This book examines the theoretical and practical aspects of tribological process using synergy, fractal and multifractal methods, and the fractal and multifractal models of self-similar tribosystems developed on their basis. It provides a comprehensive analysis of their effectiveness, and also considers the method of flicker noise spectroscopy with detailed parameterization of surface roughness friction. All models, problems and solutions are taken and tested on the set of real-life examples of oil-gas industry. The book is intended for researchers, graduate students and engineers specialising in the field of tribology, and also for senior students of technical colleges.
This book summarizes the results of years of research on the problem of strength and fracture of polymers and elastomers. It sets out the modern approach to the strength theory from the standpoint of fractals, the kinetic and thermodynamic theories as well as the meso-mechanic destruction. The dimension reduction method is applied to model the friction processes in elastomers subjected to the complex dynamic loading. Finally, it analyses a relation between the fracture mechanism and the relation phenomena, and provides new experimental data on the sealing nodes in accordance with their specific working conditions where the effect of self-sealing is observed.
The history of describing natural objects using geometry is as old as the advent of science itself, in which traditional shapes are the basis of our intuitive understanding of geometry. However, nature is not restricted to such Euclidean objects which are only characterized typically by integer dimensions. Hence, the conventional geometric approach cannot meet the requirements of solving or analysing nonlinear problems which are related with natural phenomena, therefore, the fractal theory has been born, which aims to understand complexity and provide an innovative way to recognize irregularity and complex systems. Although the concepts of fractal geometry have found wide applications in many forefront areas of science, engineering and societal issues, they also have interesting implications of a more practical nature for the older classical areas of science. Since its discovery, there has been a surge of research activities in using this powerful concept in almost every branch of scientific disciplines to gain deep insights into many unresolved problems. This book includes eight chapters which focus on gathering cutting-edge research and proposing application of fractals features in both traditional scientific disciplines and in applied fields.
This book is a compendium of fundamental mathematical concepts, methods, models, and their wide range of applications in diverse fields of engineering. It comprises essentially a comprehensive and contemporary coverage of those areas of mathematics which provide foundation to electronic, electrical, communication, petroleum, chemical, civil, mechanical, biomedical, software, and financial engineering. It gives a fairly extensive treatment of some of the recent developments in mathematics which have found very significant applications to engineering problems.
Issue 01 Oct-Nov-Dec 2013 The Multi-Fructural Analysis Of Fatigue Failure Under Friction Process A.M. Pashayev, A.Kh. Janahmadov, O.A. Dyshin, M.Y. Javadov The article shows the need to combine approaches of synergetics and fractals in the study of friction and wear in the frictional contact, due to fact that dissipative structures, self-organising in the open systems, are known to have a fractal behaviour The multi-fractal concept allows to introduce new quantitative structures, characterised by a spectrum of generalised fractal dimensions and reflected by the degree of randomness. Different levels of structure (micro-, mesa- and macro-scale) are described in the framework of multi-fractal analysis. A procedure to calculate the multi-fractal dimension of this structure is developed and the results of the numerical calculations are submitted.Research Of Loading Distribution On Coils Of Running Pair Of The LatchN.H.JavadovIt is given the calculation procedure of distribution of pressure on coils of running pair of latch at various loading schemes. Recommendations are provided for the choice of loading schemes of running pair, which ensures more uniform distributions and therefore, considerably reduces the wear of coils by means of constructive changes in a latch. Modeling And Forecasting The Financial Markets Using Theory Of Deterministic Chaos And Fractals S.M. Javadova This paper presents the results of the multi-fractal analysis based on the wavelet transformation, which can be considered as method of studying the spectral correlation properties of various processes, including non-stationary. Comparative experience with methods MFFA (multi-fractal fluctuation analysis) and WTMM (wavelet transform modulus maxima) in studying of the multi-fractal properties of signals of time function shows that MFFA method is more reliable and robust.As an instrument of the ‘local’ study of time function structure, WTMM allows to evaluate the correlation properties of random processes in comparison with a short signal. Surface Structures Of Frictional Materials On Asbestosfree Base M.I. Aliyev Development of asbestosfree composite materials on petroleum coke base enabled to obtain environmentally sound products with sufficiently high physical, mechanical and tribotechnical characteristics. The materials have been analyzed/tested from the perspective of physicochemical friction mechanics in the breaking mode through the differential-thermal analysis (DTA) and thermogravimetric analysis (TGM), supplemented with the study of friction materials structure. The thermogravimetric analysis findings indicated that decomposition of the new asbestosfree friction material begins after 14 minutes at 3000C.
Issue 04 July-Aug-Sept 2014 Diagnosis Of The Contact Interaction Of Solid Bodies At Friction Using Fractal Analysis Methods A.Kh. Janahmadov, M.Y. Javadov, O.A. Dyshin Were developed the additional quantitative research tools of the surface roughness: the fractal dimension of curvature on the bearing surface and the fractal dimension of profilograph. These values are used to classify the regimes of the contact interaction of the metal elements at friction and to diagnose the form of contact according to the fractal dimensions scale, which describes the main three types of contacts: elastic, elastic-plastic and plastic. The Stock Price Valuation Based On The Stochastic Modeling Of Financial Data S.M. Javadova The stochastic model is developed to forecast a movement of stock prices as function of the Wiener process. The canonical decomposition of function values through discrete number of points is used to generate the Wiener process. Factors Causing Corrosion And Destruction of Coating in Operation of Oil-Field Pump N.G. Javadov, A.M. Mehtiev The paper review and analyzes factors that contribute towards corrosion and destruction of coating during operation of oil-field pump. It is noted that factors such as cold, moisture, heat, corrosive components of pumped fluid, mechanical stress, etc., have negative impact. Relations Of Cytokine Blood Spectrum With Nephropathy At Patients With Diabetes A.N. Babakhanova Work objective is to study the cytokine status of patients with diabetes of type 1 and type 2 with a complicated nephropathy and an uncomplicated course. 123 patients with diabetes and the control group of 20 people were inspected. By the immune-enzyme analysis of ELISA the levels (INF-γ, TNF-α, IL-6, IL-1β) were determined in blood serum of the patients. The most expressed changes of the cytokine status were observed in the patients of diabetes of type 1 and type 2 which were expressed in the initial increase of the maintenance of all studied pro-inflammatory cytokines (INF-γ, TNF-α, IL-6, IL-1β). Such changes in activation of the pro-inflammatory cytokines characterize this disease as an inflammatory immune-dependent process. The changes in the cytokine status had a non-uniform character with the most expressed changes in IL-1β, TNF-α, INF-γ synthesis (p ≤ 0,001) and a slight increase of IL-6.
In our present era of nanoscience and nanotechnology, new materials are poised to take center stage in dramatically improving friction and wear behavior under extreme conditions. Compiled by two eminent experts, Self-Organization During Friction: Advanced Surface-Engineered Materials and Systems Design details the latest advances and developments i
Many scientists and engineers do not realize that, under certain conditions, friction can lead to the formation of new structures at the interface, including in situ tribofilms and various patterns. In turn, these structures-usually formed by destabilization of the stationary sliding regime-can lead to the reduction of friction and wear. Friction-I
Just 23 years ago Benoit Mandelbrot published his famous picture of the Mandelbrot set, but that picture has changed our view of the mathematical and physical universe. In this text, Mandelbrot offers 25 papers from the past 25 years, many related to the famous inkblot figure. Of historical interest are some early images of this fractal object produced with a crude dot-matrix printer. The text includes some items not previously published.
