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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.

This study aims to develop an experimentally validated three-dimensional numerical model for predicting different flow patterns produced with a gas dynamic virtual nozzle (GDVN).

The physical model is posed in the mixture formulation and copes with the unsteady, incompressible, isothermal, Newtonian, low turbulent two-phase flow. The computational fluid dynamics numerical solution is based on the half-space finite volume discretisation. The geo-reconstruct volume-of-fluid scheme tracks the interphase boundary between the gas and the liquid. To ensure numerical stability in the transition regime and adequately account for turbulent behaviour, the k-ω shear stress transport turbulence model is used. The model is validated by comparison with the experimental measurements on a vertical, downward-positioned GDVN configuration. Three different combinations of air and water volumetric flow rates have been solved numerically in the range of Reynolds numbers for airflow 1,009–2,596 and water 61–133, respectively, at Weber numbers 1.2–6.2.

The half-space symmetry allows the numerical reconstruction of the dripping, jetting and indication of the whipping mode. The kinetic energy transfer from the gas to the liquid is analysed, and locations with locally increased gas kinetic energy are observed. The calculated jet shapes reasonably well match the experimentally obtained high-speed camera videos.

The model is used for the virtual studies of new GDVN nozzle designs and optimisation of their operation.

To the best of the authors’ knowledge, the developed model numerically reconstructs all three GDVN flow regimes for the first time.

For metal additive manufacturing, metallic powders are usually produced by vacuum induction gas atomization (VIGA) through the breakup of liquid metal into tiny droplets by gas jets. VIGA is considered a cost-effective technique to prepare feedstock. In VIGA, the quality and the morphology of the produced particles are mainly controlled by the gas pressure used during powder production, keeping the setup configuration constant.

In VIGA process for metallic additive manufacturing feedstock preparation, the quality and morphology of the powder particles are mainly controlled by the gas pressure used during powder production.

In this study, Inconel-625 feedstock was produced using a supersonic nozzle in a close-coupled gas atomization apparatus. Powder size distribution (PSD) was studied by varying the gas pressure.

The nonmonotonic but deterministic relationships were observed between gas pressure and PSD. It was found that the maximum 15–45 µm percentage PSD, equivalent to 84%, was achieved at 29 bar Argon gas pressure, which is suitable for the LPBF process. Following on, the produced powder particles were used to print tensile test specimens via LPBF along XY- and ZX-orientations by using laser power = 475 W, laser scanning speed = 800 mm/s, powder layer thickness = 50 µm and hatch distance = 100 µm. The yield and tensile strengths were 9.45% and 13% higher than the ZX direction, while the samples printed in ZX direction resulted in 26.79% more elongation compared to XY-orientation.

The pervasive impact of the COVID-19 virus on the food services sector in India has created conditions for fundamentally altering the structure of the industry. This paper offers a nuanced evaluation of the transfiguration of the market, explaining descriptive views supported by numerous secondary data sources.

This is a self-driven study grounded in secondary data. Qualitative and quantitative assessments are assimilated from credible market research reports of multiple agencies in the Indian context, as well as news developments during the pandemic period.

Digitally pivoted platforms such as cloud kitchens and delivery aggregators will eclipse all other formats due to the potential long-term prevalence of the COVID-19 virus. These formats would rise to a dominant position in the Indian food services sector in the coming decade.

This study is entirely driven by secondary data due to the inherent difficulties of collecting sizeable and good quality primary data as a result of the lengthy and stringent lockdowns imposed across India. Future studies should consider collecting consumer responses to get a better picture of changing dining habits in the post-pandemic scenario.

The dynamic and evolving food services in India, catalyzed by the Internet and digital technologies will help academicians study the long-term implications of this change, and how it would impact society at large. The paper provides a rich body of contemporary data and analysis in the food services sphere.

The COVID-19 pandemic and its long-term persistence would dramatically alter food service consumption across India. This will not only change how the industry is structured, but will reshape how food is consumed into the future.

The study is a holistic examination of the relationship between the coronavirus pandemic and the food services industry in India. The macro perspectives aided by news coverage and industry research would help generate potential research questions on its own merits.

Loneliness is widely prevalent in modern society. Despite the growth in studies, very limited studies so far have attempted to systematically review the literature. This study aims to consolidate the antecedents of loneliness by reviewing the literature.

The systematic literature review method is adopted to identify the antecedents. Full texts of each article were taken for analysis which was published from 2002 to 2022. Multiple databases were examined and total of 60 articles were included for systematic literature review.

The study presents the descriptive analysis of the articles. Also, the paper thematically presents the key antecedents of loneliness in three themes (a) Loss of love, (b) Individual cognitive and personal factors and (c) Childhood experiences and parenting practices. The study also highlights the moderating effect of demographic factors and lifestyle changes.

The current study is the first systematic literature review to present the antecedents of loneliness. The study contributes by offering an enhanced understanding of loneliness. Also, the study presents contemporary understanding of loneliness and proposes a conceptual framework. The findings are useful to academicians as well as policymakers.

The purpose of this study is to explore decision-making of elementary teachers (n = 5) specific to US/American history content and curricular resources. More specifically for this study, the author asks the following broad research question: When presented with a collection of social studies instructional resources, how do elementary teachers describe the choices they do make/may make?

In this comparative case study, fifth-grade teachers were interviewed using verbal protocol methodology, they discussed their curriculum, teaching and instructional decisions as each was presented with history/social studies resources associated with newly adopted state standards.

Findings indicate these elementary teachers have professional freedom to make instructional decisions in the ways they interpreted the standards, design instruction and select materials for social studies.

This study contributes to and extends the research in elementary social studies. Teachers' voices and decisions are presented as intellectual and pedagogical actions associated with teaching elementary school social studies.

The construction industry (CI) is a major contributor to the gross domestic product of most economies. Yet, the industry is characterized by poorly performing projects, plagued with cost overruns, delays, with a relatively high-risk nature and marginal returns. Given that construction projects are financially dynamic, relying on highly fluctuating working capital and cash-flow requirements, there is an imperative need to understand the working capital management (WCM) of the CI. This study aims to review the extant literature on WCM in the CI to present a contemporary positional paper and engender a wider polemic debate on this crucial phenomenon.

A systematic literature review methodology is used, using Google Scholar as the literature database.

Despite the importance of this research theme, only 16 publications dedicated to the topic of WCM in the CI are identified. This is an important finding in itself and is indicative of hitherto scant research conducted. Other observations include the lack of experts examining the field, with no authors exploring the theme more than once. Subthemes of WCM are also scarce, with only the topic of the relationship between “WCM and profitability” been revisited and refined in literature; all other topics being cursory.

This study is among pioneering papers in developing economies that have taken stock of WCM in the CI. As a result, the conclusion of this paper is to call out the paucity of research in WCM and set a broad agenda for future research.

This study aims to investigate if engineered compression variations using moisture-responsive knitted fabric design can improve breast support in seamless knitted sports bras.

An experimental approach was used to integrate a novel moisture-responsive fabric panel into a seamless knitted bra, and the resulting compression variability in dry versus wet conditions were compared with those of a control bra. Air permeability and elongation testing of between breasts fabric panels was conducted in dry and wet conditions, followed by three-dimensional body scanning of eight human participants wearing the two bras in similar conditions. Questionnaires were used to evaluate perceived comfort and breast support of both bras in both conditions.

Air permeability test results showed that the novel panel had the highest variance between dry and wet conditions, confirming its moisture-responsive design, and increased its elongation coefficient in both wale and course directions in wet condition. There were significant main effects of bra type and body location on breast compression measurements. Breast circumferences in the novel bra were significantly larger than in the control bra condition. The significant two-way interaction between bra type and moisture condition showed that the control bra lost compressive power in wet condition, whereas the novel bra became more compressive when wet. Changes in compression were confirmed by participants’ perception of tighter straps and drier breast comfort.

These findings add to the limited scientific knowledge of moisture adaptive bra design using engineered knitted fabrics via advanced manufacturing technologies, with possible applications beyond sports bras, such as bras for breast surgery recovering patients.

This paper aims to fill gap in the literature and explore policy options for resolving the problems of accountability by framing three research questions. The research questions are (i) whether certain elements of Scott’s (2014) institutional pillars attenuate (accentuate) corporate and public accountability; (ii) whether the presence of ruling party-affiliated enterprises (RPAEs) create an increase (decrease) in the degree of corporate (public) accountability; and (iii) whether there is a particular form of ownership change that transforms RPAEs into public investment companies.

Using a qualitative research methodology that involves term frequency and thematic analysis of publicly available textual information, the paper examines Mechkova et al.’s (2019 forms of government accountability. The paper analyzes the gaps between the de jure and de facto accountability using the institutional pillars framework.

The findings of the paper are three. First, there are gaps between de jure and de facto in all three (vertical, horizontal and diagonal) forms of government (public) accountability. Second, the study finds that more than three fourth of the parties that contested the June 2021 election did have regional focus. They did not advocate for accountability. Third, Ethiopia’s RPAEs are unique. They have regional focus and are characterized by severe forms of agency and information asymmetry problems.

The main limitation of the paper is its exploratory nature. Extending this research by using cross-country data could provide a more complete picture of the link between corporate (public) accountability and a country’s institutional pillars.

Academic research documents that instilling modern corporate (public) governance standards in the Sub Sahara Africa (SSA) region has shown mixed results. The analysis made in this paper is likely to inform researchers and policymakers about the type of change that leads to better corporate (and public) accountability outcomes.

The institutional change proposed in the paper is likely to advance the public interest by mitigating agency and information asymmetry problems and enhancing government accountability. The changes make the enterprises investable, save scarce jobs, enhance diversity and put the assets in RPAEs to better use.

To the best of the authors’ knowledge, this is the first paper that uses the institutional pillars analytical framework to examine an SSA country's corporate (public) accountability problem. It demonstrates that accountability is a domestic and a (novel) traveling theory. The paper identifies the complexity of resolving the interlock between political institutions and business enterprises. It theorizes that it is impossible to instill modern corporate (public) accountability standards without changing regulatory, normative and cultural cognitive pillars of institutions. The paper contributes to the change management and public interest literature.

This study which is positioned in the ambit of control research investigates the impact of ex ante contractual completeness on opportunistic behaviors and ex post transaction costs, while assessing how these affect relationship termination intention. This study aims to examine alternative attractiveness as a necessary moderator of the nexus between transaction cost and relationship termination intention.

Data gathered from 211 companies in South Korea that have installed and run outsourced vending machines are analyzed and used to validate the study’s theoretical and empirical contributions.

The findings, which rely only on data from companies that outsource and those that run outsourced vending machines, show that contractual completeness negatively affects both active and passive opportunism. The study also discovers that active opportunism positively affects both bargaining costs and monitoring costs, whereas passive opportunism has a positive and direct effect on maladaptation costs but a negative effect on monitoring costs. It further finds that both bargaining and maladaptation costs have positive and direct effects on relationship termination intention, while monitoring costs have a negative effect on the same. Furthermore, it is observed that alternative attractiveness moderates the relationships between bargaining costs and relationship termination intention, as well as maladaptation costs and relationship termination intention.

This study demonstrates that contractual completeness can serve as an important ex ante control mechanism, whereas the two types of opportunism can raise transaction costs. Furthermore, alternative attractiveness is identified as a driver of the impact of transaction costs on relationship termination intention.

A key point of the departure of this study is that it examines the moderating role of alternative attractiveness in the relationship between transaction cost and relationship termination intention. The paper also advances the control literature by emphasizing the critical role that contractual completeness plays in reducing the occurrence of (both active and passive) opportunism in business relationships (especially companies that outsource).