One-axis stretching of the elasto-plastic plates with square hole of different orientation relatively the axis of stretching

На основі числового розв’язування крайових задач теорії малих пружно-пластичних деформацій для лінійно зміцнюваного матеріалу з урахуванням розвантаження з’ясовано вплив орієнтації квадратного отвору в пластині на її напружено-деформований стан за одновісного розтягу.Effective numerical methods for solving 2D problems related to the theories of elasticity and plasticity have been worked out. The variation-difference method of building finite difference schemes is extended to domains with curvilinear boundaries and disconnected domains. The application of the variation-difference method for solving problems of the theory of small elasto- plastic deformations relatively the plates with a hole, taking into account the linear strengthening of the material and unloading, has been developed. For solving the resultant systems of nonlinear and linear equation, the Newton-Kantorovich method and combined iterative method (gradient and cyclic Chebyshev’s one) were proposed to be used. The choice of iteration parameters of the methods for solving the obtained systems of linear and nonlinear algebraic equations was made. The elaborated software ensures solving the problems with different boundary conditions, medium and domain parameters. A variety of problems concerning one-axis stretching of the plates with the square hole of different orientation relatively the axis of stretching is numerically solved. The zones of evolution of plastic deformations for step enlarging of the loading are constructed, the remaining deformations and the limit loads are obtained. The influence of the orientation of square hole in the plate onto the stress magnitude was found. The orientation of the hole does not make essential influence onto the shape of zones of generation and development of residual deformations, but it essentially impacts onto magnitudes of the components of the stress tensor and its intensity, and therefore the moment of the beginning of plastic deformation. That is, in a plate with rotated square hole the initial plastic deformations appear under the tension 45% less than in a non-rotated one

Labour in fisheries: Task analysis of fishing operations on a Norwegian trawler

This study investigates the labour on a Norwegian trawler through the study of tasks that are performed under the trawling operation. Study of tasks is one of the fundamental approaches to studying labour, and in this thesis, it is carried out using the technique of Hierarchical Task Analysis. This task analysis technique has been broadly and universally used in different industries for over 60 years. Hierarchical Task Analysis represents the system of labour tasks and goals that are achieved by performing the tasks, creating an objective picture of labour on a fishing vessel, and visually represents them as a hierarchical system of plans of tasks. After identifying and describing the tasks, each of these tasks is investigated further in terms of talk allocation, character of performance, and number of performers required to complete a task. Hierarchal task analysis contributes significantly to the system description, system investigation and system design. It discovers the tasks and human-machinery interventions, risks for operators’ mistakes. This approach is seen as translational and fundamental for disciplines that concern labour in direct or indirect way, therefore the findings of the study are discussed from the perspective of complementing present labour research and further utilization in safety studies, autonomation and other topics

Hydraulic working standard of gas volume

Акцентовано, що розмір одиниці об’єму та об’ємної витрати газу доцільно було б отримувати від Державного первинного еталона одиниць об’ємної та масової витрати рідини та газу й об’єму та маси рідини та газу, еталонів передавання, вторинного еталона чи робочих еталонів. Для реалізації можливості передавання розміру одиниці об’єму газу лічильникам та витратомірам газу від еталонів з Державної повірочної схеми для засобів вимірювання об’ємної та масової витрати рідини й об’єму та маси рідини, що протікає по трубопроводу, запропоновано внести зміни в конструкцію робочого еталона на базі мірника об’єму газу з рідинним розділювачем шляхом додаткового обладнання набором еталонних витратомірів рідини, що дозволить прямим методом вимірювати об’єм рідини, яка переливається із компенсуючої в мірну ємність, чим забезпечується більша точність вимірювання об’єму розділювальної рідини у порівнянні з відомими аналогами. Використання розробленого робочого еталона дасть змогу здійснювати передавання розміру одиниці об’єму та об’ємної витрати в рамках одного виду вимірювань – від еталонних витратомірів рідини до лічильників та витратомірів газу.The transmission of gas volume and volume flow unit to gas meters and flow meters is implemented from State primary standard of volume and volume flow units of gas with the help of transmission standards, secondary or working standards. Measurement of gas volume and volume flow is a type of measurement of volume and mass flow of liquid and gas, volume and mass of liquid and gas. That’s why volume and volume flow unit of gas should be provided by State primary standard of volume and mass flow units of liquid and gas, volume and mass of liquid and gas, transmission standards, a secondary standard or working standards. To realize the possibility of transmission of gas volume unit to gas meters and flow meters from standards of State calibration scheme for measurement of volume and mass flow of liquids, volume and mass of liquids flowing through the pipeline it is proposed to insert changes into the construction of working standard on the basis of a measuring instrument of gas volume with a liquid separator by additional installment of a set of standard flow meters of liquid that will enable to measure the volume of liquid pouring from a compensating into measuring capacity by a direct method. It ensures a greater exactness in the process of measurement the volume of separate liquid in comparison with known analogues when the given physical quantity is measured by indirect methods (level of liquid, geometric parameters of gas measuring instrument), which are always less exact because of great number of component errors in measurements. Moreover, a set of standard flow meters of liquid will provide widening of measuring flow range of separate liquid and, consequently, flow range of gas by which gas meters will be calibrated. In hydraulic working standard of gas volume the 1-st type standard flow meters of liquid included into calibration scheme for measurement of volume and mass flow of liquid, volume and mass of liquid are used. Using the developed working standard will enable the implementation of volume and volume flow unit transmission within one type of measurement ─ from standard flow meters of liquid to meters and flow meters of gas. The development of metrological support of the proposed working standard and its metrological model will be the subject of further researches

Influence of stress concentrators onto stress-strain state of elasto-plastic plates

На основі числового розв’язування крайових задач теорії малих пружно-пластичних деформацій для лінійно зміцнюваного матеріалу з урахуванням розвантаження з’ясовано вплив концентраторів напружень (отвору, розрізу, абсолютно жорсткого включення) в пластині на її напружено-деформований стан за одновісного розтягу.Effective numerical methods for solving 2D problems related to the theories of elasticity and plasticity have been worked out. The variation-difference method of building finite difference schemes is extended to domains with curvilinear boundaries and disconnected domains. The application of the variation-difference method for solving problems of the theory of small elasto-plastic deformations relatively the plates with a hole and a cut, taking into account the linear strengthening of the material and unloading, has been developed. For solving the resultant systems of nonlinear and linear equation, the Newton-Kantorovich method and combined iterative method (gradient and cyclic Chebyshev’s one) were proposed to be used. The choice of iteration parameters of the methods for solving the obtained systems of linear and nonlinear algebraic equations was made. The elaborated software ensures solving the problems with different boundary conditions, medium and domain parameters. A variety of problems concerning one-axis stretching of the plates with a disk hole (or rigid body instead of a hole) and a cut (or a thin rigid body instead of a cut) is numerically solved. The zones of evolution of plastic deformations for step enlarging of the loading are constructed, the residual strains and the limit loads are obtained. The influence of a disk hole, cut and rigid body instead of a hole or cut in the plates onto the stress magnitude was found. The presence of rigid bodies instead of a hole or a cut strengthen the plate in general, in particular, plastic strains in the plate with rigid bodies instead of a hole and a cut appear under tension stress in 2,75 times more, than in the plate with a disk hole and a cut, and yield limit arrives at tension stress in 1,79 times more. A long thin rigid body strengthens a plate more than a disk one. The residual strains around a rigid body in the plates with a disk rigid body and a cut, and in the plates with a disk hole and a thin rigid body do not arise, in general

Stress-strain state of elasto-plastic linearly strengthenable plates with two perpendicular cuts under all-round stretching

За допомогою числового розв’язування крайових задач теорії малих пружно-пластичних деформацій для лінійно зміцнюваного матеріалу з’ясовано напружено-деформований стан пружно-пластичних пластин з двома перпендикулярними розрізами за всебічного розтягу.Effective numerical methods for solving 2D problems related to the theories of elasticity and plasticity have been worked out. The variation-difference method of building finite difference schemes is extended to disconnected domains. The application of the variation-difference method for solving problems of the theory of small elasto-plastic deformations relatively the plates with cuts, taking into account the linear strengthening of the material and unloading, has been developed. For solving the resultant systems of nonlinear and linear equation, the Newton-Kantorovich method and combined iterative method (gradient and cyclic Chebyshev’s one) were proposed to be used. The choice of iteration parameters of the methods for solving the obtained systems of linear and nonlinear algebraic equations was made. The elaborated software ensures solving the problems with different boundary conditions, medium and domain parameters. A variety of problems concerning all-round stretching of the elasto-plastic plates with two perpendicular cuts is numerically solved. The zones of evolution of plastic deformations for step enlarging of the loading are constructed. There are found the stresses under which the yield limit and the strength limit are achieve in the plates. On the base of numerical analysis the following main regularities are found: under the close mutual location of cuts in the plate, the plastic deformations first appear under the stress which is 33% less than in the plate with the same cuts under the far mutual location; however, the strength limit in the plates in the both considered cases is achieve practically under the same stress

Alexis de Tocqueville’s Political Science of Revolutions; Theory and Application

This dissertation examines the theory of revolutions presented in the main writing of Alexis de Tocqueville and its importance in the field of political theory as well as its possible application in the field of comparative politics. Scholars specializing in the study of the writings of Alexis de Tocqueville have for many years debated on whether the works of this author offer a comprehensive political theory of regimes and political change. This work supports the idea that in all his major writings de Tocqueville works within the same theoretical framework and develops his own typology of modern regimes. At the same time the work argues that de Tocqueville focuses not on “democracy” as such, but on the notion of revolution in modern politics. The resulting general model proposed by the dissertation combines elements of the ancient cyclical science of regimes with the modern concepts of political progress. The dissertation argues that this theoretical scheme is endowed with immense predictive power. It exemplifies the use of Tocqueville’s political science of revolutions with both historical and contemporary examples. The two final chapters contain a possible expansion of the Tocquevillian theoretical framework to account for the political phenomena that are still in their nascent stages of development

The Impact of Globalization on European Airline Market

Airline industry is very important for modern society as the biggest player in the globalization process by connecting regions, promoting global trade and tourism, facilitating economic and social development. However, here is a lack of research on relationship between globalization and airline industry in Europe. It remains unclear how to measure the impact of globalization on performance of airline companies and industry. The article aims at investigation of the impact of globalization on operational and financial performance of European airlines before pandemics.The authors applied a nonexperimental quantitative research design to analyze the relationship between independent globalization variables (level of globalization in Europe, globalization opportunity, globalization threat) and dependent airlines’ operational and financial performance indicators. Research is done using secondary data from annual reports of 19 European airlines members of European Common Aviation Area (ECAA). The panel data analysis was applied for 2007–2017 with multiple regression analysis using STATA. The results show that globalization exerts a significant positive effect on operational performance. On financial performance only revenue per passenger kilometers is positively influenced by globalization. Globalization affects low-cost airlines and full-service airlines performance differently