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The purpose of this paper is to investigate the laser soldering of fine pitch quad flat package (QFP) devices using lead‐free solders and solder joint reliability during thermal cycling.

QFP devices were selected as the test vehicles and were soldered with four alloy types, Sn37Pb, Sn3.5Ag, Sn3.8Ag0.7Cu and Sn3.8Ag0.7Cu0.03Ce. The experimental samples were QFP‐256 devices with lead‐free solder paste on the printed circuit boards. The packages were dried for 24 h at 125°C prior to reflow soldering. Soldering experiments on the QFP devices were carried out with an infrared (IR) reflow soldering oven and a diode laser (DL) soldering system. Reflow soldering was performed at peak temperatures of 210°C (SnPb), 240°C (SnAgCu and SnAgCuCe) and 250°C (SnAg), as determined on the boards. Pull testing was adopted to evaluate the tensile strength of the four solders using an STR–1000 micro‐joint strength tester.

The tensile force of the QFP micro‐joints increased as laser intensity increased when it was less than an “optimal” value. The maximum tensile force of the QFP micro‐joints was gained when the laser intensity had increased to 2,165, 2,127, 2,165 and 2,064 W/cm², depending on the alloy used. The thermal fatigue performance of three lead‐free solder joints, SnAgCuCe, SnAgCu and SnAg, was determined to be superior to that of the eutectic SnPb alloy. After soldering without thermal cycling tests, the fracture morphology of soldered joints exhibited characteristic toughness fracture with both of the soldering methods. After 700 thermal cycles, the fracture mechanism was also toughness fracture, nevertheless, the dimples became large. The fracture morphology of the soldered joints subjected to 1,500 thermal cycles indicated brittle intergranular fracture on the fracture surface and no intense plastic deformation appeared before fracture with IR soldering. For DL soldering, the pull fracture model of the SnAgCuCe was completely ductile in the soldered joint with 1,500 thermal cycles.

The paper usefully investigates the influence of laser intensity on the tensile strength of different soldered joints and the solder joint reliability during thermal cycling.

The purpose of this paper is to investigate the impact of factor-based trading strategies on pricing and volume.

The authors employ a regression discontinuity approach to identify abnormalities in volume or pricing around expected portfolio changes. In addition, the authors characterize more granular effects on pricing and volume as a result of portfolio re-classification through Fama and Macbeth (1973) regressions.

The authors find that firms which are predicted to transfer among the factor portfolios of Fama and French (1993) exhibit strong and statistically significant short-term variation in stock price and volume. Short-term returns around the cutoff values comprising SMB and HML tend to be temporarily high if the firm is predicted to move into a long component of a factor-mimicking portfolio, and temporarily low if moving into a short component. Similar results are apparent when examining movement in and out of the 25 size and book-to-market sorted test asset portfolios.

The use of portfolio strategies formulated on the basis of sorting procedures, while once upon a time a niche market in the portfolio management industry, is now ubiquitous. The results of this study raise interesting methodological questions about the pricing implications arising from these common methodologies.

This study makes a number of contributions. First, it contributes to the idea that the publication or dissemination of trading strategies or – more generally – common portfolio sorting methods, leads to effects on pricing and volume through commonly motivated trading pressure. In other words, recipe-like discoveries of advantageous trading strategies lead to a synthetic creation of demand. Second, by noting that a lot of factor-focused trading activity begins around July and August of each year, the study relates to existing literature which documents seasonal variation in stock returns and volume. The findings raise questions about what guides institutional investors’ portfolio allocation decisions and whether these are optimal in aggregate.

The current paper extends previous studies on the match between CEO and firm and explores whether certain characteristics of young CEOs make them more desirable to young firms. Results in this paper will provide useful information to startup companies when they need to find managers leading the firms.

This study use a large sample of panel regression to study the match between CEOs and firm via a difference-in-differences approach.

The author finds that young firms hire a disproportionately higher percentage of young CEOs than established firms. Young firms led by young CEOs exhibit higher growth rates in sales and assets and invest more in capital expenditure and R&D activities than similar firms led by older CEOs. Young CEOs in young firms also receive higher compensation than both older CEOs working in young firms and young CEOs working in established firms.

There are many studies examining how CEO age affect their decision-making process. There are also many studies examining the differences between young firms and established firms. However, there is no study so far examining the intersection of the two questions above. Specifically, whether the differences between young vs established firms make certain characteristics of young CEOs beneficial to young firms.

Since China initiated its “go global” policy that promotes its overseas investment, China’s Outward Foreign Direct Investment (OFDI) has increased almost twenty times during the last 10 years, reaching $55.9 billion in 2008. The issue of internationalization of Chinese OFDI has attracted increasing attention of researchers from a business perspective. This article systematically reviews the previous studies on overseas investments by Chinese MNEs and discusses the characteristics of Chinese internationalization behavior at both firm level and country level. The internationalization of Chinese companies cannot be understood as a simple game of “catch up” with established MNEs, and more firm‐level empirical studies should be carried out on how these characteristics influence firms’ strategic decisions.

The purpose of this paper is to examine practicing mathematics teachers’ learning through parallel lesson study in China. Lesson study in China has been practiced for decades. Parallel lesson is an enriched mode of lesson study to address the implementation of new curriculum.

The expansive learning perspective has been used to explore the ways practicing teachers learned to improve teaching through the transformation of learning objects and boundary crossing.

Two cases are illustrated and compared to highlight features of teachers’ learning through parallel lesson study. The practicing teachers developed their competence in transforming instructional objectives and task selection and implementation. In addition, they also developed professional vision in alignment with the reform-oriented curriculum.

This study makes significant contribution to understanding teachers’ learning through lesson study in China. Meanwhile, it also demonstrates how the theory of expansive learning could be used as a conceptual framework to examine teachers’ learning through lesson study.

In today’s digital era, talent recruitment can help address the growing shortage of skilled labor in the construction industry and promote sustainable growth. While existing research has explored the association between talent acquisition and local labor productivity or economic progress, the impact on construction growth deserves further study. This study aims to (1) explore the influence of talent recruitment on the growth of the construction industry and (2) analyze whether different regional characteristics shape the differential impact of talent acquisition on construction growth.

This research employs a quantitative approach, focusing on 35 major cities in China. A panel data regression model is utilized to analyze annual data from 2013 to 2018, considering variables like the construction talent recruitment index, value added in construction, gross regional product per capita and others. The study also examines regional heterogeneity and conducts robustness tests to validate the findings.

The results reveal a positive and significant correlation between talent recruitment and construction industry growth. This correlation is more pronounced in economically advanced and infrastructure-rich regions. The study also finds that factors like capital investment, educational attainment and housing prices significantly contribute to industry growth. Talent recruitment not only transforms local labor market dynamics but also drives demand for construction services, promoting industry growth through economies of scale.

This research constructs a new measurement for talent recruitment and provides new insights into the pivotal role of talent recruitment in the sustainable growth of the construction industry. It underscores the need for construction firms to tailor talent acquisition policies to their specific circumstances and regional developmental conditions. The findings offer practical guidance for driving regional growth within the sector, emphasizing the importance of talent recruitment as a key yet previously underappreciated factor in industry development.

Mainland Chinese firms have become important international investors. Many have gained their capabilities to internationalize in a domestic institutional environment characterised by significant market imperfections. In this study, we argue that the imperfections affect firm behavior depending on firm size, ownership form, and location. We find preliminary support for the notion that large, well connected Chinese firms benefit most from institutional advantages, but that smaller firms internationalize because of institutional constraints. This represents a more nuanced view of the determinants of Chinese firm internationalization than is evident in prior research, with consequences for future theorising and empirical research on Chinese MNEs.

This article aims to describe and discuss four major innovations to improve the quality of teacher education including preparation programs and professional development programs in recent years in China. The four major innovations include establishing the National Curriculum Standards for Teacher Education (NCSTE) and the National Teacher Certification Examination; implementing the “double development plan” to reform clinical practice; launching the “National Training Plan” to develop in‐service teachers; and consolidating the career ladder for teachers.

The paper takes the form of a review of the government documents and current literature.

The author argues that the four major innovations reflect the central trends to reform teacher education both in China and the USA – increased standards and accreditation, more clinical experiences in preparation, increased use of technology in teacher professional development, and more accountability and incentive for teachers.

When the world is faced with the globalized economy, cultural exchange and social equity issues, discussions about the recent innovations of China's teacher education will shed light on our understanding of better approaches to improve teacher quality that no doubt connect tradition and local practices with global convergence.

In developed markets, emerging market multinational enterprises (EMNEs) seem to be more discriminated by host country nationals than foreign developed market multinational enterprises (DMNEs). They are challenged with host country nationals’ prejudices and face a stigma of being from emerging markets. While literature agrees that EMNEs suffer from additional disadvantages due to their country-of-origin, research fails to identify those factors that may lead to a higher discrimination against EMNEs than against foreign DMNEs.

Based on institutional theory, we look at institutional-related and resource-related antecedents that have an impact on various forms of direct and indirect discrimination by host country nationals.

Our framework analyzes the crucial differences between host country nationals’ perception of EMNEs and foreign DMNEs and the resulting challenges for EMNEs in the developed world. It enhances our understanding of the importance of institutional environments in explaining differences in host country nationals’ discrimination against foreign MNEs.