Mechanism of generation of the emission bands in the dynamic spectrum of the Crab pulsar     

Houshang Ardavan  ArzhangArdavan  John Singleton  Mario R. Perez 《Monthly notices of the Royal Astronomical Society》2008,388(2):873-883

We show that the proportionately spaced emission bands in the dynamic spectrum of the Crab pulsar fit the oscillations of the square of a Bessel function whose argument exceeds its order. This function has already been encountered in the analysis of the emission from a polarization current with a superluminal distribution pattern: a current whose distribution pattern rotates (with an angular frequency ω) and oscillates (with a frequency  Ω > ω  differing from an integral multiple of ω) at the same time. Using the results of our earlier analysis, we find that the dependence on frequency of the spacing and width of the observed emission bands can be quantitatively accounted for by an appropriate choice of the value of the single free parameter  Ω/ω  . In addition, the value of this parameter, thus implied by Hankins & Eilek's data, places the last peak in the amplitude of the oscillating Bessel function in question at a frequency  (∼Ω³/ω²)  that agrees with the position of the observed ultraviolet peak in the spectrum of the Crab pulsar. We also show how the suppression of the emission bands by the interference of the contributions from differing polarizations can account for the differences in the time and frequency signatures of the interpulse and the main pulse in the Crab pulsar. Finally, we put the emission bands in the context of the observed continuum spectrum of the Crab pulsar by fitting this broad-band spectrum (over 16 orders of magnitude of frequency) with that generated by an electric current with a superluminally rotating distribution pattern.  相似文献   

A digital earth platform for sustainability   总被引：1，自引：1，他引：0  

Mario Hernandez 《International Journal of Digital Earth》2017,10(4):342-355

ABSTRACT

Based on the experience of the International Society for Digital Earth (ISDE), this paper describes some challenges foreseen in order to develop a Digital Earth platform that can support the implementation of the Sustainable Development Goals. The use of ready-to-use derived geospatial information is essential. Future Earth’s methodology of ‘co-design’ aims to bring together natural, social scientists and decision makers to plan and carry out research for sustainability. Sustainability implies transdisciplinary research, but in order for scientists of different disciplines to work together, they will need to be able to share, access and use common data. This is by far not simple! While the good will to share data might exist, the associated technological, ethical and privacy issues are difficult to solve. An adequate e-infrastructure will be required. ISDE could consider to use the SDGs is the basis to develop the desired Digital Earth platform. This paper, by no means, covers everything for a Digital Earth platform, it aims to trigger research discussions and to have a good view about a starting point.  相似文献   

Sur les perturbations magnétiques à Mogadiscio     

Mario Bossolasco 《Pure and Applied Geophysics》1951,20(1):46-49

Summary The comparison of the geomagneticK-indices for Mogadiscio with the correspondingK _p for the whole earth, during the 2.nd Intern. Polar Year 1932–33, allows to deduce some features of the equatorial geomagnetic activity. Furthermore, evidence is adduced indicating that the geomagnetic disturbance at Mogadiscio is normal inH andD, while it appears slightly abnormal inZ.

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Communication presentée à l'Association Internationale de Magnétisme et Electricité Terrestres, IXe Assemblée Générale de l'UGGI, Bruxelles, Séance du 28 Août 1951.  相似文献   

Variazioni del moto polare della Terra e loro correlazioni meteorologiche     

Mario Bossolasco 《Pure and Applied Geophysics》1949,14(3-4):197-202

Riassunto Vengono documentate ed illustrate alcune correlazioni fra le alterazioni del moto di rotazione terrestre iniziatesi nel 1923 con gli eventi meteorologici; in particolare si discutono e si spiegano in tal modo le forti anomalie della pressione osservate a Genova nel periodo 1924–32.

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Zusammenfassung Störungen in der Bewegung des Erdkörpers und Verschiebungen seiner Rotaktionsachse rufen Wirkungen hervor, welcke mit der Anpassung der Luftmassen an den neuen Bewegungen und an den neuen Lagen der Rotaktionsachse sich ausdrucken. Das führt zu Veränderungen der Luftströmungen, der Luftdruckverteilungen und daher der Grossewetterlagen. Einige meteorologischen Korrelationen dieser Art werden für die bedeutende Störung der Polarbewegung des 1923 gezeigt. Nachher werden damit besonders die starken Luftdruckanomalien erklärt, welche in Genua in der Periode 1924–32 beobachtet worden sind.

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Sulle correnti telluriche nelle regioni equatoriali     

Mario Bossolasco 《Pure and Applied Geophysics》1947,10(1-2):41-53

Riassunto Si espongono i risultati delle osservazioni sulle correnti telluriche eseguite a Mogadiscio nel 1933 con misure delle due componenti NS ed EW, traendone alcune deduzioni che permettono di precisarne le caratteristiche, specie nei confronti del relativo andamento diurno.

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Summary The paper deals with the results of the earth-current-observations made at Mogadiscio during 1933. The analysis reveal elements for a new picture of the distribution of the earth-currents in the equatorial regions, particularly concerning the daily variation.

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Zusammenfassung Die Ergebnisse des Erdstrom-Beobachtungen durchgeführt in einigen Monaten des Jahres 1933 in Modagiscio sind angegeben. Aus des Diskussion folgen einige Elemente die eine Neubearbeitung des Darstellung des Erdstrom-Verteilung in dem äquatorialem Gürtel nötig machen und dazu dienen werden sollen. besonders in Beziehung auf den täglichen Gang.

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Sullo spostamento dei cicloni nel Mediterraneo     

Mario Bossolasco 《Pure and Applied Geophysics》1952,22(3-4):255-261

Riassunto Vengono esaminati due esempi di spostamento retrogrado di depressioni nel Mediterraneo, illustrandone le cause. Per uno di essi si calcolano gli elementi energetici, dimostrando come il rapportoK/P fra l'energia cinetica e quella potenziale della depressione costituisca un indice della sua capacità di proseguire il moto lungo la rotta precedente.

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Summary Two examples of retrograde displacement of depressions in the Mediterranean are being examined, explaining their causes. For one of them the energetic elements are calculated showing how the ratioK/P between the kinetic and the potential energy of the depression constitutes an index of its capacity to continue the motion along the preceding course.

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Zusammenfassung Es werden zwei Fälle rückläufiger Bewegungen, von Mittelmeerdepressionen untersucht und die Ursachen derselben erläutert. Für einen dieser Fälle werden die Grössen der Energie berechnet: und es wird gezeigt, dass das VerhältnisK/P zwischen kinetischer und potentieller Energie massgebend ist für die Fähigkeit der Depression, ihre Bewegung in der ursprünglichen Richtung fortzusetzen.

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Suscettivita' magnetica di alcuni minerali di magnetite     

Mario Bossolasco 《Pure and Applied Geophysics》1948,12(1-2):53-60

Riassunto Vengono esposti e discussi i risultati di alcune misure della suscetività magnetica di minerali magnetitiferi italiani. Fra l'altro si dimostra l'impossibilità di una legge generale di interdipendenza fra i valori della suscettività ed il carattere genetico dei giacimenti, indicando nuovi orientamenti per approfondire con successo simili indagini.

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Summary The results of some measures of magnetic susceptibility of italian magnetic ores are reported and discussed. It is proved the impossibility of a general relation between the magnitude of the susceptibility and the genetic character of the ores; however, new views are pointed out to successfully deepen the results.

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Zusammenfassung Die Ergebnisse einiger Suszeptibilit?ts-Messungen von ital. Magnetit-Mineralien verschiedener Genesis werden angegeben und erl?utert. U. a. beweist man, dass ein allgemeine Gesetz für eine einfache Zusammenhang zwischen den Werte der Suszeptibilit?t und die genetischen Eigentümlichkeiten der Lagerst?tten nicht bestehen kann. Neue Forschungsrichtungen dafür werden vorgeschlagen.

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Sulla distribuzione delle precipitazioni a Milano e nella regione circostante     

Mario Bossolasco 《Pure and Applied Geophysics》1948,11(1):132-141

Riassunto Richiamate le condizioni pluviometriche medie cui è soggetta la regione milanese, vengono illustrati e discussi i risultati ottenuti nel biennio 1946–1947 per la distribuzione della pioggia nell'area cittadina, durante la primavera, l'estate e l'autunno. L'influenza alteratrice delle città in tale distribuzione appare evidente, particolarmente nella primavera.

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Zusammenfassung Ausgehend von den mittleren Niederschlagsverhältnissen in der Region von Mailand, wird die Verteilung der Niederschläge im Frühjahr, Sommer und Herbst der Jahre 1946 und 1947 im Stadtareal von Mailand dargestellt und diskutiert. Der Einfluss der Stadt auf die Niederschlagsverteilung tritt deutlich in Erscheinung, besonders im Frühjahre.

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Le precipitazioni nevose nell'Italia Settentrionale: II     

Mario Bossolasco 《Pure and Applied Geophysics》1948,13(5-6):213-233

La Nota I venne pubblicata a pag. 286 e seg. del Vol. XII (Fasc. 5–6), 1948, di questa Rivista. Le numerazioni delle citazioni bibliografiche e delle formole fanno seguito a quelle usate nella Nota I.  相似文献   

Ottant'anni di Osservazioni Meteorologiche a Moncalieri (Torino)     

Prof. Dr. Sac. Dionigi Boddaert  Mario Bossolasco 《Pure and Applied Geophysics》1948,11(1):68-77

Riassunto Si espongono ed illustrano i valori medi dei principali elementi meteorologici osservati a Moncalieri senza alcuna interruzione nell'ottantennio 1865–1945 e durante il quarantennio 1907–1946 per il vento. L'analisi delle medie quinquennali ed annuali pone in luce qualche caratteristica della variazione secolare dei medesimi fattori.

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Zusammenfassung Die Mittelwerte der wichtigsten meteorologischen Elemente die in Moncalieri ohne Unterbrechung gesammelt worden sind, werden angegeben und zwar für den Zeitraum 1865–1945, ausgenommen für den Wind, deren Beobachtungen auf die Periode 1907–1946 sich beziehen. Die Gänge der fünfjährigen und jährlichen Mitteln zeigen einige Eigentümlichkeiten der sekularen Variation für denselben Elemente, die herausgehoben werden.

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