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During the oil lubrication process of aviation herringbone gears, lubricating oil is injected into and spreads around the tooth surface. Its spreading characteristics directly affect the lubrication state and transmission efficiency of gears. This study aims to investigate the effect of changing the injection parameters and gear operating conditions on the oil film deposition during injection lubrication.

The computational fluid dynamics method was used to establish the computational domain for the simulation and optimization using an orthogonal test. The oil film spreading and thickness of the tooth surface were calculated with the change in gear speed, fuel injection distance and fuel injection speed. Optimized oil injection lubrication parameters were obtained, and design ideas were provided for the oil injection lubrication analysis of aviation herringbone gears.

Under different operating conditions, such as varying the injection speed, gear rotational speed and injection distance, there were differences in the distribution of the lubricating oil film formed on the tooth surface. The thickness of the oil film decreases as the distance from the injection port increases. The thickness of the oil film deposition can be increased by increasing the injection velocity and reducing the gear rotation speed. The injection distance had a relatively small effect on the spreading thickness of the deposited oil film, affecting only the dynamic spreading process of oil film deposition. Furthermore, the simulation results are compared with the analytical calculation results, and finally the experimental verification is carried out.

Oil spray lubrication characteristics are important for achieving precise gear lubrication designs in the aerospace field.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-08-2023-0250/

This paper aims to discuss major influencing factors causing users’ mobile social media fatigue and divides them into three hierarchies, including causal factors, intermediary factors and outcome factors. The study also sorts out connections between different levels of factors, thus providing effective guidance for the sustained development of social media.

Based on the grounded theory and by collecting data through in-depth interviews, the authors use open coding, axial coding and selective coding to analyze major influencing factors of users’ mobile social media fatigue, build a model using the software NVivo 11, organize and analyze mobile social media fatigue behavior and identify the relationships by combining the interpretive structural model and explore connections among the factors.

The influencing factors of mobile social media fatigue behavior conform with the stressors-strains-outcomes (SSO) theoretical framework, where stressors (S) include the five factors of fear of missing out, perceived overload, compulsive use, time cost and privacy concerns; strains (S) include the five factors of a low sense of achievement, emotional anxiety, reduced interest, social concerns and emotional exhaustion; outcomes (O) include the six factors of neglect behavior, diving behavior, avoidance behavior, tolerance behavior, withdrawal behavior and substitution behavior.

It focuses on the discussion of the interactions between users’ stressors, strains and outcomes without fully considering the impact of social environment and educational background on social media fatigue behavior. This study only focuses on one social media platform in the Chinese context, namely, WeChat. We reply on the qualitative research method to construct the relationships between social media fatigue factors because we were mainly interested in how users would respond psychologically and emotionally to social media fatigue behavior.

The study has extended the application of the SSO theory. Additionally, the research method and model used in this paper may serve as guidelines to other interested scholars who intend to explore relevant variables and conduct further research on the influencing factors of social media fatigue. In analyzing the causality of social media fatigue, the study has integrated the intermediary factor strain to display users’ strains from social media stress with a more detailed path discussion on the causality of social media fatigue, which has not received broad attention in previous research literature on social networking services users’ use.

In this study, text data are collected in a diversity of forms combined, allowing respondents to answer questions without being limited by the questions in the questionnaire, which helped us to identify new variables of social media fatigue. As a result, we were able to dig out the fundamental causes of social media fatigue and potential connections between the factors. Relevant scholars, users and businesses may analyze, manage and forecast users’ social media fatigue behavior by analyzing the type of social media stress and users’ state, providing guidance for the proposal of corresponding management strategies.

Most relevant studies focus on the sustained use of social media, and there is a scarcity of studies on social media fatigue in China. There is very limited research that conducts model analysis of social media fatigue through the integration of stressors, strains and outcomes.

The paper developed a novel gallic acid-based rust conversion emulsion (RCE) that is applied in the treatment of rusted steels. The purpose of this paper is to investigate the methods for the synthesis of RCE and study the mechanism of rust conversion.

Conversion emulsion was prepared using styrene, acrylate and self-developed gallic acid (GA)-based rust converter (GRC) via seed emulsion polymerisation. The polymerisable GRC was synthesised by the ring-opening reaction of glycidyl methacrylate with natural GA. The effects of the GRC dosage and its feeding modes on the RCE synthesis were analysed. The corrosion resistance, surface morphology, composition and mechanism of rust conversion coatings were studied using electrochemical tests, scanning electron microscopy, Raman spectroscopy and X-ray photoelectron spectroscopy (XPS), respectively.

The results showed that conversion coating on rusted steels treated with RCE, with various dosages of GRC (weight per cent), synthesised using seed emulsion polymerisation, exhibited the best adhesion and corrosion resistance. Raman spectroscopy revealed that RCE converted the original multiphase rust into stable crystalline phases of α-Fe₂O₃ and Fe₃O₄. According to XPS and energy dispersive X-ray analysis, the phenolic hydroxyl groups of RCE were proposed to chelate with Fe ions to form macromolecular ferrum compounds.

The pre-rusted steels demonstrated a better corrosion resistance than rust-free steels after treatment with RCE.

The paper developed a novel GA-based RCE with high efficiency and environment-friendly method.

This work is expected to replace the conventional rust conversion paints and cause a significant impact on extending the service life of rusted steels.

The paper aims to study the impact of cultural differences on the ownership structure of international joint ventures in China. It is reasoned that foreign investors, when faced with larger culture‐related investment uncertainties, may have the incentive to acquire more control rights to contain the risks by acquiring more equity shares in the joint ventures.

Data on international joint ventures in China were used to test the theory. The data contain 941 observations from Beijing, Shanghai, Shenzhen and Tianjing, covering a 13‐year time span. Pooled ordinary least square is used in the model estimation.

Cultural distance between China and foreign countries was found to increase the foreign equity share in the joint ventures, a finding contrary to traditional view. In addition, it was found that cultural distance in different dimensions does not play an equal role in affecting foreign equity shares. Last, there is significant evidence that the allocation of ownership between foreign and domestic investors in the joint ventures is influenced by the investor's relative importance in supplying different types of resources.

The paper introduces a new perspective into the study of culture and international joint venture. Foreign investors may be able to reduce investment risk by increasing equity shares, which gives them more internal control, in international joint ventures. In contrast, the traditional view is that larger cultural distance tends to discourage foreign equity ownership.

There is sufficient evidence to prove that the improved health status of a nation’s citizens results in economic growth and development via improved functionality and productivity of labor. It is also commonly accepted that healthcare expenditure significantly influences health status through, for instance, improving life expectancy at birth and reducing morbidity, death, and infant mortality rates. Within healthcare, medicines account for a considerable share of health-related expenditure in both developed and developing countries. Therefore, it seems reasonable to assume that improved access to medicines is likely to contribute not only to the well-being of families and individuals but also to the economic growth and development in all societies. It has been widely advocated that pharmaceutical multinational enterprises (MNEs) can play an important role to address this problem, as they develop and supply a significant proportion of the drugs imported by low- and middle-income countries. This chapter is dedicated to a systematic review of literature in order to identify the strategies implemented by pharmaceutical MNEs to improve access to medicines in the low- and middle-income countries. A total of 76 research articles have been identified, and we have found that the main strategies of pharmaceutical MNEs are related to improving health outcomes through R&D, establishing partnerships for product development, pricing strategies to improve access to medicines, technology transfer, licensing agreements, and nonmarket efforts to improve access to medicines, among other strategies to overcome barriers imposed by intellectual property rights. We have also found that pharmaceutical MNEs’ strategies take place within a complex system and often involve interactions with a wide range of actors, such as international organizations, governments, private not-for-profit sector, universities and research institutes, and generic manufacturers. However, there is still a need for major progress in the field of access to medicines, and pharmaceutical MNEs should be more active in this field in order to avoid potential negative consequences, such as loss of legitimacy and compulsory licensing of their patented medicines.

In many cross‐cultural management studies, culture and cultural differences across nations typically are assumed to be constant. The focus is on the impact of culture on other variables, such as the performance of multinational enterprises. However, is it possible that economic globalization results in cultural globalization? If yes, by how much? The purpose of this paper is to provide some evidence through studying the impact of foreign direct investment (FDI) on the Chinese culture.

An observable social indicator to represent each dimension of cultural value is chosen and statistical models are used to test whether FDI has significant impact on these indicators, after controlling for economic development level. Also this paper investigates whether FDI from a different cultural background has different effects on the Chinese culture.

Using data from major Chinese cities, it is found that FDI has significant effects on the degree of future orientation, performance orientation and in‐group collectivism. Also this paper found that FDI from the USA and the UK has a significant and negative effect on the degree of assertiveness; FDI from Japan, and Singapore, and the USA, and the UK has significantly negative effects on the degree of performance orientation; FDI from Japan and Singapore has a significantly positive effect on the degree of in‐group collectivism.

Unlike the traditional method of measuring culture values through what people say (interview or survey), this approach relies on what people do. This method helps avoid the measurement distortions caused by self‐deception and impression management problems with survey approach. In addition, this is believed to be the first study to test the impact of FDI on the change of culture values through econometric models.

This paper aims to propose a novel system design and control algorithm of lower limb exoskeleton, which provides walking assistance and load sharing for the wearer.

In this paper, the valve-controlled asymmetrical hydraulic cylinder is selected for driving the hip and knee joint of exoskeleton. Pressure shoe is developed that purpose on detecting changes in plantar force, and a fuzzy recognition algorithm using plantar pressure is proposed. Dynamic model of the exoskeleton is established, and the sliding mode control is developed to implement the position tracking of exoskeleton. A series of prototype experiments including benchtop test, full assistance, partial assistance and loaded walking experiments are set up to verify the tracking performance and power-assisted effect of the proposed exoskeleton.

The control performance of PID control and sliding mode control are compared. The experimental data shows the tracking trajectories and tracking errors of sliding mode control and demonstrate its good robustness to nonlinearities. sEMG of the gastrocnemius muscle tends to be significantly weakened during assisted walking.

In this paper, a structure that the knee joint and hip joint driven by the valve-controlled asymmetrical cylinder is used to provide walking assistance for the wearer. The sliding mode control is proposed to deal with the nonlinearities during joint rotation and fluids. It shows great robustness and frequency adaptability through experiments under different motion frequencies and assistance modes. The design and control method of exoskeleton is a good attempt, which takes positive impacts on the productivity or quality of the life of wearers.

Adopting adaptive behavior has become a basic measure for farmers because the increasingly severe climate change is affecting agricultural production. Perception is a critical first step in adopting adaptive behaviors. Livelihood resilience represents a farmer's ability to adapt to climate change. Therefore, this article aims to explore the impact of livelihood resilience and climate change perception on the climate change adaptation behavior of farmers in the Qinling Mountains region of China.

In this study, 443 micro-survey data of farmers are obtained through one-on-one interviews with farmers. The Logit model and Poisson regression model are used to empirically examine the impact of farmers' livelihood resilience and climate change perception on their climate change adaptation behaviors.

It was found that 86.68% of farmers adopt adaptive behaviors to reduce the risks of facing climate change. Farmers' perception of extreme weather has a significant positive impact on their adaptive behavior under climate change. The resilience of farmers' livelihoods and their perception of rainfall have a significant positive impact on the intensity of their adaptive behavior under climate change. Climate change adaptation behaviors are also different for farmers with different levels of livelihood resilience.

Based on the results, policy recommendations are proposed to improve farmers' perception of climate change, enhance the sustainability of farmers' adaptive behavior to climate change, strengthen emergency management and infrastructure construction and adjust and upgrade farmers' livelihood models.

The purpose of this paper is to analyze the mechanism of nanofluid enhanced heat transfer in microchannels and promote the application of nanofluids in industrial processes such as solar collectors, electronic cooling and automotive batteries.

The two-phase lattice Boltzmann method was used to calculate the flow and heat transfer characteristics of Al₂O₃ nanofluids in a microchannel at Re = 50. By comparing the simulation results of pure water, nanofluids without calculated nanoparticle-fluid interaction forces and nanofluids with calculated nanoparticle-fluid interaction forces, the effects of physical properties improvement and interaction forces on flow and heat transfer are quantified.

The findings show that the nanofluid (φ = 3%, R = 10 nm) increases the average Nusselt number by 22.40% at Re = 50. In particular, 16.16% of the improvement relates to nanoparticles optimizing the thermophysical parameters of the base fluid. The remaining 6.24% relates to the disturbance of the thermal boundary layer caused by the interaction between nanoparticles and the base fluid. Moreover, the nanoparticle has a negligible effect on the average Fanning friction factor. Ultimately, we conclude that the nanofluid is an excellent heat transfer working medium based on its performance evaluation criterion, PEC = 1.225.

To the best of the authors' knowledge, this research quantifies for the first time the contribution of nanoparticle-liquid interactions and nanofluids physical properties to enhanced heat transfer, advancing the knowledge of the nanoparticle's behavior in liquid systems.