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The purpose of this study is to fabricate high-aspect-ratio grooves with high surface quality by femtosecond laser (FS) to improve the machinability of silicon carbide (SiC) and optimize the process parameters in micromechanical applications.

Four contrast experiments are reported to characterize the FS laser grooving process for SiC with polarization direction, crystal orientation, multi-pass scanning and z layer feed, respectively. The effects of different experimental conditions on the groove characteristics, material removal rate (MRR), aspect ratio, heat affected zone (HAZ) and surface roughness Ra are analyzed.

The influence of increasing laser fluence and multi-scanning pass on the groove depth is greater than on the groove width. The MRR, aspect ratio, HAZ and Ra increased with the increase of laser fluence and multi-scanning pass. The direction of laser polarization affects the direction of hot electron injection but has little effect on the material characteristics. FS laser ablation is an isotropic process and there is no obvious change in different crystal orientations. The z-layer feed can significantly increase the groove width and depth and reduce HAZ and Ra. The maximum aspect ratio of 82.67% was fabricated.

The results contribute to the understanding of the removal mechanism and reduce the friction of the microfluidic device and improve the flowability in the FS laser ablation of SiC. This paper provides suggestions for the selection of suitable process parameters and provides a wider possibility for the application of micro-texture on SiC.

In the context of virtual brand communities (VBCs), based on self-determination theory and organizational binary learning (OBL) theory, this study investigates the direct and indirect effects of various dimensions of consumer participation (CP) on firm innovation performance (FIP) and the mediating role of OBL. By introducing the perspective of knowledge absorptive capacity (KAC), this study examines the moderating effect of KAC on the relationship between OBL and TIP.

In this study, 751 samples are collected from Chinese firms, and stratified adjusted regression analysis is used to conduct empirical tests.

Information provision or co-creation directly affects FIP; the latter is more significant than the former, while social interaction does not directly affect FIP. Exploitative or exploratory learning plays a mediating role in the relationship between information provision or co-creation and FIP. In contrast, exploratory learning plays a mediating role in the relationship between social interaction and FIP. KAC has a positive moderating effect on the relationship between exploitative learning or exploratory learning and FIP. When the firm has a low KAC, the improvement of FIP through exploratory learning is slight.

In VBCs, this study tries to divide the dimensions of CP. It also clarifies the mediating effect of OBL on CP and FIP. In addition, it explores the moderating effect of KAC on OBL and FIP. The conclusions of this study provide theoretical support and practical inspiration for firms to use VBCs to improve FIP.

This study aims to better understand the relationship between peer feedback in the context of online collaborative note-taking and how comments impacted student performance and understanding.

This one sample investigation was of graduate students participating in an academic writing class working collaboratively online. Data was gathered on student feedback during note-taking activity to test for its effects on student performance and understanding.

The use of peer comments in online note-taking was found to impact student quiz scores and academic writing skills positively. However, no significance was found between comments and the completeness of their notes taken, suggesting its limits to promote deeper understanding.

The level and detail about the comments made and how accurately they recall the important details from the video lectures is not known. The average number of comments made weekly by each group was also low.

Designers and teachers using online collaborative activities could benefit by understanding the nature in which peer comments can enhance student learning, bearing in mind the need for explicit guidance in how to comment and at what level of knowledge their comments should target.

Online collaboration, peer editing and commenting is widely used by educators and the public. A better understanding of how these elements operate might improve the quality of knowledge artefacts such as academic writing and research notes.

Existing literature focuses mainly on peer feedback on writing or other artefacts; this paper seeks to find out more about the impact of comments in particular on collaborative note-taking.

Past studies have mainly concentrated on the impact of stress and self-employment on physical health. However, little research has paid attention to firm-level determinants of entrepreneurs’ physical health. This study aims to investigate the relationship between performance variability and entrepreneurs’ physical health as well as the moderating effect of prior failure experience.

This study uses data drawn from 255 start-ups across the Bohai Economic Rim in China over a period of three years (2015–2017). The results are still robust after several robustness checks.

Results show that performance variability is positively related to the probability of entrepreneurs showing poor health. This confirms that performance variability has an adverse effect on entrepreneurs’ physical health. Moreover, this relationship is moderated by the prior failure experience of entrepreneurs.

First, entrepreneurs should gain more information about the firm’s daily operation to reduce the potential threat of performance variability. Second, it is imperative for entrepreneurs to build a stable relationship with their stakeholders to avoid the potential costs related to performance variability. Finally, entrepreneurs should take health consequences into consideration when making strategic decisions.

First, this paper contributes to the studies on the antecedents of entrepreneurs’ physical health by introducing a firm-level determinant (i.e. performance variability). The findings enhance the understanding of the association between entrepreneurs and new ventures. Second, this paper also enriches the extant literature on the outcomes of performance variability. Finally, this paper attempts to offer new insights into prior failure experience by establishing its moderating effect on the performance–health relationship.

With the continuous development of Internet technology, virtual brand communities (VBCs) have increasingly become essential fronts for enterprises and consumers to carry out professional communication and the leading platform for consumers and other consumers to engage in social and brand discussion. Meanwhile, numerous scholars began to pay attention to VBCs as their research topic. However, there is no systematic understanding of the existing literature on the VBCs research. Therefore, this study aims to provide a comprehensive and systematic review of VBCs research over the past twenty years.

Based on HistCite and CiteSpace software, descriptive statistics and bibliometric analysis were conducted in this study. Specifically, by adopting research cooperation network analysis, co-citation analysis of literature, cluster analysis and co-word analysis, the authors analyzed 1,157 articles on VBCs in the Web of Science database from 2000 to 2020.

This study summarizes the research of VBCs from three aspects. First, the general characteristics of VBCs literature are analyzed. Second, knowledge bases, research contents, theoretical foundations and theoretical contributions of VBCs are dug and integrated into a knowledge framework. Third, the evolution and trend of VBCs research topics are visualized and analyzed in two phases (from 2005 to 2012 and from 2013 to 2020).

This study describes the research status, knowledge structure and famous topics of VBCs research over the past twenty years. Further, the research topics for VBCs have maintained continuity in the last twenty years. Furthermore, the research topics have also been evolving with the development of network technology and changes in the external environment. These results also provide valuable clues about this field's future directions and practical implications.

This study explores the importance of application search engine (ASE) technology in the omni-channel strategy. For this purpose, this chapter firstly explains the concepts of the omni-channel and the search engines and the importance of them. Then, omni-channel in the framework of ASEs is discussed. Finally, recommendations for further researches are presented.

The new Silk Road provides cross-border-e-commerce firms with an opportunity to widen their markets. Under this circumstance, the preference recognition of countries and inventory allocation among overseas warehouses both become critical issues to solve. Three Chinese smartphone brands, including HTC, Huawei, and MI, are selected in this chapter for their relatively enormous sales. DHgate and AliExpress websites are chosen as platforms to analyze the sales for data availability. This chapter first depicts key features of the sales and then, based on which, divide countries into several groups according to their preference for phones by cluster analysis. Then, based on the results of cluster analysis, this chapter further models the inventory assignment among the seven major overseas warehouses that were built by AliExpress in 2015. The results show that the HTC seems to be pursuing the “high value with high price” strategy, while the other two companies seem to be pursuing a hybrid strategy of “low-price” strategy and “high value with low price” strategy. This chapter also provides an assignment pattern of inventory among the overseas warehouses based on the real data of sales and costs.

The paper aims to explore the role of talent management (TM) practices in shaping firm’s absorptive capacity (AC) in the host country. Based on the data from representatives of Chinese diaspora used in Russia, this study discusses the role of TM practices in developing firm’s AC through learning from diaspora.

To explore possible connections between both TM practices and AC and TM practices and attractiveness of a company for diaspora representatives (talent mobility), this study reports an exploratory study by using a set-theoretical analytic method, fuzzy set qualitative comparative analysis.

The findings state that retention and development practices significantly influence firm’s AC, which promotes attractiveness of Russia as of destination country for Chinese employees and of particular company with the corresponding TM system.

This study reveals the existing connection between diaspora talent attraction and knowledge assimilation and diaspora talent retention and knowledge transformation. Knowledge acquisition is influenced by talent retention and talent development with a mediation of knowledge sharing.

Hill equations have definite limitation in the design of multiple spacecraft formation flying in eccentric orbits. To solve the problem, the design method of spacecraft formation flying in a circular reference orbit based on Hill equation can be generalized and applied to spacecraft formation flying in eccentric orbits.

In this paper, T‐H equation is expressed as the explicit function form of reference orbit true anomaly, and the state transition matrix of relative motion of spacecraft formation flying in eccentric orbits is derived. According to the requirement that relative dynamics equation of spacecraft formation flying in eccentric orbits has periodicity solution, the paper theoretically gives the initial condition needed by the long‐term close‐distance spacecraft formation flying including the relationship between relative position and relative velocity. Without perturbation the spacecraft formation, which satisfies the initial periodicity restriction, can keep long‐term close‐distance flying without the need of active control.

Based on the theoretical analysis, some numerical simulations are carried out. The results demonstrate that each spacecraft in eccentric orbits can run in a periodic motion surrounding the center spacecraft under some conditions. And spacecraft formation reconfiguration is implementing according to missions.

Combined with the periodicity restriction primary condition a new method about spacecraft formation reconfiguration is put forward. The method given by this paper can be applied to eccentric orbits of arbitrary eccentricity, and provides theoretical reference for orbit design of spacecraft formation flying in eccentric orbits.

An extensive literature in econometrics focuses on finding the exact and approximate first and second moments of the least-squares estimator in the stable first-order linear autoregressive model with normally distributed errors. Recently, Kiviet and Phillips (2005) developed approximate moments for the linear autoregressive model with a unit root and normally distributed errors. An objective of this paper is to analyze moments of the estimator in the first-order autoregressive model with a unit root and nonnormal errors. In particular, we develop new analytical approximations for the first two moments in terms of model parameters and the distribution parameters. Through Monte Carlo simulations, we find that our approximate formula perform quite well across different distribution specifications in small samples. However, when the noise to signal ratio is huge, bias distortion can be quite substantial, and our approximations do not fare well.