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91.
The Velenje area (almost 200 km2 with over 31,000 inhabitants) is based on the Šalek Valley, which became a leading area of industrialisation and urbanisation
after the Second World War, with consequent pollution problems. Various industrial plants polluted the river Paka while more
serious hazards arose through the coal mine which is a still causing landscape subsidence and the thermal power station in
the neighbourhood of Šoštanj which is a major source of sulphur dioxide and nitrogen oxide pollution. In 1987 there was an
ecological protest which marked the beginning of a sustainable development strategy for the community. During the past decade
programmes have dealt with the degradation of air, soil and water to achieve cleaner air, a transformation in landuse and
enhancement the river's formerly weak self-purifying capabilities. This article examines the changes in the valley since the
attention of the authorities was drawn to the deterioration of living conditions. Despite the pressures of transition which
have seen unemployment rising to over ten percent, significant environmental improvements have been made and the area stands
as a model for the rest of the country.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
92.
M. Čadež 《Pure and Applied Geophysics》1960,45(1):227-237
Summary One can find that over the continent the cold fronts becomes stationary after the sunrise. In the present paper this phenomen is explaned by heating of cold air what causes the increase of the slope of the boundary surface. Because of surface heating of the cold air the horizontal pressure gradient in direction toward the front increases with time, and so increases the transport of the cold air in this direction too. The increasing of the slope of boundary surface that is in connection with the mentioned increased trasport of cold air, causes the convergence of air mass and the ascent of it at the same front (Fig. 2).As the consequence of the heating from the surface and the liberation of latent heat of vaporisation, the volume of cold air increases. In connection with this the divergence of mass occures in the high levels and later one can find at the surface the corresponding fall of pressure. This effects can cause in suitable cases the development of cyclon, similarily as shown on Fig. 4. When the cold air comes from the cold continent over a relatively warm sea surface, the strong heating of cold air occurs and as consequence of this, the cyclogenesis. 相似文献
93.
94.
Karel Prikner Jaroslav Střeštík Karel Dobeš Reviewer M. Hvoždara 《Studia Geophysica et Geodaetica》1972,16(3):262-270
Summary The spectral analysis of samples of beating-type pc3 pulsations, recorded at the Budkov Observatory during the summer months of 1968 and 1969 was carried out in the frequency interval10 mHz100 mHz. The average limits of the pulsation frequency range are roughly20 mHz60 mHz. The centre of the occurrence frequency graphs for both components is at the frequency fg 41 mHz. The analysis of three separated daily intervals showed a very slight tendency to a systematic decrease in the frequency of the centre from the morning to the afternoon. The study of the sense of rotation of the pulsation disturbance vector in the (X, Y)-plane showed an overall predominancy of L over R-types during daytime, particularly during the morning. 相似文献
95.
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
96.
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
97.
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
98.
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
99.
Dušan Němec 《Contributions to Mineralogy and Petrology》1969,20(3):235-243
The determination of the fluorine content of courmalines yielded 0.28% as an average value for schorlites and dravites and 0.97% for elbaites. The plot of the fluorine contents against the lithium contents shows that the distribution of projection points for pink or green elbaites differs from that for lithian indigolites. Tourmalines are poorer in fluorine than lightcoloured micas at the same stage of pegmatite evolution. Individual regions with pegmatite occurrences can be characterized as rich or poor in fluorine according to the fluorine contents in the tourmalines and micas contained in the pegmatites. 相似文献
100.
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