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1

Analysis of the possibility of using archival maps as a source of elevation data

Cichociński Piotr

GIS Odyssey Journal

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2021

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Vol. 1, no. 1

177--188

EN

One of the most popular sources of elevation data covering the most of the Earth's surface with spatial resolution of up to 30 m (1 angular second to be exact) is the SRTM model. This terrain model has two main disadvantages: it covers the area of the Earth between the parallels 54°S and 60°N only, and in some mountainous and desert areas there are gaps (voids) in the data. Additionally, it may not be suitable for more detailed visualization and analysis due to their limited accuracy. Therefore, the paper attempts to find an alternative source of elevation data. One of them may be archival maps, on which the terrain is presented by means of contours. By vectorization of such lines and adding respective attributes they can serve as a base for building digital terrain models. Examples of such maps are maps created in the period before World War II by Polish Military Geographical Institute (WIG). Although newer topographic maps or even more accurate spatial databases exist, it is assumed that as official materials WIG maps were not covered by copyright, so they are in public domain, just like SRTM. Conducted research and literature studies have shown that the issue of using contours extracted from archival topographic maps is not unambiguous. The lack of reproducibility in the results obtained does not allow making clear recommendations on the feasibility of using archival maps. Using a contour drawing as the sole source of elevation data, without any control, should be considered risky. On the other hand, it seems possible to use them as supplementary and perhaps refining material, but only in places where consistency with other data can be observed.

2

Interaction between turbidity currents and a contour current – a rare example from the Ordovician of Shaanxi province, China

Li Hua, van Loon A. J. (Tom), He Youbin

Geologos

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2019

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Vol. 25, No. 1

15--30

EN

The silty top parts of graded turbidites of the Late Ordovician Pingliang Formation, which accumulated along the southern margin of the Ordos Basin (central China), have been reworked by contour currents. The reworking of the turbidites can be proven on the basis of paleocurrent directions in individual layers: the ripple-cross-bedded sandy divisions of some turbidites show transport directions consistently into the downslope direction (consistent with the direction of other gravity flows), but in the upper, silty fine-grained division they show another direction, viz. alongslope (consistent with the direction that a contour current must have taken at the same time). Both directions are roughly perpendicular to each other. Moreover, the sediment of the reworked turbidites is better sorted and has better rounded grains than the non-reworked turbidites. Although such type of reworking is well known from modern deep-sea environments, this has rarely been found before in ancient deep-sea deposits. The reworking could take place because the upper divisions of the turbidites involved are silty and consequently relatively easily erodible, while the contour current had locally a relatively high velocity – and consequently a relatively large erosional capability – because of confinement within a relatively narrow trough.

3

Matematyczne modelowanie kształtu podstawowych części morfologicznych cebuli cukrowej (Allium cepa L.)

Mieszkalski L.

Postępy Techniki Przetwórstwa Spożywczego

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2016

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Nr 1

40--46

PL

W artykule zaproponowano metodę matematycznego modelowania kształtu główki cebuli cukrowej holenderskiej odmiany Alonso (Allium cepa L.). Do modelowania wybrano dużą cebulę z obciętym szczypiorem, o długości wynoszącej 149 mm, szerokości 125,2 mm i grubości 124,5 mm.W modelu matematycznym zastosowano opis konturów za pomocą krzywych Béziera, które obracano względem osi symetrii cebuli. Dla główki cebuli opracowano matematyczny opis konturów mięsistych łusek i piętki. Zapisane współrzędne węzłów siatki powierzchni modelu główki cebuli będą podstawą projektowania zespołów roboczych urządzeń stosowanych w przetwórstwie cebuli.

EN

The article proposes a method of mathematical modeling of the shape of the head of the dutch varieties of onion sugar Alonso (Allium cepaL.). To the modeling selected a large onions length of with clipped stems of 149 mm, a width of 125.2 mm and a thickness of 124.5 mm. The mathematical model uses a description of contours by means of Bezier curves that rotates with respect to the axis of symmetry of the onion. For the onion bulbs developed a mathematical description of the contours of fleshy scales and heel. Saved grid nodes coordinates surface of the model of onion bulbs will be the basis of design of teams equipment used in the processing of onion.

4

Development of a Procedure for Camouflage Pattern Design

Friškovec M., Gabrijelčič H.

Fibres & Textiles in Eastern Europe

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2010

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Vol. 18, no. 4 (81)

68--76

EN

Today, camouflage uniforms are an indispensable part of military equipment and serve not only as a means of disguising an object in a certain environment but also as a national symbol. Since battlefields and areas of international conflicts also take place in urban environments, the need to design urban camouflage is all the greater. The purpose of the research was to develop a procedure to create a set of camouflage patterns for the urban environment. The experimental part included the selection and processing of digital images of representative urban environments. Image processing simplified the digital photos by changing them into surface elements and contours, which helped us to extract representative shapes and sequences. Afterwards three methods for pattern design including the random and planned composition of shapes and sequences were developed and analysed. The procedures for pattern design included compositional and pictorial analyses of simplified digital images, principles of fractal sequences, a theory of the psychophysical comprehension of shapes and sequences, and knowledge about the visual and optical effects of shapes and repeats. The result of the research was the definition of an optimal procedure for digital camouflage pattern design, which was also confirmed by the Slovenian Ministry of Defence and Armed Forces.

PL

Współcześnie odzież maskująca stanowi niezbędne wyposażenie wojskowe i służy nie tylko dla kamuflażu obiektu w danym otoczeniu ale również jako cecha rozróżniająca formacje wojskowe. Ponieważ obecnie międzynarodowe konflikty mają często miejsce w środowiskach miejskich wzrasta zapotrzebowanie na kamuflaż uwzględniający tego typu krajobraz. Celem badań było opracowanie metody uzyskiwania odpowiednich wzorów kamuflażu. Korzystając z fotografii opracowywano cyfrowe obrazy graficzne przetwarzając je w zróżnicowane struktury, które następnie analizowano. W czasie analizy wykorzystywano teorię fraktali i analizy psychologiczne. Celem pracy badawczej było uzyskanie optymalnego kamuflażu dla działania określonych jednostek operacyjnych.

5

Porównanie wybranych transformatowych metod kompresji konturów

Baran R.

Zeszyty Naukowe Politechniki Świętokrzyskiej. Elektryka

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2005

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Z. 42

23-37

PL

W artykule przedstawiono wyniki porównania własności kompresyjnych wybranych transformatowych metod kompresji konturów: metody strefowej i progowej. Badania przeprowadzono z użyciem licznej grupy konturów testowych. W analizie wykorzystano transformaty DCT, Walsha, Haara oraz przekształcenia odcinkowo-liniowe PWL, HPL i PHL. Badane właściwości oceniano na podstawie stopnia kompresji, tj. stosunku liczby bitów wymaganych do reprezentacji sygnału przed kompresją do liczby bitów reprezentacji po kompresji. W związku z powyższym dla każdego z analizowanych schematów kompresji zaproponowano struktury nadajnika i odbiornika oraz formaty transmitowanych danych.

EN

The compression abilities of selected transform compression methods - threshold and zonal compression schemes, were analysed. Results of comparison were presented in the paper. Many of previously prepared contours were tested during the experiments. The DCT, Walsh, Haar and piecewise-linear transforms - PWL, HPL and PHL, were used for the analysis. Compared abilities were measured using the compression degree - ratio of total number of bits required for contour representation before the compression to number of bits required after the compression. Therefore, the transmitter and receiver parts were designed separately for each of analysed schemes. Formats of transmitted information were also proposed separately.