Features Of Structural Transformations Research Articles

Vertical integration, technical progress and structural change

Abstract In search of an alternative representation of the economic system, Pasinetti ended up with a notion of vertical integration (VI) that takes interdependencies as its starting point but does not explicitly consider their role in the unfolding structural economic dynamics (SED). In this paper, we show that SED may be more inclusive of such interrelations to appropriately consider VI as a tool for analysing economic systems under the conditions of technical change and structural transformation. Our strategy is to focus on Pasinetti’s shift from his original development building on Sraffa’s sub-systems to his formulation of VI in terms of a pure labour technology in which all goods are produced by labour only. To carry out the analysis, we resume his iterative algorithm of VI, showing that we can extend it to the case of an expanding economy as a bridge between the horizontal and vertical production representations. Following this route, we can effectively address the features of structural transformation associated with changing patterns of interdependence. Besides, we can go from an assessment of productivity growth at an industrial level to determining the pace of technical change in a vertically integrated sector (VIS), which allows focussing on a concept of productivity derived from the VI, labelled as the total labour productivity (TLP). The TLP is robust to outsourcing of production, whose effects are adequately dealt with insofar as it considers not only the direct but also the indirect labour required to produce the final output.

Структурно-динамічний аналіз ІТ-ринку України: виклики сьогодення

The aim of the article is to study the trends and features of structural transformations of the IT market of Ukraine over the past decade. Taking into account the consideration that there is still no single statistical base and system of indicators that would fully reflect the state of functioning of the IT market in Ukraine, as is revealed by the analyses of many information sources, the main structural transformations of the IT market of Ukraine as of 2013, 2018 and 2023 were analyzed and researched. As result of the carried out study, it is found out what structural changes took place during these periods in the IT labor market, in the market of IT products, in the economics of the IT business in general, etc. This made it possible to better assess the potential of the national IT market, identify potential threats to its development, competitive environment, and form a systematic view of the state and prospects for the development of the IT sector of the national economy, also to outline the key trends that will determine the development of the IT market in the near future. The factors of national and global scale, under the influence of which the IT market of Ukraine will be formed and function in the future, have been identified. In particular, it is the continuation of hostilities on the territory of Ukraine; irregularity of the process of reservation of critical employees of the IT industry and sending them on business trips abroad; lack of free money in the economy; global recession due to the energy crisis; companies’ attraction to optimize costs for the development along with further development of artificial intelligence. It is found that in 2023, for the first time in a decade, there is a downward trend in the volume of the IT market. This is testified by the departure of IT specialists abroad, a drop in the export of IT services, significant layoffs of IT specialists by companies, a long-term delay in the revision of salaries, a freeze in the increase in the level of compensation and bonus payments, a change in the situation in the talent market not in favor of Ukrainian IT specialists, etc. Prospects for further research in this direction are the substantiation of making appropriate managerial decisions to curb the decline of the IT market and the introduction of additional tools to stimulate its development in the dynamic economic conditions that have developed both within the country and around the world.

ОЦЕНКА ЭФФЕКТИВНОСТИ ИСПОЛЬЗОВАНИЯ РЕГИОНАРНОЙ ЛИМФОТРОПНОЙ ТЕРАПИИ ПРИ ЭКССУДАТИВНОМ СРЕДНЕМ ОТИТЕ В ЭКСПЕРИМЕНТЕ

In lymphology, there is a great potential of knowledge about the role of the lymphatic system in the implementation of water homeostasis, as one of the most important factors of the constancy of the internal environment of the body, drainage, and detoxification of tissue fluid and lymph. The lymphatic system is one of the first to react to the inflammatory process in any region of the human body; therefore, an obligatory element of the standard of examination of patients is to assess the condition of regional lymph nodes. At the same time, the lack of data on the involvement of the lymphatic system in the development of exudative otitis media hinders the development of new pathogenetically sound modern methods of lymphotropic therapy of one of the diseases common in otorhinolaryngology. In this work, the features of structural transformations of different groups of neck lymph nodes (superficial, facial, deep) belonging to the lymphatic region of the middle ear are studied and shown under physiological conditions, when modeling exudative otitis media and after lymphotropic therapy involving the introduction of a mixture of drugs into tissues using low-frequency ultrasound. According to the degree and nature of the response of the structural components of the nodes to the modeling process in the experiment of exudative inflammation in the middle ear and therapeutic measures aimed at lymphosanation, nodes of the first order – deep lymph nodes, and of the second order – superficial lymph nodes were identified. Therapy aimed at the rehabilitation of the lymphatic region of the middle ear and associated cavities leads to complete normalization of the lymph nodes and relief of inflammatory processes, therefore it can be considered pathogenetically justified.

Comparative Investigation of the Influence of Ultrafine-Grained State on Deformation and Temperature Behavior and Microstructure Formed during Quasi-Static Tension of Pure Titanium and Ti-45Nb Alloy by Means of Infrared Thermography.

A comprehensive study was performed of the deformation and temperature behavior during quasi-static tension, as well as the peculiarities of accumulation and dissipation of energy during plastic deformation. Microstructural analysis at the pre-fracture stage of pure titanium and Ti-45Nb alloy in the coarse grain (CG) and ultrafine-grained (UFG) states was also conducted. It was shown that substructural and dispersion hardening leads to a change in the regularities of dissipation and accumulation energies during deformation of the samples of the pure titanium and Ti-45Nb alloy in the UFG state. Some features of structural transformations during deformation of the pure titanium and Ti-45Nb alloy samples in the CG and UFG states were studied. A band and cellular-network and fragmented dislocation structure was formed in the case of the CG state, while large anisotropic fragments were formed in the UFG state, thus specifying a local softening of the material before fracture.

Structural transformations during annealing of cold-worked high-entropy alloy Al0.3CoCrFeNi

The paper considers the features of structural transformations during annealing of the high-entropy alloy Al0.3CoCrFeNi. The ingots obtained by argon arc melting were subjected to cold rolling with a compression ratio of 50 %. The produced worpieces were annealed in the furnace for 4 hours at temperatures of 200, 400, 600, 800 and 1000 °C. The samples obtained by the described technique were examined using the methods of synchrotron X-ray diffraction in the lumen mode and diffraction of backscattered electrons. The research data indicate that up to a temperature of 600 °C, the structure of the alloys is represented by a single phase with a face-centered cubic lattice. When annealing alloys at temperatures of 800 and 1000 °C, the phase composition is characterized by the presence of two phases: a disordered phase with a face-centered cubic lattice and an ordered phase with a primitive cubic lattice. At temperatures above 800 °C, the burning of alloys is accompanied by development of recrystallization processes. It was found that after annealing at 800 °C, the relative proportion of micro-volumes characterized by inter-angular misorientation of more than 10° was 20 %, and after annealing at 1000 °C – 65 %. Microhardness of the studied samples increases with an increase in temperature up to 600 °C and decreases with a further increase in temperature. Analysis of the width of diffraction maxima using the methods of profile analysis of diffractograms indicates an increase in distortions of the crystal lattice of the ordered phase. This behavior may be associated with the release of nanoscale inclusions in the matrix of the main phase.

Barrier-free molecular reorientations in polyhedral water clusters

The structural stability of the weakest bonded configurations of water clusters in the form of gas hydrate cavities D and T, as well as in the form of Kelvin’s polyhedron, was tested using the local geometric optimization with the polarizable force field AMOEBA. A number of different barrier-free molecular rearrangements were observed. Most of the configurations changed their shapes, forming surface defects of the same type. But the main attention is paid to the concerted molecular reorientations leading to the proton shift along hydrogen bonds. A number of statements about the topology of the hydrogen-bonded network are rigorously proved. It is concluded that the structural stability of configurations and the features of structural transformations are basically determined by the arrangement of the homodromic hydrogen-bonded water rings. The stability of the configurations, which retained their original shape during local geometric optimization, was studied by the molecular dynamics method with a gradual increase in temperature. Some interesting effects were found. This is the stabilizing locking of the most polarized configurations, as well as very intense amplitude oscillations of the free OH group at the end of two-bond flips.

Features of Structural Transformations and Properties of Polycaproamide Modified with Polyfluorated Alcohol Immobilized on Montmorillonite

The effect of 1,1,9-trihydroperfluorononanol-1 immobilized on montmorillonite nanoclay on the nature of structural transformations and the properties of polycaproamide composites was studied. Using the methods of electron, atomic force microscopy and differential scanning calorimetry, we established the features of changing the diameter and height of spherulites in non-oriented films of this heterochain polymer, as well as the reorganization of its polymorphic composition due to the introduction of a fluorine-containing modifier. The stabilizing effect of the additive used on the mechanical properties and thermo-oxidative stability is shown.

Stress-strain state and structure of pure copper and Grade 4 titanium after free bending

This paper investigates the stress-strain state and the features of structural transformation in materials with different types of crystalline lattices in the process of deformation by free bending of axis-symmetrical billets. As the materials for the study, we selected oxygen-free M00B Cu and Grade 4 CP Ti. Using mathematical modeling, we study the stress-strain state of the samples from the selected materials in the process of bending via different routes. We study the structure in the mesoscale and determine the features of structural transformation. It is found that in the process of bending of Cu, a refined surface layer with a thickness of 20-30 μm and a cell size of ≈1 μm forms already after 1 processing cycle. In the process of bending of Ti, twinning occurs in peripheral regions, and the efficiency of twinning via route C is higher than that via route A. The most efficient, in terms of strengthening, processing routes of bending are determined.

Specific Features of Structure Transformation and Properties of Amorphous-Nanocrystalline Alloys

This work is devoted to a brief overview of the structure and properties of amorphous-nanocrystalline metallic alloys. It presents the current state of studies of the structure evolution of amorphous alloys and the formation of nanoglasses and nanocrystals in metallic glasses. Structural changes occurring during heating and deformation are considered. The transformation of a homogeneous amorphous phase into a heterogeneous phase, the dependence of the scale of inhomogeneities on the component composition, and the conditions of external influences are considered. The crystallization processes of the amorphous phase, such as the homogeneous and heterogeneous nucleation of crystals, are considered. Particular attention is paid to a volume mismatch compensation on the crystallization processes. The effect of changes in the amorphous structure on the forming crystalline structure is shown. The mechanical properties in the structure in and around shear bands are discussed. The possibility of controlling the structure of fully or partially crystallized samples is analyzed for creating new materials with the required physical properties.

Deformation-induced martensite transformation in AISI 321 stainless steel under dry sliding friction

Austenitic stainless steels are some of the most popular structural materials. This is explained by their chemical and mechanical properties among which one may particularly note their high ductility. Due this reason they are successfully subjected to cold working. One of the interesting phenomena of mechanical impact on the structure of austenitic stainless steels is a strain-induced martensitic transformation. The formation of martensite (α'-phase) is due to the metastable state of austenite (γ-phase) near the room temperatures. Such structural transformation can lead to both positive and negative effects. For instance, the increase in the fraction of α' leads to decrease in corrosion resistance. Therefore, consideration of the mechanism of deformation-induced transformation requires additional attention. In this paper, the first results of the analysis of AISI 321 stainless steel subjected to friction are presented. Operando studies using synchrotron radiation were carried out to identify the features of structural transformations. It was established that friction interaction leads to complete γ → α′ transformation. Strain hardening and fracture of subsurface layers were revealed with metallographic analysis. It was evaluated that a hardness of strain-induced phase more than twice higher than the hardness of austenite.

Особенности структурной трансформации дисперсно-упрочненных ванадиевых сплавов в условиях деформации кручением под давлением и растяжения при комнатной температуре

Особенности структурной трансформации дисперсно-упрочненных ванадиевых сплавов в условиях деформации кручением под давлением и растяжения при комнатной температуре

Особенности структурных преобразований таможенных органов на современном этапе

Особенности структурных преобразований таможенных органов на современном этапе

Structural Transformations in the Grain Boundary Region of Nanocrystalline Metals Under Mechanical Loading

Molecular dynamics analysis of special features of structural transformations at the grain boundaries (GBs) of nanocrystalline metals with face-centered cubic (FCC) and body-centered cubic (BCC) lattices under shear loads is performed. The objects of the study are nickel and vanadium samples containing symmetric tilt GBs. Shear loading is specified by the displacement of the surface atomic layers parallel to the GB plane at a constant speed. Shear load causes a high-speed GB movement along the normal to the boundary plane. To initiate the GB movement, high stress is required. Periodic boundary conditions prevent the occurrence of the grain rotations. The GB velocity is determined by the shear rate and depends on the grain misorientation angle. It has been found that the GB movement has a jump-like nature and is accompanied by a rapid drop in the internal stresses. Self-consistent structural transformations of atomic planes, through which the high-speed GB movement in a metal occurs, are revealed.

Investigation of the structural-phase state under superplastic deformation of the Co-Ni-Nb alloy

ABSTRACTThe formation of the Co-Ni-Nb alloy structure under superplastic deformation and phase composition is studied in the article. Investigations of the changes in the true stresses during superplastic deformation in the optimal mode of the dispersion-hardening alloy on a cobalt–nickel-niobium basis are carried out. The structure change at various degrees of deformation is studied. The features of structural transformations under superplastic deformation are analyzed. The evolution of the secondary phase and the change in the chemical and phase composition are considered as a result of the motion of the shear transformation zone.

Structural change and economic growth in India

Using detailed sectoral data from India KLEMS, we analyze the role of structural change in determining India's aggregate productivity growth during 1980–2011. In general, the impact of static structural change on aggregate labor productivity growth has been positive, as workers moved to sectors of a relatively higher labor productivity level. However, dynamic reallocation effects—worker movement to fast-growing industries—have not been observed. The pro-market reforms in the 1990s did help a TFP growth-enhancing allocation of capital across sectors. The relative importance of the manufacturing sector for aggregate TFP growth has increased in recent years. Yet, India's structural transformation features the absorption of workers in the construction sector and slow and stagnant job creation respectively in services and manufacturing sectors. This poses a challenge, as the potential for productivity growth in construction and services are limited, and the changing nature of manufacturing production provides less room for absorbing less-skilled workers.

Effect of Continuous Extrusion Parameters on Alloy M1 Round Section Bar Microstructure and Mechanical Property Formation

Results are provided for microstructural evolution and mechanical property formation in a deformation zone during continuous extrusion, and the effect of extrusion rate parameters on the properties of M1 grade copper rods is also evaluated. The study is conducted on butt-ends and bars obtained in a Conform 350 industrial unit. Investigation of metal flow in the deformation zone shows that features of structure transformation are retained for all specimens. A cast (undeformed) billet has a structure with a large grain size (80–1000 μm). As a result of extrusion a workpiece structure grain size is reduced to 50–35 μm. Quantitative data are obtained for the formation of finished product hardness in relation to equipment configuration and extrusion parameters. Samples extruded at a rate of 6 m/min have an optimum hardness level (62.5 kgf/mm2) that satisfies the standard specifications, unlike other samples extruded at a slower rate.

UNIVERSITY EDUCATION IN THE FRENCH REPUBLIC: STRUCTURE AND LEGAL FRAMEWORK

The article deals with the complex and multistage system of higher education of the French Republic. The structural features of higher education in France, its complex and multi-stage system has been considered. Attention is drawn to the role of the state in the field of higher education in France. The importance of the development of education for the national development of the country and civilization as a whole has been stressed. A strong centralized presence and role of the state in the field of education in France has been noted, in particular in the organization of the educational process and in financing the education sector, as well as in determining the fundamental principles of the educational process, the details of the curriculum at all levels of education, the organization of the procedure for receiving teachers, determining the content, recruitment teachers who become public officers, ensuring their continuing education; recruiting and training inspectors responsible for quality control of the education system; funding public education and subsidizing “private schools under contract”. The article focuses on the constant attention of the state to the problems of education. It highlights the openness of the French system of higher education and its accessibility for most of the population. The features of France’s higher education management system and the specifics of its legislative framework have been disclosed. Four Legislative Acts of the Ministry of Education are characterized, played an important role in its functioning. A more democratic and collegial management of universities for today has been noted. The relevance of the study of the structure and legislative framework of university education in France has been grounded. The types of higher education institutions in France and their features in the context of development trends have been investigated. The current stage of development of the system of French university education and the features of structural transformations have been considered. The features of the functioning of universities, “grand schools” and private higher education institutions have been disclosed. The article draws attention to the achievement of the French system of higher education and its uniqueness. The role and place of large schools in the system of higher education in France have been highlighted. Leading elite schools and universities have been mentioned, as well as the conditions for entering them. Attention was paid to the almost equal quality of education in the capital and in the province.

Economy of a large city: structural transformations in the era of global changes

The paper outlines the features of structural transformations in the economy of large cities in conditions of globalization. Special attention is paid to finding priority directions and mechanisms of impact of global economic changes on evolutionary advances in economic structure of large cities. The decisive role of large cities in economic development of contemporary states is emphasized. The processes are accompanied by constant growth of the share of urban population and concentration of growing economic capacity in cities. Moreover, more and more metropolises and global cities emerge. Their major advantage is a high concentration level of production capacities and capital as well as significant human capacity, which promotes innovative development of various sectors of urban economy, mostly energy, information technologies, transport, household services, leisure and banking sector, etc. The following problems are defined as the most essential of those faced by large cities in the era of globalization: deteriorating quality of social capital, growing security challenges, growing risks of technological disasters, deteriorating quality of environment and environmental situation in general, growing load on engineering and social infrastructure, need to secure constant supply of sufficient volumes of drinking water and food. The paper proves that the priority directions of economy development in large cities in the era of globalization is to improve the mobility of population, improve living conditions and meet high standards of citizens’ household comfort, form innovative information-communication networks, establish qualitative planning of urban space, solve ecological problems, namely through renewable energy and prioritization of environmental protection. Recommendations regarding top priority measures of adaptation of large Ukrainian cities to modern requirements of globalization based on the experience of the most developed countries in the world are suggested. In particular, the authors emphasize the need to increase the volumes of investment in the development of information technologies and activation of digitalization of urban space due to releasing the share of budget resources currently inefficiently used and directing them on meeting social needs of citizens.

Structural Transformations Occurring upon Explosive Welding of Alloy Steel and High-Strength Titanium

Features of the structure of a layered material welded by explosion of high-strength titanium alloy and tool roller steel with an intermediate layer of the structural low-carbon steel have been studied. The structural transformations occurring in materials upon their dynamic interaction have been analyzed. Particular attention is paid to the structure of vortex zones formed at the interfaces of billets of various steels, as well as structural steel and titanium-based alloy. The structural analysis methods made it possible to fix stable and metastable joints appearing upon the explosive welding of various metals. To reveal features of structural transformations caused by prolonged heating, billets of titanium alloy and structural steel were also joined by diffusion welding. It has been shown that, in the course of the diffusion welding process, a continuous layer of stable brittle intermetallic compounds is formed along the entire interface of the welded materials. In the explosively welded materials, the intermetallic phases are distributed locally and, thus, they have a weaker embrittlement effect.

РОЗВИТОК УНІВЕРСИТЕТСЬКОЇ ОСВІТИ ФРАНЦІЇ: ІСТОРИЧНИЙ АСПЕКТ

The relevance of the study of the historical development of university education in France has been grounded in the article. The complex and multistage system of French higher education has been considered. The stages of the development of education in French universities have been determined and the features of each of these stages have been considered. The article highlights the formation and historical development of higher education in France. The article draws attention to the achievements of the French system of higher education and its uniqueness. The role and place of grand schools in the system of higher education in France have been singled out. The leading grand schools and universities have been mentioned in the article, and the conditions of admission to them have been stated. The attention has been paid to practically equal quality of education in the capital and in the province. The unique features of France’s higher education, conditioned by the stages of its historical development and social processes, have been determined. In the article the attention has been drawn to the national character of the French higher education. The role of the state in financing of the higher education in France has been considered. France’s participation in students’ mobility programs has been stated. The modern stage of development of the system of French university education, the features of structural transformations and the possibility of implementing of French experience in Ukraine have been considered.