Основание чехословацкого метеорологического оБщества     

Mikuláš Konček 《Studia Geophysica et Geodaetica》1959,3(3):295-295

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La loi de danjon et les eruptions volcaniques     

F. Link 《Earth, Moon, and Planets》1974,11(3-4):261-272

Résumé La loi de Danjon qui décrit les variations de la luminosité des éclipses de Lune au cours du cycle solaire de 11 ans, a été vérifiée dans 7 cas des minima solaires entre 1900 et 1965, dont deux peuvent être attribués aussi à l'activité volcanique.

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Danjon's law describing the variations of the luminosity of lunar eclipses during the 11 year cycle of solar activity has been verified in 7 cases between 1900 and 1965 from which 2 cases may be also ascribed to the volcanic activity.

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Optimum nets     

Lubomír Kubáček  Andrej Pázman  Reviewer B. Delong 《Studia Geophysica et Geodaetica》1974,18(2):91-102

Summary Within a given configuration of points of a geodetic net measurements may be carried out according to different designs. The selected design generates a certain value of the determinant of the covariance matrix of the estimate of the net parameters being determined. Of two designs which both require the same number of measurements, that which generates a smaller value of the determinant of the covariance matrix is considered the better. The paper describes the procedure which determines the best design by method of iteration, or determines the design which differs from the best negligibly.  相似文献   

Conditions de visibilité du satellite artificiel     

František Link 《Studia Geophysica et Geodaetica》1957,1(1):114-123

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Roe Deer Antlers as a Historical Bioindicator of Lead Pollution in the Šalek Valley, Slovenia     

B. Pokorny  A. Glinšek  C. Ribarič-Lasnik 《Journal of Atmospheric Chemistry》2004,49(1-3):175-189

Antlers of different deer species are of particular importance for assessing temporal and/or spatial variations in environmental pollution with bone-seeking pollutants, such as Pb. Since antlers have a well-defined annual growth cycle, they accumulate Pb during a seasonally fixed time span, which provides natural standardisation of samples. Moreover, they are kept as trophies in well-dated collections enabling their use in historical studies. Considering these benefits, Pb levels were determined (by inductively coupled plasma mass spectrometry after the wet digestion of samples) in 116 antlers of roe deer (Capreolus capreolus L.), shot in the period 1961–2002 in the vicinity of the largest Slovene thermal power plant of otanj (TPP). Irrespective of the year of antler growth and the age of the animal analysed (no age-dependent influences were revealed), Pb levels ranged from 0.20 to 7.28 mg kg^–1 (mean: 1.32 ± 0.19 mg kg^–1), with the highest contents in the oldest and the lowest contents in the most recent samples. Since the mid-1960s, lead pollution has continuously decreased in the study area; three very evident drops (after 1975, 1985 and 1995, respectively) indicate the combined effect of three different remediation measures as follows: construction of a remote heating system in the seventies; introduction of unleaded petrol in the late-1980s, and construction of clean-up devices at the TPP in the late-1990s. The high positive correlation between the annual emissions from the TPP and the mean yearly Pb levels in antlers showed that roe deer antlers may be an useful tool for assessing temporal trends of ambient Pb pollution.  相似文献   

Aqueous Oxidation of Sulfur(IV) Catalyzed by Manganese(II): A Generalized Simple Kinetic Model     

Boštjan Podkrajšek  Gorazd Berčič  Janja Turšič  Irena Grgić 《Journal of Atmospheric Chemistry》2004,47(3):287-303

The reaction kinetics of S(IV) autoxidation catalyzed by Mn(II) in the pH range 3–5 typical for atmospheric liquid water, was investigated. For reactions with pH maintained constant during the reaction course, the predictions obtained by a simple integral approach cover kinetic results only for concentrations of HSO ₃ ⁻ up to 0.2 mM at pH 4.5. Thus, a generalized simple kinetic model, which can be used for predicting the reaction kinetics in wider concentration, pH and temperature ranges, was derived. This model is based on the assumption that the reaction rate is proportional to the concentration of a transient manganese-sulfito complex formed in the initial step of a radical chain mechanism. In the proposed power law rate equation the concentration of complex is calculated from the stability constant K and concentrations of reactants at a specific reaction time. This rate equation adequately predicts the reaction kinetics in the pH range 3–5, in the concentration ranges 0.1 ≤ [HSO ₃ ⁻ ] ≤ 0.4 mM and 2 ≤ [Mn(II)] ≤ 14.6 μM. For the temperature range 15–35 °C, the estimated value for activation energy is 92.0 ± 0.1 kJ mol⁻¹ and the Gibbs free energy of formation of the manganese-sulfito complex is −20.4 ± 0.3 kJ mol⁻¹. Furthermore, the kinetics for catalytic reactions with pH maintained constant during the reaction course as well as with initial pH adjusted only at the start of the reaction, is described satisfactorily by the present model.  相似文献   

Statistical Interpretation of Webnet Seismograms By Artificial Neural Nets     

Plešinger  Axel  Růžek  Bohuslav  Boušková  Alena 《Studia Geophysica et Geodaetica》2000,44(2):251-271

We employed multilayer perceptrons (MLP), self organizing feature maps (SOFM), and learning vector quantization (LVQ) to reveal and interpret statistically significant features of different categories of waveform parameter vectors extracted from three-component WEBNET velocigrams. In this contribution we present and discuss in a summarizing manner the results of (i) SOFM classification and MLP discrimination between microearthquakes and explosions on the basis of single-station spectral and amplitude parameter vectors, (ii) SOFM/LVQ recognition of initial onset polarities from PV'-waveforms, and (iii) a source mechanism study of the January 1997 microearthquake swarm based on SOFM classification of combined multi-station PV-onset polarity and SH/PVamplitude ratio (CPA) data. Unsupervised SOFM classification of 497 NKC seismograms revealed that the best discriminants are pure spectral parameter vectors for the recognition of microearthquakes (reliability 95% with 30 spectral parameters), and mixed amplitude and spectral parameter vectors for the recognition of explosions (reliability 98% with 41 amplitude and 30 spectral parameters). The optimal MLP, trained with the standard backpropagation error method by one randomly selected half of a set of 312 mixed (7 amplitude and 7 spectral) single-station (NKC) microearthquake and explosion parameter vectors and tested by the other half-set, and vice versa, correctly classified, on average, 99% of all events. From a set of NKC PV-waveform vectors for 375 events, the optimal LVQ net correctly classified, on average, 98% of all up and 97% of all down onsets, and assigned the likely correct polarity to 85% of the onsets that were visually classified as uncertain. Optimal SOFM architectures categorized the CPA parameter vector sets for 145 January 97 events individually for each of five stations (KOC, KRC, SKC, NKC, LAC) quite unambiguously and stable into three statistically significant classes. The nature of the coincidence of these classes among the stations that provided most reliable mechanism-relevant information (KOC, KRC, SKC) points at the occurence of further seven statistically significant subclassses of mechanisms during the swarm. The ten neural classes of focal mechanisms coincide fairly well with those obtained by moment tensor inversion of P and SH polarities and amplitudes extracted from the seismograms interactively. The obtained results, together with those of refined hypocenter location, imply that the focal area consisted of three dominant faults and at least seven subfaults within a volume of not more than 1 km in diameter that likely were seismically activated by vertical stress from underneath.  相似文献   

S. Horie (Ed.): History of Lake Biwa. Kyoto,Kyoto Univ., Inst. Paleolimonol. and Paleoenvironment on Lake Biwa,Contribution No. 553, 1987, p. 242, 80 figs., 12 Tab., 5 pages of color photographs     

V. Slde ek 《洁净——土壤、空气、水》1989,17(1):74-74

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The role of expansion for the entropy of the Universe     

Emil Ulrych  Pavel Voráček 《Astrophysics and Space Science》1991,186(1):157-158

Under assumption of the closed FRW-universe, the idea is presented that the cosmological expansion/contraction on its own, has an entropy balancing effectively the changing entropy of the cosmic fluid in such a way that at every epoch the total entropy of the Universe remains constant.  相似文献   

A brief outline of the magnetic susceptibility anisotropy of various rock types     

František Janák  Reviewer V. Kropáček 《Studia Geophysica et Geodaetica》1973,17(2):123-130

Summary In the first part of this paper, the main geological and geophysical applications of magnetic susceptibility anisotropy are briefly described. In the second part, the data on the magnetic anisotropy of various rock types are summarized and some conclusions concerning its significance are deduced. For this purpose, all accessible data were used.Dedicated to 90th Birthday of Professor Frantiek Fiala  相似文献