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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.

The purpose of this study is to investigate the impact of varying baffle height and spacing distance on heat transfer and cooling performance of electronic components in a baffled horizontal channel, using a Cu-H₂O nanofluid under mixed convection and laminar flow.

The mathematical model is two-dimensional and comprises a system of four governing equations, such as the conservation of continuity, momentum and energy. To obtain numerical solutions for these equations, the finite volume method was used for discretization. A validation process was performed by comparing this study’s results with those of previously published studies. The comparison revealed a close agreement. The numerical study was performed for a wide range of key parameters: The baffle height (0 ≤ h ≤ 0.7), the spacing distance between baffle and blocks (0.25 ≤ w ≤ 3), the Grashof and Reynolds numbers are kept equal to 10⁴ and 75, respectively, the channel aspect ratio is L/H = 10, and the volume fraction of Cu nanoparticles is fixed at φ = 5%.

The results of the study reveal a significant improvement in heat transfer in terms of total Nusselt number of the top and bottom hot components, which exhibited an improvement of 16.89% and 17.23% when the baffle height increases from h = 0 to h = 0.7. Additionally, the study found that reducing the distance between the baffle and the electronic components up to a certain limit can improve the heat transfer rate. Therefore, the optimal height of the baffle was found to be no lower than 0.6, and the recommended distance between the heaters and the baffle was 0.5.

This study provides valuable insights into the optimization of the design of baffled channels for improved heat transfer performance. The findings of study can be used to improve heat exchangers and cooling systems in various applications. The use of Cu-H₂O nanofluid under mixed convection and laminar flow conditions in channel with baffle and electronic components is also unique, making this study an original contribution to the field.

This research investigates how to optimize storage location assignment to decrease the order picking time and the waiting time of orders in the staging area of low-temperature logistics centers, with the goal of reducing food loss caused by temperature abuse.

The authors applied ABC clustering to the products in a simulated database of historical orders modeled after the actual order pattern of a large cold logistics company; then, the authors mined the association rules and calculated the sales volume correlation indices of the ordered products. Finally, the authors generated three different simulated order databases to compare order picking time and waiting time of orders in the staging area under eight different storage location assignment strategies.

All the eight proposed storage location assignment strategies significantly improve the order picking time (by up to 8%) and the waiting time of orders in the staging area (by up to 22%) compared with random placement.

The results of this research are based on a case study and simulated data, which implies that, if the best performing strategies are applied to different environments, the extent of the improvements may vary. Additionally, the authors only considered specific settings in terms of order picker routing, zoning and batching: other settings may lead to different results.

A storage location assignment strategy that adopts dispersion and takes into consideration ABC clustering and shipping frequency provides the best performance in minimizing order picker's travel distance, order picking time, and waiting time of orders in the staging area. Other strategies may be a better fit if the company's objectives differ.

Previous research on optimal storage location assignment rarely considered item association rules based on sales volume correlation. This study combines such rules with several storage planning strategies, ABC clustering, and two warehouse layouts; then, it evaluates their performance compared to the random placement, to find which one minimizes the order picking time and the order waiting time in the staging area, with a 30-min time limit to preserve the integrity of the cold chain. Order picking under these conditions was rarely studied before, because they may be irrelevant when dealing with temperature-insensitive items but become critical in cold warehouses to prevent temperature abuse.

This study used an integrated model that incorporates the Technology Acceptance Model (TAM) and the Theory of Planned Behaviour (TPB) to empirically investigate how eco-gamification stimulates users' sustainability knowledge and, consequently, their pro-sustainable intentions through the mediating roles of sustainable knowledge and psychological and social norms. Thus, the study aims to examine users'’ experiences with the JouleBug app, which is designed to encourage users to complete at least one daily green task.

After a trial period of two weeks, a total of 360 participants completed the post-game survey during the research process.

The findings from the structural equation modeling and data analysis indicated a good fit for the model. The findings demonstrate that usefulness, ease of use and enjoyment of eco-gamification enrich users' sustainability knowledge, which, in turn, strongly influences their pro-sustainable intentions. According to the findings, the three factors of TPB have a significant impact on users' pro-sustainability intentions. Both sustainable knowledge and social cues play mediating roles in such relationships.

This study advocates that eco-gamification can be used as a platform to modify tourists’ pro-sustainability intentions in emerging tourism and technology destinations such as Egypt. Hence, this study offers significant information to tourism planners and other stakeholders on tourists’ behavioural intentions.

This study examined the effectiveness of an integrated model of TAM and TBP in predicting tourists’ intentions to use eco-gamification to improve the sustainability of tourist destinations.

本研究采用结合技术接受模型（TAM）和计划行为理论（TPB）的综合模型, 旨在探究生态游戏化如何提升用户对可持续性的认知, 从而影响他们支持环保行为的意愿。通过研究可持续性知识以及心理和社会规范在其中的中介作用来实现这一目标。因此, 本研究调查了用户使用JouleBug应用程序的体验, 该应用程序旨在鼓励用户每天完成至少一个环保任务。

在为期两周的试验期后, 共有360名参与者在研究过程中完成了后测问卷调查。

通过结构方程模型和数据分析, 研究结果表明模型拟合良好。研究发现, 生态游戏化的实用性、易用性和乐趣能够丰富用户的可持续性知识, 从而强烈影响他们支持可持续性的意愿。研究结果还显示, 计划行为理论（TPB）的三个因素对用户的支持可持续性意愿有显著影响。可持续性知识和社会提示在这些关系中发挥着中介作用。

本研究主张, 生态游戏化可以作为一个平台, 用于引导游客在埃及等新兴旅游和科技目的地中支持可持续性的意愿。因此, 该研究为旅游规划者和其他利益相关者提供了有关游客行为意向的重要信息。

本研究考察了TAM和TPB综合模型在预测游客使用生态游戏化改善旅游目的地可持续性意愿方面的有效性。

Este estudio utilizó un modelo integrado que combina el Modelo de Aceptación Tecnológica (TAM) y la Teoría del Comportamiento Planificado (TPB) para investigar cómo la eco-gamificación aumenta el conocimiento de los usuarios sobre la sostenibilidad y, en consecuencia, sus intenciones para actuar favorablemente en el medio ambiente. Esto se logró analizando cómo el conocimiento sostenible y las normas psicológicas y sociales actuaban como mediadores. Para ello, la investigación examina las experiencias de los usuarios con la aplicación JouleBug, diseñada para fomentar que los usuarios realicen al menos una tarea verde diaria.

Tras un período de prueba de dos semanas, un total de 360 participantes completaron la encuesta posterior al juego durante el proceso de investigación.

Los resultados del modelo de ecuaciones estructurales y análisis de datos indicaron un buen ajuste del modelo. Los resultaros evidencian que la utilidad, facilidad de uso y disfrute de la eco-gamificación enriquecen el conocimiento de sostenibilidad de los usuarios y, a su vez, influye significativamente en sus intenciones pro-sostenibilidad. Conforme a los resultados, los tres factores de la TPB tienen un impacto significativo en las intenciones pro-sostenibilidad de los usuarios. Tanto el conocimiento sostenible como las señales sociales desempeñan roles mediadores en estas relaciones.

Este estudio aboga por el uso de la eco-gamificación como una plataforma para modificar las intenciones pro-sostenibilidad de los turistas en destinos emergentes de turismo y tecnología, como Egipto. Por tanto, esta investigación proporciona información significativa para los planificadores de turismo y otros interesados en las intenciones conductuales de los turistas.

Este estudio examinó la eficacia de un modelo integrado de TAM y TPB para predecir las intenciones de los turistas de utilizar la eco-gamificación para mejorar la sostenibilidad de los destinos turísticos.

The purpose of this study was to examine the impact of strategic leadership (SL) on business operational resilience (OR) in the hotel industry in Egypt, namely, during and after the pandemic. This investigation also aimed to explore the mediating function of crisis response strategies (CRSs) and organisational e-readiness (Oe-R) in this relationship.

The researchers conducted a cross-sectional study using a questionnaire as the primary data collection method. Using partial least squares structural equation simulation (PLS-SEM), the study used a comprehensive sample that targets the general managers of all five-star hotels in Egypt.

Results indicated that SL has a positive impact on CRSs and Oe-R. Furthermore, the results reveal a positive influence of Oe-R on both CRSs and hotel OR. On the other hand, CRSs do not influence hotel OR. The findings showed that CRSs fully mediate the link between SL and OR. However, CRSs do not serve as a mediator between Oe-R and OR. Furthermore, the findings showed that Oe-R partially mediates the link between SL and both OR and CRSs.

The study yields unique and valuable theoretical and practical insights to guide hotel leaders and managers towards adaptive recovery and resilience in turbulent and crisis-ridden environments by demonstrating that the combined mediating function of CRS and Oe-R is more effective in strengthening the relationship between SL and OR.

This study represents a pioneering investigation that establishes a correlation between SL and OR, either through direct or indirect means. The research examines the involvement of CRSs and Oe-R as collaborative mediators in this relationship. Previous studies undertaken in the hotel industry and service sector have not investigated this specific element.

Nowadays, businesses globally are scrambling to keep up with the latest trend of adopting Information Technology (IT) tools like electronic customer relationship management (E-CRM). The study aims to examine and describe the impact of information availability, system security and quality on consumer satisfaction and E-CRM efficacy in shopping websites.

Communication in the period of the fourth industrial revolution was performed face to face and via the use of technological communication tools. The growth of information and communication technology (ICT) has compelled businesses to embrace E-CRM to strengthen client relationships and boost profitability, loyalty and satisfaction. E-CRM is implemented to establish communication with customers. So the major goal of the investigation is to look at the function of influencing variables in E-CRM system efficiency in online buying. The present study's statistical population is limitless. The sample size for structural equations is determined to be 384, utilizing the sample measurement technique. A research framework is developed with four hypotheses resulting from previous research to measure the sample. SMART PLS software is used to assess the suggested model and the data received from the questionnaire.

According to the findings, availability of information, information quality and security influence user satisfaction. Therefore, considering the dimensions could be a great step in the improvement of the E-CRM effectiveness. The outcomes also showed that online shopping sites should help customers observe the accordance between the received services and their needs' features.

Despite many efforts to complete the article, the low sample size is one of the limitations of this article. Also, the study has only been evaluated in one country, so generalization of results should be made with caution.

The E-CRM process is a continuous learning process where information about the customer is transformed into a customer relationship. Also, customer satisfaction is the core concern of any system, and such systems must assess customer satisfaction levels by incorporating a procedure. Many research findings show that development managers try to enhance the quality of the relationship with development managers' customers. The study recommends that both designers and managers focus on security, system quality and access to information to boost customer satisfaction.

The research discusses and identifies the key factors that must be considered while providing the solutions of E-CRM. The study helps managers to accelerate E-CRM systems. Also, the paper supports the field of the managers-orientated perspective in E-CRM.

As the core technology of blockchain, various consensus mechanisms have emerged to satisfy the demands of different application scenarios. Since determining the security, scalability and other related performance of the blockchain, how to reach consensus efficiently of consensus mechanism is a critical issue in the blockchain.

The paper opted for a research overview on the blockchain consensus mechanism, including the consensus mechanisms' consensus progress, classification and comparison, which are complemented by documentary analysis.

This survey analyzes solutions for the improvement of consensus mechanisms in blockchain that have been proposed during the last few years and suggests future research directions around consensus mechanisms. First, the authors outline the consensus processes, the advantages and disadvantages of the mainstream consensus mechanisms. Additionally, the consensus mechanisms are subdivided into four types according to their characteristics. Then, the consensus mechanisms are compared and analyzed based on four evaluation criteria. Finally, the authors summarize the representative progress of consensus mechanisms and provide some suggestions on the design of consensus mechanisms to make further advances in this field.

This paper summarizes the future research development of the consensus mechanisms.

Scholars mainly propose and establish theoretical models of cumulative fatigue damage for their research fields. This review aims to select the applicable model from many fatigue damage models according to the actual situation. However, relatively few models can be generally accepted and widely used.

This review introduces the development of cumulative damage theory. Then, several typical models are selected from linear and nonlinear cumulative damage models to perform data analyses and obtain the fatigue life for the metal.

Considering the energy law and strength degradation, the nonlinear fatigue cumulative damage model can better reflect the fatigue damage under constant and multi-stage variable amplitude loading. In the following research, the complex uncertainty of the model in the fatigue damage process can be considered, as well as the combination of advanced machine learning techniques to reduce the prediction error.

This review compares the advantages and disadvantages of various mainstream cumulative damage research methods. It provides a reference for further research into the theories of cumulative fatigue damage.

This paper aims to design a global controller that is operational throughout all flight modes and less dependent on an accurate model.

By adopting the interconnection and damping assignment passivity-based control (IDA-PBC) technology and compensating extra inputs for handling the unknown dynamics and time-varying disturbances, a model-free control (MFC)-based global controller is proposed.

Test results indicate that the designed controllers are more suitable for actual flight as they have smaller position tracking errors and energy consumption in all flight phases than the excellent model-free controller intelligent-PID.

The designed global controller, which works in all flight modes without adjusting its structure and parameters, can realize a stable and accurate tracking control of a tail-sitter and improve the resistance to unknown disturbances and model uncertainties.

The newly-designed controller is considered as an enhanced version of the traditional MFC. It further improves the control effect by using the poorly known dynamics of the system and choosing the IDA-PBC as the control auxiliary input. This method eliminates the unnecessary dynamics to continuously stabilize the vehicle with suitable energy consumption covering its entire flight envelope.

There are many studies explaining the innovation activity determinants. Nowadays, the digitalization of sales, the influence of social media, user-driven innovation (UDI) activity might be considered as one of the crucial sources for the development of new products within the research and development activity. Undertaken research is therefore aimed at determining whether the marketing orientation, i.e. the purchasing behavior of customers, affects the innovation activity of R&D departments that work under the usage of UDI concept.

57 R&D departments operating in Poland participated in the study. Correspondence analysis based on the Burt matrix and Cramer's V correlation coefficients was used for the analysis.

The analysis shows that R&D departments in Poland using marketing research and examining consumer purchasing behavior, positively assess the effects of using the UDI concept in R&D departments. They implement it to create or improve products or services offered on the market, especially in the field of customization, while using information from national research and development units in Poland. The motivation for these activities is mainly to increase the assortment level.

The conducted study covers only R&D departments in Poland, thus it is worth extending the generalization of the results. In terms of future research directions, it's worth to analyze the data from R&D departments in other countries. The results of such studies could be used for comparative analyses. The main limitation of the research is that the research sample was 57 R&D departments of enterprises operating in Poland. Therefore, the research results can't be generalized to all the R&D departments in Poland.

The findings could help researchers and practitioners improve their understanding of the determinants of innovation activity, especially its relationship to marketing orientation and UDI practices.

The research regarding marketing orientation of enterprises and its influence on innovation activity is extremely important due to the general change of the conditions for the functioning of enterprises and building their competitive advantage. Knowledge in this area is still insufficient and research gaps are still being exposed. The article presents the correlation between the marketing orientation and customer behavior within the UDI activity and effects of innovation activity of R&D departments being under investigation.