Method Of Experiment Planning Research Articles

Multi-criteria optimization of metal pressure processes using experiment planning methods

The main task of designing a technology of metal processing by pressure is accurate prediction and ensuring the desired properties of the finished product. However, they often encounter a situation when it is impossible to simultaneously ensure the optimal value of all process parameters and the resulting properties of the finished product. In this case, it is necessary to make an informed decision regarding the assignment of certain numerical values of these parameters. This article proposes to use the mathematical apparatus of experimental planning methods to implement multi-criteria optimization of metal pressure processes. Applying of correlation analysis, function of desirability and a priori ranking by the example of optimization of parameters of the process of hydromechanical extrusion of hard-to-deform alloys is shown. Results of multi-criteria optimization of the process of hydromechanical extrusion of bar blanks from aluminum alloy AMg5 (analog of Al-5056) with the purpose of minimizing the extrusion force, deformation non-uniformity and damage index of the resulting product are presented.

Plasticized epoxy composites for manufacturing of composite reinforcement

Composite rebar is a promising building material due to its advantages over steel rebar. Polymer reinforcement consists of a hardened matrix reinforced with a continuous fiber. The main role of the matrix is to determine the performance properties of the composite and to distribute stresses in the reinforcing filler. Optimization of the polymer matrix composition in terms of strength and technical parameters makes it possible to obtain a composite with high performance properties. The aim of the research was to determine the effect of modifying additives on the properties of the matrix for the production of composites with high technical requirements. When performing research, we considered modifiers that interact differently with the components of the polymer matrix as plasticizers. The first type of additive is able to combine with reactive groups of epoxy resin to form a three-dimensional product. Urea resin was used as such a compound. The second group of samples contained a furfurolacetone monomer-a substance that does not contain reactive groups with the resin, but interacts with the hardener of the epoxy resin. And the third type of modifier is dioctyl phthalate, whose role is to change the intermolecular and intramolecular interaction of the spatial structure that it fills. Optimization of compositions to identify areas with high physical and mechanical values was carried out using mathematical methods of experiment planning. Based on the results of the research, it can be concluded that with the optimal content of plasticizers, in all cases, there is an increase in the compressive and tensile strength indicators compared to materials without additives. Further increase in the content of modifying additives (above the optimal amount) leads to a decrease in strength.

ЗАДАЧА ОПТИМИЗАЦИИ ПРОЧНОСТНЫХ СВОЙСТВ ДРЕВЕСНОГО КОМПОЗИЦИОННОГО МАТЕРИАЛА ДЛЯ ИЗДЕЛИЙ ТРАНСПОРТНОГО СТРОИТЕЛЬСТВА

The article deals with the problem of finding the necessary properties of a polymer composite material for the production of sleepers, which is solved by an experimental statistical method. Solving this problem of multiple-criteria optimization, the necessary values of the mass coefficient and the bend of the railway sleeper were determined in natural and coded scales, respectively. The obtained properties of the material for a polymer composite sleeper are selected by reducing the parameters to the minimum permissible values that characterize the stress-strain state of the structure. Optimising the task of finding optimal properties of a sleeper structure made of composite material using this method, we obtain properties of the sleeper that can vary. The response of functions that depend on variable factors is presented in the form of second-order polynomial models in which the coefficients were determined by experiment planning methods. The bending coefficient is necessary to determine the elastic modulus of a polymer-composite sleeper in the longitudinal direction. The mass value is determined from the operating conditions in the railway track block and is 145-154 kg, the value of the elastic modulus in the longitudinal direction is 6200-7600 MPa, and in the transverse direction-not less than 1000 MPa.

MATHEMATICAL MODELING OF PROCESSES OF SEPARATION OF COMPONENTS OF GRAIN MATERIAL IN THE COMBINED VIBRATION-AIR SEPARATOR

Development of a mathematical model and calculated analytical dependencies for determining the trajectories and parameters of grain movement in a vibro-fluidized layer of grain material components under the action of a pulsating air flow. They are based on the methods of deterministic mathematical modeling and theoretical mechanics based on the equations of motion of a material point at a variable air flow speed and the action of a pulsating air flow. Theoretical studies were carried out using the methods of mathematical analysis and modeling. The research results were processed using elements of the theory of probability and mathematical statistics using software packages; to determine the rational parameters of the process, the method of statistical experiment planning was used. A mathematical description of the motion of the grain material particles in a combined vibration-air separator under the action of a pulsating air flow of variable speed is given. The trajectories of motion of particles with different sizes are obtained. The obtained equation of motion of a particle under the influence of a pulsating air flow makes it possible to determine the dependence of the speed of movement of the material in a vibro-fluidized layer of grain material on a number of factors: the geometric parameters of the sieve-free sieve, the feed angle of the material, the initial kinematic mode of the material, the index of the kinematic mode of the sieve-free sieve, as well as the coefficient of windage of the grain. On the basis of theoretical studies, the possibility of separating particles of grain material into fractions according to aerodynamic properties with vibropneumatic loading of grain into the channel has been determined. The use of a pulsating air flow as a separating carrier, and taking into account the deflecting forces, made it possible to significantly increase the splitting of the trajectories and the criterion for dividing the grain into fractions.

Ergonomic design of overalls for agricultural workers of Uzbekistan

This article focuses on the design of workwear based on ergonomic research. Conducted research allowed to obtain the results of the analysis of changes dimensional features and calculate dynamic effects for ergonomic patterns of postures of agricultural workers. The selection of the optimal values of the design parameters of workwear was carried out on based on the development of mathematical models using static methods of experiment planning, which makes it possible to implement all kinds of combinations of the considered levels of factors, and the results are evaluated using static analysis. On the basis of the carried out ergonomic researches results of the analysis of changes of dimensional signs and calculation of dynamic effects for ergonomic poses on the basis of which optimum sizes of additions on free fitting were chosen are received and the rational design of overalls for agricultural workers of Uzbekistan is constructed. Novelty of the constructive solution of overalls for agricultural workers is confirmed by the positive decision on issue of the patent Of Agency on intellectual property of the Republic of Uzbekistan for the industrial design of overalls under the application No. SAP 2018 0263.

Optimization of Teaching Boys Aged 10 Mae-Geri (Front Kick) Technique in Kyokushin Karate

The objective of the study was to substantiate the influence of selected factors on the effectiveness of teaching a series of tasks aimed at motor skills development in boys aged 10. Materials and methods. The study involved 32 boys aged 10. The children and their parents were informed about all the features of the study and gave their consent to participate in the experiment. To achieve the objective set, the following research methods were used: study and analysis of scientific and methodological literature; pedagogical observation, timing of learning tasks; pedagogical experiment, methods of mathematical statistics, methods of mathematical experiment planning. During training, a method of algorithmic instructions was used. Results. Regression dependence is observed throughout the entire period of performing the series of learning tasks. The constructed mathematical models adequately describe the obtained data. The calculated regression coefficients are statistically significant (Fр < Fkр). Throughout the experiment, the factor X1 “number of sets” had a constant positive effect on the target feature (Y). The percentage contribution in the first series of learning tasks was 87.8%, in the second – 32.3%, in the third – 55.1%, in the fourth – 77.2%, in the fifth – 68.9%, in the sixth – 54.03%. The factor X2 “rest interval” had a negative effect starting from the second series – 67.3%, the third – 40.4%, the fourth – 19.3%, the fifth – 30.6%, the sixth – 45.05%. The effect of first-order interaction (X1X2) was not observed during all the series of learning tasks. Conclusions. The optimal modes of performing the series of tasks for teaching boys aged 10 the Mae-geri (front kick) in Kyokushin karate are the following: series 1 – 3 sets, rest interval 60-120 s; series 2 – 1-3 sets, rest interval 60 s; series 3 – 3 sets, rest interval 60 s; series 4 – 3 sets, rest interval 60–120 s; series 5 – 3 sets, rest interval 60 s; series 6 – 3 sets, rest interval 60 s.

Modeling of the Receptural Composition Protein-carbon Semi-fabricates

Topicality. The creation of new combined products saves animal raw materials. The use of vegetable purees in the production of food is due to high nutritional and biological value. In view of the above, research aimed at the development of new types of semi-finished protein-based carbohydrates based on milk protein concentrates (MBC) with the addition of vegetable purees are relevant.The purpose of the article is to substantiate the technologies development of protein-carbohydrate (NBC) semi-finished products with the addition of vegetable purees and to perform the modeling of the recipe composition of protein-carbohydrate semi-finished products. The following research methods were used in the writing of the article: standard physicochemical, rheological, methods of experiment planning and mathematical processing of experimental data using modern computer programs.Results. It is theoretically and experimentally substantiated the feasibility of using in the NBC technologies development on the basis of MBK of cuttings, mashed carrots and mashed pumpkin. The composition of new NBS was simulated, which made it possible to narrow the range of variation of the feedstock concentrations in further studies. It is established that the rational concentrations of recipe components for NBC from carrot puree are: mass fraction of MBK 50… 54 %, carrot puree 26… 30 %, sugar 8… 12 %, stabilizer 8… 12 %; for NBC pumpkin puree – MBC mass fraction 46… 50 %, pumpkin puree 30… 34 %, sugar 8… 12 %, stabilizer 8… 12 %.Conclusions and discussions. Developed and modeled NBC technologies using carrot and pumpkin puree to allow more efficient use of the nutritional potential of milk and its processing products in combination with carotene-containing vegetable raw materials. The scientific novelty of the obtained results is the theoretical substantiation and experimental confirmation of the expediency of using MBK made from cuttings, puree from carotene-containing vegetable raw materials in NBC technologies.

Вплив магнітного поля на посівні якості насіння вівса

Ensuring an increase in crop yields and a reduction in plant morbidity without the use of chemicals is an important task. Currently, many researchers have found a positive effect of a constant magnetic field on crop seeds during pre-sowing treatment, which is manifested in increasing crop yields, reducing plant morbidity, improving biochemical parameters and product quality. The aim of the study was to establish the influence of the magnetic field on the sowing qualities of oat seeds during pre-sowing treatment. Experimental studies of the effect of the magnetic field on the germination energy and seed germination were performed with oat seeds of the Desnyansky variety by the experimental planning method. It has been established that the rate of chemical reactions, ion transport, membrane permeability, seed water absorption and oxygen concentration in cells increase during seed treatment in a magnetic field, which contributes to the improvement of seed sowing qualities. It is established that the change of sowing qualities of seeds during their treatment in a magnetic field depends on the square of magnetic induction, the magnetic field gradient and the seed velocity. The most effective mode of pre-sowing treatment of oat seeds in a magnetic field is a magnetic induction of 0,065 T with fourfold re-magnetization, a magnetic field gradient of 0,57 T/m and a velocity of 0,4 m/s.

Model of simulation of the process of formation of functional surfaces of micro-opto-electro-mechanical systems’ components

The subject of the article is to establish the relationships between the parameters of formation the functional surfaces of the substrates of micro-opto-electro-mechanical systems’ (MOEMS) components and their physical and technological parameters. Objectives: to increase the reliability and reproducibility of the received information, reduce the complexity of the technological process of forming, by modeling the dependences of the ratios of physical and technological parameters of forming the functional surfaces of the substrates of MOEMS components for the forming process. The methods are used: methods of experiment planning and computer processing of experimental data, mathematical models, digital computer modeling of technological processes. The following results were obtained: a mathematical model was proposed, which was used to model the influence of physical and technological parameters of the functional surfaces of the substrates of MOEMS components on their formation, with the receipt of prototypes. The results can be used in the development of technological processes of production, as substrates of functional components of MOEMS, and other functional elements for various technological purposes. A mathematical model is obtained, which allows predicting the degree of influence of physical and technological parameters of the technological process on the parameters of formation of functional surfaces of substrates of MOEMS components. Conclusions. The scientific novelty of the results is as follows: a mathematical model that has found practical implementation for computer digital modeling in the development of technological processes for the production of functional surfaces of substrates of MOEMS components is proposed, in which, unlike the existing ones, it is possible to predict the degree of influence of physical substrates of MOEMS components, which allows to plan the process of formation, increase the reproducibility of results and reduce the complexity of the technological process.

Study on particle size distribution of aggregate from coal ash for heat-resistant concrete

In Vietnam, the current amount of thermal ash (fly ash and bottom) remains nearly 100 million tons, causing great environmental and social impacts. The recycling and reuse of this source of waste is an effective solution towards sustainable development. The paper introduces the results of study on some properties and particle size distribution of aggregate from thermal ash, Duyen Hai factory for refractory concrete. Particle composition is calculated and selected according to the density of particle size arrangement with the maximum number of points of contact. The continuous particle size distributions of thermal ash is calculated by Andersen’s formula with Dmax = 5 mm. The bulk density and porosity of the particle mixture corresponding to the vibrating modes is determined. By the experimental planning method (Design of experiments - DoE), the optimal aggregate particle composition was determined with the calculated value of n = 0.387 and the vibration time of 90 s gives the maximum bulk density of 1313.17 kg/m3 and the smallest actual porosity is 34.69%.

Optimization of Alkaline Sulfide Leaching of Gold-Antimony Concentrates

This article covers a hydrometallurgical method for processing of a gold-antimony flotation concentrate in alkaline sulfide solutions. Thermodynamic analysis of the reaction stibnite with sulfide sodium and sodium hydroxide was performed. The chemical and phase compositions of the investigated material, mainly represented by compounds of antimony, silicon, calcium, sulfur and iron are studied. Phase composition: quartz, stibnite, quicklime, pyrite, dolomite and arsenopyrite. The dependences of the influence of sulfide sodium and sodium hydroxide concentration, and the liquid to solid ratio on antimony extraction into solution were determined by methods of mathematical experiment planning. The calculated values ​​of the determination coefficients testify to the adequacy of the chosen two-level model. The optimum parameters of the process were obtained: L/S ratio = 4,5; the nitric acid sulfide sodium concentration was 61.09 g/L; sodium hydroxide concentration was 16.47 g/

Optimization of Siderite Ore Sintering Operation Conditions

Research was сarried out on a pilot plant on sintering of various size siderite ore and limonite taken in various ratios. To study impact of a number of process factors on the sintering process performance and the obtained agglomerate quality at the minimum number of the carried out experiments, one of the experiment planning methods was used, and regression equations were derived. With these equations the effect of the ore size, siderite ore and limonite ratio, solid fuel consumption, sintered layer height on the agglomeration unit performance and the agglomerate metallurgical properties was reviewed. The obtained work results have great practical importance, as they allow optimization of siderite ore sintering operation conditions and production of high quality agglomerate. They may be used at a variety of the country agglomeration factories, where siderite ores will be used as iron ore component of the sinter burden.

Possibilities of Developing of Metallurgical Data Dumps

Data about the technological production characteristics are sent to the archive, where they will be stored for many years. However, the stored data contains many undisclosed links between technological factors and technical and economic production indicators. The article presents a hypothesis about the possibility of processing data generated during production processes of industrial enterprises by analogy developing mining and physical dumps. The article provides an example of studying the sufficiency of the volume of a data metallurgical dump for constructing mathematical models using the experimental planning method. Samples from real production data dumps can compensate for the difficulties of implementing a modern active experiment in training future specialists in secondary vocational and higher education institutions. It is established that the data accumulated over the year in the production archive contain the necessary combinations of realizations of random variables for the two-factor model. The interval method of varying the levels of variables enables to construct an experimental matrix for a three-factor model as well.
 Keywords: data dump, production data, metallurgical data, data analysis in metallurgy, matrix, mathematical planning, production management, model, model parameters identification, interval method.

Motor Skills Development: Optimization of Teaching Boys Aged 15 Press Headstand and Handstand

The study objective was to substantiate the modes of alternation of physical exercises and rest intervals when teaching series of tasks aimed at motor skills development in boys aged 15 years.
 Materials and methods. The participants in the study were 40 boys aged 15. The children and their parents were fully informed about all the features of the study and gave their consent to participate in the experiment. To achieve the objective set, the following research methods were used: study and analysis of scientific and methodological literature; pedagogical observation, timing of training tasks; pedagogical experiment, methods of mathematical statistics, methods of mathematical experiment planning. During training, the method of algorithmic instructions was used.
 Results. The study found that the effectiveness of mastering series of training tasks depends on a mode of alternation of exercises and rest intervals. The results of analysis of variance and regression models show that the optimal mode of performing series of training tasks is within the range of 6-12 exercise repetitions with rest intervals of 60-120 sesonds. In the proposed matrix of factorial design, the selected step of factor variation is sufficient to study the impact of different modes of physical exercises on the effectiveness of teaching children and adolescents.
 Conclusions. The best options for teaching series of tasks to boys aged 15 during physical education classes are the following: series 1 – 12 repetitions, rest interval of 60–120 s; series 2 – 12 repetitions, rest interval of 120 s; series 3 – 12 repetitions, rest interval of 120 s; series 4 – 12 repetitions, rest interval of 120 s; series 5 – 12 repetitions, rest interval of 60 s; series 6 – 12 repetitions, rest interval of 60 s.

Improving the technology of electromagnetic cleaning of automotive oil by UMS systems

An important direction of increasing the efficiency of using the equipment in the agricultural sector is the control of lubricating and cooling fluids. The main direction of improving magnetic cleaning is increasing the strength characteristics of magnetic field B, increasing the heterogeneity of the magnetic field, and also increasing the area of the magnetic field affecting the cleaned material. (Research purpose) The research purpose is to study the factors determining the level of purification of motor oils from metal and mechanical impurities in the working area of the electromagnetic separator. (Materials and methods) Concentrators under the arbitrary name UMS-2M were developed and installed in the experimental unit to create an inhomogeneous magnetic field in the working area of the electromagnetic separator. The theoretical and experimental research was based on the method of active experiment planning. (Results and discussion) The developed devices for creating an inhomogeneous magnetic field are two identical infinite chains, to which rods with spiral-shaped concentrators are attached with equal pitch. The symmetric second-order rotatable uniform plan is implemented to obtain a model of creating a force characteristic of a magnetic field. The article presents the results of theoretical and experimental studies that determine the main factors affecting the level of purification of motor oils in the working area of the separator. Three-dimensional response surfaces with variants of factor values are presented. The optimal values of the design parameters of the magnetic field concentrators of the electromagnetic separator were determined. (Conclusions) It is shown that the optimal parameters of magnetic field concentrators installed in the working area of the UMS-2M electromagnetic separator are: wire diameters of 3 millimeters, the distance between the threads of the concentrator is 11 mm. At the same time, the distance between the concentrators should not exceed 30 millimeters with an applied voltage of 48-50 volt.

Production tests of the experimental sample of the universal flow distributor of stem materials from rolls on the basis of the KTU 10A feed distributor

Annotation Purpose. Improving the efficiency of the technological process of distribution of stem roll materials for feed and bedding on cattle farms with the use of universal technical means based on the feeder type KTU-10. Methods. Analysis of technological processes of distribution of stem materials for feed and litter for cattle. Experimental planning method and experimental calculation method. Results. In ZRCML NSC “IAEE” together with LLC “Orikhivsilmash” made an experimental sample on the basis of the feeder type KTU-10 with new working bodies of the current principle of action for small-volume separation and delivery of rolled stem forage and litter materials. It was tested on an existing dairy farm for 356 dairy cows with loose-box technology of keeping animals of LLC “40 years of Agro” in the village Smyrnove, Bilmatskyi district, Zaporizhia region. The use of a universal distributor based on KTU-10A on a farm for 350 cows in comparison with the Siloking Compakt mixer (10 m3) will reduce capital investment by 76.9%, specific fuel costs by 28.5%, specific operating costs by 29.5%. The estimated annual economic effect from the use of a streaming distributor when servicing 100 cows is UAH 121.3 thousand. Keywords: rotary and bitters working bodies, streaming distribution, forages, bedding, rolls, bales

Ash-slag binders derived from thermal power plant wastes

This research deals with the Portland cement hydration processes in the presence of chemical additives. The slag-alkyne binders based on bottom ash are under investigation. It has been solved the problem of utilization the wastes from the thermal power plants. The components of slag-alkyne binders have been tested, normal gravity of cement mixture with the additives has been determined, and cement mixture curing period was measured. The possibility of deriving the ash-slag binders of the thermal power plant wastes was discovered. The methods of mathematical experiment planning were applied to assess the influence levels of chemical additives on the properties of alkyne-slag binders. The presented results provide the thermal power plants with a solution to how the industrial wastes can be disposed of in an environmentally friendly fashion. The spreadsheets with research data are provided along with the equations for the binders’ properties correlation with the number of chemical additives used and its fraction in the total composition.

Artificial Porous Aggregate Based on Cullet and Ash-Slag Wastes

The possibility of obtaining artificial porous aggregates based on cullet and ash-slag wastes from thermal power plants is examined. Experimental studies are performed to optimize the aggregate production technology. The method of experimental planning was used to minimize the number of experiments and maintain statistical reliability of the results. The Multiple Regression module of the STATISTICA system was used to construct multi-factor regression models.

Innovative technology for dismantling the windings of electric motors using ultrasonic radiation

The use of ultrasonic radiation showed an advantage over the existing methods of dismantling the windings of electric motors (EM). The method is based on the cavitation impact of ultrasonic vibrations and the capillary effect, which helps the caustic soda solution (NaOH) to quickly penetrate into the thickness of the lacquer impregnation and contribute to the destruction of the insulation from the inside. Analysis of dismantling of EM windings on the basis of ultrasound was carried out by the method of active experiment planning. As a result, a mathematical model of the process of removing the “burnt” EM winding was obtained, and the optimal parameters of power and duration of ultrasound, the temperature and the concentration of the NaOH solution were determined. Asynchronous electric motors (AEM) are the most widespread receivers of electrical energy. To ensure reliable and trouble-free operation of the AEM as a part of technological processes, it is necessary to implement completely new methods for their protection with the possibility of preventive action, carrying out continuous monitoring of motor parameters. In contrast to the systems of classical protection, which are triggered by faults, the system being developed makes it possible to avoid severe emergencies by predicting and detecting damages at an early stage.

Application of the experimental design algorithms to the construction of estimated subsets of minimum covariance determinant method

The problem of stable estimation of errors in variables models is considered in this paper. The basic concepts of experimental design methods, orthogonal regression method, the minimum covariance determinant method are investigated. Experiment planning methods use to form estimated subsets in order to achieve more accurate estimation results. Designs of experiments will allow one to receive the most informative points on which estimation will be made. Research, displaying change in the condition of the D-optimal design when applying different spectra of the design and in the conditions of various kinds of emissions, has been conducted in this work. According to the research it is found that the most accurate estimates are obtained when applying the methods of experiment planning.