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Article
Publication date: 1 December 2002

Yong‐Tai Im and Daniel F. Walczyk

Focuses on Profiled Edge Lamination (PEL) tooling and the development of a new alogrithm, the Adaptively Vectored profiles Projection (AVPP), Describes the geometrical…

Abstract

Focuses on Profiled Edge Lamination (PEL) tooling and the development of a new alogrithm, the Adaptively Vectored profiles Projection (AVPP), Describes the geometrical relationships and heuristics for determining the abrasive water jet (AWJ) cutting orientation, position, and cutting sequence. The algorithm has ben implemented in a software program that can be used to generate machining code form PEL fabrication using a 5‐axis CNC AWJ cutting machine. Based on an investigation of cutting trajectory behavior on a challenging benchmark tool shape, the algorithm generates cutting paths that are well behaved, avoid any excessive leading or lagging of the AWJ cutting nozzle, and conform exactly to the original STL geometry. finally, an aluminium PEL tool used for hydroforming a production aluminium aircraft part was successfully fabricated using the AVPP algorithm and then demonstrated.

Details

Rapid Prototyping Journal, vol. 8 no. 5
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 3 April 2007

Robert E. Williams, Daniel F. Walczyk and Hoang T. Dang

To determine the feasibility of sealing and finishing conformal cooling/heating channels in profiled edge laminae (PEL) rapid tooling (RT) using abrasive flow machining (AFM).

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Abstract

Purpose

To determine the feasibility of sealing and finishing conformal cooling/heating channels in profiled edge laminae (PEL) rapid tooling (RT) using abrasive flow machining (AFM).

Design/methodology/approach

Sample PEL tools constructed of both aluminum and steel were designed and assembled for finishing by AFM. A simple design of experiments approach was utilized. Output parameters of interest included the material removal, surface roughness improvement and, most importantly, the ability to withstand a pressurized oil leak test.

Findings

AFM significantly improved the finish in the channels for aluminum and steel PEL tooling. Leak testing found that AFM also improved the sealing of both stacks at static pressures up to 690 kPa. The steel tooling appeared to benefit more from the AFM process. It has been postulated that the primary cause of the sealing is the plastic deformation of workpiece material in the plowing mode.

Research limitations/implications

The conformal channels studied had a simple cross‐sectional geometry and straight runs. The PEL tools were only made of two materials. However, the research results show great promise for large RT, including thermoforming and composite forming molds where temperature control is a critical issue.

Practical implications

The ability to seal the interfaces between individual laminae expands the potential application of AFM tremendously. AFM also has the potential to finish a wide range of internal passages in a variety of RT.

Originality/value

AFM has been previously used for finishing stereolithography prototypes. This is the first known attempt to seal and finish channels in laminated RT using AFM.

Details

Rapid Prototyping Journal, vol. 13 no. 2
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 1 September 2005

Seungryeol Yoo and Daniel Walczyk

To provide an advanced cutting trajectory algorithm for the profiled edge laminae (PEL) rapid tooling (RT) process, which is ideally suited for large‐scale dies and molds. The…

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Abstract

Purpose

To provide an advanced cutting trajectory algorithm for the profiled edge laminae (PEL) rapid tooling (RT) process, which is ideally suited for large‐scale dies and molds. The process involves assembling an array of laminae whose top edges are simultaneously profiled and beveled using a line‐of‐sight cutting method based on a CAD model of the intended tool surface.

Design/methodology/approach

The cutting profiles for an individual tool lamina are based on intersection curves obtained directly from the CAD model, and generated with exact geometrical accuracy. Two adjacent slice profiles, which define a lamination's top edge and are represented as polylines, are stitched together using an adaptive surface reconstruction algorithm. A cutting trajectory algorithm then develops a series of suitable cutting vectors (i.e. position and cutting direction) that minimize abrasive waterjet (AWJ) cutting errors due to non‐uniform motion and variations in kerf geometry resulting from process parameter variations. The proposed cutting trajectory generation process is demonstrated virtually for an actual production tool.

Findings

The proposed algorithm yields well‐behaved AWJ cutting trajectories for individual lamina used in a PEL tool that are better than those obtained using any other algorithm found in the literature.

Research limitations/implications

The algorithm is intended for use with AWJ cutting of PEL tool surfaces. Suggested future research includes assessment of the algorithm for other lamina cutting methods including laser cutting and wire‐type electro‐discharge machining, extending the algorithm to handle conformal cooling/heating channels and internal cavities, and application of the algorithm to several industrial tool case studies.

Practical implications

The algorithm generates cutting trajectories directly from CAD geometry that are ideal for AWJ cutting of profiled edge lamina. It will simply make industrial implementation of the PEL RT process easier.

Originality/value

This paper provides a new cutting trajectory algorithm for the PEL RT process that is a significant improvement over comparable algorithms proposed in the literature.

Details

Rapid Prototyping Journal, vol. 11 no. 4
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 5 June 2020

Lai Jiang, Xiaobo Peng and Daniel Walczyk

This paper aims to summarize the up-to-date research performed on combinations of various biofibers and resin systems used in different three-dimensional (3D) printing…

Abstract

Purpose

This paper aims to summarize the up-to-date research performed on combinations of various biofibers and resin systems used in different three-dimensional (3D) printing technologies, including powder-based, material extrusion, solid-sheet and liquid-based systems. Detailed information about each process, including materials used and process design, are described, with the resultant products’ mechanical properties compared with those of 3D-printed parts produced from pure resin or different material combinations. In most processes introduced in this paper, biofibers are beneficial in improving the mechanical properties of 3D-printed parts and the biodegradability of the parts made using these green materials is also greatly improved. However, research on 3D printing of biofiber-reinforced composites is still far from complete, and there are still many further studies and research areas that could be explored in the future.

Design/methodology/approach

The paper starts with an overview of the current scenario of the composite manufacturing industry and then the problems of advanced composite materials are pointed out, followed by an introduction of biocomposites. The main body of the paper covers literature reviews of recently emerged 3D printing technologies that were applied to biofiber-reinforced composite materials. This part is classified into subsections based on the form of the starting materials used in the 3D printing process. A comprehensive conclusion is drawn at the end of the paper summarizing the findings by the authors.

Findings

Most of the biofiber-reinforced 3D-printed products exhibited improved mechanical properties than products printed using pure resin, indicating that biofibers are good replacements for synthetic ones. However, synthetic fibers are far from being completely replaced by biofibers due to several of their disadvantages including higher moisture absorbance, lower thermal stability and mechanical properties. Many studies are being performed to solve these problems, yet there are still some 3D printing technologies in which research concerning biofiber-reinforced composite parts is quite limited. This paper unveils potential research directions that would further develop 3D printing in a sustainable manner.

Originality/value

This paper is a summary of attempts to use biofibers as reinforcements together with different resin systems as the starting material for 3D printing processes, and most of the currently available 3D printing techniques are included herein. All of these attempts are solutions to some principal problems with current 3D printing processes such as the limit in the variety of materials and the poor mechanical performance of 3D printed parts. Various types of biofibers are involved in these studies. This paper unveils potential research directions that would further widen the use of biofibers in 3D printing in a sustainable manner.

Details

Rapid Prototyping Journal, vol. 26 no. 6
Type: Research Article
ISSN: 1355-2546

Keywords

Book part
Publication date: 4 November 2021

Nicole A. Cooke

In an April 2018 webinar, the Freedom to Read Foundation asked the question: Do information consumers have the right to be misinformed? Fake news is nuanced, prolific, sometimes…

Abstract

In an April 2018 webinar, the Freedom to Read Foundation asked the question: Do information consumers have the right to be misinformed? Fake news is nuanced, prolific, sometimes malicious, often automated, and has the added complications of emotion, privacy, and ethics. And unfortunately, fake news and its foundational components of misinformation and disinformation (mis/dis), aren’t quickly fixed by learning a few information literacy strategies or media literacy concepts. People are inclined to believe what they want to believe despite training, awareness of critical thinking, and acknowledgement of widely held “objective facts.” Are they less intelligent or information poor because they choose to exist in their own information worlds and privilege their own confirmation biases?

Individuals have the right to seek, avoid, and use information for themselves as they see fit, regardless of whether or not others deem their information deficient, insufficient, or even false. However, this is a very black and white perspective on a much more complex and nuanced moral issue. Even if it is to their detriment, people ultimately do have the right to be misinformed, choosing the information they will and won’t accept. But information professionals should still be compelled to instruct patrons on the importance of seeking, finding, and using quality information and sources.

Details

Libraries and the Global Retreat of Democracy: Confronting Polarization, Misinformation, and Suppression
Type: Book
ISBN: 978-1-83982-597-2

Keywords

Article
Publication date: 12 October 2023

Mark Somers

This study aims to develop a framework for applying performance management principles to implementing a pluralistic model of scholarly impact in business schools to increase the…

Abstract

Purpose

This study aims to develop a framework for applying performance management principles to implementing a pluralistic model of scholarly impact in business schools to increase the value and relevance scholarly research to multiple stakeholder groups.

Design/methodology/approach

Performance management principles were studied with case study data of scholarly impact that included bibliographic measures and altmetrics. An analytical model was built for a focal business school that provided benchmarks for managing scholarly impact by using data from three peer schools.

Findings

Bibliographic, scholarly output measures and altmetrics were consistent across the focal school and peer schools, thereby providing a solid foundation for establishing performance benchmarks for annual performance reviews, promotion and tenure decisions and organizational impact goals.

Practical implications

This paper provides guidance for designing, building and implementing performance management systems to foster scholarly impact.

Originality/value

This paper integrates pluralistic impact models and performance management systems to build faculty expertise and align it with multiple impact domains.

Details

Quality Assurance in Education, vol. 32 no. 1
Type: Research Article
ISSN: 0968-4883

Keywords

Article
Publication date: 13 April 2012

Daniel G. Dorner and James Revell

The purpose of this paper is to report on a research project aimed at gaining an understanding of subject librarians' perceptions and promotion of institutional repositories as an…

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Abstract

Purpose

The purpose of this paper is to report on a research project aimed at gaining an understanding of subject librarians' perceptions and promotion of institutional repositories as an information resource for their clients.

Design/methodology/approach

The researchers used the five attributes of innovations and the change agent concept, both drawn from Rogers' diffusion of innovations theory, as the basis of semi‐structured interviews with nine librarians, spread equally across the humanities, social sciences, and sciences at three universities.

Findings

The researchers found that subject librarians have varying levels of knowledge about institutional repositories as an information resource and hold both positive and negative perceptions. The librarians perceived institutional repositories to be still underdeveloped, with greatest value for humanities clients and least value for science clients, offering little value to undergraduates, but a good resource for accessing theses.

Research limitations/implications

Due to their current perceptions of the value of institutional repositories, subject librarians are not yet promoting them as an information resource. If institutional repositories are to be successful, library managers must not only ensure that content is being input into the repositories, but also that they are being promoted to library clients as valuable information resources, so that the content is being accessed and used.

Originality/value

While there has been much research in recent years about institutional repositories, the focus has been predominantly on issues related to motivating individuals to input content into them. This research shows that institutional repositories are not yet being perceived or promoted as a valuable information resource by academic subject librarians, who view them as having varying value to their clients.

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