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Insight in the temperature distribution on the internal and external surface of the nacelle is of great importance during the design phase of an aircraft. However, detailed information is not always needed. In a preliminary project stage or during parametric optimization, short analysis times are often more crucial than high accuracy. In such cases, the global insight in the temperature levels suffices to gain understanding of the relevance and influence of certain parameters. Nevertheless, estimating the maximum temperature for the most adverse conditions should also be done before a prototype is built. Therefore, this study aims to present and compare a simplified and an advanced methodology for the analysis of engine bay cooling and ventilation systems as well as heat transfer in the nacelle in a small airplane equipped with a turboprop engine in the tractor arrangement.

Both approaches included conductive, convective and radiative heat transfer in the engine bay of the small airplane I-23 as well as heat conduction in the nacelle made of material with anisotropic thermal conductivity. The one-dimensional (1D) model assumed that the nacelle with the air flow and engine was represented by a lumped thermal model in which heat was exchanged between the different lumped segments (the nodes) and the flowing air and engine. The three-dimensional (3D) model was based on the continuous control volume approach for heat, fluid flow and thermal radiation as well as on realizable k-ε turbulence model. Both models used commercial software.

The temperature distribution at the internal and external surface of the top nacelle was calculated. The 1D model predicted a temperature per node (per segment) while the 3D model was able to determine its values accurately and find the location of hot spots. Considering the complex geometry of the engine bay and nacelle and the assumed simplification, the obtained 1D and 3D results agreed quite well.

Both models will help in the development of new ventilation and cooling systems of the engine bay and nacelle as well as in the selection of materials for parts of the top cowling in the newly redesigned airplane I-23 equipped with a turboprop engine. In addition, the methodology presented in this paper might be applied in the development of other airplanes.

The 1D and 3D models of complex heat transfer inside the engine bay and in the nacelle of the newly re-designed airplane I-23 were elaborated and compared.

The purpose of this chapter is to analyze the impact of public agricultural Research and Development (R&D) investments on agricultural productivity and long-term food security to derive policy recommendations. The methodological approach is based on the application of the state-of-the art Computable General Equilibrium (CGE) model to R&D. By endogenizing R&D in global CGE models, it is possible to assess the impact of different public R&D policies on the food availability and food access of food security. This study found that R&D investments bring positive effects on the food access dimension of food security, particularly in places such as Sub-Saharan Africa where prices are expected to grow significantly by 2050, as agricultural land becomes scarcer and more expensive. Doubling the R&D intensity would soften the land constraints and substantially decelerate food prices, thus preventing the deterioration of living standards of rural households and leading to a gain in daily caloric consumption. The impact of alternative agricultural R&D policies on the various dimensions of food security has not been analyzed using a CGE framework, which enables capturing both the benefits and costs from R&D investments. Modeling the dynamic accumulation of R&D stocks makes it possible to analyze the effects of R&D on food security over time.

The purpose of this paper is to explore the notion and function of silent landscape in a touristic experience by presenting the findings of a study on silent retreats in a Buddhist meditation retreat center in Northern India.

This study adopted a sensory ethnography approach applied through interviews and participant observation methods conducted during and after nine retreats in a meditation center.

This study suggests that silent landscapes are not only backdrops of touristic experiences but can be considered as inter-subjective performative and resourceful milieu of engagement that intertwine intimate embodied experiences with broader social and cultural values.

Despite landscapes having been thoroughly investigated in tourist studies, this paper underlines the pertinence of mobilizing the lens of other forms of presences such as affects, embodiment, sensoriality and sonority to understand the inter-relation between tourists-selves and the surrounding world encountered during their travels.

The purpose of this paper is to propose a methodology to integrate the construction Supply Chain (SC) through the application of Building Information Modeling (BIM) and Supply Chain Management (SCM). It features a renovation case as a proof-of-concept.

After analyzing the relevant gaps in the literature, the research followed a modeling approach. The proposed model merged product-, process- and organizational models in a graph-based model to represent and analyze a BIM-based SCM project.

Presently, the information flows of the construction SC are vague. BIM is an aspiring integrator of information flows for construction. The proposed model for SC integration with BIM, offers an approach to identify the project complexities in relation to organizational structures, roles and interactions and integrate the industry.

Currently BIM-enabled SCM is not very widely applied in the industry. However, the authors report the increasing interest of most construction stakeholders to engage in the application of the two, after acknowledging the benefits from the individual approaches. Since this combination is quite rare, the research uses a retrospective real-world case study of a SC project with an imaginary application of BIM.

Thus far, there is no formal model to represent the interactions of the SC actors along with BIM. The unique combination of a product and a process model, i.e. BIM, with an organizational model aims at integrating the information flows of the SC. The proposed model aims at analyzing and supporting the BIM-enabled SCM in Architecture Engineering and Construction.

This paper aims to test whether servant leaders lead followers to socially interact more frequently, closely and personally with peers, and if this social interaction links servant leaders with employees’ personal social capital, both in terms of bonding (networks linking employees of a similar kind) and bridging (networks linking agents of different kinds).

Data were collected from 403 employees from 59 large Spanish hotels. Structural equation modeling was used to test the hypotheses.

The results reveal that servant leadership has a positive effect on bonding and bridging, which is mediated by employees’ social interactions with peers inside and outside their groups, respectively.

The findings suggest that hotel managers should adopt servant leadership to facilitate social interactions at work, thus allowing employees to individually gain personal assets that improve the hotel’s social capital resources.

This is the first study to analyze whether servant leadership shapes personal social capital in business settings. Moreover, it is the first to show the mechanisms (social interactions with peers inside and outside their groups) through which managerial servant leadership encourages this valuable personal asset in hotels.

Chinese agri‐food chains consist of the millions of small scale farmers, who are not well structured and organized in the supply chain. Owing to market liberalization and globalization, one of the most challenging issues along agri‐food chains in China is becoming the issue of how to link these small‐scale farmers into the modern chains. Consequently, it is essential for both policy makers and private sectors to understand the governance structure in agri‐food supply chains. Therefore, the purpose of this paper is to develop a theoretical framework for supply chain governance, including its antecedents and consequences, as well as a series of hypotheses for empirical testing.

A conceptual framework of chain governance is proposed in this study, where governance structure consists of two dimensions: contractual governance and relational governance. The study intends to propose a complementary relationship between contracts and relational aspects, such as trust, in the Chinese context. Future research is needed to empirically test this model.

The proposed conceptual model is unique, since the majority of the articles addressing this topic focuses on contract farming while limited research touches upon the issues of trust and relations. However, a combination of both contracting and relationships are seldom addressed.

This paper evaluates a novel concept of two dimensional governance structure in the agri‐food supply chain, where transaction cost economics theory and relational theory are combined to study the governance relationships between small scale producers in China and their buyers.

This study explores how chatbot gender and symbolic service recovery may improve the satisfaction of angry customers in the context of service failures. It provides a strategy for companies to deploy chatbots effectively in customer anger.

This research relies upon a systematic literature review to propose three hypotheses, and we recruit 826 participants to examine the effect of chatbot gender on angry customers through one lab study and one field study.

This research shows that female chatbots are more likely to increase the satisfaction of angry customers than male chatbots in service failure scenarios. In addition, symbolic recovery (apology vs. appreciation) moderates the effect of chatbot gender on angry customers. Specifically, male (vs. female) chatbots are more effective in increasing the satisfaction of angry customers when using the apology method, whereas female (vs. male) chatbots are more effective when using the appreciation method.

The rapid advancements in artificial intelligence technology have significantly enhanced the effectiveness of chatbots as virtual agents in the field of interactive marketing. Previous research has concluded that chatbots can reduce negative customer feedback following a service failure. However, these studies have primarily focused on the level of chatbot anthropomorphism and the design of conversational texts, rather than the gender of chatbots. Therefore, this study aims to bridge that gap by examining the effect of chatbot gender on customer feedback, specifically focusing on angry customers following service failures.

The coronavirus disease 2019 (COVID-19) pandemic drastically changed work arrangements, but COVID-19's impact on employee leave utilization is unclear. The authors sought to understand how sick leave and vacation leave utilization changed during the pandemic among clinical and non-clinical departments at an academic medical center (AMC).

Clinical departments were defined as work units with a primary mission of providing direct patient care. Per-person, per-month leave utilization data were obtained from the AMC's time-keeping system for 3 clinical departments and 4 non-clinical departments in the first 12 months of the pandemic and the preceding 12 months. Monthly data for each department were analyzed with mixed-effects regression.

Available data represented 402 employees from 3 clinical departments and 73 employees from 4 non-clinical departments. The authors found no statistically significant change in sick leave utilization among either clinical or non-clinical departments. Vacation leave utilization decreased during the pandemic by 5.9 h per person per month in non-clinical departments (95% confidence interval [CI]: −8.1, −3.8; p < 0.001) and by 3.0 h per person per month in clinical departments (95% CI: −4.3, −1.7; p < 0.001).

Among employees in clinical departments, the authors found no increase in sick leave utilization and a decrease in vacation utilization. These findings are concerning for presenteeism, risk of burnout or understaffing resulting in workers' inability to take time away from work in clinical departments.