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981.
982.
Summary A diagram is being designed showing the six times and four times values of the probable error of the correlation coefficients in function of the number of correlated pairs of values forn=10 ton=400. Thereby it is possible to estimate the significance of the correlation coefficients without further calculations.
Zusammenfassung Es wird ein Diagramm entwickelt, das die sechs- bzw. vierfachen Werte der wahrscheinlichen Fehler der Korrelationskoeffizienten in Abhängigkeit von der Zahl der korrelierten Wertepaare fürn=10 bisn=400 zeigt und damit die Beurteilung der Signifikanz der Korrelationskoeffizienten in einfacher Weise ermöglicht.

Résumé Etablissement d'un diagramme indiquant les montants resp. sextuples et quadruples des erreurs probables des coefficients de corrélation en fonction du nombre de paires de valeurs considérées, pourn=10 jusqu' àn=400. Ce diagramme permet donc d'estimer aisément dans quelle mesure un coefficient de corrélation est significatif.


With 1 Figure  相似文献   
983.
This paper considers results from isotope-geochronological (K-Ar) studies of the products of Neogene-Quaternary volcanism in the Karacada? area, which is situated within the northern frontal part of the Arabian plate. It was found that magmatic activity has been evolving at this location for at least the last 11–10 Myr and was distinctly discrete in character. Three stages of volcanism have been identified: (I) Early or Miocene, ~11–6.7 Ma; (II) Middle or Pliocene-Early Quaternary, 4–1 Ma; and (III) Late or Late Quaternary, 0.4–0.1 Ma. The most recent manifestations of magmatic activity in the region date back to about 100000 years ago. An analysis of the spatial distribution of volcanic centers of different ages in the Karacada? neovolcanic area shows that the magmatism of that region involved a lateral migration of activity from northwest to southeast along a major regional tectonic fault. The migration was caused by the movement of local tension zones where the lithosphere was thinner and deep-seated mantle magmas were ascending.  相似文献   
984.
Zusammenfassung Durch die Deutsche Atlantische Expedition auf «Meteor» 1925–27 und das maritim-aerologische Werk der Deutschen Seewarte wurden zahlreiche Höhenwindmessungen auf dem Atlantischen Ozean gewonnen. Die Bearbeitung dieses Materials, für das Gebiet südlich von 20° Nordbreite und die Messungen bis 1937, geschieht im Rahmen des Meteorwerkes, in Band XVI als Fortsetzung von Band XV-Kriegsereignisse und Schwierigkeiten der Nachkriegszeit haben die Veröffentlichung leider stark verzögert. Für die vorliegende Mitteilung werden einige Teilergebnisse ausgewählt, die sich auf den Seeweg nach Südamerika beziehen; als Beitrag zur Gewinnung erforderlicher quantitativer Daten über die allgemeine Zirkulation.Für die Höhenstufen 4–5, 9–10 und 14–15 km werden die mittleren Windelemente und die Streuung der Windgeschwindigkeiten behandelt. Es wird die Schichtung der Luftströmungen im Vertikalprofil des Seeweges für 0–15 km Höhe gegeben. Auf die Struktur des Urpassates (der tropischen Ostströmung) und der tropischen Westwindschicht der hohen Troposphäre in den verschiedenen Jahreszeiten wird näher eingegangen.
Summary By the German Atlantic Expedition on the «Meteor», 1925–1927, and the marine-aerological work of the Deutsche Seewarte numerous upper air wind measurements were gained from the Atlantic. The evaluation of this material for the area in the south of 20° northern latitude and of the measurements up to 1937 is done within the scale of the «Meteorwerk», vol. XVI as a continuation of vol. XV. In consequence of war events and the difficulties of the time after the war the publication has been delayed considerably. For the information on hand, some partial results are selected which refer to the route to South America; as a contribution for gaining necessaryquantitative data on the general circulation.For the levels 4–5, 9–10, and 14–15 km the average wind elements and the dispersion of the wind velocities are treated. The stratification of air currents in the vertical profile of the route is given for the height of 0–15 km. It is entered into particulars of the structure of the «Urpassat» (tropical easterlies), and the tropical West-wind layer of the upper troposphere in various seasons.
  相似文献   
985.
Summary The chief object treated here relates to the proposals of the author, to modify the wellknown thread-pendulum apparatus (FP), constructed byBessel 1826 at Königsberg, aiming at the introduction of modern physical methods and materials. This method seems to be the single one comparable in exactitude with reversion pendulum (RP). Further more the free fall method (FF) has been shortly discussed with regard to the expectable mean errors, for purpose of comparison with the two others. The FF-method seems not to be able to control the RP-measurements.
Résumé L'objet principal de l'article se rapporte à des propositions de l'auteur ayant le but de modifier le bienconnu appareil à fil (FP), construit parBessel en 1826 à Königsberg. Les propositions tendent à l'introduction de méthodes et de matériaux physiques modernes. La méthode est probablement la seule comparable en exactitude aux pendules de reversion (RP). En outre la méthode de la chute libre (FF) a été discutée relativement aux erreurs moyennes expectables, au but de la comparaison avec les deux autres. La méthode FF est trouvée incapable à contrôler les mesures RP.
  相似文献   
986.
Riassunto Si discutono le diverse formule che permettono il calcolo, con i dati macrosismici, delle profondità ipocentrali dei terremoti e dei coefficienti di assorbimento delle zone interessate. Si indicano delle modifiche, nella conduzione dei calcoli richiesti dalla formula delKövesligethy, apportanti notevoli semplificazioni ai calcoli stessi. In base ai metodi indicati vengono studiati i terremoti della regione etnea e particolarmente di quella orientale. Per le profondità ipocentrali i valori ottenuti, compresi fra 0.1 e 2.5 Km, confermano le idee che si hanno sulla genesi dei terremoti della zona. Per i coefficienti di assorbimento invece i risultati, compresi fra 0.03 e 0.35, hanno permesso, di trovare una legge di variazione del coefficiente stesso con la profondità, legge che per la bassa regione orientale ha l'espressione seguente: (x)=0.27e –3.5x.
Summary They discuss the various formulae which enable to calculate, by means of the macrosismical data, the ipocentral earthquake depths and the absorption coefficients. They propose some modifications in the calculus required by theKövesligethy formula, which simplify considerably these calculations. On the basis of the indicated methods, the earthquakes of the Aetna area, especially those of the eastern side, are examined. The values obtained for the ipocentral depths, comprised between 0.1 and 2.5 Km, confirm the opinion they have on the origin of the earthquakes of this area. On the contrary the results for the absorption coefficients comprised between 0.03 and 0.35 enabled to find a variation law of this coefficient with the depth. For the low eastern region this law has the following form: (x)=0.27e –3.5x.
  相似文献   
987.
Summary The artificial moon, projected from serious scientists, presents, whenever previously without reality, a field of interesting theoretical problems. At first the figure of movement of the body itself within the varying gravity field, further more its observation by angles and distances relative to earth's body and to sky and the possible reconclusions to earth's figure and to natural moons movement. The latter beeing in a too far distance from the earth, the former surely will help to solve different problems of geodesy and astronomy.
Résumé La Lune artificielle, comme projet d'une science sérieuse moderne, présente, quand même préalablement sans réalité, un grand nombre de problèmes théoriques intéressantes. Avant tout la figure elle même de sa route dans le champs variant de la gravité et de la force centrifuge, de plus l'observation par angles et distances relatives à la terre et au ciel, et les reconclusions à la figure de la terre et au mouvement de la Lune naturelle. Cette dernière se trouvant perpétuellement dans une position de distance trop grande, la première peut aider sans doute la solution de problèmes différents de géodésie et astronomie.
  相似文献   
988.
The impact of realistic representation of sea surface temperature (SST) on the numerical simulation of track and intensity of tropical cyclones formed over the north Indian Ocean is studied using the Weather Research and Forecast (WRF) model. We have selected two intense tropical cyclones formed over the Bay of Bengal for studying the SST impact. Two different sets of SSTs were used in this study: one from TRMM Microwave Imager (TMI) satellite and other is the weekly averaged Reynold’s SST analysis from National Center for Environmental Prediction (NCEP). WRF simulations were conducted using the Reynold’s and TMI SST as model boundary condition for the two cyclone cases selected. The TMI SST which has a better temporal and spatial resolution showed sharper gradient when compared to the Reynold’s SST. The use of TMI SST improved the WRF cyclone intensity prediction when compared to that using Reynold’s SST for both the cases studied. The improvements in intensity were mainly due to the improved prediction of surface latent and sensible heat fluxes. The use of TMI SST in place of Reynold’s SST improved cyclone track prediction for Orissa super cyclone but slightly degraded track prediction for cyclone Mala. The present modeling study supports the well established notion that the horizontal SST gradient is one of the major driving forces for the intensification and movement of tropical cyclones over the Indian Ocean.  相似文献   
989.
990.
Magnetometer array studies have led to the discovery and mapping of the Southern Cape Conductive Belt (SCCB) crossing the southern tip of Africa from west to southeast coasts. The SCCB lies just south of the Namaqua-Natal Belt of cratonic rocks remobilized about 1000 m.y. B.P. It is shown that it coincides with a zone of weakness which has been exploited by three major geosynclinal accumulations over some 600 m.y. Relationships between the SCCB and the basement geochronology, geology and tectonics are considered in detail. These relationships support the view that the conductive belt was formed by an accumulation of marine sediments and oceanic lithosphere at the top of a Proterozoic subduction which stopped about 1000 to 800 m.y. B.P. Associated with this subduction we propose a Proterozoic range of Andean mountains, whose roots are now exposed in the Namaqua-Natal Belt. Later subduction further south, near the present south coast, is proposed to account for the intrusion, between the south coast and the SCCB, of the Cape Granites in the time interval 600-500 m.y. B.P. There is some evidence for a third, yet more distant, subduction episode off Permian Gondwanaland. After outlining this tectonic history, the paper turns to a closer examination of the hypothesis that the Southern Cape Conductive Belt consists of partly serpentinized basalt accumulated at the top of a Proterozoic subduction. A large static magnetic anomaly, which correlates with the SCCB over most of its length, is well fitted by a model which strongly supports this hypothesis. Bouguer gravity anomalies along western and central profiles likewise support the hypothesis. A discussion follows of the process of formation of the proposed block of serpentinized marine rocks, beginning with serpentinization of the crust near oceanic ridges by reaction of warm, porous, newly-extruded basalt with seawater convecting through it. The serpentinized basalt is stable at crustal temperatures and pressures and so is transported in the seafloor until it reaches a subduction, where it accumulates because of its low density. Examples of such accumulations are cited. Finally, it is shown that any iron in the olivine and pyroxene in the original basalt precipitates, when these silicates are hydrated to serpentine, as magnetite which is the dominant mineral conferring high electrical conductivity and high magnetic susceptibility on serpentinites. In particular the Beattie static magnetic anomaly requires, in our model calculation, a very high susceptibility readily attainable in basalt at 15–20% serpentinization. The authors know of no other rock able to provide this high susceptibility. A similar percentage of serpentinization provides the density required to model the gravity anomalies.  相似文献   
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