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Number of results: 7
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Abstract

Biodegradation of organic matter by sulphate-reducing bacteria (SRB) isolated from soil from military testing ground and petroleum plants were investigated. The isolated microorganisms utilized low molecular weight compounds and participation of SRB in biodegradation of these compounds was similar in marine sediments and in soil (40-55%).
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Authors and Affiliations

Dorota Wolicka
Andrzej Borkowski
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Abstract

In the recent years three-dimensional buildings modelling based on an raw air- borne laser scanning point clouds, became an important issue. A significant step towards 3D modelling is buildings segmentation in laser scanning data. For this purpose an algorithm, based on the multi-resolution analysis in wavelet domain, is proposed in the paper. The proposed method concentrates only on buildings, which have to be segmented. All other objects and terrain surface have to be removed. The algorithm works on gridded data. The wavelet-based segmentation proceeds in the following main steps: wavelet decomposition up to appropriately chosen level, thresholding on the chosen and adjacent levels, removal of all coefficients in the so-called influence pyramid and wavelet reconstruction. If buildings on several scaling spaces have to be segmented, the procedure should be applied iteratively. The wavelet approach makes the procedure very fast. However, the limitation of the proposed procedure is its scale-based distinction between objects to be segmented and the rest.
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Authors and Affiliations

Wolfgang Keller
Andrzej Borkowski
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Abstract

The paper presents a summary of research activities concerning theoretical geodesy performed in Poland in the period of 2011–2014. It contains the results of research on new methods of the parameter estimation, a study on robustness properties of the M-estimation, control network and deformation analysis, and geodetic time series analysis. The main achievements in the geodetic parameter estimation involve a new model of the M-estimation with probabilistic models of geodetic observations, a new Shift-M split estimation, which allows to estimate a vector of parameter differences and the Shift- M split (+) that is a generalisation of Shift- M split estimation if the design matrix A of a functional model has not a full column rank. The new algorithms of the coordinates conversion between the Cartesian and geodetic coordinates, both on the rotational and triaxial ellipsoid can be mentioned as a highlights of the research of the last four years. New parameter estimation models developed have been adopted and successfully applied to the control network and deformation analysis. New algorithms based on the wavelet, Fourier and Hilbert transforms were applied to find time-frequency characteristics of geodetic and geophysical time series as well as time-frequency relations between them. Statistical properties of these time series are also presented using different statistical tests as well as 2 nd , 3 rd and 4 th moments about the mean. The new forecasts methods are presented which enable prediction of the considered time series in different frequency bands.
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Authors and Affiliations

Andrzej Borkowski
Wiesław Kosek
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Abstract

The GRACE-based model GGM02S is a global gravity model expressed in spherical harmonics. As the model is a global solution, a certain smoothing of the available gravity field information is unavoidable. For regional geoid determination the irregularities of residual gravity field should be included. The paper presents the global GRACE gravity field solution, regionally improved by adding a residual field, which is represented by radial base functions. The GRACE observations over the territory of Poland are analysed and a regionally improved GRACE geoid from this data is derived. This improved regional geoid is compared with the Polish quasigeoid and differences between the global and regionally improved GRACE GGM02S solutions are discussed. The study shows that the error of the official GRACE GGM02s solution was reduced by 50% due 10 regional refinement.
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Authors and Affiliations

Antoni Markus
Andrzej Borkowski
Wolfgang Keller
Magdalena Owczarek
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Abstract

The summary of research activities concerning general theory and methodology performed in Poland in the period of 2015–2018 is presented as a national report for the 27th IUGG (International Union of Geodesy and Geophysics) General Assembly. It contains the results of research on new or improved methods and variants of robust parameter estimation and their application, especially to control network analysis. Reliability analysis of the observation system and an integrated adjustment approach are also given. The identifiability (ID) index as a new measure for minimal detectable bias (MDB) in the observation system of a network, has been introduced. A new method of covariance function parameter estimation in the least squares collocation has been developed. The robustified version of the Shift-Msplit estimation, termed as Shift-M*split estimation, which enables estimation of parameter differences (robustly), without the need of prior estimation of the parameters, has been introduced. Results on the analysis of geodetic time series, particularly Earth orientation parameter time series, geocenter time series, permanent station coordinates and sea level variation time series are also provided in this review paper. The entire bibliography of related works is provided in the references.

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Authors and Affiliations

Andrzej Borkowski
Wiesław Kosek
Marcin Ligas

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