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1 – 10 of 733J.H. Huang, J.Y. Pei, Y.Y. Qian and Y.H. Jiang
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…
Abstract
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.
Mian Wang and Yajing Feng
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…
Abstract
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.
J.H. Huang, Y.H. Jiang, Y.Y. Qian and Q.L. Wang
This paper presents a viscoelastic model for analysing the mechanical behaviour of SnPb solders which has been developed by combining grain boundary slip with…
Abstract
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.
Wenjing Li, Qi Wang, Yongshan Ma, Tianyi Jiang, Yanyan Zhu, Yuanyuan Shao, Cuizhen Sun and Junsen Wu
Self-organization has been regarded as a tool for the synthesis of well-defined organic nanostructures. Heterocyclic annulated perylene diimides are the subjects of…
Abstract
Purpose
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.
Design/methodology/approach
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.
Findings
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).
Originality/value
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.
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Han Shen, Chengyi Song, Mimi Li and Qian Jiang
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…
Abstract
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.
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J.H. Huang, W. Gao, Y.Y. Jian and Y.H. Jiang
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…
Abstract
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…
Abstract
Purpose
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.
Design/methodology/approach
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.
Findings
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.
Research limitations/implications
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.
Practical implications
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.
Social implications
Developing analytical and numerical methods for the solutions of time-fractional partial differential equations is a very important task owing to their practical interest.
Originality/value
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.
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The subject of the fractional calculus theory has gained considerable popularity and importance due to their attractive applications in widespread fields of physics and…
Abstract
Purpose
The subject of the fractional calculus theory has gained considerable popularity and importance due to their attractive applications in widespread fields of physics and engineering. The purpose of this paper is to present results on the numerical simulation for time-fractional partial differential equations arising in transonic multiphase flows, which are described by the Tricomi and the Keldysh equations of Robin functions types.
Design/methodology/approach
Those resulting mathematical models are solved by using the reproducing kernel method, which provide appropriate solutions in term of infinite series formula. Convergence analysis, error estimations and error bounds under some hypotheses, which provide the theoretical basis of the proposed method are also discussed.
Findings
The dynamical properties of these numerical solutions are discussed and the profiles of several representative numerical solutions are illustrated. Finally, the prospects of the gained results and the method are discussed through academic validations.
Originality/value
In this paper and for the first time: the authors presented results on the numerical simulation for classes of time-fractional PDEs such as those found in the transonic multiphase flows. The authors applied the reproducing kernel method systematically for the numerical solutions of time-fractional Tricomi and Keldysh equations subject to Robin functions types.
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The purpose of this paper is to examine the post-enactment status of China’s Labour Contract Law and Labour Dispute Mediation and Arbitration Law, focusing on the dramatic…
Abstract
Purpose
The purpose of this paper is to examine the post-enactment status of China’s Labour Contract Law and Labour Dispute Mediation and Arbitration Law, focusing on the dramatic rise in remuneration litigation amidst much criticism of weak or ineffective implementation of these laws.
Design/methodology/approach
This paper deploys both quantitative and qualitative analysis methods to investigate the features of remuneration litigation. Remuneration judgments by Beijing People’s Courts from 1 January 2014 to 31 December 2017 provide the primary empirical data. The intrinsic features of remuneration disputes are investigated to delineate subcategories of claims. Several judges were also interviewed to further explore the nature of remuneration disputes.
Findings
Four types of remuneration claims were identified: regular wage, minimum wage, overtime and others (including subsidies and welfare). Examination of these four types, especially how they are processed until concluded by court adjudication, provides a fuller picture of the post-enactment status of these laws and yields objective and rational findings. To explain the continuing steady rise in the volume of remuneration claims, as more workers have knowledge of their rights and access to the courts, this study identifies an increase in the number of factually complicated cases (e.g. overtime claims) and abmiguity in the relevant law, leaving some remuneration disputes difficult, if not impossible, to adjudicate. Conversely, the study also finds significant positive trends following these laws’ enactment, particularly a reduction in straightforward cases, such as disputes concerning non-payment of wages/minimum wages, on which the law is clear. It is evidently imperative to improve the clarity of the current laws through further legislation, as the most appropriate next step in China’s juridification process of developing its own rule of Labour Law.
Research limitations/implications
This study is purposely limited to examining remuneration litigation in Beijing’s courts from 2014 to 2017, which is representative of the national trend of dramatically rising remuneration disputes, and thus provides valuable insights. Future studies should cover a wider geographic territory and other categories of labour disputes to provide an even more comprehensive picture of the challenges and potential solutions.
Practical implications
By understanding the driving factors of rising labour remuneration disputes, the legislature, workers and employers can act accordingly to curb labour conflicts. The growing complexity and technicality of remuneration litigation indicates that the pressing need of labour juridification is to deploy a subtle, comprehensive method to improve legal clarity and judicial professionalism.
Originality/value
This study uniquely divides the types of remuneration litigation in Beijing, adopting methods and yielding findings absent from the prior literature. Both the progress and challenges in China’s rule of Labour Law process are reflected in this work, together with public policy and theoretical implications for further study.
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