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This paper aims to focus on the reliability of Sn15Bi–xAg and Sn15Bi–xCu solder joints during isothermal aging.

The effects of Ag or Cu additions on the microstructure, interfacial metallic compound layer and shear strength of Sn–15Bi (Sn15Bi) based solder joints during were investigated. The effects of Ag or Cu additions on the microstructure and tensile properties of Sn15Bi-based bulk solders were also investigated to provide a comprehensive analysis. The interfacial morphology and microstructure were observed by scanning electron microscopy and the composition in the structure was examined by energy dispersive spectrometer. The shear tests were carried out on the as-soldered and as-aged joints using a ball shear tester.

The results revealed that by adding Ag or Cu, the microstructure of Sn15Bi solder can be refined. Ag addition increased the tensile strength of Sn15Bi solder but had little effect on elongation. However, Cu addition decreased the tensile strength and elongation of Sn15Bi solder. For solder joints, Ag addition increased the shear strength and toughness of Sn15Bi/Cu joints but Cu addition decreased the shear strength and toughness of Sn15Bi/Cu joints.

The authors can potentially provide a replacement for Sn40Pb traditional solder with Sn15Bi solder by alloying Ag or Cu due to its lower cost and similar melting point as Sn–Pb solder.

High residual stress caused by the high temperature gradient brings undesired effects such as shrinkage and cracking in selective laser melting (SLM). The purpose of this study is to predict the residual stress distribution and the effect of process parameters on the residual stress of selective laser melted (SLMed) Inconel 718 thin-walled part.

A three-dimensional (3D) indirect sequentially coupled thermal–mechanical finite element model was developed to predict the residual stress distribution of SLMed Inconel 718 thin-walled part. The material properties dependent on temperature were taken into account in both thermal and mechanical analyses, and the thermal elastic–plastic behavior of the material was also considered.

The residual stress changes from compressive stress to tensile stress along the deposition direction, and the residual stress increases with the deposition height. The maximum stress occurs at both ends of the interface between the part and substrate, while the second largest stress occurs near the top center of the part. The residual stress increases with the laser power, with the maximum equivalent stress increasing by 21.79 per cent as the laser power increases from 250 to 450 W. The residual stress decreases with an increase in scan speed with a reduction in the maximum equivalent stress of 13.67 per cent, as the scan speed increases from 500 to 1,000 mm/s. The residual stress decreases with an increase in layer thickness, and the maximum equivalent stress reduces by 33.12 per cent as the layer thickness increases from 20 to 60µm.

The residual stress distribution and effect of process parameters on the residual stress of SLMed Inconel 718 thin-walled part are investigated in detail. This study provides a better understanding of the residual stress in SLM and constructive guidance for process parameters optimization.

Selective laser melting (SLM) is a promising additive manufacturing technology in the field of complex parts’ fabrication. High temperature gradient and residual stress are vital problems for the development of SLM technology. The purpose of this paper is to investigate the influence of substrate characteristics on the residual stress of SLMed Inconel 718 (IN718).

The SLMed IN718 samples were fabricated on the substrates with different characteristics, including pre-compression stress, materials and pre-heating. The residual stress at the center of the top surface was measured and compared through Vickers micro-indentation.

The results indicate that the residual stress reduces when the substrate contains pre-compression stress before the SLM process starts. Both substrate thermal expansion coefficient and thermal conductivity affect the residual stress. In addition to reducing the difference of thermal expansion coefficient between the substrate and the deposited material, the substrate with low thermal conductivity can also decrease the residual stress. Substrate pre-heating at 150°C reduces nearly 42.6 per cent residual stress because of the reduction of the temperature gradient.

The influence of substrate characteristics on the residual stress has been studied. The investigation results can help to control the residual stress generated in SLM processing.

The purpose of this paper is to bridge the knowledge gap in designing MBA strategy between China and the West by examining the content, context and process of MBA delivery. This paper challenges the assumptions and pedagogical approach underpinning the current design and delivery of MBA programmes that were originally moulded with Western management history and development in the era of globalization. There is consensus that MBA was used to train business managers; however, nowadays, people are inclined to state that MBA is used to develop global business leaders or full-fledged global competitors. How can we develop global business leaders without a global vision when designing MBA strategy?

Based on extensive literature review and critical analyses through the strategic management approach, this paper examines the status quo of current MBA programmes in the West and in China. This paper presents a conceptual framework that draws on the current MBA literature and on-going debates around management education and development in the West and in China.

The designing strategy of MBA has been originally strongly influenced by Western ideology and ethos. Therefore, the difficulties of management knowledge transfer are often explained through culture acclimatization and emphasize has been on cultural divergence rather than convergence. With synthesis between Western and Eastern management identified, we argue that the appropriateness and effectiveness of the traditional philosophy of MBA designing strategy based on Western management history has been challenged in the 21st century. The perception has fuelled criticism of business schools in the post-recession. They have come under fire for allegedly failing in their obligations to educate socially responsible business leaders (Barker, 2010). This leads to rethinking of the philosophy and vision underpinning the MBA designing strategy. A new philosophical approach – integration of Western management with Eastern philosophy has been under scrutiny, which is necessary in business education to enable future business leaders to become full-fledged competitors in the global market.

The output of this discussion helps to establish a conceptual framework which will provide strategic insight in enabling business/management school and MBA providers to address the current deficiency in MBA teaching and learning strategy and develop more appropriate arrangement when considering the design and development of a successful MBA programme in the 21st century.

To examine the nature of Chinese business negotiating style in Sino‐Western business negotiations in business‐to‐business markets involving large industrial projects from a social cultural point of view.

A conceptual approach developed from personal interviews.

This study reveals that the Chinese negotiator does not possess an absolute negotiating style but rather embraces a mixture of different roles together: “Maoist bureaucrat in learning”, “Confucian gentleman”, and “Sun Tzu‐like strategist”. The Chinese negotiating strategy is essentially a combination of cooperation and competition (termed as the “coop‐comp” negotiation strategy in this study). Trust is the ultimate indicator of Chinese negotiating propensities and role choices.

The focus of this study is on Chinese negotiating style shown in large B2B negotiations with Chinese SOEs.

Differing from most other studies on Chinese negotiating style which tend to depict the Chinese negotiator as either sincere or deceptive, this study points out that there exists an intrinsic paradox in Chinese negotiating style which reflects the Yin Yang thinking. The Chinese negotiator has a cultural capacity to negotiate both sincerely and deceptively and he/she changes coping strategies according to situation and context, all depending on the level of trust between negotiating partners.

There are many safety hazards in construction workplaces, and inattention to the hazards is the main reason why construction workers failed to identify the hazards. Reasonably allocating attention during hazard identification is critical for construction workers’ safety. However, adverse working environments in job sites may undermine workers’ attention. Previous studies failed to investigate the impacts of environmental factors on attention allocation, which hinders taking appropriate measures to eliminate safety incidents when encountering adverse working environments. This study aims to examine the effects of workplace noise and heat exposure on workers’ attention allocation during construction hazard identification to fill the research gap.

This study applied an experimental study where a within-subject experiment was designed. Fifteen construction workers were invited to perform hazard identification tasks in panoramic virtual reality. They were exposed to three noise levels (60, 85 and 100 dBA) in four thermal conditions (26°C, 50% RH; 33°C, 50% RH; 30°C, 70% RH; 33°C, 70% RH). Their eye movements were recorded to indicate their attention allocation under each condition.

The results show that noise exposure reduced workers’ attention to hazardous areas and the impacts increased with the noise level. Heat exposure also reduced the attention, but it did not increase with the heat stress but with subjects’ thermal discomfort. The attention was impacted more by noise than heat exposure. Noise exposure in the hot climate should be more noteworthy because lower levels of noise would lead to significant changes. These visual characteristics led to poorer identification accuracy.

This study could extend the understanding of the relationship between adverse environmental factors and construction safety. Understanding the intrinsic reasons for workers' failed identification may also provide insights for the industry to enhance construction safety under adverse environments.

The purpose of this paper is to design a climbing robot connected by a connecting rod mechanism to achieve multi-functional tasks such as obstacles crossing and climbing of power transmission towers.

A connecting rod type gripper has been designed to achieve stable grasping of angle steel. Before grasping, use coordination between structures to achieve stable docking and grasping. By using the alternating movements of two claws and the middle climbing mechanism, the climbing and obstacle crossing of the angle steel were achieved.

Through a simple linkage mechanism, a climbing robot has been designed, greatly reducing the overall mass of the robot. It can also carry a load of 1 kg, and the climbing mechanism can perform stable climbing. The maximum step distance of the climbing robot is 543 mm, which can achieve the crossing of angle steel obstacles.

A transmission tower climbing mechanism was proposed by analyzing the working environment. Through the locking ability of the screw nut, stable clamping of the angle steel is achieved, and a pitch mechanism is designed to adjust the posture of the hand claw.

This paper aims to explore the influence of founder shareholders’ resources on the allocation of control rights from the perspective of incomplete contract theory and resource-based theory.

This paper analyzes newspaper materials with NVivo11on a case of battle for corporate control in Chinese top-listed company-Vanke Group.

The research shows that human capital is the key resource and the holding proportion of financial resources directly affects the allocation of control rights. At the same time, social capital is unstable and easily broken. At last, institutional environment also affects the degree between the relationship of founder shareholders’ resources and the allocation of control rights. The influence of founder-shareholder resources on the allocation of control rights follows the path of “crisis – founder-shareholder’s resources – founder’s ability - allocation of control rights.”

This study only selects the financial capital, human capital and social capital of Shi Wang, the founder of Vanke, as the analysis object. The study can expand the types of founder shareholder resources to verify and enrich the conclusions.

The current theoretical research in the literature focuses on the necessity of equity and shareholder’s resources versus the control rights. Some key factors and mechanism on the relationship have not been fully clarified. The results of this paper not only extend the combination research of social network and corporate governance, but also provide enterprise founders with references for making reasonable decisions during control battle.