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Node Localization based on Anchor Placement using Fuzzy C-Means in a Wireless Sensor Network

Irid Sidi Mohammed Hadj, Hadjila Mourad, Hachemi Mohammed Hicham, Souiki Sihem, Mosteghanemi Reda, Mostefai Chaima

International Journal of Electronics and Telecommunications

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2023

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Vol. 69, No. 1

99--104

EN

Localization is one of the oldest mathematical and technical problems that have been at the forefront of research and development for decades. In a wireless sensor network (WSN), nodes are not able to recognize their position. To solve this problem, studies have been done on algorithms to achieve accurate estimation of nodes in WSNs. In this paper, we present an improvement of a localization algorithm namely Gaussian mixture semi-definite programming (GM-SDP-2). GMSDP is based on the received signal strength (RSS) to achieve a maximum likelihood location estimator. The improvement lies in the placement of anchors through the Fuzzy C-Means clustering method where the cluster centers represent the anchors’ positions. The simulation of the algorithm is done in Matlab and is based on two evaluation metrics, namely normalized root-mean-squared error (RMSE) and cumulative distribution function (CDF). Simulation results show that our improved algorithm achieves better performance compared to those using a predetermined placement of anchors.

2

Blue-emitting polystyrene scintillators for plastic scintillation dosimetry

Kapłon Łukasz, Moskal Gabriel

Bio-Algorithms and Med-Systems

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2021

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Vol. 17, no. 3

191--197

EN

Objectives: Purpose of this research was to find the best blue-emitting fluorescent substance for plastic scintillator used for gamma radiation dosimetry. Scintillator should convert gamma radiation into blue light with high efficiency. Methods: Plastic scintillators with fixed concentration of various fluorescent additives, called wavelength shifters, absorbing ultraviolet light and emitting blue light were manufactured by radical bulk polymerization of styrene. Light output were measured and compared to the light output of commercial plastic scintillator. Results: Performed measurements of charge Compton spectra confirmed usefulness of majority of researched substances as wavelength shifters in plastic scintillators with emission maximum at blue range of visible light. Conclusions: Plastic scintillation dosimeter may be constructed from manufactured polystyrene-based scintillators. Performance of synthesized scintillators is close to commercial polystyrene scintillators.

3

Correlation between weight, error and type of measurements in WLS State estimation of a Real Network

Sabri O., Majdoub M., Cheddadi B., Belfqih A., Boukherouaa J., El Mariami F., Cherkaoui N.

Przegląd Elektrotechniczny

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2017

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R. 93, nr 7

113--116

EN

This paper presents a study of the effect of measurement's weight and error on the accuracy of WLS power system state estimation and the correlation between those two parameters and measurement's type. Different simulation cases are tested on a real Network of 14 bus , part of the electrical transmission network of the Moroccan National Office for Electricity and Potable Water (ONEE).

PL

W artykule zaprezentowano analize wpływu pomiaru wagi i błędu na dokładność metody ważonej najmniejszych kwadratów WLS w systemie energetycznym. Analizowano też korelację tymi dwiema wielkościami.

4

Analiza złożoności efektywnych metod predykcyjnych stosowanych do bezstratnej kompresji obrazów

Ulacha G.

Elektronika : konstrukcje, technologie, zastosowania

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2012

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Vol. 53, nr 4

60-66

PL

W artykule przedstawiono analizę adaptacyjnych metod modelowania predykcyjnego stosowanych do bezstratnej kompresji obrazów. Skupiono się głównie na najefektywniejszych metodach OLS, WLS, AVE-WLS, które dla każdego kodowanego piksela wymagają wyznaczenia macierzy i rozwiązania równania macierzowego. Metody te przeanalizowano pod kątem efektywności i złożoności obliczeniowej, porównując je także do metod o znacznie mniejszej złożoności, takich jak RLS. Omówiono też zaletę kaskadowego łączenia modelowania predykcyjnego z blokiem NLMS.

EN

In the paper, it is presented an analysis of adaptive predictive modelling methods applied to lossless image compression. We focus on the most effective methods: OLS, WLS, AVE-WLS. which for each encoded pixel require constructing a matrix and solving a matrix equation. These methods are analysed with respect to their effectiveness and computational complexity; they are also compared with the methods of considerably lower complexity, such as RLS. The benefits of cascade merging of predictive modelling with the NLMS block are also discussed.