1,721,017 research outputs found
Wavelet Decomposition Of Submillimeter Solar Radio Bursts
No full textWe present the results of wavelet decomposition of fast-time structures during four solar flares observed by the Solar Submillimeter-wave Telescope at 212 GHz. The result of the analysis shows (1) observational evidence on the existence of submm-emission time variations in the range from a few tens of millisecond up to few seconds during solar flares, and (2) that when a solar flare is in progress the time scales reduce as the bulk of the emission flux time variations is increasing.21801/02/15211220Aschwanden, M.J., Kliem, B., Schwarz, U., Kurths, J., Dennis, B.R., Schwartz, R.A., (1998) Astrophys. J., 505, p. 941Bendjoya, Ph., Petit, J.-M., Spahn, F., (1993) ICARUS, 105, p. 385Correia, E., Kaufmann, P., (1987) Solar Phys., 111, p. 143Giménez De Castro, C.G., Raulin, J.-P., Makhmutov, V.S., Kaufmann, P., Costa, J.E.R., (1999) Astron. Astrophys. Suppl., 140, p. 373Giménez De Castro, C.G., Raulin, J.-P., Mandrini, C.H., Kaufmann, P., Magun, A., (2001) Astron. Astrophys., 366, p. 317Kaufmann, P., (2002) Solar Observations at Submillimeter Wavelengths, Lecture Notes in Physics Series, , Springer-Verlag, BerlinKaufmann, P., Strauss, F.M., Opher, R., Laporte, C., (1980) Astron. Astrophys., 87, p. 58Kaufmann, P., Correia, E., Costa, J.E.R., Zodi Vaz, A.M., Dennis, B.R., (1985) Nature, 313, p. 380Kaufmann, P., Trottet, G., Giménez De Castro, C.G., Costa, J.E.R., Raulin, J.-P., Schwartz, R.A., Magun, A., (2000) Solar Phys., 197, p. 361Kaufmann, P., Costa, J.E.R., Giménez De Castro, C.G., Hadako, Y.S., Kingsley, J.S., Kingsley, R.K., Levato, H., Silva, A.V.R., (2001) Proc.SBMO/IEEE MTT - S International Microwave and Optoelectronics Conference, , August 6-10, 2001, Belém, Para, BrazilTelecomunicasōes, 4, p. 18. , reprintedKaufmann, P., Raulin, J.-P., Correia, E., Costa, J.E.R., Giménez De Castro, C.G., Silva, A.V.R., Levato, H., Bauer, O.H., (2001) Astrophys. J., 548, pp. L95Kaufmann, P., Raulin, J.-P., Melo, A.M., Correia, E., Costa, J.E.R., Giménez De Castro, C.G., Silva, A.V.R., Rovira, M., (2002) Astrophys. J., 574, p. 1059Kiplinger, A.L., Dennis, B.R., Emslie, A.G., Frost, K.J., Orwig, L.E., (1983) Astrophys. J., 265, pp. L99Krüger, A., Kliem, B., Hildebrandt, J., Zaitsev, V.V., (1994) Astrophys. J. Suppl. Ser., 90, p. 683Kurths, J., Schwarz, U., (1994) Space Sci. Rev., 68, p. 171Machado, M.E., Oug, K.K., Emslie, A.G., Fishman, G.J., Meegan, C., Wilson, R., Paciesas, W.S., (1993) Adv. Space Res., 13, p. 175Makhmutov, V.S., Costa, J.E.R., Raulin, J.-P., Kaufmann, P., Lagrotta, P.R., Giménez De Castro, C.G., Magun, A., Arzner, K., (1998) Solar Phys., 178, p. 393Mallat, S.G., (1989) IEEE Transactions on Pattern Analysis and Machine Intelligence, 11, p. 674Pritchett, P.L., Wu, C.C., (1979) Phys. Fluids, 22, p. 2140Raulin, J.-P., Kaufmann, P., Olivieri, R., Correia, E., Makhmutov, V.S., Magun, A., (1998) Astrophys. J., 498, pp. L173Raulin, J.-P., Kaufmann, P., Giménez De Castro, C.G., Pacini, A.A., Makhmutov, V.S., Levato, H., Rovira, M., (2003) Astrophys. J., 592, p. 580Raulin, J.-P., Makhmutov, V.S., Kaufmann, P., Luethi, T., Hudson, H.S., Gary, D.E., Yoshimori, M., (2003) Astrophys. J., , in preparationScargle, J.D., Steiman-Cameron, T., Joung, K., Donoho, D.L., Crutchfield, J.P., Imamura, J., (1993) Astrophys. J., 411, pp. L91Schwarz, U., Kurths, J., Kliem, B., Krüger, A., Urpo, S.N., (1998) Astron. Astrophys. Suppl. Ser., 127, p. 309Tajima, T., Sakai, J., Nakajima, T., Kosugi, T., Brunel, F., Kundu, M.R., (1987) Astrophys. J., 321, p. 1031Takakura, T., Kaufmann, P., Costa, J.E.R., Degaonkar, S.S., Ohki, K., Nitta, N., (1983) Nature, 302, p. 317Vilmer, N., Trottet, G., Barat, C., Dezalay, J.P., Talon, R., Sunyaev, R., Terekhov, O., Kuznetsov, A., (1994) Space Sci. Rev., 68, p. 23
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Recent Results On Solar Activity At Submillimeter Wavelengths
No full textSince the installation of the Solar Submillimeter Telescope (SST) in 1999 in the Complejo Astronómico El Leoncito (CASLEO, Argentina), the almost unexplored solar emissions at frequencies >100 GHz started to reveal new insights about thermal and non-thermal processes in active regions. SST operates at the frequencies of 212 and 405 GHz providing the unique opportunity to distinguish and investigate emission mechanisms. We present a review of the most relevant findings obtained. An statistical study made with observations of a selected sample of active regions shows that their flux density spectra increase with frequency. Rapid brightenings (pulses) are always observed both at 212 and 405 GHz in association to solar flares lasting for some tens to hundreds of milliseconds. They are well correlated between the two frequencies and have flux spectra either flat or increasing with frequency. The flux of submillimeter wave pulses remain within the same order of magnitude for different bursts, ranging typically 100-300 s.f.u. at 212 GHz and 500-1000 s.f.u. at 405 GHz. The time evolution of the pulse occurrence rate usually reproduces the time profile of the X-rays/γ-rays emission, and the bulk emission at submillimeter waves, when the latter is observable. There are examples of good correlation between individual pulses at submillimeter waves and hard X-rays/γ-rays. Submillimeter pulses are not restricted to flare events, but appear to be a general phenomenon that occurs over active regions as well. The starting time of the rapid submillimeter wave pulses is coincident or precedes the projected launch time of the coronal mass ejections. SST observations of the November 4, 2003 large flare revealed a new and yet unknown spectral component with intensities increasing towards even higher frequencies, appearing along with, but separated from the well-known microwave component. © 2005 COSPAR. Published by Elsevier Ltd. All rights reserved.351017691773Bagalá, L.G., Bauer, O.H., Fernández Borda, R., Francile, C., Haerendel, G., Rieger, R., Rovira, M.G., The new Hα solar telescope at the German-Argentinian solar observatory (1999) Magnetic Fields and Solar Processes, pp. 959-964. , ESA, SP-448 (December)Bastian, T.S., Ewell, M.W., Zirin, H., The center-to-limb brightness variation of the Sun at lambda = 850 microns (1993) ApJ, 415, pp. 364-375Bendjoya, P., Petit, J.-M., Spahn, F., Wavelet analysis of the Voyager data on planetary rings. i - Description of the method (1993) Icarus, 105, pp. 385-399Castelli, J.P., Clemens, J., Radio spectrum of ail active solar region determined from the 20 July 1963 eclipse (1966) AJ, 71, pp. 652-656Clark, C.D., Park, W.M., (1968) Nature, 219, p. 922Coates, R., Measurements of solar radiation and atmospheric attenuation at 4.3-millimeters wavelength (1958) Proc. 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Phys., 4, pp. 58-66Kaufmann, P., Submillimeter/IR solar bursts from high energy electrons (1996) High Energy Solar Physics Workshop, pp. 379-393. , GSFC/NASAKaufmann, P., Correia, E., Costa, J.E.R., Zodi Vaz, A.M., A synchrotron/inverse Compton interpretation of a solar burst producing fast pulses at lambda less than 3-mm and hard X-rays (1986) A&A, 157, pp. 11-18Kaufmann, P., Costa, J.E.R., Giménez De Castro, C.G., Hadano, R., Kingsley, J.S., Kingsley, R.K., Levato, H., Silva, A.V.R., The new submillimeter-wave solar telescope (2001) Proceedings of the SBMO/IEEE MTT-S International Microwave and Optoelectronics Conference, pp. 439-441Kaufmann, P., Raulin, J.-P., Correia, E., Costa, J.E.R., De Castro, C.G.G., Silva, A.V.R., Levato, H., Bauer, O.H., Rapid submillimeter brightenings associated with a large solar flare (2001) ApJ, 548, pp. L95-L98Kaufmann, P., Raulin, J.P., Melo, A.M., Correia, E., Costa, J.E.R., De Castro, C.G.G., Silva, A.V.R., Rovira, M., Solar submillimeter and gamma-ray burst emission (2002) ApJ, 574, pp. 1059-1065Kaufmann, P., Giménez De Castro, C.G., Makhmutov, V.S., Raulin, J.P., Schwenn, R., Levato, H., Rovira, H., Launch of solar coronal mass ejections and submillimeter pulse bursts (2003) J. 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Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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