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Surface acoustic wave (SAW) sensors have attracted great attention worldwide for a variety of applications in measuring physical, chemical and biological parameters. However, stability has been one of the key issues which have limited their effective commercial applications. To fully understand this challenge of operation stability, this paper aims to systematically review mechanisms, stability issues and future challenges of SAW sensors for various applications.

This review paper starts with different types of SAWs, advantages and disadvantages of different types of SAW sensors and then the stability issues of SAW sensors. Subsequently, recent efforts made by researchers for improving working stability of SAW sensors are reviewed. Finally, it discusses the existing challenges and future prospects of SAW sensors in the rapidly growing Internet of Things-enabled application market.

A large number of scientific articles related to SAW technologies were found, and a number of opportunities for future researchers were identified. Over the past 20 years, SAW-related research has gained a growing interest of researchers. SAW sensors have attracted more and more researchers worldwide over the years, but the research topics of SAW sensor stability only own an extremely poor percentage in the total researc topics of SAWs or SAW sensors.

Although SAW sensors have been attracting researchers worldwide for decades, researchers mainly focused on the new materials and design strategies for SAW sensors to achieve good sensitivity and selectivity, and little work can be found on the stability issues of SAW sensors, which are so important for SAW sensor industries and one of the key factors to be mature products. Therefore, this paper systematically reviewed the SAW sensors from their fundamental mechanisms to stability issues and indicated their future challenges for various applications.

This paper aims to, from a Taoism perspective, one of Chinese inveterate cultures and mindsets, add knowledge into how Chinese indigenous cultures and mindsets will affect the way of Chinese people perceive and process guanxi. Specifically, this paper outlines the mechanism of guanxi from a culture perspective. Cultures significantly affect local people behavior.

A mixed-methods survey (Study 1) – analyzed with one-way ANOVA – and interview (Study 2) – analyzed with grounded theory – were used to answer the research questions. In total, 248 surveys were collected for Study 1, and 34 interviews for Study 2 that were transcribed into a word file, which consists of 609 pages with 327,463 Chinese characters, were processed.

The findings show that guanxi is determined by positive and negative forces between instrumental and affective components. Further, two essential conditions – fitness of personality and clear contract, which would determine when a positive or negative force would emerge in a guanxi – were identified.

The main contribution is that this paper clarifies the guanxi mechanism based upon one of the most significant Chinese cultures and mindsets. Or guanxi is viewed from a new perspective – how Taoism affects Chinese people’s perception and evaluation of guanxi. This paper also finds evidence for the main arguments based upon the two studies.

This study examines how informal business networks achieve marketing goals in socially uncertain contexts. Drawing from multiple historical sources, Shangbangs, a type of business network that thrived in pre-1949 China, are analyzed.

The Critical Historical Research Method (CHRM) undergirds a study of Shangbangs’ historicity (i.e. their socio-historically embedded multiplicity, including organizational forms, activities and connotations.

As informal regional, professional, project-based, special-product-based or mixed marketing networks, Shangbangs relied on “flexible specialization” and coupled multiple business needs to market goods and services, business organizations, specific social values and, when necessary, to debrand business rivals.

This analysis extends theories about marketing networks by probing their subtypes, diverse marketing activities, multipronged channels and relationship building with social entities (including underground societies, business associations and guilds) in response to pre-1949 China’s market uncertainties. Substantiating an alternative approach to “flexible specialization” and marketing innovations within the pre-1949 Chinese economy shows how a parallel theoretical framework can complement western-based marketing theories.

This first comprehensive analysis of Shangbangs, an innovative historical Chinese marketing network outside the conventional market-corporate dichotomy, can inform theory building for marketing strategy-making and management conditioned by social contexts.

This study aims to investigate scholars’ roles in resolving environmental community conflict, as environmental community conflict is becoming an increasingly serious problem in contemporary China, and it explored the underlying factors and mechanisms that influence successful conflict resolution.

Based on a combination of three types of sources – interviews, participant observation and existing literature, the study compared and contrasted 35 cases through a two-stage study project with 25 environmental community conflict cases in the first stage and ten non-environmental cases in the second.

Results indicate that scholars serve seven roles in community conflict resolution: identification persons for potential sources of community conflict and supporters for the people who evaluate conflict problems before attempting to solve them; advisers for conflict protagonists; leaders of many knowledge-related activities; organizers of entrepreneurial activities for other community members; information brokers between community members and other stakeholders; representatives of the government, firms, community members and other stakeholders; and self-interested participants. While scholars’ participation is important for resolving community conflict, their actions are often not effective. Successful community conflict resolution involving scholars must satisfy eight underlying factors: local scholars’ sustained participation; high capacity; improvement on the organizational level of community members; emphasis on high efficiency knowledge and information transmission; effective finding and use of the community’s social capital; continual optimization on their action strategies; obtainability of some benefits; and non-local scholars’ sustained external support through social capital. The more closely these rules are followed, the more successful scholars’ participation in community conflict resolution will be.

The findings have practical implications for improving the effectiveness of scholars’ participation in community conflict resolution in contemporary China and even in other countries.

The purpose of this paper is to develop a novel multivariate fractional grey model termed GM(a, n) based on the classical GM(1, n) model. The new model can provide accurate prediction with more freedom, and enrich the content of grey theory.

The GM(α, n) model is systematically studied by using the grey modelling technique and the forward difference method. The optimal fractional order a is computed by the genetic algorithm. Meanwhile, a stochastic testing scheme is presented to verify the accuracy of the new GM(a, n) model.

The recursive expressions of the time response function and the restored values of the presented model are deduced. The GM(1, n), GM(a, 1) and GM(1, 1) models are special cases of the model. Computational results illustrate that the GM(a, n) model provides accurate prediction.

The GM(a, n) model is used to predict China’s total energy consumption with the raw data from 2006 to 2016. The superiority of the GM(a, n) model is more freedom and better modelling by fractional derivative, which implies its high potential to be used in energy field.

It is the first time to investigate the multivariate fractional grey GM(α, n) model, apply it to study the effects of China’s economic growth and urbanization on energy consumption.

With the discussion on the linear relationship of determined material parameters, this study aims to propose a new method to analyze the deformation mechanism.

A modified constitutive model based on the hyperbolic sine Arrhenius equation has been established, which is applied to describe the flow behavior of Ti-6Al-4V alloy during the superplastic forming (SPF).

The modified constitutive model in this work has a good ability to describe the flow behavior for Ti-6Al-4V in SPF. Besides, a deformation map of titanium material is obtained based on the parameters. As the supplement, finite element models of high-temperature tensile tests are carried out as the application of the constitutive model.

The relationship between constitutive model parameters and forming mechanism is established, which is a new angle in rheological behavior research and constitutive model analysis.

Variable stiffness structure can significantly improve the interactive capabilities of grippers. Shape memory alloys have become a popular option for materials with variable stiffness structures. However, its variable stiffness range is limited by its stiffness in two phases. The purpose of this paper is to enhance the manipulation capabilities of tendon-driven flexible grippers by designing a wide-range variable stiffness structure.

Constitutive models of shape memory alloy and mechanical models are used to analyze the performance of the variable stiffness structure. A separated solution was used to combine the tendon-driven gripper and the variable stiffness structure. The feed-forward control algorithm is used to enhance the control stability of the variable stiffness structure.

The stiffness variable capability of the proposed variable stiffness structure is verified by experiments. The stability of the feedback control algorithm was verified by sinusoidal tracking experiments. The variable stiffness range of 8.41 times of the flexible gripper was tested experimentally. The interaction capability of the variable stiffness flexible gripper is verified by the object grasping experiments.

A new wide-range variable stiffness structure is proposed and validated. The new variable stiffness structure has a larger range of stiffness variation and better control stability. The new flexible structure can be applied to conventional grippers to help them gain stiffness variable capability and improve their interaction ability.

Over the past decade internationalisation by banks from emerging market economies has accelerated. The purpose of this study is to examine the role of government and home country institutions in the international expansion process of Chinese commercial banks (CCBs).

By employing qualitative research method, data was collected via interviews from 30 senior managers based on a sample of 10 CCBs involved in international expansion over the 2001–2013 period.

The study finds that the Chinese government and home institutions play an important role in motivating CCBs’ internationalisation. Evidence from this research illustrates the effect institutional factors have in emerging economy firms’ internationalisation.

The managerial implication of these findings is that CCBs could take great advantage of government policy by developing proper internationalisation strategies and capabilities that would enhance CCBs’ competitiveness in global market. On the institutional front, removal of the institutional constraints imposed on Chinese banking industry is required. Using market-oriented management and regulatory rules rather than imposing administrative restrictions could therefore accelerate CCBs’ adaption and integration in the international market and enhance their competitive power.

The purpose of this paper is to explore the potential challenges in developing numerical methodologies for inverse problems and optimizations.

Summarizing previous research results mainly contributed by two research groups of Zhejiang University and Hong Kong Polytechnic University.

Computational intelligence plays an essential role in studying inverse problems and optimizations.

An up-to-date review on the current status of numerical methodologies, especially computational intelligences, for inverse problems and optimizations contributed by Chinese researchers.

Solder bumps for chip interconnections are downsizing from current approximately 100 µm to the expected 1 µm in future. As a result, the Cu-Ni cross-interaction in Cu/Solder/Ni solder joints will be more complicated and then strongly influence the growth of the intermetallic compounds (IMCs). Thus, it is critical to understand the fundamental aspects of interfacial reaction in micro solder joints. This paper aims to reveal the effect mechanism of reflow temperature and solder size on the interfacial reaction in Cu/Solder/Ni solder joints.

The Cu-Ni cross-interaction in the Cu/Sn/Ni micro solder joints with 50 and 100 µm solder sizes at 250°C and 300°C were observed, respectively. The line-type interconnects were soaked in silicone oil, and the temperature of the line-type interconnects was 250 ± 3°C and 300 ± 3°C, which were monitored by a fine K-type thermocouple, and followed by an isothermal aging process at various times. After aging, the specimens were removed from the silicone oil and cooled in the air to room temperature.

The major interfacial reaction product on both interfaces was (Cu,Ni)₆Sn₅, and the asymmetric growth of (Cu,Ni)₆Sn₅, evidenced by the thickness of (Cu,Ni)₆Sn₅ IMCs at the Sn/Ni interface was always larger than that at the Sn/Cu interface, resulted from the directional migration of Cu atoms toward the Sn/Ni interface under Cu concentration gradient. The morphology of (Cu,Ni)₆Sn₅ IMC at Sn/Cu interface was columnlike at 250°C, and which changed from columnlike to scallop with large aspect ratio at 300°C, while that at Sn/Ni interface gradually evolved from needlelike to the mixture of needlelike and layered at 250°C, and which evolved from needlelike to scallop with large aspect ratio at 300°C. The evolution of morphology of (Cu,Ni)₆Sn₅ is attributed to the content of Ni. Furthermore, the results indicate that the Cu-Ni cross-interaction was stronger with small solder size and relatively low temperature in the Cu/Sn/Ni micro solder joints.

The asymmetric growth of (Cu,Ni)₆Sn₅ in the Cu/Sn/Ni micro solder joints, evidenced by the thickness of (Cu,Ni)₆Sn₅ IMCs at the Sn/Ni interface, was always larger than that at the Sn/Cu interface. The morphology evolution of (Cu,Ni)₆Sn₅ IMC at both interfaces was attributed to the content of Ni. The Cu-Ni cross-interaction was stronger with small solder size and relatively low temperature in the Cu/Sn/Ni micro solder joints.