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This study aims to analyse the geographical distribution of global research activities and to investigate the knowledge diffusion embodied in scientific papers.

The geographical summary of Frontiers articles displays the number of visits and categorizes where the visitors hail from. This study uses the records of 23,798 articles published in 16 Frontiers journals from 2007 to 2015 to analyse the geographical distribution of article visits at both country and city levels. The process of knowledge diffusion is investigated on the basis of the different visiting patterns of new and old papers.

Most article visits are concentrated around major metropolitan areas and some high-tech clusters. The top “visiting countries” include both developed countries and developing countries, and the USA and China are two major players. Publishing cities dominate article visits for new papers; as time passes, there is diffusion from the publishing cities to a broader area.

The data on visiting for open access articles may be generated from various repositories besides the publishers’ websites; these data are ignored, as they are not significant enough to have much influence. There is also a lack of a basic theory in the data processing of outliers in the data set. In addition, only static results are given in this paper, as the data were collected on one day, for one time. A longer time period is necessary to track the dynamic diffusion process of the observations.

Introduction of usage data will propose a novel way to analyse research activities and track knowledge diffusion.

The visiting data of articles offer a new way to investigate research activities at the city level in a detailed and timely manner, for the geographical distribution of research activities and the research resource allocation of a specific country to be explored.

This study measured the research activities of scientific papers by examining the usage data. Compared with previous studies that focused on the geographical distribution of scientific activities using publication data, citation data and even altmetrics data, usage data are at the forefront of this research. Therefore, usage data offer a fresh perspective on methodology, providing more detailed and real-time information.

The purpose of this paper is to find out the anti‐smoking counselling frequency and its correlates in a sample of Chinese physicians.

In this paper, 268 physicians in Baoding, a city near Beijing, filled out a questionnaire asking about their own smoking status, their anti‐smoking behaviors as well as their opinions on how to reduce cigarette smoking in China.

The paper finds that 54 percent of the male and 8.4 percent of the female physicians were current cigarette smokers. When asked whether they had counselled their patients about cigarette smoking in the past year, 43.7 percent answered “always”; 38.1 percent “often”; 13.1 percent “sometimes”; 2.6 percent “occasionally”, and 2.6 percent said: “not much”. However, only 9.0 percent said that they were “very successful”. Physicians' anti‐smoking counselling practices were highly correlated with their own smoking status; whether they perceived their past anti‐smoking activities as successful; whether they thought that they should set examples by not smoking; whether they felt that they had the responsibility to help patients and whether they perceived themselves as influential in persuading patients to quit smoking.

The paper shows that messages aimed at increasing Chinese physicians' anti‐smoking counselling should appeal to their responsibility, exemplary role, and unique influence on patients' health‐related behaviors.

The paper adds to the few studies on Chinese physicians' cigarette smoking behavior and their anti‐smoking activities. In a country where cigarette smoking is a way of life among males, and few people are aware of the health consequences of cigarette smoking, physicians' efforts can be a spearhead to a cessation campaign.

This paper aims to investigate the effects of low-viscosity and ultralow-viscosity engine oils on the comprehensive friction and fuel economy of turbocharged gasoline direct injection (TGDI) through simulation analysis and experiments.

Numerical analysis models of friction loss for reciprocating, crankshaft and valve train are established. Based on the FAST, the friction loss of 24 specific parts of a TGDI engine was analyzed. Finally, the engine test bench was built, which was used to test the mechanical loss, external characteristics and universal characteristics.

Compared with the baseline oil, lower viscosity lubricating oil can reduce the friction loss of nine components to varying degrees. When the viscosity decreases, the friction distribution ratio of reciprocating, crankshaft and balance shaft will gradually decrease. The proportion of reciprocating when using 0W12 is reduced by 4%. Tests have shown that ultralow viscosity engine oil reduces torque loss by up to 15.74% (2,000 rpm, full throttle), but its fuel consumption rate becomes higher in low-speed and high-torque conditions.

This work helps to understand the effect of lubricating oil characteristics on the comprehensive friction performance of the engine.

The purpose of this paper was to attempt to confirm the root cause of wafer damage issue by heavy Al wire wedge bonding and propose some permanent solutions for it.

The infra red–optical beam-induced resistance change (IR-OBIRCH) analysis defines the position of an abnormal hotspot. A cross section and an scanning electron microscope (SEM) confirmed the wafer damage issue and its position. Based on the position of wafer damage, the wedge tool with different life and Al buildup was checked found to be on the wedge tool. Finite element analysis (FEA) modeling analysis and simulation experiment guarantee the Al buildup, and low wedge deformation thickness (WDT) can cause the wafer damage issue. Finally, design of experiment (DOE) experiments are designed to optimize wedge tool dimension and wedge-bond parameters to eliminate wafer damage issue.

Wafer damage issue caused the Vpwr-OUTPUT leakage issue by IR-OBIRCH analysis. Al buildup was found on wedge tool with different life and its size gets larger along with the increase in wedge tool life. Low WDT and bigger Al buildup can cause the wafer damage. Designing new wedge tool and parameters optimization can increase WDT.

Because of the limitation of time and resources, finite element method (FEM) modeling and wedge tool dimension could not be studied more deeply.

This paper sets an example on how to find out the root cause of wafer damage by a step-by-step analysis and put forward a quick solution accordingly for the issue.

The purpose of this paper is to attempt to study the failure mechanism of BGA (ball grid array) Cu wire bond ball lift and specifically focused on substrate outgassing’s impact on Cu wire bonding quality and reliability.

The Galvanic corrosion theory has been widely adopted in explaining the failure mechanism of Cu ball bond lift issue during reliability test or field application in the presence of moisture. In this study, ion chromatography was performed on BGA substrate halogen analysis. EDX (energy-dispersive X-ray spectroscopy) was also used to detect the contaminant’s element at the bottom surface of a window clamp. Further FTIR (Fourier transform infrared spectroscopy) analysis verified that the contamination is from substrate outgassing during wire bonding. A new window clamp design proved effective in reducing the negative impact from substrate outgassing during wire bonding.

The solder mask in a fresh substrate contains a chlorine element. The chlorine can be detected in the BGA substrate outgassing during wire bonding by FTIR and EDX analyses, which have a negative impact on the Cu wire bonding. The window clamp with a larger opening can reduce the negative impact of the Cu wire bonding from the BGA substrate outgassing.

Because of the limitation of time and resources, bonding pad surface contamination from substrate outgassing and its correlation with Cu bonding ball lift failure after reliability test will be studied in depth later.

The BGA substrate outgassing has negative impacts on Cu wire bondability. A window clamp with a larger opening can reduce the negative impact from substrate outgassing.

Institutional factors play an important and complex role in Chinese outward foreign direct investment (OFDI) location choices that do not seem to be influenced by a host country’s high political risks. Moreover, the location choice for OFDI is key to corporate strategic decision-making on internationalization. Therefore, this study aims to examine the direct investments of Chinese multinational enterprises (MNEs) in Laos.

Combining the purposive sampling strategy and snowball sampling method, the authors interviewed nine market- and resource-seeking Chinese enterprises in Laos. Drawing from the mainstream eclectic paradigm and the theory of new institutional economics, the authors analyzed two key variables – enterprise investment motivation and enterprise heterogeneity.

Chinese MNEs are not insensitive to the regressive institutional quality of host countries; the relationship effect and institutional distance are the location decision pathways along with which institutional factors influence Chinese multinationals’ investments in Laos; political stability is necessary for Chinese-funded enterprises to invest in Laos and the degree of corruption is an overestimated institutional preference factor.

The relationship effect is introduced into the analysis framework as an intermediate variable that influences the decision of MNEs to invest in countries with underdeveloped institutions. It verifies the significant roles of bilateral political relations and network relations in the OFDI location decisions of state-owned and private enterprises, respectively.