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This paper aims to report a case study in flexible learning with multicomponent blended learning mode in an undergraduate chemistry course. Traditional chemistry courses usually include lectures, tutorials and laboratory sections. For a course “Advances in Organic Synthesis” at undergraduate level, it consists of advanced information in organic chemistry such as reaction mechanisms, asymmetric catalysis, retrosynthesis and applications in synthesis of natural products. This course is a difficult subject and requires deep understanding of contents. After learning this course, students should have comprehensive knowledge in advanced strategies of organic synthesis and have an ability to apply them to real cases. This “flexible learning with multicomponent blended learning mode” was implemented by the authors to enhance student engagement and self-motivation in their studies.

The authors hoped to enhance students’ engagement in “flexible learning” – a mixed concept with “blended learning” and “flipped classroom” – and called this approach as “multicomponent blended learning mode.” Blended learning combines face-to-face and e-learning components with interactive Web-based components and technical experimental videos were developed. The knowledge integrated in different components provides a natural environment to link the different synthetic methods together, which help students to get a better understanding of the complicated knowledge and strengthen their skills. For flipped classroom, students participated in the case studies of the organic synthesis and shared their findings to other classmates in oral presentations.

In this study, both course evaluation score and students’ academic performance in the “multicomponent blended learning mode” were increased significantly when comparing with traditional teaching methods in 2011. It was found that students’ engagement and their self-motivation in learning were enhanced.

The positive feedback from the students and the enhancement of their academic performance supported the value in this research. Besides, most universities in Hong Kong have suspended all face-to-face classes and conducted all teaching in online mode during COVID-19 outbreak. As the multicomponent blended learning mode of this course has already been conducted for eight cohorts, the authors are confident that this feature can minimize the sudden change in the learning habits for the students. As social factors and individual variations in students’ learning and study mode may affect the learning outcomes, these interactive multicomponent e-learning components in this special period make students excited when they can study and digest the knowledge according to their own pace.

This paper aims to investigate the influence of laser energy density on microstructure and mechanical properties of the selective laser melted (SLMed) Ti6Al4V to complement the existing knowledge in additive manufacturing of Ti6Al4V for future application of selective laser melting (SLM) in fabricating Ti6Al4V parts.

Ti6Al4V alloy is fabricated by SLM by adopting various energy densities. Microstructures and mechanical properties of the Ti6Al4V deposited using different energy densities are characterized.

Both high relative densities and microhardness can be obtained in the optimized processing window. The decrease of martensite width and spacing can improve the microhardness on both XOY and XOZ sections when the applied E_V (defined as the laser energy per unit volume) increases. The width of the columnar grain increases with E_V, resulting in a stronger anisotropy in microhardness between XOY and XOZ sections. Residual tensile stresses exist in the SLMed Ti6Al4V and increase with an increasing E_V. A tensile strength of 1,268 MPa, a yield strength of 1,030 MPa, and an elongation of 4% can be obtained by using the optimized range of E_V.

The microstructure of SLMed Ti6Al4V is quantitatively analysed by measuring the size of columnar grains and the martensites. The anisotropy of microstructures and properties in SLMed Ti6Al4V is characterized and its dependence on laser energy density is established. The residual stress in SLMed Ti6Al4V is characterized and its dependence on laser energy density is established. An optimized processing window to deposit Ti6Al4V alloy by SLM is proposed.

Cultural differences have been frequently cited as a major source of risks for international joint ventures (IJVs). Cultural differences may cause extensive conflicts in technology, norms and emotion among the international joint venture (IJV) partners. The purpose of this study is to explore the interactive effects of national culture differences (NCDs) and conflict management approaches on the performance of international construction joint ventures (ICJV).

Data were collected using a questionnaire survey method with 143 valid responses. Partial least squares structural equation modeling (PLS-SEM) was used to test the research hypotheses.

It was found that ICJV performance declined with a high degree of NCDs. The negative effect of NCDs on ICJV performance was mitigated by adopting the cooperative conflict management approach; while it was aggravated by adopting the competitive conflict management approach. The findings may provide an alternative way (i.e. adopting the cooperative conflict management approach rather than avoiding or competitive approaches) to address the cultural conflicts in the multicultural project management teams.

Firstly, as NCD negatively impacts performance of ICJVs, project managers should pay attention to cultural issues and learn how to manage them; Secondly, as cooperative and competitive conflict management approaches have different moderating effects on the relationship between NCD and ICJV performance, project managers must choose appropriate conflict management styles in multination teams. Thirdly, as the avoiding approach has no significant moderating effect on the negative relationship between NCD and ICJV performance, it is important for Chinese partners not to employ avoiding approach to deal with conflicts in ICJV.

This study uniquely adds to the literature on cultural issues in managing ICJVs by integrating the moderating effects of conflict management approaches. The interactive effects of conflict management approaches and national cultural differences on ICJV project performance may contribute to the theories regarding conflict management theory in the context of cross-cultural management.

The paper seeks to report data on cigarette smoking, anti‐smoking practices, physicians' receipt of anti‐smoking training, and the association between receipt of the training and anti‐smoking practice among physicians in Wuhan, China.

Participants were selected through the stratified random sampling method. The questionnaires were completed by the sampled physicians and the response rate of the survey was 98.1 percent.

Among the total sample, 11 percent were current smokers. Significantly more male physicians than female physicians were current smokers (31.6 vs 0.9 percent, p<0.001). In total, 41 percent of physicians always or often asked patients about smoking habits, and 61 percent of them often advised patients to quit. Receiving anti‐tobacco training significantly increased the likelihood for physicians to ask patients about smoking (odd ratio=2.55, p<0.001) and to advise patients against smoking (odd ratio=4.05, p<0.001) with and without controlling gender, age, education, type of hospital and medical services specialty.

More effort should be devoted to training for physicians with focus on anti‐smoking practice and smoking cessation counseling in addition to assist physicians themselves to quit smoking.

The findings of this study update the data regarding cigarette smoking among physicians in Wuhan, China, and their practice of anti‐tobacco counseling. It indicates that it is very important to provide the training regarding anti‐smoking counseling among physicians.

In the past few decades, the content-based image retrieval (CBIR), which focuses on the exploration of image feature extraction methods, has been widely investigated. The term of feature extraction is used in two cases: application-based feature expression and mathematical approaches for dimensionality reduction. Feature expression is a technique of describing the image color, texture and shape information with feature descriptors; thus, obtaining effective image features expression is the key to extracting high-level semantic information. However, most of the previous studies regarding image feature extraction and expression methods in the CBIR have not performed systematic research. This paper aims to introduce the basic image low-level feature expression techniques for color, texture and shape features that have been developed in recent years.

First, this review outlines the development process and expounds the principle of various image feature extraction methods, such as color, texture and shape feature expression. Second, some of the most commonly used image low-level expression algorithms are implemented, and the benefits and drawbacks are summarized. Third, the effectiveness of the global and local features in image retrieval, including some classical models and their illustrations provided by part of our experiment, are analyzed. Fourth, the sparse representation and similarity measurement methods are introduced, and the retrieval performance of statistical methods is evaluated and compared.

The core of this survey is to review the state of the image low-level expression methods and study the pros and cons of each method, their applicable occasions and certain implementation measures. This review notes that image peculiarities of single-feature descriptions may lead to unsatisfactory image retrieval capabilities, which have significant singularity and considerable limitations and challenges in the CBIR.

A comprehensive review of the latest developments in image retrieval using low-level feature expression techniques is provided in this paper. This review not only introduces the major approaches for image low-level feature expression but also supplies a pertinent reference for those engaging in research regarding image feature extraction.

The key purpose of conducting this review is to identify the issues that affect the structural integrity of pipeline structures. Heat affected zone (HAZ) has been identified as the weak zone in pipeline welds which is prone to have immature failures

In the present work, literature review is conducted on key issues related to the structural integrity of pipeline steel welds. Mechanical and microstructural transformations that take place during welding have been systematically reviewed in the present review paper.

Key findings of the present review underline the role of brittle microstructure phases, and hard secondary particles present in the matrix are responsible for intergranular and intragranular cracks.

The research limitations of the present review are new material characterization techniques that are not available in developing countries.

The practical limitations are new test methodologies and associated cost.

The fracture of pipelines significantly affects the surrounding ecology. The continuous spillage of oil pollutes the land and water of the surroundings.

The present review contains recent and past studies conducted on welded pipeline steel structures. The systematic analysis of studies conducted so far highlights various bottlenecks of the welding methods.

Stochastic computing which is an alternative method of the binary calculation has key merits such as fault-tolerant capability and low hardware cost. However, the hardware response time of it is required to be very fast due to its bit-wise calculation mode. While the complementary metal oxide semiconductor (CMOS) components are difficult to meet the requirements aforementioned. For this, the stochastic computing implementation scheme based on the memristive system is proposed to reduce the response time. The purpose of this paper is to provide the implementation scheme based memristive system for the stochastic computing.

The hardware structure of material logic based on the memristive system is realized according to the advantages of the memristor. After that, the scheme of NOT logic, AND logic and multiplexer are designed, which are the basic units of stochastic computing. Furthermore, a stochastic computing system based on memristive combinational logic is structured and its validity is verified successfully by operating a case.

The numbers of the elements of the proposed stochastic computing system are less than the conventional stochastic computing based on CMOS circuits.

The paper proposed a novel implementation scheme for stochastic computing based on the memristive systems, which are different from the conventional stochastic computing based on CMOS circuits.

This study aims to investigate the historical technological catch-up processes with particular attention to the role of windows of opportunity (WoO). As Industry 4.0 becomes the benchmark of many latecomer countries, this paper may provide guidelines to both policymakers and business practitioners. For clarifying how to catch up with the incumbents and leaders, the authors summarize the lessons based on the historical observations to conclude the pathways for latecomers who aim to reduce the gaps to leaders and manage catch-up. This study enriches the literature of catch-up from a holistic view with fresh insights into how and where to catch up.

The authors analyze the technological catch-up processes emerged in advanced industrial powers, newly industrialized countries (NICs) and emerging economies (EEs). By categorizing the countries into three kinds, they summarize the processes of catch-up along with the industry evolutions. Moreover, they explore how WoO may facilitate the catch-up processes from one stage to the next in above-mentioned categories. Doing so helps to further examine how technological catch-up and WoO interplay and differ among countries. Then, the authors further investigate the latecomers and incumbents and conclude the target choosing, path setting and direction selecting when implementing a catch-up strategy.

This study shows that technological catch-up emerged first in advanced industrial powers (AIPs), then in NICs and recently in EEs. Technological catch-up processes in AIPs and NICs take longer time than those in EEs. WoO from policy, market and technology usually collaboratively facilitate the technological catch-up processes in AIPs and NICs. However, in EEs, single WoO can lead to a successful catch-up. The authors further summarize the directions and pathways of catch-up: AIPs and NICs are normally considered by some latecomers to catch up with, while EEs are not.

This study is among the first to systematically review the historical developments of industry evolutions by focusing the technological catch-up based on the different categories of countries: AIPs, NICs and EEs. Moreover, the authors are also among the first few integrating the WoO and technological catch-up processes in different kinds of countries. To the best of the authors’ knowledge, they are also one of the pioneers who highlight the directions and pathways of latecomers and target choosing to catch up with. They also explore the possibility of selecting EEs as catch-up targets.

After three decades of development, the Chinese electric vehicle industry became the world’s largest electric vehicle market in 2015. However, little is understood about how the Chinese electric vehicle industry, as a latecomer in this strategic newly emerged industry, could catch up with international incumbents. The purpose of this paper is to study how the windows of opportunity emerge and interactively influence the catch-up process of Chinese electric vehicle industry.

This paper conducted a case study to examine how Chinese electric vehicle latecomers use the windows of opportunity along with the development of a sectoral system of innovation to reduce the gaps.

The results indicate that windows of opportunity appeared in the introduction stage (2005) and the transition from the introduction stage to the growth stage (2015) because of the sectoral changes in technologies, demand, policies and the interaction among these factors. Domestic electric vehicle latecomers currently follow the catch-up pattern of duplication, creative imitation and innovation.

To capture the previous windows of opportunity, domestic electric vehicle latecomers rely on technology transfer through international joint ventures, government support and local advantages from cheap labor. To seize future windows of opportunity, apart from progressively accumulating innovation capabilities, it is also essential for managers to recognize, break through and extend the windows of opportunity by anticipating and monitoring the process of changes of the sectoral system.

This paper provides a fine-grained study on how latecomers in a new industry with emerging markets can seize windows of opportunities to catch up with the international leaders.