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The purpose of this paper is to synthesize a polyacrylate-based dispersant with a determined target molecular weight for oily systems and to determine the optimal dispersant level and monomer ratio of the dispersant.

The dispersant was synthesized by conventional radical polymerization using methacrylic acid, butyl acrylate and dimethylamino ethyl methacrylate as the monomer. It was characterized by Fourier transform infrared spectroscopy, nuclear magnetic hydrogen spectroscopy, gel permeation chromatography and thermogravimetric analysis. The dispersant was used to disperse TiO₂, and the performance of the dispersant was evaluated by measuring the viscosity, particle size and dispersive force of the slurry.

The dispersant exhibited high thermal stability and was successfully anchored to the surface of the TiO₂ pigment. When used to disperse a TiO₂ slurry, it effectively made the TiO₂ slurry more fluid, indicating its strong viscosity-reducing properties. The viscosity, particle sizes and dispersion capabilities of the TiO₂ slurry were found to vary depending on the contents and monomer ratios of the dispersant.

P(MAA-BA-DM) dispersant increases the wettability of TiO₂ only in oily solvents but not in aqueous solvents.

P(MAA-BA-DM) dispersant makes it easier to disperse TiO₂ pigments in oily solvents, increasing the amount of pigment in the solvent and making the preparation of highly pigmented pastes easier.

A dispersant containing suitable carboxyl and tertiary amine groups was initially synthesized to disperse TiO₂ in an oily system. The findings are anticipated to be used in the formulation of pigment concentrates, industrial coatings and other solvent-based coatings.

Using the theoretical frameworks of public diplomacy and public relations, we mapped how the Chinese government has used panda imagery to build its national brand on Twitter and how this ‘panda diplomacy’ has facilitated its para-diplomatic actions. Our findings uncover new attempts by the Chinese government to engage in digital diplomacy. Mobilizing panda imagery on Twitter enhanced friendly relations with foreign political leaders and people and established a friendly and peaceful image of China on Twitter.

The study aims to the distribution rule of lubricating oil film of full ceramic ball bearing and improve its performance and life.

The paper established an analysis model based on the fluid–solid conjugate heat transfer theory for full ceramic ball bearings. The distribution of flow, temperature and pressure field of bearings under variable working conditions is analyzed. Meanwhile, the mathematical model of elastohydrodynamic lubrication (EHL) of full ceramic ball bearings is established. The numerical analysis is used to study the influence of variable working conditions on the lubricant film thickness and pressure distribution of bearings. The temperature rise test of full ceramic ball bearing under oil lubrication was carried out to verify the correctness of simulation results.

As the speed increased, the oil volume fraction in full ceramic ball bearing decreased and the surface pressure of rolling element increased. The temperature rise of full ceramic ball bearings increases with increasing speed and load. The lubricant film thickness of full ceramic ball bearing is positively correlated with speed and negatively correlated with load. The pressure of lubricating film is positively correlated with speed and load. The test shows that the higher inner ring speed and radial load, the higher the steady-state temperature rise of full ceramic ball bearing. The test results are in high agreement with simulation results.

Based on the fluid–solid conjugate heat transfer theory and combined with Reynolds equation, lubricating oil film thickness formula, viscosity temperature and viscosity pressure formula. The thermal analysis model and EHL mathematical model of ceramic ball bearings are established. The flow field, temperature field and pressure field distribution of the full ceramic ball bearing are determined. And the thickness and pressure distribution of lubricating oil film in the contact area of full ceramic ball bearing were determined.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-05-2023-0126/

This paper aims to provide a bibliometric study of journal articles related to institutional repositories in the Social Sciences Citation Index (SSCI) between January 1993 and August 2017. This study will provide researchers with a foundation for further research.

In this study, articles published were analyzed; titles were searched using the term “institutional repositories.” The data were evaluated in response to four research questions on the following topics: publication trends, prolific authors, core journals and times cited.

The results indicate that 124 articles on institutional repositories were authored by 223 individuals. These articles were cited 722 times in 37 journals, and the h-index provided by the Web of Science was 14.

This study only investigated articles titled with institutional repositories in the SSCI. Other items were not included.

This study shows that the implementation of institutional repositories has been limited to library and information science. If they can be used broadly in different disciplines, a better outcome can be expected.

Based on the findings, the growth of institutional repositories as an academic subject is likely to continue. If such discussions can be conducted in other disciplines, institutional repositories may be able to provide a more promising outcome to academia.

This paper is valuable for researchers who wish to examine the trends of institutional repositories in the SSCI and seek possible areas for further research.

This paper aims to design an algorithm which is used to deal with non-linear discrete systems with constraints under the lower computation burden. As a result, we solve the non-holonomic vehicle tracking problem with the lower computational load and the convergence performance.

A fusion event-triggered model predictive control version is developed in this paper. The authors designed a shrinking prediction strategy.

The fusion event-triggered model predictive control scheme combines the strong points of event triggered and self-triggered methods. As the practical state approaches the terminal set, the computational complexity of optimal control problem (OCP) decreases.

The proposed strategy has proven to stabilize the system and also guarantee a reproducible solution for the OCP. Also, it is proved to be effected by the performance of the simulation results.

The purpose of this paper is to investigate the optimal production and financing strategies for the closed-loop supply chain (CLSC) composed of a capital-constrained original equipment manufacturer (OEM) and a risk-averse authorized remanufacturer (RM).

The authors formulate four models with different scenarios, namely, the OEM has sufficient capital; the OEM has limited capital without financing; the OEM adopts debt financing strategy; and the OEM adopts equity financing strategy. The equilibrium solutions of each scenario are obtained by backward induction method, the influences of risk aversion coefficient on the equilibrium solutions are examined and the OEM's optimal financing strategy is found by comparison analysis.

When the OEM's initial capital is limited and the equity dividend ratio is less than a certain threshold, the equity financing strategy is more advantageous for the OEM. However, if the OEM's initial capital is extremely scarce and the dividend proportion is large, the OEM prefers the debt financing strategy. When considering financing, consumer surplus always decreases as the risk aversion factor increases; the debt financing strategy is more environmentally friendly compared with the equity financing strategy. Only the debt financing strategy can make both members in the CLSC achieve a win-win situation in a certain region when the dividend ratio is sufficiently large.

It will be more fascinating if the model extends to such a case that the production operation situation in the CLSC composed of multiple OEMs in multiple periods. Furthermore, the remanufacturer's risk-averse information is asymmetry may be more realistic in our daily life.

There are three main differences from the existing research. One is that the remanufacturer's risk aversion originates from the uncertain remanufacturing cost instead of the uncertain market demand. Another is that the boundary conditions of the OEM prefer to adopt debt financing is obtained through the envelope theorem with Lagrange multiplier method. Last but not the least, this paper provides a good theoretical reference and practical guidance for the OEM to make the rational financing strategy selection in face of different degree of capital scarcity in the CLSC system. The value of the three aspects provides a theoretical basis for the optimal operation decisions of capital-constrained manufacturer considering the remanufacturer's risk aversion in the CLSC operation system.

In today’s turbulent and complex era, initiative behavior is becoming more drawn to construction projects but challenging to arouse as it is free of the established regulations in project practice. Given the prevalence of social media (SM) in modern workplaces, this study is thereby motivated to investigate whether and how SM use can act to drive initiative behavior of construction project members (PMs) in this context.

This study sharply examines two distinct types of SM use – work-related and social-related – to explore their roles in driving the initiative behavior of construction PMs. Additionally, self-determination theory is employed to explore their underlying translation mechanisms and associated boundary conditions. A survey dataset collected from 229 construction PMs is used to empirically test the proposed theoretical model.

Empirical results show that role-breadth self-efficacy, psychological safety and project identification, by satisfying basic psychological needs respectively, act as crucial bridging roles in translating SM use into initiative behavior of PMs. Such mediation effects are applied to both work-related and social-related SM use with varied mechanisms. Besides, prevention focus is found to be a contingent moderator on these relationships, with a strengthening role toward role-breadth self-efficacy and a weakening role toward project identification.

This study digs into the nuanced mechanisms of how SM use benefits construction projects, especially in terms of PMs’ initiative. The findings of this research afford new insights into effectively invigorating the initiative behavior of construction PMs under the current digital momentum.

This article aims to explore the geographic distribution of open access practices in the world from a diffusionist perspective.

The article applies a tempo‐spatial analysis to examine the diffusion movement of open access practices from the West to the entire world during the past several decades. Both maps and tables are used to support the analysis. The diffusionist theory is reviewed and applied to the understanding of open access.

The paper discovers that technology is not the only factor determining the diffusion pattern of information systems as discussed in the literature. Cultural dissimilarities across countries have played a significant role in open access development. Open access can only be effectively established after it meets local standards.

The findings help understanding of why open access has a disproportionate growth among developing countries, and even among developed countries, where the ICT infrastructure has been in place.

Few studies have taken a transnational view to analyze open access geography at the global level, and few have been able to synthesize models to interpret diverse discoveries. Furthermore, a chronological evaluation tracing the history of open access spatial expansion is absent in the literature.

High-speed turnouts are more complex in structure and thus may cause abnormal vibration of high-speed train car body, affecting driving safety and passenger riding experience. Therefore, it is necessary to analyze the data characteristics of continuous hunting of high-speed trains passing through turnouts and propose a diagnostic method for engineering applications.

First, Complete Ensemble Empirical Mode Decomposition with Adaptive Noise (CEEMDAN) is performed to determine the first characteristic component of the car body’s lateral acceleration. Then, the Short-Time Fourier Transform (STFT) is performed to calculate the marginal spectra. Finally, the presence of a continuous hunting problem is determined based on the results of the comparison calculations and diagnostic thresholds. To improve computational efficiency, permutation entropy (PE) is used as a fast indicator to identify turnouts with potential problems.

Under continuous hunting conditions, the PE is less than 0.90; the ratio of the maximum peak value of the signal component to the original signal peak value exceeded 0.7, and there is an energy band in the STFT time-frequency map, which corresponds to a frequency distribution range of 1–2 Hz.

The research results have revealed the lateral vibration characteristics of the high-speed train’s car body during continuous hunting when passing through turnouts. On this basis, an effective diagnostic method has been proposed. With a focus on practical engineering applications, a rapid screening index for identifying potential issues has been proposed, significantly enhancing the efficiency of diagnostic processes.

This article presents an advanced method for managing knowledge using a modular design approach and applied the approach through an example with computer manufacturing. The benefits of modularity are discussed both within and between companies. We find that through modular design, knowledge management systems are simplified and communication between modules is greatly improved. In addition, modularity makes parallel innovation possible, as well as, sharing innovative resources through collaboration. Modularity leads to effective knowledge sharing and thus stimulates knowledge-based innovation. A case study of the computer industry further demonstrates the effects of modularity in an industry. Finally, we suggest that enterprises should take advantage of modularity when they carry out knowledge-based innovation and the measures are developed to implement successful modularity.