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This study aims to investigate the influence of geometry of bush-pin pair from a perspective of optimal lubrication through a thermal elastohydrodynamic lubrication model for finite line contact.

A constitutive equation: Ree-Eyring fluid is used in the calculations. The real chain sizes, i.e. equivalent radius of curvature, bush length, length of the rounded corner area and rounded corner radius, are jointed investigated. Moreover, the effects of the length of the rounded corner area and the radius of rounded corner are investigated.

It is found that the current standard of the chain might not consider the importance of lubrication, and the lubrication state can be improved effectively by choosing an optimal radius of rounded corner and the length of the corner area.

By optimally selecting sizes, the occurrence of high pressure, high temperature rise and near zero film thickness at the ends of bush, especially under heavier load, can be effectively avoided.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-01-2020-0031/

The purpose of this paper is to study the influence of surface precision on the lubrication state of the roller chain under adequate and rare oil supply conditions, respectively.

The straightness error and roughness error of the pin generatrices were measured and the influence of surface precision on the lubrication behavior under steady state and reciprocating motion was studied through optical interference experiments.

The lubrication state is strongly influenced by the surface precision of the roller surface both under adequate oil supply and rare oil supply conditions.

In industrial applications, the machining errors of parts cannot be completely eliminated. Studying the influence of the surface precision on the lubrication behavior of pin–bush pairs can provide the experimental basis for the optimal design of the bush roller chains.

The purpose of this paper is to fill important gaps by using the attachment theory and examining the effects of supervisors’ early family environment on their behaviors toward subordinates and subordinates’ responses.

The authors used samples of 334 supervisor–subordinate pairs from a manufacturing company.

The study finds that supervisors’ harmonious family environment has a positive influence on subordinates’ responses (job satisfaction, work-to-family enrichment and task performance) through the effect of supervisors’ positive working model and caregiving behavior. On the contrast, supervisors’ conflicting family environment has a negative influence on subordinates’ responses through the effect of supervisors’ negative working model and aggressive behavior.

Existing studies mainly explore the influence of organizational environment on supervisors’ treatment of their subordinates. However, few have examined the relationship between supervisors’ early family environment and their treatment of their subordinates.

The purpose of this paper is to numerically study the variations of oil film pressure, thickness and temperature rise in the contact zone of plate-pin pair in silent chains.

A steady-state thermal elastohydrodynamic lubrication (EHL) model is built using a Ree–Eyring fluid. The contact between the plate and the pin is simplified as a narrow finite line contact, and the lubrication state is examined by varying the geometry and the plate speed.

With increase in the equivalent radius of curvature, the pressure peak and the central film thickness increase. Because the plate is very thin, the temperature rise can be neglected. Even when the influence of the rounded corner region is less, a proper design can beneficially increase the minimum film thickness at both edges of the plate. Under a low entraining speed, strong stress concentration results in close-zero film thickness at both edges of the plate.

This study reveals the EHL feature of the narrow finite line contact in plate-pin pairs for silent chains and will support the future works considering transient effect, surface features and wear.

This paper aims to study the influence of the dimension change of bush-pin on the pressure, oil film thickness, temperature rise and traction coefficient in contact zone by using a thermal elastohydrodynamic lubrication (EHL) model for finite line contact. Concretely, the effects of the equivalent curvature radius of the bush and the pin, and the length of the bush are investigated.

In this paper, the contact between the bush and pin is simplified as finite line contact. The lubrication state is studied by numerical simulation using steady-state line contact thermal EHL. A constitutive equation Ree–Eyring fluid is used in the calculations.

It is found that by selecting an optimal equivalent radius of curvature and prolonging the bush length can improve the lubrication state effectively.

Under specific working conditions, there exists an optimal equivalent radius to maximize the minimum oil film thickness in the contact zone. The increase of generatrix length will weaken the stress concentration effect in the rounded corner area at both ends of the bush, which can improve the wear resistance of chain.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-10-2019-0448.

The purpose of this paper is to use elastohydrodynamic lubrication (EHL) theory to study the variation of the equivalent curvature radius “R” on the change of oil film thickness, pressure, temperature rise and friction coefficient in the contact zone between bush-pin in industrial chain drive.

In this paper, the contact between bush and pin is simplified as infinitely long line contact. The lubrication state is studied by numerical simulation using steady-state line contact thermal EHL. The two constitutive equations, namely, Newton fluid and Ree–Eyring fluid are used in the calculations.

It is found that with the increase of equivalent curvature radius, the thickness of oil film decreases and the temperature rise increases. Under the same condition, the friction coefficient of Newton fluid is higher than that of Ree–Eyring fluid. When the load increases, the oil film thickness decreases, the temperature rise increases and the friction coefficient decreases; and the film thickness increases with the increase of the entraining speed under the condition “R < 1,000 mm”.

The infinite line contact assumption is only an approximation. For example, the distances between the two inner plates are 5.72 mm, by considering the two parts assembled into the inner plates, the total length of the bush is less than 6 mm. The diameter of the pin and the bore diameter of the bush are 3.28 and 3.33 mm. However, the infinite line contact is also helpful in understanding the general variation of oil film characteristics and provides a reference for the future study of finite line contact of chain problems.

The change of the equivalent radius R on the variation of the oil film in the contact of the bush and the pin in industrial chain drive was investigated. The size effect influences the lubrication characteristic greatly in the bush-pin pair.

This study aims to provide a series of drivers that prompt the blockchain technology (BT) adoption decisions in circular supply chain finance (SCF) and also assesses their degrees of influence and interrelationships, which leads to the construction of a theoretical model depicting the influence mechanism of BT adoption decisions in circular SCF.

This study mainly uses the technology-organization-environment (TOE) framework, which focuses on the aspects based on the nature of innovation, intra-organizational characteristics and extra environmental consideration, to identify the drivers of blockchain adoption in circular SCF context, while the significance and causality of the drivers are explained using interpreting structural models (ISMs) and the decision-making trial and evaluation laboratory (DEMATEL) method.

The findings of this study indicate that government policy and technological comparative advantage are the underlying reasons for BT adoption decisions, management commitment and financial expectations are the critical drivers of BT adoption decisions while other factors are the receivers of the mechanism.

This study provides theoretical references and empirical insights that influence the technology adoption decisions of both BT and circular SCF by practitioners.

The theoretical research contributes significantly to current research and knowledge in both BT and circular SCF fields, especially by extending the existing TOE model by combining relevant enablers from technological, organizational and external environmental aspects with the financial performance objectives of circular SCF services, which refer to the optimization of the financial resources flows and financing efficiency.

The purpose of this paper is to study the interaction of main marine organisms on localized corrosion of 316L stainless steel in the Dalian Sea area.

The steel plate was immersed in the Dalian Sea area for nine months to observe the biofouling and localized corrosion. The local potential distribution on the steel plate covered by marine organisms was measured. The local electrochemical measurements were performed to facilitate understanding the interfacial status under different biofouling conditions. The local surface morphologies and corrosion products were characterized.

The localized corrosion of stainless steel is mainly induced by the attachment of barnacles on the steel. The mussels have no influence on the localized corrosion. The cover of sea squirts could mitigate the localized corrosion induced by barnacles. Both crevice corrosion and pitting corrosion were found beneath the barnacle without the covering of sea squirts. The pitting damage was more serious than the crevice corrosion in the Dalian Sea area. The probing of sulfur element indicates that the potential growth of sulfate-reducing bacteria at barnacle center.

The above findings revealed that the interaction of marine organisms has significant influences on the localized corrosion of stainless steel. The influences of macro-fouling and micro-fouling on localized corrosion are discussed.

Considering the role of analysts in disseminating information, the paper explains the idiosyncratic volatility puzzle of China's stock market. As the largest developing country, China's research can provide meaningful reference for the research of financial markets in other new countries.

From the perspective of behavior, establishing a direct link between individual investor attention and stock price overvaluation.

The authors find that there is a significant idiosyncratic volatility puzzle in China's stock market. Due to the role of mispricing, individual investor attention significantly enhances the idiosyncratic volatility effect, that is, as individual investor attention increases, the greater the idiosyncratic volatility, the lower the expected return. Attention can explain the idiosyncratic volatility puzzle in China's stock market. In addition, due to the role of information production and dissemination, securities analysts can reduce the degree of market information asymmetry and enhance the transparency of market information.

China is the second largest economy in the world, and few scholars analyze it from the perspective of investors' attention. The authors believe this paper has the potential in contributing to the academia.

Until recently, the Gulf Cooperation Council (GCC) region, whose members consist of Saudi Arabia, the United Arab Emirates, Kuwait, Qatar, Oman and Bahrain, has not significantly focused on the green transition. Specifically, wind energy development has made minimal progress relative to that of other regions.

The abundance of cheap fossil fuels in the region has not incentivized renewable energy development, and where this has taken place solar technologies are often preferred.

However, lower technology costs together with lost investment opportunities – also common elsewhere in the world, has increased the pressure on the GCC region from developers. This work qualitatively addresses the challenges and the strategies for the wind development in the area. It focuses on the analysis of different proposed type of investments – driven by a state-supported proposed fund – such as utility-scale investments, industry-specific investments, manufacturing investments and regional accelerators.

The work also suggests that Gulf sovereign wealth funds should act as the lead investors under new schemes, such as joint ventures, for wind development in the GCC, using their wealth to offering their populations with new sources of employment as well as energy that is sustainable.