Due to the depletion of the natural base of non-metallic minerals used for the production of high quality aggregates for concrete, and also because of the significant damage to the environment when working sartirovochnyh crushing plants becomes relevant greater use of fine-grained concrete on local , not always of high-quality materials. Rostov region has large reserves of river small and very fine sand , not suitable for the preparation of concrete mixes. The article suggests ways to improve the quality of fine concrete local fine sands with the introduction of their composition from fine mineral filler (the TMN ), the role of which carry waste production and processing opal - carbonate- kristabolitovyh kremnizemistyh flasks Maslovskoye deposit Rostov region. Chosen route of administration mikronaponitelya and optimal dosage , to analyze the impact of THM on Water-solid, water-cement ratio and the strength of concrete .
Keywords: fine-grained concrete on fine sands, mill ground mineral fillers, mikronapolnyayuschy effect flask, gain strength
In this paper, the synthesis of a trajectory regulator for a mini-helicopter are described. We propose a method to hardware-in-the-loop simulation using simulator AerosimRC. The simulation results are showed. The tasks for the application of the method are pointed.
Keywords: position-trajectory regulator, helicopter, mathematical modeling, simulation, algorithms.
Describes the characteristics of the formation of zones zaschischayuschihlinii power, railways, roads, communication lines and other linear structures, passing through forests of trees and shrubs.
Keywords: Key words and phrases: trees and shrubs, protection, linear construction.
Discusses the assessment of the fair price of an option for a generalized model of the Cox-Ross-Rubinstein in the case of m-States. Formulated approval. Based on the findings obtained in the work built a software application that allows you to make calculations.
Keywords: model Cox-Ross-Rubinstein, the fair price of an option risky asset, interest rate
Finding of small concentrations of various gases as an important task for the environment and for the industry. In this paper, investigated gas-sensitive properties of the films of graphene on silicon carbide to NO2 and vapour C2H5OH. The principle of operation of graphene sensor based on the change of electrical conductivity by reason of adsorption of gas molecules. Temperature dependence of the gas desorption from the surface of graphene is obtained. Mode of getting graphene films with the best gas sensing characteristics is defined. The obtained results suggest that graphene is a promising material for gas-sensitive sensors
Keywords: graphene, graphene films on silicon carbide, gas sensor, gas-sensitive of graphene
Considered part of the software and hardware designed and manufactured the device for the automatic analysis of nonlinear parameters of high-temperature superconducting ceramics YBa2Cu3O7-x in variable magnetic fields. Shows the calibration and specifications. The new is a synchronous (the error in determining the phase of no more than 0.5%) of digital signal samples of the nonlinear response of the sample and the samples generated by an external magnetic field (the error is less than 1%), with the number of data samples per channel to 90 ∙ 106 12-bit samples and sampling 600 ∙ 103 samples per second. The reference range of variable magnetic fields 1 - 50 Oe, a frequency range of 1 - 50 kHz in steps of 1 Hz and the accuracy of 0.0291 Hz. The device has an interface to the computer via two USB-interface and original software to work with it. With the use of the device, a series of experiments designed to produce some non-linear parameters of cylindrical sample made of high-Tc ceramic YBa2Cu3O7-x. The analysis of the results and their comparison with the presented in the literature
Keywords: Nonlinear medium, high-temperature superconducting ceramics, synchronous samples, harmonics, ARM-9 CPU, a differential sensor.
In a modified version of the adaptive clutch size of the spacer strength decreases due to a reduction of torque, which transmits the additional friction group, including, for the maximum value of the friction coefficient. Therefore, to save the value of the brace force is necessary to increase the ratio usileniya.Predlozhena concept modernized version adaptvnoy clutch with a combined feedback based on the formalization of the distribution of power factors for the closure of the main steam friction of the friction and more friction groups, allows you to simplify the design of the coupling compared to the base case
Keywords: the coefficient gain, a separate positive connection, the coefficient of friction, clutch, friction pair
Principle of operation of a Turing machine and its variations, including finite automata, is to read the data tape; such an organization is a direct analogy with the coding information biopolimers, wich in turm served as the basis for the creation of several DNA-based computers. Computer input device in the form of O-DNA created before, however, the input and output demanded difficult reactions, each of which require human supervision.
Keywords: hardware basis cascade limitations hybridization ligativny cycle, coding information, computer DNA, enzymes, molecular software
An overview of research related to the tasks of processing and filtering of signals. Signal is considered as a random process defined by probabilistic characteristics. This article addresses the issues of the history of the development of methods of signal filtering. Recent scientific publications in which the results and the main directions of research in the field of signal processing and filtering are analyzed. Presented material extends the current state of knowledge about the problem.
Keywords: signal, signal filtering, signal processing, stochastic process
The article presents the results of calculations of reinforced concrete columns of high-strength concrete on the SNiP and SP. Compared the results with experimental data. The proposed adjustment formulas used with correction factors k and w resulting standard deviation of the bearing capacity of the columns from the experimental reduced more than four times.
Keywords: high-strength concrete, physical experiment, the correction factor calculation scheme undeformed
"This review covers various methods of synthesis LaMnO3 ferroics. The general analysis of the solid-phase synthesis reactions methods and wet methods (sol-gel, sorption, co-precipitation) are carred out. The original results of LaMnO3 syntheses from various precursors by means of the in situ method are showned. The advantages and disadvantages of different methods of synthesis are determined. The analysis of synthesis LaMnO3 ferroics published data is shown:
- the structure formation of LaMnO3 in perovskite-type phases occurs at different temperatures, depending on precursors states;
- LaMnO3 perovskite phases differ in symmetry and unit cells parameters at room temperature, depending on the preparation conditions;
- the highest synthesis temperature of LaMnO3 are typical for solid phase reactions method (950-1050 ° C), the lowest - for wet synthesis methods (500-700 ° C);
- the synthesis conditions effect the stoichiometry of LaMnO3 for oxygen content.
Our studies of structure formation processes of LaMnO3 by in situ method are allowed to define the role of precursors states at synthesis of solid phase reactions methods, adsorption, co-precipitation and sol-gel mixtures.
It is determined that in samples prepared by wet chemical methods, the formation processes of LaMnO3 perovskite phases occur at lower temperatures than by solid phase reaction (sol-gel precursor - 500 <T <600 ° C; precursors obtained by coprecipitation and sorption methods - at 600 <T <700 ° C and 700 <T <800 ° C, respectively).
Keywords: ferroics, LaMnO3, X-ray diffraction, solid-phase synthesis, sol-gel synthesis, sorption, co-precipitation
Oxide bronzes MxEO3 (M–Na,K; E – W,Mo) are the inorganic materials for technics and chemical technology. Its properties, for example stability in wide interval of temperatures, are of great practical interest (electrodes for fuel elements, electronic apparatuses and others). In this article the results of studies of thermostability of sodium and potassium tungsten and molybdenum bronzes in atmosphere and vacuum condition at the temperatures range 20-1110°C were found. The samples are prepared by electrolysis of melts of sodium and potassium isopolytungstates and molybdates. Dates for bronzes Na0.92WO3 , Na0.68WO3 , Na0.53WO3 , Na0.15MoO3, K0.3MoO3 were characterized by the termogravimetric-differential- thermal analysis (TG-DTA). Regions of stability of Na0.92WO3 : 20-700°C , of MxMoO3 : 300-500°C were founded. Conclusion about correlation of nonstoichiometry of chemical composition of EOx bronzes and oxides, which making important role in formation of less - common metal bronzes structure.
Keywords: oxide alkali bronzes, tungsten, molybdenum, thermostability, nonstoichiometry, thermal analysis
We solved the problem of optimization of thick-walled prestressed concrete cylinder loaded by internal pressure. Preliminary stresses in such a cylinder are created by wounding with tension cables on the outer surface. The idea of the method is to find the law of variation of modulus of elasticity , in which the state of stress is given . The analytical dependence of modulus of elasticity of the radius at which the tensile stress in the entire thickness of the shell does not occure was found. By creation of indirect heterogeneity we reduced the consumption of rebar by 10%. The direct problem - determining the stress- strain state of a cylinder with a constant modulus of elasticity was also resolved.
Keywords: thick-walled prestressed concrete cylinder, optimization, inverse problem, theory of elasticity, heterogeneity
An approach to the calculation of the optimal values of the protective layer of longitudinally reinforced concrete columns, operating at a central compression. Modeling performed using FEM - Ansys package for the design and implementation of spatial models of flat section of the column.
Keywords: reinforced concrete column, longitudinal reinforcement, a protective layer of concrete, finite element method, critical load
The article deals with the analysis of intermittent lanes priority based on simulation. The implementation of intermittent lanes priority system is only possible within the framework of urban intelligent transportation system (ITS). In some cases, there are not always enough ITS components for the operation of intermittent lanes priority system. Based on the simulation it is possible to determine the efficiency of the intermittent lanes priority system with the minimum or complete number ITS components. To compare the effectiveness of intermittent lanes priority system the simulation was performed for the four scenarios:
1. Without the use of public transport priority
2. Classically marked priority lane
3. Using the intermittent lanes priority system with a minimum number of ITS components
4. Using the intermittent lanes priority system with the full amount of ITS components
According the results of simulation we concluded that the minimal intermittent lanes priority system is noticeably inferior to a fully functional intermittent lanes priority system on the effectiveness, but such system does not require a high level of development of the urban ITS and can be considered as the first stage of a complete intermittent lanes priority system.
Keywords: the organization of the bus lane priority, priority lane, intermittent bus lane priority, road capacity, controlled road signs, intelligent transportation system