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Rotary disc is a key component in the compact spherical pump, connecting shaft and piston, bearing hydraulic force conformally and constituting dynamic working chambers alternatively. Motion of rotary disc comprises two components. One is rotating around its own axis and the other is sliding on a cone surface. Therefore, it is necessary to investigate the friction and wear mechanism between rotary disc and cylinder under a complicated operation condition.

Structural properties of rotary disc are analyzed first. Frictional moment of rotary disc is modeled based on its structural characteristics and working mechanism, and the constraints of the structural parameters are considered. Besides, the concept of dimensionless contact area is proposed. Comparison is performed between the proposed concept and the frictional moment to determine an optimized beginning angle for spherical pump with a given displacement. The wear model of rotary disc is also established based on its kinematic property, a velocity coefficient is proposed and its common values are presented.

Effects of structural parameters, i.e. beginning angle and ending angle on the frictional moment, are obtained quantitatively. The frictional moment increases with beginning and ending angle with different rates. While the dimensionless contact area decreases with beginning angle. The larger the piston angle, the larger the velocity coefficient will be. The rotary disc wears severely with a larger beginning angle and smaller ending angle, while it has the smallest wear rate under a smaller beginning angle and a larger ending angle.

The originality lies in modeling the complex contact force of rotary disc based on its specific structure. These conclusions can be used to optimize the structural parameters of rotary disc.

Because of the specific structure and working mechanism, piston speed is only half of its shaft, which causes severally friction between piston and cylinder. Therefore, the main purpose of this paper is to investigate the friction and wear characteristics of the incomplete spherical piston in spherical pump comprehensively. Finally, to search the low-friction and wear-resistance structural pattern of the piston, and enhance the durability of spherical pump.

The non-linear frictional moment model for incomplete spherical piston in spherical pump was derivated quantificationally. Parameter sensitivity analyses were conducted to find the low-friction structural pattern of the piston. The theoretical wear model of piston–cylinder pair is proposed as well.

To reduce the frictional moment between incomplete piston and cylinder, the optimised diameter ratio between piston pin and piston should be 0.12 based on the parameter sensitivity analyses. The maximum frictional moment is approximately 2.5 times of the minimum. The total efficiency should be considered synthetically based on the thickness of specific working medium.

The proposed non-linear frictional moment model offers the quantitative estimations. Parameter sensitivity analyses were conducted to find the low-friction structural pattern of the piston. The wear behaviours of the piston and cylinder were analysed to investigate the wear characteristics of the piston.

This paper aims to investigate the lubrication regime in spherical pump, especially under different structural parameters and operational conditions.

A ball-on-plane configuration is adopted to represent the contact model between spherical piston and cylinder cover. The governing equations, which include the Reynolds and elasticity equations, are solved and validated by Jin–Dowson model. Both minimum film thickness and lambda ratio (ratio of minimum fluid film thickness to combined surface roughness of the piston and cylinder cover) of the equivalent model are obtained using an established model.

The results indicate that piston diameter and radial clearance are the two main factors affecting the pump lubrication regime. Other related parameters such as rotation speed of the piston, load, viscosity of working medium, material matching and surface roughness of piston and cylinder cover also have different impacts on the lubrication regime of the spherical pump.

These results emphasize the importance of the design and manufacturing parameters on the tribological performance of spherical pumps and these are also helpful in improving the spherical pump lubrication regime and enlarging its life cycle. This is to certify that to the best of the authors’ knowledge, the content of this manuscript is their own work. This manuscript has only been submitted to this journal and never been published elsewhere. The authors certify that the intellectual content of this manuscript is the product of their own work and that all the assistance received in preparing this manuscript and sources has been acknowledged.

Compared with the traditional printed circuit board (PCB) drilling process, the technology of drilling IC substrate is facing more problems, such as much smaller hole diameter, more intensive hole space, thinner sheet and more complicated materials are drilled in process. Moreover, the base material of IC substrate is different from traditional PCB, more kinds of fillers added in IC substrate which make the drill worn seriously during drilling process. Micro-drills wear and micro holes quality are the most important questions when drilling IC substrate so far. Wear morphology of micro-drill, holes wall roughness and hole location accuracy are researched in this paper. The influence factors of micro-drills wear and micro holes quality are also studied in this drilling process. The paper aims to discuss these issues.

Two drills with same structure and different diameter are used to drill different stacks of IC substrate and drill different holes in this paper. There are four experiments made and the drilling parameters including spindle speed (n), feed rate (v_f) and retraction speed (v_r) are recommended by drill manufacturing company. Wear morphologies of drill are observed, holes wall roughness (R_max) and holes location accuracy (C_pk) are measured in this paper. Analyzing the main factors influence on drill wear, holes wall roughness and holes location accuracy through these experiments.

The micro-drills of IC substrate wear more severely compared with other material of PCB through the experimental results in this paper. Drill diameter has influence on micro-drill wear when drilling IC substrate, the smaller of drill is, the more severely of micro-drill wears. Drill diameter affect the holes wall roughness too, the holes wall roughness of larger holes is better than smaller one in a certain range. The drilled holes number also has influence on micro-drills wear, holes wall roughness and holes location accuracy. The more drilled holes, the seriously of micro-drills wear, and the worn drill would destroy the hole quality. Therefore, the more drilled holes lead the bad holes wall roughness and holes location accuracy in this paper. In addition, stacks of IC substrate affect much on the holes location accuracy, the more stacks, the worse holes location accuracy.

Chinese Mainland is obviously lagging behind in technology and manufacturer of IC substrate which is incompatible with the nation circumstances. There is few research of drilling IC substrate in China and research data are lacking so far. It is most necessary to improve the technology level of drilling IC substrate in China. In order to reduce the wear of micro-drills and improve the quality of micro-holes, many experimental tests about drilling IC substrate are researched in this paper.

The purpose of this study is to improve the mechanical property and processing performance and reduce the cost of the polylacticacid/polybutyleneadipate-co-terephthalate(PLA/PBAT) composites, the calcium carbonate (CaCO₃) and compatibilizer styrene-maleicanhydride copolymer (SMA-2025) were added to the PLA/PBAT system, and the effect of CaCO₃ and SMA-2025 on the morphology, structure, mechanical property, thermal property, thermalstability and shape memory property of the CaCO₃/PLA/PBAT composites were studied and discussed.

The CaCO₃/PLA/PBAT shape memory composites were prepared via melt-blending and hot-pressing methods, and the effect of CaCO₃ and SMA-2025 on the property of the composites was investigated via scanning electron microscope, universal testing instrument, Fourier transform infrared spectroscopy, differential scanning calorimetry, thermogravimetric analysis and DMA, respectively.

The interface property, mechanical property, thermal stability, shape memory recovery ratios and recovery stresses, and processing performance of the CaCO₃/PLA/PBAT shape memory composites were significantly improved by adding of CaCO₃ and SMA-2025. Moreover, the CaCO₃/PLA/PBAT composites have good blowing film processing performance.

This study will provide a reference for the research, processing and application of the high-performance CaCO₃/PLA/PBAT shape memory composites.

Since the “Standards + Certification” regional quality brand initiative has become a key component of China’s efforts to promote a quality-driven economy, this paper aims to examine the effect of perception, trust and satisfaction toward the regional quality brand on consumer loyalty.

Data were collected from 401 consumers who have bought “Zhejiang Manufacturing” regional quality brand products. The structural equation modeling (SEM) technique was applied to assess the relationship of the research model.

The results show that brand perception, trust and satisfaction toward regional quality brands all significantly positively impact both consumer behavioral and attitudinal loyalty. Further, the results confirmed that brand trust and satisfaction fully mediate the relationship between brand perception and behavioral loyalty and partially mediate the relationship between brand perception and attitudinal loyalty.

This study presents a conceptual model on the impact of perception toward regional quality brands on consumer loyalty in a field where little research has been done. It offers a consumer-focused analysis that advances the theoretical and empirical knowledge of regional quality brands.

The purpose of this paper is to investigate the effect of China’s image as a country on consumers’ evaluations of brands. Drawing on the literature pertaining to country images and country-of-origin effect, a research model was developed to evaluate country image, corporate image and brand image.

To test the model and investigate the effects of country, corporate and brand image on brand attitude and purchase intention, a survey was conducted that examined Korean consumers’ attitudes toward well-known Chinese brands.

China’s country image was found to comprise four dimensions: political image, economic image, citizen image and country relationship image. Country image had a direct positive effect on brand attitude, and through brand attitude, country image had an indirect positive effect on purchase intention. Corporate image and brand image had a positive effect on brand attitude and a direct positive effect on purchase intention. In addition, country image had a positive effect on corporate image, while through corporate image, country image had an indirect positive effect on brand image.

These findings not only offer theoretical evidence for research on China’s country image, but also provide empirical evidence to support the “going global” strategies of Chinese enterprises.

The size and complexity of China make the undertaking of research on the marketability of eco‐products in general a difficult task. However, it is assumed that cultural values significantly influence attitudes and behaviors. Therefore, this paper which uses a structural equation model, considers the extent to which Chinese people living in affluent cities in Southern China are found to have a low level of eco‐knowledge. It has identified that once the Chinese learn the hazards of eco‐unfriendly products to users and their family, they demonstrate a willingness to use greener products. The green consumption preferences also vary from product to product in China. Choosing the right eco‐product is the key to success. A case study related to the use of eco‐friendly insecticide has been used to demonstrate the marketability of eco‐products in China's affluent cities and is presented in this paper. The result may show a new horizon to green marketers.

This research explores the paradigm of coopetition and the different theories that contribute to its evolution. The variation of cooperation and competition in a relationship depends on the resource flows identified in the literature. However, this research focusses on coopetition behaviours in the business world. Coopetition, simultaneous collaboration, and competition between firms, has emerged as a pivotal factor influencing organisational success in today's dynamic business environment. Based on game theory, the different types of competitive relationships between adversaries will also be presented in this chapter, where the interdependencies between the players and their choices to co-operate or compete are explored. Another perspective presented is how companies use game theory to achieve gains in both zero-sum and non-zero-sum games by changing the players, the perceptions of risk, the associated returns, and the rules and scope of the game. This chapter also will show the prisoner's dilemma applied to business practices. Finally, we present the ‘tit-for-tat’ theory of strategy. The conclusion underscores the need for organisations to navigate a delicate balance between collaboration and competition to thrive in a complex and interconnected tourism global marketplace.

The purpose of this paper is to review the present status and relationship of Macau to Brazil and to a provide the historical context for that relationship.

This paper takes the approach of interviews, an extensive review of Portuguese and English language periodicals of Macau, Brazil, USA extending back to 1950s, and a review of the key secondary literature.

Efforts to promote a relationship between Macau and Brazil since 1961 have been laudable, but have not resulted in either a meaningful economic relationship or systematic cultural links.

Trade-wise Hong Kong is much better positioned to interface with Brazil than Macau. Brazil established strategic trade and diplomatic relations with China 25 years prior to Macau’s return to China in 1999 and without any intermediation by the city.

A strategic plan is needed to develop Macau’s links to Brazil based upon that country’s vast array of cultural strengths, which include sports, music, dance, religion, language, education, cuisine, environment resources, technology and the presence of a significant Macanese Diaspora.

There is a shortage of analysis on the status of the relationship of Brazil to China, Macau and the Lusophone world.