The article presents the quality assessment of repair work for electricity pilons of transmission line performed by the method of vibration diagnostics. The suggested criterion for assessing the quality of the repair is relative adhesion of repair layers to the base of the stand. Modeling of structural oscillations strut mount, transmission lines and calculations in the finite-element complex Ansys. The dependence of the parameters own frequency of fluctuations of the value of damage at different values of the space adhesion. The resulting equations based on changes in natural frequencies on the magnitude of adhesion. The calculation of the relative adhesion of the repair composition to the concrete model of the design. The material presented can be used for assessing the quality of repair work of different structures of the core type reinforced concrete structures.
Keywords: vibration diagnostics, quality, repair of structures, defect, adhesion, natural frequencies
Expediency of creating a method of complex estimation of investment projects in construction is substantiated in the article. The necessity of the accounting internal and external factors, their importance and trends, and also an inertance of manifestation factors are proved. The method is recommended to use for complex estimation of created and already realized investment projects in construction.
Keywords: investment project, complex estimation, efficiency, multicriteria optimization, fuzzy logic, construction
Thermoresistors nowadays are used not only as parts of temperature sensors and flowmeters but they are used as components of starting and control devices. Use of low-powered thermoresistors as starting and control devices parts needs a lot of devices that reduces equipment reliability. Current step-up running through motor-starting devices simplifies control circuit. For using thermoresistors in electric circuits with high-discharge rate it is necessary to use special constructions in order not to let termoresistor body be overheated. Thermoresistor expansion results in changing of thermal fields distribution pattern inside this semiconductor. The authors show calculated characteristics which let determine proportions and shapes of semiconductor subject to thermoresistor temperature.
Keywords: high power thermoresistors, thermoresistors of coaxial type, current density, temperature, analogy criterion, thermal conductance, temperature gradient, thermal field, stability criterion
One of the most important elements of the bridge, from which the service life of this structure directly depends, is the supporting part. It provides the movement and rotation of span structures, as well as the transfer of all loads from the forces acting on them to the supports. The task of the designer is to select such support parts, that could be allowed maximum reducing of the forces, acting at the ends of the beams and having a minimum resistance to their free movement. It is necessary in each case to select the support part, which will most closely meet the requirements. To solve this problem, the author structured and tabulated the kinds of support parts. And also an analysis of the main characteristics of some of them.
Keywords: bearing part, exothermia, bridge structure, durability, service life, transfer of loads and displacements, deforming systems, sliding systems, rolling systems
Created single-stage model of silicon solar cell using PC1D v.5.9 program, designed to simulate the photovoltaic devices. In the process of simulation change the level of doping and thickness of the n + type layer of the front, as well as applied texturing the front surface. The influence of the doping level and the thickness of the n + type layer in the photovoltaic solar cell characteristics. It was determined that with the increase of the doping level and the thickness of the front n + -layer a decrease in the efficiency of solar cells. It was found that the use of texturing the front surface leads to an increase in efficiency and is associated with reduced reflection losses and an increase in the photocurrent.
Keywords: Silicon solar cell thickness, doping levels, texturing, current-voltage characteristic
It describes the importance of urban development in national security, which is caused by the development of the defense infrastructure districts.
Keywords: city garrison, armed forces, defense, defense infrastructure
construction, road, system IndorCAD/Road, a digital model of geodetic engineering terms, design, transport system, transportation hub.
Keywords: construction, road, system IndorCAD/Road, a digital model of geodetic engineering terms, design, transport system, transportation hub
Currently, laser annealing are widely used to create a polycrystalline silicon film, which is promising for use in thin film solar cell, and transistors, liquid crystal displays and sensors due to recrystallization of amorphous and nanocrystalline silicon films. The study of morphology and surface conductivity of single-crystal silicon film on a glass substrate by laser annealing power. Laser annealing is carried Nd: YAG laser with a wavelength of 532 nm, speed of movement of the stage with a specimen of 5 mm/s and a laser power ranging from 34 to 86 watts. The laser beam was focused on the sample in the form of a narrow line width of 10 microns and 60 mm in length. The dependence of the size of the nanocrystals and the conductivity of silicon films on the power of the laser annealing radiation. It is shown that the power of the laser radiation in the range of 60 to 70 W is optimal for the best electrical parameters silicon film for the purpose of its use in high-performance thin-film solar cells.
Keywords: silicon film, laser annealing, surface morphology, electrical conductivity, thin film solar cell
The calculation of multi-storey reinforced concrete frame building, consisting of apartments, offices and underground parking, against progressive collapse is presented in the paper. Two different ways of simulation of reinforced concrete building against progressive collapse are suggested, needed for estimation of survivability of building structures. The technique, which allows to carry out the stability of reinforced concrete structure to resist progressive collapse, is presented. This method is based on a nonlinear analysis of framed structures under the special load combination and includes dead and live loads, implying that the loading process modeling is fulfilled on the basis of the adjusted step method. The last one is of great importance for simulation of the processes in the whole life cycle of structures. The obtained results show that the offered strength calculation method of the framed structure against progressive collapse considers both geometric and material nonlinearity and also allows to assess survivability of the construction under conditions of emergency events and its stability to resist against progressive collapse. The step method of solving nonlinear problems, applied for modeling of collapse process, is shown to be more appropriate for these cases. We conclude that applying the proposed method of calculation results in more economic use of materials, giving evidence of its effectiveness.
Keywords: progressive collapse, survivability of building structures, computer simulation, structural elements, nonlinear analysis, stability, geometric and material nonlinearity, the step method
A numerical model of the laser annealing TiO2 film on the TCO / glass substrate with radiation of a wavelength of 1064nm (Nd: YAG laser) to the crystallization and its use in solar cells perovskite. The modeling used a numerical finite difference method for solving a system of one-dimensional unsteady heat conduction differential equations. As a result, laser annealing temperature distribution obtained in the process of modeling the structure of TiO2 / TCO / glass substrate by varying the laser power. It is shown that a high laser power (30-100 watts) is enough for an effective transition organometallic precursor of TiO2 in the crystalline phase of anatase TiO2 (transition temperature of 400-600 °C) for a short period of time (60 sec.) due to the direct absorption of photons laser radiation. It is found that for experimental studies should be used laser power of 30-70 watts, since a higher power (e.g., 100 W) raises the temperature of the substrate above its melting point (for example, for glass 650 ° C).
Keywords: Numerical modeling, laser annealing, TiO2 film, heat equation, solar cell
The article presents the algorithm of repair work for electricity pilons of transmission line.The technical diagnostics based on complex method includes a visual inspection, instrumental and vibration diagnostics for electricity pilons of transmission lines. Pilons has defects: inclined cracked faces with a length of 25-30 cm , with a crack width of 0,4-0,7 mm . Were selected effective repair compositions for restoring reinforced concrete structures rack transmission towers:modified fine-grained concrete, polymer concrete. The article presents an example of analytical modeling of natural vibrations of a reinforced concrete pilons of transmission lines with defects in the base. This article contains a list of repair works. The material presented can be used in the development of methods of diagnostics and monitoring of technical condition of different structures of the core type.
Keywords: Algorithm, repair, category of defects, non-destructive testing methods, pilons of transmission lines, vibrodiagnostics
The market in Russia is common formwork caisson ceilings SkyDome system.In the article the question of the effectiveness of ribbed caisson ceilings in multi-storey monolithic buildings compared to with .flat slab floor. The program complex "Lira-CAD 2013" calculated the 18-storey residential buildings with monolithic framework. Consider in detail the reinforcement floors typical floor in two versions: a flat of 200 mm and a caisson plate of 50 mm and beams with a section of 200х350 mm with a step of 900х900 mm. Analysis of the results showed that in a building with columns a step of about 5 m difference in cost of materials for the manufacture of the overlap was about 1%. Efficiency gains are expected by increasing the span up to 8 ... 10 m
Keywords: caisson, flat slab floor,monolithic framework, modular falsework of SkyDome, structural calculation, LIRA-CAD
Family is the most important actor in cultivating values of trust in the youth environment, however, the effectiveness of implementing this feature of the Russian family is limited to the trends occurring on the macro level and marked by a lack of trust in society, both at the macro and micro levels. Very clearly a crisis of confidence manifests itself in the urban environment of Russian society. Eventually, trust transforms into a family value that identifies the microcosm of the family interactions. The reality of the external world to the world of the family, urban youth perceive as socially unjust and full of distrust, determines, in the end, and the low trust rating in the system of values of young Russians.
Keywords: family, trust, youth, urban youth, urban environment, values, social justice, Russian society
The paper describes and analyzes the main development trends of Russian forestry machine-building in modern conditions. Russian forestry machine-building enterprises do not use presently available perspectives in import substitution in connection with the depreciation of the rouble. Neither do they use the opportunities for producing integrated multifunctional machines. Development and production release of forestry machines for assortment harvesting based on Russian-manufactured tractors fitted with technological equipment of foreign manufacture is the first step on the way of creating domestic vehicles of analogous purpose. These machines will be fully complete with home-produced technological equipment. This will allow reducing the costs on the production of these machines and on their timber-harvesting operations
Keywords: forest harvesting technology, felling, limbing, cutting into lengths, skidding, forestry machine-building, development
This article is considered Immunological method of the railway vehicle's parts localization based on the clonal selection algorithm. The advantage of this approach is the use of one-class support vector machine, which allows classifier training with only positive examples. The suggested approach significantly reduces complexity and formation of the training sample set. Immunological localization method has high performance characteristics due to the hybrid application one-class support vector machine and clonal selection algorithm. This allows to optimize the procedure of objects finding in the analyzed image
Keywords: Immunological localization method, clonal selection algorithm, one-class support vector machine