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111.
112.
G. Imbò 《Bulletin of Volcanology》1949,8(1):119-122
113.
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
114.
Journal of Oceanology and Limnology - Three species of dinophysoid planktonic dinoflagellates are described from the eastern Mediterranean Sea. Amphisolenia sp. aff. brevicauda was collected at... 相似文献
115.
A semi-numeric method was used to study the evolution of a general-relativistic radiating shell in its Post-Newtonian and
Newtonian approximations. The solutions, where the main parameters are given reasonable values, show that a relativistic effect
can be found in X-ray-burster-like objects.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
116.
Abstract. A total of 1789 fish belonging to 38 families and 73 species were collected at depths between 18 and 1102 m during 216 bottom longline operations off Lanzarote and Fuerteventura, Canary Islands, between February 1994 and December 1995. For each species the depth distribution is provided. Length-weight and depth-size relationships are reported for three shelf-dwelling species. The bigger-deeper relationship found in two of them contrasts with the bigger-shallower pattern of the deeper living trichiurid Lepidopus caudatus . In November 1997, nine additional bottom longline operations were carried out off eastern Fuerteventura at depths between 805 and 1217 m. In this area, after earlier studies in October 1995, a spawning aggregation of the morid Mora moro was encountered for the second time. The catches of 1997 revealed a strongly male-biased sex ratio. Also, the males showed a significantly lower gonadosomal index than two years earlier. These findings indicate slight interannual variations in reproductive timing and an earlier arrival of male Mora moro at the spawning grounds. Clear variations in the number of fish collected at adjacent sites possibly reflect a preference for distinct microhabitats. Preliminary evidence of local upwelling of cold water above the spawning grounds is provided by satellite imagery. 相似文献
117.
Band-limited functions on a bounded spherical domain: the Slepian problem on the sphere 总被引:2,自引:1,他引:1
The Slepian problem consists of determining a sequence of functions that constitute an orthonormal basis of a subset of ℝ
(or ℝ2) concentrating the maximum information in the subspace of square integrable functions with a band-limited spectrum. The same
problem can be stated and solved on the sphere. The relation between the new basis and the ordinary spherical harmonic basis
can be explicitly written and numerically studied. The new base functions are orthogonal on both the subspace and the whole
sphere. Numerical tests show the applicability of the Slepian approach with regard to solvability and stability in the case
of polar data gaps, even in the presence of aliasing. This tool turns out to be a natural solution to the polar gap problem
in satellite geodesy. It enables capture of the maximum amount of information from non-polar gravity field missions.
Received: 10 June 1998 / Accepted: 20 May 1999 相似文献
118.
119.
Instability in spatial error models: an application to the hypothesis of convergence in the European case 总被引:1,自引:1,他引:0
This paper focuses on the hypothesis of stability in the mechanisms of spatial dependence that are usually employed in spatial
econometric models. We propose a specification strategy for which the first step is to solve a local estimation algorithm,
called the Zoom estimation. The aim of this stage is to detect problems of heterogeneity in the parameters and to identify
the regimes. Then we resort to a battery of formal Lagrange Multipliers to test the assumption of stability in the processes
of spatial dependence. The alternative hypothesis consists of the existence of several regimes in these parameters. A small
Monte Carlo serves to confirm the behaviour of this strategy in a context of finite size samples. As an illustration, we solve
an application to the case of the hypothesis of convergence for the per capita income in the European regions. Our results
reveal the existence of a strong Centre-Periphery dichotomy in which instability extends to all the elements (coefficients
of regression as well as parameters of spatial dependence) that intervene in a classical conditional β-convergence model. 相似文献
120.