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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.

Empowering leadership is often considered unequivocally positive for employees, but recent studies have shown that this ostensibly straightforward effect is more complex. The dual facets of the effect of empowering leadership – especially on employees’ innovative behaviour – have received insufficient attention. Based on job demand-resource (JD-R) theory, this study aims to propose a theoretical framework for the relationship between empowering leadership and employees’ innovative behaviours with a dual process model of gain and loss.

This study is survey based, with 261 paired leader–employee data points collected in the People’s Republic of China.

The results show that empowering leadership has a “double-edged” effect on employees’ innovative behaviours: it affects innovative behaviours positively through employee job engagement and negatively through emotional exhaustion. Moreover, trust in leaders moderates the mediating roles of job engagement and emotional exhaustion.

This study contends that empowering leadership has a dual impact on employees and proposes a promising model of this double-edged effect to contrast with other complex models in the empowering leadership literature. Furthermore, this study uses JD-R theory to deeply explore the dual process whereby empowering leadership influences employees’ innovative behaviour and provides practical guidance for business management.

Employee entrepreneurship has recently become an emerging area of investigation. However, due to the fragmentation of the turnover and entrepreneurship literature, no coherent theoretical framework has been developed to provide an adequate description of the employee entrepreneurial process. The purpose of this paper is to gain a deeper understanding of why and how an employee in an established organization progresses toward starting a new venture by exploring the key decision-making processes during the initial stages of employee entrepreneurship.

This study addresses the following research questions: What are the key decision-making processes during the initial stages of employee entrepreneurship? How are these decisions made, and how do they interact? This study employed a multiple case study approach, which enabled the authors to gain valuable insight into these “what” and “how” questions. The data consist of 28 in-depth employee entrepreneurship cases.

Based on an in-depth study of 28 cases, this study constructs a comprehensive model of the dynamic and interactive decision-making processes that lead to employee entrepreneurship. In particular, the findings reveal that rather than being a linear staged activity, employee entrepreneurship is an inherently iterative process that involves a set of interrelated subdecision-making processes related to turnover, team entrepreneurship and partner recruitment that entail multiple iterations and feedback loops based on an individual's cognitive judgment.

By illustrating and clarifying the importance of the effects of different initial motivations and the attributes of the network in the course of the employee entrepreneurship decision-making process, this study integrates the turnover and entrepreneurship literature and makes significant contributions to the current literature on employee entrepreneurship. Moreover, this study complements research investigating entrepreneurial team formation by providing a detailed understanding of how the lead entrepreneur and the prospective partner make mutual choices during the entrepreneurial team formation process.

Because unethical behaviour pervades in organisations, how to inhibit the interpersonal influence of unethical behaviour has become increasingly important. This study aims to integrate the deontic justice theory and affective events theory to examine the relationship between an individual’s unethical behaviour and his or her peers’ vicarious learning by highlighting the mediating effect of peers’ moral anger and the moderating effect of task interdependence on this relationship.

Data were collected in two waves from 254 employees of a large manufacturing company in the People’s Republic of China.

The hypothesised moderated mediation model was supported. Specifically, as expected, peers’ moral anger mediated the negative relationship between an individual’s unethical behaviour and peers’ vicarious learning. Task interdependence moderated the direct relationship between the individual’s unethical behaviour and his or her peers’ moral anger and the indirect relationship between an individual’s unethical behaviour and his or her peers’ vicarious learning via the peers’ moral anger such that these relationships were stronger when the level of task interdependence was higher.

This study argues that the deontic justice theory is a supplement for the social learning theory in explaining the interpersonal influence of unethical behaviour. Drawing on the deontic justice theory, this study demonstrates that an individual’s unethical behaviours are unlikely to be rewarded or accepted, and by integrating the theories of deontic justice and affective events, offers a rationale for the emotional mechanism that underlies the interpersonal influence of unethical behaviour.

This paper aims to examine the effect of chief executive officers (CEOs’) global experience (GE) on the Chinese firms’ outward foreign direct investment (OFDI) and provides new insights on how CEOs’ foreign study and education experiences may affect firms’ OFDI. Further, this paper examines whether CEO power and state ownership have a positive moderating effect on the relationship between CEOs’ GE and firms’ OFDI.

This study used panel data of Chinese manufacturing companies in 2007-2016 to examine different hypotheses. The authors tested them using a zero-inflated negative binomial regression model to shed light on the effect of CEOs’ GE on the firms’ OFDI.

This study found that CEOs’ GE generally promotes Chinese firms’ OFDI. CEOs’ foreign study experience has a stronger effect than foreign education experience. Further, CEO power and state ownership have a positive moderating effect on the relationship between CEOs’ GE and firms’ OFDI.

The findings have two important implications for managers and policy-makers. First, globally experienced CEOs are vital for firms to succeed in today’s highly competitive global environment. Second, CEO power is important in firms’ OFDI decision-making.

The authors use path dependency and upper echelons theories to show that GE, particularly foreign study experience, enables CEOs to take advantage of available resources in the market and institutional environment to create a path for the firm to expand globally.

This study seeks to explore the intricate relationship among supply chain transparency, digitalization and idiosyncratic risk, with a specific focus on newly public firms. The objective is to determine whether supply chain transparency effectively mitigates idiosyncratic risk within this context and to understand the potential impact of digitalization on this dynamic interplay.

The study utilizes data from Initial Public Offerings (IPOs) on China’s Growth Enterprise Board (ChiNext) over the last five years, sourced from the CSMAR database and firms’ annual reports. The research covers the period from 2009 to 2021, observing each firm for five years post-IPO. The final sample comprises 2,645 observations from 529 firms. The analysis employs the Hausman test, considering the panel-data structure of the sample and favoring fixed effects over random effects. Additionally, it applies the high-dimensional fixed effects (HDFE) estimator to address unobserved heterogeneity.

The analysis initially uncovered an inverted U-shaped relationship between supply chain transparency and idiosyncratic risk, indicating a delicate equilibrium where detrimental effects diminish and beneficial effects accelerate with increased transparency. Moreover, this inverted U-shaped relationship was notably more pronounced in newly public firms with a heightened level of firm digitalization. This observation implies that firm digitalization amplifies the impact of transparency on a firm’s idiosyncratic risk.

This study distinguishes itself by providing distinctive insights into supply chain transparency and idiosyncratic risk. Initially, we introduce and substantiate an inverted U-shaped correlation between supply chain transparency and idiosyncratic risk, challenging the conventional linear perspective. Secondly, we pioneer the connection between supply chain transparency and idiosyncratic risk, especially for newly public firms, thereby enhancing comprehension of financial implications. Lastly, we pinpoint crucial digital conditions that influence the relationship between supply chain transparency and idiosyncratic risk management, offering a nuanced perspective on the role of technology in risk management.

Personal thermal management in functional textiles is in increasing demand for health care, outdoor activity and energy saving. Thus, developing new strategies is highly desired for radiative cooling and/or heating by manipulation of the transmissivity, reflectivity and absorptivity of the textiles within solar energy and human body heat radiation ranges.

Inorganic additives including TiO2, Fe2O3, carbon black (CB), graphene and mica were incorporated into polymer films. The inorganic additives' full spectrum properties and thermal responses were comprehensively investigated.

The CB composite film showed the highest absorptivity over the full solar to human body radiation spectrum. The mica-white (mica-w) (mica coated with TiO2) and mica-red (mica-r) (mica coated with Fe2O3) composites showed the lowest solar energy absorptivity and a strong body heat radiation reflectivity. Furthermore, according to composites' thermal responses to the simulated solar and human body radiations, CB and mica are promising for both cooling and heating when applied in dual-functional thermal management textiles.

Research has limitation related the amount of additives which can be added to textile. When powder is added to polyester yarn, the amount is limited by 2–3%. When powder is added to the composite which is used for printing, the amount of powder is limited by 5%.

A lot of apparel, especially sport apparel, contains prints. Decoration is one part of print application. Now, a lot of companies work under development of different additives, which provide additional properties to apparel. The closest targets for powder added to prints are cooling and heat retention. Quite often, inorganic additives possess dual properties: the inorganic additives may be heat reflective which his needed for heat retention, but may have high-thermal conductivity, which works well for cooling. Human body has complicated mechanism of heat exchange: convection, radiation and moisture evaporations play main role. The same additive may be cooling if there is a contact with skin but may be heating (IR reflective) if placed in the second or third layer. Thus, effect is needed to be studied first before real application.

This work could provide a comprehensive guideline for the rational design and application of thermal management composite textile materials by revealing the full solar to human body radiation performance of a series of inorganic materials.

The purpose of this paper is to investigate the explosive performance and explosion damage mechanism of T-beam bridge structure.

On the basis of the existing specification, two T-beam bridge models were designed and fabricated. Test specimens of different explosive dosage and different blast height were carried out. The mechanical process, failure mode, blast damage model, damage identification mechanism and blast evolution law and quantitative evaluation were taken into account.

The results revealed that the web plate fracture failure is the key to the unstable failure of the whole T-beam bridge. The explosion failure phenomenon and blast damage evaluation criterion of RC T-beam bridge was divided into five stages: the original cracks stage of concrete material (D = 0 ∼ 0.1), the fractures initiation stage of concrete material (D = 0.1 ∼ 0.3), the stable expansion stage of cracks in concrete material (D = 0.3 ∼ 0.55), the unstable expansion stage of cracks in concrete material (D = 0.55 ∼ 0.8), the explosion fracture of steel bars and the overall instability and damage of the bridge (D = 0.8 ∼ 1.0), which can also be described as basically intact, slight damage, moderate damage, severe damage and collapsed.

The research result will provide basis for the antiknock evaluation and damage repair technical specifications of the RC T-beam bridge.

The research results of damage evaluation serve as a basis for damage repair and reinforcement of bridge structures after explosion.

Disruptions and shortages of drugs have become severe problems in recent years, which has triggered strong media and public interest in the topic. However, little is known about the factors that can be associated with the increased frequency of shortages. In this paper, the authors analyze the drivers of drug shortages using empirical data for Germany, the fourth largest pharmaceutical market.

The authors use a dataset provided by the German Federal Institute for Drugs and Medical Devices (Bundesinstitut für Arzneimittel und Medizinprodukte [BfArM]) with 425 reported shortages for drug substances (DSs) in the 24-month period between May 2017 and April 2019 and enrich the data with information from additional sources. Using logistic and negative binomial regression models, the authors analyze the impact of (1) market characteristics, (2) drug substance characteristics and (3) regulatory characteristics on the likelihood of a shortage.

The authors find that factors like market concentration, patent situation, manufacturing processes or dosage form are significantly associated with the odds of a shortage. The authors discuss the implications of these findings to reduce the frequency and severity of shortages.

The authors contribute to the empirical research on drug shortages by analyzing the impact of market characteristics, DS characteristics and regulatory characteristics on the reported shortages. The authors’ analysis provides a starting point for better prioritizing efforts to strengthen drug supply as it is currently intensely discussed healthcare authorities.

System dynamics is a whole-system modelling and learning approach, useful for tackling non-linear problems, such as sustainable urban development. The purpose of this paper is to review system dynamics applications in the simulation of sustainable urban development over a period from 2005 to 2017.

The analysis reveals that the number of applications of system dynamics modelling in the area of urban sustainable development increased in the analysed period. Research has changed its focus from the modelling of environmental problems to more complex models, portraying the multidimensional socio-economic processes that have an impact on the sustainability of urban development. Analysed case studies most often use the behaviour reproduction test for model validation, but without a unified approach. In most cases, modelling has been done in China, Germany and the USA, while urban development in the Eastern European countries, Africa and Latin America has not often been investigated. This paper indicates the knowledge gaps and suggests future research directions.

Papers that report the use of system dynamics modelling reveal a wide range of applications in urban sustainability. The analysis shows significant emphasis on environmental problems, while the interest for modelling social problems has been increasing during the last several years. Most of the modelled problems examine the sustainability of resources (land, water) and waste management, which are used for insights into the reasons for the system behaviour, forecasting future behaviour and policy testing.

The presented models were developed in most cases for the purpose of understanding the phenomena examined, as well as the future use of the models in policy planning. This brings us back to the need for greater stakeholder involvement, not only in the initial phase, but also during the whole modelling process, which could increase understanding, use and ownership of the models in the future, and thus increase their practical application.