Event cognition from the perspective of cognitive development

Event cognition is a rapidly developing and promising research area. Meanwhile, some domains are not considered in detail in this scope. In particular, event cognition is not precisely explored from the perspective of cognitive development. In this paper, we compare the capacity to cut a visual narrative into events for kindergarten students, primary school students, high school students and adults. “The pear film” by W. Chafe (1975) is used as the material for our experiment. We also examine a correlation between event comprehension and other cognitive skills for primary school students. Our work provides clear evidence that, in contrast with high school students and adults, kindergarten students and primary school students perceive visual narrative on the surface level

An evolution equation as the WKB correction in long-time asymptotics of Schrodinger dynamics

We consider 3d Schrodinger operator with long-range potential that has short-range radial derivative. The long-time asymptotics of non-stationary problem is studied and existence of modified wave operators is proved. It turns out, the standard WKB correction should be replaced by the solution to certain evolution equation.Comment: This is a preprint of an article whose final and definitive form has been published in Comm. Partial Differential Equations, available online at http://www.informaworld.co

ВДОСКОНАЛЕНИЙ АЛГОРИТМ КОМУТАЦІЇ КОМІРОК БАГАТОКОМІРКОВОГО ТРАНЗИСТОРНОГО ПЕРЕТВОРЮВАЧА

In order to improving the load current profile of multicell-type transistor converter with combined linear and switch control the enhanced algorithm of unified cells commutation was proposed. Simulation was used for investigating the converter operation. The results of simulation confirmed that the use of the enhanced algorithm allows to obtain the load current profile, that is maximally similar to reference signal. References 3, figures 5.С целью улучшения формы тока нагрузки многоячеичного транзисторного преобразователя с общим использованием непрерывного и импульсного способов управления предложен усовершенствованный алгоритм коммутации унифицированных амбарчиков преобразователя. С помощью имитационного моделирования проведено исследование работы преобразователя, в результате чего установлено, что использование усовершенствованного алгоритма коммутации ячеек позволяет получить форму тока нагрузки, максимально приближенную к сигналу задания.З метою покращення форми струму навантаження багатокоміркового транзисторного перетворювача зі спільним використанням безперервного та імпульсного способів керування запропоновано вдосконалений алгоритм комутації уніфікованих комірок перетворювача. За допомогою імітаційного моделювання проведено дослідження роботи перетворювача, в результаті чого встановлено, що використання вдосконаленого алгоритму комутації комірок дозволяє отримати форму струму навантаження, максимально наближену до сигналу завдання

СТІЙКІСТЬ КОМБІНОВАНОЇ СИСТЕМИ НАКОПИЧЕННЯ ЕНЕРГІЇ НА ОСНОВІ СУПЕРКОНДЕНСАТОРА ТА АКУМУЛЯТОРНОЇ БАТАРЕЇ

The aim of the work is to analyze the stability of the battery-supercapacitor hybrid storage of power supply for resistance micro-welding equipment, considering the possible variation of the system parameters and taking into account parallel series resistance of the circuit components. Methodology. The sufficient accurate mathematical model of the hybrid energy storage system to stability analysis has been obtained by the state-space average method. According to the state-space averaging method, PWM switching converters are described by separate circuit topologies for each switching period. The system of differential equations for each time interval has been derived by use of the Kirchhoff rules. The small-signal model transfer function of the SEPIC converter has been obtained by applying the Laplace transform to linear state equations averaged over one switching cycle. Finally, the Nyquist stability criterion has been considered to evaluate the stability of the proposed energy storage system. Results. Bode diagrams of an open-loop system for different values of the duty cycle, average load current, and input voltage have been obtained by using MATLAB software. The gain margin ranges from 14.6 dB to 26.4 dB and the phase margin ranges from 45.4 degrees to 54.8 degrees. From these results, it is obvious that the proposed system meets the stability criteria regardless of the aforementioned parameter fluctuations. Originality. The high-efficiency energy storage system for micro resistance welding technology has been proposed. Developing of the energy storage system according to the battery semi-active hybrid topology enables to control the Li-ion battery discharge current within the maximum allowable value. SEPIC converter utilization ensures the high-efficient operation of the power supply despite the battery charge state. Moreover, this topology allows implementing series and parallel configuration of both batteries and supercapacitors to obtain the required value of voltage and current. Practical significance. The mathematical model of the SEPIC converter has been developed by applying the state-space averaging technique. The stability analysis for parameter variation, such as duty cycle and the average load current, the input voltage has been performed by using Nyquist criteria. В роботі розглянуто комбінований ємнісний накопичувач енергії на основі акумуляторної батареї (АБ) та суперконденсатора джерела живлення для установки контактного мікрозварювання. Для забезпечення рівномірного споживання струму від АБ обрано напівактивну топологію АБ та перетворювач SEPIC (Single-Ended Primary-Inductor Converter). Методом усереднення в просторі змінних стану аналітично отримано математичну модель системи. З метою проведення аналізу стійкості комбінованого накопичувача при різних значеннях коефіцієнта заповнення імпульсів, струму навантаження та напруги АБ отримано передавальну характеристику системи керування. Результати аналізу показали, що запропонована система є стійкою при зміні параметрів у встановлених межах.

Heterogeneity of population of microorganisms grown in presence of iron oxide maghemite nanoparticles

In this work γ-Fe2O3 MNPs were obtained by laser target evaporation and water based suspensions were prepared. Maximum permissive dose of iron in water (MPD) is 0.3 mg/L. It was found that 100 MPD dose of iron induces formation of non-typical colonies after 72 or 96 hours exposition: against a background of small black colonies large white colonies appeared due to a disruption in tyrosine synthesis. Multiple re-cloning of the white colonies grown with MNPs showed that they retained their properties both under standard conditions (temperature of 24 °C) and at the temperatures up to 37o C. E.nigrum grown with MNPs demonstrated very scant extension of small colonies at the cultivation temperature of 24o C, their growth was completely blocked at 37°C. Significant changes in the structure of the population were noted. First of all, large cells with pronounced aggregation were observed among the black colonies. These aggregates consisted of large cells connected to each other by matrix. In the white colonies the appearance of very long threadlike cells connecting different groups of the cells establishing an intercellular communication was evident. Fe2O3 MNPs induce an increase in the heterogeneity of the population, expressed as a change in morpho-physiological states. © 2018 The Authors, published by EDP Sciences.The work was supported by the Ministry of Education and Science of the Russian Federation (project No. 3.6121.210 )7 and R FFI №16-34-015 92 grant s. e tW hank R ndrA ade, Iu. Novoselova and I.V. Beketov for special support. Selected measurements were made at ISG KER services UPV/EHU

Regularities of ultrasonography of suspensions of alumina nanoparticles in biological media

This paper studies the echo-contrast properties of an alumina nanopowder suspension using ultrasonography (US) fully corresponding in its characteristics to the techniques of medical ultrasound diagnostics of organs and tissues. The purpose of this study was to search for the possible effect of the ionic and protein composition of the biological medium on the intensity of the reflected echo signal of the contrast material based on nanoparticles. It was found that the pH of the blood promotes the maximum use of echo contrast options of alumina nanopowder suspensions. Particle size measurements in the suspension using the dynamic light scattering technique showed the stabilizing effect of blood serum and plasma on the nanopowder suspension, resulting in the attenuation of the echo signal. The data offer a basis for the development of new contrast materials based on nanoparticles for the ultrasound imaging of the heart and blood vessels. The considered mechanisms of the established phenomena make it possible to elucidate the processes of interaction of metal oxide nanoparticles with biological molecules. © 2013 Pleiades Publishing, Ltd

Hysteroscopic metroplasty: current status of the problem

Hysteroscopic metroplasty is very important for the restoration of the normal anatomy of the uterus, creation of the conditions for favorable obstetric outcomes. This review of the current scientific papers on the topic summarizes the data on the indications, preoperative preparation, and techniques of hysteroscopic metroplasty. It also presents the information on the approaches to the evaluation of the effectiveness of this kind of surgery, peculiarities of the postoperative care, preventive treatment of the intra- and postoperative complications. The paper provides state-of-the art information on the importance of the hysteroscopic metroplasty for the reproductive health of a woman and peculiarities of the gestation course after the dissection of the intrauterine septum.Гистероскопическая метропластика имеет важное значение для восстановления нормальной анатомии матки, создания условий для благоприятных акушерских исходов. В обзоре данных современной литературы обобщены сведения о показаниях, предоперационной подготовке, методах гистероскопической метропластики. Приведена информация о способах оценки эффективности данной операции, особенностях ведения послеоперационного периода, профилактики интра- и послеоперационных осложнений, а также представлены современные сведения о значении гистероскопической метропластики для репродуктивного здоровья женщины, особенностях течения беременности после рассечения внутриматочной перегородки

Evaluation of External and Internal Threats to Sanitary-Epidemiological Welfare of the Population in the Context of Mass Sporting Events

Mass gatherings (MGs) always incur some kind of potential hazard associated with incipiency of emergency situations with sanitary-epidemiological bias (ES). Upcoming Universiade (World Student Games) in Kazan (July, 2013) raises an issue of implementation of a unified system of approaches to the effective provision of sanitary-epidemiological welfare of the population, taking due account of peculiarities and specific conditions under which the MG will be conducted. Therewith key objective of this study has been formulated as elaboration of the system based on epidemiological assessment of real and potential threats at the MG. Analyzed have been the data on 37 MGs carried out over the period of 25 years since 1987 up to 2012; investigated is epidemiological situation in 170 participating states. Worked out is a scheme of qualitative determination of potential epidemiological threat on the basis of comprehensive assessment of epidemiological risks in the endemic territories of the troubled regions. Distinguished is a complex of measures for the provision of sanitary-epidemiological welfare when managing the Universiade in Kazan heedful of high potential epidemiological hazard of this event

Baikal-GVD: status and prospects

Baikal-GVD is a next generation, kilometer-scale neutrino telescope under construction in Lake Baikal. It is designed to detect astrophysical neutrino fluxes at energies from a few TeV up to 100 PeV. GVD is formed by multi-megaton subarrays (clusters). The array construction started in 2015 by deployment of a reduced-size demonstration cluster named "Dubna". The first cluster in its baseline configuration was deployed in 2016, the second in 2017 and the third in 2018. The full scale GVD will be an array of ~10000 light sensors with an instrumented volume of about 2 cubic km. The first phase (GVD-1) is planned to be completed by 2020-2021. It will comprise 8 clusters with 2304 light sensors in total. We describe the design of Baikal-GVD and present selected results obtained in 2015-2017.Comment: 9 pages, 8 figures. Conference proceedings for QUARKS201