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The MoS₂/graphite composite coatings modified by La₂O₃ through spraying technique were successfully prepared on the inner rings of spherical plain bearings. As a comparison, unmodified coatings were also prepared. This paper aims to study the La-modified MoS₂/graphite composite coating experimentally and improve the tribological performance of self-lubricating spherical plain bearings.

The performance of La₂O₃ toward the friction coefficient, temperature rise and wear rate of the coatings was studied by a self-made tribo-tester under different swing cycles. And the texture, surface morphology and element composition of the coatings were characterized by scanning electron microscope, energy dispersive spectroscopy and X-ray diffractometry.

The additives La₂O₃ refined the coatings’ microstructure and improved the tribological properties of the coatings. The oxidation of Mo + 4 to Mo + 6 was effectively inhibited. And the amount of abrasive grains, peeling pits and local cracks on the coatings surface decreased and homogeneous lubricating films formed, which were attributed to the existence of La₂O₃. The wear mechanisms of unmodified coatings were severe abrasive wear, adhesive wear and delamination wear. However, it exhibited superior wear resistance of the La-modified coatings to unmodified coatings, presenting slight abrasive wear and adhesive wear. The service life of bearings was prolonged under the protection of the modified coatings.

The paper proposed a new modified MoS₂/Graphite composite coating for the self-lubricating spherical plain bearings. The investigation on the friction, wear and temperature increase behaviors and the wear mechanisms of the coatings are beneficial to prolonging the service life of the self-lubricating spherical plain bearings.

The fabric self-lubricating liners are the key factors impacting the performances of self-lubricating spherical plain bearings. The purpose of this paper is to improve the friction and wear properties of self-lubricating radial spherical plain bearings by modification of the liners.

The liners of hybrid woven PTFE/Kevlar fabrics were treated respectively by the LaCl₃ and CeO₂ solutions. The tribological properties of self-lubricating spherical plain bearings with treated or untreated liners under continuous swaying conditions were investigated with the bearing tester at the swaying frequency of 2.5 Hz and the swaying angle of ±10°. The film formation and wear mechanisms were analyzed based on the observation of worn surfaces with a scanning electron microscope (SEM) and an energy dispersive spectrometer (EDS).

Results show that the tribological properties of the bearings treated by the LaCl₃ or CeO₂ solution were improved compared with those of the untreated bearings. In particular, the wear resistance of bearings treated by the CeO₂ solution was remarkably improved under higher swaying cycles, but the anti-friction properties and cooling effects of bearings treated by the LaCl₃ solution were better under lower swaying cycles. Through SEM analysis, the reasons were analyzed. The bearings with treated liners only produced slight adhesive and abrasive wear, but the bearings with untreated liners produced more serious adhesive and abrasive wear under higher swaying cycles.

The paper proposed a new pretreatment process for the self-lubricating liners. The investigation on the friction and wear behaviors of the bearings is beneficial for prolonging the service lives of the radial spherical plain bearings.

The prediction model to estimate the stability of a rotor-bearing system is established, which can predict the stability of gas bearings by applying Routh–Hurwitz stability criterion. This paper aims to provide the theoretical foundation for controlling actively the bearing running stiffness and damping and stemming the instability of a gas film.

The nonlinear dynamic lubrication analysis mathematical model of spherical hybrid gas bearings is established. Perturbation control equation is derived by the partial derivative method. The finite difference method is used to discrete the perturbation control equation in generalized coordinate system, and the difference expression of perturbation pressure is derived. The relational expression which involves the relationship between the dynamic characteristic coefficients of HSGHGB systems and perturbation pressure is deduced. So, the transient perturbation pressure distribution of a three-dimensional micro gas film, nonlinear gas film force, dynamic stiffness and dynamic damping coefficients of bearings are numerically computed using VC++6.0 programs.

The results show that the influence of supply pressure, speed and eccentricity on the dynamic characteristics of bearings is significant.

The influence law of supply pressure, speed and eccentricity ratio on the dynamic stiffness and damping coefficients of HSGHGB systems is researched. The prediction model to estimate the stability of rotor-bearing system is established, which can predict the stability of gas bearings by applying the Routh–Hurwitz stability criterion.

Nanocomposites represent a new prospective branch in the huge field of polymer materials science and technology. It has been shown that an overall enhancement of properties of polymers can be achieved under certain conditions by the addition of nanoparticles. To examine the influence of microstructure on the tribological performance of nanocomposites, different ways of compounding were used in this study. It was found that the friction and wear behavior of polymeric nanocomposites under sliding environment was rather sensitive to the dispersion states of the nanoparticles. When the microstructural homogeneity of the nanocomposites was improved, their wear resistance could be increased significantly. The present work demonstrates the importance of TiO₂‐nanoparticles dispersion in an epoxy resin matrix, on the materials’ tribological properties, when sliding against a smooth steel counterpart.

The purpose of this paper is to introduce a progressive strategy of the National Palace Museum (NPM) using new media art exhibitions as a creative marketing tool to interpret its collection, generate cultural value and navigate the greater global context.

A review of museum marketing literature and the challenges presented by Taiwan’s sociopolitical situation contextualize discussions on marketing activities and the emergence of museum-commissioned new media art at the NPM within the past two decades.

Democratic potency inherent in the digital medium has enabled the NPM to transcend the conflicting cultural perceptions surrounding its collection and fulfill the function of market expansion and cultural transmission.

Specialized heritage museums, such as the NPM, do not traditionally create or collect contemporary artworks that engage in ongoing cultural dialogues. This paper brings into view the novelty of using the digital medium to generate cultural value as exemplified in the new media art commissioned by the NPM.

This paper aims to establish an organizational learning system model based on both western and Chinese management thoughts.

The approach is a conceptual model which is based on research within the field.

The model consists of nine interrelated organizational learning sub‐systems including “discovering”, “innovating”, “selecting”, “executing”, “transferring”, “reflecting”, “acquiring knowledge from environment”, “contributing knowledge to environment”, and “building organizational memory” ones. The evidences in some famous Chinese traditional cultural classics (including Great Learning, Doctrine of the Mean, The Analects of Confucius, Book of Change, Tao‐Te‐Ching, The Art of War and Chuan‐Xi‐Lu) that support the rationale of the model are described and analyzed.

Several propositions are developed and it is hoped that the model is applicable in both eastern and western business environments.

In the cloud-computing environment, privacy preservation and enabling security to the cloud data is a crucial and demanding task. In both the commercial and academic world, the privacy of important and sensitive data needs to be safeguarded from unauthorized users to improve its security. Therefore, several key generations, encryption and decryption algorithms are developed for data privacy preservation in the cloud environment. Still, the outsourced data remains with the problems like minimum data security, time consumption and increased computational complexity. The purpose of this research study is to develop an effective cryptosystem algorithm to secure the outsourced data with minimum computational complexity.

A new cryptosystem algorithm is proposed in this paper to address the above-mentioned concerns. The introduced cryptosystem algorithm has combined the ElGamal algorithm and hyperchaotic sequence, which effectively encrypts the outsourced data and diminishes the computational complexity of the system.

In the resulting section, the proposed improved ElGamal cryptosystem (IEC) algorithm performance is validated using the performance metrics like encryption time, execution time, decryption time and key generation comparison time. The IEC algorithm approximately reduced 0.08–1.786 ms of encryption and decryption time compared to the existing model: secure data deletion and verification.

The IEC algorithm significantly enhances the data security in cloud environments by increasing the power of key pairs. In this manuscript, the conventional ElGamal algorithm is integrated with the pseudorandom sequences for a pseudorandom key generation for improving the outsourced cloud data security.

The purpose of this paper is to provide the historical background of genealogical records and analyze the value of Chinese genealogical research through the study of names and genealogical resources.

The paper examines the historical evolution and value of Chinese genealogical records, with the focus on researching the Islamic Chinese names used by the people living in Guilin. The highlight of this paper includes the analysis and evolution of the Islamic Chinese names commonly adopted by the local people in Guilin. It concludes with the recommendations on emphasizing and making the best use of genealogical records to enhance the research value of Chinese overseas studies.

The paper covers the history of Islam and describes how the religion was introduced into China, as well as Muslims' ethnicity and identity. It also places focus on the importance of building a research collection in Asian history and Chinese genealogy.

This research study has a strong subject focus on Chinese genealogy, Asian history, and Islamic Chinese surnames. It is a narrow field that few researchers have delved into.

The results of this study will assist students, researchers, and the general public in tracing the origin of their surnames and developing their interest in the social and historical value of Chinese local history and genealogies.

The study of Chinese surnames is, by itself, a particular field for researching the social and political implications of contemporary Chinese society during the time the family members lived.

Very little research has been done in the area of Chinese local history and genealogy. The paper would be of value to researchers such as historians, sociologists, ethnologists and archaeologists, as well as students and anyone interested in researching a surname origin, its history and evolution.

The purpose of this paper is to investigate the mechanism of transmitting economic policy uncertainty (EPU) shocks to capital structure.

The authors adopt a novel approach that bridges the asset pricing implications of EPU and the debt-financing decisions of Chinese firms by introducing a variable “policy-risk-induced equity return” (PRER). PRER is the product of the EPU beta and the EPU shock. Differentiating firms as per the signs of the EPU beta helps to shed light on the deep questions of whether their respective leverage targets and speeds of adjustment are different and how the targets and speeds are determined.

The empirical evidence shows that it is the equity market that channels EPU shocks to capital structure through PRER in China. Firms with positive (negative) EPU betas have PRER impact negatively (positively) the leverage target, conforming to the market-timing theory. EPU and non-policy uncertainty shocks cause the speed of adjustment to change over time. Overall, the intertemporal relation between EPU and leverage is negative. These results are robust to alternative leverage measures and after controlling for non-policy uncertainty shocks and conventional firm characteristics and have implications for academic research, policymaking, market stability, and corporate financing.

This study is the first to probe for, and provide insights into, the underlying reason why EPU impacts capital structure by connecting asset pricing to corporate financing for a large sample of Chinese publicly traded firms.

This paper aims to provide feasible countermeasures for the application of lean manufacturing in automatic sand casting workshops to optimize production line balance.

A production line balance optimization model for sand casting workshops is proposed. The value stream mapping (VSM) approach is applied to diagnose the problems in the production process. An optimization scheme is established based on eliminate, combine, rearrange, simplify and increase theory and Kanban management method. Further, simulation is done to compare current VSM and future VSM.

After implementing the proposed model, findings indicated that the idle time of equipment was effectively reduced, the line of balance of the production line was increased by 44.7%, the production lead time was shortened by 60.3% and the production capacity was increased by 50.0%.

Application of the optimization model in this study is limited to sand casting workshops that have realized automatic or semi-automatic production.

This paper provides an optimization model for the implementation of lean manufacturing in sand casting workshops and provides a reference case that reflects the actual application of lean manufacturing tools in a real situation.