Parallel Fuzzy Inference Method for Higher Order Takagi–Sugeno Systems

A fuzzy logic inference method is proposed for higher-order Takagi–Sugeno systems with applying the order reduction operation to rules. The possibility of using hierarchical fuzzy higher-order systems to decrease the number of rules and to parallelize fuzzy inference is analyzed. The method is implemented in an intelligent software system to speedup computations in the problem of evaluating investment projects.     

Effect of Austenitizing Temperature on Pearlite Transformation of a Medium-Carbon Steel

Metallurgist - Pearlite transformation is a necessary step in the production of ultra-high strength wires and nanostructured bainitic steels. The initial austenite grain size has an important...     

Impulse response approximation of digital finite impulse response filter with delay line units

This article proposes special digital filtering structures formed by one multiplier, one adder and a delay line. Such structures can be used to synthesize finite impulse response Hilbert filter. The advantage of such approach is reduced number of multipliers, compared to standard implementation. The quotients of structures can be calculated by local optimization methods. This article shows an example of the 30-th order Hilbert filter calculation, which requires only 6 multipliers for implementation.     

High-voltage pulse discharge propagating along a water surface

The results are presented of experimental studies of electrical discharge occurring in the atmosphere along a free water surface between a spike above the water surface and a remote submerged electrode during quasi-rectangular high voltage pulses. Three stages of such discharge are identified, and the stage of the discharge gliding along the water surface is investigated.     

Kinetic regularities of ozone decomposition in water

The paper studied the impact of the pH and temperature on kinetics of ozone decomposition in water. It has been shown that in the pH range 4 to 8 it is well described by the equation of the second order reaction. At an increase of the pH and temperature the rate of ozone decomposition increases. The relationship between the logarithm of the constant and the pH at 19°C corresponds to the equation log k_(pH) = −0.7 + (0.49 ± 0.03)(pH 4). The energy of ozone decomposition activation constitutes 76.0 ± 8.3 kJ/mol. The presence in the solution of phosphate ions and tert-butyl alcohol substantially increases the rate of the decomposition chain process.     

Tribological Performance of Ti–Si-Based in Situ Composites

In this study, a series of Ti–Si-based in situ composites was manufactured by means of a common argon arc melting technique and tribologically evaluated using a sliding ball-on-disc tester under simulated body fluid lubrication. The composite microstructure, mechanical properties, and surface roughness were characterized using light and scanning electron microscopy (SEM), vertical scanning interferometry (VSI), X-ray diffraction (XRD) analysis, and hardness measurements. The evolution of coefficients of friction (COFs) and the appearance of contacting surfaces showed that two the principal wear mechanisms were mixed elastohydrodynamic lubrication (EHL), typically followed by abrasive wear. The mixed EHL was due to the combined effect of serum solution lubrication and surface irregularities, which were produced during the routine surface preparation of samples. The mixed EHL provided the absence of wear and low and stable COFs, which did not depend on the phase composition, microstructure, or hardness of Ti–Si-based alloys. However, in most cases, the change in contact geometry led to the transition from mixed EHL to conventional boundary lubrication, accompanied by increased and unstable friction, adhesive material transfer of metal to the ceramic counterbodies, and abrasive wear. In this respect, the low wear resistance and high adhesion affinity of the titanium matrix of Ti–Si-based alloys should be improved.     

Category-theoretic formalization in designing fuzzy intelligent systems

A complex of problems related to the category-theoretic formalization of fuzzy UML diagrams, fuzzy graphs, and fuzzy-graph transformation systems is examined. The basic constraints that must be satisfied by UML diagrams, which are the basis of fuzzy models of intelligent systems, are investigated. The category-theoretic approach is used to analyze the properties of inference specification based on a distributed system of fuzzy-graph transformations. Means for the compositional construction of fuzzy systems are developed using morphisms and categories of fuzzy graphs.     

Development and experimental validation of automatic radar recorder of the number and speed of vehicles for opposite traffic directions

The designing of a continuous wave radar (CW) intended for remote counting of traffic (remote traffic counter) and speed measurement of vehicles using speed trajectories in the radar beam for long-range transferring of these data is considered. It was experimentally shown that, for recording the current number of vehicles and measuring the speed of each of them in both traffic directions, it is more expedient to use a CW radar rather than an FMCW radar (frequency modulation continuous wave radar). A CW radar is more immune to noises of the receiver and the interferences formed due to the offset of the phase and amplitudes at quadrature outputs of the IQ mixer, the lateral lobes of the antenna directivity diagram, and interfering reflections from low Doppler and stationary targets. The circuit and the signal processing software for the CW radar have been developed. The CW design proposed by the authors is currently implemented based on the Xilinx FPGA programmable logic integrated devices (PLD) entering the working radar prototype.     

Rheology of Superplastic Ceramics

Constitutive equation of rheology describing a phenomenological level of superplastic deformation as functional correlation between tensor components of stress and strain rate has been analyzed for the case of superplastic ceramic flow. Rheological properties of material are taken into account by means of scalar rheological coefficients of shear and volume viscosity, which are functions of temperature, effective stress (or strain rate) and density of material.