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Article
Publication date: 1 August 2001

José F. Rodríguez, James P. Thomas and John E. Renaud

An experimental study of the mechanical behavior of fused‐deposition (FD) ABS plastic materials is described. Elastic moduli and strength values are determined for the ABS…

Abstract

An experimental study of the mechanical behavior of fused‐deposition (FD) ABS plastic materials is described. Elastic moduli and strength values are determined for the ABS monofilament feedstock and various unidirectional FD‐ABS materials. The results show a reduction of 11 to 37 per cent in modulus and 22 to 57 per cent in strength for FD‐ABS materials relative to the ABS monofilament. These reductions occur due to the presence of voids and a loss of molecular orientation during the FD extrusion process. The results can be used to benchmark computational models for stiffness and strength as a function of the processing parameters for use in computationally optimizing the mechanical performance of FD‐ABS materials in functional applications.

Details

Rapid Prototyping Journal, vol. 7 no. 3
Type: Research Article
ISSN: 1355-2546

Keywords

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Article
Publication date: 14 November 2008

Victor M. Pérez, John E. Renaud and Layne T. Watson

To reduce the computational complexity per step from O(n2) to O(n) for optimization based on quadratic surrogates, where n is the number of design variables.

Abstract

Purpose

To reduce the computational complexity per step from O(n2) to O(n) for optimization based on quadratic surrogates, where n is the number of design variables.

Design/methodology/approach

Applying nonlinear optimization strategies directly to complex multidisciplinary systems can be prohibitively expensive when the complexity of the simulation codes is large. Increasingly, response surface approximations (RSAs), and specifically quadratic approximations, are being integrated with nonlinear optimizers in order to reduce the CPU time required for the optimization of complex multidisciplinary systems. For evaluation by the optimizer, RSAs provide a computationally inexpensive lower fidelity representation of the system performance. The curse of dimensionality is a major drawback in the implementation of these approximations as the amount of required data grows quadratically with the number n of design variables in the problem. In this paper a novel technique to reduce the magnitude of the sampling from O(n2) to O(n) is presented.

Findings

The technique uses prior information to approximate the eigenvectors of the Hessian matrix of the RSA and only requires the eigenvalues to be computed by response surface techniques. The technique is implemented in a sequential approximate optimization algorithm and applied to engineering problems of variable size and characteristics. Results demonstrate that a reduction in the data required per step from O(n2) to O(n) points can be accomplished without significantly compromising the performance of the optimization algorithm.

Originality/value

A reduction in the time (number of system analyses) required per step from O(n2) to O(n) is significant, even more so as n increases. The novelty lies in how only O(n) system analyses can be used to approximate a Hessian matrix whose estimation normally requires O(n2) system analyses.

Details

Engineering Computations, vol. 25 no. 8
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 1 June 2015

John Renaud, Scott Britton, Dingding Wang and Mitsunori Ogihara

Library data are often hard to analyze because these data come from unconnected sources, and the data sets can be very large. Furthermore, the desire to protect user…

Abstract

Purpose

Library data are often hard to analyze because these data come from unconnected sources, and the data sets can be very large. Furthermore, the desire to protect user privacy has prevented the retention of data that could be used to correlate library data to non-library data. The research team used data mining to determine library use patterns and to determine whether library use correlated to students’ grade point average.

Design/methodology/approach

A research team collected and analyzed data from the libraries, registrar and human resources. All data sets were uploaded into a single, secure data warehouse, allowing them to be analyzed and correlated.

Findings

The analysis revealed patterns of library use by academic department, patterns of book use over 20 years and correlations between library use and grade point average.

Research limitations/implications

Analysis of more narrowly defined user populations and collections will help develop targeted outreach efforts and manage the print collections. The data used are from one university; therefore, similar research is needed at other institutions to determine whether these findings are generalizable.

Practical implications

The unexpected use of the central library by those affiliated with law resulted in cross-education of law and central library staff. Management of the print collections and user outreach efforts will reflect more nuanced selection of subject areas and departments.

Originality/value

A model is suggested for campus partnerships that enables data mining of sensitive library and campus information.

Details

The Electronic Library, vol. 33 no. 3
Type: Research Article
ISSN: 0264-0473

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Article
Publication date: 1 September 2000

Jose F. Rodriguez, James P. Thomas and John E. Renaud

Fused‐deposition (FD) is a robotically controlled “fiber” extrusion process that produces a new class of materials with a variety of controllable mesostructural features…

Abstract

Fused‐deposition (FD) is a robotically controlled “fiber” extrusion process that produces a new class of materials with a variety of controllable mesostructural features related to fiber layout and the presence of voids. Mesostructural features of importance to the stiffness and strength of unidirectionally extruded materials were characterized as a function of the processing variables. Samples were made using the Stratasys FDM1600 Modeler with the P400 acrylonitrile‐butadiene‐styrene plastic. Results showed that the void geometry/density and the extent of bonding between contiguous fibers depended strongly on the fiber gap and extrusion flow rate. Settings for minimum void and maximum fiber‐to‐fiber bonding were determined. Void and bond length densities in the plane transverse to the fiber extrusion direction varied from 4 to 16 per cent and 39 to 73 per cent respectively. The results quantify the important mesostructural features as a function of the FD process variables and are expected to find use with other FD materials.

Details

Rapid Prototyping Journal, vol. 6 no. 3
Type: Research Article
ISSN: 1355-2546

Keywords

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Article
Publication date: 1 October 2003

José F. Rodríguez, James P. Thomas and John E. Renaud

Analytical/Computational models for the fused deposition (FD) material stiffness and strength as a function of mesostructural parameters are developed. Effective elastic…

Abstract

Analytical/Computational models for the fused deposition (FD) material stiffness and strength as a function of mesostructural parameters are developed. Effective elastic moduli are obtained using the strength of materials approach and an elasticity approach based on the asymptotic theory of homogenization. Theoretical predictions for unidirectional FD‐acrylonitrile butadiene styrene materials are validated with experimentally determined values of moduli and strength. For moduli predictions, the results were found to be satisfactory with difference between experimental and theoretical values of less than 10 percent in most cases.

Details

Rapid Prototyping Journal, vol. 9 no. 4
Type: Research Article
ISSN: 1355-2546

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Article
Publication date: 5 September 2016

Musa Mohammed Mukhtar, Roslan Amirudin and Ismail Mohamad

The purpose of this paper is to examine problems of housing delivery in Nigeria and propose some guiding principles that will lead to successful housing delivery in Nigeria.

Abstract

Purpose

The purpose of this paper is to examine problems of housing delivery in Nigeria and propose some guiding principles that will lead to successful housing delivery in Nigeria.

Design/methodology/approach

The study was conducted through in-depth analysis of some documents related to housing sector in Nigeria. These include National Housing Policy of Nigeria, Report of the Vision 2020 National Technical Working Group on Housing, as well as publications from UN-Habitat. Moreover, literature on the subject matter have been also reviewed.

Findings

Major constraints to housing delivery in Nigeria includes lack of effective housing finance system, unstable macroeconomic environment, difficulty in accessing land with secure tenure, high cost of building materials, shortages of skilled labour and poor infrastructural facilities.

Research limitations/implications

The major limitation of this study is that no interview or field survey to collect data from stakeholders has been performed.

Practical implications

The study can assist housing policy makers to understands important elements that must be incorporated in the national housing policies. It can also assist construction industries to understand how to improve efficiency and productivity in their projects.

Originality/value

The findings of this paper was based on previous studies of housing delivery and analysis of data from some formal and informal documents The findings from this study have been used to suggest some guiding principles that can assist in solving the housing delivery problems in Nigeria.

Details

Journal of Facilities Management, vol. 14 no. 4
Type: Research Article
ISSN: 1472-5967

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Article
Publication date: 8 June 2021

S. Sian and Stewart Smyth

The aim of this paper is to examine the changed nature of public accountability during a supreme emergency and explore how legal and auditing mechanisms have come to the…

Abstract

Purpose

The aim of this paper is to examine the changed nature of public accountability during a supreme emergency and explore how legal and auditing mechanisms have come to the fore, concluding that misappropriation of public monies is not an inevitable outcome.

Design/methodology/approach

The paper explores an illustrative example, the UK government's procurement of personal protective equipment during the early stages of the Covid-19 pandemic.

Findings

In circumstances of a supreme emergency where parliamentary scrutiny and competitive contract tendering are suspended, other forms of public accountability come to the fore, with civil society actors becoming more evident.

Research limitations/implications

The paper relies on illustrative examples based on the Westminster model of government. The study advanced the notion of deferred accountability and identifies areas for further study, potentially in different jurisdictions.

Social implications

The paper highlights the need for a variety of active and engaged civil society actors.

Originality/value

The paper contributes an empirical case to how an account of government behaviour is established. The paper also contributes to a deeper understanding of the nature and role of legal and government audit accountability mechanisms.

Details

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

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Abstract

Details

A History of the Assessment of Sex Offenders: 1830–2020
Type: Book
ISBN: 978-1-78769-360-9

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Article
Publication date: 13 March 2020

R.I. Ferguson, Karen Renaud, Sara Wilford and Alastair Irons

Cyber-enabled crimes are on the increase, and law enforcement has had to expand many of their detecting activities into the digital domain. As such, the field of digital…

Abstract

Purpose

Cyber-enabled crimes are on the increase, and law enforcement has had to expand many of their detecting activities into the digital domain. As such, the field of digital forensics has become far more sophisticated over the years and is now able to uncover even more evidence that can be used to support prosecution of cyber criminals in a court of law. Governments, too, have embraced the ability to track suspicious individuals in the online world. Forensics investigators are driven to gather data exhaustively, being under pressure to provide law enforcement with sufficient evidence to secure a conviction.

Yet, there are concerns about the ethics and justice of untrammeled investigations on a number of levels. On an organizational level, unconstrained investigations could interfere with, and damage, the organization's right to control the disclosure of their intellectual capital. On an individual level, those being investigated could easily have their legal privacy rights violated by forensics investigations. On a societal level, there might be a sense of injustice at the perceived inequality of current practice in this domain.

This paper argues the need for a practical, ethically grounded approach to digital forensic investigations, one that acknowledges and respects the privacy rights of individuals and the intellectual capital disclosure rights of organizations, as well as acknowledging the needs of law enforcement. The paper derives a set of ethical guidelines, and then maps these onto a forensics investigation framework. The framework to expert review in two stages is subjected, refining the framework after each stage. The paper concludes by proposing the refined ethically grounded digital forensics investigation framework. The treatise is primarily UK based, but the concepts presented here have international relevance and applicability.

Design/methodology/approach

In this paper, the lens of justice theory is used to explore the tension that exists between the needs of digital forensic investigations into cybercrimes on the one hand, and, on the other, individuals' rights to privacy and organizations' rights to control intellectual capital disclosure.

Findings

The investigation revealed a potential inequality between the practices of digital forensics investigators and the rights of other stakeholders. That being so, the need for a more ethically informed approach to digital forensics investigations, as a remedy, is highlighted and a framework proposed to provide this.

Research limitations/implications

The proposed ethically informed framework for guiding digital forensics investigations suggests a way of re-establishing the equality of the stakeholders in this arena, and ensuring that the potential for a sense of injustice is reduced.

Originality/value

Justice theory is used to highlight the difficulties in squaring the circle between the rights and expectations of all stakeholders in the digital forensics arena. The outcome is the forensics investigation guideline, PRECEpt: Privacy-Respecting EthiCal framEwork, which provides the basis for a re-aligning of the balance between the requirements and expectations of digital forensic investigators on the one hand, and individual and organizational expectations and rights, on the other.

Details

Journal of Intellectual Capital, vol. 21 no. 2
Type: Research Article
ISSN: 1469-1930

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Article
Publication date: 24 September 2019

Karen Renaud, Basie Von Solms and Rossouw Von Solms

The purpose of this paper is to position the preservation and protection of intellectual capital as a cyber security concern. The paper outlines the security requirements…

Abstract

Purpose

The purpose of this paper is to position the preservation and protection of intellectual capital as a cyber security concern. The paper outlines the security requirements of intellectual capital to help boards of directors (BoDs) and executive management teams to understand their responsibilities and accountabilities in this respect.

Design/methodology/approach

The research methodology is desk research. In other words, we gathered facts and existing research publications that helped us to define key terms, to formulate arguments to convince BoDs of the need to secure their intellectual capital and to outline actions to be taken by BoDs to do so.

Findings

Intellectual capital, as a valuable business resource, is related to information, knowledge and cyber security. Hence, preservation thereof is also related to cyber security governance and merits attention from BoDs.

Research limitations/implications

This paper clarifies BoDs intellectual capital governance responsibilities, which encompass information, knowledge and cyber security governance.

Practical implications

The authors hope that BoDs will benefit from the clarifications, and especially from the positioning of intellectual capital in cyber space.

Social implications

If BoDs know how to embrace their intellectual capital governance responsibilities, this will help to ensure that such intellectual capital is preserved and secured.

Originality/value

This paper extends a previous paper published by Von Solms and Von Solms, which clarified the key terms of information and cyber security, and the governance thereof. The originality and value is the focus on the securing of intellectual capital, a topic that has not yet received a great deal of attention from security researchers.

Details

Journal of Intellectual Capital, vol. 20 no. 5
Type: Research Article
ISSN: 1469-1930

Keywords

1 – 10 of 151