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This paper aims to review recent reports on mechanical properties of Sn-Bi and Sn-Bi-X solders (where X is an additional alloying element), in terms of the tensile properties, hardness and shear strength. Then, the effects of alloying in Sn-Bi solder are compared in terms of the discussed mechanical properties. The fracture morphologies of tensile shear tested solders are also reviewed to correlate the microstructural changes with mechanical properties of Sn-Bi-X solder alloys.

A brief introduction on Sn-Bi solder and reasons to enhance the mechanical properties of Sn-Bi solder. The latest reports on Sn-Bi and Sn-Bi-X solders are combined in the form of tables and figures for each section. The presented data are discussed by comparing the testing method, technical setup, specimen dimension and alloying element weight percentage, which affect the mechanical properties of Sn-Bi solder.

The addition of alloying elements could enhance the tensile properties, hardness and/or shear strength of Sn-Bi solder for low-temperature solder application. Different weight percentage alloying elements affect differently on Sn-Bi solder mechanical properties.

This paper provides a compilation of latest report on tensile properties, hardness, shear strength and deformation of Sn-Bi and Sn-Bi-X solders and the latest trends and in-depth understanding of the effect of alloying elements in Sn-Bi solder mechanical properties.

The purpose of this paper is to investigate growth kinetics of interfacial Cu-Sn intermetallic compound (IMC) at the solid Cu/liquid Sn interface.

The Sn/Cu solid–liquid interfacial IMCs are fabricated under various soldering temperatures (240°C-270°C) and soldering times (5-240 s) by dipping method. The thickness and morphology of IMC are observed and analyzed by the optical microscope and scanning electron microscope.

Holding at 260°C, Cu/Sn solid–liquid interface Cu₆Sn₅ growth index experience a change from 0.08 to 0.30 within 10-190 s. The growth index is 0.08 in 10-40 s; the growth index is 0.30 in 40-190 s. Cu₆Sn₅ grain coarsening index is constant within 10-190 s. It is 0.13. The result of the index of Cu₆Sn₅ grain coarsening is different from predecessors 27 results Cu₆Sn₅ grain coarsening index for 1/3. This is because Cu₆Sn₅ grain grows at the expense of its near small grain to reduce the surface Gibbs free energy, and its morphology changes from regular shape to irregular shape. It sets up the mathematical expression about the initial formation time and temperature of Cu₃Sn in 240°C-270°C.

It obtains a mathematical model to express the changes of solid–liquid interface frontier concentration which has an effect on the interfacial Cu₆Sn₅ layer growth index and the Cu₆Sn₅ grain coarsening index. Different indexes can be obtained by establishing relevance equations, which can be used to predict the growth of the interface IMC layer. This mathematical model is established to design the solder pads and the sizes of the solder joints.

This study aims to deliver a new perspective on how the interaction of independent and cooperative innovation affects firm digitization. Based on resource constraint theory, this study argues that the aforementioned interaction negatively affects firm digitization. The moderating role of managerial discretion is also discussed in light of the principles of the awareness-motivation-capability (AMC) framework.

The proposed hypotheses are empirically tested using a negative binomial modeling approach. The data used are from A-share listed companies in China’s Shanghai and Shenzhen stock markets from 2006 to 2020.

This study suggests that the interaction of independent innovation and cooperative innovation negatively impacts digitization. In addition, this study argues that environmental discretion and organizational discretion weaken the negative impact of the mentioned interaction on digitization. However, additional discretion in the Chinese context has no effect on above relationships.

This study explores the impact of the interaction of independent and cooperative innovation on digitization and incorporates managerial discretion into this framework based on the AMC framework.

Looks at consumer research in Greater China including Mainland China, Hong Kong and Taiwan. Maps out the contributions within this area and guides future research. Examines the state of the art over the 1979‐97 period, with particular emphasis on the topics that have been researched, the extent of the theory development in the field and the methodologies used in conducting research. Uses content analysis to review 75 relevant articles. Suggests that, while a considerable breadth of topics have been researched, there remains much to be done, there is further room for theoretical development in Chinese consumer behaviour studies; and the methodologies used need improvement and further refinement.

The aim of this paper is to investigate the effect of information asymmetry on revenue sharing contracts and performance in a dual-channel supply chain. First, the authors model the optimum revenue sharing contract in a dual-channel supply chain under both the full information case and the asymmetric information case. Second, they contrast the optimal decisions of a dual-channel supply chain between the full information case and the asymmetric information case. Third, they explore the impact of asymmetric cost information on the performance of a dual-channel supply chain and investigate the information value.

The authors present two main issues associated with revenue sharing contracts to alleviate manufacturer–retailer conflicts in a dual-channel supply chain. In the first issue, a revenue sharing contract is designed in a dual-channel supply chain under asymmetric cost information conditions, based on the principal-agent model. In the second issue, an optimal revenue sharing contract under full information conditions, based on the Stackelberg game is discussed. They explore the impact of asymmetric cost information on the performance of a dual-channel supply chain and investigate the information value based on comparative static analysis.

First, the direct sale price is unchanged and independent of the retailer’s cost construct, but the wholesale price increases and the retail sale price does not decrease under asymmetric cost information. The information asymmetry leads to higher direct sale demand and lower retail sale demand. Second, information asymmetry is beneficial for the retailer, but imposes inefficiency on the manufacturer and the whole supply chain. Third, the performance of the dual-channel supply chain is improved if the retailer’s cost information is shared and the dual-channel supply chain reaches coordination. The retailer is willing to share its cost information if the lump sum side payment that the manufacturer offers can make up the retailer’s reduced profit due to sharing this information.

The authors proposed a contract menus design model in a dual-channel supply chain. They examine how information asymmetry affects optimal policies and performance. They compared the optimal policies under symmetric information and asymmetric information. Conditions under which the partners prefer sharing information are identified. They quantified the information value from the points of partners and the whole system.

The purpose of this paper is to study the controller design of flexible manipulator. Flexible manipulator system is a nonlinear, strong coupling, time-varying system, which is introduced elastodynamics in the study and complicated to control. However, due to the flexible manipulator, system has a significant advantage in response speed, control accuracy and load weight ratio to attract a lot of researchers.

Since the order of flexible manipulator system is high, designing controller process will be complex, and have a large amount of calculation, but this paper will use the dynamic surface control method to solve this problem.

Dynamic surface control method as a controller design method which can effectively solve the problem with the system contains nonlinear and reduced design complexity.

The authors assume that the dynamic parameters of flexible manipulator system are unknown, and use Radial Basis Function neural network to approach the unknown system, combined with the dynamic surface control method to design the controller.

The success of online health communities (OHCs) depends on maintaining long-term relationships with physicians and preventing churn. Even so, the reasons for physician churn are poorly understood. In this study, an empirical model was proposed from a social influence perspective to explore the effects of online social influence and offline social influence on physician churn, as well as the moderating effect of their online returns.

The empirical data of 4,145 physicians from a Chinese OHC, and probit regression models were employed to verify the proposed theoretical model.

The results suggest that physicians' churn intention is influenced by online and offline social influences, and the offline social influence is more powerful. Physicians' reputational and economic returns could weaken the effect of online social influence on churn intention. However, physicians' economic returns could strengthen the effect of offline social influence on churn intention.

This research study is the first attempt to explore physician churn and divides the social influence into online and offline social influences according to the source of social relationship. The findings contribute to the literature on e-Health, user churn and social influence and provide management implications for OHC managers.

The paper aims to develop an efficient data-driven modeling approach for the hydroelastic analysis of a semi-circular pipe conveying fluid with elastic end supports. Besides the structural displacement-dependent unsteady fluid force, the steady one related to structural initial configuration and the variable structural parameters (i.e. the variable support stiffness) are considered in the modeling.

The steady fluid force is treated as a pipe preload, and the elastically supported pipe-fluid model is dealt with as a prestressed hydroelastic system with variable parameters. To avoid repeated numerical simulations caused by parameter variation, structural and hydrodynamic reduced-order models (ROMs) instead of conventional computational structural dynamics (CSD) and computational fluid dynamics (CFD) solvers are utilized to produce data for the update of the structural, hydrodynamic and hydroelastic state-space equations. Radial basis function neural network (RBFNN), autoregressive with exogenous input (ARX) model as well as proper orthogonal decomposition (POD) algorithm are applied to modeling these two ROMs, and a hybrid framework is proposed to incorporate them.

The proposed approach is validated by comparing its predictions with theoretical solutions. When the steady fluid force is absent, the predictions agree well with the “inextensible theory”. The pipe always loses its stability via out-of-plane divergence first, regardless of the support stiffness. However, when steady fluid force is considered, the pipe remains stable throughout as flow speed increases, consistent with the “extensible theory”. These results not only verify the accuracy of the present modeling method but also indicate that the steady fluid force, rather than the extensibility of the pipe, is the leading factor for the differences between the in- and extensible theories.

The steady fluid force and the variable structural parameters are considered in the data-driven modeling of a hydroelastic system. Since there are no special restrictions on structural configuration, steady flow pattern and variable structural parameters, the proposed approach has strong portability and great potential application for other hydroelastic problems.