The paper describes the method for determining the position of the contact wire of electrified railways using microwaves. The method is based on the triangulation system of two georadars and allows to determine a contact wire zigzag and height from the rail head. The proposed method is all-weather with the possibility of continuous monitoring of the overhead contact wire in plan and profile with the opportunity to automate the processing and signaling abnormalities.
Keywords: railroad contact line, contact wire location, GPR, automatic control systems
By self-propagating high-temperature synthesis (SHTS) prepared fine powder оf La2-xSrxNiO4 composition , which is used to obtain dense ceramics exhibiting the properties of n-type semiconductor. Prolonged annealing of the samples resulted in a decrease of the conductivity on the order of 3-4, and the changing nature of the dielectric spectrum: dielectric constant ε' has a stable value of 4·104 Hz in the range of 0,4 − 1·105 Hz .
Keywords: dielectric constant, phase separation, nikelate of strontium lanthanum, self-extending high-temperature synthesis
The article presents an approach to synthesis of inhibitory quasi-fields of obstacles for SUGV on-board path planning system, algorithmic basis of which is an adaptive control method for intellectual robots. The inhibitory quasi-fields of obstacles are used for path optimization by safety criteria.
Keywords: Robotics, SUGV, local navigation, path planning, trajectory optimization
A model is presented for the calculation of thermoelastic stress and displacement in semiconductor structures
due to laser processing. Developed software based on the model allows to determine the optimal parameters of laser processing with taking into account the physical and topological parameters of the structure. The model is divided into two tasks: the non-stationary heat conduction equation is solved, and the equilibrium equations and Hooke's law. For equations solution was used the finite difference method.
Keywords: Laser processing, thermal stress, finite difference method
An original mathematical model describing different activities of actors in the vertical marketing system is presented. They are a provider, a agent, a trading enterprise are presented as a controlling subjects. The model is based on the game-theoretical and hierarchical approach. An equilibrium of Germeyer G1 game in terms of sustainable development is established. The method of impulsion is used as a method of hierarchical control to solve this model. The main system operation laws based on numerical experiments are presented.
Keywords: game theory, hierarchical, three-level control system, method of impulsion
Questions of the classification soil and groundwater conditions were considered as an important factor of a selection of types and designs of machines for clearing forest areas from a tree and scrub vegetation. Taking into account the executed analysis the classification of the conditions was proposed the application of machines for clearing the forest area.
Keywords: Tree and scrub vegetation, soil and groundwater conditions, clearing the forest area
The article discusses issues related to the development of the optimal structure of neural networks. One of the major problems in the synthesis neural conrollers is ensuring optimal number of neurons and connections between layers in the network. Necessary to achieve a compromise between the representational network capabilities, and memory that will be required to store it. The article presents a number of heuristics, allowing to reach such a compromise by limiting the number of connections for each neuron.
This is done through the introduction of two characteristics for the neuron: the radius of the coverage and density of connections. Coverage radius determines the number of neurons that could potentially have a connection to this neuron, and the density of the compound gives the actual number of such compounds. Altogether, these characteristics determine the amount of synaptic connections, which can have a neuron. The article presents the heuristics that allow to define these characteristics depending on the network structure.
Keywords: neural network, neural controller, associative memory, machine learning, optimization
The article presents a mathematical model of deformation of thin-walled conical shells, considering orthotropic material, geometric nonlinearity and transverse shear. Showing geometric relationships, physical relationships, the functional of total energy of deformation and boundary conditions.
Keywords: conical shell, tapered panel, mathematical model, geometric nonlinearity, orthotropic, lateral shifts
This paper presents mathematic model of optimization of expenses of stock-piling of timber and logging timber from felling areas to timber consumers by transport networks. This model optimize technological processes which appears during the process of stock-piling of timber and logging timber.
Keywords: log truck, rail transportation in timber processing complex.
The method of laser therapy is based on synchronization of phases of inflow (anacrotism) and outflow of blood (catacrotism) in the field of the pathological center with phases of a being narrowed and extending laser spot on a projection of this pathological center. It is supposed that being narrowed on a projection of the pathological center the spot of laser light stimulates blood inflow to the spot center, and the extending spot of a laser beam – activates blood outflow in the direction from the spot center to its periphery. The developed technique of the automated correction of hemodynamic frustration consists in pilot signal formation (in charge of the power and laser positioning) for the laser machine on the basis of a difference between a reference rheogram and a rheogram of the patient (a body site) in real time.The offered technique has to allow to use more efficiently methods of laser therapy at treatment of violations of a blood-groove. The technique is calculated on the basis of numerical experiment by means of methods of mathematical model operation.In the real experiment the question of synchronization of the reference and measured signal is considered solved though this task represents a subject of separate researches.The received pilot signal can be in real time transformed to the current signal operating positioning and laser power.The method gives the chance of an operating control of a condition of the patient and blood-groove diagnostics to, in time and after a session of laser therapy. Development provides possibility of adaptive individual correction and optimization of parameters of influence during a session and a course of treatment.
Keywords: laser, therapy, technique, rheogram, diagnostics, blood-groove, management, signal
Nonstoichiometric tungsten oxides WO3–x and oxide alkaline tungsten bronzes have been studied because of their potential applications in electrochromic devices such as solar panel arrays and “smart windows”. Different phases of
WO3–x have been considered. In this part we present results of our research which clearly show that all Magneli phases of tungsten oxides WOx (namely W40O118, W20O58, W5O14, W18O49, W8O23, W3O8) and oxide tungsten bronzes MxMyWO3 at M-Li, Na, K, Rb, Cs. They are characterized by metal – like properties. Their band structures display an energy gap in the valence band just below the Fermi level.
We present results of our electrochemical synthesis of tungsten oxide bronzes in ionic melts of the polytungsten salts. Among the new state – of – the art methods for their manufacture, electrochemical synthesis in ionic melts, which makes considerably better use of existing technologies, is highly productive, based on the discharge of oxyanions of the polytungstates.
Keywords: oxide alkali bronzes, alkaline tungsten bronzes, tungsten, molybdenum, nonstoichiometry, tungsten oxides, electroconductivity, electrochromism
Based solutions of avalanche transit diode amplifier for under the influence of microwave amplitude- modulated optical signal at the p-n junction diode is determined by the response of the amplifier , while a detector device characteristic. We investigate the influence of numerous system parameters on product detection.
Keywords: frequency response; avalanche diode; amplifier; detector; Microwave amplitude modulated optical vibration .
The article presents the results of experimental investigations of carbon fabric electrodes for recording electrical biosignals. Experimental studies of carbon fabric electrodes showed good results both in conductivity and usability, for example, for further integration into clothing, that indicates the high quality of carbon fabric electrodes and promising for further uses for cardiac monitoring.
Keywords: Electrodes, carbon fabric, electrical biosignals, cardiac monitoring.
The paper describes the development and research of MEMS sensors error model using experimental data approximation of fourth degree polynomial with coefficients computed by least square method and written using of graphical programming language LabVIEW
Keywords: Navigation, MEMS sensors, error model.
This article discusses problem of improving performance of large dimension random number generators. With current trends , as an accelerator for CPU considered field-programmable gate array ( FPGAs ) . The analysis of hardware implementations of algorithms of random number generators offered by the Altera company is carried out. It is offered to use a method of calculation of a gain of productivity Reconfigurable Amenability Test (RAT) offered by B. Holland, K. Nagarajan and A. D. George. Assessment of several random number generators is made by this method. Received results it is analyzed, and on the basis of the drawn conclusions, simulation of the algorithms showing a high rate of a gain of productivity is made. Results received theoretically and during simulation are compared.
Keywords: Reconfigurable amenability test, field-programmable gate array, random number generator, high-performance calculating performance prediction