bluuebunny/crossref_metadata_2025 huggingface dataset:
Application of atmospheric correction in the measurement of land displacements using the PSInSAR technique, on the example of the Tahmoor mining region, Australia
Authors: Kopeć Anna
Published: December 2018

InSAR (Interferometric Synthetic Aperture Radar) techniques are a very good tool for identification and observation of surface area displacements. Achieved accuracy of several centimeters, still do not allow for the quantitative analysis of the observed movements. Due to the high dynamics of phenomena in the Earth's atmosphere, one of the biggest limitations of InSAR are disturbances caused by changes in the atmosphere, between two measurements, on the basis of which an interferogram is created. In order to reduce the impact of the atmosphere on the SAR signal course, an atmospheric correction is applied.This study presents the results of calculations using the PSInSAR technique for the Tahmoor mining area located in south-eastern Australia, from 2006-2010. The atmospheric correction was determined: in an empirical way - on the basis of a linear relation between the signal phase and the topography of the area, based on data from the ERA - Interim weather model and data from the MERIS spectrometer.
A modeling analysis of grounding resistance and sea surface potential on the jacket foundation offshore wind turbines
Authors: Tao Shiqi , Zhang Xiaoqing , Wang Yaowu
Published: December 2018

Offshore wind turbines (WTs) are frequently exposed to the risk from lightning, storm, and waves. As a kind of fixed foundations, jacket foundation can effectively reduce the correlatively risk and loss. In order to provide more information about the lightning protection of jacket foundation, a simulation model has been built by simplifying the hollow steel tubes into a series of solid steel cylinders. And some conclusions on the grounding resistance of jacket foundation have been summarized in this paper by using the GSSAS (Grounding System Safe Analysis Software). According to the simulation results, the actual influential factors of grounding resistance, including the depth of seawater, the thickness of clay layer and the resistivity of gravel layer, have been analysed and compared. It is found that the grounding resistance is influenced most severely by the depth of seawater. In addition, the values of sea surface potential have been calculated by the software GSSAS and the three-dimensional diagrams of potential distribution have been mapped out.
Excellent Luminous Efficacy and Color Homogeneity of White Light-Emitting Diodes with YPO4:Ce3+:Tb3+ Phosphor
Authors: Thoai Vo Phu , Anh Nguyen Doan Quoc
Published: December 2018

In this paper, we focus on researching the method, which the color homogeneity and the lumen output of multi-chip white LED lamps (MCW-LEDs) need to support for increasing the efficiency. The successful results can be achieved by mixing the green YPO4:Ce3+:Tb3+ phosphor with their phosphor compounding. Through experiment results, we assert that the MCW-LEDs can achieve the significant consequence in performance by following that method and it is also again confirmed that when the concentration of YPO4:Ce3+:Tb3+ has tendency to increase, which impulse the development of the color uniformity and the luminous efficacy of MCW-LEDs with average correlated color temperatures (CCT) of 8500 K, while the color quality scale shows signs of gradual decline. It is not difficult to gain incredible presentation of MCW-LEDs if we are clever in choosing the suitable concentration and size of YPO4:Ce3+:Tb3+.
Estimation of Vertical Jump Height Using Nintendo Wii Remote IR Camera
Authors: Klongratog Bhanupol , Pengto Warit , Wornkert Todsaporn , Srongprapa Anupong
Published: December 2018

In this article, we proposed to measure the heights of countermovement jumps which are recorded in term of vertical leap by using the Wii Remote infrared camera. According to the physical principles, positions of the movement were detected based on the rules regarding conservation of energy, motion under gravity, and coordinate system. The obtained results were compared with that of the slow-motion measurements. The experiment involved 30 basketball players whose jump results were slightly deviated from the vertical measurement of the coordinate system. Therefore, the results should be calibrated each time the new system is installed.
Estimation of Carbon Emissions of Domestic Energy Usage by Chinese Residents Based on Input - Output Method
Authors: Sheng Zhonglin , Gu Kan , He Weida
Published: December 2018

This paper will be based on the existing literature and research methods, with the 1980 to 2014 China’s residential carbon emissions estimates. This paper mainly examines the changes in total residential carbon emissions and per capita carbon emissions, energy consumption per unit of household energy consumption, carbon emissions and energy composition of the above-mentioned analysis of urban and rural compared with the international comparison.
Calculation of temperature field of coiled wire using EFM
Authors: Shu Zhongjun , Shen Wei , Li Qiang , Fan Minghao , Zhang Jiaqing
Published: December 2018

Provided a heat transfer model of coiled wire method. Based on the method, a software of EFM (ANSYS) was used to calculate the temperature field of coiled wire. Comparisons between the experimental of RVS coiled wire and numerical results indicated the effectiveness of the method utilized. The simulation method based on EFM proved to be useful for the fire risk assessment of coiled wire.
Technology and electrophysical properties of Mn4+, Sb3+, Dy3+ and W6+ -doped Pb(Zr0.49Ti0.51)O3 ceramics
Authors: Bochenek Dariusz , Ewa Ćwikiel , Niemiec Przemysław , Goryczka Tomasz
Published: December 2018

In paper three multicomponent PZT-type ceramics doped by Mn4+, Sb3+, Dy3+, W6+ have been prepared by the conventional mixed oxide method. The multicomponent PZT-type ceramic powders were synthetized by calcining route, while densification was carried out by pressureless sintering method. The paper presents XRD, SEM, EDS, dielectric and DC electric conductivity measurements of the multicomponent PZT-type ceramic samples. Conducted tests indicate obtained multicomponent PZT-type exhibit good dielectric properties giving the possibility for their use as actuators and piezoelectric transducers in modern micromechatronic and microelectronic applications.
The effects of the heat treatment on the microstructure of Inconel 625/steel bimetal joint obtained by explosive welding
Authors: Kosturek R. , Wachowski M. , Śnieżek L. , Gloc M. , Sobczak U.
Published: December 2018

In this investigation steel P355NH was successfully clad with Inconel 625 through the method of explosive welding. Explosively welded bimetal was subjected to the two separated heat treatment processes: stress relief annealing (at 620oC for 90 minutes) and normalizing (at 910oC for 30 minutes). In order to identify the microstructure of the joint and to investigate the influence of the heat treatment on it, the light and scanning electron microscope observations and microhardness analysis have been performed. In order to investigate the diffusion zone microstructure the scanning transmission electron microscope observation have been performed. It was stated that obtained joint has characteristic wavy-shape geometry with the presence of the melted zones and severe deformed grains of both joined materials. Strengthening of materials in joint zone was established with microhardness analysis. In both of the heat treatments the changes in the grain structure have been observed. The normalizing heat treatment has the most significant impact on the microstructure of the joint as well as the concentration of the chemical elements in the joint zone. It was reported that due to normalizing the diffusion zone has been formed together with precipitates in the joint zone.
Analysis of crack mechanism in FGH 98 superalloy during the laser solid forming process
Authors: Ying Weisheng , Fan Shukai , Han Fuzhu , Wang Junhua
Published: December 2018

In this study, FGH 98 superalloy parts were fabricated by laser solid forming (LSF) and the microstructure and defects of the LSF part were revealed using optical microscope and scanning electron microscope. It was found that the main defect in the LSF part was cracks. In order to analyze the phase transition process and crack mechanism, the temperature and stress fields were simulated. Based on the simulated result, Ni-Al phase diagram and morphologies of cracks, it can be concluded that the micro segregation caused by the rapid heating and cooling rates was the main reason for the crack defect.
Design and Simulation Analysis of Micro-Porous Structure in Infiltration-Type Self-Lubrication Composites Matrix
Authors: Ying Han
Published: December 2018

Metal ceramic preforms were fabricated by vacuum sintering method in this work. Ti–Fe–Cr–W–Mo–V powder was used as the basic material, TiH2 and CaCO3 were used as the composite pore-forming material and Al2O3 was used as dispersal particles. The microstructure and the worn surface morphology of the preforms and the composites were analyzed using scanning electron microscope (SEM) and energy dispersive spectrometer (EDS). The experimental results showed that when the micro-pore shapes are circular and quadrilateral respectively, with the increasing load, the Mises equivalent stress distribution generated by the single cell model is quite different, but it has symmetry, and the maximum stress appears around the interpenetrating micro-pore. Using FeCrWMoV alloy powder as the metal phase and TiC powder as the ceramic phase, the micro-porous matrix was prepared by powder metallurgy sintering with the addition of a certain volume fraction of compound pore-making agent.
Temperature-programmed surface reactions of methanol and dimethyl ether on bifunctional catalysts for the direct synthesis of dimethyl ether from syngas
Authors: Vodorezova Olga , Musich Pavel , Karakchieva Natalia , Heinrich Lothar , Kurzina Irina
Published: December 2018

Dimethyl ether (DME) can be used as a replacement for diesel fuel in transportation. The catalytic effectiveness of bifunctional catalysts for DME one-stage synthesis from carbon monoxide and hydrogen was estimated in the paper. Bifunctional catalysts CuZnAl/HZSM-5, CuZnAlCr/HZSM-5, and CuZnAlZr/HZSM-5 were obtained by physical mixing of CuZnAl(Cr/Zr)– Ох and HZSM-5 components and were characterized by BET, X-ray diffraction, and temperatureprogrammed surface reaction methods. Based on the TPSR results, the mechanism of the interaction of methanol and DME with the surface of the bifunctional catalyst was studied. It was found that the temperature range of the greatest catalytic activity was 240–260 °С.
Pyrotechnic heater setup as a calorimeter: Micro- vs. nano- Mg/Fe2O3 thermites
Authors: Monogarov Konstantin , Muravyev Nikita , Meerov Dmitry , Dilhan Denis , Pivkina Alla
Published: December 2018

Combustion of thermite composition Mg/Fe2O3 with micron- and nano-sized components was studied in pyrotechnic heater setup. Pressed charges were burned out in hermetic steel tubes with simultaneous pressure and temperature registration. Advanced system of thermocouples connections allows drawing thermal maps of the steel case heating with high spatial and temporal resolution. Mathematical processing of raw thermal data gives the temperatures for thermite combustion. Initial temperature and setup orientation (either vertical or horizontal) show almost no influence on combustion temperature. Nanothermite produces in 500 K lower temperatures compared to micron-sized composition, apparently due to lower metal content in nano-Mg. Comparison of the experimental data with thermodynamic calculation output shows important differences in the combustion temperature and composition of products. Adiabatic temperature predicted is slightly lower than experimental and this fact is linked with formation of spinel MgFe2O4 phase, not accounted in computations. Thus, utilization of the pyrotechnic heater setup gives valuable information not only about pressure and porosity effects, but also about combustion temperature, composition of products and process mechanism.
Highly soluble cellulose nitrates from unconventional feedstocks
Authors: Gismatulina Yulia , Korchagina Anna , Budaeva Vera , Sakovich Gennady
Published: December 2018

Celluloses isolated by the nitric-acid process from domestic unconventional feedstocks such as Miscanthus, oat hulls, and intermediate flax straw were used herein to produce cellulose nitrates (CNs) with a high solubility. For the synthesis of CNs, a commercial technique was employed that involves nitration of cellulose with mixed acid containing 14 wt.% water followed by high-temperature treatment of the nitration product in acidic, alkaline, and neutral environments. The obtained CNs are similar in physicochemical attributes: 12.04–12.26% mass fraction of nitrogen, 10–14 mPa·s viscosity, and 98% solubility in alcohol– ester mixture. FTIR spectra of CNs had absorption bands (2559–2557, 1646–1631, 1277–1271, 825–812, 747–744, 683–680 cm-1) typical of nitro group vibrations. 13C NMR spectra showed chemical shifts representative of 6-mononitrocellulose, 2,6-dinitrocellulose, 3,6-dinitrocellulose, and 2,3,6-trinitrocellulose. DSC revealed that the resultant CNs were highly chemically pure with an exothermic peak at 209–212°С. The CNs obtained from the said unconventional feedstocks were compared with a commercial, highviscosity, lacquer-grade Colloxylin derived from cotton cellulose, as well as with other commercial Colloxylins, to show that the experimental CNs meet the requirements for comercial grades. Thus, the CNs obtained from the unconventional feedstocks are promising candidates as the component of composite explosives.
Effect of dispersity of powder system Al-Mg-B on the phase composition of sintered ceramics AlMgB14
Authors: Nikitin Pavel , Zhukov Ilya , Vorozhtsov Alexander , Zhukov Alexander , Dubkova Yana
Published: December 2018

In work studies of materials obtained from various powder mixtures Al-Mg-B after mechanical processing in a planetary mill and subsequent vacuum sintering were carry out. It was found that for each mixture exists optimal time of mechanical treatment in a planetary mill, at which the maximum content of AlMgB14-phase is reached. It was shown that for the samples synthesized from the Al-Mg-B powder mixture with the dispersion of the raw aluminium powder ~80 μm after 5 hours of mechanical activation and subsequent vacuum sintering at a temperature of 1130 °C, the maximum phase of AlMgB14 is ~ 85-90 wt.%.
Method for experimental data processing in the sphere of hydrodynamics of packed heat and mass exchange apparatuses
Authors: Merentsov Nikolay , Balashov Vyacheslav , Bunin Denis , Lebedev Vitaliy , Persidskiy Aleksandr , Topilin Mikhail
Published: December 2018

The article dwells on the method for summarizing experimental data on hydrodynamics of one-phase filtration flows through packed heat-and-mass exchange apparatuses differing in configuration. Summarizing is performed using a modified generalized equation. The described method simplifies the work with experimental bulk data, helps to compare the packed heat-and-mass exchange apparatuses, assess their energy performance and find the ways for their industrial implementation in heat-and mass exchange equipment.
New fusible binder additives for composite explosives
Authors: Komarova Marina , Vakutin Aleksey , Kozyrev Nikolai , Sukhanov Gennady , Il’yasov Sergey
Published: December 2018

Occupational safety in manufacturing powerful melt-cast composite explosives requires replacement of conventional fusible binders, as trotyl and dinitrazapentane, by less sensitive compounds. To solve this challenge, insensitive 3-nitro-1,2,4-triazole derivatives (1-, 2-methyl, tert-butyl, ethoxymethyl) and their eutectic mixtures with furazanyl furoxane can be used in formulations with 1,3,5,7-tetranitro- 1,3,5,7-tetrazocane (octogen, HMX) and 6-nitrohexaazaisowurtzitane (CL-20). Our studies shows quite low sensitivity impact of the nitrotriazole derivatives (≥ 500 mm at a load weight of 10 kg), their melting temperatures (56…94 °С), and their eutectic temperatures with furazanyl furoxane (57…62 °С). For HMXbased composite explosives, the optimum options are ethoxymethyl-3-nitro-1,2,4-triazole and its eutectic melt with furazanyl furoxane (80/20 weight ratio), while for CL-20-based formulations, the appropriate additives were 1-methyl-3-nitro-1,2,4-triazole and its eutectic melt with furazanyl furoxane (80/20 weight ratio). Phase diagrams of the new fusible binder additives are also given. The data were obtained by differential scanning calorimetry(DSC).
Stress-strain state of a composite near rectangular inclusion
Authors: Pisarev Pavel , Anoshkin Aleksandr , Ashihmin Vladislav
Published: December 2018

In this research we developed a technique for calculating the stress-strain state of a model construction from a thermoplastic composite material with an embedded piezoactuator. Numerical simulations of the model construction stress-strain state with different arrangement of piezoactuators: upper and middle,-were performed. Numerical simulations were carried out in a three-dimensional setting taking into account the complete technological scheme of laying and anisotropy of the properties of reinforcing layers. The results of numerical experiments revealed the areas of maximum stress. Recommendations for the MFC’s embedding into composite materials were formulated.
Structure and mechanical properties of A356-C alloys
Authors: Khmeleva Marina , Khrustalev Anton , Vorozhtsov Alexander
Published: December 2018

The paper deals with influence of mechanical mixing and vibration treatment on the structure and mechanical characteristics of the aluminum alloy containing ≤ 1 wt.% of nanodiamonds (A356-C). The alloy was obtained from industrial A356 Al-Si casting alloy by means of an integrated effect of mechanical mixing and vibration. It has been shown that the introduction of nanodiamond particles contributes to improving the alloy structure and increasing its mechanical tensile properties. The structure of the A356 aluminum alloy has been refined with introduction of 0.2 wt% nanodiamonds and application of vibration melt treatment. The introduction of nanodiamonds into the melt and the vibration melt treatment enable one to increase the yield strength and tensile strength of the A356 aluminum alloy without any change in ductility.
The study of the behaviour of the ceramic composites ZrO2(MgO)-Al2O3 in a wide temperature range
Authors: Korobenkov Maxim , Kulkov Sergey , Leitsin Vladimir , Tovpinets Alexander
Published: December 2018

The paper presents the results of experimental studies of the temperature dependence of the strength characteristics of porous ceramic composites. It is known that the most significant factors affecting the mechanical characteristics of brittle ceramic composites are the pore structure parameters. Increase of porosity leads to decrease of strength characteristics of ceramic composites, however researches about mutual influence of porosity and temperature of tests on strength characteristics were not carried out. The results of studies to determine the strength characteristics of composites under compression showed that the increase in test temperature led to a decrease in compressive strength for specified types of composite porosity by an average of 10%. Experiments carried out at negative temperatures have shown that samples with a porosity of 21% have the greatest strength sensitivity to temperature test conditions.
Detonation propagation along percolating cluster in composite explosives
Authors: Komarov Vitaly , Sakovich Gennady , Popok Nikolai , Kazutin Maxim , Kozyrev Nikolai
Published: December 2018

The detonation performance of melt-cast plastic-bonded explosives (PBXs) based on high melting explosive octogen (HMX) was studied in the paper. It has been found that the detonation velocity strongly depends from the dispersion distribution of HMX particles: it changes from 7800 to 8700 m/s. We explain this by the possibility of detonation propagation in PBX through different mechanisms, including detonation front propagation along a percolating cluster formed by filler particles. Thus, varying the particle size distribution can bring about one detonation mechanism or another and hence control the energy release dynamics of melt-cast PBXs to attain high efficiency in practice. Experimental results confirm the assumptions.
Welding materials used to increase service life of agricultural machinery processing soil
Authors: Hrabě Petr , Kolář Viktor , Kabutey Abraham , Sedláček Aleš
Published: December 2018

Intensive abrasive wear occurs in soil-treatment machines. This article is focused on increasing the service life of ploughs by the welding material. The welding material is applied at a 45° angle to the tool. This material is abrasive wear resistant. The welding material was applied parallel to the head of ploughshares with spacing of 60 mm. Carbide materials were used (SK 258 TiC-O, SK 900-O, SK A43-O, SK 299- O, SK A45-O, OK TUBRODUR 15.82, SK 258 TiC-O). The tested ploughshare variants were wearing the same when were used the welding material and the standard.
Optimization and design of the vulcanization press sandwich pressure plate parameters
Authors: Vaško Milan , Handrik Marián , Kopas Peter , Leitner Bohuš
Published: December 2018

The goal of this paper is to present the optimization of the vulcanization compactor pressure plate construction design. The basic factor for the mechanism functionality is the required stiffness compliance. The total construction stiffness has an influence on the vulcanization form tightness. Several solutions of the pressure plate have been proposed in the initial phase. Each proposal has been optimized in order to minimize the pressure plate weight meeting the conditions of the maximum displacement and the maximum allowed stress. The best solution has been chosen on the base of the evaluation afterwards. The multisoftware approach using ADINA and MATLAB software was used to perform FE analyzes.
Application possibilities of the low-temperature repairs on creep-resistance turbine components from material GX23CrMoV12-1
Authors: Moravec Jaromir , Novakova Iva , Sobotka Jiri , Kik Tomasz
Published: December 2018

Papers deals with the problems of repairs at new and also already loaded components of steam and gas turbines. Generally, it is about welding repairs at valve and turbine chambers, transmitters, vane carriers, tripping valve body and so on. There are both technological defects caused by casting (e.g. shrinkage cavities, misruns, porosity and cracks) and defects caused by operation (thermal-stress fatigue, incorrect method of operation, etc.). Many of the mentioned defects take effect not until the final technological method - mostly at machining. However, in this production phase it is not possible to get form the supplier new production elements due to economical and also delivery time reasons. All of that results in delay of production and penalty. As the major aim of this paper, there was to find such repairs techniques which can ensure serviceability of mentioned devices under the standard regime. In these cases is needed to use much lower tempering temperature than under the standard production, mainly because of necessity to eliminate deformation caused by heating of part that is not possible to be subsequently removed by machining.
Influence of roller - burnishing on surface roughness parameters and roundness
Authors: Görög Augustín , Görögová Ingrid , Stančeková Dana , Janota Miroslav
Published: December 2018

In order to increase productivity, machining times and market competitiveness of machining production systems, it is important to continuously develop existing technological solutions. The paper deals with surface roughness and roundness after roller burnishing outer rotary surface. Roller burnishing was applied on turned surfaces with different surface roughness. Each outer rotary surface was roller burnished twice with the same conditions (pressing force, peripheral speed of machine part, feed of tool). The parameters of the surface roughness Ra, Rq and Rt were measured after each single roller burnishing. The results show that the surface roughness is decreasing after the first roller burnishing cycle (additional roller burnishing had only negligible influence on surface roughness) and the original surface roughness has a significant influence on change of surface roughness after roller burnishing.
Analysis of roughness profile on curved surfaces
Authors: Drbúl Mário , Martikáň Pavol , Bronček Jozef , Litvaj Ivan , Svobodová Jaroslava
Published: December 2018

Production and control of accurate surface bring some issues. There are some technological limits of machining, but we have to know how to control these machined surfaces due to functional and life-time properties, which are affected mainly by roughness surface. Most important part of system of roughness surface measuring is suppression of nominal shape of scanned profile, its filtration according to standard ISO 4288 and evaluation according to the relevant standards. This article described process of filtration of roughness surface profile. If operator of the measuring instrument omits some important aspects at this stage, we obtain incorrect roughness surface profile, which significantly distorts the results of measurement leading to a rough error. The article is aimed at verifying roughness meters and indicates if a certain amount of data would be lost as if this loss affected the measurement result. Objectively, such a loss of data was simulated in the evaluation by considering every 7th scanned point at constant velocity of measurement.
The mould for production of plastic spout cap with internal thread by injection moulding
Authors: Bulej Vladimír , Čuboňová Nadežda , Eberth Manfred , Vasilko Karol
Published: December 2018

The main aim of this article is the mould design for production of plastic spout cap with inner thread by injection moulding technology. There are described the basic steps of whole design process with respect to fulfil all technology and functionality requirements. The application of hot runner system as well as hybrid ejection system based on rotary cores and stripper plate can be considered as the main innovative features of the designed mould. The mould flow analysis was carried out for the functionality demonstration.
Possibilities of applying motif group parameters for description roughness of turned surfaces
Authors: Kowalski Maciej , Wiśniewska Magdalena , Karolczak Paweł , Holubjak Jozef
Published: December 2018

This article explores the methodology of assessing the applicability of roughness parameters from the motif group to the evaluation of one-way and periodic geometrical surface structures. The results of surface roughness measurements of aluminum samples turned with variable kinematic parameters were presented. Usability of using surface motifs in combination with selected parameters described in ISO standards for assessment of geometrical structures characteristic for longitudinal turning was shown.
Research on water jet cutting of composites based on epoxy/microparticles from coconut shell
Authors: Müller Miroslav , Valášek Petr , Linda Miloslav , Kolář Viktor
Published: December 2018

The paper deals with a machining of polymeric composite materials with a reinforcement based on a waste from a coconut processing, i.e. a coconut shell by means of an unconventional technology, i.e. a water jet (WJ). These composite systems are desirable in the material engineering. Not only the research of their subsequent mechanical properties is important, but also searching for effective ways of machining and dividing to required shape and size. The composite material was tested in a form of boards made by means of a vacuum infusion. The aim of the research is to study an influence of the abrasive water jet and water jet at its impact on a surface of the machined polymeric composite material. The research was proved on CNC cutting machine AWJ CT 0806. Cutting conditions, i.e. various traverse speeds 50, 100, 250, 500, 750 and 1000 mm/min, an influence of cutting by the water jet with abrasive particles and without them on an integrity of the tested material and the surface topography were evaluated within the research. A surface analysis is also evaluated by means of a scanning electron microscopy (SEM) depending on a traverse speed and a mass flow of the abrasive grains.
Analysis of the market of electric tractors in agricultural production
Authors: Caban Jacek , Vrabel Jan , Šarkan Branislav , Zarajczyk Janusz , Marczuk Andrzej
Published: December 2018

In Poland, the market of electric field tractors is practically non-existent. There are individual models in offers dedicated to the agriculture made by foreign producers. However, these offers are presented mainly at agricultural fairs. The article presents the research on the needs of farms for electric tractors and presents the possibilities of developing electro mobility in this sector of the economy. Questionnaire was presented, data were collected from those working in the agricultural sector. The data will be used to gauge attitudes and opinions towards alternative power systems implemented in agriculture.
Influence of masonry adhesion on mechanical performance of arches-walls
Authors: Bespalov Vladimir , Semenova Marina
Published: December 2018

The combine behavior of masonry arches and walls, which exert an unloading effect on the bearing arches, was analyzed. The finite-element model of the Wallen-Delamot arch was designed for the effect of the load of the overlying masonry. The load action was taken into account both from a combined finite element model with a rigid connection of the arch and overlying masonry, and from the gravitational load transferred to the arch. The dependences of the maximum acting stresses in the arch on the modulus of elasticity of the overlying masonry are constructed, reflecting the behavior of the damaged masonry, which lost rigidity properties. It is shown that when the modulus of elasticity decreases, significant changes occur in the stress-strain state of the entire structure. The obtained results demonstrate that when the arch is loaded with a gravitational load and there are no restrictions on the overlying laying of vertical and horizontal displacements, the stressed state of the arch differs significantly from its state when modeling the entire structure.
The estimation of formaldehyde concentration in indoor air
Authors: Meshalkina Marina , Sushnikov Viktor , Kryzhova Nadezhda
Published: December 2018

This article is devoted to the measurement of formaldehyde emissions from furniture materials in the classes of St. Petersburg Polytechnic University and kindergartens. An important task of society is to preserve the health of children and students, since they spend a large amount of time in public buildings. The safety of indoor air depends from the materials of which the finishing materials and furniture are made. Formaldehyde is a priority hazardous substance released into the air of confined spaces. Studies were conducted not only for the amount of formaldehyde in the air in the room, but also for the materials from which the furniture was made. Small-sized installation was made for sampling formaldehyde emissions from furniture materials. These emissions were investigated by the photometric method with acetyl acetone reagent. The installation can be used to study the emissions parameters of other components that can be separated from finishing materials and furniture.
Eventological modeling of housing and communal services system
Authors: Amelchugov Sergey , Klimov Alexey , Mickevich Oksana , Nikitina Olesya
Published: December 2018

Results of eventological [1] modeling of housing and communal services system [2, 3, 4, 5, 6, 7, 8] are looked at in examples and illustrations, which are intended to demonstrate the main features of the evaluation of activities under the circumstances of the event on the basis of a portfolio of identification features of housing and communal services; in addition, these examples and illustrations show the role and functions in the risk assessment of the three main event-related figures involved in the eventological system of housing and communal services: the total subject, the total object and the total barrier, and, most importantly, discover the key applicability of the eventological approach in the field of housing and communal services in the methods of selecting the optimal portfolio of identification features of housing and communal services, providing a given accuracy of efficiency assessment in the settlement at a given minimum expert costs.
The effect of absorption process parameters on its efficiency
Authors: Kiss Valeri , Evdokimov Aleksandr , Kaverzneva Tatiana , Tarkhov Dmitriy
Published: December 2018

In this work we are presenting the results of studies of the effect of hydro and aerodynamic parameters of the process of water vapor absorption during intensive bubbling in the dynamic foam mode on the absorption process efficiency. As a result, it was found that the hydrodynamic characteristics (height of the foam layer of the absorbent and its resistance) and aerodynamic characteristics (gas velocity, longitudinal mixing in the gas phase) have the main influence on the efficiency of the absorption process. We also investigated the effect on the efficiency of the process of kinetic characteristics, characterized by the number of transport units and absorption factor. We have proposed to estimate the overall efficiency of the process, taking into account the degree of extraction, as well as the energy characteristics (hydraulic resistance), weight and size characteristics and the drop entrainment volume. For this purpose, for the overall assessment we have proposed to introduce a conditional optimality ratio, allowing to make a comparison of both various contact devices and absorbents.
Strength characteristics of foam concrete samples with various additives
Authors: Rybakov Vladimir , Seliverstov Anatoly , Petrov Denis , Smirnov Andrei , Volkova Anna
Published: December 2018

The article presents the results of researched moisture indicators and strength characteristics of foam concrete with the various additives using. Foam concrete is produced both in a factory and on a construction site, has a density of 200 kg/m3 and is used in the innovative building structures type lightweight steel concrete structures (LSCS). Diatomite, microsilica, granite, perlite and vermiculite were used in sample production. As a part of the research, tests were carried out under the P-20 pressure to determine the ultimate limit load that the samples withstood. Then they were placed in a drying oven to determine the moisture mass removed from the samples during drying to a completely dry state, after which the moisture content values were set. The dependence between the moisture index and the strength characteristics of foam concrete is shown. It is established that samples of foam concrete with the perlite addition are the most durable. In addition, it is shown that the foam concrete with the vermiculite addition has the lowest moisture. It was determined that only for samples with the vermiculite addition, the correction coefficient depending on the moisture index differs in its value from the coefficients for the other samples, and, therefore, it had the greatest influence on the strength characteristics value of this series.
On the issue of personnel management in high-latitude construction
Authors: Amelchugov Sergei , Inzhutov Ivan , Nikitina Olesya , Berseneva Mariya
Published: December 2018

Mathematical modeling of the subject in the security system of construction in the Arctic region and the system of events characterizing the event structure of the subject are proposed. The security structure of the subject is given as an example. The practical result of the work is the possibility of a mathematical interpretation of the system of effective management of training and assessment of the combat capability of individuals and groups, taking into account their physiological, psychological state and habitat in the Arctic region.
Development of technology for production of fire-resistant nanocomposite constructional rebar and structural elements based on it
Authors: Ponomarev Andrey , Steshenko Daria , Rassokhin Aleksandr
Published: December 2018

Analysis of recent publications describing the situation with fiber-reinforced plastic rebar is contained in the paper. The available types of composite reinforcement have a number of advantages, but also have significant drawbacks. New technical developments and fresh ideas, born thanks to the integration of sciences, make it possible to begin the creation of a technology for the production of fundamentally new types of rebar based on an inorganic (mineral) binder. New rebar will be tough and resistant to fire and high temperatures.
Thermodynamic analysis of design and part-load operation of a novel waste heat recovery unit
Authors: Sebelev Aleksandr , Kirillov Aleksandr , Porshnev Gennadii , Lapshin Kirill , Laskin Aleksandr
Published: December 2018

Organic Rankine Cycle (ORC) thermodynamic optimization is of critical importance while developing new plants. Optimization procedures may be imed at the highest efficiency as well as cost or sizing minimization. Optimization process is generally carried out for plant nominal rating. At the same time, part-load operation has to be carefully considered in case of waste heat recovery from flue gases coming from internal combustion engines or gas turbines. Gas mass flow and temperature variations are specific to this application, significantly influencing ORC plant performance. Secure prediction of part-load operation is of particular importance for assessment of plant power output, providing stability and safety and utilizing proper control strategy. In this paper design and off-design cycle simulation model is proposed. Off-design performance of the ORC cycle recovering waste heat from gas turbine unit installed at gas compressor station is considered. Major factors affecting system performance are outlined.
Effect of introduction of fullerene soot on mechanical properties of unidirectional thermoplastic tape
Authors: Kobykhno Ilya , Honcharenko Dmytro , Yadykin Vladimir , Stolyarov Oleg , Tolochko Oleg
Published: December 2018

A series of unidirectional thermoplastic tapes (UD tapes) specimens based on carbon fibers and polyamide filled with fullerene soot in a concentration of up to 4 wt. % was made. From the obtained tapes by the method of hot pressing, composite materials (CM) specimens with 0/0 and 90/90 ply orientations were made. A study of the mechanical properties of the samples obtained by the 3-point bending test was made. Shown that the introduction of fullerene soot up to 2 wt. % can significantly increase the strength and modulus of elasticity of both longitudinal and transverse reinforcement directions. Further increase in the concentration of soot leads to a decrease in properties. A theory that describes the effect of fullerene soot on the properties of CM, including the increase and further decrease in properties, depending on the concentration of nanoparticles was proposed.
Estimation of absolute deformations by changes in distances between the reference points and deformation marks
Authors: Tsareva Olga , Dmitriev Ivan , Kornilov Yuriy
Published: December 2018

The article considers the definition of absolute types of deformations, such as transfer and rotation of a building, using linear spatial intersection. In particular, knowing the distances between strong points and deformation marks, the coordinates of the marks located on the building in the initial and current observation cycles are obtained. Knowing the coordinates of the marks, calculate the displacement vectors of the marks for a certain period of time. The definition of absolute deformations is based on the estimation of the projections of the displacement vectors on the coordinate axes, as well as the direction cosines of the vectors with the coordinate axes. The determination of the direction of displacement is shown for the transference deformation. And how to determine the axis, the distance to this axis and the angle of rotation is shown for rotation deformation. We show for joint deformation of the transfer and rotation how divide it into components and then determine the direction of displacement and the axis of rotation. The results can be used in assessing of absolute deformations buildings of monuments of cultural heritage.
Cybersport: Stages and content of usability testing of gaming interfaces and environments
Authors: Sergeev Sergey , Kaklauskas Arturas
Published: December 2018

The article explores the content and technologies of usability testing of user aspects of gaming interfaces and elements of the gaming environment used in eSports. Areas of usability research and the specificity of the full and intermediate testing in the design of computer games are shown. The stages of preparation and testing are analyzed. The basic principles and methods of the results analysis are considered. The process of the interface design of a software product is conventionally divided into six stages. Each stage uses its own usability testing methods, and their results then become the starting point for using other methods. An enumeration and a brief overview of the research content and usability methods used at each stage of the design of the game interface and game environment are given.
Feasibility study of the insulation of the enclosing walls of high-rise buildings
Authors: Gamayunova Olga , Petrichenko Mikhail , Musorina Tatyana , Gumerova Eliza
Published: December 2018

On the example of a typical residential multi-apartment building, a feasibility study was carried out on the choice of energy-saving measures for the thermal insulation of facades. The decision to increase the energy efficiency of the building was made on the basis of calculating the loss of thermal energy through the external walls. Based on the parameters of the heating period, capital costs for additional thermal insulation of facades and calculated values of operating costs for heating, the optimum thickness of the additional layer of insulation is determined, in which the payback period assumes a minimum value.
Analysis of centralized hot tap water systems calculation’s specifics
Authors: Tumanova Karina , Borodinecs Anatolijs
Published: December 2018

Most of the urban housing stock in Latvia as well as in major part of EU cities is apartment multi-storey buildings, most of which have a connection to centralized hot tap water systems. Also, such buildings as dormitories, university campuses, sporting facilities, mostly are connected to the centralized hot tap water systems. The hot tap water systems can have different optional technical solutions, such as recirculation loop, bath towels warmers, etc. All these options affect calculation’s specifics of the systems. The main challenge for designers is to make correct estimation of hydraulic losses, definition of necessary water flow rate and to choose such technical equipment as circulation pumps, balancing valves and circulation water flow. The main parameters directly affecting the sizing of hot tap water system are the number of inhabitants, designed water consumption, consumption uncertainty coefficient, building’s specifics etc. This study is based on the hot water consumption analysis in building were online monitoring system was installed.
Experimental study of alternating magnetic field in laminated ferromagnetic core
Authors: Adamyan Yuriy , Krivosheev Sergey , Magazinov Sergey
Published: December 2018

At engineering simulations of magnetic fields in ferromagnetic cores standard Preisach and Jiles-Atherton models are commonly used. At that a material magnetic properties are considered similar in all points of a core. However, the view of experimental hysteresis loops can differ from calculated even for materials with well-known magnetic properties, e.g. transformer steel. Experimental registration of hysteresis loops in characteristic zones of laminated steel core have revealed substantial discrepancy as in the loops view as in the field strength distribution in comparison with calculation results. Measurements at the frequency and field amplitude variation in order to reveal their influence on the magnetization process are conducted. The results obtained point to possible significant influence of magnetostriction effect on functioning of the ferromagnetic core. This influence can appear at frequencies of the core mechanical resonance and lead to changes in the core inductance and quality factor. The effect is relatively weakly pronounced at laminated steel core, but in some cases needs to be considered, e.g. if big size core operates at network frequency.
Reconstruction of the transformer theory
Authors: Shakirov Mansur
Published: December 2018

The fallacy of the traditional transformer theory is illustrated. The fundamentals of the new theory, beginning from principle of the transformer action, motion of electromagnetic field in its window, new equivalent circuit and vector diagrams are discussed. More correct decision for the sudden short-circuit in real transformers are presented.
Operation experience of solar power plants connected to the Russian distributed grid
Authors: Koshcheev Lev , Popkov Evgeniy , Seit Ruslan
Published: December 2018

The islanding condition of grid-tied solar power plant with hydro power plant of commensurable power is considered in this article. Based on the results of the article, the relevant conclusions were drawn.
Admissibility assessment of external network based on experimental data equivalence method
Authors: Nikolaeva Elena , Yurganov Alexej
Published: December 2018

Performing calculations of steady-state regimes and to determine the cutset grid capacity obtaining initial data is quite easy if you know the voltage class of transmission lines and their lengths. That is why such calculations in the RastrWin software environment give a good match to the results in kind. To ensure the results coincidence of transient processes, a significantly larger amount of data on the elements dynamic properties of the system and the tuning of the control systems is needed. Therefore, calculations provide an opportunity to compare the effectiveness of various excitation systems, but quantitative estimates of the limits of sustainability in nature and the model, as well as the configuration of excitation system often do not coincide. In the Russian Federation, a methodology for the equivalence of the external network of power plants based on experimental data has been developed and is successfully applied in practice. As a result, it becomes possible to promptly perform stability forecast calculations by dispatching personnel and to select the setting of the automatic control system for excitation by operational personnel in the circuit directly during commissioning tests at power plants. This paper describes accuracy and efficiency assessment of this methodology.
Investigation of the characteristics of the container for storage of radioactive waste of nuclear power plants with uranium-graphite reactors
Authors: Ivshin Aleksey , Kalyutik Alexandr , Blagoveshchenskii Anatolii
Published: December 2018

The article presents the results of the study of neutron-physical characteristics of the container for storage of radioactive waste of nuclear power plants with uranium-graphite reactors. The interaction of gamma quanta (in the energy range from 0.1 to 2 MeV) with the structural materials of the container is simulated. The numerical values of the parameters determining the radiation characteristic of the container with the estimation of the calculation error are obtained. The following main characteristics of the container are determined: the attenuation coefficient of the equivalent dose, the numerical factor of gamma radiation accumulation. These characteristics can be used to justify the radiation safety of the container, in particular when selecting protection materials, as well as when building additional heterogeneous protection barriers.