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51.
Peter Habison Christian Gottfried Heinz Oberhummer 《Astrophysics and Space Science》2000,273(1-4):163-170
The paper describes the European System for Particle and AstrophysicalCyber Education (ESPACE). After a general introduction to the projectand its ideas the contents of the multimedia teaching and learning systemare presented. It is followed by a discussion about the didactical aspectsof modern multimedia technology related to the project. Finally themultimedia and programming structures are explained and futureperspectives are given. 相似文献
52.
The comparison of macroseismic intensity scales 总被引:5,自引:1,他引:4
The number of different macroseismic scales that have been used to express earthquake shaking in the course of the last 200 years
is not known; it may reach three figures. The number of important scales that have been widely adopted is much smaller, perhaps
about eight, not counting minor variants. Where data sets exist that are expressed in different scales, it is often necessary
to establish some sort of equivalence between them, although best practice would be to reassign intensity values rather than
convert them. This is particularly true because difference between workers in assigning intensity is often greater than differences
between the scales themselves, particularly in cases where one scale may not be very well defined. The extent to which a scale
guides the user to arrive at a correct assessment of the intensity is a measure of the quality of the scale. There are a number
of reasons why one should prefer one scale to another for routine use, and some of these tend in different directions. If
a scale has many tests (diagnostics) for each degree, it is more likely that the scale can be applied in any case that comes
to hand, but if the diagnostics are so numerous that they include ones that do not accurately indicate any one intensity level,
then the use of the scale will tend to produce false values. The purpose of this paper is chiefly to discuss in a general
way the principles involved in the analysis of intensity scales. Conversions from different scales to the European Macroseismic
Scale are discussed. 相似文献
53.
Large data sets covering large areas and time spans and composed of many different independent sources raise the question
of the obtained degree of harmonization. The present study is an analysis of the harmonization with respect to the moment
magnitude M
w within the earthquake catalogue for central, northern, and northwestern Europe (CENEC). The CENEC earthquake catalogue (Grünthal
et al., J Seismol, 2009) contains parameters for over 8,000 events in the time period 1000–2004 with magnitude M
w ≥ 3.5. Only about 2% of the data used for CENEC have original M
w magnitudes derived directly from digital data. Some of the local catalogues and data files providing data give M
w, but calculated by the respective agency from other magnitude measures or intensity. About 60% of the local data give strength
measures other than M
w, and these have to be transformed by us using available formulae or new regressions based on original M
w data. Although all events are thus unified to M
w magnitude, inhomogeneity in the M
w obtained from over 40 local catalogues and data files and 50 special studies is inevitable. Two different approaches have
been followed to investigate the compatibility of the different M
w sets throughout CENEC. The first harmonization check is performed using M
w from moment tensor solutions from SMTS and Pondrelli et al. (Phys Earth Planet Inter 130:71–101, 2002; Phys Earth Planet Inter 164:90–112, 2007). The method to derive the SMTS is described, e.g., by Braunmiller et al. (Tectonophysics 356:5–22, 2002) and Bernardi et al. (Geophys J Int 157:703–716, 2004), and the data are available in greater extent since 1997. One check is made against the M
w given in national catalogues and another against the M
w derived by applying different empirical relations developed for CENEC. The second harmonization check concerns the vast majority
of data in CENEC related to earthquakes prior to 1997 or where no moment tensor based M
w exists. In this case, an empirical relation for the M
w dependence on epicentral intensity (I
0) and focal depth (h) was derived for 41 master events, i.e., earthquakes, located all over central Europe, with high-quality data. To include
also the data lacking h, the corresponding depth-independent relation for these 41 events was also derived. These equations are compared with the
different sets of data from which CENEC has been composed, and the goodness of fit is demonstrated for each set. The vast
majority of the events are very well or reasonably consistent with the respective relation so that the data can be said to
be harmonized with respect to M
w, but there are exceptions, which are discussed in detail. 相似文献
54.
The catalogue by Grünthal et al. (J Seismol 13:517?C541, 2009a) of earthquakes in central, northern, and north-western Europe with M w????3.5 (CENEC) has been expanded to cover also southern Europe and the Mediterranean area. It has also been extended in time (1000?C2006). Due to the strongly increased seismicity in the new area, the threshold for events south of the latitude 44°N has here been set at M w????4.0, keeping the lower threshold in the northern catalogue part. This part has been updated with data from new and revised national and regional catalogues. The new Euro-Mediterranean Earthquake Catalogue (EMEC) is based on data from some 80 domestic catalogues and data files and over 100 special studies. Available original M w and M 0 data have been introduced. The analysis largely followed the lines of the Grünthal et al. (J Seismol 13:517?C541, 2009a) study, i.e., fake and duplicate events were identified and removed, polygons were specified within each of which one or more of the catalogues or data files have validity, and existing magnitudes and intensities were converted to M w. Algorithms to compute M w are based on relations provided locally, or more commonly on those derived by Grünthal et al. (J Seismol 13:517?C541, 2009a) or in the present study. The homogeneity of EMEC with respect to M w for the different constituents was investigated and improved where feasible. EMEC contains entries of some 45,000 earthquakes. For each event, the date, time, location (including focal depth if available), intensity I 0 (if given in the original catalogue), magnitude M w (with uncertainty when given), and source (catalogue or special study) are presented. Besides the main EMEC catalogue, large events before year 1000 in the SE part of the investigated area and fake events, respectively, are given in separate lists. 相似文献
55.
G. Kruspe 《Boundary-Layer Meteorology》1974,6(1-2):257-267
Mean spectra of vertical wind velocity, temperature, and humidity and co-spectra of vertical turbulent heat and moisture fluxes are reported, normalized in terms of the similarity theory of Monin-Obukhov. The measurements were made in April 1967 at light-house Alte Weser at a height of 30 m above the German Bight. Ten spectra measured under conditions of moderate instability (z/L –0.08) have been used for the evaluation of a mean spectral curve. The humidity fluctuations have been determined from simultaneous turbulence measurements of temperature and radiorefractive-index, which were obtained by a microwave refractometer.Similar to the BOMEX measurements discussed by Phelps and Pond (1971) our results also show a dissimilarity between the fluctuations of temperature and humidity. Accordingly, in the range of lower and higher natural frequencies, significant differences were present between the co-spectra of the vertical heat and moisture fluxes, although the mean peak frequencies of both the fluxes nearly correspond to that of the mean vertical wind-velocity spectrum (f
m 0.35). 相似文献
56.
Robert Andritschke Andreas Zoglauer Gottfried Kanbach Peter F. Bloser Florian Schopper 《Experimental Astronomy》2005,20(1-3):395-403
MEGA, short for Medium Energy Gamma-ray Astronomy, is the development of a new technology telescope in the energy band 0.4--50\ MeV. The wide energy range of MEGA, which spans nuclear γ-ray lines and energetic continuum spectra, the large field of view, and the capacity for polarimetry enables unique investigations into cosmic nucleosynthesis, particle accelerators around compact objects, and explosive high-energy events. We describe the development and tests of a prototype detector. Results from laboratory tests using radioactive sources and from a beam test calibration are presented and an outlook of a potential space mission is sketched. 相似文献
57.
58.
We have speculated on the influence of organic material on extinction and absorption coefficients and liquid water content of fogs and of clouds immediately after their condensational stage. It results therefore, that the reduction of the speed of growth from fog to cloud droplets due to the presence of organic films largely reduces the properties mentioned. Compared to that their increase coming from the surface tension reduction due to organic material being dissolved or building up films is expected to be less effective. 相似文献
59.
In an earlier paper (1978), Gottfried presented a method for combining distribution data for float-sink coal-cleaning devices into a single generalized distribution curve which, for a given device and feed size, is independent of specific gravity of separation. A non-linear, exponential-type equation was utilized to represent the generalized distribution curve, along with the corresponding generalized probable error. Distribution data for six common coal-cleaning devices have previously been treated by this method.This paper is an extension of two previous studies (Gottfried, 1978, 1980). The method described above is applied to three different float-sink coal-cleaning devices: Baum jig (replacing previously reported results), Batac jig and Dynawhirlpool separator. Results for the Baum jig and Batac jig reflect a two-stage separation process, with a set of generalized distribution curves obtained for each stage and another set for the overall separation. Several different feed size fractions are given for each vessel. 相似文献
60.
Dr. Gottfried Kneuper 《International Journal of Earth Sciences》1960,50(1):442-449
Zusammenfassung Im bergbaulich erschlossenen Gebiet mit seinen guten Untertageaufschlüssen können verschiedene tektonische Baustile beobachtet werden, welche eine Gliederung in große Schollen zulassen. In den aufschlußärmeren Gebieten sind die Schollenränder nur mit Vorsicht festgelegt. Die Kennzeichen des Baustiles von der Scholle des Saarbrücker Hauptsattels werden jenen von den Nachbargebieten gegenübergestellt. 相似文献