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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.

This study aims to investigate the determinants of the food security status of participants and non-participants of livestock extension services living under similar socioeconomic conditions as livestock farming households in the Feed the Future zone of Bangladesh.

Cross-sectional data of 906 farm-households extracted from a total of 2064 from the Feed the Future representative Bangladesh Integrated Households Survey 2018 were used. A triple hurdle model combined with a structural equation model were used to analyze the data. The causal relationship between food security status, livestock extension services, technology adoption and women's empowerment was investigated by estimating structural equation modeling with second-order latent factors.

The results indicate that livestock extension services have increased livestock technology adoption and have a positively significant (p < 0.01) relationship with household wealth, food security, welfare and women's empowerment.

The results suggest that livestock extension services have an impact on new technology adoption and enhancing women's empowerment; thus, the services should be widely made available in the region.

The peer review history for this article is available at: https://publons.com/publon/10.1108/IJSE-11-2021-0647.

The paper aims to expand the scope of application of the lattice Boltzmann method (LBM), especially in the field of aircraft engineering. The traditional LBM is usually applied to incompressible flows at a low Reynolds number, which is not sufficient to satisfy the needs of aircraft engineering. Devoted to tackling the defect, the paper proposes a developed LBM combining the subgrid model and the multiple relaxation time (MRT) approach. A multilayer adaptive Cartesian grid method to improve the computing efficiency of the traditional LBM is also employed.

The subgrid model and the multilayer adaptive Cartesian grid are introduced into MRT-LBM for simulations of incompressible flows at a high Reynolds number. Validated by several typical flow simulations, the numerical methods in this paper can efficiently study the flows under high Reynolds numbers.

Some numerical simulations for the lid-driven flow of cavity, flow around iced GLC305, LB606b and ONERA-M6 are completed. The paper presents the investigation results, indicating that the methods are accurate and effective for the separated flow after icing.

LBM is developed with the addition of the subgrid model and the MRT method. A numerical strategy is proposed using a multilayer adaptive Cartesian grid method and its treatment of boundary conditions. The paper refers to innovative algorithm developments and applications to the aircraft engineering, especially for iced wing simulations with flow separations.

Policymakers are developing government-level pandemic response strategies (GPRS) to assist architecture, engineering and construction (AEC) enterprises. However, the effectiveness of the GPRS has not been assessed. Therefore, this study aims to investigate the interrelationships between GPRS and AEC enterprises. To achieve that aim, the study objectives are to compare GPRS effectiveness between small-medium and large AEC enterprises, develop groupings to categorize interrelated GPRS and evaluate the effectiveness of the GPRS and interrelated constructs.

A systematic literature review and semi-structured interviews with 40 AEC industry professionals were carried out, generating 22 GPRS. Then, questionnaire survey data was collected among AEC professionals. In total, 114 valid survey answers were received and analyzed using the Kruskal–Wallis H test, normalized mean analysis, factor analysis and fuzzy synthetic evaluation.

Small-medium enterprises have four distinct critical GPRS: “form a special task force to provide support in maneuvering COVID-19,” “provide infrastructure investment budgets to local governments,” “develop employee assistance programs that fit all types of working groups” and “diversify existing supply chain.” Large enterprises have two distinct critical GPRS: “provide help in digitalizing existing construction projects” and “mandate COVID-19 as force majeure.” Eighteen GPRS can be categorized into the following five constructs: “market stability and financial aid,” “enterprise capability management,” “supply chain improvement,” “law and policy resources” and “information and workforce management.” The former two constructs are more effective than other GPRS constructs.

This is the first paper that evaluates the effectiveness of GPRS for AEC enterprises, providing new evidence to policymakers for well-informed decision-making in developing pandemic response strategies.

This chapter tells the story of how the concept of Pareto efficiency was shipped from Lausanne to the modern US theory of competitive general equilibrium, focusing on the specific role of Maurice Allais. It identifies similarities in both epistemological approach and theoretical achievements realized first by Pareto, then by Allais, and finally by Debreu and Arrow and Hahn. It also shows that these similarities are not casual, since historical circumstances account for the influence of Pareto on Allais and later of Allais on Arrow and Debreu.

Following the ‘Sarkozy’ era (2007–2012), France has engaged in ‘zero-tolerance’ policies, which have brought an increasing number of people into the criminal justice system (CJS). In an already extremely impoverished CJS, these policies have led to serious financial problems and have made an already existing prison overcrowding problem worse. Consequently, the CJS has gradually opted for a McDonald (Ritzer, 2019; Robinson, 2019) type of offender processing, whether in prosecutor-led procedures (representing roughly half of all penal procedures: Ministry of Justice, 2019) or in the sentencing phase (Danet, 2013). A similar trend has been found in probation and in prisoner release (in French: ‘sentences’ management).

The prison and probation services, which merged in 1999, have since then been in a position to benefit from the 1958 French Republic Constitution, which places the executive in a dominant position and notably allows it to draft the bills presented to a rather passive legislative power (Rousseau, 2007) and even to enjoy its own set of normative powers (‘autonomous decrees’ – Hamon & Troper, 2019). By way of law reforming (2009, 2014, and 2019 laws), the prison and probation services have thus embraced the McDonaldisation ethos. Their main obsession has been to early release as many prisoners as possible in order to free space and to accommodate more sentenced people. To do so, the prison services have created a series of so-called ‘simplified’ early release procedures, where prisoners are neither prepared for nor supported through release, where they are deprived of agency and where due process and attorney advice are removed. Behind a pretend rehabilitative discourse, the executive is only interested in efficiently flushing people out of prison; not about re-entry efficacy. As Ritzer (2019) points out, McDonaldisation often leads to counter-productive or absurd consequences. In the case of early release, the stubborn reality is that one cannot bypass actually doing the rehabilitative and re-entry work. I shall additionally argue that not everything truly qualifies as an early release measure (Ostermann, 2013). Only measures which respect prisoners’ agency prepare them for their release, which support them once they are in the community, which address their socio-psychological and criminogenic needs, and which are pronounced in the context of due process and defence rights truly qualify as such. As it is, French ‘simplified’ release procedures amount to McRe-entry and mass nothingness.

This chapter presents a critical analysis of the wealth current practices of multinational firms as wealth predators; and relevant references from the theory of multinational corporations and globalization from a Marxist perspective. The Marxist approach has also contributed to a theory of the self-expansion of capital (internationalization of the circuits of capital) on a global scale, within an analysis of the differentiation and of inequality.

Shortly before the Second World War, a woman who had never accepted her orphan status, Gabrielle Bonheur Chanel, nicknamed ‘Little Coco’ by her father and known as ‘Coco’ to her relatives, became the first women in history to build a world-class industrial empire. By 1935, Coco, a fashion designer and industry captain, was employing more than 4,000 workers and had sold more than 28,000 dresses, tailored jackets and women's suits. Born into a poor family and raised in an orphanage, she enjoyed an intense social life in Paris in the 1920s, rubbing shoulders with artists, creators and the rising stars of her time.

Thanks to her entrepreneurial skills, she was able to innovate in her methods and in her trendsetting approach to fashion design and promotion. Coco Chanel was committed and creative, had the soul of an entrepreneur and went on to become a world leader in a brand new sector combining fashion, accessories and perfumes that she would help shape. By the end of her life, she had redefined French elegance and revolutionized the way people dressed.

This study aims to introduce a dynamic perspective of tourism resilience by analyzing tourism demand in Spain during the 2020 and 2021 summers in the context of the COVID-19 pandemic.

This study uses regression and Lasso-type methods to demonstrate a great explanatory capacity of past determinants to explain the tourism demand of the Spanish provinces.

Results show how the previous specialization of the domestic market, the density and the geographic location related to the type of product are behind the bulk of the territorial differences in demand resilience, although in 2021 there has been a process of adaptation to the new context.

This study contributes to the theoretical understanding of tourist behavior and tourism destination management by introducing the concept of resilience dynamics of destinations.

The results are useful, on the one hand, for tourist destinations to understand the different stages of recovery from a shock, and on the other hand, to go in deep in consumer behavior after a shock.

These findings represent a paradigm shift in the static conception of resilience in tourism.

本文通过分析 2020 年和 2021 年夏季 COVID-19 大流行背景下西班牙的旅游需求, 介绍了旅游业复原力的动态视角。

我们使用回归和套索型方法来证明过去的决定因素解释西班牙各省旅游需求的能力。

我们的结果表明, 尽管 2021 年出现了一个适应新环境的过程, 但之前国内市场的专业化、密度以及提供的产品的位置相关类型是造成需求弹性的大部分地域差异的原因。

这些发现代表了旅游业复原力静态概念的范式转变。

本研究通过引入目的地特定弹性动态的概念, 有助于对游客行为和旅游目的地管理的理论理解。

一方面, 研究结果有助于旅游目的地了解从冲击中恢复的不同阶段, 另一方面有助于探索冲击后的消费者行为。

Este artículo presenta una perspectiva dinámica sobre la resiliencia del turismo mediante el análisis de la demanda turística en España durante los veranos de 2020 y 2021 en el contexto de la pandemia de COVID-19.

Utilizamos métodos de regresión y tipo Lasso para demostrar la capacidad de los determinantes pasados para explicar la demanda turística en las provincias españolas.

Nuestros resultados muestran cómo la especialización previa del mercado interno, la densidad y el tipo de producto ofrecido relacionado con la ubicación están detrás del grueso de las diferencias territoriales en la resiliencia de la demanda, aunque en 2021 hubo un proceso de adaptación al nuevo contexto.

Estos hallazgos representan un cambio de paradigma en la concepción estática de la resiliencia en el turismo.

Este estudio contribuye a la comprensión teórica de los comportamientos turísticos y la gestión de los destinos turísticos al introducir el concepto de dinámica de resiliencia específica del destino.

Por un lado, los resultados son útiles para que los destinos turísticos comprendan las diferentes etapas de recuperación de un shock y, por otro lado, para explorar el comportamiento del consumidor después de un shock.

Graphical abstract: The evaluation of the vulnerability of tourism.