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Zigh E.,National Institute of Telecommunication | Belbachir M.F.,Oran University of Science and Technology - Mohamed Boudiaf | Kadiri M.,University of Mascara
Proceedings of 2015 International Conference on Electrical and Information Technologies, ICEIT 2015 | Year: 2015

Buildings extraction is extremely important for many applications such as natural disasters and crisis management, urban planning and development, or telecommunication, etc. However, extracting automatically buildings from multispectral urban satellite images isn't an easy task because, in one hand, it often needs other technological expensive resources such as Lidar data. In the other hand, the urban environment is becoming more complex and heterogeneous in colours and shapes of its components. From that, we propose in this paper a fuzzy-morphological method applied on urban satellite images delivered alone. It is an hybrid method based on a combination of spectral and spatial pixel information to overcome the limitation of traditional methods. The spectral information is treated using fuzzy logic concept and a spatial one using morphological operations. It can be considered as a thresholding method which achieves the aimed goal according two steps: at first, it does a soft clustering by attributing each pixel to a cluster according to a membership degree, after that, it keeps only interesting regions 'buildings'. Promising buildings extraction results are presented and to show even more the effectiveness of proposed approach, it has been compared to two other thresholding methods. © 2015 IEEE.

Welikow K.,Warsaw University of Technology | Gdula P.,Warsaw University of Technology | Gdula P.,National Institute of Telecommunication | Piramidowicz R.,Warsaw University of Technology
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2011

This work is aimed at implementation and practical verification of effective index approach applicability to microstructured fibers modeling. In particular, the Effective Index Method, both in scalar and fully vectorial form, is presented and discussed with respect of its potential applications for fast and accurate modeling of chromatic dispersion of index guiding microstructured fibers. The developed models, implemented in Matlab environment, allow visualization of the dispersion profiles of index guiding microstructured fibers with hexagonal lattice. To verify accuracy and define the applicability range of developed models, the results of modeling were confronted with the sparse experimental data, reported up to now in scientific papers. The satisfying agreement between numerical and measured results has been obtained, confirming the accuracy of developed model and its applicability to fast analysis and designing of microstructured fibers with dielectric core. © 2011 SPIE.

Prabakaran K.,Anna University | Chandrasekaran R.,Government of Tamilnadu | Mahadevan G.,Anna University | Jaroszewicz Z.,Institute of Applied Optics | And 3 more authors.
Optics Communications | Year: 2013

Focusing properties of the generalized cylindrical vector beam with high numerical aperture lens axicon system is investigated theoretically by vector diffraction theory. Results show that intensity distribution in the focal region can be tailored considerably by appropriately adjusting the polarization angle. Peak-centered, donut and flat top focal shapes with extended focal depth, potentially useful in optical tweezers, material processing and laser printing can be obtained using this technique. © 2012 Elsevier B.V.

Frigieri E.P.,Federal University of Itajuba | Brito T.G.,Federal University of Itajuba | Ynoguti C.A.,National Institute of Telecommunication | Paiva A.P.,Federal University of Itajuba | And 2 more authors.
International Journal of Advanced Manufacturing Technology | Year: 2016

The main objective in machining processes is to produce a high-quality surface finish which, however, can be measured only at the end of the machining cycle. A more preferable method would be to monitor the quality during the cycle, what result a real-time, low-cost, and accurate monitoring method that can dynamically adjust the machining parameters and keep the target surface finish. Motivated by this premise, results of investigation on the relationship between emitted sound signal and surface finish during turning process are reported in this paper. Through experiments with AISI 52100 hardened steel, this work shows that such a correlation does exist presenting strong evidences that Mel-Frequency Cepstral Coefficients, extracted from sound energy, can detect different surface roughness levels, what makes it a promising feature for real-time process quality monitoring methods. © 2016 Springer-Verlag London

Castaneda R.,National University of Colombia | Kolodziejczyk A.,Warsaw University of Technology | Jaroszewicz Z.,Institute of Applied Optics | Jaroszewicz Z.,National Institute of Telecommunication
Photonics Letters of Poland | Year: 2010

It is a great honor and pleasure to present the readers of Photonics Letters of Poland the first special issue of our journal. This special issue contains an overview of optical research in Latin America. © 2010 Photonics Society of Poland.

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