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This paper aims to study passive control techniques for transonic flow over a backward-facing step (BFS) using square-lobed trailing edges. The study investigates the efficacy of upward and downward lobe patterns, different lobe widths and deflection angles on flow separation, aiming for a deeper understanding of the flow physics behind the passive flow control system.

Large Eddy Simulation and Reynolds-averaged Navier–Stokes were used to evaluate the results of the study. The research explores the impact of upward and downward patterns of lobes on flow separation through the effects of different lobe widths and deflection angles. Numerical methods are used to analyse the behaviour of transonic flow over BFS and compared it to existing experimental results.

The square-lobed trailing edges significantly enhance the reduction of mean reattachment length by up to 80%. At Ma = 0.8, the up-downward configuration demonstrates increased effectiveness in reducing the root mean square of pressure fluctuations at a proximity of 5-step height in the wake region, with a reduction of 50%, while the flat-downward configuration proves to be more efficient in reducing the root mean square of pressure fluctuations at a proximity of 1-step height in the near wake region, achieving a reduction of 71%. Furthermore, the study shows that the up-downward configuration triggers early spanwise velocity fluctuations, whereas the standalone flat-downward configuration displays less intense crosswise velocity fluctuations within the wake region.

The findings demonstrate the effectiveness of square-lobed trailing edges as passive control techniques, showing significant implications for improving efficiency, performance and safety of the design in aerospace and industrial systems.

This paper demonstrates that the square-lobed trailing edges are effective in reducing the mean reattachment length and pressure fluctuations in transonic conditions. The study evaluates the efficacy of different configurations, deflection angles and lobe widths on flow and provides insights into the flow physics of passive flow control systems.

Psychological ownership has been a topic of intense debate for several decades, especially in the digital era. In addition, as part of the digital public domain, virtual communities shape our digital lives. Unfortunately, few studies have examined the communication process in virtual communities from the perspective of psychological ownership. Moreover, information and organization are key aspects of virtual communities. This research aimed to explore the impact of psychological ownership on communication satisfaction from these two perspectives.

I collected 471 responses using a questionnaire. In terms of empirical methods, I developed a structural equation model (SEM) to examine the relationship between psychological ownership and communication satisfaction as well as the mechanism underlying this relationship – namely, information behavior. Specifically, I first examined the relationship between psychological ownership and information behavior. I then developed a comprehensive framework for the double-edged impact of psychological ownership in virtual communities on communication satisfaction.

I found that psychological ownership has a double-edged effect on communication satisfaction based on two types of information behavior in virtual communities. Specifically, organization-based psychological ownership (OPO) positively influences communication satisfaction through information exchange. In contrast, information-based psychological ownership (IPO) negatively impacts communication satisfaction through information-hiding.

The findings of this research demonstrate that psychological ownership has a double-edged effect on communication satisfaction. First, the findings of this study reveal the downsides of psychological ownership, which are not consistent with its beneficial role. Second, the negative effect of psychological ownership with regard to communication in virtual communities also helps explain communication failure in virtual communities. Finally, despite the downsides of psychological ownership in the context of a virtual community revealed by this study, this factor has an overall beneficial effect.

This study aims to investigate the morphing concepts able to manipulate the dynamics of the downstream unsteadiness in the separated shear layers and, in the wake, be able to modify the upstream shock–boundary layer interaction (SBLI) around an A320 morphing prototype to control these instabilities, with emphasis to the attenuation or even suppression of the transonic buffet. The modification of the aerodynamic performances according to a large parametric study carried out at Reynolds number of 4.5 × 10⁶, Mach number of 0.78 and various angles of attack in the range of (0, 2.4)° according to two morphing concepts (travelling waves and trailing edge vibration) are discussed, and the final benefits in aerodynamic performance increase are evaluated.

This article examines through high fidelity (Hi-Fi) numerical simulation the effects of the trailing edge (TE) actuation and of travelling waves along a specific area of the suction side starting from practically the most downstream position of the shock wave motion according to the buffet and extending up to nearly the TE. The present paper studies through spectral analysis the coherent structures development in the near wake and the comparison of the aerodynamic forces to the non-actuated case. Thus, the physical mechanisms of the morphing leading to the increase of the lift-to-drag ratio and the drag and noise sources reduction are identified.

This study investigates the influence of shear-layer and near-wake vortices on the SBLI around an A320 aerofoil and attenuation of the related instabilities thanks to novel morphing: travelling waves generated along the suction side and trailing-edge vibration. A drag reduction of 14% and a lift-to-drag increase in the order of 8% are obtained. The morphing has shown a lift increase in the range of (1.8, 2.5)% for angle of attack of 1.8° and 2.4°, where a significant lift increase of 7.7% is obtained for the angle of incidence of 0° with a drag reduction of 3.66% yielding an aerodynamic efficiency of 11.8%.

This paper presents results of morphing A320 aerofoil, with a chord of 70cm and subjected to two actuation kinds, original in the state of the art at M = 0.78 and Re = 4.5 million. These Hi-Fi simulations are rather rare; a majority of existing ones concern smaller dimensions. This study showed for the first time a modified buffet mode, displaying periodic high-lift “plateaus” interspersed by shorter lift-decrease intervals. Through trailing-edge vibration, this pattern is modified towards a sinusoidal-like buffet, with a considerable amplitude decrease. Lock-in of buffet frequency to the actuation is obtained, leading to this amplitude reduction and a drastic aerodynamic performance increase.

This paper aims to describe a proposal for an innovative method of normal shock wave–turbulent boundary layer interaction (SBLI) and shock-induced separation control.

The concept is based on the introduction of a tangentially moving wall upstream of the shock wave and in the interaction region. The SBLI control mechanism may be implemented as a closed belt floating on an air cushion, sliding over two cylinders and forming the outer skin of the suction side of the airfoil. The presented exploratory numerical study is conducted with SPARC solver (steady 2D RANS). The effect of the moving wall is presented for the NACA 0012 airfoil operating in transonic conditions.

To assess the accuracy of obtained solutions, validation of the computational model is demonstrated against the experimental data of Harris, Ladson & Hill and Mineck & Hartwich (NASA Langley). The comparison is conducted not only for the reference (impermeable) but also for the perforated (permeable) surface NACA 0012 airfoils. Subsequent numerical analysis of SBLI control by moving wall confirms that for the selected velocity ratios, the method is able to improve the shock-upstream boundary layer and counteract flow separation, significantly increasing the airfoil aerodynamic performance.

The moving wall concept as a means of normal shock wave–turbulent boundary layer interaction and shock-induced separation control has been investigated in detail for the first time. The study quantified the necessary operational requirements of such a system and practicable aerodynamic efficiency gains and simultaneously revealed the considerable potential of this promising idea, stimulating a new direction for future investigations regarding SBLI control.

The purpose of this study is to identify the causative factors of metro construction safety accidents, analyze the correlation between accidents and causative factors and assist in developing safety management strategies for improving safety performance in the context of the Chinese construction industry.

To achieve these objectives, 13 types and 48 causations were determined based on 274 construction safety accidents in China. Then, 204 cause-and-effect relationships among accidents and causations were identified based on data mining. Next, network theory was employed to develop and analyze the metro construction accident causation network (MCACN).

The topological characteristics of MCACN were obtained, it is both a small-world network and a scale-free network. Controlling critical causative factors can effectively control the occurrence of metro construction accidents. Degree centrality strategy is better than closeness centrality strategy and betweenness centrality strategy.

In practice, it is very difficult to quantitatively identify and determine the importance of different accidents and causative factors. The weights of nodes and edges are failed to be assigned when constructing MCACN.

This study provides a theoretical basis and feasible management reference for construction enterprises in China to control construction risks and reduce safety accidents. More safety resources should be allocated to control critical risks. It is recommended that safety managers implement degree centrality strategy when making safety-related decisions.

This paper establishes the MCACN model based on data mining and network theory, identifies the properties and clarifies the mechanism of metro construction accidents and causations.

1. Explore the important role of sole actual controller in the innovation decision of the firm and the different effects of the ownership of sole actual controller on innovation; 2. Explore whether the role played by sole actual controllers varies in different types of firms; 3. Explore the important role of cooperative culture in the internal governance of firms and whether sole actual controller firms feel a rejection effect on cooperative culture.

The authors collect data on Shanghai and Shenzhen A-share listed companies from 2011 to 2021 to analyze the role of the sole actual controller on innovation investment, as well as the moderating effect of cooperative culture in corporate annual reports using natural language processing.

The authors find that sole actual controllers promote corporate innovation investment and that concentrated equity inhibits corporate innovation investment, while dispersed equity concentration promotes it. In addition, cooperative culture has a nonlinear moderating effect on the relationship between SACs and innovation.

On the one hand, this study focuses chiefly on the decision-making behavior of top managers, such as the SACs and shareholders, and does not account for the role of bottom-level employees or professional R&D teams in innovation. On the other hand, although this study discusses the moderating role of corporate cooperative culture, it is limited to internal cooperative culture; cooperative culture should also consider external cooperation, such as cooperation between companies or between companies and universities.

First, companies should actively implement the SAC model and scientifically select a truly compassionate and visionary SAC as the dominant person in the company. Second, the Chinese government needs to standardize the identification of actual controllers, who should not be a shareholder of the company. Third, policymakers should promote the reform of the mixed system of enterprises, optimize the shareholding structure of firms, make executives an important part of corporate governance. Fourth, cooperation culture is a good start, though firms should avoid letting it become a “double-edged sword” of the management mode of the SAC.

First, existing studies do not address the impact of SACs on innovation from the perspective of SACs, who have most influence the firm's decision-making. Focusing on the SAC's decision-making style has sufficient practical implications for future corporate innovation planning. This study used the natural language processing (NLP) module in ChatGPT to analyze the culture of cooperation in corporate annual reports. Currently, corporate culture is an obstacle to the study of corporate governance because of its obscurity and difficulty of quantification. The authors adopted a PSM (propensity score matching) approach to eliminate the endogeneity of the data, which makes the results more scientific.

The purpose of this paper is to consider one test of a well-functioning housing system – its impact on wellbeing. Exploring one indicator of this, this study aims to track changes in mental and general health across a mix of tenure transitions and financial transactions in three jurisdictions: Australia, the UK and the USA.

Using matched variables from three national panel surveys (Household, Income and Labour Dynamics in Australia, British Household Panel Survey/Understanding Society and Panel Study of Income Dynamics) over 17 years (2000–2017) to capture the sweep of the most recent housing cycle, this study adopts a difference-in-difference random-effects model specification to estimate the mental and general health effects of tenure change and borrowing behaviours.

There is an enduring health premium associated with unmortgaged owner-occupation. Mortgage debt detracts from this, as does the prospect of dropping out of ownership and into renting. A previously observed post-exit recovery in mental health – a debt-relief effect – is not present in the longer run. In fact, in some circumstances, both mental and general health deficits are amplified, even among those who eventually regain homeownership. Though there are cross-country differences, the similarities across these financialised housing systems are more striking.

The well-being premium traditionally associated with owner occupation is under threat at the edges of the sector in all three jurisdictions. In this, there is cross-national convergence. There may therefore be scope to introduce policies to better support households at the edges of ownership that work across the board for debt-funded ownership-centred housing systems.

This paper extends the duration of a previous analysis of the impact of tenure transitions and financial transactions on well-being at the edges of ownership in the UK and Australia. The authors now track households over nearly two decades from the start of the millennium into a lengthy (post-global financial crisis) era of declining housing affordability. This study adds to the reach of the earlier study by adding a general health variable and a third jurisdiction, the USA.

Based on the Cognitive Appraisal Theory of Stress, this study aims to reveal the mechanism of peer abusive supervision on bystander proactive behavior through two different paths: bystander assertive impression management motivation and bystander defensive impression management motivation. Besides, the moderating effects of bystander uncertainty tolerance on the two paths are also explored.

In this study, 438 employees and their direct leaders from eight Chinese companies were surveyed in a paired survey at three time points, and the empirical data was analyzed using Mplus 7.4 software.

Peer abusive supervision leads bystanders to develop assertive impression management motivation and, thus, to exhibit more proactive behaviors. At the same time, peer abusive supervision also causes bystanders to develop defensive impression management motivation, which reduces the frequency of performing proactive behaviors. In addition, this study finds that bystander uncertainty tolerance plays a moderating role in influencing bystander assertive impression management motivation and bystander defensive impression management motivation in response to peer abusive supervision.

Starting from the bystander perspective, this study verifies the double-edged sword effect of peer abusive supervision on bystander proactive behavior as well as the mechanism of differentiated effects through cognitive appraisal, which broadens the scope of the research on abusive supervision, and deepens the academic understanding and development of the Cognitive Appraisal Theory of Stress. At the same time, it also provides new ideas for organizations to reduce the negative effects of workplace abusive behavior.

This study aims to investigate the fit of a promotion (prevention) focus with malicious (benign) envy and how this fit influences positive and negative behaviours, depending on the context.

Four empirical studies (two laboratory and two online experiments) were used to test key hypotheses. Study 1 manipulated regulatory focus and envy in a job application setting with university students. Study 2 engaged similar manipulations in a social media setting. Studies 3 and 4 extended the regulatory focus and envy manipulations to the general population in pay-what-you-want (PWYW) and pay-it-forward (PIF) restaurant contexts.

The findings showed that a promotion (prevention) focus fits with the emotion of malicious (benign) envy. In the social media context, promotion and prevention foci demonstrated negative behaviour, including unfollowing the envied person, when combined with malicious and benign envy. In the PWYW and PIF contexts, combining envy with a specific type of regulatory focus encouraged both positive and negative behaviours through influencing payments.

Future research could validate and extend this study’s findings with different product/service categories, cross-cultural samples and research methods such as field experiments.

The four studies’ findings will assist managers in formulating marketing strategies to enhance their positioning of target products/services, possibly leading to higher prices for PWYW and PIF businesses.

The conceptual model is novel as, to the best of the authors’ knowledge, no prior research has proposed and tested the fit between envy type and regulatory foci.

Given that women around the world face more exclusion in terms of limited access to economic and innovation activities than men do, it is understandable that some female-led start-ups in weak institutional environments engage in bribery to help reduce the difficulties they encounter in the face of intense business competition. However, the link between bribery and product innovation performance is unclear. The purpose of this study is to investigate the relationship between bribery and product innovation performance for female-led start-ups, as well as the roles of institutional support and self-control in this link.

This empirical study evaluates survey data from female-led manufacturing start-ups in China's Yangtze River Delta region to investigate the relationship between bribery and product innovation performance.

This research shows that bribery has an inverted U-shaped impact on product innovation performance in female-led manufacturing start-ups, meaning that the product innovation performance of these firms initially increases but then decreases as the bribery intensity (i.e. the frequency and amount of bribes) increases. The authors also focus on the roles of institutional support and self-control in this link, where the authors find that this relationship is steeper for firms with strong institutional support, as well as for individual female entrepreneurs who have high levels of self-control.

The findings of this study indicate that policymakers should undertake efforts to improve institutional quality (e.g. increasing clarity around decisions, providing more institutional support, etc.) and to guide female entrepreneurs to cultivate higher levels of self-control, as such efforts would reduce the appeal of, and the opportunity for, bribery.

To date, very few studies focus specifically on female-led enterprises in the field of bribery research. The research findings presented here on the effect of bribery in female-led start-ups on firm product innovation performance are useful to researchers, policymakers and businesspeople, as they provide a better understanding of bribery in female-led start-ups in China, which can also be extrapolated to encompass other transition economy contexts.