51 research outputs found

    Отказоустойчивый многофазный асинхронный электропривод с несинусоидальными токами

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    Рассмотрен принцип построения многофазного асинхронного электропривода, позволяющего при неоднократных отказах преобразователя частоты и двигателя обеспечить отказоустойчивое управление, на основе программируемых несинусоидальных токов с восстановлением работоспособности за счет активизации алгоритма восстановления в управляющем микроконтроллере. Приведены результаты моделирования для аварийной ситуации типа "обрыв фазы" для случая трехфазного двигателя с частичным восстановлением работоспособности асинхронного двигателя

    Biocompatibility and functionality of a tissue-engineered living corneal stroma transplanted in the feline eye

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    PURPOSE. Corneal tissue shortage has become a major concern worldwide, which has motivated the search for alternative solutions to eye bank human eyes for corneal transplantation. Minimally invasive lamellar transplantation and tissue engineering may offer new opportunities for the rehabilitation of diseased corneas. The aim of this study was to evaluate the biocompatibility and functionality of stromal lamellar grafts tissue-engineered (TE) in vitro and transplanted in vivo in the cornea of a feline model. METHODS. The corneal stromas were engineered in culture from corneal stromal cells using the self-assembly approach, without the addition of exogenous material or scaffold. Eight healthy animals underwent two intrastromal grafts in one eye and the contralateral eye was used as a control. Animals were followed with slit-lamp ophthalmic examination, corneal esthesiometry and optical coherent tomography. Confocal microscopy, immunofluorescence, histology, and transmission electron microscopy (TEM) were performed at 4 months. RESULTS. Four months after transplantation, the TE-stromal grafts were transparent, functional, and well tolerated by the eye. All grafts remained avascular, with no signs of immune rejection, despite a short course of low-dose topical steroids. Corneal sensitivity returned to preoperative level and reinnervation of the grafts was confirmed by confocal microscopy and immunofluorescence. Histology and TEM of the TE-grafts showed a lamellar stromal structure with regular collagen fibril arrangement. CONCLUSIONS. These results open the way to an entirely new therapeutic modality. Intracorneal filling using a biocompatible, transparent, and malleable TE-stroma could be the basis for multiple types of novel therapeutic options in corneal interventional surgery

    Разработка технологии ручной дуговой и механизированной под слоем флюса сварки нахлесточных соединений пластин

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    В выпускной квалификационной работе разработана технология ручной дуговой и механизированной сварки под слоем флюса нахлёсточных соединений пластин из стали 10Г2С1Д, предложено устройство для сварки. Произведены расчеты режимов сварки. В экономической части ВКР выполнен расчет экономического эффекта от внедрения новой технологии. Рассмотрены вопросы безопасности труда производственных рабочих и охраны окружающей среды. Выпускная квалификационная работа бакалавра выполнена в текстовом редакторе Microsoft Word 2016In final qualifying wok the technology of manual arc and mechanized welding under a layer of flux of lap joints of plates from steel 10G2C1D, is developed, the device for welding is suggested. Calculations of welding modes are dene. In economic pat of final qualifying work, the calculation of the economic effect from the introduction of new technology is fulfilled. Issues of labor safety of industrial warblers and environmental protection are considered. The final qualifying work is done in a text editor Microsoft word 2016

    Theory of critical first sound near the *-transition of 4He. I. Model and correlation functions

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