Rational Set Research Articles

Развитие теории и принципов планирования многономенклатурных технологических процессов механообработки и сборки

Instructional guidelines for planning a multiproduct manufacturing activity (MA) for machining and assembly aimed at solving currently existing problems of machining industries process design, i.e. subjectivity of making design decisions, insufficient automation, and inability of the observing of current production situation are presented. The objective reasons for the need to improve approaches to the development of MA are the long cycle of the process design period, the low quality of the processes operation, and the impossibility to adjust MA at the implementation stage. The main structural elements of multiproduct manufacturing activity planning are described. Based on a systematic approach, all stages of work on technological support of production systems are combined, making possible to use the information arrays of data on the real state of the production system and operational information on production tasks in a short time frame. The results of theoretical work provide for the process of making MA as a system that combines the design and implementation of technology, taking into account the impact of changes in the production situation. In the process of approbation and use of the presented methodological approaches, significant areas of research were identified, smoothing away difficulties connected with the performance targets, enabling the development path of the system. Among them: the interaction with the design preparation of production; detailing data on the initial workpieces in connection with the choice of the MA structure and the appointment of a rational set of technological equipment; determining the requirements for technological equipment, focused on ensuring the flexibility of their use; determining the correlations between the multiple-path design of parts manufacturing process and the requirements for accuracy indicators in the assembly of products. The developed formalized models for the implementation of the stages of technological preparation of machining industries are a background for full automation of MA design and highly efficient functionality of machine-building complexes.

Multi-parameter and multi-objective optimization of dual-fuel cell system heavy-duty vehicles: Sizing for serial development

Dual-fuel cell hybrid system provides an attractive propulsion option in transportation, especially for heavy-duty vehicles. However, the larger vehicle weight improves the sensitivity of power demand to road conditions and vehicle handling, making it a challenge to realize reasonable sizing. The scope of this work is to demonstrate a multi-objective and multi-parameter optimization for the serial development of the heavy-duty vehicle, powered by a dual-fuel cell hybrid system. Toward this end, a comprehensive modeling is presented combining the degradation model of the FC system and the battery system. The Pareto theory is introduced to evaluate the three-dimensional objectives involving the equivalent hydrogen consumption, the mass goal, and the vehicle dynamic, which is derived from different six-dimensional parameters under a dual-layer optimization approach. The brute force approach is not applicable in the presence of the curse of dimensionality arising from multi-parameter optimization. The proposed methodology offers a viable approach to acquiring rational sets of sizing solutions in the optimization space with high-dimensional parameters. Considering the serialization of products, the improved solution and the corresponding performance upper limit have be determined according to the proposed methodology under different weight levels as well.

Upcycling of Graphite Anodes via Tailored Solvent Treatment

To achieve a truly closed-loop direct recycling process for lithium-ion batteries, all component materials must be recovered. To date, direct recycling method development has primarily focused on the high-value transition-metal cathode materials, while the inherently lower-value graphite has been challenging to recover in a cost-effective manner. However, end-of-life graphite contains a unique engineered value due to the presence of the solid electrolyte interphase (SEI). Growth of the SEI during the cell’s active lifetime stabilizes the electronically reactive graphite surface through an irreversible consumption of Li, and thus necessitates both excess lithiation of the cathode and a costly and time-intensive formation procedure during manufacturing. An optimized pre-formed SEI that capitalizes on existing SEI components from end-of-life batteries has the potential to significantly reduce cathode lithiation requirements and eliminate the critical bottleneck of formation cycling during cell remanufacturing. Further, retaining Li at the anode obviates the need for a separate Li leaching and recovery step, improving the overall efficiency of the direct recycling line. In this work, we present a novel approach to “upcycling” spent graphite through use of tailored chemical treatment to remove adverse (i.e., highly resistive and/or poorly passivating) SEI species while retaining beneficially passivating components. We have explored a rational set of solvents spanning a range of polarity, proticity, and molecular size to evaluate structure-property-performance relationships between applied solvent(s), removed and remaining SEI species, and electrochemical response of the resulting graphite product. Further, we have developed and optimized a robust and holistic analysis procedure that couples symmetric-cell electrochemical testing, multi-modal materials characterization, and advanced electrochemical modeling. These analysis results inform a set of correlative metrics for graphite performance relative to both solvent properties and upcycled SEI composition. We demonstrate effective tunability in the residual SEI composition by varying solvent identity and concentration, and report on several promising solvent systems that achieve comparable performance to pristine graphite. Figure 1

Container drayage problem integrated with truck appointment system and separation mode

Growing demand for seaborne trade has exacerbated the challenges faced by drayage operators in inland container transportation. In some cases, drayage operators must make truck scheduling decisions and book periods for trucks to visit terminals daily. This paper considers the appointment system and separation mode in container drayage problem, which consists of delivery and pickup transportation tasks for empty and full containers. A mixed-integer linear programming model is developed to minimize the total truck operating time while solving the truck scheduling problem, the empty container allocation problem, and the appointment problem. Another key feature of the model is considering the temporal constraints between tasks from a more realistic perspective. Due to the complexity of the problem, it is not practical to obtain exact solutions for large instances. Therefore, we complete the implementation of a new genetic algorithm (GA) that introduces a topological sort tailored to this problem. Several experiments and analyses are used to demonstrate the correctness of the proposed model as well as the efficiency of the algorithm. The findings indicate that, when compared to traditional mode, separation mode can reduce total truck operating time by an average of 29.4%. The total truck operating time difference between the two modes shows an overall positive trend if the task size increases. In addition, a rational setting of the appointment system will have a beneficial effect on truck scheduling. The decision on the selection of periods and the increment of each quota is crucial in optimizing the setting of the appointment system to reduce the total truck operating time for the mutual benefit of both terminals and drayage operators.

Rational sets in virtually abelian groups: Languages and growth

In this paper, we generalise and unify the results and methods used by Benson, Liardet, Evetts, and Evetts &Levine to show that rational sets in a virtually abelian group G have rational (relative) growth series with respect to any generating set for G . We prove equivalences between the structures used in the literature and establish the rationality of important classes of sets in G : definable sets, algebraic sets, conjugacy representatives, and coset representatives (of any fixed subgroup), among others. Furthermore, we show that any rational set, when written as words over the generating set of G , has several EDT0L representations.

Research on Summer Indoor Air Conditioning Design Parameters in Haikou City: A Field Study of Indoor Thermal Perception and Comfort

Escalating global climate change and the intensification of urban heatwaves have led to an increase in summer air conditioning cooling energy consumption. This phenomenon is particularly critical in tropical regions, as it may trigger an energy crisis. The rational setting of indoor thermal design parameters can help conserve energy to the maximum extent while ensuring thermal comfort for occupants. This study selected Haikou City, a unique tropical city in China, as the research location. Indoor environment measurements and a questionnaire survey were conducted with participants, and the outdoor thermal environment sensitivity, population attributes and differences in thermal sensation, thermal neutral temperature, and comfort range were calculated and analyzed. The following results were obtained. Based on the overall population, long-term residence, and temporary residence classification, the indoor thermal comfort needs of residents in tropical cities in Haikou were effectively identified. The actual thermal neutral temperature of the overall population is 25.7 °C, and 90% of the acceptable thermal comfort temperature range is 23.2 °C–28.0 °C. The actual thermal neutral temperature of the regular residents is 27.3 °C, and 90% of the acceptable thermal comfort temperature range is 23.3 °C–31.4 °C. The actual thermal neutral temperature of the temporary population is 25.5 °C, and 90% of the acceptable thermal comfort temperature range is 23.0 °C–28.0 °C. These research results have an important reference value for improving the setting of the temperature of air conditioning in tropical areas in summer and further reducing energy consumption, which is conducive to sustainable development.

Dynamic Projection Method of Electronic Navigational Charts for Polar Navigation

Electronic navigational charts (ENCs) are geospatial databases compiled in strict accordance with the technical specifications of the International Hydrographic Organization (IHO). Electronic Chart Display and Information System (ECDIS) is a Geographic Information System (GIS) operated by ENCs for real-time navigation at sea, which is one of the key technologies for intelligent ships to realize autonomous navigation, intelligent decision-making, and other functions. Facing the urgent demand for high-precision and real-time nautical chart products for polar navigation under the new situation, the projection of ENCs for polar navigation is systematically analyzed in this paper. Based on the theory of complex functions, we derive direct transformations of Mercator projection, polar Gauss-Krüger projection, and polar stereographic projection. A rational set of dynamic projection options oriented towards polar navigation is proposed with reference to existing specifications for the compilation of the ENCs. From the perspective of nautical users, rather than the GIS expert or professional cartographer, an ENCs visualization idea based on multithread-double buffering is integrated into Polar Region Electronic Navigational Charts software, which effectively solves the problem of large projection distortion in polar navigation applications. Taking the CGCS2000 reference ellipsoid as an example, the numerical analysis shows that the length distortion of the Mercator projection is less than 10% in the region up to 74°, but it is more than 80% at very high latitudes. The maximum distortion of the polar Gauss-Krüger projection does not exceed 10%. The degree of distortion of the polar stereographic projection is less than 1% above 79°. In addition, the computational errors of the direct conversion formulas do not exceed 10−9 m throughout the Arctic range. From the point of view of the computational efficiency of the direct conversion model, it takes no more than 0.1 s to compute nearly 8 million points at 1′×1′ resolution, which fully meets the demand for real-time nautical chart products under information technology conditions.

The Politics of Prevention and Government Responses to Homelessness

Recently, the logic of public health prevention has found a foothold in research and advocacy about homelessness. From a commonsense perspective, the prevention of a social problem like homelessness is an objectively positive aim. However, in the realm of social and health policy, the concept of prevention is not simply a common-sense word. It is part of a wider set of rationalities and technologies of governance which operate in and through the institution of public health. Research demonstrates that state-driven interventions designed to advance the health of a population often pose problems for particular groups. Prevention efforts, and their differential effects, thus have the potential to illuminate how state-interventions pursued with the objective of safe-guarding the public in general may simultaneously exacerbate specific structural and systemic forms of inequality. In this article, we probe the ethical, empirical, and political dimensions of state-driven responses to the coronavirus disease of 2019 (COVID-19) public health crisis, surfacing some of the ways these interventions posed problems for people who are homeless and experience intersecting health and socio-political disparities. From this vantage point, we then look critically at moves to frame homelessness as a public health crisis, as well as government efforts to prevent homelessness by drawing on public health rationalities. Although our focus is homelessness prevention, as constructed and pursued by governments, our analysis is inspired by critical public health scholarship that challenges the apparent impartiality of prevention as a central logic and set of practices in public health contexts.

Evaluation Model Construction of School-Enterprise Cooperation Innovation Ability Based on Big Data Analysis

Abstract This study analyzes SCIE papers published by 39 universities as a substantial big-data sample, employing latent class analysis to explore the characteristics of university-enterprise cooperation in Chinese institutions. It identifies five categorical attributes to construct a latent class model. This paper integrates hierarchical analysis with fuzzy mathematics to develop a comprehensive fuzzy evaluation model. By organizing and layering the factors, a rational set of indicators is established, and a hierarchical analysis structure is constructed. Utilizing a judgment matrix, the study calculates the importance rankings of all indicators, thereby highlighting the significant influence of the factors. Empirical results indicate that the model achieves optimal fit with five latent categories. Within the five primary indicators for evaluating the innovation capability of university-enterprise cooperation, the weight of innovation outcomes is the highest at 0.24, followed by industrial innovation at 0.22. The analysis reveals a regional imbalance in university-enterprise collaboration across the eastern coastal area, with Guangdong achieving the highest rating of 84.03, closely followed by Jiangsu. In assessing the innovation capability of university-enterprise cooperation in Guangdong's applied universities, the overall scores for universities categorized as B, C, and D are 3.641, 3.522, and 3.409, respectively. Notably, the scores for R&D investment intensity and Chinese patent applications are relatively low, suggesting these areas require enhancement to bolster support and development, thereby improving university-enterprise cooperation and innovation capabilities.

Preliminary Exploration of Rational Settings for Sponge Airport Indicators in the Context of Low Carbon -- Taking Baiyun Airport as an Example

Sponge city is an important means of urban stormwater management, and it is also the core concept of green and low-carbon ecological landscape construction.Currently, the rainfall and flooding problems of airports are becoming more and more obvious, and the construction of "sponge airports" is getting more and more attention. However, considering the operational needs of airports, the existing conventional sponge construction ideas cannot be directly applied to airport construction. How to set up a set of reasonable indicators that not only guarantee the safe operation of airports but also meet the requirements of the existing sponge city construction is one of the problems that need to be solved in the process of airport sponge city construction. Taking the third phase expansion project of Guangzhou Baiyun Airport as an example, the design principles of focusing on safety, adapting measures to local conditions, and meeting the overall standards, from the overall consideration of the airport, combined with the land use of each functional zone of the airport, reasonably set the sponge index, so as to provide a reference for the construction of "sponge airport", in order to promote the sustainable development of green and low-carbon construction.

Characteristics of operational control reliability of aircraft functional systems and avionics suites

The operational control system (OCS) of civil aircraft (A/C) airborne equipment is an important component of its technical operation system (TOS). Operational control is an integral part of the technical operation process. It makes it possible to assess the technical conditions (TC) of the objects to be monitored in various states of airborne equipment operation, aircraft preparation for flight, various types of maintenance and recovery. The main property of operational control is the reliability of control. The key task of operational control is not only to determine the type of technical condition, but also to quantify the correctness or erroneousness of decision-making. Control reliability characteristics (CRC) are quantitative indicators of the degree of objectivity in decision-making. Depending on the level of task details, it is necessary to distinguish the control reliability characteristics of units, functional systems (FS) and avionics suites for various means of operational control: built-in test equipment (BITE), on-board self-contained, ground-onboard and ground systems. The choice of the control reliability characteristics is based on the system analysis and the mathematical apparatus of logic, probability theory and mathematical statistics. Rational sets of technical states and decision-making about the technical conditions of functional systems and avionics suites are formed. Based on these sets, three groups of control reliability characteristics were identified. The first group consists of conditional probabilities of transitions in the operational control process under various types of control. The second group consists of unconditional probabilities of transitions in the operational control process under various types of control. The third group consists of a posteriori decision-making probability in the operational control process under various types of control. Analytical dependences for calculating the control reliability characteristics of three groups for functional systems and avionics suites and relationships between them are determined. The air-conditioning system was used to calculate the reliability of the control.

Principles of formation of modular technologies of enteral nutrition products

Introduction. Enteral nutrition products (EP) are represented on the market by a wide range of imported products, the technology and formulations of which are unique and are objects of intellectual property of foreign scientific centers. The application of a unified methodological approach to the design of EP products will make it possible to transfer this process from an empirical to a scientifically based plane.Purpose of research is to create a rational set of technological solutions for the production of specialized EP products based on the principles of modularity, taking into account the cascade of technological qualitative and quantitative transformations.Materials and methods. Digital matrices of patient conditions, EP products and ingredients were used as materials. The main research method was advanced digital profiling, taking into account the transformation of nutrients in the production process.Results. According to the formed matrices of the chemical composition of imported EP products, the criteria relationships of their digital profiles and state profiles were established. Based on the principles of food combinatorics and digital profiling, an algorithm for an improved approach to the design and production of EP is proposed. A generalized modular technology for the production of EP products has been developed and its variability has been proved without changing the structure due to the combinatorial versatility of each of the set of models. The degree of its available combinatorial variability has been established, which is functionally dependent on the number of combinatorially manipulated ingredients, taking into account all possible k-component compositions. The required set of formulations of EP products is a set of solutions in terms of design with the possibility of determining the vector of tasks to be solved.Conclusions. The obtained research results can be applied in the food industry in terms of unified production of specialized products.

PRODUCTION TECHNOLOGY OF VEGETABLE PROTEIN-VITAMIN PASTE

The problem of providing the population of Ukraine with products of animal origin is currently very urgent, because barely two-thirds of the population is supplied with meat products, and a little more than half with dairy products. Traditional harvesting technologies cannot provide a sufficient amount of highly nutritious fodder, mainly due to significant losses during the implementation of technological operations. One of the ways to increase the intensity of fodder production is the fractional harvesting of high-protein green plants with the allocation of protein-vitamin concentrate as the main type of fodder. The analysis of the latest research and publications showed that currently there are no single, scientifically based recommendations regarding the rational set of machines and mode parameters of their operation when implementing this technology. Based on the results of previous studies, an experimental set of machines was formed to implement the technology of wet fractionation of alfalfa. The technological scheme includes such lines as dosing, disintegration (shredding) and wet fractionation of green plants, a line for coagulation of green juice, a line for separating the suspension obtained as a result of coagulation, a line for drying vegetable protein-vitamin concentrate and making pellets from it. Modeling the operation of the specified complex of machines allowed to determine the rational parameters of the operation of most of them, to outline the ways of further improvement of the nomenclature of machines, their location in technological lines, etc. For example, to increase the productivity of the filtration operation of the suspension obtained after coagulation of the green juice of alfalfa, it is advisable to direct it to special tanks for settling before sending it to the filter press, which will allow to increase the output of the protein-vitamin concentrate after filtering. The conducted modeling of the experimental complex of machines for the implementation of the fractional technology of harvesting alfalfa with the production of protein-vitamin concentrate showed the prospects of this technology for the development of the fodder industry.

Оптимізація електрогідравлічного розподільника з незалежним керуванням потоків

The hydraulic drive is one of the most common types of drives used on mobile working machines of various purposes, including machines that are intended for performing load and unloading operations.
 The quality of work operations of such machines largely depends on the characteristics of the hydraulic equipment, which is part of the hydraulic drive, in particular depends on characteristics of valves.
 The purpose of the work is investigation of the impact of the constructive parameters of proportional electro-hydraulic valve with independent flows control on dynamic processes in the system and to establish the optimal combination of this parameters.
 The proportional electro-hydraulic valve contains two independent elements to control the flows at the inlet and outlet of the hydraulic motor independently of each other. This increases the degree of controllability and makes it possible to perform work operations due to the accumulated energy of the object, for example, the potential energy of a load raised to a certain height, which is quite relevant for mobile working machines that perform loading and unloading operations.
 The work of the valve, which is considered is determined not only by certain values of its constructive parameters, but also their corresponding sets. Since the degree of influence of a certain structural parameter on the characteristics of the work of the valve is not unambiguous and may be interconnected with other structural parameters, so to determine in advance the rational set of parameters that would provide the desired characteristics is extremely difficult, and in some cases practically not possible.
 That is why optimization was used to determine the values of structural parameters.
 One of the first stages of the study was to establish the degree of influence of the set of values of constructive parameters on dynamic and static characteristics. Applying the proposed influence coefficient, the constructive parameters that have the largest influence on the dynamic characteristics have been determined.
 Using the LP-search method, optimization was carried out, and a set of parameters was established that provide improved dynamic characteristics.

On periodic alternate base expansions

For an alternate base β=(β0,…,βp−1), we show that if all rational numbers in the unit interval [0,1) have periodic expansions with respect to the p shifts of β, then the bases β0,…,βp−1 all belong to the extension field Q(β) where β is the product β0⋯βp−1 and moreover, this product β must be either a Pisot number or a Salem number. We also prove the stronger statement that if the bases β0,…,βp−1 belong to Q(β) but the product β is neither a Pisot number nor a Salem number then the set of rationals having an ultimately periodic β-expansion is nowhere dense in [0,1). Moreover, in the case where the product β is a Pisot number and the bases β0,…,βp−1 all belong to Q(β), we prove that the set of points in [0,1) having an ultimately periodic β-expansion is precisely the set Q(β)∩[0,1). For the restricted case of Rényi real bases, i.e., for p=1 in our setting, our method gives rise to an elementary proof of Schmidt's original result. Therefore, even though our results generalize those of Schmidt, our proofs should not be seen as generalizations of Schmidt's original arguments but as an original method in the generalized framework of alternate bases, which moreover gives a new elementary proof of Schmidt's results from 1980. As an application of our results, we show that if β=(β0,…,βp−1) is an alternate base such that the product β of the bases is a Pisot number and β0,…,βp−1∈Q(β), then β is a Parry alternate base, meaning that the quasi-greedy expansions of 1 with respect to the p shifts of the base β are ultimately periodic.

Tectonics and gravity field structure of Central Kazakhstan

Purpose. Identification of the nature of the manifestation of tectonic elements of different ages in Central Kazakhstan in gravitational fields based on the results of the calculation of regional, intra-crustal and local transformants. Methodology. Synthesis and analysis of the data on integrated interpretation and modeling of gravitational, geomagnetic, geothermal fields, the latest movements of the Earth’s crust and parameters of the seismic regime, tectonics and stratigraphy of rocks. Findings. Regional, intra-crustal and local heterogeneities in the lithosphere manifest themselves differently in blocks of Precambrian rocks, Early and Late Caledonides, Early and Late Hercynides. They may be associated with the processes of Paleozoic intracontinental rifting, with the rise of mantle matter and its emplacement into the Earth’s crust, followed by the manifestation of Late Paleozoic orogenesis, doubling of the thickness of the Earth’s crust, outpourings of magmatic formations. Originality. It is established that large gravitational minima are distinguished in areas with Hercynian folding, characterized by abnormally high amplitudes in the movement of the Earth’s crust. In the regions of the Caledonian folding, the values of gravity field anomalies of intermediate intensity and increased amplitudes of the latest movements of the Earth’s crust are manifested. Areas with Pre-Paleozoic folding have relative maxima of gravitational anomalies and minimum values of the latest movements of the Earth’s crust. Earthquake sources are concentrated in the consolidated crust at the junction of areas with different ages of basement consolidation, in gradient zones of geothermal, geomagnetic and gravitational anomalies. According to the variations of the intra-crustal transformant, it was found that a wide range of changes in the values of the gravitational field corresponds to areas with minimal temperature values, whereas in areas with increased temperature values, the range of changes in the values of gravity anomalies is reduced. The distribution of the local transformant of the gravitational field indicates the existence of highly variable anomalies, which reflects the high-frequency gravitational effect of near-surface objects of the Earth’s crust. Practical value. The distribution of inhomogeneities in the lithosphere with various density, geomagnetic and geothermal anomalies of geophysical fields, the nature of the seismic regime and the latest movements of the Earth’s crust predetermined the formation of geostructures with different types of mineralization, each of which is recommended to be searched and explored by a specific rational set of geophysical methods.

Plowing operation: labor productivity and specific operating costs. Part 1. Multifactor simulation of plowing operation

One of the most important problems in grain production in the Republic of Belarus is increasing labor productivity, which is 4–5 times less than labor productivity in the EU countries. A great influence on labor productivity and specific operating costs is exerted by energyand material-intensive operations, such as plowing and harvesting. The main patterns of the plowing operation, which is a complex technical system, is connected with the use of a large volume of agrotechnological, technical, operational, resource and economic information (operation duration, working length of the harrow, physical and mechanical properties of soil, depth of treatment, permissible interval of the unit speed, fuel and energy, engine power and traction characteristics, width of the unit, economic indicators, etc.) are considered. Currently, as a result of introduction of computer mathematics systems, there are effective methods available for studying complex technical systems, allowing for multi-factor modeling and multi-criteria optimization of the production processes and formation of a set of machines by system analysis. A prerequisite for a complete and comprehensive description of the functioning of a complex technical system is the presence of conflicting optimization parameters, as well as a complete set of independent control factors significantly affecting these parameters. A distinctive feature of the proposed method is to determine not one optimal solution, but a set of Paretooptimal solutions, giving the producer new opportunities of choice when organizing the production processes, increasing the efficiency of plowing operation and, consequently, the profitability of grain production in general. Therefore, increasing productivity at permissible specific operating costs through the formation of a rational set of machines and modes of its operation under specific conditions of production is an important scientific and engineering task. A mathematical illustration of the method is provided for natural-production conditions of the Republic of Belarus.

Formation of Rational Sets of Machines for Excavation Work in Urban Areas

The study is aimed at developing a tool for the formation of a rational set of machines for excavation work in urban areas. The instrument to be developed will affect the main project parameters, such as the project cost and term of implementation. An expert survey was launched among the leading specialists of the construction industry to make a set of significant parameters and identify the weighting ratio, since both are required to select the machines for rational sets designated for excavation work in urban environments. The equation of multiple regression was solved to determine the extent of significance by calculating Fisher’s ratio. This equation shows that significant parameters are inter-related and can be used in this method. A method for making a rational set of machines, designated for the performance of excavation work in urban environments, has the following stages: at the first stage, the choice of the necessary excavation work at the construction site is made; at the second stage, limitations, arising at the site, are introduced; at the third stage, the minimum number of major machines is determined; at the fourth stage, a rational set of machines is made step by step. If implemented, this study demonstrates the high economic efficiency of the proposed method of expanding excavation work in urban environments. The study shows that the use of a mathematical model will boost the project’s success, as it demonstrates the critical factors of risk at the initial stage of the life cycle of a construction project.

Theoretical and Experimental Verification of Organic Granular Fertilizer Spreading

Due to the continuous creation of organic granular fertilizers of the new composition, there is a lack of knowledge about their properties and the influence of the norm on spreading efficiency. To increase the efficiency of the use of granular organic fertilizers, their spreading aims are to properly choose the most rational spreading parameters and fertilizer norms, considering the characteristics of the fertilizer. To determine this quickly and with lower costs, various theoretical models and computer programs are used to study the dynamics of fertilizer spreading. The purpose of this work was to perform theoretical and experimental comparative studies of the influence of the characteristics and dosage norms of granular fertilizers of poultry manure on the spreading efficiency. During the research, the physical properties of granular poultry manure fertilizers were determined, which have an impact on the quality of spreading. Experimental studies of fertilizer spreading were carried out using two centrifugal spreaders with the same parameters (Amazone ZA-M-1001 (spreading dosage norm, 200 kg ha−1 and 400 kg ha−1; driving speed, 10 km h−1) and ZA-M-1201 (spreading dosage norm, 600 kg ha−1, 800 kg ha−1, and 1000 kg ha−1; driving speed, 5 km h−1)). Before the fertilizer was spread, measurements were made of the flow rate of the spreadable fertilizer through one bunker shutter. Fertilizer application simulations were performed using the discrete element simulation program EDEM. Research has shown that spreading the studied granular fertilizers at the dosage norm of 600 and 800 kg ha−1 allows for the future expansion of the limits of spreading research using a spreading simulation. The most important directions of research would be the research of the spreader vanes’ shape, length, and rational settings positions, using the standard commonly used centrifugal spreader, after making small modifications of the spreader, to achieve that the spreader could spread larger norms of fertilizer or drive faster during spreading.

The ontogenesis of human capital in an enterprise

The management of the company traditionally faces the task of increasing the effectiveness of human capital (HC), its timely transformation, and the early accumulation of the necessary human resources. In this regard, the purpose of this work was to establish a rational set of transformations that HC goes through from its inception to the end of its existence. The human capital of an enterprise in the work is understood as a combination of the corporate human capital of the organization and the individual human capital of its employees. The methodological basis of the study was the four-component system economic theory, the evolutionary theory of the firm, in particular, the features of the life cycles of organizations (LCO) and, finally, the theory of human capital. The involvement of these scientific approaches made it possible to demonstrate that the evolution of human capital in the correct version (during the transition from one stage of the life cycle to another) occurs synchronously with the change in the management tasks of the enterprise that arise at each stage of the life cycle of the organization. They determine the priority requests to the elements of the human capital, leading to the rotation of the latter and the selection of the most demanded among them for the corresponding stage of the life cycle. From a scientific point of view, the main result of the work was the identification of unified key stages that make up a consistent cycle of development of the human capital of an enterprise (determining its evolution), as well as the establishment of the positions of corporate and individual human capital, the most focused on solving the problems of the corresponding stage. Verification of the results obtained was carried out on the example of the evolution of the basic elements of the enterprise’s human capital — corporate culture and management style. The conclusions drawn are intended to help the management of companies to determine the components of human capital, which are mainly in demand at the corresponding stages of the life of the organization, and to choose in a timely manner the ways to increase the potential and efficiency of personnel.