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Leonov V.V.,Ufa State University of Economics and Service
Journal of Engineering Physics and Thermophysics

Consideration has been given to the electrodynamic aspects of stationary diffusion mass transfer in condensed media with the aim of improving electrometric approaches to determination of the physicochemical properties of substances in a condensed state. © 2014 Springer Science+Business Media New York. Source

Krymsky V.G.,Ufa State University of Economics and Service | Ivanov I.V.,Ufa State Aviation Technical University
Safety and Reliability of Complex Engineered Systems - Proceedings of the 25th European Safety and Reliability Conference, ESREL 2015

The paper proposes a novel approach to deriving Non-Homogeneous Poisson Process (NHPP) models for software failure prognostics. Importantly, this approach makes no use of the regular requirement for the expression for the Fault Detection Rate (FDR) to be completely known a priori. Instead, it uses unified scheme of NHPP models, maximum likelihood method and expert judgment to start the prognostic procedure and find estimates of the cumulative (integrated) FDR in a sequence of time moments. The procedure continues with analysis of accumulated data represented by Interval-valued Time Series (ITS) within exponential smoothing framework. The values of smoothing coefficients are found by solving a constrained optimization problem with the aid of L-BFGS-B algorithm. The results of ITS analysis lead to interpretation of software re-liability characteristics in terms of interval-valued probabilities which lower and upper bounds are obtained with respect to cumulative FDR estimates in definite time points. The approach is illustrated by a numerical example. © 2015 Taylor & Francis Group, London. Source

Nurislamova L.F.,Russian Academy of Sciences | Gubaydullin I.M.,Russian Academy of Sciences | Koledina K.F.,Russian Academy of Sciences | Safin R.R.,Ufa State University of Economics and Service
Reaction Kinetics, Mechanisms and Catalysis

The purpose of this study was to develop a kinetic model for the Cp2ZrCl2-catalyzed hydroalumination of olefins with organoaluminum compounds HAlBu2 i, AlBu3 i, ClAlBu2 i (Bu = C4H9, Cp = C5H5). Experimental data were taken from previous investigations in which the catalytic reaction was carried out with various olefins and different initial amounts of the catalyst in the temperature range from 0 to 40 °C. A mathematical model of the process was developed taking into account the material balance. The rate constants and activation energies for process steps were determined by solving the inverse problem of chemical kinetics. The kinetic patterns of the catalytic hydroalumination of olefins with organoaluminum compounds were studied in terms of the constructed reaction model. © 2015, Akadémiai Kiadó, Budapest, Hungary. Source

Bikbulatova A.A.,Ufa State University of Economics and Service
Izvestiya Vysshikh Uchebnykh Zavedenii, Seriya Teknologiya Tekstil'noi Promyshlennosti

The article provides information on the relevance of designing women's everyday clothes that helps to prevent diseases of alvus and the internals of lumbus. The thickness of the bundle of materials based on a body's heat sensation, activity and ambient temperature is substantiated experimental. Source

Krymsky V.G.,Ufa State University of Economics and Service
International Journal of Performability Engineering

In this paper we propose a novel approach to deriving uncertainty model in reliability applications. It is based on a state space representation of the system life cycle which is similar to techniques widely used in the control theory (CT). Such a model in turn allows applying CT methods (e.g., optimal control algorithms) to assess the reliability in case of high level of uncertainty. In particular, a CT-based model is effective even if the system performances cannot be described in terms of single-valued statistical characteristics. We demonstrate that in such a situation a CT-based model combined with the so-called 'interval-valued probabilities' becomes a very promising tool for reliability computations. © RAMS Consultants Printed in India. Source

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