National University of Food Technologies

nuft.edu.ua
Kiev, Ukraine

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Bovsunovsky A.,National University of Food Technologies | Surace C.,Polytechnic University of Turin
Mechanical Systems and Signal Processing | Year: 2015

The main purpose of the present review paper is to illustrate the principal achievements of numerous researchers who have studied the non-linear effects caused by a closing crack in the most common types of structural elements such as beams, shafts and plates, the aim being to assess the potential and future prospects of using non-linear behaviour to detect damage. Indeed, for a wide range of practical applications, in order to avoid catastrophic failure, the development of diagnostics techniques which are sufficiently sensitive to incipient cracks in structures and machines is a crucial issue. The main potential advantage of using vibration diagnostics based on the use of non-linear effects is the relatively high sensitivity to the damage of the closing crack type, especially for application to beam-like structures and rotating shafts; instead the potential for application to plate-like structures has been found to be limited. After analysing the state-of-art on this subject in detail, a discussion of the respective merits, drawbacks and prospects of a range of non-linear vibration methods for structural damage detection is presented. The general conclusion which can be drawn from the highly encouraging results of recent research is that further development of these techniques for non-destructive testing of structures with closing cracks would be highly worthwhile. © 2015 Elsevier Ltd. All rights reserved.


Legeza V.P.,National University of Food Technologies
Mechanics of Solids | Year: 2012

Free vibrations of a heavy homogeneous cylinder rolling in a cylindrical cavity whose directing curve is a brachistochrone are considered. The equation of motion of the cylinder is derived and the circular frequency of free vibrations of the cylinder center of mass is determined. An analogy between the cycloidal pendulum with a rolling cylinder and the classical cycloidal pendulum in the form of a material point is obtained. © 2012 Allerton Press, Inc.


Bovsunovsky A.P.,National University of Food Technologies
Journal of Physics: Conference Series | Year: 2015

The investigations of cracks growth in the fractured turbine rotors point out at theirs fatigue nature. The main reason of turbine shafts fatigue damage is theirs periodical startups which are typical for steam turbines. Each startup of a turbine is accompanied by the connection of turbine generator to electrical network. During the connection because of the phase shift between the vector of electromotive force of turbine generator and the vector of supply-line voltage the short-term but powerful reactive shaft torque arises. This torque causes torsional vibrations and fatigue damage of turbine shafts of different intensity. Based on the 3D finite element model of turbine shaft of the steam turbine K-200-130 and the mechanical properties of rotor steel there was estimated the fatigue damage of the shaft at its torsional vibrations arising as a result of connection of turbine generator to electric network.


Legeza V.P.,National University of Food Technologies
Mechanics of Solids | Year: 2010

The motion of a heavy homogeneous cylinder is considered as a no-slip rolling along the desired curve. We obtain a functional in the form of the total time of the cylinder rolling and solve the corresponding variational problem of minimizing this functional. We obtain an algebraic equation for the directional line of steepest descent, brachistochrone, in parametric form. We use the equation of motion of the cylinder with constraint reaction to determine the conditions of implementation of its pure rolling without separation and slip with respect to the brachistochrone. © Allerton Press, Inc., 2010.


Zmievskii Yu.G.,National University of Food Technologies
Petroleum Chemistry | Year: 2015

A laboratory setup has been designed to create the same excess hydraulic pressure at both membrane sides. This setup has been used for the whey ultrafiltration permeate/distilled water system to determine the critical pressure at which pores of an MFFK-3 hydrophobic membrane (Vladipor, Russia) are filled with the liquid phase. This value has been found to be 0.6 MPa. On the basis of several assumptions, it has been supposed that, the membrane pores are partially filled with the liquid phase on the both sides before attaining the critical pressure. This filling leads to a reduction in the distance between the meniscuses of the "hot" and "cold" solutions inside the pore, thereby being theoretically capable of enhancing the membrane flux. The liquid entry pressure (LEP) of this membrane has been also determined, being 130 and 50 kPa for distilled water and whey ultrafiltration permeate, respectivey. © 2015 Pleiades Publishing, Ltd.


Bovsunovsky A.,National University of Food Technologies
Engineering Fracture Mechanics | Year: 2012

In a result of experimental investigations of steel R2M cylindrical specimens with a surface transverse and slant crack at torsional vibrations it was revealed that the damping characteristic of the specimens is strongly dependent on the crack sizes and stress amplitude. The energy dissipation in the non-propagating transverse crack is caused mainly by the plastic area along the crack front and practically is not related to the friction between the crack faces. The level of energy dissipation in this crack is determined uniquely by the equivalent stress intensity factor. © 2012 Elsevier Ltd.


Legeza V.P.,National University of Food Technologies
Mechanics of Solids | Year: 2010

We consider low-frequency vibrations of a vibroprotective system of rigid bodies consisting of a roller vibration suppressor and a movable carrying body under the action of an external harmonic excitation. We write out the dynamic equations of the common motion of the damper working body along the hinged roller and of the carrying body. We propose a graphical method for determining the optimal adjustment parameters of the roller damper, which is part of the vibroprotective system. © 2010 Allerton Press, Inc.


Stepanchuk S.O.,National University of Food Technologies
Actual Problems of Economics | Year: 2015

The article defines the contents of contemporary views on intellectual potential of industrial enterprises. Theoretical perspectives have been substantiated with regard to the formation of the structure of intellectual potential. Based on statistical data the current state of intellectual potential of food industry enterprises is analyzed. Directions for further development of intellectual potential of the food industry are presented. © Svitlana O. Stepanchuk, 2015.


Lutsiak V.,National University of Food Technologies
Economic Annals-XXI | Year: 2015

Introduction. Development of fundamental marketing methodology is a key problematic aspect of work of small production enterprises in view of their strengths as well as modern marketing activity techniques adapting for performance at specific production fields and economic activities. Therefore, the objectives of this paper are to analyse current conceptual approaches that form a theoretical and practical background for marketing activities of a small production enterprise and development of quality function deployment in view of correlation between a marketing-mix and primary production. Materials and methods. The results were obtained using dynamic capabilities concept at an enterprise; summarizing method was applied to estimate the role of innovative capacity for activities of small production enterprises and the meaning of quality for competition; the marketing models of goods were used as well as the customer's psychological behaviour pattern in development of the marketing-mix and the quality function deployment technique. Results. As a result of the research, the principles of marketing methodology of a small production enterprise have been theoretically proved. Due to the development of quality function deployment technique, the possibility to obtain a correlation between a complex of organizational marketing and primary production has been practically shown by the example of chosen food industry enterprise. Conclusions and proposals. Practical aspect of the proposed methodology usage is to specify methods of characteristics selecting that are used in the process of quality function deployment, aimed at providing product quality and meeting the needs of customers in different industrial branches. © Institute of Society Transformation, 2015.


Piankova O.,National University of Food Technologies
Economics and Sociology | Year: 2014

The article presents the results of research on the development of international and Ukrainian brands, and also analyzes food and beverages brands position in the Interbrand rankings and UkrBrand. Moreover, the research studies the dynamics of their value and the representation of world’s leading brands on the Ukrainian market in order to identify global trends and characteristics of development in Ukraine. © 2014, (publisher). All rights reserved.

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