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Flip chip on board (FCOB) solder joint reliability under thermal shock stress was investigated. With underfill materials, the solder joint lifetime was increased from 37 to 1,300/2,480 cycles depending on the particular underfill material used. Through the use of CSAM, SEM, dye penetration tests and cross sectioning, the reliability of a FCOB assembly under thermal shock stress was evaluated. Both dye penetration and SEM fracture analysis can be used to measure quantitatively the extent of crack propagation for assemblies without underfill. A new failure mechanism, PCB cracking was also observed and discussed.

In this study, we propose and develop an opensource groupware system called NetIsle. NetIsle is a general purpose groupware system for uniform open groups that integrate a number of tools for online collaboration to ensure fast information exchange and sharing, increase the productivity of working groups, and reduce maintenance and administration costs. The main technologies used for the construction of the system are peer‐to‐peer (P2P) and push, which are best fitted to those principles and beliefs we build our system upon.

Flip chip solder joint reliability under thermal shock stress was investigated both experimentally and by 2D finite element simulation. The results indicate that solder fatigue is the dominant failure mode and that delamination has obvious adverse effects on the solder joint lifetime. Different material/process combinations (underfill, flux, reflow atmospheres) were designed in order to understand the role of material/process factors on the solder joint lifetime and the results are discussed.

The lifetime of flip chip solder joints can be greatly increased by applying underfill encapsulation. This paper presents a case study where the thermal cycle lifetime was increased by more than 20 times, that is from ∼100 cycles to more than 2,000 cycles for a chip size of 5.6mm × 6.3mm. By combining electrical, acoustic and metallographic investigation, the degradation of the solder joints was monitored, some important factors relevant to solder joint reliability were analysed and discussed. Delamination was found not to be the dominant failure mode.

The objective of this chapter is to analyze China’s outward foreign direct investment (OFDI) to the European Union in environmental industries.

We combine a narrative approach with statistical analysis. We first review the policy background concerning China’s OFDI and environmental protection. Then, we provide statistics on China’s OFDI to the EU in environmental industries, using firm-level data from one of China’s major provinces: Jiangsu.

We find that the OFDI to the EU in environmental industries experienced a considerable growth in terms of number of investing firms and investment value. The OFDI in environmental industries to the EU was highly concentrated in a few countries, particularly Germany and Luxemburg, and a few industries, particularly new energy.

Using firm-level data from only one province may limit the generalizability of our findings. However, we believe the case of Jiangsu province sheds much light on the situation of entire China because Jiangsu is one of the most important Chinese provinces in terms of OFDI.

The detailed analysis of our Jiangsu’s OFDI in EU’s environmental industries in this chapter can help to inform the investment cooperation in environmental industries between China and EU in terms of both scope of investment partners and target industries.

This study is one of the first to provide a detailed summary statistics on China’s OFDI to the EU in environmental industries. Given China’s growing concerns regarding environmental protection and OFDI, we believe the question merits further analysis.

Legislative hearings are a relatively new way of encouraging citizen participation in administrative law making within China. The first such hearing in Liaoning Province (Dalian City) was held in April 2005. The purpose of this paper is to examine the detail of the hearing process and attempts to assess its effectiveness as a mechanism for engagement between citizen and the state.

The authors consider both the practicalities of running a public hearing and its influence on the legal regulations under scrutiny. More generally, and within the limits of one case study, we consider whether hearings have the potential to shift the balance of power away from the state and its officials towards a more inclusive form of decision‐making.

Legislative public hearings appear to offer the opportunity for public engagement. The out‐workings of these in practice, if the Dalian case study and secondary evidence from five other Chinese cities is typical, suggests practical limitations, some of which are bound up with the cultural origins of a paternalistic public sector in China and deference to authority.

This paper examines whether citizen participation has been influenced by the wider global reform process of new public management and modernisation, synonymous with developed countries and offers insight into a more inclusive form of decision making for other public services.

To construct a scientific and reasonable indicator system, it is necessary to design a set of standardized indicator primary selection and optimization inspection process. The purpose of this paper is to provide theoretical guidance and reference standards for the indicator system design process, laying a solid foundation for the application of the indicator system, by systematically exploring the expert evaluation method to optimize the index system to enhance its credibility and reliability, to improve its resolution and accuracy and reduce its objectivity and randomness.

The paper is based on system theory and statistics, and it designs the main line of “relevant theoretical analysis – identification of indicators – expert assignment and quality inspection” to achieve the design and optimization of the indicator system. First, the theoretical basis analysis, relevant factor analysis and physical process description are used to clarify the comprehensive evaluation problem and the correlation mechanism. Second, the system structure analysis, hierarchical decomposition and indicator set identification are used to complete the initial establishment of the indicator system. Third, based on expert assignment method, such as Delphi assignments, statistical analysis, t-test and non-parametric test are used to complete the expert assignment quality diagnosis of a single index, the reliability and validity test is used to perform single-index assignment correction and consistency test is used for KENDALL coordination coefficient and F-test multi-indicator expert assignment quality diagnosis.

Compared with the traditional index system construction method, the optimization process used in the study standardizes the process of index establishment, reduces subjectivity and randomness, and enhances objectivity and scientificity.

The innovation point and value of the paper are embodied in three aspects. First, the system design process of the combined indicator system, the multi-dimensional index screening and system optimization are carried out to ensure that the index system is scientific, reasonable and comprehensive. Second, the experts’ background is comprehensively evaluated. The objectivity and reliability of experts’ assignment are analyzed and improved on the basis of traditional methods. Third, aim at the quality of expert assignment, conduct t-test, non-parametric test of single index, and multi-optimal test of coordination and importance of multiple indicators, enhance experts the practicality of assignment and ensures the quality of expert assignment.

Following the hierarchy-of-effects model, this study aims to propose a two-step process framework to investigate social media post efficacy via attraction and likes.

The study analyzes 113,785 social media posts from 126 WeChat official accounts to explore how external (headline features and account type) and internal (content features and media type) features impact social media post attractions and likes, respectively.

The antecedents of post attraction differ from those of post likes. First, headline features (punctuation, length, sentiment and lexical density) and account type significantly influence social media post attraction. Second, content features (depth, tone, domain specificity, lexical density and readability) and media type affect social media post likes.

First, this study considers online user engagement as a two-step process regarding social media posts and explores different influencing factors. Second, the study constructs new variables (account type and domain specificity) in each stage of the two-step process model.

The purpose of this paper is to maraging 18Ni-300 steel fabricate by powder bed based selective laser melting (SLM) process. Microstructure and mechanical properties of the maraging steel part before and after heat treatment at a slow cooling rate were investigated.

The microstructure of the printed part was observed by optical microscopy and scanning electron microscopy. The phases were determined by X-ray diffraction. The surface roughness of the part was recorded by a profilometer. The tensile properties and microhardness of the parts before and after heat treatment were characterized by an electronic universal tensile testing machine and a Vickers hardness tester, respectively.

Maraging 18Ni-300 steel part comprised of the martensitic phase and a small fraction of austenite phase. After heat treatment, the volume fraction of austenite slightly increased. The surface roughness of the part was about 96 µm. The printed part was dense, but irregular pores were present. The yield strength, ultimate tensile strength (UTS), elongation and Young’s modulus of as-fabricated parts were 554.7 MPa, 1173.1 MPa, 10.9% and 128.9 GPa, respectively. The yield strength, UTS, elongation and Young’s modulus of as-treated parts were 2065 MPa, 2225 MPa, 4.2% and 142.5 GPa, respectively. The microhardness values of surface and cross-section of the as-fabricated part were 407.1 HV and 443.0 HV, respectively. After short-time heat treatment, the microhardness values of the surface and cross-section of the part were 542.7 HV and 567.3 HV, respectively. After long-time heat treatment, the microhardness values of the surface and cross-section of the part were 524.4 HV and 454.8 HV, respectively. The microhardness and tensile strength increased significantly with decreasing elongation due to the changes in phases and microstructure of the parts after heat treatment.

This work studied the effect of heat treatment at 550°C combined with a subsequent slow cooling rate on microstructure and mechanical properties of maraging 18Ni-300 steel obtained by the powder bed based SLM process.