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41.
Summary The problem of electromagnetic induction in a half-space with a cylindrical inhomogeneity is treated. Solutions for TE and TM polarization of the exciting electromagnetic field are given, which can be used for computing sounding and profiling curves. The anisotropy of the surface impedance is pointed out, as well as a whole series of other interesting properties of the magnetotelluric field in this model; some of them are also demonstrated on the computed theoretical curves. 相似文献
42.
Oldřich Praus Jindřich Rejl Reviewer M. Hvoždara 《Studia Geophysica et Geodaetica》1972,16(4):373-382
u¶rt;m mam u¶rt;au m ¶rt;a u¶rt;u ma u n aau anu mauaum n amuu ¶rt; a nu¶rt; 1967–1970. aamua ma auum m u¶rt;uu m nu¶rt;a u u am ¶rt;am a¶rt;a m mu ¶rt;¶rt;m -3 amu aua.
Dedicated to Academician Alois Zátopek on His 65th Birthday 相似文献
Dedicated to Academician Alois Zátopek on His 65th Birthday 相似文献
43.
Marjan Čadež 《Pure and Applied Geophysics》1972,93(1):187-190
Summary The forces due to compressibility of a fluid and their action on moving bodies have been studied. Also a possible practical application of these forces in a propulsion mechanism for vehicles has been discussed.
Zusammenfassung Im vorliegenden Beitrag wird die Wirkung der Kräfte auf bewegende Körper, die durch Kompressibilität des Mediums bedingt sind, untersucht. Es wird über die Möglichkeit der Konstruktion eines Mechanismus auf diesem Prinzip diskutiert.相似文献
44.
Josef Bochníček Jaroslav Šubrt Reviewer M. Hvoždara Reviewer J. Podlešák 《Studia Geophysica et Geodaetica》1971,15(1):76-85
Zusammenfassung Es wird eine Methode für experimentelle Untersuchung der Frequenzkennlinien von Induktionsvariometern mit Aufnahmeschleifen nichttraditioneller Ausmasse beschrieben. Die Grundlage des beschriebenen Verfahrens bildet eine genaue Bestimmung jenes Teils des magnetischen Kraftflusses, der durch die Aufnahmeschleife durchgeht. 相似文献
45.
Daily full-disk solar maps obtained at 37 GHz in the years 1979, 1980, 1981, 1982, 1987, 1988, 1989, 1990, and 1991 are analysed and compared with full-disk solar maps in H. A search for a difference in the measured angular rotation velocity for two classes of microwave low-brightness-temperature regions (LTRs), associated and not associated with H filaments, is performed. Procedures with and without statistical weights, assigned to angular rotation velocities according to the tracing time, are applied and the statistical significance of the results is discussed. A higher angular rotation velocity is measured for LTRs associated with H filaments than for the not-associated ones. This angular velocity difference is interpreted as a consequence of a height difference between these two types of LTR tracers. Changes of the solar differential rotation velocity during the activity cycle measured using LTRs as tracers are explained by the measured cycle-dependence of the association rate between LTRs and H filaments. Similarly, the north–south asymmetry in the solar rotation velocity measured tracing LTRs is explained by the measured north–south asymmetry in the association rate between LTRs and H filaments. The rotation velocity of LTRs and H filaments is on the average more rigid in comparison with sunspots. 相似文献
46.
K. Pandžić I. Šimunić F. Tomić S. Husnjak T. Likso D. Petošić 《Theoretical and Applied Climatology》2006,85(1-2):107-115
Summary This paper presents an the evaluation of three mathematical models for the estimation of 10-day drain discharge using weather, pedological and phenological parameters. One model uses modified Palmer’s procedure for the calculation of
water balance components and the second two use empirical multiple linear regression. The models have been applied to data
of an amelioration experimental field in central Croatia (south-western part of the Pannonian Lowland), where a set of average
10-day air temperature and relative humidity data, average wind speed, cumulative precipitation and drain discharge amounts,
insolation and soil moisture data and vegetation indices have been collected. The experiment has been performed during the
period 1990–1992. The models have been tested by comparing estimated and observed 10-day drain discharge amounts. All models
mainly give acceptable cumulative results although their accuracy depends on the season. 相似文献
47.
This paper presents the development and utilisation of an automated image processing algorithm for detection and analysis
of grains. Using optical polarising microscopy, a set of colored images are collected from an area on a thin section. A filtering
operation, using rotation of a morphological alternating sequence filter (based on a structuring element), is used to remove
twinning features within individual grains. Filtering is followed by the watershed segmentation technique to determine grain
boundaries. The method is used for the identification of calcite grains in marble and the subsequent analysis of morphological
anisotropy. 相似文献
48.
Roša D. Vršnak B. Božić H. Brajša R. Ruždjak V. Schroll A. Wöhl H. 《Solar physics》1998,179(2):237-252
The dependence of the measured apparent synodic solar rotation rate on the height of the chosen tracer is studied. A significant error occurs if the rotation rate is determined by tracing the apparent position of an object above the photospheric level projected on the solar disc. The centre-to-limb variation of this error can be used to determine simultaneously the height of the object and the true synodic rotation rate. The apparent (projected) heliographic coordinates are presented as a function of the height of the traced object and the coordinates of its footpoint. The relations obtained provide an explicit expression for the apparent rotation rate as a function of the observed heliographic coordinates of the tracer, enabling an analytic least-squares fit expression to determine simultaneously the real synodic rotation rate and the height of the tracer. 相似文献
49.
The territory of Croatia and neighboring regions is divided into 17 seismic source zones, considering available seismological
and geological data. On this basis, seismic hazard elements (seismicity rate, maximum magnitude, b-value, probabilities of
exceedance and return periods for a predefined set of magnitudes) are computed using the maximum likelihood method appropriate
for treating data-sets with variable completeness thresholds. The values of long term expected peak horizontal acceleration
obtained by using a combination of the deterministic and the probabilistic procedure are the highest in the Dubrovnik zone,
while the Zagreb zone has the highest earthquake hazard in the continental part of the country.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
50.
Electromagnetic induction of a three-dimensional conductivity inhomogeneity in the two-layered earth
Summary The calculation of the elements of Green's tensor function is presented for solving the problem of the electromagnetic induction by means of a vector integral equation. A two-layered Earth is considered as the medium, the surface layer including a three-dimensional conductivity inhomogeneity. Use is made of the boundary condition requiring the vertical component of the electric current to be zero at the Earth's surface which partly simplifies the theoretical computation. Long-period asymptotics of the individual complicated functions, occurring in Green's tensor function as well as in the tensor function required to calculate the components of the anomalous magnetic field at the surface of the halfspace, were effected. With the aid of these asymptotics one can obtain estimates of the functions occurring in the theoretical analysis of the problem. 相似文献