Landslides are a phenomenon commonly found on the slopes of valleys and water bodies, as well as areas of rivers, embankments and slopes of excavations. Sudden landslides in these areas can be monitored using photogrammetric technique. The aim of this paper is to present the possibility of close-range photogrammetry (CRP) and terrestrial laser scanning (TLS) to conduct monitoring of surface changes that have taken place due to geodynamic processes. The studies were conducted on a 22-m section of the Vistula River scarp in P³ock. Terrestrial images, taken three times every six months, as well as terrestrial laser scanner measurements were used to determine the morphological changes occurring on a portion of the Vistula River scarp in Płock in one year. Based on the measurements, a thick cloud of points and a three-dimensional terrain model of the area of interest were obtained each time. Next, a comparative analysis of models taken at different times was carried out. Results of measurements allowed demonstrating the overall stability of the slope, i.e. the lack of morphological changes in the analysed period, with minor changes in some of its regions (loss of soil mass in the northern part and the growth in the southern part of the test area). The study shows that, in morphologically difficult areas, CRPcan provide information about the direction and magnitude of deformation, when changes are formed rapidly and contribute to large (at least several-decimetre) geodynamic changes.
The mining exploitation of hard coal in Upper Silesia has been conducted since XIX century and continues to the present days. Different methods of monitoring subsidence of the earth surface were applied in this area, startingfrom analysis of topographic maps compiled in different period of time, precise levelling and GPS measurements. Nowadays satellite interferometry seems to be use- ful and effective tool for these purposes. PS data from ERS and ENVISAT satellites very well illustrate subsidence occurring in the active mining areas where subsidence does not exceed- 40 mm /yr. These data correspond very well with subsidencepredictive models prepared by mining companies. However, the Upper Silesian Coal Basin (USCB) mining area subsides even up to 600 mm/yr (locally even more). Therefore, it is necessary to apply a different methodology. One of the solutions to this problem could be differential interferograms obtainedfrom L-band SAR images. Combination of C-Band (ERS, Envisat) andL-band (ALOS) shows excellent results. C-band SAR satellites are useful for detecting smaller displacements; in contrary L-band satellites are able to monitor surface defor- mations in range of several decimetres, being possible to detect progress of mining front.
Celem niniejszego referatu jest porównanie dokładności odtworzenia kształtu elementu łopaty wirnika nośnego śmigłowca pozyskanego ze zdjęć cyfrowych i skaningu naziemnego. Zdjęcia wykonano aparatem cyfrowym CANON EOS20D. Automatyczne dopasowanie zdjęć (matching), wykonano przy wykorzystaniu programu PhotoModeler Scanner. Do pomiaru badanej powierzchni metodą skaningu naziemnego, wykorzystano precyzyjny skaner optyczny ATOS II firmy GOM, który jest stosowany w pomiarach przemysłowych. Porównanie wygenerowanych modeli 3D, z modelem projektowym obiektu, wykonano w programie NX Siemens, będącym zaawansowanym programem typu CAD/CAM/CAE. Dopasowanie modeli wykonano na całym obiekcie, na wybranych profilach badanej łopaty wirnika. Ocenę dokładności otrzymano na podstawie pomiaru odchyłek na 148 punktach, dla których policzona została wartość średnia. Wymagana dokładność, określona przez specjalistów, odtworzenia kształtu tego rodzaju elementu konstrukcyjnego śmigłowca wynosi 0.1 mm. W prezentowanym eksperymencie otrzymano dla modelu fotogrametrycznego 0.42 mm, dla modelu ze skaningu laserowego 0.22 mm.
EN
The purpose of this paper is to compare the accuracy of shape of an element of the main rotor of a helicopter reconstructed from digital photographs and terrestrial scanner. The purpose of the main rotor is to generate the thrust necessary for the flight (forward, backward, sideward), as well as the moments for stability and control. The construction of such types of objects requires very high precision, since the admissible error of the reproduced part amounts to 0.1 mm. To carry out an analysis of the accuracy, 3D models obtained from different data were generated. A first reference model was created from the design data.. Design data allow to draw profiles of the main rotor and then describe its surface, and it is possible to measure coordinates of any point of the object. A second model was obtained from digital images taken by the Canon EOS 20D camera and with use of two types of coded and uncoded reference points placed on the object. Automatic image matching was executed in the PhotoModeler Scanner software. The third model was reconstructed on the basis of data from terrestrial laser scanning, where the industrial precise ATOS II scanner from the GOM company was used. In addition, special target points for automatic scan matching on this object were located. A comparison of these two generated 3D models with the reference model was carried out in the NX program, which is an advanced CAD/CAM/CAE software. Based on the analysis, both evaluation of the accuracy of the generated models and the time consumption and economic aspects were compared.
W wyniku fragmentacji i zanikania ekosystemów mokradłowych, spowodowanego nieodpowiednim użytkowaniem, powierzchnia torfowisk w Europie Zachodniej zmniejszyła się w XX wieku o ponad 90%, a w Europie Centralnej i Wschodniej - szacunkowo o 50--90%. Zmeliorowane torfowiska określa się jako obszary zdegradowane przyrodniczo z powodu silnego odwodnienia, dużych wahań poziomu wód gruntowych oraz znacznego stopnia mineralizacji torfu. W celu przywrócenia i ochrony różnorodności biologicznej torfowisk, w wielu krajach są prowadzone projekty ochrony czynnej (nature management) oraz renaturyzacji (restoration) takich ekosystemów. W Polsce eksperymentalne prace renaturyzacyjne metodą usuwania zmurszałej wierzchnicy torfowiska na głębokość 20 i 40 cm są prowadzone na terenie Bagna Całowanie. Celem badań było sprawdzenie, czy w glebie znajdują się zdolne do kiełkowania nasiona roślin torfowiskowych (lub roślin łąk podmokłych), które umożliwiłyby spontaniczne odtworzenie się tej roślinności. Przeprowadzono analizy banku nasion metodą wschodu siewek. Na powierzchni, z której usunięto mursz, znaleziono niewiele zdolnych do kiełkowania nasion. Glebowy bank nasion był zdominowany przez kilka gatunków roślin ruderalnych (60% banku nasion) lub gatunków o szerokiej amplitudzie ekologicznej. Stwierdzono, że na badanym terenie istniejący glebowy bank nasion nie umożliwia spontanicznej regeneracji roślinności torfowiskowej.
EN
Due to fragmentation and disappearance of wetland ecosystems after their transformation into productive agricultural land, the surface of peatlands in Western Europe in the 20th century declined by over 90% and in Central and Eastern Europe by 50 to 90%. Severely drained peatlands suffer form desiccation, large fluctuations of groundwater levels and advanced peat mineralization. Still, some of those areas preserved natural values and fen ecosystems or semi-natural fen meadows of high biodiversity could be restored there. In many western countries, nature management or nature restoration actions are carried out in order to conserve and improve the biodiversity of peatland areas. In Poland such actions are applied in Całowanie Fen, where the top soil removal method is tested (removal of 20 and 40 cm of top soil). This technique allows local improvement of moisture conditions, nutrient impoverishment and removal of the ruderal and nitrophilous vegetation together with its seed bank. The objective of this study was to check if any viable seeds of the typical plant species of fens or fen meadows are still present in the soil seed bank. If present, the soil seed bank would contribute to the re-establishment of target vegetation on the restoration plots. Lack of persistent seed bank and limited natural dispersal of the target plant species have been identified as main limitations of meadow restoration in Western Europe. The soil seed bank analyses were done with the seed germination method. In the process of degradation, the target species seed bank has been depleted. In order to assess the extent of this depletion, the soil seed bank of the degraded fen (Całowanie Fen) and well-preserved fen (fen near village Lipsk) were compared. On restored plots after top soil removal few viable seeds have been found and the soil seed bank was dominated by a few ruderal (60%) or common species that tolerate wide range of environmental conditions (e.g. Juncus articulatus). We concluded that in the studied site, the restoration of fen meadow community can not rely on spontaneous recovery of vegetation from the soil seed bank.
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.