Institution
Raytheon
Company•Waltham, Massachusetts, United States•
About: Raytheon is a company organization based out in Waltham, Massachusetts, United States. It is known for research contribution in the topics: Signal & Antenna (radio). The organization has 15290 authors who have published 18973 publications receiving 300052 citations.
Topics: Signal, Antenna (radio), Radar, Layer (electronics), Turbine
Papers published on a yearly basis
Papers
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TL;DR: In this article, a theory of ferromagnetic resonance is developed in which dipolar interaction is taken into account by means of the spin-wave formalism, and the moments of the absorption line are calculated for vanishingly small single-crystal linewidths.
192 citations
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09 Jul 2007TL;DR: In this paper, the authors present a web-based application for displaying a map that includes a particular geographical location, retrieving at least one of a plurality of data records from the metadata database, and displaying the at most one data record at the particular location of the map for a user.
Abstract: In one embodiment, a geographical information system has an information database and a client computing system that is coupled to a web server. A web based application is operable to display a map that includes a particular geographical location, retrieve at least one of a plurality of data records from the metadata database, and display the at least one data record at the particular geographical location of the map for a user. The web based application is executable on the client computing system or on the web server using a web browser.
191 citations
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TL;DR: A number of special Baumert-Hall sets of units, including an infinite class, are constructed here; these give the densest known classes of Hadamard matrices.
191 citations
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Harvard University1, National Oceanic and Atmospheric Administration2, University of Chicago3, Goddard Space Flight Center4, Raytheon5, National Institute of Water and Atmospheric Research6, Deutscher Wetterdienst7, Royal Meteorological Institute8, Environment Canada9, ETH Zurich10, MeteoSwiss11, Japan Meteorological Agency12
TL;DR: In this article, the authors present the results of two independent analyses of ozonesonde measurements of the vertical profile of ozone and find significant decreases in stratospheric ozone at all stations in middle and high latitudes of the northern hemisphere from 1970 to 1996, with the largest decreases located between 12 and 21 km.
Abstract: We present the results of two independent analyses of ozonesonde measurements of the vertical profile of ozone. For most of the ozonesonde stations we use data that were recently reprocessed and reevaluated to improve their quality and internal consistency. The two analyses give similar results for trends in ozone. We attribute differences in results primarily to differences in data selection criteria and in utilization of data correction factors, rather than in statistical trend models. We find significant decreases in stratospheric ozone at all stations in middle and high latitudes of the northern hemisphere from 1970 to 1996, with the largest decreases located between 12 and 21 km, and trends of -3 to -10 %/decade near 17 km. The decreases are largest at the Canadian and the most northerly Japanese station, and are smallest at the European stations, and at Wallops Island, U.S.A. The mean mid-latitude trend is largest, -7 %/decade, from 12 to 17.5 km for 1970-96. For 1980-96, the decrease is more negative by 1-2 %/decade, with a maximum trend of -9 %/decade in the lowermost stratosphere. The trends vary seasonally from about 12 to 17.5 km, with largest ozone decreases in winter and spring. Trends in tropospheric ozone are highly variable and depend on region. There are decreases or zero trends at the Canadian stations for 1970-96, and decreases of -2 to -8 %/decade for the mid-troposphere for 1980-96; the three European stations show increases for 1970-96, but trends are close to zero for two stations for 1980-96 and positive for one; there are increases in ozone for the three Japanese stations for 1970-96, but trends are either positive or zero for 1980-96; the U.S. stations show zero or slightly negative trends in tropospheric ozone after 1980. It is not possible to define reliably a mean tropospheric ozone trend for northern mid-latitudes, given the small number of stations and the large variability in trends. The integrated column trends derived from the sonde data are consistent with trends derived from both surface based and satellite measurements of the ozone column.
190 citations
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TL;DR: In this article, the authors measured the duration of starbursts in twenty nearby, ongoing, and "fossil" starburst in dwarf galaxies based on the recent star formation histories derived from resolved stellar population data obtained with the Hubble Space Telescope and calculated that the bursts deposited 10 53.9 −10 57.2 erg of energy into the interstellar medium through stellar winds and supernovae, and produced 3%−26% of the host galaxy's mass.
Abstract: The starburst phenomenon can shape the evolution of the host galaxy and the surrounding intergalactic medium. The extent of the evolutionary impact is partly determined by the duration of the starburst, which has a direct correlation with both the amount of stellar feedback and the development of galactic winds, particularly for smaller mass dwarf systems. We measure the duration of starbursts in twenty nearby, ongoing, and “fossil” starbursts in dwarf galaxies based on the recent star formation histories derived from resolved stellar population data obtained with the Hubble Space Telescope. Contrary to the shorter times of 3–10 Myr often cited, the starburst durations we measure range from 450 to 650 Myr in fifteen of the dwarf galaxies and up to 1.3 Gyr in four galaxies; these longer durations are comparable to or longer than the dynamical timescales for each system. The same feedback from massive stars that may quench the flickering star formation does not disrupt the overall burst event in our sample of galaxies. While five galaxies present fossil bursts, fifteen galaxies show ongoing bursts and thus the final durations may be longer than we report here for these systems. One galaxy shows a burst that has been ongoing for only 20 Myr; we are likely seeing the beginning of a burst event in this system. Using the duration of the starbursts, we calculate that the bursts deposited 10 53.9 –10 57.2 erg of energy into the interstellar medium through stellar winds and supernovae, and produced 3%−26% of the host galaxy’s mass.
190 citations
Authors
Showing all 15293 results
Name | H-index | Papers | Citations |
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Peter J. Kahrilas | 109 | 586 | 46064 |
Edward J. Wollack | 104 | 732 | 102070 |
Duong Nguyen | 98 | 674 | 47332 |
Miroslav Krstic | 95 | 955 | 42886 |
Steven L. Suib | 89 | 862 | 34189 |
Gabriel M. Rebeiz | 87 | 806 | 32443 |
Charles W. Engelbracht | 83 | 210 | 28137 |
Paul A. Grayburn | 77 | 397 | 26880 |
Eric J. Huang | 72 | 201 | 22172 |
Thomas F. Eck | 72 | 150 | 32965 |
David M. Margolis | 70 | 227 | 17314 |
David W. T. Griffith | 65 | 288 | 14232 |
Gerhard Klimeck | 65 | 685 | 18447 |
Nickolay A. Krotkov | 63 | 219 | 11250 |
Olaf Stüve | 63 | 290 | 14268 |