Real Production Conditions Research Articles

FEATURES OF THE IMPLEMENTATION OF PRACTICES IN THE PROFESSIONAL TRAINING SYSTEM OF FUTURE ENVIRONMENTALS

The article is devoted to the analysis of the role of educational and production practices in the system of practical training. Students' practice involves the continuity and sequence of its implementation while obtaining the necessary and sufficient amount of practical knowledge and skills necessary for future work. It was established that mastering modern methods, forms of organization and tools of work in the field of their future profession will highly effectively contribute to the formation of students' professional skills and abilities for making independent decisions during specific work in real market and production conditions, fostering the need to systematically renew their knowledge and creatively apply them in further practical activities.
 It is recognized that the implementation of practices in real-time conditions cannot be compared in terms of efficiency and effectiveness with practices implemented using distance learning methods, but taking into account the challenges of today, the use of distance technologies is the optimal way to fully implement the training of a highly professional ecologist.

Conservators, Creativity, and Control

ABSTRACT This article explores the role of conservators and focusses on their creative agency in the preservation of cultural heritage. It argues that conservators constitute a ‘recursive public’ who collectively make the field both highly collaborative and highly modifiable. The author then sets out how conservators engage in a form of ‘ontological constructivism’ where they use their creative agencies in adversarial, anexact, and generative processes and act as ‘art-developers’ to commit to the next version of a work. Drawing parallels with software development, the author proposes that conservation should be seen as a form of version control that creates time-stamped ‘versions of record’ that persist until the next cycle of care. To emphasise the lack of finality in any artwork the author produces a series of ‘endgames’ to illustrate the ontologically open-ended nature of cultural heritage. The article suggests that in exploring the distributed nature of creative agency through the lens of version control, conservation can provide greater understanding into the real conditions of art and cultural production and how they continue to evolve over time. This then helps disrupt conventional notions of authorship and allows conservation to contribute to a more inclusive understanding of art and culture in our institutions.

Опыт применения цифровых нивелиров и программного обеспечения CREDO НИВЕЛИР для мониторинга инженерных сооружений

Purpose: To present the experience of working with digital levels at a construction site during long-term settlement monitoring settlement of both engineering structures under construction and in operation in conditions of tight time constraints, a significant amount of work, limited resources and adverse observation conditions with the simultaneous need to perform them with high accuracy. Methods: Theory of measurement errors, least squares method, parametric adjustment method. Results: It is shown that digital levels of various manufacturers, although they are used to solve various geodetic problems, and the work of many authors is devoted to the study of the influence of various factors on the accuracy of the result obtained by them, but in real production conditions a number of such factors cannot be excluded, which leads to a deterioration in the accuracy of the leveling results. Practical recommendations for mathematical processing of leveling networks built by digital levels in the CREDO NIVELIR software environment are developed, non-standard types of settlement marks are proposed with an indication of the methodology for performing observations when using them. Based on the known dependence of the tilt angle of the digital level on the ambient temperature, an original method for its determination is proposed, including situations when the obtained value exceeds its compensation limits by the level software. It is shown that the conclusions obtained on the basis of the experience of working with digital levels make it possible to increase the accuracy of such work, as well as reduce their labor intensity, when monitoring the settlement of engineering structures. Practical significance: The conclusions and results presented in the article have been obtained on the basis of long-term control of the settlement of both engineering structures under construction and in operation and can be implemented by engineering and geodetic construction support.

The effectiveness of personal protective equipment made of metallized materials when exposed to extreme levels of infrared radiation

Introduction. The results of the study of the nature of the formation of the thermal state in workers under the influence of extreme levels of the heating microclimate with multifactorial exposure against the background of heavy physical labour, justify the need to develop and experimentally evaluate a set of preventive measures. Such measures need to prevent chronic overheating, with the mandatory use by workers of modern effective personal protective equipment from infrared radiation. 
 The purpose of the study – the study of the effectiveness of personal protective equipment made of metallized materials in real production conditions, for the prevention of chronic overheating from exposure to extreme levels of infrared radiation with multifactorial exposure against the background of heavy physical labour. 
 Materials and methods. To assess the possibility of using personal protective equipment in the conditions of modern forging and pressing production, there were taken protective clothing sets made of the material OXA-440, consisting of a cotton-asbestos lining and a metallized material with an aluminum surface. In the manufacture of prototypes of workwear, the topography and the estimated area of the irradiated area of the body surface, and the moisture and air tightness of metallized materials, were taken into account. The effectiveness of personal protective equipment was evaluated with taking into account the indicators of the thermal state of the workers of the main occupations who used two sets of the specified protective clothing alternately. The thermal state of the body was studied in accordance with the guidelines of the MUK 4.3.1895-04 and the provisions of the standard GOST R ISO 9886-2008. Studies on the hygienic assessment of workwear were carried out in the cold and warm periods of the year. A questionnaire survey was conducted to subjectively assess the usability, design and protective properties of workwear made of metallized material.
 Results. The main sources of thermal radiation in the studied production are incandescent to a temperature of over 1200°C with metal forgings of various lengths and various profile configurations, which largely determine the variability in the degree of radiation intensity of the radiant energy flow at the workplaces of blacksmiths and heaters. The formed thermal state of the workers of the specified occupational groups, dressed in standard cotton workwear, during the performance of the main work operations during the first half of the working shift in the cold and warm periods of the year, is estimated as the maximum permissible, requiring a limit of working time – no more than one hour per working shift. The use of workwear made of metallized materials in the cold period of the year led to a slight improvement in the thermal condition, which allowed to prolong the time spent at the workplace to 2 hours. When using the original design of a protective suit made of a metallized material characterized by moisture – and air-tight properties and covering a large area of the body surface during the warm period of the year, no improvement in the thermal condition of the workers was observed. According to the questionnaire survey, good reflective and mechanical properties of the test material were revealed. The expressed wishes and suggestions of the workers in the areas of improving the design of workwear suggest the development of new design samples of special protective clothing made of this metallized material, taking into account these comments.
 Limitations. The chosen research method determines the limitation on the possibility of its use in relation to a specific production, characterized by the multifactorial nature of the production environment against the background of heavy physical labour and extreme levels of infrared radiation determined by the specifics of the technological process. 
 The obtained research results objectify the subject of further research – the development and evaluation of the effectiveness of new design samples of special protective clothing made of metallized materials.
 Conclusion. The results of the conducted studies have shown good reflective and mechanical properties of the new metallized materials. During the questionnaire survey, the workers expressed their wishes and suggestions for improving the design of workwear sets, which must be taken into account when creating new design samples of special protective clothing, for their subsequent use as the main means of protection when working under conditions of exposure to extreme levels of industrial infrared radiation.

THE MODELING OF ELASTIC DEFORMATIONS BY THE CNC MACHINE TECHNOLOGICAL SYSTEM

The condition for high precision machining of parts on CNC machines is that the actual movements of the cutting tool correspond to the information recorded in the control program. In real production conditions, processing errors often occur, the magnitude of which depends on many factors that are difficult to predict. The occurrence of errors is significantly affected by the technical condition and quality of adjustment of the technological system of the machine, temperature deformations, elastic deformations of the elements of the machine, devices and workpieces from the action of cutting forces. The task of forecasting the amount of elastic deformations and taking into account the data at the stage of preparing the control program is relevant and provides an opportunity to increase the accuracy of processing.
 To create a mathematical model of the formation of the processing error due to the action of elastic deformations of a specific machine, it is necessary to have data on the magnitude and direction of displacement in the space of the elements of the technological system due to the action of cutting forces. The range of efforts and the direction of action must correspond to the conditions of possible processing on a machine of a certain model. The necessary data can be obtained with the help of a device for simulating cutting forces in different places of the working area. According to the results of the research, the values ​​of elastic deformations of the machine elements in different coordinates of the working area are measured. A database is formed for each machine, which reflects the technical condition and rigidity of the elements of the technological system. For ease of recording and further use, a model is built using spline functions based on research data.
 The using of the results by elastic deformations simulation on CNC machines is advisable at the stage of preparation of the processing control program. When calculating the trajectory of the movement of the forming tool, it is possible to make corrections to compensate for the expected errors due to the action of elastic deformations. A significant effect from the implementation of this approach is possible in cases of processing surfaces of complex shape with high accuracy.

Algorithm for the route’sformation of food raw materials procure-ment on the community territory taking into account the production conditions during emergency situations

The article concerns the improvement of the ACO (Ant Colony Optimization) ant colony optimization algorithm for the formationof routes of vehicles for the procurement of food raw materials on the territory of the community during emergencies. The purpose of the study is to improve the algorithm for the formation of routes of vehicles for the procurement of food raw materials on the territory of the community during emergencies. The proposed algorithm is based on the classical algorithm of ant colony optimization ACO and, unlike it, takes into account real production conditions during emergencies. The task of the research is to create an algorithm for the formation of effective routes of vehicles for the procurement of food raw materials in the territory of the community during emergencies, as well as its comparison with the classic ACO algorithm for solving various problems of route formation. It was established that the use of the classic algorithm for the optimization of ant colonies ACO, or its known modernizations, does not provide a high-quality solution to the problem of forming routes of vehicles for harvesting food raw materials on the territory of the community during emergencies.This is due to incomplete consideration of specific production conditions. The improved route formation algorithm involves 8 steps and is based on the classic ACO algorithm. In contrast to it, it takes into account real production conditions (damaged sections of the roadway,the presence of partial passage of vehicles, traffic jams caused by an emergency, etc.). The rule of the classic ACO algorithm regarding the selection of the next point in the route using the probabilistic-proportional transition of the k-th ant from the i-th to the j-th node (farm producing food raw materials) is proposed, replaced by one that takes into account the state of production conditions (road surface) be-tween individual nodes. This ensures an increase in accuracy and a decrease in the duration of route formation, as well as an increase in the quality of making appropriate management decisions. The obtained results regarding the comparison of the use of algorithms when solving transport problems with a different number of vertices indicate that the proposed algorithm provides a deviation of the total path in the route, which does not exceed 1%. The proposed algorithm reduces the decision-making time by up to 6% in the presence of up to 50 units of vertices, and by 12...15% in the presence of vertices from 51 to 100 units. The improved vehicle routing algorithm can be used in decision-making support systems to plan the procurement of food raw materials on the territory of the community during emer-gencies, which will increase their efficiency.

MODELING OF THE INFLUENCE OF CUTTING MODE PARAMETERS ON THE DURABILITY OF REPLACEABLE CUTTING PLATES WHEN PROCESSING STEAM TURBINE PARTS MADE OF HEAT-RESISTANT CORROSION-RESISTANT STEEL

During the design of the machining technology, one of the important tasks is the choice of cutting modes, at the preliminary stage of the shaping process, which provide a given durability of replaceable cutting plates. In this case, when describing most of the design procedures of the machining process, there are problems associated with the algorithm for choosing the solution method and the response function at the appropriate processing stage. In this paper, as an algorithm for solving the problem, it is proposed to use the methodology of extreme planning of the experiment, which allows to obtain a mathematical model of the investigated multifactorial process. During the implementation of this algorithm in real production conditions, based on a priori information, the research area was selected and the levels of factors with intervals of their further variation in this area were established. Next, a factorial experiment was conducted and its results were processed on the basis of a linear polynomial that takes into account linear effects and interaction effects. As a result of checking the polynomial, a confidence interval was determined for all regression coefficients from three parallel experiments with the same values of factors. At the second stage, the adequacy of the mathematical model itself was evaluated according to the Fisher criterion. Finally, using the logarithm mechanism, a transition was made from the encoded values of the factors in the mathematical model to their natural values and a power function was obtained describing the effect of the cutting mode on the durability of a replaceable tungsten carbide carbide-based carbide plate. The conducted research makes it possible to speed up the procedure for assigning processing modes of workpieces at the preliminary stage in the conditions of existing production, to ensure a given tool durability, which allows to increase the productivity of the shaping process. This technique is the subject of consideration in this work.

Challenges and approaches when realizing online surface inspection systems with deep learning algorithms

Using deep learning in complex online surface inspection systems is challenging due to different framework conditions. First, time restrictions in production are usually fixed in terms of clock rate and response time. Furthermore, these methods need a lot of data, while typically the data situation is thin in the beginning as well as continuously unbalanced: defects occur rarely and thereby providing few example data for learning, while the desired detection rate is 100%. Another important issue is that although defect catalogues exist, they often change, especially when automatic inspection is applied for the first time. This is due to imaging systems usually being able to detect more defects than visual-manual inspection, therefore production, management, and quality assurance usually reiterate their prior defect catalogues. However, data driven methods depend heavily on consistent annotation. Therefore, respective parties must be made aware of this issue on the one hand, on the other hand, annotation and reannotation must be easy and useable by non-experts. Related is the issue of parametrization and traceability. Both are not inherent to neural networks but must be provided to some level to help building trust in machine learning methods. In this paper, we present a quality inspection system that uses deep neural networks for defect detection under real production conditions in wood manufacturing. We will address how we systematically deal with the above issues both in terms of process and algorithm.

Developing the Methodology of Failure Probability for the Rolling Equipment Units and Elements

The safety of basic parts of the rolling equipment is most at risk due to the complex geometrical shape and significant levels of nominal stresses. With a significant mass of such parts and a long production time, the replacement process is accompanied by the need to dismantle the old mill and install a new one. Currently, there are no specialized methods for assessing the risks of failures in relation to the rolling equipment, therefore, it is required to develop new methodological provisions and adapt the existing general methods of risk assessment to real production conditions. Based on the fundamentals of the regulatory document, a methodology for assessing the risks of failures in relation to the rolling equipment has been developed. The roughing stand of the “2000” hot rolling mill for titanium alloy sheet production was chosen as a practical object for assessing the risks of failure. The preliminary analysis of the dangers and their consequences had shown that for most of the elements of the working stand, which perceive the rolling force, as well as for the units and parts of the main drive loaded with the rolling torque, there are dangers that can lead to disruption of the deadlines for fulfilling orders for rolled products. For a numerical assessment of these risks, special calculations were performed.

Моделирование взаимосвязей между входными факторами и выходными показателями процесса внутреннего шлифования с учетом взаимных колебаний инструмента и заготовки

Introduction. In real production conditions, the technological modes recommended in the scientific literature do not reflect the declared qualities, due to the fact that it does not take into account many factors inherent in the process of finishing grinding, for example, its stochastic nature, changes in its dynamic properties, an increase in mutual vibrations of the tool and the workpiece that appear due to changes in the state of the technological system, for example, an increase in vibrations machine tool due to uneven tool wear, etc. All previously developed models have a limited scope of application, it does not take into account the fact that the appearance of vibrations leads to fluctuations in the depth of grinding, with accidental contact of grains with the material being processed, where one group of grains cuts off the material, the other gets into the trace of scratches left by previous grains, etc. This leads to changes in the values of material removal, surface roughness and other parameters of the technological system, which directly affects the accuracy of processing and the quality of the machined surfaces. The purpose of the work is to develop mathematical models that establish the relationship between the processing modes and the current parameters of the contact zone during the fine grinding of pinholes, taking into account the mutual vibrations of the tool and the workpiece. The research methods are mathematical simulation using the basic provisions of the theory of abrasive-diamond processing. Results and discussion. The interrelations between the cutting modes and the current input parameters of the contact zone when grinding pinholes are established, taking into account the mutual vibrations of the tool and the workpiece, which make it possible to determine the parameters of the system at the output to avoid cost losses, including reducing the number of defective products and time costs. Non-stationary mathematical dependences are constructed that allow determining the cutting modes during the implementation of the grinding cycle, taking into account the magnitude of relative vibrations and the initial phase. It is established that instead of a steady process, harmonic oscillations are observed caused by deviations in the shape of the circle, the intensity of tool wear and other factors, all of the above has a significant impact on the quality of the machined surface. The obtained models are universal for various characteristics of the tool, however, for a more adequate description of the process, mathematical dependencies are needed that take into account the wear of the tool on various binders, which is the task of further research.

Estimation of alfalfa fall dormancy using spaced plant and sward trials across multiple environments

AbstractBackgroundAlfalfa is a globally important forage crop. Cultivars are characterized by fall dormancy (FD). FD affects biomass yield and winter survival and is used to identify appropriate growing regions of cultivars. It has historically been assessed by measuring the natural height of regrowth in autumn of spaced plants in the field. Because commercial alfalfa is normally grown as a solid planted sward, FD could be different if plants were grown under real production conditions. The objective of this experiment was to assess whether FD ratings obtained from swards were similar to those obtained on spaced plants.MethodsWe evaluated 20 alfalfa cultivars in field trials established in 2015 at five locations in the United States. We harvested the trials in early autumn and measured regrowth plant height approximately 3 weeks later in 2015 and 2016.ResultsAutumn plant height responded as expected for the established check cultivars in all locations. Fall dormancy ratings for cultivars under both management systems were highly correlated.ConclusionsEstimating FD from spaced plant height measurements in autumn is very robust, and using height data from sward plots gives equivalent results to that measured in spaced plant nurseries. This finding has many practical advantages.

Novel Corrugated Long Period Grating Surface Balloon-Shaped Heterocore-Structured Plastic Optical Fibre Sensor for Microalgal Bioethanol Production.

A novel long period grating (LPG) inscribed balloon-shaped heterocore-structured plastic optical fibre (POF) sensor is described and experimentally demonstrated for real-time measurement of the ultra-low concentrations of ethanol in microalgal bioethanol production applications. The heterocore structure is established by coupling a 250 μm core diameter POF between two 1000 μm diameter POFs, thus representing a large core-small core-large core configuration. Before coupling as a heterocore structure, the sensing region or small core fibre (SCF; i.e., 250 μm POF) is modified by polishing, LPG inscription, and macro bending into a balloon shape to enhance the sensitivity of the sensor. The sensor was characterized for ethanol-water solutions in the ethanol concentration ranges of 20 to 80 %v/v, 1 to 10 %v/v, 0.1 to 1 %v/v, and 0.00633 to 0.0633 %v/v demonstrating a maximum sensitivity of 3 × 106 %/RIU, a resolution of 7.9 × 10-6 RIU, and a limit of detection (LOD) of 9.7 × 10-6 RIU. The experimental results are included for the intended application of bioethanol production using microalgae. The characterization was performed in the ultra-low-level ethanol concentration range, i.e., 0.00633 to 0.03165 %v/v, that is present in real culturing and production conditions, e.g., ethanol-producing blue-green microalgae mixtures. The sensor demonstrated a maximum sensitivity of 210,632.8 %T/%v/v (or 5 × 106 %/RIU as referenced from the RI values of ethanol-water solutions), resolution of 2 × 10-4%v/v (or 9.4 × 10-6 RIU), and LOD of 4.9 × 10-4%v/v (or 2.3 × 10-5 RIU). Additionally, the response and recovery times of the sensor were investigated in the case of measurement in the air and the ethanol-microalgae mixtures. The experimentally verified, extremely high sensitivity and resolution and very low LOD corresponding to the initial rate of bioethanol production using microalgae of this sensor design, combined with ease of fabrication, low cost, and wide measurement range, makes it a promising candidate to be incorporated into the bioethanol production industry as a real-time sensing solution as well as in other ethanol sensing and/or RI sensing applications.

Toward Calenderability of High‐Energy Cathode based on NMC622 during the Roll‐to‐Roll Process

For the economical production of high‐quality lithium‐ion batteries, a comprehensive understanding of all processing steps under real production conditions, especially in the electrode‐manufacturing step, is mandatory. It has been shown that calendering of the cathode has a significant impact on the electrode quality and hence affects their subsequent processability in the battery production. Undesirable electrode deformation induced by the calendering process may lead to unnecessary wastage during the roll‐to‐roll process. To increase the yield rate of high‐energy electrode production under industrial‐oriented conditions, an extensive recipe evaluation by applying mixture design methods has been carried out on the lab scale. It has been shown that the inactive carbon black/PVDF phase as well as the amount of SFG6L in the electrode formulation plays an important role in the calendering processability of the high‐energy NMC622 cathode. From the statistical data analysis, an optimized recipe has been proposed and afterward validated at the research production line under industry‐relevant conditions. A significant reduction of the scrap rate caused by the calendering process is observed after optimizing the recipe due to its better calenderability.

Modeling and simulation of the furniture manufacturing and assembly process in the arena simulation software

The article describes issues related to creating discrete simulation models for the implementation of the furniture manufacturing and assembly process in a furniture company. The methodology of the manufacturing system analysis was presented, which is aimed to support the appropriate approach to the construction of simulation models. The scope of the work includes the technological identification of the furniture manufacturing and assembly process in real production conditions, on the basis of which the appropriate simulation model was built. The course of the process was analyzed in the Arena software on the basis of a computer simulation based on reports. As a result of the simulation of the manufacturing process with the use of information from report of usage, an area for improvement was located. The re-analysis of the material flow made it possible to propose a change in the input parameters for the simulation model in the indicated area. The results of the second simulation show significant changes in the effective use of workstations and increase in the efficiency of the production line. In practice, it can be the basis for introducing simulated changes in the production system.

Modeling the thermal state of a strip during laminar cooling

A local physical and mathematical model of the thermal state of the strip during laminar cooling has been developed. The mathematical model is implemented as a software product. The software product was tested under real production conditions based on a comparison of actual and calculated strip temperatures when passing through the first group of coilers after laminar cooling. The standard deviation (1.15 °C), average relative error (1.6%), relative errors (do not exceed 3.7% or 28 °C) were determined. Calculation criteria confirm the adequacy of the developed mathematical model.

Research Regarding Correlation between the Assured Health State for Laying Hens and Their Productivity

Predictions show the possibility of banning birds’ rearing in batteries. From this reason, we aimed to study the welfare conditions assured to birds accommodated in lofts in comparison with those reared in improved batteries. The research targeted ISA Brown hybrids monitored over a period of 25–55 weeks. The batches were represented by birds that were differently reared in halls provided with lofts compared to with improved batteries. The research was carried out in real production conditions. Biochemical indicators were determined, using a BA 400 analyzer produced by BioSystems, as well as quantitative ones using specific formulas based on productions, consumptions, and batch outputs. A cumulated production of 199.24 eggs/week/head was realized in the loft, versus 199.98 in the battery, at a mean laying intensity of 91.82% and 92.17%. Batch output was 4.14% (loft) and 2.98% (battery). Mean consumption registered a level of 122.20 g m.f./head/day for birds in the loft and 115.87 g for the ones from the battery, and feed conversion index was 133.09 g m.f./egg, compared to 125.69. The aviary system ensures optimal conditions to express the birds’ natural behaviors, with a positive impact on the metabolic functions, resulting in a good state of health and high productive levels, comparable to those of birds exploited in batteries.

Non-Aerated Common Nettle (Urtica dioica L.) Extract Enhances Green Beans (Phaseolus vulgaris L.) Growth and Soil Enzyme Activity.

One of the limiting factors in organic farming is the scarcity of allowed fertilizers and chemicals for plant protection. Plant and compost extracts are a promising solution for fertilization because of their positive effect on plant growth and soil microbial activity. Nettle extract was already successfully applied to some vegetables. Not-aerated nettle extract, obtained from dry nettle leaves, was applied in experiments with green beans in a quantity of 1 L per pot at two-day intervals was studied. A three-factorial experimental design was applied with two soil types (brown-Calcic Gleysol and red-Eutric Cambisol), soil disinfection with dazomet or not, and irrigated with nettle extract or water. Nettle extract application increased all above-ground traits; plant height, leaf area, flower buds, shoot dry weight at flowering, pod length, pod diameter, and shoot dry weight at harvest by 49%, 66%, 43%, 36%, 11%, 9%, and 37%, respectively, the root length at harvest by 59%, total yield by 48%, soil respiration by 91% and 74% in two soil types, and alkaline phosphatase by 30%. Dehydrogenase activity was enhanced by nettle extract application on red soil, while nettle extract application had no effect on root nodulation. The nettle extract application benefits in green bean organic production were attributed to the nutrients and other components present in the extract and not to nitrogen fixation. The optimization of the dose of the extract and experiments in real conditions of green bean production would be the next step toward the implementation of nettle extract as an organic fertilizer.

Evolution of the grain structure of metals and alloys under severe plastic deformation: continuum models

Products made of metals and alloys with a fine-grained structure, which have high physical, mechanical and operational characteristics, are becoming increasingly in demand in many technical and technological fields. The most common and efficient technologies for the production of parts from this class of materials are various processes of severe plastic deformation (SPD) (in general practice, at low homologous temperatures). At the same time, to achieve high degrees of deformation, a significant part of metals and alloys require increased processing temperatures, undergo significant heating during deformation processes, which may be accompanied by changes in the grain and subgrain structure due to recovery and recrystallization processes. An empirical approach to the development of SPD modes that ensure the formation of the necessary grain structure requires huge time and financial costs, and therefore considerable attention is paid by researchers in the field of solid mechanics and metal forming to approaches and methods of mathematical modeling. In connection with the foregoing, the number of publications on this subject has been intensively growing in recent years. The currently known models differ significantly in their approaches, the depth of penetration into the physics of processes, and the scope of consideration. The proposed brief review is focused on a qualitative analysis of works on this topic, a preliminary classification of existing models according to their purpose, versatility, and functionality. It seems possible to single out the two most common approaches to describing the change in the grain structure in the processes of thermomechanical processing of metals and alloys: continual (in most cases, single-level) and multilevel, based on the introduction of internal variables and physical theories. This review is devoted to the consideration of publications focused on the first of these approaches. Until now, the most common are macrophenomenological continuum models based on the analysis of experimental data conducted both in laboratories on macrosamples and in real production conditions. Models of this class are usually formulated in the form of operator relations over field quantities, they are relatively easy to implement due to their easy “embedding” into widely used commercial software packages, but they require significant costs for experiments to identify models, they are characterized by a low degree of versatility. Continuous theories are relatively less common, but still often used. These theories are based on the description of physical mechanisms and the evolution of the structure of metals and alloys in terms of continuum variables.

Особенности проектирования микросхем, выполненных по глубоко-субмикронным технологиям

Noise and signal integrity are important factors influencing the design process of microcircuits made using submicron technology. Currently, there is some difference in what design engineers can design and what can be manufactured with the right level of quality and reliability. Therefore, it is necessary to create a fundamentally new methodology for verifying VLSI projects with deep submicron design standards. In order to calculate the percentage of good chips manufactured, it is required to identify vulnerable effects and phenomena from the point of view of submicron technology. In this paper, the effect of noise on various types of microcircuits is studied and recommendations are given for limiting noise. One of the options for achieving the optimal balance between noise, noise immunity and microcircuit parameters is to add margins when calculating the VLSI parameters. The paper shows that VLSI projects with nanometer topological norms must undergo an additional process of verifying the parameters and functioning in general before issuing information for the production of photomasks. Verification requires the use of an integrated set of software tools that are certified in real production conditions.

Experimental Research and Reduction of Vibration of Pumps of Industrial Enerprises

The harmful vibration effects of industrial pumps and ways to reduce vibration were considered. The causes of pump vibration were described. The results of experimental studies of pump vibration in real production conditions were analyzed on the example of industrial enterprises. It was concluded that the most significant fluctuations are observed in the low-frequency range. Methods and devices for reducing the vibration of pumps were studied.