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Modern engines place increasing demands on crankshaft systems, and thus bearings are required to have properties which conflict with the simultaneous need for strength and compliance under all operational conditions. Lists property requirements to describe bearing behaviour. Covers strengthening mechanisms for aluminium alloys, conformability tests, compatibility, metallurgical consequences.

The purpose of this study is to develop new Al‐based bearing alloys which have better properties than classic commercial bearing materials and to analyze tribologic properties of these alloys under dry sliding conditions experimentally.

Four different aluminium alloys were produced with casting method and tested on pin‐on‐disc wear testing machine. Friction coefficients and weight losses of the samples were determined under various working conditions in consequence of the experiments. Hardness, surface roughness, and surface temperatures of the samples were measured.

The results of the experiment show that friction coefficients vary by surface pressure and sliding speed. Al15Pb3.7Cu1.5Si1.1Fe and Al15Sn5Cu3Si alloys have lower friction coefficient values than other alloys. Al8.5Si3.5Cu alloy has the biggest wear resistance. Al15Pb3.7Cu1.5Si1.1Fe and Al15Sn5Cu3Si alloys are the most worn materials. Al8.5Si3.5Cu alloy has the lowest wear rate.

When the comparison was done between commercial Al alloys and developed Al alloys in this study, it was seen that Al15Sn5Cu3Si and Al15Pb3.7Cu1.5Si1.1Fe alloys have lower friction coefficient values than other commercial alloys.

The effects of the elements except aluminium composing alloys upon tribologic properties were analyzed. Some of the alloy elements were seen to improve tribologic properties whereas some downgrade. When the results are evaluated, Al15Sn5Cu3Si and Al8.5Si3.5Cu alloys containing Si and Sn can be preferred among the aluminium alloys that will work under dry sliding.

This paper reveals new bearing materials. These alloys can be used in journal bearings.

This paper investigates the impact of trade liberalization measured by trade openness (OPN) and tariffs on women empowerment measured by the gender gap index and gender development index, for two groups of Arab countries divided based on their income levels using annual data for the period 1995–2020. The study also considers other factors that may influence the gender gap, such as GDP growth and the female unemployment rate. The purpose of this paper is to address these issues and explorers whether the effects of trade liberalization differ based on the countries' income levels.

This study employs the fully modified ordinary least squares (FM-OLS) regression model for heterogeneous cointegrated panels to examine the impact of trade liberalization on women empowerment. The study constructs an empirical two regression model of women empowerment measured by the gender gap model and gender development model for the two groups of higher-income countries and lower and middle-income countries.

The authors’ findings reveal that the impact of OPN on the gender gap varies between the two groups of Arab countries where more OPN within the higher-income group may increase the gender disparity, while it may reduce disparity within the lower and middle-income countries. In addition, GDP growth may reduce the gender disparity, while female unemployment raises the gender disparity between the two groups of countries in the long run. Findings also reveal that more OPN, tariffs and female unemployment may reduce gender development within the two groups, but more GDP growth may support the gender development in the long run.

This paper not only assesses the impact of trade liberalization on women empowerment generally, but also assess the women empowerment via two indices that are the gender gap and gender development in Arab countries which is – to the knowledge of the researchers – not yet investigated; further it explores if the effects of trade liberalization differs based on the countries' income levels.

The purpose of this paper is to theoretically examine the effects of outward FDI on domestic aggregate productivity and welfare.

This paper develops a North-South general equilibrium model in which firms' technology adoption and workers’ skill-technology matching are endogenous. Technologically heterogeneous firms in the North make explicit delocalization decisions to the South through FDI and heterogeneous workers endogenously sort into different technologies according to their respective comparative advantages.

This paper highlights how globalization-induced technology-upgrading mechanisms of firms and workers increase aggregate productivity and welfare, though at the cost of increased income inequalities. The model shows also that the same technological shock (favoring high-tech firms) leads to different results in closed and open economy: both technology up- and downgrading occur in closed economy, while technology upgrading prevails in open economy.

By modeling and exploring the technology-skill links in a North-South setting, this paper provides richer predictions on the implications of outward FDI. In particular, the model highlights that the initial openness degree of the economy matters: the more open the country initially, the more technology upgrading as globalization proceeds, leading to higher aggregate productivity and welfare gains.

In the design of anisotropic materials, such as advanced fibre‐reinforced composites, the failure envelope has a crucial role. A geometrical representation of the envelope is of particular value to investigate the highly anisotropic nature of the strength of the material. This provides the design engineer with a visualization of the failure envelope by graphically representing it using a CAD package. Use is made of both stress‐based and strain‐based polynomial failure criteria and examples are given of changes in the failure envelope due to changes in fibre orientation for a high strength graphite/epoxy composite lamina.

The purpose of the research is to study the consequences of total (comprehensive) automatization of entrepreneurship for interested parties through the prism of competition human and artificial intellectual capital in production and distribution in Industry 4.0.

The research is conducted with application of scenario analysis, regression analysis, imitation modeling, forecasting and non-linear multi-parametric optimization with the simplex method.

The authors perform scenario modeling of competition between human and artificial intellectual capital in production and distribution in Industry 4.0 and offer recommendations for pro-active management of competition between human and artificial intellectual capital in production and distribution in Industry 4.0.

Contrary to the existing approach to studying competition between human and artificial intellectual capital in Industry 4.0, automatization of distribution, not production, is most preferable. This shows increase of the value of human intellectual capital in distribution during its automatization based on AI. This is an unprecedented and breakthrough conclusion for the modern economic science. It allows creating a completely new direction of research of competition between human and artificial intellectual capital in production and distribution in Industry 4.0, in which optimization of social consequences is achieved not by means of restraint of automatization but by means of its stimulation. The key condition is stimulation of automatization of distribution with limited automatization of production. Based on this conclusion, it is recommended to continue research in continuation of the presented work.

The purpose of this paper is to examine the link between foreign ownership and perceived job insecurity. It takes into account that the link can depend on circumstances and type of firm.

The analysis is based on linked employer-employee data from Germany. The data enable us to account for both employee characteristics and firm characteristics. Most importantly, they allow a detailed analysis of moderating influences.

The estimates show that there tends to be a positive link between foreign owners and perceived job insecurity. The link is specifically strong for foreign-owned firms with high personnel turnover or poor employment growth. It is also stronger if the foreign-owned firm providing managerial profit sharing. However, the link tends to be negative for foreign-owned firms with product innovations.

Econometric examinations on the link between foreign ownership and perceived job insecurity are scarce. The study contributes to the literature by using linked employer-employee data and provides a detailed analysis of interaction effects.

The benefits of trade liberalization on upskilling and skill-based wage premiums for high-skilled workers have recently been questioned in policy circles, in part because of rising income inequality and populist movements in developed economies such as the USA. The purpose of this paper is to determine the effects of trade liberalization on the relative supply and demand for skills.

Through the systematic review of the literature on trade and skill acquisition, this paper isolates a total of 25 articles published over the past two decades.

Key findings demonstrate the importance of the relative development of the trading partner, with more developed countries experiencing higher upskilling, while less developed countries experience deskilling. Technology, geographic level of analysis, sector and gender were also found to be important influences on human capital acquisition associated with international trade.

Overall, the authors find support for the idea that trade with developing countries places pressure on low-skill jobs in developed countries but increases the demand for educated workers. The implications of shifts in skills for public policy-making and in terms of the skill premium on wages are discussed.

In this paper we show that the neo-transitional economies are less neoliberal than could be expected given their 25-years long transition towards building market environment, supporting entrepreneurship and restoring capitalism in general. According to factor analysis results based on a cross-sectional sample of 134 countries during the period of 2010–2012 we find that the neo-transitional economies are characterised by relatively restrictive trade and capital regulations, average level of labour protection and low activity of state in terms of tax-based redistribution and social cohesion support. We briefly review several theoretical frameworks, such as the World System Theory, Commodity Chain and Global Capital theory, and Varieties of Capitalism framework, and point towards their limitations in explaining these transitional outcomes. We conclude that these frameworks are not capable of providing the explanations mainly because of their limited or no concern for labour and capital, and their interactions with the national institutions. We conclude that the history of industrialisation and path dependence provides a more plausible framework for explaining the neo-transitional outcomes. Furthermore, the consideration of the ‘resource curse’ and authoritarian regimes in many CIS countries can explain their neglect for tax-based redistribution and the high degree of government interventions in trade and capital regulations.

The purpose of this study is to assess the impact of credit constraints on agricultural labour productivity as well as the impact of credit constraints and agricultural labour productivity on rural households' consumption in Ghana.

This study uses the Ghana Living Standard Survey round six (GLSS 6) as the main source of data, which happens to be one of the most comprehensive household datasets in Ghana. Quantitative estimation techniques (namely: Endogenous Switching Regression and Two Stage Least Squares) are used to address possible endogeneity and selection into credit markets.

First, large households are prone to credit constraints while age (experience) and compliance with extension advice reduce credit constraints. Second, the determinants of agricultural labour productivity for both constrained and unconstrained households are age, sex, farm equipment, herbicide and farm size. Third, household size, education and livestock rearing influence agricultural labour productivity of constrained households. Fourth, credit constraints, irrespective of how they are measured, impede agricultural labour productivity while access to credit fosters labour productivity. Lastly, credit constraints robustly reduce consumption while agricultural labour productivity strongly enhances rural households' consumption.

The first contribution is that, unlike most previous studies, we do not focus on the widely used measure of productivity – output per unit land, but on agriculture labour productivity in particular. Secondly, unlike most previous studies which examine the effect of credit constraints either on productivity alone or consumption alone, our study examines the impact of credit constraints on both. Thirdly, unlike the existing literature which uses one or two measures of credit constraints, we use a wide range of measures of credit constraints – seven different measures of credit constraints. Lastly, our empirical strategy solves at least two critical econometric problems – sample selection bias and endogeneity.