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951.
J. Trčková 《Environmental Geology》1998,35(4):245-250
Experimental modelling methods are used for prediction of deformation and groundwater outflows at the bottom of an open-pit
mine during the excavation of brown coal. Thermal gas-bearing artesian water exerts an uplift pressure on the impervious subsoil
of the coal seam and threatens the stability of the mine bottom. The breakthrough of the mine bottom would seriously affect
the groundwater regime and may endanger mining activities. The mining is carried out within the protection zones of the Carlsbad
spa springs. Results of model studies are used to determine protective hydrogeological and mining measures for providing the
maximum protection for the open-pit mine and the spa springs.
Received: 16 August 1996 · Accepted: 9 June 1997 相似文献
952.
Jaroslav Souček 《Astrophysics and Space Science》1987,137(2):347-356
There is a brightening effect of quasar outputs due to the positive curvature of space in the static Universe, if we use the right expression of distance as an arc3r=R
, and not the corrected luminosity distance ofr=Rsin. 相似文献
953.
Pavel Voráček 《Astrophysics and Space Science》1985,111(1):103-121
In some few steps a model describing the physical character of the cosmological expansion of the Friedmann-Robertson-Walker closed universe is developed. Due to the fact that the rate of the cosmic time is changing, the conclusion is drawn that a hidden expansion is superposed on the generally known expansion of the Universe. The resulting picture-the bi-expansive model-is brought into connection with the voids in the Universe.The expansion is described as a motion in a spatial dimension orthogonal to our space-the 4-dimensional sphere, and some characteristic properties of such a motion, compatible with the special and general relativity, are outlined. The question of the world-force retarding the expansion is touched upon, and the concepts of contemporaneity and distance in cosmology are specified. Some attempts to a physical explanation of the connection between the voids and the bi-expansive model are given in the Appendix. Also in the Appendix the Friedmann equation is rather unconventionally used for a deduction of the value of the Hubble constant as a function of distance. 相似文献
954.
V. A. Vujičić 《Celestial Mechanics and Dynamical Astronomy》1988,44(1-2):45-48
The differential equations of the self-rotation of a celestial body have been evaluated. From an integral of these equations a formula for angular velocity of the celestial body was obtained. This formula after being applied to the rotation of the Sun and of the Earth gives, respectively, the following angular velocity ranges: 0.588×10–6<<18, 187×10–6 and 0.7533×10–5<<12,4266×10–5. These are up to three times narrower than those previously obtained by Savi and Kaanin [1]. 相似文献
955.
Michal Bíl Richard Andrášik Pavel Zahradníček Jan Kubeček Jiří Sedoník Petr Štěpánek 《Landslides》2016,13(2):337-347
Shallow landslides are fairly frequent natural processes which emerge as a result of both rainfall and rapid snowmelt in the Flysch Belt of the Outer Western Carpathians. We estimated the total water content thresholds for the previously defined seven phases of increased landsliding which took place between 1939 and 2010 around the Napajedla meteorological station. The time series were reconstructed on the basis of data from surrounding stations. Rainfalls with the highest intensities (>1 mm/min) were removed from the set. Rainfall of such an intensity primarily causes overland flow and soil erosion and does not contribute to landslide threshold. The snow water equivalent was computed on the basis of the snow height, and possible errors were evaluated as interval estimations. An interval of 10 days before a landslide phase was selected for the total water content threshold. The resulting lower boundary (67.0 mm/10 days) and upper boundary (163.3 mm/10 days) thresholds of water infiltrated into soil during an event shall be part of the prepared online warning system in this area. 相似文献
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