An improved algorithm for feature extraction from a fingerprint fuzzy image

Proper fingerprint feature extraction is crucial in fingerprint-matching algorithms. For good results, different pieces of information about a fingerprint image, such as ridge orientation and frequency, must be considered. It is often necessary to improve the quality of a fingerprint image in order for the feature extraction process to work correctly. In this paper we present a complete (fully implemented) improved algorithm for fingerprint feature extraction, based on numerous papers on this topic. The paper describes a fingerprint recognition system consisting of image preprocessing, filtration, feature extraction and matching for recognition. The image preprocessing includes normalization based on mean value and variation. The orientation field is extracted and Gabor filter is used to prepare the fingerprint image for further processing. For singular point detection, the Poincaré index with a partitioning method is used. The ridgeline thinning is presented and so is the minutia extraction by CN algorithm. The paper contains the comparison of obtained results to the other algorithms

Anion radicals of [60]fullerenes. An EPR study

Photochemically induced electron transfer in homogeneous systems (using triethylamine donor) and heterogeneous systems (using photoexcited TiO2 suspension) was applied in in situ reduction of [60]fullerene. The anion radicals generated were characterized by means of EPR and VIS/near-lR spectroscopy. Narrow EPR lines were found. Radical A with gA = 2.0000 and peak-topeak width, PPA = 0.09 mT was observed as the primary product; followed by its consecutive product B with gB = 2.0006, PPB = 0.04 mT, and in some cases product C with gc = 2.0009 and PPc < 0.1 mT.Radical A was assigned to [60]fullerenc mono-anion, also characterized by a near-IR band at 1077 nm.B is presumably di-anion or a dimeric tbrm of mono-anion. Identical results were also obtained using cathodic in situ reduction. Applying these generation techniques to [60]fullerene derivatives produced narrow EPR lines analogous to those described for pristine [60]fullerene. This was the case not only in organic solvents, but also in aqueous solutions. The results obtained present a contrast with the original ex situ EPR investigations describing [60]fullerene mono-anion with wide lines. According to the results presented here, the narrow and wide EPR lines do not represent contradictory phenomena,but are an integral part of the relatively complicated manifestations of various fullerene states and both will have to be seriously considered in the future

Formation of Fe(0)-Nanoparticles via Reduction of Fe(II) Compounds by Amino Acids and Their Subsequent Oxidation to Iron Oxides

Iron nanoparticles were prepared by the reduction of central Fe(II) ion in the coordination compounds with amino acid ligands. The anion of the amino acid used as a ligand acted as the reducing agent. Conditions for the reduction were very mild; the temperature did not exceed 52°C, and the optimum pH was between 9.5 and 9.7. The metal iron precipitated as a mirror on the flask or as a colloid in water. Identification of the product was carried out by measuring UV/VIS spectra of the iron nanoparticles in water. The iron nanoparticles were oxidized by oxygen yielding a mixture of iron oxides. Oxidation of Fe(0) to Fe(II) took several seconds under air. The size and properties of iron oxide nanoparticles were studied by UV/VIS, TEM investigation, RTG diffractometry, Mössbauer spectroscopy, magnetometry, thermogravimetry, and GC/MS

The Chloroacetamido Group as a New Linker for the Synthesis of Hemoprotein Analogues

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