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Naukovi visti NTUU “КPІ”. – 2016. – N 6



OZONE AND HYDROGEN PEROXIDE INFLUENCE ON INTENSIFICATION OF BIOLOGICAL AND PHYSICAL AND CHE­MI­CAL COMPONENTS OF THE IRON AND MANGANESE REMOVAL FROM WATER /O.V. Kravchenko - K. Naukovi visti NTUU “КPІ”. – 2016. – N 6

Background. Compounds of iron and manganese are the most common components that are present in groundwater of nearly all regions of Ukraine. Elevated concentrations of iron and manganese cause deterioration of the organoleptic properties of water, leading to the formation of precipitates, overgrown water supply and water intake valves. Therefore, there is a need to improve existing technologies to extract these elements from the water.

Objective. The aim is to determine the effects of oxidants – ozone and hydrogen peroxide – at doses that are not sufficient for disinfection (0.25–3.0 mg/dm3), compared with the oxygen for iron and manganese removal from water through filtration on the zeolite filters.

Methods. The research was conducted on iron-bearing groundwater. Water is treated with oxygen at the laboratory unit, which consists of aerator closed contact capacity and free-flow filter with zeolite loading. Water ozonation at manganese removal on zeolite filter was conducted in Drexel glasses, which acted ozone-air mix with ozone generator. In experiments with hydrogen peroxide in a container of water was added a solution of said reagent in various concentrations, then the mixture was mixed and lodged in the filter.

Results. It is shown that at concentrations of oxidants 0.25 and 0.5 mg/dm3 biological processes are dominated. From a technological point of view, it is possible to achieve the same depth cleaning at both low and higher doses of ozone. The implementation process in such circumstances would achieve significant savings of ozone and therefore electricity needed for its formation.

Conclusions. The conclusions about the fundamental possibility of intensifying the process of removing compounds of iron and manganese from water through water treatment by ozone in small doses, followed by filtration through a layer of zeolite loadings are carried out. In this regard ozone promotes more efficient removal of water manganese, which is usually quite difficult technological challenge.

Keywords: ozone; hydrogen peroxide; iron removal; manganese removal.

TWO-SIDED EXPONENTIAL SMOOTHING METHOD FOR RESTORING OF DYNAMIC PROCESSES /O.V. Bratus, V.M. Podladchikov, P.I. Bidyuk - K. Naukovi visti NTUU “КPІ”. – 2016. – N 6

Background. Restoring of the true regularities and missed values of time series is an important stage of data preparation for the future modeling and forecasting, therefore development of new methods of restoring is needed.

Objective. To develop two-sided exponential smoothing method for restoring of regularities of dynamic processes evolution; to apply created method for restoring of missed values of London metal exchange average day prices for color metal (zinc) and to compare with methods of restoring by using arithmetic mean, autoregressive approach and exponential smoothing method.

Methods. To achieve the formulated goal the following methods were used: two-sided exponential smoothing method was created; restoring by using of arithmetic mean values with usage of known values; autoregressive approach and exponential smoothing.

Results. Two-sided exponential smoothing method was developed, which contains procedure of smoothing in direct and reversed time. The proposed method was used for restoring of dynamic processes and missed values of time series. Restoring of mis­sed values of average daily prices for color metal (zinc) by making use of developed method and comparison with other methods was performed.

Conclusions. It is shown by means of simulation that two-sided exponential smoothing method is effective for restoring of process regularities. The method developed in its application on practice for restoring missing values of zinc prices showed an advantage in comparison with all the methods used in this study by the values of statistical characteristics of adequacy for constructed models, so it could be used in practice.

Keywords: restoring of dynamic processes regularities; restoring of missed values of time series; two-sided exponential smoothing; exponential smoothing; arithmetic mean; autoregressive approach.

THE USE OF PROBABILISTIC MODELLING IN EXPRESS CONTROLLING OF APPLE JUICES QUALITY /I.I. Poberezhets, L.E. Kovalyov - K. Naukovi visti NTUU “КPІ”. – 2016. – N 6

Background. Quality control of plant juice in the process of its mass production.

Objective. Development of support system for decision making in the process of express monitoring of the plant juice quality on the basis of electroacoustic measurements.

Methods. Theoretical and experimental substantiation of expedience of the use of a new criterion for juice quality evaluation which is based on the regularities of distribution of electromagnetic waves due to the concentration of the dry substances in juice.

Results. The support system for decision making on the basis of Bayes networks in express monitoring and modeling of plant juice production is developed on the basis of their physical characteristics.

Conclusions. The use of the suggested support system for decision making allows increasing substantially operational efficiency of the production line due to the potential possibility for prognosticating end product quality and making fast corrections of its production regime.

Keywords: Bayesian network; automatized measurement complex; electroacoustic device; juice quality control.

TRAINING DATA EXPANSION AND BOOSTING OF CONVOLUTIONAL NEURAL NETWORKS FOR REDUCING THE MNIST DATASET ERROR RATE /V.V. Romanuke - K. Naukovi visti NTUU “КPІ”. – 2016. – N 6

Background. Due to that the preceding approaches for improving the MNIST image dataset error rate do not have a clear structure which could let repeat it in a strengthened manner, the formalization of the performance improvement is considered.

Objective. The goal is to strictly formalize a strategy of reducing the MNIST dataset error rate.

Methods. An algorithm for achieving the better performance by expanding the training data and boosting with ensembles is suggested. The algorithm uses the designed concept of the training data expansion. Coordination of the concept and the algorithm defines a strategy of the error rate reduction.

Results. In relative comparison, the single convolutional neural network performance on the MNIST dataset has been bettered almost by 30 %. With boosting, the performance is 0.21 % error rate meaning that only 21 handwritten digits from 10,000 are not recognized.

Conclusions. The training data expansion is crucial for reducing the MNIST dataset error rate. The boosting is ineffective without it. Application of the stated approach has an impressive impact for reducing the MNIST dataset error rate, using only 5 or 6 convolutional neural networks against those 35 ones in the benchmark work.

Keywords: MNIST; convolutional neural network; error rate; training data expansion; boosting.

ESTIMATION METHOD OF STRUCTURAL COMPLEXITY OF MASTORVITO MULTIPLIER IN GF (pm) IN RESPONSE TO THE INTERNAL ELEMENTS /O.Z. Shologon, Yu.Z. Shologon - K. Naukovi visti NTUU “КPІ”. – 2016. – N 6

Background. In the multipliers which use Galois filed GF (pm) with large order the hardware complexity allows implementation on FPGA chip, but high structural complexity prevents to do it. That’s why it is important to conduct research in Galois field GF (pm) to determine the field in which the structural complexity is the lowest.

Objective. Develop the method for evaluating structural complexity of Mastorovito multiplier in response to the internal elements.

Methods. Structural complexity of Mastorvito multiplier in Galois fields was determined by combining VHDL and SH models in a VHDL-SH model. In order to find the field with the least structural complexity, the extended Galois field GF (pm) with the same number of elements was analysed.

Results. The relationship between structural complexity of Mastrovito multiplier in Galois fields GF (pm) and number of field bit in the capacity of the field was identified. The results for structural complexity of Mastrovito multiplier in Galois field GF (pm) using internal elements were modified.

Conclusions. Method for calculating the structural complexity of Mastrovito multiplier in GF (pm) was developed. The structural complexity was calculated by combining VHDL and SH models in a VHDL-SH model. It was determined that structural complexity of the multiplier depends on capacity of the field GF (pm), wherein the calculations are carried out. The structural complexity of Mastrovito multiplier in GF (pm) with approximately the same number of elements was calculated, where pm≈625, pm≈78502725751, pm≈1,93485E+15. In calculating the structural complexity without internal elements the structural complexity of the multiplier is less, when the difference between the capacity of the field and number of field bit in the field order is growing. In calculating the structural complexity with internal elements, structural complexity of multiplier is less when the difference between number of field bit and field capacity is equal. This method application can help to develop Galois field multipliers GF (pm) with big order.

Keywords: Galois field GF (pm); VHDL-SH model; Mastrovito multiplier; structural complexity.

FINISH HONING WITH BORIUM HONES OF FRICTION PARTS BORES OF WEAR-RESISTANT HIGHLY ALLOYED NICKEL-BASED COMPOSITES FOR PRINTING MA­CHINES /A.P. Gavrysh, T.A. Roik, P.O. Kyrychok, O.I. Khmiliarchuk, O.S. Khlus - K. Naukovi visti NTUU “КPІ”. – 2016. – N 6

Background. The study on technological process of the finish honing-process of the bores of wear-resistant composite material parts, synthesized on the base of utilized and regenerated wastes of production from nickel alloys ХН55ВМТКЮ, ХН50ВТФКЮ ЭП975 with СаF2 hard lubricant additions has been researched.

Objective. The purpose of the work is the experimental research of processes of the finishing thin surface honing-process treatment with elbor hones of the surfaces of bores of the friction parts of the printing machines and, influence of abrasive tools composition in the first place, cutting modes, the construction elements of honing head on the roughness, quality, precision of bearing surfaces made of new composite nickel-based materials, and also on characteristics of specific capacity, the elbor take and technological self-cost of the honing-process operation.

Methods. Surface treatment of printing machines nickel-based wear-resistance composite parts with the finishing thin honing-process on the honing-machines with the elbor hones on the ceramic bonds and application of thin cutting modes.

Results. It was demonstrated, that granulosity, material of grain instrument and properties of the elbor hones bond for honing-process operations of the nickel-based composite parts essentially influence on the parameters of surface roughness, precision of surfaces, specific productivity, the elbor take, and technological self-cost of the process. The best parameters of surface roughness, precision of surface, productivity, specific expenses of elbor satisfy honing hones made of ordinary strength elbor (LO) with granulosity 7–14 μm on the ceramic bond (T1–T2) and thin honing-procession modes. Advantages of surface treatment of elbor hones at honing-process operation of different printing machines parts are shown.

Conclusions. It was demonstrated, that quality of friction surfaces made of new nickel-based composite materials, and also economic factors of technological process of treatment (productivity, elbor take, cost of technological operation), substantially depend on the structure of elbor hones (granulosity, bond) and cutting modes. The recommendations on the production were developed.

Keywords: new composite materials; honing; elbor; hones; surface roughness; productivity; parameters of cutting.

EFFICIENCY OF STEADY MOTION AND ITS IMPROVEMENT WITH THE USE OF UNSEPARATED AND SUPER­CA­VI­TATING FLOW PATTERNS /I. Nesteruk - K. Naukovi visti NTUU “КPІ”. – 2016. – N 6

Background. The efficiency of the steady subsonic motion of vehicles and animals in air and water is estimated with the use of different drag coefficients, the drag-to-weight and power-to-weight ratios.

Objective. The improvement of these characteristics with the use of special shaped hulls and wing profiles which remove boundary layer separation and with the use of the supercavitating flow pattern for the high-speed motion in water.

Methods. Analytical and numerical estimations with the use of known results for flow on slender unseparated body of revolution and airfoil and for the steady supercavitating flow pattern.

Results. Simple analytic formulae were obtained for the movement efficiency, the critical Reynolds numbers of the laminar-to-turbulent transition etc. and applied for different terrestrial, aquatic and airborne vehicles, animals and human sport activity. In a rather large range of the Reynolds number 106≤Rey≤108, the use of unseparated shapes yields very substantial reduction of the drag in comparison with the conventional bodies of revolution. In water at Rey>107 the supercavitating flow pattern can be preferable.

Conclusions. This drag reduction opens up prospects for designing different kinds of very effective airborne and high-speed underwater vehicles.

Keywords: unseparated shapes; drag reduction; laminar-to-turbulent transition; supercavitation; drag-to-weight ratio; power-to-weight ratio.

PHYSICAL AND CHEMICAL CONDITIONS OF FORMATION, STRUCTURE AND PROPERTIES OF MULTICOMPONENT COATINGS BY THE TITANIUM, ALUMINIUM, CHROMIUM WITH TIN BARRIER LAYER ON 9HS STEEL /V.G. Khyzhniak, G.Yu. Kalashnikov, V.Yu. Shtoyka, D.A. Poberezhnyi - K. Naukovi visti NTUU “КPІ”. – 2016. – N 6

Background. Methods of alloy treatment with chloride phases have become widespread in chemical and thermal treatment. Chloride gas environments have been successfully used for titanizing, chromizing, aluminizing of metals and alloys. Diffusion saturation of the gas phase has got significant advantages over other methods: high-quality coatings, flexible process control, high performance and efficiency. Study of factors that affect the state of gas environment and directly the phase and chemical composition, structure and properties of coatings is of the great interest.

Objective. The aim of the work is to establish comprehensive thermodynamic conditions of 9HS steel saturation with the layer of nitride TiN by titanium, chromium and aluminum, establishment of the phase composition, structure and properties of coatings and rendering based on the studies of practical recommendations on technical parameters of saturation.

Methods. Multiple saturation of 9HS tool steel was realized in a powder mixture of metals Ti, Al, Cr, NH4Cl activator and Al2O3 inert additives. Counterpoise was estimated in the temperature range 300–1500 K for systems involving saturating metals (Ti, Al, Cr), Cl, C, N, O, elements of base (Fe). Samples with coatings were studied by modern me­­thods of physical material science.

Results. Investigation of gas and condensed state of system Ti–Al–Cr–C–N with different composition in the temperature range 300–1500 K showed a significant probability of 9HS steel saturation by titanium and aluminum, lower by chromium, and formation on surface phases of TiC, TiN. TiN barrier layer inhibits at CTT the division of chromium and aluminum in the outer zones of coatings and promotes on surface layer Cr7C3.

Conclusions. Coatings with microhardness of separate components are formed on 9HS steel with TiN layer after titanium-aluminium chromizing: TiC – 35.6; TiN – 24.5; Cr7C3 – 18.5 GPa. Durability of titanium-aluminium chromi-zing 9HS steel with TiN barrier layer in terms of friction without lubrication is in 13.6 times higher than in the same steel after quenching and low tempering.

Keywords: 9HS steel; coating; saturation; structure; properties.

MATHEMATICAL MODE­LING OF STATIC IMAGING FOURIER TRANSFORM SPECTROMETER FOR REMOTE SENSING / V.G. Kolobrodov, D.V. Pozdniakov - K. Naukovi visti NTUU “КPІ”. – 2016. – N 6

Background. Imaging Fourier transform spectrometer (IFTS) is a perspective system for getting information of the Earth's surface within hundreds of spectral bands. However, the development of such system causes many difficulties because of the large number of parameters that must be taken into account.

Objective. To consider the main stages of work of the IFTS and to propose a sequence of calculating the basic parameters of the device

Methods. A work of the static IFTS is divided into four stages. Instrument design and calculation are suggested to carry out these stages.

Results. As a result of mathematical modeling, the proposed sequence of designing the static IFS is based on the Sanyak interferometer. The basic four stages of work are as follows: creating an image in the entrance slit plane by input optics, forming an interference pattern on the detector, creating a signal by the detector, signal processing and recovering of spectral characteristics. Such division into stages allows investigating separately the impact of each stage on the device characteristics entirely.

Conclusions. The proposed sequence allows defining the main parameters and characteristics of the static IFTS based on Sanyak interferometer, such as the input focal length of the lens, its field of view, bandwidth, spectral range and the number of spectral channels, parameters of matrix detector, which are essential on the design phase. Also, due to this, the creation and optimization of the IFS basic model are accelerated and simplified.

Keywords: imaging Fourier transform spectrometer; mathematical modeling; remote sensing.

ACCURACY IMPROVEMENT OF THERMAL CONDUCTIVITY MEASUREMENT OF LIQUIDS USED BY DIRECT HEATING THERMISTOR METHOD /S.M. Matvienko, S.P. Vysloukh - K. Naukovi visti NTUU “КPІ”. – 2016. – N 6

Background. This work addresses the determination accuracy improvement of thermal conductivity of liquids by direct heating thermistor method.

Objective. The aim of the paper is the determination accuracy improvement of thermal conductivity of liquids by analysis of possible measurement errors and development of methods and means of their reduction.

Methods. Types of materials’ thermal conductivity measurement errors are identified, which allowed differentially approach to their analysis. The introduction of appropriate correction factors, determined through the use of standard liquids, was proposed to reduce the error of the measurement method.

Results. Main causes of errors in the research are considered and effective ways to reduce them are provided. The possibility of reducing the measurement error by accumulating the data of multiple observations and their statistical processing is justified.

Conclusions. Results of experimental studies with control materials using established device, which showed high accuracy and efficiency for measuring the thermal conductivity of liquids are presented.

Keywords: accuracy improvement; thermal conductivity of liquids; direct heating thermistor method.

STRAPDOWN INERTIAL NAVIGATION SYSTEM BASED ON DRY TUNED ROTOR GYRO /A.N. Sapegin, N.A. Romanov, D.V. Buhaiov - K. Naukovi visti NTUU “КPІ”. – 2016. – N 6

Background. Modern strapdown inertial navigation systems based on ring laser and fiber-optic gyroscopes, have large size, weight and cost. This makes them difficult to use in navigation systems for small objects. We investigate the accuracy of the strapdown inertial navigation system based on dry tuned gyroscopes, depending on the sensors characteristics and parameters of the base movement.

Objective. Development of navigation system designs based on using dry tuned gyroscopes as the angle sensors and the evaluation of its accuracy

Methods. Compilation of mathematical and software models of strapdown navigation system based on Poisson kinematic equation and Euler orientation vector. Input information to guide the algorithms used in the form of projections of the angular velocity from gyroscopes, installed in the system. Integration of orientation equations is performed using the Runge–Kutta methods.

Results. System errors for different values of the parameters of gyroscopes and motion base are determined.

Conclusions. The use of dry tuned gyroscopes in small strapdown inertial navigation systems can significantly reduce their weight, size and cost saving with satisfactory accuracy.

Keywords: dry tuned rotor gyro; Poisson equation; Euler vector; math modeling; SINS.

THE APPLICATION OF ACOUSTIC METHOD FOR THE DETERMINATION OF UNIAXIAL MECHANICAL STRESS PROFILE /G.S. Tymchik, M.V. Filippova, M.A. Demchenko - K. Naukovi visti NTUU “КPІ”. – 2016. – N 6

Background. The article is devoted to the problem of determining the actual values of mechanical stress of metal structure sections in the process of operation without discharge using acoustic method.

Objective. Experimentation with the actual mechanical stress in the shelves shaped profiles of metal constructions that are in operation.

Methods. The method of acoustic diagnostics of stress-strain state of sections of metal constructions, based on the differential method of determining mechanical stress for the achievement of the aim of the research was proposed.

Results. Existing mechanical stresses in the shaped profiles of metal constructions for industrial installations in operation are studied. A comparative analysis of the values of the actual mechanical stresses in the shaped profiles calculated for the selected control points is carried out, resulting in a set deviation of the measured values from the calculated stresses in the range of 2.5–3.5 %.

Conclusions. The result of the experimental research and conducted analysis of the values of uniaxial mechanical stress measured using the system of diagnostics of stress-strain state of sections of metal constructions and voltages for the same points of the computational methods for profiles camber, allowed us to draw conclusions about the technical condition of metal constructions of industrial buildings in the construction phase.

Keywords: shaped profiles; actual stresses; metal constructions.

DEVELOPMENT OF COLD CREAM COMPOSITION WITH ANTIOXIDANT PROPERTIES /D.G. Saribyekova, A.N. Kunik, L.V. Saleba, A.A. Ivahnenko - K. Naukovi visti NTUU “КPІ”. – 2016. – N 6

Background. The development of cheaper, but no less effective cosmetic products with antioxidant properties.

Objective. The aim of the paper is to determine the antioxidant, organoleptic, physical and chemical properties of cold cream samples through the use of vitamins A and E for optimal development of cold cream with antioxidant properties.

Methods. The sensory, physical and chemical parameters of cold cream were determined according to DSTU 4765:2007 “Cosmetic creams. General technical conditions”. The antioxidant properties of the ferricyanide method were determined by the ability of the samples to recover iron ferricyanide complex of Prussian blue. The acid number of cold cream was determined in accordance with DSTU 4767:2007 “Cosmetic oils. General technical conditions”.

Results. The use of vaseline oil in the classic cold cream was determined as inexpedient. It is found that cold cream sample with vitamin A at a concentration of 0.3 % has the best antioxidative properties (1.054), a sample with a mixture of vitamins A and E 0.3 % 1.5 % has a somewhat lower activity of antioxidant (0.902), but this combination is more rational from the viewpoint of improving the stability of vitamin A. In studying possibilities of using of vitamins A and E as preserving, found that the addition of these vitamins to cold cream leads to a reduction of acid number from 2.91 to 2.1–2.46 mg KOH/g, which allows increasing the shelf life of cosmetic products.

Conclusions. An optimal composition of cold cream with antioxidant properties through the use of a mixture of almond oil and vitamins A and E is developed.

Keywords: skin; free radicals; antioxidants; vitamins A and E; cold cream.

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