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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 intention of the empirics is to contribute to the general understanding of investor responses to market price shocks. The authors review assumptions about investor behavior in response to price shocks and investigate alternative rebalancing heuristics.

The authors use market data over 40 years to define market shocks. Portfolio rebalancing implements constrained Markowitz mean-variance (MV) heuristics.

Momentum rebalancing in portfolio management outperforms contrarian rebalancing in the study interval. Sensitivity analysis by decade, sector constraints and proportion of security holdings bought or sold continue to support momentum rebalancing.

The results are consistent with under-responding to price shocks at consensus levels in financial markets. The theoretical background provides a basis for experimental lab studies of shocks of different magnitudes under conditions in which participants have information on the levels of other participants and a condition in which they can only observe their previous estimates.

Managing portfolios in the face of price disturbances of different magnitudes is informed by empirical studies and their implications for investor behavior.

This is the first study the authors can locate that uses market data with alternative rebalancing heuristics to estimate price returns from the respective heuristics over a time interval of 40 years. The authors support the results with sensitivity estimates and consider implications for the underlying agent heuristics in light of background studies.

This study aims to propose an aerodynamic force decomposition which, for the first time, allows for thrust/drag bookkeeping in two-dimensional viscous and unsteady flows. Lamb vector-based far-field methods are used at the scope, and the paper starts with extending recent steady compressible formulas to the unsteady regime.

Exact vortical force formulas are derived considering inertial or non-inertial frames, viscous or inviscid flows, fixed or moving bodies. Numerical applications to a NACA0012 airfoil oscillating in pure plunging motion are illustrated, considering subsonic and transonic flow regimes. The total force accuracy and sensitivity to the control volume size is first analysed, then the axial force is decomposed and results are compared to the inviscid force (thrust) and to the steady force (drag).

Two total axial force decompositions in thrust and drag contributions are proposed, providing satisfactory results. An additional force decomposition is also formulated, which is independent of the arbitrary pole appearing in vortical formulas. Numerical inaccuracies encountered in inertial reference frames are eliminated, and the extended formulation also allows obtaining an accurate force prediction in presence of shock waves.

No thrust/drag bookkeeping methodology was actually available for oscillating airfoils in viscous and compressible flows.

The vulnerability of the tourism industry to an array of risks, encompassing family-related, small- and medium-sized enterprise-specific, strategic, tourism-specific and external factors, highlights the landscape within which small and medium family enterprises (SMFEs) operate. Although SMFEs are an important stakeholder in the dynamic tourism sector, they are not one homogenous group of firms, but have different strategic orientations. This study aims to investigate the interplay between strategic orientation and risk perception to better understand SMFEs risk perception as it is impacting their decision-making processes, resilience and long-term survival. The authors investigate how different strategic orientations contribute to different perspectives on risk among owner-managers.

Based on a qualitative data corpus of 119 face-to-face interviews, the authors apply various coding rounds to better understand the relationship between strategic orientations and the perceptions of risks. Firstly, the authors analysed the owner–manager interviews and identified three groups of different strategic orientations: proactive and sustainability-oriented SMFE, destination-affirmative and resilience-oriented SMFE and passive SMFE. Secondly, the authors coded the interviews for different risks identified. The authors identified that the three groups show differences in the risk perceptions.

The data unveil that the three groups of SMFEs have several differences in how they perceive risks. Proactive and sustainability-oriented SMFEs prioritize business risks, demonstrating a penchant for innovation and sustainability. Destination-affirmative and resilience-oriented SMFEs perceive a broader range of risks, tying their investments to destination development, emphasizing family and health risks and navigating competitive pressures. Passive SMFEs, primarily concerned with external risks, exhibit limited awareness of internal and strategic risks, resist change and often defer decision-making to successors. The findings underscore how different strategic orientations influence risk perceptions and decision-making processes within SMFEs in the tourism industry.

The authors contribute to existing knowledge include offering a comprehensive status quo of perceived risks for different strategic orientations, a notably underexplored area. In addition, the differences with respect to risk perception shown in the paper suggest that simplified models ignoring risk perception may be insufficient for policy recommendations and for understanding the dynamics of the tourism sector. For future research, the authors propose to focus on exploring the possible directions in which strategic orientation and risk perception influence one another, which might be a limitation of this study due to its qualitative nature.

Varying strategic orientations and risk perceptions highlight the diversity within the stakeholder group of SMFE. Recognizing differences allows for more targeted interventions that address the unique concerns and opportunities of each group and can thus improve the firm’s resilience (Memili et al., 2023) and therefore leading to sustainability destinations development. The authors suggest practical support for destination management organizations and regional policymakers, aimed especially at enhancing the risk management of passive SMFEs. Proactive SMFE could be encouraged to perceive more family risks.

Viewing tourism destinations as a complex stakeholder network, unveiling distinct risk landscapes for various strategic orientations of one stakeholder has the potential to benefit the overall destination development. The proactive and sustainability-oriented SMFEs are highly pertinent as they might lead destinations to further development and create competitive advantage through innovative business models. Passive SMFEs might hinder the further development of the destination, e.g. through missing innovation efforts or succession.

Although different studies explore business risks (Forgacs and Dimanche, 2016), risks from climate change (Demiroglu et al., 2019), natural disasters (Zhang et al., 2023) or shocks such as COVID-19 (Teeroovengadum et al., 2021), this study shows that it does not imply that SMFE as active stakeholder perceive such risk. Rather, different strategic orientations are in relation to perceiving risks differently. The authors therefore open up an interesting new field for further studies, as risk perception influences the decision-making of tourism actors, and therefore resilience.

The purpose of this conceptual paper is to explore the role of strategic leadership under conditions of uncertainty and unpredictability. The authors argue that highly improbable, but high-impact events require the upper echelons of management, traditionally the custodians of strategy formulation to offer a new kind of strategic leadership focused on new mindsets, organizational capabilities, more in tune with high uncertainty and unpredictability.

Drawing on strategic leadership, and complexity leadership theory, the authors review the literature and present a conceptual framework for exploring the nature of strategic leadership under uncertainty. The authors conceptualize organizations as complex adaptive systems and discuss the imperatives for developing new mental models for emergent leadership.

Strategic leaders have a key role to play in preparing their organizations for episodic disruptions. These include developing their adaptive capabilities and building resilient organizations to ensure their organizations cannot only bounce back after a disruption but have the capacity for transformation to new fitness levels when necessary. Strategic leaders must engage with complexity leadership by seeing their organizations as complex adaptive systems, reconfigure their leadership approaches and organizations to build strategic adaptive capability.

This is a conceptual paper and the authors cannot make any claims of causality.

Organizational leaders need to reconfigure their mental models and leadership approaches to reflect the new normal of uncertainty and unpredictability. Developing the strategic adaptive capability of organizations should prepare them for dealing with high impact events. To assure business continuity in the face of disruptions requires building flexible, adaptable business models.

The paper focuses on how managers can offer strategic leadership for a new normal that challenges some of our most cherished leadership and strategic management paradigms. The authors explore the new mental models and leadership models in an era of great uncertainty.

The paper draws extensively from Aristotle’s Poetics, a classical work on the aesthetics of drama. Drawing from symbolic and thematic elements from folklore and mythology, this paper aims to illustrate how the Poetics can be referenced as an allegorical device in the design of culture-building strategies and interventions.

This exploratory paper examines Aristotle’s “Poetics” and the range of creative expression this literature provides as a conceptual design framework for the development of a culture map in creating a distinctive organisational mythology. The Poetics articulates an Aristotelian perspective on theatre which infuses itself as a new language in offering structural and archetypical plot devices in the development of an organisational narrative.

Findings from this explorative study can provide a creative roadmap to culture practitioners and leaders, to be used as a determining reference point in developing culture maps and change management interventions.

Poetics has its detractors, notably Bertolt Brecht and Augusto Boal. Boal examines how Poetics promotes a narrative that suppresses free thinking and encourages a cult of feudal personality, therefore encouraging industrial and cultural oppression, which he rebelled against through the development of his “Theatre of the Oppressed”. This new kind of theatre discarded the Aristotelian model of thinking. Ideas proposed in the Poetics may also lend verisimilitude to the propagation of obsessive consumerism through the definitive symbolism it offers in the development of institutionalised personality cults.

The Poetics as a creatively driven reflexive study provides a forward movement in the study of culture design templates. Its definitive allegorical devices and metaphors act as action principles through which an enterprise culture and its value system can be examined and developed.

Pay-what-you-want (PWYW) is a pricing strategy implemented in a variety of settings like supermarkets and museums, in which consumers determine the price they are willing to pay for a product or service based on their perceived utility. The authors propose an analytical model to investigate the impact of PWYW delivery pricing on the online food delivery (OFD) platforms.

Using a game-theoretic model, the authors characterize the equilibrium as a function of the platform's average delivery cost and the consumer's social preferences parameters like fairness and reciprocity. The authors derive the parametric conditions under which PWYW generates higher profits for the platform compared to the traditional pay-as-asked delivery pricing.

For the PWYW strategy to be profitable, the average delivery cost to the platform should be low. Therefore, OFD platform managers should focus on reducing delivery costs. The authors also identify the feasible region in which the platform managers need to maintain the consumer's social preferences.

Under PWYW, the authors recommend that the platform managers impose a minimum delivery fee which consumers can use as a benchmark to minimize zero delivery fee payments and consumers' free-riding tendencies simultaneously. This allows OFD platforms to extract online orders from highly price-conscious consumers.

This is one of the first studies to explore the innovative application of PWYW to a particular segment of delivery pricing in OFD platforms. The authors establish that the overall consumer surplus and social welfare are higher under the PWYW strategy, forming a solid ground for its implementation in OFD platforms.

This paper aims to explore the market dynamics that led to a shift in Swedish consumers' alcohol preferences from schnapps to wine. Specifically, the study investigates how the Swedish state influenced consumers' alcohol habits and highlights the role of governance units in shaping consumer culture.

The study reconstructs the historical memory of the “Operation Vin”, a strategic marketing campaign implemented by Systembolaget from 1957 to 1985, to conceptualize the past and to uncover the structures and change dynamics of the Swedish alcohol market system. Following this approach, the research contrasts historical data from multiple sources with market-oriented ethnographical data and traces the trajectory of how the consumption of alcohol has changed as a consequence of the Swedish state’s initiatives.

The study offers two contributions to the literature in marketing and consumption history. Firstly, it uncovers the lines of actions (framing and settlement) involved in creating marketing systems and shaping consumer culture. Secondly, it explores how the state strategically leveraged its social skills to promote a specific type of alcohol consumption (wine) and to induce the Swedish consumer to cooperate in the refashioning of the alcohol field.

The authors aspire for this paper to offer valuable insights into how a state, as a governance entity, can shape consumer culture through a strategic blend of various regulatory measures, both gentle and forceful. The authors emphasize the pivotal role of social skills in fostering cooperation during the implementation of a new alcohol policy.

This paper provides valuable insights into the role of the Swedish state in shaping consumer culture and explores the strategic actions and marketing systems involved, contributing to marketing and consumption history literature.

The COVID-19 pandemic offered a unique glimpse into the resilience of construction projects, shedding light on several learning opportunities. The purpose of this paper is to develop propositions for the improvement of resilient performance in construction in the post-pandemic era.

The propositions were developed based on an empirical study in Brazil. Data collection involved the analysis of regulations, interviews with health experts, managers, and workers, in addition to non-participant observations of the use of 37 control practices in 39 construction sites comparing the work-as-imagined and the work-as-done. The practices were classified in a hierarchy of controls.

Seven propositions for the improvement of resilient performance were developed, addressing collaboration between construction companies, slack resources, new health and safety practices, production planning and control, digital technologies, visual management, and organizational culture. These propositions emphasize organizational support for resilience. This is in contrast to the nature of most observed practices (57%) that relied on administrative controls and personal protective equipment, which are measures dependent on behaviors that resemble resilience at the individual level.

Although much has been studied on COVID-19 implications for construction projects, previous empirical studies have not adopted the organizational resilience perspective as the main theoretical background.