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1 – 10 of 339
Article
Publication date: 5 September 2023

Nikesh Chowrasia, Subramani S.N., Harish Pothukuchi and B.S.V. Patnaik

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…

Abstract

Purpose

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.

Design/methodology/approach

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.

Findings

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.

Practical implications

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.

Originality/value

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.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 33 no. 12
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 1 April 1988

Ronald H. Fritze

The Dictionary of National Biography (or DNB as it is commonly called and as it will be referred to in this paper) is a classic. Depending on whether a library owns an original…

Abstract

The Dictionary of National Biography (or DNB as it is commonly called and as it will be referred to in this paper) is a classic. Depending on whether a library owns an original edition published by Smith, Elder and Company or a reprint edition published by Oxford University Press, sixty‐three brown volumes or twenty‐two blue volumes and supplements loom bulkily from the shelves. It would be an odd, ill‐trained reference librarian, historian, or scholar of English literature who has never heard of the DNB, let alone used and perused it. But mere bulk does not explain the lasting fame and staying power of this reference work, whose first volume appeared in January 1885 over a century ago.

Details

Reference Services Review, vol. 16 no. 4
Type: Research Article
ISSN: 0090-7324

Article
Publication date: 1 April 1968

If I understand Mr Gomperts correctly, he is referring, in the ‘law of constant citation’, to citing articles, and to the number of references (citations) contained therein.

Abstract

If I understand Mr Gomperts correctly, he is referring, in the ‘law of constant citation’, to citing articles, and to the number of references (citations) contained therein.

Details

Journal of Documentation, vol. 24 no. 4
Type: Research Article
ISSN: 0022-0418

Article
Publication date: 15 June 2010

Reinhard Altenhöner and Tobias Steinke

This paper intends to describe activities of the Deutsche Nationalbibliothek (DNB, the German National Library) in digital preservation. Special attention is to be given to the…

1195

Abstract

Purpose

This paper intends to describe activities of the Deutsche Nationalbibliothek (DNB, the German National Library) in digital preservation. Special attention is to be given to the long‐term preservation project kopal, but prior developments, strategic implications and future scenarios will be addressed as well.

Design/methodology/approach

The paper is a narrative of the findings, that also describes the technical specification of kopal.

Findings

The current status of kopal development is presented, added by some remarks on potentials for further activities with regard to a digital preservation infrastructure.

Originality/value

Kopal has been presented in other publications. This paper describes the “strategic” value and impact of the solution, added by insights for future development.

Details

Library Hi Tech, vol. 28 no. 2
Type: Research Article
ISSN: 0737-8831

Keywords

Article
Publication date: 15 November 2018

Paula Dootson, Kim A. Johnston, Ian Lings and Amanda Beatson

Deviant consumer behavior (DCB) has serious negative effects on organizations, employees and other customers. While research to date has largely focused on understanding why…

1293

Abstract

Purpose

Deviant consumer behavior (DCB) has serious negative effects on organizations, employees and other customers. While research to date has largely focused on understanding why consumers engage in deviant behaviors, less focus has been placed on exploring how to deter them. This paper aims to shift the conversation from research exploring why consumers engage in deviant behaviors to understanding how DCB could be deterred.

Design/methodology/approach

In this conceptual paper, a research agenda of deterrence tactics is provided with associated propositions to guide future research in the field of DCB.

Findings

A deterrence–neutralization–behavior (DNB) framework is proposed to underpin the seven deterrence tactics outlined in this research agenda. The DNB framework illustrates the positive relationship between neutralization techniques and engagement in DCB, because the techniques reduce the level of cognitive dissonance associated with performing a deviant act beyond an individual’s deviance threshold. The framework adds a new proposed moderating role of deterrence tactics. Deterrence tactics are mechanisms that will reintroduce cognitive dissonance, previously reduced through a neutralization technique, by presenting the consumer with a competing piece of information that challenges their attitudes, beliefs or behavior. Therefore, the authors propose that certain deterrence tactics could diminish the positive effect of different neutralization techniques on DCB if the tactics challenge the justifications consumers are using to excuse their actions – subsequently reintroducing cognitive dissonance.

Practical implications

Practically, this paper is the next step in an effort to provide evidence-based solutions for managers seeking to reduce the negative impact that deviance has on the organization.

Originality/value

To date, research has focused on understanding why DCB occurs with limited attention on how it can be deterred. The value in this paper is in proposing a series of deterrence tactics that are theoretically matched to established antecedents and neutralization techniques associated with DCB. Overall, this paper provides a future research agenda with propositions to build knowledge on effective deterrence tactics for curbing instances of DCB.

Details

Journal of Consumer Marketing, vol. 35 no. 6
Type: Research Article
ISSN: 0736-3761

Keywords

Open Access
Article
Publication date: 21 January 2020

Martin Jullum, Anders Løland, Ragnar Bang Huseby, Geir Ånonsen and Johannes Lorentzen

The purpose of this paper is to develop, describe and validate a machine learning model for prioritising which financial transactions should be manually investigated for potential…

36857

Abstract

Purpose

The purpose of this paper is to develop, describe and validate a machine learning model for prioritising which financial transactions should be manually investigated for potential money laundering. The model is applied to a large data set from Norway’s largest bank, DNB.

Design/methodology/approach

A supervised machine learning model is trained by using three types of historic data: “normal” legal transactions; those flagged as suspicious by the bank’s internal alert system; and potential money laundering cases reported to the authorities. The model is trained to predict the probability that a new transaction should be reported, using information such as background information about the sender/receiver, their earlier behaviour and their transaction history.

Findings

The paper demonstrates that the common approach of not using non-reported alerts (i.e. transactions that are investigated but not reported) in the training of the model can lead to sub-optimal results. The same applies to the use of normal (un-investigated) transactions. Our developed method outperforms the bank’s current approach in terms of a fair measure of performance.

Originality/value

This research study is one of very few published anti-money laundering (AML) models for suspicious transactions that have been applied to a realistically sized data set. The paper also presents a new performance measure specifically tailored to compare the proposed method to the bank’s existing AML system.

Details

Journal of Money Laundering Control, vol. 23 no. 1
Type: Research Article
ISSN: 1368-5201

Keywords

Article
Publication date: 16 September 2013

John Kendall

– -- The purpose of this paper is to provide an overview of the Oxford Dictionary of National Biography including a brief history but with the focus on its electronic format.

7526

Abstract

Purpose

-- The purpose of this paper is to provide an overview of the Oxford Dictionary of National Biography including a brief history but with the focus on its electronic format.

Design/methodology/approach

-- A historical account of the forerunner publication is provided, followed by consideration of the content of the new electronic version in contrast to that provided in the earlier print editions. There is also consideration of the structure of the work, with a look at the “added value” features provided. Illustrative examples are used throughout.

Findings

-- The Oxford Dictionary of National Biography continues to provide comprehensive coverage of notable British figures and is easy to navigate and use in its electronic version. Most significantly, it remains an essential resource for libraries, especially in the UK.

Originality/value

-- There have been many reviews of the Oxford Dictionary of National Biography, but this is one of the few to have been published in recent years providing an overview with a focus on the advantages of the electronic version. For information professionals it offers a useful summary of the main features of this resource and a reminder of its continuing value as a biographical information tool.

Details

Reference Reviews, vol. 27 no. 7
Type: Research Article
ISSN: 0950-4125

Keywords

Abstract

Details

Investment Traps Exposed
Type: Book
ISBN: 978-1-78714-253-4

Case study
Publication date: 16 April 2020

Bei Zeng, Andreas Johannesen and Xin Fang

This study aims to provide students an opportunity to analyze the financial performance of a publicly listed real estate company and estimate its instinct value by applying…

Abstract

Purpose

This study aims to provide students an opportunity to analyze the financial performance of a publicly listed real estate company and estimate its instinct value by applying appropriate financial models and approaches.

Theoretical basis

Three major valuation models/approaches generated by financial theory and practice to estimate the intrinsic value of a security: discounting cash-flows valuation (DCF and NPV) – valuation through adjusted net asset and liquidation value (NAV) – relative valuation through price and value multiples (valuation multiple analysis and precedent transactions analysis). Wholly owned subsidiaries versus and joint venture ones.

Research methodology

Analyze financial information of all segments in a multiple-business firm, and apply suitable financial models and approaches among net asset value model (NAV), discounted cash flow (DCF) or net present value (NPV) model, valuation multiple analysis and precedent transactions analysis to estimate the intrinsic value of the whole firm.

Case overview/synopsis

This decision-based case allows students to explore the business valuation process for a public listed real estate company, Alexander & Baldwin, Inc. (NYSE: ALEX). Based on financial statements analysis and forward-looking financial expectation on ALEX, this case elevates students' understanding and practice of valuating this multiple-business firms by applying appropriate financial models and approaches among NAV, DCF or NPV, valuation multiple analysis and precedent transactions analysis and enable students to make their investment decisions of buying, holding or selling the company’s stocks.

Complexity academic level

This case is most appropriate for graduate courses such as corporate finance, investments, personal finance, real estate finance and financial markets and institutes.

Article
Publication date: 28 March 2024

Anna Young-Ferris, Arunima Malik, Victoria Calderbank and Jubin Jacob-John

Avoided emissions refer to greenhouse gas emission reductions that are a result of using a product or are emission removals due to a decision or an action. Although there is no…

Abstract

Purpose

Avoided emissions refer to greenhouse gas emission reductions that are a result of using a product or are emission removals due to a decision or an action. Although there is no uniform standard for calculating avoided emissions, market actors have started referring to avoided emissions as “Scope 4” emissions. By default, making a claim about Scope 4 emissions gives an appearance that this Scope of emissions is a natural extension of the existing and accepted Scope-based emissions accounting framework. The purpose of this study is to explore the implications of this assumed legitimacy.

Design/methodology/approach

Via a desktop review and interviews, we analyse extant Scope 4 company reporting, associated accounting methodologies and the practical implications of Scope 4 claims.

Findings

Upon examination of Scope 4 emissions and their relationship with Scopes 1, 2 and 3 emissions, we highlight a dynamic and interdependent relationship between quantification, commensuration and standardization in emissions accounting. We find that extant Scope 4 assessments do not fit the established framework for Scope-based emissions accounting. In line with literature on the territorializing nature of accounting, we call for caution about Scope 4 claims that are a distraction from the critical work of reducing absolute emissions.

Originality/value

We examine the implications of assumed alignment and borrowed legitimacy of Scope 4 with Scope-based accounting because Scope 4 is not an actual Scope, but a claim to a Scope. This is as an act of accounting territorialization.

Details

Accounting, Auditing & Accountability Journal, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0951-3574

Keywords

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