Modeling of "groove" rolling defect on internal surface of pipes at lengthwise rolling

The research has been conducted in pipe forming at rolling off by lengthwise rolling mill with stub mandrel; the patterns of change in dimensionless parameters were determined, which characterize deformation in side angle depending on http://www.multitran.ru/c/m.exe?t=424995_2_1elongation ratio. The model of formation of lengthwise groove on internal surface of pipes has been proposed

Electrical discharges in the atmosphere of Venus

Data received from Venera 11 and 12 experiments involving the electrical activity of the atmosphere of Venus show that the electrical discharges occur in the cloud layer. Their energy is roughly the same as in terrestrial lightning, but with a pulse repetition frequency of the discharges which is much greater

ВЕРИФИКАЦИЯ ЭКОНОМЕТРИЧЕСКОЙ МОДЕЛИ С УЧЕТОМ АПРИОРНЫХ ОГРАНИЧЕНИЙ НА СТРУКТУРНЫЕ ПАРАМЕТРЫ

The article describes a method for verification of a statistical model, which, firstly, is represented by the time series of original data and, secondly, is linear in the estimated parameters. Experience in statistical calculations on real empirical data shows that the most well-known and conventionally used in the econometric modeling of mathematical-statistical methods (least squares, maximum likelihood method, and similar methods) often do not ensure successful verification of theoretically required forms of econometric models. The developed method which is called an alternative method of linear regression (AMLR) provides an account of a priori restrictions on the absolute values and signs of the parameters identified by the model. The AMLR based on the concept of best linear index, is known in the theory of statistics from the end of the 1950s. Mathematically AMLR it based on the method of principal components. The article analyzes conditions for applying the AMLR in econometric modeling and methods of transformation of the initial statistical information to ensure correct application of the developed evaluation procedures.Special problems of the proposed method are to determine the level of accuracy of approximation of the dependent variable of the model. In this regard, to assess the level of precision of the statistical model verifiable by using the AMLR, was developed an original method of decomposition of the time series on the regular and stochastic components. The author analyzes the properties of the proposed method of decomposition and gave a numerical illustration of its use in econometric calculations.В статье описан метод верификации статистической модели, которая, во-первых, представлена временными рядами исходных данных и, во-вторых, является линейной по оцениваемым параметрам. Опыт статистических расчетов на основе реальных эмпирических данных свидетельствует о том, что наиболее известные и традиционно применяемые в практике эконометрического моделирования математико-статистические методы (метод наименьших квадратов, метод максимального правдоподобия и близкие к ним методы) очень часто не позволяют обеспечить успешную верификацию теоретически требуемых форм эконометрических моделей. Разработанный метод, называемый альтернативным методом линейной регрессии (АМЛР), обеспечивает учет априорных ограничений абсолютных значений и знаков параметров идентифицируемой модели. В основе АМЛР лежит концепция наилучшего линейного индекса, известная в теории статистики с конца 1950-х годов. В математическом отношении АМЛР основывается на методе главных компонент. Проанализированы условия применения АМЛР в эконометрическом моделировании и методы преобразования исходной статистической информации, обеспечивающие корректность применения разработанной процедуры оценивания.Специальной проблемой предложенного метода является определение уровня точности аппроксимации зависимой переменной модели. В связи с этим для оценки уровня точности статистической модели, верифицируемой при помощи АМЛР, разработан оригинальный метод декомпозиции временного ряда на регулярную и стохастическую компоненты. Проанализированы свойства предлагаемого метода декомпозиции и дана числовая иллюстрация его применения в эконометрических расчетах

Application of Microsecond Voltage Pulses for Water Disinfection by Diaphragm Electric Discharge

The paper presents the dependence of copper and silver ions formation on the duration of voltage pulses of diaphragm electric discharge and on the pH of treated liquid medium. Knowing it allows one to create an automatic control system to control bactericidal agent's parameters obtained in diaphragm electric discharge reactor. The current-voltage characteristic of the reactor with a horizontal to the diaphragm membrane water flow powered from the author`s custom pulse voltage source is also presented. The results of studies of the power consumption of diaphragm electric discharge depending on temperature of the treated liquid medium are given

Dynamics of the Free Surface of a Conducting Liquid in a Near-Critical Electric Field

Near-critical behavior of the free surface of an ideally conducting liquid in an external electric field is considered. Based on an analysis of three-wave processes using the method of integral estimations, sufficient criteria for hard instability of a planar surface are formulated. It is shown that the higher-order nonlinearities do not saturate the instability, for which reason the growth of disturbances has an explosive character.Comment: 19 page

Измерение динамики межотраслевых связей на основе эконометрического метода

Methodological and instrumental problems of working-out a system of econometric calculations that provide the construction of retrospective time series of indicators of inter-industry relations of the domestic economy are considered. The calculation system is based on the joint use of reporting data on inter-industry relations of the domestic economy for any particular year (or years) and data on the dynamics of gross output of activities included in the inter-industry table available in state statistics. This problem can be represented in the form of a system of linear equations in which the number of sought variables to be determined (in this case, the sets of weather values of the inter-industry cost coefficients) exceeds the number of equations (i.e., balance identities for each year of the retrospective period). A special modification of the linear regression model - a model with time-varying structural parameters was applied to generate time series of indicators of inter-industry ties. The econometric method described in the work provides for the disaggregation of the well-known dynamic series of intermediate consumption (at constant prices) in the economy as a whole on the indicators of intermediate consumption (also at constant prices) for certain types of economic activity (economic value). The specified information is not available in state statistics. The developed econometric method provides, further, the disaggregation of time series of the total indicators of intermediate consumption of certain types of economic activity calculated by separate flows of costs (at constant prices) within each given economic value presented in the symmetric table ≪Input-output≫. The numerical results of using the developed calculation system are presented as applied to the construction of time series of intermediate consumption of the real sector and the services sector of the domestic economy for 2004-2016.В статье рассмотрены методические и инструментальные проблемы, связанные с разработкой системы эконометрических расчетов, обеспечивающей построение ретроспективных динамических рядов показателей межотраслевых связей отечественной экономики. Указанная система расчетов основывается на совместном использовании отчетных данных о межотраслевых связях отечественной экономики за какой-либо отдельный год (или годы) и данных о динамике валовых выпусков видов деятельности, включаемых в межотраслевую таблицу, имеющихся в государственной статистике. Данная задача представима в виде системы линейных уравнений, в которой число искомых переменных, подлежащих определению (в данном случае это наборы погодовых значений коэффициентов межотраслевых затрат) заведомо превосходит число уравнений (то есть балансовых тождеств за каждый год ретроспективного периода). Для генерирования временных рядов показателей межотраслевых связей применена специальная модификация линейной регрессионной модели - модель с переменными во времени структурными параметрами. Изложенный в работе эконометрический метод обеспечивает дезагрегацию известного динамического ряда промежуточного потребления (в постоянных ценах) по экономике в целом на показатели промежуточного потребления (также в постоянных ценах) по отдельным видам экономической деятельности (ВЭД). Указанная информация в государственной статистике отсутствует. Разработанный эконометрический метод обеспечивает далее дезагрегацию полученных расчетным путем динамических рядов суммарных показателей промежуточного потребления отдельных ВЭД на отдельные потоки затрат (в постоянных ценах) в рамках каждой данной ВЭД, представленной в симметричной таблице ≪затраты-выпуск≫. Представлены численные результаты использования разработанной системы расчетов применительно к построению динамических рядов промежуточного потребления реального сектора и сферы услуг отечественной экономики за 2004-2016 гг

Targeted training of the function of walking according to the stance and single support phase in patients in the early recovery period of cerebral stroke

Background: The phases of support and single support on a limb are significant basic parameters of walking (phase of support means the whole limb support time, while the phase of single support is when only one limb is on the ground). Both can be used as targets for biofeedback training. Aim: to investigate the effectiveness of both target parameters for training the function of walking with biofeedback in patients in the early recovery period of cerebral stroke. Methods: The study involved 40 patients, 20 in each group, who underwent a training course to harmonize walking: the first group for the period of support, and the second group for the period of single support. The control group of healthy people also consisted of 20 people. We studied the spatiotemporal parameters of walking at an arbitrary pace at the beginning and after the end of the training course, as well as classical clinical scales. The treadmill training consisted of 10 sessions. Results: The clinical and biomechanical parameters of walking changed their values in the direction of a significant improvement in the performance. At the same time, the biomechanical parameters of the second group indicated a more severe functional state before the start of the treatment, with the same clinical parameters according to the Barthel scale, Rivermead Mobility Index, modified Rankin scale, rehabilitation routing scale, and manual muscle testing. In the first group, indirect data were obtained on the possible effect of the target indicator on the training and direct data on its effect on the function of a healthy limb, which also allows increasing the load on the paretic one. In the second group, there were no reliable data on the effect of biofeedback training on the functional outcome. Conclusion: The conducted study showed that the classical clinical assessment of the patient's condition may not correspond to the instrumental functional study of walking. When using the support period as the training target parameter, indirect evidence was obtained that such a training is effective

Lifelong Learning in the System of Higher Education: the State of the Problem and the Strategy of Integrating Educational Activities and Research

The authors of this article consider the current situation of lifelong learning education in leading Russian universities and define some possible strategies for integrating scientific research with educational activities. The empirical bases were: 1) statistical data on the activities of educational institutions of higher education (N = 1180), 2) dataset of monitoring the activities of universities participating in the federal academic leadership programme “Priority-2030”, 3) dataset of a survey of heads of centers for further vocational education in Russian universities (N = 450) as part of the Project “Monitoring of education markets and organizations (MEMO)”. The authors identified strategies for combining scientific and educational activities for lifelong learning programs at universities in the interests of the development of individual consumers, enterprises and branches of the national economy. The authors also found that universities take into account the social needs of society and the preferences of employers, but to a very small extent focus on transforming their scientific results into a new educational product for mass consumers. The significant focus of universities on research activities to a certain extent hinders the development and launch of new education programs, however, it is a group of research universities that demonstrates a higher cost of programs sold. The authors consider, how universities can be focused on working with the population or industry enterprises, integrating the research results into the modules of education programs, and stimulating an increase in the number of teachers combining research and teaching activities, at realizing the third University’s mission and taking into account the research grant volume

Solar neutrino detection in a large volume double-phase liquid argon experiment

Precision measurements of solar neutrinos emitted by specific nuclear reaction chains in the Sun are of great interest for developing an improved understanding of star formation and evolution. Given the expected neutrino fluxes and known detection reactions, such measurements require detectors capable of collecting neutrino-electron scattering data in exposures on the order of 1 ktonne yr, with good energy resolution and extremely low background. Two-phase liquid argon time projection chambers (LAr TPCs) are under development for direct Dark Matter WIMP searches, which possess very large sensitive mass, high scintillation light yield, good energy resolution, and good spatial resolution in all three cartesian directions. While enabling Dark Matter searches with sensitivity extending to the "neutrino floor" (given by the rate of nuclear recoil events from solar neutrino coherent scattering), such detectors could also enable precision measurements of solar neutrino fluxes using the neutrino-electron elastic scattering events. Modeling results are presented for the cosmogenic and radiogenic backgrounds affecting solar neutrino detection in a 300 tonne (100 tonne fiducial) LAr TPC operating at LNGS depth (3,800 meters of water equivalent). The results show that such a detector could measure the CNO neutrino rate with ~15% precision, and significantly improve the precision of the 7Be and pep neutrino rates compared to the currently available results from the Borexino organic liquid scintillator detector.Comment: 21 pages, 7 figures, 6 table