Ufa State University of Economics and Service

Ufa, Russia

Ufa State University of Economics and Service

Ufa, Russia
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Denisova O.A.,Ufa State University of Economics and Service | Chuvyrov A.N.,Bashkir State University
Crystallography Reports | Year: 2013

The effects of electrohydrodynamic instability (EHDI) in smectic C liquid crystals in an electric field are studied. The objects of study are oriented layers of para-hydroxybenzoic acid possessing a smectic phase. The observed effects are divided into three groups according to the character of the motion of molecular centers of mass and the orientation of the director and the smectic C liquid crystal layers. The instabilities of the azimuthal and Kapustin-Williams domains are experimentally found. The experimental cell consists of two glass plates with tin dioxide electrodes separated by Mylar spacers of a specified thickness. Various schemes of domain rotation are considered. The EHDI is found to depend on the layer geometry. © 2013 Pleiades Publishing, Ltd.


Arslan A.,Technical University of Istanbul | Tari E.,Technical University of Istanbul | Ziatdinov R.,Fatih University | Ziatdinov R.,Ufa State University of Economics and Service | Nabiyev R.I.,Fatih University
Computer-Aided Design and Applications | Year: 2014

Log-aesthetic curves (LACs), which are generally used in industrial design for aesthetic shape modeling, are examined for implementation as transition curves despite their non-trivial representation in terms of incomplete gamma functions, or Fresnel integrals which appear in the parametric equations of a certain spirals. The family of log-aesthetic curves includes well-known spirals as Euler, Nielsen, logarithmic spiral, and involutes of a circle. The horizontal geometry of the route can contain classical transition curves, which are formed by transition curve-circular arc-transition curves. In order to compare the examined family of log-aesthetic transition curves with the classical transition curve in terms of vehicle-road kinematics, the curvature and superelevation functions are derived, and functions of lateral change of acceleration (LCA) curves are obtained and illustrated graphically using a constant motion model. The discontinuities in the form of jumps in the graphs of the lateral change of acceleration are taken into consideration in order to compare log-aesthetic curves and clothoids. © 2014 CAD Solutions, LLC.


Manapov R.S.,Ufa State University of Economics and Service | Shulyakovskaya D.O.,Ufa State University of Economics and Service | Dolomatov M.Y.,Ufa State Petroleum Technological University
Chemistry and Technology of Fuels and Oils | Year: 2016

Correlations have been found between some physicochemical properties of diesel fractions and color coordinates in the sRGB color space profile, permitting the rapid determination of relative density, flash point, and initial boiling point of the diesel fractions from photoimages. The suitability of this method was shown by statisticalanalysis. This method can find application for prompt monitoring of the quality of diesel fractions during refinery operations. © 2016 Springer Science+Business Media New York


Rakhimova E.B.,Russian Academy of Sciences | Ismagilov R.A.,Russian Academy of Sciences | Zainullin R.A.,Ufa State University of economics and Service | Galimzyanova N.F.,Russian Academy of Sciences | Ibragimov A.G.,Russian Academy of Sciences
Russian Journal of Applied Chemistry | Year: 2013

A procedure was developed for preparative synthesis of α,ω-bis- 1,5,3-dithiazepanes by heterocyclization of aliphatic α,ω-diamines with N,N,N',N'-tetramethylmethanediamine and 1,2-ethanedithiol. The fungicidal activity of 1,2-bis(1,5,3-dithiazepan-3-yl)ethane and 3,3'-(3,6-dioxaoctane-1,8- diyl)bis-1,5,3-dithiazepane toward microscopic fungi affecting agricultural plants was studied. © Pleiades Publishing, Ltd., 2013.


Krymsky V.G.,Ufa State University of Economics and Service
International Journal of Performability Engineering | Year: 2014

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.


Bikbulatova A.A.,Ufa State University of Economics and Service
Izvestiya Vysshikh Uchebnykh Zavedenii, Seriya Teknologiya Tekstil'noi Promyshlennosti | Year: 2014

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.


Leonov V.V.,Ufa State University of Economics and Service
Journal of Engineering Physics and Thermophysics | Year: 2014

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.


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 | Year: 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.


Latypova F.M.,Ufa State University of economics and Service | Tuktarova I.O.,Ufa State University of economics and Service | Katamanov V.L.,Ufa State University of economics and Service | Tsyrulnik R.F.,Ufa State University of economics and Service
Procedia Engineering | Year: 2015

The article proposes the method of obtaining sulphides concentrate from petroleum product consisting in hydrogenation of thiophene derivatives of petroleum distillates into sulphides and their subsequent extraction. The structural-group composition of concentrates extracted from the initial and hydrogenated distillates has been explored. © 2015 Published by Elsevier Ltd.


Krymsky V.G.,Ufa State University of Economics and Service
Chemical Engineering Transactions | Year: 2013

Failure prognostics being performed for any complex industrial system typically meets serious obstacles caused by uncertainty. This uncertainty actually has a hierarchical structure due to the peculiarities of its influence to the prognostics results. Namely, to quantify the chances of a system failure we normally have to apply probabilistic (non-deterministic) model. Such a model reflects the randomness and the diversity of the factors initiating a failure (the 'first order uncertainty'). However the estimated probability of the failure may differ from its real value by the so-called 'bias'. So the imperfectness of the probabilistic models becomes the source of the 'second order uncertainty'. This means that the interval-valued probabilities can often describe the reality more adequately than single valued ones. The paper presents the novel approach to system life prognostics based on the usage of the intervalvalued statistical characteristics. The problem statement remarkably has many features similar to those considered in the classical publications on the theory of imprecise probabilities. Nevertheless the methodology used to find the prognostics result is very different and involves the technique from the optimal control theory. It relies on the state space representation of the system life cycle and Pontryagin's principle of maximum modified to optimization problems with the integral and non-integral types of constraints. This novelty allows generalizing the ways to process additional information on the system reliability efficiently and makes the resulted intervals for the probability values tighter. In turn the decrease of the corresponding imprecision provides favorable conditions for justified decisions on the failure prevention, e.g. maintenance planning. Copyright © 2013, AIDIC Servizi S.r.l.

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