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The object of research is the seed material and working bodies of a vibro-pneumatic centrifugal separator; the subject is their interaction. The established surfaces, which are the results of the simulation of the process of separation of seed materials in the vibro-pneumatic centrifugal separator, have a curve to the plane whose parameters are the speed of the air flow and the frequency of oscillations of the working surface. It is noted that this nature of the dependence of the purity of the «heavy» fraction of seeds on parameters of the separation process makes it possible to determine the rational ranges of these parameters, at which the maximum value of this characteristic is reached. Experimental simulation of the separation process in the vibro-pneumatic centrifugal separator of wheat, sunflower, and soybean seed materials under production conditions showed a high convergence of the results with the results of the simulation of the process under the same initial conditions. It was established that the correlation coefficients between the points obtained experimentally and obtained by simulation for the given results are in the range from 0.89 to 0.95. At the same time, the differences are the purity values of the «heavy» seed fraction, and not in the nature of its change due to changes in the parameters of the separation process. The expediency of using modeling when determining the rational values of the parameters of the separation process in the vibro-pneumatic centrifugal separator is noted. This will help increase the energy and resource efficiency of the equipment due to the absence of the need for experimental setup. The rational ranges of air flow speed and vibration frequency of the rotor of the vibro-pneumatic centrifugal separator for the separation of seed materials have been determined: wheat – 1.2...1.5 m/s; 4500...5100 cycles per minute; sunflower – 1.3...1.5 m/s; 4500...5000 cycles per minute; soybeans – 1.3...1.6 m/s; 5000...5500 cycles per minute [ABSTRACT FROM AUTHOR]

In order to increase an athlete’s organism functional reserves we created the innovative technology based on low-frequency vibrations influence on respiratory system. First we measured acoustic impedance of an athlete’s organism for three phases of respiration at polyharmonic acoustic signal within the range of frequency from 3 Hz to 51 Hz. After that during 2 weeks we organized six sessions of bioacoustical stimulation among the group of 20 athletes, divided into subgroups with an effective (130 dB) and placebo (60 dB) effect. It was stated that six-fold effect of a scanning tonal signal with the level of sound pressure 130 dB within the range 22-36 Hz led to resonance frequency of respiratory system increase, respiratory system sound vibrations imbibitio coefficient decrease and its resistance to sound wave increase because of reserve alveoli opening and the increase of area of cross section of alveolar ways and respiratory bronchial tubes.

Specific problems arising, when Von Neumann type computer is used as feedback element, are considered. It is shown, that due to specifics of operation this element introduce pure lag into control loop, and lag time depends on complexity of algorithm of control. Method of evaluation of runtime between reading data from sensors of object under control and write out data to actuator based on the theory of semi- Markov process is proposed. Formulae for time characteristics estimation are obtained. Lag time characteristics are used for investigation of stability of linear systems. Digital PID controller is divided onto linear part, which is realized with a soft and pure lag unit, which is realized with both hardware and software. With use notions amplitude and phase margins, condition for stability of system functioning are obtained. Theoretical results are confirm with computer experiment carried out on the third-order system.

This paper explores the evolution of peer-to-peer systems (P2P) and their future implications. Essential background in both centralized and decentralized P2P architectures is presented. The major P2P networks are identified [...]

A novel method for recognition of breathing patterns of bioradiolocation signals breathing patterns (BSBP) in the task of noncontact screening of sleep apnea syndrome (SAS) is proposed and implemented on the base of wavelet transform (WT) and neural network (NNW) applications. Selection of the optimal parameters of WT includes determination of the proper level of wavelet decomposition and the best basis for feature extraction using modified entropy criterion. Selection of the optimal properties of NNW includes defining the best number of hidden neurons and learning algorithm for the chosen NNW topology. The effectiveness of the proposed approach is tested on clinically verified database of BRL signals corresponding to the three classes of breathing patterns: obstructive sleep apnea (OSA); central sleep apnea (CSA); normal calm sleeping (NCS) without sleep-disordered breathing (SDB) episodes. [ABSTRACT FROM AUTHOR]

The current climate change, unlike previous ones, is caused by human activity and is characterized by an unprecedented rate of increase in the near-surface temperature and an increase in the frequency and intensity of hazardous weather and climate events. To survive, society must be prepared to implement adaptation strategies and measures to mitigate the negative effects of climate change. This requires, first of all, knowledge of how the climate will change in the future. To date, mathematical modelling remains the only method and effective tool that is used to predict the climate system's evolution under the influence of natural and anthropogenic perturbations. It is important that mathematics and its methods and approaches have played a vital role in climate research for several decades. In this study, we examined some mathematical methods and approaches, primarily, mathematical modelling and sensitivity analysis, for studying the Earth's climate system, taking into account the dependence of human health on environmental conditions. The essential features of stochastic climate models and their application for the exploration of climate variability are examined in detail. As an illustrative example, we looked at the application of a low-order energy balance model to study climate variability. The effects of variations in feedbacks and the climate system's inertia on the power spectrum of global mean surface temperature fluctuations that characterized the distribution of temperature variance over frequencies were estimated using a sensitivity analysis approach. Our confidence in the obtained results was based on the satisfactory agreement between the theoretical power spectrum that was derived from the energy balance model and the power spectrum that was obtained from observations and coupled climate models, including historical runs of the CMIP5 models. [ABSTRACT FROM AUTHOR]

This article concerns the optimal control problem for internal gravitational waves in a model with additive "white noise". This mathematical models based on the stochastic Sobolev equation, Dirichlet boundary conditions, and a Cauchy initial condition. The inhomogeneity describes random heterogeneities of the medium and fluctuations. By white noise we realize the Nelson-Gliklikh derivative of the Wiener process. The study was carried out within the framework of the theory of relatively bounded operators and the theory of Sobolev-type stochastic equations of higher order and the theory of (semi) groups of operators. We show the existence and uniqueness of a strong solutions, and obtain sufficient conditions for the existence of an optimal control of such solutions. The theorem about the existence and uniqueness of the optimal control is based on the works of J.-L. Lyons. [ABSTRACT FROM AUTHOR]