8 research outputs found
Wykorzystanie metod GIS do wyznaczania działów wodnych zlewni zurbanizowanych na przykładzie miasta Kielce
W pracy przedstawiono analizę powierzchni i zasięgu zlewni rzeki Silnicy oraz jej sześciu zlewni cząstkowych wyznaczonych metodami GIS w trzech wariantach z użyciem NMT z projektu ISOK o rozdzielczości 1 m, bazy danych obiektów topografi cznych (BDOT) w skali 1 : 10 000 oraz geodezyjnej ewidencji sieci uzbrojenia terenu (GESUT). Przeanalizowano także różnice zasięgu zlewni Silnicy wyznaczonego na podstawie mapy topografi cznej w skali 1 : 10 000, a także pozyskanego z mapy podziału hydrografi cznego Polski (MPHP) 1 : 10 000. W każdym z wariantów przeprowadzonego modelowania zmianom ulegał przebieg granic badanych zlewni, co spowodowało zarówno zmiany ich areału, jak i zasięgu przestrzennego. Najlepsze rezultaty dało wykorzystanie procedur wyznaczania granic zlewni w GIS z użyciem NMT oraz skorygowanych baz BDOT i GESUT. W tym przypadku zasięgi zlewni pokrywały się z rzeczywistymi zasięgami odwodnienia. Tradycyjne metody wyznaczania działów wodnych z wykorzystaniem mapy topograficznej oraz istniejące źródła danych w postaci MPHP w skali 1 : 10 000 były mało dokładne w stosunku do całej zlewni Silnicy i nieprzydatne do wyznaczenia małych zlewni cząstkowych w centrum Kielc
Use of Quantum GIS and SAGA GIS software to build digital elevation model of Grajcarek catchment
W artykule przedstawiono możliwości opracowania cyfrowego modelu wysokościowego
(CMW) w formie rastra o rozdzielczości przestrzennej 5 m dla zlewni potoku
Grajcarek, której powierzchnia wynosi 85 km2
. CMW stworzono na podstawie digitalizacji
poziomic z mapy topograficznej w skali 1:10 000, z użyciem oprogramowania
typu Open-Source GIS – Quantum GIS i SAGA GIS. Opisano procedurę tworzenia
modelu, rozpoczynając od wektoryzacji treści mapy topograficznej, przez wybór metody
interpolacji, kończąc na preprocessingu, prowadzącym do uzyskania poprawności
hydrologicznej modelu. Szczególną uwagę zwrócono na niedoskonałości tworzonego
CMW, wynikające z zastosowania różnych metod interpolacji. Pomimo iż budowa
CMW zgodnie z opisaną procedurą jest bardzo czasochłonna, to stanowi często jedyną
możliwość pozyskania dokładnego modelu wysokościowego małych zlewni lub innych
jednostek przestrzennych, który umożliwiałby przeprowadzanie szczegółowych analiz
hydrologicznych, geomorfologicznych lub innych interpretacji.In this paper use of 1:10 000 scale topographic maps and open-source GIS software
to build Digital Elevation Model (DEM) with 5-meters resolution was analysed. DEM
was built from contour lines vectorised in Quantum GIS using five different
interpolation methods available in SAGA GIS: Ordinary Kriging, Ordinary Kriging with
Block Kriging, Thin Plate Spline (Local), Thin Plate Spline (TIN), Multilevel B-Spline
Interpolation. Special attention was given to the accuracy of DEM's built with those
methods. DEM's were analyzed by crossvalidation of their surface with elevation points
vectorised from topographic maps, which were not used in DEM interpolations.
Correctness of generated drainage network was also investigated. Although construction
of DEM in presented way is very time-consuming, it is often the only way to build highresolution
DEM of small catchments or other spatial units, which could be used in largescale
hydrological or geomorphological modelin
Morphological and soil determinants of forest cover changes in Świętokrzyski National Park and its buffer zone in the last 200 years
The research described in the paper utilized GIS methods and comparative cartography in order to analyze changes in forest cover in the period 1800–2011 in the Świętokrzyski National Park (76.26 km²) and its buffer zone (207.86 km²). The research was done for predefined elevation intervals, slope gradients, and genetic soil types. Source materials included historical maps as well as a digital elevation model. Changes in forest cover were noted in spatial and temporal terms and were usually linked to morphology and soil type. While the 19th century was characterized by intense deforestation, this process reversed starting in the early 20th century. Nevertheless, forest cover in the study area has still not returned to its state from 1800
Morphological and soil determinants of forest cover changes in Świętokrzyski National Park and its buffer zone in the last 200 years
The research described in the paper utilized GIS methods and comparative cartography in order to analyze changes in forest cover in the period 1800–2011 in the Świętokrzyski National Park (76.26 km²) and its buffer zone (207.86 km²). The research was done for predefined elevation intervals, slope gradients, and genetic soil types. Source materials included historical maps as well as a digital elevation model. Changes in forest cover were noted in spatial and temporal terms and were usually linked to morphology and soil type. While the 19th century was characterized by intense deforestation, this process reversed starting in the early 20th century. Nevertheless, forest cover in the study area has still not returned to its state from 1800
Changes in the topography of Krakow city centre, Poland, during the last millennium
The aim of the paper is to reconstruct differences between the paleotopography and contemporary topography of the historic centre of Krakow city, Poland, during the last millennium. The paleotopography was reconstructed using published contour-line maps based on archaeological and geoengineering investigations and showing the roof of in situ fossil soil. The preliminary contour-line map represented a digital elevation model (DEM) base map. A DEM from aerial laser scanning (ALS DEM) shows the contemporary topography of Krakow city centre. The application of selected morphometric indices makes it possible to quantitatively describe changes in the spatial dimension with regard to altitude, relative heights, slope, and aspect classes. The analysis of the changes in the values of the elements of topography studied shows that, at the scale of the whole study area, a trend to flattening occurs, however this trend is locally balanced or overridden by an increase of surface unevenness
Morphological and Soil Determinants of Forest Cover Changes in Świętokrzyski National Park and Its Buffer Zone in the last 200 Years
The research described in the paper utilized GIS methods and comparative cartography in order to analyze changes in forest cover in the period 1800-2011 in the Świętokrzyski National Park (76.26 km²) and its buffer zone (207.86 km²). The research was done for predefined elevation intervals, slope gradients, and genetic soil types. Source materials included historical maps as well as a digital elevation model. Changes in forest cover were noted in spatial and temporal terms and were usually linked to morphology and soil type. While the 19th century was characterized by intense deforestation, this process reversed starting in the early 20th century. Nevertheless, forest cover in the study area has still not returned to its state from 1800
The Use of Computed Tomography in the Study of Microstructure of Molded Pieces Made of Poly(3-hydroxybutyric-co-3-hydroxyvaleric acid) (PHBV) Biocomposites with Natural Fiber
In order to determine the structure homogeneity of biocomposites filled with fibers, as well as the evaluation of fibers’ arrangement and their orientation on the sample cross-section at varied injection rates, a study was conducted using computed tomography (CT). The main advantage of this test is the fact that in order to assess the microstructure on cross-sections, the samples do not have to be processed mechanically, which allows for presenting the actual image of the microstructure. The paper presents the issues of such tests for the biocomposite of poly (3-hydroxybutyric-co-3-hydroxyvaleric acid) (PHBV)-hemp fibers. It should be emphasized that CT scanning of PHBV-hemp fiber biocomposites is quite difficult to perform due to the similar density of the fibers and the polymer matrix. Due to the high difficulty of distinguishing fibers against the background of the polymer matrix during CT examination, a biocomposite containing 15% hemp fibers was analyzed. The samples for testing were manufactured using the injection molding process at variable injection rates, i.e., 10, 35 and 70 cm3/s. The images obtained by computed tomography show the distribution of hemp fibers and their clusters in the PHBV matrix and the degree of porosity on the sample cross-section. There were significant microstructural differences for the samples injected at the highest injection rates, including, among others, the occurrence of a smaller number of fibers and pores on the surface layer of the molded piece. The phenomenon observed was verified by testing chosen mechanical properties, shrinkage and water absorption of the samples. Some properties improved with an increasing injection rate, while others deteriorated and vice versa. An analysis of biocomposites’ microstructures using computed tomography provides a wide range of possibilities for future research, including an assessment of the structure of the molded parts. These tests may allow one, for example, to detect the cause of molded piece properties decreasing in a specific area as a result of a high degree of fiber disorientation, as well as the defects resulting from high porosity of the material. Such analyses can be particularly useful for producers that deal with the injection molding of pieces molded with specific properties