RESEARCH ON THE FRACTAL STATISTICAL CHARACTERISTICS AS POSSIBLE PROGNOSTIC PARAMETERS FOR EARTHQUAKES, GENERATED IN THE SEISMIC ZONE OF VRANCEA, IN THE PERIOD BETWEEN 01.08.2016 AND 30.12.2016

Using fractal analysis is an excellent alternative method for decode the seismic noise structure. Fractal analysis of microseismic noise could also be an appropriate method to detect earthquake indicators. The scientific goal is to detect standard signals, based on different earthquakes’ focal mechanisms, separating the "individual" behavior of the elements of the monitoring systems.The method for describing low-frequency microseismic noise from the network of seismic stations in a seismically active region of the Vrancea used. Seismic records of twenty-three broadband stations were analyzed, situated at distances of 20 to 500 km from the Vrancea earthquakes whit magnitudes Mw=5.7 and Mw=5.6 on September 23 and December 27, 2016, respectively. The daily assessment values of three multifractal parameters (characteristics of the multifractal singularity spectra of the waveform) from each station used for the description.The present paper is a continuation of previous work [Oynakov et al., 2019], where the effects of synchronization in the low-frequency microseismic field were found before the Vrancea earthquake with magnitude Mp=5.6 on October 28, 2019.The study shows that the noise coherence measure increased for stations, closer to the epicenter. However, the question of the source of this coherence remains open.Using fractal analysis is an excellent alternative method for decode the seismic noise structure. Fractal analysis of microseismic noise could also be an appropriate method to detect earthquake indicators. The scientific goal is to detect standard signals, based on different earthquakes’ focal mechanisms, separating the "individual" behavior of the elements of the monitoring systems.The method for describing low-frequency microseismic noise from the network of seismic stations in a seismically active region of the Vrancea used. Seismic records of twenty-three broadband stations were analyzed, situated at distances of 20 to 500 km from the Vrancea earthquakes whit magnitudes Mw=5.7 and Mw=5.6 on September 23 and December 27, 2016, respectively. The daily assessment values of three multifractal parameters (characteristics of the multifractal singularity spectra of the waveform) from each station used for the description.The present paper is a continuation of previous work [Oynakov et al., 2019], where the effects of synchronization in the low-frequency microseismic field were found before the Vrancea earthquake with magnitude Mp=5.6 on October 28, 2019.The study shows that the noise coherence measure increased for stations, closer to the epicenter. However, the question of the source of this coherence remains open

Phase transitions and phase diagram of the ferroelectric perovskite NBT-BT by anelastic and dielectric measurements

The complex elastic compliance and dielectric susceptibility of (Na_{0.5}Bi_{0.5})_{1-x}Ba_{x}TiO_{3} (NBT-BT) have been measured in the composition range between pure NBT and the morphotropic phase boundary included, 0 <= x <= 0.08. The compliance of NBT presents sharp peaks at the rhombohedral/tetragonal and tetragonal/cubic transitions, allowing the determination of the tetragonal region of the phase diagram, up to now impossible due to the strong lattice disorder and small distortions and polarizations involved. In spite of ample evidence of disorder and structural heterogeneity, the R-T transition remains sharp up to x = 0.06, whereas the T-C transition merges into the diffuse and relaxor-like transition associated with broad maxima of the dielectric and elastic susceptibilities. An attempt is made at relating the different features in the anelastic and dielectric curves to different modes of octahedral rotations and polar cation shifts. The possibility is also considered that the cation displacements locally have monoclinic symmetry, as for PZT near the morphotropic phase boundary.Comment: 11 pages, 9 figures, submitted to Phys. Rev.

On stress/strain state in a rotating disk

In the framework of mechanics of continuum bodies, the problem of stress/strain state in a high-speed rotating disk of constant thickness has been considered. The material of the disk is assumed to be homogeneous, elastic/perfectly-plastic. In the plastic zone, the stresses and plastic strains are related by some associated law similar to the one employed in deformation theory of plasticity. The general algorithm of the solution covers any smooth plasticity function. At some steps of the algorithm, it is possible to get analytical expressions, particularly, for the quadratic Mises yield criterion. For the given model, the notion of control parameters (external and internal) has been introduced. The allowable boundaries of external parameters have been defined as well. For some states of the disk, the coherent values of external parameters have been obtained. The results are represented graphically to show various states of the disk. The usage of piecewise plasticity functions has been briefly discussed. The results obtained can be used in preliminary engineering design and related numerical codes.info:eu-repo/semantics/publishedVersio

THE CLINICAL SIGNIFICANCE OF MATRIX METALLOPROTEINASES IN RHEUMATOID ARTHRITIS PATIENTS (REVIEW OF THE LITERATURE AND OUR OWN DATA)

Matrix metalloproteinases (MMPs) are a group of over 20 proteolytic enzymes responsible for cleavage of protein components of the extracellular matrix. Three types of MMPs play an important role in the development of joint damage in patients with rheumatoid arthritis (RA): collagenases (MMP1, 8 and 13), stromelysins (MMP3), and gelatinases (MMP9). MMP3 is considered to be one of the key mediators of joint damage. Increased serum level of MMP is not specific for RA and may be registered in other rheumatic diseases (osteoarthritis, psoriatic arthritis, gout, ankylosing spondylitis, systemic lupus erythematosus); however, monitoring of the level of MMP is of particular clinical importance in patients with RA. MMP3 serum level may be a useful marker of disease activity. Several studies have shown a correlation of MMP3 concentration with clinical and laboratorial parameters of inflammatory activity (ESR and C-reactive protein – CRP) in RA patients. The elevated level of MMP3 is associated with radiological changes in joints and can also be a predictor of severe destructive lesions in RA patients. Evaluation of the MMP3 level can also be useful for monitoring the therapy effectiveness using both standard disease-modifying antirheumatic drugs (DMARDs) and genetically engineered biological drugs (GEBD). Thus, evaluation of MMP3 concentration is useful for assessing disease activity and efficacy of treatment with DMARDs and GEBD, as well as for predicting the severity of destructive changes in joints

AUTOIMMUNE RHEUMATIC DISEASES: RESULTS AND PROSPECTS FOR RESEARCHES

According to the present-day views, autoimmunity is a complex pathological process, the essence of which is intolerance and hence a pathological immune response to intrinsic tissue components (autoantigens), which underlies the pathogenesis of a broad spectrum of human autoimmune diseases. Recently, diverse immune disorders underlying autoimmune rheumatic diseases (ARD) and syndromes have been revealed; an association has been found between the development of ARD and autoinflammatory diseases and syndromes; a classification of human immunoinflammatory diseases has been elaborated. The paper considers the results of the authors’ investigations of ARD treatment with innovative biologics, the pathogenetic mechanisms and diagnosis of ARD, by conducting immunological and molecular biological studies of a wide range of molecular and cellular biomarkers (autoantibodies, acute phase proteins, cytokines, chemokines, vascular endothelial activation markers, complement system components, lymphocyte subpopulations, bone and cartilage tissue metabolic products, genetic, epigenetic, transcriptomic markers), and approaches to personalized treatment of ARD

Оптимизационные модели и алгоритмы для сетевых задач распределения ресурсов

Запропоновано ефективні алгоритми нелінійного програмування для задач розрахунку мереж, а також побудовано нові мережеві моделі для визначення оптимальних потоків і розподілу ресурсів. Розглянуто задачі з нелінійними цільовими функціями загального вигляду та мережевою структурою обмежень, що дало змогу охопити єдиним підходом достатньо широкий спектр мереж. Для розрахунків застосовано модифікації добре відомих методів нелінійного програмування. Запропоновані методи першого порядку зіставні за швидкістю збіжності з методами послідовного квадратичного програмування за рахунок ефективного алгоритму розв’язання допоміжних квадратичних задач та зручної процедури обчислення крокового множника. Проаналізовано та чисельно протестовано серію моделей задач розподілу ресурсів, що враховують замовлення споживачів, змінну продуктивність джерел постачання та наявність тимчасових сховищ продукту. Порівняння результатів розрахунку прикладних задач із застосуванням стандартного пакета Solver та спеціально створеної комп’ютерної програми за методом лінеаризації Б.М. Пшеничного продемонструвало можливість зменшення кількості ітерацій у процедурах одного порядку в декілька разів. Побудовані моделі та алгоритми оптимізації потокорозподілу дають змогу створювати ефективні інформаційно-аналітичні системи для оптимального керування функціонуванням мережевих розподільчих систем.The efficient algorithms for nonlinear programming problems for calculating networks have been offered, as well as the new network models to determine the optimal flows and distribution of resources have been constructed. The problems with nonlinear objective functions of general form and network structure of restrictions, which allow reaching quite a wide range of networks using common approach, were considered. For calculations the modifications of well-known methods of nonlinear programming were applied. The proposed methods of the first order is comparable by convergence rate with the methods of sequential quadratic programming through an efficient algorithm for the solution of the auxiliary quadratic problems and convenient procedure of step factor calculation. A series of models of resource distribution problems, taking into account the customers’ orders, the variable performance of sources and temporary storage of the product, was analyzed and numerically tested. The comparison of calculation results of applied problems using a standard package Solver and a specially designed computer program by the method of linearization of B.M. Pshenichniy demonstrated the possibility of reducing the number of iterations in the procedures of the same order by several times. The constructed models and algorithms of optimization of flow distribution allow creating effective information-analytical system for optimum control of functioning of the network distribution systems.Предложены эффективные алгоритмы нелинейного программирования для задач расчета сетей, а также построены новые сетевые модели для определения оптимальных потоков и распределения ресурсов. Рассмотрены задачи с нелинейными целевыми функциями общего вида и сетевой структурой ограничений, что позволило охватить единым подходом достаточно широкий спектр сетей. Для расчетов применены модификации хорошо известных методов нелинейного программирования. Предложенные методы первого порядка сопоставимы по скорости сходимости с методами последовательного квадратичного программирования за счет эффективного алгоритма решения вспомогательных квадратичных задач и удобной процедуры вычисления шагового множителя. Проанализирована и численно протестирована серия моделей задач распределения ресурсов, учитывающих заказы потребителей, переменную производительность источников и наличие временных хранилищ продукта. Сравнение результатов расчета прикладных задач с применением стандартного пакета Solver и специально созданной компьютерной программы по методу линеаризации Б.М. Пшеничного продемонстрировало возможность уменьшения количества итераций в процедурах одного порядка в несколько раз. Построенные модели и алгоритмы оптимизации потокораспределения позволяют создавать эффективные информационно-аналитические системы для оптимального управления функционированием сетевых распределительных систем

Wave diffraction problems on periodical sets of heterogeneities in the stratified media

The universal approach to solving the diffraction problems on the periodical set of heterogeneities in the stratified media is proposed. The infinite periodic grating consisting of thin conducting bands embedded into a dielectric plate is considered as an example. The boundary value problem for the quasi-periodic potential functions is equivalent to the pair summatorial functional equation for the Floquet coefficients. At first, it is advisable to solve the auxiliary diffraction problem for the stratified medium in the case when the heterogeneities are moved off. The heterogeneities generate the field perturbation; it is a solution of a similar pair equation. Secondly, we need to define new unknown variables in such way that the pair equation should have the standard form. To get this result we propose to use the boundary value conditions on the heterogeneities. Then the other conditions on the media interface can be transformed to standard form. The dual equation is equivalent to regular infinite set of linear algebraic equations for the coefficients of decomposition of the electromagnetic field by Floquet harmonics. In the case of elastic waves the wave diffraction problems on the periodical sets of heterogeneities can be reduced to vector dual summatorial functional equations. The electromagnetic wave diffraction problems on the periodical knife grating was investigated by analogous scheme