuempel, D.; Kulbartz, J. K.; Kunka, N.; La Rosa, G.; Lachaud, C.; Lautridou, P.; Leão, M. S. A. B.; Lebrun, D.; Lebrun, P.; Leigui de Oliveira, M. A.; Lemiere, A.; Letessier-Selvon, A.; Lhenry-Yvon, I.; Link, K.; López, R.; Lopez Agüera, A.; Louedec, K.; Lozano Bahilo, J.; Lu, L.; Lucero, A.; Ludwig, M.; Lyberis, H.; Maccarone, M. C.; Macolino, C.; Maldera, S.; Mandat, D.; Mantsch, P.; Mariazzi, A. G.; Marin, J.; Marin, V.; Maris, I. C.; Marquez Falcon, H. R.; Marsella, G.; Martello, D.; Martin, L.; Martinez, H.; Martínez Bravo, O.; Mathes, H. J.; Matthews, J.; Matthews, J. A. J.; Matthiae, G.; Maurizio, D.; Mazur, P. O.; Medina-Tanco, G.; Melissas, M.; Melo, D.; Menichetti, E.; Menshikov, A.; Mertsch, P.; Meurer, C.; Mićanović, S.; Micheletti, M. I.; Miller, W.; Miramonti, L.; Molina-Bueno, L.; Mollerach, S.; Monasor, M.; Monnier Ragaigne, D.; Montanet, F.; Morales, B.; Morello, C.; Moreno, E.; Moreno, J. C.; Morris, C.; Mostafá, M.; Moura, C. A.; Mueller, S.; Muller, M. A.; Müller, G.; Münchmeyer, M.; Mussa, R.; Navarra, G.; Navarro, J. L.; Navas, S.; Necesal, P.; Nellen, L.; Nelles, A.; Neuser, J.; Nhung, P. T.; Niemietz, L.; Nierstenhoefer, N.; Nitz, D.; Nosek, D.; Nožka, L.; Nyklicek, M.; Oehlschläger, J.; Olinto, A.; Oliva, P.; Olmos-Gilbaja, V. M.; Ortiz, M.; Pacheco, N.; Pakk Selmi-Dei, D.; Palatka, M.; Pallotta, J.; Palmieri, N.; Parente, G.; Parizot, E.; Parra, A.; Parsons, R. D.; Pastor, S.; Paul, T.; Pech, M.; PeĶala, J.; Pelayo, R.; Pepe, I. M.; Perrone, L.; Pesce, R.; Petermann, E.; Petrera, S.; Petrinca, P.; Petrolini, A.; Petrov, Y.; Petrovic, J.; Pfendner, C.; Phan, N.; Piegaia, R.; Pierog, T.; Pieroni, P.; Pimenta, M.; Pirronello, V.; Platino, M.; Ponce, V. H.; Pontz, M.; Privitera, P.; Prouza, M.; Quel, E. J.; Querchfeld, S.; Rautenberg, J.; Ravel, O.; Ravignani, D.; Revenu, B.; Ridky, J.; Riggi, S.; Risse, M.; Ristori, P.; Rivera, H.; Rizi, V.; Roberts, J.; Robledo, C.; Rodrigues de Carvalho, W.; Rodriguez, G.; Rodriguez Martino, J.; Rodriguez Rojo, J.; Rodriguez-Cabo, I.; Rodríguez-Frías, M. D.; Ros, G.; Rosado, J.; Rossler, T.; Roth, M.; Rouillé-D'Orfeuil, B.; Roulet, E.; Rovero, A. C.; Rühle, C.; Salamida, F.; Salazar, H.; Salina, G.; Sánchez, F.; Santo, C. E.; Santos, E.; Santos, E. M.; Sarazin, F.; Sarkar, B.; Sarkar, S.; Sato, R.; Scharf, N.; Scherini, V.; Schieler, H.; Schiffer, P.; Schmidt, A.; Schmidt, F.; Scholten, O.; Schoorlemmer, H.; Schovancova, J.; Schovánek, P.; Schröder, F.; Schulte, S.; Schuster, D.; Sciutto, S. J.; Scuderi, M.; Segreto, A.; Settimo, M.; Shadkam, A.; Shellard, R. C.; Sidelnik, I.; Sigl, G.; Silva Lopez, H. H.; Śmiałkowski, A.; Šmída, R.; Snow, G. R.; Sommers, P.; Sorokin, J.; Spinka, H.; Squartini, R.; Stanic, S.; Stapleton, J.; Stasielak, J.; Stephan, M.; Strazzeri, E.; Stutz, A.; Suarez, F.; Suomijärvi, T.; Supanitsky, A. D.; Šuša, T.; Sutherland, M. S.; Swain, J.; Szadkowski, Z.; Szuba, M.; Tamashiro, A.; Tapia, A.; Tartare, M.; Taşcău, O.; Tavera Ruiz, C. G.; Tcaciuc, R.; Tegolo, D.; Thao, N. T.; Thomas, D.; Tiffenberg, J.; Timmermans, C.; Tiwari, D. K.; Tkaczyk, W.; Todero Peixoto, C. J.; Tomé, B.; Tonachini, A.; Travnicek, P.; Tridapalli, D. B.; Tristram, G.; Trovato, E.; Tueros, M.; Ulrich, R.; Unger, M.; Urban, M.; Valdés Galicia, J. F.; Valiño, I.; Valore, L.; van den Berg, A. M.; Varela, E.; Vargas Cárdenas, B.; Vázquez, J. R.; Vázquez, R. A.; Veberič, D.; Verzi, V.; Vicha, J.; Videla, M.; Villaseñor, L.; Wahlberg, H.; Wahrlich, P.; Wainberg, O.; Walz, D.; Warner, D.; Watson, A. A.; Weber, M.; Weidenhaupt, K.; Weindl, A.; Westerhoff, S.; Whelan, B. J.; Wieczorek, G.; Wiencke, L.; Wilczyńska, B.; Wilczyński, H.; Will, M.; Williams, C.; Winchen, T.; Winnick, M. G.; Wommer, M.; Wundheiler, B.; Yamamoto, T.; Yapici, T.; Younk, P.; Yuan, G.; Yushkov, A.; Zamorano, B.; Zas, E.; Zavrtanik, D.; Zavrtanik, M.; Zaw, I.; Zepeda, A.; Zimbres Silva, M.; Ziolkowski, M.
2012-01-01
We present the results of an analysis of data recorded at the Pierre Auger Observatory in which we search for groups of directionally-aligned events (or 'multiplets') which exhibit a correlation between arrival direction and the inverse of the energy. These signatures are expected from sets of events coming from the same source after having been deflected by intervening coherent magnetic fields. The observation of several events from the same source would open the possibility to accurately reconstruct the position of the source and also measure the integral of the component of the magnetic field orthogonal to the trajectory of the cosmic rays. We describe the largest multiplets found and compute the probability that they appeared by chance from an isotropic distribution. We find no statistically significant evidence for the presence of multiplets arising from magnetic deflections in the present data.
The IceCube Neutrino Observatory: instrumentation and online systems
NASA Astrophysics Data System (ADS)
Aartsen, M. G.; Ackermann, M.; Adams, J.; Aguilar, J. A.; Ahlers, M.; Ahrens, M.; Altmann, D.; Andeen, K.; Anderson, T.; Ansseau, I.; Anton, G.; Archinger, M.; Argüelles, C.; Auer, R.; Auffenberg, J.; Axani, S.; Baccus, J.; Bai, X.; Barnet, S.; Barwick, S. W.; Baum, V.; Bay, R.; Beattie, K.; Beatty, J. J.; Becker Tjus, J.; Becker, K.-H.; Bendfelt, T.; BenZvi, S.; Berley, D.; Bernardini, E.; Bernhard, A.; Besson, D. Z.; Binder, G.; Bindig, D.; Bissok, M.; Blaufuss, E.; Blot, S.; Boersma, D.; Bohm, C.; Börner, M.; Bos, F.; Bose, D.; Böser, S.; Botner, O.; Bouchta, A.; Braun, J.; Brayeur, L.; Bretz, H.-P.; Bron, S.; Burgman, A.; Burreson, C.; Carver, T.; Casier, M.; Cheung, E.; Chirkin, D.; Christov, A.; Clark, K.; Classen, L.; Coenders, S.; Collin, G. H.; Conrad, J. M.; Cowen, D. F.; Cross, R.; Day, C.; Day, M.; de André, J. P. A. M.; De Clercq, C.; del Pino Rosendo, E.; Dembinski, H.; De Ridder, S.; Descamps, F.; Desiati, P.; de Vries, K. D.; de Wasseige, G.; de With, M.; DeYoung, T.; Díaz-Vélez, J. C.; di Lorenzo, V.; Dujmovic, H.; Dumm, J. P.; Dunkman, M.; Eberhardt, B.; Edwards, W. R.; Ehrhardt, T.; Eichmann, B.; Eller, P.; Euler, S.; Evenson, P. A.; Fahey, S.; Fazely, A. R.; Feintzeig, J.; Felde, J.; Filimonov, K.; Finley, C.; Flis, S.; Fösig, C.-C.; Franckowiak, A.; Frère, M.; Friedman, E.; Fuchs, T.; Gaisser, T. K.; Gallagher, J.; Gerhardt, L.; Ghorbani, K.; Giang, W.; Gladstone, L.; Glauch, T.; Glowacki, D.; Glüsenkamp, T.; Goldschmidt, A.; Gonzalez, J. G.; Grant, D.; Griffith, Z.; Gustafsson, L.; Haack, C.; Hallgren, A.; Halzen, F.; Hansen, E.; Hansmann, T.; Hanson, K.; Haugen, J.; Hebecker, D.; Heereman, D.; Helbing, K.; Hellauer, R.; Heller, R.; Hickford, S.; Hignight, J.; Hill, G. C.; Hoffman, K. D.; Hoffmann, R.; Hoshina, K.; Huang, F.; Huber, M.; Hulth, P. O.; Hultqvist, K.; In, S.; Inaba, M.; Ishihara, A.; Jacobi, E.; Jacobsen, J.; Japaridze, G. S.; Jeong, M.; Jero, K.; Jones, A.; Jones, B. J. P.; Joseph, J.; Kang, W.; Kappes, A.; Karg, T.; Karle, A.; Katz, U.; Kauer, M.; Keivani, A.; Kelley, J. L.; Kemp, J.; Kheirandish, A.; Kim, J.; Kim, M.; Kintscher, T.; Kiryluk, J.; Kitamura, N.; Kittler, T.; Klein, S. R.; Kleinfelder, S.; Kleist, M.; Kohnen, G.; Koirala, R.; Kolanoski, H.; Konietz, R.; Köpke, L.; Kopper, C.; Kopper, S.; Koskinen, D. J.; Kowalski, M.; Krasberg, M.; Krings, K.; Kroll, M.; Krückl, G.; Krüger, C.; Kunnen, J.; Kunwar, S.; Kurahashi, N.; Kuwabara, T.; Labare, M.; Laihem, K.; Landsman, H.; Lanfranchi, J. L.; Larson, M. J.; Lauber, F.; Laundrie, A.; Lennarz, D.; Leich, H.; Lesiak-Bzdak, M.; Leuermann, M.; Lu, L.; Ludwig, J.; Lünemann, J.; Mackenzie, C.; Madsen, J.; Maggi, G.; Mahn, K. B. M.; Mancina, S.; Mandelartz, M.; Maruyama, R.; Mase, K.; Matis, H.; Maunu, R.; McNally, F.; McParland, C. P.; Meade, P.; Meagher, K.; Medici, M.; Meier, M.; Meli, A.; Menne, T.; Merino, G.; Meures, T.; Miarecki, S.; Minor, R. H.; Montaruli, T.; Moulai, M.; Murray, T.; Nahnhauer, R.; Naumann, U.; Neer, G.; Newcomb, M.; Niederhausen, H.; Nowicki, S. C.; Nygren, D. R.; Obertacke Pollmann, A.; Olivas, A.; O'Murchadha, A.; Palczewski, T.; Pandya, H.; Pankova, D. V.; Patton, S.; Peiffer, P.; Penek, Ö.; Pepper, J. A.; Pérez de los Heros, C.; Pettersen, C.; Pieloth, D.; Pinat, E.; Price, P. B.; Przybylski, G. T.; Quinnan, M.; Raab, C.; Rädel, L.; Rameez, M.; Rawlins, K.; Reimann, R.; Relethford, B.; Relich, M.; Resconi, E.; Rhode, W.; Richman, M.; Riedel, B.; Robertson, S.; Rongen, M.; Roucelle, C.; Rott, C.; Ruhe, T.; Ryckbosch, D.; Rysewyk, D.; Sabbatini, L.; Sanchez Herrera, S. E.; Sandrock, A.; Sandroos, J.; Sandstrom, P.; Sarkar, S.; Satalecka, K.; Schlunder, P.; Schmidt, T.; Schoenen, S.; Schöneberg, S.; Schukraft, A.; Schumacher, L.; Seckel, D.; Seunarine, S.; Solarz, M.; Soldin, D.; Song, M.; Spiczak, G. M.; Spiering, C.; Stanev, T.; Stasik, A.; Stettner, J.; Steuer, A.; Stezelberger, T.; Stokstad, R. G.; Stößl, A.; Ström, R.; Strotjohann, N. L.; Sulanke, K.-H.; Sullivan, G. W.; Sutherland, M.; Taavola, H.; Taboada, I.; Tatar, J.; Tenholt, F.; Ter-Antonyan, S.; Terliuk, A.; Tešić, G.; Thollander, L.; Tilav, S.; Toale, P. A.; Tobin, M. N.; Toscano, S.; Tosi, D.; Tselengidou, M.; Turcati, A.; Unger, E.; Usner, M.; Vandenbroucke, J.; van Eijndhoven, N.; Vanheule, S.; van Rossem, M.; van Santen, J.; Vehring, M.; Voge, M.; Vogel, E.; Vraeghe, M.; Wahl, D.; Walck, C.; Wallace, A.; Wallraff, M.; Wandkowsky, N.; Weaver, Ch.; Weiss, M. J.; Wendt, C.; Westerhoff, S.; Wharton, D.; Whelan, B. J.; Wickmann, S.; Wiebe, K.; Wiebusch, C. H.; Wille, L.; Williams, D. R.; Wills, L.; Wisniewski, P.; Wolf, M.; Wood, T. R.; Woolsey, E.; Woschnagg, K.; Xu, D. L.; Xu, X. W.; Xu, Y.; Yanez, J. P.; Yodh, G.; Yoshida, S.; Zoll, M.
2017-03-01
The IceCube Neutrino Observatory is a cubic-kilometer-scale high-energy neutrino detector built into the ice at the South Pole. Construction of IceCube, the largest neutrino detector built to date, was completed in 2011 and enabled the discovery of high-energy astrophysical neutrinos. We describe here the design, production, and calibration of the IceCube digital optical module (DOM), the cable systems, computing hardware, and our methodology for drilling and deployment. We also describe the online triggering and data filtering systems that select candidate neutrino and cosmic ray events for analysis. Due to a rigorous pre-deployment protocol, 98.4% of the DOMs in the deep ice are operating and collecting data. IceCube routinely achieves a detector uptime of 99% by emphasizing software stability and monitoring. Detector operations have been stable since construction was completed, and the detector is expected to operate at least until the end of the next decade.
POCA Update: An NSF PAARE Project
NASA Astrophysics Data System (ADS)
Walter, Donald K.; Brittain, S. D.; Cash, J. L.; Hartmann, D. H.; Howell, S. B.; King, J. R.; Leising, M. D.; Mayo, E. A.; Mighell, K. J.; Smith, D. M., Jr.
2011-01-01
We report on the status of "A Partnership in Observational and Computational Astronomy (POCA)” under the NSF's "Partnerships in Astronomy and Astrophysics Research and Education (PAARE)" program. This partnership includes South Carolina State University (a Historically Black College/University), Clemson University (a Ph.D. granting institution) and the National Optical Astronomy Observatory. We have reached the midpoint of this 5-year award and discuss the successes, challenges and obstacles encountered to date. Included is a summary of our summer REU program, the POCA graduate fellowship program, faculty research capacity building, outreach activities, increased use of NSF facilities and shared resources. Additional POCA research presentations by the authors are described elsewhere in these proceedings. Support for this work was provided by the NSF PAARE program to South Carolina State University under award AST-0750814 as well as resources and support provided by Clemson University and the National Optical Astronomy Observatory.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Abreu, P.; /Lisbon, IST; Aglietta, M.
2011-11-01
We present the results of an analysis of data recorded at the Pierre Auger Observatory in which we search for groups of directionally-aligned events (or ''multiplets'') which exhibit a correlation between arrival direction and the inverse of the energy. These signatures are expected from sets of events coming from the same source after having been deflected by intervening coherent magnetic fields. The observation of several events from the same source would open the possibility to accurately reconstruct the position of the source and also measure the integral of the component of the magnetic field orthogonal to the trajectory of themore » cosmic rays. We describe the largest multiplets found and compute the probability that they appeared by chance from an isotropic distribution. We find no statistically significant evidence for the presence of multiplets arising from magnetic deflections in the present data.« less
NASA Technical Reports Server (NTRS)
Ketchum, E.
1988-01-01
The Goddard Space Flight Center (GSFC) Flight Dynamics Division (FDD) will be responsible for performing ground attitude determination for Gamma Ray Observatory (GRO) support. The study reported in this paper provides the FDD and the GRO project with ground attitude determination error information and illustrates several uses of the Generalized Calibration System (GCS). GCS, an institutional software tool in the FDD, automates the computation of the expected attitude determination uncertainty that a spacecraft will encounter during its mission. The GRO project is particularly interested in the uncertainty in the attitude determination using Sun sensors and a magnetometer when both star trackers are inoperable. In order to examine the expected attitude errors for GRO, a systematic approach was developed including various parametric studies. The approach identifies pertinent parameters and combines them to form a matrix of test runs in GCS. This matrix formed the basis for this study.
Measuring surface flow velocity with smartphones: potential for citizen observatories
NASA Astrophysics Data System (ADS)
Weijs, Steven V.; Chen, Zichong; Brauchli, Tristan; Huwald, Hendrik
2014-05-01
Stream flow velocity is an important variable for discharge estimation and research on sediment dynamics. Given the influence of the latter on rating curves (stage-discharge relations), and the relative scarcity of direct streamflow measurements, surface velocity measurements can offer important information for, e.g., flood warning, hydropower, and hydrological science and engineering in general. With the growing amount of sensing and computing power in the hands of more outdoorsy individuals, and the advances in image processing techniques, there is now a tremendous potential to obtain hydrologically relevant data from motivated citizens. This is the main focus of the interdisciplinary "WeSenseIt" project, a citizen observatory of water. In this subproject, we investigate the feasibility of stream flow surface velocity measurements from movie clips taken by (smartphone-) cameras. First results from movie-clip derived velocity information will be shown and compared to reference measurements.
The Lifferth Dome for Small Telescopes
NASA Astrophysics Data System (ADS)
Wilson, B. L.; Olsen, C. S.; Iverson, E. P.; Paget, A.; Lifferth, W.; Brown, P. J.; Moody, J. W.
2004-12-01
The Lifferth Dome is a pull-off roof designed for small telescopes and other observational equipment. It was specifically designed for the needs of the ROVOR project. The roof itself is completely removed from the observatory housing walls and cranked off to the side below the optical horizon. This is done using two swing arms on either side of the observatory that work in unison to lift the roof off the structure and rotate down and away into a cleared location. The torque is provided by a threaded rod connected to an electric motor at the back of the building. As the motor rotates, the threads turn through a threaded sleeve connected directly to the support arms. Advantages to this design are no lost horizon, no roller surfaces to keep clean, low power and simple limit switches. Operation is by computer control using by National Instruments LabVIEW via the internet. We present its design and construction.
IceProd 2: A Next Generation Data Analysis Framework for the IceCube Neutrino Observatory
NASA Astrophysics Data System (ADS)
Schultz, D.
2015-12-01
We describe the overall structure and new features of the second generation of IceProd, a data processing and management framework. IceProd was developed by the IceCube Neutrino Observatory for processing of Monte Carlo simulations, detector data, and analysis levels. It runs as a separate layer on top of grid and batch systems. This is accomplished by a set of daemons which process job workflow, maintaining configuration and status information on the job before, during, and after processing. IceProd can also manage complex workflow DAGs across distributed computing grids in order to optimize usage of resources. IceProd is designed to be very light-weight; it runs as a python application fully in user space and can be set up easily. For the initial completion of this second version of IceProd, improvements have been made to increase security, reliability, scalability, and ease of use.
NASA Astrophysics Data System (ADS)
Sarazin, Marc S.; Osborn, James; Chacon-Oelckers, Arlette; Dérie, Frédéric J.; Le Louarn, Miska; Milli, Julien; Navarrete, Julio; Wilson, Richard R. W.
2017-09-01
The Stereo-SCIDAR (Scintillation Detection and Ranging) atmospheric turbulence profiler, built for ESO by Durham University, observes the scintillation patterns of binary elements with one of the four VLT-Interferometer 1.8m auxiliary telescopes at the ESO Paranal Observatory. The primary products are the vertical profiles of the index of refraction structure coefficient and of the wind velocity which allow to compute the wavefront coherence time and the isoplanatic angle with a vertical resolution of 250m. The several thousands of profiles collected during more than 30 nights of operation are grouped following criteria based on the altitude distribution or on principal component analysis. A set of reference profiles representative of the site is proposed as input for the various simulation models developed by the E-ELT (European Extremely Large Telescope) instruments Consortia.
Orbit Determination and Navigation of the Solar Terrestrial Relations Observatory (STEREO)
NASA Technical Reports Server (NTRS)
Mesarch, Michael A.; Robertson, Mika; Ottenstein, Neil; Nicholson, Ann; Nicholson, Mark; Ward, Douglas T.; Cosgrove, Jennifer; German, Darla; Hendry, Stephen; Shaw, James
2007-01-01
This paper provides an overview of the required upgrades necessary for navigation of NASA's twin heliocentric science missions, Solar TErestrial RElations Observatory (STEREO) Ahead and Behind. The orbit determination of the STEREO spacecraft was provided by the NASA Goddard Space Flight Center's (GSFC) Flight Dynamics Facility (FDF) in support of the mission operations activities performed by the Johns Hopkins University Applied Physics Laboratory (APL). The changes to FDF's orbit determination software included modeling upgrades as well as modifications required to process the Deep Space Network X-band tracking data used for STEREO. Orbit results as well as comparisons to independently computed solutions are also included. The successful orbit determination support aided in maneuvering the STEREO spacecraft, launched on October 26, 2006 (00:52 Z), to target the lunar gravity assists required to place the spacecraft into their final heliocentric drift-away orbits where they are providing stereo imaging of the Sun.
Orbit Determination and Navigation of the Solar Terrestrial Relations Observatory (STEREO)
NASA Technical Reports Server (NTRS)
Mesarch, Michael; Robertson, Mika; Ottenstein, Neil; Nicholson, Ann; Nicholson, Mark; Ward, Douglas T.; Cosgrove, Jennifer; German, Darla; Hendry, Stephen; Shaw, James
2007-01-01
This paper provides an overview of the required upgrades necessary for navigation of NASA's twin heliocentric science missions, Solar TErestrial RElations Observatory (STEREO) Ahead and Behind. The orbit determination of the STEREO spacecraft was provided by the NASA Goddard Space Flight Center's (GSFC) Flight Dynamics Facility (FDF) in support of the mission operations activities performed by the Johns Hopkins University Applied Physics Laboratory (APL). The changes to FDF s orbit determination software included modeling upgrades as well as modifications required to process the Deep Space Network X-band tracking data used for STEREO. Orbit results as well as comparisons to independently computed solutions are also included. The successful orbit determination support aided in maneuvering the STEREO spacecraft, launched on October 26, 2006 (00:52 Z), to target the lunar gravity assists required to place the spacecraft into their final heliocentric drift-away orbits where they are providing stereo imaging of the Sun.
Monitoring non-periodic comet C/2011 L4 PANSTARRS using Joan Oró 0.8 m robotic telescope at OAdM
NASA Astrophysics Data System (ADS)
Trigo-Rodríguez, J. M.; Rodríguez, D.; Lacruz, J.; Sánchez, A.
2013-09-01
Comet C/2011 L4 PANSTARRS was discovered in June 2011 by R. Wainscoat and D. Tholen using the Pan-STARRS telescope located near the summit of Haleakala, on the island of Maui in Hawaii (USA) [1]. Once its orbit was computed it was noticed its non-periodic nature and the favorable geometry during its approach to perihelion in March 2013. It first became visible to the naked eye from the Southern hemisphere, and later on it started to be seen during mid-March from the Northern one. Due to the limited observational period in right conditions we introduce here some observations obtained taken from robotic 0.8 m Telescope Joan Oró (JO) from the Observatori Astronòmic del Montsec (OAdM: www.oadm.cat) and other Spanish observatories.
Two-Flux and Green's Function Method for Transient Radiative Transfer in a Semi-Transparent Layer
NASA Technical Reports Server (NTRS)
Siegel, Robert
1995-01-01
A method using a Green's function is developed for computing transient temperatures in a semitransparent layer by using the two-flux method coupled with the transient energy equation. Each boundary of the layer is exposed to a hot or cold radiative environment, and is heated or cooled by convection. The layer refractive index is larger than one, and the effect of internal reflections is included with the boundaries assumed diffuse. The analysis accounts for internal emission, absorption, heat conduction, and isotropic scattering. Spectrally dependent radiative properties are included, and transient results are given to illustrate two-band spectral behavior with optically thin and thick bands. Transient results using the present Green's function method are verified for a gray layer by comparison with a finite difference solution of the exact radiative transfer equations; excellent agreement is obtained. The present method requires only moderate computing times and incorporates isotropic scattering without additional complexity. Typical temperature distributions are given to illustrate application of the method by examining the effect of strong radiative heating on one side of a layer with convective cooling on the other side, and the interaction of strong convective heating with radiative cooling from the layer interior.
Breakthrough Listen - A New Search for Life in the Universe
NASA Astrophysics Data System (ADS)
Worden, Pete
On July 20, 2015 Yuri Milner and Stephen Hawking announced a new set of scientific initiatives - a SETI search called Breakthrough Listen and a contest to devise potential messages in response to a detection entitled Breakthrough Message. These are the first of several privately-funded Breakthrough Initiatives, designed to answer the fundamental science questions surrounding the origin, extent and nature of life in the universe. The initiatives are managed by the Breakthrough Prize Foundation. With Breakthrough Listen, Radio SETI observations have begun at the Green Bank Radio Telescope (GBT) and optical SETI at the Lick Observatory Automated Planet Finder (APF). Observations will soon commence at the CSIRO Parkes Radio Telescope. Other SETI instruments and observations are under consideration. In addition, several other initiatives are under development including an expanded search for life in the universe.
Multiwavelength Study Of The Large Radio Feature SNR G106.3+2.7 Using SUZAKU, LAT , VERITAS And GBT
NASA Astrophysics Data System (ADS)
Aliu, Ester; Gotthelf, E.; Wakely, S.; Hewitt, J.
2011-09-01
SNR G106.3+2.7 is a degree-scale radio supernova remnant with an energetic pulsar (PSR J2229+6114) near its northeastern end that lies within a small ( arcmin) Boomerang radio shell, likely a SNR. It has been proposed that the two SNR resulted from the same supernova explosion. The recent discovery of TeV gamma-ray emission well beyond the pulsar, near the center of SNR G106.3+2.7 challenges this picture. We report on our multiwavelength study of the region SNR G106.3+2.7 with the SUZAKU X-ray observatory, Fermi Gamma-ray telecope, and Green Bank radio telescope, to search for masers. Mapping of the SNR with SUZAKU has located possible counterparts to the TeV gamma-ray emission.
Pandora Cluster Seen by Spitzer
2016-09-28
This image of galaxy cluster Abell 2744, also called Pandora's Cluster, was taken by the Spitzer Space Telescope. The gravity of this galaxy cluster is strong enough that it acts as a lens to magnify images of more distant background galaxies. This technique is called gravitational lensing. The fuzzy blobs in this Spitzer image are the massive galaxies at the core of this cluster, but astronomers will be poring over the images in search of the faint streaks of light created where the cluster magnifies a distant background galaxy. The cluster is also being studied by NASA's Hubble Space Telescope and Chandra X-Ray Observatory in a collaboration called the Frontier Fields project. In this image, light from Spitzer's infrared channels is colored blue at 3.6 microns and green at 4.5 microns. http://photojournal.jpl.nasa.gov/catalog/PIA20920
Zhang, Guanglei; Liu, Fei; Zhang, Bin; He, Yun; Luo, Jianwen; Bai, Jing
2013-04-01
Pharmacokinetic rates have the potential to provide quantitative physiological and pathological information for biological studies and drug development. Fluorescence molecular tomography (FMT) is an attractive imaging tool for three-dimensionally resolving fluorophore distribution in small animals. In this letter, pharmacokinetic rates of indocyanine green (ICG) in mouse liver are imaged with a hybrid FMT and x-ray computed tomography (XCT) system. A recently developed FMT method using structural priors from an XCT system is adopted to improve the quality of FMT reconstruction. In the in vivo experiments, images of uptake and excretion rates of ICG in mouse liver are obtained, which can be used to quantitatively evaluate liver function. The accuracy of the results is validated by a fiber-based fluorescence measurement system.
The Application of High Energy Resolution Green's Functions to Threat Scenario Simulation
NASA Astrophysics Data System (ADS)
Thoreson, Gregory G.; Schneider, Erich A.
2012-04-01
Radiation detectors installed at key interdiction points provide defense against nuclear smuggling attempts by scanning vehicles and traffic for illicit nuclear material. These hypothetical threat scenarios may be modeled using radiation transport simulations. However, high-fidelity models are computationally intensive. Furthermore, the range of smuggler attributes and detector technologies create a large problem space not easily overcome by brute-force methods. Previous research has demonstrated that decomposing the scenario into independently simulated components using Green's functions can simulate photon detector signals with coarse energy resolution. This paper extends this methodology by presenting physics enhancements and numerical treatments which allow for an arbitrary level of energy resolution for photon transport. As a result, spectroscopic detector signals produced from full forward transport simulations can be replicated while requiring multiple orders of magnitude less computation time.
Banerjee, Sourav; Kundu, Tribikram
2008-03-01
Multilayered solid structures made of isotropic, transversely isotropic, or general anisotropic materials are frequently used in aerospace, mechanical, and civil structures. Ultrasonic fields developed in such structures by finite size transducers simulating actual experiments in laboratories or in the field have not been rigorously studied. Several attempts to compute the ultrasonic field inside solid media have been made based on approximate paraxial methods like the classical ray tracing and multi-Gaussian beam models. These approximate methods have several limitations. A new semianalytical method is adopted in this article to model elastic wave field in multilayered solid structures with planar or nonplanar interfaces generated by finite size transducers. A general formulation good for both isotropic and anisotropic solids is presented in this article. A variety of conditions have been incorporated in the formulation including irregularities at the interfaces. The method presented here requires frequency domain displacement and stress Green's functions. Due to the presence of different materials in the problem geometry various elastodynamic Green's functions for different materials are used in the formulation. Expressions of displacement and stress Green's functions for isotropic and anisotropic solids as well as for the fluid media are presented. Computed results are verified by checking the stress and displacement continuity conditions across the interface of two different solids of a bimetal plate and investigating if the results for a corrugated plate with very small corrugation match with the flat plate results.
Computer vision applications for coronagraphic optical alignment and image processing.
Savransky, Dmitry; Thomas, Sandrine J; Poyneer, Lisa A; Macintosh, Bruce A
2013-05-10
Modern coronagraphic systems require very precise alignment between optical components and can benefit greatly from automated image processing. We discuss three techniques commonly employed in the fields of computer vision and image analysis as applied to the Gemini Planet Imager, a new facility instrument for the Gemini South Observatory. We describe how feature extraction and clustering methods can be used to aid in automated system alignment tasks, and also present a search algorithm for finding regular features in science images used for calibration and data processing. Along with discussions of each technique, we present our specific implementation and show results of each one in operation.
NASA Technical Reports Server (NTRS)
Thompson, T. W.; Cutts, J. A.
1981-01-01
A catalog of lunar and radar anomalies was generated to provide a base for comparison with Venusian radar signatures. The relationships between lunar radar anomalies and regolith processes were investigated, and a consortium was formed to compare lunar and Venusian radar images of craters. Time was scheduled at the Arecibo Observatory to use the 430 MHz radar to obtain high resolution radar maps of six areas of the lunar suface. Data from 1978 observations of Mare Serenitas and Plato are being analyzed on a PDP 11/70 computer to construct the computer program library necessary for the eventual reduction of the May 1981 and subsequent data acquisitions. Papers accepted for publication are presented.
Application of an onboard processor to the OAO C spacecraft
NASA Technical Reports Server (NTRS)
Stewart, W. N.; Hartenstein, R. G.; Trevathan, C.
1972-01-01
The design of a stored program computer for spacecraft use and its application on the fourth Orbiting Astronomical Observatory (OAO) is reported. The computer is a medium scale, parallel machine with a memory capacity of 16384 words of 18 bits each. It possesses a comprehensive instruction repertoire and operates on 45 W of power (including the dc-to-dc converter). The machine operates at a 500-kHz rate and executes an add instruction in 10 microseconds. Its primary functions on OAO C will be auxiliary command storage, spacecraft monitoring and malfunction reporting, data compression and status summary, and possible performance of emergency corrective action for certain anomalous situations.
Assessing the Amazon Cloud Suitability for CLARREO's Computational Needs
NASA Technical Reports Server (NTRS)
Goldin, Daniel; Vakhnin, Andrei A.; Currey, Jon C.
2015-01-01
In this document we compare the performance of the Amazon Web Services (AWS), also known as Amazon Cloud, with the CLARREO (Climate Absolute Radiance and Refractivity Observatory) cluster and assess its suitability for computational needs of the CLARREO mission. A benchmark executable to process one month and one year of PARASOL (Polarization and Anistropy of Reflectances for Atmospheric Sciences coupled with Observations from a Lidar) data was used. With the optimal AWS configuration, adequate data-processing times, comparable to the CLARREO cluster, were found. The assessment of alternatives to the CLARREO cluster continues and several options, such as a NASA-based cluster, are being considered.
Custom blending of lamp phosphors
NASA Technical Reports Server (NTRS)
Klemm, R. E.
1978-01-01
Spectral output of fluorescent lamps can be precisely adjusted by using computer-assisted analysis for custom blending lamp phosphors. With technique, spectrum of main bank of lamps is measured and stored in computer memory along with emission characteristics of commonly available phosphors. Computer then calculates ratio of green and blue intensities for each phosphor according to manufacturer's specifications and plots them as coordinates on graph. Same ratios are calculated for measured spectrum. Once proper mix is determined, it is applied as coating to fluorescent tubing.
Seismic instrumentation plan for the Hawaiian Volcano Observatory
Thelen, Weston A.
2014-01-01
The installation of new seismic stations is only the first part of building a volcanic early warning capability for seismicity in the State of Hawaii. Additional personnel will likely be required to study the volcanic processes at work under each volcano, analyze the current seismic activity at a level sufficient for early warning, build new tools for monitoring, maintain seismic computing resources, and maintain the new seismic stations.
NASA Technical Reports Server (NTRS)
1995-01-01
Software Bisque's TheSky, SkyPro and Remote Astronomy Software incorporate technology developed for the Hubble Space Telescope. TheSky and SkyPro work together to orchestrate locating, identifying and acquiring images of deep sky objects. With all three systems, the user can directly control computer-driven telescopes and charge coupled device (CCD) cameras through serial ports. Through the systems, astronomers and students can remotely operate a telescope at the Mount Wilson Observatory Institute.
Efficient and automatic image reduction framework for space debris detection based on GPU technology
NASA Astrophysics Data System (ADS)
Diprima, Francesco; Santoni, Fabio; Piergentili, Fabrizio; Fortunato, Vito; Abbattista, Cristoforo; Amoruso, Leonardo
2018-04-01
In the last years, the increasing number of space debris has triggered the need of a distributed monitoring system for the prevention of possible space collisions. Space surveillance based on ground telescope allows the monitoring of the traffic of the Resident Space Objects (RSOs) in the Earth orbit. This space debris surveillance has several applications such as orbit prediction and conjunction assessment. In this paper is proposed an optimized and performance-oriented pipeline for sources extraction intended to the automatic detection of space debris in optical data. The detection method is based on the morphological operations and Hough Transform for lines. Near real-time detection is obtained using General Purpose computing on Graphics Processing Units (GPGPU). The high degree of processing parallelism provided by GPGPU allows to split data analysis over thousands of threads in order to process big datasets with a limited computational time. The implementation has been tested on a large and heterogeneous images data set, containing both imaging satellites from different orbit ranges and multiple observation modes (i.e. sidereal and object tracking). These images were taken during an observation campaign performed from the EQUO (EQUatorial Observatory) observatory settled at the Broglio Space Center (BSC) in Kenya, which is part of the ASI-Sapienza Agreement.
NASA Technical Reports Server (NTRS)
Koschny, D.; Gritsevich, M.; Barentsen, G.
2011-01-01
Different authors have produced models for the physical properties of meteoroids based on the shape of a meteor's light curve, typically from short observing campaigns. We here analyze the height profiles and light curves of approx.200 double-station meteors from the Leonids and Perseids using data from the Virtual Meteor Observatory, to demonstrate that with this web-based meteor database it is possible to analyze very large datasets from different authors in a consistent way. We compute the average heights for begin point, maximum luminosity, and end heights for Perseids and Leonids. We also compute the skew of the light curve, usually called the F-parameter. The results compare well with other author's data. We display the average light curve in a novel way to assess the light curve shape in addition to using the F-parameter. While the Perseids show a peaked light curve, the average Leonid light curve has a more flat peak. This indicates that the particle distribution of Leonid meteors can be described by a Gaussian distribution; the Perseids can be described with a power law. The skew for Leonids is smaller than for Perseids, indicating that the Leonids are more fragile than the Perseids.
NASA Astrophysics Data System (ADS)
Smits, D. P.
2007-07-01
In 1873, the University of the Cape of Good Hope, an examining body with the power to grant degrees, was established in Cape Town. In Act 12 of 1916, it was transformed into a new federal university, effective from 02 April 1918. The name of the institution was changed to the University of South Africa (Unisa) and its headquarters was moved to Pretoria. In response to pressure from unattached students from all races to obtain qualifications without attendance at a university or college, in 1947 Unisa started teaching some subjects internally. With over 200 000 students registered in distance degree programmes in 2005, Unisa is the largest tertiary education institution on the African continent. Examinations are arranged at centres conveniently located throughout the world. Astronomy has been offered at Unisa since 1923. In 1960 Mr J Wolterbeek was appointed as the first full-time lecturer in Astronomy, and in 1972 the 9-inch Reunert Telescope, donated to Unisa by the Republic Observatory, was installed in a roof-top observatory on the new Theo van Wyk building on Mucklneuk Ridge. A new observatory, containing a 14-inch computer-controlled Schmidt-Cassegrain reflector, was inaugurated in 1992. Unisa currently offers a BSc major in Astronomy, post-graduate tuition up to the PhD level and is part of the National Astrophysics and Space Science Programme (NASSP) consortium.
AstroCloud, a Cyber-Infrastructure for Astronomy Research: Cloud Computing Environments
NASA Astrophysics Data System (ADS)
Li, C.; Wang, J.; Cui, C.; He, B.; Fan, D.; Yang, Y.; Chen, J.; Zhang, H.; Yu, C.; Xiao, J.; Wang, C.; Cao, Z.; Fan, Y.; Hong, Z.; Li, S.; Mi, L.; Wan, W.; Wang, J.; Yin, S.
2015-09-01
AstroCloud is a cyber-Infrastructure for Astronomy Research initiated by Chinese Virtual Observatory (China-VO) under funding support from NDRC (National Development and Reform commission) and CAS (Chinese Academy of Sciences). Based on CloudStack, an open source software, we set up the cloud computing environment for AstroCloud Project. It consists of five distributed nodes across the mainland of China. Users can use and analysis data in this cloud computing environment. Based on GlusterFS, we built a scalable cloud storage system. Each user has a private space, which can be shared among different virtual machines and desktop systems. With this environments, astronomer can access to astronomical data collected by different telescopes and data centers easily, and data producers can archive their datasets safely.
Cloud@Home: A New Enhanced Computing Paradigm
NASA Astrophysics Data System (ADS)
Distefano, Salvatore; Cunsolo, Vincenzo D.; Puliafito, Antonio; Scarpa, Marco
Cloud computing is a distributed computing paradigm that mixes aspects of Grid computing, ("… hardware and software infrastructure that provides dependable, consistent, pervasive, and inexpensive access to high-end computational capabilities" (Foster, 2002)) Internet Computing ("…a computing platform geographically distributed across the Internet" (Milenkovic et al., 2003)), Utility computing ("a collection of technologies and business practices that enables computing to be delivered seamlessly and reliably across multiple computers, ... available as needed and billed according to usage, much like water and electricity are today" (Ross & Westerman, 2004)) Autonomic computing ("computing systems that can manage themselves given high-level objectives from administrators" (Kephart & Chess, 2003)), Edge computing ("… provides a generic template facility for any type of application to spread its execution across a dedicated grid, balancing the load …" Davis, Parikh, & Weihl, 2004) and Green computing (a new frontier of Ethical computing1 starting from the assumption that in next future energy costs will be related to the environment pollution).
NASA Astrophysics Data System (ADS)
Khomutov, Sergey Y.
2017-10-01
Continuous magnetic measurements at Geophysical Observatory "Paratunka" (PET) of IKIR FEB RAS are performed since 1967. In the new millennium analogue magnetometers were modernized to digital, the technologies of absolute observations were changed, the data processing was completely transferred to computers, and the status of INTERMAGNET observatory was obtained. Currently, the observatory uses the following magnetometers: (a) for absolute observations - DIflux LEMI-203 (theodolite 3T2KP) and Mag-01 (theodolite Wild-T1), Overhauser magnetometers POS-1 and GSM-19W; (b) for variation measurements - fluxgate magnetometers FGE-DTU, FRG-601 and MAGDAS (installed under international agreements of IKIR), vector magnetometers dIdD GSM-19FD and POS-4 with Overhauser sensors and coil systems, scalar magnetometer GSM-90 and induction magnetometer STELAB. During Spring-Autumn season dIdD also is installed at remote station "Karymshina" at distance of 15 km from Observatory. There is monitoring system for monitoring of conditions in which magnetic observations are performed, including the semi-professional weather stations Davis Vantage Pro2 and WS2000 and a network of digital temperature sensors DS19B20 located at various points in magnetic pavilions and outdoor. All measurements are synchronized with the UTC. The results of observations are collected by the IKIR data server from the recorders and loggers, including in real-time. Specialized software was developed (based on MATLAB and Octave packages), which allows automatic and semi-automatic processing of data, the comparison of the results from different magnetometers and presenting final data in formats, defined by international standards, including INTERMAGNET. Significant efforts of observatory staff are direct to archive (raw) magnetic data, a significant part of which has not been entirely processed, is not presented in international data centers and is still not available to the scientific community. Digital images of analog magnetograms have been obtained, the digitization of which allowed to fill the gaps in the hourly data available in the WDC for 1991, 1996-1997. The state of the set of the instruments and databases shows that the observatory "Paratunka" can solve most of the problems that arise in the geomagnetic field researches, including the provision of data for the development of regional and global field models, ground support of magnetometers located on satellites, support of the surface (sea) and aeromagnetic surveys and drilling, providing the data for researches of processes in the lithosphere, magnetosphere and ionosphere over a wide frequency range, and also for a number of applied problems. ARRAY(0x189e680)
NASA Astrophysics Data System (ADS)
Kelbert, A.; Egbert, G. D.; Sun, J.
2011-12-01
Poleward of 45-50 degrees (geomagnetic) observatory data are influenced significantly by auroral ionospheric current systems, invalidating the simplifying zonal dipole source assumption traditionally used for long period (T > 2 days) geomagnetic induction studies. Previous efforts to use these data to obtain the global electrical conductivity distribution in Earth's mantle have omitted high-latitude sites (further thinning an already sparse dataset) and/or corrected the affected transfer functions using a highly simplified model of auroral source currents. Although these strategies are partly effective, there remain clear suggestions of source contamination in most recent 3D inverse solutions - specifically, bands of conductive features are found near auroral latitudes. We report on a new approach to this problem, based on adjusting both external field structure and 3D Earth conductivity to fit observatory data. As an initial step towards full joint inversion we are using a two step procedure. In the first stage, we adopt a simplified conductivity model, with a thin-sheet of variable conductance (to represent the oceans) overlying a 1D Earth, to invert observed magnetic fields for external source spatial structure. Input data for this inversion are obtained from frequency domain principal components (PC) analysis of geomagnetic observatory hourly mean values. To make this (essentially linear) inverse problem well-posed we regularize using covariances for source field structure that are consistent with well-established properties of auroral ionospheric (and magnetospheric) current systems, and basic physics of the EM fields. In the second stage, we use a 3D finite difference inversion code, with source fields estimated from the first stage, to further fit the observatory PC modes. We incorporate higher latitude data into the inversion, and maximize the amount of available information by directly inverting the magnetic field components of the PC modes, instead of transfer functions such as C-responses used previously. Recent improvements in accuracy and speed of the forward and inverse finite difference codes (a secondary field formulation and parallelization over frequencies) allow us to use finer computational grid for inversion, and thus to model finer scale features, making full use of the expanded data set. Overall, our approach presents an improvement over earlier observatory data interpretation techniques, making better use of the available data, and allowing to explore the trade-offs between complications in source structure, and heterogeneities in mantle conductivity. We will also report on progress towards applying the same approach to simultaneous source/conductivity inversion of shorter period observatory data, focusing especially on the daily variation band.
ESTCP Pilot Project Wide Area Assessment for Munitions Response
2008-07-01
Data A broadband normalized difference vegetation index ( NDVI ) was computed from the high- resolution spectral data to provide a detection of canopy...chlorophyll content. The NDVI strongly correlates with the green yucca, cactus, juniper, and other SAR-responsive vegetation species on the site...Vegetation Index. NDVI is broadband normalized difference vegetation index computed from high resolution spectral data using (RED-NIR) / (RED +NIR) to
Pinch technique and the Batalin-Vilkovisky formalism
NASA Astrophysics Data System (ADS)
Binosi, Daniele; Papavassiliou, Joannis
2002-07-01
In this paper we take the first step towards a nondiagrammatic formulation of the pinch technique. In particular we proceed into a systematic identification of the parts of the one-loop and two-loop Feynman diagrams that are exchanged during the pinching process in terms of unphysical ghost Green's functions; the latter appear in the standard Slavnov-Taylor identity satisfied by the tree-level and one-loop three-gluon vertex. This identification allows for the consistent generalization of the intrinsic pinch technique to two loops, through the collective treatment of entire sets of diagrams, instead of the laborious algebraic manipulation of individual graphs, and sets up the stage for the generalization of the method to all orders. We show that the task of comparing the effective Green's functions obtained by the pinch technique with those computed in the background field method Feynman gauge is significantly facilitated when employing the powerful quantization framework of Batalin and Vilkovisky. This formalism allows for the derivation of a set of useful nonlinear identities, which express the background field method Green's functions in terms of the conventional (quantum) ones and auxiliary Green's functions involving the background source and the gluonic antifield; these latter Green's functions are subsequently related by means of a Schwinger-Dyson type of equation to the ghost Green's functions appearing in the aforementioned Slavnov-Taylor identity.
Color vision testing with a computer graphics system: preliminary results.
Arden, G; Gündüz, K; Perry, S
1988-06-01
We report a method for computer enhancement of color vision tests. In our graphics system 256 colors are selected from a much larger range and displayed on a screen divided into 768 x 288 pixels. Eight-bit digital-to-analogue converters drive a high quality monitor with separate inputs to the red, green, and blue amplifiers and calibrated gun chromaticities. The graphics are controlled by a PASCAL program written for a personal computer, which calculates the values of the red, green, and blue signals and specifies them in Commité Internationale d'Eclairage X, Y, and Z fundamentals, so changes in chrominance occur without changes in luminance. The system for measuring color contrast thresholds with gratings is more than adequate in normal observers. In patients with mild retinal damage in whom other tests of visual function are normal, this method of testing color vision shows specific increases in contrast thresholds along tritan color-confusion lines. By the time the Hardy-Rand-Rittler and Farnsworth-Munsell 100-hue tests disclose abnormalities, gross defects in color contrast threshold can be seen with our system.
1999-05-01
substitution of the second leucine in an LxxLL core with isoleucine still permits a strong hydrophobic interaction with the liganded receptor (Table 2...through electrostatic interactions. Figure 10 illustrates that the two leucines and one isoleucine (green and cyan) of the LxxlL motif are predicted to be...RARox was carried out as described in Materials and methods. The side chains of the two leucines (green) and one isoleucine (cyan) of the LxxIL core fit
Solvent replacement for green processing.
Sherman, J; Chin, B; Huibers, P D; Garcia-Valls, R; Hatton, T A
1998-01-01
The implementation of the Montreal Protocol, the Clean Air Act, and the Pollution Prevention Act of 1990 has resulted in increased awareness of organic solvent use in chemical processing. The advances made in the search to find "green" replacements for traditional solvents are reviewed, with reference to solvent alternatives for cleaning, coatings, and chemical reaction and separation processes. The development of solvent databases and computational methods that aid in the selection and/or design of feasible or optimal environmentally benign solvent alternatives for specific applications is also discussed. Images Figure 2 Figure 3 PMID:9539018
When Will It Be …?: U.S. Naval Observatory Calendar Computers
NASA Astrophysics Data System (ADS)
Bartlett, Jennifer L.; Chizek Frouard, Malynda; Lesniak, Michael V.
2016-06-01
Sensitivity to religious calendars is increasingly expected when planning activities. Consequently, the U.S. Naval Observatory (USNO) has redesigned its on-line calendar resources to allow the computation of select religious dates for specific years via an application programming interface (API). This flexible interface returns dates in JavaScript Object Notation (JSON) that can be incorporated into third-party websites or applications. Currently, the services compute Christian, Islamic, and Jewish events.The “Dates of Ash Wednesday and Easter” service (http://aa.usno.navy.mil/data/docs/easter.php) returns the dates of these two events for years after 1582 C.E. (1582 A.D.) The method of the western Christian churches is used to determined when Easter, a moveable feast, occurs.The “Dates of Islamic New Year and Ramadan” service (http://aa.usno.navy.mil/data/docs/islamic.php) returns the approximate Gregorian dates of these two events for years after 1582 C.E. (990 A.H.) and Julian dates are computed for the years 622-1582 C.E. (1-990 A.H.). The appropriate year in the Islamic calendar (anno Hegira) is also provided. Each event begins at 6 P.M. or sunset on the preceding day. These events are computed using a tabular calendar for planning purposes; in practice, the actual event is determined by observation of the appropriate new Moon.The “First Day of Passover” service (http://aa.usno.navy.mil/data/docs/passover.php) returns the Gregorian date corresponding to Nisan 15 for years after 1582 C.E. (5342 A.M.) and Julian dates are computed for the years 360-1582 C.E. (4120-5342 A.M.). The appropriate year in the Jewish calendar (anno Mundi) is also provided. Passover begins at 6 P.M. or sunset on the preceding day.On-line documentation for using the API-enabled calendar computers, including sample calls, is available (http://aa.usno.navy.mil/data/docs/api.php). The same web page also describes how to reach the Complete Sun and Moon Data for One Day, Phases of the Moon, Solar Eclipse Computer, Day and Night Across the Earth, and Apparent Disk of a Solar System Object services using API calls.An “Introduction to Calendars” (http://aa.usno.navy.mil/faq/docs/calendars.php) provides an overview of the topic and links to additional resources.
Kitagawa, Hiroyuki; Namikawa, Tsutomu; Iwabu, Jun; Hanazaki, Kazuhiro
2017-01-01
We report a case of gastric tube reconstruction with superdrainage using indocyanine green fluorescence during esophagectomy for esophageal cancer. A 53-year-old man with a history of early esophageal cancer treated with endoscopic mucosal dissection experienced esophageal cancer recurrence. There was no evidence of lymph node involvement or distant metastasis on computed tomography; therefore, we performed thoracoscopic esophagectomy. After thoracoscopic esophagectomy, we created a gastric tube. When pulling up the gastric tube through the post-mediastinum route, a root of the right gastroepiploic vein was injured. We subsequently performed superdrainage to avoid congestion of the gastric tube with omental vein and pre-tracheal vein anastomosis at the neck, and confirmed venous flow using the indocyanine green fluorescence method. No postoperative anastomotic leakage was observed, and the patient was discharged 22 days after surgery. Thus, we recommend the indocyanine green fluorescence method in cases involving superdrainage during esophagectomy. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.