Application of a Three-Stage Procedure for Extracting a Small-Sized Anchor Object on a Noisy Image

The purpose of the article is to develop a three-stage procedure for identifying an anchor object in a noisy current image. This goal is achieved by determining the sampling threshold levels at which the greatest similarity of the compared images is ensured; development of a procedure for refining the maximum of the decision function by quantizing the current image. The solution to the first problem is based on the formation of a correlation field of radio brightness temperatures and the choice of a sampling threshold. It is proposed to use the cross-correlation coefficient as a criterion for the degree of image matching. The effectiveness of the procedure for selecting a fragment of a reference image is assessed based on the criterion of the probability of selecting a fragment of a reference image. It is shown that image noise can lead to a decrease in the probability of selecting a fragment of a reference image, down to 0.4. It is proposed to refine the maximum of the decision function based on the iteration method. The most significant results are the obtained dependences of the probability of choosing a fragment of the reference image on the threshold value and the signal-to-noise ratio, as well as the analytical relation for the asymptote of this dependence. The novelty of the work lies in the fact that the procedure for forming the decisive function has been further developed. This will significantly improve the operating efficiency of unmanned aerial vehicles, especially in conditions of interference

Magnetoelectric ordering of BiFeO3 from the perspective of crystal chemistry

In this paper we examine the role of crystal chemistry factors in creating conditions for formation of magnetoelectric ordering in BiFeO3. It is generally accepted that the main reason of the ferroelectric distortion in BiFeO3 is concerned with a stereochemical activity of the Bi lone pair. However, the lone pair is stereochemically active in the paraelectric orthorhombic beta-phase as well. We demonstrate that a crucial role in emerging of phase transitions of the metal-insulator, paraelectric-ferroelectric and magnetic disorder-order types belongs to the change of the degree of the lone pair stereochemical activity - its consecutive increase with the temperature decrease. Using the structural data, we calculated the sign and strength of magnetic couplings in BiFeO3 in the range from 945 C down to 25 C and found the couplings, which undergo the antiferromagnetic-ferromagnetic transition with the temperature decrease and give rise to the antiferromagnetic ordering and its delay in regard to temperature, as compared to the ferroelectric ordering. We discuss the reasons of emerging of the spatially modulated spin structure and its suppression by doping with La3+.Comment: 18 pages, 5 figures, 3 table

Neural-fuzzy digital controller of energie of electrons for accelator linear

Решена задача нейро-нечеткого цифрового управления энергией электронов для линейного ускорителя ЛУ-40. В разработанном регуляторе используются многослойная нейросетевая модель и правила нечеткого вывода, основанные на матрице нечетких ассоциаций. Для выбора наилучшей архитектуры сети использовалась процедура дискриминации нейросетевых моделей. Результаты моделирования подтверждают работоспособность предложенной схемы цифрового управления.Розглядається метод нейро-нечіткого керування енергії електронів лінійного прискорювача, що базується на використанні нейронної мережі та нечіткого цифрового регулятора. Показано можливість адекватного опису динаміки об’єктів, що досліджуються, за допомогою нейронних мереж. Наведено результати моделювання, що дозволяють зробити висновок щодо ефективності застосування запропонованого підходу у цифрових системах керування лінійним прискорювачем.The method of neural-fuzzy control of energie of electrons for accelateur linear, based on application of neural network and fuzzy controller , is examined. Possibility of adequate description of objects by the neural models got on this method is shown. Results of modeling loud allowing to draw conclusion about efficiency of application of offered approach in the digital control system by accelateur linear

Compression method of images based on discrete wavelet transform

Усовершенствован алгоритм сжатия изображений с потерями для сжатия BMP-файлов. Результаты тестирования показали, что по степени сжатия при сопоставимых значениях PNSR модифицированный алгоритм превосходит существующие аналоги.Удосконалено алгоритм стиснення зображень з втратами для стиснення BMP-файлів. Результати тестування показали, що за ступенем стиснення при порівняних значеннях PNSR модифікований алгоритм перевершує надіснуючі аналоги.The algorithm of lossy image compression to compress BMP-files. Test results showed that the improved is superior over existing counterparts in compression degree with comparable values of PNSR

Nature of phase transitions in ammonium oxofluorovanadates, a vibrational spectroscopy study of (NH4)3VO2F4 and (NH4)3VOF5

Two ammonium oxofluorovanadates, (NH4)3VO2F4 and (NH4)3VOF5, have been in-vestigated by temperature-dependent infrared and Raman spectroscopy methods to determine the nature of phase transitions (PT) in these compounds. Dynamics of quasioctahedral groups was simulated within the framework of semi-empirical approach, which justified the cis-conformation of VO2F43– (C2v) and the C4v geometry of VOF53–. The observed infrared and Raman spectra of both compounds at room temperature (RT) revealed the presence at least of two crystallographically independent octahedral groups. The first order PT at elevated temperatures is connected with a complete dynamic disordering of these groups with only single octahedral state. At lower temperatures, the octahedra are ordered and several octahedral states appear. This PT is the most pronounced in the case of (NH4)3VOF5, when at least seven independent VOF53– octahedra are present in the structure below 50 K, in accordance with the Raman spec-tra. Ammonium groups do not take part in PTs at higher and room temperatures but their reorientational motion freezes at lower temperatures