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991.
A. Claverie G. R. Isaak C. P. McLeod H. B. Van Der Raay T. Roca Cortès 《Solar physics》1981,74(1):51-57
The discrete structure in the 5 min velocity oscillations of the solar surface has been confirmed by a re-analysis of data obtained between 1976 and 1979, and in addition a preliminary analysis of 1980 data show excellent consistency of the determined frequencies over the five year period. It is further shown that atmospheric transparency, as measured by the power in the solar intensity fluctuations, shows no correlation with the measured amplitude of the velocity fluctuations, over 2 orders of magnitude.Proceedings of the 14th ESLAB Symposium on Physics of Solar Variations, 16–19 September 1980, Scheveningen, The Netherlands. 相似文献
992.
André Deprit 《Celestial Mechanics and Dynamical Astronomy》1979,20(4):325-327
An inductive algorithm is proposed to solve Lagrange's implicit equation when its right hand member is a power series in the small parameter. 相似文献
993.
Bálint Érdi 《Celestial Mechanics and Dynamical Astronomy》1982,28(1-2):209-218
Szebehely's equation for the potential generating a prescribed family of orbits in two dimensions is generalized for three-dimensional orbits. A simultaneous system of first-order linear partial differential equations is derived for the determination of the potential in the three-dimensional case. Solutions of this system are found in several cases including Kepler's problem too.Paper presented at the 1981 Oberwolfach Conference on Mathematical Methods in Celestial Mechanics.This paper is dedicated to Professor Victor Szebehely on the occasion of his 60th birthday. 相似文献
994.
SPLITTING OF CALIBRATION DATA BY CLUSTER ANALYSIS 总被引:1,自引:0,他引:1
from eorresponding valuesof x.The most eommon aPProaeh to this Problem 15 linear regression(or ealibration),but1 inear methods are usually best suited for quite limited regions alld are not generallyaPPlieable.If a linear fit 15 not satisfactory,alternative aPProaehes are non一linear regression,non一Parametrie regression,transformations and sPlitting of the data into subgrouPs 相似文献
995.
For 181 PCA's recorded during the years 1956–1969 the association with flares is studied. Both the number of events which
cannot be associated with any flare on the visible hemisphere, as well as the longitude distribution of identified proton
flares, lead to the conclusion that 25–30% of PCA's are caused by flares behind the western solar limb. PCA's of this kind
are mostly small. During the investigated years no PCA > 13 dB and possibly no PCA > 8.5 dB were caused by flares behind the
limb, while hardly 60% of PCA's < l dB had their origin on the visible hemisphere.
While the sources of GLE's and of PCA's in general, are centered around 50°W which corresponds to the average curvature of
the magnetic field lines in interplanetary space, the strongest PCA's (> 8.5 dB) show an anomalous longitude distribution
centered around ∼ 20°W. It is suggested that this anomaly may be a consequence of the fact that in strong PCA events the kinetic
energy density of protons below 100 MeV becomes comparable to the magnetic energy density in space, thus leading to a ‘straightening’
of the magnetic field lines. 相似文献
996.
Pavel Voráček 《Astrophysics and Space Science》1989,155(2):341-343
An idea is put forward that the events considered in the non-locality phenomenon are co-local and simultaneous in the reference frame of information moving with the velocity of light. Then, the special relativity can explain many aspects of the issue. Furthermore, the impact of the idea is discussed in relation to problems of the Mach principle and those of the Planck era connected to the closeness or openess of our Universe. 相似文献
997.
Beatriz García Carlos Hernández Stella Malaroda Nidia Morrell Hugo Levato 《Astrophysics and Space Science》1988,148(1):163-173
We determined radial velocities for 25 probable members of the open cluster IC 2602. We identified the stars with variable radial velocity. We improved the orbit of HD 93030, and computed a preliminary orbit for another spectroscopic binary. We discussed with such data the average cluster radial velocity and we compare the incidence of short period binaries among the Main-Sequence members of IC 2602 with the incidence for other clusters with different values of the average axial rotation of their members.Cerro Tololo Interamerican Observatory operated by the Association of Universities for Research in Astronomy, Inc., under contract with the National Science Foundation. 相似文献
998.
José?Badalmiguelvb@unizar.es" title="badal@unizar.es miguelvb@unizar.es" itemprop="email" data-track="click" data-track-action="Email author" data-track-label="">Email author Miguel?Vázquez-prada álvaro?González 《Natural Hazards》2005,34(3):353-374
Prognostic estimations of the expected number of killed or injured people and about the approximate cost associated with the damages caused by earthquakes are made following a suitable methodology of wide-ranging application. For the preliminary assessment of human life losses due to the occurrence of a relatively strong earthquake we use a quantitative model consisting of a correlation between the number of casualties and the earthquake magnitude as a function of population density. The macroseismic intensity field is determined in accordance with an updated anelastic attenuation law, and the number of casualties within areas of different intensity is computed using an application developed in a geographic information system (GIS) environment, taking advantage of the possibilities of such a system for the treatment of space-distributed data. The casualty rate, defined as the number of killed people divided by the number of inhabitants of the affected region, is also computed and we show its variation for some urban concentrations with different population density. For a rough preliminary evaluation of the direct economic cost derived from the damages, equally through a GIS-based tool, we take into account the local social wealth as a function of the gross domestic product of the country. This last step is performed on the basis of the relationship of the macroseismic intensity to the earthquake economic loss in percentage of the wealth. Such an approach to the human casualty and damage levels is carried out for sites near important cities located in a seismically active zone of Spain, thus contributing to an easier taking of decisions in emergency preparedness planning, contemporary earthquake engineering and seismic risk prevention. 相似文献
999.
Summary Metamorphosed carbonatites and related skarn deposits, located in Fuerteventura Basal Complex, contain unusual Sr-rich minerals. Maximum SrO concentration in the following minerals are: calcite, 7.23wt%; apatite, 5.22wt%; epidote, 11.64wt%; clinozoisite, 1.25wt%; allanite, 5.63wt%; britholite, 4.11wt% and a Sr–Na aluminosilicate (probably stronalsite), 16.44wt% SrO. Calcite and apatite are chemically similar to those found in carbonatites and are therefore considered to be of igneous origin. Textural evidence indicates that the first skarn stage garnet+diopside+Sr–Na aluminosilicate formed as the result of chemical interaction between carbonatites and adjacent silicate rocks. The formation of Sr-bearing epidote/clinozoisite, allanite and britholite appears to be related to the release of Sr into the fluid phase from the breakdown of high temperature assemblages during the retrograde skarn stage. During the final evolution stages, further alteration of britholite by bastnäsite and törnebohmite took place. The occurrence of REE minerals shows that the fluids responsible for this metasomatism must also have transported significant quantities of REE. 相似文献
1000.
This paper shows the results of a ground magnetic survey carried out to study solid waste landfills. The area located southward of Gualeguaychú town was chosen as a pilot case. This zone was selected considering the available knowledge about the cessation of operations, and the interest of the local authorities in verifying the existence of anomalies indicative of possible dangerous pollutants. The total magnetic field was measured along six profiles, and the corresponding anomalies were calculated. The profiles were modelled in 2.5 D, and along them Eulers deconvolution was used to estimate the depth to the sources. The first and the second derivatives of the residual magnetic field were calculated, in order to sharpen the anomalies. Our interpretation suggests that the characteristics of the modelled bodies and the magnitudes of the detected anomalies do not indicate the presence of drums in the sanitary infill. 相似文献