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1

Zastosowanie krigingu map RSSI do lokalizacji wewnątrzbudynkowej metodą odcisków palców wspomaganej filtracją cząsteczkową

Kawecki Robert, Hausman Sławomir, Korbel Piotr

Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

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2023

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nr 4

240--243

PL

W artykule zaprezentowano możliwość wykorzystania alternatywnej metody interpolacji rozkładów propagacji sygnału radiowego – kriging. Prezentowane referencyjne mapy RSSI są wykorzystywane jako zbiory danych do systemu lokalizacji w budynkach. System wykorzystuje metodę odcisków palców wspomaganą algorytmem filtracji cząsteczkowej. W ramach prezentowanych prac badawczych zweryfikowano, że możliwe jest efektywne wykorzystanie metody kriging do interpolacji danych pomiarowych RSSI i uzyskanie mniejszego błędu średniego i medianowego niż wykorzystanie danych pomiarowych lub rozkładów RSSI wygenerowanych z wykorzystaniem interpolacji liniowej.

EN

The article presents the possibility of using an alternative method of interpolation of radio signal propagation distribution sets – kriging. The presented reference RSSI distributions are used as data sets for the location system in buildings. The localization system uses the fingerprint method supported by a molecular filtration algorithm. As part of the presented research, it was verified that it is possible to effectively use the kriging method to interpolate RSSI measurement data and obtain a smaller average and median error than using measurement data or RSSI distributions generated using linear interpolation.

2

The overview of trends and challenges in mobile biometrics

Wojciechowska A., Choraś M., Kozik R.

Journal of Applied Mathematics and Computational Mechanics

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2017

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Vol. 16, nr 2

173--185

EN

Currently, various biometric modalities are used to perform human identification or user verification. Although the research results are promising, the constant development of biometric systems is needed. Recently, biometric systems are also implemented for mobile devices, services and applications. In this article, the review of current trends in mobile biometrics is discussed. The paper also describes the most challenging aspects like aging, template protection or wide users’ acceptance. Finally, palmprints are described as the trait that may give promising results and could be implemented widely in mobile biometrics.

3

Determination of the directional field of fingerprints papillary lines in automated biometric identification systems

Selianinau M., Ismailau R.

Prace Naukowe Akademii im. Jana Długosza w Częstochowie. Technika, Informatyka, Inżynieria Bezpieczeństwa

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2015

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T. 3

221-229

PL

W pracy przedstawiono nową metodę opartą na analizie cech gradientu, aby wyznaczyć pole kierunków odcisków palców. Metoda ta oblicza wygładzony obraz orientacji linii papilarnych. Jej głównym elementem jest analiza lokalnego histogramu kierunków, biorąc pod uwagę moduł gradientu w kwadratowym obszarze, którego rozmiar jest współmierny ze średnią odległością między grzbietami na obrazie odcisku palca. Weryfikacja doświadczalna tej metody dla odcisków palców różnej jakości wykazała, że uzyskuje się lepsze wyniki w porównaniu ze znanymi metodami opartymi na analizie poziomów szarości wzdłuż wybranych kierunków.

EN

This paper presents a new method, based on the gradient characteristics analysis, to estimate the directional field of fingerprints. The method computes the smoothed orientation image of papillary lines. Its main component consists in n the analysis of the local histogram of the directions taking into account the gradient module in a square neighborhood which size is commensurable with the average inter--ridges distance on the fingerprint image. Experimental verification of this method for f fingerprints of different quality showed that it yields better results in comparison with the known methods based on the analysis of gray-scale levels along the selected directions.

4

Enzymatic fingerprints used for comparison of physiological diversity of microbial communities in clear-water and humic lakes

Siuda W., Jasser I., Kiersztyn B.

Polish Journal of Ecology

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2013

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Vol. 61, nr 4

715--728

EN

Extracellular enzymes occurring in aquatic environment are heterogeneous in respect to their origin and function, place, where they are located and their activity. They can be divided into mainly ‘bacterial-origin’ enzymes produced by heterotrophic organisms in order to obtain organic carbon, and mostly ‘phytoplankton-bacterial-origin’ enzymes, which are produced by autotrophic and heterotrophic organisms, and are responsible mainly for obtaining inorganic compounds. Enzymes activity provides information about microorganisms present in given environment and about their physiological state. We hypothesize that the patterns (‘fingerprints’) calculated on the basis of activity of several enzymes both mainly ‘bacterial-origin’ and mainly ‘phytoplankton-bacterial-origin’ may be used to characterise lake ecosystems in terms of the physiological structure of aquatic microorganisms present in these lakes. For the study we selected four lakes from Mazurian Lakes District in north-eastern Poland. Three of them were clear-water (lakes: Kuc, Mikołajskie, Tałtowisko) and ranged from oligotrophy to eutrophy, the fourth (Lake Smolak Duży) was slightly acidic (pH 5.2), highly productive and polyhumic. Activity of phosphatase (PA), L-leucine-aminopeptidase (AMP), β-glucosidase (B-Glu), esterase (EST), glucosaminidase (Glu-ami), glucuronidase (Glu-uro) and cellobiohydrolase (Cellob) were measured fluorometrically. The results were normalised and analysis of agglomerative clustering was performed to create an enzyme activity patterns characteristic for lakes. We found out that the enzymatic pattern reflected trophic differences between studied lakes. The patterns (‘fingerprints’) of enzymes were similar for three clear-water lakes, with urease (U–ase), AMP and EST dominating the overall enzymatic activity, but differed substantially for polyhumic lake, in which considerably high PA and saccharolytic enzyme activities were observed. We conclude that the analysis of enzymatic ‘fingerprints’ can be a useful tool to characterise lakes with respect to their trophic status and physiological diversity of microbial assemblages associated with each particular lake.

5

A review on fingerprint orientation estimation methods

Więcław Ł.

Journal of Medical Informatics & Technologies

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2012

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Vol. 21

95--102

EN

As a global feature of fingerprint, orientation field plays important roles in most of image preprocessing methodsused in automatic fingerprint identification system (AFIS). Many algorithms have been proposed for orientation field estimation. This paper reviews the advantages and disadvantages of existing fingerprint orientation estimation methods. Issues on possible directions of further development have been presented.