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Higher energy conversion efficiency of internal combustion engine can be achieved with optimal control of unsteady in-cylinder flow fields inside a direct-injection (DI) engine. However, it remains a daunting task to predict the nonlinear and transient in-cylinder flow motion because they are highly complex which change both in space and time. Recently, machine learning methods have demonstrated great promises to infer relatively simple temporal flow field development. This paper aims to feature a physics-guided machine learning approach to realize high accuracy and generalization prediction for complex swirl-induced flow field motions.

To achieve high-fidelity time-series prediction of unsteady engine flow fields, this work features an automated machine learning framework with the following objectives: (1) The spatiotemporal physical constraint of the flow field structure is transferred to machine learning structure. (2) The ML inputs and targets are efficiently designed that ensure high model convergence with limited sets of experiments. (3) The prediction results are optimized by ensemble learning mechanism within the automated machine learning framework.

The proposed data-driven framework is proven effective in different time periods and different extent of unsteadiness of the flow dynamics, and the predicted flow fields are highly similar to the target field under various complex flow patterns. Among the described framework designs, the utilization of spatial flow field structure is the featured improvement to the time-series flow field prediction process.

The proposed flow field prediction framework could be generalized to different crank angle periods, cycles and swirl ratio conditions, which could greatly promote real-time flow control and reduce experiments on in-cylinder flow field measurement and diagnostics.

This study examines the impact of China’s mixed-ownership reform on the innovation of non-state-owned acquirers, with a particular focus on the impact on firms with high financing constraints, low-quality accounting information or less tangible assets.

We use a proprietary dataset of firms listed on the Shanghai and Shenzhen Stock Exchanges to investigate the impact of mixed ownership reform on non-state-owned enterprise (non-SOE) innovation. We employ regression analysis to examine the association between mixed ownership reform and firm innovation.

The study finds that non-state-owned firms can improve innovation by acquiring equity in state-owned enterprises (SOEs) under the reform. Eased financing constraints, lowered financing costs, better access to tax incentives or government subsidies, lowered agency costs, better accounting information quality and more credit loans are underlying the impact. Additionally, cross-ownership connections amongst non-SOE executives and government intervention strengthen the impact, whilst regional marketisation weakens it.

This study adds to the literature on the association between mixed ownership reform and firm innovation by focussing on the conditions under which this impact is stronger. It also sheds light on the policy implications for SOE reforms in emerging economies.

The aim of this research, which uses the theories of social identity and social exchange, is to investigate the relationship between responsible leadership, prosocial behavior and the mediating role of psychological ownership in this relationship. In addition, the moderating role of ethical and social responsibility in the relationship between responsible leadership and psychological ownership is tested in the study.

The sample of the research consists of 246 participants who work full-time at İstanbul Sabiha Gökçen Airport in ground handling services (GHS). The convenience sampling method was used in the research, and the research data were collected by the face-to-face survey method. The hypotheses of the research were tested with the partial least squares structural equation model (PLS-SEM) and SPSS Process Macro.

According to the results, it was determined that responsible leadership affects prosocial behavior positively and significantly, and psychological ownership plays a mediating role in this relationship. In addition, the moderating effect of ethical and social responsibility on the relationship between responsible leadership and psychological ownership was determined. When ethical and social responsibility is perceived as high by the employees, it was revealed that the conditional indirect effect of responsible leadership on prosocial behavior through psychological ownership was strong.

When responsible leadership encourages employees to take psychological ownership, they are more likely to engage in prosocial behavior. This study contributes to the field by evaluating the structures discussed with social identity and social exchange theory. In the management practice of organizations, responsible leadership should be strengthened and training should be given to develop responsible leadership.

In the literature review, it was observed that although there are studies conducted with responsible leadership, the concept was not examined with prosocial behavior, and it was not studied in the aviation sector, which has become indispensable for the world economy. With these features, the study distinguishes itself from others and constitutes a source of motivation for researchers.

The purpose of this paper is to add expanded perlite (EP) immobilized microorganisms that replace part of the standard sand in mortar to improve the self-healing ability of mortar cracks and reduce the water absorption of mortar after healing.

Bacillus pseudofirmus spores were immobilized with EP particles as self-healing agents. The effects of adding self-healing agents on the compressive strength of mortar specimens were observed. The ability of mortar specimens to heal cracks was evaluated using crack microscopic observation and water absorption experiments. The filler at the cracks was microscopically analyzed by scanning electron microscope and X-ray diffraction experiments.

First, the internal curing effect of EP promotes the hydration of cement in mortar, which generates more amount and denser crystal structure of Ca(OH)2 at mortar cracks and improves the self-healing ability of mortar. Second, the self-healing ability of mortar improves with the increase of self-healing agent admixture. Adding a self-healing agent of high admixture makes the planar undulation of calcite crystal accumulation at mortar cracks more significant. Finally, the initial crack widths that can be completely healed by adding EP and self-healing agents to the mortar are 200 µm and 600 µm, respectively.

The innovation points of this study are as follows. (1) The mechanism of the internal curing effect of EP particles on the self-healing ability of mortar cracks was revealed by crack microscopic observation tests and microscopic experiments. (2) The effect of different self-healing agent amounts on the self-healing ability of mortar cracks has been studied. (3) The effects of EP particles and self-healing agents on healing different initial widths were elucidated by crack microscopic observation tests.

This paper aims to prepare third-order nonlinear optical (NLO) organic materials with large nonlinear optimization value, high damage threshold and ultrafast response time.

A series of novel symmetric and asymmetric compounds possessing third-order NLO properties were synthesized using 1,3,5-tribromobenzene as the basis. The photophysical and electrochemical properties, as well as the click reactions, were characterized by means of UV–VIS–NIR absorption spectroscopy and cyclic voltammetry.

The donor–acceptor chromophores were inserted into compound, making the molecule to have a broader absorption in the near-infrared regions and a narrower optical and electrochemical band gap. It also formed an electron-delocalized organic system, which has larger effects on achieving a third-order NLO response. The third-order NLO phenomenon of benzene ring complexes was experimentally studied at 532 nm using Z-scan technology, and some compounds showed the expected NLO properties.

The click products exhibit more NLO phenomena by performing different click combinations to the side groups, opening new perspectives on using the system in a variety of photoelectric applications.

Extant research shows mixed results on the impact of expressed negative emotions on donations in online charitable crowdfunding. This study solves the puzzle by examining how different types of negative emotions (i.e. sadness, anxiety and fear) expressed in crowdfunding project descriptions affect donations.

Data on 15,653 projects across four categories (medical assistance, education assistance, disaster assistance and poverty assistance) from September 2013 to May 2019 come from a leading online crowdfunding platform in China. Text analysis and regression models serve to test the hypotheses.

In the medical assistance category, the expression of sadness has an inverted U-shaped effect on donations, while the expression of anxiety has a negative effect. An appropriate number of sadness words is helpful but should not exceed five times. In the education assistance and disaster assistance categories, the expression of sadness has a positive effect on donations, but disclosure of anxiety and fear has no influence on donations. Expressions of sadness, anxiety and fear have no impact on donations in the poverty assistance category.

This work has important implications for fundraisers on how to regulate the fundraisers' expressions of negative emotions in a project's description to attract donations. These insights are also relevant for online crowdfunding platforms.

Online crowdfunding research often studies negative emotions as a whole and does not differentiate project types. The current work contributes by empirically testing the impact of three types of negative emotions on donations across four major online crowdfunding categories.

This study collected the bibliographic data of 2034 journal articles published in 2000–2021 from Web of Science (WoS) core collection database and adopted two bibliometric analysis methods, namely historiography and keyword co-occurrence, to identify the evolution trend of construction risk management (CRM) research topics.

CRM has been a key issue in construction management research, producing a big number of publications. This study aims to undertake a review of the global CRM research published from 2000 to 2021 and identify the evolution of the research topics relating to CRM.

This study found that risk analysis methods have shifted from simply ranking risks in terms of their relative importance or significance toward examining the interrelationships among risks, and that the objects of CRM research have shifted from generic construction projects toward specified types of construction projects (e.g. small projects, underground construction projects, green buildings and prefabricated projects). In addition, researchers tend to pay more attention to an individual risk category (e.g. political risk, safety risk and social risk) and integrate CRM into cost, time, quality, safety and environment management functions with the increasing adoption of various information and communication technologies.

This study focused on the journal articles in English in WoS core collection database only, thus excluding the publications in other languages, not indexed by WoS and conference proceedings. In addition, the historiography focused on the top documents in terms of document strength and thus ignored the role of the documents whose strengths were a little lower than the threshold.

This review study is more inclusive than any prior reviews on CRM and overcomes the drawbacks of mere reliance on either bibliometric analysis results or subjective opinions. Revealing the evolution process of the CRM knowledge domain, this study provides an in-depth understanding of the CRM research and benefits industry practitioners and researchers.

The purpose of this study is to determine the dimensions of cultural differences, which are theoretically most relevant to contract functions in international marketing. Moreover, the contradiction between contract governance and opportunism is reconciled by exploring the boundary conditions of specific cultural differences.

The authors obtained 235 bilateral data provided by Chinese exporters and overseas distributors. The authors matched a secondary data set with the questionnaire data, which were analyzed by confirmatory factor analysis and a hierarchical moderation model.

The results demonstrate that while contract specificity is less successful in this area, contingency adaptability is useful in reducing opportunism. Moreover, as the national cultural differences regarding uncertainty avoidance, power distance or individualism-collectivism become more pronounced. One contractual dimension will be more effective at curbing opportunism, while the other will be less effective.

Despite sample limitations, to the best of the authors’ knowledge, this paper is the first to theoretically identify the effect of cultural difference dimensions in contract governance, unlike past studies taking cultural differences as an aggregated variable. Furthermore, by exploring the boundary conditions of cultural differences, this paper effectively reconciles the conflicting findings on the relationship between contract governance and opportunism in various cultural context.

Exporters’ managers can design contingency adaptability to complement the limitations of contract specificity and consider cultural differences’ contingency effects.

First, the authors identify cultural differences dimensions related to contract governance, refining and emphasizing the research context. Second, comparing the efficacy of contract specificity and contingency adaptability in specific cultural context can show which contract is better at preventing opportunism.

This study aims to propose a research model that emphasizes the moderating influence of ethical leadership (ELS) and the link between socially responsible human resource management (SRHRM) and leaders’ eco-helping behavior (LEH) in the aviation industry.

The authors used a time-lag research design. Data were gathered from 397 respondents working for aviation companies in Vietnam and analyzed using SmartPLS 4.0.

The findings show that SRHRM has a beneficial effect on LEH through employees’ voluntary workplace green behavior (EVB). Based on social cognitive theory, this study developed a theoretical model of how SRHRM influences LEH through EVB. The authors discovered that SRHRM increased LEH and that EVB mediated this favorable relationship. Furthermore, the results demonstrate that ELS mitigates the indirect impact of SRHRM on LEH via EVB.

Future studies should assess constructs with numerous observations across time, with a larger sample size and in different industrial settings.

Volunteerism is one of the most important values in the aviation industry given that it is vulnerable to practices such as overbooking, delaying, postponing flights and pressure weather.

This study emphasized the impact of SRHRM and ELS on LEH while fulfilling their professional obligations. EVB may be best positioned to mediate the relationship between SRHRM and LEH.

Building supply chain resilience is increasingly recognized as an effective strategy to deal with supply chain challenges, risks and disruptions. Nevertheless, it remains unclear how to build supply chain resilience and whether supply chain resilience could achieve a competitive advantage.

By analyzing the data collected from 216 firms in China, the current study empirically examines how information technology (IT) capability and supply chain collaboration affect different forms of supply chain resilience (external resilience and internal resilience) and examines the performance implications of these two forms of supply chain resilience.

Results show that IT capability is positively related to external resilience, whereas supply chain collaboration is positively related to internal resilience. The combination of IT capability and supply chain collaboration is positively related to external resilience. In addition, internal resilience is positively related to firm performance.

This study used only cross-sectional data from China for hypothesis testing. Future studies could utilise longitudinal data and research other countries/regions.

The findings systematically assess how IT capability and supply chain collaboration contribute to supply chain resilience and firm performance. The results provide a benchmark of supply chain resilience improvement that can be expected from IT capability and supply chain collaboration.

The study findings advance the understanding of supply chain resilience and provide practical implications for supply chain managers.