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In this paper, a formula for life prediction of SMT solder joints under thermal cycling has been established on a damage model. The major failure mechanisms such as fatigue, creep and atmospheric oxidation have been considered in the formula. The experimental verification shows that the life formula established in this paper coincides with the experimental results.

Special education in China has lagged behind regular education for many years, however, the past few decades, the government has made considerable efforts to develop and improve the special education system. While the citizens of China have had a generic moral interest in disability since ancient times, the development of special education schools did not occur until American and European missionaries started schools for the visually and hearing impaired in the 19th century. The next major influence in the development of the special education system occurred with China’s Cultural Revolution in 1978. Interestingly, there is not any exclusive legislation on special education but in the 1980s, the government started Learning in Regular Classrooms (LRC), which is China’s version of inclusion. LRC has progressed rapidly the past two decades; however, the quality of instruction is low due to a lack of specialists, a shortage of personnel, inadequate funding, and limited technology as well as other barriers that are delineated in the chapter. The chapter emphasizes the government’s recent efforts in in-service teacher training, the preparation of preservice teachers, working with families, developing community rehabilitation training programs, and implementing evidence-based practices. Special education in China today is at a good place but it has quite a way from the ideal situation.

This paper presents a viscoelastic model for analysing the mechanical behaviour of SnPb solders which has been developed by combining grain boundary slip with viscoelasticity theory. On the basis of the model, and by using Boltzmann's integral constitutive equation of viscoelasticity, the mechanical behaviour (i.e., the relationships between stress (load) and strain (displacement)) of SnPb solders for one‐dimensional shearing deformation has been investigated and experimentally verified.

This paper explores the contextual factors involved in the development and application of paradigmatic theories in general, and the application and development of Agency Theory in the Chinese context in particular.

Referring to four templates for the design of conceptual papers as outlined by Jaakkola (2020), i.e. theory synthesis, theory adaptation, typology and model – we adopt an approach combining theory/literature synthesis and model establishment. Based on a thorough analysis and discussion of the literature on the topics of “context effect “, “interface between theory and context”, “special characteristics of Chinese context” and “invalid application of Agency Theory in a Chinese context”, we use Agency Theory as the lens to discuss the importance of context in applying and developing paradigmatic theory specifically. We start from the contextualization of Agency Theory and then explore approaches to theorizing the Chinese context by developing a conflict coefficient model.

First, the application validity of paradigmatic theories is not sustainable; contextual factors are critical in applying and developing not only propositional but also paradigmatic theories, such as Agency Theory. Second, the Chinese context requires special attention when applying paradigmatic theories originating from Western countries. Third, the traditional application logic of Agency Theory is invalid in the Chinese context due to the coexistence of principal-agent conflicts (PAC) and principal–principal conflicts (PPC), and changeable dominance status of two conflicts according to the contexts. Based on these observations, a model of contextualization theory of PAC and PPC (i.e. conflict coefficient model) is developed from a dynamic perspective, which connects the separated situation states and allows the identification and measurement of the relative severity of the two types of agency conflicts.

Practitioners can also use this model to identify and measure the relative strength of the two conflicts and determine the direction of control and improvement. Moreover, analysis of Chinese context and agency problems of Chinese firms also has great practical significance considering the increased importance of the Chinese market and the increasingly important role played by Chinese firms in the international economy in general, and in specific host countries in particular.

First, in general, this study expands Whetten's (2009) study of the interface between theory and context. It specifically discusses approaches to considering contextual factors in the development and application of the relatively overlooked paradigmatic theories, using traditional and widely used Agency Theory as a lens. Our study suggests that typical Agency Theory, developed based on Western-centric assumptions, does not completely hold in the context of Chinese business practices because of different cultural, legal and governance realities. Second, it improves and extends the application of Agency Theory by proposing the new perspective that PAC and PPC coexist in specific contexts and positing that the relative severity of two types of agency conflicts depends on the context variables. Third, it puts forward a conflict coefficient model offering a more comprehensive, intuitive and quantifiable method for comparing the extent of the two conflicts in different scenarios, providing a reference for empirical studies of corporate governance.

Self-organization has been regarded as a tool for the synthesis of well-defined organic nanostructures. Heterocyclic annulated perylene diimides are the subjects of considerable current research studies. The purpose of this study is to reveal the photophysical property, electronic structure and solid-state packing of O-heterocyclic annulated perylene diimide.

Asymmetrically five-membered O-heterocyclic annulated perylene diimide (OAPDI) was synthesized. Structure and purity of OAPDI were confirmed by ¹H NMR, ¹³C NMR, IR and mass spectral techniques. Photophysical properties of OAPDI were studied using UV–vis absorption and fluorescence in both solution (CHCl₃) and solid state. Scanning electron microscopic and atomic force microscopy were used to characterize the surface morphology of OAPDI. Conducting properties of the OAPDI were evaluated by current–voltage measurements. The compounds geometries were also optimized at 6-31G* using density functional theory.

The UV–vis absorption and fluorescence spectra of OAPDI in solution are blue-shifted in comparison with that of unsubstituted perylene bisimide. Solid-state UV–vis measurements of OAPDI indicate that it is capable of forming highly ordered structure. The non-covalent interactions, electrostatic attraction and p-p stacking moieties of OAPDI synergistically guide assembly and domain growth while maintaining the interpenetrating network of nanofibers in the solid film. The OAPDI gave higher current at −2.0 V (0.68 µA) and 4.0 V (1.0 µA).

This study will be helpful for exploring feasible routes to acquire soluble perylene diimides and well-defined organic nanostructures. Furthermore, such molecular tailoring approach would be helpful for designing and synthesizing novel organic semiconductive materials with excellent charge-transporting and light-emitting capabilities.

Political economy of trade policies and tariffs can affect welfare distribution and resources allocation as well as sustainable development. Political economy of trade between two countries can be affected by trade between other countries. Global trade can be affected by the bilateral trades of the countries. Impact of their bilateral trades on the global economy and global trade can be increased in case these two particular countries have big share in and influence on the global economy. Based on an in-depth literature review, this chapter aims to investigate political economy of the trade tariff and trade policies with particular focus on China’s economy, US, and China trade policies as well as their roles and impacts on global policy. Furthermore, recommendations for future trade policies and trade tariff strategies have been provided for enhancing global wealth and sustainable development. This chapter emphasizes the importance of sustainability in trade and trade policies’ roles in efficient resource allocation, welfare increase, and sustainable delvelopment. Furthermore, trade policies, taxes, and tariffs are recommended to be balanced based on the mutual trust, and common goals among trading countries. This chapter further emphasizes that trade policies need to promote ­sustainable supply globally.

SNS, namely social networking sites, has become one of the most effective and fast channels of information diffusion and dissemination. As an influential way of online marketing, SNS has been increasingly used by tourism organizations and enterprises to shape their destination image. On the basis of previews literature of destination image and SNS, this paper used the text analysis software ROST Content Mining (ROST CM) System to do a case study of the SNS destination marketing of Singapore on Chinese market. The authors analyze the text related to Singapore tourism on the major SNS in mainland China: Renren, Sina Weibo, and Douban, through word frequency analysis and the social semantic network, to summarize the destination image of Singapore on SNS. The paper also focuses on the difference of image building by official and individual SNS. Results found by this paper can be used by the relevant tourism organizations and enterprises to improve their destination marketing and image building on SNS channels.

Oversupplied emission basically will create a global economic downturn, which will lead to the implications for the climate action more broadly. Though the pandemic has test the resilience of carbon initiatives, there is urgency in identifying the carbon tax to strengthen as jurisdiction around the world ambitious in adopting and mitigating the targets as an introductory of the associated policy tools. Based on different situations and disciplines, the carbon tax model is simulated in different ways. The purpose of this study is to compare the available approaches that have been utilised by researchers and to determine the methods that suitable the most. The carbon tax and its influence on the construction sector are being benchmark and discussed as the whole of this document. A bibliometric approach is the method in this study in between the keyword of a carbon tax and the construction industry based on the data available in database of Scopus and Web of Science to foresee the interconnection between the knowledge of understanding and definition. The definition of carbon tax is the Pigovian tax that is designed to reduce the greenhouse gases (GHGs) emitted with aim to act as a green tax and been paid by the industries that emitted GHGs as for the carbon emission reduction agenda. The implementation is parallel to the other government policies and in sync to the sustainable development goals.

An installation has been developed for carrying out thermal cycling experiments on soldered SMT joints. Using this thermal cycle installation (which was developed by the authors) and a simulated chip carrier, study has been made of the influence of various factors on the reliability of soldered SMT joints during thermal cycling. These factors include the position of the soldered joint, the temperature range of the thermal cycle, the dwell time, etc.

The purpose of this study is to introduce the reproducing kernel algorithm for treating classes of time-fractional partial differential equations subject to Robin boundary conditions with parameters derivative arising in fluid flows, fluid dynamics, groundwater hydrology, conservation of energy, heat conduction and electric circuit.

The method provides appropriate representation of the solutions in convergent series formula with accurately computable components. This representation is given in the W(Ω) and H(Ω) inner product spaces, while the computation of the required grid points relies on the R_(y,s) (x, t) and r_(y,s) (x, t) reproducing kernel functions.

Numerical simulation with different order derivatives degree is done including linear and nonlinear terms that are acquired by interrupting the n-term of the exact solutions. Computational results showed that the proposed algorithm is competitive in terms of the quality of the solutions found and is very valid for solving such time-fractional models.

Future work includes the application of the reproducing kernel algorithm to highly nonlinear time-fractional partial differential equations such as those arising in single and multiphase flows. The results will be published in forthcoming papers.

The study included a description of fundamental reproducing kernel algorithm and the concepts of convergence, and error behavior for the reproducing kernel algorithm solvers. Results obtained by the proposed algorithm are found to outperform in terms of accuracy, generality and applicability.

Developing analytical and numerical methods for the solutions of time-fractional partial differential equations is a very important task owing to their practical interest.

This study, for the first time, presents reproducing kernel algorithm for obtaining the numerical solutions of some certain classes of Robin time-fractional partial differential equations. An efficient construction is provided to obtain the numerical solutions for the equations, along with an existence proof of the exact solutions based upon the reproducing kernel theory.