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The purpose of this paper is to develop, apply and validate a mesh-free graph theory–based approach for rapid thermal modeling of the directed energy deposition (DED) additive manufacturing (AM) process.

In this study, the authors develop a novel mesh-free graph theory–based approach to predict the thermal history of the DED process. Subsequently, the authors validated the graph theory predicted temperature trends using experimental temperature data for DED of titanium alloy parts (Ti-6Al-4V). Temperature trends were tracked by embedding thermocouples in the substrate. The DED process was simulated using the graph theory approach, and the thermal history predictions were validated based on the data from the thermocouples.

The temperature trends predicted by the graph theory approach have mean absolute percentage error of approximately 11% and root mean square error of 23°C when compared to the experimental data. Moreover, the graph theory simulation was obtained within 4 min using desktop computing resources, which is less than the build time of 25 min. By comparison, a finite element–based model required 136 min to converge to similar level of error.

This study uses data from fixed thermocouples when printing thin-wall DED parts. In the future, the authors will incorporate infrared thermal camera data from large parts.

The DED process is particularly valuable for near-net shape manufacturing, repair and remanufacturing applications. However, DED parts are often afflicted with flaws, such as cracking and distortion. In DED, flaw formation is largely governed by the intensity and spatial distribution of heat in the part during the process, often referred to as the thermal history. Accordingly, fast and accurate thermal models to predict the thermal history are necessary to understand and preclude flaw formation.

This paper presents a new mesh-free computational thermal modeling approach based on graph theory (network science) and applies it to DED. The approach eschews the tedious and computationally demanding meshing aspect of finite element modeling and allows rapid simulation of the thermal history in additive manufacturing. Although the graph theory has been applied to thermal modeling of laser powder bed fusion (LPBF), there are distinct phenomenological differences between DED and LPBF that necessitate substantial modifications to the graph theory approach.

Grounded in experience of co-organizing a two-day photography-based workshop in Paris, this paper explores how photo-dialogues can facilitate anti-racist pedagogy and generative discussions about how race and racism function in marketplace contexts.

This paper draws on the authors' involvement in a cross-national and cross-disciplinary team of scholars who worked with local community stakeholders—including activists, artists and practitioners—to discuss, theorize and photo-document issues regarding race and racism in the Parisian marketplace.

This paper contributes to the literature on visual culture studies and critical race studies as it demonstrates the potentials of photography combined with dialogue to challenge the White supremacy over archiving and visuality in the context of urban spaces. This new methodology is an opportunity to reflect on archetypes of visuality that depart from the traditional Parisian flâneur to be consistent with and reinforce anti-racist stances.

Photography and visual methods often play peripheral roles in anti-racist education across various disciplines and research areas, including critical marketplace studies. This paper expands understanding of the potentials of using photographic methods as part of critical and anti-racist work related to racial and racist dynamics, including issues regarding power, White supremacy and public space. It outlines the use of photographic dialogues in a context (Paris, France) where discussion of race is regularly societally discouraged. Thus, this work shifts the focus away from decontextualized research that regards race as an object, to specifically foreground understandings of racialized experiences and how the photographic gaze produces and is produced by racialized viewers.

We document the emergence of the Lead Independent Director (LID) board role in a sample of U.S. firms from 1999–2015. We find that firms that adopt an LID board role are larger and have more independent boards, higher institutional investor holdings, and an NYSE listing. Firms with greater anticipated benefits from monitoring also adopt an LID role, e.g., firms with dual CEO-Chairman, with more takeover defense mechanisms, and with higher cash holdings. Using an event study methodology, we find that investors respond positively to the adoption of an LID board role. Lastly, using instrumental variables to address endogeneity in the LID board role, we find that firms with an LID are more likely to terminate poorly performing CEOs. Taken as a whole, these results suggest that the LID board role enhances firm value and improves the quality of corporate governance.

The purpose of this paper is to integrate the findings of articles appearing in European Journal of Marketing’s special section on covariance-based versus composite-based structural equations modeling (SEM).

This is an editorial which uses literature review to draw conclusions regarding areas of agreement, areas for further research, and changing the discussion around composite-based SEM methods.

There are now four new areas of agreement regarding composite-based SEM. Researchers should adopt a toolbox approach to their methods and know the strengths and weaknesses of the research tools in their toolbox. Partial least squares (PLS) SEM and covariance-based SEM are not substitutes, and it is inappropriate to use the language of confirmatory factor analysis (CFA) in reporting measurement estimates from PLS SEM. Measurement matters and researchers need to devote effort to using reliable and valid multi-item measures in their investigations.

This postscript article outlines recommendations for authors, reviewers and editors regarding the analysis of data and reporting of results using structural equations models.

The purpose of this study is to examine the impact of a recent innovation in the uranium market, the Global X Uranium Exchange-Traded Fund (URA), on the trading characteristics of constituent and non-constituent stocks.

The authors analyse bid-ask spread measures, relative effective spreads and adverse selection costs to assess changes in information asymmetry among uranium stocks. The authors also study abnormal returns to assess the impact of URA on the market.

Over a three-month period, following the introduction of URA, the authors find uranium stocks display decreased bid-ask spread measures, driven by reductions in information asymmetry. Relative effective spreads decrease by 36% after the introduction of URA, and adverse selection costs decline by 24% over the same period. Uranium stocks experience a significant positive abnormal return of 5.0% the day after the introduction of URA with subsequent price reversals. These suggest that the introduction of URA prompted uninformed traders to rebalance portfolios and migrate to the less information-sensitive Exchange-Traded Fund (ETF), causing temporary deviations in trading characteristics.

The authors demonstrate that the introduction of new financial securities to the market can have a significant impact on the trading characteristics of related equities. As URA is the only ETF in the uranium sector, the authors thereby avoid the influence of multiple ETFs that may have impacted previous studies.

This paper aims to closely examine the features of an urban community-based learning program to highlight the synergy between its educational technology, literate practices and social justice ethos that impact youths’ learning and documentary filmmaking. This examination of a learning setting illuminates the “what is possible” and “how it comes to be possible” (Gomez et al., 2014, p. 10), illustrating possibilities for youths’ tech-mediated literacies to facilitate, support and extend engagement in social justice.

Grounded in the theoretical and analytical concept of activity theory, this study uses qualitative methods and activity systems analysis. Observations are the primary data source coupled with a detailed activity analysis supported by artifacts, images and interviews. Program participants included 12 youth, 2 youth mentors, 1 adult coordinator and 1 adult facilitator.

Findings illustrate that all subjects (participants) in the program co-created and shaped the activity system’s object (or purpose). Analyses also reveal the ways in which the program enables and empowers youth through its development of participatory literacy practices that “can facilitate learning, empowerment, and civic action” (Jenkins et al., 2016).

Overall, this study is a contribution to the field as it responds to the need for close examinations of complex technology-mediated learning settings “through the lens of equity and opportunity” (Ito et al., 2013).

With the accelerated technological advancement, innovation has become a critical factor, which affects the core competitiveness of a company. However, studies about the relationship between internal stock option mechanisms and innovation productivity remain limited. Therefore, this paper aims to examine the impact of stock options and their elements design on innovation output from an internal mechanism perspective.

Using a sample of 302 stock option incentive plans announced and implemented between 2006 and 2016, this study uses the propensity score matching and difference-in-difference model to find out whether the implementation of stock options improves the innovation outputs of enterprises.

Based on the statistical analysis, it is concluded that: stock options can stimulate corporate innovation; a stock option may drive innovation outputs through two ways, performance-based incentives and risk-taking incentives, with the latter one playing a more dominant role and the risk-taking incentives of stock options, could be optimised when the non-executives granting proportion is larger, the granting range is limited, the incentive period is longer, the exercisable proportion is increasing, the price-to-strike ratio is lower and relatively loose performance assessment criteria are applied.

The conclusion reached in the study may provide valuable information to listed firms in designing and implementing the stock option plans.

The librarian and researcher have to be able to uncover specific articles in their areas of interest. This Bibliography is designed to help. Volume IV, like Volume III, contains features to help the reader to retrieve relevant literature from MCB University Press' considerable output. Each entry within has been indexed according to author(s) and the Fifth Edition of the SCIMP/SCAMP Thesaurus. The latter thus provides a full subject index to facilitate rapid retrieval. Each article or book is assigned its own unique number and this is used in both the subject and author index. This Volume indexes 29 journals indicating the depth, coverage and expansion of MCB's portfolio.