Shaw C. Feng, Paul Witherell, Gaurav Ameta and Duck Bong Kim
Additive manufacturing (AM) processes are the integration of many different science and engineering-related disciplines, such as material metrology, design, process planning…
Abstract
Purpose
Additive manufacturing (AM) processes are the integration of many different science and engineering-related disciplines, such as material metrology, design, process planning, in-situ and off-line measurements and controls. Major integration challenges arise because of the increasing complexity of AM systems and a lack of support among vendors for interoperability. The result is that data cannot be readily shared among the components of that system. In an attempt to better homogenization this data, this paper aims to provide a reference model for data sharing of the activities to be under-taken in the AM process, laser-based powder bed fusion (PBF).
Design/methodology/approach
The activity model identifies requirements for developing a process data model. The authors’ approach begins by formally decomposing the PBF processes using an activity-modeling methodology. The resulting activity model is a means to structure process-related PBF data and align that data with specific PBF sub-processes.
Findings
This model in this paper provides the means to understand the organization of process activities and sub-activities and the flows among them in AM PBF processes.
Research limitations/implications
The model is for modeling AM activities and data associated with these activity. Data modeling is not included in this work.
Social implications
After modeling the selected PBF process and its sub-processes as activities, the authors discuss requirements for developing the development of more advanced process data models. Such models will provide a common terminology and new process knowledge that improve data management from various stages in AM.
Originality/value
Fundamental challenges in sharing/reusing data among heterogeneous systems include the lack of common data structures, vocabulary management systems and data interoperability methods. In this paper, the authors investigate these challenges specifically as they relate to process information for PBF – how it is captured, represented, stored and accessed. To do this, they focus on using methodical, information-modeling techniques in the context of design, process planning, fabrication, inspection and quality control.
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Haeseong Jee and Paul Witherell
As the technology matures, design rules for additive manufacturing (AM) can help ensure manufacturability, which can be viewed as compatibility between designs and the fabrication…
Abstract
Purpose
As the technology matures, design rules for additive manufacturing (AM) can help ensure manufacturability, which can be viewed as compatibility between designs and the fabrication processes that produce those designs. Though often informal, current rules frequently provide direct guidelines or constraints for designing AM-destined parts. The aim of this paper is to standardize how design rules are developed and conveyed in AM by presenting design rules as sets of modular components and associated formalisms.
Design/methodology/approach
The proposed methodology decomposes fundamental geometry, process and material relationships into reusable modules. Independent of context, modular representations can be more easily interpreted and efficiently implemented than current one. By providing task-specific context, components are specialized to represent process-specific parameters for different AM builds and processes. This method of specialization enables designers to reconfigure design rules, rather than create new rules from scratch, thus preserving fundamental AM principles while supporting customization and explicit representation.
Findings
Modularity and formalisms provide both structure for the generalizations and a means to tailor that structure for a specific process, machine or build. The adoption of principles and formalisms that allow us to modify, extend, reconfigure or customize generalized rules as needed – instinctively and deliberately.
Originality/value
This method of specialization enables designers to reconfigure design rules, rather than create new rules from scratch, thus preserving fundamental AM principles while supporting customization and explicit representation.
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Keywords
Gijeong Seo, Md. RU Ahsan, Yousub Lee, Jong-Ho Shin, Hyungjun Park and Duck Bong Kim
Due to the complexity of and variations in additive manufacturing (AM) processes, there is a level of uncertainty that creates critical issues in quality assurance (QA), which…
Abstract
Purpose
Due to the complexity of and variations in additive manufacturing (AM) processes, there is a level of uncertainty that creates critical issues in quality assurance (QA), which must be addressed by time-consuming and cost-intensive tasks. This deteriorates the process repeatability, reliability and part reproducibility. So far, many AM efforts have been performed in an isolated and scattered way over several decades. In this paper, a systematically integrated holistic view is proposed to achieve QA for AM.
Design/methodology/approach
A systematically integrated view is presented to ensure the predefined part properties before/during/after the AM process. It consists of four stages, namely, QA plan, prospective validation, concurrent validation and retrospective validation. As a foundation for QA planning, a functional workflow and the required information flows are proposed by using functional design models: Icam DEFinition for Function Modeling.
Findings
The functional design model of the QA plan provides the systematically integrated view that can be the basis for inspection of AM processes for the repeatability and qualification of AM parts for reproducibility.
Research limitations/implications
A powder bed fusion process was used to validate the feasibility of this QA plan. Feasibility was demonstrated under many assumptions; real validation is not included in this study.
Social implications
This study provides an innovative and transformative methodology that can lead to greater productivity and improved quality of AM parts across industries. Furthermore, the QA guidelines and functional design models provide the foundation for the development of a QA architecture and management system.
Originality/value
This systematically integrated view and the corresponding QA plan can pose fundamental questions to the AM community and initiate new research efforts in the in-situ digital inspection of AM processes and parts.
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Martins Ugonna Obi, Patrick Pradel, Matt Sinclair and Richard Bibb
The purpose of this paper is to understand how Design for Additive manufacturing Knowledge has been developing and its significance to both academia and industry.
Abstract
Purpose
The purpose of this paper is to understand how Design for Additive manufacturing Knowledge has been developing and its significance to both academia and industry.
Design/methodology/approach
In this paper, the authors use a bibliometric approach to analyse publications from January 2010 to December 2020 to explore the subject areas, publication outlets, most active authors, geographical distribution of scholarly outputs, collaboration and co-citations at both institutional and geographical levels and outcomes from keywords analysis.
Findings
The findings reveal that most knowledge has been developed in DfAM methods, rules and guidelines. This may suggest that designers are trying to learn new ways of harnessing the freedom offered by AM. Furthermore, more knowledge is needed to understand how to tackle the inherent limitations of AM processes. Moreover, DfAM knowledge has thus far been developed mostly by authors in a small number of institutional and geographical clusters, potentially limiting diverse perspectives and synergies from international collaboration which are essential for global knowledge development, for improvement of the quality of DfAM research and for its wider dissemination.
Originality/value
A concise structure of DfAM knowledge areas upon which the bibliometric analysis was conducted has been developed. Furthermore, areas where research is concentrated and those that require further knowledge development are revealed.
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This paper proceeds from the basis that leadership can only be understood in context and by viewing it from the inside. In particular, it argues that the contextual complexity of…
Abstract
This paper proceeds from the basis that leadership can only be understood in context and by viewing it from the inside. In particular, it argues that the contextual complexity of small school leadership warrants attention from researchers, policy makers and system administrators and describes the nature of this complexity as depicted in the literature. It then reports a study being conducted in two states of Australia which examines the ways novice principals of small schools located in rural and remote areas make sense of, and deal with, the contextual complexity of their work. Finally, the paper discusses the implications of the study for promoting understanding of small school leadership and for developing authentic means of professional learning.
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George Cheney, Matt Noyes, Emi Do, Marcelo Vieta, Joseba Azkarraga and Charlie Michel
This chapter examines the intricacies of researching the initial preparation of school principals. First, the case is made for the importance of researching this formative stage…
Abstract
This chapter examines the intricacies of researching the initial preparation of school principals. First, the case is made for the importance of researching this formative stage in a principal's career trajectory. Second, an alignment is described between theory, research, and practice for informing fruitful approaches to preparation for the principalship. Third, a framework is articulated comprising four focal points portraying the complexities of principals' work. It is suggested that this framework could be used as a heuristic tool for connecting with the realities of the principal's world and the professional knowledge, skills, and dispositions that are required to perform the role effectively.
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George Cheney, Matt Noyes, Emi Do, Marcelo Vieta, Joseba Azkarraga and Charlie Michel
Sawsan Saadi Halbouni, Nada Obeid and Abeer Garbou
This paper aims to investigate the role of corporate governance and information technology in fraud prevention and detection within the United Arab Emirates (UAE).
Abstract
Purpose
This paper aims to investigate the role of corporate governance and information technology in fraud prevention and detection within the United Arab Emirates (UAE).
Design/methodology/approach
This study uses a survey of financial accountants and internal and external auditors to assess their perceptions of the effectiveness of IT and corporate governance as measured in terms of the audit committee’s effectiveness, internal audit functions, external audit functions, culture of honesty and employee training programmes in preventing and detecting fraud in the UAE.
Findings
The results indicate that corporate governance has a moderate role in preventing and detecting fraud in the UAE and that IT has the same role as traditional fraud prevention and detection techniques. The results also show no significant difference between internal and external auditors in their use of technological and traditional techniques during the course of audits.
Research limitations/implications
The findings suggest that the senior management and boards of directors must better understand the importance of their oversight function. The finding that a culture of honesty has a low positive impact on fraud prevention and detection in the UAE indicates that chief executive officers and boards of directors must make more efforts to set the “tone at the top” to improve the corporate environment in terms of integrity and ethics, among other factors. Furthermore, as IT and traditional techniques provide the same function, senior management and boards of directors must be alerted to the importance of developing systematic approaches to fraud investigation that involve greater reliance on technological approaches.
Practical implications
The moderate role of corporate governance suggests that senior management and boards of directors must better understand the importance of their oversight function to meet their obligations and fiduciary responsibilities to stakeholders. Furthermore, greater adoption of IT to detect and prevent fraud contributes to developing a systematic approach to fraud investigation, capable of identifying unusual activity using effective software.
Originality/value
This study contributes to the literature on the role of corporate governance and IT in preventing and detecting fraud, particularly for Middle Eastern countries and other emerging nations. The study may provide insights to academics and practitioners in the UAE and their international counterparts.