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Journal articles on the topic 'NASA's Space Network (SN)'

Author: Grafiati

Published: 4 June 2021

Last updated: 3 February 2022

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1

Johnston, Mark D., Daniel Tran, Belinda Arroyo, et al. "Automated Scheduling for NASA's Deep Space Network." AI Magazine 35, no. 4 (2014): 7–25. http://dx.doi.org/10.1609/aimag.v35i4.2552.

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This article describes the DSN scheduling wngine (DSE) component of a new scheduling system being deployed for NASA's deep space network. The DSE provides core automation functionality for scheduling the network, including the interpretation of scheduling requirements expressed by users, their elaboration into tracking passes, and the resolution of conflicts and constraint violations. The DSE incorporates both systematic search and repair-based algorithms, used for different phases and purposes in the overall system. It has been integrated with a web application which provides DSE functionalit

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Teitelbaum, Lawrence, Walid Majid, Manuel M. Franco, Daniel J. Hoppe, Shinji Horiuchi, and T. Joseph W. Lazio. "Precision Pulsar Timing with NASA's Deep Space Network." Proceedings of the International Astronomical Union 11, A29B (2015): 367–69. http://dx.doi.org/10.1017/s174392131600555x.

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AbstractMillisecond pulsars (MSPs) are a class of radio pulsars with extremely stable rotation. Their excellent timing stability can be used to study a wide variety of astrophysical phenomena. In particular, a large sample of these pulsars can be used to detect low-frequency gravitational waves. We have developed a precision pulsar timing backend for the NASA Deep Space Network (DSN), which will allow the use of short gaps in tracking schedules to time pulses from an ensemble of MSPs. The DSN operates clusters of large dish antennas (up to 70-m in diameter), located roughly equidistant around

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Witkowski, Mona M., John Todd, and John Dokken. "4.1.2 Managing Risk in NASA's Deep Space Network." INCOSE International Symposium 21, no. 1 (2011): 342–57. http://dx.doi.org/10.1002/j.2334-5837.2011.tb01211.x.

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4

Hinedi, S. "NASA's next generation all-digital deep space network breadboard receiver." IEEE Transactions on Communications 41, no. 1 (1993): 246–57. http://dx.doi.org/10.1109/26.212383.

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Ge, Ying. "Characterizations of sn-metrizable spaces." Publications de l'Institut Math?matique (Belgrade) 74, no. 88 (2003): 121–28. http://dx.doi.org/10.2298/pim0374121g.

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We give some characterizations of sn-metrizable spaces. We prove that a space is an sn-metrizable space if and only if it has a locally-finite point-star sn-network. As an application of the result, a space is an sn-metrizable space if and only if it is a sequentially quotient, ? (compact), ?-image of a metric space.

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Tuyen, Luong. "Spaces with σ-locally finite Lindelöf sn-networks". Publications de l'Institut Math?matique (Belgrade) 93, № 107 (2013): 145–52. http://dx.doi.org/10.2298/pim1307145t.

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We prove that a space X has a ?-locally finite Lindel?f sn-network if and only if X is a compact-covering compact and mssc-image of a locally separable metric space, if and only if X is a sequentially-quotient ? and mssc-image of a locally separable metric space, where ?compact-covering? (or ?sequentially-quotient?) can not be replaced by ?sequence-covering?. As an application, we give a new characterization of spaces with locally countable weak bases.

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Senghore, Fatima, Enrique Campos-Nanez, Pavel Fomin, and James S. Wasek. "Using Social Network Analysis to Investigate the Potential of Innovation Networks: Lessons Learned from NASA's International Space Apps Challenge." Procedia Computer Science 28 (2014): 380–88. http://dx.doi.org/10.1016/j.procs.2014.03.047.

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Senghore, Fatima, Enrique Campos-Nanez, Pavel Fomin, and James S. Wasek. "Applying social network analysis to validate mass collaboration innovation drivers: An empirical study of NASA's International Space Apps Challenge." Journal of Engineering and Technology Management 37 (July 2015): 21–31. http://dx.doi.org/10.1016/j.jengtecman.2015.08.007.

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9

Sovers, O. J. "An Extragalactic Reference Frame From DSN VLBI Measurements–1989." Symposium - International Astronomical Union 141 (1990): 261–70. http://dx.doi.org/10.1017/s0074180900086915.

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Assessment of the impact of recent improvements in Deep Space Network (DSN) instrumentation, as well as of joint data analyses, provide a prognosis for the accuracy level to be expected in future realizations of an inertial radio reference frame. Intercontinental dual-frequency radio interferometric measurements during 68 sessions (including two recent sessions employing Mark III instrumentation) from 1978 to 1989 using NASA's DSN stations in California, Spain, and Australia give 8900 pairs of delay and delay rate observations. Analysis yields a catalog of positions of 200 extragalactic radio

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Sovers, O. J., and R. N. Treuhaft. "Radio Reference Frame Stability from VLBI Data." Symposium - International Astronomical Union 129 (1988): 331–32. http://dx.doi.org/10.1017/s0074180900134898.

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Intercontinental radio interferometric measurements between NASA's Deep Space Network stations yield a catalog of positions of 106 extragalactic radio sources, uniformly distributed between −45° and +85° declination. Almost all of the source positions have formal uncertainties between 0.5 and 3 milliarcseconds. Estimates of three independent sets of 32 source coordinates at average epochs 1980.0, 1983.2, and 1984.5 assess the level of stability of the reference frame over a five-year period. Comparisons of the three sets of source coordinates show a number of cases of > 2σ differences, part

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Schwickert, Christian, and Rainer Pöttgen. "SrCo2Sn8 and BaCo2Sn8: Tin-rich Stannides with Distorted SnSn6 Octahedra within Three-dimensional [Co2Sn8] Networks." Zeitschrift für Naturforschung B 68, no. 1 (2013): 17–22. http://dx.doi.org/10.5560/znb.2013-2293.

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The tin-rich stannides SrCo2Sn8 and BaCo2Sn8 were synthesized from the elements in sealed tantalum tubes. They crystallize with a new structure type, space group Cccm with a=1006.0(3), b=1514.4(6), c=1385.0(6) pm for SrCo2Sn8 and a=1032.8(2), b=1516.8(3), c=1405.1(3) pm for BaCo2Sn8. The structure of the barium compound was refined on the basis of single-crystal Xray diffractometer data: wR2=0.0450, 1715 F2 values, 57 variables. The cobalt atoms have seven nearest tin neighbors with Co-Sn distances ranging from 257 to 273 pm. These CoSn7 units are condensed via common rectangular faces to [Co2

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Sovers, O. J., C. D. Edwards, C. S. Jacobs, G. E. Lanyi, and R. N. Treuhaft. "The JPL 1986–3 Extragalactic Reference Frame." Symposium - International Astronomical Union 133 (1988): 461–64. http://dx.doi.org/10.1017/s0074180900140021.

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Intercontinental dual-frequency radio interferometric measurements were carried out during 1978 to 1985 between NASA's Deep Space Network stations in California, Spain, and Australia. Analysis of 6800 pairs of delay and delay rate observations made during 51 sessions produced a catalog of positions of 106 extragalactic radio sources, fairly uniformly distributed over the celestial sphere between −45° and +85° declination. Almost all of the resulting source positions have formal uncertainties between 0.5 and 3 milliarcseconds, with their distributions peaking somewhat below 1 mas. Root-mean-squ

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Tetlock, Erica, Brenda Toth, Aaron Berg, Tracy Rowlandson, and Jaison Thomas Ambadan. "An 11-year (2007–2017) soil moisture and precipitation dataset from the Kenaston Network in the Brightwater Creek basin, Saskatchewan, Canada." Earth System Science Data 11, no. 2 (2019): 787–96. http://dx.doi.org/10.5194/essd-11-787-2019.

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Abstract. Soil moisture and precipitation have been monitored in a hydrometeorological network situated within the Brightwater Creek basin, east of Kenaston, Saskatchewan, Canada, since 2007. The majority of the prairie landscape is annually cropped with some sections in pasture. This agricultural region is ideal for remote-sensing validation and calibration and, in conjunction with the flux tower situated within the network, hydrological model validation. Remote-sensing validation collaborations have included the European Space Agency's Soil Moisture and Ocean Salinity (SMOS) and NASA's Soil

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DEGNAN, JOHN J. "ASYNCHRONOUS LASER TRANSPONDERS: A NEW TOOL FOR IMPROVED FUNDAMENTAL PHYSICS EXPERIMENTS." International Journal of Modern Physics D 16, no. 12a (2007): 2137–50. http://dx.doi.org/10.1142/s0218271807011310.

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Since 1964, the NASA Goddard Space Flight Center (GSFC) has been using short pulse lasers to range to artificial satellites equipped with passive retroreflectors. Today, a global network of 40 satellite laser ranging (SLR) stations, under the auspices of the International Laser Ranging Service (ILRS), routinely tracks two dozen international space missions with few-millimeter precision using picosecond pulse lasers in support of Earth science. Lunar laser ranging (LLR) began in 1969, shortly after NASA's Apollo 11 mission placed the first of five retroreflector packages on the Moon. An importa

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Riecken, Jan F., Adel F. Al Alam, Bernard Chevalier, Samir F. Matar, and Rainer Pöttgen. "Structure and Chemical Bonding of PrRuSn." Zeitschrift für Naturforschung B 63, no. 9 (2008): 1062–68. http://dx.doi.org/10.1515/znb-2008-0908.

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The new ternary stannide PrRuSn was synthesized from the elements via arc-melting. PrRuSn is isopointal to the orthorhombic TiNiSi-type structure, space group Pnma. The structure was characterized by X-ray powder and single crystal diffraction: a = 761.7(2), b = 483.9(2) and c = 730.3(3) pm, wR2 = 0.0386, 433 F2 values, 20 variables. The ruthenium and tin atoms in PrRuSn build up a three-dimensional [RuSn] polyanionic network with Ru-Sn distances in the range 268 - 274 pm. The praseodymium atoms fill channels within the polyanion. They bind to the network via short Pr-Ru distances of 301 and 3

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David, Leslie, François-Marie Bréon, and Frédéric Chevallier. "XCO<sub>2</sub> estimates from the OCO-2 measurements using a neural network approach." Atmospheric Measurement Techniques 14, no. 1 (2021): 117–32. http://dx.doi.org/10.5194/amt-14-117-2021.

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Abstract. The Orbiting Carbon Observatory (OCO-2) instrument measures high-resolution spectra of the sun's radiance reflected at the earth's surface or scattered in the atmosphere. These spectra are used to estimate the column-averaged dry air mole fraction of CO2 (XCO2) and the surface pressure. The official retrieval algorithm (NASA's Atmospheric CO2 Observations from Space retrievals, ACOS) is a full-physics algorithm and has been extensively evaluated. Here we propose an alternative approach based on an artificial neural network (NN) technique. For training and evaluation, we use as refere

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Orlando, S., M. Ono, S. Nagataki, et al. "Hydrodynamic simulations unravel the progenitor-supernova-remnant connection in SN 1987A." Astronomy & Astrophysics 636 (April 2020): A22. http://dx.doi.org/10.1051/0004-6361/201936718.

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Context. Massive stars end their lives in catastrophic supernova (SN) explosions. Key information on the explosion processes and on the progenitor stars can be extracted from observations of supernova remnants (SNRs), which are the outcome of SNe. Deciphering these observations, however, is challenging because of the complex morphology of SNRs. Aims. We aim to link the dynamical and radiative properties of the remnant of SN 1987A to the geometrical and physical characteristics of the parent aspherical SN explosion and to the internal structure of its progenitor star. Methods. We performed comp

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Schwickert, Christian, Florian Winter, and Rainer Pöttgen. "The Stannides EuPd2Sn2, EuPt2Sn2, EuAu2Sn2, and Eu5.4Sn5.6 – Structure and Magnetic Properties." Zeitschrift für Naturforschung B 69, no. 7 (2014): 775–85. http://dx.doi.org/10.5560/znb.2014-4098.

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The europium stannides EuT2Sn2 (T = Pd, Pt, Au) and Eu3Ag5.4Sn5.6 were synthesized by highfrequency melting of the elements in sealed niobium ampoules in a water-cooled sample chamber. All samples were characterized by powder X-ray diffraction. The EuT2Sn2 (T = Pd, Pt, Au) stannides crystallize with the CaBe2Ge2-type structure, space group P4/nmm. The structure of EuPd2Sn2 was refined from single-crystal X-ray diffractometer data: a = 462.44(8), c = 1045.8(3) pm, wR = 0.0402, 237 F2 values and 15 refined variables. The palladium and tin atoms build up a threedimensional [Pd2Sn2] polyanionic ne

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Wendorff, Marco, and Caroline Röhr. "Neue gemischte Zinn-reiche Erdalkalimetall-Stannide – Synthese, Strukturchemie und chemische Bindung / New Mixed Tin-rich Alkaline Earth Stannides – Synthesis, Structural Chemistry and Chemical Bonding." Zeitschrift für Naturforschung B 66, no. 3 (2011): 245–61. http://dx.doi.org/10.1515/znb-2011-0306.

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Ternary mixed Ca/Ba-Sr pentastannides AIISn5 (AII = Ca, Sr, Ba) have been synthesized from stoichiometric mixtures of the elements or from tin-rich melts. The crystal structures of two new compounds of overall composition ASn5 (A = Sr, Ba) were determined by means of single-crystal X-ray data. The structures of both Sr0.94Ba0.06Sn5 (monoclinic, space group C2/m, a = 1762.8(11), b = 704.1(3), c = 1986(2) pm, β = 100.31(6)º, Z = 14, R1 = 0.0996) and Sr0.89Ba0.11Sn5 (orthorhombic, space group Cmcm, a = 708.1(2), b = 1770.4(8), c = 2781.6(11) pm, Z = 20 , R1 = 0.0821) are closely related and can b

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Buiat, Martina, Federico Porcù, and Stefano Dietrich. "Observing relationships between lightning and cloud profiles by means of a satellite-borne cloud radar." Atmospheric Measurement Techniques 10, no. 1 (2017): 221–30. http://dx.doi.org/10.5194/amt-10-221-2017.

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Abstract. Cloud electrification and related lightning activity in thunderstorms have their origin in the charge separation and resulting distribution of charged iced particles within the cloud. So far, the ice distribution within convective clouds has been investigated mainly by means of ground-based meteorological radars. In this paper we show how the products from Cloud Profiling Radar (CPR) on board CloudSat, a polar satellite of NASA's Earth System Science Pathfinder (ESSP), can be used to obtain information from space on the vertical distribution of ice particles and ice content and relat

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Cavazzani, S., S. Ortolani, A. Bertolo, et al. "Sky Quality Meter and satellite correlation for night cloud-cover analysis at astronomical sites." Monthly Notices of the Royal Astronomical Society 493, no. 2 (2020): 2463–71. http://dx.doi.org/10.1093/mnras/staa416.

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ABSTRACT The analysis of night cloud cover is very important for astronomical observations in real time, considering a typical observation time of about 15 minutes, and to provide statistics. In this article, we use the Sky Quality Meter (SQM) for high-resolution temporal analysis of the La Silla and Asiago (Ekar Observatory) sky: 3 and 5 minutes respectively. We investigate the annual temporal evolution of the natural contributions of the sky at a site not influenced by artificial light at night (ALAN) and at one highly influenced. We also make a correlation between GOES and Aqua satellite da

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Sarkar, Kartick C., Orly Gnat, and Amiel Sternberg. "Non-equilibrium ionization and radiative transport in an evolving supernova remnant." Monthly Notices of the Royal Astronomical Society 504, no. 1 (2021): 583–600. http://dx.doi.org/10.1093/mnras/stab582.

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ABSTRACT We present numerical simulations of the evolution of a supernova (SN) remnant expanding into a uniform background medium with density $n_\mathrm{ H} = 1.0\, \mbox{ cm}^{-3}$ and temperature of 104 K. We include a dynamically evolving non-equilibrium ionization (NEI) network (consisting of all the ions of H, He, C, N, O, Ne, Mg, Si, S, Fe), frequency dependent radiation transfer (RT), thermal conduction, and a simple dust evolution model, all intra-coupled to each other and to the hydrodynamics. We assume spherical symmetry. Photoionization, radiation losses, photo-heating, charge-exch

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Möller, A., and T. de Boissière. "SuperNNova: an open-source framework for Bayesian, neural network-based supernova classification." Monthly Notices of the Royal Astronomical Society 491, no. 3 (2019): 4277–93. http://dx.doi.org/10.1093/mnras/stz3312.

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ABSTRACT We introduce SuperNNova, an open-source supernova photometric classification framework that leverages recent advances in deep neural networks. Our core algorithm is a recurrent neural network (RNN) that is trained to classify light curves using only photometric information. Additional information such as host-galaxy redshift can be incorporated to improve performance. We evaluate our framework using realistic supernova simulations that include survey detection. We show that our method, for the type Ia versus non-Ia supernova classification problem, reaches accuracies greater than 96.9

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Grayling, M., C. P. Gutiérrez, M. Sullivan, et al. "Understanding the extreme luminosity of DES14X2fna." Monthly Notices of the Royal Astronomical Society 505, no. 3 (2021): 3950–67. http://dx.doi.org/10.1093/mnras/stab1478.

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ABSTRACT We present DES14X2fna, a high-luminosity, fast-declining Type IIb supernova (SN IIb) at redshift z = 0.0453, detected by the Dark Energy Survey (DES). DES14X2fna is an unusual member of its class, with a light curve showing a broad, luminous peak reaching Mr ≃ −19.3 mag 20 d after explosion. This object does not show a linear decline tail in the light curve until ≃60 d after explosion, after which it declines very rapidly (4.30 ± 0.10 mag 100 d−1 in the r band). By fitting semi-analytic models to the photometry of DES14X2fna, we find that its light curve cannot be explained by a stand

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Rufai, Kazeem Idowu. "Attack Detection in a Rule-Based System Using Fuzzy Spiking Neural P System." International Journal of Informatics and Communication Technology (IJ-ICT) 5, no. 1 (2016): 11. http://dx.doi.org/10.11591/ijict.v5i1.pp11-20.

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The virtual area of communication known as cyber space brought about by the debut of the internet has enabled some cyber crimes – ‘Intrusion’ inclusive. So, efforts are being geared towards ensuring that reliable and efficient Intrusion Detection Systems (IDSs) are developed to curtail this menace. However, Spiking Neural P (SN P) systems have been established as a class of distributed parallel computing models. So, in this paper, a novel network intrusion prediction model based on trapezoidal Fuzzy Reasoning Spiking Neural P (tFRSN P) system, is implemented for the very first time for the det

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Diallo, Waly, Libasse Diop, Cheikh Abdoul Khadir Diop, Hélène Cattey, and Laurent Plasseraud. "Synthesis, spectroscopic study, and crystal structure of a new organotin(IV) selenate derivative." Main Group Metal Chemistry 41, no. 5-6 (2018): 183–88. http://dx.doi.org/10.1515/mgmc-2018-0029.

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Abstract The polymeric organotin(IV) selenate complex [(Me3Sn)3(SeO4)(OH)]n (1) has been isolated as single crystals from the reaction of [(Me2NH2)2SeO4] and Me3SnCl in methanol. In the solid state, compound 1 was characterized by X-ray diffraction analysis, Fourier transform-infrared spectroscopy, and elemental analysis. 1 crystallizes in the orthorhombic system space group Pbca with a=11.0231(2) Å, b=16.3461(3) Å, c=20.9945(4) Å, α=β=γ=90°, V=3782.89(12) Å3, and Z=8. Its structure can be described as a polymeric zigzag chain based on Me3Sn moieties linked by tridentate selenate anions. Penda

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Beirle, S., N. Spichtinger, A. Stohl, et al. "Estimating the NO<sub>x</sub> produced by lightning from GOME and NLDN data: a case study in the Gulf of Mexico." Atmospheric Chemistry and Physics 6, no. 4 (2006): 1075–89. http://dx.doi.org/10.5194/acp-6-1075-2006.

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Abstract. Nitrogen oxides (NOxNO+NO2) play an important role in tropospheric chemistry, in particular in catalytic ozone production. Lightning provides a natural source of nitrogen oxides, dominating the production in the tropical upper troposphere, with strong impact on tropospheric ozone and the atmosphere's oxidizing capacity. Recent estimates of lightning produced NOx (LNOx) are of the order of 5 Tg [N] per year with still high uncertainties in the range of one order of magnitude. The Global Ozone Monitoring Experiment (GOME) on board the ESA-satellite ERS-2 allows the retrieval of troposp

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Beirle, S., N. Spichtinger, A. Stohl, et al. "Estimating the NO<sub>x</sub> produced by lightning from GOME and NLDN data: a case study in the Gulf of Mexico." Atmospheric Chemistry and Physics Discussions 5, no. 6 (2005): 11295–329. http://dx.doi.org/10.5194/acpd-5-11295-2005.

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Abstract. Nitrogen oxides (NOx=NO+NO2) play an important role in tropospheric chemistry, in particular in catalytic ozone production. Lightning provides a natural source of nitrogen oxides, dominating the production in the tropical upper troposphere, with strong impact on tropospheric ozone and the atmosphere's oxidizing capacity. Recent estimates of lightning produced NOx (LNOx) are of the order of 5 Tg [N] per year with still high uncertainties in the range of one order of magnitude. The Global Ozone Monitoring Experiment (GOME) on board the ESA-satellite ERS-2 allows the retrieval of tropos

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Komasi, Milad, Shohreh Fatemi, and Seyed Hesam Mousavi. "Kinetic Modelling of Propane Dehydrogenation over a Pt–Sn/hierarchical SAPO-34 Zeolite Catalyst, Including Catalyst Deactivation." Progress in Reaction Kinetics and Mechanism 42, no. 4 (2017): 344–60. http://dx.doi.org/10.3184/146867817x14954764850397.

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Pt–Sn/hierarchical SAPO-34 was synthesised and kinetically modelled as an efficient and selective catalyst for propylene production through propane dehydrogenation. The kinetics of the reaction network were studied in an integral fixed-bed reactor at three temperatures of 550, 600 and 650 °C and weight hourly space velocities of 4 and 8 h−1 with a feed containing hydrogen and propane with relative molar ratios of 0.2, 0.5 and 0.8, at normal pressure. The experiments were performed in accordance with the full factorial experimental design. The kinetic models were constructed on the basis of dif

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Toth, Viktor T., and Slava G. Turyshev. "The Pioneer anomaly: seeking an explanation in newly recovered data." Canadian Journal of Physics 84, no. 12 (2006): 1063–87. http://dx.doi.org/10.1139/p07-005.

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The Pioneer 10 and 11 spacecraft yielded very accurate navigation in deep space that was, however, limited by a small, anomalous frequency drift of their carrier signals received by the radio-tracking stations of the NASA Deep Space Network (DSN). This drift signifies a discrepancy between the frequency of the Doppler signals observed by the DSN and that frequency modeled using modern-day deep space navigational codes. This discrepancy, evident in the data for both spacecraft, was interpreted as an approximately constant acceleration. This acceleration has become known as the Pioneer anomaly.

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Zhou, Minqiang, Bart Dils, Pucai Wang, et al. "Validation of TANSO-FTS/GOSAT XCO<sub>2</sub> and XCH<sub>4</sub> glint mode retrievals using TCCON data from near-ocean sites." Atmospheric Measurement Techniques 9, no. 3 (2016): 1415–30. http://dx.doi.org/10.5194/amt-9-1415-2016.

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Abstract. The thermal And near infrared sensor for carbon observations Fourier transform spectrometer (TANSO-FTS) on board the Greenhouse Gases Observing Satellite (GOSAT) applies the normal nadir mode above the land (“land data”) and sun glint mode over the ocean (“ocean data”) to provide global distributions of column-averaged dry-air mole fractions of CO2 and CH4, or XCO2 and XCH4. Several algorithms have been developed to obtain highly accurate greenhouse gas concentrations from TANSO-FTS/GOSAT spectra. So far, all the retrieval algorithms have been validated with the measurements from gro

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Zhou, M., B. Dils, P. Wang, et al. "Validation of TANSO-FTS/GOSAT XCO<sub>2</sub> and XCH<sub>4</sub> glint mode retrievals using TCCON data from near-ocean sites." Atmospheric Measurement Techniques Discussions 8, no. 10 (2015): 10897–935. http://dx.doi.org/10.5194/amtd-8-10897-2015.

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Abstract. Thermal And Near infrared Sensor for carbon Observations Fourier Transform Spectrometer (TANSO-FTS) on board The Greenhouse gases Observing SATellite (GOSAT) applies the normal nadir mode above the land ("land data") and sun glint mode over the ocean ("ocean data") to provide global distributions of column-averaged dry-air mole fractions of CO2 and CH4, or XCO2 and XCH4. Several algorithms have been developed to obtain highly accurate greenhouse gas concentrations from TANSO-FTS/GOSAT spectra. So far, all the retrieval algorithms have been validated with the measurements from ground-

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Kim, Dae-Won, Doyeob Yeo, Coryn A. L. Bailer-Jones, and Giyoung Lee. "Deep transfer learning for the classification of variable sources." Astronomy & Astrophysics 653 (September 2021): A22. http://dx.doi.org/10.1051/0004-6361/202140369.

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Ongoing or upcoming surveys such as Gaia, ZTF, or LSST will observe the light curves of billions or more astronomical sources. This presents new challenges for identifying interesting and important types of variability. Collecting a sufficient amount of labeled data for training is difficult, especially in the early stages of a new survey. Here we develop a single-band light-curve classifier based on deep neural networks and use transfer learning to address the training data paucity problem by conveying knowledge from one data set to another. First we train a neural network on 16 variability f

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Tobin, Kenneth J., Roberto Torres, Wade T. Crow, and Marvin E. Bennett. "Multi-decadal analysis of root-zone soil moisture applying the exponential filter across CONUS." Hydrology and Earth System Sciences 21, no. 9 (2017): 4403–17. http://dx.doi.org/10.5194/hess-21-4403-2017.

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Abstract. This study applied the exponential filter to produce an estimate of root-zone soil moisture (RZSM). Four types of microwave-based, surface satellite soil moisture were used. The core remotely sensed data for this study came from NASA's long-lasting AMSR-E mission. Additionally, three other products were obtained from the European Space Agency Climate Change Initiative (CCI). These datasets were blended based on all available satellite observations (CCI-active, CCI-passive, and CCI-combined). All of these products were 0.25° and taken daily. We applied the filter to produce a soil moi

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Read, Pam, Chirag Shah, Lupita S-O’Brien, and Jaqueline Woolcott. "‘Story of one’s life and a tree of friends’ – understanding millennials’ information behaviour in social networks." Journal of Information Science 38, no. 5 (2012): 489–97. http://dx.doi.org/10.1177/0165551512453381.

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Exploring ways in which new technology impacts adolescents’ information behaviours and creates a social space requires holistic investigation. A qualitative study of 21 seniors in an upper-middle-class suburban high school revealed highly individualized use of Facebook and its features. These included: (i) Friends groups of 50—3700 members, with even the largest groups representative primarily of face-to-face connections, and (ii) a clear articulation within those groups of various categories, each with its own distinct communicative channel and style. A meaningful connection was found between

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Zenati, Yossef, Alexey Bobrick, and Hagai B. Perets. "Faint rapid red transients from neutron star–CO white dwarf mergers." Monthly Notices of the Royal Astronomical Society 493, no. 3 (2020): 3956–65. http://dx.doi.org/10.1093/mnras/staa507.

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ABSTRACT Mergers of neutron stars (NS) and white dwarfs (WD) may give rise to observable explosive transient events. We use 3D hydrodynamical (smoothed particle hydrodynamics – SPH) simulations and 2D hydrodynamical–thermonuclear simulations (using the flash adaptive mesh refinement code) to model the disruption of CO-WDs by NSs, which produce faint transient events. We post-process the simulations using a large nuclear network and make use of the SuperNu radiation transfer code to predict the observational signatures and detailed properties of these transients. We calculate the light curves a

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Wing, Robin, Sophie Godin-Beekmann, Wolfgang Steinbrecht, et al. "Evaluation of the new DWD ozone and temperature lidar during the Hohenpeißenberg Ozone Profiling Study (HOPS) and comparison of results with previous NDACC campaigns." Atmospheric Measurement Techniques 14, no. 5 (2021): 3773–94. http://dx.doi.org/10.5194/amt-14-3773-2021.

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Abstract. A newly upgraded German Weather Service (DWD) ozone and temperature lidar (HOH) located at the Hohenpeißenberg Meteorological Observatory (47.8∘ N, 11.0∘ E) has been evaluated through comparison with the travelling standard lidar operated by NASA's Goddard Space Flight Center (NASA GSFC Stratospheric Ozone (STROZ) lidar), satellite overpasses from the Microwave Limb Sounder (MLS), the Sounding of the Atmosphere using Broadband Emission Radiometry (SABER), the Ozone Mapping and Profiler Suite (OMPS), meteorological radiosondes launched from Munich (65 km northeast), and locally launch

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GEHRELS, NEIL. "SWIFT OBSERVATIONS OF GAMMA-RAY BURSTS." International Journal of Modern Physics D 17, no. 09 (2008): 1311–17. http://dx.doi.org/10.1142/s0218271808012863.

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The Swift mission, launched on 20 November 2004, is detecting ~ 100 gamma-ray bursts (GRBs) each year, and immediately (within ~ 90 s) starting X-ray and UV/optical observations of the afterglow. It has already collected an impressive database including prompt emission to higher sensitivities than BATSE, uniform monitoring of afterglows, and rapid follow-up by other observatories notified through the Gamma-ray bursts Coordinates Network (GCN). The X-ray afterglows have been found to have complex temporal shapes including tails emission from the prompt phase and bright flares. X-ray and optical

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Meza, Nicolás, J. L. Prieto, A. Clocchiatti, et al. "The extraplanar type II supernova ASASSN-14jb in the nearby edge-on galaxy ESO 467-G051." Astronomy & Astrophysics 629 (September 2019): A57. http://dx.doi.org/10.1051/0004-6361/201834972.

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We present optical photometry and spectroscopy of the Type II supernova ASASSN-14jb, together with Very Large Telescope (VLT) Multi Unit Spectroscopic Explorer (MUSE) integral field observations of its host galaxy and a nebular-phase spectrum. This supernova, in the nearby galaxy ESO 467-G051 (z = 0.006), was discovered and followed-up by the all-sky automated survey for supernovae (ASAS-SN). We obtained well-sampled las cumbres network (LCOGTN) BVgri and Swift w2m1w1ubv optical, near-UV/optical light curves, and several optical spectra in the early photospheric phases. The transient ASASSN-14

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Sekar, Kanagaraj, Amarendra Kumar, Xiaohong Liu, Ming-Daw Tsai, Michael H. Gelb, and Muttaiya Sundaralingam. "Structure of the Complex of Bovine Pancreatic Phospholipase A2 with a Transition-State Analogue." Acta Crystallographica Section D Biological Crystallography 54, no. 3 (1998): 334–41. http://dx.doi.org/10.1107/s090744499701247x.

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The 1.89 Å resolution structure of the complex of bovine pancreatic phospholipase A2 (PLA2) with the transition-state analogue L-1-O-octyl-2-heptylphosphonyl-sn-glycero-3-phosphoethanolamine (TSA) has been determined. The crystal of the complex is trigonal, space group P3121, a = b = 46.58 and c = 102.91 Å and isomorphous to the native recombinant wild type (WT). The structure was refined to a final crystallographic R value of 18.0% including 957 protein atoms, 88 water molecules, one calcium ion and all 31 non-H atoms of the inhibitor at 1.89 Å resolution. In all, 7 726 reflections [F\gt2\sig

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Niepmann, Dirk, Rainer Pöttgen, Kristin M. Poduska, Francis J. DiSalvo, Henning Trill, and Bernd D. Mosel. "Structure and Properties of the Stannides CeAuSn, Ce3Rh4Sn13, and Ce3Ir4Sn13." Zeitschrift für Naturforschung B 56, no. 1 (2001): 1–8. http://dx.doi.org/10.1515/znb-2001-0102.

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Abstract CeAuSn, Ce3Rh4Sn13, and Ce3lr4Sn13 were prepared by reaction of the elements in an arc-melting furnace and subsequent annealing at 970 K for two weeks. The three stannides were investigated by X-ray powder and single crystal techniques. CeAuSn crystallizes with the NdPtSb type, space group P63mc: a = 472.7(2), c = 771.6(3) pm, wR2 = 0.0230,208 F2 values, 11 variable parameters, and BASF = 0.40(2). The gold and tin atoms form a pronounced two-dimensional [AuSn] polyanion which consists of slightly puckered Au3Sn3 hexagons. ,19Sn Mössbauer data at 78 K show one signal at an isomer shift

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Steinbrecht, W., T. J. McGee, L. W. Twigg, et al. "Intercomparison of stratospheric ozone and temperature profiles during the October 2005 Hohenpeissenberg Ozone Profiling Experiment (HOPE)." Atmospheric Measurement Techniques Discussions 2, no. 1 (2009): 37–86. http://dx.doi.org/10.5194/amtd-2-37-2009.

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Abstract. Thirteen clear nights in October 2005 allowed successful intercomparison of the stationary lidar operated since 1987 by the German Weather Service (DWD) at Hohenpeissenberg (47.8° N, 11.0° E) with the Network for the Detection of Atmospheric Composition Change (NDACC) travelling standard lidar operated by NASA's Goddard Space Flight Center. Both lidars provide ozone profiles in the stratosphere, and temperature profiles in the strato- and mesosphere. Additional ozone profiles came from on-site Brewer/Mast ozonesondes, additional temperature profiles from Vaisala RS92 radiosondes laun

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de Leeuw, Gerrit, Larisa Sogacheva, Edith Rodriguez, et al. "Two decades of satellite observations of AOD over mainland China using ATSR-2, AATSR and MODIS/Terra: data set evaluation and large-scale patterns." Atmospheric Chemistry and Physics 18, no. 3 (2018): 1573–92. http://dx.doi.org/10.5194/acp-18-1573-2018.

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Abstract. The retrieval of aerosol properties from satellite observations provides their spatial distribution over a wide area in cloud-free conditions. As such, they complement ground-based measurements by providing information over sparsely instrumented areas, albeit that significant differences may exist in both the type of information obtained and the temporal information from satellite and ground-based observations. In this paper, information from different types of satellite-based instruments is used to provide a 3-D climatology of aerosol properties over mainland China, i.e., vertical p

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Keppens, Arno, Jean-Christopher Lambert, José Granville, et al. "Quality assessment of the Ozone_cci Climate Research Data Package (release 2017) – Part 2: Ground-based validation of nadir ozone profile data products." Atmospheric Measurement Techniques 11, no. 6 (2018): 3769–800. http://dx.doi.org/10.5194/amt-11-3769-2018.

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Abstract. Atmospheric ozone plays a key role in air quality and the radiation budget of the Earth, both directly and through its chemical influence on other trace gases. Assessments of the atmospheric ozone distribution and associated climate change therefore demand accurate vertically resolved ozone observations with both stratospheric and tropospheric sensitivity, on both global and regional scales, and both in the long term and at shorter timescales. Such observations have been acquired by two series of European nadir-viewing ozone profilers, namely the scattered-light UV–visible spectromet

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Steinbrecht, W., T. J. McGee, L. W. Twigg, et al. "Intercomparison of stratospheric ozone and temperature profiles during the October 2005 Hohenpeißenberg Ozone Profiling Experiment (HOPE)." Atmospheric Measurement Techniques 2, no. 1 (2009): 125–45. http://dx.doi.org/10.5194/amt-2-125-2009.

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Abstract. Thirteen clear nights in October 2005 allowed successful intercomparison of the lidar operated since 1987 by the German Weather Service (DWD) at Hohenpeißenberg (47.8° N, 11.0° E) with the Network for the Detection of Atmospheric Composition Change (NDACC) travelling standard lidar operated by NASA's Goddard Space Flight Center. Both lidars provide ozone profiles in the stratosphere, and temperature profiles in the strato- and mesosphere. Additional ozone profiles came from on-site Brewer/Mast ozonesondes, additional temperature profiles from Vaisala RS92 radiosondes launched at Muni

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46

Eugster, Hans P. "Granites and hydrothermal ore deposits: a geochemical framework." Mineralogical Magazine 49, no. 350 (1985): 7–23. http://dx.doi.org/10.1180/minmag.1985.049.350.02.

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AbstractThe geochemical evolution of tin-tungsten deposits and their associated sulphides can be discussed in terms of four sequential processes: acquisition of the ore-forming elements (OFEs) by the granitic magma, emplacement of these elements in minerals and residual melt of the crystallizing granite, release of the OFEs to the circulating hydrothermal fluids and transport to the depositional sites, and finally, deposition of ore minerals through interaction of these fluids with the wall rock. Based on their crystallographic behaviour, it is useful to distinguish three principal classes of

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Takahashi, Ichiro, Nao Suzuki, Naoki Yasuda, et al. "Photometric classification of Hyper Suprime-Cam transients using machine learning." Publications of the Astronomical Society of Japan 72, no. 5 (2020). http://dx.doi.org/10.1093/pasj/psaa082.

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Abstract The advancement of technology has resulted in a rapid increase in supernova (SN) discoveries. The Subaru/Hyper Suprime-Cam (HSC) transient survey, conducted from fall 2016 through spring 2017, yielded 1824 SN candidates. This gave rise to the need for fast type classification for spectroscopic follow-up and prompted us to develop a machine learning algorithm using a deep neural network with highway layers. This algorithm is trained by actual observed cadence and filter combinations such that we can directly input the observed data array without any interpretation. We tested our model

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Lin, JingLing, Fucai Lin, and Chuan Liu. "Hyperspace of finite unions of convergent sequences." Studia Scientiarum Mathematicarum Hungarica, September 3, 2021. http://dx.doi.org/10.1556/012.2021.01510.

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The symbol S(X) denotes the hyperspace of finite unions of convergent sequences in a Hausdor˛ space X. This hyper-space is endowed with the Vietoris topology. First of all, we give a characterization of convergent sequence in S(X). Then we consider some cardinal invariants on S(X), and compare the character, the pseudocharacter, the sn-character, the so-character, the network weight and cs-network weight of S(X) with the corresponding cardinal function of X. Moreover, we consider rank k-diagonal on S(X), and give a space X with a rank 2-diagonal such that S(X) does not Gδ -diagonal. Further, w

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Bietenholz, Michael F., Norbert Bartel, Atish Kamble, Raffaella Margutti, David Jacob Matthews, and Danny Milisavljevic. "SN 2014C: VLBI image shows a shell structure and decelerated expansion." Monthly Notices of the Royal Astronomical Society, January 4, 2021. http://dx.doi.org/10.1093/mnras/staa4003.

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Abstract We report on new Very Long Baseline Interferometry radio measurements of supernova 2014C in the spiral galaxy NGC 7331, made with the European VLBI Network ∼5 yr after the explosion, as well as on flux density measurements made with the Jansky Very Large Array (VLA). SN 2014C was an unusual supernova, initially of Type Ib, but over the course of ∼1 yr it developed strong Hα lines, implying the onset of strong interaction with some H-rich circumstellar medium (CSM). The expanding shock-front interacted with a dense shell of circumstellar material during the first year, but has now emer

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Khan, Zaheer Ullah, and Dechang Pi. "DeepSSPred: A Deep Learning Based Sulfenylation site predictor via a novel n-segmented optimize federated feature encoder." Protein & Peptide Letters 27 (December 2, 2020). http://dx.doi.org/10.2174/0929866527666201202103411.

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Background: S-sulfenylation (S-sulphenylation, or sulfenic acid) proteins, are special kinds of post-translation modification, which plays an important role in various physiological and pathological processes such as cytokine signaling, transcriptional regulation, and apoptosis. Despite these aforementioned significances, and by complementing existing wet methods, several computational models have been developed for sulfenylation cysteine sites prediction. However, the performance of these models was not satisfactory due to inefficient feature schemes, severe imbalance issues, and lack of an i

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