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101.
Density function evaluation from borehole gravity meter data – regularized spectral domain deconvolution approach 下载免费PDF全文
We present a new method of transforming borehole gravity meter data into vertical density logs. This new method is based on the regularized spectral domain deconvolution of density functions. It is a novel alternative to the “classical” approach, which is very sensitive to noise, especially for high‐definition surveys with relatively small sampling steps. The proposed approach responds well to vertical changes of density described by linear and polynomial functions. The model used is a vertical cylinder with large outer radius (flat circular plate) crossed by a synthetic vertical borehole profile. The task is formulated as a minimization problem, and the result is a low‐pass filter (controlled by a regularization parameter) in the spectral domain. This regularized approach is tested on synthetic datasets with noise and gives much more stable solutions than the classical approach based on the infinite Bouguer slab approximation. Next, the tests on real‐world datasets are presented. The properties and presented results make our proposed approach a viable alternative to the other processing methods of borehole gravity meter data based on horizontally layered formations. 相似文献
102.
Waldemar Cudny Håkan Appelblad 《Norsk geografisk tidsskrift. Norwegian journal of geography》2019,73(5):273-289
ABSTRACTThe aim of the article is to present and discuss functions of public monuments in relation to different dimensions of geographical space. The authors discuss public spaces, monuments, public art, based on a mixed-method approach and an analysis of scientific literature as the main research method. The theoretical discussion is supplemented with the results of Internet searches and an analysis of media supplements, and specific examples are given, including some from Poland. An additional method was autoethnography, which involved an analysis of cultural phenomena based on the authors’ experience. The analysis revealed that monuments were part of public art and thus enriched public spaces in cities. They fulfilled different important functions: artistic, symbolic, commemorative, political, social, religious, marketing, and mixed. Additionally, the monuments reflected the contemporary transformation of ideas and social orders and therefore also reflected contemporary urban debates. They were products of social relations, powers, ideas, identities, and the collective memory reflected in the urban spatial structure of cities. The authors conclude that the examples presented in the demonstrate that monuments perform various functions in urban public spaces. From a spatial perspective, the role of monuments depends on their different impacts on people’s perceptions and interpretations of space. 相似文献
103.
Jóźwiak Waldemar Nowożyński Krzysztof Mazur Stanisław Jeż Maciej 《Surveys in Geophysics》2022,43(5):1563-1586
Surveys in Geophysics - This paper presents a three-dimensional (3-D) model of the resistivity distribution in the European lithosphere at the junction between the East European Craton, the... 相似文献
104.
Jacek Rapinski Waldemar Kaminski Artur Janowski Wioleta Blaszczak-Bak 《Journal of the Indian Society of Remote Sensing》2011,39(4):591-597
DTM extraction from the ALS (Airborne Laser Scanning) point cloud is a complex task which involves many algorithms and numerical
procedures. One of the first steps, performed to remove all of the terrain covering, is data filtration. There is a number
of filtration methods and algorithms to chose from. In this paper we would like to propose a filtration method based on fuzzy
logic. We present basic information regarding fuzzy logic, the design of fuzzy rules and an example of point cloud processing.
For comparison, results from the ATIN filtration method are presented. 相似文献
105.
Werner L Kutsch Lutz Merbold Waldemar Ziegler Mukufute M Mukelabai Maurice Muchinda Olaf Kolle Robert J Scholes 《Carbon balance and management》2011,6(1):5
Background
This study evaluates the carbon dioxide and other greenhouse gas fluxes to the atmosphere resulting from charcoal production in Zambia. It combines new biomass and flux data from a study, that was conducted in a miombo woodland within the Kataba Forest Reserve in the Western Province of Zambia, with data from other studies. 相似文献106.
Waldemar Cudny 《Geografisk tidskrift / udgivet af Bestyrelsen for Det Kongelige danske geografiske selskab》2013,113(2):132-142
Festivals are an increasingly common phenomenon. They strongly influence geographical space, and so are studied in depth by geographers. The author shows that festivals are a subject for research in different geographical sub-disciplines. The author also defines the research paradigm of the geography of festivals as a part of human geography. He also establishes the main aspects of festival research in geography: cultural, social, economic and time–space analysis, political, historical, general and theoretical. Finally, he suggests future directions in geographical research on festivals. 相似文献
107.
Electromagnetic study of lithospheric structure in the marginal zone of East European Craton in NW Poland 总被引:1,自引:0,他引:1
Waldemar Jóźwiak 《Acta Geophysica》2013,61(5):1101-1129
The marginal zone of the East European Platform, an area of key importance for our understanding of the geotectonic history of Europe, has been a challenge for geophysicists for many years. The basic research method is seismic survey, but many important data on physical properties and structure of the lithosphere may also be provided by the electromagnetic methods. In this paper, results of deep basement study by electromagnetic methods performed in Poland since the mid-1960s are presented. Over this time, several hundred long-period soundings have been executed providing an assessment of the electric conductivity distribution in the crust and upper mantle. Numerous 1D, 2D, and pseudo-3D electric conductivity models were constructed, and a new interpretation method based on Horizontal Magnetic Tensor analysis has been applied recently. The results show that the contact zone is of lithospheric discontinuity character and there are distinct differences in geoelectric structures between the Precambrian Platform, transitional zone (TESZ), and the Paleozoic Platform. The wide-spread conducting complexes in the crust with integral conductivity values reaching 10 000 S at 20–30 km depths are most spectacular. They are most likely consequences of geological processes related to Caledonian and Variscan orogenesis. The upper mantle conductivity is also variable, the thickness of high-resistive lithospheric plates ranging from 120–140 km under the Paleozoic Platform to 220–240 km under the East European Platform. 相似文献
108.
High-frequency quasi-periodic variations (HF QPOs) in the X-ray light curves of black hole X-ray novae can be understood as
oscillations of the accretion disk in a nonlinear 3:2 resonance. An m = 0 vertical oscillation near a black hole modulates the X-ray emission through gravitational lensing (light-bending) at
the source. Certain oscillations of the accretion disk will also modulate the mass accretion rate, and in neutron-star systems
this would lead to nearly periodic variations in brightness of the luminous boundary layer on the stellar surface – the amplitude
of the neutron-star HF QPOs would be thus increased relative to the black hole systems.
The “kHz QPOs” in black holes are in the hecto-Hz range. 相似文献
109.
Karol Przeździecki Jarosław Zawadzki Zygmunt Miatkowski 《Environmental Earth Sciences》2018,77(17):623
Anthropogenic activities, especially resulting in changes in the water conditions, usually disturb biological and agricultural functions of grasslands, leading to their degradation, often on large areas. Remote sensing observations of such changes in grassland ecosystems evoke a great interest, but they are still a difficult task, especially when performed on industrial and mining areas. This paper presents a new effective method of remote sensing of grassland moisture conditions based on temperature–vegetation dryness index (TVDI) calculated from free Landsat imagery, and employing the TVDI spatial variability estimated from a semivariance analysis. The practical applicability of the method is demonstrated on the example of monitoring of the extensive neighborhood of lignite open-cast mine within a period of a few years. Besides, the developed method was validated at the studied area, using in situ information. Thus, we demonstrated that TVDI may serve as an effective indicator of grassland moisture conditions, even in problematic areas. 相似文献
110.
Tomasz Rychliński Andrzej Gaździcki Alfred Uchman 《Swiss Journal of Geoscience》2018,111(1-2):305-315
The green alga Palaeodasycladus was recognized in Lower Jurassic shallow-marine high-energy calcarenites of the Cho? Nappe (Hronicum Domain) in the Tatra Mts in Poland. This occurrence indicates the most Northern record of Palaeodasycladus as it is known mostly from the southern part of the Western Tethys. The stratigraphic range of Palaeodasycladus (Norian, Sinemurian–Pliensbachian) and the upper Pliensbachian age of the overlying calcarenites (previous data on the basis of brachiopods) suggest that the studied part of the section was deposited during the Sinemurian–early Pliensbachian. The previous and current reports on occurrences of Palaeodasycladus allowed determination of a new northern palaeogeographic range of the shallow-marine Mediterranean biota during the Early Jurassic time. 相似文献