Wyniki wyszukiwania - BazTech

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Analiza danych pomiarowych echosondy wielowiązkowej Simrad EM3000

Maleika W., Pałczyński M., Frejlichowski D., Stateczny A.

Metody Informatyki Stosowanej

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2010

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nr 4 (24)

55-64

EN

Errors of depth measurement are one of the most important problems in area of bathymetric data processing. The authors examined a data set aquired with the multibeam eehosounder Sim rad EM3000 in order to estimate the character of errors. For every measurement line formed by the survey points, the theoretical model of this fragment of bottom was defined using approximation. The differenees between this model and the survey points were treated as the measurement errors, which appeared to have a random distribution. The correlation of error value and angle between the beam and the vertical line could be observed. 99.7 % of er- ror values was smaller than 7 cm for depths between 10 and 20 m, while mean value of errors was approx. 3 cm.

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Metody przyrostowe w przetwarzaniu danych batymetrycznych - analiza błędów przetwarzania dla zaproponowanych modeli matematycznych

Ogrodniczak J.

Roczniki Geomatyki

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2007

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T. 5, z. 3

105-112

EN

In the papers [1, 2] mathematical models using incremental methods in processing of information about the course of variability in the shape of sea bed along the measurement profile were proposed. These models were implemented in author.s application and served simulation tests. The results of the tests were used for comparisons and for assessment of possibilities to use them in the case of various shapes of the seabed. 1. Janusz Ogrodniczak, "Metody przyrostowe w przetwarzaniu danych batymetrycznych-kryteria oceny dokładności dopasowania przebiegu aproksymującego do sygnału wejściowego., (Incremental methods in the bathymetric data processing . accuracy criteria for the approximation of input signal) Roczniki Geomatyki (Annals of Geomatics) 2006, Vol. IV, Number 3, Warszawa. 2. Janusz Ogrodniczak, "Incremental Methods in Bathymetric Data Processing - Bathymetric Data Quantisation", Advances in Transport Systems Telematics, Section III, Chapter 10, Katowice, 2006.

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Metody przyrostowe w przetwarzaniu danych batymetrycznych – kryteria oceny dokładności dopasowania przebiegu aproksymującego do sygnału wejściowego

Ogrodniczak J.

Roczniki Geomatyki

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2006

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T. 4, z. 3

165-170

EN

The possibilities to use delta modulation based incremental methods in the bathymetric data processing are described in this paper. The bathymetric data is a geo-referenced depth data. The depth measurement is made in fixed time intervals so it could be assumed that it is a kind of a signal. Contemporary survey systems provide users with huge amount of data. In the paper it is decided to incorporate the delta modulation into the bathymetric data processing as a method of reducing the amount of the bathymetric data to be transmitted or stored. The delta modulation is a technique taken from signal processing. It is usually used to process electric signals so comparison of voltage levels at the sampling time is the criterion. When considering series of the bathymetric data as a signal, some of the ideas from terrain modeling were adapted to the delta modulation based system. Hence, additional two criteria are taken: a difference between the slope of approximation and the slope of the sea bottom shape and the distance between curves represented by the approximation and the sea bottom shape.