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Pulse control, SEM analysis and metallographic examination have been used to record and study the process by which a ball is formed at the tip of an ultra‐fine copper wire. The process by which the copper ball is formed, and the laws governing this process, are presented.

In this paper, the process of forming copper wire balls in copper ball bonding has been studied by numerical analysis. By calculating the temperature field, speed field and displacement field for ultra‐fine copper wire under a miniarc, a regular pattern of copper wire ball formation has been observed. The calculation results for the displacement field has also been tested and verified.

The purpose of this paper is to investigate the design method of partial observer canonical form (POCF), which is one of the important research tools for industrial plants.

Motivated by the two-steps method proposed in Xu et al. (2020), this paper extends this method to the case of Multi-Input Multi-Output (MIMO) nonlinear system. It decomposes the original system into two subsystems by observable decomposition theorem first and then transforms the observable subsystem into OCF. Furthermore, the necessary and sufficient conditions for the existing of POCF are proved.

The proposed method has a wide range of applications including completely observable nonlinear system, noncompletely observable nonlinear system, autonomous nonlinear system and forced nonlinear system. Besides, comparing to the existing results (Saadi et al., 2016), the method requires less verified conditions.

The new method concerning design POCF has better plants compatibility and less validation conditions.

The purpose of this paper aims to design an optimization control for tunnel boring machine (TBM) based on geological identification. For unknown geological condition, the authors need to identify them before further optimization. For fully considering multiple crucial performance of TBM, the authors establish an optimization problem for TBM so that it can be adapted to varying geology. That is, TBM can operate optimally under corresponding geology, which is called geology-adaptability.

This paper adopted k-nearest neighbor (KNN) algorithm with modification to identify geological conditions. The modification includes adjustment of weights in voting procedure and similarity distance measurement, which at suitable for engineering and enhance accuracy of prediction. The authors also design several key performances of TBM during operation, and built a multi-objective function. Further, the multi-objective function has been transformed into a single objective function by weighted-combination. The reformulated optimization was solved by genetic algorithm in the end.

This paper provides a support for decision-making in TBM control. Through proposed optimization control, the advance speed of TBM has been enhanced dramatically in each geological condition, compared with the results before optimizing. Meanwhile, other performances are acceptable and the method is verified by in situ data.

This paper fulfills an optimization control of TBM considering several key performances during excavating. The optimization is conducted under different geological conditions so that TBM has geological-adaptability.

This study aims to review the current one-step electrodeposition of superhydrophobic coatings on metal surfaces.

One-step electrodeposition is a versatile and simple technology to prepare superhydrophobic coatings on metal surfaces.

Preparing superhydrophobic coatings by one-step electrodeposition is an efficient method to protect metal surfaces.

Even though there are several technologies, one-step electrodeposition still plays a significant role in producing superhydrophobic coatings.

Cavitation bubbles cannot be avoided in the hydraulic system. Because of instability of flow and variation of water pressure, the jet often occurs in a bubble collapse. This study aims to accurately predict the shape, velocity and time of the resulting jet, so as to inhibit cavitation erosion.

In the study, a theoretical model of cavitation bubbles in the water has been developed by applying a periodic water film pressure into the Rayleigh–Plesset equation. A fourth-order in time Runge–Kutta scheme is used to obtain an accurate computation of the bubble dynamic characteristics. The behavior of the proposed theory is further simulated in a high-speed photography experiment by using a cavitation bubble test rig. The evolution with time of cavitation bubbles is further obtained.

A comparison with the available experimental results reveals that the bubble evolution with time has a duration of about 0.3T0, that well predicts the expanding and compressing process of cavitation bubbles. The results also show that the initial bubble radius in the water influences the moving velocity of the bubble wall, whereas the perturbation frequency of the water pressure has less effect on the velocity of the bubble wall.

A theoretical model well predicts dynamic characteristics of cavitation bubbles. The bubble evolution with time has a duration of about 0.3T0, Initial bubble radius influences the velocity of bubble wall. Perturbation frequency has less effect on the velocity of bubble wall.

This paper answers, in the Chinese stock market, who can realize the “spot value” of corporate social responsibility (CSR).

The authors use event-study to build the research framework. Using CSR report content analysis, the authors measure the specification level of CSR disclosure. Applying the Baidu index, the authors mine Chinese investors’ profiles data to investigate retail investor heterogeneity closely.

The authors find strong evidence that the measure captures a behavioral bias in CSR pricing: firms that choose to disclose CSR report experience positive abnormal return more among retail investors than institutional investors, more among young investors than older, but no difference between female and male investors.

For Chinese public firms, the authors give them evidence that they can realize positive abnormal returns by applying certain CSR disclosure strategies. For Chinese investors, especially retail investors and youths, the authors ask them to rethink whether their positive evaluation of CSR is a rational trade-off choice or whether they are fooled by the “hedging mask” and “attention-grabbing.”

The findings can give some suggestions to regulators: encouraging voluntary disclosure and reducing mandatory disclosure can drive enterprises to engage in more CSR activities because the voluntarily CSR disclosure can realize both long-term value and “spot value.” Complementarily, a more rigorous CSR report auditing regulation can suppress the “greenwash” by increasing the “lying cost.”

Using behavioral finance theory, the authors connect the gap between neoclassical research on the “U-shaped” value realization of CSR and the increasing voluntary CSR disclosure in the Chinese market. The authors find that heuristic reason and emotionality orientation results in the Chinese “CSR-friendly” market.

The purpose of this paper is to analyze the influencing factors of patients’ financial burden through a case study of hospital on public‒private partnerships (PPP) model (Chaonan Minsheng Hospital of Guangdong Province) and provide some useful information to policymakers for better development of hospitals on PPP model.

There are total six indicators that are defined as patients’ financial burden, basing on the policy of “indicators of medical quality management and control on the third level large general hospital (2011 edition),” issued by Chinese Government. In total, 23 potentially influencing factors of patients’ financial burden for hospital on PPP model were chosen from the above policy. The five-year (2007‒2011) data for the above 29 indicators come from statistic department of hospital on PPP model. Grey relational analysis (GRA) was applied to analyze the influencing factors of patients’ financial burden for hospital on PPP model.

A clear rank of influencing factors of patients’ financial burden is obtained and suggestions are provided from results of GRA, which provide reference for policymakers of hospital on PPP model. The five main influencing factors of patients’ financial burden for hospital on PPP model, in sequence, are rescuing critical ill patients on emergency, rescuing critical ill inpatients, inpatient bed occupancy rate, working days per bed and medical building area.

The study on the influencing factors of patients’ financial burden for hospital on PPP model not only provides decision-making for policymaker of hospital and controlling of medical expenditure but also contributes to release patients’ financial burden for hospitals on PPP model.

This paper describes the parent–child relationships of upper-middle-class Chinese parents and their adolescent children who were “parachuted” to the United States for private high schools. With parents remaining in China and children in the United States, thousands of miles away, such a transnational educational arrangement complicates the already volatile parent–child relationships during the adolescent years. Through ethnographic interviews of 41 students and 33 parents, I demonstrate different forms of child–parent relationships in a transnational education setting: those who found that the further physical and temporal distance has brought the parent–child relationship closer through frequent communications, children who experienced “accelerated growth” yet questioned the necessity, and delicate parent–child relationships due to increasing transnational cross-cultural or intergenerational differences. These types of parent–child relationships are not comprehensive of all the lived experiences of the “parachute generation,” yet they shed new light on transnational education and the unintended emotional dimensions of educational migration. In a transnational context for an economically well-off group, parental absence or separation of children and parents is no longer a clear-cut concept and has different layers of meanings, taking into account the frequency of communication, duration of spring and winter breaks and the existence of third-party agents such as for-profit intermediaries (or educational consultants) and host families. The diverse patterns of parent–child relations reveal the heterogeneity and complexities of “doing family” across geographic spaces and global educational hierarchies, as well as the roles of communication technologies, the tempo of mobilities and educational intermediaries.

To utilize Bluetooth as a layer 2 multi‐hop subnet for global IP network, there are two missing protocols in current Bluetooth stack: network formation and routing. In this paper, we propose our network formation and routing protocols optimized for such Bluetooth subnset usage scenarios to fill this gap. In this paper, we first present some observations on performance degradations of Bluetooth PAN due to network topologies and topology change when radio independant protocols are implemented. And then we analyze the reason of performance degradation. Based on our analysis, we first propose a flexible scatternet formation algorithm under conference scenario for multi‐hop communication. By using proposed method, scatternet can be formed flexibly with star, mesh, or linked line based on several parameters like number of maximum piconets that a gateway Bluetooth device can participate, and whether loops are needed in the resulting scatternet to achieve better network performance. To utilize topology information in multi‐hop communication, we propose a Cross‐layer Optimized Routing for Bluetooth (CORB) CORB is a QoS‐extended AODV routing protocol with mainly two optimizations between networking layer and underlying Bluetooth MAC layer. The first optimization is to use a new load metric. (LM) in QoS routing protocol instead of number of hops in conventional best effort routing. LM is derived from estimation of nodes’ link bandwidth, which reflects the different roles of nodes in Bluetooth scatternet. This proposal helps routing protocol to bypass heavily loaded nodes, and find route with larger bandwidth. The second optimization is to adjust LM and some MAC layer parameters in response to the unstable network topology caused by movement and change of indoor radio condition. Finally, We present some simulation and experiment results based on implementation, which prove the effectiveness of our protocols.