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The purpose of this study is to numerically and experimentally investigate the natural convection heat transfer in flat plates and plates with square, trapezoidal and triangular corrugations.

This work is an extension of the previous studies by Verderio et al. (2021a, 2021b, 2021c, 2021d, 2022a). An experimental apparatus was built to measure the plates’ temperatures during the natural convection cooling process. Several physical parameters were evaluated through the experimental methodology. Free and open-source computational tools were used to simulate the experimental conditions and to quantitatively and qualitatively evaluate the thermal plume characteristics over the plates.

The numerical results were experimentally validated with reasonable accuracy in the range of studied RaLP for the different plates. Empirical correlations of Nu¯LPexp=f(RaLP), h¯conv=f(RaLP) and Nu¯LPexp⋅(A/AP)=f(RaLP), with good accuracy and statistical representativeness, were obtained for the studied geometries. The convective thermal efficiency of corrugated plates (Δη), as a function of RaLP, was also experimentally studied quantitatively. In agreement with the findings of Oosthuizen and Garrett (2001), the experimental and numerical results proved that the increase in the heat exchange area of the corrugations has a greater influence on the convective exchange and the thermal efficiency than the disturbances caused in the flow (which reduce h¯conv). The plate with trapezoidal corrugations presented the highest convective thermal efficiency, followed by the plates with square and triangular corrugations. It was also proved that the thermal efficiency of corrugated plates increases with RaLP.

The results demonstrate that corrugated surfaces have greater thermal efficiency than flat plates in heating and/or cooling systems by natural convection. This way, corrugated plates can reduce the dependence on auxiliary forced convection systems, with application in technological areas and Industry 4.0.

The empirical correlations obtained for the corrected Nusselt number and thermal efficiency for the corrugated plate geometries studied are original and unpublished, as well as the experimental validation of the developed three-dimensional numerical code.

Hotels offer high-quality guest experiences to positively impact their emotions, satisfaction, perceived value, word-of-mouth (WOM) and electronic word-of-mouth (eWOM). This study aims to investigate the impacts of the quality perceived by hotel guests on their positive emotions, negative emotions, perceived value and satisfaction; verify the impacts of the price on perceived value and satisfaction; examine the impacts of satisfaction on WOM and eWOM; and test the moderating effect of hotel guests’ behavioural engagement on social networking sites (HGBE-SNS) on the relationship between satisfaction and eWOM.

This survey included 371 guests who assessed their experiences at three Brazilian hotels. Structural equation modelling tested the hypothetical model supported by the stimulus-organism-response (S-O-R) theory (Mehrabian and Russell, 1974).

The quality perceived by hotel guests (stimulus) positively impacts perceived value, positive emotions and satisfaction and negatively affects negative emotions (organism). Price (stimulus) negatively impacts perceived value but does not affect satisfaction. Perceived value positively impacts satisfaction. Satisfaction positively impacts WOM and eWOM (responses). The HGBE-SNS moderates the relationship between satisfaction and eWOM.

To the best of the authors’ knowledge, this study is the first that simultaneously demonstrates the relationships between perceived quality, price, perceived value, positive and negative emotions, satisfaction, WOM, eWOM and HGBE-SNS. Hotels must offer their guests high-quality services to positively impact’ perceived value, positive emotions, satisfaction and WOM. Low prices boost the perceived value but do not directly increase guest satisfaction. Satisfied hotel guests share their experiences via WOM, but high HGBE-SNS is crucial to boost eWOM.

Los hoteles ofrecen experiencias de alta calidad a sus huéspedes para influir positivamente en sus emociones, satisfacción, valor percibido, boca a boca (WOM) y boca a boca electrónico (eWOM). Este estudio tiene como objetivo a) investigar el impacto de la calidad percibida por los huéspedes del hotel en sus emociones positivas, emociones negativas, valor percibido y satisfacción; b) verificar el impacto del precio en el valor percibido y la satisfacción; c) examinar el impacto de la satisfacción en el WOM y eWOM; d) probar el efecto moderador del compromiso conductual de los huéspedes del hotel en las redes sociales (HGBE-SNS) en la relación entre satisfacción y eWOM.

En esta encuesta participaron 371 huéspedes que evaluaron sus experiencias en tres hoteles brasileños. La modelización de ecuaciones estructurales puso a prueba el modelo hipotético apoyado en la teoría estímulo-organismo-respuesta (S-O-R) (Mehrabian y Russell, 1974).

La calidad percibida por los clientes del hotel (estímulo) influye positivamente en el valor percibido, las emociones positivas y la satisfacción, y negativamente en las emociones negativas (organismo). El precio (estímulo) afecta negativamente al valor percibido, pero no a la satisfacción. El valor percibido afecta positivamente a la satisfacción. La satisfacción afecta positivamente al WOM y al eWOM (respuestas). El HGBE-SNS modera la relación entre satisfacción y eWOM.

Este estudio es el primero que demuestra simultáneamente las relaciones entre calidad percibida, precio, valor percibido, emociones positivas y negativas, satisfacción, WOM, eWOM y HGBE-SNS. Los hoteles deben ofrecer a sus clientes servicios de alta calidad para influir positivamente en el valor percibido, las emociones positivas, la satisfacción y el WOM. Los precios bajos aumentan el valor percibido pero no incrementan directamente la satisfacción de los huéspedes. Los huéspedes satisfechos comparten sus experiencias a través del WOM, pero un alto nivel de HGBE-SNS es crucial para impulsar el eWOM.

酒店提供高质量的宾客体验, 对宾客的情绪、满意度、感知价值、口碑（WOM）和电子口碑（eWOM）产生积极影响。本研究旨在 a) 调查酒店客人感知到的质量对其积极情绪、消极情绪、感知价值和满意度的影响; b) 验证价格对感知价值和满意度的影响; c) 检验满意度对 WOM 和电子口碑的影响; d) 检验酒店客人在社交网站上的行为参与（HGBE-SNS）对满意度和电子口碑之间关系的调节作用。

本次调查包括 371 位客人, 他们对自己在巴西三家酒店的入住体验进行了评估。结构方程模型检验了由刺激-组织-反应（S-O-R）理论（Mehrabian 和 Russell, 1974 年）支持的假设模型。

酒店客人感知到的质量（刺激因素）对感知价值、积极情绪和满意度有积极影响, 而对消极情绪（有机体）有消极影响。价格（刺激因素）对感知价值有负面影响, 但不影响满意度。感知价值对满意度有积极影响。满意度对 WOM 和 eWOM（反应）产生积极影响。HGBE-SNS 可调节满意度与网络口碑之间的关系。

本研究首次同时展示了感知质量、价格、感知价值、积极和消极情绪、满意度、WOM、eWOM 和 HGBE-SNS 之间的关系。酒店必须为客人提供高质量的服务, 才能对 “感知价值"、"积极情绪"、"满意度 “和 “WOM “产生积极影响。低价会提升感知价值, 但不会直接提高客人满意度。满意的酒店客人会通过 WOM 分享他们的体验, 但高 HGBE-SNS 对促进 eWOM 至关重要。

Despite the school organizational culture broad literature, there is still a gap on culture and educational management, mainly in the public environment. To fill out this space, this article wants to point out the cultural factors that creates school management change in the Brazilian public school context.

The sample is a polar multi-case approach with two high performance and two low performance Brazilian schools. The authors conducted 12 interviews, three each school, with school principal, pedagogical coordinator and administrative officer. To analyze the data, the authors applied synthetic analysis to identify the cultural factors and your conduciveness to change in schools.

The results point out organizational culture as low understood in public municipal schools. These results also indicate the cultural dimensions power distance, uncertainty avoidance, individualism, masculinity, long-term orientation and indulgence as influencers of school management. Therefore, organizational culture is a factor to change and improve performance in public school management.

Despite the low comprehensiveness by the school managers, the authors pointed out the importance of the cultural factors, such as power distance, uncertainty avoidance, individualism, masculinity, long-term orientation and indulgence, in the school management. Future research could assess quantitatively the cultural factors presented here.

The paper provides cultural aspects in the school environment that should be considered in the school management improvement process and school principals’ actions.

The results fulfil the gap of organizational culture and school management in the public sector studies, by pointing out cultural factors of change in the school environment.

This study investigates the process of praxeological transformation developed in an early childhood institution using context-based staff educational practices as strategy to support the professional development of educators. It aims at developing a pedagogy that recognises and legitimises children as full-right citizens, thus valuing their competences to participate.

The context-based staff educational practices were taken in an ecological perspective thus recognising an interconnection between professional development, curriculum and organisational development. This is a longitudinal case study (four years) framed in a qualitative constructivist approach, using action research, context-based staff development and participatory childhood pedagogy as means to change educational practices. It is founded in the principles of the Childhood Association's pedagogical approach for children learning and teachers' development, as well as on the Effective Early Learning Project as a reference for monitoring and evaluating quality co-construction. The main objectives of the study were defined around the reconstruction of children and educators' images, to create democratic participatory understandings of central actors that will develop a situated pedagogy of respect and learning. The reconceptualisation of the image of the child, based on the listening of his/her voices, has been key for their right to participate and a professional motivation for kindergarten teachers to change their daily professional practices. The data gathered reveal the understanding of children as competent persons and active learners who construct complex forms of thought and action. This long process of learning led the participants to realise the importance of participatory childhood pedagogies.

The evolution of tourism must be framed into policies that aim a development model perspective for the destinations, based on the analysis of economic, political, and social indicators. Therefore, emerging destinations, located in territories with low population density, should be a target of a careful strategy policy, considering the characteristics of the region. In particular, the disaster caused by the pandemic context (i.e., COVID-19) implied profound changes in tourism thinking, planning, and development of regions in Portugal and throughout the world. The present chapter proposes the creation of a tourism monitoring system for Arouca (Portugal), a territory classified as Low-Density Territory, with specific characteristics. The monitoring will involve the planning and management of database, at the disposal of all stakeholders, ensuring that the tourism flows in analysis do not get overwhelmed, allowing the discussion of opportunities and threats for the territory, based on the partnership between the population, public and private sector, adjusted to the social, cultural, economic, and environment perception. Will also be considered the perspective of the local community from Arouca's region, the main actors from the territory such as Geopark Association of Arouca and the City Council, according to the surveys used as data basis of this study, along with statistics analysis.

The purpose of this study is to investigate the influence of firm-specific investor sentiment on Brazilian companies’ accrual-based earnings management between 2010 and 2018. The paper aims to bring deeper insight into the relationship between the investor expectations and managers’ decision-making in an emerging market.

The authors use the quantitative approach and apply a multiple linear regression model to test the relationship among the abnormal accruals, the firm-specific investor sentiment index and the control variables. The final sample includes data from 175 companies, between 2010 and 2018.

These results reveal a negative association between firm-specific investor sentiment and accrual-based earnings management, which could mean that the risk propensity of managers to manipulate earnings increases when they face known losses in the capital market.

The research findings provide a valuable understanding of how emerging capital market expectations can influence managerial decisions, such as accrual-based earnings management. The geographical area of study was limited to only Brazil.

Previous studies on developed markets show that market-wide investor sentiment positively influences accrual-based earnings management. However, the present study shows that the firm-specific investor sentiment index has a significant and negative relationship with Brazilian companies’ earnings manipulation, whereas market sentiment indicates contradictory relationship in previous studies in the country.

El propósito de este estudio es investigar la influencia del sentimiento de los inversionistas a nivel de empresa en la manipulación contable de las empresas brasileñas entre 2010 y 2018. El documento pretende aportar una visión más profunda sobre la relación entre las expectativas de los inversores y la toma de decisiones de los gestores en un mercado emergente.

usamos el enfoque cuantitativo y aplicamos un modelo de regresión lineal múltiple para probar la relación entre las acumulaciones anormales, el índice de sentimiento de los inversores a nivel de empresa y las variables de control. La muestra final incluye datos de 175 empresas, entre 2010 y 2018.

Los resultados revelan una asociación negativa entre el sentimiento de los inversores a nivel de empresa y la manipulación contable basada em acumulaciones, lo que podría significar que la propensión al riesgo de los administradores a manipular las ganancias aumenta cuando enfrentan pérdidas conocidas en el mercado de capitales.

los resultados de la investigación proporcionan una valiosa comprensión de cómo las expectativas de los mercados de capitales emergentes pueden influir en las decisiones de gestión, como la manipulación contable basada en acumulaciones. El área geográfica de estudio se limitó únicamente a Brasil y, en consecuencia, los hallazgos y conclusiones del estudio tuvieron sus límites.

estudios anteriores sobre mercados desarrollados muestran que el sentimiento de los inversores a nivel de mercado influye positivamente en la manipulación contable. Sin embargo, el presente estudio muestra que el índice de sentimiento de los inversores a nivel de empresa tiene una relación significativa y negativa con la manipulación de las ganancias de las empresas brasileñas, mientras que el sentimiento del mercado indica una relación contradictoria en estudios anteriores en el país.

Hotels provide high-quality guest experiences to generate perceived value for money (PVM), positively influencing word-of-mouth (WOM) and electronic word-of-mouth (eWOM) communication. This study aims to (1) verify the impacts of the perceived quality by the guests about their experiences in hotels on their PVM; (2) inspect the influence of guests' perception of hotel prices on PVM; (3) examine the impacts of guest PVM on their hotel experiences on WOM and eWOM and (4) investigate the consequences of the hotel guests' behavioural engagement on social networking sites (HGBE-SNS) on eWOM.

This quantitative and descriptive study consists of a survey with 371 guests who evaluated their experiences at three hotels in Brazil. PLS-SEM tested the hypothetical model that resorted to the stimulus-organism-response theory (S-O-R), proposed by Mehrabian and Russell (1974). Cluster Analysis compared the PVM, WOM and eWOM of groups of hotel guests with different levels of social media engagement.

Perceived quality by hotel guests positively impacts PVM. Perceived price negatively influences PVM. PVM had a positive and robust impact on WOM. PVM impacts and explains weakly eWOM. In contrast, HGBE-SNS affects and better explains eWOM than PVM.

This unprecedented investigation concomitantly exhibits the relationships between perceived quality, price, PVM, WOM, eWOM and HGBE-SNS. Hotels must offer high perceived quality experiences to influence PVM and WOM positively. PVM is unable to stimulate eWOM strongly. HGBE-SNS is pivotal for guests to share their hotel experiences through eWOM. This study suggests marketing strategies for hospitality companies to amplify customer engagement on SNS.

The purpose of this study is to numerically investigate the geometric influence of different corrugation profiles (rectangular, trapezoidal and triangular) of varying heights on the flow and the natural convection heat transfer process over isothermal plates.

This work is an extension and finalization of previous studies of the leading author. The numerical methodology was proposed and experimentally validated in previous studies. Using OpenFOAM® and other free and open-source numerical-computational tools, three-dimensional numerical models were built to simulate the flow and the natural convection heat transfer process over isothermal corrugation plates with variable and constant heights.

The influence of different geometric arrangements of corrugated plates on the flow and natural convection heat transfer over isothermal plates is investigated. The influence of the height ratio parameter, as well as the resulting concave and convex profiles, on the parameters average Nusselt number, corrected average Nusselt number and convective thermal efficiency gain, is analyzed. It is shown that the total convective heat transfer and the convective thermal efficiency gain increase with the increase of the height ratio. The numerical results confirm previous findings about the predominant effects on the predominant impact of increasing the heat transfer area on the thermal efficiency gain in corrugated surfaces, in contrast to the adverse effects caused on the flow. In corrugations with heights resulting in concave profiles, the geometry with triangular corrugations presented the highest total convection heat transfer, followed by trapezoidal and rectangular. For arrangements with the same area, it was demonstrated that corrugations of constant and variable height are approximately equivalent in terms of natural convection heat transfer.

The results allowed a better understanding of the flow characteristics and the natural convection heat transfer process over isothermal plates with corrugations of variable height. The advantages of the surfaces studied in terms of increasing convective thermal efficiency were demonstrated, with the potential to be used in cooling systems exclusively by natural convection (or with reduced dependence on forced convection cooling systems), including in technological applications of microelectronics, robotics, internet of things (IoT), artificial intelligence, information technology, industry 4.0, etc.

To the best of the authors’ knowledge, the results presented are new in the scientific literature. Unlike previous studies conducted by the leading author, this analysis specifically analyzed the natural convection phenomenon over plates with variable-height corrugations. The obtained results will contribute to projects to improve and optimize natural convection cooling systems.

The purpose of this study is to investigate the influence of light intensity and sources of carbon and nitrogen on the cultivation of Spirulina maxima.

Cultures were carried out in a modified Zarrouk medium using urea, sodium acetate and glycerol. A Taguchi experimental design was used to evaluate the effect on the production of biocompounds: productivities in biomass, carbohydrates, phycocyanin and biochar were analyzed.

Statistical data analysis revealed that light intensity and sodium acetate concentration were the most important factors, being significant in three of the four response variables studied. The highest productivities in biomass (46.94 mg.L⁻¹.d⁻¹), carbohydrates (6.11 mg.L⁻¹.d⁻¹), phycocyanin (3.62 mg.L⁻¹.d⁻¹) and biochar (22, 48 mg.L⁻¹.d⁻¹) were achieved in experiment 4 of the Taguchi matrix, highlighting as the ideal condition for the production of biomass, carbohydrates and phycocyanin.

Sodium acetate and urea can be considered, respectively, as potential sources of carbon and nitrogen to increase Spirulina maxima productivity. From the results, an optimized cultivation condition for the sustainable production of bioproducts was obtained.

This work focuses on the study of the influence of light intensity and the use of alternative sources of nitrogen and carbon on the growth of Spirulina maxima, as well as on the influence on the productivity of biomass and biocompounds. There are few studies in the literature focused on the phycocyanin production from microalgae, justifying the need to deepen the subject.

The purpose of this study was to identify the relationship between training and financial performance in cooperative organizations.

To achieve this goal, the fixed-effect panel regression technique was used, from a single database containing hours and amounts invested in training by 35 large Brazilian agribusiness cooperatives over 10 years as the main independent variable of the econometric model. Financial performance was operationalized by the Net Margin and ROE.

It was possible to identify a positive relationship between expenditure on training and the future rate of return and profitability of the organizations in question. The results also indicate that this relationship grows stronger over the first three years after the investments are made and ceases to exist after this period. The findings are robust with regard to a series of alternative explanations and contribute to understanding the relationship between training and organizational performance in financial terms, considering the extent and duration of training.

The originality this study is justified by the pioneering spirit of presenting direct evidence linking investment in training and financial performance and the duration of this relationship. Thus, the study makes a significant contribution to the construction of knowledge on the subject.