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Subcooled flow boiling phenomenon is characterized by coolant phase change in the vicinity of the heated wall. Although coolant phase change from liquid to vapour phase significantly enhances the heat transfer coefficient due to latent heat of vaporization, eventually the formed vapor bubbles may coalesce and deteriorate the heat transfer from the heated wall to the liquid phase. Due to the poor heat transfer characteristics of the vapour phase, the heat transfer rate drastically reduces when it reaches a specific value of wall heat flux. Such a threshold value is identified as critical heat flux (CHF), and the phenomenon is known as departure from nucleate boiling (DNB). An accurate prediction of CHF and its location is critical to the safe operation of nuclear reactors. Therefore, the present study aims at the prediction of DNB type CHF in a hexagonal sub-assembly.

Computational fluid dynamics (CFD) simulations are performed to predict DNB in a hexagonal sub-assembly. The methodology uses an Eulerian–Eulerian multiphase flow (EEMF) model in conjunction with multiple size group (MuSiG) model. The breakup and coalescence of vapour bubbles are accounted using a population balance approach.

Bubble departure diameter parameters in EEMF framework are recalibrated to simulate the near atmospheric pressure conditions. The predictions from the modified correlation for bubble departure diameter are found to be in good agreement against the experimental data. The simulations are further extended to investigate the influence of blockage (b) on DNB type CHF at low operating pressure conditions. Larger size vapour bubbles are observed to move away from the corner sub-channel region due to the presence of blockage. Corner sub-channels were found to be more prone to experience DNB type CHF compared to the interior and edge sub-channels.

An accurate prediction of CHF and its location is critical to the safe operation of nuclear reactors. Moreover, a wide spectrum of heat transfer equipment of engineering interest will be benefited by an accurate prediction of wall characteristics using breakup and coalescence-based models as described in the present study.

Simulations are performed to predict DNB type CHF. The EEMF and wall heat flux partition model framework coupled with the MuSiG model is novel, and a detailed variation of the coolant velocity, temperature and vapour volume fraction in a hexagonal sub-assembly was obtained. The present CFD model framework was observed to predict the onset of vapour volume fraction and DNB type CHF. Simulations are further extended to predict CHF in a hexagonal sub-assembly under the influence of blockage. For all the values of blockage, the vapour volume fraction is found to be higher in the corner region, and thus the corner sub-channel experiences CHF. Although DNB type CHF is observed in corner sub-channel, it is noticed that the presence of blockage in the interior sub-channel promotes the coolant mixing and results in higher values of CHF in the corner sub-channel.

The faculties are crucial to education. They should have enough training facilities and be encouraged to actively contribute to high-quality education and successful learning. Faculty engagement and development activities should be explored and included in learning organizations and employee engagement in India. This paper aims to describe higher education as a learning organization. The research will also assess how faculty development programs affect faculty engagement behaviors in these institutions and if professional development mediates this effect, which has not been previously examined.

This study was conducted with quantitative data collected from 267 faculties through reliable and validated adapted questionnaires. Semistructured interviews were conducted with heads and professor-level faculties to gain insights into faculty development and engagement. Partial least squares structural equation modeling technique (PLS-SEM 3.3.6 version) was used to test the conceptually drafted model.

Faculty professional development programs shown to improve higher education faculty engagement and professional progress. The studies also showed that higher education institutions must prioritize faculty development to become learning organizations. Professional development reduced the direct effects of faculty development program (FDP) on faculty engagement. This suggests that professional growth mediates the research.

This research emphasizes and professional development to boost teacher involvement in B-Schools. Management must design faculty development programs to construct professional development and learning organizations, according to the results. Developing and writing rules that encourage faculty engagement in such internal and external programs would also enhance their academic and administrative abilities and assist higher education institutions become learning organizations.

The study is one of the few to examine the impact of faculty development programs and professional development on faculty engagement in higher education institutions, particularly B-Schools, and its competitive mediating role.

Purpose: This chapter explores the two major schemes applicable to skill development in India: Skill Acquisition and Knowledge Awareness for Livelihood Promotion (SANKALP) and Pradhan Mantri Kaushal Vikas Yojana (PMKVY).

Need for the Study: The primary objective of this research is to check the role of these schemes in enhancing the skills of socio-economically stressed community members for their livelihoods. The secondary aim is to analyse the outcomes of these schemes through a qualitative inquiry.

Methodology: A survey was conducted, and the data was collected from trainees of the skill development programmes. Based on the responses, a qualitative content analysis was performed, which showed that most trainees have the thirst and urge to enhance their life skills for a minimalistic livelihood.

Findings: The study concluded that though there are many schemes, only PMKVY is active. They focus on more than just youth communities. Instead, they consider individuals in different age categories.

Practical Implications: The Government of India (GOI) is progressing towards a healthy economy to compete with other countries. For this mission to be achieved, skill and labour development is paramount. Appropriate training must be provided and administrated through government schemes.

The purpose of this paper is to implement a closed loop regulated bidirectional DC to DC converter for an application in the electric power system of more electric aircraft. To provide a consistent power supply to all of the electronic loads in an aircraft at the desired voltage level, good efficiency and desired transient and steady-state response, a smart and affordable DC to DC converter architecture in closed loop mode is being designed and implemented.

The aircraft electric power system (EPS) uses a bidirectional half-bridge DC to DC converter to facilitate the electric power flow from the primary power source – an AC generator installed on the aircraft engine’s shaft – to the load as well as from the secondary power source – a lithium ion battery – to the load. Rechargeable lithium ion batteries are used because they allow the primary power source to continue recharging them whenever the aircraft engine is running smoothly and because, in the event that the aircraft engine becomes overloaded during takeoff or turbulence, the charged secondary power source can step in and supply the load.

A novel nonsingular terminal sliding mode voltage controller based on exponential reaching law is used to keep the load voltage constant under any of the aforementioned circumstances, and its performance is contrasted with a tuned PI controller on the basis of their respective transient and steady-state responses. The former gives a faster and better transient and steady-state response as compared to the latter.

This research gives a novel control scheme for incorporating an auxiliary power source, i.e. rechargeable battery, in more electric aircraft EPS. The battery is so implemented that it can get regeneratively charged when primary power supply is capable of handling an additional load, i.e. the battery. The charging and discharging of the battery is carried out in closed loop mode to ensure constant battery terminal voltage, constant battery current and constant load voltage as per the requirement. A novel sliding mode controller is used to improve transient and steady-state response of the system.

COVID-19 has affected the economies adversely from all sides. The sudden halt in production has impacted both the supply and demand sides. It calls for analysis to quantify the impact of the reduction in economic activity on the economy-wide variables so that appropriate steps can be taken. This study aims to evaluate the sensitivity of various sectors of the Indian economy to this dual shock.

The eight-sector open economy general equilibrium Global Trade Analysis Project (GTAP) model has been simulated to evaluate the sector-specific effects of a fall in economic activity due to COVID-19. This model uses an economy-wide accounting framework to quantify the impact of a shock on the given equilibrium economy and report the post-simulation new equilibrium values.

The empirical results state that welfare for the Indian economy falls to the tune of 7.70% due to output shock. Because of demand–supply linkages, it also impacts the inter- and intra-industry flows, demand for factors of production and imports. There is a momentous fall in the demand for factor endowments from all sectors. Among those, the trade-hotel-transport and manufacturing sectors are in the first two positions from the top. The study recommends an immediate revival of the manufacturing and trade-hotel-transport sectors to get the Indian economy back on track.

The present study has modified the existing GTAP model accounting framework through unemployment and output closures to account for the impact of change in sectoral output due to COVID-19 on the level of employment and other macroeconomic variables.

Social sciences have discussed the host–guest relation from many theoretical lenses and perspectives. Violence as well as local crime has been studied as one of the major risks concerning tourism security. Anyway, less attention was given to homeless people and their interaction with foreign or local tourists. The purpose of this paper is oriented to explain how globalization has winners and losers, in which case, as noted, thousands of persons are excluded from the formal labor marketplace or the economic system year by year.

This is a conceptual paper that discusses critically not only the recent advances of sociology in urban tourism but also the connection between homeless people and tourists.

There is an urban underclass formed by those who have been excluded from the economic system. What is more important, such an underclass situates nearby luxury hotels and tourist destinations creating serious contradictions or zones of disputes. These contradictions have been approached by different sociologists since the turn of the 20th century.

The question of sustainability, as well as the idea of liveable cities, and the efficient organization of the city, have occupied a central position in the academic debate, above all after the COVID-19 pandemic. In the present paper, the authors put in dialogue the contributions of Marc Auge with Zyggy Bauman toward a new understanding of this postmodern phenomenon.

Based on the metaphor of vagabonds and tourists, we give a snapshot of the problem of homelessness in Buenos Aires city and its effects on the tourism industry. Unlike other English-speaking countries where the cities are actively organized by the state, Buenos Aires city lacks a planned program to regulate and relocate homeless people. They dwell in nonplaces nearby tourists sleeping in the streets near luxury hotels (but for sure escaping any planning or governmental control).

In recent times, there has been a growing interest in buoyancy-induced heat transfer within confined enclosures due to its frequent occurrence in heat transfer processes across diverse engineering disciplines, including electronic cooling, solar technologies, nuclear reactor systems, heat exchangers and energy storage systems. Moreover, the reduction of entropy generation holds significant importance in engineering applications, as it contributes to enhancing thermal system performance. This study, a numerical investigation, aims to analyze entropy generation and natural convection flow in an inclined square enclosure filled with Ag–MgO/water and Ag–TiO2/water hybrid nanofluids under the influence of a magnetic field. The enclosure features heated slits along its bottom and left walls. Following the Boussinesq approximation, the convective flow arises from a horizontal temperature difference between the partially heated walls and the cold right wall.

The governing equations for laminar unsteady natural convection flow in a Newtonian, incompressible mixture is solved using a Marker-and-Cell-based finite difference method within a customized MATLAB code. The hybrid nanofluid’s effective thermal conductivity and viscosity are determined using spherical nanoparticle correlations.

The numerical investigations cover various parameters, including nanoparticle volume concentration, Hartmann number, Rayleigh number, heat source/sink effects and inclination angle. As the Hartmann and Rayleigh numbers increase, there is a significant enhancement in entropy generation. The average Nusselt number experiences a substantial increase at extremely high values of the Rayleigh number and inclination.

This numerical investigation explores advanced applications involving various combinations of influential parameters, different nanoparticles, enclosure inclinations and improved designs. The goal is to control fluid flow and enhance heat transfer rates to meet the demands of the Fourth Industrial Revolution.

In a 90° tilted enclosure, the addition of 5% hybrid nanoparticles to the base fluid resulted in a 17.139% increase in the heat transfer rate for Ag–MgO nanoparticles and a 16.4185% increase for Ag–TiO2 nanoparticles compared to the base fluid. It is observed that a 5% nanoparticle volume fraction results in an increased heat transfer rate, influenced by variations in both the Darcy and Rayleigh numbers. The study demonstrates that the Ag–MgO hybrid nanofluid exhibits superior heat transfer and fluid transport performance compared to the Ag–TiO2 hybrid nanofluid. The simulations pertain to the use of hybrid magnetic nanofluids in fuel cells, solar cavity receivers and the processing of electromagnetic nanomaterials in enclosed environments.

Taking into consideration the current human need for agricultural produce such as rice that requires water for growth, the optimal consumption of this valuable liquid is important. Unfortunately, the traditional use of water by humans for agricultural purposes contradicts the concept of optimal consumption. Therefore, designing and implementing a mechanized irrigation system is of the highest importance. This system includes hardware equipment such as liquid altimeter sensors, valves and pumps which have a failure phenomenon as an integral part, causing faults in the system. Naturally, these faults occur at probable time intervals, and the probability function with exponential distribution is used to simulate this interval. Thus, before the implementation of such high-cost systems, its evaluation is essential during the design phase.

The proposed approach included two main steps: offline and online. The offline phase included the simulation of the studied system (i.e. the irrigation system of paddy fields) and the acquisition of a data set for training machine learning algorithms such as decision trees to detect, locate (classification) and evaluate faults. In the online phase, C5.0 decision trees trained in the offline phase were used on a stream of data generated by the system.

The proposed approach is a comprehensive online component-oriented method, which is a combination of supervised machine learning methods to investigate system faults. Each of these methods is considered a component determined by the dimensions and complexity of the case study (to discover, classify and evaluate fault tolerance). These components are placed together in the form of a process framework so that the appropriate method for each component is obtained based on comparison with other machine learning methods. As a result, depending on the conditions under study, the most efficient method is selected in the components. Before the system implementation phase, its reliability is checked by evaluating the predicted faults (in the system design phase). Therefore, this approach avoids the construction of a high-risk system. Compared to existing methods, the proposed approach is more comprehensive and has greater flexibility.

By expanding the dimensions of the problem, the model verification space grows exponentially using automata.

Unlike the existing methods that only examine one or two aspects of fault analysis such as fault detection, classification and fault-tolerance evaluation, this paper proposes a comprehensive process-oriented approach that investigates all three aspects of fault analysis concurrently.

In light of the key role attributed to the board of directors as a monitoring tool to constrain earnings management practices, this study aims to examine the effect of some board attributes on accrual-based earnings management and real earnings management in the Middle Eastern and North African (MENA) context, whose institutional, economic and legal environment is markedly different from that of most organization for economic cooperation and development countries.

The authors selected a sample of 161 nonfinancial companies from nine MENA countries between 2014 and 2021 (corresponding to an unbalanced data panel of 486 observations). The authors used the generalized least squares regression test to examine the relationship between board attributes and earnings management.

The authors found that three board attributes (size, independence and gender diversity) have no effect on both types of earnings management practices, while CEO duality has no effect on accrual-based earnings management but has a significant and negative effect on real earnings management. Overall, the results suggest that most board attributes do not play a crucial role in reducing earnings management.

The results provide valuable insights into the universal role of corporate governance mechanisms and raise questions about the role of the board of directors in improving reporting quality in the MENA context.

Regulators should adapt corporate governance mechanisms to the characteristics of the institutional context in which they are inserted.

To the best of the authors’ knowledge, this study is the first to examine the effect of various board characteristics on both types of earnings management practices in the MENA context. It also provides the first empirical evidence of the relationship between board gender diversity and earnings management in the MENA region.

This paper aims to examine the relationship between organizational learning (OL) and technology through the lens of strategic factors and to ascertain future research directions.

The systematic literature review method was applied in three stages to the 76 articles obtained from Scopus, Web of Science, Google Scholar and EBSCO databases.

This research revealed the evolution of the role of OL in innovation, performance, knowledge management and technological adoption and showcases a detailed conceptual model relating technology outcomes (technological innovation and capabilities) to OL outcomes (technology absorptive capacity, technological proactivity, as well as information technology [IT] and organization process alignment).

This review includes articles mainly in English and excludes conference proceedings.

This research attempts to guide managers and policymakers to foster an organizational culture conducive to technological adoption and OL. It helps organizations develop strategies for new product development, including strategic alliances and strategic leadership.

This review formalizes the linkages between technological absorptive capacity, technological proactivity and IT with technological innovation and capabilities. It identifies research gaps and elucidates future research directions.