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Wall-modeled large eddy simulation (LES) is a practical tool for solving wall-bounded flows with less computational cost by avoiding the explicit resolution of the near-wall region. However, its use is limited in flows that have high non-equilibrium effects like separation or transition. This study aims to present a novel methodology of using high-fidelity data and machine learning (ML) techniques to capture these non-equilibrium effects.

A precursor to this methodology has already been tested in Radhakrishnan et al. (2021) for equilibrium flows using LES of channel flow data. In the current methodology, the high-fidelity data chosen for training includes direct numerical simulation of a double diffuser that has strong non-equilibrium flow regions, and LES of a channel flow. The ultimate purpose of the model is to distinguish between equilibrium and non-equilibrium regions, and to provide the appropriate wall shear stress. The ML system used for this study is gradient-boosted regression trees.

The authors show that the model can be trained to make accurate predictions for both equilibrium and non-equilibrium boundary layers. In example, the authors find that the model is very effective for corner flows and flows that involve relaminarization, while performing rather ineffectively at recirculation regions.

Data from relaminarization regions help the model to better understand such phenomenon and to provide an appropriate boundary condition based on that. This motivates the authors to continue the research in this direction by adding more non-equilibrium phenomena to the training data to capture recirculation as well.

This paper seeks to understand how a new elite, known as the cork aristocracy, emerged in the Bordeaux wine field, France, between 1850 and 1929 as wine merchants replaced aristocrats. Classic class and status perspectives, and their distinctive social closure dynamics, are mobilized to illuminate the individual and organizational transformations that affected elite wineries grouped in an emerging classification of the Bordeaux best wines. We build on a wealth of archives and historical ethnography techniques to surface complex status and organizational dynamics that reveal how financiers and industrialists intermediated this transition and how organizations are deeply interwoven into social change.

This study aims to explore the formation mechanism of aerodynamic noise of a high-speed maglev train and understand the characteristics of dipole and quadrupole sound sources of the maglev train at different speed levels.

Based on large eddy simulation (LES) method and Kirchhoff–Ffowcs Williams and Hawkings (K-FWH) equations, the characteristics of dipole and quadrupole sound sources of maglev trains at different speed levels were simulated and analyzed by constructing reasonable penetrable integral surface.

The spatial disturbance resulting from the separation of the boundary layer in the streamlined area of the tail car is the source of aerodynamic sound of the maglev train. The dipole sources of the train are mainly distributed around the radio terminals of the head and tail cars of the maglev train, the bottom of the arms of the streamlined parts of the head and tail cars and the nose tip area of the streamlined part of the tail car, and the quadrupole sources are mainly distributed in the wake area. When the train runs at three speed levels of 400, 500 and 600 km·h⁻¹, respectively, the radiated energy of quadrupole source is 62.4%, 63.3% and 71.7%, respectively, which exceeds that of dipole sources.

This study can help understand the aerodynamic noise characteristics generated by the high-speed maglev train and provide a reference for the optimization design of its aerodynamic shape.

The purpose of this study is to analyze the influence of the emotional experience (EE) and the image of the tourist destination on the satisfaction of the domestic tourist and his behavioral intentions, represented through the word of mouth (WOM) and his revisit intention.

The information obtained through a personal survey to 382 local tourists was refined and subjected to structural equation analysis. Analyses conducted with SPSS 20.0 and AMOS 20 software confirmed the existence of interesting significant relationships.

The results show that positive destination image and different experiences are considered to be the main elements that promote positive emotions and satisfaction for tourists, leading to a higher eagerness to spread WOM recommendations and to revisit a destination. The results also verify that interactions with the difficult-replacement services and with residents create strong positive EEs for female visitors, so that they are more willing to revisit a destination than males.

Eco-destination managers should provide more difficult-replacement services and create an enjoyable and unique experience for tourists to enhance their satisfaction and positive behavioral intentions.

The results provide some important implications and insights about the marketing theory groundwork of EE and satisfaction, such as how they are to be conceptualized and established and how interactive relationships are formed among them in the ecotourism context.

El propósito del estudio es analizar la influencia de la experiencia emocional y la imagen del destino turístico sobre la satisfacción del turista nacional y sus intenciones de comportamiento, representadas a través del WOM y su intención de reinterpretación.

La información obtenida a través de una encuesta personal a 382 turistas locales fue refinada y sometida a análisis de ecuaciones estructurales. Los análisis realizados con el software SPSS 20.0 y AMOS 20 confirmaron la existencia de interesantes relaciones significativas.

Los resultados exponen que la imagen positiva de los destinos y las experiencias varias se consideraron como los elementos principales que les promocionan las emociones y satisfaciones positivas a los turistas, lo que llevan a un gran deseo de difundir boca a boca y de volver a visitar. Además, verifican los resultados que las interacciones de turistas con los servicios de reemplazo diferente y con los residentos locales les han creado las experiencias de emoción fuerte a los visitantes femeninas, entonces desean que vuelven a visitar los destinos que los masculinos.

Los directores de eco-destino deben proveer más servicios disponibles de reemplazo diferente a los turistas lo que les generan maravillosa diversa experiencia a ellos, así empodean la satisfaction y intenciones de conducta.

Los resultados proveen algunas implicaciones importantes y visiones del fundamento de la teoría del marketing de la experiencia emocional y la satisfacción como en cuál manera que se establecen o conceptualizan y como las relacciones interactivas son formada en el contexto de eco-turismo.

本研究旨在分析情感体验和旅游目的地形象对国内游客满意度及其行为意向的影响, 行为意向通过口碑推荐和目的地重游意向来表示。

通过调研382名当地游客, 对获取得信息进行提炼, 进行了结构方程分析。使用SPSS 20.0和AMOS 20软件进行分析, 证实了存在着有趣的显著关系。

结果显示, 积极的目的地形象和不同的体验被认为是促进游客积极情绪和满意度的主要因素, 从而使游客更热衷于传播口碑、推荐和重游目的地。结果还表明, 与困难置换服务机构的互动, 以及与居民的互动会为女性游客带来强烈的正向情感体验, 使得女性游客相比于男性更愿意重游目的地。

生态旅游目的地管理者应提供更多的困难置换服务, 并为游客创造愉快、独特的体验, 以提高游客的满意度和积极的行为意向。

研究结果为情感体验和满意度的营销理论基础工作提供了一些重要的启示, 例如, 在生态旅游背景下, 如何对它们进行概念化和建立, 以及它们之间如何形成互动关系。

The literature on ‘mixed’ families (in which members are socially viewed as ‘different’ due to their varying ethnicities and/or nationalities) identifies several stakes of mixedness. One of them arises from childbirth, after which parents need to give name(s) to their offspring. How does the parent–child dyad understand the giving of names in their mixed family? What does naming children unveil regarding interpersonal interactions and the value of children within this social unit? The chapter delves into these questions through a case study of forenaming children in Filipino-Belgian families in Belgium. Interview data analysis reveals two modes of forenaming in these families: individualisation through single forenames and reinforcement of collective affiliation through compound forenames. Through the analytical framework of social relatedness, this chapter uncovers the way the act of naming a child bridges families based on biological and social ties, generations, and parents' nations of belonging in their transnational spaces. The complex process of naming reflects the power dynamics not only within the parental couple but also within the wider set of social relations. Although the use of forename(s) in everyday life and in legal terms differ, the value of children in the mixed families studied lies in their symbolic role as social bridges linking generations and non-biological relationships, the then and now, and the here and there.

This chapter looks at the discursive dimension of the working environment in research and higher education organizations; more specifically at neoliberal managerial discourse and at how it participates in shaping the way researchers, teachers and support staff perceive themselves and their experiences. It is based on a multiple case study and combines an intersectional and a socio-clinical approach. The empirical data is constituted by in-depth interviews with women conducted in Ireland and Chile, and includes some observations made in France. A thematic analysis of individual narratives of self-ascribed experiences of being bullied enables to look behind the veil drawn by managerial discourse, thus providing insights into power vectors and power domains contributing to workplace violence. It also shows that workplace bullying may reinforce identification to undervalued social categories. This contribution argues that neoliberal managerial discourse, by encouraging social representations of “neutral” individuals at work, or else celebrating their “diversity,” conceals power relations rooting on different social categories. This process influences one’s perception of one’s experience and its verbalization. At the same time, feeling assigned to one or more of undervalued social category can raise the perception of being bullied or discriminated against. While research has shown that only a minority of incidents of bullying and discrimination are reported within organizations, this contribution suggests that acknowledging the multiplicity and superposition of categories and their influence in shaping power relations could help secure a more collective and caring approach, and thus foster a safer work culture and atmosphere in research organizations.

There has been a great deal of discussion in recent years focusing on the need for teachers to have leadership responsibilities and to participate in the decision-making processes within their respective schools. Unfortunately, these discussions are often filled with suggestions and recommendations that completely miss the point about teacher leadership. Leadership for teachers has little to do with titles and responsibilities, yet it has everything to do with their performance in the classroom. A true teacher leader is one who can create a classroom environment that fosters high achievement among the students. Teachers that can influence and gain the respect of their students are in essence bona fide leaders.

The typical approach of modeling the aerodynamics of an aircraft is to develop a complete database through testing or computational fluid dynamics (CFD). The database will be huge if it has a reasonable resolution and requires an unacceptable CFD effort during the conceptional design. Therefore, this paper aims to reduce the computing effort required via establishing a general aerodynamic model that needs minor parameters.

The model structure was a preconfigured polynomial model, and the parameters were estimated with a recursive method to further reduce the calculation effort. To uniformly disperse the sample points through each step, a unique recursive sampling method based on a Voronoi diagram was presented. In addition, a multivariate orthogonal function approach was used.

A case study of a flying wing aircraft demonstrated that generating a model with acceptable precision (0.01 absolute error or 5% relative error) costs only 1/54 of the cost of creating a database. A series of six degrees of freedom flight simulations shows that the model’s prediction was accurate.

This method proposed a new way to simplify the model and recursive sampling. It is a low-cost way of obtaining high-fidelity models during primary design, allowing for more precise flight dynamics analysis.

The purpose of this study is to investigate the transport phenomena of smoke flow in a semi-open vertical shaft.

The large eddy simulation (LES) method was used to model the movement of fire-induced thermal flow in a full-scale vertical shaft. With this model, different fire locations and heat release rates (HRRs) were considered simultaneously.

It was determined that the burning intensity of the fire is enhanced when the fire attaches to the sidewall, resulting in a larger continuous flame region in the compartment and higher temperatures of the spill plume in the shaft compared to a center fire. In the initial stage of the fire with a small HRR, the buoyancy-driven spill plumes incline toward the side of the shaft opposite the window. Meanwhile, the thermal plumes are also directed away from the center of the shaft by the entrained airflow, but the inclination diminishes as HRR increases. This is because a greater HRR produces higher temperatures, resulting in a stronger buoyancy to drive smoke movement evenly in the shaft. In addition, a dimensionless equation was proposed to predict the rise-time of the smoke plume front in the shaft.

The results need to be verified with experiments.

The results could be applied for design and assessment of semi-open shafts.

This study shows the transport phenomena of smoke flow in a vertical shaft with one open side.

In the world of public school education everything depends on good leadership. Sadly, many of our schools administrators can't differentiate the difference between leading and managing; far too many of them don't know the first thing about fundamental leadership principles. In short, they don't understand the fundamentals of Mission Oriented Leadership, the need for top-down leadership, or the critical differences between leadership and management. A cursory review of the selection process for school administrators, and the graduate level curriculums for those who seek a degree in school administration, clearly supports the contention that policymakers and educators are under the misconception that anyone can be taught or trained to be an effective school leader. Nothing could be further from the truth.