Method Of Experiment Planning Research Articles

Thermoviscosimetric characteristics of borosilicate glasses with regard to the promising area of low-melting compositions currently being developed for the removable small-scale melter designed by Mayak Production Association

Relevance. The need to obtain experimental data on dependence of thermoviscosimetric properties of the examined borosilicate glasses on temperature, in order to solve the problem of developing a low-melting composition of borosilicate glass for a small-scale melter designed by Mayak Production Association. Aim. To get the most complete characterization of the glasses under study using thermoviscometric measurements. Methods. Mathematical modelling, simplex-lattice design. Results and conclusions. One of the most effective methods of experiment planning, which allows, with a relatively small number of experiments, obtaining a mathematical model reflecting the dependence of the studied property of the mixture on the content of components in it, is the simplex experiment planning method. To simplify the solution of such a task, a group or groups of components are usually distinguished, in which the ratio of the mass fraction of the components does not change. In this article, three groups of components are taken – simulators of high-level radioactive waste, sodium and boron oxides, and glass frit. The authors have identified the most promising area, where the mass fraction of glass frit is from 67.5 to 75%, the mass fraction of sodium and boron is from 25 to 32.5% and the mass fraction of high-level waste components is from 0 to 20%. The paper presents the results of thermoviscometric measurements of 15 melts of low-melting borosilicate glasses of different compositions at temperatures ranging from 700 to 1,200°C. Using simplex-based mathematical models of experiment planning, domains of dependence of thermoviscosimetric characteristics of glass melts on their compositions were created. The authors identified the compositions of glass melts that are found within the viscosity limits determined as allowable for glass melt discharge during operation of the removable small-scale melter of Mayak Production Association design.

Modeling and optimization of production process of extruded protein textures in meat products technology

In the production of extruded protein textures, the method of multifaceted experimental planning was considered using the recurrence plan of the central composition. The work created a mathematical model of mass exchange in the extraction process layer to obtain the main factors of extraction kinetics (layer, solvent velocity, particles, and longitudinal mixing coefficient) to parameters (internal diffusion coefficients). Carasora protein concentrate was used as the object of the study. Carasora is a wonderful plant, which is used in various fields of production, as well as multifunctional food products in the form of fats, seeds, and proteins. Carasora provides not only rich protein, but also natural dietary fiber and healthy fatty acids, which makes carasora proteins useful for vegetarians and vegans. Because of these qualities, we plan to use pure extruded protein textures from carasora and have developed a mathematical model to find appropriate uses.

Modeling of Accelerated Hardening of Self-Compacting Concrete by Methods of Mathematical Experiment Planning

Modeling of Accelerated Hardening of Self-Compacting Concrete by Methods of Mathematical Experiment Planning methods of mathematical planning of the experiment makes it possible to comprehensively assess the influence of prescription and technological factors on the strength characteristics of heat-treated self-sealing concrete. It was found that for the studied self-sealing concrete on sulfate-resistant Portland cement, the holding time before applying the coolant should be 4.8 hours, and the maximum heating temperature of concrete should not exceed 48оC.

Proportioning of steel fiber concrete tailored composition using the method of mathematical experiment planning

Suggested proportioning of steel fiber concrete tailored composition can be made by using the method of mathematical experiment planning. A wide variety of types of fiber, the size and aggregate grain-size distribution, the number and characteristics of cement, and the need to obtain concrete mixes of different fluidity are used in the production of fiber reinforced materials. That is why it is impossible to develop a proportioning standard method. Thereby it is suggested to conduct an experiment of proportioning of steel fiber concrete tailored composition using the method of mathematical experiment planning in each specific case. The article provides an example of proportioning of steel fiber concrete on specific components. When planning the experiment, we selected water-cement ratio, cement consumption, fiber reinforcement content and the ratio of the content of coarse and fine aggregates as the independent factors. The compressive and tensile strengths of steel fiber concrete and the fluidity (stiffness) of the mixture were selected as responses. This article presents the possibility to make a choice of the ratio of the number of primary components for obtaining steel fiber concretes with the necessary characteristics by analyzing the obtained regression equations.

COMPOSITE MIXTURES OF LIGNOSULFONATE REAGENT SYSTEMS WITH SILICON COMPOUNDS

The relevance of the article is related to the study of the possibility of improving the quality of lignosulfonate systems used during the passage of intervals of swelling clay rocks. A feature of reagent systems based on lignosulfonates is their ability to inhibit the hydration processes of clay minerals and thereby reduce the risks of complications during the construction of oil and gas wells. The properties of the composition were studied on the basis of a mixture of lignosulfonate systems and silicon compounds using the example of ferrochromolignosulfonate (FHLS-M) and sodium silicate Na2SiO3 (SS). The objective of the study was to find optimal ratios of the components of the mixture by the method of experimental planning, as a means of constructing mathematical models and regression analysis to assess the magnitude and direction of the impact of various factors on the output parameters of the flushing fluid system. The research method consists in determining the stability of the solution parameters with varying temperatures from 20 to 190 °C in the aging cell for 5 h and conducting at least three parallel determinations for each ratio of reagents in the composition relative to the initial clay solution. The performed regression analysis of the composition of FHLS-M: SS showed that the greatest influence on the viscosity and filtration properties of the solution is exerted by the content of FHLS-M. However, in the temperature range of 80-190 °C, the ratio of FHLS-M: SS is justified, equal to 3%:5% (the addition of SS enhances the effect of the composition by more than 40%). In the temperature range of 20-120 °C, to maintain the conditional viscosity of the solution (CV) at least 60 s, a sodium silicate content of about 4 % is required, FHLS-M – within 3-5%. At temperatures of 80-120 °C and a value of CV = 60 s, the composition of the composition of FHLS-M: SS is 3%:4%, respectively; with an increase in temperature of more than 120 °C, there is a need to increase the consumption of FHLS-M. At the same time, in the temperature range of 80-190 °C, the ratio of FHLS-M: SS is justified at the level of 3%:4%, respectively. It was found that the optimal ratio in the temperature range of 20-190 °C, in the composition of FHLS-M: SS, is 0.75%:0.75 %, respectively, however, the conditional viscosity (CV) of the solution is no more than 35 s. A decrease in the filtration index (FI) of the solution at temperatures up to 80 °C is ensured by the use of less than 2% sodium silicate in the composition, and FHLS-M in the range of 2-5%.

The Development and Adaptation of a Predictive Model of Full-Factor Optimisation of the Basic Probiotic Fermented Dairy Product Technological Process

Introduction: In the conditions of rapidly developing markets and the increasing needs of the population for new types of products with long shelf life, there is a need to expand their range, further improve their quality and biological value, and modernize traditional technologies. The main means of achieving these goals is to increase the efficiency and quality of scientific research and accelerate the introduction of scientific achievements in industry. The latter will make adjustments to accelerate the development of effective technologies of whole-milk products. The use of new methods of experiment planning in order to optimize technological processes will reduce the duration of research on the creation of new types of products.Purpose: The article is devoted to the research related to the development and adaptation of a predictive (mathematical) model for optimization of the technological process of probiotic fermented dairy product production. This approach will allow to ensure the design of a certain set of formulations for probiotic fermented dairy product, in which the relative biological value (RBV) will correspond to the maximum value at satisfactory given process parameters.Materials and Methods: The objects of research were: probiotic fermented dairy product manufactured in accordance with the developed mathematical model of the process. The search of specialized literature was carried out using electronic databases: E-library, Scopus, MDPI, Science Direct. Mathematical processing of experimental data for the development of the probiotic fermented dairy product model was carried out using Microsoft Excel 2010 (Microsoft Corporation, Ink.) with the "Solution Search" add-in, as well as specialized software packages TableCurve 2D v.5.01 (SYSTAT Software, Ink.) and Wolfram Mathematica 10.2 (Wolfram Research, Ink.).Results: A mathematical model for optimization of the technological process of probiotic fermented dairy product production was developed. A full-factor experiment (FFE) was conducted, in which the mass fraction of sucrose ( , %) and fat-protein index (r) - the ratio of the mass fraction of fat to the mass fraction of protein in the normalized mixture in the intervals from 0 to 10 and from 0 to 1.5%, respectively, were taken as independent factors. RBV was taken as the resultant factor. Based on the results of the research, a refined mathematical description of the dependence of RBV indicator on the mass fraction of sucrose and fat-protein index was obtained. The set of data on the influence of the mass fraction of sucrose on the dynamics of local maximum of RBV and the dynamics of the corresponding values of the mass fraction of fat showed that the maximum of RBV equal to 244.866% corresponded to the mass fraction of sucrose equal to 7.31%. The latter corresponded to the optimum fat-protein index of 1.241. In order to ensure maximum RBV, the lower limit of the mass fraction of fat had to correspond to 3.475%. The analysis of the FFE data showed the presence of additional corrective factors of RBV indicator dependence on fat and protein mass fraction indices. To refine the developed model taking into account additional factors, a correction factor (Q) was introduced into it.Conclusion: Approbation of the optimization model of the technological process of probiotic fermented dairy product production and the obtained mathematical dependencies can serve as a criterion for the formation of a set of formulations for the production of sugar-containing fermented dairy products with a high potential of relative biological value. It should be taken into account that the definition area of this approach is limited in terms of mass fraction of fat in the range from 0.06 to 4.84% and mass fraction of protein - from 2.8 to 3.9%. With this approach (model development) it is possible to analyze promising modes for the studied process, which in real conditions at the experimental stage are not always possible to obtain. The development of this model will significantly reduce the duration of research on the optimization of the technological process.

STUDY OF THE POSSIBILITY OF INCREASING THE PLASTICITY OF TUNGSTEN WIRE AT NORMAL TEMPERATURES BY OPTIMIZING THE DRAWING TECHNOLOGY

Purpose. The development of a mathematical model for the process of drawing a tungsten-thorium wire for the analysis of the influence of technological factors of the specified process on the plasticity of the material and the recommendations on how to choose their optimal values, from the point of view reaching the plasticity of the wire at the maximum productivity of the wire drawing process.
 Research methods. The problem of creating a mathematical model for investigating the influnce of technological parameters into the process of drawing on the plasticity of a tungsten-thorium rod was considered to be based on the theory of experiment, in particular the method of experiment planning. Various material samples were prepared using methods of powder metallurgy and pressure treatment, in particular wire drawing. Experiments were carried out in real production conditions using industrial equipment. The plasticity of the tungsten-thorium rod was determined by torsion testing using the K-5 machine.
 Results. A mathematical model has been created that adequately describes the impact of technological factors on the plasticity of tungsten wire, which allows thoroughly analyze the physical processes that occur during wire drawing, and, if necessary, correct regimes without conducting a large number of physical experiments.
 Scientific novelty. The mathematical model has been proposed as it allows to analyze the impact of technological factors of drawing process on plasticity of tungsten-thorium wire produced at real manufacturing.
 Practical value. It can be useful for the technologists for higher productive application of industrial equipment and decrease of expenses for production of experiment consignment.

Research of the combined sowing working body

Today, the issues of ecology, resource conservation and reduction of production costs in agriculture are associated with the development of combined tillage - sowing machines, which make it possible to reduce a number of technological techniques. Taking into account these factors makes it possible to equip agricultural enterprises with means of mechanization adapted to the specific conditions of their production use. Therefore, a promising direction is the development of universal and combined machines, that is, technical means of mechanization capable of performing several technological operations in one working cycle or, after relatively simple retrofits, ensuring the consistent execution of a number of operations. To carry out experimental studies, an installation was developed and manufactured, which is a combined machine that provides pre-sowing tillage, strip spreading sowing, mineral fertilizers and post-sowing rolling. Using the experimental planning method, mathematical models have been developed that link factors such as the speed of the unit, the angle of attack of the coulter's paw, the depth of the coulter's paw when optimizing the degree of soil crumbling, pruning of weeds, changes in soil hardness. Analysis of mathematical models shows that factors in a certain way affect the quality of tillage (crumbling, hardness, pruning of plants). In the first place in terms of significant importance is the speed of movement. The degree of pruning of plants depends on the angle of attack. As for the depth of processing, this factor has practically no effect on the degree of pruning of weeds. This can be explained by the fact that the root system is located at a shallow depth. For other cultures, this factor may play a significant role.

Study of the influence of the current distortion power of the secondary winding of a transformer on the level of losses in it using the method of experiment planning

Purpose. Detection the relationship between the level of losses of a three-phase transformer and the power of distortion caused by current harmonics.. Methodology. During the research, the methods of determining power losses and additional losses in the elements of the electrical system from higher current and voltage harmonics, the visual programming method, the experiment planning method, and the orthogonal central composite plan method were used. Findings. An analysis of the indicators characterizing voltage and current distortions was carried out, and it was found that these distortions are most fully characterized by the current distortion power and voltage distortion power. These indicators are used to analyze the transmission of electric energy by a transformer of a traction substation. It is noted that the order of harmonics in the distortion power is not eliminated, and higher harmonics are taken into account by the corresponding effective current of higher harmonics. The specifics of the transformer secondary winding connections to the consumer, namely the grounding of one of the secondary winding phases, were taken into account. A number of combinations of current harmonics were used to simulate current distortions. The experiment was carried out using the planning method. The coefficients of the quadratic regression equation that relates power losses to the level of load current harmonics of the third, fifth, and seventh orders are obtaine To determine the significance of the obtained coefficients of the regression equation, the variances and the corresponding values of the Student's criterion were calculated, as a result, factors that do not affect the process and can be excluded from the regression equation were identified. The adequacy of the obtained regression equation was checked by Fisher's criterion. The analysis of the effects and their interaction showed that the standard error of the sample does not exceed 1.66%. As a result of analyzing the combinations of current harmonics that were set during the experiment, it was noted that some of them lead to the same effective phase current, while the power of current distortion is different. The greatest significance of the level of the third harmonic of the current is determined. The constant level of active power on the high voltage side of the transformer is noted, which is due to the absence of voltage distortions on it. Originality. Cases of combinations of current harmonic levels at which the current distortion power index remains unchanged, while the level of transformer power losses caused by current harmonics changes, have been identified. Practical value. This research can be used to assess and reduce the level of power losses in a transformer by filtering certain current harmonics.

EFFECT OF CERIUM OXIDE AND BASICITY OF SLAGS ON THEIR VISCOSITY AND CRYSTALLIZATION START TEMPERATURE

The study of the influence of the content of cerium oxide and the basicity of the slag on the viscosity and temperature of the onset of crystallization of the CaO–SiO2–Ce2O3 system containing 15% Al2O3 and 8% MgO was carried out using the simplex-lattice method of experiment planning, which makes it possible to obtain mathematical models describing the dependence of the property on the composition as a continuous function. Using the experimental data, we built mathematical models that describe the relationship between the temperature of a given viscosity and the composition of the oxide system. Then, by combining the obtained composition-temperature diagrams of a given viscosity on the isothermal section of the composition-viscosity diagram, a set of viscosity isolines was obtained. Generalization of the results of mathematical modeling and graphical display on the isothermal section of the composition-viscosity diagram made it possible to obtain new data on the viscosity of the CaO–SiO2–Ce2O3 oxide system containing 15% Al2O3 and 8% MgO, in the range of basicity 2–5 and the content of 0–15% Ce2O3. Experimental data show that the slags of the studied oxide system, which do not contain cerium oxide, are characterized by an increased crystallization temperature and viscosity in the studied range of basicity. The presence of cerium oxide in the slags of the studied oxide system provides a rather low viscosity and crystallization start temperature in the temperature range of 1500–1550°C. An increase in the content of cerium oxide in slags with a basicity of 2–3 from 1 to 15% is accompanied by a decrease in the crystallization onset temperature from 1490 to 1410°C. Increasing the basicity to 5.0 leads to an increase in the temperature of the onset of crystallization to 1520°C. At a temperature of 1500°C, the viscosity of slags with a basicity of 2.0–3.0, containing 7–15% Ce2O3, varies within 0.2–0.3 Pa · s. An increase in slag basicity to 3.0–5.0 at a fixed Ce2O3 content of 7–15% is accompanied by an increase in slag viscosity up to 1.0 Pa · s and reaches 2.0 Pa · s with a decrease in Ce2O3 to 1–6%. An increase in temperature to 1550°C and a fixed basicity of 3–5 is accompanied by a significant decrease in viscosity, which does not exceed 0.35 Pa · s at a Ce2O3 content of 1–15%.

Optimization of the method of hydrothermal treatment of mogar grain for production of food concentrate "Talkan"

The possibility of using mogar grain for the production of food concentrates based on the traditional national dish "Talkan" is considered. "Talkan" is a national food concentrate for Republic of Kazakhstan, which has been used as a staple food in long-distance trekking by various cultures for centuries. Traditionally, talkan is prepared from various cereals, particularly millet, wheat and barley. When boiling water and oil are added, it turns into a hearty porridge, and when oil and sugar are added, it becomes a delicious dessert. The difficulty lies in the careful handling and preparation of the mogar grain. During intensive cooking, the grain can easily overcook, resulting in all the valuable nutrients being leached into the broth. In addition, improperly prepared mogar can burn during further roasting. To determine the optimal parameters of mogar hydrothermal treatment and to create a high-quality food concentrate based on the national dish "Talkan", a complex experiment was conducted using modern methods of experiment planning. A number of variables were tested during the experiment, including temperature limits and duration of cooking, as well as temperature, duration and intensity of stirring during drying and roasting of mogar. The study showed that the most favourable conditions for mogar grain involve cooking at an initial temperature of between 15–20 °C for about 60 minutes, gradually reaching 100 °C. The drying and roasting processes are best carried out for 25 minutes, with a layer thickness of 25 mm and a surface temperature of 250 °C. The determined of hydrothermal treatment serve as a basis for the design of specialised equipment for preparation of mogar grain for the purpose of making Talkan

Effect of Thermosonication on the Nutritional Quality of Lapsi (Choerospondias axillaris) Fruit Juice: Application of Advanced Artificial Neural Networks.

This study explored the effect of thermosonication on the nutritional properties of lapsi (Choerospondias axillaris) fruit juice. The intent of the present investigation was to process lapsi fruit juice using both thermosonication and thermal pasteurisation and to compare the effects of these treatments on the juice's physicochemical, nutritional, and microbiological qualities. In order to maximise the retention of nutritional properties, enhance juice quality, and boost efficiency, an artificial neural network (ANN) model was also developed to forecast the optimisation of process parameters for the quality of lapsi fruit juice. This study establishes a novel experimental planning method using an ANN to multi-objectively optimise the extraction process and identify the ideal extraction conditions for thermosonication (50, 75, and 100% amplitude at 30, 40, and 50 °C for 15, 30, 45, and 60 min) to augment lapsi juice's nutritional and microbiological properties by improving certain attributes such as ascorbic acid (AA), antioxidant activity (AOA), total phenolic content (TPC), total flavonoid content (TFC), total plate count, and yeast and mould count (YMC). The maximum values for AA (71.80 ± 0.05 mg/100 mL), AOA (74.60 ± 0.28%), TPC (187.33 ± 0.03 mg gallic acid equivalents [GAE]/mL), TFC (127.27 ± 0.05 mg quercetin equivalents [QE]/mL), total plate count (not detected), and YMC were achieved in thermosonicated lapsi juice (TSLJ) under optimal conditions. For AA and TFC, the optimal conditions were 100% amplitude, 40 °C, and 45 min. For AOA and TPC, the optimal conditions were 100% amplitude, 40 °C, and 60 min, and for YMC, the optimal conditions were 100% amplitude, 50 °C, and 60 min. According to the findings, thermosonicated juices have improved nutritional properties, making them an excellent source of bioactive elements for use in both the food and pharmaceutical sectors. According to this study, ANN has been identified as a valuable tool for predicting the effectiveness of lapsi fruit juice extraction, and the application of thermosonication as an approach for lapsi juice preservation could be a potential successor to thermal pasteurisation. This approach can help to minimise or hinder quality degradation while improving the juice's functionality.

Experimental Studies of the Seed-Sowing Device for the Grain Seeder SUBM-3.6

Introduction. Laying the groundwork for developing scientific and engineering efforts and for obtaining the results necessary to create technologies, products, goods and services that provide the independence and competitiveness of the domestic agro-industrial complex is one of the main tasks for ensuring the food security of Russia. One of the most important and difficult agricultural operations is sowing carried out by seeders equipped with mechanical, pneumatic or pneumatic-mechanical seed-sowing devices. Aim of the Article. The purpose of the research is to develop an experimental stand and a methodology for conducting experimental studies of the seed-sowing device for a grain seeder to build mathematical models of its performance when sowing various agricultural crops: wheat, rye, barley, oats, millet, vetch. Materials and Methods. The mechanical roller feed unit is used on one of the most popular and applicable seeder, namely the universal block-modular seeder SUBM-3.6. It allows ensuring the uniformity of the seeding rate and the exact depth of seed embedding. These indicators are the main ones in assessing the performance of seeders. Considering the design features of the above-mentioned seeder is an important step in assessing its productivity. Results. One of the main characteristics of the seeders is their productivity. In the article, there are presented the studies aimed at constructing a mathematical model of the dependence of the seeders productivity on the rotational speed of the drive shaft of the working bodies (rollers) pc (min–1) and the operating length of the rollers lc (mm). For this purpose, an experimental stand and methodology for conducting experimental studies of the productivity of the seeders were developed in accordance with modern methods of experiment planning. Discussion and Conclusion. The analytical dependences of the seeding rate on the rotation frequency and the roller operating length obtained as a result of experimental studies will allow the most efficient use of roller feed units that in turn will influence the choice of optimal operating modes of the seeder SUBM-3.6.

An Experimental Study on the Properties of Concrete and Fiber-Reinforced Concrete in Rigid Pavements.

The complex effect of the amount of cement, polypropylene fiber (the fiber length was 39 mm, and the diameter was 0.45 mm), and polycarboxylate superplasticizer on concrete properties for rigid pavement was determined using the methods of experiment planning and experimental-statistical modeling. The fluidity of all the mixtures was S1. The W/C of the mixtures depended on the composition of the concrete and variable from 0.32 to 0.46. It was found that, by increasing the amount of superplasticizer from 1% to 1.8-2%, the compressive strength of concrete increased by 4.5-6 MPa after 3 days and by 7-9 MPa after 28 days. The flexural strength in this case increased by 0.6-0.9 MPa. The use of polypropylene fiber in the amount of 1.5-1.8 kg/m3 increased the compressive strength of concrete by an average of 3 MPa, increased the flexural strength by 0.5-0.6 MPa, reduced the abrasion capacity by 9-14%, and increased the frost resistance by up to 50 cycles. When using a rational amount of superplasticizer and fiber, the compressive strength of concrete, even with a minimum cement amount of 350 kg/m3, was at least 65 MPa, its flexural strength was at least 6 MPa, its frost resistance was F200, and its abrasion capacity was not more than 0.30 g/cm2. Concrete with such properties can be used for roadways of any type. Low abrasion capacity and high frost resistance provide the necessary durability of concrete for rigid pavement during operation.

Advanced Design for Experimental Optimisation of Physico-Mechanical Characteristics of Sustainable Local Hemp Concrete

The meaning of technological progress is to produce economic development and to increase the level of personal comfort. Sustainability can only be achieved if, at the microsystem level as well as at the macrosystem level, the secondary effects of the activities undertaken by people on the environment are in a state of neutrality compared to the impact they can produce on natural conditions. This neutrality can be intrinsic or can be achieved through coercive and compensatory measures. If we take into account the production of carbon dioxide that accompanies a product from the stages of conceptualisation, design, procurement of materials, execution, operation, maintenance, decommissioning and recycling the waste produced at the end of use, then nothing can be sustainable in pure form. Nevertheless, there are products whose production, both as a raw material and as a technological process, can be neutral in terms of carbon emissions. Moreover, they can even become carbon negative over time. This is also the case with eco-sustainable hemp concrete, whose capacity to absorb carbon dioxide starts from the growth phase of the plant from which the raw material is obtained and continues throughout the existence of the constructed buildings. Not only does it absorb carbon dioxide, but it also stores it for a period of at least 50 years as long as the construction is guaranteed, being at the same time completely recyclable. However, in order to obtain an optimal mixture from the point of view of raw material consumption, represented by industrial hemp wood chips and the binder based on lime and cement, multiple experiments are necessary. The study presented in this work is based on the use of an advanced method of experimental planning (design of experiments method), which makes possible the correlation between the values obtained experimentally and the algorithm that generated the matrix arrangement of the quantities of materials used in the recipes. This approach helps to create the necessary framework for parametric optimisation with a small number of trials. Thus, it is possible to obtain the mathematical law valid within the minimum and maximum limits of the studied domain that defines the characteristics of the material and allows the achievement of optimisation. The material is thus designed to satisfy the maximum thermal insulation requirements that it can achieve depending on a certain minimum admissible compressive strength.

New Thermal Insulation Materials from Waste of Mechanical Processing of Wood

The article describes the conditions for obtaining new thermal insulation materials from the waste of mechanical processing of soft hardwood wood. The recommendations for the production of new resource-saving technologies of gypsum-wood and chip-and-glue composites are justified, which makes it possible to dispose of waste from the processing of soft hardwood wood. It was found that the birch pulp extract, along with cellulose and lignin, contains d-erythrosis, which is easily washed out of the wood with water or a solution of "mineralizer" and gets into the cement dough, which leads to a slowdown in hardening and a decrease in compressive strength. It is shown that the existing technological processes for eliminating the negative influence of saccharides on the strength of wood aggregate composites are complex, requiring multi-stage treatment of the aggregate with various chemicals or long-term exposure. A method based on the use of binders that do not interact with extractable substances, such as gypsum or urea-formaldehyde glue, is proposed. By scanning electron microscopy, it was found that the structure of the gypsum-wood composite varies depending on the sequence of input components. The nature of the effect of microcrystalline cotton cellulose on the change in the physical and mechanical properties of the gypsum-particle composite using cavitation-treated sawdust was revealed and its optimal dosage was determined. The regression dependences of the influence of the consumption of wood chips and glue on the compressive strength of the chip-and-glue composite were obtained by the experimental planning method.

Применение методов планирования эксперимента в экспертных процедурах для машинного обучения модели распределения ресурсов при ликвидации пожара

Introduction. Intellectualization of control systems, including decision support systems, is an urgent need in the field of fire management. There are various types of support for decision makers. The paper focuses on mathematical and referential support, which makes it possible, on the basis of machine-learned optimization models, to prepare for the decision maker a set of suboptimal solutions consistent with his system of preferences. As a basis for the distribution of limited resources of fire and rescue units with simultaneous calls, a transport model is used, the parameters of the payoff function of which are trained on a sample of retrospective data formed with the participation of an experienced decision maker. To select solutions, expert procedures are used that are optimized by experiment planning methods, which can significantly reduce the time to prepare a decision without losing its quality, which makes the study relevant. Purpose of research. The purpose of the article is to construct and illustrate algorithms for applying the principles of optimal design of an experiment in the procedures for expert evaluation of options for distributing homogeneous resources of fire and rescue units over simultaneous calls. Methods. Methods of optimization, expert evaluation, machine learning of optimization models, simulation modeling, experiment planning were used. Results and discussion. The proposed technology for accelerating expert procedures for choosing the optimal distribution of homogeneous resources of fire and rescue units for simultaneous calls based on the principles of optimal planning of the experiment is illustrated by the example of two fire and rescue units and three calls. This example shows the effect of reducing the number of necessary assessments performed by decision makers by more than 70 %. In the case of distribution of different types of resources for each of them, a separate procedure should be built, similar to that described in this article. Conclusion. The results of a study of the application of the principles of optimal design of an experiment to speed up expert procedures for choosing by a decision maker the best option for distributing limited resources of fire and rescue units between simultaneous calls are presented. The proposed algorithm seems appropriate to be included in the expert system for supporting the management of fires. Keywords: fire and rescue unit; simultaneous calls; resources; transportation task; expert assessments; experiment planning; decision maker.

Driving cycles for studying brake wear particle emissions on an inertial brake dynamometer

With the development of contemporary drive systems that have a lower or zero emission of exhaust products, a significant reduction in the harmful influence of traffic on the environment has been achieved, but today new pollutants have been identified on the vehicle. One of such non-exhaust pollutant are brakes whose wear can be a significant particulate matter (PM) contributor. Examining the mechanisms of the formation of particles during braking, and therefore, brake wear is becoming one of the important areas of research today. There are several tests and driving cycles that are applied during the research of the brakes, but they are not primarily defined for testing particle emissions during braking. UNECE (United Nations Economic Commission for Europe) has included in its plan the introduction of standardised cycles that will prescribe a brake cycle whose purpose will be to examine the formation of particles. The brake pads are made of a mixture of different materials that ensure the longevity and efficiency of the brake system and the applied materials have different wear intensities in certain operating conditions. The most common laboratory tests in this area are performed using inertial brake dynamometers. This paper presents an experimental planning method of quantifying the influence of some of the operating parameters (initial speed of the vehicle, braking pressure and vehicle’s load per one brake disc-pads friction pair) on the airborne particulate matter for four different brake pads materials during testing on an inertial brake dynamometer.

Modeling and Optimization of the Isolation of Blackcurrant and Black Cumin Seeds Oils Using Supercritical Fluid Extraction

Supercritical fluid extraction is a powerful analytical tool and it is willingly used by researchers for the isolation of various components from different matrices. In our study, the carbon dioxide in the supercritical state was used for the extraction of oils from blackcurrant and black cumin seeds. To determine the optimal conditions for the process (temperature, pressure and time), the method of statistical experiment planning and the Box-Behnken design was applied and the yield of the oils and the content of fatty acids (FAs) were taken into consideration. It has been found that an increase in pressure causes an increase in extraction yield (W), and an increase in temperature, both at constant pressure and time, does not significantly change the yield value. Optimal yield values were obtained for both materials under almost similar extraction parameters: 306 bar/ 43 min/ 50 °C (blackcurrant) and 282 bar/ 40 min/ 50 °C (black cumin). The influence of the above parameters (T, p, t) on the content of FAs in the extracts has a slightly different trend. The use of supercritical carbon dioxide for the extraction of blackcurrant and black cumin seeds allowed for high process yield and high-quality, rich in polyunsaturated fatty acids oils which can be used as a substrate or final product for industry.

Improved Gamma-Decalactone Synthesis by Yarrowia lipolytica Yeast Using Taguchi Robust Design Method

The production of gamma-decalactone (GDL) by Yarrowia lipolytica is mainly based on the biotransformation of ricinoleic acid, derived from castor oil triglycerides. The main difficulty in this process is the multitude of factors that determine the growth rate of microorganisms, and thus affect the efficiency of lactone synthesis. In order to improve the technological aspects of GDL biosynthesis in batch culture, the influence of three factors was determined: substrate concentration, medium mixing intensity, and its pH, using the Taguchi solid design method (based on orthogonal array design). On the basis of four bioreactor batch cultures, the most favorable culture conditions in terms of GDL synthesis were selected using the statistical Taguchi method. The statistical method of experimental planning has shown that the optimal parameters of lactone biosynthesis are a constant pH at the level of 7, a variable mixing speed in the range of 200–500 rpm, and a substrate concentration at the level of 75 g/L. Using these parameters, about 2.93 ± 0.33 g/L of aroma was obtained. The intensity of mixing turned out to be the most important factor influencing the increase in GDL concentration in the medium.